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92篇 您的检索式:作者名="LIXIN ZHENG"
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1Developing the Science Product Algorithm Testbed for Chinese Next-Generation Geostationary Meteorological Satellites:Fengyun-4 Series显示文摘Fengyun-4A(FY-4A), the first of the Chinese next-generation geostationary meteorological satellites, launched in2016, offers several advances over the FY-2: more spectral bands, faster imaging, and infrared hyperspectral measurements. To support the major objective of developing the prototypes of FY-4 science algorithms, two science product algorithm testbeds for imagers and sounders have been developed by the scientists in the FY-4 Algorithm Working Group(AWG). Both testbeds, written in FORTRAN and C programming languages for Linux or UNIX systems, have been tested successfully by using Intel/g compilers. Some important FY-4 science products, including cloud mask, cloud properties, and temperature profiles, have been retrieved successfully through using a proxy imager, Himawari-8/Advanced Himawari Imager(AHI), and sounder data, obtained from the Atmospheric Infra Red Sounder, thus demonstrating their robustness. In addition, in early 2016, the FY-4 AWG was developed based on the imager testbed—a near real-time processing system for Himawari-8/AHI data for use by Chinese weather forecasters.Consequently, robust and flexible science product algorithm testbeds have provided essential and productive tools for popularizing FY-4 data and developing substantial improvements in FY-4 products.Min MIN Chunqiang WU Chuan LI Hui LIU Na XU Xiao WU Lin CHEN Fu WANG Fenglin SUN Danyu QIN Xi WANG Bo LI Zhaojun ZHENG Guangzhen CAO Lixin DONG 2017Journal of Meteorological Research2017,31,4:35
2Study on the antiulcer effects of Veronicastrum axillare on gastric ulcer in rats induced by ethanol based on tumor necrosis factor-α(TNF-α)and endothelin-1(ET-1)显示文摘Objective:To assess whether Veronicastrum axillare(V.axillare)can ameliorate ethanol-induced gastric mucosal lesions in rats,reduce the production of pro-inflammatory cytokines,suppress apoptosis and improve local microcirculation disturbances.Methods:Totally 48 male Sprague-Dawley rats were randomly divided into six groups,eight rats in each group.Rats in the normal group and the model group were administered with 0.9%normal saline respectively.Rats in the positive group and ranitidine group were administered with 0.18%ranitidine suspension by intragastric administration respectively.Those in the high dose V.axillare group,the medium dose V.axillare group and the low dose V.axillare group were administrated with V.axillare at the daily dose of 2.8 g/kg,1.4 g/kg and 0.7 g/kg by intragastric administration.Gastric mucosal lesions were produced by intragastric administration of absolute ethanol.Water extract of V.axillare was successively injected for 14 d and last day was injected 1 h before ethanol administration.Gastric mucosal ulcer index and ulcer inhibitory rate were counted by improved Guth methods.The tissue sections were made for pathological histology analysis.Also,we measured the concentrations of tumor necrosis factor-α(TNF-α)and endothelin-1(ET-1)in gastric mucosal,as an index of the pro-inflammatory cytokines,apoptosis and local microcirculation.Besides,the mRNA contents of TNF-αand ET-1 were measured to verify effects on gene expression by real-time fluorescent quantitative PCR.Results:Water extract of V.axillare significantly ameliorated the gastric mucosal lesions induced by ethanol administration(P<0.01).Pro-inflammatory cytokines,TNF-a and ET-1 were increased after ethanol administration and significantly reduced by water extract of V.axillare.The expressions of TNF-αand ET-1 mRNA were also be inhibited by water extract of V.axillare.Conclusion:Current evidences show water extract of V.axillare is effective for defending against ethanol-induced gastric mucosal lesions,significantly inhibiting the production of proinflammatory cytokines and the expressions of TNF-αand ET-1 mRNA,which may be useful for inhibiting apoptosis and improving local microcirculation.Yong Du Weichun Zhao Leilei Lu Jiayan Zheng Xishi Hu Zhehan Yu Lixin Zhu 2013Asian Pacific Journal of Tropical Biomedicine2013,3,12:13
