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To substitute synthetic fibers, which are non-biodegradable and environmentally unfriendly, studies have been carried out to exploit vegetable fibers. Within this concept, this work investigates Sida rhombifolia as a case study. Previous studies showed that the fibers could be extracted only by cold water retting, but this study seeks to show that the boiling water extraction technique can also be used. The objective of this study is to characterize Sida rhombifolia fibers from the Center region of Cameroon, extracted with cold and boiling water, and compare their physico-chemical and mechanical properties with those of other vegetable fibers. The standard tests for the different characterizations have been respected. This study showed that the fibers extracted with cold water retting contained 70.16% cellulose, 16.70% hemicellulose, 10.86% lignin, and 1.47% pectin, while the fibers extracted by boiling water technique contained 68.71% cellulose, 17.48% hemicellulose, 11.26% lignin, and 2.01% pectin. Finally, extraction of fibers from the cold water retting technique gave 38.83% extraction yield, 1.33 g.cm−3 density, 11.23 tex linear mass, 11.73% water content, 118.53% rate of water absorption, and 21.45% humidity at a relative humidity of 75%. While fibers extracted by the boiling water technique had 33.74% extraction yield, 1.35 g.cm−3 density, 13.57 tex linear mass, 13.28% water content, 225.12% rate of water absorption, and 22.06% humidity at a relative humidity of 75%, statistical analysis by Student’s t-test showed a significant difference in the mechanical properties of the fibers depending on the extraction method. Sida rhombifolia fibers can be used in textiles and composites and can be extracted by the boiling water technique.

Objectives The aim of this study is a descriptive presentation of cases of acute watery diarrhoea (AWD) that were presented to Aleppo University Hospital (AUH) during the recent cholera outbreak in Syria.Design Prospective, observational, cohort study.Setting and participants A total of 1061 patients with AWD were admitted to AUH during the timeframe of 20 September 2022 to 20 October 2022. The data collection was done through a structured questionnaire. This includes comprehensive clinical observation, laboratory analyses, therapeutic interventions and holistic case evaluations.Results The analysis has revealed notable insights: a predominant proportion of patients (58.6%) were residents from urban areas and 40.3% were residents from rural areas. Intriguingly, a diverse range of potential infection sources emerged from patient data within our hospital, including uncontrolled well water, vegetables and faecal-oral transmission through contaminated street/fast food. At discharge, most patients were in good health (79.7%), followed by moderate health (17.6%) and poor health (2.3%), with a minimal percentage dying before discharge (0.4%). The most common complications reported at admission and during hospitalisation included electrolyte imbalance (28.2%), followed by severe dehydration (16.3%). In the follow-up period, the majority of patients exhibited good health (81.0%). Older patients (>60 years) had poorer outcomes, with 8.4% having poor health and 4.2% death rate.Conclusions The study found results consistent with previous AWD outbreaks in developing countries like Yemen, Nigeria and Lebanon. Preventative measures like improving water sanitation and hygiene practices are essential to prevent future outbreaks and ease the strain on healthcare systems. Therefore, future studies must investigate the risk factors that increase the spread and the severity of the disease and investigate the best management method.

In this work, we seek to investigate the dynamics of bright soliton in a chain of coupled pendulum pairs. After deriving the linear dispersion relation from the equation of the model, we find that among the obtained modes, the fast mode is the one on which we are going to be focused. Since the discrete simultaneous equation describing the dynamics of the model has not been extensively studied in the literature, we assume that the two lines of the model are proportional to each other. We use the rotating wave approximation method to derive a NLS equation governing the propagation of waves in the network. Depending on the choice of wave number, we deduce that the system supports bright and hole-soliton solutions. We use the obtained bright soliton as the initial condition for numerical computation, which demonstrates the significant role of the transverse coupling parameter in the system. That is, it affects the behavior of the forward-bright soliton generated in the system. The lattice allows gain and loss phenomena during the propagation of the waves. [ABSTRACT FROM AUTHOR]

