不同温度和土壤含水量对大斑芫菁生长发育的联合作用

在室内人工饲养大斑芜蓄,研究了不同温度、土壤台水量对大斑芜蓄生长发育及其卵的孵化串的联合作用。结果表明：大斑芜蓄不同生长发育时期对温度、土壤台水量的要求有所不同,１—６龄幼虫发育速率最快时的温度和土壤台水量依次为：３２．６℃、６％;３５．６℃、６％;３６．３℃、６％;３８．０℃、６％;３５．６℃、６％;３８．０℃、７．１％,蛹发育速率最快时的温度、土壤台水量为３７．１℃、６％。卵孵化率最高时的温度、土壤台水量为３４．０℃、１２％,卵发育速率最快时的温度、土壤台水量为３３．２℃、７％,     

广西亚热带主要林型的树干茎流

１９８０～１９９１年对广西亚热带主要林型的树干茎流进行定位观测,结果表明：广西亚热带主要林型的年树干茎流量为６．２～６６．７ｍｍ,分别占林外降雨量０．５～３．３％;不同林型的年树干茎流率显示阔叶林或针阔叶混交林（占１．７～３．３％）大于针叶林（占０．５～１．４％）。树干茎流的大小主要受树皮的吸水性能、树木胸径、树干枝角与冠型结构、降雨量及降雨强度的影响。杉木林树干茎流营养元素的年平均浓度为８．７０７～１４．８４８ｐｐｍ,是林外雨年平均浓度（２．４５３～３．７５３ｐｐｍ）的３．０～６．０倍;是林内穿透雨年平均浓度（５．８６１～１０．４５４ｐｐｍ）的１．４～２．０倍。说明树干茎流具有重要的水文生态功能。     

人工落叶松林土壤动物生物量的研究

对不同林龄人工落叶松林的土壤动物生物量的研究表明,在不同林型中,大型土壤动物占总生物量的４１．６～６４．０％,中小型土壤动物为２４．４～３９．０％,湿生动物为８．９～２５％．在土壤动物各类群中,蚯蚓生物量最大,线虫类次之,线蚓最小．土壤动物生物量与凋落物量、植被总盖度、土壤ｐＨ、土壤含水量和土壤有机质含量呈正相关关系．     

气候因子对东北羊草草原羊草群落产量影响的分析

根据羊草［Ａｎｅｕｒｏｌｅｐｉｄｉｕｍ ｃｈｉｎｅｎｓｅ （Ｔｒｉｎ．） Ｋｅｎｇ］群落地上部产量的１３ 年定位观测资料,应用关联分析方法对羊草群落产量与主要气候因子动态的相互关系进行了探讨。分析结果表明,Σ７—８ 月降雨量、Σ６—８ 月降雨量／Σ６—８ 月温度和Σ４—７ 月日照对羊草群落产量的关联度,分别为０．４７、０．４１ 和０．３５。水分是羊草群落产量的主要限制因子,其次是水热因子的配合。并应用多元回归模型和周期方差分析方法的结合,对羊草群落产量进行了模拟,模拟率达９０％ 以上     

痤疮皮损区皮肤菌群的研究

本研究对皮肤常见病─—痤疮４０例病人皮损区的皮肤菌群进行了探讨,并以１０４例健康人面部皮肤菌群及８２例治愈后病人原皮损区菌群分析作为对照,结果痤疮病人皮损区中痤疮丙酸杆菌活菌数为４．５５±０．７３（ＣＦＵ以Ｌｏｇ／ｃｍ２计）。分离率为１００％,表皮葡萄球菌数为４．１９±０．７０（１００％）,微球菌数为２．７１±０．６９（６２．５％）,杆菌数为３．０９±０．６４（９０％）,需氧的革兰氏阴性杆菌数为３．３１±０．７６（３５％）,产色素微球菌数为３．０５±０．８２（４５％）,痤疮病人皮肤的皮损区内常住菌和过路菌都较健康人明显增加,差异显著（Ｐ＜０．０５或Ｐ＜０．０１）。而经皮肤微生态制剂治疗后痤疮病皮肤菌群与健康人几乎无差异（Ｐ＞０．０５）,说明皮肤微生态制剂具有调整皮肤菌群恢复微生态平衡,提高定植抗力的生理作用,故能较有效的治疗痤疮。     

