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The conventional pretreatment methods for mine water generally include coagulation, sedimentation (flotation), and filtration. However, large equipment footprint, long processing time and pollution from coagulants and flocculants have been limiting the further development of underground mine water treatment. In this light, we designed an underground mine water pretreatment device based on ultrasonic atomization for clarifying and pre-softening mine water so that the turbid mine water could be treated to meet the needs of underground production, firefighting, and dust reduction. We conducted indoor experiments on mine water clarification and pre-softening treatment using water and rock samples from the field mined-out area. The results show that: (1) This method can clarify black-gray turbid mine water with a large amount of solid impurities, effectively removing insoluble solid impurities in the water. (2) Ultrasonic atomization reduces the total hardness of the water by 72.24%. The milligram equivalent concentration of Ca2+ is reduced from 5.33 mg/L to 0.81 mg/L and the milligram equivalent concentration of Mg2+ drops from 5.23 mg/L to 2.13 mg/L, with little impact on pH. (3) The water from the mined-out area after ultrasonic atomization can meet the requirements of sprinkling in underground firefighting, spraying in dust reduction, the mining process of coal mining equipment, and the use of cooling water.

The hot deformation behavior and dynamic recrystallization of Al-11.1Zn-2.3Mg-2.0Cu-0.05Sc alloy was explored in the isothermal hot compression test with a temperature range of 653-733 K at strain rate of 10-3 s-1. The microstructural evolution of the studied alloy at different temperatures was analyzed by EBSD technology. The dynamic recrystallization（DRX） critical strain， critical stress， fraction， and average grain size equations were established by linear regression. The results show that the fitted equations can accurately describe the DRX characteristics of the studied alloy during hot deformation.The increase in the deformation temperature enlarges the misorientation angle inside the grains， which facilitates the DRX progress. The distributions of crystal orientation tend to be more homogeneous with the increase in temperatures. Moreover， dynamic recovery is the dominant dynamic softening mechanism. With the temperature change， there are three types of recrystallization mechanisms in the microstructure of aluminum alloy， including discontinuous dynamic recrystallization， continuous dynamic recrystallization， and geometric dynamic recrystallization.

Background Medical work is characterized as challenging, tasking and stressful. The effort-reward imbalance (ERI) model suggests that if the organizational environment contributes to ERI, it can negatively affect employees. The investigation of medical staff is an important part of the 6th National Health Services Survey in 2018. The good job satisfaction and work conditions of medical staff are important determinants of service utilization and health improvement for the population. The sense of accomplishment and satisfaction of medical staff is also an important goal of the new healthcare reform. Objective To explore the relationship between ERI and job stress, and provide a reference for reducing the job stress of medical staff. Methods The data for this study were obtained from the results of a sample survey of 4 156 healthcare workers in Beijing during the 6th National Health Services Statistics Survey in 2018. A predictive structural equation model of job stress was constructed and based on ERI questionnaire and job stress questionnaire. Relevant parameters were estimated by using the partial least squares to analyze the relationship between ERI and job stress. Results The valid records for participating in the ERI index calculation were 4 098. According to the ERI index calculation results, 1 333 (32.53%) healthcare workers were in a state of balance between effort and reward, and 2 765 (67.47%) health workers were in a state of imbalance between effort and reward. The results of factor analysis showed that 46.00% of the job stress experienced by medical staff in Beijing can be attributed to ERI model. Extrinsic, intrinsic effort and work reward all had a direct impact on job stress (P

Objective With the rapid increase in construction projects in the western regions in recent years, the impact of seasonal freeze-thaw cycles in the high-altitude areas of western China has become more pronounced. Conducting research on the microscopic characteristics and strength degradation properties of rocks under freeze-thaw cycles is crucial for guiding engineering construction in these cold, high-altitude regions. Methods To study the influence of freeze-thaw cycles on rock structure and mechanical properties, we collected diorite samples from a tunnel in the Kangding area and examined the effects of freeze-thaw cycles on their microstructure and mechanical characteristics. Firstly, thin rock sections were observed under a polarizing microscope to obtain mineral compositions and microstructures. Then, CT scanning technology was used to scan the granite samples after freeze-thaw cycles, and the scanned layers were binarized using threshold segmentation. The scanning images of different layers were binarized using threshold segmentation, and high-resolution 3D data and images of the internal and external structures of the samples were obtained by stacking the binary image layers. Fractal theory was applied to calculate the box-counting dimension of the images and quantitatively assess their complexity. This analysis allowed us to examine the evolution and distribution characteristics of the internal structure of granite under freeze-thaw cycles. Results Under a polarizing microscope, the rock exhibits a block-like structure with a patchy, coarse-grained, and unequal-grained granite texture, with locally visible metasomatic worm structures. The main phenocryst minerals are alkaline feldspar. Other minerals range in size from 0.25 to 4.0 mm and primarily include quartz, plagioclase, and alkaline feldspar. Secondary minerals include biotite and epidote, while accessory minerals comprise apatite, zircon, and pyrite. Microscopically, the rock is identified as porphyritic, coarse-grained, and unequal-grained biotite diorite granite. Freeze-thaw cycles were applied to the granite samples in the laboratory to study the strength evolution and explore the relationship between structural evolution and strength. The results indicate that the freeze-thaw cycle effect leads to an overall increase in the internal porosity of the granite's microstructure, though the rock's permeability changes minimally, with an increase of only 0.003×10−3 μm2. The internal pore development is uneven, primarily due to the emergence of new micropores, causing changes in the overall structure of the sample. After freeze-thaw cycles, the complexity of the internal structure of the rock decreases, but the overall integrity remains good, with the fractal dimension staying at a high level. Fractal analysis shows that 20 freeze-thaw cycles do not cause significant changes in the structural complexity of granite. However, the overall mechanical properties of the sample decline, viscosity increases, and long-term strength shows significant attenuation, raising the strain threshold for entering the creep test stage. Conclusion When evaluating the safety of rocks with dense primary structures, considering only their structure may lead to deviations from the actual situation. It is essential to combine necessary strength indicators for a comprehensive evaluation. After undergoing freeze-thaw cycles, rocks tend to exhibit more significant deformation while maintaining lower strength. Therefore, appropriate treatments are required for construction in high-altitude areas. [ Significance ] This study provides a reference for applying fractal theory to the evolution of rock microstructure and the relationship between rock microstructure and strength evolution. It also offers valuable guidance for engineering construction in high-altitude and cold regions.

The existing intelligent optimization algorithm of air volume of mine ventilation network has the defects of complex model, slow convergence speed, easy falling into local optimum when solving the air adjustment parameters. There is a lack of research on the combination of optimal selection of air adjustment branches. To solve the above problems, an intelligent control method of air volume of mine ventilation network based on improved beetle antennae search (BAS) algorithm is proposed. Firstly, the mathematical model of air volume optimal adjustment is established by taking the air volume demand of the air consumption branch as the optimization objective. In view of the air volume adjustment constraint conditions in the model, the non-differentiable exact penalty function and the simulated annealing algorithm are adopted to optimize the penalty term, so that the model is unconstrained. Secondly, by solving the sensitivity matrix and combining the theory of air volume sensitivity and branch dominance, the optimal adjustment branch set is selected. The air resistance adjustment range is determined as the initial solution set of the model. Finally, based on the improved BAS algorithm, the optimal air adjustment parameters are solved. The corresponding air adjustment facilities are controlled to realize air volume adjustment. The reliability of the method is verified by experiments based on the mine ventilation experimental platform. The results show that compared with the standard BAS algorithm and particle swarm optimization (PSO) algorithm, the improved BAS algorithm has superior comprehensive optimization performance. The average value and optimal solution of air volume are higher than those of the PSO algorithm and standard BAS algorithm. Although the average running time is slightly longer than the standard BAS algorithm, it is far shorter than the PSO algorithm. The average convergence algebra is the most, the precision is the highest, and it is easy to jump out of the local loop to get the optimal solution. After setting the air volume adjustment target, the intelligent control method of air volume of the mine ventilation network based on the improved BAS algorithm can quickly and accurately solve the optimal value of the air volume of the branch to be adjusted. The adjusted branch air volume meets the air volume adjustment requirements of mine safety production, and the air volume is increased up to 46.5%.

