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[Objective] To explore the effectiveness of the Revised Universal Soil Loss Equation (RUSLE) model in simulating soil erosion on slope surfaces during vegetation restoration in the Loess Plateau. [Methods] This study utilized rainfall-runoff and sediment data from ten runoff plots in Ansai Fangta small watershed in northern Shaanxi Province during 2016—2022. Utilizing various commonly used algorithms for RUSLE model factors specific to the Loess Plateau, a total of 144 combinations of factors were simulated to estimate soil erosion on restored slopes. The Nash-Sutcliffe efficiency coefficient (NSE) and root mean square error (RMSE) were used to evaluate the effectiveness of the model simulations. [Results] The results indicated that the simulated soil erosion on restored slopes using the 144 factor combinations ranged from -38.47 to 0.19 for NSE and from 1.92 to 12.65 t/(hm2·a) for RMSE, suggesting limited model performance. The selected algorithms for RUSLE model factors appeared to be inadequate for assessing soil erosion on slopes undergoing vegetation restoration. Further improvements are needed for the individual factors within the RUSLE model. When applying RUSLE model to simulate soil erosion on restored slopes in the Loess Plateau, it is recommended to utilize data with high temporal resolution to reduce errors in calculating the R-factor, and comprehensively consider the effects of soil physical and chemical properties such as soil organic matter content, soil particle size and aggregate structure and bulk density on K-factor, and the the effects of vegetation coverage, vegetation height, litter, and biological crust and C-factor, full consider to slopes steeper than 10° in refining the LS-factor. [Conclusion] The RUSLE model is not well-suited for simulating soil erosion in the context of vegetation restoration on abandoned slopes in the Loess Plateau.This study provides some reference for the research and development of soil erosion model and the application of RUSLE model on the slope of vegetation restoration in the Loess Plateau.

Built environments have complex effects on the public's physical and mental health. Revealing the mechanisms and pathways through which the urban built environment influences public health can provide a basis for optimizing built environments. This helps avoid issues, such as environmental pollution, lack of social interaction, and insufficient physical activity, ultimately contributing to the enhancement of public health. Western academia has a more established foundation for research, whereas domestic endeavors are currently in the exploratory phase. A comparative analysis of relevant domestic and international studies can help elucidate the developmental trajectory of research in this field, identify common issues and characteristics, and guide the direction for advancing domestic research. Therefore, based on the Web of Science and China National Knowledge Infrastructure databases, this study systematically reviewed 658 English and Chinese studies published from 2000 to 2022 in the fields of urban and rural planning, geographic sciences, health medicine, and environmental psychology, focusing on the impact of the built environment on public health. Utilizing "Citespace" software, this study conducted a quantitative analysis and systematic review of the theoretical framework, study topics, and emerging trends in the research. The findings revealed disparities between Western and Chinese academies in terms of theoretical innovation, study groups, and research content. Specifically, international studies have pioneered theoretical perspectives, such as social welfare and environmental justice. Guided by these theories, researchers have explored the mechanisms through which the built environment affects public health in diverse population groups. Although domestic studies exhibit a relative lack of theoretical innovation, their primary focus has been the introduction and empirical application of Western theories in the Chinese context. These studies often concentrate on the transmission paths of the impacts on the older and women groups through static empirical evidence, lacking dynamism in their approaches. Furthermore, drawing upon the previously stated theoretical underpinnings, methodological approach, and research content, this paper summarized the analytical framework of "Built Environment Elements, Mediated Impacts, and Public Health." It meticulously examined the differential effects of three spatial elements—green space, land use, and road traffic—on public health. This study provides a detailed analysis of the mechanisms involved, highlighting the ecological and psychological benefits arising from exposure to and interactions with green spaces. It also analyzes how judiciously designed and compact land use patterns shape travel preferences, reduce travel distances, mitigate reliance on motor vehicles, and enhance the frequency of individual activities. Furthermore, the study outlines the ramifications for optimizing the road network system and transitioning travel modes to ameliorate traffic pollution, alleviate traffic pressure, and mitigate pedestrian injuries, among other variables. The purpose of this study was to systematically comprehend the current status and disparities in domestic and international research concerning the impact of the built environment on public health and to explore a series of health issues triggered by the built environment from the perspective of urban planning, with the hope of promoting health geography in China, offering guidance for future academic directions, and prompting local management authorities to formulate precision policies addressing public health challenges.

Carbon emission reduction in the construction industry is crucial for promoting low-carbon transformation of the industry and for realizing the carbon peaking and carbon neutrality goals. This study analyzes the current status of carbon emissions in Chinese construction industry. It identifies that the production of building materials and the operation of buildings are the primary sources of carbon emissions in the overall construction process. Moreover, the growth rate of carbon emissions from the construction industry in China is decelerating, and the spatial characteristics of carbon emissions demonstrate an increase from the south to the north and from the west to the east. We have identified six key challenges that must be addressed to achieve carbon peaking and carbon neutrality in the construction industry of China: policy and standards framework, energy-efficient and carbon-reducing technologies, reduction of carbon emissions from existing buildings, carbon emission data collection and monitoring systems, economic incentives, and increased awareness of carbon reduction. Staged goals for the low-carbon development of the construction industry are also proposed. Furthermore, we suggest improving related policies and standards system, optimizing the use of energy-saving technologies, reducing carbon emissions in existing buildings, developing green finance, improving the ability to monitor carbon emissions, and enhancing the awareness of energy conservation and carbon reduction, so as to provide references for the low-carbon transformation and high-quality development of China’s construction industry.

The occurrence of salt rock in China is generally featured with multiple interlayers and thin salt layers, which has many restrictions on the single vertical well method for solution mining. For this reason, a small-spacing dual well solution mining method was proposed to overcome the adverse geological conditions. It is essentially a dual well direct-flow brine displacement method making use of the large-sized solution mining casing to offer fast solution mining rate, short storage construction duration and high utilization rate of salt layer. Specifically, the physical model experiments, under different dual-well spacing and cavity communication modes, were conducted to explore the influence of well spacing on the final shape of cavity. The results show a small horizontal length of cavity, as a result of small well spacing, hinders the full use of the horizontal space. Whereas a larger well spacing can significantly slow down the dissolution of the cavity in the horizontal section, and further result in the irregular cavity shape. Evidently the solution mining method based on precast butted wells can provide a higher cavity-forming rate. In practical dual well solution mining projects, the dual-well spacing should be determined according to the geological conditions and engineering requirements. The research results are expected to provide reference and guidance for the cavity shape design and process parameter optimization of solution mining for small-spacing dual well in salt cavern gas storages.

