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1Therapeutic effects of the artemisinin analog SM934 on lupus-prone MRLIIpr mice via inhibition of TLR-triggered B-cell activation and plasma cell formation显示文摘我们以前报导了那 SM934,水溶性的 artemisinin 衍生物,是在鼠科的豺狼座模型的一个可行处理。在当前的学习,我们进一步在豺狼座容易的 MRL/lpr 老鼠上调查了 SM934 的修改剂量政体的治疗学的效果并且在 B 房间回答上探索了它的效果,在全身的豺狼座 erythematosus (SLE ) 的一个中央病原的事件。当口头上地管理了时两次每日, SM934 显著地延长了 MRL/lpr 老鼠的寿命,改善 lymphadenopathy 症状并且减少浆液的层次反原子的抗体(言论集) 并且病原的 cytokines IL-6, IL-10 和 IL-21。而且, SM934 处理由增加静止 B 房间数字在 MRL/lpr 老鼠的怒气恢复了 B 房间分隔空间,维持幼芽的中心 B 房间数字,减少激活的 B 房间数字和减少的血浆房间(PC ) 数字。前 vivo, SM934 压制了触发的像使用费的受体(TLR ) B 房间的激活和增长,以及抗体分泌物。而且,现在的学习证明 SM934 由 downregulating TLR7/9 mRNA 表示, MyD88 蛋白质表示和 NF-κ 防碍 B 房间内在的小径; B phosphorylation。在人的外部血 mononuclear 房间(PBMC ) ,与在 MRL/lpr 鼠标的结果一致, SM934 禁止了联系 TLR 的 B 房间激活和 PC 区别。在结论, SM934 的两次每日的 dosing 政体由压制 B 房间激活和血浆房间形成在豺狼座容易的 MRL/lpr 老鼠上有治疗学的效果。Yanwei Wu Shijun He Bingxin Bai Luyao Zhang Lu Xue Zemin Lin Xiaoqian Yang Fenghua Zhu Peilan He Wei Tang Jianping Zuo 2016Cellular & Molecular Immunology2016,13,3:31
2Microstructure,mechanical and corrosion properties of Mg-2Dy-xZn(x=0,0.1,0.5 and 1 at.%)alloys显示文摘Microstructure,mechanical and corrosion properties of as-cast Mg-2Dy-xZn(x=0,0.1,0.5,and 1)(at.%)alloys were investigated.The microstructures of the as-cast Mg-2Dy and Mg-2Dy-0.1Zn alloys mainly consisted ofα-Mg phase and Mg_(24)Dy_(5)eutectic phase.With 0.5 at.%Zn addition,Mg_(12)ZnDy phase with 18R-type long period stacking ordered(LPSO)structure and Mg_(2)Dy phase precipitated at the grain boundaries.When the content of Zn is 1 at.%,only the Mg_(3)Zn_(3)Dy_(2)phase formed in theα-Mg matrix.The electrochemical measurements and immersion testing results indicated that the Mg-2Dy-0.1Zn alloy exhibited the best corrosion resistance.It revealed that the morphology,scale,amount and distribution of the second phase have a great effect on the corrosion resistance of alloy.Additionally,the tensile testing results showed that the Mg-2Dy-0.5Zn alloy exhibited the higher tensile strength and good elongation,especially at 200℃.The improvement of mechanical properties was mainly due to the strengthening of LPSO phase and grain refinement of α-Mg.Guangli Bi Yuandong Li Shijun Zang Jianbin Zhang Ying Ma Yuan Hao 2014Journal of Magnesium and Alloys2014,2,1:13
3Association of KIR Genotypes and Haplotypes with Susceptibility to Chronic Hepatitis B Virus Infection in Chinese Han Population显示文摘Killer immunoglobulin-like receptor (KIR) genes can regulate the activation of NK and T cells upon interaction with HLA class I molecules. Hepatitis B virus (HBV) infection has been regarded as a multi-factorial disorder disease. Previous studies revealed that KIRs were involved in HCV and HIV infection or clearance. The aim of this study was to explore the possibility of the inheritance of KIR genotypes and haplotypes as a candidate for susceptibility to persistent HBV infection or HBV clearance. The sequence specific primer polymerase chain reaction (SSP-PCR) was employed to identify the KIR genes and pseudogenes in 150 chronic hepatitis B (CHB) patients, 251 spontaneously recovered (SR) controls, and 412 healthy controls. The frequencies of genotype G, M, FZ1 increased in CHB patients compared with healthy control subjects. The frequency of genotype AH was higher in SR controls than that in both CHB patients and healthy controls. The carriage frequencies of genotype G and AH were higher; while, the frequencies of AF and AJ were lower in SR controls than those in healthy control subjects. The frequency of A haplotype was lower, whereas, the frequency of B haplotype was higher in CHB patients and SR controls than those in healthy controls. In healthy controls, haplotype 4 was found lower compared with that in CHB patients and SR controls and the frequency of haplotype 5 was higher in SR controls than that in other two groups. Based on these findings, it seems that the genotypes M and FZ1 are HBV susceptive genotypes; AH, on the other hand, may be protective genotypes that facilitate the clearance of HBV. It appears that the haplotype 4 is HBV susceptive haplotype, whereas, haplotype 5 may be the protective haplotype that facilitates the clearance of HBV.Zhiming Lu Bingchang Zhang Shijun Chen Zhongtao Gai Zhaolei Feng Xiangdong Liu Yiqing Liu Xin Wen Li Li Yulian Jiao Chunyan Ma Song Shao Xiangfa Cui Guojian Chen Jianfeng Li Yneran Zhao 2008Cellular & Molecular Immunology2008,5,6:13
