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Foliar stoichiometry under different mycorrhizal types in relation to temperature and precipitation in grassland

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Journal of Plant Ecology 2013年第4期6卷 270-276页

作者： Zhaoyong Shi Xiaogai hou Yinglong Chen Fayuan Wangan Yanfang Miao Agricultural College Henan University of Science and TechnologyLuoyangHenan 471003China Laboratory for Earth Surface Processes Ministry of EducationPeking UniversityBeijing 100871China College of Life Sciences Hebei UniversityBaoding 071002China School of Earth and Environment Faculty of Natural and Agricultural SciencesThe University of Western AustraliaPerthAustralia

Aims mycorrhizas play key roles in important ecosystem processes and ***(C),nitrogen(N)and phosphorus(P)concentrations and their ratios are very important foliar traits and their cycling constrains most ecosystem ***,this study addresses the influence of mycorrhizal strategies on these foliar nutrients and their response to climate *** a new database was established including mycorrhizal types and leaf C_(mass),N_(mass),P_(mass),C:N and N:P of each plant species based on He et al.[(2008)leaf nitrogen:Phosphorus stoichiometry across Chinese grassland *** 155:301-10].the predomi-nant type of mycorrhizal association of each plant species was classified according to the published literature and our own *** analyzed leaf C_(mass),N_(mass),P_(mass),C:N and N:P among 112 plant species in 316 samples of ascertained mycorrhizal type in the major grassland biomes of *** Findingsthe results show highly significant variation among different myc-orrhizal strategy types for foliar C_(mass),N_(mass) and N:*** highest foliar C_(mass) was observed in ectotrophic mycorrhiza(ECM)type(469.8mg g1)followed by that in arbuscular mycorrhiza(AM)type(443.884 mg g1)and nonmycorrhizal(NM)type(434.0 mg g^(-1)).The foliar N concentration was significantly higher in NM type(31.0mg g^(-1)).However,the AM type had the greater C:N value(19)than the other types although less variation in C_(mass) and N:P among abuscular types on AM strategy was *** traits showed significant variation in response to precipita-tion(mean growing season and annual precipitation(GSP and MAP))and temperature(mean growing season and annual tem-peratures(GST and MAT))depending on different mycorrhizal strategies and arbuscular *** the responses of all folia parameters to precipitation and temperature were compared,the influence of GSP on leaf traits was greater than the influence of GST.

关键词： mycorrhizal strategy arbuscular type foliar traits precipitation temperature

Recent developments in high-strength Mg-RE-based alloys:Focusing on Mg-Gd and Mg-Y systems

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Journal of Magnesium and Alloys 2018年第3期6卷 277-291页

作者： Jinghuai Zhang Shujuan Liu Ruizhi Wu Legan hou Milin Zhang Key Laboratory of Superlight Material and Surface Technology Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001PR China Department of Materials Physics and Chemistry Harbin Institute of TechnologyHarbin 150001PR China College of Science Heihe UniversityHeihe 164300PR China

Higher strength is always the goal pursued by researchers for the structural materials,especially for the lightweight magnesium(Mg)alloys which generally have relatively low strength at *** this aspect,the present paper reviews the recent reports of a kind of Mg alloys,***-RE(RE:rare earths,mainly Gd or Y)casting and wrought alloys,which have been able to achieve high strength compared with common or commercial Mg alloys,from the viewpoint and content of the alloy system,alloying constitution,preparation process,tensile strength and each of the main strengthening *** review of recent research and developments in high-strength Mg-RE alloys is beneficial for the further design of Mg alloys with higher strength as well as excellent comprehensive performance.