3Composite structure and properties of the pitcher surface of the carnivorous plant Nepenthes and its influence on the insect attachment system显示文摘食肉的植物能使人忘忧的东西的投球手发展了服务吸引的目的专业化器官,捕获,保留并且消化小动物,主要昆虫。他们由几个很好可区分的地区组成,包括一个像叶子的盖,像领子的蒴齿,一个滑溜溜的地区和一个消化地区,在形态学,微观结构,化学作文和物理性质不同。区别地区显示不同功能,并且几个地区的联合效果导致套住效率的伟人。这评论的主要目的是介绍结构和投球手表面,以及在投球手表面和昆虫附件系统之间的相互作用的 physiochemical 性质。与我们的现在的学习结合,投球手表面的潜在的应用程序在 bionics 正在被利用生产昆虫滑溜溜的套住盘子被讨论,并且投球手表面的创新研究方向和它农业害虫控制上的应用程序被加亮。Lixin Wang Qiang Zhou Yongjun Zheng Shuyan Xu 2009Progress in Natural Science:Materials International2009,19,12:8
4Changes in the gut microbiota mediate the differential regulatory effects of two glucose oxidases produced by Aspergillus niger and Penicillium amagasakiense on the meat quality and growth performance of broilers显示文摘Background: Glucose oxidase(GOD), an aerobic dehydrogenase, has been used as an antibiotic substitute in feed.A study was conducted to evaluate the differential effects of 2 different GODs fermented by Aspergillus niger or Penicillium amagasakiense on caecal microbiota and to further illuminate the potential roles of changes in the gut microbiota in regulating the growth performance and meat quality of broiler chickens.Results: A total of 420 one-day-old healthy Arbor Acres broilers were randomly assigned to 4 treatments: the control group,the antibiotic growth promoter(AGP) supplementation group, and the GOD-A and GOD-P(GODs produced by A. niger and P. amagasakiense, respectively) groups. As a result, supplementation with GOD produced by P. amagasakiense could significantly improve the average daily weight gain and average daily feed intake of broilers before 21 days of age by significantly increasing the enzymatic activities of jejunal amylase and those of ileal amylase, chymotrypsin, and lipase in21-day-old broilers and could increase the enzymatic activities of duodenal amylase, jejunal amylase and lipase, and ileal chymotrypsin and lipase in 42-day-old broilers. Meanwhile, compared with AGP treatment, supplementation with GOD produced by P. amagasakiense significantly decreased the L value of 21-day-old broilers and the Δp H and L* value of 42-day-old broilers, while supplementation with GOD produced by A. niger significantly increased the p H24 hvalue of 21-day-old and 42-day-old broilers by reducing plasma malondialdehyde content. By using 16 S r RNA sequencing, we found that the beneficial bacteria and microbiota in broilers were not disturbed but were improved by GOD supplementation compared with ADP treatment, including the genera Eubacterium and Christensenel a and the species uncultured_Eubacterium_sp,Clostridium_asparagiforme, and uncultured_Christensenel a_sp, which were positively related to the improved intestinal digestive enzymatic activities, growth performance, and meat quality of broilers.Conclusion: The altered gut microbiota induced by supplementation with glucose oxidase produced by P. amagasakiense mediate better regulatory effects on the meat quality and growth performance of broilers than that induced by supplementation with glucose oxidase produced by A. niger.Shengru Wu Xiaodong Chen Taohuan Li Hao Ren Lixin Zheng Xiaojun Yang 2020Journal of Animal Science and Biotechnology2020,11,4:7
5Effectiveness of Catch-Up Vaccinations after COVID-19 Containment--China,2020显示文摘Introduction:In the early stages of the coronavirus disease 2019(COVID-19)epidemic in China,the highest level of public health emergency response(Level 1 Response)was launched in all province-level administrative divisions(PLADs)across the country.Provision of vaccination services was selectively suspended due to the physical distancing and gathering restrictions required of Level 1 Response.The purpose of this paper is to evaluate the impact of COVID-19 on vaccination services and the effectiveness of selective vaccination service suspension and catch-up vaccinations in China.Methods:Vaccine doses administered,routine vaccination coverage levels,catch-up vaccine doses administered,and coverage levels after the catch-up campaign were determined from individual vaccination records in sampled clinics,standard routine immunization administrative coverage reports,and catch-up vaccination activity reports submitted by PLADs between October 2019 and October 2020.Results:National Immunization Program(NIP)and non-NIP vaccine