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Effects of grazing disturbance of spatial distribution pattern and interspecies relationship of two desert shrubs

Journal of Forestry Research 2022年第2期33卷 507-518页

作者： Lei Zhang Yong Gao Jinrong Li Chao Zhang Minyu Li zhao hu Xiangxin Cui College of Desert Science and Engineering Inner Mongolia Agricultural UniversityHohhot 010019People’s Republic of China Institute of Water Resources for Pastoral Area of the Ministry of Water Resources Hohhot 010020People’s Republic of China Institute of Forestry Monitoring and Planning of Inner Mongolia Autonomous Region Hohhot 010020People’s Republic of China School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083People’s Republic of China

Grazing significantly affects the distribution,growth,and productivity of *** this study,we evalu-ated the effects of grazing disturbance on the spatial distri-bution patterns and interspecific relationships of two desert shrubs,Ammopiptanthus mongolicus and Sarcozygium *** types of grazing conditions were considered,including enclosed area(EA),seasonal rotational grazing area(SRGA),and grazing area(GA)(100 m×100 m),in the West Ordos Nature Reserve of Inner Mongolia,*** results showed that *** and *** populations were uniformly distributed at a small scale,and the distribution in EA and SRGA became gradually *** GA,*** population showed aggregated distribution but *** population showed random distribution at a small scale. Moreover, both A. mongolicus and S. xanthoxylon populations at the 5-7 m scale showed random distribution. At the small and intermediate scales, the two species showed positive interspecific relationships of GA. However, no interspecific relationship was noted between the two species in EA and SRGA. A significant positive relationship (P < 0.01) was noted between the two species at 2-9 m and a negative relationship (P < 0.01) at 13-17 m scales in GA. Positive relationship (P < 0.01) was noted between the two species at 6-13 m scales and a sig-nificant negative relationship (P < 0.01) at 14-24 m scales in SRGA. The two species of desert shrubs showed posi-tive interspecific relationships at the small scale, and they showed negative relationships as the interspecific compe-tition intensified in the presence of grazing disturbance. When the grazing intensity exceeds a certain threshold, the interspecific relationships become weak. Therefore, moder-ate grazing would facilitate interspecific competition and species succession, whereas excessive grazing would disrupt natural competition causing desertification ultimately.

关键词： Extending point pattern analysis Grazing Interspecific relationships Unmanned aerial vehicle(UAV)

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Exploring the influence of environmental factors in partitioning evapotranspiration along an elevation gradient on Mount Gongga, eastern edge of the Qinghai-Tibet Platea, China

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Journal of Mountain Science 2020年第2期17卷 384-396页

作者： SUN Ju-ying SUN Xiang-yang hu zhao-yong WANG Gen-xu Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Evapotranspiration(ET) is a crucial part of the global hydrological cycle, and quantifying ET components is significant for understanding the global water cycle and energy balance. However, there is no consensus on the value of ET components, especially in topographic abrupt change zone, such as eastern margin of the Qinghai-Tibet Platea, where values of ET changes along the altitudinal gradients. Our aim is to explore the influencing factors in partitioning evapotranspiration and how ET components change with increasing elevations. A novel approach was proposed to estimate ET components by adding net solar radiation(Rn) instead of the vapor pressure deficit(VPD) into the underlying water use efficiency(u WUE) model based on one-year continuous measurements of flux data along the elevation gradient on Mount Gongga. Correlation analysis shows that the u WUE model's performance can be improved significantly by considering Rn instead of VPD, with correlation coefficients increasing by 35%-64%. The ratios of transpiration(T) to ET(T/ET) were 0.47, 0.48, 0.50 and 0.35 for the deciduous broadleaf forest(BF), mixed coniferous and deciduous broadleaf forest(MF), evergreen needle forest(ENF) and shrub land(SL), respectively. Leaf area index(LAI) and air temperature(Ta) were the two main controlling factors in determining T/ET during the growing season and at an annual scale, while Rn and Ta played more important roles during the dormant season. This study highlights the importance of incorporating Rn in partitioning evapotranspiration by using the water use efficiency(WUE) method in a humid mountainous region, which can improve the estimation of T/ET on a global scale.

