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STATUS, CAUSES AND COMBATING SUGGESTIONS OF SANDY DESERTIFICATION IN QINGHAI-TIBET PLATEAU

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Chinese Geographical Science 2005年第4期15卷 289-296页

作者： liU Yi-hua DONG Guang-rong li Sen DONG Yu-xiang School of geography Guangzhou University Guangzhou 510405 P. R. China Cold and A rid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 P. R. China department of Tourism and geography Foshan University Foshan 528000 P. R. China department of Territorial Resource and Environment SUN Yat-Sen University Guangzhou 510275 P. R. China

The Qinghai-Tibet Plateau is one of the major sandy desertification regions of china. Based on the recent investigation on sandy desertification, this paper analyses the status such as the type, area, distribution and damage of sandy land desertification in the plateau. Through the analysis on the factors affecting sandy desertification in the region’s natural and socio-economic systems as well as the processes and their interrelations, it can be concluded that sandy desertification in the Qinghai-Tibet Plateau resulted from the combined actions of normal natural sand drift processes, natural sandy desertification processes caused by climatic changes and man-made sandy desertification caused by improper human activities. In addition, it also predicts the possible developmental trend including the increase in desertification area and the enhancement in desertification developmental degree with the exacerbation of the complex processes, and finally puts forward some strategic suggestions to combat sandy desertification in the coming years.

关键词： Qinghai-Tibet Plateau sandy desertification desertification control

正常足月新生儿出生3个月内肠道菌群的定植规律分析

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贵州医科大学学报 2024年第1期49卷 109-114页

作者：张金铃姜华杨萌婷马丽雷光霞杜欣欣冯梅余涵王鉴贵州医科大学临床医学院贵州贵阳550000 贵州医科大学附属医院小儿外科贵州贵阳550004 贵州医科大学附属医院新生儿科贵州贵阳550004

目的探讨正常足月新生儿出生3个月内肠道菌群的定植规律。方法收集20例正常足月新生儿及其孕母的临床资料,取新生儿出生后第1天(C0)、第3天(C1)、第1周(C2)、第1个月(C3)及第3个月(C4)的粪便标本,采用Illumina NovaSeq PE250进行16S... 详细信息

目的探讨正常足月新生儿出生3个月内肠道菌群的定植规律。方法收集20例正常足月新生儿及其孕母的临床资料,取新生儿出生后第1天(C0)、第3天(C1)、第1周(C2)、第1个月(C3)及第3个月(C4)的粪便标本,采用Illumina NovaSeq PE250进行16S核糖体RNA(16S rRNA)V3+V4区测序,采用生物信息学分析肠道菌群的定植规律。结果正常足月新生儿粪便中肠道菌群的扩增子序列变异体(ASV)数目、Shannon指数于C0时最高;正常足月新生儿出生3个月内的肠道菌群以变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Actinobacteriota)、拟杆菌门(Bacteroidota)为优势菌门,Proteobacteria相对丰度随日龄由高变低再逐渐增高,Firmicutes与之相反;正常足月新生儿生3个月内优势菌群在属水平的演变依次为罗尔斯通菌属(Ralstonia)、链球菌属(Streptococcus)、双歧杆菌属(Bifidobacterium),随日龄增加,Bifidobacterium相对丰度逐渐升高,C4时达44.18%且为优势菌属。结论正常足月新生儿生3个月内肠道菌群的多样性、组成结构及相对丰度出现变化。

关键词：婴儿新生足月儿肠道菌群多样性相对丰度 16S核糖体RNA

Feasibility of terahertz imaging for discrimination of human hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2019年第2期11卷 153-160页

