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配合饲料、变态素对蟾蜍蝌蚪变态的影响
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作者 熊晓英 《江西水产科技》 1994年第2期31-32,30,共3页
配合饲料、变态素对蟾蜍蝌蚪变态的影响熊晓英(江西省水产科研所)近年来,牛蛙、美国青蛙得到广泛养殖。关于蛙类的繁殖、饲料、病害防治等方面的研究都见过报导,但有关配合饲料,变态素对蝌蚪变态的影响还未见过报导,本试验将用特... 配合饲料、变态素对蟾蜍蝌蚪变态的影响熊晓英(江西省水产科研所)近年来,牛蛙、美国青蛙得到广泛养殖。关于蛙类的繁殖、饲料、病害防治等方面的研究都见过报导,但有关配合饲料,变态素对蝌蚪变态的影响还未见过报导,本试验将用特制的配合饲料,一定浓度的变态素来研... 展开更多
关键词 蛙类 配合饲料 变态素 蟾蜍 蝌蚪
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Dynamic Analysis on Organic Matter and Nitrogen Pollution of Dongchang Lake
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作者 翟胜 王东丽 +5 位作者 肖栋梁 韩婷 江振 齐永强 周建伟 王巨媛 《Agricultural Science & Technology》 CAS 2014年第8期1390-1394,1402,共6页
The aim was to explore dynamic changes of organic matter and nitrogen pol ution in Dongchang Lake. [Method] Monitoring data, including BOD5, CODCr, NH3-N and TN, of Dongchang Lake were chosen for analysis during 2002-... The aim was to explore dynamic changes of organic matter and nitrogen pol ution in Dongchang Lake. [Method] Monitoring data, including BOD5, CODCr, NH3-N and TN, of Dongchang Lake were chosen for analysis during 2002-2011. [Result] Water quality of the six lake districts showed deteriorating in monitor-ing period, and TN was the dominant pol ution factor; BOD5/CODCr ratio was low, suggesting biodegradability of organic pol utant in the lake was lower. NH3/TN ratio was higher, indicating NH3-N was a major factor causing nitrogen exceeding in 2010. In addition, correlations between BOD5 and CODCr and between NH3-N and TN in the lake districts maintained at a significant level. [Conclusion] The research provides references for improving water in Dongchang Lake. 展开更多
关键词 Dongchang Lake Organic pol utant Nitrogen pol ution Dynamic trend Correlation analysis
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Dynamic Changes of Nitrogen in Saline-alkaline Paddy Field and Its Potential Environmental Impacts 被引量:1
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作者 叶洁琼 袁瑞霞 +1 位作者 王兆慧 柳建设 《Agricultural Science & Technology》 CAS 2011年第3期443-446,460,共5页
[Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as stu... [Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as study object,field test method was used to explore the dynamic changes was strong alkof nitrogen in paddy field of the region and its potential impact on environment. [Result] The soil in test regionaline with high CEC and C/N ratios,as well as poor preserving capacity of fertilizer. During the two-year field experiment,the indicators of salinization fluctuated. Initially,the concentrations of total nitrogen and ammonia nitrogen reached their maximum values,then decreased over time as a result of heavy rain. The maximum of nitrate concentration appeared later than those of total nitrogen and ammonia nitrogen. Ammonia volatilization accounted for 18.9%-28.8% of the nitrogen loss. The total nitrogen concentration in surface water was higher than the national Class Ⅲ surface water environmental quality standard. The concentration of ammonia from the recession flow of agricultural field was considerably high,which would potentially threaten the fishery in the downstream of Chagan Lake. [Conclusion] The study provided theoretical basis for saline-alkaline soil management and conservation of water and fishery resources. 展开更多
关键词 Saline-alkaline soil NITROGEN Dynamic changes Potential environmental impact
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Dynamics of Nitrogen Speciation in Horticultural Soils in Suburbs of Shanghai,China 被引量:6
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作者 GE Ti-Da HUANG Dan-Feng +2 位作者 P. ROBERTS D. L. JONES SONG Shi-Wei 《Pedosphere》 SCIE CAS CSCD 2010年第2期261-272,共12页
Dissolved organic nitrogen (DON) represents a significant pool of soluble nitrogen (N) in soil ecosystems. Soil samples under three different horticultural management practices were collected from the Xiaxiyang Or... Dissolved organic nitrogen (DON) represents a significant pool of soluble nitrogen (N) in soil ecosystems. Soil samples under three different horticultural management practices were collected from the Xiaxiyang Organic Vegetable and Fruit Farm, Shanghai, China, to investigate the dynamics of N speciation during 2 months of aerobic incubation, to compare the effects of different soils on the mineralization of ^14C-labeled amino acids and peptides, and to determine which of the pathways in the decomposition and subsequent ammonification and nitrification of organic N represented a significant blockage in soil N supply. The dynamics of N speciation was found to be significantly affected by mineralization and immobilization. DON, total free amino acids, and NH^+-N were maintained at very