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A type of reduced graphene oxide (rGO)/SnIn4S8 (SIS) nanocomposites was successfully fabricated by a facile and efficient microwave-assisted method. Their morphology, structure, composition, and optical performance were investigated by different analytical techniques, respectively. The results indicated that rGO had an important effect on the structure of photocatalysts. As the content of rGO increases, the unchin-like microsphere structure of rGO/SIS evolved gradually into aggregated nanosheet structure. The photocatalytic degradation experiments were carried out under visible light irradiation. The results demonstrated rGO/SIS-2 nanocomposites exhibited higher photocatalytic activity toward the degradation of RhodamineB than that of SIS, rGO/SIS-1 as well as rGO/SIS-3. Meanwhile, the mineralization efficiency of Rhodamine B (RhB) can reach up to 73.8% within 30 min. Interestingly, rGO/SIS-2 nanocomposites exhibited excellent recycle stability with 96% removal efficiency of RhB after three cycles. The enhanced photocatalytic activity of rGO/SIS-2 nanocomposites should be attributed to the strong interaction of rGO and SIS, the decrease of band gap energy, the enhanced visible light absorption, and excellent electrons’ mobility of rGO, thereby promoting charge separation. Finally, the mechanism of rGO/SIS nanocomposites for the degradation of RhB has been also proposed. This work provides a facile and efficient pathway to prepare SIS-based nanocomposites with enhanced catalytic efficiency by combining the advantages of microwave-assisted heating and incorporating carbon-based nanomaterials for the degradation of organic pollutants in visible light irradiation.

The aim of this study is to describe the novel epidemiological and clinical characteristics of influenza A-induced severe pneumonia occurring after the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to further assess its potential risk factors for mortality.

A scorpion like robot is designed for temperature measurement of coke ovens in response to the harsh environment on the top of the coke oven, low accuracy and efficiency of manual temperature measurement. This study mainly analyzes the design based on the robot's leg walking mechanism. Firstly, the biomimetic structure of the scorpion is referred to complete the modeling of the overall structure of the coke oven temperature measuring robot and the design of its legs. Stress analysis indicates that it operates safely and stably during the temperature measurement process. Then the D-H coordinate system of the robot's kinematic structure is established, and the forward and inverse kinematics of its legs are analyzed. Then, Matlab is used to plan the Cartesian space trajectory of the legs and Adams is used to simulate the gait of the leg joints, indicating that the motion curves of the leg trajectory planning and gait simulation are almost identical and running smoothly. The experiment shows that the actual error of the temperature measurement robot's movement is maintained within 2 mm and runs smoothly. This lays an important foundation for the development of the overall system of the coke oven temperature measurement robot in the future.

The ZrC-SiC multiphase ceramic precursor of PZCS with abundant active cross-linking sites was prepared by a dehydrocoupling reaction between polyzrocarbonane (PZC) and polycarbosilane (PCS). The ceramization mechanism of PZCS and the composition and structure of the final ceramic were studied. The results reveal that the ceramic yield of PZCS (71.84%, mass fraction, the same below) is significantly higher than that of PZC (51.40%) or PCS (53.46%) precursor at 850 ℃, due to the promoted crosslinking of active groups during the ceramization process. Meanwhile, under the catalysis of Zr-Cp, the short-range carbon and Zr, Si elements are directly converted to carbide ceramics through the synergistic transformation of two polymers in PZCS, avoiding the adverse effects of carbon thermal reduction to the ceramics, and effectively reducing the sintering temperature. The ZrC-SiC nanocomposite ceramic with both high temperature resistance and oxidation resistance components is prepared after pyrolysis of PZCS. The generation of ZrC and SiC phases could inhibit crystallization and refine the grain size, of which the ZrC grain size is 25.4 nm. Moreover, the generation of ZrC-SiC nanocomposite structure would be beneficial for improving the comprehensive performance of ultra-high temperature ceramics.

