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The effect of different electron beam refining parameters on the type， quantity and size distribution of inclusions during melt solidification was studied. The content of O and N in FGH4096 alloy and the type， quantity and size distribution of inclusions after different power refining were statistically analyzed， and the mechanism of influence of power on inclusions growth during electron beam refining was revealed in combination with the growth kinetics of inclusions. The number density of carbon and nitrogen compounds and complex phase inclusions in FGH4096 alloys prepared by electron beam refining was the largest， and the proportion of both was 95.53%. In the carbon nitrogen compounds and complex phase inclusions， TiN-TiC， TiN-（Ti，M）C and Al2O3-TiN-（Ti，M）C occupied a large proportion. The inclusions growth kinetics calculations showed that when the power increased from 9 kW to 12 kW， the increased power improved the removal effect of the inclusions forming elements， limited the elemental content required for the growth of inclusions， reduced the formation temperature of inclusions and thus reduced its growth temperature range， and led to a reduced growth time and size of inclusions due to the small change in the cooling rate additionally.However， when the power 12 kW increased to 15 kW， the O and N content decreased less while the melt cooling rate decreased larger， resulting in an increased growth time of the inclusion.It reduced the effect of the removal of impurity element content， with an increase in the size of inclusions.

Objective: To investigate the effect of M2 macrophages on the proliferation, migration and invasion of gallbladder carcinoma cells by regulating the expression of interleukin-10 (IL-10). Methods: Human monocyte line THP-1 was induced into M2 macrophages in vitro, and the expression of corresponding markers and IL-10 was detected by RT-qPCR. The expression of IL-10 in cell supernatant was detected by ELISA. GBC cell lines NOZ and GBC-SD were divided into the Control group (serum-free medium), the M2-CM group (M2 macrophage conditioned medium), the M2-CM+anti-IL-10 group (M2-CM containing anti-IL-10) and the M2-CM + IgG group (M2-CM containing IL-10 isotype control antibody). The cell proliferation rate of each group was measured by CCK-8 test, the cell migration rate of each group was detected by cell scratch test and the change in cell invasive ability of each group was detected by Transwell test; and Western blot assay was used to detect the expression of epithelial-mesenchymal transformation markers (E-cadherin and Vimentin) in each group. Results: M2 macrophages were successfully induced in vitro. Compared with uninduced THP-1, IL-10 was highly expressed in M2 macrophages and M2 macrophages supernatant (P<0.05). M2 macrophages could promote the proliferation, migration and invasion of GBC cells, as well as inhibit the expression of E-cadherin and promote the expression of Vimentin. Blocking IL-10 could inhibit the effect of M2 macrophages (P<0.05) . Conclusion: M2 macrophages can promote the proliferation, migration, invasion and epithelial-mesenchymal transformation of GBC cells by secreting IL-10. [ABSTRACT FROM AUTHOR]

Objective To investigate the antibacterial activity to Streptococcus mutans of a nisin⁃containing single⁃ bond universal adhesive. Methods Nisin was mixed into the bonding agent to produce concentrations ranging from 0.01 g/mL to 0.05 g/mL for the experiments, and adhesive without nisin was used as the control. Dentin⁃resin specimens were prepared for the microtensile strength test to evaluate changes in the bonding strength. The proper concentrations were selected for more tests. ① An agar diffusion test was applied with filter paper to detect the release of nisin, and adhesive without nisin was used as the negative control, 0.01 g/mL Nisin aqueous solution was used as the positive control. ② Solidification; resin adhesive specimens were prepared for the assessment of direct contact inhibition activity. ③ Confocal laser scanning microscopy was used to examine the effect of the adhesive on the biological film activity and the ability of Streptococcus mutans to produce extracellular polysaccharides. Results Nisin did not significantly reduce the bond strength of the modified adhesive at 0.01⁃0.03 g/mL (P < 0.05); these concentrations were selected for the subsequent antibiosis experiment. Rings could not be observed in the agar diffusion test, except for in the group of adhesive modified with 0.01⁃0.03 g/mL nisin. Resin adhesive with 0.01⁃0.03 g/mL nisin could significantly inhibit the proliferation of Streptococcus mutans on the surface of the specimens. The confocal laser scanning microscopy results indicate that only the adhesive resin modified with nisin could reduce the bacteria in the biofilm and the production of extracellular polysaccharides. Conclusion Single⁃bond universal adhesive with 0.01⁃0.03 g/mL nisin can inhibit the growth of Streptococcus mutans and its biofilms on the bonding interface, as well as decrease the production of extracellular polysaccharides, and thus has the potential to decrease the occurrence of secondary caries.

As the first defensive line for the safety management of hazardous chemicals, the relevant safety access system must be strictly controlled. This paper expounds the thinking and practice of safety access for hazardous chemicals towards the three directions of 'people', 'object' and 'environment'. Organizing safety education and training in a full, comprehensive and whole process, and combining the experimental safety risk emergency response plan with the personal subject is to achieve the safety access of 'people'. Purchasing hazardous chemicals in a accordance with the law as well as the fine ledger management, ensuring the clear source and usage flow is to achieve the safety access of 'object'. Implementing an environmental management system based on the '5S' management concept is to achieve 'environmental' safety access. Through multi-directional and multi-dimensional exploration, we will gradually establish and improve the safety access system for hazardous chemicals in laboratories, in order to provide effective and feasible solutions for the scientific management and safe use of hazardous chemicals in universities, aiming to prevent laboratory safety accidents. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries are widely used in many fields because of the advantages of high energy density, excellent cycling performance, and low self-discharge rate. Nevertheless, the specific capacity of lithium-ion batteries cannot satisfy the practical demands further after being employed for 3 to 5 years due to the decomposition of liquid electrolytes, which can lead to a large number of spent lithium-ion batteries undoubtedly. Therefore, recycling and utilizing of spent lithium-ion batteries reasonably can not only economize the resource, but also alleviate the environmental pollution. This paper summarizes the processing steps of spent lithium-ion batteries during the recycling process, which mainly consists of the pretreatment of ternary cathode materials, the leaching and separation of valuable metal ions and the regeneration of ternary cathode materials as well as comparing the advantages and disadvantages of various methods. On that basis, it is reasonable to move in a safe, environmental and efficient direction to recycle and utilize of ternary cathode materials in spent lithium-ion batteries. [ABSTRACT FROM AUTHOR]