doses administered in sampled clinics decreased by 80% and 90%,respectively,compared with doses administered before the COVID-19 pandemic.Coverage with the birth dose of hepatitis B vaccine(HepB1)and the Bacillus Calmette-Guérin vaccine(BCG)—two vaccinations recommended to continue throughout the epidemic due to their timecritical nature—were maintained at over 85%,while coverage of other NIP vaccines decreased to below 60%by February 2020.Catch-up vaccination coverage of the 29 PLADs,excluding Xinjiang and Xizang(Tibet),began in April 2020 and exceeded 90%;Hubei catch-up coverage was 95% by October 2020.Conclusions and Implications for Public Health Practice:The COVID-19 pandemic had a great impact on China’s vaccination services.During the epidemic and time of local transmission of the coronavirus,HepB1,BCG,rabies vaccine for postexposure prophylaxis,and tetanus antitoxin(TAT)for wound prophylaxis were maintained at high levels.Of the 69 million vaccine doses postponed during the time of local transmission of the coronavirus,94% were administered in the catch-up campaign.China’s pandemic immunization practices may provide evidence for other countries’immunization programs.Jing Wu Wenzhou Yu Lei Cao Lingsheng Cao Lance Rodewald Jiakai Ye Yifan Song Li Li Xiaoxue Liu Ning Wen Fuzhen Wang Lixin Hao Yixing Li Hui Zheng Keli Li Chao Ma Dan Wu Yanmin Liu Guomin Zhang Zhijie An Huaqing Wang Zundong Yin 2020China CDC weekly2020,2,50:6
6The ultraviolet and blue luminescence properties of ZnO:Zn thin film显示文摘The ultraviolet (UV) and blue luminescence of Zn-rich zinc oxide thin film deposited by electron-beam evaporation have been investigated at room temperature (RT). We observed that the UV and blue electroluminescence (EL) emission band centered around 480 nm which is blue shifted in comparison with that of the ZnO thin film prepared by low pressure metal organic chemical vapor deposition (LP MOCVD). The UV emission is much stronger than blue emission in the photoluminescence (PL) spectra. The field-induced ionization of excited luminescent centers of ZnO:Zn thin film at high electric field and the difference between PL and EL are discussed. The experiments show that the ZnO:Zn thin film provides a hopeful new mechanism to obtain UV and blue emission.Lixin Yi Zheng Xu Yanbing Hou Xiqing Zhang Yongsheng Wang Xurong Xu 2001Chinese Science Bulletin2001,46,14:6
7High He-ion irradiation resistance of CrMnFeCoNi high-entropy alloy revealed by comparison study with Ni and 304SS显示文摘High entropy alloys(HEAs) have presented potential applications in nuclear power plants owing to their novel atomic structure based high irradiation resistance. However, understanding of He-ion irradiation of HEAs is still lacking. In this work, we reveal He-ion irradiation resistance of HEA CrMnFeCoNi by comparison study with a pure Ni and a 304 stainless steel(304SS). It is found that the damage structure in the three materials can be characterized with He bubbles and stacking faults/stacking fault tetrahedrons((SFs/SFTs), which show a similar depth distribution after He-ion irradiation at both RT and 450℃.Although the He bubbles have a similar size about 2nm after irradiation at RT, the He bubble sizes of the HEA, 304SS, and Ni increase to 4.0±0.9,5.3±1.0 and 6.7 ±1.0 nm after irradiation at 450℃, respectively. Moreover, the density of SFs/SFTs displays in an order of Ni < 304 SS < HEA at both RT and 450℃.The He-ion irradiation at RT causes significant hardness enhancement for the three materials, however,compared to RT, after irradiation at 450℃, the Ni presents softening, while the 304SS, especially the HEA,shows further hardening. Thus, the HEA CrMnFeCoNi possesses the smallest He bubble size, the densest SFs/SFTs, and the highest hardening, indicating the best structural stability, as well as the best He-ion irradiation resistance, which can be attributed to its low mobility of He atoms and point defects.Lixin Yang Hualong Ge Jian Zhang Ting Xiong Qianqian Jin Yangtao Zhou Xiaohong Shao Bo Zhang Zhengwang Zhu Shijian Zheng Xiuliang Ma 2019Journal of Materials Science & Technology2019,35,3:5