low levels and did not accumulate, whereas NO3^--N gradually accumulated in these soils. The conversion of insoluble organic N to low-molecular-weight (LMW) DON represented a main constraint to N supply, while conversions of LMW DON to NH4^+-N and NH4^+-N to NO3^--N did not. Free amino acids and peptides were rapidly mineralized in the soils by the microbial community and consequently did not accumulate in soil. Turnover rates of the additional amino acids and peptides were soil-dependent and generally followed the order of organic soil 〉 transitional soil 〉 conventional soil. The turnover of high-molecular-weight DON was very slow and represented the major DON loss. Further studies are needed to investigate the pathways and bottlenecks of organic N degradation. 展开更多
关键词 amino acids dissolved organic N MINERALIZATION N transformation PEPTIDES
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Theoretical Study on Mechanism and Kinetics of Reaction of O(^3p) with Propane 被引量:1
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作者 荆富强 曹剑炜 +3 位作者 刘小君 胡煜峰 马海涛 边文生 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期430-436,I0001,共8页
The reaction of C3H8+O(^3p)→C3HT+OH is investigated using ab initio calculation and dynamical methods. Electronic structure calculations for all stationary points are obtained using a dual-level strategy. The geo... The reaction of C3H8+O(^3p)→C3HT+OH is investigated using ab initio calculation and dynamical methods. Electronic structure calculations for all stationary points are obtained using a dual-level strategy. The geometry optimization is performed using the unrestricted second-order Moller-Plesset perturbation method and the single-point energy is computed us- ing the coupled-cluster singles and doubles augmented by a perturbative treatment of triple excitations method. Results indicate that the main reaction channel is C3Hs+O(^3p)→i- C3HT+OH. Based upon the ab initio data, thermal rate constants are calculated using the variational transition state theory method with the temperature ranging from 298 K to 1000 K. These calculated rate constants are in better agreement with experiments than those reported in previous theoretical studies, and the branching ratios of the reaction are also calculated in the present work. Furthermore, the isotope effects of the title reaction are calculated and discussed. The present work reveals the reaction mechanism of hydrogenabstraction from propane involving reaction channel competitions is helpful for the understanding of propane combustion. 展开更多
关键词 Reaction mechanism Thermal rate constant Variational transition state theory Isotope effect
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Gastrointestinal hormone abnormalities and G and D cells in functional dyspepsia patients with gastric dysmotility 被引量:27
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作者 Mei-RongHe Yu-GangSong Fa-ChaoZhi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第3期443-446,共4页
AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric ... AIM: To investigate the relationship between gastric dysmotility,gastrointestinal hormone abnormalities, and neuroendocrine cells in gastrointestinal mucosa in patients with functional dyspepsia (FD).METHODS: Gastric emptying was assessed with solid radiopaque markers in 54 FD patients, and the patients were divided into two groups according to the results, one with delayed gastric emptying and the other with normal gastric emptying. Seventeen healthy volunteers acted as normal controls. Fasting and postprandial plasma levels and gastroduodenal mucosal levels of gastrointestinal hormones gastrin, somatostatin (SS) and neurotensin (NT)were measured by radioimmunoassay in all the subjects.G cells (gastrin-producing cells) and D cells (SS-producing cells) in gastric antral mucosa were immunostained with rabbit anti-gastrin polyclonal antibody and rabbit anti-SS polyclonal antibody, respectively, and analyzed quantitatively by computerized image analysis.RESULTS: The postprandial plasma gastrin levels, the fasting and postprandial plasma levels and the gastric and duodenal mucosal levels of NT were significantly higher in the FD patients with delayed gastric emptying than in those with normal gastric emptying and normal controls. The number and gray value of G and D cells and the G cell/D cell number ratio did not differ significantly between normal controls and the FD patients with or without delayed gastric emptying.CONCLUSION: Our findings suggest that the abnormalities of gastrin and NT may play a role in the pathophysiology of gastric dysmotility in FD patients, and the abnormality of postprandial plasma gastrin levels in FD patients with delayed gastric emptying is not related to the changes both in the number and gray value of G cells and in the G cell/D cell number ratio in gastric antral mucosa. 展开更多