In order to fully analyze and tap the yeast strain resources in the fermented grains of Luzhou-flavor liquor, high-throughput sequencing and pure culture were carried out for the fermented grains in the vigorous period of Wuliangye fermentation. Among them, a total of 11 species of yeast were detected by high-throughput sequencing technology, including Kazachstania exigua, Saccharomyces cerevisiae, Kazachstania Humilis, Pichia kudriavzevii, Zygosaccharomyces bailii, Saccharomycopsis fibuligera, Trichosporon ovoides, Debaryomyces hansenii, Naumovozyma castellii, Pichia manshurica, Geotrichum silvicola. The yeast strains in the fermented grains of Wuliangye at the vigorous fermentation stage were screened by 7 kinds of culture media. 57 strains of pure culture yeast were obtained by merging. Through the sequence identification of 26S rDNA, it was found that they belonged to Pichia kudriavzevii, Saccharomyces cerevisiae, Candida glabrata and Candida rugosa. The results showed the rich diversity of yeast population in fermented grains of Luzhou-flavor liquor. Nonetheless, compared with the high-throughput sequencing means, the pure culture method could only isolate a few species in the septic yeast population. Thus, it was necessary to dig out the yeast strain resources in the fragrant white wine dregs and further optimize the separation and culture methods. [ABSTRACT FROM AUTHOR]

To study the strip Wongawilli mining coal pillar failure evolution characteristics and its control technology, enrich the research foundation of strip Wongawilli mining theory. This paper adopts the method of theoretical analysis and similarity simulation to observe and analyze the damage evolution characteristics of coal pillar in strip Wongawilli mining, and the control measures are put forward. The results show that the ultimate performance of the coal pillar rock sample is that it is almost parallel to the axial direction, and the bearing capacity is influenced by the type, size and support of the coal pillar, and there are 3 main forms of the failure and deformation of the coal pillar. [ABSTRACT FROM AUTHOR]

The super-peer networks adopt two-layer structure to organize super-peers and ordinary peers to improve the performance of network and the search efficiency. However, the dynamic maintenance and search routing mechanism of current network topology will lead to complexity of dynamic maintenance and excessive information caused by the query. To solve these problems, this paper proposed a novel HPDG (k) graph. With this structure, it constructed a new super-peer network HPDGN based on HPDG (k) graph, and presented a mechanism of dynamic maintenance and search routing. This new topology had good performance with constant degree and fixed adjacent nodes, supported proximity search and solved the issues that structured super-peer topology could not support the dynamic environment well. Simulation show that compared with current supper-peer topology, HPDGN reduces the bandwidth consuming during searching, and keeps less topology construction and failure repair cost. [ABSTRACT FROM AUTHOR]

Covariance analysis, curve-fitting, and canonical correspondence analysis (CCA) were used to explore the effects of topographic factors on the plant diversity and distribution patterns of ground flora with different growth forms in the karst mountains of Southwest Guangxi, China. A total of 152 ground plants were recorded. Among them, 37 species were ferns, 44 species herbs, 9 species lianas, and 62 species shrubs. Covariance analysis revealed that altitude significantly correlated with the individual number and richness of ground plants, and slope aspect had a significant effect on richness. Statistical analyses showed a highly significant nonlinear correlation between the individual number or richness of ground plants and altitude. Results of CCA revealed that slope aspect had a significant effect on the distribution pattern of ferns, and slope had a significant effect on the distribution patterns of herbs, lianas and shrubs. Ferns were more sensitive than herbs, lianas and shrubs to changes in heat and soil water caused by aspect. The effect of slope was stronger than that of elevation on soil water and nutrients, and it was the most important topographic factor that affected the distribution patterns of herbs, lianas and shrubs in this region. [ABSTRACT FROM AUTHOR]

In order to study the function of soil microfauna and its responses to environmental changes, we used metagenome analyses of the 18S rDNA gene region to identify differences in microfauna diversity and community structure among fifteen soil samples belonging to five different Cunninghamia lanceolate plantations. The plantations were located in Youxian County, Hunan Province in central China. The trees in these plantations were of different ages (3, 13, and 26 years) and belonged to different ecological successions (first, second, and third successions). The total dataset comprised 94922 high quality sequences with an average length of 436 bp. The dominant taxonomic groups across all samples were Chordata, Annelida, Arthropoda, Nematoda, Rotifera and Platyhelminthes with each accounting for 60. 8%, 24. 0%, 7. 4%, 3. 6%, 1. 5% and 1. 2% of the sequences, respectively. There were significant differences in ACE index and Shannon index among the five plantations. The lowest diversity of soil microfauna was in the 13-year old plantation of the first ecological succession. The correlation analysis showed that both ACE and available potassium concentration were negatively correlated to the Chao1 index. However, there were no significant correlations between the Shannon, Simpson indices and the physical-chemical properties of soil. Overall, the Jaccard's similarity coefficient was less than 0. 4 among samples at each site, and significant differences were found among plantations. [ABSTRACT FROM AUTHOR]

To scientifically select and evaluate ultra-thin wearing course asphalt mixture, three types of asphalt mixture, SMA-10, UTAC-10 and NovaChip Type-C were selected to study the performance evaluation indicator. The low temperature performance of mixture was evaluated by use of thermal stress rest rained specimen test, and the surface performance was evaluated by permeable coefficient test and anti-slide performance test. A kind of indoor abrasion test was designed to evaluate the skid resistance attenuation property of asphalt mixture, and a set of dispersion tests under three conditions was designed combining with freeze-thaw splitting test to evaluate water damage resistance performance of asphalt mixture. The results show that the frozen broken temperature and frozen broken strength can effectively evaluate the low temperature performance of ultra-thin wearing course asphalt mixture. It is scientific to use initial value of BPN and sliding attenuation degree to evaluate skid resistance performance of ultra-thin wearing course. Freeze-thaw splitting strength ratio and freeze-thaw splitting strength should be combined to evaluate resistance water damage performance. [ABSTRACT FROM AUTHOR]