8Tribological properties of TiAlN-coated cermets显示文摘Ti(C,N)-based cermets were coated with TiAlN using multi-arc ion plating technology. Sliding wear tests were performed on the coated cermets. The microstructure and morphologies of the coated cermets before and after friction and wear tests were characterized. The results show that the TiAlN coating surface was smooth and its root mean square roughness was 16.6 nm. The hardness (HK) of TiAlN coating lay-ers reached approximately 3200 and the critical load (Lc) under which the coating failure occurred was 59 N. The sliding wear test results show that the friction coefficients of the TiAlN-coated cermets were lower than that of the cermets without any coating. Under the same load, the adhesion phenomenon of the counterpart materials on the specimens was improved and the mean friction coefficient increased with in-creasing sliding velocity. When the sliding velocity was 0.26 m·s-1, the mass of the coated cermets reduced. At the same sliding velocity, the average friction coefficient of the TiAlN-coated cermets was lower under a higher load. The wear mechanisms of the TiAlN-coated cermets were mainly adhesive and abrasive wear.ZHENG Liyun ZHAO Lixin XIONG Weihao 2009Rare Metals2009,28,1:4
9Joint horizontal and vertical deep learning feature for vehicle re-identification显示文摘Dear editor,Vehicle re-identification is a procedure in which a query image of a vehicle can be matched to vehicle images captured by different cameras in a data gallery.This procedure is extremely important for the improvement of public safety;however,accurately re-identifying vehicles is a very challenging computer vision task because vehicle images are captured from different camera view-points and they usually contain large variations in appearances.Therefore,the development of an effective vehicle re-identification method is both challenging and socially meaningful.Jianqing ZHU Huanqiang ZENG Xin JIN Yongzhao DU Lixin ZHENG Canhui CAI 2019Science China(Information Sciences)2019,62,9:4
10High rumen degradable starch decreased goat milk fat via trans-10,cis-12 conjugated linoleic acid-mediated downregulation of lipogenesis genes,particularly,INSIG1显示文摘Background:Starch is an important substance that supplies energy to ruminants.To provide sufficient energy for high-yielding dairy ruminants,they are typically fed starch-enriched diets.However,starch-enriched diets have been proven to increase the risk of milk fat depression(MFD)in dairy cows.The starch present in ruminant diets could be divided into rumen-degradable starch(RDS)and rumen escaped starch(RES)according to their different degradation sites(rumen or intestine).Goats and cows have different sensitivities to MFD.Data regarding the potential roles of RDS in milk fat synthesis in the mammary tissue of dairy goats and in regulating the occurrence of MFD are limited.Results:Eighteen Guanzhong dairy goats(day in milk=185±12 d)with similar parity,weight,and milk yield were selected and randomly assigned to one of three groups(n=6),which were fed an LRDS diet(Low RDS=20.52%),MRDS diet(Medium RDS=22.15%),or HRDS diet(High RDS=24.88%)for 5 weeks.Compared with that of the LRDS group,the milk fat contents in the MRDS and HRDS groups significantly decreased.The yields of short-,mediumand long-chain fatty acids decreased in the HRDS group.Furthermore,increased RDS significantly decreased ruminal B.fibrisolvens and Pseudobutyrivibrio abundances and increased the trans-10,cis-12 conjugated linoleic acid(CLA)and trans-10 C18:1 contents in the rumen fluid.A multiomics study revealed that the HRDS diet affected mammary lipid metabolism down-regulation of ACSS2,MVD,AGPS,SCD5,FADS2,CERCAM,SC5D,HSD17B7,HSD17B12,ATM,TP53RK,GDF1 and LOC102177400.Remarkably,the significant decrease of INSIG1,whose expression was depressed by trans-10,cis-12 CLA,could reduce the activity of SREBP and,consequently,downregulate the downstream gene expression of SREBF1.Conclusions:HRDS-induced goat MFD resulted from the downregulation of genes involved in lipogenesis,particularly,INSIG1.Specifically,even though the total starch content and the concentrate-to-fiber ratio were the same as those of the high-RDS diet,the low and medium RDS diets did not cause MFD in lactating goats.Lixin Zheng Shengru Wu Jing Shen Xiaoying Han Chunjia Jin Xiaodong Chen Shengguo Zhao Yangchun Cao Junhu Yao 2020Journal of Animal Science and Biotechnology2020,11,3:4