关键词 Functional dyspepsia Gastric emptying Gastrointestinal hormone abnormalities G cells D cells
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DYNAMIC CHANGES OF INORGANIC NITROGEN AND ASTAXANTHIN ACCUMULATION IN HAEMATOCOCCUS PLUVIALIS 被引量:2
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作者 刘建国 殷明炎 +2 位作者 张京浦 刘伟 孟昭才 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第4期358-364,共7页
This study on dynamic changes of culture color, astaxanthin and chlorophylls, inorganic N including N NO - 3, N NO - 2 and N NH + 4 in batch culture of Haematococcus pluvialis exposed to different additive nitrate con... This study on dynamic changes of culture color, astaxanthin and chlorophylls, inorganic N including N NO - 3, N NO - 2 and N NH + 4 in batch culture of Haematococcus pluvialis exposed to different additive nitrate concentration showed (1) ast/chl ratio was over 0.8 for brown and red algae, but was usually less than 0.5 for green and yellow algae; (2) N NO - 3, in general, was unstable and decreased, except for a small unexpected increase in nitrate enriched treatment groups; (3) measurable amounts of N NO - 2 and N NH + 4 were observed respectively with three change modes although no external nitrite and ammonia were added into the culture; (4) a non linear correlation between ast/chl ratio (or color) changes and the levels of N NO - 3 , N NO - 2 , N NH + 4 in H. pluvialis culture; (5) up and down variation of the ast/chl ratio occurred simultaneously with a perceptible color change from yellow to brown (or red) when N NO - 3, N NO - 2 and N NH + 4 fluctuated around 30, 5, 5 μmol/L respectively; (6) existence of three dynamic modes of N NO - 3, N NO - 2 and N NH + 4 changes, obviously associated with initial external nitrate; (7) the key level of total inorganic N concentration regulating the above physiological changes during indoor cultivation was about 50 μmol/L; and (8) 0.5-10 mmol/L of nitrate was theoretically conducive to cell growth in batch culture. 展开更多
关键词 Haematococcus pluvialis NITRATE NITRITE AMMONIA ASTAXANTHIN
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Nutrient Application Model Affects the Contents of Chlorophyll and Carotenoid in Functional Leaves of Early Rice
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作者 周升明 周旋 +5 位作者 陈雄鹰 彭建伟 蔡桂青 刘强 荣湘民 黄维 《Agricultural Science & Technology》 CAS 2013年第11期1603-1609,共7页
The objective of this study was to investigate the effects of different nutri-ent application models on the contents of chlorophyl and carotenoid in the functional leaves of early rice. Using rice cultivar Xiangzaoxia... The objective of this study was to investigate the effects of different nutri-ent application models on the contents of chlorophyl and carotenoid in the functional leaves of early rice. Using rice cultivar Xiangzaoxian45 as experimental materials, the experiment was performed by designing 6 treatments, i.e., T1 (fertilization without nitrogen), T2(local conventional fertilization), T3(fertilization for high yield and high effi-ciency), T4 (fertilization for super high yield), T5 (fertilization application for super high yield and high efficiency A) and T6 (fertilization application for super high yield and high efficiency B) in two experimental plots Yiyang and Xiangyin. The results showed that T3 respectively increased the contents of chlorophyl and carotenoid at fil ing stage by 29.27%, 38.20% and 13.16%, 30.12% in Yiyang and Xiangyin, as wel as yield of early rice by 4.20%, 4.80% to T2 on the condition of saving 20% ni-trogen fertilizer. Additional y, T5 and T6 on the condition of saving 16.7% nitrogen fertilizer by T4 increased the contents of chlorophyl and carotenoid of fil ing stage by 53.91%, 53.73% and 35.95%, 37.47% in Yiyang and Xiangyin, as wel as yield of early rice by 16.60%, 18.75% to T2 in Yiyang; increased the contents of chlorophyl and carotenoid at fil ing stage by 57.82%, 56.80% and 54.88%, 57.03% in Yiyang and Xiangyin, as wel as yield of early rice 10.10%, 6.75% to T2 in Xiangyin. More-over, there was a significant correlation or an extremely significant correlation be-tween yield and the contents of chlorophyl and carotenoid at different soil fertility level (P〈0.05 or P〈0.01). Therefore, nutrient application plays an important role in the contents of chlorophyl and carotenoid in the functional leaves of early rice. 展开更多
关键词 Early rice Nutrient application model Chlorophyll content Carotenoidcontent Dynamic change
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Oribatid Use as Bioindicateur of Environment: Case of Galumna sp. and Scheloribates sp. (Acari: Oribatida)
