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素数幂、双素数幂阶元的共轭类长的个数为4的有限群的结构
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作者 邵长国 蒋琴会 《数学年刊(A辑)》 CSCD 北大核心 2018年第1期1-6,共6页
设群G为一个有限群.如果群G中素数幂、双素幂阶元的共轭类长的集合为{1,p^a,m,p^bm},那么群G是可解的,其中a>b为正整数,p为素数且与m互素.进一步,给出了群G/Z(G)的结构,这是对文"Chen R F,Zhao X H.A criterion for a group to ... 设群G为一个有限群.如果群G中素数幂、双素幂阶元的共轭类长的集合为{1,p^a,m,p^bm},那么群G是可解的,其中a>b为正整数,p为素数且与m互素.进一步,给出了群G/Z(G)的结构,这是对文"Chen R F,Zhao X H.A criterion for a group to have nilpotent p-complements[J].Monatsh Math,2016,179(2):221-225"中定理A主要结论的一个推广. 展开更多
关键词 有限群 素数幂 双素幂阶元 共轭类长 2-Frobenius群
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Polypyrimidine Tract-Binding Protein Enhances Zika Virus Translation by Binding to the 5'UTR of Internal Ribosomal Entry Site
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作者 Moliduer Hamiti Xin-Tian Zhang +4 位作者 Rui-Min Zhu Yun-Peng Liu Bin Yin Peng-Cheng Shu Xiao-Zhong Peng 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第3期163-172,共10页
Objectives To identify the 5'untranslated region of Zika virus(ZIKV 5'UTR)RNA-binding proteins and to investigate the impact of the binding protein on the activity of internal ribosomal entry site(IRES)located... Objectives To identify the 5'untranslated region of Zika virus(ZIKV 5'UTR)RNA-binding proteins and to investigate the impact of the binding protein on the activity of internal ribosomal entry site(IRES)located in ZIKV 5'UTR and virus production.Methods Interacting proteins in U251 cells were captured using tRSA-tagged ZIKV 5'UTR RNA and tRSA-ZIKV 5'UTR RNA-binding proteins were visualized by SDS-PAGE silver staining,Subsequently,liquid chromatographytandem mass spectrometry(LC-MS/MS),bioinformatics analysis,and Western blot were used to identify the candidate proteins binding to ZIKV 5'UTR.Dicistronic expression assay and plaque forming assay were performed to analyze the effect of the binding protein on ZIKV IRES activity and ZIKV production,respecitvely.Results tRSA RNA pull-down assay,LC-MS/MS,and Western blot analysis showed that polypyrimidine tractbinding protein(PTB)bound to the ZIKV 5'UTR.Furthermore,dual luciferase reporter assay revealed that overexpression of PTB significantly enhanced the IRES activity of ZIKV(t=10.220,P<0.001),while PTB knockdown had the opposite effect(t=4.897,P<0.01).Additionally,virus plaque forming assay demonstrated that up-regulation of PTB expression significantly enhanced viral titer(t=6.400,P<0.01),whereas reducing PTB expression level weakened virus infectivity(t=5.055,P<0.01).Conclusion PTB positively interacts with the ZIKV 5'UTR and enhances IRES activity and virus production. 展开更多
关键词 internal ribosomal entry site polypyrimidine tract-binding protein Zika virus tRSA RNA pull-down dual-luciferase reporter assay
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Role of bisphosphonates in osteoporosis caused by adult growth hormone deficiency
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作者 CHENG Zhiling LI Jie +1 位作者 CHEN Zhongpei REN Wei 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第6期839-847,共9页
In recent years,growth hormone and insulin-like growth factors have become key regulators of bone metabolism and remodeling,crucial for maintaining healthy bone mass throughout life.Studies have shown that adult growt... In recent years,growth hormone and insulin-like growth factors have become key regulators of bone metabolism and remodeling,crucial for maintaining healthy bone mass throughout life.Studies have shown that adult growth hormone deficiency leads to alterations in bone remodeling,significantly affecting bone microarchitecture and increasing fracture risk.Although recombinant human growth hormone replacement therapy can mitigate these adverse effects,improving bone density,and reduce fracture risk,its effectiveness in treating osteoporosis,especially in adults with established growth hormone deficiency,seems limited.Bisphosphonates inhibit bone resorption by targeting farnesyl pyrophosphate synthase in osteoclasts,and clinical trials have confirmed their efficacy in improving osteoporosis.Therefore,for adult growth hormone deficiency patients with osteoporosis,the use of bisphosphonates alongside growth hormone replacement therapy is recommended. 展开更多
关键词 growth hormone adult growth hormone deficiency OSTEOPOROSIS BISPHOSPHONATES insulin-like growth factor 1 SKELETON