4Xingxueanthus: An Enigmatic Jurassic Seed Plant and Its Implications for the Origin of Angiospermy显示文摘The origin of angiosperms has been tantalizing botanists for centuries. Despite the efforts of palaeobotanists, most of the pre-Cretaceous angiosperms are regarded either non-convincing or misdated. The applications of SEM and LM (light microscope) enable us to recognize a coalified fossil plant, Xingxueanthus sinensis gen. et sp. nov., from the Haifanggou Formation (Middle Jurassic, >160 Ma) in western Liaoning, China. Xingxueanthus is an 'inflorescence' with more than 20 female units spirally arranged. Each female unit is situated in the axil of a bract. The female unit is composed of an ovule-container and a style-like projection at the top. There is a vertical column bearing several ovules in the ovule-container. The general morphology and the internal structure of Xingxueanthus distinguish itself from any known fossil and extant gymnosperms, and its structures are more comparable to those of angiosperms. Xingxueanthus, if taken as a gymnosperm, would represent a new class, demonstrate an evolutionarily advanced status of ovule-protection in gymnosperms never seen before, and provide new insights into the origin of angiospermy. Alternatively, if taken as an angiosperm, together with Schmeissneria, it would increase the diversity of Jurassic angiosperms, which has been underestimated for a long time, and suggest a much earlier origin of angiospermy than currently accepted.WANG Xin WANG Shijun 2010Acta Geologica Sinica(English Edition)2010,84,1:13
5Jianpijiedu Fang improves survival of hepatocarcinoma mice by affecting phosphatase and tensin homolog, phosphoinositide 3-kinase, and focal adhesion kinase显示文摘OBJECTIVE: To investigate the effect of Jianpijiedu Fang (JPJDF) on phosphatase and tensin homolog (PTEN), phosphoinositide 3-kinase (PI3K), and focal adhesion kinase (FAK), and on the survival of hepatocellular carcinoma (HCC) nude mice. METHODS: Forty male nude mice were randomly divided into 4 groups. Human HCC tissue was implanted in the livers of three groups. After 24 h, the three groups were treated respectively with JPJDF (37.5 g/kg), saline (20 mL/kg) and Tegafur (FT-207, 160 mg/kg) once a day for 10 weeks. The control group without implanting the tissue was concurrently treated with saline (20 mL/kg). The survival data and body weight of all mice were recorded, and expression levels of PTEN, PI3K and FAK in normal tissue and cancer tissue of the livers were eval-uated with immunohistochemical method. RESULTS: The cumulative survival rate of the mice in the JPJDF group was higher than those of the other groups. The rate of weight loss was the lowest in JPJDF group. The survivability and weight loss rate in FT-207 group were the poorest in all groups. The expression intensity of PTEN was higher in normal tissues than in cancer tissues, and lower in the normal tissues of HCC models than in that of mice without HCC. The PTEN expression intensity in normal tissue and cancer tissue from mice treated with FT-207 were lower than that from the mice treated with JPJDF or saline.The expression intensity of PI3K was higher in cancer tissue than in normal tissue. The PI3K expression intensity was the lowest in normal tissue and cancer tissue from mice treated with JPJDF, and the intensity from mice treated with FT-207 was the highest. In mice treated with JPJDF, the expression intensity of FAK was higher in the normal tissue and lower in the cancer tissue than those of the other treatment groups. CONCLUSION: The mechanism accounting for the prolonged survival of HCC-bearing mice treated with JPJDF might be related to the reduction in weight loss and the benign regulation of PTEN, PI3K, and FAK.Baoguo Sun Jun Meng Ting Xiang Zexiong Chen Yulong Li Lisha Lu Shijun Zhang Xiaolin Chen 2013Journal of Traditional Chinese Medicine2013,33,4:12