To prepare high-viscosity asphalt for drainage asphalt pavement in China, the effect of TPS contents and kinds of base asphalt on the properties of modified asphalt was investigated by tests in laboratory. The 60 °C dynamic viscosity is an important parameter for high-viscosity modified asphalt. The results indicate that strong correlations exist between the chemical composition of base asphalt and the properties of TPS modified asphalt. The viscosity of modified asphalt at 60 °C increases with the increasing of asphaltine content of base asphalt at same contents of TPS. When the TPS content is between 14% - 16%, it has significant influence on viscosity of modified asphalt at 60 °C, the viscosity increases rapidly, and can reach to specifications for high-viscosity modified asphalt. The temperature sensibility of the asphalt modified by TPS is decreased obviously, and the high-temperature stability, cracking resistance at low temperature and elastic recovery are all increased. [ABSTRACT FROM AUTHOR]

In order to obtain the CA mortar that can satisfy high-speed railway construction, CA mortar with different proportion was prepared. Through studying strength of CA mortar and Observating its microstructure by scan electron microscopy, the strength and its development of CA mortar was studied by changing sand gradation, the ratio of sand to cement and the ratio of asphalt emulsion to cement. Results show that using combination of two kinds of sand with particle size of 0. 15 -0. 3 mm and 0. 3 -0. 6 mm in CA mortar can reduce the material separation greatly while posing little effect on the 28 d compressive strength of high strength CA mortar. With the increment of m (S)/m (C) , the 1 d compressive strength of high strength CA mortar increases but the 28 d compressive strength doesn't change initially until reaching the critical point 1.4, which drags huge decline for it. The compressive strength of high strength CA mortar of different ages are significantly declining with the increment of m (A) / m (C). Selecting the appropriate size sand, m (S) / m (C) and m(A)/m (C) is the premise to obtain the CA mortar that can satisfy high-speed railway construction. [ABSTRACT FROM AUTHOR]

Based on the field data collected from a medium-scale experimental pavement system, temperature distribution characteristic of subgrade in seasonally frozen regions was studied in detail, and the prediction model for subgrade temperature distribution was proposed with regression analysis. Test data illustrated that: The temperature of subgrade changed with time, and it followed cosine distribution; Energy was stored with the heat transfer in subgrade, and it transferred nonlinear with depth. Based on the collected data, the prediction model for subgrade temperature distribution in this area was proposed. The comparison between measured and predicted temperatures indicated that this model had good applicability and accuracy for this area. [ABSTRACT FROM AUTHOR]

First, oscillatory differential equation with wrinkle membrane is established based on Lagrange equation and analysis flow of membrane dynamic characteristics is set up by FE program, and then post-buckling dynamic characteristics of rectangle shear membrane are studied. Results indicate that the post-buckling vibration modal of rectangle shear membrane has great correlation with wrinkle configuration. The position of vibration pitch line gets along with the position of wrinkle wave crest. With the increasing of mode number, the number of vibration pitch line is reduced sequentially, and more wrinkle waves crest at the state 6f vibration. At high order mode, local vibration is presented at the edge of membrane. As shear distance increased, the amplitude of membrane wrinkle is enlarged, and oscillatory variety takes place in natural frequency. The natural frequency is obviously reduced after buckling. [ABSTRACT FROM AUTHOR]

Numerical analysis method of membrane secondary buckling was developed. Arbitrary initial flaw was introduced into membrane by applying outside disturbance, and the phenomenon of membrane secondary buckling was analyzed. It is indicated that in the process of membrane post-buckling, the phenomenon of membrane secondary buckling appears because of initial flaw, wrinkle configuration is instable, and new wrinkles are produced. Post-buckling equilibrium path presents the multistage characteristic. In the case of different initial flaws and loading processes, the phenomenon of continuous secondary buckling emerges in the process of membrane post-buckling. It is concluded that membrane can be stable or not in the course of secondary buckling, which depends on initial flaw and loading process. [ABSTRACT FROM AUTHOR]

In order to find the main factor influencing the water stability of asphalt mixture and make it possible for the large-scale use of granite aggregate in asphalt pavement, the rheological property of asphalt mastic mixed with different granite powders and different ratios of filler to asphalt was studied using dynamic shear rheometer. The result shows that the interaction capability is different with different granite powders and asphalt. So the compatibility of granite and asphalt should be considered in the choice of materials. A freeze thaw split test was conducted to verify the relationship between the water stability of granite asphalt mixture and the interaction capability of granite and asphalt. It is indicated that there is a good corresponding relationship between the rheological property of asphalt mastic and the water stability of asphalt mixture. [ABSTRACT FROM AUTHOR]

In order to analyse the influence of coarse aggregate surface texture on performance of asphalt mixtures, surface textures of eight different coarse aggregates were measured directly adopting laser profilometer. On the basis of fractal geometry, structure function method for random process analysis was used to characterize the roughness of coarse aggregate surface texture. Adopting the quantitative evaluation method, taking the fractal dimension D and the intercept K as evaluating indices, the roughness of coarse aggregates was analyzed. Results show that fractal trait exists in the limited distance of coarse aggregate surface texture curve and the roughness of coarse aggregates nearly has nothing to do with the coarse aggregate size. [ABSTRACT FROM AUTHOR]

To analyze the similarity of stress state between rutting test and asphalt pavement, finite element simulation was carried out to modify the rutting test model based on similarity theory. Firstly, the relationship between structure of asphalt pavement and parameters of the modified rutting test model was deduced through similarity theory. Then the affected areas for three typical pavement structure under loading of wheel load were obtained by finite element simulation with ABAQUS, and the model size of the entire structure was achieved by dint of similarity theory. According to the principle of mechanical response equivalency, parameters of indoor rutting test model for the multiple board structure were determined, and the correctness of multiple board rutting model was verified by rutting test. [ABSTRACT FROM AUTHOR]