关键词： Mg alloys High strength Rare earths(RE) Strengthening mechanism

Attenuated Listeria monocytogenes as a cancer vaccine vector for the delivery of CD24, a biomarker for hepatic cancer stem cells

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Cellular & Molecular Immunology 2014年第2期11卷 184-196页

作者： Yu yang Jiajie hou Zhe Lin Han Zhuo DianyuChen Xudong Zhang Yun Chen Beicheng Sun Liver Transplantation Center The First Affiliated Hospital of Nanjing Medical University Nanjing China and Nanjing Medical University Nanjing China

Attenuated Listeria monocytogenes （LM） is a promising candidate vector for the delivery of cancer vaccines. After phagocytosis by antigen-presenting cells, this bacterium stimulates the major histocompatibility complex （MHC）-I and MHC-II pathways and induces the proliferation of antigen-specific T lymphocytes. A new strategy involving genetic modification of the replication-deficient LM strain AdalAdat （Lmdd） to express and secrete human CD24 protein has been developed. CD24 is a hepatic cancer stem cell biomarker that is closely associated with apoptosis, metastasis and recurrence of hepatocellular carcinoma （HCC）. After intravenous administration in mice, Lmdd-CD24 was distributed primarily in the spleen and liver and did not cause severe organ injury. Lmdd-CD24 effectively increased the number of interferon （IFN）-7-producing CD8＋ T cells and IFN-7 secretion. Lmdd-CD24 also enhanced the number of IL-4- and IL-lO-producing T helper 2 cells. The efficacy of the Lmdd-CD24 vaccine was further investigated against Hepa1- 6-CD24 tumors, which were inguinally inoculated into mice. Lmdd-CD24 significantly reduced the tumor size in mice and increased their survival. Notably, a reduction of T regulatory cell （Treg） numbers and an enhancement of specific CD8＋ T-cell activity were observed in the tumor-infiltrating lymphocytes （TILs）. These results suggest a potential application of the Lmdd-CD24 vaccine against HCC.

关键词： cancer stem cell CD24 hepatocellular carcinoma immunotherapy Listeria monocytogenes

Exploration of nano-surface chemistry for spectral analysis

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Chinese Science Bulletin 2013年第18期58卷 2017-2026页

作者： LI ChengHui LIU Rui Lü Yi hou XianDeng WU Peng College of Chemistry Sichuan University Analytical & Testing Center Sichuan University

The applications of nano-surface chemistry in the field of spectral analysis have attracted growing interest in recent *** this article,we reviewed the applications of nanomaterials-based chemical reactions for spectral analysis,including the development in plasma-catalysis,surface-enhanced spectroscopy,separation and preconcentration,chemical vapor generation,labeling and signal *** of nano-surface chemistry to spectral analysis not only improves the sensitivity and selectivity,broadens the application range of spectral analysis,but also affords analytical community special characterization tools.

关键词：纳米材料光谱分析表面化学频谱分析等离子体催化化学领域化学反应表面增强

Key technique research on desktop virtualization in cloud environment

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International Journal of Modeling, Simulation, and Scientific Computing 2017年第2期8卷 232-240页

作者： Zhuohui Shen Liqin Guo Baocun hou Hongyan Quan ShuangShuang Zhou College of Computer Science and Software Engineering East China Normal University P.R.China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering P.R.China Beijing Aerospace Smart Manufacturing Technology Development Co.Ltd P.R.China

Desktop Virtualization is an essential problem in cloud manufacturing to make full use of shared resources so as to meet the practical application *** this paper,an efficient virtualization solution for desktop transferring is presented for sharing *** strategy is not limited to transfer desktops between virtual machines(VMs),transmission between virtual and physical machines is also achieved.A three-layer systemic structure based on web environment is proposed in the *** employ the application program library Libvirt and kernel-based virtual machine(KVM)technique to manage VMs with dynamic customization scheme,which gains better virtualization per***,we present two different schemes for desktop graphics *** is based on the transport protocol virtual network computing(VNC),and the other adopts the simple protocol for independent computing environment(SPICE),which both achieve more satisfactory *** validity of our scheme is demonstrated on some experimental results and systemic qualitative evaluation is also provided.

关键词： Virtualization KVM VNC VM SPICE.