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作者 Ghezali Djelloul Harkat Hafsa 《Journal of Life Sciences》 2012年第5期518-527,共10页
Environmental characteristics are often the factors that determine the distribution of species in nature. However, species response vis-A-vis these factors differs. For a better understanding of the phenomenon, we hav... Environmental characteristics are often the factors that determine the distribution of species in nature. However, species response vis-A-vis these factors differs. For a better understanding of the phenomenon, we have conducted this study which consists of following the spatio-temporal evolution of two species of Oribatida (Scheloribates sp. and Galumna sp.). The sites which have been the subject of this study, are situated in different bioclimatic zones presenting a very different climatic, edaphic, nutritional, and altitudinal characteristics. The variability of ecological factors showed that the behavior of two species differs. Indeed, Scheloribates sp. is present in all sites except in Biskra whereas Galumna sp. is present only in sites belonging to humid and sub humid bioclimatic zones. Moreover, Scheloribates sp. appears more tolerant of environmental changes while Galumna sp. is more stringent and its presence is marked only in the sites where ecological conditions are better. Thus, it can be noted that the spatial and temporal distribution of oribatid is not only conditioned solely by environmental factors but also by intrinsic factors specific to each species. The specific behavior of Galumna sp. and the tolerance of Scheloribates sp. are interesting and can be the subject of bioindicator species that can inform us about the changes that effect whether natural or anthropogenic environment. 展开更多
关键词 ORIBATIDA ecological factors area bioclimatic spatiotemporal.
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Effects of chemical cues on larval survival,settlement and metamorphosis of abalone Haliotis asinina 被引量:2
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作者 王小兵 白洋 黄勃 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1261-1265,共5页
Low larval survival,poor settlement,and abnormal metamorphosis are major problems in seed production of donkey-ear abalone Haliotis asinina.We examined the effects of chemical cues including epinephrine,nor-epinephrin... Low larval survival,poor settlement,and abnormal metamorphosis are major problems in seed production of donkey-ear abalone Haliotis asinina.We examined the effects of chemical cues including epinephrine,nor-epinephrine,and serotonin on larval survival,settlement,and metamorphosis in order to determine the possibility of using these chemicals to induce the problems.The results show that epinephrine could enhance metamorphosis rate at 10-6 mol/L only but higher concentrations(10-3-10-4 mol/L);and nor-epinephrine could inhibit the performance significantly,and serotonin could increase significantly the performance at a wide-range concentration(10-3-10-6 mol/L).Treatment with serotonin at 10-5 mol/L for 72 hours resulted in the highest settlement rate(42.2%) and survival rate(49.3%),while at 10-4 mol/L for 72 hours resulted in the highest metamorphosis rate(38.8%).Therefore,serotonin may be used as a fast metamorphosis inducer in abalone culture. 展开更多
关键词 EPINEPHRINE nor-epinephrine SEROTONIN settlement survival METAMORPHOSIS Haliotis asininaLinnaeus
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Dynamic Changes,Regional Differences,and Influencing Factorsof CO_2 Emission Performance in China 被引量:2
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作者 Wang Qunwei Zhou Peng Zhou Dequn 《Chinese Journal of Population,Resources and Environment》 2011年第3期47-57,共11页
This paper proposes to use DEA models with undesirable outputs to construct the Malmquist index that can be use to investigate the dynamic changes of CO 2 emission performance.With the index,the authors have measured ... This paper proposes to use DEA models with undesirable outputs to construct the Malmquist index that can be use to investigate the dynamic changes of CO 2 emission performance.With the index,the authors have measured the CO 2 emission performance of 28 provinces and autonomous regions in China from 1996 to 2007;with the convergence theory and panel data regression model,the authors analyze the regional differences and the influencing factors.It is found that the performance of CO 2 emissions in China has been continuously improved mainly due to the technological progress,and the average improvement rate is 3.25%,with a cumulative improvement rate of 40.86%.In addition,the CO 2 emission performance varies across four regions.As a whole,the performance score of eastern China is the highest.The northeastern and central China has relatively lower performance scores,and the western China is relatively backward.The regional differences are decreasing,and the performance of CO 2 emissions is convergent.The influence of some factors on the performance of CO 2 emissions is significant,such as the level of economic development,the level of industrial structure,energy intensity,and ownership structure.The influence of some factors,such as opening-up to the outside world,on the performance of CO 2 emissions is not significant.. 展开更多