Background From previous studies, the frequency of administration of recombinant human erythropoietin injection (rHuEPO) has no association with its therapeutic effect in renal anemia in chronic kidney disease (CKD), and there is no significant difference in the efficacy between weekly single dosing and divided dosing. Most hemodialysis patients are clinically treated with moderate-dose rHuEPO, but there is a lack of research on the safety of single and divided administration of moderate-dose rHuEPO. Objective To compare the safety between weekly single and divided administration of moderate-dose rHuEPO for renal anemia in maintenance hemodialysis patients. Methods This study was designed as a randomized, parallel-group controlled, non-inferiority clinical trial. Eighty-eight patients with renal anemia who underwent maintenance hemodialysis at the Hemodialysis Room, Tongzhou Branch, Dongzhimen Hospital, Beijing University of Chinese Medicine from January 2019 to May 2021 were selected and randomly divided into an experimental group and a control group with 44 in each. For comparing the safety and efficacy of weekly single and divided administration of moderate-dose rHuEPO, 29 cases (experimental subgroup 1) and other 15 cases (experimental subgroup 2) in the experimental group received an rHuEPO dose of 6 000 U, and an rHuEPO dose of 4 000 U, once a week, respectively; 30 cases (control subgroup 1) in the control group received a single rHuEPO dose of 2 000 U, three times a week (6 000 U per week in total), and other 14 cases (control subgroup 2) received a single rHuEPO dose of 2 000 U, twice a week (4 000 U per week in total) . Results Safety analysis: two-factor repeated-measures ANOVA showed that the type of intervention scheme and duration had no interaction effects on systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pre-dialysis serum potassium between experimental subgroup 1 and control subgroup 1, and between experimental subgroup 2 and control subgroup 2 (P>0.05), and produced no main effects on systolic blood pressure, diastolic blood pressure, mean arterial pressure, and pre-dialysis serum potassium in experimental subgroup 1 and control subgroup 1, and between experimental subgroup 2 and control subgroup 2 (P>0.05). The serum levels of AST, ALT and TBiL were similar between experimental subgroup 1 and control subgroup 1 at baseline and 12 weeks of treatment (P>0.05). Likewise, they were similar between experimental subgroup 2 and control subgroup 2 at baseline and 12 weeks of treatment (P>0.05). No thromboembolic, cardiovascular or cerebrovascular events and gastrointestinal reactions related to rHuEPO occurred in any of the subgroups during the 12-week treatment. Efficacy analysis: the hemoglobin level (reference range was 110-130 g/L) in experimental subgroup 1 〔65.5% (19/29) 〕was similar to that in control subgroup 1 〔73.3% (22/30) 〕at 12 weeks of treatment (χ2=0.425, P=0.514). The serum levels of hemoglobin were similar between experimental subgroup 2 and control subgroup 2 at 12 weeks of treatment (P>0.05). The levels of red blood cell count, hematocrit, percentage and absolute number of reticulocytes, ferritin and transferrin saturation did not vary between experimental subgroup 1 and control subgroup 1, and between experimental subgroup 2 and control subgroup 2 either at baseline or 12 weeks of treatment (P>0.05) . Conclusion Weekly single and divided administration of moderate-dose erythropoietin had no significant difference in medication safety in the treatment of renal anemia in maintenance hemodialysis patients.

Dissimilar material structure has the advantages of both cost and performance, and has become an important means of lightweight for the new generation of autobody closure panels. However, the difference between physical properties of sheets and the complex change of adhesive material properties are easy to lead to structural curing mismatch deformation. In order to eliminate the structure deformation, a method for deformation prediction and surface reconstruction pre-compensation was proposed. Then, considering the material property transformation effect of curing degree, chemical shrinkage, and stress relaxation, a thermal-chemical-structural field coupled model for high temperature curing of hemming adhesive was established. Taking the typical aluminum/steel sheet curved-edge hemming structure as the research object, the multi-physics field curing process was simulated and analyzed, and the deformation of aluminum alloy outer panel was predicted, which was verified by non-contact measurement experiment using digital image correlation (DIC) method. Finally, the geometric compensation of curing deformation was conducted, the compensation efficiency of constraint direction, connection direction, and normal direction was compared and analyzed, and the reliability of the method was verified by experiment. The results show that compared with the traditional viscoelastic model, the multi-physics field coupling model can more accurately reflect the high temperature curing deformation of hemming structures with dissimilar materials. The geometric compensation method based on non-uniform rational B-splines (NURBS) surface reconstruction can effectively reduce the curing deformation of structures, and the normal direction compensation method is more efficient. This paper provides an important reference for the improvement of manufacturing accuracy and process optimization of the new generation of autobody closure panels with dissimilar materials.

In order to solve the problem of strong ground pressure behavior of fully mechanized top-coal caving face under the influence of hard roof and concentrated coal pillar, the design principle of directional long borehole subsection hydraulic fracturing is analyzed, and the fracturing design scheme considering the influence of “square” of the working face is proposed, which is applied in 42202 fully mechanized top-coal caving face of Shendong Buertai Coal Mine. The results show that after the directional long borehole staged hydraulic fracturing technology is implemented in the “square” range of the working face, the incoming pressure intensity and incoming pressure step distance in the fracturing area of 42202 working face decrease significantly, and the incoming pressure step distance decreases by 4.3%. When the pressure is applied, the average resistance of the support is reduced by 6.9%, the dynamic load coefficient is reduced by 4.2%, the coal wall of the working face is basically free of obvious caving, and the collapse of the goaf at the tail of the machine is sufficient. The approach of two sides of the auxiliary transportation chute in 42202 working face is reduced by 30.0%, and the approach of the top and bottom plate is reduced by 24.2%; the maximum stress of the auxiliary side is reduced by 32.1%, and the stability of the surrounding rock along the auxiliary transportationchannel is improved as a whole. After fracturing, the stress of anchor cable is greatly reduced and the stress of anchor bolt fluctuates violently. It is proved that the directional long borehole staged fracturing technology can effectively solve the far-field overburden structure of the working face, make the overlying basic roof collapse orderly and form a stable “voussoir beam structure”, and ensure the “gangue of gob-hydraulic support-coal wall of the working face” stability. The results can provide experience and basis for rock stratum control under similar mining conditions.

In the roll-hemming forming process of door cover, the non-metallic flanging adhesive and the interaction between light metal and flanging adhesive will affect the manufacturing accuracy and performance of the door cover, and increase the difficulty of roll-hemming forming and quality control of automobile body sheet with adhesive. Therefore, a numerical analysis model for roll-hemming forming of aluminum alloy sheet with adhesive was proposed based on the finite element method and the smooth particle hydrodynamic (FEM-SPH) method. First, SPH was used to simulate the extrusion flow process of the flanging adhesive, and a roll-hemming simulation model of sheet metal with adhesive was established in combination with FEM. Then, an experimental platform for two-pass roll-hemming forming of aluminum alloy sheet with adhesive was built, and the roll-hemming loss and surface wave coefficient were taken as the roll-hemming forming quality index to analysis and verify the validity of the numerical model. After that, the quality change between the first pass and the last pass and the key process parameters affecting quality were studied based on the orthogonal test method. Finally, the fitting relationship between roll-hemming forming quality and process parameters was established. The results show that the roll-hemming loss and the surface wave coefficient of the last pass are reduced compared with the first pass. The process parameters that affect the surface wave coefficient in descending order are flanging height, fillet radius, TCP-RTP value, and roller diameter. The process parameters that affect the roll-hemming loss in descending order are TCP-RTP value, fillet radius, flanging height, and roller diameter. The fitting relationship can support the prediction of roll-hemming forming quality of aluminum alloy sheet with adhesive.

