200 research outputs found

    Adaptive fair channel allocation for QoS enhancement in IEEE 802.11 wireless LANs

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    The emerging widespread use of real-time multimedia applications over wireless networks makes the support of quality of service (QoS) a key problem. In this paper, we focus on QoS support mechanisms for IEEE 802.11 wireless ad-hoc networks. First, we review limitations of the upcoming IEEE 802.11e enhanced DCF (EDCF) and other enhanced MAC schemes that have been proposed to support QoS for 802.11 ad-hoc networks. Then, we describe a new scheme called adaptive fair EDCF that extends EDCF, by increasing the contention window during deferring periods when the channel is busy, and by using an adaptive fast backoff mechanism when the channel is idle. Our scheme computes an adaptive backoff threshold for each priority level by taking into account the channel load. The new scheme significantly improves the quality of multimedia applications. Moreover, it increases the overall throughput obtained both in medium and high load cases. Simulution results show that our new scheme outperforms EDCF and other enhanced schemes. Finally, we show that the adaptive fair EDCF scheme achieves a high degree of fairness among applications of the same priority level

    Stigma in youth with Tourette's syndrome: a systematic review and synthesis

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    Tourette's syndrome (TS) is a childhood onset neurodevelopmental disorder, characterised by tics. To our knowledge, no systematic reviews exist which focus on examining the body of literature on stigma in association with children and adolescents with TS. The aim of the article is to provide a review of the existing research on (1) social stigma in relation to children and adolescents with TS, (2) self-stigma and (3) courtesy stigma in family members of youth with TS. Three electronic databases were searched: PsycINFO, PubMed and Web of Science. Seventeen empirical studies met the inclusion criteria. In relation to social stigma in rating their own beliefs and behavioural intentions, youth who did not have TS showed an unfavourable attitude towards individuals with TS in comparison to typically developing peers. Meanwhile, in their own narratives about their lives, young people with TS themselves described some form of devaluation from others as a response to their disorder. Self-degrading comments were denoted in a number of studies in which the children pointed out stereotypical views that they had adopted about themselves. Finally, as regards courtesy stigma, parents expressed guilt in relation to their children's condition and social alienation as a result of the disorder. Surprisingly, however, there is not one study that focuses primarily on stigma in relation to TS and further studies that examine the subject from the perspective of both the 'stigmatiser' and the recipient of stigma are warranted

    PERAN PENGURUS HIMPUNAN MAHASISWA JURUSAN PAI TERHADAP PEMBINAAN AHLAK ANAK BINAAN DI DESA TAENG KECAMATAN PALLANGGA KABUPATEN GOWA

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    Peran pengurus himpunan mahasiswa jurusan dalam pembinaan akhlak anak dapat dilakukan dengan cara membimbing, mengarahkan dan memberi contoh yang baik dan mampu menjadi teladan pada anak. Pembinaan akhlak merupakan hal yang paling penting dan sangat mendesak untuk dilakukan dalam rangka menjaga stabilitas hidup masa depannya. Pembinaan akhlak anak sangat penting karena mengingat secara psikologi usia anak 6-8 tahun adalah usia yang berada dalam goncangan dan mudah terpengaruh sebagai akibat dari keadaan dirinya yang masih belum memiliki bekal pengetahuan, mental dan pengalaman yang cukup. Akibat dari keadaan yang demikian, para anak rentan mudah terjerumus yang menghancurkan masa depannya. Sehingga peran pengurus himpunan mahasiswa jurusan pendidikan agama islam membantu dalam mengarahkan anak untuk masa depannya dalam kehidupan sehari-hari.Kata Kunci: Himpunan Mahasiswa; Organisasi Mahasiswa; Pembinaan Akhlak Anak

    Comparison of Thrombolysis in Myocardial Infarction Score and Heart Score in risk stratification of acute myocardial infarction patients, prognostic accuracy and arrhythmia incidence

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    Background: To compare TIMI & HEART SCORE for their risk stratification in Acute Myocardial Infarction Patients,Ā  prognostic accuracy and Arrhythmia incidence.Methods: This observational study is conducted in a Tertiary care hospital over a period of 2 years from August 2017 to July 2019. A total of 100 patients presented to ER with Chest Pain are selected for study. Patients were monitored for a period of one month in ICCU.Results: In present study out of 61 cases with TIMI score ā‰„5, mortality of 11.5%(7 cases, p value 0.028). Heart score more than 6Ā  constitutes high risk group, out of which mortality was observed in 7.45% cases (p=0.48). Most of the arrhythmias (70.49%) in present study observed in patients with TIMI score ā‰„5 (High risk group) which is statistically significant with p value 0.002. Most of the arrhythmias in present study observed in patients with HS ā‰„8 which is not statistically significant with p value 0.135.Conclusions: In present study, overall mortality rate was 7% and these patients who died constitutes to high risk group with TIMI. HEART SCORE identified more patients as low risk compared to TIMI SCORE. TIMI SCORE is a good predictor of arrhythmia incidence

    Touretteā€™s Is a Lonely Place: an Interpretative Phenomenological Analysis of the Personal Experience and Identity of Adults with Touretteā€™s Syndrome

