The effects of C element on the microstructure and properties of CoCrFeNiC,. high entropy alloys （x denoted the atomic fraction of C element at 0, 0.05, 0.1, 0.2, 0.3, and 0.5） were investigated. The ...equal molar CoCrFeNi alloy with FCC structure exhibits high ductility but weak strength. With the addition of C element, both the hardness and strength of the CoCrFeNiCx high entropy alloys increase as well as the wear resistance. The solution strengthening and the lbrmation of hard carbide phase are the main thctor for the improved strength, hardness and wear resistance of CoCrFeNiC~ high entropy alloys.
Brownfields are an important part of urban land resources. Strengthening the governance and redevelopment of brownfields is significant to environmental protection, high-quality urban development and ...sustainable development. However, due to the complexity and harmfulness of brownfield pollution, the hasty, untimely, and blind development can cause serious consequences. It is infeasible to pay more attention to development than governance or vice versa. In this paper, aiming at brownfield redevelopment evaluation, we introduced the Wuli-Shili-Renli (WSR) system methodology, an oriental system thought combining qualitative and quantitative analyses, comprehensively analyzed the influencing factors of brownfields from three dimensions of Wuli, Shili and Renli, and constructed the evaluation index system of brownfield redevelopment. To avoid much subjectivity in the evaluation process, we established the evaluation model of brownfield redevelopment using the catastrophe progression method. Taking the renovation project of Shanghai Xintiandi in 1999-2001 as a reference, the evaluation index system and evaluation model were applied to the renovation project of Wenjia Street in Qingyang District, Chengdu, Sichuan Province, China in 2022, and the results provided a good basis for the decision-making process.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background. This study was aimed to investigate the application of SARS-CoV-2 IgM and IgG antibodies in diagnosis of COVID-19 infection. Method. This study enrolled a total of 178 patients at ...Huangshi Central Hospital from January to February 2020. Among them, 68 patients were SARS-CoV-2 infected, confirmed with nucleic acid test (NAT) and CT imaging. Nine patients were in the suspected group (NAT negative) with fever and other respiratory symptoms. 101 patients were in the control group with other diseases and negative to SARS-CoV-2 infection. After serum samples were collected, SARS-CoV-2 IgG and IgM antibodies were tested by chemiluminescence immunoassay (CLIA) for all patients. Results. The specificity of serum IgM and IgG antibodies to SARS-CoV-2 was 99.01% (100/101) and 96.04% (97/101), respectively, and the sensitivity was 88.24% (60/68) and 97.06% (66/68), respectively. The combined detection rate of SARS-CoV-2 IgM and IgG antibodies was 98.53% (67/68). Conclusion. Combined detection of serum SARS-CoV-2 IgM and IgG antibodies had better sensitivity compared with single IgM or IgG antibody testing, which can be used as an important diagnostic tool for SARS-CoV-2 infection and a screening tool of potential SARS-CoV-2 carriers in clinics, hospitals, and accredited scientific laboratories.
Introduction: Probiotics have been recognized for their various biological activities, including antioxidant and anti-inflammatory properties. This study investigates the therapeutic effect of a ...novel probiotic formula, BLLL, consisting of Bifidobacterium breve , Lactobacillus plantarum , Lactobacillus paracasei , and Lactobacillus helveticus , on chronic stress-induced depression-like behaviors in mice. Methods: The BLLL formula or phosphate-buffered saline (PBS) was given orally at a dose of 2, 4, or 8 × 10 10 CFU/kg once daily for 10 days in mice treated with chronic unpredictable stress (CUS) treated or vehicle. Depression-like behaviors were assessed using the sucrose preference test (SPT), the forced swimming test (FST), and the tail suspension test (TST). The mRNA and/or protein expression of interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), IL-4, IL-10, and chitinase-3-like protein 3 (CHI3L1, also known as Ym-1), as well as the concentration of nitrite, malondialdehyde (MDA), glutathione (GSH), and brain-derived neurotrophic factor (BDNF) in the hippocampus and medial prefrontal cortex were examined. Results: The BLLL formula treatment at a dose of 8 × 10 10 CFU/kg, but not at a dose of 2 or 4 × 10 10 CFU/kg, improved CUS-induced depression-like behaviors in mice, as shown by the decrease in immobility time in the TST and FST and the increase in sucrose intake in the SPT. Further analysis revealed that BLLL treatment suppressed the CUS-induced increase in IL-1β, IL-6, and TNF-α mRNA and protein levels, as well as the CUS-induced decrease in IL-4, IL-10, and Ym-1 mRNA and/or protein levels in the hippocampus and medial prefrontal cortex. In addition, treatment with the BLLL formula countered the CUS-induced increase in nitrite and MDA levels and the CUS-induced decrease in GSH content and BDNF concentration in the hippocampus and medial prefrontal cortex. Conclusion: These results demonstrate that the novel probiotic formula BLLL ameliorates chronic stress-induced depression-like behavior in mice by suppressing neuroinflammation and oxido-nitrosative stress in the brain.
