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41.
Sadegh Fattahi Mohammad Karimi Alivije Farhang Babamahmoodi Masomeh Bayani Mahmoud Sadeghi Haddad Zavareh Mohsen Asouri Maryam Lotfi Galia Amirbozorgi Haleh Akhavan-Niaki 《Indian journal of clinical biochemistry : IJCB》2018,33(4):467-472
Hepatitis B virus (HBV) infection is a worldwide health concern which is associated with significant morbidity and mortality. Both viral and host factors have a significant effect on infection, replication and pathogenesis of HBV. The aim of this study was to investigate the effect of CYP2E1 and CYP1A1 genetic variants on susceptibility to HBV. 143 individuals including 54 chronic HBV patients and 89 healthy controls were enrolled in the genotyping procedure. rs2031920 and rs3813867 at CYP2E1 as well as rs4646421 and rs2198843 at CYP1A1 loci were studied in all subjects using PCR–RFLP (restriction fragment length polymorphism) analysis. Both variants at CYP2E1 locus were monomorphic in all studied subjects. Genotype frequency of rs4646421 was significantly different between chronic HBV patients and healthy blood donors (P = 0.04, OR 4.31; 95% CI 1.04–17.7). Furthermore, individuals carrying at least one C allele (CC or CT genotypes) for rs4646421 seemed to have a decrease risk of hepatitis in comparison with TT genotype (P = 0.039). Our results showed a relationship between rs4646421 TT genotype (rare genotype) and the risk for developing chronic HBV infection (four times higher). Further studies are needed to examine the role of CYP1A1 polymorphism in susceptibility to chronic HBV infection. 相似文献
42.
In this paper, new results are established for generating tracking policies in aggregated production-inventory systems. A dynamic model is developed to characterize the evolution of targeted production, inventory and demand over time and incorporates the inventory, production and demand tracking errors as additional variables. The control variables are managerial decision variables on rate of production and advertisement. The developed model takes the form of linear system with time-varying delay. Tracking policies are then formulated and determined to ensure that the production-inventory tracking model achieves a desirable performance in terms of H∞-measure. Numerical simulation is performed to illustrate the theoretical developments. 相似文献
43.
Tshering C. Dorji El-sayed Atlam Susumu Yata Mahmoud Rokaya Masao Fuketa Kazuhiro Morita Jun-ichi Aoe 《Information processing & management》2010
Minimal Prefix (MP) double array is an efficient data structure for a trie. However, its space efficiency is degraded by the non-compact management of suffixes. This paper presents three methods to compress the MP double array. The first two methods compress the MP double array by accommodating short suffixes inside the leaf nodes, and pruning leaf nodes corresponding to the end marker symbol. These methods achieve size reduction of up to 20%, making insertion and deletion faster at the same time while maintaining the retrieval time of O(1). The third method eliminates empty spaces in the array that holds suffixes, and improves the maximum size reduction further by about 5% at the cost of increased insertion time. Compared to a Ternary Search Tree, the key retrieval of the compressed MP double array is 50% faster and its size is 3–5 times smaller. 相似文献
44.
Research has documented overlapping and coexisting characteristics of learning disabilities (LD) and emotional and behavioural difficulties (EBD). Such concomitance may impact teacher referrals of children at risk for LD which in turn may influence service delivery. Using the Learning Disabilities Diagnostic Inventory (LDDI) and the Strengths and Difficulties Questionnaire (SDQ), we examined teachers’ ratings of EBD and LD symptoms in 439 students referred for LD in elementary schools in Oman. A multivariate analysis of variance (MANOVA) showed that there were no gender differences in LD symptoms, whereas there were significant gender differences in teachers’ ratings of hyperactivity and conduct problems in referred children. There was an association between teachers’ ratings on the LDDI and SDQ dimensions, reflecting children’s concurrent display of LD and EBD symptoms. Implications are discussed within an Omani context in which there is a need to increase teachers’ awareness of the behavioural and emotional profile of children at risk for LD. 相似文献
45.