Interaction capability of asphalt and aggregate is a crucial factor to affect the engineering performance of asphalt concrete mixtures. In order to evaluate this interaction more objectively and veritably, rheological characteristics of asphalt mastics with different mineral fillers are studied based on dynamic shear test. Results indicate that it is correct and feasible to characterize the interaction with indexes of asphalt-aggregate interaction coefficient B, complex shear modulus coefficient ΔG* and comp!ex viscosity coefficient Δη. Besides, sensitivity analysis of test results shows that B exhibits higher sensitivity compared with ΔG* and Δη*. [ABSTRACT FROM AUTHOR]

By adopting the digital speckle correlation method (DICM), the tensile strain researches in the indirect tension test of asphalt mixture sample are preceded in this paper. Simulation on the tension of speckle diagram shows that the DICM is available, and its accuracy is high. Furthermore, the efficiency of DICM is proved by the comparison and analysis with the gauge measuring and calculating method. It is concluded that DICM is feasible in measuring the indirect tensile strain. [ABSTRACT FROM AUTHOR]

Casings are key components for the aero-engine,and its containment performance is a necessary condition for ensuring flight safety.Firstly,the types and structural forms of the casing related to containment are briefly introduced.Then,the impact response,damage mechanism and containment ability of casings are summarized from aspects of theoretical researches,simulation analyses and experimental tests.Besides,numerical simulation researches about casing containment are introduced according to types of casing material.Test methods about casing containment and its research progresses are analyzed.Finally,the containment research status of casings is summarized and the development tendency of casings containment is looked from the perspective of working condition,loading situations and optimization design.

In order to estimate the performance of opto-electrical tracking system, the integrated simuation platform should be developed, which is comprised of structure, control and optics. Based on the object track modeling, the tracking strategy for system is analyzed, and tracking optics principle and con- trol principle are studied separately. Finally, virtual reality is introduced. Integrated simulation platform is implemented in Matlab/Simulink. Using the platform, an example is analyzed, and the results accord with the fact. So the platform can be used in design and performance estimation in future. [ABSTRACT FROM AUTHOR]

In view of problem that traditional process water system of coal mine cannot real-timely know situations of running of pump and water level of sump with manual operation mode, a monitoring system of process water of coal mine was designed. The system includes many PLC control stations which are used to monitor pump house of surface wastewater treatment plant, underground pump houses and sumps. Each PLC control station collects data of sensors and uploads the data to upper computer through industrial Ethernet, the upper computer dispatches working pump and spare pump according to the data and makes remote operation for electric valve, so as to realize automatic control function. The actual application shows that the system realizes unmanned on duty and remote control for pump houses and improves automation level of coal mine.

In view of problem of artificial local control mode of traditional air compressor, the paper introduced a design of automatic control system of coal mine air compressor based on PLC. The system uses PLC as control core, which achieves functions of parameters acquisition, data processing, data remote transmission, fault alarm, automatic control and so on, and the system also realizes unmanned on duty for coal mine air compressor to lay a good foundation for digital mine.

Analyzing the pattern of altitudinal variation in the leaf traits and their networks of a particular tree species of similar age and its influencing factors could contribute to understanding the impacts of environmental factors on leaf traits and excluding the interference of genetic factors. We investigated the stomatal, structural, chemical, and vein traits of Daphniphyllum macropodum leaves in middle-aged forests, following the altitudinal gradient (1100, 1500, and 1900 m) on Mao'er Mountain. The objectives of this study were to reveal patterns in leaf trait and leaf trait networks variation, the life strategy of the tree species, and the major environmental factors affecting the altitudinal variations. The results showed that leaf area, specific leaf area, leaf thickness, leaf dry matter content, chlorophyll content, nitrogen content, phosphorus content, C:N, C:P, vein density, and vein diameter varied significantly across altitudes. Mean annual temperature and total radiation explained 42.1% and 16.2% of leaf-trait variation, respectively. They served as key environmental factors driving the altitudinal variation in leaf traits. Mean annual temperature exhibited the greatest influence on leaf area ( R 2 =0.73), and total radiation exerted the most prominent effect on leaf thickness ( R 2 =0.72). Both relationships were significantly positive. D. macropodum exhibited low leaf nitrogen and phosphorus at the low altitude of 1100 m, and the overall and local trait networks were loose, adopting a conservative resource strategy. At the medium altitude of 1500 m, leaf nutrient contents were relatively high. The overall network of leaf traits was tightly connected and local network was loose. By enhancing the dependency among leaf traits, and improving phosphorus utilization efficiency, D. macropodum could cope with competition in deciduous forests and adopt resource acquisition strategies. Further, at the highest altitude of 1900 m, D. macropodum had relatively large leaf thickness, chlorophyll content, and leaf dry matter content, but relatively small leaf area. The local network connections were tight while the overall network looseness, indicating a resource conserving strategy. The trade-off relationship between C:P and leaf phosphorus content was closely related to phosphorus use efficiency, and its variation was an important indicator for identifying life strategies of D. macropodum in different altitudes.

Purpose: Our previous studies have found that Stathmin, a microtubule depolymerizing protein, is a potential biomarker to guide locally advanced oral squamous cell carcinoma (OSCC) induction chemotherapy. This study further explored the regulatory effect of vincristine on Stathmin and its potention as an alternative chemotherapy drug., Methods: Stathmin overexpressed and knockdown stable cell lines were constructed. Cell proliferation, q-PCR, Western blot, subcutaneous xenograft and other experimental methods were used to value the regulatory effect of vincristine on Stathmin. The differences were statistically analyzed with SPSS 23.0 software package., Results: Vincristine inhibited the expression of Stathmin in OSCC cell lines. The sensitivity to vincristine was increased in Stathmin overexpressed OSCC cell lines. Vincristine had potent anti-tumor effect for OSCC cell line xenografts with higher Stathmin expression., Conclusions: Vincristine is a potential alternative chemotherapeutic agent for OSCC with higher Stathmin expression.