cAMP is well known to regulate exocytosis in various secretory cells, but the precise mechanism of its action remains unknown. Here, we examine the role of cAMP signaling in the exocytotic process of ...insulin granules in pancreatic beta cells. Although activation of cAMP signaling alone does not cause fusion of the granules to the plasma membrane, it clearly potentiates both the first phase (a prompt, marked, and transient increase) and the second phase (a moderate and sustained increase) of glucose-induced fusion events. Interestingly, all granules responsible for this potentiation are newly recruited and immediately fused to the plasma membrane without docking (restless newcomer). Importantly, cAMP-potentiated fusion events in the first phase of glucose-induced exocytosis are markedly reduced in mice lacking the cAMP-binding protein Epac2 (Epac2ko/ko). In addition, the small GTPase Rap1, which is activated by cAMP specifically through Epac2 in pancreatic beta cells, mediates cAMP-induced insulin secretion in a protein kinase A-independent manner. We also have developed a simulation model of insulin granule movement in which potentiation of the first phase is associated with an increase in the insulin granule density near the plasma membrane. Taken together, these data indicate that Epac2/Rap1 signaling is essential in regulation of insulin granule dynamics by cAMP, most likely by controlling granule density near the plasma membrane.
The observability of the leader robot system and the leader-follower formation control are studied. First, the nonlinear observability is studied for when the leader robot observes landmarks. Second, ...the system is shown to be completely observable when the leader robot observes two different landmarks. When the leader robot system is observable, multi-robots can rapidly form and maintain a formation based on the bearing-only information that the follower robots observe from the leader robot. Finally, simulations confirm the effectiveness of the proposed formation control.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A series of Mn-Co/TiO2 catalysts were prepared by wet impregnation method and evaluated for the oxidation of NO to NO2. The effects of Co amounts and calcination temperature on NO oxidation were ...investigated in detail. The catalytic oxidation ability in the temperature range of 403-473 K was obviously improved by doping cobalt into Mn/TiO2. These samples were characterized by nitrogen adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM) and hydrogen temperature programmed reduction (H2-TPR). The results indicated that the formation of dispersed Co3O4*CoMnO3 mixed oxides through synergistic interaction between Mn-O and Co-O was directly responsible for the enhanced activities towards NO oxidation at low temperatures. Doping of Co enhanced Mn4+ formation and increased chemical adsorbed oxygen amounts, which also accelerated NO oxidation.
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•MC-LR entered HT-22 cells in a concentration-dependent pattern.•MC-LR exposure induced oxidative stress in HT-22 cells.•MC-LR exposure induced mitochondrial fragmentation in HT-22 ...cells.•MC-LR exposure could induce apoptotic way of HT-22 cells death.•MC-LR exposure induced mitochondrial fragmentation in hippocampus of mice and neurodegeneration.
Microcystin–leucine–arginine (MC-LR) can cross the blood–brain barrier (BBB) and demonstrate potent acute hippocampal neurotoxicity. Chronic exposure to MC-LR has been confirmed to cause learning and memory deficits in mice, but the potential molecular mechanism of MC-LR-caused neurotoxicity is still unclear. In this research, we observed that MC-LR induced oxidative stress, mitochondrial fission and apoptosis in HT-22 hippocampal neurons. Moreover, further studies identified that MC-LR induced mitochondrial fragmentation via activating Dynamin-related protein 1 (Drp1) and Mitochondrial fission factor (Mff), contributing to apoptosis of hippocampal neuronal cells. The observed effects were associated with increased intracellular Ca2+ and reduced activity of protein phosphatases 2A (PP2A) as results of MC-LR exposure in hippocampal neuron cells. Ca2+ activates CaMK II and Akt to enhance phosphorylation of Drp1 at Ser616 residue. Inhibition of PP2A activity increased AMPK activity to mediate phosphorylation of Mff. Our data proved that MC-LR can cause mitochondrial fragmentation in hippocampal neurons, which provides novel perception to explore the underlying molecular mechanism associated with MC-LR-induced neurotoxicity and Alzheimer’s disease-like changes.
Alzheimer's disease (AD) is a neurodegenerative process characterized by loss of neurons in the hippocampus and cerebral cortex, leading to progressive cognitive decline. Pathologically, the hallmark ...of AD is accumulation of "senile" plaques composed of amyloid-β (Aβ) protein surrounding neurons in affected regions. Despite extensive research into AD pathogenesis and therapeutic targets, there remains no breakthroughs in its management. In recent years, there has been a spark of interest in the connection between the brain and gastrointestinal tract, referred to as the brain-gut axis, and its potential implications for both metabolic and neurologic disease. Moreover, the gastrointestinal flora, referred to as the microbiome, appears to exert significant influence over the brain-gut axis. With the need for expanded horizons in understanding and treating AD, many have turned to the brain-gut-microbiome axis for answers. Here we provide a review of the brain-gut-microbiome axis and discuss the evidence supporting alterations of the axis in the pathogenesis of AD. Specifically, we highlight the role for the microbiome in disruption of Aβ metabolism/clearance, increased permeability of the blood-brain barrier and modulation of the neuroinflammatory response, and inhibition of hippocampal neurogenesis. The majority of the above described findings are the result of excellent, albeit basic and pre-clinical studies. Therefore, we conclude with a brief description of documented clinical support for brain-gut-microbiome axis alteration in AD, including potential microbiome-based therapeutics for AD. Collectively, these findings suggest that the brain-gut-microbiome axis may be a "lost link" in understanding and treating AD and call for future work.
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