The filling rate of adhesive is defined based on the geometric dimensions of the hemming model, and the numerical simulation model of the hemming process with adhesive is established by using the finite element method-smoothed particle hydrodynamics (FEM-SPH) method. By comparing and verifying with the hemming experiment with adhesive, the quantitative study of the influences of the hemming adhesive diameter, the edge distance, and the hemming thickness on the filling rate is realized. The research results show that the flow state and the final filling state of the adhesive layer obtained in the experiment are similar to the numerical simulation results, and the filling rate of the adhesive layer obtained in the experiment is highly consistent with the numerical simulation result, which verifies the feasibility and accuracy of the numerical simulation model. Further analysis shows that the influences of the hemming adhesive diameter, the edge distance, and the hemming thickness on the filling rate decrease in order, and the relationship formulas between the filling rate and process parameters, such as the hemming adhesive diameter, the edge distance, and the hemming thickness, are obtained by fitting, which provides a basis for the optimization design of the hemming process with adhesive of the automobile body sheet.

Ti45Al-8Nb-0.3Y-mCo (m=0, 0.5, 1, 2, atom fraction/%) alloys were prepared by vacuum arc non-consumable melting method. The microstructure and high temperature oxidation resistance of the alloys were investigated. The results show that the microstructure of TiAl-Nb alloy can be significantly refined by addition of Co element. However, Co can remarkably inhibit the formation of α2+γ lamellar while promote the formation of Co-rich B2 precipitations in the alloys. The oxide films formed on the Ti45Al-8Nb-0.3Y-mCo alloys mainly consist of relatively loose TiO2 and Al2O3 mixtures, after oxidation at 1000 ℃ for 100 h in air. With the increase of Co content, the mass gains of the TiAl-Nb-0.3Y alloys after oxidation increase obviously, while much better anti-spalling performance of the oxide films can be obtained. Addition of Co can reduce the internal stress of the oxide film to a certain extent, which is beneficial to the anti-spalling performance of the oxide film. However, the coarse B2 precipitation caused by Co weakens high temperature oxidation resistance of the alloy.

Objective To construct a 5-fluorouracil (5-FU)-resistant colon cancer cell line, and to investigate the role of stearoyl CoA desaturase 1 (SCD1) in the resistance of colon cancer cells to 5-FU. Methods Drug resistance to 5-FU was induced in colon cancer cell line HCT116 by increasing the concentration intermittently and repeated inducing and screening with high concentration to produce drug-resistant cell line HCT116/5FU. The survival rates and half maximal inhibitory concentration (IC50) were measured by CCK-8 assay in HCT116, HCT116/5FU, HCT116-Control and HCT116-OE-SCD1 cells after the treatment of 5-FU. Immunohistochemical assay was employed to measure the expression of SCD1 after the fabrication of colon cancer and paracancerous tissue chips. Quantitative PCR and Western blotting were applied to detect the expression of SCD1. CCK-8 assay, plate clone formation and crystal violet staining were used to detect cell survival status. The apoptotic rates were detected by AnnexinV-FITC/PI double staining. HCT116-Control and HCT116-OE-SCD1 subcutaneous xenograft models in nude mice were established to observe the effect of SCD1 on tumor growth. Western blotting was carried out to detect the expression of apoptosis-related proteins. Results The IC50 value of 5-FU was 0.90±0.06 μg/mL in HCT116 cells, and 15.02±0.81 μg/mL in HCT116/5FU cells, with a multiple of resistance about 16.7 times. The expression of SCD1 was higher in drug resistant colon cancer tissues than in common colon cancer tissues and corresponding paracancerous tissues. And its expression level was also higher in HCT116/5FU cells than HCT116 cells. Overexpression of SCD1 reduced the apoptotic rate of colon cancer cells(P < 0.01). Xenograft nude mouse model indicated that SCD1 overexpression enhanced the resistance of colon cancer cells to 5-FU. After 48 h of 5-FU treatment, the expression of bcl-2 and caspase3 were lower in HCT116-OE-SCD1 group than HCT116-Control group(P < 0.01). Conclusion The 5-FU-resistant model of colon cancer HCT116/5FU cells is successfully established. SCD1 promotes the resistance to 5-FU in colon cancer cells

To improve the performance of adjusting performance for wall-press oil and gas in-pipe robot,part of the in-pipe robot adjusting mechanism is parametric modeled and optimization designed through ADAMS. The integrated adjusting mechanism model is set up by Solid Works according to the optimized data and the structure characteristics of adjusting mechanism for in-pipe robot,then imports the model and makes simulation analysis in ADAMS. The optimized nut horizontal thrust is reduced 41. 5%,besides,the impact load which acts on adjusting mechanism of in-pipe robot is simulated,the influence of the horizontal thrust and changes in the situation of compression spring when the adjusting mechanism is in the process of adjusting or suffering impact load is separately obtained,the theoretical basis for the selection of suitable motor and the compression spring is provided.

Electronic nose and tongue technology and a combination of both techniques with manual sensory evaluation were used for wine sample testing to identify different types of honeysuckle wines. The obtained data were analyzed using principal component analysis (PCA) and discriminant factor analysis (DFA) of both odor and taste. The sum of the contributions of the first principal component (PC1) and second principal component (PC2) of the PCA for different varieties of honeysuckle wine using the electronic nose, tongue, and a combination of the two was 90.97%, 90.91%, and 95.00%, respectively. According to DFA of the electronic nose, the total contribution was 89.72%, which corroborated the results of PCA. The Xiaoqu brewed honeysuckle wine was fresher than the Daqu brewed and Daqu formulated honeysuckle wines, consistent with the results obtained using the artificial senses. Therefore, electronic nose and tongue technology can accurately identify different types of honeysuckle wine samples and can be used to analyze them. [ABSTRACT FROM AUTHOR]

In order to overcome the hidden security troubles in the IPC control system of filtered cigarette maker in the absence of internal protection measures, the security holes and attacked routes of the IPC control system were analyzed and three security monitoring modules were designed by means of developing a typical attack chain model for the control system. The first module was designed for the security monitoring of pseudo instruction of the system network. The second module was designed for the non-intrusive security monitoring of the IPC controller, and the third module was designed for monitoring the abnormal control behavior of the control network. Thereby, an A3MA (Acquisition-Monitoring-Monitoring-Monitoring-Alarm) security monitoring model, which covered the IPC core controller and core communication network of the cigarette maker was configured by integrating with disturbance-free data acquisition and security risk early-warning. The security monitoring model was tested on an IPC control system in a ZJ17E cigarette maker, the results showed that the A3MA security monitoring model could rapidly discern the behaviors of pseudo-control instructions in the system network, rapidly locate the unauthorized tampering behaviors targeting IPC controller and rapidly identify the abnormal control behaviors of EtherCAT control network. This model provides a technical support for the multi-layer security monitoring of IPC control system in filtered cigarette maker. [ABSTRACT FROM AUTHOR]

In order to solve the problem of missed detection easily caused in dense multi-target detection ' an infrared small target detection algorithm based on double neighborhood contrast measure was proposed. First ' the peak search algorithm was used to screen out the candidate targets; then the candidate targets were traversed through a single-scale three-layer double neighborhood window; finally the dual-neighbor contrast model was used to calculate the minimum gray contrast of the candidate target area ' and the contrast and suppresses clutter were enhanced by the diagonal gradient. The results show that compared with the five comparison methods ' the background suppression factor and contrast gain of this method are increased by 4.7 times and 1.8 times on average ' respectively ' which effectively suppresses clutter and enhances the target. This research can accurately detect multiple targets that are close to each other ' which is helpful to improve the accuracy of multi-target detection in complex backgrounds. [ABSTRACT FROM AUTHOR]

