|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Application of Land-use Change Model in Guiding Regional Planning:A Case Study in Hun-Taizi River Watershed,Northeast China显示文摘This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River watershed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small regional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ecological protection over the next 20 years. The simulated results under UP scenario in 2020 were compared with the planning map to assess the feasibility of using land-use change model to guide regional planning. Results show that forest land, dry farmland, paddy, and shrub land were the main land-use categories. Paddy and dry farmland being converted to urban area and rural settlement characterized the land-use change from 1988 to 2004. The main land-use categories changed over time. Landscape-pattern fragmentation will be worse under HT and UP scenarios, but better in EP scenario. The comparing results of simulated map with planning map in 2020 show that land-use change model is powerful tool to guide regional planning. Land-use scenarios can support regional planning and policy-making through analyzing future consequences scientifically. | LIU Miao HU Yuanman ZHANG Wei ZHU Junjun CHEN Hongwei XI Fengming | 2011 | Chinese Geographical Science2011，21，5： | 10 |
| 2 | Effects of magnesium on the performance of sows and their piglets显示文摘The objective of this study was to evaluate the effects of supplemental magnesium(Mg) on the performance of gilts and parity 3 sows and their piglets.Fifty-six gilts(Trial 1) and 56 sows(Trial 2) were assigned to one of 4treatments according to their mating weight,respectively.The treatments comprised corn-soybean meal based gestation and lactation diets(0.21%magnesium) supplemented with 0,0.015,0.03,or 0.045%Mg from mating until weaning.The results showed that magnesium supplementation significantly(P < 0.05) reduced the weaning to estrus interval in both gilts and sows.There were significant effects(P < 0.05) of supplemental magnesium on the total number of piglets born,born alive and weaned in sows.In late gestation and lactation,the digestibility of crude fiber(quadratic effects,P< 0.05),and crude protein(P< 0.05),were significantly influenced by magnesium in gilts and sows,respectively.There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows(P< 0.05) during both early and late gestation.The apparent digestibility of gross energy was increased for sows in late gestation(P< 0.05),and lactation(quadratic effects,P< 0.05).At farrowing and weaning,serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased(P < 0.05).Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation(P< 0.05).The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium(P < 0.05).In addition,growth hormone levels were linearly elevated(P< 0.05) in the serum of piglets suckling sows.Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows,and the suitable supplemental dose ranged from 0.015%to 0.03%. | Jianjun Zang Jingshu Chen Ji Tian Aina Wang Hong Liu Shengdi Hu Xiangrong Che Yongxi Ma Junjun Wang Chunlin Wang Guanghua Du Xi Ma | 2015 | Journal of Animal Science and Biotechnology2015，6，1： | 3 |
| 3 | Alpha-ketoglutarate inhibits glutamine degradation and enhances protein synthesis in intestinal porcine epithelial cells显示文摘 | Kang Yao Yulong Yin Xilong Li Pengbin Xi Junjun Wang Jian Lei Yongqing Hou Guoyao Wu | 2012 | Amino Acids2012，，6： | 1 |
| 4 | Integrative analysis of indirect calorimetry and metabolomics profiling reveals alterations in energy metabolism between fed and fasted pigs显示文摘Background: Fasting is a simple metabolic strategy that is used to estimate the maintenance energy requirement where the energy supply for basic physiological functions is provided by the mobilization of body reserves.However, the underlying metabolic components of maintenance energy expenditure are not clear. This study investigated the differences in heat production(HP), respiratory quotient(RQ) and plasma metabolites in pigs in the fed and fasted state, using the techniques of indirect calorimetry and metabolomics.Methods: Nine barrows(45.2 ± 1.7 kg BW) were fed corn-soybean based meal diets and were kept in metabolism crates for a period of 14 d. After 7 d adaptation, pigs were transferred to respiratory chambers to determine HP and RQ based on indirect calorimetry. Pigs were fed the diet at 2,400 k J ME/(kg BW0.6·d) during d 8 to 12. The last 2 d were divided into 24 h fasting and 48 h fasting treatment, respectively. Plasma samples of each pig were collected from the anterior vena cava during the last 3 d(1 d while