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BackgroundThe mental health problems of employees in administrative organs and public institutions are highly valued. However， there is a lack of understanding regarding the mental health status of employees in provincial and municipal administrative organs and public institutions in Qinghai region.ObjectiveTo analyze the anxiety and depression of employees in provincial and municipal administrative organs and public institutions in Qinghai region， so as to provide references for promoting their mental health and intervening in psychological problems.MethodsFrom October 23 to 28， 2022， a total of 3 096 employees in provincial and municipal administrative organs and public institutions in Qinghai region were enrolled using stratified cluster sampling technique， and were assessed using Self-rating Anxiety Scale （SAS） and Self-rating Depression Scale （SDS）.ResultsA total of 1797 （58.04%） employees in municipal and above administrative organs and public institutions in Qinghai region completed a valid questionnaire survey. Depressive symptoms were noted in 579 （32.22%）. SDS scores yielded statistical difference among the selected employees of different ethnicities， types of job positions and educational levels （F=9.074， 101.488， 4.477， P

ObjectiveTo understand the concentration levels of benzene， toluene and xylene in the workplaces of enterprises involved in benzene and benzene series in Jinshan District， and to provide the basis for the government to formulate key occupational disease prevention and control strategies.MethodsFrom 2016 to 2021， enterprises involved in benzene and benzene series were sampled individually， and the monitoring results of benzene and benzene series were statistically analyzed through workplace air sampling and laboratory detection.ResultsFrom 2016 to 2021， a total of 80 enterprises were monitored， and the total passing rate of individual monitoring was 87.50%， which decreased first and then increased. The difference was not statistically significant. A total of 387 individuals were sampled with a total passing rate of 95.61% and a detection rate of 73.38% （284 individuals）. The detection rates of benzene， toluene and xylene were 6.46%， 29.97% and 36.95%， respectively. The exceedance rates were 1.03%， 0.26% and 3.10%， respectively. Among the companies exceeding the standard， the metal products industry had the highest rate of exceedance （19.05%）. For individuals， those working in the printing and recording media reproduction industry had the highest rate of exceedance （10.26%）.ConclusionThe passing rate and detection rate of benzene and benzene series are relatively high in Jinshan District. The metal products industry and the printing and recording media reproduction industry have a higher exceedance rate of benzene and benzene series.

To investigate the mechanism of shear stress on endothelial cell dysfunction for providing a theoretical basis for the reduction of arteriovenous fistula dysfunction. The in vitro parallel plate flow chamber was used to form different forces and shear stress to mimic the hemodynamic changes in human umbilical vein endothelial cells, and the expression and distribution of krüppel-like factor 2 (KLF2), caveolin-1 (Cav-1), p-extracellular regulated protein kinase (p-ERK), and endothelial nitric oxide synthase (eNOS) were detected by immunofluorescence and real-time quantitative polymerase chain reaction. With the prolongation of the shear stress action time, the expression of KLF2 and eNOS increased gradually, while the expression of Cav-1 and p-ERK decreased gradually. In addition, after cells were exposed to oscillatory shear stress (OSS) and low shear stress, the expression of KLF2, Cav-1, and eNOS decreased and the expression of p-ERK increased. The expression of KLF2 increased gradually with the prolongation of action time, but it was still obviously lower than that of high shear stress. Following the block of Cav-1 expression by methyl β-cyclodextrin, eNOS expression decreased, and KLF2 and p-ERK expression increased. OSS may lead to endothelial cell dysfunction by Cav-1-mediated KLF2/eNOS/ERK signaling pathway.

X-ray irradiation offers a promising avenue to expedite the green synthesis of nanoparticles with high efficiency, simplicity, and environmental friendliness. X-ray technologies, such as X-ray photoelectron spectroscopy (XPS), X-ray absorption fine structure (XAFS), and synchrotron X-ray technologies are utilized to explore the structural evolution of nanoparticles. We summarize numerous studies concerning X-ray-induced synthesis of gold nanoparticles. Further, we discuss the nuclear growing mechanism—radiolysis and conventional wet synthesis—explored via in situ XAFS analysis. Lastly, we propose the improvement of radiolytic synthesis and the application of in situ XAFS.

