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  • 1801.
    Ali, Akbar
    et al.
    Riphah Int University, Pakistan.
    Fakhar-E-Alam, Muhammad
    GC University, Pakistan.
    Abbas, Najeeb
    GC University, Pakistan.
    Wazir, Zafar
    Riphah Int University, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Tufail, Muhammad
    Riphah Int University, Pakistan.
    Atif, M.
    King Saud University, Saudi Arabia; National Institute Laser and Optron, Pakistan.
    Silver-chitosan nanobiocomposite as urea biosensor2014In: Optoelectronics and Advanced Materials Rapid Communications, ISSN 1842-6573, E-ISSN 2065-3824, Vol. 8, no 11-12, p. 1238-1242Article in journal (Refereed)
    Abstract [en]

    Silver nanoparticles (Ag NPs) were synthesized by aqueous chemical growth technique. The above mentioned synthesized materials were characterized by applying scanning electron microscope (SEM) and X-ray diffraction for confirmation of morphological analysis, compositional purity, and crystalline property and emission characteristics as well. In order to fabricate the urea biosensor (potentiometric), a solution of deionized water and chitosan was prepared having Ag NPs. The said solution was dropped on the glass fiber filter having diameter of 2 cm. A wire of copper having thickness of approximately 500 pm was used for the voltage signal to pull out from the said working nanoparticles (NPs). To improve the strength, sensitivity and the quality of the potentiometric urea biosensor, a specific functional surface of Ag NPs was attained by electrostatic restrained of an enzyme (urease) onto the chitosan-Ag (a nanobiocomposite). The potentiometric reaction was measured via electrochemical detection technique. The potentiometric urea biosensor illustrates significant sensibility at room temperature with approximate to 42 mV as per span. Furthermore, the said biosensor showed an appropriate stable response within 7 sec.

  • 1802.
    Ali, Akhtar
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Comparative study of parallel programming models for multicore computing2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Shared memory multi-core processor technology has seen a drastic developmentwith faster and increasing number of processors per chip. This newarchitecture challenges computer programmers to write code that scales overthese many cores to exploit full computational power of these machines.Shared-memory parallel programming paradigms such as OpenMP and IntelThreading Building Blocks (TBB) are two recognized models that offerhigher level of abstraction, shields programmers from low level detailsof thread management and scales computation over all available resources.At the same time, need for high performance power-ecient computing iscompelling developers to exploit GPGPU computing due to GPU's massivecomputational power and comparatively faster multi-core growth. Thistrend leads to systems with heterogeneous architectures containing multicoreCPUs and one or more programmable accelerators such as programmableGPUs. There exist dierent programming models to program these architecturesand code written for one architecture is often not portable to anotherarchitecture. OpenCL is a relatively new industry standard framework, de-ned by Khronos group, which addresses the portability issue. It oers aportable interface to exploit the computational power of a heterogeneous setof processors such as CPUs, GPUs, DSP processors and other accelerators.

    In this work, we evaluate the eectiveness of OpenCL for programmingmulti-core CPUs in a comparative case study with two CPU specic stableframeworks, OpenMP and Intel TBB, for ve benchmark applicationsnamely matrix multiply, LU decomposition, image convolution, Pi value approximationand image histogram generation. The evaluation includes aperformance comparison of the three frameworks and a study of the relativeeects of applying compiler optimizations on performance numbers.OpenCL performance on two vendor-dependent platforms Intel and AMD,is also evaluated. Then the same OpenCL code is ported to a modern GPUand its code correctness and performance portability is investigated. Finally,usability experience of coding using the three multi-core frameworksis presented.

  • 1803.
    Ali, Akhtar
    et al.
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    Dastgeer, Usman
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Kessler, Christoph
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    OpenCL for programming shared memory multicore CPUs2011In: Fourth Swedish Workshop on Multi-Core Computing MCC-2011: November 23-25, 2011, Linköping University, Linköping, Sweden / [ed] Christoph Kessler, Linköping: Linköping University , 2011, Vol. S. 65-70, p. 65-70Conference paper (Other academic)
    Abstract [en]

    In this work, we evaluate the effectiveness of OpenCL for programming multicore CPUs in a comparative case study with OpenMP and Intel TBB for five benchmark applications: matrix multiply, LU decomposition, 2D image convolution, Pi value approximation and image histogram generation.

  • 1804.
    Ali, Akhtar
    et al.
    Linköping University, The Institute of Technology.
    Dastgeer, Usman
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    Kessler, Christoph
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
    OpenCL for programming shared memory multicore CPUs2012In: Proceedings of the 5th Workshop on MULTIPROG2012 / [ed] E. Ayguade, B. Gaster, L. Howes, P. Stenström, O. Unsal, HiPEAC Network of Excellence , 2012Conference paper (Refereed)
    Abstract [en]

    Shared memory multicore processor technology is pervasive in mainstream computing. This new architecture challenges programmers to write code that scales over these many cores to exploit the full computational power of these machines. OpenMP and Intel Threading Building Blocks (TBB) are two of the popular frameworks used to program these architectures. Recently, OpenCL has been defined as a standard by Khronos group which focuses on programming a possibly heterogeneous set of processors with many cores such as CPU cores, GPUs, DSP processors. In this work, we evaluate the effectiveness of OpenCL for programming multicore CPUs in a comparative case study with OpenMP and Intel TBB for five benchmark applications: matrix multiply, LU decomposition,2D image convolution, Pi value approximation and image histogram generation. The evaluation includes the effect of compiler optimizations for different frameworks, OpenCL performance on different vendors’ platformsand the performance gap between CPU-specific and GPU-specific OpenCL algorithms for execution on a modern GPU. Furthermore, a brief usability evaluation of the three frameworks is also presented.

  • 1805.
    Ali Arslan, Mehmet
    et al.
    Lund University, Sweden.
    Gruian, Flavius
    Lund University, Sweden.
    Kuchcinski, Krzysztof
    Lund University, Sweden.
    Karlsson, Andreas
    Linköping University, Department of Electrical Engineering. Linköping University, Faculty of Science & Engineering.
    Code Generation for a SIMD Architecture with Custom Memory Organisation2016In: PROCEEDINGS OF THE 2016 CONFERENCE ON DESIGN AND ARCHITECTURES FOR SIGNAL and IMAGE PROCESSING, IEEE , 2016, p. 90-97Conference paper (Refereed)
    Abstract [en]

    Todays multimedia and DSP applications impose requirements on performance and power consumption that only custom processor architectures with SIMD capabilities can satisfy. However, the specific features of such architectures, including vector operations and high-bandwidth complex memory organization, make them notoriously complicated and time consuming to program. In this paper we present an automated code generation approach that dramatically reduces the effort of programming such architectures, by carrying out instruction scheduling and memory allocation based on a constraint programming formulation. Furthermore, the quality of the generated code is close to that of hand-written code by an experienced programmer with knowledge of the architecture. We demonstrate the viability of our approach on an existing custom heterogeneous DSP architecture, by compiling and running a number of typical DSP kernels, and comparing the results to hand-optimized code.

  • 1806.
    Ali, Asif
    et al.
    Linköping University, Department of Computer and Information Science.
    Ramzan, Faheem
    Linköping University, Department of Computer and Information Science.
    Analysis and Monitoring of Team Collaboration in Emergency Response Training supported by a Web Based Information Management System2009Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Our objective in this thesis work is to analyze and manage the log files which are generated after a number of experiments series on different groups using C3Fire simulation environment. It includes analyzing and extracting information from log files, and then maintaining this information in a database. This should be presented with a web interface through ICEfaces Ajax framework for Java. Log Files are generated after a number of experiments series on the different groups. All sequences and information related to task performed by team in group is organized in session log files. The work is divided into different steps; first step is to analyze and extract data from log files, and properly arrange it in several different tables in a database, for this MySQL database is used to store the information. The web interface of log file management system is implemented using ICEfaces Ajax framework, and is based on the statistics of log files generated from the C3Fire environment.  User would be able to add/remove the log files, also can view or edit the details of each session log file in database through web interface. Different events can be generated, and logged for the session information.

    C3Fire is an environment that supports training and research in team collaboration. The environment is mainly used in command, control and communication research, and in training of team decision making. Many humanitarian relief operations are doing their work without having any practice. When some disaster events occur, they cannot perform their jobs effectively. Effective and efficient relief operation is the need of humanity; even that’s not enough to move teams to the disaster place at right time; communication and co-ordination among the team members is the big factor to make effective and well-organized work. C3Fire is a simulation system which provides the training for team members to handle such type of disaster events, and makes the work more proficient at that time by doing effective coordination.

  • 1807.
    Ali, Baland
    et al.
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Peuravaara, Mattias
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Grävmaskinsstyrning med en eller två GNSS-mottagare2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today's increasing demand for greater efficiency in the construction industry has led to the need for corporate machines to be modernized to keep up with competitors. The modernization can be of different natures, amongst other the introduction of dual satellite based receivers on excavators that NCC Construction want investigated.

    The imposition of machine control systems with dual satellite based receivers, GNSS-receivers, is alleged to contribute to efficiency and a higher degree of accuracy. This report is a comparison of the relatively new system that uses two receivers with at this stage frequently used system with only one receiver.

    The comparison has been conducted by field measurements, calculations based on theoretical models and interviews with, in the field, qualified staff. The report also deals with economic aspects, in which the calculations are simplified, in order to get an overall picture of the costs and potential savings´for a possible future investment. Upgrading to machine control systems with dual GNSS-receivers did not show any major improvement when positioning the bucket. Despite the fact that a theoretical analysis shows that the positioning should be improved considerably.

    The reason for the lack of improvement could be that too few machines were examined. The survey shows that such an advanced technology as GNSS machine control requires careful maintenance in order to achieve expected accuracy. Economically, it appears that systems with two receivers are a good alternative in the event of an investment. However, which of the excavators to be equipped with the system, should be carefully evaluated depending on the excavator main tasks.

  • 1808.
    Ali, Gulzar
    et al.
    University of Sindh, Pakistan.
    Tahira, Aneela
    Luleå University of Technology, Sweden.
    Begum Mallah, Arfana
    University of Sindh, Pakistan.
    Ahmed Mallah, Sarfraz
    University of Sindh, Pakistan.
    Ibupoto, Akila
    Shah Abdul Latif University, Pakistan.
    Ahmed Khand, Aftab
    Tsinghua University, Peoples R China.
    Baradi, Waryani
    University of Sindh, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Yu, Cong
    Chinese Academic Science, Peoples R China.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan; Chinese Academic Science, Peoples R China.
    Functional CuO Microstructures for Glucose Sensing2018In: Journal of Electronic Materials, ISSN 0361-5235, E-ISSN 1543-186X, Vol. 47, no 2, p. 1519-1525Article in journal (Refereed)
    Abstract [en]

    CuO microstructures are produced in the presence of water-soluble amino acids by hydrothermal method. The used amino acids include isoleucine, alpha alanine, and arginine as a soft template and are used for tuning the morphology of CuO nanostructures. The crystalline and morphological investigations were carried out by x-ray diffraction (XRD) and scanning electron microscopy techniques. The XRD study has shown that CuO material obtained in the presence of different amino acids is of high purity and all have the same crystal phase. The CuO microstructures prepared in the presence of arginine were used for the development of sensitive and selective glucose biosensor. The linear range for the glucose detection are from 0.001 mM to 30 mM and limit of detection was found to be 0.0005 mM. The sensitivity was estimated around 77 mV/decade. The developed biosensor is highly selective, sensitive, stable and reproducible. The glucose biosensor was used for the determination of real human blood samples and the obtained results are satisfactory. The CuO material is functional therefore can be capitalized in wide range of applications such as lithium ion batteries, all oxide solar cells and supercapacitors.

  • 1809.
    Ali, Islam
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Iqbal, Wasim
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Performance analysis of various antennas at 2.45 GHz2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this era of technology, there is a swift increase in the number of applications which operate at the Industrial Scientific Medical Band. The applications of this band ranges from home microwave oven to wireless local area networks (WLAN). Therefore, the design of antennas on this band is essential.

    This thesis work revolves around the detailed study and design of various antennas at 2.45 GHz. All the simulation of the antennas was performed using advanced design system (ADS). Microstrip antenna technology is commonly used in antenna design due to its advantages such as low-profile, small size and easy fabrication on printed circuit boards.

    Firstly, various antennas such as rectangular patch, square patch, dipole, inverted F and printed Yagi were designed using ADS and their different performance parameters such as input impedance matching, voltage standing wave ratio (VSWR), input reflection, and gain and directivity were discussed. Dipole antenna, inverted F and printed Yagi were fabricated on printed circuit board (PCB) to compare their measured and simulated results.

    At the end, a conclusion is drawn for different antennas based on their various performance parameters.

