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Diurnal dynamics of soil respiration and the influencing factors for three land-cover types in the hinterland of the Taklimakan Desert,China

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Journal of Arid Land 2017年第4期9卷 568-579页

作者： YANG Fan ALI Mamtimin ZHENG Xinqian HE Qing YANG Xinghua huo wen LIANG Fengchao wANG Shaoming Institute of Desert Meteorotogy China Meteorological AdministrationUrumqi 830002China Taklimakan Desert Atmosphere and Environment Observation Experiment Station Tazhong 841000China Xinjiang Agro-Meteorological Observatory Urumqi 830002China Xinjiang Climate Center Urumqi 830002China Forestry Bureau of Bailongjiang Lanzhou 730050China

Knowledge of soil respiration and the influencing factors in desert ecosystems is essential to understanding carbon dynamics and responses of biotic and abiotic processes in soils to climate change. In this study, soil respiration rate（R_s） for three land-cover types（shifting sandy land, sandy land with straw checkerboard barriers, and shelter forest land） in the hinterland of the Taklimakan Desert was measured in May 2015 using an automated soil CO_2 flux system. The effects of soil temperature（T_s） and soil water content（w_s） on R_s were also analyzed. The results showed that R_s values in shifting sandy land, sandy land with straw checkerboard barriers, and shelter forest land were all low and exhibited obvious diurnal fluctuations. The establishment of straw checkerboard barriers in sandy land had no significant effect on R_s, while the establishment of shelterbelts significantly increased R_s. Shifting sandy land and sandy land with straw checkerboard barriers were carbon sinks at night and early morning and were carbon sources in the daytime, while shelter forest land always acted as a carbon source during the whole day. The synergistic effect of T_s and w_s could better explain the diurnal dynamics in R_s than single factor. In shifting sandy land and sandy land with straw checkerboard barriers, w_s was identified as a limiting factor influencing the diurnal dynamics of R_s. Furthermore, a relatively strong hysteresis loop existed between R_s and T_s. In contrast, in shelter forest land, R_s was significantly influenced by T_s, and a relatively weaker hysteresis loop existed between R_s and w_s.

关键词： soil respiration soil temperature soil water content hysteresis effect Taklimakan Desert

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抗炎合剂通过调控Beclin-1介导自噬减轻大鼠脓毒症急性肺损伤

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中华危重病急救医学 2024年第7期36卷 717-722页

作者：陆玮兰闫国良沈一凡李海涛吴赛翁同锐张蕊火艳雯上海中医药大学附属市中医医院重症医学科上海200071

目的探讨抗炎合剂对脓毒症急性肺损伤(ALI)大鼠的保护作用及其可能机制。方法将40只SD大鼠按随机数字表法分为假手术组、脓毒症ALI模型组(模型组)、3-甲基腺嘌呤(3-MA)对照组、抗炎合剂预处理组,每组10只。采用盲肠结扎穿孔术(CLP)建立... 详细信息

