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补播苜蓿对退化草地植物群落结构和生产力的影响途径

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草地学报 2024年第1期32卷 46-53页

作者：郭美琪郭童天徐民乐张英俊中国农业大学草业科学与技术学院北京100193 农业农村部草地管理与合理利用重点实验室北京100193

近年来,紫花苜蓿(Medicago sativa L.)和黄花苜蓿(Medicago falcata L.)被广泛选作补播材料,用于修复退化草地。尽管研究表明二者的植物学特征存在差异,但鲜有人关注它们是否会通过不同的方式影响退化草地的生产力。为了探究二者对退化... 详细信息

近年来,紫花苜蓿(Medicago sativa L.)和黄花苜蓿(Medicago falcata L.)被广泛选作补播材料,用于修复退化草地。尽管研究表明二者的植物学特征存在差异,但鲜有人关注它们是否会通过不同的方式影响退化草地的生产力。为了探究二者对退化草地的修复效果是否存在差异,并确定影响补播地生产力的限制因素,本研究选取黄花苜蓿和紫花苜蓿作为补播种对退化草甸草原进行了补播,并在隔年对草地植被、土壤理化性质和微生物量进行监测。结果表明,两种苜蓿都可以显著增加退化草地生产力并改善土壤健康状况。然而,紫花苜蓿通过增加土壤铵态氮改变植被群落结构,其补播样地生产力也由土壤速效养分影响;黄花苜蓿通过增加土壤速效磷含量改变植被群落结构,其补播样地生产力由植被群落结构和土壤微生物量共同影响。初步结果表明,黄花苜蓿更适宜在养分贫瘠的退化草地进行补播。此外在选择紫花苜蓿补播时,可以适当施肥以提高补播成功率。

关键词：补播黄花苜蓿紫花苜蓿植物群落结构生产力

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-Quan Yan Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen tian Jiang-Lin Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as supernovae.Lunar samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)Fe.In this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy degrader.For particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the spectrograph.Finally,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS system.These results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)Ni.The sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

Positron Emission Tomography Molecular Imaging for Phenotyping and Management of Lymphoma

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Phenomics 2022年第2期2卷 102-118页

作者： Xiaohui Zhang Han Jiang Shuang Wu Jing Wang Rui Zhou Xuexin He Shufang Qian Shuilin Zhao Hong Zhang Ali Cahid Civelek mei tian Department of Nuclear Medicine and PET Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009ZhejiangChina Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou 310009ZhejiangChina Institute of Nuclear Medicine and Molecular Imaging of Zhejiang University Hangzhou 310009ZhejiangChina PET-CT Center Fujian Medical University Union HospitalFuzhou 350001FujianChina Department of Medical Oncology The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009ZhejiangChina Key Laboratory for Biomedical Engineering of Ministry of Education Zhejiang UniversityHangzhou 310027ZhejiangChina College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou 310027ZhejiangChina Department of Radiology and Radiological Science Johns Hopkins MedicineBaltimoreMD 21287USA Human Phenome Institute Fudan UniversityShanghai 201203China

Positron emission tomography(PET)represents molecular imaging for non-invasive phenotyping of physiological and biochemical processes in various oncological diseases.PET imaging with 18F-fluorodeoxyglucose(18F-FDG)for glucose metabolism evaluation is the standard imaging modality for the clinical management of lymphoma.One of the 18F-FDG PET applications is the detection and pre-treatment staging of lymphoma,which is highly sensitive.18F-FDG PET is also applied during treatment to evaluate the individual chemo-sensitivity and accordingly guide the response-adapted therapy.At the end of the therapy regiment,a negative PET scan is indicative of a good prognosis in patients with advanced Hodgkin’s lymphoma and diffuse large B-cell lymphoma.Thus,adjuvant radiotherapy may be alleviated.Future PET studies using non-18F-FDG radiotracers,such as 68Ga-labeled pentixafor(a cyclic pentapeptide that enables sensitive and high-contrast imaging of C-X-C motif chemokine receptor 4),68Ga-labeled fibroblast activation protein inhibitor(FAPI)that reflects the tumor microenvironment,and 89Zr-labeled atezolizumab that targets the programmed cell death-ligand 1(PD-L1),may complement 18F-FDG and offer essential tools to decode lymphoma phenotypes further and identify the mechanisms of lymphoma therapy.