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“三双”会计人才培养模式的探索 被引量:17
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作者 孔德兰 李华 +4 位作者 张惠君 姚军胜 邵月花 杨艾 于玲燕 《中国职业技术教育》 北大核心 2015年第2期63-67,共5页
为了有效破解会计专业人才普适性与特色化培养、通用性与行业个性化需求相结合、充分发挥学校的优势与特色等问题,浙江金融职业学院会计专业基于学院金融行业背景与优势,提出并构建了"双素、双能、双证"的"三双"高... 为了有效破解会计专业人才普适性与特色化培养、通用性与行业个性化需求相结合、充分发挥学校的优势与特色等问题,浙江金融职业学院会计专业基于学院金融行业背景与优势,提出并构建了"双素、双能、双证"的"三双"高素质技能型会计人才培养模式。本文在介绍"三双"高素质技能型会计人才培养模式的实施背景基础上,提出了"三双"高素质技能型会计人才培养的基本思路和主要举措,并阐述了"三双"高素质技能型会计人才培养的理论价值和实践成效。 展开更多
关键词 会计专业 双素 双能 双证 实践
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Grain Crop Fertilization Status and Factors Influencing Farmers' Decision Making on Fertilizer Use: China Case Study 被引量:5
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作者 闫湘 金继运 梁鸣早 《Agricultural Science & Technology》 CAS 2016年第10期2394-2398,2440,共6页
[Objective] China is the world's largest fertilizer consumer. Fertilizer plays an important role in maintaining China's food security. Along with population and economic growth, overuse of fertilizers has caused ser... [Objective] China is the world's largest fertilizer consumer. Fertilizer plays an important role in maintaining China's food security. Along with population and economic growth, overuse of fertilizers has caused serious environmental problems, such as soil acidification, decline in soil organic carbon, and agricultural non-point source pollution. This study aimed to analyze the factors influencing farmers" decision making on fertilizer use, and provide policy recommendations on ways to affect fertilization. [Method] An econometric model reflecting fertilization of rural households was estimated from a survey distributed to 1 043 households randomly selected from 19 provinces in China. [Result] Results of the study showed that education years of fertilizer decision maker, fertilizer quality, organic fertilizer application, fertilizer price, and agricultural product price had significant effects on the fertilizer application rate at 1% level. Soil nutrient affected the fertilizer application rate at 10% level. [Conclusion] Policies aimed at improving the reasonable use of fertilizer should focus on the regulation of chemical fertilizer price, foundation of the organic-inorganic fertilizer system, soil testing, formulated fertilization, and agricultural extension service. 展开更多
关键词 FARMERS Fertilizer application rate Influencing factors Double logarith- mic model
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Research on the Lectin in Muscle Tissue of Varicorhinus macrolepis 被引量:4
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作者 庞秋香 赵先锋 +2 位作者 孙欢欢 赵博生 孙皓 《Agricultural Science & Technology》 CAS 2011年第10期1535-1538,共4页
[Objective] The paper aimed at researching lectins in muscles of Varicorhinus macrolepis and providing scientific basis for researching the adaptation mechanism and immune response of V.macrolepis to environment,which... [Objective] The paper aimed at researching lectins in muscles of Varicorhinus macrolepis and providing scientific basis for researching the adaptation mechanism and immune response of V.macrolepis to environment,which were advantageous for the protection and reproduction of V.macrolepis.[Method] V.macrolepis was used as test materials for the hemagglutination test by dialdehyde fixation to prove the existence of lectins in muscle crude homogenate of Varicorhinus macrolepis and study the physical and chemical characters.[Result] Lectins in muscle crude homogenate of V.macrolepis had shown hemagglutination effects on erythrocytes of six types of animals and had the maximum hemagglutination activity against rabbit erythrocytes,which belonged to the S-type lectins with optimal pH ranged from 4 to 8 and optimal temperature at 60 ℃.Results from the saccharide inhibition test had indicated that the sucrose was the only kind of saccharide which had inhibited the hemagglutination,suggesting that sucrose had played an important role in the process of recognition and aggregation of lectins.[Conclusion] It had been speculated that the optimal pH ranges for thermal sensitivity and hemagglutination activity of lectins in different types of aquatic organisms were similar. 展开更多
关键词 V.macrolepis Muscle crude homogenate LECTIN Dialdehyde fixation Hemagglutination activity