关键词 carbon dioxide undesirable output Malmquist index CONVERGENCE panel date model
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Dynamic Evolvement of Agricultural System and Typical Patterns of Modern Agriculture in Coastal China:A Case of Suzhou 被引量:10
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作者 ZHAI Rongxin LIU Yansui 《Chinese Geographical Science》 SCIE CSCD 2009年第3期249-257,共9页
Based on dynamic theory of system, agriculture is a complex system composed by element, structure, function and development. Firstly, this paper analyzes their connotation and relationship, which could be simply descr... Based on dynamic theory of system, agriculture is a complex system composed by element, structure, function and development. Firstly, this paper analyzes their connotation and relationship, which could be simply described that in virtue of element integrating and structure optimizing, agricultural system may achieve multifunctionality to meet increasingly diverse demands. As a case study of Suzhou, it concludes that Suzhou has a LP-dependence on agricultural element, and the growth extent of agricultural productivity correlates to the ratio of agricultural labor reduc- ing rate to farmland reducing rate. Agricultural structure of Suzhou changed with time, and in the early 1980s and 2000s it was most notable. Correspondingly, agricultural function has experienced a succession process: 'production', 'production-living', and 'production-living-ecology'. At last, based on questionnaires and interviews, some new characteristics and problems of agricultural development in coastal developed region of China have been put forward. Meanwhile, some typical patterns of modern agriculture in Suzhou which adapt to system evolving are also brought up such as export-oriented agriculture, enterprises-leading agriculture, agricultural science and technology parks, characteristic and stereoscopic agriculture, tourism and sightseeing agriculture. 展开更多
关键词 modern agriculture agricultural system SUZHOU coastal China
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Is the advantage of coronary bypass graft surgery over percutaneous coronary intervention in diabetic patients with severe multivessel disease influenced by the status of insulin requirement? 被引量:1
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作者 Beom Jun Lee Peter Herbison Cheuk-Kit Wong 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2014年第1期83-89,共7页
Several studies have shown that coronary artery bypass graft surgery (CABG) is superior to percutaneous coronary intervention (PCI) in patients with diabetes and multi-vessel disease. Whether this advantage of CAB... Several studies have shown that coronary artery bypass graft surgery (CABG) is superior to percutaneous coronary intervention (PCI) in patients with diabetes and multi-vessel disease. Whether this advantage of CABG over PCI is confined to diabetics who require insulin is unknown. We review the published literature comparing CABG with PCI in diabetics including 8 cohorts and 4,786 patients. There was a lower rate for all-cause mortality (Relative risk (RR): 0.78, 95% confidence interval (CI): 0.62-0.99), and for major adverse cardiac and cerebrovascular events (MACCE, RR: 0.59, 95% CI: 0.47-0.75) for CABG compared to PCI. Composite outcome of mortality, myocardial infarction and stoke was similar between CABG and PCI (RR: 0.87, 95% CI: 0.54-1.42). Visual inspection of the forest plots showed that in most analyses, the point estimates of the RR are similar between the insulin requiring group and non-insulin requiring group. On meta-regression, there was no interaction between status of insulin requirement and revascularization strategies (P 〉 0.05 for all). The pre- sented data on the still unpublished analysis of the FREEDOM trial showed similar results. Thus, in the current era, CABG is superior to PCI with lower mortality and MACCE rates, but the state of insulin requirement had no effect on the outcomes from the two revascularization strategies. 展开更多
关键词 Percutaneous coronary intervention Coronary artery bypass graft surgery Diabetes mellims INSULIN Multivessel disease
