89 research outputs found

    Energy Efficient Handover Management in Cluster Based Wireless Sensor Network

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    Wireless sensors are compact-size, low power, inexpensive devices which are capable to measure local environmental conditions or other parameters such as temperature, acceleration, and forward such information to a sink for proper processing. Wireless sensor networks (WSNs) have been under development by both academic and industrial societies for a while. By moving toward applications such as the area of medical care and disaster response mobility in wireless sensor networks has attracted a lot of attentions. In energy constraint sensor network, mobility handling introduces unique challenges in aspects like resource management, coverage, routing protocols, security, etc. This paper, proposes an energy-efficient mobility-aware MAC protocol to handle node handover among different clusters. The simulation-based experiments show that the proposed protocol has better performance compared to the existing S-MAC method

    Deficiência combinada de 17α-hidroxilase/17,20 liase devido à mutação p.R96W no gene CYP17 em um paciente brasileiro

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    Congenital adrenal hyperplasia (CAH) resulting from 17α-hydroxylase/17,20-lyase deficiency is a rare autosomal recessive disease and the second most common form of CAH in Brazil. We describe the case of a Brazilian patient with CYP17 deficiency (17α-hydroxylase/17,20-lyase deficiency) caused by a homozygous p.R96W mutation on exon 1 of the CYP17 gene, an unusual genotype in Brazilian patients with this form of CAH. The patient, raised as a normal female, sought medical care for lack of pubertal signs and primary amenorrhea at the age of 16 years. At evaluation, the presence of a 46,XY karyotype, hypertension and hypokalemia were observed. We emphasize the recognition of CYP17 deficiency in the differential diagnosis of cases of hypergonadotrophic hypogonadism and hypertension in young patients who need specific treatment for both situations.A hiperplasia adrenal congênita (HAC), em razão da deficiência de 17α-hidroxilase/17,20-liase, é uma doença autossômica recessiva rara e a segunda causa mais comum de HAC no Brasil. Descrevemos o caso de um paciente brasileiro portador da deficiência 17α-hidroxilase/17,20- liase (CYP17) em homozigose para a mutação p.R96W no éxon 1 do gene da CYP17A1, uma mutação incomum entre os casos brasileiros descritos com essa forma de HAC. Esse paciente, criado como um indivíduo normal do sexo feminino, procurou atendimento por ausência de sinais puberais e amenorreia primária aos 16 anos de idade. Durante a avaliação, constataram-se um cariótipo 46,XY e a presença de hipertensão e hipocalemia. Enfatizamos o reconhecimento da deficiência da CYP17 dentre os possíveis diagnósticos em um paciente jovem com hipogonadismo hipergonadotrófico e hipertensão, os quais necessitam de tratamento particularizado para ambas as situações.Universidade Federal do Rio Grande do Sul Hospital de Clínicas de Porto AlegreUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Department of MedicineUniversity of Texas Southwestern Medical Center Department of Internal MedicineUNIFESP, EPM, Department of MedicineSciEL

    A trust model using edge nodes and cuckoo filter for securing vanet under nlos conditions

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    Trust, as a key element of security, has a vital role in securing vehicular ad-hoc networks (VANETs). Malicious and selfish nodes by generating inaccurate information, have undesirable impacts on the trustworthiness of the VANET environment. Obstacles also have a negative impact on data trustworthiness by restricting direct communication between nodes. In this study, a trust model based on plausibility, experience, and type of vehicle is presented to cope with inaccurate, incomplete and uncertainty data under both line of sight (LoS) and none-line of sight (NLoS) conditions. In addition, a model using the k-nearest neighbor (kNN) classification algorithm based on feature similarity and symmetry is developed to detect the NLoS condition. Radio signal strength indicator (RSSI), packet reception rate (PDR) and the distance between two vehicle nodes are the features used in the proposed kNN algorithm. Moreover, due to the big data generated in VANET, secure communication between vehicle and edge node is designed using the Cuckoo filter. All obtained results are validated through well-known evaluation measures such as precision, recall, overall accuracy, and communication overhead. The results indicate that the proposed trust model has a better performance as compared to the attack-resistant trust management (ART) scheme and weighted voting (WV) approach. Additionally, the proposed trust model outperforms both ART and WV approaches under diffierent patterns of attack such as a simple attack, opinion tampering attack, and cunning attack. Monte-Carlo simulation results also prove validity of the proposed trust model