11The Tibetan Plateau Surface–Atmosphere Coupling System and Its Weather and Climate Effects: The Third Tibetan Plateau Atmospheric Science Experiment显示文摘The Tibetan Plateau(TP) is a key area affecting forecasts of weather and climate in China and occurrences of extreme weather and climate events over the world. The China Meteorological Administration, the National Natural Science Foundation of China, and the Chinese Academy of Sciences jointly initiated the Third Tibetan Plateau Atmospheric Science Experiment(TIPEX-Ⅲ) in 2013, with an 8–10-yr implementation plan. Since its preliminary field measurements conducted in 2013, routine automatic sounding systems have been deployed at Shiquanhe, Gaize, and Shenzha stations in western TP, where no routine sounding observations were available previously. The observational networks for soil temperature and soil moisture in the central and western TP have also been established. Meanwhile, the plateau-scale and regional-scale boundary layer observations, cloud–precipitation microphysical observations with multiple radars and aircraft campaigns, and tropospheric–stratospheric air composition observations at multiple sites, were performed. The results so far show that the turbulent heat exchange coefficient and sensible heat flux are remarkably lower than the earlier estimations at grassland, meadow, and bare soil surfaces of the central and western TP. Climatologically, cumulus clouds over the main body of the TP might develop locally instead of originating from the cumulus clouds that propagate northward from South Asia. The TIPEX-Ⅲ observations up to now also reveal diurnal variations, macro-and microphysical characteristics, and water-phase transition mechanisms, of cumulus clouds at Naqu station. Moreover, TIPEX-Ⅲ related studies have proposed a maintenance mechanism responsible for the Asian 'atmospheric water tower' and demonstrated the effects of the TP heating anomalies on African, Asian, and North American climates. Additionally, numerical modeling studies show that the Γ distribution of raindrop size is more suitable for depicting the TP raindrop characteristics compared to the M–P distribution, the overestimation of sensible heat flux can be reduced via modifying the heat transfer parameterization over the TP, and considering climatic signals in some key areas of the TP can improve the skill for rainfall forecast in the central and eastern parts of China. Furthermore, the TIPEX-Ⅲ has been promoting the technology in processing surface observations, soundings, and radar observations, improving the quality of satellite retrieved soil moisture and atmospheric water vapor content products as well as high-resolution gauge–radar–satellite merged rainfall products, and facilitating the meteorological monitoring, forecasting, and data sharing operations.Ping ZHAO Yueqing LI Xueliang GUO Xiangde XU Yimin LIU Shihao TANG Wenming XIAO Chunxiang SHI Yaoming MA Xing YU Huizhi LIU La JIA Yun CHEN Yanju LIU Jian LI Dabiao LUO Yunchang CAO Xiangdong ZHENG Junming CHEN An XIAO Fang YUAN Donghui CHEN Yang PANG Zhiqun HU Shengjun ZHANG Lixin DONG Juyang HU Shuai HAN Xiuji ZHOU 2019Journal of Meteorological Research2019,33,3:4
12Clinical and pathological features of miR-10b and RHOC gene expression in hepatocellular carcinoma显示文摘Aberrant expression of microRNAs(miRNAs)was reported frequently in different human cancers.The major role of miRNA is targeting 30-UTR of coding gene and causing translational repression or mRNA degradation.miR-10b overexpression was reported to promote breast cancer metastasis by up-regulating RHOC expression.But its expression in hepatocellular carcinoma(HCC)remains unclear.Our study indicated that the expression of miR-10b was different in HCC and adjacent tissue samples,and reduced expression of miR-10b in HCC was related tovein invasion.High-level expression of RHOC was also related to vein invasion in HCC.But no correlation was found between miR-10b and RHOC expression.These results suggest that miR-10b and RHOC are independent predictors of HCC invasion and metastasis.Jingli Du Yulan Wang Hanjiang Fu Xiaofei Zheng Minggui Lin Mingzhou Guo Lixin Wei 2014Chinese Science Bulletin2014,59,19:4
