The stormwater system is an important infrastructure for the city, playing an important safety role in reducing and removing water from roads and avoiding urban flooding. With the acceleration of ...urbanization and the accentuation of urban heat island effect, urban surface runoff shows the trend of high flow rate and fast flow rate, which leads to the increase of drainage load of urban stormwater system and the increase of risk of urban flooding. Therefore, it is necessary to adopt a scientific method to conduct a comprehensive analysis of the overall drainage capacity and safe conveyance capacity of the urban stormwater system, so as to do the preliminary paving work for the transformation of the existing stormwater system and improve the urban drainage capacity. In this paper, based on the analysis of the current status of urban stormwater system, the concept of urban stormwater system vulnerability is proposed and the indicators of stormwater system vulnerability are determined.
This study introduced a simplified thermodynamic model based on the regularized phase field method for simulating the thermally induced fractures of rocks pretreated by microwave. A thermo-mechanical ...model comprises three main parts developed to evaluate the fractures: the heat generation of the rock specimen is determined via the heat balance equation; the calculation of thermally induced stress is performed in the second part by taking into account the thermal stress due to temperature change; the third part calculates the fracture induced by microwave heating using the phase field equation. Combining these three parts enables simulations of rock fractures due to thermally induced stress. The first simulation is the quenching test of ceramics to validate the robustness of the phase field method in modelling the thermo-mechanical fracture. Then, examples of microwave-induced fracture are presented and discussed in comparison with microwave test results. A good agreement is achieved from the results of numerical analysis and experiments, which proves the feasibility of the proposed thermo-mechanical coupling fracture (phase field) model for the simulation of thermal-mechanical fractures. It is further found that the power level is crucial in influencing the fractures given the same energy input. More specifically, a higher power level leads to an increased non-uniformity of a thermal gradient, which, as a result, leads to a higher stress gradient and more fractures generated eventually. Furthermore, the energy utilization ratio also benefits under a more intensive microwave power level. The developed model quantitatively enriches the understanding of fractures produced by microwave irradiation and advances the application of the microwave-assisted rock breakage technique in industry and academics.
Alzheimer's disease (AD) is one of the most common types of age-related dementia worldwide. In addition to extracellular amyloid plaques and intracellular neurofibrillary tangles, dysregulated ...microglia also play deleterious roles in the AD pathogenesis. Numerous studies have demonstrated that unbridled microglial activity induces a chronic neuroinflammatory environment, promotes β-amyloid accumulation and tau pathology, and impairs microglia-associated mitophagy. Thus, targeting microglia may pave the way for new therapeutic interventions. This review provides a thorough overview of the pathophysiological role of the microglia in AD and illustrates the potential avenues for microglia-targeted therapies, including microglial modification, immunoreceptors, and anti-inflammatory drugs.
The search of multifunctional epoxy nanocomposites with both strength and toughness combined with smart features such as electrical conductivity is essential in design of advanced materials. In this ...work, by utilizing a binary nanofiller strategy, both strength and toughness as well as high electrical conductivity are obtained in epoxy with trace nanopolystyrene grafted with epichlorohydrin (nano g-PS) to facilitate the dispersion of multi-walled carbon nanotubes (MWCNTs). The increased tensile strength (37.6%) and flexural strength (34.4%) are acquired in nano g-PS (0.0677 vol%)/MWCNTs (0.0335 vol%)/epoxy in contrast to pure epoxy. A remarkably improved tensile toughness up to 379.2% and an increased elongation at break up to 208.3% are obtained in this epoxy nanohybrid. The synergistic interactions among nano g-PS, MWCNTs and epoxy matrix as well as the state transition of nano g-PS from glassy state to fluid state provide an improved dispersion of nanofillers which is responsible for the increased electrical conductivity and enhanced mechanical properties. The decreased surface resistivity allows these nanohybrids to sufficiently dissipate surface charges as an antistatic material. This work provides an effective way to disperse carbon nanotubes with small amount of thermoplastic PS to simultaneously strengthen and toughen the thermosetting epoxy while introducing highly conductive function.