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Vegetation Dynamics and Its Relationship with Climatic Factors in the Changbai Mountain Natural Reserve 被引量:5
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作者 H0U Guanglei ZHANG Hongyan WANG Yeqiao 《Journal of Mountain Science》 SCIE CSCD 2011年第6期865-875,共11页
This study examined the temporal variation of the Normalized Difference Vegetation Index (NDVI) and its relationship with climatic factors in the Changbai Mountain Natural Reserve (CMNR) during 2000 - 2009. The re... This study examined the temporal variation of the Normalized Difference Vegetation Index (NDVI) and its relationship with climatic factors in the Changbai Mountain Natural Reserve (CMNR) during 2000 - 2009. The results showed as follows. The average NDVI values increased at a rate of 0.0024 year-1. The increase rate differed with vegetation types, such as 0.0034 year-1 for forest and 0.0017 year-1 for tundra. Trend analyses revealed a consistent NDVI increase at the start and end of the growing season but little variation or decrease observed in July during the study period. The NDVI in CMNR showed a stronger correlation with temperature than with precipitation, especially in spring and autumn. A stronger correlation was observed between NDVI and temperature in the tundra zone (2,000-2,600m) than in the coniferous forest (1,100-1,700m) and Korean pine-broadleaved mixed forest (7oo-1,1oom) zones. The results indicate that vegetation at higher elevations is more sensitive to temperature change. NDVI variation had a strong correlation with temperature change (r=0.7311, p〈0.01) but less significant correlation with precipitation change. The result indicates that temperature can serve as a main indicator of vegetation sensitivity in the CMNR. 展开更多
关键词 Changbai Mountain Natural Reserve Remote sensing SPOT/VGT NDVI Climatic factors
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Potential Applications of X-ray Fluorescence Core Scanner in Elemental Analyses of the Muddy Sediments on the Coastal Shelves of China and in Ecological Study 被引量:2
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作者 ZHOU Xin SUN Liguang +1 位作者 LIU Yi WANG Yuhong 《Journal of Ocean University of China》 SCIE CAS 2013年第4期619-623,共5页
Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study... Large areas of muddy sediments on the coastal shelves of China provide important samples for studying climate and ecological changes. Analysis of a large number of such samples, which is essential for systematic study on environmental information recorded in mud areas because of complicated sedimentary environment and variable sedimentary rate, requires a fast and economical method. In this study, we investigated the potential of X-ray fluorescence core scanner (XRFS), a fast analytical instrument for measuring the elemental concentrations of muddy sediments, and observed a significant correlation between the element concentrations of muddy sediments determined by regular X-ray fluorescence spectrometer (XRF) and XRFS, respectively. The correlations are mainly determined by excitation energy of elements, but also influenced by solubility of element ions. Furthermore, we found a striking link between A1 concentrations and marine-originated organic carbon (MOC), a proxy of marine primary productivity. This indicates that MOC is partly controlled by sedimentary characteristics. Therefore, XRFS method has a good potential in fast analysis of a large number of muddy sediment samples, and it can also be used to calibrate MOC in ecological study of coastal seas. 展开更多
关键词 X-ray fluorescence core scanner X-ray fluorescence spectrometer muddy sediment marine-originated organic carbon ecological study
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Concentrations of gastric mucosal cytokines in children with food allergy and Helicobacterpylori infection
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作者 El(z|.)bieta Maciorkowska Anatol Panasiuk Maciej Kaczmarski 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第43期6751-6756,共6页
AIM: To measure the concentrations of chosen cytokines in the antrum mucosa depending on the kind of harmful pathogenic factors and to compare the concentrations with the values of controls without allergy and coexis... AIM: To measure the concentrations of chosen cytokines in the antrum mucosa depending on the kind of harmful pathogenic factors and to compare the concentrations with the values of controls without allergy and coexisting Helicobacter pylori (H pylori) infection. METHODS: The patients (97 children) were divided into three groups according to the data obtained from the case history, to the main cause of the disease and to the dominant clinical symptoms. Group Ⅰ: children with food allergy (Fa); group