13Development of the generic drug industry in the US after the Hatch-Waxman Act of 1984显示文摘The key events in the development of the US generic drug industry after the Hatch-Waxman Act of 1984 are systematically reviewed,including the process of approval for generic drugs,bioequivalence issues including“switchability”,bioequivalence for complicated dosage forms,patent extension,generic drug safety,generic substitution and low-cost generics.The backlog in generic review,generic drug user fees,and“quality by design”for generic drugs is also discussed.The evolution of the US generic drug industry after the Hatch-Waxman Act in 1984 has afforded several lessons of great benefit to other countries wishing to establish or re-establish a domestic generic drug industry.Garth Boehm Lixin Yao Liang Han Qiang Zheng 2013Acta Pharmaceutica Sinica B2013,3,5:4
14Metagenome analysis reveals potential microbial functions in topsoil of wheat-maize rotation system with five-year application of fertilizers显示文摘Fertilization mode affects soil quality and ecological health.The effects of four fertilization regimens on lignocellulose content,readily degradable carbohydrate decomposition,and potential microbial functions in the topsoil of a wheat-maize rotation system between 2012 and 2017 were investigated.The fertilization regimens of control(control NFNB),high chemical fertilizer(HCF),high biochar plus low chemical fertilizer(HBLCF),and biochar-based fertilizer(BBF)were compared on soil fundamental properties,microbial structure,and potential function in soil carbohydrate degradation based on metagenome analysis.The diversity of carbohydrate-active enzyme genes in the topsoil microbial consortia in the four trials was primarily distributed within the ten ecologically most dominant phyla.Application of BBF was associated with the lowest decline in total nitrogen and P2O5(2012-2017:6.5%and 28.1%,respectively)and the most effective carbohydrate decomposition(2015-2017:67.0%for cellulose and 59.9%for readily degradable carbohydrate).Carbohydrate transport and metabolism accounted for 6.0%of reads assigned functional classification under the BBF regimen.These findings reveal the ecologically functional diversity of topsoil microorganisms and suggest BBF application as a promising strategy for sustainable agriculture and beneficial to soil health.Yujun Shen Lixin Zhao Haibo Meng Hongsheng Cheng Jingtao Ding Jiarui Wang Shanshan Dong Xi Zhang Liqiu Song Shengwei Zheng 2019International Journal of Agricultural and Biological Engineering2019,12,6:3
15Recent Research Developments of Perovskite Solar Cells显示文摘For the first time in 2009,the inorganic-organic hybrid perovskite materials were applied in liquid dye-sensitized solar cells.In 2013,the power conversion efficiency successfully reached 15%,followed by great amount of research papers bursting out.Till August 2014,the highest efficiency is certified to 17.9%,and the reported efficiency is even up to 19.3%.They quickly go beyond dye-sensitized solar cells and organic solar cells.It is expected the perovskite has its efficiency same to the single-crystal silicon cells.The“game changer”of solar cells is coming.The perovskite solar cells are cheap and easily to be made,which will benefit both science and industry.This review summarized recent development of both perovskite materials and solar cell devices,not only including new material developments of perovskite compositions,structures,and fabrication methods,but also focusing on device structures,charge transfer mechanism and stability properties of perovskite solar cells.Their perspective is also estimated.Yingzhuang Ma Shufeng Wang Lingling Zheng Zelin Lu Danfei Zhang Zuqiang Bian Chunhui Huang Lixin Xiao 2014Chinese Journal of Chemistry2014,32,10:3
16Community phylogenetic structure of grasslands and its relationship with environmental factors on the Mongolian Plateau显示文摘The community assembly rules and species coexistence have always been interested by ecologists. The community phylogenetic structure is the consequence of the interaction process between the organisms and the abiotic environment and has been used to explain the relative impact of abiotic and biotic factors on species co-existence. In recent years, grassland degradation and biodiversity loss have become increasingly severe on the Mongolian Plateau, while the drivers for these changes are not clearly explored, especially whether climate