ObjectiveTo analyze the effectiveness and safety of clinical use of different types of stem cells to provide evidence for governmental supervision of key issues in clinical utilization of stem cells.MethodsSix literature databases in China and abroad were searched for relevant literature published from January 2010 to July 2020， and a systematic review was conducted.ResultsThe study showed 72 studies concerning the effectiveness and safety of different types of stem cells in clinical utilization. Although clinical utilization of stem cells had some therapeutic effects for certain diseases， their long-term effect and safety need to be further evaluated， especially their potential risk of tumorigenicity.ConclusionTo protect the patients’ interest， physicians should fully weigh the benefits against the risks of clinical utilization of stem cells， and relevant governmental departments should strengthen supervision of ethics of clinical research and therapies involving stem cells as well as supervision of stem cell products.

In the paper， national and international ethical requirements and supervision on stem cell research and clinical application were analyzed after literature review. It is suggested that the development of stem cell technology should be timely tracked， prospective ethical research related to stem cells should be enhanced， and that stem cell research and clinical translation should comply with relevant international ethical guidelines and national regulations in China. In addition， it is indicated that the oversight of stem cell products and their clinical use will be continuously improved in our country.

Aiming at the shortcomings of the current coal mine explosion venting devices, a new explosion venting door is designed, and its structure, explosion venting mechanism and beneficial efficiency enhancement are discussed. FLUENT software was used to simulate gas explosion under different working conditions and the change laws of explosion pressure, flame temperature and flame speed were analyzed by monitoring, and the explosion venting effect of the explosion vent door was verified. The results show that when the gas mass fraction is 9.5%, it is found that the explosion pressure peak generated by the explosion-proof wall is the largest, and the pressure is maintained at 0.29 MPa after attenuation, and the surrounding rock and equipment in the roadway are continuously damaged under high-pressure environment. The explosion venting door can quickly release the pressure, so that the fire area can be closed without fresh air, and reduce the occurrence of secondary explosions and secondary disasters. Under the working condition of gas mass fraction 5.5%-11.5%, the overall change law of gas explosion characteristic parameters is the same. As the gas volume fraction increases, the gas explosion characteristic parameters first increase and then decrease. The explosion venting capacity of the explosion venting door has nothing to do with the gas volume fraction, however the gas volume fraction changes, the pressure is released and the fire area is closed at the same time.

Most of the existing mine ventilation system health evaluation methods use constant weights. The evaluation results easily deviate from the actual situation and cannot reflect the real state of the system. At the same time, there are many indexes selected, and the weight of each index is low, which makes it difficult to detect the impact of some indexes abnormalities on the overall health of the system. Based on the actual operating conditions and health evaluation requirements of mine ventilation system, 21 influencing factors are selected as the health evaluation indexes to construct the health evaluation index system of mine ventilation system. Fuzzy comprehensive evaluation, analytic hierarchy process and variable weight theory are used comprehensively to carry out the health evaluation of mine ventilation system. The analytic hierarchy process is used to determine the weights of evaluation indexes, the Hardarmard product variable weight model based on membership degree is used to calculate the index weights. The maximum membership degree criterion of fuzzy comprehensive evaluation is used to determine the health degree of mine ventilation system. This method is used to evaluate the health of a coal mine ventilation system. The results show that the evaluation result of this method is consistent with the actual situation. Compared with the evaluation method based on constant weight, the weights of the evaluation index of this method can be adjusted according to the actual situation so as to make the evaluation result more objective. Moreover, this method amplifies the impact of unhealthy indexes and highlights the potential system safety hazards, which attracts the attention of relevant personnel.

To reduce the vibration damage to the riser, hydrodynamic parameters of a smooth riser and a riser with triple symmetrically distributed helical strakes are evaluated in an experiment. The wave and current in natural environment are conceptualized to the experimental condition of the oscillatory flow and the uniform flow. Experiment cases are divided into the static flow and the uniform flow, while the risers oscillate along the in-line, the transverse, and the diagonal direction. The added mass coefficient Cm and the drag coefficient Cd are calculated from experimental data by using the Morison equation. The results of the riser with strakes indicate that Cm is independent of the Keulegan-Carpenter (KC) number and the oscillating direction. Cd is found to be in inverse proportion to the ratio of 1/3 power of the KC number and the maximum flow speed to oscillatory velocity. This finding is consistent with the format of Morison parameters of a flat plate in oscillatory flow, which endows the classical theory with novel validation and implication in the design of a riser. Under the same condition, the Cd of the helical strake riser is promoted over 273% than the bare riser, which indicates that the helical strakes efficiently reduce the influence of oscillation under complex conditions. The results provide a new solution for vibration reduction of offshore structures, which is of high value in ocean engineering.

Metal additive manufacturing is a new type of material-forming technology characterized by its short process and near net shape. Equipment, material and process are critical factors which serve as the supporter, key, and foundation respectively in terms of the development of this technology. In this paper, the characteristics of the equipment, material, and process of the different representative technologies were summarized. The relations among metal additive manufacturing equipment, manufacturing material, and manufacturing process as well as their roles in the metal additive manufacturing technology were analyzed. The research status of the raw material supply system, forming system, and control system were reviewed. The typical microstructure and mechanical properties of metal additive manufacturing materials, such as titanium alloy, nickel alloy, aluminum alloy, and steel, were summarized. The effects of the manufacturing process parameters on residual stress, porosity, accuracy, and microstructure were discussed. Problems associated with the manufacturing equipment, such as high cost, limited forming size, and low forming efficiency were discussed along with the problems associated with the material, such as high production cost and poor applicability. Furthermore, problems associated with the metal additive manufacturing process, such as difficult matching of process parameters and severe thermal accumulation, were elaborated as well. Future developmental goals in metal additive manufacturing include: (a) reducing the cost of manufacturing equipment and material, (b) expanding the range of product forming size, (c) improving the product printing accuracy and forming efficiency, (d) expanding the types and application scope of metal additive manufacturing material, (e) reducing the difficulty in the matching of process parameters, (f) improving product quality and comprehensive performance, and (g) developing new types of metal additive manufacturing technologies.

Dry-wet spinning process was used to gain graphene oxide/polyimide composite fibers, then graphene/polyimide composite carbon and graphite fibers were obtained through carbonized and graphitized. Different graphene oxide contents of the composite carbon and graphite fibers were measured by thermal gravimetric analysis, Raman, mechanical properties, electrical properties,SEM and so on. The results show that when the GO content is 0.3%(mass fraction,the same below), the thermal property of the graphene oxide/polyimide composite fibers is the best. The mechanical and electrical properties are obriously improved by the addition of GO, graphitization degree also increases. When the composite carbon fibers are treated at 2800℃, GO content increases to 2.0%, the thermal conductivity of the composite graphite fibers reaches 435.57W·m-1·K-1 and cross-section structures of carbon fibers are more compact.