  • 1810.
    Ali Kamyabi, Mohammad
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Hajari, Nasim
    University of Zanjan, Iran .
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Tiwari, Ashutosh
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    A high-performance glucose biosensor using covalently immobilised glucose oxidase on a poly(2,6-diaminopyridine)/carbon nanotube electrode2013In: Talanta: The International Journal of Pure and Applied Analytical Chemistry, ISSN 0039-9140, E-ISSN 1873-3573, Vol. 116, p. 801-808Article in journal (Refereed)
    Abstract [en]

    A highly-sensitive glucose biosensor amenable to ultra-miniaturisation was fabricated by immobilisation of glucose oxidase (GOx), onto a poly(2,6-diaminopyridine)/multi-walled carbon nanotube/glassy carbon electrode (poly(2,6-DP)/MWNT/GCE). Cyclic voltammetry was used for both the electrochemical synthesis of poly-(2,6-DP) on the surface of a MWNT-modified GC electrode, and characterisation of the polymers deposited on the GC electrode. The synergistic effect of the high active surface area of both the conducting polymer, i.e., poly-(2,6-DP) and MWNT gave rise to a remarkable improvement in the electrocatalytic properties of the biosensor. The transfer coefficient (alpha), heterogeneous electron transfer rate constant and Michaelis-Menten constant were calculated to be 0.6, 4 s(-1) and 0.20 mM at pH 7.4, respectively. The GOx/poly(2,6-DP)/MWNT/GC bioelectrode exhibited two linear responses to glucose in the concentration ranging from 0.42 mu M to 8.0 mM with a correlation coefficient of 0.95, sensitivity of 52.0 mu AmM-1 cm(-2), repeatability of 1.6% and long-term stability, which could make it a promising bioelectrode for precise detection of glucose in the biological samples. (C) 2013 Elsevier B.V. All rights reserved.

  • 1811.
    Ali Kamyabi, Mohammad
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering. Zanjan University, Iran.
    Hajari, Nasim
    Zanjan University, Iran.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Tiwari, Ashutosh
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Correction: A high-performance glucose biosensor using covalently immobilised glucose oxidase on a poly(2,6-diaminopyridine)/carbon nanotube electrode (vol 116, pg 801, 2013)2016In: Talanta: The International Journal of Pure and Applied Analytical Chemistry, ISSN 0039-9140, E-ISSN 1873-3573, Vol. 153, p. 414-415Article in journal (Refereed)
    Abstract [en]

    A highly-sensitive glucose biosensor amenable to ultraminiaturisation was fabricated by immobilization of glucose oxidase (wGOX), onto a poly(2,6-diaminopyridine)/multi-walled carbon nanotube/glassy carbon electrode (poly(2,6-DP)/MWCNT/GCE). Cyclic voltammetry was used for both the electrochemical synthesis of poly-(2,6-DP) on the surface of a MWCNT-modified GC electrode, and characterization of the polymers deposited on the GC electrode. The synergistic effect of the high active surface area of both the conducting-polymer, i.e., poly-(2,6-DP) and MWCNT gave rise to a remarkable improvement in the electrocatalytic properties of the biosensor. The transfer coefficient (alpha), heterogeneous electron transfer rate constant and Michaelis-Menten constant were calculated to be 0.6, 4 s-1 and 0.22 mM at pH 7.4, respectively. The GOx/poly(2,6-DP)/MWCNT/GC bioelectrode exhibited two linear responses to glucose in the concentration ranging from 0.42 mu M to 8.0 mM with a correlation coefficient of 0.95, sensitivity of 52.0 mu AmM-1 cm-2, repeatability of 1.6% and long-term stability, which could make it a promising bioelectrode for precise detection of glucose in the biological samples. (C) 2016 Elsevier B.V. All rights reserved.

  • 1812.
    Ali Khan, Ghazanfar
    et al.
    Department of Chemistry, Umeå University, Umeå, Sweden.
    Berglund, Björn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Maqbool Khan, Kashif
    College of Pharmacy, University of Punjab, Lahore, Pakistan.
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Fick, Jerker
    Department of Chemistry, Umeå University, Umeå, Sweden.
    Occurrence and Abundance of Antibiotics and Resistance Genes in Rivers, Canal and near Drug Formulation Facilities – A Study in Pakistan2013In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, no 6Article in journal (Refereed)
    Abstract [en]

    Antibiotic resistance (AR) is a global phenomenon that has severe epidemiological ramifications world-wide. It has been suggested that antibiotics that have been discharged into the natural aquatic environments after usage or manufacture can promote the occurrence of antibiotic resistance genes (ARG). These environmental ARGs could serve as a reservoir and be horizontally transferred to human-associated bacteria and thus contribute to AR proliferation. The aim of this study was to investigate the anthropogenic load of antibiotics in Northern Pakistan and study the occurrence of ARGs in selected samples from this region. 19 sampling sites were selected; including six rivers, one dam, one canal, one sewage drain and four drug formulation facilities. Our results show that five of the rivers have antibiotic levels comparable to surface water measurements in unpolluted sites in Europe and the US. However, high levels of antibiotics could be detected in the downstream river in close vicinity of the 10 million city Lahore, 1100, 1700 and 2700 ng L−1 for oxytetracycline, trimethoprim, and sulfamethoxazole respectively. Highest detected levels were at one of the drug formulation facilities, with the measured levels of 1100, 4100, 6200, 7300, 8000, 27000, 28000 and 49000 ng L−1 of erythromycin, lincomycin, ciprofloxacin, ofloxacin, levofloxacin, oxytetracycline, trimethoprim and sulfamethoxazole respectively. ARGs were also detected at the sites and the highest levels of ARGs detected, sulI and dfrA1, were directly associated with the antibiotics detected at the highest concentrations, sulfamethoxazole and trimethoprim. Highest levels of both antibiotics and ARGs were seen at a drug formulation facility, within an industrial estate with a low number of local residents and no hospitals in the vicinity, which indicates that the levels of ARGs at this site were associated with the environmental levels of antibiotics.

  • 1813.
    Ali, L
    et al.
    Gothenburg University, Sweden Swedish Institute Health Science, Sweden Sahlgrens University Hospital, Sweden .
    Ahlstrom, B H
    Gothenburg University, Sweden Swedish Institute Health Science, Sweden University of West, Sweden .
    Krevers, Barbro
    Linköping University, Department of Medical and Health Sciences, Physiotherapy. Linköping University, Faculty of Health Sciences.
    Skarsater, I
    Gothenburg University, Sweden Swedish Institute Health Science, Sweden Sahlgrens University Hospital, Sweden .
    Daily life for young adults who care for a person with mental illness: a qualitative study2012In: Journal of Psychiatric and Mental Health Nursing, ISSN 1351-0126, E-ISSN 1365-2850, Vol. 19, no 7, p. 610-617Article in journal (Refereed)
    Abstract [en]

    Accessible summary The burden of caring for a person with mental illness has been transferred to families and close friends. Daily life for young informal carers is unpredictable and they need to stay alert and prepared for events beyond their control. Young informal carers are concerned young adults who support a family member or friend unconditionally. Supporting a friend is related to as a great a sense of individual responsibility as supporting a family member. Abstract This study describes the daily life and management strategies of young informal carers of family members or friends with mental illness. Twelve young adults (three men and nine women; 1625 years old) in Sweden were voluntarily recruited between February and May 2008. Data collected through eight individual semi-structured interviews and one focus group interview were analysed using qualitative content analysis. The findings revealed nine subthemes that were further grouped into three main themes: showing concern, providing support and using management strategies. Participants lived in constant readiness for something unexpected to happen to the person they cared for, and their role in the relationship could change quickly from family member or friend to guardian or supervisor. Supporting a friend was considered as large a personal responsibility as supporting a family member. Their management strategies were based on individual capacities and their ability to step aside should the situation become too demanding. These young informal carers need support in caring for the mentally ill. As the internet becomes increasingly fundamental to daily life, support could be provided most effectively through person-centred web sites.

  • 1814.
    Ali, Lilas
    et al.
    Institute of Health and Care Sciences, Sahlgrenska Academy, Gothenburg University.
    Hedman Ahlström, Britt
    Department of Nursing, Health and Culture, University West, Trollhättan.
    Krevers, Barbro
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Health Sciences.
    Sjöström, Nils
    Institute of Health and Care Sciences, Sahlgrenska Academy, Gothenburg University.
    Skärsäter, Ingela
    School of Social and Health Sciences, Halmstad University.
    Support for young informal carers of persons with mental illness: a mixed-method study.2013In: Issues in mental health nursing, ISSN 1096-4673, Vol. 34, no 8, p. 611-8Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to explore how young (16-25 year old) informal carers of a person with a mental illness experience and use support. In a mixed method approach, we interviewed 12 young carers, and 241 completed a self-administered questionnaire. While the young carers strive to maintain control, their main support seems to be others in their lives, who often define the situation differently. The carers said web-support, counseling, and group counseling might be helpful, yet very few had any professional support. Young carers are greatly in need of support and it should be provided.

  • 1815.
    Ali, Lilas
    et al.
    Gothenburg University, Sweden Swedish Institute Health Science, Sweden Sahlgrens University Hospital, Sweden .
    Krevers, Barbro
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Health Sciences. Vårdal Institute, The Swedish Institute for Health Science, Sweden.
    Sjostrom, Nils
    Gothenburg University, Sweden Sahlgrens University Hospital, Sweden .
    Skarsater, Ingela
    Gothenburg University, Sweden Swedish Institute Health Science, Sweden Sahlgrens University Hospital, Sweden Halmstad University, Sweden .
    Effectiveness of web-based versus folder support interventions for young informal carers of persons with mental illness: A randomized controlled trial2014In: Patient Education and Counseling, ISSN 0738-3991, E-ISSN 1873-5134, Vol. 94, no 3, p. 362-371Article in journal (Refereed)
    Abstract [en]

    Objective: Compare the impact of two interventions, a web-based support and a folder support, for young persons who care for people who suffer from mental illness. Methods: This study was a randomized control trial, following the CONSORT statements, which compared the impact of two interventions. Primary outcome variable was stress, and secondary outcome variables were caring situation, general self-efficacy, well-being, health, and quality of life of young informal carers (N = 241). Data were collected in June 2010 to April 2011, with self-assessment questionnaires, comparing the two interventions and also to detect changes. Results: The stress levels were high in both groups at baseline, but decreased in the folder group. The folder group had improvement in their caring situation (also different from the web group), general self-efficacy, well-being, and quality of life. The web group showed increase in well-being. Conclusion: Young informal carers who take on the responsibility for people close to them; suffer consequences on their own health. They live in a life-situation characterized by high stress and low wellbeing. This signals a need for support. Practice implications: The non-significant differences show that each intervention can be effective, and that it depends upon the individuals preferences. This highlights the importance of adopting person-centered approach, in which young persons can themselves choose support strategy.

  • 1816.
    Ali, Lilas
    et al.
    University of Gothenburg, Sweden; Swedish Institute Health Science, Sweden; Swedish Institute Health Science, Sweden.
    Krevers, Barbro
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Medicine and Health Sciences. Swedish Institute Health Science, Sweden; Swedish Institute Health Science, Sweden.
    Skarsater, Ingela
    University of Gothenburg, Sweden; Swedish Institute Health Science, Sweden; Swedish Institute Health Science, Sweden; Sahlgrens University Hospital, Sweden; Halmstad University, Sweden.
    Caring Situation, Health, Self-efficacy, and Stress in Young Informal Carers of Family and Friends with Mental Illness in Sweden2015In: Issues in Mental Health Nursing, ISSN 0161-2840, E-ISSN 1096-4673, Vol. 36, no 6, p. 407-415Article in journal (Refereed)
    Abstract [en]

    This study compared the caring situation, health, self-efficacy, and stress of young (16-25) informal carers (YICs) supporting a family member with mental illness with that of YICs supporting a friend. A sample of 225 carers, assigned to a family group (n = 97) or a friend group (n = 128) completed the questionnaire. It was found that the family group experiences a lower level of support and friends experienced a lower positive value of caring. No other differences in health, general self-efficacy and stress were found. YICs endure different social situations, which is why further study of the needs of YICs, especially those supporting friends, is urgently needed.

  • 1817.
    Ali, M.
    et al.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Svensk, Olle
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Zhen, Z.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Suihkonen, S.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Törmä, P.T.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Lipsanen, H.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Sopanen, M.
    Helsinki University of Technology (TKK), Micronova, Department of Micro and Nanosciences, P.O. Box 3500, FIN-02015 TKK, Finland.
    Hjort, Klas
    Department of Engineering Sciences, Uppsala University, P.O. Box 534, SE-75121 Uppsala, Sweden.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Reduced photoluminescence from InGaN/GaN multiple quantum well structures following 40 MeV iodine ion irradiation2009In: Physica. B, Condensed matter, ISSN 0921-4526, E-ISSN 1873-2135, ISSN 0921-4526, Vol. 404, no 23-24, p. 4925-4928Article in journal (Refereed)
    Abstract [en]

    The effects following ion irradiation of GaN-based devices are still limited. Here we present data on the photoluminescence (PL) emitted from InGaN/GaN multiple quantum well (MQW) structures, which have been exposed to 40 MeV I ion irradiation. The PL is reduced as a function of applied ion fluence, with essentially no PL signal left above 1011 ions/cm2. It is observed that even the ion fluences in the 109 ions/cm2 range have a pronounced effect on the photoluminescence properties of the MQW structures. This may have consequences concerning application of InGaN/GaN MQW’s in radiation-rich environments, in addition to defect build-up during ion beam analysis.

  • 1818.
    Ali Malik, Muhammad
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Science & Engineering.
    Gatto, Emanuela
    University Roma Tor Vergata.
    Macken, Stephen
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Science & Engineering.
    DiNatale, Corrado
    University Roma Tor Vergata.
    Paolesse, Roberto
    University Roma Tor Vergata.
    DAmico, Arnaldo
    University Roma Tor Vergata.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Filippini, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Imaging fingerprinting of excitation emission matrices2009In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 635, no 2, p. 196-201Article in journal (Refereed)
    Abstract [en]

    The spectral fingerprinting of the excitation emission matrix (EEM) of fluorescent substances is demonstrated using polychromatic light sources and tri-chromatic image detectors. A model of the measured fingerprints explaining their features and classification performance, based on the polychromatic excitation of the indicators is proposed.