Manouchehr Tabatabaei Alison Solomon Emily Strickland Eddie Metrejean 《The American journal of distance education》2013,27(3):196-206
The main focus of this research is on perceptions of accounting employers of those individuals obtaining their accounting education online. An online survey of accounting professionals was conducted, and the findings suggest that a candidate with a traditional education is more suitable for employment than a candidate with an online education. Also, the reputation of the candidate’s institution, as well as the candidate’s grade point average and work experience, all have an impact on an employer’s hiring decision. However, the perception of respondents is that online education is becoming more acceptable. Further, the online education experience of recruiters does not impact their hiring decisions. 相似文献
46.
Hawamdeh Mahmoud Altınay Zehra Altınay Fahriye Arnavut Ahmet Ozansoy Kezban Adamu Idris 《Education and Information Technologies》2022,27(5):6037-6068
Education and Information Technologies - The COVID-19 pandemic increase the use of distance learning while studies have shown that there is insufficient digital knowledge among students in distance... 相似文献
47.
This paper aims to solve scaled consensus problem for general linear multiagent systems under denial-of-service (DoS) attacks. Firstly, we propose a new scaled disagreement vector and investigate its properties under switching and undirected graphs. Secondly, we establish sufficient conditions in terms of linear matrix inequalities in order to guarantee that the multiagent system achieves scaled consensus under DoS attacks. Contrary to most existing studies where DoS attacks on all the channels are same, in this note, we formulate the problem such that the adversary compromises each agent independently. Moreover, the distributed consensus protocol is investigated for networks with time-varying delay. Finally, two simulation examples are given to demonstrate effectiveness of the proposed design methodologies. 相似文献
48.
In this paper, new results are established for the delay-independent and delay-dependent problems of dissipative analysis and state-feedback synthesis for a class of nonlinear systems with time-varying delays with polytopic uncertainties. This class consists of linear time-delay systems subject to nonlinear cone-bounded perturbations. Both delay-independent and delay-dependent dissipativity criteria are established as linear matrix inequality-based feasibility tests. The developed results in this paper for the nominal system encompass available results on H∞ approach, passivity and positive realness for time-delay systems as special cases. All the sufficient stability conditions are cast. Robust dissipativity as well as dissipative state-feedback synthesis results are also derived. Numerical examples are provided to illustrate the theoretical developments. 相似文献
49.
Zhengrong Xiang Changhui Qiao Magdi S. Mahmoud 《Journal of The Franklin Institute》2012,349(3):1213-1230
This paper investigates the problem of robust H∞ filtering for switched stochastic systems under asynchronous switching. The so-called asynchronous switching means that the switching between the filters and system modes is asynchronous. The aim is to design a filter ensuring robust exponential mean square stability and a prescribed H∞ performance level for the filtering error systems. Based on the average dwell time approach and piecewise Lyapunov functional technique, sufficient conditions for the existence of the robust H∞ filter are derived, and the proposed filter can be obtained by solving a set of LMIs(linear matrix inequalities). Finally, a numerical example is given to show the effectiveness of the proposed approach. 相似文献
50.
Where Arab social science and humanities scholars choose to publish: Falling in the predatory journals trap
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The purpose of this paper is to report the findings of a study of publishing behaviour among a group of Arab scholars in social science and humanities disciplines. The paper also investigated the number of Arab scholars who are publishing in predatory journals and the reasons that drive them to select these journals to share their scholarly findings. The study adopted a mixed methods approach. Eighteen journals that were categorized as predatory journals were scanned to find the number of Arab scholars who published in them. Then, a questionnaire was sent to Egyptian and Saudi scholars as they were found to be the top Arab contributors in these journals. The questionnaire was followed by semi‐structured interviews to gain an in‐depth understanding of the publishing behaviour. The data showed that many Arab scholars prefer publishing in predatory journals as these journals are easier and faster. The results also indicate that there is a need to raise the awareness of the harm that predatory journals can cause to the scholars and how they can avoid these journals. This study was conducted with social science and humanities scholars in Egypt and Saudi Arabia. The publishing behaviour may differ in other scholarly disciplines and other Arabic countries. 相似文献