The "type" of diamond had been developed and trended to perfect in last century. The spectral classification depends on ultraviolet visible near infrared spectrum (UV-Vis-NIR) and mid-infrared spectrum (MIR), mainly relates to nitrogen and boron impurity element. The structure models of nitrogen and boron in each type of diamond have tended to be more plausibility, but an enormous number of lattice defects even related to nitrogen are huge challenge for future work to reach a better understanding. This is an impenetrable wall on the way to explore new application areas for diamond. This article compiles some absorption characteristics in the spectra ranged from ultraviolet, visible light to infrared region. Especially the diamond classification system has been summarized completely. Furthermore, some absorbing features detected in the ultraviolet-visible and infrared spectral lines (UV-Vis-MIR) have been come up with a plausible explanation and/or established somewhat more reasonable structure models. It is very referential collecting these spectral characteristics and their corresponding theoretical models for further research and apply diamond materials. [ABSTRACT FROM AUTHOR]

In order to improve the effective utilization of features in remote sensing image scene classification and achieve the purpose of improving the accuracy of remote sensing image classification, a remote sensing image classification method based on dual-channel depth-dense feature fusion was used for theoretical analysis and experimental verification. First, the image convolution layer features and fully connected layer features was separated extracted by constructing a composite dense convolutional network model. In order to exploit the deep information of the image, the deep convolutional layer features extracted by the model were recombined and encoded by the bag of visual words to capture the deep local features of the image. Finally the linear and weighted methods were used to fuse local and global features and then classify them. The results show that using the datasets UC Merced Land-Use and NWPU-RESISC45 for experiments, the classification accuracy obtained is 93.81% and 92.62%, respectively. This method makes full use of the complementarity of local features and global features to achieve the full expression of deep image information. [ABSTRACT FROM AUTHOR]

Objective To understand the results and influencing factors of SARS-CoV-2 nucleic acid detection among specimens in different types and stages of coronavirus disease 2019 (COVID-19) progression. Methods The samples of deep-tussive sputum, pharyngeal swab, stool and conjunctival swab were collected among the suspected cases and close contacts of COVID-19 in Guilin. The SARS-CoV-2 RNAs were detected using double fluorescence real-time RT-PCR. The epidemiology, clinical diagnosis and laboratory data were collected to analyze the factors of improving the sensitivity of nucleic acid detection. Results A total of 654 samples were collected among 537 suspected cases and close contacts, including 569 deep-tussive sputum, 26 pharyngeal swabs, 28 stool and 31 conjunctival swabs. Thirty-two SARS-CoV-2 nucleic acid positive cases were found, with a nucleic acid positive rate of 6.00% (32/537). The median days (range) of the first nucleic acid positive deep-tussive sputum sampling time from onset day of illness were 0-23 days. The SARS-CoV-2 nucleic acid positive rate of deep-tussive sputum was significantly higher than that of pharyngeal swabs (P=0.000). The SARS-CoV-2 nucleic acid positive number of stool and conjunctival swabs were 19 cases and 5 cases, respectively, which their sampling time were the average 7 days later than that of the first sampling deep-tussive sputum with SARS-CoV-2 positive. Among the 32 confirmed cases of COVID-19, there were 28 cases collected a single sample of deep-tussive sputum with SARS-CoV-2 nucleic acid positive, which samples of 6 cases, 6 cases, 3 cases, 4 cases and 9 cases were collected on the first day, 2nd day, 3rd day, 4th day, 5th day and above, respectively. In 4 cases, samples of deep-tussive sputum should be collected twice or more before nucleic acid positive results. Before sampling, one case had a history of fever and treatment. As a close contact, two samples of deep-tussive sputum were collected on the 21st day and 23rd day from onset day of illness, with SARS-CoV-2 nucleic acid negative and positive, respectively. Conclusions The deep-tussive sputum is better than pharyngeal swab in the detection of SARS-CoV-2 nucleic acid, and the SARS-CoV-2 nucleic acid positive can also be detected by stool and conjunctival swab. The sampling type, sampling time and treatment history are the influencing factors of the sensitivity of SARS-CoV-2 nucleic acid detection. So as not to miss detection, suspected cases or close contacts should be isolated observation and multiple sampling detection. [ABSTRACT FROM AUTHOR]

A finite element model of electromagnetic blanking forming processes with field shape was established based on LS-DYNA R8.0 software for diaphragms used in carrier rocket n aerospace field, and the variation rules of current, magnetic field, and sheet stress states under the field shape case were revealed. Furthermore, the processing parameters of the discharge voltage and the billet diameter were optimized. The results show that the section quality is optimized and the shear deformation is intensified with using the field shape. The sheets present a tearing fracture mode under the forming processes. With the increase of the discharge voltages, the deformation degree of the sheets increases, the fillet area of the fracture decreases and the diameter of the blanking part decreases firstly increases. With the increase of the billet diameters, the deformation degree of the sheets increases firstly and then decreases, the fillet area of the fracture decreases firstly and then increases, and the diameter of the blanking part increases and then and then decreases. The optimum values of the discharges voltages and the billet diameters are as 12 kV and 130 mm respectively. [ABSTRACT FROM AUTHOR]

The main purpose is test and optimization of process parameters of spinning process in the production of high count wool products. Using Minitab software and Tian - Qou method, experimental design and comparison on the Spinning section' technological parameters and on high count wool products, the two continuous data are analyzed by using the line end index and the slub index, in which the fine end index and the slub index are required for the smaller the better. According to the test results, through the statistics analysis and comparison, for obtaining a more reasonable span yarn process parameter of various parts is suitable for spinning high count wool products, to improve the high count wool product quality and production efficiency through the spinning process parameters optimization of high count wool products. [ABSTRACT FROM AUTHOR]

Objective: To create a novel chitosan antibacterial hemostatic sponge (NCAHS) and to evaluate its material and biological properties., Methods: Chitosan, a polysaccharide, was used as the sponge substrate and different proportions of sodium tripolyphosphate (STPP), glycerol, and phenol sulfonyl ethylamine were added to prepare the sponges through the freeze-drying method. The whole-blood coagulation index (BCI) was used as the screening criterion to determine the optimal concentrations of chitosan and the other additives and the hemostatic sponges were prepared accordingly. Zein/calcium carbonate (Zein/CaCO 3 ) composite microspheres loaded with ciprofloxacin hydrochloride were prepared and added to the hemostatic sponges to obtain NCAHS. Scanning electron microscope was used to observe the microscopic morphology and porosity of the NCAHS. The water absorption rate, in vitro antibacterial susceptibility rate against Staphylococcus aureus ( S. aureus ) and Escherichia coli ( E. coli ), in vitro coagulation performance, and hemocompatibility of NCAHS were examined. The coagulation performance of NCAHS was evaluated by using rabbit liver injury and rabbit auricular artery hemorrhageear models and commercial hemostatic sponge (CHS) was used as a control. The in vivo biocompatibility, including such aspects as cytotoxicity, skin irritation in animals, and acute in vivo toxicity, of the NCAHS extracts was examined by using as a reference the national standards for biological evaluation of medical devices., Results: The NCAHS prepared with 1.5% chitosan ( W / V ), 0.01% STPP ( W / V ), 0% glycerol ( V / V ), 0.15% phenol-sulfonyl-ethylamine ( V / V ), Zein and CaCO 3 at the mixing ratio of 5∶1 ( W / W ), Zein at the final mass concentration of 2.5 g/L, and ethanol at the final concentration of 17.5% ( V / V ) were fine and homogeneous, possessing a honeycomb-like porous structure with a pore size of about 200 μm. The NCAHS thus prepared had the lowest BCI value. The water absorption ([2362.16±201.15] % vs. [1102.56±91.79]%) and in vitro coagulation performance (31.338% vs. 1.591%) of NCAHS were significantly better than those of CHS ( P <0.01). Tests with the in vivo auricular artery hemorrhage model ([36.00±13.42] s vs. [80.00±17.32] s) and rabbit liver bleeding model ([30.00±0] s vs. [70.00±17.32] s) showed that the hemostasis time of NCAHS was significantly shorter than that of CHS ( P <0.01). NCAHS had significant inhibitory ability against S. aureus and E. coli . In addition, NCAHS showed good in vitro and in vivo biocompatibility., Conclusion: NCAHS is a composite sponge that shows excellent antimicrobial properties, hemostatic effect, and biocompatibility. Therefore, its extensive application in clinical settings is warranted., Competing Interests: 利益冲突　所有作者均声明不存在利益冲突, (© 2024《四川大学学报（医学版）》编辑部 版权所有Copyright ©2024 Editorial Board of Journal of Sichuan University (Medical Sciences).)