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Effect of Catalyst Properties on Hydrocracking of Pyrolytic Lignin to Liquid Fuel in Supercritical Ethanol 被引量:1
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作者 姚倩 唐喆 +2 位作者 郭建华 张颖 郭庆祥 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期209-216,I0002,共9页
The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore si... The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore size and supported metal on hydrocracking of pyrolytic lignin in supercritical ethanol and hydrogen were investigated at 260 ℃. A series of catalysts were prepared and characterized by BET, XRD, and NHa-TPD techniques. The results showed that enhancing the acidity of the catalyst without metal can promote pyrolytic lignin poly- merization to form more solid and condensation to produce more water. The pore size of microporous catalyst was smaller than mesoporous catalyst. Together with strong acid- ity, it caused pyrolytic lignin further hydrocrack to numerous gas. Introducing Ru into acidic catalysts promoted pyrolytic lignin hydrocracking and inhibited the polymerization and condensation, which caused the yield of pyrolytic lignin liquefaction product to increase significantly. Therefore, bifunctional catalyst with high hydrocracking activity metal Ru supported on materials with acidic sites and mesopores was imperative to get satisfactory results for the conversion of pyrolytic lignin to liquid products under supercritical conditions and hydrogen atmosphere. 展开更多
关键词 Pyrolytic lignin HYDROCRACKING Bifunctional catalyst
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Optimization of dual electrolyte and characteristic of micro-arc oxidation coating fabricated on ZK60 Mg alloy 被引量:5
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作者 芦笙 王泽鑫 +1 位作者 陈静 周小淞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期929-935,共7页
Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The ... Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO 2 and Na 3 PO 4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The microstructural characteristics of coatings were investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). Test of mass loss was conducted at a 3.5% NaCl solution to assess the resistance to corrosion. The effect of every element in the dual electrolyte system on voltage—time responses during MAO process and the coating characteristic were also analyzed and discussed systematically via single factor experiments. The results reveal that the main components of NaAlO 2 and Na 3 PO 4 as well as additives of NaOH, NaB4O7 and C6H5Na3O7 demonstrate different effects on MAO process and coating characteristics. By means of single factor experiments, an optimized dual electrolyte system was developed, containing 17.5 g/L NaAlO 2, 5.0 g/LNa3 PO4, 5.0 g/L NaOH, 3.0 g/L NaB4O7 and 4.2g/LC6H5Na3O7 . 展开更多
关键词 magnesium alloy micro-arc oxidation dual electrolyte OPTIMIZATION single factor experiment
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Effects of Silicon Levels on Rice Grain Yield and Its Nitrogen Absorption
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作者 吴建富 姚仲生 +3 位作者 谢凡 付桃秀 石庆华 潘晓华 《Agricultural Science & Technology》 CAS 2016年第8期1892-1895,共4页
Pot experiments were conducted to investigate the influence of Si fertilizer on yield and N-uptake and use efficiency of double-season rice under the conditions of equal nitrogen, phosphorus and potassium nutrients. T... Pot experiments were conducted to investigate the influence of Si fertilizer on yield and N-uptake and use efficiency of double-season rice under the conditions of equal nitrogen, phosphorus and potassium nutrients. The results showed that along with the increase of Si fertilizer application, the yield of early and late rice increased firstly and then decreased within the range of SiO2 application rate of 0-0.8 g/kg soil. There was a significant parabolic correlation between the amounts of Si fertilizer application and rice grain yield (r= 0.931 2 and r= 0.973 3 in early-and late-rice season, respectively). Results showed that efficient Si fertilizer application enchanced N contents in different plant components of early rice at maturity stages with increased nitrogen uptake of double cropping rice and nitrogen harvest index of late rice. 展开更多
关键词 Silicon fertilizer Double cropping rice YIELD N utilization
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Isolation of Plasma and Thylakoid Membranes from the Heterocystous Cyanobacterium Anabaena sp. PCC 7120
