314 research outputs found

    NDM-534: SENSITIVITY OF WIND INDUCED DYNAMIC RESPONSE OF A TRANSMISSION LINE TO VARIATIONS IN WIND SPEED

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    This paper studies the dynamic behavior of a multi-span transmission line system under synoptic wind considering various speeds to determine the range of wind speeds in which the system experiences resonance. A finite element numerical model was developed for the purpose of this study. This model is employed to assess the dynamic behavior of a self-supported lattice tower line under various wind speeds. Dynamic Amplification Factor (DAF), defined as the ratio between the peak total response to the peak quasi-static response, is evaluated. It is found that conductors’ responses exhibit large DAF compared to the towers especially at low wind speeds (v ≤ 25 m/s). This results from the low natural frequency of the conductors (0.19 Hz) which is close to the wind load frequency while the natural frequency of the tower is equal to 2.36 Hz. In addition, the conductors’ aerodynamic damping decreases with the decrease of wind speed which leads to higher dynamic effect while the tower’s aerodynamic damping plays a minor role. The results of the dynamic analysis conducted in this study are also used to compare the gust response factors (GFT), defined as the ratio between peak total response to the mean response, to those obtained from the ASCE code (GFT-ASCE). It has been noticed that the gust response factors obtained from the ASCE code lead to conservative peak responses for both towers and conductors of the chosen line

    Elimination of high-refined-sugar diet as treatment strategy for autistic features induced in a rodent model

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    Purpose: To investigate the potency of ampicillin in altering gut flora in the presence of a high-sucrose diet in rat pups, and to determine its effect on selected neurotransmitters and a cytokine as markers of the persistent autistic features repeatedly induced in orally administered propionic acid rat pups..Methods: Twenty-eight young male Wistar albino rats were divided into four equal groups. The first group served as a control. The second group received an oral neurotoxic dose of propionic acid (PPA, 250 mg/kg body weight/day) for 3 days. The third group was treated with ampicillin (50 mg/kg for 3 weeks) with a standard diet. The fourth group was given the same dose of ampicillin with a high-sucrose diet for 10 weeks.Results: The results showed a significant (p < 0.001) decrease in the investigated neurotransmitters in PPA- and ampicillin-treated rat pups (norepinephrine by 32.49 and 14.58 %, dopamine by 31.45 and 20.22 %, serotonin by 35.99 and 29.09 %), as well as a remarkable increase (p < 0.001) in the proinflammatory cytokine, IL-6 (30.07and 6.07 %). The high-sucrose diet also significantly (p < 0.001) enhanced the neurotoxic effect of ampicillin.Conclusion: The observed dietary modulation of the gut microbiota, coupled with the subsequent modulation of brain neurochemistry and inflammation, demonstrates the considerable potential of dietary intervention through the elimination of highly refined sugar as a treatment strategy to prevent and treat autism.Keywords: Neurotoxicity, Ampicillin, Propionic acid, Neurotransmitters, Cytokines, High-sucrose die

    Exploiting the Synergy Between Gossiping and Structured Overlays

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    In this position paper we argue for exploiting the synergy between gossip-based algorithms and structured overlay networks (SON). These two strands of research have both aimed at building fault-tolerant, dynamic, self-managing, and large-scale distributed systems. Despite the common goals, the two areas have, however, been relatively isolated. We focus on three problem domains where there is an untapped potential of using gossiping combined with SONs. We argue for applying gossip-based membership for ring-based SONs---such as Chord and Bamboo---to make them handle partition mergers and loopy networks. We argue that small world SONs---such as Accordion and Mercury---are specifically well-suited for gossip-based membership management. The benefits would be better graph-theoretic properties. Finally, we argue that gossip-based algorithms could use the overlay constructed by SONs. For example, many unreliable broadcast algorithms for SONs could be augmented with anti-entropy protocols. Similarly, gossip-based aggregation could be used in SONs for network size estimation and load-balancing purposes