    Substantial amount of spectral information is retained in the fingerprints as corroborated by multivariate analysis and experimental conditions that favor such situation are identified.

    In average, for five different substances, the model shows a fitting goodness measured by the Pearsons r coefficient and the root mean square deviation of 0.8541 and 0.0247 respectively, while principal component classification patterns satisfactorily compare with the EEM spectroscopy classification and respectively explain 96% and 93% of the information in the fist two principal components.

    The measurements can be performed using regular computer screens as illumination and web cameras as detectors, which constitute ubiquitous and affordable platforms compatible with distributed evaluations, in contrast to regular instrumentation for EEM measurements.

  • 1819.
    Ali, Neserin
    et al.
    Lund Univ, Sweden.
    Ljunggren, Stefan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Occupational and Environmental Medicine Center.
    Karlsson, Helen
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Occupational and Environmental Medicine Center.
    Wierzbicka, Aneta
    Lund Univ, Sweden.
    Pagels, Joakim
    Lund Univ, Sweden.
    Isaxon, Christina
    Lund Univ, Sweden.
    Gudmundsson, Anders
    Lund Univ, Sweden.
    Rissler, Jenny
    Lund Univ, Sweden.
    Nielsen, Jorn
    Lund Univ, Sweden.
    Lindh, Christian H.
    Lund Univ, Sweden.
    Karedal, Monica
    Lund Univ, Sweden.
    Comprehensive proteome analysis of nasal lavage samples after controlled exposure to welding nanoparticles shows an induced acute phase and a nuclear receptor, LXR/RXR, activation that influence the status of the extracellular matrix2018In: Clinical Proteomics, ISSN 1542-6416, E-ISSN 1559-0275, Vol. 15, article id 20Article in journal (Refereed)
    Abstract [en]

    Background: Epidemiological studies have shown that many welders experience respiratory symptoms. During the welding process a large number of airborne nanosized particles are generated, which might be inhaled and deposited in the respiratory tract. Knowledge of the underlying mechanisms behind observed symptoms is still partly lacking, although inflammation is suggested to play a central role. The aim of this study was to investigate the effects of welding fume particle exposure on the proteome expression level in welders suffering from respiratory symptoms, and changes in protein mediators in nasal lavage samples were analyzed. Such mediators will be helpful to clarify the pathomechanisms behind welding fume particle-induced effects. Methods: In an exposure chamber, 11 welders with work-related symptoms in the lower airways during the last month were exposed to mild-steel welding fume particles (1 mg/m(3)) and to filtered air, respectively, in a double-blind manner. Nasal lavage samples were collected before, immediately after, and the day after exposure. The proteins in the nasal lavage were analyzed with two different mass spectrometry approaches, label-free discovery shotgun LC-MS/MS and a targeted selected reaction monitoring LC-MS/MS analyzing 130 proteins and four in vivo peptide degradation products. Results: The analysis revealed 30 significantly changed proteins that were associated with two main pathways; activation of acute phase response signaling and activation of LXR/RXR, which is a nuclear receptor family involved in lipid signaling. Connective tissue proteins and proteins controlling the degradation of such tissues, including two different matrix metalloprotease proteins, MMP8 and MMP9, were among the significantly changed enzymes and were identified as important key players in the pathways. Conclusion: Exposure to mild-steel welding fume particles causes measurable changes on the proteome level in nasal lavage matrix in exposed welders, although no clinical symptoms were manifested. The results suggested that the exposure causes an immediate effect on the proteome level involving acute phase proteins and mediators regulating lipid signaling Proteases involved in maintaining the balance between the formation and degradation of extracellular matrix proteins are important key proteins in the induced effects.

  • 1820.
    Ali, Neserin
    et al.
    Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
    Mattsson, Karin
    Center for Molecular Protein Science, Biochemistry and Structural Biology, Lund University, Lund, Sweden.
    Rissler, Jenny
    Department of Design Sciences, Ergonomic and Aerosol Technology, Lund University, Lund, Sweden.
    Karlsson, Helen Marg
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Occupational and Environmental Medicine Center.
    Svensson, Christian R
    Department of Design Sciences, Ergonomic and Aerosol Technology, Lund University, Lund, Sweden.
    Gudmundsson, Anders
    Department of Design Sciences, Ergonomic and Aerosol Technology, Lund University, Lund, Sweden.
    Lindh, Christian H
    Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
    Jönsson, Bo A G
    Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
    Cedervall, Tommy
    Center for Molecular Protein Science, Biochemistry and Structural Biology, Lund University, Lund, Sweden.
    Kåredal, Monica
    Division of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
    Analysis of nanoparticle-protein coronas formed in vitro between nanosized welding particles and nasal lavage proteins.2016In: Nanotoxicology, ISSN 1743-5390, E-ISSN 1743-5404, Vol. 10, no 2, p. 226-234Article in journal (Refereed)
    Abstract [en]

    Welding fumes include agglomerated particles built up of primary nanoparticles. Particles inhaled through the nose will to some extent be deposited in the protein-rich nasal mucosa, and a protein corona will be formed around the particles. The aim was to identify the protein corona formed between nasal lavage proteins and four types of particles with different parameters. Two of the particles were formed and collected during welding and two were manufactured iron oxides. When nasal lavage proteins were added to the particles, differences were observed in the sizes of the aggregates that were formed. Measurements showed that the amount of protein bound to particles correlated with the relative size increase of the aggregates, suggesting that the surface area was associated with the binding capacity. However, differences in aggregate sizes were detected when nasal proteins were added to UFWF and Fe2O3 particles (having similar agglomerated size) suggesting that yet parameters other than size determine the binding. Relative quantitative mass spectrometric and gel-based analyses showed differences in the protein content of the coronas. High-affinity proteins were further assessed for network interactions. Additional experiments showed that the inhibitory function of secretory leukocyte peptidase inhibitor, a highly abundant nasal protein, was influenced by particle binding suggesting that an understanding of protein function following particle binding is necessary to properly evaluate pathophysiological events. Our results underscore the importance of including particles collected from real working environments when studying the toxic effects of particles because these effects might be mediated by the protein corona.

  • 1821.
    Ali, Rahman
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Design of Building Blocks in Digital Baseband Transceivers for Body-Coupled Communication2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Advances in communication technologies continue to increase information sharing among the people.~Short-range wireless networking technologies such as Bluetooth or ZigBee, which are mainly used for data transfer over short range, will, however, suffer from network congestion, high power consumption and security issues in the future.

    The body-coupled communication (BCC), a futuristic short-range wireless technology, uses the human body as a transmission medium. In BBC channel, a small electric field is induced onto the human body which enables the propagation of a signal between communication devices that are in the proximity or direct contact with the human body. The direct baseband transmission and simple architecture make BCC an attractive candidate for a future short-range wireless communication technology in particular applications such as body area network.

    The main focus of this thesis is on the design and implementation of digital baseband transmitter and receiver for the body-coupled communication. The physical layer (PHY) implementation of the digital baseband transmitter and receiver is inspired from the IEEE 802.3 Ethernet transmission protocol. The digital design is implemented at RTL level using hardware description language (VHDL). The functionality of the digital baseband transmitter and receiver is demonstrated by developing data transfer application layers.

  • 1822.
    Ali Rashed, Chra
    et al.
    Linköping University, Department of Management and Engineering, Business Administration.
    Mouyiasis, George
    Linköping University, Department of Management and Engineering, Business Administration.
    Negative Unintended Consequences of Innovation- a case study regarding innovation and sustainability: The new Extended Value Creation Mechanism for Global Sustainability, the SNE SFI GS-framework2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Innovation is often related to positive outcomes for the majority to enjoy that enhances welfare and facilitates everyday activities. In different fields of study (economics, management, sociology, history and science and technology) it is becoming a field of magnitude (Malerba and Brusoni, 2007). Fagerberg and Verspagen (2009) discuss the emerging interest of innovation in the field of social science. Although the interest within the subject of innovation is high, very little research has been done regarding the aim to contribute to the design innovation policy, developed by scholars studying the field of innovation. One often so neglected study within innovation is in the field of negative unintended consequences of innovation (NUCoI) (Sveiby et al, 2012). One main contributor of innovative activities is organizational operations leading to value for end customers. While firms often have the aim to create value with innovation for the greater benefit in society, sometimes these value-creating mechanisms may create unintended negative consequences in addition to the positive effects. While innovations are increasing in rapidness and numbers of output produced, the effects on society and the natural environment needs to be highlighted. With assumptions regarding vague CSR implementation in corporations (Newell, 2005), this research tries to grasp understanding on how NUCoI is perceived from the managerial perspective in organizations regarding their stakeholder viewpoint. As a starting point, the authors use Charlie Chaplin’s famous quote “More than machinery, we need humanity” from the movie “The Great Dictator” indicating the importance of caring for various stakes.

    Purpose: The aim of this research is to highlight the new field of study in social science; Negative unintended consequences of innovation (NUCoI) in relation to the societal natural environment (society and the natural environment). The research contributes to the existing frameworks on organizational value creation mechanisms in innovation policy to incorporate the aspect of negative consequences of innovation (NCoI), in terms of sustainability to highlight the importance of secondary stakeholders.

    Results: The new Extended Value Creation Mechanism for Global Sustainability, the Societal-Natural-Environment Stakeholder Framework of Innovation and Global Sustainability framework (SNE SFI GS-framework), aims to contribute in the long-term perspective for research in innovation policy by highlighting one aspect of a field of the often so neglected societal natural environment perspective, when competing rivalry becomes too fierce. The framework highlights the importance of secondary stakeholders, where primary stakeholders may act as a “link” between the organization and secondary stakeholders. Additionally, the authors suggest going to basic practices regarding sustainability with valuating the natural resources for a prospering sustainable society. The aspects in the research include stakeholder-theory, value-creation in terms of the societal natural environment, and innovation as a field of social science, negative consequences and organizational sense-making.

  • 1823.
    Ali Shah, Syed Asmat
    et al.
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Qazi, Sohaib Ayaz
    Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology.
    Design of an all-digital, reconfigurable sigma-deltamodulator2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis presents a model of reconfigurable sigma-delta modulator. These modulators areintended for high speed digital Digital to Analog Converters. The modulators are intendedto reduce complexity of current steering DACs and also considered as a front end of dataconverters. Quantization noise present in digital signal is pushed to higher frequencies bysigma-delta modulators. Noise in high band frequencies can be removed by a low pass filter.

    A test methodology involving generation of baseband signal, interpolation and digitizationis opted. Topologies tested in MATLAB® include signal feedback and error feedback modelsof first-order and second-order sigma-delta modulators. Error feedback and signal feedbackfirst-order modulators’ performance is quite similar. The SNR of a first-order error feedbackmodel is 52.3 dB and 55.9 dB for 1 and 2 quantization bits, respectively. In second-orderSDM, signal feedback provides best performance with 80 dB SNR.

    The other part of the thesis focuses on the implementation of the sigma-delta modulator(SDM) using faster time to market approach. SoC Encounter, a tool from Cadence, is theeasiest way to do this job. The modulators are implemented in 65-nm technology. The reconfigurablesigma-delta modulator is designed using Verilog-HDL language. Switches areintroduced to control the reconfigurable SDM for different input word lengths. Word-lengthcan vary from 0 to 4 bits. Modulator is designed to work for frequencies of 2 GHz. To netlistthe design, Design Compiler is used which is a tool from Synopsys®.

    The area of the chip reported by design compiler is 563.68 um. When the design is implementedin SoC Encounter, area of the chip is increased, because the core utilization, whiledesigning, is only 60%, which is 556.8 um. Remaining 40% area is used by buffers, inverterand filler cells during clock tree synthesis. The buffers and inverters are added to removethe clock phase delay between different registers. Power consumption of the chip is 319mW.Internal power of the modulators is 219.1 mW. Switching power of output capacitances is99.9 mW, which is 31% of the total power consumed. Main concern of the power loss isconsidered to be power leakage. To reduce the leakage power and achieve high speed designCORE65GPHVT libraries are used. Leakage power of the design is 2.825 uW which is0.00088% of the total power.

  • 1824.
    Ali, Sharafat
    et al.
    Linnaeus University, Sweden; Corning Inc, NY 14831 USA.
    Paul, Biplab
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Magnusson, Roger
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Jonson, Bo
    Linnaeus University, Sweden.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Birch, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Synthesis and characterization of the mechanical and optical properties of Ca-Si-O-N thin films deposited by RF magnetron sputtering2017In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 315, p. 88-94Article in journal (Refereed)
    Abstract [en]

    Ca-Si-O-N thin films were deposited on commercial soda-lime silicate float glass, silica wafers and sapphire substrates by RF magnetron co-sputtering from Ca and Si targets in an Ar/N-2/O-2 gas mixture. Chemical composition, surface morphology, hardness, reduced elastic modulus and optical properties of the films were investigated using X-ray photoelectron spectroscopy, scanning electron microscopy, nanoindentation, and spectroscopic ellipsometry. It was found that the composition of the films can be controlled by the Ca target power, predominantly, and by the reactive gas flow. Thin films in the Ca-Si-O-N system are composed of N and Ca contents up to 31 eq. % and 60 eq. %, respectively. The films thickness ranges from 600 to 3000 nm and increases with increasing Ca target power. The films surface roughness varied between 2 and 12 nm, and approximately decreases with increasing power of Ca target. The hardness (4-12 GPa) and reduced elastic modulus (65-145 GPa) of the films increase and decrease with the N and Ca contents respectively. The refractive index (1.56-1.82) is primarily dictated by the N content. The properties are compared with findings for bulk glasses in the Ca-Si-(Al)-O-N systems, and it is concluded that Ca-Si-O-N thin films have higher values of hardness, elastic modulus and refractive index than bulk glasses of similar composition. (C) 2017 Elsevier B.V. All rights reserved.

