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Feeding Effect of Triticale Fodder as Replacement of Straw on Production Performance of Dairy Cows 被引量:2
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作者 Nathu Ram Sarker Mohammad Asaduzzaman +4 位作者 Khan Shahidul Huque Mohammad Toyebur Rahman NazrulIslam Mohammad Enamul Haque Stephen R. Waadington 《Journal of Agricultural Science and Technology(A)》 2013年第1期72-82,共11页
关键词 生产性能 小黑麦 奶牛场 粗饲料 秸秆 饲喂效果 干物质采食量 饮食治疗
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Effects of Supplementing Various Linoleic to α-linolenic Acid Ratios and Vitamin A on Production Performance and Egg Characteristics of Laying Hens during Summer Months 被引量:1
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作者 S.Ahmad M.Yousaf +5 位作者 Z.Kamran M.U.Sohail M.N.Tahir K.C.Koutoulis A.Manzoor 《Journal of Zoological Research》 2019年第1期1-9,共9页
In the present feeding trial,responses of laying hens that were kept at high ambient temperature and Fed with various dietary ratios of linoleic acid(LNA)toα-linolenic acid(ALA)and vitamin A levels on production perf... In the present feeding trial,responses of laying hens that were kept at high ambient temperature and Fed with various dietary ratios of linoleic acid(LNA)toα-linolenic acid(ALA)and vitamin A levels on production performance and egg quality traits were evaluated.A total of 360 Leghorn laying hens at 40th week of age(average initial body weight;1.79±0.23 kg)were fed with various combinations of canola oil and linseed oil containing diets to achieve LNA to ALA dietary ratios of 20:1,10:1,4:1,2:1,1:1 and 1:2,each supplemented with 3000 or 10000 IU of vitamin A/kg of diet.The experiment was designed as a 6×2 factorial Completely Randomized Design that continued for 12 weeks.Feed intake,body weight gain,egg production and egg quality traits were recorded during the trial.Decreasing dietary LNA to ALA ratio or increasing poly unsaturated fatty acids(PUFA)in the diet decreased(P<0.05)body weight gain and yolk percentage in laying hens.Feed intake,hen-day and hen-housed egg production,feed conversion ratio(FCR)per dozen of eggs and shell quality remained unaffected(P>0.05)by dietary treatments.Feed conversion ratio per kg eggs,egg weight and egg-shell thickness showed a curvilinear(P<0.05)response to decreasing dietary LNA to ALA ratio.Although the dietary ratio of LNA to ALA of 4:1 or less could produce eggs by the hens with desirable quantities of n-6 and n-3 PUFA–that are characteristics of functional diets–the performance of laying hens in terms of body weight gain and egg-yolk percentage was slightly compromised.Therefore,a 4:1 or 2:1 LNA to ALA combination can make a borderline between the production traits and the feed economics. 展开更多
关键词 EGG quality FATTY ACIDS Hot climate Layers performance VITAMIN A
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Study on Feeding Effect of Different Levels of Protein and Energy on Production Performance of Pregnant Mother and Neo-Natal Calves
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作者 Nathu Ram Sarker Muhammad Khaiml Bashar Sheik Mohammad Jahangir Hossain Mohammed Khorshed Alam and Khan Shahidul Huque 《Journal of Agricultural Science and Technology(A)》 2015年第2期81-89,共9页
关键词 蛋白质需要 能量水平 妊娠期 牛犊 性能影响 生产 饮食治疗 出生体重
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不同上部刚度对木框架剪力墙受力性能影响的试验研究 被引量:13
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作者 刘雁 Ni Chun +2 位作者 卢文胜 吕西林 周定国 《土木工程学报》 EI CSCD 北大核心 2008年第11期63-70,共8页
木框架剪力墙试验研究时,荷载传递梁的刚度对木框架剪力墙的破坏模式以及侧向荷载承载力有直接的影响,当木框架剪力墙墙端以及墙中洞口边未采用墙端锚栓时,这种影响更甚。当墙顶连接铰接荷载传递梁时,在水平荷载作用下,木框架剪力墙的... 木框架剪力墙试验研究时,荷载传递梁的刚度对木框架剪力墙的破坏模式以及侧向荷载承载力有直接的影响,当木框架剪力墙墙端以及墙中洞口边未采用墙端锚栓时,这种影响更甚。当墙顶连接铰接荷载传递梁时,在水平荷载作用下,木框架剪力墙的墙端易于被上拔而与墙基础分离,此时试验所得到的木框架剪力墙的侧向荷载承载力接近于下限值;反之,刚性荷载传递梁所得到的木框架剪力墙的侧向荷载承载力接近于上限值。主要通过22片墙体的试验研究来了解上层墙体、楼盖刚度对下层木框架剪力墙受力性能的影响。其中16片为6m长2.44m高的单层足尺木框架剪力墙,墙顶一半采用铰接荷载传递梁一半采用刚性荷载传递梁,4片为足尺典型二层墙体,另外2片为增加了墙端锚栓的单层足尺木框架剪力墙。对试验结果从初始刚度、极限荷载、极限位移、能量耗散以及锚栓内力等方面进行分析,最后形成了采用刚性荷载传递梁和二层墙体均能增加墙体侧向荷载承载力的结论。 展开更多