BackgroundThe fluorescence anisotropy of intercalative dye plays important roles in nucleic acid analysis, the construction of fluorescent probes, and biosensing. However, there are few studies on the fluorescence anisotropy of intercalative dyes based on framework nucleic acids (FNA).PurposeThis study aims to use DNA tetrahedrons (TDN) as scaffold to build the fluorescence anisotropy probes of SYBR Green I, DAPI and DiYO-1.MethodsA series of TDN fluorescence anisotropy probes were constructed by precisely regulating the size of DNA tetrahedrons through DNA sequence design, characterizing DNA nanostructures by using synchrotron radiation small angle X-ray scattering (SAXS). The influence of TDN size on fluorescence anisotropy of SYBR Green I, DAPI and DiYO-1 was investigated by experiments.ResultsThe results show that the fluorescence anisotropy of probes increased with the increase of TDN size of SYBR Green I and DAPI, separately. For TDN/DiYO-1 probes, the fluorescence anisotropy decreases with the increase of TDN size as the edge length of TDN is between 7~20 bp, however, the fluorescence anisotropy increases as the edge length of TDN is bigger than 20 bp. After the dye interacted with the tetrahedron, the structure of DiYO-1 changes, resulting in the decrease of fluorescence anisotropy.ConclusionsTherefore, the fluorescence anisotropy of intercalators could be tuned by controlling the TDN size precisely. The fluorescence anisotropy probes based on FNA is expected to be an excellent probe.

Absrtact Aiming at the safety problem of the hydraulic keyless sleeve coupling caused by the increase of bearing power of a ship’s CPP,studied the interference installation of coupling sleeve-cone sleeve-tail shaft for transferring torque and thrust. Firstly,analyzed the composition and working principle of hydraulic non-key sleeve coupling,then studied the thick-wall cylinder theory of the coupling interference fit,according to the formula of the stress and deformation amount at a certain diameter of the thick-wall cylinder,calculated the interference amount of coupling sleeve cone surface and axial displacement of coupling sleeve when transferring 2. 8 times rated torque. Then,calculated the tangential stress and synthesized the principal stress at the mean diameter of the sleeve-in conical surface at 2. 8 times of the rated torque,checked the strength of the coupling. Then,according to the stipulation that the maximum compressive stress of the cone surface was not more than 0. 7 times the yield strength,calculated the maximum cone surface interference and the maximum hoop sleeve axial displacement. Then,studied the influence of the installation and measurement error of the coupling on the transmission capacity. Then,considered the interference loss caused by surface roughness,selected the design values of interference and axial displacement within the allowable range of the code. Finally,studied the technical of the interference fit of the coupling. The results show that the design interference value and hoop sleeve axial displacement meets the ship inspection regulation of transferring 2. 8 times rated torque,and the cone surface compressive stress does not exceed 0. 7 times yield strength of the material,which meet the application requirements,and the research results and installation technology can be used for reference by peers.

There is abnormal fluid pressure widely distributed in Yinggehai-Qiongdongnan Basin, with abnormal zones extending from different depths, and the formation causes of abnormal pressure here are complicated. It is one of the three HTHP offshore regions in the world at present. Hence, drilling in this region is very difficult. It is discovered in drilling practices in recent years that, due to the multiple formation mechanisms of abnormal formation pressure in this region, the conventional pressure prediction model based on under-compaction theory is insufficient to explain the abnormal high pressure suddenly occurring in the middle shallow layer in diapiric structure of Yinggehai-Qiongdongnan Basin, which causes very large deviation of pore pressure prediction before drilling. Based on the basic principle of improved Fillippone method and with the three-dimensional high precision seismic velocity field of geologic modeling inversion, the authors build a three dimensional pore pressure model of target block, extract the pressure slice of horizon and across the target well, analyze the other source pressure transmission possibly caused by formation connectivity, and import them into the mathematical model of pore pressure prediction, so as to attain the purpose of improving the precision of pore pressure prediction. This method has been well applied in pre-drilling pressure prediction for the HTHP block in the South China Sea, reaching a prediction precisi on above 95%.