    Bioactivities of Traditional Medicinal Plants in Alexandria

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    In traditional folklore, medicinal herbs play a vital role in the prevention and treatment of microbial diseases. In the present study, the phenolic profiles of the medicinal plants Asparagus aethiopicus L., Citrullus colocynthis L., Senna alexandrina L., Kalanchoe delagoensis L., Gasteria pillansii L., Cymbopogon citratus, Brassica juncea, and Curcuma longa L. were determined by high-performance liquid chromatography with a diode-array detector method. The results revealed rich sources of important compounds such as robinin in the fruits and leaves of A. aethiopicus; caffeic acid in the tubers of A. aethiopicus and quercitrin in the leaves of G. pillansii. Further, relatively high antioxidant, antibacterial, and antifungal activities were observed in C. colocynthis fruit coat, S. alexandrina pods, and A. aethiopicus leaves, respectively. The relatively higher the bioactivities of plants extracts associated with the phenols in these plants, in particular, the more abundant the phenols. Therefore, it was concluded that the fruit coat of C. colocynthis, pods of S. alexandrina, and leaves of A. aethiopicus might be excellent sources of natural products. These plant extracts also have a wide spectrum of antimicrobial activities that could be used in the pharmaceutical industries and to control diseases

    The protective effect of Moringa oleifera plant extract against glutamate-induced DNA damage and reduced cell viability in a primary retinal ganglion cell line

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    Background Glutamate excitotoxicity can cause DNA damage and is linked to many retinal and neurological disorders. In mammals, the visual signal from the eyes to the brain is conducted only by retinal ganglion cells (RGCs), which can be damaged by overstimulation of glutamate receptors. Methodology We examined the protective effects of Moringa oleifera seed extract against glutamate-induced DNA damage in RGCs. RGCs cells were treated with 5, 10, 50, or 100 µg/ml of M. oleifera seed extract and glutamate separately and then assessed for DNA damage using the comet assay. We also evaluated the viability of the RGCs after both treatments using the MTT test. Additionally, RGCs were pretreated with M. oleifera seed extract (50 or 100 µg/ml) for 2 h before glutamate treatment (100 µg/ml) to determine the potential protective effects of M. oleifera. We performed a phytochemical analysis of the M. oleifera seed extract using standard reactions. Results The M. oleifera seed extract was found to be rich in many phytochemicals. We observed a significant dose-dependent elevation in all comet assay variables in glutamate-treated RGCs, whereas M. oleifera seed extract treatments did not show any significant change in DNA integrity. Conclusion M. oleifera seed extract demonstrates neuroprotective effects, which suggests it may help to prevent the development of many neurodegenerative disorders

    Allelic Discrimination of Vitamin D Receptor Polymorphisms and Risk of Type 2 Diabetes Mellitus: A Case-Controlled Study

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    (1) Background: Type 2 diabetes mellitus (T2DM) is one of the rapidly growing healthcare problems, and several vitamin D receptor (VDR) polymorphisms seem to modulate the risk of T2DM. Our research was designed to investigate the allelic discrimination of VDR polymorphisms and T2DM occurrence risk. (2) Methods: This case-control research included 156 patients with T2DM and 145 healthy control subjects. Most of the study population were males 56.6% vs. 62.8% in the case and control groups, respectively. Genotyping for VDR single nucleotide polymorphisms (SNPs), rs228570 (Fok1), rs7975232 (Apa1), and rs1544410 (Bsm1) was compared between both groups. (3) Results: There was a negative link between vitamin D levels and insulin sensitivity. A significant difference was noted in the allelic discrimination of VDR polymorphism rs228570 and rs1544410 between the study groups (p \u3c 0.001). No difference was observed in the allelic discrimination of VDR polymorphism rs7975232 between the groups (p = 0.063). Moreover, T2DM patients had significantly higher levels of fasting blood sugar (FBS), glycated hemoglobin HbA1c, 2-h post-prandial blood sugar (PP), serum glutamic oxaloacetic transaminase (SGOT), serum glutamic-pyruvic transaminase (SGPT), total cholesterol, and triglycerides (p \u3c 0.001), while High-Density Lipoprotein (HDL) Cholesterol (HDL-C) was significantly decreased (p = 0.006). (4) Conclusions: VDR polymorphisms had a positive association with T2DM risk among the Egyptian population. Further large-scale research using deep sequencing of samples is strongly urged to investigate different vitamin D gene variants and interactions, as well as the influence of vitamin D on T2DM

    Mechanism of nitrogen metabolism-related parameters and enzyme activities in the pathophysiology of autism

