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Precursory SST anomalies associated with the convection over the western Pacific warm pool

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chinese Science Bulletin 2002年第8期47卷 696-699页

作者： LU RiyuInstitute of Atmospheric Physics, chinese Academy of Sciences, Beijing 100080, China (e-mail: lr@***) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The convection over the tropical western Pacific warm pool influences significantly the atmospheric circulation and climate in east Asia. Thus, the precursory signals of the convection may be used in the forecast of summer climate in China. According to the present results, the June-July-August (JJA) mean convection intensity over the warm pool is significantly related to the precursory positive and negative sea surface temperatures (SSTs) in the warm pool and in the equatorial central and eastern Pacific, respectively. It is also related to the simultaneous negative surface temperatures west to the Philippines. The analysis on the SSTs associated with the convection over the warm pool in individual month of summer shows that for the convection in June and July, there are precursory SST signals in the warm pool and the equatorial central and eastern Pacific. Therefore, this study shows that only the convection in June and July, rather than that in August, has precursory SST signals, despite the

关键词： warm pool convection precursory SSTs el Nino.

Positive effect of carbohydrate-metabolizing bacteria determines increasing soil organic carbon during long-term fertilization and straw returning in the black soil region of China

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Pedosphere 2024年第5期34卷 853-864页

作者： Yingxin LI Yu SUN eiko e.KURAMAe Shaoqing ZHANG enze WANG Zongmu YAO Fahad NASIR Lei TIAN Qiang GAO Chunjie TIAN State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and Agroecology Chinese Academy of Sciences University of chinese Academy of Sciences Department of Microbial ecology Netherlands Institute of Ecology (NIOO-KNAW) ecology and Biodiversity Group Department of Biology Institute of Environmental Biology Utrecht University Padualaan 8 Jilin Agricultural University Key Lab Soil Resource Sustainable Utilization for Jilin Province Commodity Grain Bases

In the context of global efforts to reduce carbon (C) emissions, several studies have examined the effects of agricultural practices such as straw returning and fertilization on C sequestration by microorganisms. However, our understanding of the specific microbial groups and their roles in long-term C increase remains limited. In this study, a 36-year (1984–2020) farmland experiment was conducted to investigate the impact of bacterial C metabolism on the augmentation of organic C in a Typic Hapludoll (Mollisol) in the black soil region of Jilin Province, Northeast China. Our results demonstrated a noteworthy increase in the diversity of microorganisms in the farmland as a result of long-term straw returning and application of mixed chemical fertilizers. However,by examining the functions of microorganisms involved in C metabolism, it was observed that the effects of fertilization on C metabolism were relatively consistent. This consistency was attributed to a deterministic competitive exclusion process, which minimized the differences between treatment groups. On the other hand, the influence of straw addition on C metabolism appeared to follow a more random pattern. These changes in microbial activity were closely linked to the downregulation of core metabolic pathways related to C metabolism. Notably, long-term fertilization had a negative impact on soil organic C levels, while long-term straw returning plus fertilization resulted in a positive increase in soil organic C. These findings have important implications for enhancing soil organic C and grain yield in the regions with typical black soil.

关键词： community assembly metabolic pathway microbial activity Mollisol soil organic C straw addition

The boundary of palaearctic and oriental realms in western China

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Progress in Natural Science:Materials International 2008年第7期18卷 833-841页

作者： Ling Chen a,b,c, Yanling Songd,*, Shufang Xu e a Northwest Institute of Plateau Biology, chinese Academy of Sciences, Xining 810001, China b Graduate University of the chinese Academy of Sciences, Beijing 100039, China c National Science Foundation of China, Beijing 100085, China d Institute of Zoology, chinese Academy of Sciences, Beijing 100101, China e Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China Graduate University of the chinese Academy of Sciences Beijing 100039 China National Science Foundation of China Beijing 100085 China Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China

In the world-wide zoogeographic division, there has been no consentaneous understanding about the delimitation between palaearctic and oriental realms in western China. In this study, we will discuss the division based on amphibian distribution in Shaanxi, Gansu, Sichuan, Yunnan, and Tibet according to species coefficient similarity between each zoogeographic province. The results show that the northern border lies from Qinling Mountains–Feng Xian (Shaanxi)–Debu (Gansu)–Aba (Sichuan)–Batang–Bomi (Tibet), to Linzhi districts, and the southern border is from Taibai–Feng Xian in Shaanxi–Wen Xian (Gansu)–Songpan–Kangding–Daocheng (Sichuan), to Zhongdian–Gongshan in Yunnan, and westward to Motuo and Bomi district in Tibet.