  • 1825.
    Ali, Sharafat
    et al.
    Linnaeus Univ, Sweden.
    Paul, Biplab
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Magnusson, Roger
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Ekström, Erik
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Pallier, Camille
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. RISE IVF, S-58188 Linkoping, Sweden.
    Jonson, Bo
    Linnaeus Univ, Sweden.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Birch, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Optical and mechanical properties of amorphous Mg-Si-O-N thin films deposited by reactive magnetron sputtering2019In: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 372, p. 9-15Article in journal (Refereed)
    Abstract [en]

    In this work, amorphous thin films in Mg-Si-O-N system typically containing amp;gt; 15 at.% Mg and 35 at.% N were prepared in order to investigate especially the dependence of optical and mechanical properties on Mg composition. Reactive RF magnetron co-sputtering from magnesium and silicon targets were used for the deposition of Mg-Si-O-N thin films. Films were deposited on float glass, silica wafers and sapphire substrates in an Ar, N-2 and O-2 gas mixture. X-ray photoelectron spectroscopy, atomic force microscopy, scanning electron microscopy, spectroscopic ellipsometry, and nanoindentation were employed to characterize the composition, surface morphology, and properties of the films. The films consist of N and Mg contents up to 40 at.% and 28 at.%, respectively and have good adhesion to substrates and are chemically inert. The thickness and roughness of the films increased with increasing content of Mg. Both hardness (16-21 GPa) and reduced elastic modulus (120-176 GPa) are strongly correlated with the amount of Mg content. The refractive index up to 2.01 and extinction coefficient up to 0.18 were found to increase with Mg content. The optical band gap (3.1-4.3) decreases with increasing the Mg content. Thin film deposited at substrate temperature of 100 degrees C shows a lower value of hardness (10 GPa), refractive index (1.75), and higher values of reduced elastic modulus (124 GPa) as compared to the thin film deposited at 310 degrees C and 510 degrees C respectively, under identical synthesis parameters.

  • 1826.
    Ali, Sharafat
    et al.
    Linnaeus University, Sweden.
    Paul, Biplab
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Magnusson, Roger
    Linköping University, Department of Physics, Chemistry and Biology, Applied Optics . Linköping University, Faculty of Science & Engineering.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Broitman, Esteban
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Jonson, Bo
    Linnaeus University, Sweden.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Birch, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Novel transparent Mg-Si-O-N thin films with high hardness and refractive index2016In: Vacuum, ISSN 0042-207X, E-ISSN 1879-2715, Vol. 131Article in journal (Refereed)
    Abstract [en]

    There is an increasing demand for glass materials with better mechanical and optical properties for display and electronic applications. This paper describes the deposition of novel thin films of Mg-circle divide-Si-O-N onto float glass substrates. Amorphous thin films in the Mg-Si-O-N system with high nitrogen and magnesium contents were deposited by reactive RF magnetron co-sputtering from Mg and Si targets in Ar/N-2/O-2 gas mixtures. The thin films studied span an unprecedented range of compositions up to 45 at% Mg and 80 at% N out of cations and anions respectively. Thin films in the Mg-Si-O-N system were found to be homogeneous and transparent in the visible region. Mechanical properties like hardness (H) and reduced elastic modulus (Er) show high values, up to 21 GPa and 166 GPa respectively. The refractive index (1.87-2.00) increases with increasing magnesium and nitrogen contents. (C) 2016 Elsevier Ltd. All rights reserved.

  • 1827.
    Ali, Sofia
    Linköping University, Department of Social and Welfare Studies. Linköping University, Faculty of Arts and Sciences.
    "Varför ska de inte välja svensken framför mig?": Invandrarungdomars föreställningar om möjligheter och svårigheter på den svenska arbetsmarknaden.2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Denna studie bygger på sju invandrarungdomars föreställningar om möjligheter och svårigheter på den svenska arbetsmarknaden. I fokus för studien står särskilt ungdomarnas berättelser om de vägval de gjort, som de står inför och som de skulle vilja göra, när det gäller att etablera sig på arbetsmarknaden. Med hjälp av en semistrukturerad intervjuguide utfördes intervjuer med ungdomarna varpå dessa analyserades och tolkades i enlighet med meningskoncentreringsprincipen. Det teoretiska ramverk som använts för att tolka och analysera ungdomarnas berättelser har legat i led med Pierre Bourdieus habitusbegrepp och praktiskt sinne, kapitalbegreppen samt sekundära karaktäristika. Resultatet visar att det finns ett driv hos ungdomarna att arbeta men att de känner sig motarbetade och förbisedda på arbetsmarknaden. De upplever att deras invandrarskap innebär att de behöver prestera dubbelt så bra i arbete och studier för att en arbetsgivare ska få upp ögonen för dem, för ”varför ska de inte välja svensken framför mig?”. Även bristande kontaktnät innebär ett underläge för invandrarungdomarna jämfört med deras svenska arbetssökande vänner. De förlitar sig inte på att någon förälder eller familjemedlem kommer att kunna hjälpa de få in foten på arbetsmarknaden eftersom de möjligheterna är begränsade. Sammantaget är de överens om att de i rollen som invandrare eller barn till invandrare sitter i en position som innebär att de inte har samma möjligheter som en etniskt svensk har i arbetssammanhang. 

  • 1828.
    Ali, Sofia
    et al.
    Linköping University, Department of Social and Welfare Studies.
    Mohamed, Suad
    Linköping University, Department of Social and Welfare Studies.
    Kurd i hemmet men svensk i samhället: En studie av unga kurdiska kvinnors förhållningssätt till sig själva och det svenska samhället2009Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I denna studie analyseras fem unga kurdiska kvinnors upplevelser av sina levnadsförhållanden i Sverige. Utifrån en kvalitativ undersökningsmetod och med hjälp av intervjuer, har faktorer som språk, föräldrarnas religion, traditioner och kultur granskats. Studiens teoretiska ram utgörs till stor del av diaspora, etnicitet och kultur, men även identitet, genus och stigma har använts som centrala teorier. Utöver dessa har flerspråkighet som begreppsdefinition haft en betydande roll för analysen och informanternas upplevelser och tankar.

    Vi har i studien dragit slutsatsen att de kurdiska kvinnorna mer eller mindre har assimilerats in i det svenska samhället genom att de delvis har glömt bort sitt modersmål eller refererar till sig själva som svenskar. Detta av den anledning att de inte vill hamna i utanförskap och menar att det finns en klyfta mellan den svenska och kurdiska kulturen. Denna klyfta kulturerna emellan ökade efter att två hedersrelaterade våldshandlingar utfördes mot kurdiska flickor, och informanterna menar att det är en av anledningarna till varför många idag har fördomar gentemot kurder.

  • 1829.
    Ali Soomro, Razium
    et al.
    University of Sindh, Pakistan.
    Hallam, Keith Richard
    University of Bristol, UK.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan.
    Tahira, Aneela
    University of Sindh, Pakistan.
    Tufail Hussain Sherazi, Syed
    University of Sindh, Pakistan.
    Juddin, Siraj
    University of Sindh, Pakistan.
    Jawaid, Sana
    University of Sindh, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Glutaric Acid Assisted Fabrication of CuO Nanostructures and their Application in Development of Highly Sensitive Electrochemical Sensor System for Carbamates2016In: Electroanalysis, ISSN 1040-0397, E-ISSN 1521-4109, Vol. 28, no 7, p. 1634-1640Article in journal (Refereed)
    Abstract [en]

    This work describes the fabrication of unique arrow head shaped CuO nanostructures using simple hydrothermal treatment method. The highly attractive features were obtained by the application of glutaric acid utilised simultaneous as template and functionalising agent. The functionalised nanostructures were known to possess excellent potential towards the electro-catalytic oxidation of carbofuran pesticide. The generated intense electrochemical signal with lower potential value enabled sensitive and selective determination of carbofuran up to 1 x 10(-3) mu M with wide sensing window in range of 0.01 to 0.16 mu M. The feasibility of the developed sensor system for the practical application was also studied by testing its potential in real sample extracts of various vegetables. The excellent recoveries demonstrated the analytical robustness of the developed sensor system. The sensor system utilises a new and simple approach towards sensitive determination of toxic pesticides reflecting its wide spectrum application in various fields.

  • 1830.
    Ali Soomro, Razium
    et al.
    University of Sindh, Pakistan.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan.
    Sirajuddin,
    University of Sindh, Pakistan.
    Ishaq Abro, Muhammad
    Mehran University of Engineering & Technology, Pakistan .
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Controlled synthesis and electrochemical application of skein-shaped NiO nanostructures2015In: Journal of Solid State Electrochemistry, ISSN 1432-8488, E-ISSN 1433-0768, Vol. 19, no 3, p. 913-922Article in journal (Refereed)
    Abstract [en]

    A simple, economical and mild solution chemistry method was used to synthesize diverse nickel oxide (NiO) nanostructures employing methionine as a growth-directing agent. The as-synthesized NiO nanostructures were observed to possess a unique skein-shape morphology with uniform spherical distribution. The NiO nanoskein (NiO NSk) formation was extensively studied using X-ray diffraction (XRD), X-ray photoelectron microscopy (XPS), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) techniques, respectively. The unique NiO NSks exhibited better electrocatalytic activity towards glucose oxidation in alkaline media, enabling the development of a highly sensitive non-enzymatic glucose sensor. The observed analytical properties included high sensitivity (1915 mu A mM(-1) cm(-2)), wide linear range (0.1-5.0 mM), low detection limit (0.7 mu M), higher stability and reproducibility. Moreover, the sensor is selective in the presence of interfering species such as ascorbic acid (AA), uric acid (UA) and dopamine (DP) during the non-enzymatic glucose sensing. The worthy-of-notice electrocatalytic activity and economical feasible preparation of NiO NSk-shaped electroactive material for direct glucose-sensing applications make the present study of high interest for the fabrication of low-cost devices. A NiO NSk-based glucose sensor has also been employed for glucose determination in human serum with adequate results, suggesting high potential for the routine monitoring of glucose from biotechnology, clinical and food industry samples.

  • 1831.
    Ali Soomro, Razium
    et al.
    University of Bristol, England; University of Sindh, Pakistan.
    Hussain Ibupoto, Zafar
    Dr MA Kazi Institute Chemistry University of Sindh, Pakistan.
    Tufail Hussain Sirajuddin; Sherazi, Syed
    University of Sindh, Pakistan.
    Ishaq Abro, Muhammad
    Mehran University of Engn and Technology, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Practice of diclofenac sodium for the hydrothermal growth of NiO nanostructures and their application for enzyme free glucose biosensor2016In: Microsystem Technologies: Micro- and Nanosystems Information Storage and Processing Systems, ISSN 0946-7076, E-ISSN 1432-1858, Vol. 22, no 10, p. 2549-2557Article in journal (Refereed)
    Abstract [en]

    In this study diclofenac sodium (DFS), an analgesic drug has been employed as an effective template for the synthesis of NiO nanostructures. The NiO nanostructures were synthesised using low temperature hydrothermal growth method, both in the presence and absence of the DFS drug. The synthesised nanostructures were studied for their structural, compositional and electrochemical properties using scanning electron microscopy, X-ray diffraction and cyclic voltammetry. The synthesised nanostructures were then utilised for the modification of glassy carbon electrode which were then utilised for the electro-catalytic enzyme free glucose sensing in alkaline media. The competitive experiments suggested that although, both nanostructures possess excellent capability of glucose sensing, the NiO nanoflakes modified electrode was found to be twice as much as sensitive (2584 A mu A mM(-1) cm(-2)) as nanoflowers based electrode (1154 A mu A mM(-1) cm(-2)). The NiO nanoflakes based sensor further demonstrated excellent anti-interference potential in the presence of common interferents like uric acid, ascorbic acid and dopamine. In addition, the successful application NiO nanoflakes based sensor to determine real blood glucose concentration further suggest its feasibility for real sample analysis.

  • 1832.
    Ali Soomro, Razium
    et al.
    University of Bristol, England; University of Sindh, Pakistan.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan.
    Tufail Hussain Sirajuddin; Sherazi, Syed
    Univ Sindh, Natl Ctr Excellence Analyt Chem, Jamshoro 76080, Pakistan.
    Ishaq Abro, Muhammad
    Mehran University of Engn and Technology, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Ahmed Mahesar, Sarfaraz
    University of Sindh, Pakistan.
    Hussain Kalwar, Nazar
    University of Sindh, Pakistan.
    Glycine-assisted preparation of Co3O4 nanoflakes with enhanced performance for non-enzymatic glucose sensing2015In: MATERIALS EXPRESS, ISSN 2158-5849, Vol. 5, no 5, p. 437-444Article in journal (Refereed)
    Abstract [en]

    In this study a simple, inexpensive and efficient route is proposed to synthesise attractive cobalt oxide (Co3O4) nanostructures using glycine as an effective growth controller and regulator. The as-synthesised Co3O4 nanostructures were observed to possess unique nanoflake shape morphological features with highly dense distribution. The formation of Co3O4 nanoflakes (Co3O4 NFKs) was elaborately explored using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Scanning electron microscopy (SEM) respectively. The unique Co3O4 nanoflakes were known to possess excellent electro-catalytic potential for the oxidation of glucose in alkaline medium. This potential property allowed successful development of highly sensitive (1180 mu A mM(-1) cm(-2)), selective and stable non-enzymatic glucose sensor. In addition, the developed sensor had a wide working range (0.1-5.0 mM), low limit of detection (0.7 mu M), and excellent reproducibility, besides the capability of analysing real blood glucose samples.