Ⅱ: children infected with H pylori; group Ⅲ (control group): children with functional disorders of the alimentary tract (without Fa and Hp infection). H pylori infection was determined by the presence of anti-Hp antibodies in serum (ELISA method) and urease test performed during endoscopic examination. Cytokine concentration in homogenates of gastric mucosa was detected by ELISA method. RESULTS: The IL-2 concentration in gastric mucosa bioptates was the highest in children with Hp infection (116.5±179.5 pg/mg of the protein) and Fa and Hp infection (98.1±101.0 pg/mg), while decreased in children with Fa (44.8±50.3 pg/mg) and controls (45.7±23.5 pg/mg). The lowest mean concentration of IFN-y was observed in children with Hp infection (18.9±16.4 pg/mg), with Fa and Hp infection (25.5±27.7 pg/mg), with Fa (40.6±39.7 pg/mg) and controls (49.9±33.4 pg/mg). The highest IL-4 concentrations were observed in children with Hp infection (35.3±52.8 pg/mg) and in children with Fa and Hp infection (37.2±51.7 pg/mg), while lower IL-4 concentration (23.64-35.8 pg/mg) was found in children with Fa compared to the controls (22.7±13.8 pg/mg). The analysis of IL-4 concentrations in children with Hp infection regarding the intensity of gastritis showed the highest value (62.2±61.2 pg/mg) in mild and moderate gastritis. The concentrations of IL-5 in the gastric mucosa of children with or without Fa did not differ significantly and were comparable to the control group. The highest mean IL-8 value was observed in Hp-infected children with or without Fa. The highest concentration of mucosal IL-10 was detected in children with Hp infection (79.3±41.2 pg/mg) and decreased in children with Fa and Hp infection (50.1±18.8 pg/mg) and in children with Fa (39.9±35.5 pg/mg). The intensity and activity of the inflammation did not affect IL-10 concentrations in the gastric mucosa. In children with Hp infection, TNF-α concentration was the highest (45.9±49.3 pg/mg) and in children with Fa and Hp infection was low (45.3±32.6 pg/mg), whereas decreased in children with Fa (21.7±34.2 pg/mg) and in controls (31.6±14.5 pg/mg). CONCLUSION: The morphological changes of the gastric mucosa in children with Hp infection are comparable to those in children with Fa and coexisting Hp infection. Cytokine concentration in children with Fa and Hp infection is significantly different in IFN-7, IL-2, IL-8, and TNF-α. 展开更多
关键词 Mucosal cytokines Food allergy Helicobacterpylori dehydrogenase complex
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Between and Within-Farm Variability in Soil Fertility Management and Status in the Central Highlands of Kenya
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作者 J. M. Muthamia D. N. Mugendi +1 位作者 J. B. Kung'u B. Vanlauwe 《Journal of Agricultural Science and Technology(A)》 2011年第2X期270-284,共15页
The processes of nutrient depletion and soil degradation within smallholder farms of central Kenya are spatially heterogeneous, determined by both biophysical and socio-economic factors. A monitoring study involving n... The processes of nutrient depletion and soil degradation within smallholder farms of central Kenya are spatially heterogeneous, determined by both biophysical and socio-economic factors. A monitoring study involving nutrient stocks, flows and balances was conducted in central Kenya to explore between and within-farm variability in soil fertility management and identify spatial niches for targeting soil fertility management strategies. Focus group discussions were conducted and farms grouped into 3 farm types (rich, medium and poor). Nine case-study farms - three from each of the farm types - were randomly selected from the 50 farms studied, for detailed resource flow mapping. The farms were visited to record movement of nutrients inputs using a monitoring protocol covering soil, crops, livestock, and socio-economic aspects of the farm. Soil in different plots were sampled at a depth of 0-20 cm and analyzed for texture, pH, C, N, available P, exchangeable K+, Mg2+ and Ca2+. Results revealed that wealthy farmers added an average of 51.3 kg/ha N, 37 kg/ha P, and 244 kg/ha K, compared to 25.9 kg/ha N, 14.5 kg/ha P and 50.7 kg/ha K for the poor farmers. In all farm types, home fields received more nutrient inputs compared to the outfields. Consequently, maize grain yields, partial nutrient balances and soil nutrient stocks were significantly higher in wealthy farms and home fields compared to poor farms and outfields, respectively. These results imply that different soil management strategies are required to achieve similar yields on the different field and farm types and avert soil degradation. 展开更多
关键词 Soil fertility home fields outfields soil degradation soil nutrient budgets.