关键词： Amphibian Zoogeography Palaearctic Oriental Hengduan Mt.

No Incidence of Liver Cancer Was Observed in A Retrospective studyof Patients with Aristolochic Acid Nephropathy

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chinese Journal of Integrative Medicine 2024年第2期30卷 99-106页

作者： SU Tao FANG Zhi-e GUO Yu-ming WANG Chun-yu WANG Jia-bo JI Dong BAI Zhao-fang YANG Li XiAO Xiao-he Renal Division Department of MedicinePeking University First HospitalBeijing(100034)China Department of Pharmacy Chongqing Hospital of Traditional Chinese MedicineChongqing(400021)China Department of Hepatology Fifth Medical Center of Chinese PLA General HospitalBeijing(100039)China China Military Institute of chinese Materia Fifth Medical Center of Chinese PLA General HospitalBeijing(100039)China Phase I Clinical Trials Unit Department of Medicine for Infectious DiseasesFifth Medical Center of Chinese PLA General HospitalBeijing(100039)China Department of Pharmacy Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan(250000)China National Key Laboratory of Kidney Diseases Beijing(100039)China

Objective:To assess the risk of aristolochic acid(AA)-associated cancer in patients with AA nephropathy(AAN).Methods:A retrospective study was conducted on patients diagnosed with AAN at Peking University First Hospital from January 1997 to December ***-term surveillance and follow-up data were analyzed to investigate the influence of different factors on the prevalence of *** primary endpoint was the incidence of liver cancer,and the secondary endpoint was the incidence of urinary cancer during 1 year after taking AA-containing medication to ***:A total of 337 patients diagnosed with AAN were included in this *** the initiation of taking AA to the termination of follow-up,39 patients were diagnosed with *** cases of liver cancer were observed throughout the entire follow-up period,with urinary cancer being the predominant type(34/39,87.17%).Logistic regression analysis showed that age,follow-up period,and diabetes were potential risk factors,however,the dosage of the drug was not significantly associated with urinary ***:No cases of liver cancer were observed at the end of ***,a high prevalence of urinary cancer was observed in AAN *** a direct causality between AA and HCC is challenging.

关键词： aristolochic acid hepatocellular carcinoma urinary cancer drug safety retrospective study

Modified conceptual model for predicting the tendency of alluvial channel adjustment induced by human activities

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chinese Science Bulletin 2001年第S1期46卷 51-57页

作者： XU JiongxinInstitute of Geographical Sciences and Natural Resources Research, chinese Academy of Sciences, Beijing 100101, China (e-mail: xujxin?***) Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

After a discussion about some limitations of Schumm’s conceptual model for prediction of river metamorphosis, this study introduces the channel boundary material as an independent variable, and thereby establishes a conceptual model that can be used to predict the direction of channel adjustment induced by human activities. This model has been tested by data from natural rivers and a laboratory model river, and can be used to explain the complex behavior of channel adjustment after reservoir construction.

关键词： human influence on channels channel boundary condi- tions feedback in channel system prediction of channel adjustment.

Genetic fingerprinting of plankton community provides new insights into aquatic ecology

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Progress in Natural Science:Materials International 2006年第9期16卷 893-898页

作者： YAN Qingyun, YU Yuhe and FeNG Weisong ( Institute of Hydrobiology, chinese Academy of Sciences, Wuhan 430072, China Graduate School of the chinese Academy of Sci-ences, Beijing 100039, China) Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate School of the chinese Academy of Sciences Beijing 100039 China

Over the past two decades, molecular techniques have been widely used in ecological study and molecular ecology has been one of the most important branches of ecology. Meanwhile, genetic fingerprinting analyses have significantly enhanced our knowledge of the diversity and evolutionary relations of the planktonic organisms. Compared with conventional approaches in ecological study (e.g. morphological classification), genetic fingerprinting techniques are simpler and much more effective. This review provides an overview of the principles, advantages and limitations of the commonly used DNA fingerprinting techniques in plankton research. The aim of this overview is to assess where we have been, where we are now and what the future holds for solving aquatic ecological problems with molecular-level information.

