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Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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Science china(Life Sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2, LIU RuiFang2, WANG AnRu3, DU LiLi1 & DENG XueMei1 1 college of Animal Science and Technology, china Agricultural university, Beijing 100094, china 2 vocational and technologic college, inner mongolia agriculture university, baotou 014109, china 3 college of Veterinary Medicine, china Agricultural university, Beijing 100094, china college of Animal Science and Technology China Agricultural University Beijing China vocational and technologic college Inner Mongolia Agriculture University Baotou China college of Veterinary Medicine China Agricultural University Beijing China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

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An improved SIFT Algorithm for Feature Points matching of dairy cow images

An improved SIFT Algorithm for Feature Points matching of da...

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亚洲精细农业与计算机农业应用联合大会

作者： Lizhong Wang vocational and Technical college inner mongolia Agricultural university Hohhot inner mongolia china Shuoshi Ma college of Mechanical and Electrical Engineering inner mongolia Agricultural university Hohhot inner mongolia china Heru Xue Zhenjie Hou college of Computer and Information Engineering inner mongolia Agricultural university Hohhot inner mongolia china

The conformation is the main parameter in dairy cow appraisal;hence, it is necessary for the measuring and evaluating of dairy conformation to use machine vision technology in 3D reconstruction. The feature points detecting and matching are the pivotal steps in 3D reconstruction. The conventional SIFT feature points matching algorithm has shortcomings of too large search area and low efficiency, An improved SIFT feature points matching algorithm is proposed to reduce the search range from both row and column directions based on binocular vision principle. 2.7 times of in speed by the improved algorithm has been shown in the experiments compared with that of the conventional algorithm with the same matching precision.

关键词： diary cow conformation feature points detecting feature points matching SIFT algorithm

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Molecular Simulation of the Complex of Konjac Glucomannan-Borate in Water

Molecular Simulation of the Complex of Konjac Glucomannan-Bo...

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经济发展方式转变与自主创新——第十二届中国科学技术协会年会

作者： Wenjie JIAN 1,2,Yuan ZENG 2,Jie PANG 2 (1.college of Food Science,Fujian agriculture and Forestry university,Fuzhou 350002,china 2.Department of Biological Technology,Xiamen Ocean vocational college,Xiamen 361012,Fujian,china)

The formation of Konjac Glucomannan-Borate complex in water solution has been investigated by experimental and molecular simulation *** energy,radical distribution function of borate anion (B(OH)4-),and mean square displacement of the complex were studied during the molecular *** results indicate that one type of helical complex can be formed based on the hydrogen bonds between borate anion and helical chain of *** hydrogen bond is formed by the interaction of borate anion and -OH groups on C (6) of mannose and *** has little effect on the helical conformation of the *** was proposed that the complex can form gel through the aggregation arrangement of helical chain.

关键词： Konjac glucomannan borax molecular docking molecular dynamic simulation complex

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Mineral Coated Fertilizer Effect on Nitrogen-Use Efficiency and Yield of Wheat

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Pedosphere 2005年第4期15卷 526-531页

作者： LI Jian-Yun HUA Quan-Xian TAN Jin-Fang ZHOU Jian-Min HOU Yan-Lin L Department of Soil Environmental Science Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 （China）. State Key Laboratory of Soil and Sustainable agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China） college of agriculture Henan Agricultural University Zhengzhou 450002 （China）

A field experiment with winter wheat （Triticum aestivurn L.） was conducted on a silt loam calcaric endorusti-ustic Cambosols derived from the Yellow River alluvial deposits in Henan, china, from 2001 to 2002 to evaluate N recovery and agronomic performance of different mineral coated fertilizers （MiCFs） compared to normal urea used in wheat cropping systems under field conditions. Five treatments, including CK （check, no N fertilizer）, urea and three different MiCFs at an equivalent N application rate were established in a randomized complete block design. N release from MiCFs in soil was more synchronous with the N requirement of wheat throughout the growth stages than that from urea, with grain yield of the MiCF treatments significantly higher （P 〈 0.05） than that of the treatment urea. Correspondingly, the N recovery rate was greater for all MiCFs compared to urea, increasing from 32.8% up to 50.1%. Due to its high recovery and low cost, use of the mineral coated N fertilizers was recommended instead of the polymer coated N fertilizers.

