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To investigate the genotype and clinical characteristics of carbapenem-resistant Enterobacteriaceae (CRE) strains in southwest China and provide information on the treatment stopping the spread of the infection. The clinical information of CRE isolates was collected from 19 hospitals in 12 cities across Sichuan Province, China, between June 2018 and April 2019. The isolates were detected by DNA sequencing of genes encoding carbapenem enzymes and multilocus sequence types (MLSTs). A total of 166 nonrepetitive CRE isolates were isolated during the study period from sputum, blood, urine, and other samples. Klebsiella pneumoniae carbapenemase (KPC) was dominant in Klebsiella pneumoniae (53.9%), followed by New Delhi metallo-β-lactamase (NDM) (42.1%). A total of 43 STs were detected. The most common ST of K. pneumoniae was ST11, and that of Escherichia coli was ST410. Pairwise single nucleotide polymorphism (SNP) distances and the likelihood of local transmission by epidemiology were plotted for each species. About 65% of these pairs had ≤ 20 pairwise SNPs. A large number of CRE strains carried carbapenemase. Although NDM-ST12 K. pneumoniae should not be disregarded, KPC-ST11is the predominant strain. Thus, the possibility of transmission between E. coli and K. pneumoniae could not be ignored. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae carbapenemase (KPC)-producing K.pneumoniae has represented a serious health problem in worldwide. The resistance to ceftazidime-avibactam (CAZ-AVI) began to emerge since its approval in 2015. We aim to explore the resistance mechanism of CAZ-AVI. Methods: Phenotypic test and whole-genome sequencing (WGS) analysis were performed in KP-HX0917 and KP-HX1016 Klebsiella pneumoniae isolates, collected from the same patient following treatment with CAZ-AVI. Results: We report a case of emergence of CAZ-AVI resistance in ST 11 KPC-2-producing K. pneumoniae (KP-HX1016) during 14 days of exposure with CZA-AVI. Molecular analysis highlighted the A533C mutation in the blaKPC-2 gene, resulting a D179A substitution in protein sequence, which restored the hydrolysis ability of imipenem and meropenem, but not for ertapenem, and the result of phenotypic test was negative. However, KP-HX0917 produced serine-carbapenemase by phenotypic detection and lost its capacity of hydrolyzing carbapenems. Conclusion: The emergence of CAZ-AVI resistance should arouse our attention, the susceptibility testing should be followed by a combination of phenotypic and molecular methods, to make sure that no potential carbapenemase-producing bacteria are missed. [ABSTRACT FROM AUTHOR]

• No single laboratory method could independently diagnose tuberculous meningitis. • Polymerase-chain-reaction is highly sensitive and specific for the diagnosis of tuberculous meningitis. • Metagenomic next-generation sequencing does not offer much strength in diagnosing tuberculous meningitis. The aim of this study was to comprehensively evaluate metagenomic next-generation sequencing (mNGS), Acid-fast bacillus stain (AFB), MGIT960 culture, polymerase-chain-reaction (PCR), and Xpert MTB/RIF in the diagnosis of tuberculous meningitis (TBM). A cohort of 280 patients who presented with suspected TBM (ie, headache or altered mental status with clinical signs of meningism) were analyzed. The sensitivities of the 5 assays for the diagnosis of TBM ranged from 10.0% to 70.0%. The AFB had the lowest sensitivity of 10.0% (0.5-45.9), while mNGS and PCR had the highest sensitivity, both at 70.0% (35.4-91.9). mNGS demonstrated a distinct advantage in identifying a wider array of pathogens, including viruses, in CSF samples. PCR was a cost-effective option with excellent sensitivity and specificity. However, no single method was statistically significantly better than any other in the diagnosis of TBM. New diagnostic techniques are urgently needed for the independent, rapid and accurate detection of Mycobacterium tuberculosis to guide the diagnosis of TBM. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Starches were isolated from five coarse grains. • The starches showed significantly different granule morphology and sizes. • The starches exhibited different structural properties and crystalline structure. • The starches exhibited different thermal and pasting properties. Abstract Starch, one of the most important components of coarse grains, has received widespread attention because of its prominent potential health benefits. In the present study, we isolated starches from the grains of sorghum, tartary buckwheat, common buckwheat, mungbean, and pea and studied their structural and physicochemical properties. These five starches all showed the distinctive "Maltese cross" effect (birefringence) but significantly differed in morphology, size, and complexity of granules. Sorghum starch exhibited the lowest amylose content and highest weight-average molar mass. Mungbean contained more short amylopectin [degree of polymerization (DP) 6–12 = 23.4%]. Pea starch exhibited the highest amylose content, highest amylopectin average chain length, and lowest weight-average molar mass. The starches of sorghum, tartary buckwheat, and common buckwheat showed A-type crystallinity, whereas those of mungbean and pea showed C-type crystallinity. Our results provide useful information for the application of coarse grain starches in diverse industries. [ABSTRACT FROM AUTHOR]