关键词： genetic fingerprinting plankton community aquatic ecology genetic diversity.

employment and Development: China's employment Problem and employment Strategy

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World economy & China 1999年第3期7卷 34-48页

作者： Hu Angang Ph.D.(Senior Fellow, National Conditions Analysis and study Group, chinese Academy of Social Sciences e-mail: anganghu@***)

exchange Reaction Between Selenite and Hydroxyl Ion of Variable Charge Soil Surfaces: I. electrolyte Species and pH effects

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Pedosphere 2003年第4期13卷 227-232页

作者： ZHOU SHIWeI, ZHANG GANGYA and ZHANG XIAONIANInstitute of Soil Science, the chinese Academy of Sciences, Nanjing 210008 (China) Institute of Soil Science the Chinese Academy of Sciences Nanjing 210008

Hydroxyl release of red soil and latosol surfaces was quantitatively measuredusing a self-made constant pH automated titration instrument, to study the changes of hydroxylrelease with different added selenite amounts and pH levels, and to study the effects ofelectrolytes on hydroxyl release. Hydroxyl release increased with the selenite concentration, with arapid increase at a low selenite concentration while slowing down at a high concentration. The pHwhere maximum of hydroxyl release appeared was not constant, shifting to a lower valus withincreasing selenite concentration. Hydroxyl release decreased with increasing electrolyteconcentration, and the decrease was very rapid at a low electrolyte concentration but slow at a highelectrolyte concentration. For NaClO_4, NaCl and Na_2SO_4, hydroxyl release was in the order ofNaClO_4 > NaCl >> Na_2SO_4, and the difference was very significant. But for NaCl, KCl and CaCl_2,the order of hydroxyl release was NaCl > KCl > CaCl_2, and the difference was smaller. The amount ofhydroxyl release from Xuwen latosol was greater than that from Jinxian red soil. Hydroxyl releaseexisted in a wider range of pH with Xuwen latosol than with Jinxian red soil, due to theirdifference in soil properties. However, both soils had similar curves of hydroxyl release,indicating the common characteristics of variable charge soils.

关键词： hydroxyl release ion exchange reaction selenite adsorption variable chargesoils

消费者对偏远地区特色农产品的购买行为及其影响因素研究——基于2027个消费者样本数据的考察

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中国农业资源与区划 2024年第3期45卷 117-126页

作者：景娥北京师范大学国际与比较教育研究院北方民族大学商学院

[目的]准确把握偏远地区特色农产品市场的需求特点和消费规律，对于偏远农村地区持续巩固脱贫攻坚成果、进一步实现乡村振兴意义深远。[方法]文章基于2 027位消费者问卷调查数据，建立二元Logistic模型分析偏远地区特色农产品消费的影... 详细信息

[目的]准确把握偏远地区特色农产品市场的需求特点和消费规律，对于偏远农村地区持续巩固脱贫攻坚成果、进一步实现乡村振兴意义深远。[方法]文章基于2 027位消费者问卷调查数据，建立二元Logistic模型分析偏远地区特色农产品消费的影响因素。[结果]（1）家庭成员结构、职业、收入水平对偏远地区特色农产品购买行为具有显著影响；（2）购买动机、购买渠道、获取农产品供给信息的途径对偏远地区特色农产品购买行为具有显著影响；（3）农贸市场变量与溢价支付意愿呈正向显著关系，线下仍然是消费者选购农产品的主要渠道；（4）种植与营销供给质量对消费者农产品购买行为具有显著影响。[结论]该文提出了偏远地区加大绿色和有机特色农产品种植，优化传统农产品市场批发流通网络，不断提升偏远地区特色农产品知名度和美誉度等政策建议。

关键词：偏远地区特色农产品消费行为供给质量回归模型

来源：博看期刊