6Surrounding rock control mechanism of deep coal roadways and its application显示文摘Aiming at the surrounding rock control problem of mining and preparation entries in Xingdong mine with large mining depth, and the comprehensive control countermeasures including high pre-stress cable truss system, this study put forward powerful anchor support system and anchor cable adaption technology to surrounding rock deformation. Furthermore, the control measures possess the supporting performance with ‘‘primary rigid-following flexible-new rigid, and primary resistance-following yield-new resistance'', which suits deep roadway surrounding rock control. The mechanical model of truss anchor supporting roof beams was established, and the inverted arch deflection produced by the cable pre-stress with stress increment effect and roof beam deflection were obtained. And then the system working mechanism was illustrated. Finally, the surrounding rock support parameters were determined by means of comprehensive methods, and put into practice. The results show that surrounding rock deformation realized secondary stability after three months. The roadway sides convergence value was less than 245mm, and roof subsidence was less than 124mm. In addition, there was no expansion and renovation during service period.Xie Shengrong Li Erpeng Li Shijun Wang Jinguang He Chongchong Yang Yafeng 2015International Journal of Mining Science and Technology2015,25,3:10
7Hybrid PdAg alloy-Au nanorods: Controlled growth, optical properties and electrochemical catalysis显示文摘高质量的混合 nanostructures 的可控制的生长为层次、复杂、多功能的设备的制造是高度合乎需要的。这里, PdAg 合金在金 nanorods 上的不同地点是 controllably 成年的,生产有在金牌的结束的 PdAg 的像哑铃的 nanostructures 有种的 PdAg 的 nanorods 或分叉的 nanostructures 对金 nanorods 几乎垂直。金 nanorods 上的 PdAg 合金的成核地点能被改变 H2PdCl4, AgNO3 和 cetyltrimethylammonium 溴化物(CTAB ) 的集中有效地调节。像哑铃、分叉的 nanostructures 被传播描绘电子显微镜学(TEM ) ,高分辨率的 TEM (HRTEM ) ,扫描线的精力散的 X 光检查光谱学(版本) , X 光检查光电子光谱学(XPS ) 和紫外力的吸收光谱学。他们的 electrocatalytic 表演作为探查反应用乙醇氧化被评估。像哑铃的 nanostructures 比分叉的显示出更好毒害反的表演,而是一项更坏的电气化学的活动。结果为基本研究或潜在的应用为复杂 nanostructures 的控制生长提供指南。Qiao Zhang Xia Guo Zhenxing Liang Jianhuang Zeng Jian Yang Shijun Liao 2013Nano Research2013,6,8:10
8Single-Atom Catalysts for Electrochemical Hydrogen Evolution Reaction: Recent Advances and Future Perspectives显示文摘Hydrogen,a renewable and outstanding energy carrier with zero carbon dioxide emission,is regarded as the best alternative to fossil fuels.The most preferred route to large-scale production of hydrogen is by water electrolysis from the intermittent sources(e.g.,wind,solar,hydro,and tidal energy).However,the efficiency of water electrolysis is very much dependent on the activity of electrocatalysts.Thus,designing high-effective,stable,and cheap materials for hydrogen evolution reaction(HER)could have a substantial impact on renewable energy technologies.Recently,single-atom catalysts(SACs)have emerged as a new frontier in catalysis science,because SACs have maximum atom-utilization efficiency and excellent catalytic reaction activity.Various synthesis methods and analytical techniques have been adopted to prepare and characterize these SACs.In this review,we discuss recent progress on SACs synthesis,characterization methods,and their catalytic applications.Particularly,we highlight their unique electrochemical characteristics toward HER.Finally,the current key challenges in SACs for HER are pointed out and some potential directions are proposed as well.Zonghua Pu Ibrahim Saana Amiinu Ruilin Cheng Pengyan Wang Chengtian Zhang Shichun Mu Weiyue Zhao Fengmei Su Gaixia Zhang Shijun Liao Shuhui Sun 2020Nano-Micro Letters2020,12,2:10