  • 1833.
    Ali Soomro, Razium
    et al.
    University of Bristol, England; University of Sindh, Pakistan.
    Nafady, Ayman
    King Saud University, Saudi Arabia; Sohag University, Egypt.
    Hallam, Keith Richard
    University of Bristol, England.
    Jawaid, Sana
    University of Sindh, Pakistan.
    Al Enizi, Abdullah
    King Saud University, Saudi Arabia.
    Tufail Hussain Sherazi, Syed
    University of Sindh, Pakistan.
    Sirajuddin,
    Univ Sindh, Natl Ctr Excellence Analyt Chem, Jamshoro 76080, Pakistan.
    Ibupoto, Zafar Hussain
    Univ Sindh, Dr MA Kazi Inst Chem, Jamshoro 76080, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Highly sensitive determination of atropine using cobalt oxide nanostructures: Influence of functional groups on the signal sensitivity2016In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 948, p. 30-39Article in journal (Refereed)
    Abstract [en]

    This study describes sensitive determination of atropine using glassy carbon electrodes (GCE) modified with Co3O4 nanostructures. The as-synthesised nanostructures were grown using cysteine (CYS), glutathione (GSH) and histidine (HYS) as effective templates under hydrothermal action. The obtained morphologies revealed interesting structural features, including both cavity-based and flower-shaped structures. The as-synthesised morphologies were noted to actively participate in electro-catalysis of atropine (AT) drug where GSH-assisted structures exhibited the best signal response in terms of current density and over-potential value. The study also discusses the influence of functional groups on the signal sensitivity of atropine electro-oxidation. The functionalisation was carried with the amino acids originally used as effective templates for the growth of Co3O4 nanostructures. The highest increment was obtained when GSH was used as the surface functionalising agent. The GSH-functionalised Co3O4-modified electrode was utilised for the electro-chemical sensing of AT in a concentration range of 0.01 -0.46 mu M. The developed sensor exhibited excellent working linearity (R-2 = 0.999) and signal sensitivity up to 0.001 mu M of AT. The noted high sensitivity of the sensor is associated with the synergy of superb surface architectures and favourable interaction facilitating the electron transfer kinetics for the electro-catalytic oxidation of AT. Significantly, the developed sensor demonstrated excellent working capability when used for AT detection in human urine samples with strong anti-interference potential against common co-existing species, such as glucose, fructose, cysteine, uric acid, dopamine and ascorbic acid. (C) 2016 Elsevier B.V. All rights reserved.

  • 1834.
    Ali Soomro, Razium
    et al.
    University of Sindh, Pakistan; University of Bristol, England.
    Nafady, Aynam
    King Saud University, Saudi Arabia; Sohag University, Egypt.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan.
    Tufail Hussain Sirajuddin; Sherazi, Syed
    University of Sindh, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Ishaq Abro, Muhammad
    Mehran University of Engn and Technology, Pakistan.
    Development of sensitive non-enzymatic glucose sensor using complex nanostructures of cobalt oxide2015In: Materials Science in Semiconductor Processing, ISSN 1369-8001, E-ISSN 1873-4081, Vol. 34, p. 373-381Article in journal (Refereed)
    Abstract [en]

    The study reports the synthesis of cobalt oxide (Co3O4) nanostructures and their application in enzyme free electrochemical sensing of glucose. The synthesized nanostructures were elaborately characterized via number of analytical techniques including scanning electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The as-synthesized nanostructures of Co3O4 were found to exhibited nanodisc like morphology with the size dimension in range of 300-500 nm. The obtained morphological features were evaluated for their electrochemical potential towards oxidation of glucose which enabled development of sensitive (27.33 mu A mM(-1) cm(-2)), and stable enzyme free glucose sensor. In addition, the developed sensor showed excellent linearity (r(2)=0.9995), wide detection range (0.5-5.0 mM), lower detection limit (0.8 mu M) and extreme selectivity towards glucose in the presence of common interferents like dopamine (DP), ascorbic acid (AA) and uric acid (UA). The successfully application of developed sensor for real blood glucose analysis further reflects its capability for routine glucose measurement.

  • 1835.
    Ali Soomro, Razium
    et al.
    University of Bristol, England; University of Sindh, Pakistan.
    Richard Hallam, Keith
    University of Bristol, England.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan.
    Tahira, Aneela
    University of Sindh, Pakistan.
    Jawaid, Sana
    University of Sindh, Pakistan.
    Tufail Hussain Sherazi, Syed
    University of Sindh, Pakistan.
    Sirajjuddin,
    Univ Sindh, Natl Ctr Excellence Analyt Chem, Jamshoro 76080, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    A highly selective and sensitive electrochemical determination of melamine based on succinic acid functionalized copper oxide nanostructures2015In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 5, no 127, p. 105090-105097Article in journal (Refereed)
    Abstract [en]

    This study presents the development of a highly selective and sensitive electrochemical sensor for the determination of melamine from aqueous environments. The sensor system is based on functionalised marigold-like CuO nanostructures fabricated using a controlled hydrothermal process, where the utilised succinic acid is considered to play a dual role as a functionalising and growth controlling agent (modifier). The fabricated nanostructures exhibit sharp and well-ordered structural features with dimensions (thickness) in the range of 10-50 nm. The sensor system exhibits strong linearity within the concentration range of 0.1 x 10(-9) to 5.6 x 10(-9) M and demonstrates an excellent limit of detection up to 0.1 x 10(-10) M. The extreme selectivity and sensing capability of the developed sensor is attributed to the synergy of selective interaction between succinic acid and melamine moieties, and the high surface area of marigold-like CuO nanostructures. In addition to this, the developed sensor was also utilised for the determination of melamine from real milk samples collected from different regions of Hyderabad, Pakistan. The obtained excellent recoveries proved the feasibility of the sensor for real life applications. The sensor system offers an operative measure for detecting extremely low melamine content with high selectivity in food contents.

  • 1836.
    Ali Soomro, Razium
    et al.
    University of Bristol, England; University of Sindh, Pakistan.
    Richard Hallam, Keith
    University of Bristol, England.
    Hussain Ibupoto, Zafar
    University of Sindh, Pakistan.
    Tahira, Aneela
    University of Sindh, Pakistan.
    Tufail Hussain Sherazi, Syed
    University of Sindh, Pakistan.
    Sanam Sirajjuddin; Memon, Safia
    University of Sindh, Pakistan.
    Willander, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Amino acid assisted growth of CuO nanostructures and their potential application in electrochemical sensing of organophosphate pesticide2016In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 190, p. 972-979Article in journal (Refereed)
    Abstract [en]

    This work reports a highly sensitive electrochemical sensor for organophosphate pesticide (malathion) based on unique and attractive CuO nanostructures. The discussed nanostructures were synthesized using low temperature hydrothermal growth method utilizing green amino acids such as glycine, serine, threonine and histidine as effective bio-compatible templates. The morphological evaluation demonstrated formation of unique and attractive 1-D nanostructures reflecting the effective growth controlling and directing capabilities of the utilized amino acids. The as-synthesized CuO nanostructures were noted to possess high affinity towards malathion which enabled their application as electrode material for the development of affinity based electrochemical sensor. Although, the as-synthesized morphologies were all sensitive towards malathion but the glycine directed triangular flake-like nanostructures exhibited greater sensitivity compared to other competitors. The electrochemical behaviour of the modified electrodes was studied using cyclic voltammetry (CV) whereas, differential pulse voltammetry (DPV) was utilized for the analytical evaluation of the sensor. The developed sensor demonstrated high reproducibility, stability, wide detection window (1-12 nM), and sensitivity to detect malathion up to 0.1 nM based on suppressive signal measurement. In addition, the sensor system exhibited high anti-interference capability in the presence of common co-existing pesticides like lindane, carbendazim, and trichlorfon. The developed sensor provides an effective measure for detecting extremely low concentration of malathion with wide applicability in various fields. (C) 2015 Elsevier Ltd. All rights reserved.

  • 1837.
    Ali, Syed M. Usman
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
    Fabrication and characterization of ZnO nanostructures for sensing and photonic device applications2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Nanotechnology is an emerging inter-disciplinary paradigm which encompasses diverse fields of science and engineering converge at the nanoscale. This nanoscale science and nanostructure engineering have well demonstrated in the fabrication of sensors/transducers devices with faster response time and better sensitivity then the planer version of the sensor’s configurations. Nanotechnology is not just to grow/fabricate nanostructures by just mixing nanoscale materials together but it requires the ability to understand and to precisely manipulate and control of the developed nanomaterials in a useful way. Nanotechnology is aiding to substantially improve, even revolutionize, many technology and industry sectors like information technology, energy, environmental science, medicine/medical instrumentation, homeland security, food safety, and transportation, among many others. Such applications of nanotechnology are delivering in both expected and unexpected ways on nanotechnology’s promise to benefit the society.

    The semiconductor ZnO with wide band gap (~ 3.37 eV) is a distinguish and unique material and its nanostructures have attracted great attention among the researchers due to its peculiar properties such as large exciton binding energy (60 meV) at room temperature, the high electron mobility, high thermal conductivity, good transparency and easiness of fabricating it in the different type of nanostructures. Based on all these fascinating properties, ZnO have been chosen as a suitable material for the fabrication of photonic, transducers/sensors, piezoelectric, transparent and spin electronics devices etc. The objective of the current study is to highlight the recent developments in materials and techniques for electrochemical sensing and hetrostructure light emitting diodes (LEDs) luminescence properties based on the different ZnO nanostructures. The sensor devices fabricated and characterized in the work were applied to determine and monitor the real changes of the chemical or biochemical species. We have successfully demonstrated the application of our fabricated devices as primary transducers/sensors for the determination of extracellular glucose and the glucose inside the human fat cells and frog cells using the potentiometric technique. Moreover, the fabricated ZnO based nanosensors have also been applied for the selective determination of uric acid, urea and metal ions successfully. This thesis relates specifically to zinc oxide nanostructure based electrochemical sensors and photonic device (LED) applications.

    List of papers
    1. A fast and sensitive potentiometric glucose microsensor based on glucose oxidase coated ZnO nanowires grown on a thin silver wire
    Open this publication in new window or tab >>A fast and sensitive potentiometric glucose microsensor based on glucose oxidase coated ZnO nanowires grown on a thin silver wire
    2010 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 145, no 2, p. 869-874Article in journal (Refereed) Published
    Abstract [en]

    In this study, a potentiometric glucose biosensor was fabricated by immobilization of glucose oxidase on to zinc oxide nanowires. Zinc oxide nanowires with 250-300 nm diameters and approximately 1.2 mu m lengths were grown on the surface of silver wires with a diameter of 250 mu m. Glucose oxidase (GOD) was electrostatically immobilized on the surface of the well aligned zinc oxide nanowires resulting in sensitive, selective, stable and reproducible glucose biosensors. The potentiometric response vs. Ag/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (0.5-1000 mu M) suitable for intracellular glucose detection. By applying a membrane on the sensor the linear range could be extended to 0.5 mu M to 10 mM, which increased the response time from less than 1 to 4s. On the other hand the membrane increased the sensor durability considerably. The sensor response was unaffected by normal concentrations of common interferents with glucose sensing such as uric acid and ascorbic acid.

    Place, publisher, year, edition, pages
    Elsevier Science B.V., Amsterdam., 2010
    Keywords
    Glucose oxidase (GOD), Nafion membrane, Potentiometric biosensor, Electrochemical nanodevices, ZnO nanowires, Fast response
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-55508 (URN)10.1016/j.snb.2009.12.072 (DOI)000276589900039 ()
    Available from: 2010-04-30 Created: 2010-04-30 Last updated: 2017-12-12Bibliographically approved
    2. Glocuse detection with a commercial MOSFET using ZnO nanowires extended gate
    Open this publication in new window or tab >>Glocuse detection with a commercial MOSFET using ZnO nanowires extended gate
    2009 (English)In: IEEE Transaction on Nanotechnology, Vol. 8, no 6, p. 678-683Article in journal (Refereed) Published
    Abstract [en]

    Zinc oxide (ZnO) nanowires were grown on a silver (Ag) wire with a diameter of approximately 250 $mu$m and used in an electrochemical sensor. The enzyme glucose oxidase (GOD) was immobilized on the ZnO nanowires and the silver wire was connected directly to the gate of a MOSFET. Upon exposure to glucose (1-100 $mu$M) the electrochemical response from the glucose oxidase induced a stable measurable voltage change on the gate leading to a strong modulation of the current through the MOSFET. For a sensor with uniform ZnO nanowires functionalized with GOD a fast response time of less than 100 ms, was demonstrated. The effect of the uniformity of the ZnO nanowires on the sensing property was also investigated. The extended gate arrangement facilitated glucose detection in small sample volumes and made it possible to demonstrate the present sensor concept using a standard low threshold MOSFET. The extended gate MOSFET sensor approach demonstrates the possibility and potential of the use of nano-structures coupled to standard electronic components for biosensing applications.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-50566 (URN)10.1109/TNANO.2009.2019958 (DOI)
    Note
    ©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Syed M. Usman Ali, Omer Nour, Magnus Willander and Bengt Danielsson, Glocuse detection with a commercial MOSFET using ZnO nanowires extended gate, 2009, IEEE Transaction on Nanotechnology, (8), 6, 678-683. http://dx.doi.org/10.1109/TNANO.2009.2019958 Available from: 2009-10-12 Created: 2009-10-12 Last updated: 2014-01-15
    3. Functionalised ZnO-nanorod-based selective electrochemical sensor for intracellular glucose
    Open this publication in new window or tab >>Functionalised ZnO-nanorod-based selective electrochemical sensor for intracellular glucose
    Show others...
    2010 (English)In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 25, no 10, p. 2205-2211Article in journal (Refereed) Published
    Abstract [en]

    In this article, we report a functionalised ZnO-nanorod-based selective electrochemical sensor for intracellular glucose. To adjust the sensor for intracellular glucose measurements, we grew hexagonal ZnO nanorods on the tip of a silver-covered borosilicate glass capillary (0.7 mu m diameter) and coated them with the enzyme glucose oxidase. The enzyme-coated ZnO nanorods exhibited a glucose-dependent electrochemical potential difference versus an Ag/AgCl reference microelectrode. The potential difference was linear over the concentration range of interest (0.5-1000 mu M). The measured glucose concentration in human adipocytes or frog oocytes using our ZnO-nanorod sensor was consistent with values of glucose concentration reported in the literature; furthermore, the sensor was able to show that insulin increased the intracellular glucose concentration. This nanoelectrode device demonstrates a simple technique to measure intracellular glucose concentration.