COVID-19 represents the most serious public health event in the past few decades of the 21 st century. The development of vaccines, neutralizing antibodies, and small molecule chemical agents have effectively prevented the rapid spread of COVID-19. However, the continued emergence of SARS-CoV-2 variants have weakened the efficiency of these vaccines and antibodies, which brought new challenges for searching novel anti-SARS-CoV-2 drugs and methods. In the process of SARS-CoV-2 infection, the virus firstly attaches to heparan sulphate on the cell surface of respiratory tract, then specifically binds to hACE2. The S protein of SARS-CoV-2 is a highly glycosylated protein, and glycosylation is also important for the binding of hACE2 to S protein. Furthermore, the S protein is recognized by a series of lectin receptors in host cells. These finding implies that glycosylation plays important roles in the invasion and infection of SARS-CoV-2. Based on the glycosylation pattern and glycan recognition mechanisms of SARS-CoV-2, it is possible to develop glycan inhibitors against COVID-19. Recent studies have shown that sulfated polysaccharides originated from marine sources, heparin and some other glycans display anti-SARS-CoV-2 activity. This review summarized the function of glycosylation of SARS-CoV-2, discoveries of glycan inhibitors and the underpinning molecular mechanisms, which will provide guidelines to develop glycan-based new drugs against SARS-CoV-2.

For cochlear implant training and robotic cochlear implant experiments, the design method of scalable scala tympani model was proposed. The mathematical model of the cochlea was used as the central curve of scala tympani channel. Referring to the clinical anatomy data, the contour of the scala tympani cross-section was approximated as an ellipse. The profile was placed along the central curve, and the angle was adjusted to determine the position and orientation of the profile in three dimensions such that the central curve passes through its center. The data was imported into Matlab to generate a three-dimensional mathematical model of scala tympani, which can be expanded by setting different scale factors. The virtual scala tympani model was generated in SolidWorks, and the 2:1 fully transparent scala tympani model were fabricated by 3D printing to replace the specimen for experiment.

Objective: To investigate the effect of bilateral superior cervical sympathetic ganglion occlusion (SCG) on aortic dissection and its possible mechanism., Methods: Forty-five SD rats were randomly divided into three groups with 15 in each:blank control group, sham operation group and SCG group. β-aminopropione (666 mg·kg -1 ·d -1 ) was given by subcutaneous injection for 4 weeks to establish the aortic dissection model. Rats in SCG group were given SCG before the injection of β-aminopropione. Blood pressure and heart rate of the rats were monitored using noninvasive tail artery blood pressure measuring instrument; sympathetic activity was monitored using drug block method; the structure of aortic wall was observed using HE staining; collagen fibers in aortic wall was observed using Sirius red staining; protein expression of Apelin was detected by immunohistochemistry; and the protein expression of matrix metalloproteinase (MMP)-2, 9 was detected by Western blotting., Results: During the experiment, the body mass of the sham operation group and SCG group was smaller than that of the blank control group (all P <0.05), and the body mass of the SCG group was larger than that of the sham operation group (all P <0.05). The heart rate and sympathetic activity of the sham operation group were higher than those of the blank control group (all P <0.05), while the SCG group were lower (all P <0.05). Compared with the blank control group, the aortic wall in the sham operation group was thickening, while that in the SCG group was improved. A large number of collagen-1 in the aortic wall of the blank control group was stained brown by Sirius red, which was lighter in SCG group, and the staining in the sham operation group was the lightest. Compared with the blank control group, the expression of Apelin, MMP-2 and MMP-9 protein in the sham operation group increased (all P <0.05), while those in the SCG group decreased (all P <0.05)., Conclusions: SCG can effectively reduce the incidence and mortality of aortic dissection in rats, which may be related to the inhibition of sympathetic activity and the decrease of collagen-1, Apelin, MMP-2 and MMP-9 expression.

Objective To investigate the effect of diabetes mellitus on lymphocytes in rheumatic heart valve tissue and its mechanism. Methods Valve tissues of 40 patients undergoing heart valve replacement were collected, including 20 patients in rheumatic heart disease group (without diabetes) and 20 patients in diabetic group (rheumatic heart disease combined with diabetes). In addition, 20 cases of valve tissue from control group were collected. HE staining was used to observe the damage of valve tissue and the area of collagen degeneration. CD4 + T cells, CD8 + T cells, B cells and plasma cells were detected by immunohistochemical staining. Flow cytometry was used to detect the proportion of regulatory T cells (Tregs) in peripheral blood. Results Compared with the rheumatic heart disease group, the damage of valve tissue in the diabetic group was further aggravated, the number of infiltrating inflammatory cells increased, and the area of collagen degeneration was enlarged. Compared with the control group, the number of T cells, CD4 + T cells, CD8 + T cells, B cells and plasma cells in valve tissue of patients with rheumatic heart disease increased significantly. Diabetes mellitus further increased the number of T cells, CD4 + T cells, B cells and plasma cells in valve tissue, but had no significant effect on CD8 + T cells. The proportion of Tregs in the peripheral blood of patients with rheumatic heart disease was significantly reduced. Diabetes mellitus could further reduce the proportion of Tregs. Conclusion The number of T cells, CD4 + T cells, B cells and plasma cells in heart valves of rheumatic heart disease patients with diabetes mellitus go up significantly, and Treg ratio goes down.