The contrast between the disruption of genome topology after cohesin loss and the lack of downstream gene expression changes instigates intense debates regarding the structure-function relationship between genome and gene regulation. Here, by analyzing transcriptome and chromatin accessibility at the single-cell level, we discover that, instead of dictating population-wide gene expression levels, cohesin supplies a general function to neutralize stochastic coexpression tendencies of cis-linked genes in single cells. Notably, cohesin loss induces widespread gene coactivation and chromatin co-opening tens of million bases apart in cis. Spatial genome and protein imaging reveals that cohesin prevents gene co-bursting along the chromosome and blocks spatial mixing of transcriptional hubs. Single-molecule imaging shows that cohesin confines the exploration of diverse enhancer and core promoter binding transcriptional regulators. Together, these results support that cohesin arranges nuclear topology to control gene coexpression in single cells.

Objective To investigate the chemoresistance of human triple-negative breast cancer(TNBC) MDA-MB-468 cells induced by adriamycin(ADM) and the underlying mechanism. Methods MDA-MB-468 cells were treated with ADM at different concentrations for 24h, then MTT assay was used to detect the inhibitory rate of cell growth and the sensitivity of MDA-MB-468 cells to ADM. Immunofluorescence staining was used to detect the expression level of ABCG2 and Western blot was used to test the expression levels of phosphorylated Stat3(p-Stat3), cMyc and ABCG2. Results The sensitivity of MDA-MB-468/ADM to ADM was remarkably reduced and the expression of drug resistance protein ABCG2 was increased obviously in MDA-MB-468/ADM cells. In addition, the expressions of p-Stat3, cMyc and ABCG2 were much higher in MDA-MB-468/ADM cells than those in MDA-MB-468 cells. Interestingly, when the phosphorylation of Stat3 was inhibited by WP1066, the expressions of cMyc and ABCG2 were downregulated; furthermore, the sensitivity of MDA-MB-468/ADM cells to ADM was increased (P < 0.05). Conclusion ADM could induce the chemoresistance of human TNBC MDA-MB-468 cells through Stat3-cMyc signal pathway.

BackgroundHuman brain tissue is usually obtained by donating, and post-mortem delay (PMD) is one of the important factors affecting Golgi staining in human brain. However, currently there are relatively few studies on how PMD affects Golgi staining in human brain tissue.PurposeThis study aims to explore the changes in the morphology and structure of pyramidal neurons in the cerebral cortex of mice with PMD.MethodThe changes of human brain PMD were simulated by using mouse brain tissues placed in vitro for different times, and light microscope imaging data were obtained by Golgi staining and Nissl staining. At the same time, the synchrotron X-ray micro-CT imaging technology was used to realize neurons three-dimensional imaging visualization. The Sholl analysis was employed to study the Golgi-stained pyramidal neurons in the cerebral cortex.ResultsAnalysis results show that the completeness and complexity emerge a significant decreasing trend with the increase of PMD, and the statistical results of dendritic spines also show the same decrease trend. The three-dimensional neuron visualization results reconstructed by synchrotron radiation X-ray micro-CT technology confirm the above analysis results.ConclusionsThis study provides a research foundation for the establishment of Golgi staining method of human brain tissue and synchrotron radiation X-ray imaging.