关键词 木框架剪力墙 受力性能 刚度
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利用染色体步移PCR检测辐射松的单核苷酸多态性 被引量:4
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作者 李伟 李慧 +1 位作者 陈晓阳 WU Harry 《西北植物学报》 CAS CSCD 北大核心 2007年第8期1571-1576,共6页
用染色体步移技术(chromosome walking)的基本原理以辐射松(Pinus radiata)肌动蛋白基因(actin)为例,利用获得的EST序列设计定向引物,向上游和下游进行了染色体序列的步移.获得了包括启动子、5′端非编码区和编码区及3′端非编码区辐射... 用染色体步移技术(chromosome walking)的基本原理以辐射松(Pinus radiata)肌动蛋白基因(actin)为例,利用获得的EST序列设计定向引物,向上游和下游进行了染色体序列的步移.获得了包括启动子、5′端非编码区和编码区及3′端非编码区辐射松肌动蛋白基因基因组序列2154 bp.通过对200株不同辐射松个体进行PCR扩增及测序,共获得了21个SNPs,其中启动子区域3个,编码区15个,3′端非编码区4个.实验结果为今后染色体步移技术在基因非编码区SNP的检测提供了理论与技术参考. 展开更多
关键词 染色体步移 PCR 辐射松 单核苷酸多态性
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功率因数校正的数字控制技术应用研究 被引量:8
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作者 陈新 Charlie Wu W Hutchings 《南京航空航天大学学报》 EI CAS CSCD 北大核心 2007年第2期164-170,共7页
以单管Boost型PFC电路作为研究对象,分别针对电流断续、电流临界连续和电流连续3种工作模态,详细讨论了数字控制PFC的实现方法和设计过程,并分别给出了样机实验结果;此外,结合M C 56F 8013的外设资源特点,给出了基于DSP的PFC详细的系统... 以单管Boost型PFC电路作为研究对象,分别针对电流断续、电流临界连续和电流连续3种工作模态,详细讨论了数字控制PFC的实现方法和设计过程,并分别给出了样机实验结果;此外,结合M C 56F 8013的外设资源特点,给出了基于DSP的PFC详细的系统接口设计,包括PWM控制策略和同步控制AD采样环节。对PFC的数字控制方案进行了系统研究,提供了不同工作模式下的完整数字控制解决方案,为功率因数的数字控制技术应用提供了较好的参考作用。 展开更多
关键词 数字信号处理 功率因数校正 数字控制 PI控制
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基于DSC控制的移相全桥DC/DC变换器 被引量:6
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作者 陈新 Charlie WU WHut chings 《电力电子技术》 CSCD 北大核心 2006年第5期38-41,共4页
数字控制由于高集成度带来的低成本、设计沿继性、控制灵活等优点而应用逐渐广泛,电力电子应用逐渐朝着高频化方向发展,这也对高频开关电源的数字控制提出了要求。利用Freescale新型号数字信号控制器(DigitalSingnalController,DSC)MC56... 数字控制由于高集成度带来的低成本、设计沿继性、控制灵活等优点而应用逐渐广泛,电力电子应用逐渐朝着高频化方向发展,这也对高频开关电源的数字控制提出了要求。利用Freescale新型号数字信号控制器(DigitalSingnalController,DSC)MC56F8323的高性能特性,完成了基于DSC的带同步整流的高频软开关移相全桥变换器的数字控制,描述了DSC产生软件移相控制策略,并给出了详细的数字控制系统设计和软件结构设计,最后用一台500W实验样机验证了数字控制所带来的优良的系统性能。 展开更多
关键词 变换器 移相全桥 数字控制/数字信号控制器 数字信号处理器
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DROLOXIFENE枸橼酸盐的工艺改进及其新的生物活性
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作者 陈瑛 夏鹏 +3 位作者 张倩 郑云红 夏奕 杨征宇 《药学学报》 CAS CSCD 北大核心 2000年第12期902-905,共4页
目的 探索droloxifene的合成方法 ,并对其新的生物活性进行研究。方法和结果 以甲氧基苯和苯乙酸为原料 ,经酰氯化、付 克反应、烷基化、去甲基化、醚化、格氏加成、消除脱水、构型转化及成盐共 9步反应 ,得droloxifene枸橼酸盐 ,8... 目的 探索droloxifene的合成方法 ,并对其新的生物活性进行研究。方法和结果 以甲氧基苯和苯乙酸为原料 ,经酰氯化、付 克反应、烷基化、去甲基化、醚化、格氏加成、消除脱水、构型转化及成盐共 9步反应 ,得droloxifene枸橼酸盐 ,8步收率 14 7% (9 2 % [1] )。生物活性实验发现其具有缓解肿瘤细胞多药耐药性和诱导黄体细胞凋亡的两种新的生物活性。结论 本文对droloxifene的合成工艺进行了改进 ,反应步骤缩短两步 ,异构体分离、转化方法简便 ,原料及试剂易得 ,操作简便。两种新的生物活性的发现对新药研究及扩大临床应用提供了实验依据。 展开更多
关键词 DROLOXIFENE 枸橼酸盐 抗癌药 生物活性
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SPAM模型和遥感结合提取华北地区春夏玉米种植面积 被引量:7
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作者 陈卓 谢苗苗 +6 位作者 范玲玲 陈浩 梁社芳 李正国 游良志 吴文斌 杨鹏 《中国农业资源与区划》 CSCD 北大核心 2018年第8期124-134,共11页
[目的]获取农作物空间分布信息,对于研究区域粮食安全、气候变化、陆地碳氮循环和水资源利用等都具有重要意义。[方法]该研究首先应用作物空间分配模型(SPAM-China模型),在5'×5'栅格尺度上重建了1980—2010年华北地区玉米... [目的]获取农作物空间分布信息,对于研究区域粮食安全、气候变化、陆地碳氮循环和水资源利用等都具有重要意义。[方法]该研究首先应用作物空间分配模型(SPAM-China模型),在5'×5'栅格尺度上重建了1980—2010年华北地区玉米空间分布信息;然后基于SPOT VEGETATION长时间序列NDVI数据,获取了该区域的作物熟制信息,并进一步划分出了华北地区春、夏玉米种植类型区;最后,重点分析了2000—2010年间华北地区春玉米和夏玉米种植区域的时空变化特征。[结果](1)1980—2010期间,华北地区玉米种植面积增加了360万hm2,增加面积集中在中南部地区,变化主要发生在2000年以后;(2)2000—2010期间,华北地区春玉米面积增加136万hm2,占该区玉米总种植面积的比例由17%上升至27%;夏玉米种植面积尽管也增加了87万hm2,但占该区玉米总种植面积的比重呈下降趋势;(3)春夏玉米混种区为华北地区玉米主产区,近年来呈现为春玉米增加、夏玉米减少的发展趋势,全区域92%春玉米面积增加和76%夏玉米面积减少均发生在春夏玉米混种区域内,可见该区以春玉米为代表的一熟制正呈现逐步取代以冬小麦—夏玉米为主二熟制的变化趋势。[结论]该文基于SPAM模型和遥感结合提取华北地区春、夏玉米种植面积的方法,为大区域、长时间尺度作物种植信息的获取提供了新思路。 展开更多
关键词 玉米 作物空间分配模型 种植制度 NDVI 华北地区
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Antioxidant activity and identification of bioactive compounds from leaves of Anthocephalus cadamba by ultra-performance liquid chromatography/electrospray ionization quadrupole time of flight mass spectrometry 被引量:6