作者： feng Duan Yu-Ye Wang De-Gang Xu Jia Shi lin-Yu Chen li Cui Yan-hua Bai Yong Xu Jing Yuan Chao Chang department of Interventional Radiology the General Hospital of Chinese People’s Liberation Army Institute of Laser and Optoelectronics School of Precision Instruments and Optoelectronic Engineering Key Laboratory of Optoelectronic Information Science and Technology (Ministry of Education) Tianjin University department of Hepatobiliary and Pancreatic Surgical Oncology the General Hospital of Chinese People’s liberation Army department of Pathology the General Hospital of Chinese People’s Liberation Army Advanced Interdisciplinary Technology Research Center National Innovation Institute of Defense Technology

BACKGROUND Hepatocellular carcinoma(HCC) is one of the most common malignant tumors worldwide, and novel methods for early/rapid diagnosis of HCC are ***(THz) spectroscopy is considered to have the potential to distinguish between normal liver tissue and HCC tissue; however, there are few reports on *** conduct this observational study to explore the feasibility of THz imaging for the diagnosis of *** To evaluate the feasibility of THz for discriminating between HCC and normal liver tissues using fresh tissue specimens obtained from HCC patients who had undergone *** normal liver tissue and HCC tissue were cryosectioned into 50 μm-thick slicesand placed on cover glass. Two adjacent tissue sections were separated subjected to histopathological examination by hematoxylin and eosin staining or THz transmission examination, and THz images were compared with pathologically mapped images. We determined the typical tumor and normal liver tissue regions by pathological examination; the corresponding areas of adjacent sections were examined by THz *** The transmission rate of HCC tissue was 0.15-0.25, and the transmission rate of typical HCC tissue was about 0.2. THz transmittance in normal liver tissue is slightly higher than 0.4, but there were many influencing factors, including the degree of liver cirrhosis, fat components, ice crystals in frozen sections, and *** In conclusion, this study shows that THz imaging can detect HCC tissue. Further research will yield more detailed data of the THz transmission rates of HCC tissue with different degrees of differentiation.

关键词： Terahertz imaging Hepatocellular carcinoma Hematoxylin and eosin staining Terahertz transmittance liver pathology

海拔梯度和原生林转换对北热带山地土壤有机碳密度的影响

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土壤通报 2024年第2期55卷 391-400页

作者：王平俞筱押丁智强谭小爱华红莲李玉辉云南师范大学地理学部云南昆明650500 黔南民族师范学院旅游与资源环境学院贵州都匀558000 福建师范大学地理科学学院福建福州350007

[目的]探究北热带土壤有机碳密度(SOCD)对海拔梯度和原生林转换的响应特征及内在机制。[方法]以中国红河蝴蝶谷地区海拔105~3012 m的山地和原生热带雨林转换而来的香蕉和橡胶种植园为研究对象,研究0~40cm土壤有机碳(SOC)在海拔梯度和原... 详细信息

[目的]探究北热带土壤有机碳密度(SOCD)对海拔梯度和原生林转换的响应特征及内在机制。[方法]以中国红河蝴蝶谷地区海拔105~3012 m的山地和原生热带雨林转换而来的香蕉和橡胶种植园为研究对象,研究0~40cm土壤有机碳(SOC)在海拔梯度和原生林转换后的变化情况,并用最小角回归(Least Angle Regression,LARS)、偏相关和皮尔森相关分析探究气候和土壤理化因子的耦合驱动作用。[结果](1)海拔与SOC呈显著正相关,从低海拔的砖红壤带到高海拔的棕壤带,SOC储量增加了452.1%(0~40 cm土层),该变化主要受土壤容重(BD)、酸碱度(pH)、全磷(TP)、速效氮(AN)和年平均气温(MAT)的驱动,偏相关分析表明MAT对SOCD的作用不随土壤理化因子而改变,但土壤理化因子对SOCD的作用却受MAT的控制。(2)低地原生林转换为橡胶和香蕉种植园后SOC储量分别损失了49.7%和43.5%,SOCD损失与土壤BD增加和C/N减小有关,二者反映了原生林转换后凋落物归还减少和侵蚀加强两个重要的生态过程。[结论]北热带山地土壤碳密度极易受到年均气温的影响,而低海拔土壤碳密度主要受人类活动干扰的调控,未来对土壤碳密度的评估除考虑垂直梯度分异外,还应考虑原生林转换为种植园导致的土壤有机碳损失。