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    <p>Abstract</p> <p>Background</p> <p>There is evidence that impaired metabolism play an important role in the etiology of many neuropsychiatric disorders. Although this has not been investigated to date, several recent studies proposed that nitrogen metabolism-related parameters may have a pathophysiological role in autism.</p> <p>Methods</p> <p>The study enrolled 20 Saudi boys with autism aged 4 to 12 years and 20 healthy controls matched for age and gender. Levels of creatine, urea, ammonia, gamma-aminobutyric acid (GABA), glutamate:glutamine (Glu:Gln) ratio, and enzymatic activities of glutamate dehydrogenase, 5'-nucleotidase, and adenosine deaminase (ADA) were determined in plasma samples from both groups.</p> <p>Results</p> <p>We found a significant elevation of creatine, 5'-nucleotidase, GABA, and glutamic acid and a significant decrease in the enzymatic activity of ADA and glutamine level in patients with autism compared with healthy controls. The most significant variation between the two groups was found in the Glu:Gln ratio.</p> <p>Conclusion</p> <p>A raised Glu:Gln ratio together with positive correlations in creatine, GABA, and 5'-nucleotidase levels could contribute to the pathophysiology of autism, and might be useful diagnostic markers. The mechanism through which these parameters might be related to autism is discussed in detail.</p

    Septic rupture of the ascending aorta after aortocoronary bypass surgery

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    We describe an exceptional case of non-fatal septic rupture of the ascending aorta in a patient with sternal dehiscence, deep sternal wound infection (DSWI) and pleural empyema after aortocoronary bypass surgery. Routine follow-up computed tomography (CT) detected a mediastinal pseudoaneurysm originating from the ascending aorta. Thereby, massive and irregular sternal bone defects and contrast-enhancing mediastinal soft tissue suggest osteomyelitis and highly-active and aggressive DSWI as initial triggers. Urgent thoracotomy 1 day later included ascending aorta reconstruction, total sternum resection and broad wound debridement. Follow-up CT 1 year later showed a regular postoperative result in a fully recovered patient

    Why do consumers trust online travel websites? Drivers and outcomes of consumer trust toward online travel websites

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    Egypt is currently one of the leading nations especially in the Middle East region with a well-established e-commerce environment and advanced IT infrastructure, but rapid growth of e-commerce will soon occur in other nations with similar consumption patterns. This study tests a model of antecedents (consumer experience, propensity to trust, reputation, perceived website size, ease of use, perceived usefulness, and website quality) and consequences of consumers’ trust toward online travel websites. Trust is expected to predict consumer attitude, perceived risk, and intention to purchase travel online. Data of 1,431 users of online travel websites were selected from the Supreme Council of Universities Database–Egypt (SCU) and analyzed through structural equation modeling. The findings show that all the aforementioned factors with the exception of consumer experience influence consumer trust toward online travel websites. Trust influences consumers’ attitude, perceived risk, and intention to purchase travel online

    Novel metabolic biomarkers related to sulfur-dependent detoxification pathways in autistic patients of Saudi Arabia

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    <p>Abstract</p> <p>Background</p> <p>Xenobiotics are neurotoxins that dramatically alter the health of the child. In addition, an inefficient detoxification system leads to oxidative stress, gut dysbiosis, and immune dysfunction. The consensus among physicians who treat autism with a biomedical approach is that those on the spectrum are burdened with oxidative stress and immune problems. In a trial to understand the role of detoxification in the etiology of autism, selected parameters related to sulfur-dependent detoxification mechanisms in plasma of autistic children from Saudi Arabia will be investigated compared to control subjects.</p> <p>Methods</p> <p>20 males autistic children aged 3-15 years and 20 age and gender matching healthy children as control group were included in this study. Levels of reduced glutathione (GSH), total (GSH+GSSG), glutathione status (GSH/GSSG), glutathione reductase (GR), glutathione- s-transferase (GST), thioredoxin (Trx), thioredoxin reductase (TrxR) and peroxidoxins (Prxs I and III) were determined.</p> <p>Results</p> <p>Reduced glutathione, total glutathione, GSH/GSSG and activity levels of GST were significantly lower, GR shows non-significant differences, while, Trx, TrxR and both Prx I and III recorded a remarkably higher values in autistics compared to control subjects.</p> <p>Conclusion</p> <p>The impaired glutathione status together with the elevated Trx and TrxR and the remarkable over expression of both Prx I and Prx III, could be used as diagnostic biomarkers of autism.</p
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