To compare the accuracy of SHA.LIN,S.T.O.N.E.nephrolithometry scoring system,and Clinical Research Office of the Endourological Society(CROES)nephrolithometry nomogram in predicting percutaneous nephrolithotomy(PCNL)outcomes including stone free rate(SFR)and perioperative status. Methods The clinical data of 90 patients with nephrolithiasis undergoing PCNL in department of urology,China-Japan Friendship Hospital from January 2015 to March 2018 were retrospectively analyzed.The general data,stone characteristics,operation approaches,and perioperative variables were recorded.SHA.LIN,S.T.O.N.E.score,and CROES nomogram were assigned according to the computed tomography(CT)findings before surgery.Stone free status was evaluated by kidney-ureter-bladder one month after PCNL.The relationships of SHA.LIN score,S.T.O.N.E.score,and CROES score with SFR,postoperative complications,operation time(OT),length of hospital stay(LOS),estimated blood loss(EBL),and decrease of hemoglobin was evaluated.Receiver operating characteristic(ROC)curves were used to analyze the predictive accuracy. Results The SFR was 72.2%(65/90)and postoperative complications occurred in 33 cases(36.7%).The mean OT was(103.1±39.6)min,the mean EBL was(46.1±53.0)ml,the mean LOS was(15.3±5.2)d,the mean postoperative LOS was(8.5±3.4)d,and the mean decrease of hemoglobin was(16.1±10.2)g/L.Stone-free patients had significantly lower SHA.LIN score(8.23 vs. 10.36, P =0.000)and S.T.O.N.E.score(7.05 vs. 8.16, P =0.000)and significantly higher CROES score(188.50 vs. 143.89, P =0.000)compared to patients with residual fragments.All these scores were not significantly associated with complications( P >0.05).On the other hand,all these scores were significantly correlated with OT,EBL,and decrease of hemoglobin(SHA.LIN: P OT =0.006, P EBL =0.028, P decrease of hemoglobin =0.014;S.T.O.N.E.: P OT =0.012, P EBL =0.047, P decrease of hemoglobin =0.011;and CROES: P OT =0.040, P EBL =0.045, P decrease of hemoglobin =0.013).SHA.LIN( P =0.001)and S.T.O.N.E.( P =0.005)scores were associated with LOS.Logistic regression analysis revealed that SHA.LIN( OR =2.491),S.T.O.N.E.( OR =3.030),and CROES( OR =0.973)scores were significantly associated with stone-free status.ROC curves in predicting SFR showed that there was significant difference in the areas under the curves(AUC)for the SHA.LIN vs. S.T.O.N.E.score [0.808(95% CI =0.711-0.905) vs. 0.748(95% CI =0.632-0.864), P =0.047].AUC for the CROES score [0.770(95% CI =0.664-0.877)] showed no significantly different for the SHA.LIN score or the S.T.O.N.E.score( P >0.05). Conclusions All these three scoring systems have good predictive accuracy for SFR.SHA.LIN is more precise than S.T.O.N.E.in predicting SFR.However,they can not predict postoperative complications.

Three typical plant communities (evergreen broad-leaved forest at low-altitude 1100 m, evergreen and deciduous mixed broad-leaved forest at mid-altitude 1500 m, and evergreen conife-rous and broad-leaved mixed forest at high-altitude 1900 m) in Maoer Mountain, Guangxi, China were surveyed along an altitude gradient. We measured the tree layer plant architecture and environmental factors, to analyze the variation of plant architecture traits among the three communities and its influencing factors. The results showed that the tree layer canopy area, basal diameter at 45 cm height, diameter at breast height (DBH), and leaf convergence increased with increasing altitude, whereas tree height, branch height, and canopy thickness first increased and then decreased. Horizontal branches occurred more often in communities at lower altitude , less frequent at high altitude, and the least frequent in middle altitude communities. Correlations among tree layer plant architecture traits were stronger in the mid-altitude community than that in the other altitude communities. Results from the redundancy analysis showed that soil organic matter and total solar radiation were the main factors driving the variation of plant architecture traits in the tree layers, accounting for 39.6% and 23.9% of the total variation, respectively. Soil organic matter had a greater positive impact on canopy area and branch height, whereas total solar radiation was more influential on the DBH and 45 cm basal diameter. In conclusion, tree layer architecture of communities along the altitude gradient in Maoer Mountain was divergent, with soil organic matter and total solar radiation as the main driving forces.

Objective: To explore the maintaining measures for the vitality of hematopoietic stem cells (HSC) in vitro, so as provide technical support for ultra long distance transport of HSC collected from unrelated donors., Methods: Peripheral blood hematopoietic stem cells (PBHSC) were treated by different methods according to various groups, then stored at 4 ℃ in the refrigerator. The percentage of CD34 + cells, relative cell activity, relative cell proliferation rate, relative colony-forming rate, oxygen fraction and intracellular reactive oxygen species (ROS) were detected at 0, 24, 48 and 72 h after storage of PBHSC respectively., Results: The percentage of CD34 + cells during 72 h storage did not altered. Along with the prolonging of storage time, the relative cell activity, relative cell proliferation rate and relative colony-forming rate gradually decreased in untreated PBHSC(control group), the related coefficients were -0.796, -0.883 and -0.815 respectively. Plasma dilution, antioxidants and oxygenation could improve the relative cell activity and relative cell proliferation rate, but oxygenation could decrease the relative colony-forming rate of PBHSC. The combination of 2 or 3 factors showed stronger protection effects on PBHSC. The intracellular level of ROS decreased gradually with the prolonging of storage time. Oxygenation of PBHSC could increase oxygen fraction, and also increase the intracellular level of ROS at the same time. The addition of antioxidants could reduce the level of ROS., Conclusion: The percentage of CD34 + cells can not serve as the indicator of PBHSC vitality. Plasma dilution, oxygenation and antioxidants can increase the survival and viability of PBHSC, but oxygenation can increase the intracellular ROS level and impair colony-forming ability of PBHSC. The combination of multiple factors can maintain the vitality of PBHSC better.