The paper analyzed research status and existed problems of positioning technology of sensors of supports of shearer, positioning technology based on trackage odometer and autonomous positioning technology. It put forward research content of absolute positioning technology of shear in mining coal seam by taking absolute coordinate of the mining area as reference coordinate. It discussed application of the positioning technology of shearer in automation long-wall fully mechanized coal mining face.

The traditional high utility itemsets mining algorithms cannot discover the relationships between categories at different levels of abstraction. Therefore, cross-level high utility itemsets mining algorithms have been proposed. To address the problem that the current cross-level high utility itemsets mining algorithms can only handle static data and cannot control the range of mining levels, a dynamic classification list structure DTUL is proposed to store and maintain the utility and classification information of the itemset in the window. Based on this structure, this paper proposes the first constrained cross-level high utility itemset mining algorithm based on sliding window, including the bottom-up mining algorithm CCLHM_DTU algorithm and the top-down mining algorithm CCLHM_UTD algorithm. Extensive experiments are conducted on databases containing categorical information. The experimental results show that the proposed algorithm can effectively deal with the data stream and flexibly constrain the hierarchical range of itemsets. [ABSTRACT FROM AUTHOR]

[Objective] With the rapid increase in construction projects in the western regions in recent years, the impact of seasonal freeze-thaw cycles in the high-altitude areas of western China has become more pronounced. Conducting research on the microscopic characteristics and strength degradation properties of rocks under freeze-thaw cycles is crucial for guiding engineering construction in these cold, high-altitude regions. [Methods] To study the influence of freeze-thaw cycles on rock structure and mechanical properties, we collected diorite samples from a tunnel in the Kangding area and examined the effects of freeze-thaw cycles on their microstructure and mechanical characteristics. Firstly, thin rock sections were observed under a polarizing microscope to obtain mineral compositions and microstructures. Then, CT scanning technology was used to scan the granite samples after freeze-thaw cycles, and the scanned layers were binarized using threshold segmentation. The scanning images of different layers were binarized using threshold segmentation, and highresolution 3D data and images of the internal and external structures of the samples were obtained by stacking the binary image layers. Fractal theory was applied to calculate the box-counting dimension of the images and quantitatively assess their complexity. This analysis allowed us to examine the evolution and distribution characteristics of the internal structure of granite under freeze-thaw cycles. [Results] Under a polarizing microscope' the rock exhibits a block-like structure with a patchy, coarse-grained, and unequal-grained granite texture, with locally visible metasomatic worm structures. The main phenocryst minerals are alkaline feldspar. Other minerals range in size from 0.25 to 4.0 mm and primarily include quartz, plagioclase, and alkaline feldspar. Secondary minerals include biotite and epidote, while accessory minerals comprise apatite, zircon, and pyrite. Microscopically, the rock is identified as porphyritic, coarse-grained, and unequal-grained biotite diorite granite. Freeze-thaw cycles were applied to the granite samples in the laboratory to study the strength evolution and explore the relationship between structural evolution and strength. The results indicate that the freeze-thaw cycle effect leads to an overall increase in the internal porosity of the granite's microstructure, though the rock's permeability changes minimally, with an increase of only 0.003x10-3 µm² The internal pore development is uneven, primarily due to the emergence of new micropores, causing changes in the overall structure of the sample. After freeze-thaw cycles, the complexity of the internal structure of the rock decreases, but the overall integrity remains good, with the fractal dimension staying at a high level. Fractal analysis shows that 20 freeze-thaw cycles do not cause significant changes in the structural complexity of granite. However, the overall mechanical properties of the sample decline, viscosity increases, and long-term strength shows significant attenuation, raising the strain threshold for entering the creep test stage. [Conclusion] When evaluating the safety of rocks with dense primary structures, considering only their structure may lead to deviations from the actual situation. It is essential to combine necessary strength indicators for a comprehensive evaluation. After undergoing freeze-thaw cycles, rocks tend to exhibit more significant deformation while maintaining lower strength. Therefore, appropriate treatments are required for construction in high-altitude areas. [Significance] This study provides a reference for applying fractal theory to the evolution of rock microstructure and the relationship between rock microstructure and strength evolution. It also offers valuable guidance for engineering construction in high-altitude and cold regions. [ABSTRACT FROM AUTHOR]

To address the monitoring problem in high-intensity focused ultrasound (HIFU) therapy, a new method is proposed for identification of tissue damage without the need for additional monitoring sources. The method involves studying the multi-scale fuzzy entropy (MFE) of the fundamental and second harmonic of the HIFU echo. The HIFU echo signal is denoised using spectral subtraction, and then the fundamental and second harmonic components of the signal are extracted using the kullback-leibler divergence-optimized variational mode decomposition (KLD-VMD) method. Finally, the MFE combining the fundamental and second harmonic is used to identify tissue damage. The validity of the method is verified using the equal error rate (EER), where a lower EER indicates better recognition. The study also compares the KLD-VMD method with other decomposition methods such as VMD, EMD, and ITD, in combination with MFE for tissue damage identification. The experimental results demonstrate that the tissue damage identification based on KLD-VMD and MFE achieves an EER of 5.1%, which is better compared to the other methods. Furthermore, the results also show that combining the fundamental and second harmonics improves the identification performance compared to using either echo alone. This study provides a new monitoring method for HIFU therapy with potential practical applications. [ABSTRACT FROM AUTHOR]

The reliability analysis results of complex structures based on the Kriging model were highly dependent on the fitting accuracy of the Kriging model. In the constructing processes of the Kriging model, the selection of different correlation and regression functions affected the accuracy of the model. In order to solve the impacts of model uncertainty on the reliability analysis results, while considering computational efficiency and accuracy, based on the Kriging model and Monte Carlo simulation(MCS) method, a structural reliability calculation method combining adaptive ensemble strategy and active learning function was proposed. Considering the modeling uncertainty of Kriging models, combined with multiple Kriging models, this method constructed an active learning function that comprehensively considered sample point contribution and sample point distance. The ensemble Kriging model was iteratively updated through the active learning function until the convergence conditions were satisfied. Finally the structural reliability analysis was carted out by the constructed ensemble Kriging model and MCS method. The validity of the proposed method was vetted by numerical and engineering examples, and the results show that the proposed method more robust than other major methods, and the computational efficiency higher while ensuring the computational accuracy. [ABSTRACT FROM AUTHOR]

The Upper Cretaceous Taipinglinchang Formation is the key oil-gas exploration horizon in Sunwu-Jiayin Basin. Based on the detailed field observation and description, the sedimentology of section of Taipinglinchang Formation in the east of the basin is studied in this paper. The results show that the sedimentary facies developed in Taipinglinchang Formation include lacustrine facies and fan delta facies, which can be further divided into 3 sedimentary subfacies with 6 sedimentary microfacies. The petrology and organic geochemical characteristics of the shale in Taipinglinchang Formation are analyzed by various organic geochemical testing methods. The results indicate that the mineral composition of shale is mainly quartz, belonging to felsic shale. The maceral composition is dominated by sapropelinite, with oil-prone property. The source rocks are of medium-good quality, with the organic matter types of II1-II2, which are in the low mature-mature stage, suggesting a good hydrocarbon potential. The results may provide basic data for further research and oil-gas exploration in the basin. [ABSTRACT FROM AUTHOR]