As a kind of rechargeable batteries, alkali metal-ion battery is one of the important energy storage devices at present. Due to the advantages of enhanced energy density, high work potential, no "memory effect", small self-discharge, environment-friendly, alkali metal-ion batteries have attracted extensive attention in recent years. Electrode material is one of the most important factors that influence the electrochemical performances of alkali metal-ion batteries. Therefore, the key to the improvement of alkali metal-ion batteries is to seek electrode materials with high specific capacity and stable structures. Quantum dots/carbon composites (QDs/C), integrating the advantages of quantum dot materials and carbon materials have turned out to be outstanding candidates for electrode materials of alkali metal-ion batteries. In this work, a brief introduction of quantum dot materials was given at first, and then the progress of QDs/C, including element QDs/C, compound QDs/C and heterostructure QDs/C in alkali metal-ion batteries, was summarized respectively. The advantages and disadvantages of QDs/C as electrode materials of alkali metal-ion batteries were discussed in the last part.In view of the shortcoming, the future development goal was proposed: (1)Exploring the innovative approach to slove the agglomeration of quantum dots and the relative composites; (2)Researching the structure and property of SEI film to improve the initial coulombic efficiency; (3)Clarifying the reaction mechanism to obtain the better electrochemical performance.

Aiming at the low efficiency of temperature measurement in coke oven factory, a type of scorpion-like composite robot is designed to measure temperature in coke ovens. The robot works in combination with the structural characteristics of the scorpion. It uses the scorpion's double pincers to lift the lid of the furnace and measures the temperature in the furnace with the infrared temperature measurement of the scorpion tail. In order to verify the rationality of the robot structure, the overall D-H structure of the composite robot is modeled by Matlab, the forward and inverse kinematics of the legs of the composite robot are analyzed, and the working space probability model of the infrared thermometer with both arms and tail is obtained by Monte Carlo method simulation. In order to verify the motion stability of the robot, the stable gait of the composite robot was obtained through Adams simulation. It lays a solid foundation for further robot research.

ObjectiveTo assess the ability of the inspection institutions of laboratory animals and to improve their detection levels through the implementation of the proficiency testing for the detection ability of Bordetella bronchiseptica, Pasteurella pneumotropica, Pasteurella multocida and Corynebacterium kutscheri in laboratory animals.MethodsAccording to the proficiency testing scheme approved by China National Accreditation Service for Conformity Assessment (CNAS), the two projects, NIFDC-PT-309 and NIFDC-PT-363 in 2021 and 2022 were set up, respectively. The samples of respiratory tract pathogens in laboratory animal were prepared by freeze-drying at low temperature. The samples were randomly grouped and numbered through the CNAS platform and issued to participating units after passing the homogeneity and stability tests. A work instruction was attached with each sample set. The inspection reports and original records were required to be submitted within the specified time. If the feedback results were consistent with the sample setting, the results were deemed as satisfactory, and if the feedback results were inconsistent or not submitted on time, the results were deemed as unsatisfactory.ResultsThere were 29 laboratories joined to NIFDC-PT-309, 27 laboratories (93.1%) achieved satisfactory test results. There were 30 laboratories joined to NIFDC-PT-363, the satisfaction rate is 100%.ConclusionLaboratory animal quality inspection institutions have the ability to detect respiratory pathogens, which gets steadily improved through the ability verification activities.