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作者 李斌 徐冬一 赵进东 《Acta Botanica Sinica》 CSCD 2001年第6期650-652,共3页
利用水溶性多聚体双相法分离蓝细菌Anabaenasp .PCC 712 0质膜和类囊体膜两种膜系统。吸收光谱分析表明 ,质膜相和类囊体膜相的主要色素分别为类胡萝卜素和叶绿素。SDS_凝胶电泳显示这两种膜系统蛋白组成有很大差别。这种分离方法容易操... 利用水溶性多聚体双相法分离蓝细菌Anabaenasp .PCC 712 0质膜和类囊体膜两种膜系统。吸收光谱分析表明 ,质膜相和类囊体膜相的主要色素分别为类胡萝卜素和叶绿素。SDS_凝胶电泳显示这两种膜系统蛋白组成有很大差别。这种分离方法容易操作 ,对研究蓝细菌的膜蛋白和膜脂非常有用。 展开更多
关键词 CYANOBACTERIUM plasma and thylakoid membranes isolation and purification two_phase partition
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Desmosflavanone Ⅱ: A New Flavanone from Desmos cochinchinensis Lour 被引量:1
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作者 吴久鸿 廖时萱 +3 位作者 毛士龙 梁华清 王彦来 苏中武 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第3期7-9,共3页
A new flavanone was isolated from the roots of Desmos cochinchinensis Lour Its chemical structure was elucidated by spectral analysis as 7 hydroxy 5 methoxy 8 formyl 6 methylflavanone, named desmosflavanone Ⅱ
关键词 Amonaceae Desmos cochinchinensis Lour FLAVANONE DesmosflavanoneⅡ
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A novel closed-loop vacuum silicon microgyroscope
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作者 夏敦柱 王寿荣 周百令 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期63-67,共5页
A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reach... A novel closed-loop control strategy of a silicon microgyroscope (SMG) is proposed. The SMG is sealed in metal can package in drive and sense modes and works under the air pressure of 10 Pa. Its quality factor reaches greater than l0 000. Self-oscillating and closed-loop methods based on electrostatic force feedback are adopted in both measure and control circuits. Both single side driving and sensing methods are used to simplify the drive circuit. These dual channel decomposition and reconstruction closed loops are applied in sense modes. The testing results demonstrate that useful signals and guadrature signals do not interact with each other because of the decoupling of their phases. Under the condition of a scale factor of 9. 6 mV/((°) .s), in a full measurement range of±300 (°)/s, the zero bias stability reaches 28 (°)/h with a nonlinear coefficient of 400 × 10^-6 and a simulated bandwidth of more than 100 Hz. The overall performance is improved by two orders of magnitude in comparison to that at atmospheric pressure. 展开更多
关键词 silicon micro-gyroscope (SMG) self oscillating dual-channel closed-loop detection scale factor zero bias stability
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Bi-modal microstructure in a powder metallurgical ferritic steel
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作者 刘锋 刘咏 +4 位作者 吴宏 方京华 赵大鹏 张刘杰 刘东华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期330-334,共5页
Ferritic steel with a nominal composition of Fe-14Cr-3W-0.42Ti-0.32Y was prepared by mixing gas-atomized prealloyed powder and mechanically alloyed powder. The microstructure is much different fxom other ferritic stee... Ferritic steel with a nominal composition of Fe-14Cr-3W-0.42Ti-0.32Y was prepared by mixing gas-atomized prealloyed powder and mechanically alloyed powder. The microstructure is much different fxom other ferritic steels with the same composition and prepared via only mechanically alloyed powder. A bi-modal structure, which consists of pure ferritic grains and martensitic grains, was obtained after hot forging and air cooling. A phase transformation of αbcc→γfcc→α'bcc was also discovered in microstructural observation. The bi-modal microstructure shows a good combination of high strength and high ductility. 展开更多
关键词 ferritic steel powder metallurgy phase transformation bi-modal microstructure mechanical property
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Metabolites of baicalein 6,7-diacetate in rats 被引量:1
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作者 胡芸 郭晓宇 +1 位作者 杨琳 车庆明 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第4期309-313,共5页