9Modeling cavitation flow of cryogenic fluids with thermodynamic phase-change theory显示文摘Cavitation is the formation of vapor bubbles within a liquid where the flow dynamics causes the local static pressure to drop below the vapor pressure. The so-called full cavitation model (FCM) developed by Singhal has been widely used in numerical modeling of the cavitation flow for thermosensible and non-thermosensible fluids. Within the FCM, the bubble size is taken to be equivalent to the maximum possible value to forego the calculation of bubble number density. We developed a new cavitation model by recalculating the bubble radius in FCM to account for the effects of local pressure. The new model was obtained by combining the thermodynamic phase-change theory and the Young-Laplace equation with the assumption of thermodynamic equilibrium during the cavitation process. The cavitation calculations were performed based on the mathematical framework of the homogeneous equilibrium flow model and the transport-equation-based model for vapor phase mass fraction. The model was validated by modeling the cavitating flow of liquid nitrogen and liquid hydrogen through NASA hydrofoil and Ogive with consideration of the phase-change thermal effects. The temperature and pressure distributions with the new model are found to agree well with data from existing experimental studies, as well as the simulations with the FCM.ZHANG XiaoBin WU Zhao XIANG ShiJun QIU LiMin 2013Chinese Science Bulletin2013,58,4:9
10Mortality outcomes of low-dose computed tomography screening for lung cancer in urban China:a decision analysis and implications for practice显示文摘Background: Mortality outcomes in trials of low-dose computed tomography(CT) screening for lung cancer are inconsistent. This study aimed to evaluate whether CT screening in urban areas of China could reduce lung cancer mortality and to investigate the factors that associate with the screening effect.Methods: A decision tree model with three scenarios(low-dose CT screening, chest X-ray screening, and no screening) was developed to compare screening results in a simulated Chinese urban cohort(100,000 smokers aged45-80 years). Data of participant characteristics were obtained from national registries and epidemiological surveys for estimating lung cancer prevalence. The selection of other tree variables such as sensitivities and specificities of low-dose CT and chest X-ray screening were based on literature research. Differences in lung cancer mortality(primary outcome), false diagnoses, and deaths due to false diagnosis were calculated. Sensitivity analyses were performed to identify the factors that associate with the screening results and to ascertain worst and optimal screening effects considering possible ranges of the variables.Results: Among the 100,000 subjects, there were 448,541, and 591 lung cancer deaths in the low-dose CT, chest X-ray, and no screening scenarios, respectively(17.2% reduction in low-dose CT screening over chest X-ray screening and 24.2% over no screening). The costs of the two screening scenarios were 9387 and 2497 false diagnoses and 7and 2 deaths due to false diagnosis among the 100,000 persons, respectively. The factors that most influenced death reduction with low-dose CT screening over no screening were lung cancer prevalence in the screened cohort, lowdose CT sensitivity, and proportion of early-stage cancers among low-dose CT detected lung cancers. Considering all possibilities, reduction in deaths(relative numbers) with low-dose CT screening in the worst and optimal cases were16(5.4%) and 288(40.2%) over no screening, respectively.Conclusions: In terms of mortality outcomes, our findings favor conducting low-dose CT screening in urban China.However, approaches to reducing false diagnoses and optimizing important screening conditions such as enrollment criteria for screening are highly needed.Zixing Wang Wei Han Weiwei Zhang Fang Xue Yuyan Wang Yaoda Hu Lei Wang Chunwu Zhou Yao Huang Shijun Zhao Wei Song Xin Sui Ruihong Shi Jingmei Jiang 2017Chinese Journal of Cancer2017,36,8:9
