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Abstract Serious leakage occurred in a jacketed poly-condensation autoclave which is subjected with temperature and pressure cycles. By using finite element method, the simulation and calculation was carried out and the result was analyzed. It was found that there were shortcomings in original design. Therefore, the improvement was carried out. For improved equipment, under various working conditions with cyclic mechanical loads, thermal-structural analysis was, then, performed. The results were passed in checking for stresses and fatigue capacity. In this way, the leakage problem has been solved. The studied result presented in this paper provides the basis for optimum design of jacketed vessels. Highlights • Jacketed containers are common reaction equipment in the petroleum, chemical, pharmaceutical and food industries. Jacketed container with complex structure suffer from enormous inevitable thermal and structural stresses. How to properly handle the stress of the jacketed container is very important. • Containers with complex structures and loads often experience leak failures. This paper provides a leak failure analysis method based on strength analysis and fatigue analysis. • Stress concentration usually occurs at the junction of the jacketed container. This paper uses a 45°flanging structure to solve this stress concentration phenomenon. • This paper contributes to the failure analysis of a poly-condensation autoclave, which indicates the improper selection of the jacket material and defect structure of the support pipe for the thermal well. [ABSTRACT FROM AUTHOR]

Objective(s): The aim of this study is to explore the potential neuroprotective effects of Ginkgolide B (GB), a main terpene lactone and active component in Ginkgo biloba, in hypoxia-induced neuronal damage, and to further investigate its possible mechanisms. Materials and Methods: 54 Sprague-Dawley rats were randomly divided into three groups: the untreated control group (n=18); the hypoxia group (n=18; exposed to 6000 m simulated plateau altitude for six days); and the GB group (n=18; intragastric administration of 12 mg/kg GB three days prior to rapid adaption to 6000 m and on the first two days of hypoxia). After hypoxia exposure for six days, we dissected out the brain hippocampi and performed hematoxylin and eosin staining, Nissl staining, and TUNEL staining. Homogenates of the hippocampi were used to test the oxidative stress indices including malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and catalase. Bax and caspase-3 expression in the hippocampal tissue was measured using qRT-PCR. Results: Treatment with GB before exposure to hypoxia could protect neural cells and increase the number of Nissl bodies. TUNEL and qRT-PCR results demonstrated that GB treatment could decrease apoptotic cells in different areas of the hippocampus. Antioxidant defense systems such as SOD, GSH, and catalase were decreased (P<0.05), and the concentration of MDA was reduced significantly in the hippocampi of rats of the GB group (P<0.05). Conclusion: GB could alleviate hypoxia-induced neuronal damage in rat hippocampus by inhibiting oxidative stress and apoptosis. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is involved in neuronal modifications, and overproduction of NO contributes to memory deficits after acute hypobaric hypoxia-reoxygenation. This study investigated the ability of the iNOS inhibitor 1400 W to counteract spatial memory deficits following acute hypobaric hypoxia-reoxygenation, and to affect expression of NOS, NO, 3-NT and MDA production, and apoptosis in rat cerebral cortex. We also used primary rat microglia to investigate the effect of 1400 W on expression of NOS, NO, 3-NT and MDA production, and apoptosis. Acute hypobaric hypoxia-reoxygenation impaired spatial memory, and was accompanied by activated microglia, increased iNOS expression, NO, 3-NT and MDA production, and neuronal cell apoptosis in rat cerebral cortex one day post-reoxygenation. 1400 W treatment inhibited iNOS expression without affecting nNOS or eNOS. 1400 W also reduced NO, 3-NT and MDA production, and prevented neuronal cell apoptosis in cerebral cortex, in addition to reversing spatial memory impairment after acute hypobaric hypoxia-reoxygenation. Hypoxia-reoxygenation activated primary microglia, and increased iNOS and nNOS expression, NO, 3-NT, and MDA production, and apoptosis. Treatment with 1400 W inhibited iNOS expression without affecting nNOS, reduced NO, 3-NT and MDA production, and prevented apoptosis in primary microglia. Based on the above findings, we concluded that the highly selective iNOS inhibitor 1400 W inhibited iNOS induction in microglial cells, and reduced generation of NO, thereby mitigating oxidative stress and neuronal cell apoptosis in the rat cerebral cortex, and improving the spatial memory dysfunction caused by acute hypobaric hypoxia-reoxygenation. [ABSTRACT FROM AUTHOR]

The typical methods for the wire fault location are the time-domain reflectometry (TDR) and frequency-domain reflectometry (FDR). In TDR, attenuation and dispersion of the reflected signal limit the reachable accuracy for wire faults location. Because time of flight is evaluated, the wire faults with small impedance changes are difficult to locate. The FDR method has better accuracy than the TDR method, because power signals are used as incident signals and Fourier transform is applied to locate wire faults. However, it is difficult to identify the types of wire faults. A new technique is proposed to detect and locate the wire fault using impedance spectroscopy (IS). IS is applied to measure the input impedance of the wiring system. The load impedance of the wire fault can be abstracted from the input impedance in order to identify the type of wire faults. The input impedance is a period function of the frequency and the period of this function is linearly proportional to the distance to the fault. The fast Fourier transform of the input impedance can give a single spike to locate the wire fault. This novel method enables the location of hard (open and short circuits) and soft (wire faults with small impedance changes) faults. The input impedance of the wire faults in the defined low-frequency range can be applied to identify the types of wire faults. The capacitance and inductance of the cable system can be applied to detect the wire fault if it is open or short circuit. The measurement deviation of the wire fault location in this paper is maximal 40 cm and is independent of the distance to wire faults. [ABSTRACT FROM PUBLISHER]

