375 research outputs found

    Understanding mechanisms of Ketamine-induced human urinary tract damage

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    Ketamine is a phencyclidine derivative N-Methyl D-Aspartate (NMDA) receptor antagonist used as an anaesthetic and analgesic. A florid non-bacterial cystitis condition known as ketamine-induced cystitis (KIC) has recently been reported in abusers and prescription users of ketamine. Whilst the aetiological agent in patients withKIC is known, the mechanism of disease development is unknown. The aims of this study were to investigate the potential mechanisms of development of KIC and to establish potential links between KIC and other chronic non-bacterial cystitis conditions; interstitial cystitis (IC) and eosinophilic cystitis (EC). These aims were pursued under the following objectives; 1. Investigate toxicity of ketamine and its primary metabolite nor-ketamine on normal human urothelial (NHU) cell cultures. 2. Describe human urothelial tissue damage caused by ketamine. 3. Assess a possible relationship between ketamine exposure and development of KIC. The main findings were that; Ketamine and nor-ketamine were equally toxic to NHU cells in a concentration dependent manner. A specific NMDA receptor antagonist (MK-801) did not show any urothelial toxicity on its own but unexpectedly increased toxicity of ketamine when used in combination. Immunolabelling of the three individual KIC tissue sections demonstrated epithelial denudation and stromal inflammation with oedematous blood vessels. Results from a telephone questionnaire did not show any obvious relationship between prescription use of ketamine and development of KIC. Literature review suggested considerable similarities between the reported symptoms and clinical investigation findings of KIC to mainly EC and to some extent to IC. In conclusion, the study indicated that ketamine might cause human urinary tract damage by impairing the barrier function of urothelium, inducing inflammation and resultant development of KIC. These experiments should form the basis for future research in to understanding the mechanisms of development of KIC and other difficult to treat chronic uropathies such as EC and IC

    Core Competencies Required by University Librarians for the Adoption of Information Technology Tools: An Empirical Study

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    Abstract: Purpose: This study explores core competencies that are needed by library professionals for the implementation of Information Technology (IT) Tools in the university library of Lahore, Pakistan. Methodology/Approach: A quantitative approach followed by survey research design was opted to complete the study on the competencies which are needed by library professionals for the implementation of Information Technology (IT) in the university library of Lahore, Pakistan. A total of 120 questionnaires were distributed among university librarians of Lahore. All questionnaires were sent through emails. 91 duly filled questionnaires were received by the researchers from the respondents. The response rate was 75.83%. Research limitation (s): This study is limited to the university library of Lahore, Pakistan. Key finding (s): Results of the study show that Librarians need IT skills for applying the latest technologies in their libraries. They need automation-related skills. They can\u27t bring innovation to their libraries with a traditional mind setup. They need web-based expertise too. Library professionals need to become innovators. They require practical expertise for performing electronic services in their libraries. Library practitioners need to grab a set of learning IT methods to utilize technology. They need to participate in continuous professional development programmes. Practical implication (s): The study recommends competencies that need to be grabbed by library professionals of the universities for implementing Information Communication Technologies (ICTs) in their libraries for providing efficient services to the users and meeting the required objectives of the organization. Emerging technologies should be implemented in the university libraries to fulfill the information and research needs of the users quickly. Contribution to knowledge: Findings and recommendations of the study are very fruitful to adopt the latest tools of Information Technology in the university libraries. Research type: Research Keyword (s): Competencies of universities libraries, IT adoption in university libraries, Required core competencie

    Covert Communication in Fading Channels under Channel Uncertainty

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    A covert communication system under block fading channels is considered where users experience uncertainty about their channel knowledge. The transmitter seeks to hide the covert communication to a private user by exploiting a legitimate public communication link while the warden tries to detect this covert communication by using a radiometer. We derive the exact expression for the radiometers optimal threshold which determines the performance limit of the wardens detector. Furthermore for given transmission outage constraints the achievable rates for legitimate and covert users are analyzed while maintaining a specific level of covertness. Our numerical results illustrate how the achievable performance is affected by the channel uncertainty and required level of covertness.Comment: to appear in IEEE VTC2017-Sprin

    A Pseudo-Worm Daemon (PWD) for empirical analysis of zero-day network worms and countermeasure testing