Degradation induces changes in the soil C:N:P stoichiometry of alpine steppe on the Tibetan Plateau

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Journal of Mountain Science 2019年第10期16卷 2348-2360页

作者： ZHANG Zhen-chao hou Ge LIU Miao WEI Tian-xing SUN Jian School of Soil and Water Conservation Beijing Forestry UniversityBeijing100083China Synthesis Research Centre of Chinese Ecosystem Research Network Key Laboratory of Ecosystem NetworkObservation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy ofSciencesBeijing100101China State Key Laboratory of Urban and Regional Ecology Research Center for Eco–environmental SciencesChineseAcademy of SciencesBeijing100085China Department of Ecology Evolutionand Natural ResourcesSchool of Environmental and Biological SciencesRutgersUniversityNew BrunswickNew Jersey08901USA

Due to the Tibetan Plateau’s unique high altitude and low temperature climate conditions,the region’s alpine steppe ecosystem is highly fragile and is suffering from severe degradation under the stress of increasing population,overgrazing,and climate *** soil stoichiometry,a crucial part of ecological stoichiometry,provides a fundamental approach for understanding ecosystem processes by examining the relative proportions and balance of the three *** the impact of degradation on the soil stoichiometry is vital for conservation and management in the alpine steppe on the Tibetan *** study aims to examine the response of soil stoichiometry to degradation and explore the underlying biotic and abiotic mechanisms in the alpine *** conducted a field survey in a sequent degraded alpine steppe with seven levels inNorthern *** plant species,aboveground biomass,and physical and chemical soil properties such as the moisture content,temperature,pH,compactness,total carbon(C),total nitrogen(N),and total phosphorus(P)were measured and *** results showed that the contents of soil C/N,C/P,and N/P consistently decreased along intensifying degradation *** regression analysis and a structural equation model(SEM),we found that the C/N,C/P,and N/P ratios were positively affected by the soil compactness,soil moisture content and species richness of graminoids but negatively affected by soil pH and the proportion of aboveground biomass of *** soil temperature had a negative effect on the C/N ratio but showed positive effect on the C/P and N/P *** current study shows that degradation-induced changes in abiotic and biotic conditions such as soil warming and drying,which accelerated the soil organic carbon mineralization,as well as the increase in the proportion of forbs,whichwere difficult to decompose and input less organic carbon into soil,resulted in the decreases in soil C/N,C/P,and N/P contents to a great ex

关键词： Tibetan Plateau Alpine steppe Degradation Soil stoichiometry C/N C/P N/P

Anti-fertility effect of levonorgestrel and/or quinestrol on striped field mouse(Apodemus agrarius):evidence from both laboratory and field experiments

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Integrative Zoology 2022年第6期17卷 1041-1052页

作者： Xiaoning CHEN Xiang hou Tuo FENG Ning HAN Jing WANG Gang CHANG Shaanxi Key Laboratory for Animal Conservation Shaanxi Institute of ZoologyXi’anChina College of Life Sciences Shaanxi Normal UniversityXi’anChina

The effect of combined levonorgestrel(P)and quinestrol(E)on the fertility of stripedﬁeld mouse(Apodemus agrarius)has not been *** performed a series of experiments in both the laboratory andﬁeld to assess the effect of P and/or E on the fertility of *** the laboratory,to test the time-dependent anti-fertility ef-fects of P and E,as well as their mixtures,90 male stripedﬁeld mice were randomly assigned to 6 treatment groups(n=60),and a control group(n=30).Mice in 3 treatment groups were administered 1 of the 3 compounds(1 mg�kg–1[body weight]EP-1,0.34 mg�kg–1 E,0.66 mg�kg–1 P)for 3 successive days(another half for 7 suc-cessive days)via oral gavage;mice were then sacriﬁced 15 and 45 days after initiating the gavage ***ﬁndings indicated that E and EP-1 treatment,but not P or control treatment,signiﬁcantly decreased the sperm count in the caudal epididymis,as well as the weight of the testes,epididymides,and seminal ***,fer-tile female mice mated with E-and EP-1-treated males produced smaller *** data indicate that E and EP-1 can induce infertility in male *** theﬁeld,the population density of *** was signiﬁcantly inﬂu-enced by EP-1,and the rodent density in the treatment group was lower than that in the control ***,our results indicate that EP-1 is an effective contraceptive in ***,a dominant rodent species in the farmland.