11Anti-scourability of purple soil on hillslopes with different land uses显示文摘A large-scale flume (40 cm×10 cm×10 cm) was used to determine soil anti-scourability of 4 different land uses of purple soil in hilly areas of Sichuan, China under artificial removal of vegetation to examine the effects of land uses on sediment production by runoff. The results showed that soil anti-scourability declined with the increase of slope gradients in the form of power function, but there was a significant difference in the effects of slope gradients on anti-scourability between different land uses. The ratio of the mean values of soil anti-scourability was 1︰2.2︰2.5︰3.6 for forest land, new waste pasture, old waste pasture, crop land respectively, indicating that forest and grass use can significantly improve soil anti-scourability. Compared with the observations from the runoff plots located at the same sites in this region, an inconsistent result was found between anti-scourability and anti-erodibility in hilly areas of Sichuan. Essential causes of the differences in soil anti-scourability were further discussed based on analyzing the influence of inherent soil characteristics induced by different land uses on soil anti-scourability.ZHANG Jianhui, LIU Gangcai, NI Shijun, ZHU Bo & GE Fanglong Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China Chengdu University of Technology, Chengdu 610059, China 2003Science China(Technological Sciences)2003,46,z1:8
12Gene expression profiling of rat livers with Yin-deficiency-heat syndrome显示文摘OBJECTIVE: To explore the nature of 'Yin internal heat caused byYin-deficiency,' in terms of the theory of Traditional Chinese Medicine, by studying energy metabolism in rats with Yin-deficiency-heat syndrome and analyzing the gene expression profile of their livers. METHODS: A Yin-deficiency-heat syndrome model was induced in rats using three Chinese medicinal herbs. Glycogen and triglycerides in blood plasma, and the enzyme activity of ATP in livers were measured colorimetrically. Triiodothyronine (T3 ), thyroxine (T4 ), and thyroid stimulating hormone levels in blood plasma were also measured with enzyme linked immunosorbent assay. The gene expression profile of livers was detected with gene chip analysis. Differentially expressed genes were screened out and classified according to Gene Ontology. The accuracy of results were examined with reversetranscription-polymerase chain reaction. RESULTS: Compared with the control group, body weight (P<0.05) and hepatic glycogen (P<0.05) were significantly lower in the Yin-deficiency-heat syndrome group. Moreover, toe temperature (P< 0.01) and triglyceride (P<0.05), Na+ -K+ -ATPase (P< 0.01), Mg2+ -ATPase (P<0.01), T3 (P<0.05), and T4 (P< 0.01) levels were significantly higher. There were 99 differentially expressed genes in livers from the Yin-deficiency-heat syndrome group. Genes were mainly related to sterol synthesis (Pc=0.0392), defense response (Pc=0.0448), and sterol metabolism (Pc=0.0533). CONCLUSION: Abnormal expression genes in rats with Yin-deficiency-heat syndrome prompted the synthesis and metabolism of cholesterol, increased energy consumption, and reduced defense response. This gene expression might be the molecular mechanism underlying 'internal heat caused by Yin-deficiency' in the rats with Yin-deficiency-heat syndrome.Bingbing Han Shijun Wang Lin Li YuanWang Haijun Zhao 2013Journal of Traditional Chinese Medicine2013,33,3:8