目的探讨抗炎合剂对脓毒症急性肺损伤(ALI)大鼠的保护作用及其可能机制。方法将40只SD大鼠按随机数字表法分为假手术组、脓毒症ALI模型组(模型组)、3-甲基腺嘌呤(3-MA)对照组、抗炎合剂预处理组,每组10只。采用盲肠结扎穿孔术(CLP)建立脓毒症ALI大鼠模型;假手术组仅开腹、关腹,不给予穿孔结扎;两组均于术前连续3 d给予生理盐水灌胃和腹腔注射。3-MA对照组于制模前连续3 d给予生理盐水和自噬抑制剂3-MA 15 mg/kg腹腔注射。抗炎合剂预处理组于制模前连续3 d给予抗炎合剂8.8 mL/kg灌胃〔抗炎合剂组成:大黄15 g(后下)、黄连15 g、黄芩12 g、厚朴12 g、败酱草30 g〕,并腹腔注射生理盐水。各组于术后24 h取大鼠腹主动脉血处死,采用酶联免疫吸附试验(ELISA)检测血清炎症细胞因子白细胞介素(IL-1β、IL-6)水平。取肺组织,收集支气管肺泡灌洗液(BALF),采用ELISA法检测IL-1β、IL-6水平;检测肺湿/干质量(w/D)比值;苏木素-伊红(HE)染色后,光镜下观察肺组织病理学改变;采用蛋白质免疫印迹试验(western blotting)检测肺组织自噬标志物微管相关蛋白1轻链3-Ⅱ/Ⅰ(LC3-Ⅱ/Ⅰ)和Beclin-1蛋白表达;透射电镜下观察肺组织自噬小体。结果与假手术组比较,模型组大鼠肺组织结构破坏严重,有大量炎症细胞浸润,肺w/D比值、血清和BALF中IL-1β、IL-6水平均明显升高,LC3-Ⅱ/Ⅰ比值和Beclin-1蛋白表达均明显下调,自噬小体明显增加。3-MA对照组大鼠肺组织损伤程度较模型组更严重,肺w/D比值和血清、BALF中炎症细胞因子水平进一步升高,肺组织LC3-Ⅱ/Ⅰ比值和Beclin-1蛋白表达仍较假手术组呈下调趋势,自噬小体较模型组减少。与模型组相比,抗炎合剂预处理组大鼠肺组织损伤明显减轻,少量炎症细胞浸润,肺w/D比值明显降低(7.07±1.02比11.33±1.85,P<0.05),血清和BALF中IL-1β、IL-6水平均明显下降〔IL-1β(ng/L):血清为26.04±3.86比40.83±5.46,BALF为17.75±2.02比26.86±4.32;IL-6(ng/L):血清为91.28±10.15比129.44±13.05,BALF为76.06±7.51比120.91±7.47,均P<0.05〕,肺组织LC3-Ⅱ/Ⅰ比值和Beclin-1蛋白表达显著上调〔LC3-Ⅱ/Ⅰ比值:1.23±0.02比0.60±0.02,Beclin-1蛋白(Beclin-1/GAPDH):2.37±0.33比0.62±0.05,均P<0.05〕,且自噬小体数量明显增加。结论抗炎合剂能改善CLP致脓毒症大鼠肺损伤,降低炎症水平,其机制可能与通过上调Beclin-1表达介导自噬有关。

关键词：脓毒症急性肺损伤抗炎合剂炎症因子自噬

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Inactivation of Antinutritive Factors in Soya Bean by Proteolytic Enzymes

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Journal of Northeast Agricultural University(English Edition) 1998年第2期5卷 128-137页

作者： huo Guichen, Yang Lijie (Northeast Agricultural University, Harbin 150030, P R C)

The capacity of five enzymes (P1-P5) to inactivate the trypsin inhibitory activity (TIA) and lectin in raw soybean (RS) and low temperature-extruded soybean (LTES) was examined. P1 is an acid fungal protease with pH optimum of 5 and P2, P3, P4 and P5 are bacterial proteases with pH optima of 7, 10, 8 and 8 respectively. The results indicated that all enzymes could reduce TIA to a varying degree at their optimum pH. The sequence of effectiveness was P3>P4>P5>P1>P2. The most effective enzyme, P3, reduced TIA to 38% and chymotrypsim inhibitory activity (CIA) to 9% of the original values. After six hours incubation at 50℃, the lectin concentration of LTES and RS was reduced by 50 and 17% respectively by P3, and by 42 and 29% by P4. In the second study, the best enzymes, P3 and P4, were incubated with RS or LTEs at different doses of 0, 0.10, 0.50% or 1.00% (w/w), for periods of 1, 2, 3, 6 or 12 hours. After one hour incubation with P3 at 1.00%, TIA of RS was reduced from 36.60 to 13.30 mg·g -1 . The corresponding values for LTES were 24.50 and 1.90 mg·g -1 . when the incubation was extended to 12 hours, the remaining TIA was 0.90 for LTES and 1.20 mg·g -1 for RS. P4 was not as effective as P3 up to six-hour incubation, but after twelve hours it achieved a similar reduction in activity to that of P3. A kinetic analysis of data showed that the inactivation process of purified soyabean trypsin inhibitors by P3 followed first-order chemical kinetics (Ct=90.90 -0.0408t , r=0.99). The rate of denaturation was -0.0408 per minute. It is concluded that the use of selected enzymes for anti-nutritive factors (ANFs) is an exciting possibility, but still requires further development.