pigs were fed and 2 d during which they were fasted).The metabolites of plasma were determined by high-resolution mass spectrometry using a metabolomics approach.Results: Indirect calorimetry analysis revealed that HP and RQ were no significant difference between 24 h fasting and 48 h fasting, which were lower than those of fed state(P < 0.01). The nitrogen concentration of urine tended to decrease with fasting(P = 0.054). Metabolomics analysis between the fed and fasted state revealed differences in15 compounds, most of which were not significantly different between 24 h fasting and 48 h fasting. Identified compounds were enriched in metabolic pathways related to linoleic acid metabolism, amino acid metabolism,sphingolipid metabolism, and pantothenate and Co A biosynthesis.Conclusion: These results suggest that the decreases in HP and RQ of growing pigs under fasting conditions were associated with the alterations of linoleic acid metabolism and amino acid metabolism. The integrative analysis also revealed that growing pigs under a 24-h fasting were more appropriate than a 48-h fasting to investigate the metabolic components of maintenance energy expenditure. | Hu Liu Yifan Chen Dongxu Ming Ji Wang Zhen Li Xi Ma Junjun Wang Jaap van Milgen Fenglai Wang | 2018 | Journal of Animal Science and Biotechnology2018，9，3： | 1 |
| 5 | A family of three-port half-bridge converters for stand-alone renewable power system显示文摘 | Hongfei Wu Runruo Chen Junjun Zhang Yan Xi | | 0，，09： | 1 |
| 6 | The structure of 4-hydroxylphenylpyruvate dioxygenase complexed with 4-hydroxylphenylpyruvic acid reveals an unexpected inhibition mechanism显示文摘4-Hydroxyphenylpyruvate dioxygenase(HPPD)is an important target for both drug and pesticide discovery.As a typical Fe(II)-dependent dioxygenase,HPPD catalyzes the complicated transformation of 4-hydroxyphenylpyruvic acid(HPPA)to homogentisic acid(HGA).The binding mode of HPPA in the catalytic pocket of HPPD is a focus of research interests.Recently,we reported the crystal structure of Arabidopsis thaliana HPPD(At HPPD)complexed with HPPA and a cobalt ion,which was supposed to mimic the pre-reactive structure of At HPPD-HPPA-Fe(II).Unexpectedly,the present study shows that the restored At HPPD-HPPA-Fe(II)complex is still nonreactive toward the bound dioxygen.QM/MM and QM calculations reveal that the HPPA resists the electrophilic attacking of the bound dioxygen by the trim of its phenyl ring,and the residue Phe381 plays a key role in orienting the phenyl ring.Kinetic study on the F381 A mutant reveals that the HPPD-HPPA complex observed in the crystal structure should be an intermediate of the substrate transportation instead of the pre-reactive complex.More importantly,the binding mode of the HPPA in this complex is shared with several well-known HPPD inhibitors,suggesting that these inhibitors resist the association of dioxygen(and exert their inhibitory roles)in the same way as the HPPA.The present study provides insights into the inhibition mechanism of HPPD inhibitors. | Xiaoning Wang Hongyan Lin Junjun Liu Xinyun Zhao Xi Chen Wenchao Yang Guangfu Yang Chang-guo Zhan | 2021 | Chinese Chemical Letters2021，32，6： | 1 |
| 7 | Comprehensive analysis of antibacterial and anti-hepatoma activity of metabolites from jujube fruit显示文摘Jujube is one of the most produced dried fruits in China,and it is also a traditional Chinese medicine that enhances immunity and has anti-cancer activity.Jujube fruit is rich in phenolic compounds,but few reports are available on its biological activities.To evaluate the biological activities of the phenolic compounds in dried jujube fruit,the composition and content of metabolites in dried jujube fruit were determined by metabolomics,and the antibacterial and anticancer activities of the phenolic compounds were analyzed in dried jujube fruit.The results showed that 463 compounds were identified in dried‘Junzao’fruit,including 102 phenolic compounds.The in vitro activity test showed that the jujube phenolic metabolites had extensive antibacterial effects and caused disruption and nuclear sclerosis of hepatocellular carcinoma(HepG2)cells.Canonical correlation analysis showed that total phenolic content,quercetin-3-rutinose,and procyanidin B1 were the main active antibacterial and anticancer components.The study provides data supporting the application of dried jujube fruit in the development of functional foods,pharmaceuticals and cosmetics. | Qianqian Shi Xi Li Dajun Zhu Junjun Jiang Xingang Li | 2022 | Food Bioscience2022，47，3： | 1 |
| 8 | Soft magnetic property and magnetization reversal mechanism of Sm doped FeCo thin film for high-frequency application显示文摘 | XI Li DU Jihong ZHOU Junjun | 2012 | Thin Solid Films2012，520，16： | 1 |
