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A GRADIENT ANALYSIS & MODELING OF THE NECT FOR GLOBAL CHANGE STUDY 被引量:6
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作者 Zhang Xinshi et al.(Laboratory of Quantitative Vegetation Ecology, Institute of Botany, CAS) 《Bulletin of the Chinese Academy of Sciences》 1998年第1期15-21,共7页
The North East China Transect (NECT) is an exemplary region of landmass running along the line of 43°30′ North Latitude and caught between 112° and 130°30′ East Longtitude, and is being sampled by the... The North East China Transect (NECT) is an exemplary region of landmass running along the line of 43°30′ North Latitude and caught between 112° and 130°30′ East Longtitude, and is being sampled by the International Geosphere-Biosphere Program (IGBP) for today’s study on global change. So far, it has already been listed in the first set of IGBP-sponsored transects, becoming a key theatre and "hot spot" for probing terrestrial ecosystems. In terms of biota, the nearly 1,600-kilometre-long tract is located in a mid-latitude zone, featuring a vegetational transition from a temperate timberland of evergreen coniferous forests and broadleaved deciduous forests to a mild-temperate steppe. According to the norms of biome types, it consists of three subzones: meadow steppe, typical steppe and desert steppe in a continuous east-to-west spatial sequence. There are four ecological stations supported by a great number of permanent samples, long-term plots and an enormous build-up of experimental data along 展开更多
关键词 NECT A GRADIENT ANALYSIS MODELING OF THE NECT FOR GLOBAL change study GCTE
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An integrated approach to scaling issues in environmental change study
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作者 LIU Hong-hui, YANG Xiao-huan, WANG Nai-bin, LIU Hai-yan (Center for Resources and Environmental Data, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2000年第4期45-52,共8页
Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecos... Global change research and sustainable development need to be addressed at larger scales in the light of small scale process studies. Much remains to be done before the small scale, process level understanding of ecosystem responses to global change can be reliably translated to larger scales. The paper reviews the status of scaling issues and tries to find how to extrapolate our observations and our findings at site scale up to regional scale and provide ecological information and interpretations at the regional scale. An integrated approach to scaling-up from site to region is proposed combining hierarchical theory, landscape ecology, remote sensing, geographical information system (GIS) with process/mechanistic modeling. Remote sensing and GIS will play key roles in spatial analysis, integration as well as cross scale modeling. 展开更多
关键词 scale issue global change study scaling up integrated approach
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A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats 被引量:1
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作者 Tiao Lin Wei Tong +11 位作者 Abhishek Chandra Shao-Yun Hsu Haoruo Jia Ji Zhu Wei-Ju Tseng Michael A Levine Yejia Zhang Shi-Gui Yan X Sherry Liu Dongming Sun Wise Young Ling Qin 《Bone Research》 SCIE CAS CSCD 2015年第3期164-172,共9页
Spinal cord injury(SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment.Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To ... Spinal cord injury(SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment.Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae,and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography(m CT), micro-finite element, histology, and serum biochemical analyses.At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI. 展开更多
关键词 SCI BONE A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats
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Some Preliminary Results on Pilot Study of Global Change in China 被引量:1
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作者 陈泮勤 严中伟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期201-210,共10页
On the basis of existing data and research results the changes of life supporting environment in China in the history are briefly described. The differences between regional climate variations and climate jump are the... On the basis of existing data and research results the changes of life supporting environment in China in the history are briefly described. The differences between regional climate variations and climate jump are the very important features and phenomena in estimating the trend of environmental evolution in the future. Finally, it is pointed out that sensitive zone is an ideal place to study global change. Many evidences show that the response of environmental elements in the sensitive zones to global change events is very obvious, so that much attention should be paid to the study of sensitive zone. 展开更多
关键词 Some Preliminary Results on Pilot study of Global change in China
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A Sensitivity Study of IAP AGCM to Radiation Changes: Climate Simulation of 125kyr and 115kyr before Present 被引量:1
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作者 王会军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期227-232,共6页