Objective: To study the blood flow parameters for 2 anatomical segments of posterior cerebral artery (PCA) in normal singleton fetal.
 Methods: The blood flow velocity parameters peak systolic velocity (PSV), end diastolic velocity (EDV), time-average maximum velocity (TAMAXV), velocity time integral (VTI) and resistance parameters systolic peak velocity and end diastolic velocity ratio (S/D), pulsatility index (PI), resistance index (RI) for 2 anatomical segments in PCA were recorded. The first segment of the PCA (PCAS1) was recorded between the origin of PCA and the proximal part of the posterior communicating artery. The second segment of the PCA (PCAS2) was recorded at the distal part of the posterior communicating artery. The blood parameters in both PCAS1 and PCAS2 were analyzed by using Pearson correlation and multiple curves fitting with gestational age (GA). Paired student's t test was performed to compare the difference in blood parameter between PCAS1 and PCAS2.
 Results: The blood flow velocity parameters in both PCAS1 and PCAS2 were increased with the GA (P<0.0001), with the best fitted curves of Quadratic curve (P<0.0001). There were no correlations between resistance parameters in PCA and GA (P>0.05). Resistance parameters in PCAS1 were higher than those in PCAS2 (P<0.05).
 Conclusion: The blood flow velocity parameters in both PCAS1 and PCAS2 are increased with GA. The resistance parameters in both PCAS1 and PCAS2 do not change with GA. Study on the velocities and resistance in these 3 arterial branches provides a more comprehensive evaluation on the process of brain circulation.

Objective: To understand the transmission mode of human infection with avian influenza A (H7N9) virus., Methods: Field epidemiological investigation was conducted for a family clustering of human infection with H7N9 virus in Hengxian county, Guangxi Zhuang Autonomous Region in February 2014. Two patients and their 82 close contacts were surveyed. The samples collected from the patients, environments and poultry were tested by using real time reverse transcriptase-polymerase chain reaction (rRT-PCR), and the samples from patients were used for virus isolation. The samples from 5 close contacts were tested with RT-PCR. The clinical data, exposure histories of the patients and the detection results of the isolates and their homology were analyzed., Results: Patient A became ill 4 days after her last exposure to poultry in Zhongshan, Guangdong province, and returned to her hometown in Hengxian 2 days after onset. Patient B was patient A's 5 years old son, who had no known exposure to poultry but slept with patient A for 4 days. He developed symptoms 4 days after last contact with his mother. Two strains of H7N9 virus were isolated from the two patients. The 2 isolates were highly homogenous (almost 100%) indicated by gene sequencing and phylogenetic tree. None of the other 81 close contacts developed symptoms of H7N9 virus infection., Conclusion: Patients B was infected through close contact with patient A, indicating that avian H7N9 virus can spread from person to person, but the transmissibility is limited and non-sustainable.

Objective: To assess qualities on methodologies and reporting on Meta-analysis used in papers being published in National Medical Journal of China., Methods: Computerized literature searching was performed in Wangfang Medical Online to collect articles that Meta-analysis was used in the National Medical Journal of China since January 1998 until October 2014. Manual retrieval was also conducted.Qualities on methodologies and reporting were evaluated by both Assessment of Multiple Systematic Reviews (AMSTAR) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) scales., Results: A total of 74 papers were included. The results on the qualities of methodology evaluation in these papers were 3 to 10 (median 7) scores, 10 articles (13.5%) were rated as high, 61 articles (82.4%) as moderate and 3 articles (4.1%) as low. No statistically significant difference existed in each year of AMSTAR score (χ(2) = 10.205, P = 0.423). The titles of AMSTAR scales with a lower coincidence rate were "Was a list of studies (included and excluded) provided?", "Was the conflict of interest stated?", "Was the status of publication (i.e.grey literature) used as an inclusion criterion?" and "Was the likelihood of publication bias assessed?". The results on the qualities of reporting evaluation in these papers were 5.5 to 26 (median 20) scores, 9 articles (12.2%) scored <15 points, 39 articles (52.7%) 15.5-21 points and 26 articles (35.1%) 21.5-27 points. There was statistically significant difference in each year of PRISMA score (F = 4.301, P = 0.000). And the year 2010 was the highest one. The titles of PRISMA scales with a lack of comprehensive reports were "Structured summary", "Objectives of introduction", "Protocol & registration", "Data collection process", "Data items", "Risk of bias in individual studies", "Risk of bias across studies", "Additional analyses", "Study selection","Risk of bias within studies", "Conclusion limitations", "Conclusions" and "Funding support" etc., Conclusions: Articles of Meta-analysis published in National Medical Journal of China have a high quality so as to provide rationales for clinical decision-making. However, both of qualities on methodology and reports sill call for continual improvements.

Objective: To assess the methodological quality and reporting quality on Meta-analysis being published in the Chinese Journal of Gastrointestinal Surgery., Methods: Computerized literature searching was carried out in Wanfang Medical Online to collect articles that Meta-analysis was used in the Chinese Journal of Gastrointestinal Surgery since it was founded till July, 2014. Manual retrieval was also conducted. Two researchers independently screened for literature and extracted data. Qualities on methodologies or on the processes of reporting and reviewing were evaluated by both AMSTAR and PRISMA scales., Results: Forty-two papers on meta-analyses were included in this study. Results on the quality of methodology evaluation showed that the lowest and highest scores were 6 and 9 respectively, the median score was 7. Two articles (4.8%) were rated as high, 40 articles (95.2%) as moderate and 0 articles (0%) as low. Although the quality of methodology was above the average, however, there were still some problems seen in some papers as the conflict of interest was not stated, the list of studies (included and excluded) was not provided, a comprehensive literature search was not performed, the likelihood of publication bias was not assessed, etc. Results on the quality of reporting evaluation showed that the lowest and highest scores were 14 and 22 respectively, the average score was 18.43 ± 2.03, 3 articles (7.1%) scored less than 15 points, 35 articles (83.3%) scored 15.5-21 points, and 4 articles (9.6%) scored 21.5-27 points. The included reviews had high quality on the titles of the report, inclusion criteria, rationale of introduction, synthesis of results, results of individual. However, the abstract, objectives of introduction, scheme and registered, inclusion criteria, research screening, additional analysis, conclusion limitations, funding support etc. were lack of comprehensive reports., Conclusions: Articles on Meta-analysis published in the Chinese Journal of Gastrointestinal Surgery are of high quality. The Chinese Journal of Gastrointestinal Surgery can provide better evidence for clinical decision to gastrointestinal surgeons. However, both of qualities on methodology and reports sill call for continuous improvement.