| 9 | Identification of serum microRNAs for cardiovascular risk stratification in dyslipidemia subjects显示文摘 | Jia Wu Jiaxi Song Cheng Wang Dongmei Niu Hanqing Li Yuxiu Liu Lijuan Ma Ruijie Yu Xi Chen Ke Zen Qi Yang Chunni Zhang Chen-Yu Zhang Junjun Wang | 2014 | International Journal of Cardiology2014，，： | 1 |
| 10 | QM/MM study on the O_(2)activation reaction of 4-hydroxylphenyl pyruvate dioxygenase reveals a common mechanism forα-ketoglutarate dependent dioxygenase显示文摘The dioxygen activation catalyzed by 4-hydorxylphenyl pyruvate dioxygenase(HPPD)were reinvestigated by using hybrid quantum mechanics/molecular mechanics(QM/MM)approaches at the B3LYP/6-311++G(d,p):AMBER level.These studies showed that this reaction consisted of two steps including the dioxygen addition/decarboxylation and hetero O-O bond cleavage,where the first step was found to be rate-determining.The former step initially runs on a septet potential energy surface(PES),then switches to a quintet PES after crossing a septet/quintet minimum energy crossing point(MECP)5-7M2,whereas the rest step runs on the quintet PES.The reliability of our theoretical predictions is supported by the excellent agreement of the calculated free-energy barrier value of 16.9 kcal/mol with available experimental value of 16-17 kcal/mol.The present study challenges the widely accepted view which holds that the O2activation catalyzed byα-keto glutamate(α-KG)dioxygenase mainly runs on the quintet PES and provides new insight into the catalytic mechanism ofα-KG dioxygenase and/or other related Fe(Ⅱ)-dependent oxygenase. | Linhui Li Suitian Lai Hongyan Lin Xinyun Zhao Xin Li Xi Chen Junjun Liu Guangfu Yang Changguo Zhan | 2023 | Chinese Chemical Letters2023，34，5： | 0 |
| 11 | A Widely Applicable Method for Plant Genomic DNA Extraction显示文摘[Objective] This study aimed to explore a method for plant genomic DNA extraction,to provide guidance for rapid extraction of genomic DNA from plant tissues.[Method] Based on the published genomic DNA extraction methods,operation steps,reagent amount and processing time of SDS extraction method were optimized.[Result] A widely applicable method was established initially for genomic DNA extraction from various varieties of plants and various kinds of plant tissues.Quality of the extracted genomic DNA was relatively good,which meets the requirements for further operation.[Conclusion] This study provided guidance for rapid plant genomic DNA extraction. | Bin LI Lixia YU Junjun XI Yaping ZHANG Zerui GAO Bo YAN | 2012 | Agricultural Biotechnology2012，1，1： | 0 |
| 12 | Characterizing stand structure in a spruce forests:effects of sampling protocols显示文摘Spatial heterogeneity is an inherent characteristic of natural forest landscapes,therefore estimation of structural variability,including the collection and analyzing of field measurements,is a growing challenge for monitoring wildlife habitat diversity and ecosystem sustainability.In this study,we investigated the combined influence of plot shape and size on the accuracy of assessment of conventional and rare structural features in two young-growth spruce-dominated forests in northwestern China.We used a series of inventory schemes and analytical approaches.Our data showed that options for sampling protocols,especially the selection of plot size considered in structural attributes measurement,dramatically affect the minimum number of plots required to meet a certain accuracy criteria.The degree of influence of plot shape is related to survey objectives; thus,effects of plot shape differ for evaluations of the 'mean' or 'representative' stand structural conditions from that for the range of habitat(in extreme values).Results of Monte Carlo simulations suggested that plot sizes <0.1 ha could be the most efficient way to sample for conventional characteristics(features with relative constancy within a site,such as stem density).Also,0.25 ha or even larger plots may have a greater likelihood of capturing rare structural attributes(features possessing high randomness and spatial heterogeneity,such as volume of coarse woody debris) in our forest type.These findings have important implications for advisable sampling protocol(plot size and shape) to adequately capture information on forest habitat structure and diversity; such efforts must be based on a clear definition of which types are structural attributes to measure. | Jun Du WeiJun Zhao ZhiBin He JunJun Yang LongFei Chen Xi Zhu | 2015 | Research in Cold and Arid Regions2015，7，3： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员