关键词： Positron emission tomography(PET) Lymphoma Glucose metabolism Staging Response assessment

适用于智能健康监测平台构建的Revit-ANSYS协同分析

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公路 2024年第1期69卷 358-363页

作者：徐梅刘晨光田石柱苏州科技大学土木工程学院苏州市215011 中交二航局建筑工程有限公司武汉市430056

打造BIM数字模型与结构健康监测技术相结合的智能健康监测平台,可更好地利用结构健康监测数据,实时掌握结构的工作状态。但BIM模型不能直接在结构层面进行有限元计算分析,限制了智能健康监测平台应用的广度与深度。为将BIM数字模型与有... 详细信息

打造BIM数字模型与结构健康监测技术相结合的智能健康监测平台,可更好地利用结构健康监测数据,实时掌握结构的工作状态。但BIM模型不能直接在结构层面进行有限元计算分析,限制了智能健康监测平台应用的广度与深度。为将BIM数字模型与有限元分析模型进行交互融合,提出一种基于Revit与ANSYS软件的协同建模分析方法:首先建立结构BIM数字模型,并利用Revit API技术,实现Revit端BIM模型信息向ANSYS的有效传递,而后在ANSYS端将所获取BIM模型信息利用APDL语言二次处理,完成有限元模型的建立并进行结构数值模拟计算。基于此方法,以某三跨连续梁桥为例,对该协同分析方法的有效性与准确性进行了验证。

关键词：桥梁工程结构健康监测协同分析 BIM模型数值模拟计算

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新疆农业全要素生产率的空间分异及动态演进

数学的实践与认识 2024年第4期54卷 1-17页

作者：侯震梅周天宇周勇新疆财经大学统计与数据科学学院新疆乌鲁木齐830012

利用新疆84个县域2009-2018年农业投入与产出数据,基于HicksMoorsteen指数测算农业全要素生产率的增长水平,通过Dagum基尼系数分解法与扩展的分布动态学模型,揭示新疆农业全要素生产率增长的区域差异及分布动态演进规律.研究发现:新疆... 详细信息

利用新疆84个县域2009-2018年农业投入与产出数据,基于HicksMoorsteen指数测算农业全要素生产率的增长水平,通过Dagum基尼系数分解法与扩展的分布动态学模型,揭示新疆农业全要素生产率增长的区域差异及分布动态演进规律.研究发现:新疆农业全要素生产率指数整体偏低,空间分异程度呈现先扩大后缩小的趋势,超变密度是农业全要素生产率增长分异的主要来源,农业全要素生产率增长具有β收敛特征.

关键词：农业全要素生产率区域差异分布动态基尼系数

Mitochondrial genome of Chthamalus challengeri(Crustacea:Sessilia): gene order comparison within Chthamalidae and phylogenetic consideration within Balanomorpha

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Acta Oceanologica Sinica 2019年第6期38卷 25-31页

作者： Panpan Chen Jun Song Xin Shen Yuefeng Cai Ka Hou Chu Yongqi Li mei tian Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology Huaihai Institute of TechnologyLianyungang 222005China Co-Innovation Center of Jiangsu Marine Bio-industry Technology Lianyungang 222000China Simon F. S. Li Marine Science Laboratory School of Life SciencesThe Chinese University of Hong KongShatinN.T.Hong KongChina

Acorn barnacles are important model species in researches on intertidal ecology, larval development and biofouling. At present, with the development of mitochondrial genomics, it is helpful to understand the phylogenetic relationship from the mitogenomic level. The complete mitochondrial genome of Chthamalus challengeri was presented. The genome is a circular molecule of 15 358 bp. Compared with other species in Balanomorpha, the non-coding region is longer, while the length of the genes is similar to the other species. The overall A+T content of the mitochondrial genome of C. challengeri is 70.5%. There are variations of initiation and stop codons in the known Balanomorpha mitochondrial genomes. The C. challengeri and C. antennatus within the same genus share the identical gene arrangement. However, the gene arrangement of different genera in Chthamalidae is different, as there is a translocation between two tRNA genes and an inversion involving a large gene block. In particular, both srRNA and lrRNA of the two species in Chthamalus are encoded in the heavy strand, differing from the former Balanomorpha species. The topology and gene arrangement in Chthamalidae support each other. Phylogenetic analysis indicates that the Chthamalidae is monophyletic, while the Balanidae and Archaeobalanidae are polyphyletic.

关键词： Balanomorpha Chthamalus challengeri mitochondrial genome gene rearrangement phylogeny

Molecular, Functional, and Structural Imaging of Major Depressive Disorder

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Neuroscience Bulletin 2016年第3期32卷 273-285页

作者： Kai Zhang Yunqi Zhu Yuankai Zhu Shuang Wu Hao Liu Wei Zhang Caiyun Xu Hong Zhang Takuya Hayashi mei tian Department of Nuclear Medicine The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009 China Zhejiang University Medical PET Center Hangzhou 310009China Institute of Nuclear Medicine and Molecular Imaging Zhejiang University Hangzhou 310009 China Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou 310009 China Department of Orthopedics The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009 China Functional Architecture Imaging Unit RIKEN Center for Life Science Technologies Kobe 650-0047 Japan

Major depressive disorder（MDD） is a significant cause of morbidity and mortality worldwide,correlating with genetic susceptibility and environmental risk factors.Molecular,functional,and structural imaging approaches have been increasingly used to detect neurobiological changes,analyze neurochemical correlates,and parse pathophysiological mechanisms underlying MDD.We reviewed recent neuroimaging publications on MDD in terms of molecular,functional,and structural alterations as detected mainly by magnetic resonance imaging（MRI） and positron emission tomography.Altered structure and function of brain regions involved in the cognitive control of affective state have been demonstrated.An abnormal default mode network,as revealed by resting-state functional MRI,is likely associated with aberrant metabolicand serotonergic function revealed by radionuclide imaging.Further multi-modal investigations are essential to clarify the characteristics of the cortical network and serotonergic system associated with behavioral and genetic variations in MDD.