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作者 Madhu Chandel Upendra Sharma +2 位作者 Neeraj Kumar Bikram Singh Satwinderjeet Kaur 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第12期977-985,共9页
Objective:To evaluate the antioxidant potential of different extract/fractions of Anthocephalus cadamba(A.cadamba)(Roxb.) Miq.(Rubiaceae) and study the tentative identification of their active constituents.Metho... Objective:To evaluate the antioxidant potential of different extract/fractions of Anthocephalus cadamba(A.cadamba)(Roxb.) Miq.(Rubiaceae) and study the tentative identification of their active constituents.Methods:The extract/fractions were screened for antioxidant activity using various in vitro assays viz.DPPH assay,ABTS assay,superoxide anion radical scavenging assay, reducing power assay and plasmid DNA nicking assay.Total phenolic content of extract/fractions was determined by colorimetric method.An ultra-performance LC-electrospray-quadrupoletime of flight mass spectrometry method was used to analyse the active constituents of extract/ fractions of A.cadamba.Results:The ethyl acetate fraction was found to be most active fraction in all the assays as compared to other extract/fractions.The IC<sub>50</sub> value of ethyl acetate fraction (ETAC fraction) was 21.24μg/mL,1.12μg/mL,9.68μg/mL and S7.81μg/mL in DPPH assay, ABTS assay,reducing power assay and superoxide scavenging assay respectively.All the extract/ fractions also showed the potential to protect the plasmid DNA(pBR322) against the attack of hydroxyl radicals generated by Fenton’s reagent.The bioactive compounds were identified by UPLC-ESI-QTOF-MS,by comparing the mass andλ<sub>max</sub> with literature values.Conclusions:The potential of the extract/fractions to scavenge different free radicals in different systems indicated that they may be useful therapeutic agents for treating radical-related pathologic damage. 展开更多
关键词 Anthocephalus cadamba ANTIOXIDANT ACTIVITY UPLC-ESI-QTOF-MS
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Experience on offshore cathodic protection retrofitting in the northern South China Sea 被引量:3
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作者 L. Patterson A. Amorelli +1 位作者 D. Condanni B. Bazzoni 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第4期679-688,共10页
Platforms I and II are steel structures located in offshore areas southeast of the Zhujiang (Pearl) River Delta, the northern South China Sea,. in about 110 in water depth. The jackets, with aluminum sacrificial anode... Platforms I and II are steel structures located in offshore areas southeast of the Zhujiang (Pearl) River Delta, the northern South China Sea,. in about 110 in water depth. The jackets, with aluminum sacrificial anodes for cathodic protection (CP) of the immersed zone, were launched in March 1995. In May 096 a CP survey showed that, after almost one year of service, a low polarization level had been achieved and some extended unprotected zones existed; mainly in the deepest part of the Platform II. Further to this, a joint activity was decided in order to assess the need of a possible retrofitting of the CP systems. The results of the activity carried out are dealt with, including technical and economical comparisons amongst several retrofitting options, both with sacrificial anodes and with impressed current systems. The adopted solution is illustrated and data are reported on the level of protection presently achieved. 展开更多
关键词 cathodic protection retrofitting OFFSHORE the South China Sea
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米糠油同时脱胶脱蜡物理精炼新技术 被引量:3
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作者 Rajam L Soban Kumar D R +2 位作者 Sundaresan A Arumughan C 武丽荣(译) 《中国油脂》 CAS CSCD 北大核心 2006年第7期27-32,共6页