关键词：土壤有机碳密度海拔梯度热带雨林原生林转换热带种植园

Mass Spectrometry-based Proteomics in Acute Respiratory Distress Syndrome： A Powerful Modality for Pulmonary Precision Medicine

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Chinese Medical Journal 2016年第19期129卷 2357-2364页

作者： Xue-feng Xu hua-Ping Dai Yan-Ming li Fei Xiao Chen Wang department of Surgical Intensive Care Medicine Beijing Anzhen Hospital Capital Medical University Beijing 100029 China National Clinical Research Centre for Respiratory Medicine Beijing Hospital Beijing 100730 China department of Respiratory and Critical Care Medicine China-Japan Friendship Hospital Beijing 100029 China

Objective：Acute respiratory distress syndrome （ARDS） is an acute and lethal clinical syndrome that is characterized by hypoxemic respiratory failure and diffuse alveolar inflammatory *** review aimed to search and discuss the mass spectrometry （MS）-based proteomic studies on different subsets of ARDS *** Sources：Original research articles were collected from the PubMed database published in English up to December *** Selection：The literature search was done using the term ＂（acute lung injury OR acute respiratory distress syndrome）AND （proteomics OR proteome OR mass spectrum OR differential in-gel electrophoresis OR two-dimensional polyacrylamide gel electrophoresis）＂.Related original research articles were included and were carefully ***：Eight original proteomic researches on ARDS patients were *** common proteomic modalities were two-dimensional （2D）high-performance liquid chromatography-based electronic spray ion-MS/MS and 2D-polyacrylamide gel electrophoresis/differential in-gel electrophoresis-based matrix-assisted laser desorption ionization-time of flight/*** compared the proteome between ARDS patients and normal controls and analyzed the dynamic changes ofproteome at different ARDS stages or *** disturbed proteome in ARDS patients includes plasma acute-phase proteins,inflammatory/immune-associated proteins,and coagulation ***：Although several previous studies have provided some useful information about the lung proteome in ARDS patients and gained several interesting disease-associated biomarkers,clinical proteomic studies in ARDS patients are still in the initial *** increased cooperation is still needed to establish a global and faithful database containing disease-specific proteome from the largest ARDS subsets.

关键词： Acute Respiratory Distress Syndrome Biomarkers Mass Spectrometry Proteomics

Patterns and driving factors of leaf C,N,and P stoichiometry in two forest types with different stand ages in a mid-subtropical zone

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Forest Ecosystems 2022年第1期9卷 47-56页

作者： Yunni Chang Quanlin Zhong Hong Yang Chaobin Xu Weiping hua Baoyin li Fujian Provincial Key Laboratory for Plant Eco-physiology Fujian Normal UniversityFuzhou350007China College of Geographical Sciences Fujian Normal UniversityFuzhou350007China State Key Laboratory for Subtropical Mountain Ecology of the Ministry of Science and Technology and Fujian Province Fujian Normal UniversityFuzhou350007China College of Environmental Science and Engineering Fujian Normal UniversityFuzhou350007China department of geography and Environmental Science University of ReadingReadingUK College of Ecological and Resources Engineering Wuyi UniversityWuyishan354300China College of Forestry Fujian Agriculture and Forestry UniversityFuzhou350002China