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Relationship between urinary nephrin and urinary albumin changes in diabetic rats and effects of Yiqiyangyinhuayutongluo Recipe 被引量:8
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作者 李黎莉 陈志强 +5 位作者 王月华 张江华 尹智炜 李林林 张雪云 王凤丽 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第2期278-282,共5页
OBJECTIVE:To investigate the dynamic changes of urinary nephrin,and the relationship between it and urinary albumin excretion rate(UAER) in a diabetic rat model,as well the effects of yiqiyangyinhuayutongluo recipe.ME... OBJECTIVE:To investigate the dynamic changes of urinary nephrin,and the relationship between it and urinary albumin excretion rate(UAER) in a diabetic rat model,as well the effects of yiqiyangyinhuayutongluo recipe.METHODS:Diabetic model was induced by high fat diet combined with low-dose Streptozotocin(STZ) in rats.Normal group(NG),model group(MG),and yiqiyangyinhuayutongluo recipe treated group(YHTG) were set.Gastrointestinal Yiqiyangyinhuayutongluo recipe was administered once daily for 32 w.At the end of the 2nd w(2w),8w,16w,and 32w,fasting blood glucose(FBG),UAER and 24h urinary nephrin(U-nephrin) were detected.RESULTS:Compared with NG,FBG in MG increased notably(P<0.05).Compared with MG,FBG of YHTG reduced slowly,and the difference was significant(P<0.05) since 16w.U-nephrin and UAER in MG increased significantly from 2w,peaked at 16w,lessened in different degree at 32w,but were still higher than NG.The correlation analysis showed that there was a significant positive correlation between U-nephrin and UAER at different time,the correlation coefficient as r>0.9,and P<0.05.Compared with MG,U-nephrin and UAER in YHTG decreased markedly(P<0.05) except for U-nephrin at 8w.CONCLUSIONS:U-nephrin and UAER in diabetic rat model have a positive linear correlation.Yiqiyangyinhuayutongluo recipe can reduce UAER markedly,and preventing the lose of nephrin in urine maybe one of the mechanisms. 展开更多
关键词 Yiqiyangyinhuayutongluo recipe Diabetic nephropathy Urinary nephrin Urinary albumin excretion rate SD rats
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Mapping Nuclear Decay to a Complex Network 被引量:1
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作者 李永 方锦清 刘强 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第3期490-492,共3页
Nuclear decay is investigated by the view of network science and the relationship of nuclear decay among different radionuclide can be mapped to a network topology directly.The network includes 1410 nodes and 1275 edg... Nuclear decay is investigated by the view of network science and the relationship of nuclear decay among different radionuclide can be mapped to a network topology directly.The network includes 1410 nodes and 1275 edges.The average degree of the network of nuclear decay is about 1.8,the cumulative degree distribution still meets the typical power-law distribution,and the corresponding exponent is about 4.1.Not considering their dynamic behavior,the fitting parameters of the nuclear decay network are obtained according to the LUHNM theory proposed by our group before.Their cumulated degree distributions of the nuclear decay network match well.The idea and method may provide a new way to study some other problems of nuclear physics. 展开更多
关键词 nuclear decay complex network LUHNM
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The Characteristics and Driving Factors of the Spatio-temporal Dynamic Evolution of Tourism Ecological Security in the Silk Road Economic Belt
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作者 WANG Shu LIU Fenglian +1 位作者 YANG Lei CAI Wei 《Journal of Resources and Ecology》 2024年第4期1054-1067,共14页
The exploration of ecological safety in tourism sites can provide a concrete path for sustainable tourism development in a region.Based on the“Driver-Pressure-State-Impact-Response”(DPSIR)model,we constructed an ind... The exploration of ecological safety in tourism sites can provide a concrete path for sustainable tourism development in a region.Based on the“Driver-Pressure-State-Impact-Response”(DPSIR)model,we constructed an index system for the evaluation of tourism ecological security(TES)in the Silk Road Economic Belt(SREB)from 2005 to 2020.This index system was used to explore the characteristics of spatial and temporal dynamic evolution with the help of entropy weight TOPSIS method,dynamic index of TES and Markov probability transfer matrix,and a standard deviational ellipse(SDE)model and GM(1,1)model were constructed for spatial pattern analysis and prediction.The results indicate four key aspects of this system.(1)In terms of spatiotemporal evolution,the tourism ecological safety index(TESI)of the SREB increased,the TES levels of the northwestern and southwestern provinces and cities differed significantly,and the quality conditions of TES in the southwestern provinces and cities were better than in the northwest.(2)In terms of dynamic evolutionary characteristics,the speed of change at each level of the SREB was slow,but the level of TES has improved.The TES level has not shifted by leaps and bounds,and the shifts in the level type show“path dependence”and“self-locking”effects.(3)In terms of spatial and temporal distribution patterns,the spatial pattern of TES in the SREB is a“northwest-southeast”movement trend,and the spatial distribution appeared as“aggregation”from 2005 to 2020.The prediction results show that the center of gravity of TES in the SREB will shift to the southeast from 2025 to 2035,and the spatial spillover effect will be reduced.(4)In terms of driving factors,the number of star-rated hotels,and the amounts of industrial wastewater emissions,tourism foreign exchange earnings,forest coverage,and other parameters are the key factors affecting TES,and the booming tourism industry requires the interconnection and interpenetration of various factors.The results of this study can provide a reference for tourism development and ecological environmental protection in the Silk Road Economic Belt. 展开更多
关键词 tourism ecological security spatial-temporal evolution drivers Geo-detector the Silk Road Economic Belt
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