13Nonlinear dynamics of a flapping rotary wing:Modeling and optimal wing kinematic analysis显示文摘The analysis of the passive rotation feature of a micro Flapping Rotary Wing(FRW)applicable for Micro Air Vehicle(MAV) design is presented in this paper. The dynamics of the wing and its influence on aerodynamic performance of FRW is studied at low Reynolds number(~10~3).The FRW is modeled as a simplified system of three rigid bodies: a rotary base with two flapping wings. The multibody dynamic theory is employed to derive the motion equations for FRW. A quasi-steady aerodynamic model is utilized for the calculation of the aerodynamic forces and moments. The dynamic motion process and the effects of the kinematics of wings on the dynamic rotational equilibrium of FWR and the aerodynamic performances are studied. The results show that the passive rotation motion of the wings is a continuous dynamic process which converges into an equilibrium rotary velocity due to the interaction between aerodynamic thrust, drag force and wing inertia. This causes a unique dynamic time-lag phenomena of lift generation for FRW, unlike the normal flapping wing flight vehicle driven by its own motor to actively rotate its wings. The analysis also shows that in order to acquire a high positive lift generation with high power efficiency and small dynamic time-lag, a relative high mid-up stroke angle within 7–15° and low mid-down stroke angle within -40° to -35° are necessary. The results provide a quantified guidance for design option of FRW together with the optimal kinematics of motion according to flight performance requirement.Qiuqiu WEN Shijun GUO Hao LI Wei DONG 2018Chinese Journal of Aeronautics2018,31,5:8
14Evaluation of drinking water treatment combined filter backwash water recycling technology based on comet and micronucleus assay显示文摘Based on the fact that recycling of combined filter backwash water(CFBW)directly to drinking water treatment plants(WTP)is considered to be a feasible method to enhance pollutant removal efficiency,we were motivated to evaluate the genotoxicity of water samples from two pilot-scale drinking water treatment systems,one with recycling of combined backwash water,the other one with a conventional process.An integrated approach of the comet and micronucleus(MN)assays was used with zebrafish(Danio rerio)to investigate the water genotoxicity in this study.The total organic carbon(TOC),dissolved organic carbon(DOC),and trihalomethane formation potential(THMFP),of the recycling process were lower than that of the conventional process.All the results showed that there was no statistically significant difference(P>0.05)between the conventional and recycling processes,and indicated that the genotoxicity of water samples from the recycling process did not accumulate in 15 day continuous recycling trial.It was worth noting that there was correlation between the concentrations of TOC,DOC,UV_(254),and THMFPs in water and the DNA damage score,with corresponding R^2 values of 0.68,0.63,0.28,and 0.64.Nevertheless,both DNA strand breaks and MN frequency of all water samples after disinfection were higher than that of water samples from the two treatment units,which meant that the disinfection by-products(DBPs)formed by disinfection could increase the DNA damage.Both the comet and MN tests suggest that the recycling process did not increase the genotoxicity risk,compared to the traditional process.Ting Chen Yongpeng Xu Zhiquan Liu Shijun Zhu Wenxin Shi Fuyi Cui 2016Journal of Environmental Sciences2016,28,4:8