Objective To investigate the changes in expression of Toll-like receptor 3 (TLR3) and interferon-α (IFN-α) in patients with different clinical outcomes of hepatitis C virus (HCV) infection treated with direct-acting antiviral agents (DAAs), and to explore the relationship between the expression of TLR3 and IFN- α with the clinical outcomes of HCV infection. Methods A total of 149 HCV infected patients who received initial treatment were selected from Hainan General Hospital between September 2020 and August 2022. The patients were divided into two groups: chronic hepatitis C (CHC) group (n=129) and liver cirrhosis (LC) group (n=20). Additionally, 28 volunteers were selected as the control group during the same period. All patients with HCV infection were first treated with Sofosbuvir/Vipatavir tablets for 12 weeks. Blood samples were collected at 0, 4, 12, 24 and 48 weeks after treatment. Liver function indicators were detected by enzyme-linked immunosorbent assay (ELISA), while TLR3 mRNA were detected by real-time fluorescence quantitative polymerase chain reaction (qRCR), IFN-α was detected by Luminex multiplex cytokine assays. Measurement data subject to normal distribution were represented by x±s, and t test was used between groups. Compare differences between groups. Results TLR3 mRNA in CHC group was higher than that in LC group and control group at baseline (P<0.05). After 4 weeks of DAAs treatment, TLR3 mRNA in CHC and LC groups was significantly up-regulated (P<0.05). TLR3 mRNA in the CHC group was gradually downregulated to the level of the control group at 12, 24, and 48 weeks. In addition, IFN-α expression gradually increased with prolonged treatment, while it decreased in the LC group. The liver inflammation indicators in both the CHC and LC groups partially recovered after treatment with DAAs. Conclusions TLR3 is involved in viral clearance and chronic inflammatory response. The expression difference of TLR3 in patients with different clinical outcomes of HCV infection after DAAs treatment may be related to the severity of the disease. [ABSTRACT FROM AUTHOR]

In the era of big data, it is possible to carry out cooperative research on the research results of researchers through papers, patents and other data, so as to study the role of researchers, and produce results in the analysis of results. For the important problems found in the research and application of reality, this paper also proposes a research scholar interest mining algorithm based on load centrality (load centrality based interest mining algorithm for research scholars, LCBIM), which can accurately solve the problem according to the researcher's research papers and patent data. Graphs of creative algorithms in various fields of the study aggregated ideas, topic graphs are generated by aggregating neighborhoods, the generated topic information is used to construct with similar or similar topic spaces, and keywords are utilized to construct one or more topics. The regional structure of each topic can be used to closely calculate the weight of the centrality research model of the node, which can analyze the field in the complete coverage principle. The scientific research cooperation based on the load rate center proposed in this paper can effectively extract the interests of scientific research scholars from papers and corpus. [ABSTRACT FROM AUTHOR]

The oil and gas resources are abundant in the shale of the first member of Qingshankou Formation in Sanzhao Sag, Songliao Basin. To identify the distribution of shale oil sweet spots in the area and guide the deployment of parameter well, the paper studies the sweet spot prediction method based on the logging evaluation of key parameters of single well sweet spot, 3D seismic data and well-seismic combination. First, the cross plot analysis of logging data and core experimental analysis data is used to establish logging evaluation model of lithology, physical properties (porosity and permeability), oil-bearing property (saturation), organic geochemical parameters (TOC and Si), formation pore pressure and compressibility; Then the broadband constrained inversion technology is applied to predict lithology, the prestack elastic parameter inversion to predict physical properties, oil-bearing property and compressibility, and combination of constrained Dix formula inversion and model constrained wave impedance inversion technology to predict formation pressure; Finally, a set of seismic sweet spot identification technology process suitable for the shale oil of Qingshankou Formation in Songliao Basin is established to realize the double sweet spots prediction of geological and engineering sweet spots. The practice shows that the 3D seismic data can effectively predict shale sweet spots, and the actual drilling results are basically consistent with pre-drilling prediction, which proves the effectiveness of technical process. [ABSTRACT FROM AUTHOR]

The shale oil resources are abundant in the first member of Qingshankou Formation, Upper Cretaceous, in northern Songliao Basin. The previous exploration was targeted at shale fractures and interbedded thin sands and ostracod layers. Due to the limitation of distribution range of target layers, the shale oil exploration results have not been satisfactory. Focusing on the widely-developed shale reservoirs in the basin, the survey refreshes the geological understanding of shale oil in the shale reservoirs of continental basin, and forms the exploration technology system. The industrial oil flows of SYY1, SYY2 and SYY3 wells pumped after fracturing yield 3.22, 4.93 and 3.46 m³/d respectively, the flowing high-yield industrial oil run of 14.37 m³/d from SYY-1HF well and pumping oil run of 10.06 m³/d from SYY-2HF well after fracturing, achieving a major breakthrough in the strategic survey of shale oil in northern Songliao Basin. [ABSTRACT FROM AUTHOR]

Taking the shale from the first member of Qingshankou Formation in SYY-3 well of Sanzhao sag in Songliao Basin as an example, the paper studies the petrological characteristics, including sedimentary structure, organic matter abundance and mineral composition. The results show that the shale develops massive structure and laminated structure are, with TOC of 0.50%-6.82% (averagely 3.16%) and S1+S2 of 2.01x10-3-49.41x10-3 (averagely 23.02x10-3), generally belonging to good-best source rock. The mineral composition is mainly felsic mineral, followed by clay, with low content of carbonate and pyrite. Based on the petrological characteristics, the first member of Qingshankou Formation can be divided into 9 types of lithofacies by the classification criteria of organic matter abundance-sedimentary structure-mineral composition, among which the laminated felsic shale with high TOC has good hydrocarbon generation potential, serving as the most favorable lithofacies for shale oil exploration in Sanzhao sag. [ABSTRACT FROM AUTHOR]

There are abundant shale oil resources in the first member of Qingshankou Formation in Qijia and Gulong sags of Songliao Basin. In the past, the shale oil resources were calculated mainly based on incomplete old core data with corrected pyrolysis Si or chloroform asphalt A as oil-bearing parameters. The accuracy of corrected parameters was affected by multiple factors including sample freshness, testing means and correction method, leading to certain limitations in the application of the above parameters. According to the latest development in shale oil exploration, the paper compares the applications of different oil-bearing parameters (pyrolysis S1; chloroform bitumen "A" and oil saturation) in shale oil resource calculation. The result shows that oil saturation can reflect the content of free oil and dissolved hydrocarbon, without considering the influence of adsorbed oil and correction of light hydrocarbon, heavy hydrocarbon and NSO compound. This parameter is more suitable for the calculation of shale oil resources under the condition of fresh sample test data. The plane distribution of effective shale thickness, TOC, organic maturity (Ro) and burial depth are determined on the basis of latest drilling results and test data of shale oil parameter well. The shale oil enrichment areas in the first member of Qingshankou Formation in Qijiahe and Gulong sags are 1957.23 km² and 4509.09 km² respectively by multifactor overlap method. Combined with the measured data of oil saturation, density and effective porosity logging interpretation data of sealed frozen samples, the resources of shale oil enriched areas in Qijia and Gulong sags are calculated as 19.79x108 and 27.29x108 respectively, indicating the matrix shale oil in the study area has a good exploration prospect. [ABSTRACT FROM AUTHOR]

Shale oil exploration in China has entered a new field. As shale oil reservoir is much more complex than conventional reservoir, the improvement of imaging accuracy of shale oil reservoir is the key to shale oil seismic exploration. The wide-azimuth 3D seismic technique is widely used in seismic exploration currently as it can solve relatively difficult geological problems while providing high-quality seismic data. Taking the study area Y88 in Qijia-Gulong depression of Songliao Basin as an example, the paper conducts shale oil reservoir processing by wide-azimuth data, and analyzes the characteristics of wave field, signal-to-noise ratio and frequency. On this basis, the processing flow of wide-azimuth data is determined and the wide-azimuth and broadband high-resolution amplitude-preserving processing technique is adopted for better imaging. [ABSTRACT FROM AUTHOR]