Objective: To explore the effectiveness of functional reconstruction of hand grasp and pinch by tendon transfers in patients with cervical spinal cord injury., Methods: Between July 2013 and January 2016, tendon transfer surgery were performed in 21 patients (41 hands) with cervical spinal injury that motion level was located at C 6 to reconstruct hand grasp and pinch function. There were 18 males and 3 females with a mean age of 42.3 years (range, 17-65 years). Nineteen patients were with complete spinal cord injury [American Spinal Injury Association (ASIA) grading A], 1 patient was with central cord syndrome whose bilateral hands were completely paralyzed and lower limbs were normal (ASIA grading D), and 1 patient was with cervical spondylotic myelopathy (AISA grading D). The time from injury to hospitalization was 12-22 months (mean, 16.8 months). According to the International classification of surgery of the hand in tetraplegia (ICSHT), there were 6 cases of grade O3, 10 of grade O4, 3 of grade OCu5, and 2 of grade O5. The surgery was divided into two stages with an interval of 6-11 months. At the first stage, grip function was reconstructed in all patients by transfering the extensor carpi radialis longus from radialis side to palmar side through subcutaneous tunnel, and braided and sutured with the flexor pollicis longus and flexor digitorum profundus. At the second stage, the lateral pinch function of the thumb and index finger was reconstructed by braiding and suturing the radial half of the extensor carpi ulnaris (the patients graded as ICSHT O3) or pronator tere (the patients graded above ICSHT O3) with extensor pollicis longus and abductor pollicis longus. The grasp force, the thumb and index finger lateral pinch force, and the maximum fingertips distance between the thumb and index finger were measured at preoperation and at different time points after operation. The modified Lamb and Chan questionnaire, based upon the activities of daily living, was used to evaluate the hand function of all patients at 6 months after sencond stage surgery., Results: There was 1 patient with elbow skin lesion, 1 patient with wrist stiffness; both of them recovered after corresponding treatment. All the 21 patients were followed up 15-32 months (mean, 19.6 months) without wound infection, tendon adhesion, tendon rupture, and other complications. The grasp forces of all patients were significantly improved at 4 weeks, 3 months, 6 months, and 1 year after the first stage surgery when compared with preoperative value ( P <0.05); and no significant difference was found between different time points after operation ( P >0.05). The thumb and index finger lateral pinch force and the maximum fingertips distance between the thumb and index finger of all patients were also significantly improved at 4 weeks, 3 months, 6 months, and 1 year after the second stage surgery when compared with preoperative values ( P <0.05); and no significant difference was found between different time points after operation ( P >0.05). And there was no significant difference of above indexes between the patients graded as ICSHT O3 and above ICSHT O3 ( P >0.05). The functional outcome was good in 19 cases, fair in 1 case, and poor in 1 case according to modified Lamb and Chan questionnaire at 6 months after second stage surgery., Conclusion: Tendon transfer can significantly improve the hand function and the quality of life of the patients with complete cervical spinal cord injury.

Minimally invasive surgery (MIS) has the advantages of small trauma, quick recovery and lower risk of the surgery. Compared with the traditional two-dimension laparoscopic technique, three-dimension laparoscopic system uses the double beam imaging system as well as the three-dimensional imaging display device so as to compensate for the lack of depth information in two-dimension laparoscopic imaging technique, reduce the surgeon's difficulty in using surgical instruments and enhance the accuracy of the surgery. For those reasons, the author designed a glassesfree three dimensional wide-field electronic laparoscopic system, which consists of dual CMOS camera module, image processing module and glasses-free display module that can offer depth information. The active shape model is applied to eye tracking, for the purpose of getting the wide-field to help doctor obtain 3D display in more places. Primary experimental results of the simulation using the system show that operators with the aid of proposed system spend less time finishing the task than those using traditional system without depth perception during operation.

Endo-cellulases are important to efficiently hydrolyze cellulose, and widely used in biotechnology. In this study, we overexpressed and characterized an endo-cellulase from Aspergillus nidulans. This endo-cellulase was successfully overexpressed in flasks and fermentor, and its concentration in fermentor reached 0.89 mg/mL. The optimal pH and temperature of the were 4.0 and 80 ℃ respectively, and it was very stable between pH 2.0 and 12.0. It was thermally stable below 60 ℃, whereas it was inactivated very quickly above 70 ℃. Its CMCase activity could be enhanced by Co²⁺, Mn²⁺ and Fe²⁺, whereas it was inhibited by Pb²⁺, Ni²⁺ and Cu²⁺. Therefore, this endo-cellulase exhibited good pH stability and thermostability below 60 ℃, and has the potential as commercial enzymes.

Objective: To conduct the preliminary positioning and qualitative research of high-frequency ultrasonic imaging at Ashi points (including tender points and trigger points) in neck-type cervical spondylosis and explore the relevant law so as to provide the evidence for the selection of acupuncture scheme., Methods: Thirty patients in compliance with the diagnostic criteria of neck-type cervical spondylosis were selected. The trigger points, tender points and placebo points were positioned on any of the three available oriented lines. The point-to-point high-frequency real-time dynamic ultrasonic imaging technology was used to scan and position each point and record the changes in ultrasound gradation anatomy and two-dimensional ultrasound in perimysium, two-dimensional and color Doppler ultrasonography and blood flow. The ultrasound characteristics were analyzed., Results: ①Regarding the changes in ultrasound gradation anatomy and two-dimensional ultrasound in perimysium, the anatomic gradation at trigger points and tender points was in the sequence as cutaneous layer, subcutaneous fat layer, shallow muscular tissue layer, deep muscular tissue layer and vertebrae. The linear high echo presented in cutaneous layer; the low echo in subcutaneous fat layer; the linear high echo in muscular fasciae; the low echo in muscular layer and the clear linear echo in its perimysium; the high echo and declined posterior echo in vertebrae. Compared with the placebo points, 93.3% of trigger points (28/30) presented enhanced or thickened perimysium echo ( P <0.05), and 96.7% of tender points (29/30) presented enhanced or thickened perimysium echo ( P <0.05). The differences were not significant between the trigger points and the tender points ( P >0.05). ②In the two-dimensional ultrasonography, the clear linear echo presented in perimysium, the enhanced or thickened echo in perimysium of trigger points and tender points. In the color Doppler ultrasonography, the blinking unstable dotted blood flow signal or stable short rod-like blood flow signal presented in the trigger points and tender points. ③Regarding the condition of blood flow, 56.7% of trigger points (17/30) presented Ⅱ degree of color blood flow signal and 83.3% of tender points (25/30) presented Ⅱ degree of color blood flow signal; 0% of placebo points presented Ⅱ degree of color blood flow signal. Compared with the placebo points, the differences in the rate of Ⅱ degree of color blood flow signal were significant statistically at both the trigger points and the tender points (both P <0.05). The difference was not significant between the trigger points and tender points ( P >0.05)., Conclusions: In the high-frequency ultrasound imaging at trigger points and tender points in neck-type cervical spondylosis, the ultrasound imaging characteristics present, which are similar between the trigger points and the tender points. The high-frequency ultrasound imaging is valuable in positioning and quantitative research of Ashi points in cervical spondylosis and has a certain significance to guide treatment.