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    Research suggests that adults with Touretteā€™s syndrome (TS) may face unique challenges in their everyday life due to their condition. To date, however, only a limited number of studies exist in relation to their life experiences and conception of identity. This study, which we believe to be the first of its kind, aimed to expand the literature by ā€˜giving voiceā€™ to this population, and to evaluate the social and personal cost of living with TS during adulthood. Semi-structured interviews were conducted with sixteen adults with Touretteā€™s that focused on how they negotiated their identity and experiences. Transcripts of recorded interviews were subjected to interpretative phenomenological analysis. Three superordinate themes emerged: a) ā€œIncorporating Touretteā€™s syndrome into selfā€ revealed two divergent ways in which TS was merged into the participantsā€™ self-identity, either by reconciling with it or fighting against it; b) ā€œInterpersonal interactionā€ covered issues relating to negative and supportive ties as a result of their condition; and finally, c) ā€œThe solitude of Touretteā€™s syndromeā€ described the loneliness that stems from the condition. The current findings suggest that the experience of the participants is a multidimensional one related to self-identity threat, social withdraw, and self-stigma. Implications for clinical practice on the topic are discussed

    An embedding scheme for the Dirac equation

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    An embedding scheme is developed for the Dirac Hamiltonian H. Dividing space into regions I and II separated by surface S, an expression is derived for the expectation value of H which makes explicit reference to a trial function defined in I alone, with all details of region II replaced by an effective potential acting on S and which is related to the Green function of region II. Stationary solutions provide approximations to the eigenstates of H within I. The Green function for the embedded Hamiltonian is equal to the Green function for the entire system in region I. Application of the method is illustrated for the problem of a hydrogen atom in a spherical cavity and an Au(001)/Ag/Au(001) sandwich structure using basis sets that satisfy kinetic balance.Comment: 16 pages, 5 figure

    Double-Stranded RNA Attenuates the Barrier Function of Human Pulmonary Artery Endothelial Cells

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    Circulating RNA may result from excessive cell damage or acute viral infection and can interact with vascular endothelial cells. Despite the obvious clinical implications associated with the presence of circulating RNA, its pathological effects on endothelial cells and the governing molecular mechanisms are still not fully elucidated. We analyzed the effects of double stranded RNA on primary human pulmonary artery endothelial cells (hPAECs). The effect of natural and synthetic double-stranded RNA (dsRNA) on hPAECs was investigated using trans-endothelial electric resistance, molecule trafficking, calcium (Ca2+) homeostasis, gene expression and proliferation studies. Furthermore, the morphology and mechanical changes of the cells caused by synthetic dsRNA was followed by in-situ atomic force microscopy, by vascular-endothelial cadherin and F-actin staining. Our results indicated that exposure of hPAECs to synthetic dsRNA led to functional deficits. This was reflected by morphological and mechanical changes and an increase in the permeability of the endothelial monolayer. hPAECs treated with synthetic dsRNA accumulated in the G1 phase of the cell cycle. Additionally, the proliferation rate of the cells in the presence of synthetic dsRNA was significantly decreased. Furthermore, we found that natural and synthetic dsRNA modulated Ca2+ signaling in hPAECs by inhibiting the sarco-endoplasmic Ca2+-ATPase (SERCA) which is involved in the regulation of the intracellular Ca2+ homeostasis and thus cell growth. Even upon synthetic dsRNA stimulation silencing of SERCA3 preserved the endothelial monolayer integrity. Our data identify novel mechanisms by which dsRNA can disrupt endothelial barrier function and these may be relevant in inflammatory processes

    Mutation in NSUN2, which Encodes an RNA Methyltransferase, Causes Autosomal-Recessive Intellectual Disability

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    Causes of autosomal-recessive intellectual disability (ID) have, until very recently, been under researched because of the high degree of genetic heterogeneity. However, now that genome-wide approaches can be applied to single multiplex consanguineous families, the identification of genes harboring disease-causing mutations by autozygosity mapping is expanding rapidly. Here, we have mapped a disease locus in a consanguineous Pakistani family affected by ID and distal myopathy. We genotyped family members on genome-wide SNP microarrays and used the data to determine a single 2.5 Mb homozygosity-by-descent (HBD) locus in region 5p15.32ā€“p15.31; we identified the missense change c.2035G>A (p.Gly679Arg) at a conserved residue within NSUN2. This gene encodes a methyltransferase that catalyzes formation of 5-methylcytosine at C34 of tRNA-leu(CAA) and plays a role in spindle assembly during mitosis as well as chromosome segregation. In mouse brains, we show that NSUN2 localizes to the nucleolus of Purkinje cells in the cerebellum. The effects of the mutation were confirmed by the transfection of wild-type and mutant constructs into cells and subsequent immunohistochemistry. We show that mutation to arginine at this residue causes NSUN2 to fail to localize within the nucleolus. The ID combined with a unique profile of comorbid features presented here makes this an important genetic discovery, and the involvement of NSUN2 highlights the role of RNA methyltransferase in human neurocognitive development
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