关键词： Eddy covariance Water use efficiency Radiation Evapotranspiration components

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老年住院患者临床分离真菌的分布特点与药敏分析

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老年医学与保健 2024年第1期30卷 221-227页

作者：王粟肖淑珍赵虎韩立中复旦大学附属华东医院检验科上海200040 上海交通大学医学院附属瑞金医院检验科上海200025 上海交通大学医学院附属瑞金医院临床微生物科上海200025

目的探讨老年住院患者临床分离的真菌菌种分布特点及其耐药特征,为老年抗真菌感染的防控与诊疗提供参考。方法收集2022年1月至12月上海某三甲医院年龄≥60岁、且真菌培养阳性的住院患者的临床样本、以及患者性别、年龄等临床信息,采用... 详细信息

目的探讨老年住院患者临床分离的真菌菌种分布特点及其耐药特征,为老年抗真菌感染的防控与诊疗提供参考。方法收集2022年1月至12月上海某三甲医院年龄≥60岁、且真菌培养阳性的住院患者的临床样本、以及患者性别、年龄等临床信息,采用念珠菌筛选培养基进行分离培养,MALDI-TOF MS进行菌种鉴定,ATB FUNGUS 3进行两性霉素B(AMB)、氟康唑(FCA)、伊曲康唑(ITR)、伏立康唑(VRC)、5-氟胞嘧啶(5FC)的体外药敏试验。结果本研究在60~104岁住院患者中检出1632株真菌,男性(997/1632,61.09%)多于女性,70~79岁患者最多(569/1632,34.87%),科室来源最多为ICU(720/1632,44.12%)。检出前4位均为念珠菌(1596/1632,96.38%),白念珠菌分离率最高(906/1632,55.51%),其次为光滑念珠菌(350/1632,21.45%)、热带念珠菌(194/1632,11.89%)和近平滑念珠菌(123/1632,7.54%)。主要念珠菌对AMB与5FC的耐药率在0~2.86%;白念珠菌对另外3种唑类药物的耐药率低于15%;光滑念珠菌对ITR耐药率高达42.86%;热带念珠菌对ITR耐药率最高(61.34%),对VRC和5FC耐药率均>50%;4种主要念珠菌的患者以男性居多,不同性别的耐药率均无统计学差异(P>0.05)。另外有247株念珠菌对3种唑类药物全耐药,检出比例以热带念珠菌最高(99/194,51.03%)。结论ICU应更加重视老年住院患者院内真菌感染的发生与预防。白念珠菌仍是主要分离菌种,但光滑和热带念珠菌的检出比例升高,以及对唑类药物较高的耐药率也应引起临床注意。定期的真菌药敏监测仍然是必要举措。

关键词：真菌念珠菌老年耐药性

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“互联网+”背景下基于“雨课堂”的食品质量管理学改革探讨

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创新创业理论研究与实践 2024年第4期7卷 15-18页

作者：石潇瀑兰伟耿秀婷赵胡阜阳师范大学生物与食品工程学院安徽阜阳236037

“互联网+”是依托互联网信息技术实现互联网与其他产业的联合,“互联网+教育”是提高高校课程教学质量的现代化途径。食品质量管理学是食品质量与安全本科专业的主干课程,其内容复杂导致现有教学方式不能有效传授。该文就应用智慧教学... 详细信息

“互联网+”是依托互联网信息技术实现互联网与其他产业的联合,“互联网+教育”是提高高校课程教学质量的现代化途径。食品质量管理学是食品质量与安全本科专业的主干课程,其内容复杂导致现有教学方式不能有效传授。该文就应用智慧教学工具“雨课堂”开展食品质量管理学课程改革进行探讨:在课程资源建设、教学内容设置、教学活动安排、教学环节优化方面,“雨课堂”有助于食品质量管理学教学活动的高效开展。

关键词： “互联网+” 教育 “雨课堂” 食品质量管理学改革以学生为中心

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基于TBL的博士生高级局部解剖选修课教学改革探究

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中国高等医学教育 2024年第2期 67-69页

作者：彭会明刘子建肖海涛赵虎华中科技大学同济医学院基础医学院湖北武汉430030

为了进一步提升博士生的高级局部解剖学选修课的教学质量,加强专业课程建设,开展基于TBL的教学改革。选课的博士生首先根据专业分成4个大组,每大组再分成3~4个小组。通过教师专题讲座、分组讨论和解剖操作,提高学员们的学习积极性,使其... 详细信息

为了进一步提升博士生的高级局部解剖学选修课的教学质量,加强专业课程建设,开展基于TBL的教学改革。选课的博士生首先根据专业分成4个大组,每大组再分成3~4个小组。通过教师专题讲座、分组讨论和解剖操作,提高学员们的学习积极性,使其学习目的性更明确。通过学生问卷调查和非任课教师的课堂评估,反映出博士生对教学模式和内容的满意度较高,学习效果好。