关键词： soybean protease protease inhibitors lectin,enzymatic inactivation

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汉语发展性阅读障碍临床诊断实践

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中华儿科杂志 2024年第6期62卷 548-552页

作者：刘钟泠霍言言陈艳妮池霞张媛媛董传菲吴丹刘诗雨朱江陈津津上海交通大学医学院附属儿童医院儿童保健科上海200062 西安交通大学附属儿童医院儿童保健中心西安710003 南京市妇幼保健院儿童保健科南京210004

目的探讨引入标准化评估工具对汉语发展性阅读障碍(DD)临床诊断的优化作用。方法采用横断面研究,于2023年5至12月从上海交通大学医学院附属儿童医院儿童保健科门诊招募130名存在语文成绩明显落后临床表现且筛查性量表筛查阳性的小学一... 详细信息

目的探讨引入标准化评估工具对汉语发展性阅读障碍(DD)临床诊断的优化作用。方法采用横断面研究,于2023年5至12月从上海交通大学医学院附属儿童医院儿童保健科门诊招募130名存在语文成绩明显落后临床表现且筛查性量表筛查阳性的小学一至三年级儿童作为研究对象。筛查性量表采用中国小学生阅读障碍行为筛查量表(CDSBC),以儿童汉语阅读障碍筛查量表作为辅助。参照“汉语发展性阅读障碍诊断与干预的专家意见”的标准流程,对研究对象使用现代汉语发展性读写障碍评估工具(DDSSM)进行读写相关认知能力评价及诊断性评估,分为学习落后表现组和DD组。采用t检验和χ^(2)检验对比两组在智力、读写能力和注意缺陷多动障碍分布方面的差异。采用Spearman相关性分析分析DDSSM中各项认知能力得分与CDSBC得分的相关性。结果130名研究对象中男90名,年龄(8.3±1.0)岁;女40名,年龄(8.1±0.9)岁。最终诊断DD 59例,其中男41例。学习落后表现组与DD组的操作智商差异无统计学意义(101±15比100±15,t=0.53,P>0.05),DDSSM中字词读写能力差异有统计学意义(32±5比21±4,t=11.56,P0.05]。DDSSM中口语词汇量、语素意识和正字法意识与CDSBC总分均负相关(r=-0.42、-0.32、-0.35,均P0.05)。结论针对读写相关认知能力,CDSBC的评估作用不足,因此引入标准化DDSSM是对汉语DD临床诊断的优化,对实现精准诊断和干预具有至关重要的作用。

关键词：儿童阅读障碍行为评定量表诊断

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土水肥耦合下五叶地锦光合日变化特征

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林业科技 2024年第5期49卷 11-18页

作者：霍娜赵迎雪杨新兵刘小宽李新月河北农业大学林学院河北保定071000 易县自然资源和规划局河北保定071000

矿山岩质边坡植被恢复困难,为探究土水肥耦合对五叶地锦光合特征的影响,试验地点选在石家庄市鹿泉区一废弃石灰岩采石场,以五叶地锦幼苗为研究对象,采用L_(16)(4)^(5)正交表进行3因素4水平设计,测定其光合指标及光合有效辐射(PAR)、温度... 详细信息

矿山岩质边坡植被恢复困难,为探究土水肥耦合对五叶地锦光合特征的影响,试验地点选在石家庄市鹿泉区一废弃石灰岩采石场,以五叶地锦幼苗为研究对象,采用L_(16)(4)^(5)正交表进行3因素4水平设计,测定其光合指标及光合有效辐射(PAR)、温度(Ta)、空气相对湿度(RH)、大气CO_(2)浓度(Ca)等环境因子日变化参数,分析土水肥耦合下五叶地锦光合特征与环境因子的关系。结果表明:(1)Pn、E、wUE值在w_(1)N_(1)耦合下与同一土层厚度下的其他处理存在差异,随着土层厚度增加,水分减少,Pn、E、wUE、gs值减小;(2)Pn、wUE、CO_(2)值在S_(1)N_(1)耦合下与同一水分条件下的其他处理存在差异,随着水分减少,Pn、E减小,与土层厚度和施肥量无关,wUE、gs值在低土层厚度和高施氮耦合下增加,CO_(2)值在中度土层厚度和无氮肥耦合下增加。(3)Pn、wUE、gs、CO_(2)值在S_(1)w_(1)耦合与同一施氮条件下的其他处理存在差异,随着施肥量的增加,Pn、E、gs值在高土层厚度和高水分耦合下增加;wUE、Ci值在低土层厚度和低水分耦合下增加。(4)Pn、E、gs与PAR呈显著正相关;PAR与Ta、Ta与RH、Ca与RH呈显著相关。综合表明,合理的土水肥耦合能促进五叶地锦的生长及光合作用,且在S_(4)w_(1)N_(4)处理下耦合效果最佳。