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    The cyber epidemiological analysis of computer worms has emerged a key area of research in the field of cyber security. In order to understand the epidemiology of computer worms; a network daemon is required to empirically observe their infection and propagation behavior. The same facility can also be employed in testing candidate worm countermeasures. In this paper, we present the architecture and design of Pseudo-Worm Daemon; termed (PWD), which is designed to perform true random scanning and hit-list worm like functionality. The PWD is implemented as a proof-of-concept in C programming language. The PWD is platform independent and can be deployed on any host in an enterprise network. The novelty of this worm daemon includes; its UDP based propagation, a user-configurable random scanning pool, ability to contain a user defined hit-list, authentication before infecting susceptible hosts and efficient logging of time of infection. Furthermore, this paper presents experimentation and analysis of a Pseudo-Witty worm by employing the PWD with real Witty worm outbreak attributes. The results obtained by Pseudo-Witty worm outbreak are quite comparable to real Witty worm outbreak; which are further quantified by using the Susceptible Infected (SI) model

    Towards automated distributed containment of zero-day network worms

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    Worms are a serious potential threat to computer network security. The high potential speed of propagation of worms and their ability to self-replicate make them highly infectious. Zero-day worms represent a particularly challenging class of such malware, with the cost of a single worm outbreak estimated to be as high as US$2.6 Billion. In this paper, we present a distributed automated worm detection and containment scheme that is based on the correlation of Domain Name System (DNS) queries and the destination IP address of outgoing TCP SYN and UDP datagrams leaving the network boundary. The proposed countermeasure scheme also utilizes cooperation between different communicating scheme members using a custom protocol, which we term Friends. The absence of a DNS lookup action prior to an outgoing TCP SYN or UDP datagram to a new destination IP addresses is used as a behavioral signature for a rate limiting mechanism while the Friends protocol spreads reports of the event to potentially vulnerable uninfected peer networks within the scheme. To our knowledge, this is the first implementation of such a scheme. We conducted empirical experiments across six class C networks by using a Slammer-like pseudo-worm to evaluate the performance of the proposed scheme. The results show a significant reduction in the worm infection, when the countermeasure scheme is invoked

    Impact of Teacher Self-Efficacy on Secondary School Students’ Academic Achievement

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    The study of self-efficacy and its impact on human performance has intrigued many scholars during the last two decades, for example, Clayson and Sheffet, 2006; Nauta, 2004; Muijsand Rejnolds 2001; Bandura, 1997 and Soodak and Podell, 1993. This study was conducted with the objective to find out the impact ofteacher self-efficacy on the secondary school students’ academic achievement. For this purpose, sixty (60) secondary school teachers and a hundred (100) secondary school students in Chiltan Town of Quetta city were randomly selected. To collect the data, teacher self-efficacy questionnaire for teachers was used and to measure students’ academic achievement a test was developed. Data were analyzed through Pearson Correlation and Multiple Regressions. The findings of the study revealed that teacher self-efficacy has a positive impact on the students’ academic achievement. The results of the study and their pedagogical implications have been discussed, and recommendations have been provided for further researches

    ORS Status in University Libraries: A Survey

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    The goal of this study was to explore the status of Online Reference Services in the university libraries of Lahore, Pakistan. A quantitative method followed by a survey research design was adopted to gather the required data. The population of the study was all the public and private sector universities of Lahore. The tool of the questionnaire was developed to gather the required data. Accumulated data were gathered through SPSS Software. The findings of the study show that only a few libraries are utilizing online reference services. Library professionals are facing several barriers to the implementation of ORS in university libraries including a lack of adequate planning. The study motivates library professionals to implement ORS in university libraries so that users might be served efficiently through the modern-driven approaches. Old fashioned reference services need to be replaced by the latest online methods in the best interests of both the users and the organization. The study has practical implications for the policymakers, concerned authorities, and top administration of the university libraries

    Impact of Automation on Users’ Perception of Library Services

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    The critical destinations of this study were to inspect the impact of Automation on users\u27 perception of library services at Government College University Faisalabad. The present study has three research objectives including (a)To assess the user\u27s perception regarding library automation at GCU Faisalabad, (b)To check the level of satisfaction of the users regarding library services at GCU Faisalabad, and (e)To measure the problem faced by the users after automation of library services at GCU Faisalabad. To meet the objectives, the investigator used a quantitative research approach and developed a questionnaire for the data collection instrument. The convenience sampling technique was used for collecting data from the target population. There were 16570 students enrolled in BS, Master, M.Phil, and Ph.D. degree programs. The sample size was 391(2.35 % of the total population) students. There were 375 out of 391 students who filled the questionnaire. Hence, the response rate was 95.9 %. The results revealed that more than 75% percent of the participants like to support and use automated library services and hybrid services. Further respondents gave their points of view that they had a trend to use automated services to save time. Moreover, the result of this study revealed that the participants were well aware of the library automated services, offered by GCU libraries. This research points out that most of the total participants were satisfied by the automated services, offered by the GCU library
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