关键词： mineral coated fertilizer N recovery urea winter wheat

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Study on the Hydration Shell of Single-Helical of Konjac Glucomannan

Study on the Hydration Shell of Single-Helical of Konjac Glu...

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经济发展方式转变与自主创新——第十二届中国科学技术协会年会

作者： Jie PANG 1,Wenjie JIAN 1,2,Minna YAO 1,Huimin LIN 1,Aijun FENG 1,Yuan ZENG 1 (1 college of Food Science,Fujian agriculture and Forestry university,Fuzhou 350002,china 2 Department of biological technology,Xiamen Ocean vocational college,Xiamen 361012,Fujian,china)

The local maxima of water density in the space near the single-helical of Konjac glucomannan,as well as the dominant conformation of the system was studied by molecular dynamics under the water *** results indicate that the hydration shell,potential energy,and its hydrogen bond network with water bridges of the left-handed single-helix conformation was favored compared to those of right-handed single-helix *** work suggests that the left-handed single-helix conformation was the dominant conformation of KGM in water environment.

关键词： Konjac Glucomannan single-helical structure hydration shell molecular dynamic simulation

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小流域土壤养分流失机理与土地覆盖格局演变

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水土保持研究 2005年第6期12卷 218-221页

作者：胡婧丛伟闫锋张兴昌杨凌职业技术学院西北农林科技大学资源环境学院陕西杨陵712100

小流域土壤养分流失与土地利用格局演变关系的研究作为陆地-大气相互作用、全球变化等研究的主要基础内容,是一个正在形成的、具有综合性和交叉性的学科生长点。论述了该项研究的重要性、小流域土壤养分流失机理与土地覆盖格局演变的关... 详细信息

小流域土壤养分流失与土地利用格局演变关系的研究作为陆地-大气相互作用、全球变化等研究的主要基础内容,是一个正在形成的、具有综合性和交叉性的学科生长点。论述了该项研究的重要性、小流域土壤养分流失机理与土地覆盖格局演变的关系、小流域土壤养分流失模型和今后的研究展望,以期推动土壤环境科学的发展。

关键词：小流域土壤养分流失机理土地覆盖格局演变

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苯丙噻二唑诱导辣椒抗白粉病机制研究

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北方园艺 2016年第16期 113-118页

作者：莫熙礼蒋选利黔西南民族职业技术学院生物工程系贵州兴义562400 贵州大学农学院贵州贵阳550025

以花溪辣椒、遵义辣椒为试材,辣椒白粉病菌为供试菌,苯丙噻二唑(BTH)为诱导剂,采用喷施接种法,研究了BTH诱导辣椒对白粉病产生抗性的作用机制。结果表明:不同浓度BTH均可以诱导辣椒对白粉病产生抗性,浓度为0.20mmol·L-1时诱导效果最佳... 详细信息

以花溪辣椒、遵义辣椒为试材,辣椒白粉病菌为供试菌,苯丙噻二唑(BTH)为诱导剂,采用喷施接种法,研究了BTH诱导辣椒对白粉病产生抗性的作用机制。结果表明:不同浓度BTH均可以诱导辣椒对白粉病产生抗性,浓度为0.20mmol·L-1时诱导效果最佳,防治效果为81.82%;BTH-接菌处理的辣椒叶片过氧化物酶(POD)、多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)活性明显增加;BTH-接菌、BTH-未接菌和CK-接菌处理都能诱导辣椒叶片几丁质酶和β?1,3-葡聚糖酶活性的升高,但CK-接菌处理增加幅度较小。BTH不影响白粉病菌孢子萌发和附着胞子的产生,却能有效抑制菌丝的生长,表现为菌丝生长缓慢和菌丝的侧枝数减少。通过扫描电镜观察,发现CK-接菌处理在24h后,辣椒叶片保护层开始被溶解,BTH-接菌处理的辣椒在接菌48h后才出现该现象,说明BTH能产生阻碍或延迟菌丝破坏的保护层物质。

关键词：苯丙噻二唑(BTH) 辣椒防御酶

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