To investigate the metabolites of baicalein 6,7-diacetate in rats. HPLC-DAD and LC/MS^n methods were used to analyze the metabolites in intestinal tract and plasma after oral administration of baicalein 6,7-diacetate ... To investigate the metabolites of baicalein 6,7-diacetate in rats. HPLC-DAD and LC/MS^n methods were used to analyze the metabolites in intestinal tract and plasma after oral administration of baicalein 6,7-diacetate to rats. Baicalein 6,7-diacetate was degraded into baicalein 6-monoacetate and baicalein in rat intestinal tract, and four baicalein glucuronides, baicalein 6-0- glucuronide, baicalein 6-methoxyl-7-O-glucuronide, baicalein 6,7-di-O-glucuronide, and baicalein 6-O-glucose-7-O-glucuronide were detected and tentatively identified in rat plasma. This is the first time to report the metabolites of baicalein 6,7-diacetate in rats. Six metabolites were identified in rat intestinal tract and plasma. 展开更多
关键词 Baicalein 6 7-diacetate BAICALEIN METABOLITES
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Anti-inflammatory activity of probiotic Bifidobacterium: Enhancement of IL-10 production in peripheral blood mononuclear cells from ulcerative colitis patients and inhibition of IL-8 secretion in HT-29 cells 被引量:38
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作者 Akemi Imaoka Tatsuichiro Shima +6 位作者 Kimitoshi Kato Shigeaki Mizuno Toshiki Uehara Satoshi Matsumoto Hiromi Setoyama Taeko Hara Yoshinori Umesaki 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第16期2511-2516,共6页
AIM: To determine the anti-inflammatory activity of probiotic Bifidobacteria in Bifidobacteria-fermented milk (BFM) which is effective against active ulcerative colitis (UC) and exacerbations of UC, and to explore the... AIM: To determine the anti-inflammatory activity of probiotic Bifidobacteria in Bifidobacteria-fermented milk (BFM) which is effective against active ulcerative colitis (UC) and exacerbations of UC, and to explore the immunoregulatory mechanisms. METHODS: Peripheral blood mononuclear cells (PBMNC) from UC patients or HT-29 cells were co-cultured with heat-killed probiotic bacteria or culture supernatant of Bifidobacterium breve strain Yakult (BbrY) or Bifidobacterium bifidum strain Yakult (BbiY) to estimate the amount of IL-10 or IL-8 secreted. RESULTS: Both strains of probiotic Bifidobacteria contained in the BFM induced IL-10 production in PBMNC from UC patients, though BbrY was more effective than BbiY. Conditioned medium (CM) and DNA of both strains inhibited IL-8 secretion in HT-29 cells stimulated with TNF-α, whereas no such effect was observed with heat- killed bacteria. The inhibitory effect of CM derived from BbiY was greater than that of CM derived from BbrY. DNAs of the two strains had a comparable inhibitory activity against the secretion of IL-8. CM of BbiY induced a repression of IL-8 gene expression with a higher expression of IκB-ζ mRNA 4 h after culture of HT-29 cells compared to that in the absence of CM.CONCLUSION: Probiotic Bifidobacterium strains in BFM enhance IL-10 production in PBMNC and inhibit IL-8 secretion in intestinal epithelial cells, suggesting that BFM has anti-inflammatory effects against ulcerative colitis. 展开更多
关键词 BIFIDOBACTERIUM Ulcerative colitis ANTI-INFLAMMATORY Intedeukin-10 INTERLEUKIN-8
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Comparison of Meiofaunal Abundance in Two Mangrove Wetlands in Tong'an Bay, Xiamen, China 被引量:5
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作者 ZHOU Xiping CAI Lizhe FU Sujing 《Journal of Ocean University of China》 SCIE CAS 2015年第5期816-822,共7页
To compare meiofaunal community in the two mangrove wetlands in Tong'an Bay, Xiamen, China, and probe the response of meiofauna to high organic matter, sampling was carried out in Fenglin and Xiang'an mangrove wetla... To compare meiofaunal community in the two mangrove wetlands in Tong'an Bay, Xiamen, China, and probe the response of meiofauna to high organic matter, sampling was carried out in Fenglin and Xiang'an mangrove wetlands in the bay. The results showed that the Ne/Co ratio (nematode to benthic copepod) and organic matter in Fenglin mangrove wetland were higher than those in Xiang'an mangrove wetland. The meiofaunal abundance in Fenglin mangrove was all lower than that in Xiang'an mangrove wetland in summer, autumn and spring, while the meiofaunal abundance in Fenglin mangrove was higher than that in Xiang'an mangrove wetland in winter. Two-way ANOVA results showed that the meiofaunal abundance and nematode abundance were significantly different between regions, seasons and regionxseason. With all the results in the present study, we confirmed that the positive response of meiofaunal and nematode abundance were only detected for medium organic matter contents according to the Xiang'an wetland's level, and that the distribution of meiofaunal abundance would be influenced by sand content. Higher copepod abundance and lower N/C value usually suggest better environmental quality. 展开更多