对米糠油同时脱胶脱蜡物理精炼新工艺进行了小试研究,并在此基础上进行了生产试验。毛米糠油与氯化钙水溶液混合,在低温下结晶(20℃)使水化磷脂和非水化磷脂与蜡一起沉析分离,随后进行脱色和冬化(20℃)处理,进一步将磷脂含量降... 对米糠油同时脱胶脱蜡物理精炼新工艺进行了小试研究,并在此基础上进行了生产试验。毛米糠油与氯化钙水溶液混合,在低温下结晶(20℃)使水化磷脂和非水化磷脂与蜡一起沉析分离,随后进行脱色和冬化(20℃)处理,进一步将磷脂含量降到5mg/kg以下,再经物理精炼,即可使成品精炼米糠油满足市售商品对其色泽(10~12罗维朋值,25.4mm槽)、游离脂肪酸含量(〈0.25%)和浊点(4~5℃)的要求;且中性油损失少。米糠油含有多种生物活性物质,如谷维素,VE和甾醇。本工艺可在最终产品中保留80%以上的生物活性物质。 展开更多
关键词 氯化钙 物理精炼 米糠油 同时脱胶脱蜡
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化学处理法对竹材阻燃、抗菌和防腐的影响(英文) 被引量:2
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作者 SADHNA Tripathi 《林产化学与工业》 EI CAS CSCD 北大核心 2010年第4期7-14,共8页
研究了6种用于印度勒竹防护的制剂,主要用于阻燃、防火防腐、抗真菌和白蚁的腐蚀。考察了阻燃剂和新型环保防腐剂ZiBOC用于印度勒竹防护的协同作用。将裂开的竹片用质量分数为15%的6种防护组分处理,即按照印度标准方法测试火焰穿透性、... 研究了6种用于印度勒竹防护的制剂,主要用于阻燃、防火防腐、抗真菌和白蚁的腐蚀。考察了阻燃剂和新型环保防腐剂ZiBOC用于印度勒竹防护的协同作用。将裂开的竹片用质量分数为15%的6种防护组分处理,即按照印度标准方法测试火焰穿透性、可燃性和燃烧率。6种15%质量分数的组分分别为:1.硫酸铵+磷酸铵+ZiBOC;2.硫酸铵+ZiBOC;3.磷酸铵+ZiBOC;4.磷酸镁+焦硫酸镁+ZiBOC;5.磷酸镁+ZiBOC;6.焦磷酸镁+ZiBOC。结果表明,达到防护目的的不同化学组分的防护剂用量应为9~11.5kg/m3。用白腐菌的腐烂实验表明,配方为2、3、5和6的防护剂表现出较好的防腐作用(防护率达到95%,p〈0.05),而用褐腐菌其防护率约为43%~67%。采用经2~6配方处理过的样品均能抗第一、二期的白腐腐蚀,而第二期的白蚁对配方4处理过的样品有轻微的腐蚀作用。少数几种配方对材料的耐火性有提高。 展开更多
关键词 勒竹 阻燃剂 防腐剂 褐腐菌 白腐菌
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Lactogenic hormones alter cellular and extracellular microRNA expression in bovine mammary epithelial cell culture 被引量:5
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作者 Susumu Muroya Tatsuro Hagi +3 位作者 Ataru Kimura Hisashi Aso Masatoshi Matsuzaki Masaru Nomura 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2016年第4期504-513,共10页
Background: Bovine milk contains not only a variety of nutritional ingredients but also microRNAs (miRNAs) that are thought to be secreted by the bovine mammary epithelial cells (BMECs). The objective of this stu... Background: Bovine milk contains not only a variety of nutritional ingredients but also microRNAs (miRNAs) that are thought to be secreted by the bovine mammary epithelial cells (BMECs). The objective of this study was to elucidate the production of milk-related miRNAs in BMECs under the influence of lactogenic hormones. Results: According to a microarray result of milk exosomal miRNAs prior to cellular analyses, a total of 257 miRNAs were detected in a Holstein cow milk. Of these, 18 major miRNAs of interest in the milk were selected for an expression analysis in BMEC culture that was treated with or without dexamethasone, insulin, and prolactin (DIP) to induce a lactogenic differentiation. Quantitative polymerase chain reaction (qPCR) results showed that the expressions of miR-21-Sp (P = 0.005), miR-26a (P = 0.016), and miR-320a (P = 0.011) were lower in the DIP-treated cells than in the untreated cells. In contrast, the expression of miR-339a (P-- 0.017) in the cell culture medium were lower in the DiP-treated culture than in the untreated culture. Intriguingly, the miR-148a expression in cell culture medium was elevated by DIP treatment of BMEC culture (P = 0.018). The medium-to-cell expression ratios of miR- 103 (P = 0.025), miR-148a (P 〈 0.001), and miR-223 (P = 0.013) were elevated in the DIP-treated BMECs, suggesting that the lactogenic differentiation-induced secretion of these three miRNAs in BMECs. A bioinformatic analysis showed that the miRNAs down-regulated in the BMECs were associated with the suppression of genes related to transcriptional regulation, protein phosphorylation, and tube development. Conclusion: The results suggest that the miRNAs changed by lactogenic hormones are associated with milk protein synthesis, and mammary gland development and maturation. The elevated miR-148a level in DIP-treated BMECs may be associated with its increase in milk during the lactation period of cows. 展开更多
关键词 Bovine mammary epithelial cell Lactogenic differentiation microRNA MILK SECRETION