Background:Carbon(C),nitrogen(N),and phosphorus(P)stoichiometry is a key indicator of nutrient utilization in plants,and C/N/P ratios are related to the life histories and adaptation strategies of tree ***,no consensus has been reached on how leaf stoichiometric characteristics are affected by forest type and stand *** relationships between leaf stoichiometry and geographical,meteorological,and soil factors also remain poorly ***:Leaf and soil were sampled from forest stands of different age groups(young,middle-aged,near-mature,and mature)in two forest types(Chinese fir(Cunninghamia lanceolata)forests and evergreen broadleaved forests).The relationships between leaf C,N,and P stoichiometric parameters and geographical,meteorological,and soil factors were analysed by using redundancy analysis(RDA)and stepwise linear regression ***:Leaf C concentrations peaked in the near-mature stands with increasing age irrespective of forest *** N and P concentrations fluctuated with a rising trend in Chinese fir forests,while decreased first and increased later from young to mature phases in natural evergreen broadleaved *** fir forests were primarily limited by N and P,while natural evergreen broadleaved forests were more susceptible to P *** C,N,and P stoichiometric characteristics in Chinese fir forests were mainly affected by the soil total P concentration(SP),longitude(LNG),growing season precipitation(GSP)and mean temperature in July(JUT).The leaf C concentration was mainly affected by GSP and JUT;leaf N and P concentrations were both positively correlated with LNG;and leaf P was positively correlated with *** evergreen broadleaved forests,however,leaf stoichiometric parameters displayed significant correlations with latitude(LAT)and mean annual precipitation(MAP).Conclusions:Leaf stoichiometry differed among forest stands of different age groups and forest *** C,N,and P stoichiometry was pri

关键词： Leaf stoichiometry C/N/P ratios Environmental factors Stand age groups Chinese fir forest Natural evergreen broadleaved forest

The ecological cost of land reclamation and its enlightenment to coast sustainable development in the northwestern Bohai Bay,china

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Acta Oceanologica Sinica 2017年第4期36卷 97-104页

作者： ZHU Gaoru XU Xuegong WANG Hui li Tuoyu feng Zhe Transport Planning and Research Institute Ministry of Transport College of Urban and Environmental Sciences & Laboratory for Earth Surface Process of Ministry of Education Peking University Northeast Institute of geography and Agricultural Ecology Chinese Academy of Sciences The Editorial department of Journal of Capital normal university Capital Normal University School of Land Science and Technology China University of Geoscience

Land has been widely reclaimed in large area in coastal zones all over the world to relieve the pressure of land shortage,promoting social development and economic *** has become a focus of land reclamation with the rapid industrialization and *** the Binhai New Area of Tianjin to the Caofeidian New Area of Tangshan,the undergoing project of land reclamation on the northwest coast of Bohai Bay,china,is the largest in the *** clarify the environmental issues and benefit sustainable development of the coastal zone,we conducted both retrospective and predictive assessments of the ecological cost caused by land reclamation on the northwest coast of Bohai Bay,*** calculated the ecological costs of ten aspects of the four ecosystem services,i.e.,supply,regulation,support and culture,with the monetary estimate *** results indicate that the ecological cost of the new land reclamation is US$971.9 million from 2000 to 2010 and that the cost will be US$702.1 million from 2010 to *** costs of gas regulation and marine food supply account for the greatest parts of the total *** for land reclamation oriented to sustainable development in the study area are put forward,including a rational planning based on the comprehensive evaluation,reducing the amount of land reclamation area,optimizing the structure of the reclaimed land,reclaiming land with the concept of ＂low impact development＂ and implementing ecological compensation mechanisms,etc.