    The effects of vitamin D supplementation on interictal serum levels of calcitonin gene-related peptide (CGRP) in episodic migraine patients: Post hoc analysis of a randomized double-blind placebo-controlled trial

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    Background: Emerging evidence showed promising effects of vitamin D on headaches characteristics. Thus, it seems there is still a need for more researches to clarify the mechanisms by which this vitamin exerts anti-migraine effects. Methods: The present study was conducted as a 16-week randomized double-blind placebo-controlled trial on 80 episodic migraine patients allocated in 2 parallel groups each consisted of 40 patients who received vitamin D 2000 IU/d or placebo. At baseline and after the intervention completion, headache diaries and migraine disability assessment questionnaire (MIDAS) were used to assess migraine related variables in patients. Also, interictal serum concentration of calcitonin gene-related peptide (CGRP) (as the dominant mediator of migraine pain pathogenesis) was evaluated using ELISA method. Results: The mean (SD) of age in the vitamin D and placebo groups was 37 (8) and 38 (12) years, respectively. ANCOVA test adjusted for baseline values, and confounders showed vitamin D supplementation resulted in a significant improvement in MIDAS score after 12 weeks in the intervention group (21.49 (16.22-26.77)) compared to placebo (31.16 (25.51-36.82) P value: 0.016). Moreover, after controlling for baseline levels, and other variables using ANCOVA, CGRP level was appeared to be significantly lower following vitamin D supplementation (153.26 (133.03-173.49) ng/L) than the patients in the placebo arm (188.35 (167.15-209.54) ng/L) (P value = 0.022). Conclusion: According to the current findings, vitamin D supplementation in episodic migraineurs, particularly in those with migraine with aura, may potentially improve migraine headache characteristics and disability probably through attenuating CGRP levels. Therefore, these results could provide a new insight into anti-nociceptive effects of vitamin D; however, more studies are required to confirm our findings. Trial registration: The trial is registered in the Iranian registry of clinical trials (IRCT) at 11 July 2018, with IRCT code: IRCT20151128025267N6. © 2020 The Author(s)

    Diabetes mellitus and oral lichen planus: A systematic review and meta-analysis

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    Objective: To undertake a meta-analysis of the association of Oral Lichen Planus (OLP) with diabetes, two diseases with an important impact on public health and the economy, but the evidence of which about their association is inconsistent. Methods: Relevant studies were localized by searching MEDLINE, EMBASE, Conference Proceedings, and other databases from inception to October 2020, without restrictions. The reference lists of included studies and of related reviews were also inspected. Global pooled odds ratios were calculated, and predefined subgroup analyses were performed. The heterogeneity between studies and publication bias was assessed and sensitivity analysis was carried out. Results: Thirty-two studies were included in the meta-analysis. Pooled ORs showed a moderate association between diabetes and OLP [OR: 1.87 (95%CI: 1.57, 2.34)]. The association is limited to studies carried out on adults only [OR: 2.12 (95%CI: 1.75, 2.57)] and is observed in all study designs. Globally, the heterogeneity was low to moderate. Studies carried out in European populations show a stronger association of diabetes and OLP than Asiatic studies [OR: 2.49 (95%CI: 1.87, 3.32) and 1.60 (95%CI: 1.25, 2.03), respectively]. Conclusions: Diabetes and OLP are moderately associated. Systematic diagnosis of diabetes in OLP patients could prove usefulS

    Non-Standard Errors

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    In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants
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