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Interpretation of Climate Change and Agricultural Adaptations by Local Household Farmers: a Case Study at Bin County, Northeast China 被引量:8
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作者 YU Qiang-yi WU Wen-bin +6 位作者 LIU Zhen-huan Peter H Verburg XIA Tian YANG Peng LU Zhong-jun YOU Liang-zhi TANG Hua-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第7期1599-1608,共10页
Although climate change impacts and agricultural adaptations have been studied extensively, how smallholder farmers perceive climate change and adapt their agricultural activities is poorly understood. Survey-based da... Although climate change impacts and agricultural adaptations have been studied extensively, how smallholder farmers perceive climate change and adapt their agricultural activities is poorly understood. Survey-based data (presents farmers' personal perceptions and adaptations to climate change) associated with external biophysical-socioeconomic data (presents real-world climate change) were used to develop a farmer-centered framework to explore climate change impacts and agricultural adaptations at a local level. A case study at Bin County (1980s-2010s), Northeast China, suggested that increased annual average temperature (0.6&#176;C per decade) and decreased annual precipitation (46 mm per decade, both from meteorological datasets) were correctly perceived by 76 and 66.9%, respectively, of farmers from the survey, and that a longer growing season was conifrmed by 70%of them. These reasonably correct perceptions enabled local farmers to make appropriate adaptations to cope with climate change:Longer season alternative varieties were found for maize and rice, which led to a signiifcant yield increase for both crops. The longer season also affected crop choice:More farmers selected maize instead of soybean, as implicated from survey results by a large increase in the maize growing area. Comparing warming-related factors, we found that precipitation and agricultural disasters were the least likely causes for farmers' agricultural decisions. As a result, crop and variety selection, rather than disaster prevention and infrastructure improvement, was the most common ways for farmers to adapt to the notable warming trend in the study region. 展开更多
关键词 perception adaptation survey climate change agriculture
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Effect of Fiber Loadings and Treatment on Dynamic Mechanical, Thermal and Flammability Properties of Pineapple Leaf Fiber and Kenaf Phenolic Composites 被引量:2
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作者 M.Asim M.Jawaid +1 位作者 M.Nasir N.Saba 《Journal of Renewable Materials》 SCIE 2018年第4期383-393,共11页
This study deals with the analysis of dynamic mechanical,thermal and flammability properties of treated and untreated pineapple leaf fiber(PALF)and kenaf fiber(KF)phenolic composites.Results indicated that storage mod... This study deals with the analysis of dynamic mechanical,thermal and flammability properties of treated and untreated pineapple leaf fiber(PALF)and kenaf fiber(KF)phenolic composites.Results indicated that storage modulus was decreased for all composites with increases in temperature and pattern of slopes for all composites,having almost the same values of E′at glass transition temperature(Tg).The peak of the loss modulus of pure phenolic composites was shown to be much less.After the addition of kenaf/PALF,peaks were higher and shifted towards a high temperature.The Tan delta peak height was low for pure phenolic composites and maximum for 60%PALF phenolic composites.Cole-Cole analysis was carried out to understand the phase behavior of the composite samples.Thermogravimetric analysis(TGA)results indicated that pure phenolic composites have better thermal stability than PALF and kenaf phenolic composites.Vertical and horizontal UL-94 tests were conducted and showed pure phenolic resin is highly fire resistant.The overall results showed that treated KF composites enhanced the dynamic mechanical and thermal properties among all PALF/KF composites. 展开更多