关键词：局部解剖学博士生选修课团队为中心的学习

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共点多极化电磁法对复杂地形条件下隧道断层的识别

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勘察科学技术 2024年第1期 52-56页

作者：赵虎刘卓徐勇谭建秋张泉四川省公路规划勘察设计研究院有限公司成都市610041

该文介绍了采用一种新型大地电磁方法—多极化大地电磁法,对复杂地形条件下的隧道进行勘察。该方法采用空间共点多极化同频观测方法,有效压制了静态效应,提高了山区大地电磁的勘探效率,改善了探测断层的准确度。在西昌至香格里拉高速新... 详细信息

该文介绍了采用一种新型大地电磁方法—多极化大地电磁法,对复杂地形条件下的隧道进行勘察。该方法采用空间共点多极化同频观测方法,有效压制了静态效应,提高了山区大地电磁的勘探效率,改善了探测断层的准确度。在西昌至香格里拉高速新山隧道工程应用中,该方法对隧道多处断裂构造位置及地质特征反映准确快速,为后续隧道设计及地勘工作起到了较好的指导作用,表明多极化大地电磁法,在复杂地形条件下的隧道断层识别中,具有较好的效果。

关键词：多极化大地电磁法复杂地形隧道断层

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海马-杏仁核脑深部电刺激术治疗难治性内侧颞叶癫痫长期疗效及其对认知功能的影响

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中国现代神经疾病杂志 2024年第7期24卷 540-546页

作者：苏乐王健赵虎林凌至培王湘庆崔志强华北理工大学临床医学院研究生院唐山063000 解放军总医院第一医学中心神经外科医学部北京100853 解放军总医院海南医院神经外科三亚572013 解放军总医院第一医学中心神经内科医学部北京100853

目的探讨海马-杏仁核脑深部电刺激术(AH-DBS)治疗难治性内侧颞叶癫痫的长期疗效及其对认知功能的影响。方法共纳入2014年1月至2018年12月解放军总医院第一医学中心收治的7例难治性内侧颞叶癫痫患者,均行AH-DBS,对比手术前后癫痫发作... 详细信息

目的探讨海马-杏仁核脑深部电刺激术(AH-DBS)治疗难治性内侧颞叶癫痫的长期疗效及其对认知功能的影响。方法共纳入2014年1月至2018年12月解放军总医院第一医学中心收治的7例难治性内侧颞叶癫痫患者,均行AH-DBS,对比手术前后癫痫发作形式、发作频率和抗癫痫发作药物应用情况,采用韦氏成人智力量表修订版(WAIS-R)评估认知功能;术后记录刺激参数以及手术相关并发症。结果共7例患者行双侧AH-DBS 4例,左侧AH-DBS 2例,左侧AH-DBS联合右侧颞前叶切除术1例;经枕部入路6例,经额部入路1例;仅1例患者术后出现头皮切口愈合不良,经局部植皮后痊愈。术后平均随访(73.00±8.98)个月,随访期间复杂部分性发作频率[1.00(0.00,31.00)次/月对2.00(1.50,60.00)次/月;Z=-2.207,P=0.027]、继发性全面性强直-阵挛发作频率[0.00(0.00,1.00)次/月对2.00(1.00,3.00)次/月;Z=-2.428,P=0.015]和总发作频率[1.00(0.50,31.00)次/月对5.00(2.50,64.00)次/月;Z=-2.366,P=0.018]均较术前减少,而手术前后抗癫痫发作药物种类[1.00(1.00,2.00)种对1.00(1.00,3.00)种;Z=-1.633,P=0.102]和WAIS-R评分[(85.50±7.09)分对(89.00±9.47)分;t=-1.761,P=0.078]差异无统计学意义。结论 AH-DBS作为一种新型抗癫痫治疗方法,可以减少难治性内侧颞叶癫痫发作频率,无严重不良事件,且对认知功能无明显影响。

关键词：癫痫颞叶深部脑刺激法海马杏仁核认知

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Development of three Drosophila melanogaster strains with different sensitivity to volatile anesthetics

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Chinese Medical Journal 2009年第5期122卷 561-565页

作者： LIU Jin hu zhao-yang YE Qi-quan DAI Shuo-hua Department of Anesthesiology West China Hospital Sichuan University Chengdu Sichuan 610041 China State Key Laboratory of Biotherapy of Cancer Chengdu Sichuan 610041 China Department of Life Science Peking University Beijing 100871 China