The 'decoupling' between the economic development and water resources utilization in the Beijing-Tianjin-Hebei region has become an academic hot spot and research field of great concern to the administrative departments in the governments of Beijing, Tianjin and Hebei and relevant scholars. The existing literature mainly uses the classic framework of decoupling discrimination, focusing on the total amount of water resources utilization in the Beijing-Tianjin-Hebei region, or short-term decoupling situation evaluation and decoupling effect of industrial water resources utilization in the Beijing-Tianjin-Hebei region. Few scholars have emphasized the guiding role of dual control action in the evaluation mode of decoupling, took the decoupling relationship between the economic development and industrial water resources utilization of different plan periods in the Beijing-Tianjin-Hebei region as a whole consideration, and revealed the internal driving mechanism of water resources utilization decoupling in the Beijing-Tianjin-Hebei region. Therefore, based on the analysis perspective of driving force-pressure-response, this study constructs the evaluation mode of decoupling between economic development and water resources utilization in the Beijing-Tianjin-Hebei region under dual control action. The Tapio elastic coefficient method is used to dynamically compare and evaluate the decoupling situation of economic development and water resources utilization in the Beijing-Tianjin-Hebei region and its industries in different planning periods. The internal driving mechanism of water resources utilization decoupling is analyzed in depth through the driving factor decomposition of different industries in the Beijing-Tianjin-Hebei region. The results show that: CD Dual control action in Hebei has significant effect, followed by Beijing and Tianjin. Since beginning of the the Tenth Five-Year Plan period, the overall economic development of Beijing, Tianjin and Hebei has shown a stable 'strong decoupling' trend from water resources utilization. However, Beijing and Tianjin are still in a 'weak decoupling' situation, and Hebei Province is in a strong decoupling' situation. Among them, the industrial and agricultural economic development and water resources utilization in the Beijing-Hebei region presents a relatively stable 'strong decoupling' situation. Hebei' s overall water resources utilization has a significant impact on the 'strong decoupling' of the Beijing-Tianjin-Hebei region, Beijing's water resources utilization of the service industry has a significant impact on the 'strong decoupling' of Beijing, and the water resources utilization of the industry and agriculture in the Tianjin-Hebei region has a significant impact on the 'strong decoupling' of Tianjin-Hebei region. (2) The effect of technical progress of industrial water resources utilization on the Beijing-Tianjin-Hebei region is significant, which is the key driving factor of water resources utilization decoupling in the Beijing-Tianjin-Hebei region. In the first half of the Fifteenth Five-Year Plan period, the structural adjustment of agricultural water resources utilization has become one of the key driving factors to realize the decoupling of agricultural economic development and water resources utilization in the Beijing-Tianjin-Hebei region. However, the service industry in the Beijing-Tianjin-Hebei region has not yet reached the 'inflection point' of water consumption peak and water consumption increment. It is urgent to enhance the capacity of water conversancy science and technology innovation, increase the intensity of water use in the service industry, and speed up the structural transformation and upgrading of the service industry, so as to exert the driving effect of structural adjustment on water resources utilization of the service industry in the Beijing-Tianjin-Hebei region. [ABSTRACT FROM AUTHOR]

The development of rural tourism can not only stimulate the growth of local economy, but also promote the effective implementation of China's rural revitalization strategy. Exploring the antecedent variables and forming mechanism of residents' support for tourism is an important factor to promote the sustainable development of tourism, which has attracted widespread attention from the academic community. Specifically, in the complex relationship between multi-stakeholders triggered by rural tourism development, residents' trust in government has played a pivotal role in ensuring the development of rural tourism, but existing studies about the influence of residents' trust in government on support for tourism lack in-depth discussion. Based on the social exchange theory, this paper takes community involvement and residents' perception of tourism impact as mediators and place attachment as the moderator. Selecting eight representative rural tourism destinations in Shandong Province as study sites, this study attempts to analyze the influencing mechanism of resident's trust in government on the support for tourism. Findings suggest that: (1) Trust in government has significant influence on community involvement, perceived benefits, support for tourism positively, and perceived costs negatively. (2) Community involvement and perceived benefits mediates partially the relationship between government trust and tourism development support. (3) Place attachment moderates the relationship between trust in government and community involvement positively. Compared with existing studies, this paper analyzes the formation mechanism of residents' support for tourism development in rural tourism destinations from the perspective of trust in government, and strengthens the role of community involvement and place attachment in the exploration of influencing mechanism. It provides a theoretical explanation and an empirical support for the deep understanding of the transmission mechanism of residents ' trust in government influencing their support for tourism and stimulating residents' support behavior for tourism development. This means that, in order to effectively improve residents' support for tourism, it is necessary to pay more attention to community residents' trust in government, enhance the interaction and communication between government and residents, encourage residents' involvement in tourism development, strengthen residents' sense of gain from rural tourism development, and cultivate residents' place attachment to their communities, so as to exert the positive role of rural tourism in promoting rural revitalization. [ABSTRACT FROM AUTHOR]

In order to solve the radio frequency (RF) stealth performance evaluation problem of aircraft swarm in air combat mode, an evaluation algorithm based on normal wiggly hesitant fuzzy set (NWHFS) is proposed. Firstly, a weight-determining model based on the best-worst method (BWM) with normal wiggly hesitant fuzzy information is constructed, the attribute weight vectors and consistency check coefficients are obtained. Secondly, based on the swarm's frequency equipment parameters and specific air combat scenarios, the RF stealth performance evaluation factors and their calculation formulas are obtained. And then, a evaluation matrix based on evaluation factor and its subjective experience is constructed and the attribute weight vector is used to aggregate the evaluation information. Finally, the NWHFS score function is used as evaluation index to quantitatively evaluate the RF stealth performance of aircraft swarm in different scenario. Simulation example and comparison analysis verify the feasibility and effectiveness of the proposed evaluation method. [ABSTRACT FROM AUTHOR]

Aiming at the problem of flight conflict resolution and track recovery of unmanned aerial vehicle (UAV) with complex obstacles in the fusion airspace, a geometric optimization method based on the velocity obstacle method is proposed, and the problem is described in strict mathematics. Firstly, according to the relative position and speed relationship between the UAV and the obstacle, the conflict type is determined based on the track pre-propelling model, and whether the conditions of each resolution strategy are met is also determined. Secondly, the corresponding resolution strategy is selected. After the resolution of the conflict is completed, the UAV will resume the original flight path. Then, geometric analysis and theoretical derivation prove that the model can effectively solve the flight conflict, and give the specific time of conflict resolution and track recovery. Finally, in the simulation, the proposed method chooses the conflict resolution strategy autonomously according to different sceneries, which shows that this method is simple and efficient. [ABSTRACT FROM AUTHOR]