关键词： Apodemus agrarius fertility control levonorgestrel quinestrol

Catalytic kinetics of dimethyl ether one-step synthesis over CeO_2–CaO–Pd/HZSM-5 catalyst in sulfur-containing syngas process

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Chinese Journal of Chemical Engineering 2016年第12期24卷 1735-1741页

作者： Ruizhi Chu Wenxin hou Xianliang Meng Tingting Xu Zhenyong Miao Guoguang Wu Lei Bai School of Chemical Engineering and Technology China University of Mining & Technology Xuzhou 221116 China High-Tech Research Institute of China University of Mining and Technology Lianyungang 222000 China Department of Chemical and Biomedical Engineering West Virginia University Morgantown 26506 USA

CeO_2–CaO–Pd/HZSM-5 catalyst was prepared for the dimethyl ether(DME) one-step synthesis in a continuous fixed-bed micro-reactor from the sulfur-containing syngas. The catalytic stability over hybrid catalyst of CeO_2–CaO–Pd/HZSM-5 was investigated to ensure that the kinetics experimental results were not significantly influenced by induction period and catalytic deactivation. A large number of kinetic data points(40 sets) were obtained over a range of temperature(240–300 °C), pressure(3–4 MPa), gas hourly space velocity(GHSV)(2000–3000 L·kg^(-1)·h^(-1)) and H_2/CO mole ratio(2–3). Kinetic model for the methanol synthesis reaction and the dehydration of methanol were obtained separately according to reaction mechanism and Langmuir–Hinshelwood mechanism. Regression parameters were investigated by the method combining the simplex method and Runge–Kutta method. The model calculations were in appropriate accordance with the experimental data.

关键词： CeO_2–CaO –Pd/HZSM-5 catalyst DME One-step synthesis Catalytic kinetics Sulfur-containing syngas

Landslides & Debris Flows Formation from Gravelly Soil Surface Erosion and Particle Losses in Jiangjia Ravine

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Journal of Mountain Science 2013年第6期10卷 987-995页

作者： HU Ming-jian PAN Hua-li WEI hou-zhen WANG Ren A Ying State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Gravelly soils are made up of gravel, sand, silt and clay. They are widely used in engineering applications such as rock-fill dams with clay cores, which are the main researches at present. The strength and mechanical properties of the gravelly soils are affected by the content of coarse grain, fine particles, and their adhesive states. These Properties can be verified by laboratory unconsolidated undrained triaxial tests with grain size less than 5 mm and by large scale direct-shear tests with original grain content. Fine particles of the loose gravelly slopes are released under rainfalls, alternated the structures and mechanical properties, even affected the slope stability. There are a series of large scale direct-shear tests with different coarse grain contents to study the influence of fine particles releasing and migration, results showed the strength behavior of the gravelly soils were affected by the coarse grain content （5） and the inflection coarse grain contents. In order to study the erosion features of the gravelly soil slopes on rainfall conditions and the slopes stability alteration, we had carried out one sort of artificial rainfall local and model experiments, the runoff sediment contents were monitored during the experiments. Result showed that the shapes of the slopes surface transformed periodically, runoff sediment contents were divided into five phases according to the experiment phenomena, runoff sediment contents maintained downtrend during the rain time and the downtrend was obviouslyinterpreted by one descend belt no matter the rainfall intensity and the slope angels. Particle size analysis released the deposit on the slope surface lost almost all of the clay, most of the silt and sand after the experiments, this meant the fine particles releasing, migration and accumulation process on condition of rainfall resulted in the instability factor of the slopes even induced landslide or debris flow.

关键词： Gravelly soils Erosion process Particlelosses Runoff sediment content JiangJia Ravine