关键词：五叶地锦土水肥耦合光合日变化环境因子

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Preparation and Corrosion Resistance of Magnesium Coatings by Magnetron Sputtering Deposition

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Journal of Materials Science & Technology 2003年第5期19卷 459-462页

作者： Hongwei huo, Ying LI and Fuhui wANGState Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Magnesium coatings were fabricated on stainless steel substrates (1Cr11Ni2w2MoV) by a plane magnetron sputtering technique. The argon pressure and the substrate condition (including temperature and the substrate was rotated or fixed) were varied in order to evaluate the influence of the parameters on the crystal orientation and morphology of the coating. The corrosion behavior of the coatings in 1 wt pct NaCI solution was studied by electrochemical methods. The results showed that all coatings exhibited preferred orientation (002) as the argon pressure increased from 0.2 to 0.4 Pa. The morphologies of the coatings varied with the argon pressure and with whether the substrate was rotated or fixed. The open circuit potential of the coatings was more positive than that of cast AZ91D magnesium alloy. However, the immersion test in 1 wt pct NaCI solution showed that the corrosion rates of the coatings were higher than that of cast AZ91D magnesium alloy.

关键词： Magnesium coating Corrosion Magnetron sputtering deposition

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Ecological functions of uncultured microorganisms in the cobaltrich ferromanganese crust of a seamount in the central Pacific are elucidated by fosmid sequencing

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Acta Oceanologica Sinica 2015年第4期34卷 92-113页

作者： huo Yingyi CHENG Hong Anton F.Post wANG Chunsheng JIANG Xiawei PAN Jie wU Min XU Xuewei Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of Oceanography State Oceanic Administration State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography College of Life Sciences Zhejiang University The Josephine Bay Paul Center for Comparative Molecular Biology and Evolution Marine Biology Laboratory State Key Laboratory for Diagnosis and Treatment of Infectious Diseases the First Affiliated Hospital School of Medicine Zhejiang University

Cobalt-rich ferromanganese is an important seafloor mineral and is abundantly present in the seamount crusts. Such crusts form potential hotspots for biogeochemical activity and microbial diversity, yet our understanding of their microbial communities is lacking. In this study, a cultivation-independent approach was used to recover genomic information and derive ecological functions of the microbes in a sediment sample collected from the cobalt-rich ferromanganese crust of a seamount region in the central Pacific. A total of 78 distinct clones were obtained by fosmid library screening with a 16S rRNA based PCR method. Proteobacteria and MGI Thaumarch-aeota dominated the bacterial and archaeal 16S rRNA gene sequence results in the microbial community. Nine fosmid clones were sequenced and annotated. Numerous genes encoding proteins involved in metabolic functions and heavy metal resistance were identified, suggesting alternative metabolic pathways and stress responses that are essential for microbial survival in the cobalt-rich ferromanganese crust. In addition, genes that participate in the synthesis of organic acids and exoploymers were discovered. Reconstruction of the metabolic pathways revealed that the nitrogen cycle is an important biogeochemical process in the cobalt-rich ferromanganese crust. In addition, horizontal gene transfer （HGT） events have been observed, and most of them came from bacteria, with some occurring in archaea and plants. Clone w4-93a, belonging to MGI Thaumarch-aeota, contained a region of gene synteny. Comparative analyses suggested that a high frequency of HGT events as well as genomic divergence play important roles in the microbial adaption to the deep-sea environment.