关键词 Pineapple leaf FIBER KENAF FIBER PHENOLIC resin DYNAMIC MECHANICAL analysis thermogravimetric analysis FLAMMABILITY
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Three amino acid residues in the envelope of human immunodeficiency virus type 1 CRF07_BC regulate viral neutralization susceptibility to the human monoclonal neutralizing antibody IgG1b12 被引量:2
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作者 Jianhui Nie Juan Zhao +2 位作者 Qingqing Chen Weijin Huang Youchun Wang 《Virologica Sinica》 SCIE CAS CSCD 2014年第5期299-307,共9页
The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) ... The CD4 binding site(CD4bs) of envelope glycoprotein(Env) is an important conserved target for anti-human immunodeficiency virus type 1(HIV-1) neutralizing antibodies. Neutralizing monoclonal antibodies IgG1 b12(b12) could recognize conformational epitopes that overlap the CD4 bs of Env. Different virus strains, even derived from the same individual, showed distinct neutralization susceptibility to b12. We examined the key amino acid residues affecting b12 neutralization susceptibility using single genome amplification and pseudovirus neutralization assay. Eleven amino acid residues were identified that affect the sensitivity of Env to b12. Through site-directed mutagenesis, an amino acid substitution at position 182 in the V2 region of Env was confirmed to play a key role in regulating the b12 neutralization susceptibility. The introduction of V182 L to a resistant strain enhanced its sensitivity to b12 more than twofold. Correspondingly, the introduction of L182 V to a sensitive strain reduced its sensitivity to b12 more than tenfold. Amino acid substitution at positions 267 and 346 could both enhance the sensitivity to b12 more than twofold. However, no additive effect was observed when the three site mutageneses were introduced into the same strain, and the sensitivity was equivalent to the single V182 L mutation. CRF07_BC is a major circulating recombinant form of HIV-1 prevalent in China. Our data may provide important information for understanding the molecular mechanism regulating the neutralization susceptibility of CRF07_BC viruses to b12 and may be helpful for a vaccine design targeting the CD4 bs epitopes. 展开更多
关键词 HUMAN IMMUNODEFICIENCY virus type 1 CRF07_BC ENVELOPE GLYCOPROTEIN IgG1b12 NEUTRALIZING antibody single genome amplification
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Vacuum press drying studies on two fast-growing Indian wood species 被引量:1
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作者 Shailendra Kumar Rushikesh R.Topare Jitendra Nagar 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期857-862,共6页
Two fast-growing Indian species, Melia composita Benth. and Eucalyptus tereticornis Sm., which have different sets of physical properties, were dried together in a vacuum press dryer(VPD) under two drying conditions,i... Two fast-growing Indian species, Melia composita Benth. and Eucalyptus tereticornis Sm., which have different sets of physical properties, were dried together in a vacuum press dryer(VPD) under two drying conditions,i.e., above boiling point(ABP) and below boiling point(BBP). The ABP and BBP conditions were maintained by keeping the temperature constant at 75 ℃ and maintaining two pressure levels: 300 mm of Hg(ABP) and 450 mm of Hg(BBP). In order to understand pressure conditions at the core during vacuum drying, a cylindrical brass pipe was inserted in both wood cores and attached with pressure gauges placed outside of the VPD. The results indicate that the Melia wood core attained equilibrium pressure immediately with the pressure of VPD, while Eucalyptus attained it very slowly, reaching equilibrium at later stages of drying when cracks and checks advanced to the core.The drying rate was higher for Melia than Eucalyptus under both drying conditions. The drying rate of Melia(ABP) was higher than Melia(BBP), however, the drying rate for Eucalyptus(ABP) was not significantly different from the BBP drying rate. 展开更多