Abstract: Inflammatory responses are important to host immune reactions, but uncontrolled inflammatory mediators may aid in the pathogenesis of other inflammatory diseases. Geniposide, an iridoid glycoside found in the herb gardenia, is believed to have broad-spectrum anti-inflammatory effects in murine models but its mechanism of action is unclear. We investigated the action of this compound in murine macrophages stimulated by lipopolysaccharide (LPS), as the stimulation of macrophages by LPS is known to induce inflammatory reactions. We determined the effect of geniposide on LPS-induced production of the inflammatory mediators, nitric oxide (NO) and prostaglandin E2 (PGE2), the mRNA and protein expression of the NO and PGE2 synthases, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), respectively, and the mRNA and protein expression of the inflammatory cytokine, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Furthermore, nuclear factor (NF)-κB, mitogen-activated protein kinase (MAPK) and activator protein (AP)-1 activity were assayed. To understand the action of geniposide on the NF-κB and MAPK pathways, we studied the effect of NF-κB and MAPK inhibitors on the LPS-induced production of NO, PGE2 and TNF-α. Our findings clearly showed that geniposide mainly exerts its anti-inflammatory effects by inhibiting the LPS-induced NF-κB, MAPK and AP-1 signaling pathways in macrophages, which subsequently reduces overexpression of the inducible enzymes iNOS and COX-2 and suppresses the expression and release of the inflammatory factors, TNF-α, IL-6, NO and PGE2. Thus, geniposide shows promise as a therapeutic agent in inflammatory diseases. [Copyright &y& Elsevier]

Acute exposure to high altitudes can cause neurological dysfunction due to decreased oxygen availability to the brain. In this study, the protective effects of Huperzine A on cognitive deficits along with oxidative and apoptotic damage, due to acute hypobaric hypoxia, were investigated in male Sprague-Dawley rats. Rats were exposed to simulated hypobaric hypoxia at 6,000 m in a specially fabricated animal decompression chamber while receiving daily Huperzine A orally at the dose of 0.05 or 0.1 mg/kg body weight. After exposure to hypobaric hypoxia for 5 days, rats were trained in a Morris Water Maze for 5 consecutive days. Subsequent trials revealed Huperzine A supplementation at a dose of 0.1 mg/kg body weight restored spatial memory significantly, as evident from decreased escape latency and path length to reach the hidden platform, and the increase in number of times of crossing the former platform location and time spent in the former platform quadrant. In addition, after exposure to hypobaric hypoxia, animals were sacrificed and biomarkers of oxidative damage, such as reactive oxygen species, lipid peroxidation, lactate dehydrogenase activity, reduced glutathione, oxidized glutathione and superoxide dismutase were studied in the hippocampus. Expression levels of pro-apoptotic proteins (Bax, caspase-3) and anti-apoptotic protein (Bcl-2) of hippocampal tissues were evaluated by Western blotting. There was a significant increase in oxidative stress along with increased expression of apoptotic proteins in hypoxia exposed rats, which was significantly improved by oral Huperzine A at 0.1 mg/kg body weight. These results suggest that supplementation with Huperzine A improves cognitive deficits, reduces oxidative stress and inhibits the apoptotic cascade induced by acute hypobaric hypoxia. [ABSTRACT FROM AUTHOR]

Background: Although assays for detecting Yersinia pestis using TaqMan probe-based real-time PCR have been developed for years, little is reported on room-temperature-stable PCR reagents, which will be invaluable for field epidemic surveillance, immediate response to public health emergencies, counter-bioterrorism investigation, etc. In this work, a set of real-time PCR reagents for rapid detection of Y. pestis was developed with extraordinary stability at 37°C. Methods/Principal Findings: TaqMan-based real-time PCR assays were developed using the primers and probes targeting the 3a sequence in the chromosome and the F1 antigen gene caf1 in the plasmid pMT1of Y. pestis, respectively. Then, carbohydrate mixtures were added to the PCR reagents, which were later vacuum-dried for stability evaluation. The vacuum-dried reagents were stable at 37°C for at least 49 days for a lower concentration of template DNA (10 copies/µl), and up to 79 days for higher concentrations (≥102 copies/µl). The reagents were used subsequently to detect soil samples spiked with Y. pestis vaccine strain EV76, and 5×104 CFU per gram of soil could be detected by both 3a- and caf1-based PCR reagents. In addition, a simple and efficient method for soil sample processing is presented here. Conclusions/Significance: The vacuum-dried reagents for real-time PCR maintain accuracy and reproducibility for at least 49 days at 37°C, indicating that they can be easily transported at room temperature for field application if the machine for performing real-time PCR is available. This dry reagent is of great significance for routine plague surveillance. Author Summary: Plague, caused by Yersinia pestis, is one of the oldest and most dangerous diseases in human history, and has claimed millions of lives in the three major historical pandemics. Although panic caused by the Black Death is fading, the threat of the reemergence of plague pandemics still exists, with the additional potential of misuse in biowarfare or bioterrorism. Rapid on-site detection and identification of the pathogen is of paramount significance for timely implementation of effective countermeasures. TaqMan probe-based real-time PCR assays can give quick and accurate identification; however, the need for cold delivery and storage prevents its potential on-site application. The objective of this study was to develop a stable PCR system for easy delivery and storage under room temperature, which is vital for conventional plague surveillance and for preparedness in public health emergencies. We present a solution to this particular issue, hoping that it is helpful to future applications. [ABSTRACT FROM AUTHOR]