15The carbon nanotubes-based materials and their applications for organic pollutant removal: A critical review显示文摘The carbon nanotubes(CNTs) as the emerging materials for organic pollutant removal have gradually become a burgeoning research field.Herein,a mini-review of CNTs-based materials curre ntly studies for organic pollutant elimination is presented.This review summarizes the preparation methods of CNTsbased materials.CNTs-based materials can be used as adsorbents to remove organic pollutants in wastewater.The adsorption mechanisms mainly include surface diffusio n,pore diffusion and adsorption reaction.Most importantly,an in-depth overview of CNTs-based materials currently available in advanced oxidation processes(AOPs) applications for wastewater treatment is proposed.CNTs-based materials can catalyze different oxidants(e.g.,hydrogen peroxide(H2 O2),persulfates(PMS/PDS),ozone(O3) and ferrate/permanganate(Fe(Ⅵ)/Mn(Ⅶ)) to generate more reactive oxygen species(ROS) for organic pollutant elimination.Moreover,the possible reaction mechanisms of removing organic pollutants by CNTs-based materials are summarized systematically and discussed in detail.Finally,application potential and future research directions of CNTs-based materials in the environmental remediation field are proposed.Jiali Peng Yongli He Chenying Zhou Shijun Su Bo Lai 2021Chinese Chemical Letters2021,32,5:7
16Seasonal variation of snow microbial community structure in the East Rongbuk glacier, Mt. Everest显示文摘The bacterial diversity and abundance in the snow of East Rongbuk glacier, Mt. Everest were examined through 16S rRNA gene clone library and flow cytometry approaches. In total, 35 16S rRNA gene sequences were obtained, which belong to α, β, γ-Proteobacteria, Actinobacteria, Firmicutes, CFB, Cyanobacteria, Eukaryotic chloroplast, and TM7 candidate phylum respectively. γ-Proteobacteria was the dominant bacterial group in this region, while the genera Acinetobacter and Leclercia were domi- nant on the genus level. The community structure varied seasonally. The bacterial abundance in sum- mer snow was higher than that in winter. Moreover, the snow bacterial community structures in both seasons were diverse, with not only common species but season-specific species. The common species most likely originated from the Tibet Plateau. Bacteria in summer snow are affiliated with marine environ- ment, whereas bacteria in winter snow are closely related to more diverse environments and show the feature of resistance to cold. Seasonal variations of abundance and bacterial diversity were most proba- bly due to the seasonal characteristics of climate and atmospheric circulation in Mt. Everest.LIU Yongqin YAO Tandong KANG Shichang JIAO Nianzhi ZENG Yonghui SHI Yang LUO Tingwei JING Zhefang HUANG Shijun 2006Chinese Science Bulletin2006,51,12:7
17Rational cutting height for large cutting height fully mechanized top-coal caving显示文摘Large cutting height fully mechanized top-coal caving is a new mining method that improves recovery ratio and single-pass production. It also allows safe and efficient mining. A rational cutting height is one key parameter of this technique. Numerical simulation and a granular-media model experiment were used to analyze the effect of cutting height on the rock pressure of a fully mechanized top-coal caving work face. The recovery ratio was also studied. As the cutting height increases the top-coal thickness is reduced. Changing the ratio of cutting to drawing height intensifies the face pressure and the top-coal shattering. A maximum cutting height exists under a given set of conditions due to issues with surrounding rock-mass control. An increase in cutting height makes the top-coal cave better and the recovery ratio when drawing top-coal is then improved. A method of adjusting the face rock pressure is presented. Changing the cutting to drawing height ratio is the technique used to control face rock pressure. The recovery ratio when cutting coal exceeds that when caving top-coal so the face recovery ratio may be improved by over sizing the cutting height and increasing the top-coal drawing ratio. An optimum ratio of cutting to drawing height exists that maximizes the face recovery ratio. A rational cutting height is determined by comprehensively considering the surrounding rock-mass control and the recovery ratio. At the same time increasing the cutting height can improve single pass mining during fully mechanized top-coal caving.Huang Bingxiang Li Hongtao Liu Changyou Xing Shijun Xue Weichao 2011Mining Science and Technology2011,21,3:7
