Dietary Lipid Levels Affect the Growth Performance,Lipid Deposition,and Antioxidative Capacity of Juvenile Scaleless Carp,Gymnocypris przewalskii,on the Qinghai‐Tibetan Plateau

A 56‐d growth trial was conducted to evaluate the growth performance, lipid deposition, and antioxidative capacity of juvenile scaleless carp, Gymnocypris przewalskii, on Qinghai‐Tibetan Plateau. One‐year‐old juveniles (initial weight: 15.99 ± 0.02 g) were fed practical diets with different lipid levels of 4, 5.5, 7, 8.5, and 10%, respectively. Results showed that the best specific growth rate (SGR), feed conversion rate, and total antioxidative capacity (T‐AOC) in hepatopancreas were observed in fish fed the diet with 7% lipid level. Fish fed with high lipid diets (8.5 and 10%) had significantly higher condition factor and viscerosomatic index as well as lipid in muscle, intestine, mesenteric fat tissue, and whole body. Highest level of hepatopancreas lipase and lipoprotein lipases activities as well as malondialdehyde content and the lowest level of feed intake and T‐AOC content in hepatopancreas and intestine were also observed in fish fed with high lipid diets (8.5 and 10%) (P < 0.05). In conclusion, based on SGR and hepatopancreas T‐AOC content, dietary lipid requirement of juvenile G. przewalskii was estimated to be 7.35 and 7.39%, respectively.     

Identification,characterization and full-length sequence analysis of a novel endornavirus in common sunflower (Helianthus annuus L.)

To identify the possible quarantine viruses in seven common sunflower varieties imported from the United States of America and the Netherlands, we tested total RNAs extracted from the leaf tissues using next-generation sequencing of small RNAs. After analysis of small RNA sequencing data, no any quarantine virus was found, but a double-stranded RNA(dsRNA) molecule showing typical genomic features of endornavirus was detected in two varieties, X3939 and SH1108. Full-length sequence and phylogenetic analysis showed that it is a novel endornavirus, temporarily named as Helianthus annuus alphaendornavirus(HaEV). Its full genome corresponds to a 14 662-bp dsRNA segment, including a 21-nt 5′ untranslated region(UTR), 3' UTR ending with the unique sequence CCCCCCCC and lacking a poly(A) tail. An open reading frame(ORF) that encodes a deduced 4 867 amino acids(aa) polyprotein with three domains: RdRP, Hel and UGT(UDP-glycosyltransferase). HaEV mainly distributed in the cytoplasm but less in the nucleus of leaf cells by fluorescence in situ hybridization(FISH) experiment. This virus has a high seed infection rate in the five varieties, X3907, X3939, A231, SH1108 and SR1320. To our knowledge, this is the first report about the virus of the family Endornaviridae in the common sunflower.     

新的信息资源环境下图书馆员角色转变的思考

本文分析了信息时代图书馆员角色转变的几个重要因素及特点,揭示了新时代图书馆员应承担的几种重要角色,对信息时代图书馆员的发展进行了探讨.     

农地租赁均衡价格影响因素分析

在一定的经济技术条件下,农地资源的合理配置和有效利用,取决于与之相关的一系列农地制度实施机制.文章基于产权理论、地租理论、土地供给与需求理论,以农地租赁均衡价格为切入点,对农地租赁的利益来源、均衡价格形成与演变影响因素进行了分析与探讨.结果认为,影响农地租赁均衡价格的因素主要是市场机制、政府机制以及习俗元制度.     

国外绿色农业科技信息资源建设与启示

分别从绿色农业科技信息网站、数据库、多媒体服务平台、科技咨询、研究机构和专业协会合作组织等几个方面深入研究了国外绿色农业科技信息资源建设情况及成功经验,提出了对北京市相关工作的对策建议。     

银川地区羊肝中阿苯达唑(丙硫苯咪唑)残留情况的调查

阿苯达唑又称丙硫苯咪唑或丙硫咪唑，有时又称抗蠕敏，是目前国内常用的驱虫效果好、范围广、毒性较低的兽用驱虫药。随着家庭舍饲养羊规模的不断扩大，饲养者为了减少因寄生虫导致的死亡并增加育肥效果，常把阿苯达唑作为育肥前预防驱虫或寄生虫病治疗的首选药，出现了滥用或超剂量使用的现     

漆树酶在漆酚树脂上的固定化研究

介绍了漆酚树脂吸附金属离子后对漆树酶的固定化方法，比较了Ｆｅ＾３＋和Ａｌ＾３＋、漆酚树脂和漆酚－水杨酸接枝树脂对漆树酶的固定化结果显示，漆酚－水杨酸－Ａｌ螯合树脂对漆树酶的固定化活力最高，测定了溶液ＰＨ，环境温度对固定化漆树酶活性的航固定化漆酶的重作用性。另外，测定了固定化漆树酶的米氏常数，Ｋｍ＝４．９×１０＾－３，并讨论了Ｋｍ小于天然漆树酶的米氏常数的原因。     

Spring Barley Responses to Row Spacing and Fungicide Triadimefon in Regions with a Short Crop-growing Season

Aspects of intensive management practices such as high-yielding cultivars, narrow-row spacings and fungicide treatments could potentially increase cereal yields in regions with a short crop-growing season and occasionally dry and hot weather. A field experiment was carried out at McGill University, Canada for three years (1987 to 1989) to test the effects of triadimefon (1-[4-chlorophenoxy]-3,3-dimethyl-1-[1H-1,2,4-triazol-1-yl]-2-butanone, or Bayleton, a trade name) fungicide (0 vs. 140 g a.i. ha⁻¹) and row spacing (10 vs. 20 cm) on the yield components, yield and other agronomic traits (spike emergence, days to maturity, leaf disease and plant height) of spring barley ( Hordeum vulgare L.) cv. Cadette, Laurier and Leger. A cultivar by row spacing interaction resulted in a 11 to 13.5 % increase in grain yield due to narrow rows for Laurier in two out of the three years and up to 16 % for Leger in one year. Over the three years grain yields were on average increased 6 to 12 % due to use of the narrower row spacing. Fungicide application to barley at the early heading stage effectively controlled leaf diseases without influence on yield components or grain yield. Our results indicate that some components of intensive management such as narrow row spacing can be applicable in regions with a short crop-growing season.     

几种楼梯面可视化快速参数建模方法

楼梯面的智能化建模问题是建筑、装饰等行业的热点问题．以AutoCAD VBA作为开发工具．给出几种楼梯面可视化参数快速建模方法，并对楼梯面的生成算法进行了探讨．使楼梯面模型的设计更具敏捷化、智能化和可交互性．开发的设计程序可作为AutoCAD命令嵌入到的AutoCAD绘图软件中．以提高用户的设计效率。     

NM－1号抗旱剂的研究

试验结果表明谷子在—１３．９Ｐａ的负压下发芽率只有２４．０％，在—１６．７３Ｐａ时发芽率为１６．３％。用０．５％的ＮＭ—１号抗旱剂包衣后，在—１６．７３Ｐａ的负压下发芽率可达６５．６％，比对照提高４９．３％。同０．５％的ＮＭ—１抗旱剂在大豆现蕾期喷施叶面１次，相对收获株率为１１５．３８％，相对千粒量为１０７．７％，增产率为４０，２７％。玉米在６叶期喷施０．５％的抗旱剂后，饱和亏减少４．０９ｇ，是对照的４３．８１％；干物质积累比对照快６７．１９％，蒸腾系数减少８．３６ｇ。