change is a main factor is debated in academia. In this study, we examined the phylogenetic structure of grassland communities along five transects of climate aridity on the Mongolian Plateau, and analyzed their relations with environmental factors, with the aims to understand the formation mechanism of the grassland communities and the role of climatic factors. We surveyed grassland communities at 81 sites along the five transects, and calculated their net relatedness index(NRI) at two different quadrat scales(small scale of 1 m2 and large scale of 5 m2) to characterize the community phylogenetic structure and analyze its relationship with the key 11 environmental factors. We also calculated the generalized UniFrac distance(GUniFrac) among the grassland communities to quantify the influence of spatial distance and environmental distance on the phylogenetic β diversity. The results indicated that plant community survey using the large scale quadrat contained sufficient species to represent community compositions. The community phylogenetic structure of grasslands was significantly overdispersed at both the small and large scales, and the degree of overdispersion was greater at the large scale than at the small scale, suggesting that competitive exclusion instead of habitat filtering played a major role in determination of community composition. Altitude was the main factor affecting the community phylogenetic structure, whereas climatic factors, such as precipitation and temperature, had limited influence. The principal component analysis of the 11 environmental factors revealed that 94.04% of their variation was accounted by the first four principal components. Moreover only 14.29% and 23.26% of the variation in community phylogenetic structure were explained by the first four principal components at the small and large scales, respectively. Phylogenetic β diversity was slightly significantly correlated with both spatial distance and environmental distance, however, environmental distance had a less explanatory power than spatial distance, indicating a limited environmental effect on the community phylogenetic structure of grasslands on the Mongolian Plateau. In view of the limited effect of climatic factors on the community phylogenetic structure of grasslands, climate change may have a smaller impact on grassland degradation than previously thought.DONG Lei LIANG Cunzhu LI Frank Yonghong ZHAO Liqing MA Wenhong WANG Lixin WEN Lu ZHENG Ying LI Zijing ZHAO Chenguang Indree TUVSHINTOGTOKH 2019Journal of Arid Land2019,11,4:2
17Factors controlling geochemical and mineralogical compositions of coals preserved within marine carbonate successions: A case study from the Heshan Coalfield, southern China显示文摘Shifeng Dai Weiguo Zhang Vladimir V. Seredin Colin R. Ward James C. Hower Weijiao Song Xibo Wang Xiao Li Lixin Zhao Huan Kang Licai Zheng Peipei Wang Dao Zhou 2013International Journal of Coal Geology2013,,:2
18Textbook Outcome as a measure of surgical quality assessment and prognosis in gastric neuroendocrine carcinoma:A large multicenter sample analysis显示文摘Objective:Quality assurance is crucial for oncological surgical treatment assessment.For rare diseases,singlequality indicators are not enough.We aim to develop a comprehensive and reproducible measurement,called the'Textbook Outcome'(TO),to assess the quality of surgical treatment and prognosis of gastric neuroendocrine carcinoma(G-NEC)patients.Methods:Data from patients with primary diagnosed G-NEC included in 24 high-volume Chinese hospitals from October 2005 to September 2018 were analyzed.TO included receiving a curative resection,≥15 lymph nodes examined,no severe postoperative complications,hospital stay≤21 d,and no hospital readmission≤30 d after discharge.Hospital variation in TO was analyzed using a case mix-adjusted funnel plot.Prognostic factors of survival and risk factors for non-Textbook Outcome(non-TO)were analyzed using Cox and logistic models,respectively.Results:TO was achieved in 56.6%of 860 G-NEC patients.TO patients had better overall survival(OS),disease-free survival(DFS),and recurrence-free survival(RFS)than non-TO patients(P<0.05).Moreover,TO patients accounted for 60.3%of patients without recurrence.Multivariate Cox analysis revealed non-TO as an independent risk factor