Solving the problem of agricultural water use efficiency is an effective means to understand the agricultural ecological civilization and food security. In order to balance the relationship between agricultural water efficiency and regional economic size, this study examines the agricultural water use efficiency in China based on the Super-SBM model of unexpected output. At the same time, the Spatial Durbin Model (SDM) was introduced to analyze the spatial spillover effect and try to find ways to improve agricultural water use efficiency from the perspective of influencing factors. The present study used the panel data of 30 provinces in China from 1998 to 2018 to obtain empirical results. The results show that (1) China's agricultural water resources’ utilization efficiency in 21 years has not remained high: the results showed that it was 0.496 in 1998, 0.572 in 2008, and 0.657 in 2018, but it is slowly rising which explains that the low efficiency is mainly caused by the low pure technical efficiency. (2) The overall agricultural water use efficiency in China is in a situation of spatial agglomeration but there has been a trend of shifting positive correlations to negative correlations among neighboring provinces. It found that in 1998, the sum of the number of `High-high agglomeration type' and `low-low agglomeration type' provinces was 20, and the sum of `low-high agglomeration type' and `high-low agglomeration type' provinces was 10. In 2018, the total number of `high-high agglomeration type' and `low-low agglomeration type' provinces decreased to 12, while the total number of `low-high agglomeration type' and `high-low agglomeration type' provinces increased to 18, which specifically manifested as a negative spillover effect. (3) During the research period, the province's agricultural fixed asset investment, fiscal expenditure on agriculture, forestry, and water affairs, the number of years of education of rural residents and the increase in crop sown area have positive impacts on the efficiency of agricultural water use in the province. Meanwhile the transfer of labor and increase in the disposable income of rural residents reduced the efficiency of agricultural water use in the province. Fixed agricultural investment, labor transfers, and financial expenditures for agriculture, forestry, and water affairs in neighboring provinces have negative impacts on the province's agricultural water use efficiency. The impact is specifically manifested as a negative spatial spillover effect. As a result, China's agriculture will move towards healthy and green development. Therefore, the efficiency of agricultural water use needs to be comprehensively improved. HIGHLIGHTS Agricultural water use efficiency and the spatial spillover effect.; Taking agricultural carbon emissions as an unexpected output.; The study used unexpected output Super-SBM model and SDM.; Agricultural water use efficiency among provinces shows a negative spatial spillover effect.;

Muscarinic acetylcholine receptors (MRs) play important roles in the regulation of hepatic fibrosis and the receptor agonists and antagonists can affect hepatocyte proliferation. However, little is known about the impact of M 3R subtypes and associated signaling pathways on liver injury. The aim of this study is to explore the function and mechanism of M 3R in the regulation of liver injury. We evaluate liver injury and detect the changes in related indexes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), hydroxyproline (HYP), and transforming growth factor-β1 (TGF-β1), after administration of an M 3R agonist. Western blot analysis and qRT-PCR show that the transcription factor Sp1 and long noncoding RNA (lncRNA) Gm2199 are also changed significantly. Rescue assay is performed to further confirm that M 3R contributes to the progression of hepatocyte proliferation through regulating Sp1 and Gm2199. The activated M 3R can specifically regulate Gm2199 by inhibiting the expression of Sp1. Meanwhile, Gm2199 directly regulates miR-212, and ERK is a potential target of miR-212. Collectively, these findings define a novel mechanism for activating M 3R to reverse liver injury, which affects hepatocyte proliferation through the Sp1/Gm 2199/miR-212/ERK axis.

In the context of new power system construction and the increasingly severe risks of urban security， urban power supply security has now become a top priority of urban security. Firstly， the risks faced by urban power grid in the context of new power system are analyzed. Then， major urban power supply accidents at home and abroad in recent years are sorted out， and the causes of each accident are analyzed. Then， the concept of risk transmission chain is put forward. Based on the evolution and conduction theory of the proposed risk chain， major urban power supply accidents at home and abroad in recent years are deduced， a detailed risk blocking scheme is formulated， and the grid risk assessment process and risk blocking deduction framework are put forward. Finally， the main measures and suggestions for improving the safety level of urban power supply are put forward. The proposed risk transmission chain and risk blocking measures have practical significance for consolidating urban power supply security in building a new power system.

The oncoprotein transcription factor paired box 2 (PAX2) is aberrantly expressed in cancers, but the underlying mechanism remains elusive. Prolyl hydroxylase 3 (PHD3) hydroxylates the proline residue of HIFα, mediating HIFα degradation. The von Hippel-Lindau protein (pVHL) is an E3 ligase which mediates ubiquitination and degradation of hydroxylated HIFα. PHD3 and pVHL are found to inhibit the expression of PAX2, however, the molecular mechanism is unclear. Here we demonstrate that PHD3 hydroxylates PAX2 at proline 9, which is required for pVHL to mediate PAX2 ubiquitination and degradation. Overexpression of PHD3 enhances prolyl hydroxylation, ubiquitination and degradation of PAX2 with little effect on those of PAX2(P9A). PHD3 does not influence PAX2 expression in VHL-null cells. pVHL binds to PAX2 and enhances PAX2 ubiquitination and degradation. However, pVHL does not bind with PAX2(P9A) and cannot enhance its ubiquitination and degradation. Our results suggest that proline 9 hydroxylation is a prerequisite for PAX2 degradation by pVHL. Functional studies indicate that introduction of PAX2 into PAX2-null COS-7 cells promotes cell proliferation, which is suppressed by co-expression of PHD3 but not by hydroxylase-deficient PHD3(H196A). PHD3 inhibits PAX2-induced, but not PAX2(P9A)-induced proliferation of COS-7 cells. These results suggest that PHD3 hydroxylates PAX2, followed by pVHL-mediated PAX2 ubiquitination and degradation. This study also suggests that PHD3 inhibits cell proliferation through downregulating PAX2.