The IAP AGCM was used to simulate the climate of 125kyr and 115kyr before present. We analysed the results and then studied the sensitivity of the model to the changes of radiation distribution induced by orbital para... The IAP AGCM was used to simulate the climate of 125kyr and 115kyr before present. We analysed the results and then studied the sensitivity of the model to the changes of radiation distribution induced by orbital parameter changes. The reasonability of the results was also discussed. 展开更多
关键词 A Sensitivity study of IAP AGCM to Radiation changes Climate Simulation of 125kyr and 115kyr before Present IAP
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Numerical Study for Characteristic Change of Asian Summer Monsoon Circulation and Its Influence Mechanism during the EI Nino Period
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作者 倪允琪 林元弼 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期320-330,共11页
In this paper, the relation between Asian summer monsoon circulation and sea surface temperature anomalies over equatorial central-eastern Pacific is investigated by using a global spectral model. This model has nine ... In this paper, the relation between Asian summer monsoon circulation and sea surface temperature anomalies over equatorial central-eastern Pacific is investigated by using a global spectral model. This model has nine layers in the vertical and the model variables are represented in the horizontal as truncated expansions of the surface spherical harmonics with rhomboidal truncation at wave number 15. The model involves comparatively complete physical processes and parameterizations with mountains.Using the above model, two experimental schemes are designed, namely control case and anomalous sea surface temperature case. The above two schemes are respectively integrated for forty days and the simulated results are obtained from the last 30-day averaged simulations.The simulations show that positive SST anomalies over equatorial central-eastern Pacific weakens Indian monsoon circulation,decreases precipitation in Indian sub-continent whereas it intensifies East Asian monsoon circulation and increases precipitation in East Asian area. All these results reflect the characteristics of Asian summer monsoon during the El Nino period. In this paper, SST anomalies over equatorial central-eastern Pacific have a direct influence on the intensity and position of subtropical high via the wave train over Northern Hemisphere, which is similar to that suggested by Nitta(1987) and the wave train over Southern Hemisphere has an influence on the intensity of Muscarene high and Australia high resulting in affecting cross equatorial flow. As a result, atmospheric interior heat sources and sinks are redistributed because of the change of cross equatorial flow. And the response of atmosphere to the new heat source and sink has a significant influence on Asian summer monsoon. 展开更多
关键词 Asia Numerical study for Characteristic change of Asian Summer Monsoon Circulation and Its Influence Mechanism during the EI Nino Period SSTA Nino EI
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Electrochemical Study on the Change in Valency of Niobium Oxide in the MnO-SiO_2-Nb_2O_5 System
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作者 Tan Zanlin Wei Shoukun University of Science and Technology Beijing 《Rare Metals》 SCIE EI CAS CSCD 1990年第1期1-4,共4页
Change in valency of Nb-oxide in MnO-SiO_2-Nb_2O_5 system was studied with the electrochemical method using ZrO_2 as the solid electrolyte.Thermodynamic analysis has shown that the only possible reaction that could ta... Change in valency of Nb-oxide in MnO-SiO_2-Nb_2O_5 system was studied with the electrochemical method using ZrO_2 as the solid electrolyte.Thermodynamic analysis has shown that the only possible reaction that could take place at the working elec- trode is:2(Nb_2O_5)=2(Nb_2O_4)+O_2 with the a_0 values experimentally evaluated,values of a Nb_2O:/a Nb_2O:were calculated and isoactivity-ratio curves drawn in MnO-SiO_2-Nb_2O_5 triangles at 1418 and 1585K.The simultaneous existence of tetra-and penta-valent Nb mineral constituents in industrial Nb-bearing slags was thus verified experimentally. 展开更多
关键词 Electrochemical study on the change in Valency of Niobium Oxide in the MnO-SiO2-Nb2O5 System SIO MNO
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Study of changes and relationships of cytokines in esophageal cancer patients exposed to perioperative allogeneic transfusion
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《中国输血杂志》 CAS CSCD 2001年第S1期335-,共1页
关键词 study of changes and relationships of cytokines in esophageal cancer patients exposed to perioperative allogeneic transfusion
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Oderly accumulation theory of shale system petroleum resource and its prospecting significance-A case study of Chang 7 Member of Yanchang Formation in Ordos Basin 被引量:5
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作者 Cui Jingwei Zhu Rukai +1 位作者 Li Shixiang Zhang Zhongyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期265-266,共2页
1 Introduction Shale formations bear abundant mineral resource and*unconventional petroleum resource,and the unconventional petroleum resource that contain in the shale formation should be integrated and researched.