关键词 MEIOFAUNA nematodes COPEPODS mangrove wetland Tong'an Bay
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Different Treatment Methods on Seed Germination Seedlings 被引量:1
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作者 Zhihua WU Jiping NIU 《Agricultural Science & Technology》 CAS 2017年第10期1882-1886,1891,共6页
[Objective] This study was conducted to investigate the effects of different gibberellic acid and hydrogen peroxide concentrations and different soaking time on the germination potential and germination rate of Scutel... [Objective] This study was conducted to investigate the effects of different gibberellic acid and hydrogen peroxide concentrations and different soaking time on the germination potential and germination rate of Scutellaria baicalensis, so as to improve the breeding efficiency of S. baicalensis. [Method] Dry seeds were divided into 3 groups, each containing 50 grains, which were weighed and put in a culture dish and soaked with distilled water covering the surface of seeds at room temperature. The seed weight was measured by gravimetric method once every 30 min from 30 rain after soaking, until the weight of the seeds no longer changed. [Result] With the increase of the concentration of hydrogen peroxide, the germination rate of S. baicalensis was improved gradually, and reached 32.0% under the concentration of 1.0% at the soaking time of 24 h; and with the increase of the concentration of gibberellic acid, the germination rate of S. baicalensis was improved gradually, and reached 64.0% under the concentration of 600 mg/L at the soaking time of 24 h. [Conclusion] The constant temperature at 25 ℃ in the incubator could also improve the seed germination rate; and the germination rate achieved by treating the seeds with gibbereUic acid was remarkably higher than that achieved by treating the seeds with hydrogen peroxide. 展开更多
关键词 Scutellaria baicalensis Gibberellic acid Hydrogen peroxide Soaking time
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QTLs for Rice Leaf Chlorophyll Content Under Low N Stress 被引量:9
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作者 FANGPing YUXiao-Min +1 位作者 ZHURi-Qing WUPing 《Pedosphere》 SCIE CAS CSCD 2004年第2期145-150,共6页
Quantitative trait loci (QTLs) for chlorophyll content of a rice leaf weremapped on to the molecular marker linkage map of a double-haploid (DH) population derived from across between two rice varieties 'IR64'... Quantitative trait loci (QTLs) for chlorophyll content of a rice leaf weremapped on to the molecular marker linkage map of a double-haploid (DH) population derived from across between two rice varieties 'IR64' and 'Azucena' in both nutrient solutionand soil cultureexperiments to detect rice nitrogen nutrition status under low N stress A chlorophyll meter was usedto measure the soil plant analysis development (SPAD) value of the topmost fully expanded leaf asthe index of chlorophyll content thatexpressed nitrogen status in rice plants. Totally 3 QTLs forSPAD values, two on chromosome 3 located at interval RG179-CDO337 and RG348-RZ329, respectively, andone on chromosome 10 at interval RZ500-RG134, were detected under stressed conditions of low N inthe soil and/or nutrient solution culture experiments. One QTL located at interval RG179-GDO337 onchromosome 3 associated with a relative change in SPAD value from a high N level to a low N level inthe soil culture experiment was also detected.Based on the different responses to low N stressbetween the two parents, it was supposed that the QTLs identified in this study associated withnitrogen efficiency in rice at low N levels might be useful in applying marker technology to ricebreeding programs. 展开更多
关键词 chlorophyll meter nitrogen efficiency QTLS rice (Oryza sativa L.) SPADvalue
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Determination of astaxanthin and astaxanthin esters in shrimp shell by HPLC 被引量:8
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作者 LI Shuai GUO Jun-ru +6 位作者 FENG Jin-hua ZHU Ze-min LI Ling-li GUO Xiao-fang SUI Wen-yan WANG Meng ZUO Wen-ting 《Marine Science Bulletin》 CAS 2019年第2期57-71,共15页