    Place, publisher, year, edition, pages
    Elsevier Science B.V., Amsterdam., 2010
    Keywords
    ZnO nanorods; Functionalisation; Intracellular glucose; Electrochemical sensor
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-58381 (URN)10.1016/j.bios.2010.02.025 (DOI)000278702600004 ()
    Note
    Original Publication: Muhammad Asif, Syed Usman Ali, Omer Nour, Magnus Willander, Cecilia Brännmark, Peter Strålfors, Ulrika Englund, Fredrik Elinder and Bengt Danielsson, Functionalised ZnO-nanorod-based selective electrochemical sensor for intracellular glucose, 2010, Biosensors & bioelectronics, (25), 10, 2205-2211. http://dx.doi.org/10.1016/j.bios.2010.02.025 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2010-08-13 Created: 2010-08-11 Last updated: 2018-01-25
    4. Wireless Remote Monitoring of Glucose Using a Functionalized ZnO Nanowire Arrays Based Sensor
    Open this publication in new window or tab >>Wireless Remote Monitoring of Glucose Using a Functionalized ZnO Nanowire Arrays Based Sensor
    Show others...
    2011 (English)In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 11, no 9, p. 8485-8496Article in journal (Refereed) Published
    Abstract [en]

    This paper presents a prototype wireless remote glucose monitoring system interfaced with a ZnO nanowire arrays-based glucose sensor, glucose oxidase enzyme immobilized onto ZnO nanowires in conjunction with a Nafion (R) membrane coating, which can be effectively applied for the monitoring of glucose levels in diabetics. Global System for Mobile Communications (GSM) services like General Packet Radio Service (GPRS) and Short Message Service (SMS) have been proven to be logical and cost effective methods for gathering data from remote locations. A communication protocol that facilitates remote data collection using SMS has been utilized for monitoring a patients sugar levels. In this study, we demonstrate the remote monitoring of the glucose levels with existing GPRS/GSM network infra-structures using our proposed functionalized ZnO nanowire arrays sensors integrated with standard readily available mobile phones. The data can be used for centralized monitoring and other purposes. Such applications can reduce health care costs and allow caregivers to monitor and support to their patients remotely, especially those located in rural areas.

    Place, publisher, year, edition, pages
    MDPI, 2011
    Keywords
    electrochemical nanosensor, ZnO nanowires, glucose oxidase, Nafion (R) membrane, remote monitoring, data acquisition, Global System for Mobile Communications (GSM)
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-71798 (URN)10.3390/s110908485 (DOI)000295211700017 ()
    Available from: 2011-11-04 Created: 2011-11-04 Last updated: 2017-12-08
    5. Selective potentiometric determination of uric acid with uricase immobilized on ZnO nanowires
    Open this publication in new window or tab >>Selective potentiometric determination of uric acid with uricase immobilized on ZnO nanowires
    Show others...
    2011 (English)In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 152, no 2, p. 241-247Article in journal (Refereed) Published
    Abstract [en]

    In this study, a potentiometric uric acid biosensor was fabricated by immobilization of uricase onto zinc oxide (ZnO) nanowires. Zinc oxide nanowires with 80-150 nm in diameter and 900 nm to 1.5 mu m in lengths were grown on the surface of a gold coated flexible plastic substrate. Uricase was electrostatically immobilized on the surface of well aligned ZnO nanowires resulting in a sensitive, selective, stable and reproducible uric acid biosensor. The potentiometric response of the ZnO sensor vs Ag/AgCl reference electrode was found to be linear over a relatively wide logarithmic concentration range (1-650 mu M) suitable for human blood serum. By applying a Nafion (R) membrane on the sensor the linear range could be extended to 1-1000 mu M at the expense of an increased response time from 6.25 s to less than 9 s. On the other hand the membrane increased the sensor durability considerably. The sensor response was unaffected by normal concentrations of common interferents such as ascorbic acid, glucose, and urea.

    Place, publisher, year, edition, pages
    Elsevier Science B.V., Amsterdam., 2011
    Keywords
    ZnO nanowires, Potentiometric nanosensor, Uricase, Uric acid, Nafion (R), Membrane, Electrochemical nanodevices
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-67542 (URN)10.1016/j.snb.2010.12.015 (DOI)000288877700015 ()
    Note
    Original Publication: Syed Usman Ali, Naveed Ul Hassan Alvi, Zafar Hussain Ibupoto, Omer Nur, Magnus Willander and Bengt Danielsson, Selective potentiometric determination of uric acid with uricase immobilized on ZnO nanowires, 2011, SENSORS AND ACTUATORS B-CHEMICAL, (152), 2, 241-247. http://dx.doi.org/10.1016/j.snb.2010.12.015 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2011-04-18 Created: 2011-04-18 Last updated: 2017-12-11Bibliographically approved
    6. Fabrication and comparative optical characterization of n-ZnO nanostructures (nanowalls, nanorods, nanoflowers and nanotubes)/p-GaN white-light-emitting diodes
    Open this publication in new window or tab >>Fabrication and comparative optical characterization of n-ZnO nanostructures (nanowalls, nanorods, nanoflowers and nanotubes)/p-GaN white-light-emitting diodes
    Show others...
    2011 (English)In: Scripta Materialia, ISSN 1359-6462, E-ISSN 1872-8456, Vol. 64, no 8, p. 697-700Article in journal (Refereed) Published
    Abstract [en]

    White light-emitting diodes (LED) based on ZnO (nanowalls, nanorods, nanoflowers and nanotubes)/p-GaN were fabricated and their electrical, optical and electro-optical characteristics were comparatively characterized. All the LED showed rectifying behavior. The nanowalls and nanorods structures have the highest photoluminescence emission intensity in the visible and UV (at 3.29 eV) regions, respectively. The nanowalls have the highest color rendering index, with a value of 95, and the highest electroluminescence intensity with peaks approximately centered at 420, 450 nm and broad peak covering the visible region.

    Place, publisher, year, edition, pages
    Elsevier Science B.V., Amsterdam., 2011
    Keywords
    Zinc oxide, Nanostructure, Aqueous chemical growth, Optical properties, Heterojunctions
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-66849 (URN)10.1016/j.scriptamat.2010.11.046 (DOI)000287908300002 ()
    Available from: 2011-03-22 Created: 2011-03-21 Last updated: 2017-12-11Bibliographically approved
  • 1838.
    Ali, Wajid
    et al.
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Mohammed, Shahzaan
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, The Institute of Technology.
    Analyzing Wavelength Conversion and Traffic Grooming in Optical WDM Networks2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Wavelength conversion and traffic grooming have been among the most researched areas and technologies of importance in optical networking. Network performance improves significantly by relaxing the wavelength continuity constraint using wavelength converters and by improving the wavelength utilization using traffic grooming. We have done a literature review that compares the performance of wavelength conversion devices with different traffic grooming devices. This thesis work analyzes the impact of increasing the number of wavelength conversion devices and grooming capable devices using different placement schemes for our proposed network model, traffic loads and link capacities. Deciding the number and location of these devices to be used in a network is equally important. This work has been done through the simulation of different device placement scenarios and the results have been analyzed using connection blocking probability as the performance metric. Our reviews and work, correctly predict the behavior of results as demonstrated by the results of other referred literatures relating to wavelength conversion and traffic grooming.

  • 1839.
    Ali, Yasmin
    et al.
    Linköping University, Department of Culture and Communication, Language and Literature.
    Säberg, Maja
    Linköping University, Department of Culture and Communication, Language and Literature.
    Fostering Students’ Oral Communication Skills in the Second Language Classroom: Främja elevers muntliga kommunikationsförmågor i andraspråksklassrummet2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This   thesis was carried out with data collected from a school in the south of India and written by two students becoming teachers of English. The aim of   this thesis is to find out how a teacher can foster and develop student’s   oral communication skills so that they have the ability, willingness and   confidence to speak English. The thesis is based upon the following research   questions:

    • What   factors, according to the students and teachers, are important for developing   and fostering oral communication skills?
    • What speaking activities did the students   and teacher find important for developing and fostering oral communication skills?

    The main findings of this study showed that the teachers found a comfortable environment,   expansion of vocabulary, letting students choose their own topics and importance of good communication skills important when fostering students’ oral communication skills. The students in this study expressed that choosing topics and feeling comfortable in natural communicative situations was important for the development of their oral communication skills: This study, as well as previous studies, found that a teacher can in fact help students increase both their motivation and confidence by planning lessons revolving around topics that are of interest to students, as well as give them the scope to choose their own topics when practicing oral communication activities. Furthermore, the result for the second research question showed that there were several speaking activities that the teachers and students found important for developing and fostering oral communication skills. Some of these were everyday activities which increased their vocabulary, carrying out speeches that allowed the students to choose topics and role-play, such as debates.

  • 1840.
    Ali, Yasmin
    et al.
    Linköping University, Department of Culture and Communication.
    Säberg, Maja
    Linköping University, Department of Culture and Communication.
    The Effects of ‘Flipping’ a Classroom with the Focus on Teaching English as a Second Language2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This literature review analyses what advantages and disadvantages can be gained by utilizing the flipped classroom method. The Swedish curriculum has been taken into consideration when conducting this review in order to see whether the method is compatible with the aim of the subject of English in the Swedish upper secondary school. Two key principles behind the flipped classroom are ‘active learning’ and ‘student-centered learning’. These key principles have been discussed and contrasted with the terms: ‘passive learning’ and ‘teacher-centered learning’. Acknowledging the fact that it is a challenge to engage students in their own learning as well as have them realize the benefits of doing so, this paper also highlights the advantages of implementing technology tools in the classroom where one can meet the needs of the students of today. The results of this literature review show that there are many advantages when utilizing the flipped classroom method. For example, the flipped classroom creates well-suited environments where discussions can take place, as the in-class activities aim at all students being engaged, applying concepts and sharing ideas. However, the results also show some disadvantages that may come when converting to a flipped classroom. Some of these are that the flipped model takes adjustment time, students need to adapt to the transition to a flipped classroom,and preparing online lessons is time consuming. Furthermore, both students and teachers need to learn how to use the new technology that comes with the flipped classroom model.

  • 1841.
    Ali, Zaheer
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Investigating mechanisms of angiogenesis in health and disease using zebrafish models2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Angiogenesis, the growth of blood vessels from an existing vasculature, can occur by sprouting from preexisting vessels or by vessel splitting (intussusception). Pathological angiogenesis drives choroidal neovascularization (CNV) in age related macular degeneration (AMD) which is commonly restricted under the retinal pigment epithelium (RPE), called occult CNV, but may also involve vessels penetrating through the RPE into the sub-retinal space. Pathological vessels are poorly developed, insufficiently perfused and highly leaky, phenotypes that are considered to drive disease progression and lead to poor prognosis. Currently, a number of anti-angiogenic drugs exists, the majority of which target vascular endothelial factor (VEGF), but although they often are highly beneficial for treating eye diseases in the short-term, they are generally of limited efficacy in other diseases such as cancer, and also have poorer efficacy when used for treatment of eye diseases in the long-term. A better understanding of the mechanisms underlying pathological angiogenesis can generate new targets for treatment leading to development of better drugs for cancer and retinopathies, but perhaps also other angiogenesis-dependent diseases, in the future. In this thesis mechanisms involved in developmental angiogenesis or pathological angiogenesis in the choroid, cornea or melanoma was identified. These findings highlight the need to further elaborate our knowledge related to angiogenesis in different tissues/conditions for a more targeted, and potentially effective treatment of diseases in the future.

    In paper I, we for the first time identified the choriocapillaries (CCs) in adult zebrafish and found that occult CNV could be induced by exposing the fish to severe hypoxia. Interestingly, we found that occult CNV relied on intussusception, involving not only de novo generation of intussusceptive pillars but also a previously poorly understood mechanism called pillar splitting. This involved HIF-VEGF-VEGFR2 signaling and evidence that this also occurred in both rats and humans suffering from AMD suggested that the mechanism was conserved and clinically relevant.