ObjectiveTo analyze the epidemiological investigation results and emergency response to a coronavirus disease 2019 （COVID-19） epidemic in Shanghai.MethodsDescriptive epidemiological method was used to describe the epidemiological characteristics， such as population， time and spatial distribution of a COVID-19 epidemic on January 20， 2021 in Huangpu District of Shanghai. The advantages and disadvantages of the emergency response to this epidemic were analyzed.ResultsAll of the 22 cases were found by active screening， which included high-risk population screening （18.2%， 4/22）， medium-risk area screening （9.1%， 2/22）， and close contact population screening （72.7%，16/22）. The first 2 cases were detected by routine nucleic acid screening for staff in two hospitals. The confirmed cases appeared mostly during the first 3 days of the epidemic （45.5%，10/22）， and mainly distributed in the neighborhood C of Huangpu district. There were 6 key locations or regions of Huangpu District involved in this epidemic， and different control measures were adopted in these different regions according to the risk assessments. After precise epidemic prevention and control， it took only 14 days from the first to the last confirmed case of this epidemic （from January 21， 2021 to February 4， 2021）， and no new related cases appeared afterwards.ConclusionActive screening and early finding of COVID-19 cases play a key role in timely control of the epidemic， with the smallest cost， the highest efficiency and the most limited urban impact.

ObjectiveTo promote the development of domestic laboratory animal detection proficiency testing activities and testing levels by assessing self testing capabilities.MethodsThe National Institutes for Food and Drug Control participated in the International Council for Laboratory Animal Science (ICLAS) laboratory animal detection proficiency test (i.e. Performance Evaluation Program for Diagnostic Laboratories, PEP) in 2013—2020. PEP pathogenic bacteria samples were tested by culture, biochemical identification, PCR, and sequencing. Finally, the results were analyzed and summarized.ResultsThere were 40 samples in seven international PEP activities, involving 27 kinds of pathogenic bacteria. The coincidence rates of the seven results were 8/8, 2/2, 5/8, 9/9, 5/5, 6/7, and 1/1, respectively, including 33 pathogen detection items and 7 antibody detection items. Nine pathogens were missing from the national standards: Bordetella hinzii, Serratia marcescens, Corynebacterium mastitis, CAR (Cilia-associated respiratory) bacillus, Actinobacillus muris, Citrobacter freundii, Klebsiella oxytoca, Streptococcus agalactiae, and pathogenic Escherichia coli.ConclusionThrough participating in PEP, we can identify the differences between domestic and foreign standards in laboratory animal detection and the testing capabilities that we need to improve, expecting to be in line with international standards as soon as possible.

In view of problems of complicated calculation process, strong subjectivity and low accuracy in existing prediction methods of coal and gas outburst, a principal component-Fisher discriminant model was constructed and applied to the prediction of coal and gas outburst grade in a coal mine. Based on analysis of gas factors, coal structure and geological structure, the factors that affect coal and gas outburst of the coal mine included gas pressure, gas content and initial velocity of gas release and so on were obtained. On the basis of 23 groups measured data of coal and gas outburst of the coal mine, firstly, the principal component analysis model was used to do dimension reduction of influencing factors of the mine coal and gas outburst, 5 principal components with high index correlation were extracted. Then the 5 principal components were input into Fisher discriminant model, and the grade of coal and gas outburst of samples was predicted according to discriminant function. The application results show that the principal component-Fisher discriminant model has high credibility, and can accurately predict coal and gas outburst grade, the training sample accuracy is 100%, the predicted results of the tested sample are also consistent with the actual situation of coal and gas outburst of the coal mine, misjudgment rate of 0, which provides a new method of accurate prediction of coal and gas outburst.