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Rural migrants usually suffer from major disease risks, but little attention had been paid toward the relationship between self-employment behavior and health status of rural migrants in China. ...Present study aims to explore the causal effect of self-employment behavior on rural migrants' sub-health status and chronic disease. Two research questions are addressed: does self-employment status affect the sub-health status and chronic disease of rural migrants? What is potential mechanism that links self-employment behavior and health status among rural migrants in China?
The dataset from the 2017 National Migrants Population Dynamic Monitoring Survey (NMPDMS-2017) was used to explore the causal effect. Logit regression was performed for the baseline estimation, and linear probability model with instrument variable estimation (IV-LPM) was applied to correct the endogeneity of self-employment. Additionally, logit regression was conducted to explore the transmission channel.
Self-employed migrants were more susceptible to sub-health status and chronic disease, even when correcting for endogeneity. Moreover, self-employed migrants were less likely to enroll in social health insurance than their wage-employed counterparts in urban destinations.
Self-employed migrants were more likely to suffer from sub-health status and chronic disease; thus, their self-employment behavior exerted a harmful effect on rural migrants' health. Social health insurance may serve as a transmission channel linking self-employment and rural migrants' health status. That is, self-employed migrants were less prone to participate in an urban health insurance program, a situation which leaded to insufficient health service to maintain health.
Facial action unit (AU) detection is an important task in affective computing and has attracted extensive attention in the field of computer vision and artificial intelligence. Previous studies for ...AU detection usually encode complex regional feature representations with manually defined facial landmarks and learn to model the relationships among AUs
graph neural network. Albeit some progress has been achieved, it is still tedious for existing methods to capture the exclusive and concurrent relationships among different combinations of the facial AUs. To circumvent this issue, we proposed a new progressive multi-scale vision transformer (PMVT) to capture the complex relationships among different AUs for the wide range of expressions in a data-driven fashion. PMVT is based on the multi-scale self-attention mechanism that can flexibly attend to a sequence of image patches to encode the critical cues for AUs. Compared with previous AU detection methods, the benefits of PMVT are 2-fold: (i) PMVT does not rely on manually defined facial landmarks to extract the regional representations, and (ii) PMVT is capable of encoding facial regions with adaptive receptive fields, thus facilitating representation of different AU flexibly. Experimental results show that PMVT improves the AU detection accuracy on the popular BP4D and DISFA datasets. Compared with other state-of-the-art AU detection methods, PMVT obtains consistent improvements. Visualization results show PMVT automatically perceives the discriminative facial regions for robust AU detection.
The implementation of the “Blue Basic Farmland” system for farming ocean is a crucial strategy to ensure food security. This study simulates and analyzes the impact of government fishery subsidies on ...promoting “Blue Basic Farmland” construction. A tripartite evolutionary game model involving the government, fishermen and fishery enterprises was used”. Subsequently, the fishery subsidy strategy of “Blue Basic Farmland” construction was simulated and analyzed. The following findings are derived. First, fishery subsidies contributed to “Blue Basic Farmland” construction by promoting the participation of fishing enterprises and supporting fishermen. Second, the amounts of fishery subsidies were not the high the better, and different amounts of fishery subsidies had varying effects. Third, subsidizing fishery enterprises was more effective in promoting the construction of “Blue Basic Farmland” compared to subsidizing fishermen. In light of these findings, we proposed the following policy recommendations. The government ought to establish subsidies specifically tailored for “Blue Basic Farmland” construction, while also judiciously controlling the subsidies amounts. Moreover, the focus of these subsidies should be directed towards supporting fishery enterprises.