    In contrast, we found in paper II that the development of CCs in the zebrafish relies on sprouting angiogenesis, involve continuous remodeling, and delayed maturation of the vasculature in 2D. The initial development was found to occur by a unique process of tissuewide synchronized vasculogenesis. As expected, VEGFA via VEGFR2 was also critical for the development of these vessels in the zebrafish embryo, but surprisingly this was independent on hypoxia-inducible factor (HIF)-1.

    Inflammatory nuclear factor-kB (NF-kB) signaling is involved in the progression of angiogenesis, but this signaling pathway has mainly been studied in the inflammatory cells and the role of NF-kB in the endothelial cells during angiogenesis is poorly understood. In paper III, we found that blocking NF-kB signaling using a specific IKK2 blocker IMD0354, specifically blocks pathological as well as developmental angiogenesis by targeting endothelial cell NF-kB signaling in the endothelial cells. Using a rat model for suture-induced corneal neovascularization, IMD0354 treatment lead to reduced production of inflammatory C-C motif chemokine ligand 2 (CCL2), C-X-C motif chemokine ligand 5 (CXCL5) and VEGF, and thereby reduced pathological corneal angiogenesis in this model.

    Using the zebrafish tumor xenograft model in paper IV, we found an association between Microphthalmia associated transcription factor (MITF) and pigment epithelium derived factor (PEDF), which was involved in pathological tumor angiogenesis and metastasis. Similarly, in paper V we used zebrafish transplantation models to study and investigate the use of biocompatible polymers for the delivery of pro-angiogenic FGF-2 as a potential treatment strategy for ischemic diseases such as myocardial infarction (MI). Conclusively, this thesis provides new insights into diverse fields of angiogenic assays using zebrafish, and reveals new mechanisms of angiogenesis in health and disease. This work will hopefully provide a foundation for further studies into occult CNV related to AMD, a process that has not been possible to study previously in pre-clinical models. In addition, zebrafish xenograft or other transplantation models used in this work will likely be important to study cancer biology and to develop more attractive pharmaceutical preparations based on biocompatible hydrogels formulated as microspheres in the future.

    List of papers
    1. Selective IKK2 inhibitor IMD0354 disrupts NF-kappa B signaling to suppress corneal inflammation and angiogenesis
    Open this publication in new window or tab >>Selective IKK2 inhibitor IMD0354 disrupts NF-kappa B signaling to suppress corneal inflammation and angiogenesis
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    2018 (English)In: Angiogenesis, ISSN 0969-6970, E-ISSN 1573-7209, Vol. 21, no 2, p. 267-285Article in journal (Refereed) Published
    Abstract [en]

    Corneal neovascularization is a sight-threatening condition caused by angiogenesis in the normally avascular cornea. Neovascularization of the cornea is often associated with an inflammatory response, thus targeting VEGF-A alone yields only a limited efficacy. The NF-kappa B signaling pathway plays important roles in inflammation and angiogenesis. Here, we study consequences of the inhibition of NF-kappa B activation through selective blockade of the IKK complex I kappa B kinase beta (IKK2) using the compound IMD0354, focusing on the effects of inflammation and pathological angiogenesis in the cornea. In vitro, IMD0354 treatment diminished HUVEC migration and tube formation without an increase in cell death and arrested rat aortic ring sprouting. In HUVEC, the IMD0354 treatment caused a dose-dependent reduction in VEGF-A expression, suppressed TNF alpha-stimulated expression of chemokines CCL2 and CXCL5, and diminished actin filament fibers and cell filopodia formation. In developing zebrafish embryos, IMD0354 treatment reduced expression of Vegf-a and disrupted retinal angiogenesis. In inflammation-induced angiogenesis in the rat cornea, systemic selective IKK2 inhibition decreased inflammatory cell invasion, suppressed CCL2, CXCL5, Cxcr2, and TNF-alpha expression and exhibited anti-angiogenic effects such as reduced limbal vessel dilation, reduced VEGF-A expression and reduced angiogenic sprouting, without noticeable toxic effect. In summary, targeting NF-kappa B by selective IKK2 inhibition dampened the inflammatory and angiogenic responses in vivo by modulating the endothelial cell expression profile and motility, thus indicating an important role of NF-kappa B signaling in the development of pathologic corneal neovascularization.

    Place, publisher, year, edition, pages
    Springer Netherlands, 2018
    Keywords
    Cornea; Neovascularization; NF-kappa B; IMD0354; IKK2; VEGF
    National Category
    Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-147373 (URN)10.1007/s10456-018-9594-9 (DOI)000428924500007 ()29332242 (PubMedID)2-s2.0-85041334437 (Scopus ID)
    Note

    Funding Agencies|Swedish Research Council [2012-2472]; Swedish Foundation Stiftelsen Synframjandets Forskningsfond/Ogonfonden; Svenska Sallskapet for Medicinsk Forskning; Linkoping Universitet; Jeanssons Stiftelser

    Available from: 2018-05-18 Created: 2018-05-18 Last updated: 2019-05-01Bibliographically approved
    2. Regulatory and Functional Connection of Microphthalmia-Associated Transcription Factor and Anti-Metastatic Pigment Epithelium Derived Factor in Melanoma
    Open this publication in new window or tab >>Regulatory and Functional Connection of Microphthalmia-Associated Transcription Factor and Anti-Metastatic Pigment Epithelium Derived Factor in Melanoma
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    2014 (English)In: Neoplasia, ISSN 1522-8002, E-ISSN 1476-5586, Vol. 16, no 6, p. 529-542Article in journal (Refereed) Published
    Abstract [en]

    Pigment epithelium-derived factor (PEDF), a member of the serine protease inhibitor superfamily, has potent anti-metastatic effects in cutaneous melanoma through its direct actions on endothelial and melanoma cells. Here we show that PEDF expression positively correlates with microphthalmia-associated transcription factor ( MITF) in melanoma cell lines and human samples. High PEDF and MITF expression is characteristic of low aggressive melanomas classified according to molecular and pathological criteria, whereas both factors are decreased in senescent melanocytes and naevi. Importantly, MITF silencing down-regulates PEDF expression in melanoma cell lines and primary melanocytes, suggesting that the correlation in the expression reflects a causal relationship. In agreement, analysis of Chromatin immunoprecipitation coupled to high throughput sequencing (ChIP-seq) data sets revealed three MITF binding regions within the first intron of SERPINF1, and reporter assays demonstrated that the binding of MITF to these regions is sufficient to drive transcription. Finally, we demonstrate that exogenous PEDF expression efficiently halts in vitro migration and invasion, as well as in vivo dissemination of melanoma cells induced by MITF silencing. In summary, these results identify PEDF as a novel transcriptional target of MITF and support a relevant functional role for the MITF-PEDF axis in the biology of melanoma.

    Place, publisher, year, edition, pages
    Neoplasia, 2014
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-110497 (URN)10.1016/j.neo.2014.06.001 (DOI)000340553600007 ()25030625 (PubMedID)
    Note

    Funding Agencies|Ministerio de Ciencia y Competitividad of Spain [SAF-2010-19256, SAF-2011-24225, SAF-2012-32117, FIS 11/02568, RD09/0076/0101, PT13/0010/0012, PI12/01552]; LiU-Cancer; Svenska Sallskapet for Medicinsk Forskning; Ake Wibergs Stiftelse; Goesta Fraenkels Stifelse; Fundacion Cientifica de la Asociacion Espanola Contra el Cancer

    Available from: 2014-09-15 Created: 2014-09-12 Last updated: 2018-12-07
    3. Adjustable delivery of pro-angiogenic FGF-2 by alginate: collagen microspheres
    Open this publication in new window or tab >>Adjustable delivery of pro-angiogenic FGF-2 by alginate: collagen microspheres
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    2018 (English)In: BIOLOGY OPEN, ISSN 2046-6390, Vol. 7, no 3, article id UNSP bio027060Article in journal (Refereed) Published
    Abstract [en]

    Therapeutic induction of blood vessel growth (angiogenesis) in ischemic tissues holds great potential for treatment of myocardial infarction and stroke. Achieving sustained angiogenesis and vascular maturation has, however, been highly challenging. Here, we demonstrate that alginate: collagen hydrogels containing therapeutic, pro-angiogenic FGF-2, and formulated as microspheres, is a promising and clinically relevant vehicle for therapeutic angiogenesis. By titrating the amount of readily dissolvable and degradable collagen with more slowly degradable alginate in the hydrogel mixture, the degradation rates of the biomaterial controlling the release kinetics of embedded proangiogenic FGF-2 can be adjusted. Furthermore, we elaborate a microsphere synthesis protocol allowing accurate control over sphere size, also a critical determinant of degradation/release rate. As expected, alginate: collagen microspheres were completely biocompatible and did not cause any adverse reactions when injected in mice. Importantly, the amount of pro-angiogenic FGF-2 released from such microspheres led to robust induction of angiogenesis in zebrafish embryos similar to that achieved by injecting FGF-2-releasing cells. These findings highlight the use of microspheres constructed from alginate: collagen hydrogels as a promising and clinically relevant delivery system for pro-angiogenic therapy.

    Place, publisher, year, edition, pages
    COMPANY OF BIOLOGISTS LTD, 2018
    Keywords
    Hydrogels; Microspheres; Angiogenesis; Vasculature; Zebrafish
    National Category
    Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-147419 (URN)10.1242/bio.027060 (DOI)000429100500002 ()29449216 (PubMedID)
    Note

    Funding Agencies|Svenska Sallskapet for Medicinsk Forskning; Ake-Wiberg Foundation; Goesta Fraenkel Foundation; Ahrens Stiftelse; Ollie och Elof Ericssons Stiftelse; Carmen och Bertil Ragners Stiftelse; KI Stiftelser och fonder; Loo och Hans Ostermans Stiftelse for Medicinsk Forskning; Vetenskapsradet; Linkoping University

    Available from: 2018-05-17 Created: 2018-05-17 Last updated: 2018-12-07
  • 1842.
    Ali, Zaheer
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Islam, Anik
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sherrell, Peter
    Imperial Coll London, England.
    Le-Moine, Mark
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering.
    Lolas, Georgios
    Univ Athens, Greece.
    Syrigos, Konstantinos
    Univ Athens, Greece.
    Rafat, Mehrdad
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering.
    Jensen, Lasse
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pharmacology.
    Adjustable delivery of pro-angiogenic FGF-2 by alginate: collagen microspheres2018In: BIOLOGY OPEN, ISSN 2046-6390, Vol. 7, no 3, article id UNSP bio027060Article in journal (Refereed)
    Abstract [en]

    Therapeutic induction of blood vessel growth (angiogenesis) in ischemic tissues holds great potential for treatment of myocardial infarction and stroke. Achieving sustained angiogenesis and vascular maturation has, however, been highly challenging. Here, we demonstrate that alginate: collagen hydrogels containing therapeutic, pro-angiogenic FGF-2, and formulated as microspheres, is a promising and clinically relevant vehicle for therapeutic angiogenesis. By titrating the amount of readily dissolvable and degradable collagen with more slowly degradable alginate in the hydrogel mixture, the degradation rates of the biomaterial controlling the release kinetics of embedded proangiogenic FGF-2 can be adjusted. Furthermore, we elaborate a microsphere synthesis protocol allowing accurate control over sphere size, also a critical determinant of degradation/release rate. As expected, alginate: collagen microspheres were completely biocompatible and did not cause any adverse reactions when injected in mice. Importantly, the amount of pro-angiogenic FGF-2 released from such microspheres led to robust induction of angiogenesis in zebrafish embryos similar to that achieved by injecting FGF-2-releasing cells. These findings highlight the use of microspheres constructed from alginate: collagen hydrogels as a promising and clinically relevant delivery system for pro-angiogenic therapy.

  • 1843.
    Ali, Zaheer
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Mukwaya, Anthonny
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Biesemeier, Antje
    Univ Tubingen, Germany.
    Ntzouni, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Ramskold, Daniel
    Karolinska Inst, Sweden.
    Giatrellis, Sarantis
    Karolinska Inst, Sweden.
    Mammadzada, Parviz
    Karolinska Inst, Sweden.
    Cao, Renhai
    Karolinska Inst, Sweden.
    Lennikov, Anton
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Univ Missouri, MO 65211 USA.
    Marass, Michele
    Max Planck Inst Lung and Heart Res, Germany.
    Gerri, Claudia
    Max Planck Inst Lung and Heart Res, Germany.
    Hildesjö, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Clinical pathology.
    Taylor, Michael
    Univ Wisconsin, WI 53706 USA.
    Deng, Qiaolin
    Karolinska Inst, Sweden.
    Peebo, Beatrice
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Ophthalmology in Linköping. Bayer AB, Sweden.
    del Peso, Luis
    Universidad Autónoma de Madrid, Spain; Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM Madrid, Spain.
    Kvanta, Anders
    Karolinska Inst, Sweden.
    Sandberg, Rickard
    Karolinska Inst, Sweden.
    Schraermeyer, Ulrich
    Univ Tubingen, Germany.
    Andre, Helder
    Karolinska Inst, Sweden.
    Steffensen, John F.
    Univ Copenhagen, Denmark.
    Lagali, Neil
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Ophthalmology in Linköping.
    Cao, Yihai
    Karolinska Inst, Sweden.
    Kele, Julianna
    Karolinska Inst, Sweden.
    Jensen, Lasse
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pharmacology. Univ Autonoma Madrid, Spain; UAM, Spain.
    Intussusceptive Vascular Remodeling Precedes Pathological Neovascularization2019In: Arteriosclerosis, Thrombosis and Vascular Biology, ISSN 1079-5642, E-ISSN 1524-4636, Vol. 39, no 7, p. 1402-1418Article in journal (Refereed)
    Abstract [en]

    Objective—

    Pathological neovascularization is crucial for progression and morbidity of serious diseases such as cancer, diabetic retinopathy, and age-related macular degeneration. While mechanisms of ongoing pathological neovascularization have been extensively studied, the initiating pathological vascular remodeling (PVR) events, which precede neovascularization remains poorly understood. Here, we identify novel molecular and cellular mechanisms of preneovascular PVR, by using the adult choriocapillaris as a model.