Aims: A crossover double-blind, randomized study was designed to explore the efficacy of 2% mepivacaine with 1:100,000 adrenaline buccal infiltration and 4% articaine with 1:100,000 adrenaline buccal infiltration following 2% mepivacaine with 1:100,000 adrenaline inferior alveolar nerve block (IANB) for testing pulp anesthesia of mandibular first molar teeth in adult volunteers. Materials and Methods: A total of 23 healthy adult volunteers received two regimens with at least 1-week apart; one with 4% articaine buccal infiltration and 2% mepivacaine IANB (articaine regimen) and another with 2% mepivacaine buccal infiltration supplemented to 2% mepivacaine IANB (mepivacaine regimen). Pulp testing of first molar tooth was electronically measured twice at baseline, then at intervals of 2 min for the first 10 min, then every 5 min until 45 min postinjection. Anesthetic success was considered when two consecutive maximal stimulation on pulp testing readings without sensation were obtained within 10 min and continuously sustained for 45 min postinjection. Results: In total, the number of no sensations to maximum pulp testing for first molar teeth were significantly higher after articaine regimen than mepivacaine during 45 min postinjection (267 vs. 250 episodes, respectively, P < 0.001), however, both articaine and mepivacaine buccal infiltrations are equally effective in securing anesthetic success for first molar pulp anesthesia when supplemented to mepivacaine IANB injections (P > 0.05). Interestingly, volunteers in the articaine regimen provided faster onset and longer duration (means 2.78 min, 42.22 min, respectively) than mepivacaine regimen (means 4.26 min, 40.74 min, respectively) for first molar pulp anesthesia (P < 0.001). Conclusions: Supplementary mepivacaine and articaine buccal infiltrations produced similar successful first molar pulp anesthesia following mepivacaine IANB injections in volunteers. Articaine buccal infiltration produced faster onset and longer duration than mepivacaine buccal infiltration following mepivacaine IANB injections.

Nitric oxide (*NO) generation from conversion of L-arginine to citrulline by nitric oxide synthase isoforms plays a critical role in vascular homeostasis. Loss of *NO is linked to vascular pathophysiology and is decreased in chronically inflamed gut blood vessels in inflammatory bowel disease (IBD; Crohn's disease and ulcerative colitis). Mechanisms underlying decreased .NO production in IBD gut microvessels are not fully characterized. Loss of *NO generation may result from increased arginase (AR) activity, which enzymatically competes with nitric oxide synthase for the common substrate L-arginine. We characterized AR expression in IBD microvessels and endothelial cells and its contribution to decreased *NO production. AR expression was assessed in resected gut tissues and human intestinal microvascular endothelial cells (HIMEC). AR expression significantly increased in both ulcerative colitis and Crohn's disease microvessels and submucosal tissues compared with normal. TNF-[alpha]/lipopolysaccharide increased AR activity, mRNA and protein expression in HIMEC in a time-dependent fashion. RhoA/ ROCK pathway, a negative regulator of *NO generation in endothelial cells, was examined. The RhoA inhibitor C3 exoenzyme and the ROCK inhibitor Y-27632 both attenuated TNF-[alpha]/lipopolysaccharide-induced MAPK activation and blocked AR expression in HIMEC. A significantly higher AR activity and increased RhoA activity were observed in IBD submucosal tissues surrounding microvessels compared with normal control gut tissue. Functionally, inhibition of AR activity decreased leukocyte binding to HIMEC in an adhesion assay. Loss of *NO production in IBD microvessels is linked to enhanced levels of AR in intestinal endothelial cells exposed to chronic inflammation in vivo. endothelium; microvasculature; nitric oxide synthase doi: 10.1152/ajpgi.00499.2006.

The heat shock response maintains cellular homeostasis following sublethal injury. Heat shock proteins (Hsps) are induced by thermal, oxyradical, and inflammatory stress, and they chaperone denatured intracellular proteins. Hsps also chaperone signal transduction proteins, modulating signaling cascades during repeated stress. Gastroesophageal reflux disease (GERD) affects 7% of the US population, and it is linked to prolonged esophageal acid exposure. GERD is characterized by enhanced and selective leukocyte recruitment from esophageal microvasculature, implying activation of microvascular endothelium. We investigated whether phosphatidylinositol 3-kinase (PI3K)/Akt and MAPK regulate Hsp induction in primary cultures of human esophageal microvascular endothelial cells (HEMEC) in response to acid exposure (pH 4.5). Inhibitors of signaling pathways were used to define the contribution of PI3K/Akt and MAPKs in the heat shock response and following acid exposure. Acid significantly enhanced phosphorylation of Akt and MAPKs in HEMEC as well as inducing Hsp27 and Hsp70. The PI3K inhibitor LY-294002, and Akt small interfering RNA inhibited Akt activation and Hsp70 expression in HEMEC. The p38 MAPK inhibitor (SB-203580) and p38 MAPK siRNA blocked Hsp27 and Hsp70 mRNA induction, suggesting a role for MAPKs in the HEMEC heat shock response. Thus acidic pH exposure protects HEMEC through induction of Hsps and activation of MAPK and PI3 kinase pathway. Acidic exposure increased HEMEC expression of VCAM-1 protein, but not ICAM-1, which may contribute to selective leukocyte (i.e., eosinophil) recruitment in esophagitis. Activation of esophageal endothelial cells exposed to acidic refluxate may contribute to GERD in the setting of a disturbed mucosal squamous epithelial barrier (i.e., erosive esophagitis, peptic ulceration). esophagus; esophagitis; gastroesophageal reflux disease; microvasculature; phosphatidylinositol 3-kinase/Akt; VCAM-1