关键词 Vacuum press drying Melia composita Eucalyptus tereticornis Boiling point Wood core pressure
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Improving the Antioxidant Properties of Fermented Camel Milk Using Some Strains of <i>Lactobacillus</i> 被引量:3
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作者 Mahmoud Ibrahim El-Sayed Sameh Awad Nagwa Hussein Ismail Abou-Soliman 《Food and Nutrition Sciences》 2021年第4期352-371,共20页
This study aimed at improving the antioxidant capacity of fermented camel milk using some single strains of </span><span style="font-family:Verdana;"><i></span><i><span style... This study aimed at improving the antioxidant capacity of fermented camel milk using some single strains of </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lactobacillus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> (</span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. helveticus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">B-734</span><i><span style="font-family:Verdana;">, </span></i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">Lb. casei</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">subsp.</span><i> </i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">casei</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">B-1922,</span><i> </i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">Lb. paracasei</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">subsp.</span><i> </i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">paracasei</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">B-4560,</span><i> </i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">B-1445</span><i> </i><span style="font-family:Verdana;">or </span></span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:Verdana;">B-442), as well as evaluating the acceptability of the final products. The acidity, proteolysis degree, antioxidant activity, viscosity and organoleptic properties of fermented milk were assessed during 14 days of storage at 4</span><span style="font-family:Verdana;">&deg;</span><span style="font-family:Verdana;">C. Total phenolic content (TPC), DPPH radical scavenging activity, Ferrous ion chelating ability (FCA) and Ferric reducing antioxidant power (FRAP) assays were used to determine the antioxidant activity of fermented milks. The results indicated that fermented milks differed significantly (P < 0.05) in all studied parameters due to the type of starter culture used. During storage period, samples containing </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. helveticus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> had the highest proteolysis degree, while samples with commercial starter culture (control) showed the lowest degree of proteolysis. Fermented milks containing </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lactobacillus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> strains showed higher DPPH radical scavenging activity compared to those samples containing commercial starter culture. By the end of storage, there was a significant improvement (P < 0.05) in scavenging activity for all fermented milk samples. Regarding FCA, at the beginning of storage fermented milks containing </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. paracasei</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;">, </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> B-442 