Background The mechanisms of action for volatile anesthetics remain unknown for centuries partly owing to the insufficient or ineffective research models. We designed this study to develop three strains derived from a wild-type Drosophila melanogaster with different sensitivities to volatile anesthetics, which may ultimately facilitate molecular and genetic studies of the mechanism involved. Methods Median effective doses （ED50） of sevoflurane in seven-day-old virgin female and male wild-type Drosophila melanogaster were determined. The sensitive males and females of percentile 6-10 were cultured for breeding sensitive offspring （$1）. So did median ones of percentile 48-52 for breeding median offspring （M1）, resistant ones of percentile 91-95 for breeding resistant offspring （R1）. Process was repeated through 31 generations, in the 37th generation, S37, M37 and R37 were used to determine ED5o for enflurane, isoflurane, sevoflurane, desfiurane, halothane, methoxyflurane, chloroform and trichloroethylene, then ED50 values were correlated with minimum alveolar concentration （MAC） values in human. Results From a wild-type Drosophila melanogaster we were able to breed three strains with high, median and low sevoflurane requirements. The ratio of sevoflurane requirements of three strains were 1.20：1.00：0.53 for females and 1.22：1.00：0.72 for males. Strains sensitive, median and resistant to sevoflurane were also sensitive, median and resistant to other volatile anesthetics. For eight anesthetics, ED50 values in three strains correlated directly with MAC values in human. Conclusions Three Drosophila melanogaster strains with high, median and low sensitivity to volatile anesthetics, but with same hereditary background were developed. The ED50 are directly correlated with MAC in human for eight volatile anesthetics.

关键词： drosophila melanogaster sensitivity median effective doses volatile anesthetics sevoflurane

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Analysis of Spatio-Temporal Changes of Land Usein Xuzhou City Based on Remote Sensing

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Journal of China University of Mining and Technology 2006年第2期16卷 151-155页

作者： hu zhao-ling DU Pei-jun GUO Da-zhi School of Urban and Environmental Science Xuzhou Normal University Xuzhou Jiangsu 221116 China School of Environmental Sciences and Spatial lnformatics. China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Based on the satellite remote sensing TM/ETM images of Xuzhou city, basic data about land use of the city from 1994 to 2000 are obtained with the neural network classification module of PCI software, and the dynamic con- version matrix of land use is thus calculated. The areas of construction land and water body have increased by 1833.93 hm2 and 804.87 hm2, respectively. On the contrary, the area of cropland has decreased by 3207.24 hm2. The area of cropland converted into construction land makes up 26.84%, and that converted into water body amounts for 8.17% of the total area of cropland in 1994. The variation index of land use degree and the dynamic degree index of land use computed are 1.38 and 57.81%, respectively, which demonstrate that land use in Xuzhou is in a development period and the changes are drastic. The frequency index and importance index of the form in which cropland converted into con- struction land are 29.91% and 68.93% respectively. The results indicate that the change is not only widespread in space but a major form of spatial change of land use in the area.

关键词： remote sensing image land use spatio-temporal change Xuzhou city

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Damage characteristics and new constitutive model of sandstone under wet–dry cycles

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Journal of Mountain Science 2022年第7期19卷 2111-2125页

作者： huANG Zhen ZHANG Wei ZHANG Hai ZHANG Jia-bing hu zhao-jian School of Civil Engineering and Architecture Guangxi UniversityNanning530004China Key Laboratory of Engineering Disaster Prevention and Structural Safety Guangxi UniversityNanning530004China

The mechanical properties of rock deteriorate under repeated wet-dry(WD)cycles,causing the deformation and failure of the rock mass.A reasonable damage constitutive model can truly reflect the whole process of rock deformation and ***,it is of great significance to study the damage characteristics and constitutive behaviour of rock subjected to numerous WD ***,sandstone from Tingliang tunnel was sampled for the WD cycle experiment,and uniaxial and triaxial tests were carried out on the rock samples after various numbers of WD cycles to analyze their macroscale damage ***,the damage mechanisms of the rock samples under the action of WD cycling were identified by X-ray diffraction(XRD)and scanning electron microscopy(SEM).Finally,based on the test data,the WD cycle-induced damage variable,Weibull distribution function,damage threshold,Drucker-Prager(D-P)yield criterion and residual strength correction coefficient were introduced,a wet-dry loading(WDL)constitutive damage model that considers the cracking stress of rock masses was established,and the expressions of the corresponding parameters were *** results show that an increasing number of WD cycles induces considerable variations in the macroscopic physical and mechanical parameters(such as the rock sample mass,saturated water content,longitudinal-wave velocity,compressive strength and elastic modulus),and the rate of change presents two stages,the inflection point of their rate of change is the 15th WD ***,the rock sample structure changes from intact and dense to fragmented and unconsolidated;additionally,the surface roughness increases,and the mineral composition *** established constitutive damage model exhibited good agreement with the experimental data;thus,this model can reflect the deformation and failure of rocks under WDL conditions,and the physical meaning of each parameter is clear.

关键词： Wet-dry cycle Sandstone Rock damage Constitutive model

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