Objective: To investigate the effects of the first neuron connection for the reconstruction of lower extremity function of complete spinal cord injury rats., Methods: Forty adult female Sprague Dawley rats of 300-350 g in weight were selected to prepare the models of L₁ transverse spinal cord injury. After 2 weeks of establishing model, the rats were randomly divided into control group (n = 20) and experimental group (n = 20). In the experimental group, the right hind limb function was reconstructed directly by the first neuron; in the control group, the other treatments were the same to the experimental group except that the distal tibial nerve and the proximal femoral nerve were not sutured. The recovery of motor function of lower extremity was observed by the Basso-Beattie-Bresnahan (BBB) scoring system on bilateral hind limbs at 7, 30, 50, and 70 days after operation. The changes of the spinal cord were observed by HE staining, neurofilament 200 immunohistochemistry staining, and the technique of horseradish peroxidase (HRP) tracing., Results: After establishing models, 6 rats died. The right hind limb had no obvious recovery of the motor function, with the BBB score of 0 in 2 groups; the left hind limb motor function was recovered in different degrees, and there was no significant difference in BBB score between 2 groups (P > 0.05). In the experimental group, HE staining showed that the spinal cord was reconstructed with the sciatic nerve, which was embedded in the spinal cord, and the sciatic nerve membrane was clearly identified, and there was no obvious atrophy in the connecting part of the spinal cord. In the experimental group, the expression of nerve fiber was stained with immunohistochemistry, and the axons of the spinal cord were positively by stained and the peripheral nerve was connected with the spinal cord. HRP labelled synapses were detected by HRP retrograde tracing in the experimental group, while there was no HRP labelled synapse in the control group., Conclusion: Direct reconstruction of the first neurons is sufficient in the regeneration of corresponding neural circuit by the growth of residual axon; but the motor function recovery of the target muscles innervated by peripheral nerve is not observed.

Objective: To find a potential link among ABO blood group, lipid profiles and coronary artery disease (CAD) and to estimate the effect size of connection using mediation analysis model., Methods: A total of 898 consecutive patients undergoing coronary angiography were enrolled, and divided into CAD group and non-CAD group according to angiographic findings. According to ABO blood group, patients were divided into O blood group and non-O blood group, as well as A blood group and non-A blood group. Baseline characteristics among various groups were compared and the association of ABO blood group, CAD and lipid profile was explored., Results: Subjects of blood type A had higher concentration of total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) compared with that of non-A type (TC: (4.43 ± 1.12) mmol/L vs. (4.18 ± 1.09) mmol/L, LDL-C: (2.79 ± 0.99) mmo/L vs. (2.59 ± 1.01) mmol/L, all P < 0.01). TC and LDL-C were significantly higher while high density lipoprotein cholesterol (HDL-C) and ApoA I levels were significantly lower in CAD group than in non-CAD group (TC: (4.36 ± 1.05) mmol/L vs. (4.13 ± 1.16) mmol/L, LDL-C: (2.61 ± 0.87) mmol/L vs. (2.47 ± 0.94) mmol/L; ApoA I: (1.38 ± 0.29) mmol/L vs. (1.45 ± 0.33) mmol/L; all P < 0.01). After adjustment for traditional cardiovascular risk factors, blood group A and TC remained significantly associated with the risk of CAD (OR = 1.88, 95% CI 1.280-2.774, P < 0.01; OR = 1.03, 95% CI 1.018-1.033, P < 0.01, respectively). Specially, mediation analysis indicated that 10.5% of the effect of A blood group on CAD was mediated by TC levels (P < 0.01)., Conclusion: Our data indicate that there is an association between ABO blood group, TC levels and risk of CAD. Around 10.5% of the effect of A blood group on CAD is mediated by TC levels.

To evaluate the fatigue behavior of nitinol stents, we used the finite element method to simulate the manufacture processes of nitinol stents, including expanding, annealing, crimping, and releasing procedure in applications of the clinical treatments. Meanwhile, we also studied the effect of the crown area dimension of stent on strain distribution. We then applied a fatigue diagram to investigate the fatigue characteristics of nitinol stents. The results showed that the maximum strain of all three stent structures, which had different crown area dimensions under vessel loads, located at the transition area between the crown and the strut, but comparable deformation appeared at the inner side of the crown area center. The cause, of these results was that the difference of the area moment of inertia determined by the crown dimension induced the difference of strain distribution in stent structure. Moreover, it can be drawn from the fatigue diagrams that the fatigue performance got the best result when the crown area dimension equaled to the intermediate value. The above results proved that the fatigue property of nitinol stent had a close relationship with the dimension of stent crown area, but there was no positive correlation.

Objective: To explore the efficacy of a novel tissue engineered bone in repairing bone defects using poly-lactic acid-polycaprolactone (PLA-PCL) scaffolding seeded with PEG-bone morphogenetic protein-2 (BMP-2) transfected rBMSCs (rabbit bone marrow stromal cells)., Methods: rBMSCs were harvested, transfected with PEG/BMP-2 or liposome/BMP-2 and then implanted into PLA-PCL tissue engineered bone. The protein level of BMP-2 was assessed by Western blot and immunohistochemistry. Enzyme-linked immunosorbent assay (ELISA) was employed to measure the amount of BMP-2 in culture media. The mRNA levels of BMP-2 and osteocalcin were assayed quantitatively by real-time polymerase chain reaction (PCR). The middle portion of bilateral radius in New Zealand rabbits was excised and implanted with tissue engineered bone. And the modified areas were monitored by radiology, hematoxylin-eosin staining and immunohistochemical staining of BMP-2., Results: PEG-BMP-2 nanoparticles (NPs) and BMP-2 loaded PEG-PLA-PCL tissue engineered bones were successfully constructed. The novel PEG-PLA-PCL NPs/DNA complex was superior for transfecting BMP-2 in rBMSCs compared to traditional liposomes. Moreover, the mRNA level of osteocalcin and alkaline phosphatase activity also increased after a transfection of BMP-2 encapsulated NPs., Conclusion: PEG-PLA-PCL NPs/BMP-2 complex facilitates bone repair so that it provides theoretic rationales for potential clinical treatments.

Objective: To understand the current situation and characteristics of commercial sexual behavior among old male clients in Guangxi, and to explore the associated risk factors of HIV infection., Methods: The areas in Guangxi where more old male HIV cases were reported followed by survey on those male clients who were over 60 years of age, were selected. A total of 5 ml blood sample was collected to test antibodies of HIV and syphilis. Risk factors were calculated by the multivariate logistic analysis method., Results: A total of 1 236 questionnaires were completed in the survey. 65.61% of the old male clients were from low-grade venues with 53.64% of them never using a condom when engaging in commercial sex behavior. 47.33% of them patronized sex workers for around 10 years. 53.32% of them patronized prostitutes not less than 2 times in the last 30 days. Thirty subjects were HIV positive (2.43%) and 40 were syphilis positive (3.24%). Factor as 'having fixed partners' (OR = 0.302, 95% CI:0.140-0.650) appeared protective for the old male clients of HIV infection, with a history of patronizing sex workers from 1 to 5 years (OR = 2.552, 95% CI: 1.086-5.998). Frequency of patronizing sex workers not less than 4 times in the last 30 days (OR = 3.002, 95%CI:1.047-8.607) seemed the high risk factor of HIV infection., Conclusion: Older-aged male clients showed high HIV and syphilis infection rates in Guangxi, and most of them were using the low-grade venues. Commercial sexual behaviors in the areas would include early and, frequent exposure, but with poor protections. High risk factors of HIV infection might relate to "no fixed sexual partners" and "frequently commercial sexual behavior".