In order to improve the forecasting accuracy of short-term power load，a power load forecasting approach based on ensemble empirical mode decomposition(EEMD)-sample entropy(SE) and genetic algorithm(GA) for RBF neural network optimization is proposed in the paper. The EEMD decomposition method is used to decompose the load sequence adaptively, and according to sample entropy to combine the subsequences with similar complexity, which effectively reduces the scale of operation. Based on the difference of sub-sequence complexity, the corresponding RBF neural network model is constructed. The genetic algorithm is used to avoid the neural network falling into the local optimal and convergence problem. Then the new sub-sequences are forecasted and superimposed to obtain the final forecasting result. The simulated results show that the prediction algorithm has a satisfactory prediction effect and meets the requirements of short-term power load forecasting.

In order to achieve dynamic and accurate measurement of multiple parameter information in farmland environment and improve the level of agricultural production, a weather monitoring station suitable for farmland environment is designed. Firstly, data acquisition hardware circuit based on Modbus protocol and data upload 4G gateway node circuit are designed. Secondly, the DMA controller is applied to the idle interrupt mode of the serial port to achieve efficient reception of Modbus data acquisition. Finally, the data is transmitted by the gateway node through the EDP protocol to the IoT cloud platform for analysis, evaluation and processing. The single site of the farmland meteorological monitoring station supports the real-time acquisition of 32-channel sensors, which solves the problem that the single node acquisition parameters are single and the acquisition cycle is long in the past deployment of farmland wireless sensor network nodes, and meets the needs of accurate agricultural farmland environment monitoring.

In order to prepare highly efficient and environmentally friendly photocatalysts, polyvinyl alcohol nanofibers coated with Al-doped ZnO precursor (AZO) were prepared via electrospinning and hydrothermal synthesis. Furthermore, AZO hollow nanofibers were successfully fabricated after calcination at high temperature. The morphology, structure and properties of the samples were characterized by scanning electron microscopy, X-ray diffractometer, X-ray photoelectron spectrometer, thermogravimetric analyzer and UV spectrophotometer. The results show that AZO hollow nanofibers have good photocatalytic degradation of dye.

A new type of environmental-friendly flexible nanofibers of aluminum doped zinc oxide (AZO) coated carbon (AZO@C) was successfully prepared by using polyvinyl alcohol (PVA) as raw materials. The as-spun PVA nanofibers were prepared via electrospinning and its water resistance was greatly improved after heat-treatment. Then, the PVA nanofibers with a layer of zinc aluminum hydroxide on the surface were synthesized by hydrothermal method. Thereafter, new AZO@C composite nanofibers was produced after sintering at 500℃ to the carbonization of PVA nanofibers and the dehydration of zinc aluminum hydroxide to form AZO nanoparticles. The structure and properties of the samples were characterized by Fourier-transform infrared spectrometer (FT-IR), thermal gravimetric analyzer (TGA) and scanning electron microscope (SEM). The average diameter of the AZO@C nanofibers is (320±45)nm. The photocatalytic property of the resultant composite fibers is demonstrated by degrading methyl orange under solar light.

Moiré superlattices based on van der Waals bilayers1-4 created at small twist angles lead to a long wavelength pattern with approximate translational symmetry. At large twist angles (θt), moiré patterns are, in general, incommensurate except for a few discrete angles. Here we show that large-angle twisted bilayers offer distinctly different platforms. More specifically, by using twisted tungsten diselenide bilayers, we create the incommensurate dodecagon quasicrystals at θt = 30° and the commensurate moiré crystals at θt = 21.8° and 38.2°. Valley-resolved scanning tunnelling spectroscopy shows disparate behaviours between moiré crystals (with translational symmetry) and quasicrystals (with broken translational symmetry). In particular, the K valley shows rich electronic structures exemplified by the formation of mini-gaps near the valence band maximum. These discoveries demonstrate that bilayers with large twist angles offer a design platform to explore moiré physics beyond those formed with small twist angles.