关键词： coastal zone land reclamation ecosystem service cost valuation Bohai Bay china

Scutellaria barbate extract induces apoptosis of hepatoma H22 cells via the mitochondrial pathway involving caspase-3

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World Journal of Gastroenterology 2008年第48期14卷 7321-7328页

作者： Zhi-Jun Dai Xi-Jing Wang Zong-Fang li Zong-Zheng Ji Hong-Tao Ren Wei Tang Xiao-Xu liu hua-feng Kang Hai-Tao Guan ling-Qin Song department of Oncology the Second Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China department of General Surgery the Second Affiliated Hospital Medical School of Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China department of life Science Shaanxi Normal University Xi'an 710061 Shaanxi Province China

AIM： To study the growth inhibitory and apoptotic effects of Scutellaria barbata *** （S. barbata） and to determine the underlying mechanism of its antiturnor activity in mouse liver cancer cell line ***： Proliferation of H22 cells was examined by MTT assay. Cellular morphology of PC-2 cells was observed under fluorescence microscope and transmission electron microscope （EM）. Mitochondrial transmembrane potential was determined under laser scanning confocal microscope （LSCM） with rhodamine 123 staining. Flow cytometry was performed to analyze the cell cycle of H22 cells with propidium iodide staining. Protein level of cytochrome C and caspase-3 was measured by semi-quantitive RT-PCR and Western blot analysis. Activity of caspase-3 enzyme was measured by ***： M-I-I- assay showed that extracts from S. barbata （ESB） could inhibit the proliferation of H22 cells in a time-dependent manner. Among the various phasesof cell cycle, the percentage of cells in S phase was significantly decreased, while the percentage of cells in G1 phase was increased. Flow cytometry assay also showed that ESB had a positive effect on apoptosis. Typical apoptotic morphologies such as condensation and fragmentation of nuclei and blebbing membrane of apoptotic cells could be observed under transmission electron microscope and fluorescence microscope. To further investige the molecular mechanism behind ESB-induced apoptosis, ESB-treated cells rapidly lost their mitochondrial transmembrane potential, released mitochondrial cytochrome C into cytosol, and induced caspase-3 activity in a dose-dependent manner. CONCLUSION： ESB can effectively inhibit the proliferation and induce apoptosis of H22 cells involving loss of mitochondrial transmembrane potential, release of cytochrome C, and activation of caspase-3.

关键词： Scute/laria barbate Hepatoma Apoptosis Mitochondrial transmembrane potential Serum pha-rmacology

Towards the meV limit of the effective neutrino mass in neutrinoless double-beta decays

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Chinese Physics C 2020年第3期44卷 1-11页

作者： Jun Cao Guo-yuan huang Yu-feng li Yifang Wang liang-Jian Wen Zhi-zhong Xing Zhen-hua Zhao Shun Zhou Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China department of Physics Liaoning Normal UniversityDalian 116029China

We emphasize that it is extremely important for future neutrinoless double-beta(0νββ)decay experiments to reach the sensitivity to the effective neutrino mass|mββ|≈1 *** such a sensitivity,it is highly possible to discover the signals of 0νββ *** no signal is observed at this sensitivity level,then either neutrinos are Dirac particles or stringent constraints can be placed on their Majorana *** this paper,assuming the sensitivity of|mββ|≈1 meV for future 0νββ decay experiments and the precisions on neutrion oscillation parameters after the JUNO experiment,we fully explore the constrained regions of the lightest neutrino mass m1 and two Majorana-type CP-violating phases{ρ,σ}.Several important conclusions in the case of normal neutrino mass ordering can be ***,the lightest neutrino mass is severely constrained to a narrow range m1∈[0.7,8]meV,which together with the precision measurements of neutrino mass-squared differences from oscillation experiments completely determines the neutrino mass spectrum m2∈[8.6,11.7]meV ing phases is limited to ρ∈[130°,230°],which cannot be obtained from any other realistic ***,the sum of three neutrino masses is found to beΣ≡m1+m2+m3∈[59.2,72.6]meV,while the effective neutrino mass for beta decays turns out to be mβ≡(|Ue1|2m1^2+|Ue2|2m2^2+|Ue3|2m3^2)1/2∈[8.9,12.6]*** observations clearly set up the roadmap for future non-oscillation neutrino experiments aiming to solve the fundamental problems in neutrino physics.

关键词： neutrinoless double-beta decays absolute neutrino masses Majorana CP phases