for OS,DFS,and RFS of G-NEC patients(P<0.05).Increasing TO rates were associated with improved OS for G-NEC patients,but not hospital volume.Multivariate logistic regression revealed that nonlower tumors,open surgery,and>200 mL blood loss were independent risk factors for non-TO patients(P<0.05).Conclusions:TO is strongly associated with multicenter surgical quality and prognosis for G-NEC patients.Factors predicting non-TO are identified,which may help guide strategies to optimize G-NEC outcomes.Qiyue Chen Zhongliang Ning Zhiyu Liu Yanbing Zhou Qingliang He Yantao Tian Hankun Hao Wei Lin Lixin Jiang Gang Zhao Ping Li Chaohui Zheng Changming Huang on behalf of the Study Group for Gastric Neuroendocrine Tumors 2021Chinese Journal of Cancer Research2021,33,4:2
19Branched Fluorine/Adamantane Interfacial Compatibilizer for PBO Fibers/Cyanate Ester Wave-Transparent Laminated Composites显示文摘Comprehensive Summary Branched fluorine/adamantane PBO precursor(preFABPBO),synthesized via random co-condensation between 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoro propane,1,3-adamantanedicarbonyl dichloride,and trimesoyl chloride,is performed as interfacial compatibilizer,bisphenol A dicyanate ester(BADCy)resin as polymer matrix,and poly(p-phenylene-2,6-benzobisoxazole)(PBO)fibers as reinforcements to prepare PBO fibers/FABPBO-BADCy wave-transparent laminated composites by high temperature molding.The mechanical properties,wave-transparent performances,and heat resistances of PBO fibers/BADCy composites are simultaneously improved by the addition of preFABPBO.The interlaminar shear strength(ILSS)and flexural strength of PBO fibers/FABPBO-BADCy composites are 48.9 and 665.3 MPa,respectively,increased by 33.2%and 13.3%compared to those of PBO fibers/BADCy composites(36.7 and 587.4 MPa).The dielectric constant and dielectric loss values at 106 Hz are 2.53 and 0.003,respectively,lower than those of PBO fibers/BADCy composites(3.06 and 0.006),and the corresponding wave transmission efficiency is 94.8%,which also presents excellent stability over the wide temperature(25-200℃)and frequency range(103-107 Hz and 8.2-12.4 GHz).Meanwhile,the heat resistance index and glass transition temperature are 229.9℃and 247.5℃,also better than those of PBO fibers/BADCy composites(229.6℃and 247.1℃).Zheng Liu Xiaoli Fan Muyi Han Hao Li Junliang Zhang Lixin Chen Qiju Zhu Junwei Gu 2023Chinese Journal of Chemistry2023,41,8:2
20PBO fibers/fluorine-containing liquid crystal compound modified cyanate ester wave-transparent laminated composites with excellent mechanical and flame retardance properties显示文摘Bisphenol A dicyanate ester resins modified by fluorine-containing liquid crystal compound(LCFE)are applied as polymer matrix(LCFE-BADCy),poly(p-phenylene-2,6-benzobisoxazole)(PBO)fibers as rein-forcements,and fluorine/adamantane PBO precursor(pre FABPBO)as interfacial compatibilizer to prepare the corresponding PBO fibers/FABPBO/LCFE-BADCy wave-transparent laminated composites.LCFE could improve the order degree of BADCy cured network,in favor of enhancing the wave-transparent perfor-mance,mechanical properties,and intrinsic thermal conductivity.The dielectric constant and dielectric loss of PBO fibers/FABPBO/LCFE-BADCy composites are highly temperature(25–200℃)and frequency(10^(4)–10^(7) Hz and 8.2–12.4 GHz)stable with the value of 2.49 and 0.003 under 10^(6) Hz at 25℃,and the corresponding wave transmission efficiency is 95.0%,higher than that of 92.5%for PBO fibers/BADCy com-posites.The interlamellar shear strength and flexural strength are respectively 50.7 MPa and 682.5 MPa,38.1%and 16.2%higher than those of PBO fibers/BADCy composites.Besides,the volume resistivity,breakdown voltage,heat resistance index,glass transition temperature,flame retardant grade,and ul-timate oxygen index of PBO fibers/FABPBO/LCFE-BADCy composites are respectively 5.3×10^(15)Ωcm,29.75 kV/mm,217.2℃,245.7℃,V-1 grade,and 33.6%,expected to be performed as a new generation of“lightweight/loading/wave-transparent”electromagnetic window materials in advanced military weapons and civil communication base station.Zheng Liu Xiaoli Fan Junliang Zhang Lixin Chen Yusheng Tang Jie Kong Junwei Gu 2023Journal of Materials Science & Technology2023,,21:2
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