A method for determination of astaxanthin and astaxanthin eaters in shrimp shell by high performance liquid chromatography is established.Shrimp shell are addressed with 5%hydrochloric acid to remove calcium ions.Afte... A method for determination of astaxanthin and astaxanthin eaters in shrimp shell by high performance liquid chromatography is established.Shrimp shell are addressed with 5%hydrochloric acid to remove calcium ions.After shell is dried,organics from shrimp shell are extracted with anhydrous ethanol.The alcohol extrative of the shrimp shell is mixed with the ammonium sulfate to extract astaxanthin by aqueous two-phase extraction.The crude astaxanthin is collected,which is distributed in the middle layer of the aqueous two-phase layer.After distilled water is added to the crude astaxanthin,the aqueous solution is centrifuged,and the previous step is repeated for several times.The precipitation in centrifuge tube is collected and dried.The crude astaxanthin dried is dissolved with acetone,and the sample solution is separated by TLC.Every pigment on the TLC plate is collected and dissolved with acetone.The pigments are determined by high performance liquid chromatograph.The results show that aqueous two-phase system,3 mL alcohol extractive of astaxanthin and 4.5 mL 20%ammonium sulfate,can be used to acquire crude astaxanthin.The wavelength of the maximum peak of astaxanthin in ethanol solution is 472 nm.A variety of pigments can be separated from the crude astaxanthin by thin-layer chromatography,including free astaxanthin,astaxanthin monoester,astaxanthin diester,echinenone and other substances.It can be seen from high performance liquid chromatography that the appearance time of free astaxanthin is from 4 min to 5.5 min,and the appearance time of astaxanthin monoester is from 10.5 min to 27.8 min.The method is simple about the sample pretreatment and feasible about the determination of astaxanthin and astaxanthin esters in shrimp shell. 展开更多
关键词 ASTAXANTHIN astaxanthin esters aqueous two-phase thin-layer chromatography high performance liquid chromatography
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Safety assessment of Bifidobacterium longum JDM301 based on complete genome sequences 被引量:5
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作者 Yan-Xia Wei Zhuo-Yang Zhang +2 位作者 Chang Liu Pradeep K Malakar Xiao-Kui Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第5期479-488,共10页
AIM: To assess the safety of Bifidobacterium/ongum (B. longum) JDM301 based on complete genome sequences. METHODS: The complete genome sequences of JDM301 were determined using the GS 20 system. Putative virulence... AIM: To assess the safety of Bifidobacterium/ongum (B. longum) JDM301 based on complete genome sequences. METHODS: The complete genome sequences of JDM301 were determined using the GS 20 system. Putative virulence factors, putative antibiotic resis- tance genes and genes encoding enzymes respon- sible for harmful metabolites were identified by blast with virulence factors database, antibiotic resistance genes database and genes associated with harmful metabolites in previous reports. Minimum inhibitory concentration of 16 common antimicrobial agents was evaluated by E-test RESULTS: JDM301 was shown to contain 36 genes as- sociated with antibiotic resistance, 5 enzymes related to harmful metabolites and 162 nonspecific virulence fac- tors mainly associated with transcriptional regulation, adhesion, sugar and amino acid transport. B. longum JDM301 was intrinsically resistant to ciprofloxacin, ami- kacin, gentamicin and streptomycin and susceptible to vancomycin, amoxicillin, cephalothin, chloramphenicol, erythromycin, ampicillin, cefotaxime, rifampicin, imi- penem and trimethoprim-sulphamethoxazol. JDM301 was moderately resistant to bacitracin, while an earlier study showed that bifidobacteria were susceptible to this antibiotic. A tetracycline resistance gene with the risk of transfer was found in JDM301, which needs to be experimentally validated. CONCLUSION: The safety assessment of JDM301 using information derived from complete bacterial ge- nome will contribute to a wider and deeper insight into the safety of probiotic bacteria. 展开更多
关键词 Bifidobacterium longum Safety assess-ment GENOME Antibiotic resistance Harmful metabo-lite Virulence factor
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