Stubble clearing units are the key part of seedbed servicing device with rotating rigid cutter. In order to understand the effects of stubble clearing units on working performance and load when the knife teeth configuration rotation direction was different, the structure and the function of the left and right spiral stubble-clearing units were introduced at first, and then the conditions were acquired on the pitch of stubble clearing units through theoretical analysis. Based on this, stubble clearing units were designed about the corn planting of a big ridge and 2 rows, kinematic simulation model was built and kinematic simulation was done. The simulation results verified the correctness of the conditions on the pitch of stubble clearing units. The impact law has been got by comparative analysis, which was as follows: the knife shaft of clearing units moved longitudinally and rotated sidewise; for the 2 stubble clearing units, all knife teeth along the circumference impacted the field one after another according to the order of 123456789, and the impact location sequence of left spiral stubble clearing unit along working direction was 186429753 and the right was 594837261; for single-head knife teeth, impact direction of left spiral stubble clearing unit was the same with working direction, the spacing between adjacent knife teeth was 4 pitches, and the unit adopted jumping impact mode, but the right had opposite impact direction, the spacing between adjacent knife teeth was 2 pitches, the unit's impact mode was push-type, and the 2 units had the same spiral feeding pitch and cutting pitch. In order to acquire the load condition by simulation and do a further theory analysis, the simplified three-dimensional model of left-right spiral clearing units was built by SolidWorks, the intermediate file was exported into ANSYS/LS-DYNA, then the mesh generation was performed and the constraints were added on the model; the driving parameters were set according to actual working condition, the working process of knife teeth soil cutting was simulated, and total force and dispersion of both spiral clearing units on the yoz plane were selected as evaluation indices to do a comparison analysis. The results showed that total force and dispersion of left and right spiral clearing unit were 0.0658 kN, 66.2 and 0.062 kN, 60.1, respectively, and the right was smaller than the left. The results indicated that the right spiral clearing unit had a smaller load and load wave. Meanwhile, field performance contrast experiments had been done under the same working condition and test condition, and the mean value and standard deviation of torsion and stubble clearing ratio were selected as indices to do a contrast analysis. The results showed that the mean value and standard deviation of the torsion of left and right spiral clearing unit were 64.6 Nm, 7.2 and 62.7 Nm, 5.1, respectively, which were the same with simulation results. In the field experiment, the right was smaller than the left, and the stubble clearing ratio of the right was 95.3%, bigger than the left that was 93.8%, all indexes except stubble clearing ratio of the right is smaller than the left, which indicated that the right spiral stubble clearing unit had smaller torque and fluctuating load and had a better working performance. The research has a certain reference value for the research of tillage machine with configuration property. [ABSTRACT FROM AUTHOR]

Low temperature inhibits the performance of nitrogen removal efficiency during the biological treatment of municipal wastewater. Therefore, the effluent could hardly meet the emission standard. To enhance the performance of nitrogen removal at low temperature, a psychrotolerant aerobic denitrification consortium by fast enrichment and domestication was obtained, which could remove the ammonia, nitrate and organic matter simultaneously and efficiently in aeration environment under 10 °C. The results showed that the removal efficiency of ammonium and total nitrogen by bioaugmentation was improved by 10.31%-16.89% and 25.07%-32.44%, respectively. It made the effluent quality meet the grade lA level of national discharge standard. After bioaugmentation terminating for 10 days, the remained consortium could still improve the reactor that the effluent of ammonium, nitrate, total nitrogen and CODCr concentrations was decreased about 2.43, 3.07, 6.02 and 3.63 mg/L, respectively. The results indicated that bioaugmentation performed well and persistently. [ABSTRACT FROM AUTHOR]

The article presents a study of the effects of genetic polymorphism of the Chemokine receptor 1 (CXCR1) gene and its relationship with milk traits and somatic cell score (SCS) in Holstein cows imported from Australia. The study used polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique to analyze the polymorphism of CXCR1 gene. Results showed that CXCR1 gene genetic diversity has significant effect on milk traits and mastitis resistance.

Sustainability is the theme of our time and also the grandest challenge to humanity. Since the 1970s, the term, sustainable development, has frequently appeared in the scientific literature, governmental documents, media promotions for public goods, and commercial advertisements. However, the science that provides the theoretical foundation and practical guidance for sustainable development-sustainability science-only began to emerge in the beginning of the 21st century. Nevertheless, the field has rapidly developed in depth and expanded in scope during the past decade, with its core concepts and research methods coalescing. China, as the most populous country in the world and home to the philosophical root of sustainability science-the unity of man and nature, is obligated to take upon the challenge of our time, to facilitate global sustainability while pursuing the Chinese Dream, and to play a leading role in the development of sustainability science. Toward this grandiose goal, this paper presents the first Chinese introduction to sustainability science, which discusses its basic concepts, research questions, and future directions. Sustainability science is the study of the dynamic relationship between humans and the environment, particularly focusing on the vulnerability, robustness, resilience, and stability of the coupled human-environment system. It is a transdisciplinary science that integrates natural sciences with humanities and social sciences. It hinges on the environment-economy-society nexus, and merges basic and applied research. The key components of sustainability often change with time, place, and culture, and thus sustainability science needs to emphasize multi-scale studies in space and time, with emphasis on landscapes and regions over a horizon of 50 to 100 years. It needs to focus on the relationship between ecosystem services and human well-being, as influenced by biodiversity and ecosystem processes as well as climate change, land use change, and other socioeconomic drivers. Landscape sustainability is at the core of sustainability science, and is expected to be a hot research topic in the next few decades. [ABSTRACT FROM AUTHOR]

To enhance the management of QHD32-6 oilfield electric pump wells and predict effectively the probability of faults of electric pump units, fuzzy comprehensive judgment method is applied to establish the element set, weight set and judgment set of faults of electric pump units, to provide the calculation method of risk coefficient of influencing factor and criterion of risk evaluation level of single well and to establish the fault prediction model of electric pump units. This method can predict the wells with high fault probability of operating electric pump unit. The actual application shows that the accuracy of application of this method in fault probability prediction of units was 77.78% in the first half of 2013 and accumulative production loss saved is 7,075 m³. The predict accuracy of this method can meet the demand for engineering and technical analysis to provide technical support for optimized management of electric pimp. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this study was to culture and identify dental pulp stem cells(DPSCs) from deciduous teeth in vitro and construct the recombinant hFOXA2 and hPDXl lentivirus vectors and transfect the DPSCs to induce insulin-producing cells (IPCs). METHODS: DPSCs were separated and cultured by enzyme digest method, and purified by limited dilution method. Flow cytometry was used to determine the surface marker expression of the DPSCs, and the ability of multiple differentiations was determined by specific staining. hFOXA2 and hPDX1 genes were amplified by PCR, and the recombinant hFOXA2 and hPDX1 lentivirus vectors were reconstructed and transfected into 293T cells by Iipofectamine2000 for virus packaging. The viral infection efficiency and titer were determined through fluorescence cell count. The recombinant virus was used to infect the DPSCs cells via multiplicity of infection (MOI)and induce the DPSCs reprogramming for IPCs. Immunofluorescence staining was used to measure the expression of proinsulin, FOXA2 and PDX1. ELISA method was used to detect the insulin secretion. The data was analyzed Using SPSS13.0 software package. RESULTS: DPSCs were isolated and cultured successfully. Cell surface highly expressed STRO-1 (98.01%), CD146 (98.51%), CD34 (99.54%) and CD45 (24.08%). The multi-lineage differentiation capacity into osteoblasts, chondrocytes, and adipose was achieved. The recombinant hFOXA2 and hPDX1 lentivirus vectors were successfully constructed. Double enzyme digestion and sequencing appraisal showed that the sequence was fully consistent with GenBank retrieval. Virus packing efficiency was (96.15+0.17) % and (95.49±0.21) % respectively, and the infection titer was about 1.80x10[sup 8][GTU/mL. The best MOI of the virus was 20. After inducing the cells to express proinsuhn, FOXA2 and PDX1, insulin secretion volume was about 1.92 µmol/L. Compared with the uninduced group and control group, insulin secretion increased significantly (P<0.01). CONCLUSIONS: The recombinant transcription factor virus can activate cell reprogramming mechanism, form insulin-producing cells, and can be used for gene therapy of diabetes seed cells. Supported by Science and Technology Research Program of Shaanxi Province (2009K17-06) and Science and Technology Innovation as a Whole Plan Resources Leading Industry Key Technology (Chain) Project of Shaanxi Province (2011KTCL03-24). [ABSTRACT FROM AUTHOR]