18Liquid crystal integrated metalens with tunable chromatic aberration显示文摘Overcoming chromatic aberrations is a vital concern in imaging systems in order to facilitate fullcolor and hyperspectral imaging.By contrast,large dispersion holds opportunities for spectroscopy and tomography.Combining both functions into a single component will significantly enhance its versatility.A strategy is proposed to delicately integrate two lenses with a static resonant phase and a switchable geometric phase separately.The former is a metasurface lens with a linear phase dispersion.The latter is composed of liquid crystals(LCs)with space-variant orientations with a phase profile that is frequency independent.By this means,a broadband achromatic focusing from 0.9 to 1.4 THz is revealed.When a saturated bias is applied on LCs,the geometric phase modulation vanishes,leaving only the resonant phase of the metalens.Correspondingly,the device changes from achromatic to dispersive.Furthermore,a metadeflector with tunable dispersion is demonstrated to verify the universality of the proposed method.Our work may pave a way toward active metaoptics,promoting various imaging applications.Zhixiong Shen Shenghang Zhou Xinan Li Shijun Ge Peng Chen Wei Hu Yanqing Lu 2020Advanced Photonics2020,2,3:7
19Sensors deployment optimization in multi-dimensional space based on improved particle swarm optimization algorithm显示文摘Sensors deployment optimization has become one of the most attractive fields in recent years. However, most of the previous work focused on the deployment problem in 2 D space.Compared to the traditional form, sensors deployment in multidimensional space has greater research significance and practical potential to satisfy the detecting needs in complex environment.Aiming at solving this issue, a multi-dimensional space sensor network model is established, and the radar system is selected as an example. Considering the possible working mode of the radar system(e.g., searching and tracking), two distinctive deployment models are proposed based on maximum coverage area and maximum target detection probability in the attack direction respectively. The latter one is usually ignored in the previous literature.For uncovering the optimal deployment of the sensor network, the particle swarm optimization(PSO) algorithm is improved using the proposed weights determination scheme, in which the linear decreasing, the pooling strategy and the cloud theory are combined for weights updating. Experimental results illustrate the effectiveness of the proposed method.TANG Mingnan CHEN Shijun ZHENG Xuehe WANG Tianshu CAO Hui 2018Journal of Systems Engineering and Electronics2018,29,5:6
20Effects of electroacupuncture on microcirculatory blood flow and glucose transporter function in the hippocampus显示文摘Nerve cell metabolism in post brain ischemia depends on increased microcirculation perfusion and transport function of microvascular endothelial cells.In the present study,a rat model of middle cerebral artery occlusion was established to investigate the influence of electroacupuncture(EA) on hippocampal CA1 cerebral blood flow and glucose transporter 1(GLUT1) expression in the microvascular endothelial cells.Following EA at Neiguan(PC 6),the cerebral blood flow in the ischemic hippocampal CA1 region was significantly elevated,the number and microvascular integrated absorbance of the GLUT1-positive cells were significantly increased,nerve cell damage was ameliorated,and GLUT1 protein expression in the ischemic hippocampus was significantly increased.Results demonstrate that EA increased the cerebral blood flow of the hippocampal CA1 region and improved the glucose transport function,thereby attenuating neuronal injuries.Lu, Yan Han, Bingbing Wang, Shijun 2011Neural Regeneration Research2011,6,3:6
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