or commercial starter culture had the highest FCA values, while </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> B-1445 samples recorded the highest value at the end of storage. </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. helveticus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> samples had the highest TPC and FRAP values (P < 0.05) throughout the storage. There was a high significant correlation (P</span><span> </span><span style="font-family:Verdana;"><</span><span> </span><span style="font-family:Verdana;">0.0001) between the proteolysis degree and the values of FRAP and TPC. Samples containing </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> B-442, </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:Verdana;">B-1445 or commercial starter culture received the highest taste and overall acceptability scores while </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. helveticus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> samples were the lowest. It is recommended to use </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> B-442 and </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lb. rhamnosus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> B-1445 for producing fermented camel milk with high antioxidant activity and acceptability. 展开更多
关键词 Camel Milk Fermented Milk Antioxidant Activity Lactobacillus
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Radiolabeling of lacosamide using highly purified rhenium-188 as a prospective brain theranostic agent 被引量:1
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作者 H.A.El-Sabagh M.I.Aydia +1 位作者 A.M.Amin K.M.El-Azony 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第10期105-114,共10页
Rhenium-188 is prospectively effective for both diagnosis and radiotherapy as it appropriately emits gamma rays and beta particles.Lacosamide(LCM)is a newly approved antiepileptic medication for focal drug-resistant e... Rhenium-188 is prospectively effective for both diagnosis and radiotherapy as it appropriately emits gamma rays and beta particles.Lacosamide(LCM)is a newly approved antiepileptic medication for focal drug-resistant epilepsy.Rhenium-188 was separated with high elution yield and high purity using the new 188W/188Re generator based on the ZrSiW gel matrix.188Re-LCM was prepared with high radiochemical yield and high purity.Biodistribution of 188Re-LCM in normal Swiss albino mice was investigated to determine its utility as a potential brain therapy agent.The 188W/188Re generator was used to obtain 188Re based on the ZrSi188W gel matrix,and the chemical,radiochemical,and radionuclidic purity of the obtained 188Re was determined using inductively coupled plasma optical emission spectrometry(ICP-AES),a paper chromatography technique,and high-purity germanium(HPGe)detection,respectively,to assess its validity for LCM labeling.Various factors,such as the pH,reaction time,and LCM quantity,were therefore studied in order to improve the yield and purity of 188Re-LCM,as determined by various chromatographic techniques such as electrophoresis,thin layer chromatography(TLC),and highpressure liquid chromatography(HPLC).188Re was obtained with a high elution yield(75±3%)and a low 188W breakthrough(0.001±0.0001%).The maximum radiochemical yield of 188Re-LCM(87.5±1.8%)was obtained using 50 ll LCM(4 mM),250 ll stannous chloride(4.4 mM)at pH 4,100 ll 188Re(37 MBq),within 30 min,at room temperature(25±3C),as determined by TLC,electrophoresis,and HPLC techniques.Biodistribution analysis showed that 188Re-LCM was primarily localized in the brain(5.1%)with a long residence time(240 min). 展开更多
关键词 LACOSAMIDE 188Re 188W/188Re generator RADIOLABELING
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