Abstract Nitrogen is an essential nutrient for Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) because this substance affects the yield and quality of Tartary buckwheat. The physicochemical characteristics of starch represent the important parameters of Tartary buckwheat quality. The effects of different levels of nitrogen application at different levels (0, 45, 135 and 225 kg/ha in 2015 and 0, 90, 180 and 270 kg/ha in 2017) on the physicochemical characteristics of Tartary buckwheat starch were studied. The amylose content, particle size and retrogradation of Tartary buckwheat starch with nitrogen were lower than those of without nitrogen. The structure complexity, pasting temperature, gelatinization enthalpy, relative crystallinity, light transmittance and solubility of the former were higher than those of the latter. Nitrogen application did not change the 'A'-type crystalline pattern of Tartary buckwheat starch. This study indicated that nitrogen level and years and the interactions among nitrogen fertilizer levels and years significantly affected the physicochemical properties of Tartary buckwheat starch. These integrated results also provided information about the management of fertilization conditions to obtain starches with special properties for applications in food or nonfood industries. [ABSTRACT FROM AUTHOR]

Given study evaluates the cardioprotective effect of crocetin in myocardial infracted (MI) rats. MI was produced by administering isoproterenol (90 mg/kg/day, i.p.) in rats for two consecutive days. all the animals were divided in to four groups such as control group receives only saline; MI group which receives only isoproterenol and crocetin treated group which receives crocetin (50, 100 and 200 mg/kg/day, p.o.) for the duration of 15 days. At the end of dosing left ventricular functions was assessed to estimate its effect on cardiac functions. Catalase (CAT), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), creatine kinase (CK-MB), lactate dehydrogenase (LDH) and inflammatory cytokines were determined in the cardiac tissue homogenate. Histopathology study was also carried out using hematoxylin and eosin staining. Immunohistochemistry was done for the estimation of Caspase-3, Bcl-2, Bax and Nrf-2 level in the myocardial tissues of MI rats. Result of the study suggested that GSH, CAT, CK-MB, and LDH were (p < 0.01) increased in the tissue homogenate of crocetin treated group than MI group. However crocetin significantly (p < 0.01) decreases the level of MDA and activity of SOD in the tissue homogenate than MI group. It was observed that treatment with crocetin attenuates the level of inflammatory cytokines in the myocardial tissues of MI rats. Moreover level of caspase-3, Bax and Nrf-2 significantly reduced and Bcl-2 enhanced in the myocardial tissues of MI rats than MI group. The altered cellular architecture of heart tissue sections in the myocardial infracted rats were reversed by administration of crocetin treatment. Taking all these data together, it may be suggested that the crocetin act as a possible protective agent in myocardial infarction by decreasing oxidative stress and inflammatory cytokines and thereby attenuates the apoptosis of myocardial cells. [ABSTRACT FROM AUTHOR]

This study develops a decision model to assist bridge authorities in determining a preferred maintenance prioritization schedule for a degraded bridge network in a community that optimizes the performance of transportation systems within budgetary constraints at a regional scale. The study utilizes network analysis methods, structural reliability principles and meta-heuristic optimization algorithms to integrate individual descriptive parameters such as bridge capacity rating, condition rating, traffic demand, and location of the bridge, into global objective functions that define the overall network performance and maintenance cost. The performance of the network is measured in terms of travel time between all possible origin-destination (O-D) pairs. In addition to the global budgetary constraint, the optimization is also conditioned on local constraints imposed on traffic flow by insufficient load carrying capacity of deficient bridges. Uncertainties in traffic demands, vehicle weights and maintenance costs are also considered in the problem formulation. Two project priority indices are introduced – the static priority index (SPI), defined as a function of the difference in network travel time between block running (with reduced load carrying capacity before repair) and smooth running (design-level load carrying capacity after repair) of a bridge, and the dynamic priority index (DPI) defined as the likelihood of a bridge being selected for repair when the budget is fixed and the uncertainties governing the performance of the transportation network are considered. Finally, this decision model is illustrated with a hypothetical network with 160 bridges. [ABSTRACT FROM AUTHOR]