To optimize the fermentation parameter of Klebsiella. sp, orthogonal experiments were used to quantify the degree of the fermentation parameters of flocculant-producing bacteria MFX on the flocculation rate and the yield, which indentified temperature, shaking revolution and pH value as the input of neural network, flocculation rate and yield as the output of neural network, and then a training sample was designed. After repeat training, a prediction model with high accuracy and small error was established by which the optimum fermentation conditions: the temperature of 33 °C, the stirring speed at 141 r/min and pH value of 7.90, were obtained. Meanwhile, the actual flocculation rate and the yields were 92.67% and 2. 180 9 g/L, respectively. The flocculation rate increased 4.08%, and the yields of bio-flocculant increased 14.36%, which improved the yield of bio-flocculant. The model was used to predict the fermentation process of flocculant-producing bacteria F + in the fermenter, the simulation error was small, which was the basis for the prediction and control of industrial fermentation process. [ABSTRACT FROM AUTHOR]

Taking the DH population of wheat cultivar Hanxuan10/ Lumai14 as test object, and by the methods of correlation analysis and path analysis, this paper studied the relationships of the flag leaf stomatal density (SD), stomatal length and width (SL and SW), stomatal conductance (gs), photosynthetic rate (Pn), and transpiration rate (Tr) on the 10th and 20th day after anthesis with the yield and the index of drought-resistance under the conditions of drought stress and normal irrigation. Under the two conditions, most of the test leaf traits on the 10th day after anthesis had less correlation with the yield and the index of drought-resistance, whereas the leaf traits on the 20th day after anthesis had significant positive correlations with thousand kernel weight but less correlation with grain number per ear, grain yield per plant, and index of drought-resistance. Path analysis showed that gs, Pn, and Tr were the main factors affecting the grain yield per plant (YPP) and the index of drought resistance (IDR), and the effects were stronger both in direct and in indirect ways. The direct and indirect effects of SD, SL, and SW on the YPP and IDR were lesser. Under both drought stress and normal irrigation, and on the 10th and 20th day after anthesis, there were significant correlations between SD and SL, and between SL and SW, gs, Pn, and Tr, but the correlations of SD and SL with gs, Pn, and Tr changed with water condition or growth stage. Therefore, it would be not always a good means to select the leaf stomatal density and size as the targets for breeding to improve the leaf stomatal conductance, photosynthetic rate, and transpiration rate, and further, to promote the yield. [ABSTRACT FROM AUTHOR]

To explore the feasibility of dual release baicalin and rhBMP-2 system for the treatment of periodontal diseases in minipigs. METHODS: Four miniature swines were selected to establish the model of periodontitis and randomly divided them into four groups: Dual release group, hydrogel with baiealin-GMS and rhBMP-2; Single Huang group, hydrogel with baicalin-GMS; BMP group, hydrogel with rhBMP-2; Negative control group, blank hydrogel. All parameters including clinical indicators of periodontitis, the level of IL-1 and TNF-α in the gingival crevicular fluid (GCF) were measured before and 6 weeks after modeling, and 4, 8 weeks after treatment. The data was analyzed using SPSS13.0 software package. The periodontitis model animals were sacrificed at the end of 8 weeks after treatment. The histological changes of periodontal tissues were observed under microscope with HE staining. RESULTS: (1)In all groups, there were significant differences of clinical indicators and levels of IL-1 and TNF-α in the GCF between periodontitis was established and 4, 8 weeks after treatment (P<0.05). Dual release group was significantly superior than that of other three groups (P<0.05). Moreover, all the parameters improved continuously. X-ray showed that bone mineral density and height in the remaining three groups increased compared with the control group, with highest in dual release group. (2)The results of histological observation showed that the inflammation reaction of periodontal tissues in negative control group was more serious than that in other groups 8 weeks after treatment. There was no obvious repair reaction in the control group, but different amount of new bone was seen in other three groups. Among them, dual release group had most obvious repair reaction. CONCLUSIONS: The dual-slow-release chitosan thermosensitive hydrogel system is employable to be used effectively in the regeneration of periodontal defects, which laid a foundation for further clinical use. Supported by National Natural Science Foundation of China (81173311) and Key Project of "13115" Science and Technology Innovation Program of Shanxi Province(2009ZDKG-77). [ABSTRACT FROM AUTHOR]

Microbial culture-independent technology, such as DNA fingerprinting technology, pyrosequencing, molecular hybridization technology, metagenomics, metatranscriptomics, metaproteomics, metabolomics and so on, has developed rapidly and been applied extensively in many fields, which could assist in the identification of microbial species from natural or anthropogenic environment rapidly and accurately. The microbial culture-independent technology has provided crucial in-sights for revealing microbial community structures, functions and remediation mechanism during bioremediation process and improving the detection efficiency of bioremediation. This review is mainly focused on the advanced applications of molecular biology and microbial culture-independent technology of "-- omics" in gauging microbial community structures, functions and dynamics at contaminated areas. [ABSTRACT FROM AUTHOR]

Extraction of metagenomic DNA from environmental sample was the main restrictive factor for the metagenomic sequencing. Three different extraction methods were used and compared in this study. The results indicated that the metagenomic DNA obtained from the activated sludge by Liquid Nitrogen Grinding + DNA Extraction Kit was the best sample due to the largest information and best quality, and D (260/280 nm) was between 1. 69 -1. 72. During the sample preparation for the next generation sequencing, D (260/280 nm) of the metagenomic DNA reached to 1. 83 after purification, which met the requirement of library construction. After the sequencing by Solexa Genome Analyzer System, the results showed that the forward sequencing of these two samples was successful, and the high quality data was about 90. 8%, which could be used for assemble. [ABSTRACT FROM AUTHOR]

To improve demulsifying property, the original biodemulsifier-producing bacterium, Bacillus mojavensis XH1, was mutated and bred by the combined treatment method using UV irradiation and niitrosoguanidine (NTG). A high efficient biodemulsifier-producing mutant XN5 with the better stability was obtained after continuous passages. The optimal cultural conditions were as follows: the mixture of 10 g/L glucose and 4 % liquid paraffin is the carbon source, the mixture of 4.0 g/L NH4Cl and 1.0 g/L yeast extract is nitrogen source, pH =6. 5 , the rotating rate is 140 r/min and the incubated time is 24 h. The 12 h and 24 h demulsification ratios of the mutant XN5 were 94. 17% and 98. 67% , which were 64. 81% and 15. 12% higher than that of the original strain XH1, respectively. [ABSTRACT FROM AUTHOR]

Taking the solar greenhouses with different cultivating years and vegetables in Ji爷nan as test objects, this paper studied the amounts and frequency distribution of soil nutrients and the rela tionships between cultivating years and soil nutrients accumulation characteristics, and analyzed the factors causing soil salinization and acidification by fitting soil nutrients contents with cultivating years and vegetables. In the greenhouses, the contents of soil alkalihydrolysable nitrogen, availa ble phosphorus, available potassium, organic matter, and electrical conductivity were significantly higher than those in the open field, with an increment of 135. 3%, 475. 2%, 290. 1%, 97. 7%, and 188. 7%, respectively, but the soil pH value was 0. 31 lower than that of open field. The fre quency distribution of soil nutrients presented a normal curve. Differences were observed in the soil nutrients contents in the greenhouses with different cultivating vegetables. The soil alkalihydrolys able nitrogen content and electrical conductivity were in the order of tomato > cucumber > sweet pepper, soil organic matter content and pH value were cucumber > sweet pepper > tomato, soil available phosphorus content was cucumber > tomato > sweet pepper, and soil available potassium content was tomato > cucumber > sweet pepper. There was a mild tendency of soil acidification in the greenhouses, and the aggravation of soil salinization was primarily caused by the accumulation of soil alkalihydrolysable nitrogen and available potassium. The decrease of soil pH was closely related to the accumulation of alkalihydrolysable nitrogen. The soil nutrients accumulation in the green houses had the similar patterns, i. e. , rapid accumulation in the first two cultivating years, slowed down in the third and fourth year, and kept stable later, demonstrating a dynamic balance on the whole. All the nutrients contents were positively accumulated, while soil pH presented negatively. In the greenhouses with different cultivating vegetables, there was a significant correlation between soil nutrients and cultivating years, which could be fitted by conic curve or cubic curve. [ABSTRACT FROM AUTHOR]