    Approach and Results—

    Using hypoxia or forced overexpression of VEGF (vascular endothelial growth factor) in the subretinal space to induce PVR in zebrafish and rats respectively, and by analyzing choriocapillaris membranes adjacent to choroidal neovascular lesions from age-related macular degeneration patients, we show that the choriocapillaris undergo robust induction of vascular intussusception and permeability at preneovascular stages of PVR. This PVR response included endothelial cell proliferation, formation of endothelial luminal processes, extensive vesiculation and thickening of the endothelium, degradation of collagen fibers, and splitting of existing extravascular columns. RNA-sequencing established a role for endothelial tight junction disruption, cytoskeletal remodeling, vesicle- and cilium biogenesis in this process. Mechanistically, using genetic gain- and loss-of-function zebrafish models and analysis of primary human choriocapillaris endothelial cells, we determined that HIF (hypoxia-induced factor)-1α-VEGF-A-VEGFR2 signaling was important for hypoxia-induced PVR.

    Conclusions—

    Our findings reveal that PVR involving intussusception and splitting of extravascular columns, endothelial proliferation, vesiculation, fenestration, and thickening is induced before neovascularization, suggesting that identifying and targeting these processes may prevent development of advanced neovascular disease in the future.

    Visual Overview—

    An online visual overview is available for this article.

  • 1844.
    Alici, Gursel
    et al.
    School of Mechanical, Materials, and Mechatronic Engineering, ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Wollongong, Australia.
    Mutlu, Rahim
    School of Mechanical, Materials, and Mechatronic Engineering, ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Wollongong, Australia.
    Melling, Daniel
    Institute for Medical Science and Technology, University of Dundee, Dundee, UK.
    Jager, Edwin
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering.
    Kaneto, Keiichi
    Kyushu Institute of Technology, Eamex Co. Ltd, Chuoku, Fukuoka, Japan.
    Conducting Polymers as EAPs: Device Configurations2016In: Electromechanically Active Polymers: A Concise Reference / [ed] Federico Carpi, Cham: Springer, 2016, p. 257-292Chapter in book (Other academic)
    Abstract [en]

    This chapter focuses on device configurations based on conjugated polymer transducers. After the actuation and sensing configurations in the literature are presented, some successful device configurations are reviewed, and a detailed account of their operation principles is described. The chapter is concluded with critical research issues. With reference to the significant progress made in the field of EAP transducers in the last two decades, there is an increasing need to change our approach to the establishment of new device configurations, novel device concepts, and cutting-edge applications. To this aim, we should start from the performance specifications and end up with the material synthesis conditions and properties which will meet the performance specifications (top-to-down approach). The question should be “what electroactive material or materials can be used for a specific purpose or application,” rather than looking for an application or a device concept suitable to the unique properties of the EAPs and transducers already made of these materials. The field is mature enough to undertake this paradigm change.

  • 1845.
    Alickovic, Emina
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Kevric, Jasmin
    Int Burch University, Bosnia and Herceg.
    Subasi, Abdulhamit
    Effat University, Saudi Arabia.
    Performance evaluation of empirical mode decomposition, discrete wavelet transform, and wavelet packed decomposition for automated epileptic seizure detection and prediction2018In: Biomedical Signal Processing and Control, ISSN 1746-8094, E-ISSN 1746-8108, Vol. 39, p. 94-102Article in journal (Refereed)
    Abstract [en]

    This study proposes a new model which is fully specified for automated seizure onset detection and seizure onset prediction based on electroencephalography (EEG) measurements. We processed two archetypal EEG databases, Freiburg (intracranial EEG) and CHB-MIT (scalp EEG), to find if our model could outperform the state-of-the art models. Four key components define our model: (1) multiscale principal component analysis for EEG de-noising, (2) EEG signal decomposition using either empirical mode decomposition, discrete wavelet transform or wavelet packet decomposition, (3) statistical measures to extract relevant features, (4) machine learning algorithms. Our model achieved overall accuracy of 100% in ictal vs. inter-ictal EEG for both databases. In seizure onset prediction, it could discriminate between inter-ictal, pre-ictal, and ictal EEG with the accuracy of 99.77%, and between inter-ictal and pre-ictal EEG states with the accuracy of 99.70%. The proposed model is general and should prove applicable to other classification tasks including detection and prediction regarding bio-signals such as EMG and ECG. (C) 2017 Elsevier Ltd. All rights reserved.

  • 1846.
    Alickovic, Emina
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Lunner, Thomas
    Linköping University, The Swedish Institute for Disability Research. Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Eriksholm Research Centre, Oticon A/S, 20 Rortangvej, Snekkersten, Denmark.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    A System Identification Approach to Determining Listening Attention from EEG Signals2016In: 2016 24TH EUROPEAN SIGNAL PROCESSING CONFERENCE (EUSIPCO), IEEE , 2016, p. 31-35Conference paper (Refereed)
    Abstract [en]

    We still have very little knowledge about how ourbrains decouple different sound sources, which is known assolving the cocktail party problem. Several approaches; includingERP, time-frequency analysis and, more recently, regression andstimulus reconstruction approaches; have been suggested forsolving this problem. In this work, we study the problem ofcorrelating of EEG signals to different sets of sound sources withthe goal of identifying the single source to which the listener isattending. Here, we propose a method for finding the number ofparameters needed in a regression model to avoid overlearning,which is necessary for determining the attended sound sourcewith high confidence in order to solve the cocktail party problem.

  • 1847.
    Alickovic, Emina
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering. Oticon AS, Denmark.
    Lunner, Thomas
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering. Linköping University, The Swedish Institute for Disability Research. Oticon AS, Denmark; Tech Univ Denmark, Denmark.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    A Tutorial on Auditory Attention Identification Methods2019In: Frontiers in Neuroscience, ISSN 1662-4548, E-ISSN 1662-453X, Vol. 13, article id 153Article in journal (Refereed)
    Abstract [en]

    Auditory attention identification methods attempt to identify the sound source of a listeners interest by analyzing measurements of electrophysiological data. We present a tutorial on the numerous techniques that have been developed in recent decades, and we present an overview of current trends in multivariate correlation-based and model-based learning frameworks. The focus is on the use of linear relations between electrophysiological and audio data. The way in which these relations are computed differs. For example, canonical correlation analysis (CCA) finds a linear subset of electrophysiological data that best correlates to audio data and a similar subset of audio data that best correlates to electrophysiological data. Model-based (encoding and decoding) approaches focus on either of these two sets. We investigate the similarities and differences between these linear model philosophies. We focus on (1) correlation-based approaches (CCA), (2) encoding/decoding models based on dense estimation, and (3) (adaptive) encoding/decoding models based on sparse estimation. The specific focus is on sparsity-driven adaptive encoding models and comparing the methodology in state-of-the-art models found in the auditory literature. Furthermore, we outline the main signal processing pipeline for how to identify the attended sound source in a cocktail party environment from the raw electrophysiological data with all the necessary steps, complemented with the necessary MATLAB code and the relevant references for each step. Our main aim is to compare the methodology of the available methods, and provide numerical illustrations to some of them to get a feeling for their potential. A thorough performance comparison is outside the scope of this tutorial.

  • 1848.
    Alickovic, Emina
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Subasi, Abdulhamit
    Effat Univ, Saudi Arabia.
    Ensemble SVM Method for Automatic Sleep Stage Classification2018In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 67, no 6, p. 1258-1265Article in journal (Refereed)
    Abstract [en]

    Sleep scoring is used as a diagnostic technique in the diagnosis and treatment of sleep disorders. Automated sleep scoring is crucial, since the large volume of data should be analyzed visually by the sleep specialists which is burdensome, time-consuming tedious, subjective, and error prone. Therefore, automated sleep stage classification is a crucial step in sleep research and sleep disorder diagnosis. In this paper, a robust system, consisting of three modules, is proposed for automated classification of sleep stages from the single-channel electroencephalogram (EEG). In the first module, signals taken from Pz-Oz electrode were denoised using multiscale principal component analysis. In the second module, the most informative features are extracted using discrete wavelet transform (DWT), and then, statistical values of DWT subbands are calculated. In the third module, extracted features were fed into an ensemble classifier, which can be called as rotational support vector machine (RotSVM). The proposed classifier combines advantages of the principal component analysis and SVM to improve classification performances of the traditional SVM. The sensitivity and accuracy values across all subjects were 84.46% and 91.1%, respectively, for the five-stage sleep classification with Cohens kappa coefficient of 0.88. Obtained classification performance results indicate that, it is possible to have an efficient sleep monitoring system with a single-channel EEG, and can be used effectively in medical and home-care applications.

  • 1849.
    Alickovic, Emina
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Subasi, Abdulhamit
    Effat University, Saudi Arabia.
    Medical Decision Support System for Diagnosis of Heart Arrhythmia using DWT and Random Forests Classifier2016In: Journal of medical systems, ISSN 0148-5598, E-ISSN 1573-689X, Vol. 40, no 4, p. 108-Article in journal (Refereed)
    Abstract [en]

    In this study, Random Forests (RF) classifier is proposed for ECG heartbeat signal classification in diagnosis of heart arrhythmia. Discrete wavelet transform (DWT) is used to decompose ECG signals into different successive frequency bands. A set of different statistical features were extracted from the obtained frequency bands to denote the distribution of wavelet coefficients. This study shows that RF classifier achieves superior performances compared to other decision tree methods using 10-fold cross-validation for the ECG datasets and the obtained results suggest that further significant improvements in terms of classification accuracy can be accomplished by the proposed classification system. Accurate ECG signal classification is the major requirement for detection of all arrhythmia types. Performances of the proposed system have been evaluated on two different databases, namely MIT-BIH database and St. -Petersburg Institute of Cardiological Technics 12-lead Arrhythmia Database. For MIT-BIH database, RF classifier yielded an overall accuracy 99.33 % against 98.44 and 98.67 % for the C4.5 and CART classifiers, respectively. For St. -Petersburg Institute of Cardiological Technics 12-lead Arrhythmia Database, RF classifier yielded an overall accuracy 99.95 % against 99.80 % for both C4.5 and CART classifiers, respectively. The combined model with multiscale principal component analysis (MSPCA) de-noising, discrete wavelet transform (DWT) and RF classifier also achieves better performance with the area under the receiver operating characteristic (ROC) curve (AUC) and F- measure equal to 0.999 and 0.993 for MIT-BIH database and 1 and 0.999 for and St. Petersburg Institute of Cardiological Technics 12-lead Arrhythmia Database, respectively. Obtained results demonstrate that the proposed system has capacity for reliable classification of ECG signals, and to assist the clinicians for making an accurate diagnosis of cardiovascular disorders (CVDs).

  • 1850.
    Alila, Patrick
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    Complementing network security to the ISO/IEC 27000 standard2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I syfte att öppna upp nya affärsmöjligheter för informationssäkerhetsföretaget Secure State AB, har detta arbete bedrivits för att komplettera företagets nuvarande standard för informationssäkerhetsarbete med ytterligare nätverkssäkerhet.

    Krav på slutresultatet var att dokumentet eller standarden skulle kunna komplettera ISO 27000, samt vara kostnadseffektivt.

    Efter en undersökning av den nämnda standarden konstaterades att enbart ISO 27000 i sig inte är ett fullgott verktyg för nätverkssäkerhetsarbete, på grund av dess icke-tekniska inriktning och målgrupp.

    Att komplettera ISO 27000 med av författaren utarbetade krav var inte heller att föredra, då syftet med ett standardiserat arbetssätt därmed försvinner. Det är bättre och attraktivare för kunden att använda sig av specifika tekniska standarder och rekommendationer.

    Sökandet efter en kompletterande standard påbörjades däför enligt dessa kriterier

    Kompatibilitet med ISO 27000

    Teknisk inriktning

    Kostnadseffektiv

    Attraktiv att arbeta efter

    ISO 18028 uppfyller dessa krav mycket bra på samtliga punkter och är därmed bäst lämpad att arbeta efter av de tre standarder/rekommendationer som undersöktes mot kravlistan. Därför bör också Secure State välja att utföra nätverkssäkerhetsarbetet förankrat i ISO 18028 med följande förväntade resultat.

    Fig. 10, Förväntat resultat av komplettering till ISO 27000. Högst upp ser vi de allmäna informationssäkerhetspolicies samtliga anställda följer. Som nivå två finns ISO 27000, vilket är ledningens system för hur informationssäkerhetsarbetet övergripande ska hanteras. Längst ned ser vi den tekniska skyddsutrustningen som administreras av tekniker som följer lämpliga dokument. Denna rapport har identifierat ISO 18028 för säkerheten i nätverk, övriga återstår att vid behov identifiera för annan teknisk utrustning.

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