Objective: To investigate the synergistic effect of oleanolic acid (OA) and cyclosporine A (CsA) on the survival of renal allografts in rats., Methods: Renal allograft transplantation was performed using BN rats as donors and LEW rats as recipients. Forty male LEW rats were randomized into 4 equal groups for interventions with DMSO-PBS (control), OA, CsA, or CsA+OA, starting from 1 day before transplantation. Serum creatinine levels were regularly examined, and the survival of rats were recorded. On day 5 after transplantation, CD4(+) and CD8(+) T-cell infiltration in the renal grafts was analyzed by immunohistochemistry; the concentrations of the proinflammatory cytokines (IL-1β, IFN-γ, IL-2, IL-4, and IL-17), anti-inflammatory cytokine IL-10 and chemokines (IP-10, MCP-1, MIP, and Mig) were analyzed with Luminex; the T-cell phenotypes (IFN-γ, IL-10, IL-4, and IL-17) were analyzed using ELISpot., Results: In OA+CsA group, renal allograft survival was markedly prolonged and CD4(+) and CD8(+) T cell infiltration in the graft significantly decreased as compared to other groups. A significant decrease in IL-2 was observed in OA group and OA+CsA group, especially the latter. Compared with the control group, all the 3 treated groups showed significantly decreased IL-1β, IP-10 and MCP-1, increased IL-10 levels, decreased percentages of T cells secreting IFN-γ, IL-4 and IL-17, and increased percentage of T cells secreting IL-10. The increments of serum IL-10 level and T cell percentage were more prominent in OA+CsA group than in the other two intervention groups., Conclusions: OA and CsA synergistically ameliorate renal graft rejection and inflammation and promote allograft survival and function in rats.

Objective: To examine the feasibility of RNA pooling technique in the diagnosis on acute HIV infection among female sex workers (FSWs) working at the low-grade venues., Methods: Plasma samples from the low-grade-venue FSWs in Guangxi, in 2011 were tested for HIV antibody using the rapid testing method. All samples which were HIV antibody negative in the rapid testing were tested for HIV RNA with RNA pooling technique. FSWs who showed HIV RNA positive were tested for HIV antibody by Western blot method in 3 months. The HIV incidence in the low-grade venue FSWs was counted under the estimation formula., Results: There were 6 469 cases of FSWs who were recruited in this study. Through rapid testing, results showed that HIV antibody was positive in 139 cases, with the positive rate as 2.15%. 6 330 FSWs with HIV antibody negative were tested by HIV RNA pooling method, with 7 of them showing HIV RNA positive, in which 6 cases showed HIV-1 antibody seroconversion, thus were diagnosed as acute HIV infection. HIV incidence in low-grade FSWs appeared to be 1.45 per 100 person years (95%CI:1.17-1.76 per 100 person years) in Guangxi., Conclusion: Other than regular routine HIV antibody testing, it seemed necessary to adopt the HIV RNA pooling strategy in high-risk groups such as FSWs, so as to early detect the HIV infection and to timely perform the intervention or treatment programs to prevent sexual transmission of HIV.

Objective: To provide theoretical evidences for the identification and selective breeding of different major varieties of Rehmannia glutinosa by comparing their leaf characters such as the shapes, non-glandular hairs and the size and density of stomata., Method: The length, width and the ratio of the length to the width of leaves were measured, and the density and length of the non-glandular hair, the density, size and density of the stomata in the epidermis were measured by scanning electron microscope., Result: The results showed that there were obvious differences in length, width and the ratio of the length to the width of leaves, the density and length of the non-glandular hair, the density and size of the stomata in the epidermis., Conclusion: The morphological characters of the leaves mentioned above may serve as the identification standards of major varieties of R. glutinosa.

Objective: To evaluate the effect of dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) on urine superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in rats., Methods: According to 2×2 factorial analysis, 60 adult male SD rats were randomized into 10 groups (n=6), including a control group (fed with sesame oil), 3 DBP groups (fed with DBP at the doses of 30, 100 and 300 mg/kg), 3 DEHP groups (with DEHP at 50, 150, and 450 mg/kg), and 3 DBP+DEHP groups (with 30 mg/kg DBP+50 mg/kg DEHP, 100 mg/kg DBP+150 mg/kg DEHP, and 300 mg/kg DBP +450 mg/kg DEHP). The agents were administered in a single dose through gavage in a volume of 2 ml. After the treatments, the 24, 48, 72, and 96 h urine samples were collected to determine the SOD activity and MDA content., Results: DBP and DEHP, either alone or in combination, significantly decreased SOD activity and increased MDA content in the urine collected at 24 h but not at the other time points. Such changes were gradually reversed with time., Conclusion: DBP or DEHP treatment alone can result in significant oxidative damage in the kidney of rats, and the toxic effect of the combined exposure is even more obvious.

The present research was to study the biocompatibility of a composite of hydroxyapatite (HA), carbon fiber (CF) and polyetheretherket-one (PEEK) by co-culturing with the osteoblasts in vitro. Cell relative growth (RGR) was used as a quantitative assessment for cytotoxicity of the biomaterials by CCK-8. The proliferation index of the co-cultured cells and ALP activity was measured to study the effect of PEEK-HA-CF composites. Morphological properties of the osteoblast cells in vitro were observed by scanning electro-microscopy (SEM). The PEEK-HA-CF materials have no cytotoxicity to osteoblasts. The proliferation index of PEEK-HA-CF was higher than that of Ti alloy group, but these was no significant difference compared to that of control group. The ALP activity was the highest on PEEK-HA-CF composites surface after 7 days. The osteoblast cells co-cultured with the PEEK-HA-CF composite were adhered well to the biomaterial as observed under the SEM. The results suggested that the PEEK-HA-CF composites had good biocompatibility in vitro and might be a novel orthopedic implanted material.

To compare the effects between gene therapy and gradual release carrier for bone morphogenetic protein-2 (BMP-2) in repairing bone defects, bone defects for 15 mm were created.on the bilateral radius in rabbits and treated with four kinds of implantations, ie, composite of transgeneic MSCs and PLA/PCL (Group A), composite of MSCs and gradual release carrier for BMP-2 (Group B), composite of MSCs and PLA/PCL (Group C), and PLA/PCL alone (Group D). After 4, 8, and 12 weeks of the operations, X-ray, histological examination, biomechanics analysis, and bone density measurement were conducted. Results showed that both osteoblasts and mesenchymal cells displayed strongly positive expression of BMP-2 in Group A after 4 weeks of the operation, the speed and quality of bone formation in Group A were much better than those in Group B. After 12 weeks of the operations, bone defects were completely repaired in Group A. BMP-2 gene therapy is really a good method to repair segmental bone defects.

Adenovirus carrying BMP-2 gene, after being mixed with fibrinous gel, was siphoned off on biodegradable scaffolds (PLA/PCL). The composite was used to repair 1.5 cm long radius defect in rabbits. Four methods were in use in the experiments: Ad-BMP-2 plus fibrinous gel and PLA/PCL (Group A), reconstructed hBMP-2 plus fibrinous gel and PLA/PCL (Group B), Ad-Lacz plus fibrinous gel and PLA/PCL (Group C), and fibrinous gel and PLA/PCL (Group D). Results showed that the defects treated in Group A were repaired with much more new bone regenerated, bridged earlier and stronger than those in Group B 12 weeks after operation. The defects treated in the other two groups could not attain osseous tissue healing. BMP-2 gene carried by biodegradable scaffold and fibrinous gel is easy to conduct and has very strong osteoinduction ability. It is really a good method to repair segmental bone defects.