Transportation infrastructure has been identified by the US Department of Homeland Security as one of sixteen critical infrastructure systems essential to the well-being of modern societies. In this study, we propose a resilience-based framework for mitigating risk to surface road transportation networks. We utilize recent developments in modern network theory to introduce a novel metric based on system reliability and network connectivity to measure resilience-based performance of a road transportation network. The formulation of this resilience-based performance metric (referred in the paper as WIPW), systematically integrates the network topology, redundancy level, traffic patterns, structural reliability of network components (i.e. roads and bridge) and functionality of the network during community’s post-disaster recovery, and permits risk mitigation alternatives for improving transportation network resilience to be compared on a common basis. Using the WIPW as a network performance metric, we propose a project ranking mechanism for identifying and prioritizing transportation network retrofit projects that are critical for effective pre-disaster risk mitigation and resilience planning. We further present a decision methodology to select optimal solutions among possible alternatives of new construction, which offer opportunities to improve the resilience of the network by altering its existing topology. Finally, we conclude with an illustration that uses the WIPW as the performance metric to support risk-based mitigation decisions using a hypothetical bridge network susceptible to seismic hazards. [ABSTRACT FROM AUTHOR]

The regulation of GPX4 by A 1 AR and A 2b AR was investigated, and whether the inhibition of A 1 AR and A 2b AR on ferroptosis of myocardial cell is related to GPX4 was also discussed. we constructed a rat model of myocardial ischemia and reperfusion (MIR) model and hypoxia/reoxygenation (H/R) model of H9C2 cells, and MIR rats were intraperitoneally injected with A1AR and A2bAR agonists and antagonists. TTC staining, DHE, TUNEL, western blot experiments, immunohistochemistry assay were implemented to analyze the influence of A 1 AR and A 2b AR on ferroptosis and potential role of GPX4. To further authenticate the result of non-specific agonists and antagonists, we transfected siRNA interference or overexpression vectors into cells. CCK8, flow cytometry and western blot were performed to evaluate cell proliferation and apoptosis, and the expression of GPX4 and ferroptosis-related proteins. The experimental results showed that reduced expression of A 1 AR, A 2b AR and GPX4 was found after MIR. A 1 AR and A 2b AR activation by agonists increased GPX4 expression and decreased production of lipid ROS, further inhibiting apoptosis of cardiomyocytes. In addition, we also analyzed the effect of A 1 AR and A 2b AR on ferroptosis-related proteins. We found that expression of FIH1 protein increased and expression of ACSL4 and NOX1 proteins decreased. Consistent with results in vivo, cellular data also indicated that A 1 AR and A 2b AR overexpression could increase proliferation ability of H9C2, and inhibit apoptosis and ROS production, upregulate GPX4 and FIH1, and downregulate ACSL4 and NOX1. A 1 AR and A 2b AR could regulate GPX4, thereby affecting ferroptosis of cardiomyocytes in a rat model of MIR. • The relationship between adenosine receptors and ferroptosis was firstly discussed. • We studied whether ARs regulate GPX4 inhibit ferroptosis of myocardial cell in MIR. • And we also analyzed the protection of A1 and A2b Adenosine receptors against myocardial infarction. [ABSTRACT FROM AUTHOR]

Slope failure often occurs during the spring thawing period in seasonally frozen areas, and it was concluded that the bolts did not perform as well as designed. Such failure disasters introduce an urgent need for the effective prediction of bolt performance for bolt design. Although many experiments exist to investigate the performance of bolts after exposure to freeze–thaw cycles, predictions of bolt performance under such environments are lacking. In this paper, the analytical relations for predicting the axial forces and shear stresses distributed along full-length bonded rock bolts when subjected to freeze–thaw processes were reported. The reported relations take advantage of Mindlin's displacement solution and consider the influence of crack development in rock on the elastic modulus during freeze–thaw processes. A freeze–thaw cycling factor , with proper consideration of the impact of freeze–thaw processes, is introduced and incorporated into Mindlin's displacement solution. A comparison between the predictions and experimental observations demonstrates the ability of the reported relations to accurately predict the performance (i.e., force and stress distributions) of full-length bonded rock bolts. The reported relations provide a simple, practical tool for accurately estimating the bolt performance under freeze–thaw processes. The weaknesses of the reported relations are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we report realization of a spectrum-adjustable random fiber laser (RFL) though central pumping in a single mode fiber (SMF), wherein a fiber Bragg grating (FBG) is mounted in the middle to control the laser output. By adjusting the feedback of the FBG bi-directionally, random lasing with adjustable spectra is realized. A unique hybrid dual-peak lasing spectrum with one peak regulated by the FBG and the other peak determined by distributed Rayleigh scattering (RS) feedback is achieved. It is also revealed that the FBG defining lasing peak is sensitive to temperature variation while the other peak is insensitive to temperature variation. [Copyright &y& Elsevier]