关键词 In Oderly accumulation theory of shale system petroleum resource and its prospecting significance-A case study of Chang 7 Member of Yanchang Formation in Ordos Basin
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Studies on Structural Changes of Collagen in Silicosis
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作者 LIYU-RUI HUXUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1994年第4期302-306,共5页
In order to provide scientific information on the prevention and treatment of silicosis,studies about changes of silicotic collagen in lungs were carried out. In this paper, we present experiments about the structural... In order to provide scientific information on the prevention and treatment of silicosis,studies about changes of silicotic collagen in lungs were carried out. In this paper, we present experiments about the structural changes of collagen in silicotic lungs of rats and patients. These included electron microscopy, circular dichroism and infrared spectroscopy studies of collagen fibers. The results indicated that fibers of silicotic collagen were shorter in length, smaller in diameter and decreased in α-helix content. The -Si-O-R- group and -OH group were found increased and -C-C- backbone shortened. The increase of -Si-O-R-group indicated that silica formed linking bridges between collagens which may be the cause of progressive enlargement of nodules 展开更多
关键词 SI In Studies on Structural changes of Collagen in Silicosis
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The digital anatomic study of the changing regularity of thoracic pedicle screw channels in different transverse screw angle
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作者 李严兵 《外科研究与新技术》 2011年第2期93-94,共2页
Objective To investigate the changing regularity of thoracic pedicle screw channel (PSC) in different transverse screw angle(TSA).Methods CT scan images of thoracic vertebrae of a healthy adult ware digitally analyzed... Objective To investigate the changing regularity of thoracic pedicle screw channel (PSC) in different transverse screw angle(TSA).Methods CT scan images of thoracic vertebrae of a healthy adult ware digitally analyzed by Mimics 10.01 展开更多
关键词 length The digital anatomic study of the changing regularity of thoracic pedicle screw channels in different transverse screw angle
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Quantitative Histological Study on Changes of the Cortical Bones after Internal Fixation with Plates of Different Rigidity 被引量:2
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作者 Wang You et al. Dept Orth, Ninth People’s Hospital, Shanghai Second Med Uni, Shanghai 200011. Chin J Orth 《Chinese Medical Journal》 SCIE CAS CSCD 1995年第11期30-30,共1页
In an effect to explore the potemtial role of bone microcirculation causing plate-induced reginal osteoporosis
关键词 Quantitative Histological study on changes of the Cortical Bones after Internal Fixation with Plates of Different Rigidity
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CARDIAC FUNCTION AND HISTOLOGICAL CHANGES AFTER NON-DYNAMIC CARDIOMYOPLASTY AND PRELIMINARY STUDY OF DYNAMIC CARDIOMYOPLASTY
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作者 马勇光 王大玫 +1 位作者 李健宁 朱洪荫 《Chinese Medical Journal》 SCIE CAS CSCD 1994年第11期38-41,共4页
By means of histological method and ultrasound cardiographic (UCG) examination, the left-right ratio of transectional area of muscle fiber of latissimus dorsi muscle (LDM) after non-dynamic cardiomyoplasty was 77.4% ?... By means of histological method and ultrasound cardiographic (UCG) examination, the left-right ratio of transectional area of muscle fiber of latissimus dorsi muscle (LDM) after non-dynamic cardiomyoplasty was 77.4% ?11.7% in GroupⅠ (3 weeks after operation), and 78.4+ 11.6% in Group Ⅱ (3 months after operation). There were muscular atrophy and hyperplasia of LDM, but the basical structure was retained. The ejection fraction (EF) decreased significantly after operation (P<0.05), but the difference between two groups was non?significant. Also, dynamic cardiomyoplasty was performed on a sheep. UCG showed the increased cardiac systolic function after operation. ATPase, succinodehydrogenase (SDH) and PAS examination implied the strengthening of fatigue-esistant ability in skeletal muscles after long-term electrical stimulation. So cardiomyoplasty is suggested to be a supplementary measure in treating end-stage heart failure. 展开更多
关键词 CARDIAC FUNCTION AND HISTOLOGICAL changeS AFTER NON-DYNAMIC CARDIOMYOPLASTY AND PRELIMINARY study OF DYNAMIC CARDIOMYOPLASTY LDM
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Study on the changes in pulmonary artery pressure in elderly Chronic kindney disease patients without end-stage renal disease
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作者 刘昕 《China Medical Abstracts(Internal Medicine)》 2017年第1期50-,共1页
Objective To prospectively investigate the characteristics and correlative influential factors for the changes in pulmonary artery hypertension(PAH)in chronic kidney disease(CKD)patients without end-stage renal diseas... Objective To prospectively investigate the characteristics and correlative influential factors for the changes in pulmonary artery hypertension(PAH)in chronic kidney disease(CKD)patients without end-stage renal disease.Methods Complete clinical and laboratory data of133 outpatients without ESRD(CKD stage 2,3 and 4) 展开更多
关键词 CKD study on the changes in pulmonary artery pressure in elderly Chronic kindney disease patients without end-stage renal disease
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