关键词： Major depressive disorder Molecularimaging ositron emission tomography Magneticresonance imaging Functional connectivity Serotonin

黄芪根腐致病尖孢镰刀菌实时荧光定量PCR检测体系的建立及应用

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农业生物技术学报 2024年第3期32卷 720-729页

作者：赵丽梅赵利田洪岭高芬山西大学中医药现代研究中心山西农业大学经济作物研究所山西大学应用化学研究所

尖孢镰刀菌(Fusarium oxysporum)是引起蒙古黄芪(Astragalus membranaceus var. mongholicus,AMM)根腐病的优势致病菌之一。为了快速准确地检测和定量黄芪植株及其种植地土壤中的尖孢镰刀菌，根据延长因子(elongation factor-1α, EF-1... 详细信息

尖孢镰刀菌(Fusarium oxysporum)是引起蒙古黄芪(Astragalus membranaceus var. mongholicus,AMM)根腐病的优势致病菌之一。为了快速准确地检测和定量黄芪植株及其种植地土壤中的尖孢镰刀菌，根据延长因子(elongation factor-1α, EF-1α)序列设计引物并验证其特异性，进而建立该病菌的实时荧光定量PCR (real-time quantitative PCR, qRT-PCR)检测体系，并运用该体系对黄芪和土壤样本内的尖孢镰刀菌进行检测。结果表明，设计的引物FaeF2/FaeR2特异性良好；所建体系对黄芪中尖孢镰刀菌DNA的检测灵敏度为0.896 pg/μL，土壤中尖孢镰刀菌孢子量的检测限度为102个分生孢子/g；标准曲线的相关系数分别为0.998和0.973；重复性评价显示该方法可靠、稳定。利用qRT-PCR方法对黄芪和土壤样本进行检测，接种发病样本、疑似发病样本和土壤样本中，尖孢镰刀菌的总检出率分别为100%、66.7%和43.75%；尖孢镰刀菌在黄芪中的定殖量与病情指数正相关，且相同种植年限下，发病土壤中尖孢镰刀菌孢子数显著大于健康土壤。综上结果表明，所建方法适用于黄芪及土壤中尖孢镰刀菌的检测。本研究可为黄芪根腐病的快速诊断、准确评价及土壤预警提供技术支持。

关键词：蒙古黄芪根腐病尖孢镰刀菌实时荧光定量PCR (qRT-PCR) 检测体系

基于限制性立方样条模型分析青少年三酰甘油-葡萄糖指数及其衍生指数与血压异常的关系

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中国当代儿科杂志 2024年第1期26卷 54-61页

作者：田梅马晓燕佟玲玲贾磊娜丁文清宁夏医科大学公共卫生学院宁夏银川750004 宁夏环境因素与慢性病控制重点实验室宁夏银川750004

目的探讨青少年三酰甘油-葡萄糖指数(triglyceride-glucose index,简称TyG)、三酰甘油-葡萄糖-体重指数(triglyceride-glucose-body mass index,简称TyG-BMI)以及三酰甘油-葡萄糖-腰围指数(triglycerideglucose-waist circumference index,简称TyG-WC)与血压异常的关系,为青少年高血压的防控提供理论依据。方法通过分层整群抽样的方法抽取银川市1572例12~18岁青少年进行问卷调查、体格测量和实验室检测,通过logistic回归分析模型结合限制性立方样条分析青少年TyG、TyG-BMI、TyG-WC与血压异常的关系。结果多因素logistic回归分析显示,校正混杂因素后,TyG、TyG-BMI、TyG-WC最高四分位数组发生血压异常的风险分别为最低四分位数组的1.48倍(95%CI:1.07~2.04)、3.71倍(95%CI:2.67~5.15)和4.07倍(95%CI:2.89~5.73);且随着TyG、TyG-BMI和TyG-WC水平升高,血压异常风险逐渐增加(P<0.05)。TyG-BMI与血压异常风险之间存在非线性剂量-反应关系(P_(总趋势)<0.001,P_(非线性)=0.002);TyG(P_(总趋势)<0.001,P_(非线性)=0.232)、TyG-WC(P_(总趋势)<0.001,P_(非线性)=0.224)均与血压异常风险之间存在线性剂量-反应关系。结论TyG及其衍生指数水平升高可增加青少年发生血压异常的风险,且与血压异常风险之间存在线性或非线性剂量-反应关系。

关键词：三酰甘油-葡萄糖指数三酰甘油-葡萄糖-体重指数三酰甘油-葡萄糖-腰围指数血压青少年