In order to achieve home intelligence, this paper introduces an interactive system of intelligent cloud home based on CC3200 Wi-Fi microcontroller unit(MCU), WeChat official account and Ali cloud server. Users can not only control household equipment by WeChat official account remotely，but also get the status of sensors. The paper provides an overall design scheme and introduces the hardware component of system. It also gives the software design of CC3200 MCU, WeChat official account and Ali cloud server. Experiments results show that the proposed system runs steadily, has better user experiences，and has high application value.

Based on the ANSYS finite element software,the method of dividing the contact area of the four point contact ball bearing is proposed. Establish a uniform thin four point contact ball bearing 1/2 single rolling and ring and the bearing finite element model. Calculation and analysis of the grid cell size on contact characteristics of four point contact ball bearing accuracy influence and solve the bearing finite element model in the static radial force load distribution rules and obtained the thin-walled four point contact ball bearing,the more precise the elliptic contact area shape and four point connected contact state. Research shows that: for the calculation of the contact characteristics and the size of mesh generation approximate to 50 percent of the semi minor axis of the contact ellipse can get more precise results,for thin walled four point contact ball bearings,ball and the inner and outer rolling contact should force,the equivalent force and contact deformation and radial load is nonlinear ascending relationship,contact force and load distribution of the calculated results with the Hertz contact theory should be calculated values are in good agreement. The calculation results are more accurate to simulate the contact characteristics and load distribution of the thin wall four point contact ball bearing.

The bi-directional DC / DC converter in DC microgrid is a typical nonlinear system which has large voltage disturbance during lead accumulator charging and discharging. In order to solve the problem of voltage disturbance, the linearization of the converter is realized by exact feedback linearization, and the sliding mode controller is designed by using exponential approximation law. The simulation results show that the method has fast response speed, strong anti-interference ability and good steady-state characteristics.

Animal studies show aging varies between individuals as well as between organs within an individual1-4, but whether this is true in humans and its effect on age-related diseases is unknown. We utilized levels of human blood plasma proteins originating from specific organs to measure organ-specific aging differences in living individuals. Using machine learning models, we analysed aging in 11 major organs and estimated organ age reproducibly in five independent cohorts encompassing 5,676 adults across the human lifespan. We discovered nearly 20% of the population show strongly accelerated age in one organ and 1.7% are multi-organ agers. Accelerated organ aging confers 20-50% higher mortality risk, and organ-specific diseases relate to faster aging of those organs. We find individuals with accelerated heart aging have a 250% increased heart failure risk and accelerated brain and vascular aging predict Alzheimers disease (AD) progression independently from and as strongly as plasma pTau-181 (ref. 5), the current best blood-based biomarker for AD. Our models link vascular calcification, extracellular matrix alterations and synaptic protein shedding to early cognitive decline. We introduce a simple and interpretable method to study organ aging using plasma proteomics data, predicting diseases and aging effects.

In order to reduce the amount of high energy consumption materials such as cement in filling, save resources, and fully recycle industrial waste. In this paper, Changxing coal mine as the research background, through data analysis, and through the test configuration based on red mud iron tailings, mixed with desulfurization gypsum, lime, cement, activator of new cementitious materials. And through the test analysis, the best proportion of coagulant admixture is determined as follows: red mud iron tailings dosage 6, cement sand ratio 1:3, mass concentration 68%.

The dynamics equation of the four gears parallel drive system of shield machine cutter is established.The 3D model of the four gears parallel drive system is established by using the UG software.The dynamic process of the four gears parallel drive system is simulated by using the ADAMS software.Then the influence of meshing damping,meshing stiffness,backlash and distribution of driving gear on the load sharing are also analyzed.The research shows that the larger the difference between meshing stiffness and meshing damping is,the more uneven the load sharing is,when the driving load changes,backlash has a larger effect on the load balance,the different distributions of driving gear have rather a great impact on the stability of driven system.The results can provide theoretical basis for the design and manufacture of the four gears parallel drive system.

Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG) have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC). Two kinds of chimeric human antibodies (chimeric #7 and #17) were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.