In this paper, 16 denitrifying phosphate --accumulating organisms (DNPAOs) were isolated in the special medium from the anaerobic/aerobic/anoxic SBR reactor, and the most efficient DNPAOs called Q -- hrb05, was screened by a phosphate uptake experiment, where nitrates were denitrified to gas and through inspection of the poly -- P. Strain Q -- hrb05 was identified by 16S rDNA gene analysis, and the accession number of 16 S rDNA gene sequence of strain Q -- hrb05 in GenBank was GU214826. The result showed that the strain Q -- hrb05 belonged to Bacillus sp, of which the homology could reach to 99%, that also corresponded to the result of biochemical features. The average phosphorus uptake rate of strain Q -- hrb05 was at 85% within 12 hours, and it had the denitrification capacity in the aerobic condition. It could be found that the phosphorus uptake rate was related to the content change of PHB. Under anaerobic condition, the maximal P -- release rate was 66%, which could reach to 12% of the dry cell weight. The P -- uptake rate was 92% with the decreasing of PHB content. [ABSTRACT FROM AUTHOR]

PURPOSE: To detect the effect of naringin on human periodontal ligament cells' (hPDLCs) proliferation, bone formation and OPG mRNA expression. METHODS: hPDLCs were primarily cultured and identified in vitro through enzyme digestion combined tissue culture method. With 3-(4, 5-Dimethyhhiazol-2- yl)-2, 5-diphenyhetrazolium bromide (MTL) method ,enzyme linked immunosorbent assay and RT-PCR, the hPDLCs' proliferation, alkaline phosphatase (ALP) activity , expression of collagen protein-I and OPG mRNA were observed after treatment with different concentrations (100,10,1.0,0.1,0.01 mg/L) of naringin at different times. SPSS 16.0 software package was used for statistical analysis. RESULTS: Primary cultured hPDLCs had good shape; Significant promotion of proliferation, ALP activity and collagen protein- I expression of hPDLCs with naringin was found at the dose of 1.0 mg/L; and 1.0mg/L naringin regulated the expression of OPG mRNA in time-dependent manner. CONCLUSION: Naringin might significantly promote the proliferation of hPDLCs and conversion into the osteoblast. Supported by National Natural Science Foundation of China (30940092) and "13115" Major Scientific and Technological Innovation Special Projects of Shanxi Province (2009ZDKG- 77). [ABSTRACT FROM AUTHOR]

To reveal the relationship between microorganism and pollutants' degradation in the stability system of the municipal wastewater treatment plant, the dynamic monitoring of microbial community structure and metabolic activity of the stable operation biological system in biological wastewater treatment plant was carried out using the denaturing gradient gel electrophoresis (PCR - DGGE) and Biology Technology. The results showed that the average removal efficiency of effluent Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and TN was more than 84.4%, 84.7% and 59.8%, respectively. The microbial community structure was stable in the different sites of biological system in the same season, and the ecological niche of predominant functional species including Bacillus , Pseudomonas, Aeromonas was stable. As the temperature increased in spring, the quantity and diversity of population increased significantly. Meanwhile, metabolic activity strengthened in biological system, which could improve the removal rates of pollutants. It is feasible to use the two methods to monitor the changes of microbial community structure of biological system in a wastewater treatment plant at low temperature. [ABSTRACT FROM AUTHOR]

PURPOSE :To clone the peptidylarginine deiminase(PAD) gene of Porphyromonas gingivalis (P.gingivalis) and to be expressed in E. coli under the best conditions. METHODS: With P.gingivalis strains ATCC33277 genomic DNA as a template, PCR was applied to obtain gene PAD which was then inserted into linear cloning vector PMD-18-T to construct clone recon. Recombinant PMD18--T-PAD was cloned and analyzed with PCR and restriction endonuclease, and PET--28a expression vector was digested by Xhol and Ncol,their products were linked to construct expression plasmid PET--28a--PAD under certain connection system. The recombinant expression plasmid PET-28a--PAD which had been confirmed correctly was transformed to E. coli competent cells BL21 and induce the expression of PAD with IPTG of different density and time. With His Tag monoclonal antibody as the first antibody, the expressed fusion protein was characterized by Western blot. RESULTS:DNA sequencing showed that the fragment was same as the sequence published in NCBI. Under the condition of 37°C, 0.5mmol/L IPTG, 250r/min shaking for 6 hours, the PAD could be highly expressed. CONCLUSIONS: The PAD is successfully cloned and expressed in E. coli which can be further used to study the immunity of PAD and the homologues antibody preparation. Supported by National Natural Science Foundation of China (30500560) and Natural Science Basic Research Plan of Shanxi Province(2006C242). [ABSTRACT FROM AUTHOR]

Based on the field experiments with different plant-type wheat (Triticum aestivum) cultivars and varied population densities, the time-course changes in the angle between stem and sheath (stem-sheath angle) on main stem were observed, and a process-based model was developed for simulating the growth dynamics of stem-sheath angle on the main stem by using system analysis method and dynamic modeling technology. The stem-sheath angle increased with the growth of corresponding leaves, and decreased with increasing population density. The maximum stem-sheath angle decreased with increasing leaf position, except for the first leaf on main stem. The growth dynamics of stem-sheath angle could be described with Logistic equation, and the changes in the maximum stem-sheath angle with leaf position could be quantified with two different equations. The maximal value of stem-sheath angle at the second leaf position was considered as the cultivar parameter to reflect the genetic differences, and the plant number per unit area was used to quantify the effects of population density. The independent field experiment dataset of different wheat cultivars was used to test the model, and the average RMSE between estimated and observed values was 1.7°, suggesting that the present model had good performance and reliability on predicting the growth dynamics of wheat stem-sheath angle, and provided a key module for wheat plant-type simulation and visualization. [ABSTRACT FROM AUTHOR]

Objective To clone ihe glyceraldehydes 3-phosphate dehydrogenase (GAPDH) gene of Porphyromonas gingivalis (.P.gingivalis) and to induce its fusion expression in E.coli. Methods GAPDH was obtained by PCR and was inserted into cloning vector pMD-18-T to construct clone recon. Double enzymes digest the recon pMD18-T-GAPDH and the prokaryotic expression vector pET-32a and then connect to get the expressing recon pET-32a-GAPDH. The recombinant expression plasmid which had been confirmed by enzymes digestion was transformed to E. coli competent cells BL21 and induced the expression of GAPDH with isopropyl ß-D-1-thiogalactopyranoside (IPTG) of different density. Results DNA sequencing showed that the fragment was 99.802% the same to the sequence pub-lished in NCBI. Under the best density, IPTG could be highly expressed. Conclusion The CAPDH had been success-fully cloned and expressed in E. coli which gets ready for the following experiment to study the immunity of GAPDH and the homologues antibody preparation. [ABSTRACT FROM AUTHOR]