关键词： seamount cobalt-rich ferromanganese crust metagenome horizontal gene transfer

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隧道防水减震隔热一体化关键技术研究

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铁道标准设计 2024年第1期68卷 1-10页

作者：王复明郭成超孙博王浩然关欢刘建友霍建勋答子虔中山大学土木工程学院广州510275 西南交通大学土木工程学院成都610031 中铁工程设计咨询集团有限公司北京100055 中国铁路经济规划研究院有限公司北京100038

西部地区交通隧道建设面临全球最为复杂的工程地质条件。受高烈度地震带、富水环境与高低温带等不良地质影响,隧道震害、水害与冻热害问题突出,隧道防水减震隔热一体化技术研究需求迫切。为此,针对多致灾因素下的交通隧道安全建养问题... 详细信息

西部地区交通隧道建设面临全球最为复杂的工程地质条件。受高烈度地震带、富水环境与高低温带等不良地质影响,隧道震害、水害与冻热害问题突出,隧道防水减震隔热一体化技术研究需求迫切。为此,针对多致灾因素下的交通隧道安全建养问题开展系统研究。首先,在前期研发的新型韧性非水反应高聚物材料基础上,进行隧道防水阻渗、减震隔震与保温隔热相关技术研究,开展抗渗试验、减震试验和导热系数测定试验及仿真分析。研究表明,0.6 g/cm^(3)的高聚物材料抗渗等级达到10级,具有良好的防水性能;采用外包高聚物隔震层的隧道复合衬砌结构可减少36%地震波作用下的隧道变形;温度较低时,高聚物导热系数随密度增大而呈现增大趋势,密度每增加1 g/cm^(3),导热系数增大0.1709 w/(m·K),温度较高时,高聚物导热系数随密度增大而呈现先增大后减小趋势;进一步提出隧道“围岩-初衬-高聚物-二衬”复合式衬砌支护体系。最后,开展隧道高聚物防水减震隔热层喷涂施工物理模型试验与现场技术示范,给出最佳喷涂工艺参数,实现隧道防水-减震-隔热功能的一体化应用。相关研究成果可为高烈度、富水环境及高低温带交通隧道安全设计与施工提供借鉴。

关键词：隧道工程高聚物材料防水减震隔热复合式衬砌一体化技术技术示范

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Multifunctional metasurfaces enabled by simultaneous and independent control of phase and amplitude for orthogonal polarization states

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Light(Science & Applications) 2021年第6期10卷 1088-1098页

作者： Mingze Liu wenqi Zhu Pengcheng huo Lei Feng Maowen Song Cheng Zhang Lu Chen Henri JLezec Yanqing Lu Amit Agrawal Ting Xu National Laboratory of Solid-State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied SciencesNanjing University210093 NanjingChina Collaborative Innovation Center of Advanced Microstructures 210093 NanjingChina Physical Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20877USA Maryland NanoCenter University of MarylandCollege ParkMD 20877USA School of Optical and Electronic Information and wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology430074 WuhanChina

Monochromatic light can be characterized by its three fun dame ntal properties:amplitude,phase,and *** this work,we propose a versatile,transmission-mode all-dielectric metasurface platform that can independently manipulate the phase and amplitude for two orthogonal states of polarization in the visible frequency *** proof-o仁concept experimental demonstration,various single-layer metasurfaces composed of subwavelength-spaced titanium-dioxide nanopillars are designed,fabricated,and characterized to exhibit the ability of polarization-switchable multidimensional light-field manipulation,including polarization-switchable grayscale nanoprinting,nonuniform cylindrical lensing,and complex-amplitude *** envision the metasurface platform dem on strated here to open new possibilities toward creating compact multifunctional optical devices for applications in polarization optics,information encoding,optical data storage,and security.

关键词： phase proof simultaneous

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Tungsten removal from molybdate solutions using chelating ion-exchange resin:Equilibrium adsorption isotherm and kinetics

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Journal of Central South University 2016年第5期23卷 1052-1057页

作者：朱先正霍广生倪捷宋琼 School of Metallurgy and Environment Central South University

The equilibrium adsorption isotherm and kinetic of the sorption process for w and Mo on macro chelating resin D403 were investigated on single Na2 Mo O4 and Na2wO4 *** sorption isotherm results show that the adsorption process of w obeys the Freundlich model very well whereas the exchange process with Mo approximately follows the Henry *** kinetic experiments show that the intraparticle diffusion process was the rate-determining step for w sorption on the resin,and the corresponding activation energy is calculated to be 21.976 k J/mol.

关键词： tungsten molybdate ion-exchange resin isotherms kinetics

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