Covariance analysis, curve-fitting, and canonical correspondence analysis (CCA) were used to explore the effects of topographic factors on the plant diversity and distribution patterns of ground flora with different growth forms in the karst mountains of Southwest Guangxi, China. A total of 152 ground plants were recorded. Among them, 37 species were ferns, 44 species herbs, 9 species lianas, and 62 species shrubs. Covariance analysis revealed that altitude significantly correlated with the individual number and richness of ground plants, and slope aspect had a significant effect on richness. Statistical analyses showed a highly significant nonlinear correlation between the individual number or richness of ground plants and altitude. Results of CCA revealed that slope aspect had a significant effect on the distribution pattern of ferns, and slope had a significant effect on the distribution patterns of herbs, lianas and shrubs. Ferns were more sensitive than herbs, lianas and shrubs to changes in heat and soil water caused by aspect. The effect of slope was stronger than that of elevation on soil water and nutrients, and it was the most important topographic factor that affected the distribution patterns of herbs, lianas and shrubs in this region.

Objective: To evaluate the cardiac function of fetuses with intrauterine growth retardation (IUGR) by using tissue Doppler imaging (TDI)., Methods: Peak velocity in early (E) and late (A) diastole were measured by pulsed-wave Doppler, and the peak annular velocities in systole (S'), early (E') and late (A') diastole were measured by TDI. Isovolumetric contraction time (ICT), ejection time (ET), isovolumetric relaxation time (IRT) were recorded. The ratios E/A, E'/A', E/E', E/(E'× S') and myocardial performance index (MPI) were calculated., Results: Compared with the control group, E', A', S' and E'/A' were obviously lower (P<0.05) while E/E', E/(E'× S') and MPI were obviously higher (P<0.05) in the IUGR group; although E, A and E/A were slight lower in the IUGR group, the change was not significant (P>0.05)., Conclusion: Both diastolic and systolic heart function were jeopardized in IUGR fetuses.

In order to study the function of soil microfauna and its responses to environmental changes, we used metagenome analyses of the 18S rDNA gene region to identify differences in microfauna diversity and community structure among fifteen soil samples belonging to five different Cunninghamia lanceolate plantations. The plantations were located in Youxian County, Hunan Province in central China. The trees in these plantations were of different ages (3, 13, and 26 years) and belonged to different ecological successions (first, second, and third successions). The total dataset comprised 94922 high quality sequences with an average length of 436 bp. The dominant taxonomic groups across all samples were Chordata, Annelida, Arthropoda, Nematoda, Rotifera and Platyhelminthes with each accounting for 60.8%, 24.0%, 7.4%, 3.6%, 1.5% and 1.2% of the sequences, respectively. There were significant differences in ACE index and Shannon index among the five plantations. The lowest diversity of soil microfauna was in the 13-year old plantation of the first ecological succession. The correlation analysis showed that both ACE and available potassium concentration were negatively correlated to the Chaol index. However, there were no significant correlations between the Shannon, Simpson indices and the physical-chemical properties of soil. Overall, the Jaccard's similarity coefficient was less than 0.4 among samples at each site, and significant differences were found among plantations.

The immobilized polysaccharide-based chiral stationary phase has attracted considerable attention over the past decades due to its high chemical stability, good solvent resistance, great enantioseparation ability, etc. In this study, a new immobilized cellulose chiral stationary phase (denoted as ImCel) was prepared through the Staudinger reaction of 6-azido-6-deoxy-cellulose-3,5-dichlorophenylcarbamate and aminopropyl silica gel. The enantioseparation performance of the ImCel for 20 pairs of chiral analytes and the effect of non-standard solvents have been investigated by high performance liquid chromatography. Baseline separations of 17 pairs of enantiomers were achieved on the ImCel. The separation ability of the ImCel in the normal mode was much better than in reversed mode. In addition, the ImCel showed good chemical stability in the non-standard mobile phase due to the covalent bonds between the cellulose chiral selectors and silica support. Moreover, it exhibited complementarity with another immobilized-cellulose chiral stationary phase containing 3, 5-dimethylphenylcarbamate groups for the separation of a series of 9-fluorenylmethyloxycarbonyl (fmoc) -derived amino acids. The reversal of enantiomer elution order induced by the difference of the substituents in chiral stationary phase was observed under the same chromatographic conditions. In brief, a new immobilized cellulose chiral stationary phase with high stability and good separation performance was developed in this work.

The crude extracts of the fermentation broth from a marine sediment-derived actinomycete strain, Saccharothrix sp. 10-10, showed significant antibacterial activities against drug-resistant pathogens. A genome-mining PCR-based experiment targeting the genes encoding key enzymes involved in the biosynthesis of secondary metabolites indicated that the strain 10-10 showed the potential to produce tetracenomycin-like compounds. Further chemical investigation of the cultures of this strain led to the identification of two antibiotics, including a tetracenomycin (Tcm) analogs, Tcm X (1), and a tomaymycin derivative, oxotomaymycin (2). Their structures were identified by spectroscopic data analysis, including UV, 1D-NMR, 2D-NMR and MS spectra. Tcm X (1) showed moderate antibacterial activities against a number of drug-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) pathogens, with the MIC values in the range of 32-64 microg x mL(-1). In addition, 1 also displayed significant cytotoxic activities against human cancer cell lines, including HL60 (leukemia), HepG2 (liver), and MCF-7 (breast) with the IC 50 values of 5.1, 9.7 and 18.0 micromol x L(-1), respectively. Guided by the PCR-based gene sequence analysis, Tcm X (1) and oxotomaymycin (2) were identified from the genus of Saccharothrix and their 13C NMR data were correctly assigned on the basis of 2D NMR spectroscopic data analysis for the first time.