The plant-derived toxin ricin is classified as a type 2 ribosome-inactivating protein (RIP) and currently lacks effective clinical antidotes. The toxicity of ricin is mainly due to its ricin toxin A ...chain (RTA), which has become an important target for drug development. Previous studies have identified two essential binding pockets in the active site of RTA, but most existing inhibitors only target one of these pockets. In this study, we used computer-aided virtual screening to identify a compound called RSMI-29, which potentially interacts with both active pockets of RTA. We found that RSMI-29 can directly bind to RTA and effectively attenuate protein synthesis inhibition and rRNA depurination induced by RTA or ricin, thereby inhibiting their cytotoxic effects on cells in vitro. Moreover, RSMI-29 significantly reduced ricin-mediated damage to the liver, spleen, intestine, and lungs in mice, demonstrating its detoxification effect against ricin in vivo. RSMI-29 also exhibited excellent drug-like properties, featuring a typical structural moiety of known sulfonamides and barbiturates. These findings suggest that RSMI-29 is a novel small-molecule inhibitor that specifically targets ricin toxin A chain, providing a potential therapeutic option for ricin intoxication.
Hydrodynamic sorting has been shown to strongly influence the composition and age of organic carbon (OC) during sediment transport and burial in the marine environment, yet sorting effects on ...terrestrial OC (OCterr) in fluvial systems remain poorly understood. We conducted size fractionation of suspended particle samples from the lower Yellow River, China, and examined variations in mass distribution and carbon isotopic (δ13C and Δ14C) composition of bulk OC and specific biomarkers among grain size fractions in order to investigate the influence of hydrodynamic sorting and selective transport on organic matter export. In general, the 16–32 μm and 32–63 μm fractions contributed the most of sediment mass while the majority of the OC resided in the 16–32 μm fraction. Over 80% of OC and n-fatty acids (FAs) were concentrated in <32 μm fractions. Significant differences in OC%, surface area (SA), Δ14COC, n-FAs contents, and compound-specific 13C and 14C compositions were found among size fractions. Of particular note was a progressive decrease of Δ14C values (i.e., increase in 14C age) of long-chain (C26+28+30) FAs with decreasing grain size. Taken together, the bulk and molecular characteristics imply two distinct types of selective OCterr transport in the Yellow River. Coarser particles (>32 μm), characterized by relatively low SA, OC%, and Δ14COC values, but higher Δ14C values of C26+28+30 FAs, are inferred to reflect a combination of bedrock-derived detrital sediment and fresh vascular-plant material (e.g., plant fragments). In contrast, finer particles (<32 μm), exhibiting higher SA, OC%, and lower Δ14C26+28+30FAs values, reflect preferential transport of pre-aged, mineral soil-derived OC that is susceptible to repeated mobilization, as well as widespread dispersal in marginal seas. The latter, once buried in marine sediments, could account for the high burial efficiency of OCterr in the adjacent Bohai Sea and Yellow Sea. Thus, hydrodynamic sorting processes induce heterogeneity of composition and selective transport of OC. Bulk and molecular 14C measurements of size-fractionated particles facilitate both elucidation of these processes and assessment of their impact on OC cycling in (and export from) rivers.
The
sp. BN6-4 capable of degrading high concentrations of pyridine was isolated from the coking sludge. The removal rate of BN6-4 to 1,000 mg/L pyridine during 48 h was 97.49 ±1.59%. The primary ...intermediate metabolites of pyridine degradation by strain BN6-4 were identified by gas chromatography-mass spectrometry (GC-MS), including N-Ethylurea, acetamidoacetaldehyde, and N-Hydroxymethylacetamide, etc
Subsequently, two different biodegradation pathways of pyridine were proposed. First, the hydroxylation of pyridine to form the intermediates pyridin-2(1H)-one and 5,6-dihydropyridine-2,5-diol, the former undergoing oxidative ring opening and the latter oxidative ring opening via N-C2 and C2-C3 ring opening to ammonia and carbon dioxide. Furthermore, the organic matter was greatly degraded by the bioremediation of real coking wastewater using BN6-4. This study enriched the microbial resource for pyridine degradation and provided new insights about the biodegradation pathway of pyridine, which is of great significance for the pyridine pollution control and coking wastewater treatment.
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