In the last decade, along with the development of taxonomy research in marine-derived actinobacteria, more and more halogenated natural products were discovered from marine actinobacteria. Most of them showed good biological activity and unique structure compared to those from land. The special halogenation mechanism in some compounds' biosynthesis has drawn great attention. So in this review, we focus on the halogenated natural products from marine actinobacteria and their halogenation mechanisms.

Objective: To obtain a specific antagonist of CXCR4, SDF-1P2G54 by mutating SDF-1 second proline (P) into glycin (G) and removing the α-helix of its C-terminal., Methods: SDF-1p2g54 gene amplified by PCR was inserted into the vector pET-30a (+) and transformed into Escherichia coli (E. coli) strain BL21. After IPTG induction of E. coli, the expressed recombinant protein was purified with nickel-affinity chromatography column under denaturing conditions and refolded with gradient dilution and ultra-filtration. The chemotactic effect of SDF-1P2G54 on Jurkat cells and its antagonistic effect against SDF-1 were determined by transwell assay; flow cytometry was used to assay the ability of SDF-1P2G54 to induce calcium influx and CXCR4 internalization in MOLT4 cells., Results: The recombinant protein SDF-1P2G54 completely lost the functions to activate CXCR4 or to induce transmembrane migration of Jurkat cells and calcium influx in MOLT4 cells, but maintained a high affinity to CXCR4. SDF-1P2G54 effectively inhibited the chemotactic effect of wild-type SDF-1 to Jurkat cells, and induced rapid CXCR4 internalization in MOLT4 cells., Conclusion: SDF-1P2G54 is a new antagonist of CXCR4 with a potential value as an effective inhibitor of HIV-1 infection, cancer metastasis or other major diseases.

Objective: To estimate disease burden and epidemiological characteristics of acute meningitis/encephalitis, and provide the basis for the disease control strategy development., Methods: A syndrome surveillance system was established in Guigang city with a population of 5 020 000. For the suspected cases, serum and CSF were collected, and bacterial culture, latex agglutination test, real-time PCR and ELISA tests were carried out. All involved cases were identified to 6 categories according to WHO case definition., Results: 1424 suspected cases were evaluated in a surveillance of 30 months, yielding the incidence, mortality and mortality of 11.35/100 000 (1424/12 546 500 person years), 0.43/100 000 (54/12 546 500 person years), 3.79% (54/1424) respectively. A total of 103 and 51 cases were confirmed for JE, bacterial meningitis, with a incidence of 0.82/100 000 (103/12 546 500 person years), 0.41/100 000 (51/12 546 500 person years). 96.10% (99/103) of JE cases and 37.30% (19/51) bacterial meningitis cases occurred in < 10 years old children and < 5 years old children. A clinical misdiagnosis rate of 19.42% (20/103) and 15.69% (8/51) were observed for JE and bacterial meningitis., Conclusion: Acute encephalitis, meningitis syndrome can cause a higher burden of disease, of which the main components of viral encephalitis. Most of syndrome is occurred in summer and autumn, mainly reported in children of younger than 10 years old. A quite misdiagnosis would be made among meningitis and encephalitis syndrome cases.

Objective: To investigate the effect of bicyclol on vascular oxidative stress injury induced by superoxide anion., Methods: Rat thoracic aortic rings were isolated for isometric tension recording using organ bath technique. Superoxide arterial injury was induced by pyrogallol exposure, and the effect of bicyclol on endothelium-dependent relaxation was evaluated., Results: Bicyclol (10(-8) - 10(-5) mol/L) relaxed endothelium-intact aortic rings precontracted by phenylephrine. This effect was abolished by L-NAME, an inhibitor of nitric oxide synthase and indomethacin, an inhibitor of cyclooxygenase. Exposure to pyrogallol (500 micromol/L) resulted in decrease of acetylcholine(ACh)-induced endothelium-dependent relaxation in aortic rings, and pre-incubation of bicyclol (10(-5) mol/L) for 45 min improved the relaxation attenuated by pyrogallol. In aortic rings pre-treated with indomethacin, bicyclol increased the ACh-induced relaxation that was inhibited by pyrogallol (500 micromol/L). This effect was not found in aortic rings pre-treated with L-NAME., Conclusion: Bicyclol has endothelium-dependent vasodilating effect on rat thoracic aorta and improves vascular function by attenuating oxidative stress. Nitric oxide from endothelium is involved in the anti-oxidative effect of bicyclol.

Objective: To study the diversity of culturable actinomycetes isolated from the sea deposit of Tiger beach at Bohai bay, Dalian, China., Methods: By using five different media strains we isolated actinomycetes strains from the sea deposit of Tiger beach at Bohai bay, Dalian, China. Partial 16S rRNA sequences were carried out to characterize the diversity of culturable actinomycetes., Results: A total of 1215 colonies with phenotypical actinomycetes were isolated, of which 271 were classified by 16S rRNA phylogenetic analysis. The data showed that 251 strains were homologous with Actinobacteria (92.26% ) including 15 genera of 11 families, and the remaining 20 strains were possible members of the phylum Firmicutes and Proteobacteria. There were 7 strains (3-166, 3-117, 3-435, 5-186-2, 5-9, 5-171, 3-134) to be preliminarily identified as unreported species., Conclusion: A high diversity of culturable actinomycets both in terms of the number of species and phylogenetic composition was presented from the sea deposit of Tiger beach in Bohai bay.