辽河三角洲盐碱地防护林体系建设技术研究

辽河三角洲盐碱地上造林、土壤改良及营林工程技术试验结果表明,在土壤含盐量０．３％以下的干渠上应栽植辽宁杨、中林４６号杨、群众杨;结合土壤改良措施,在土壤含盐量０．４％左右的海堤上栽植刺槐、河南白榆,在含盐量为０．５２～０．７３％油田道路两侧则栽植绒毛白蜡;在土壤含盐量为０．９％左右的拦海防潮堤上,栽植中国柽柳．     

辽宁丹东地区柞树菌根真菌生态分布的研究

通过5年连续调查研究,发现辽宁丹东地区天然次生柞林中及部分柞树经济林中柞树菌根菌种类共有36种,隶属于7个科13个属,在此基础上研究分析了柞树菌根菌的生态分布与共生树种、树龄及季节的关系,结果表明,与蒙古栎共生的菌根菌种类最多,达29种;红菇属种类与柞树共生的树龄范围最广,鹅膏属种类偏重于与树龄较大的柞树共生;夏季的7、8月份为菌根菌发生的高峰期,75％的种类在7月份发生。100％的种类在8月份发生,8月中下旬菌根菌发生的相对密度最高,分别为19．5％和18．4％。     

~（14）C－涕灭威在旱田土壤中的降解

研究了１４Ｃ－涕灭威在５种土壤中（４ｐｐｍ,互．２２μＣｉ·５０ｇ－１土壤干重）的生物降解．模拟试验为密闭系统,土壤中水分含量为２２％,气温２０—３０Ｃ℃在供试的５种土壤中,北京肖家河的土壤降解最快,为施人放射剂量的５１．３％,以“ＣＯ：形式从土壤进出;２６．０％与土壤结合,只有２１．６％可以被抽出．取自浙江义乌的土壤降解较慢,收集到的１４ＣＯ２为施入量的２３．３％．土壤中加入杀菌剂红霉素或敌茵丹降解作用明显减慢．土壤提取物中涕灭威亚砜、涕灭威亚砜肟被确认是主要的代谢产物,还发现了少量的涕灭威砜,涕灭威亚砜腈涕灭威砜腈和涕灭威砜肟等降解物．     

甘肃省生态环境敏感性评价及其空间分布

为了促进生态环境建设和保护,实施宏观规划和管理,研究以甘肃省为案例,从方法论的角度,利用生态环境现状调查资料和相关研究成果进行了生态环境敏感性的综合评价,辩识出了甘肃省主要生态环境敏感区域。研究结果表明：(1)在生态环境调查的基础上,应用GIS空间分析方法进行生态环境敏感性评价具有可操作性和结果的可靠性。(2)甘肃省的生态环境敏感性区域分布比较广泛,极敏感区占全省面积的1．1％,高度敏感区占57．4％。其中水土流失极敏感区占0．21％,高度敏感区占24．6％,主要集中在黄土高原,甘南高原南部和北部,陇南山地的西礼盆地、徽成盆地等地区;沙漠化极敏感区面积占0．8％,高度敏感区面积占33．1％,主要集中在甘肃北部、安西中部地区和肃北的东南部;土壤盐渍化基本无极敏感区,高度敏感区域占1．1％,主要集中在疏勒河中下游、黑河中游以及石羊河下游。对于这些敏感区域的保护,应该是生态环境保护和建设的重中之重。     

黄土高原油松林地产流产沙及其过程研究

通过对径流小区的多年观测和人工模拟降雨试验,利用自制的径流自动记录装置,研究了油松林地不同处理的产流产沙及其动态过程。研究结果表明,油松林地、林地去枯枝落叶层和采伐林地上层林木等３种处理与农地比较,分别减少径流量８８．０％、２７．０％和８７．８％,减少产沙量９９．９％、９８．０％和９９．８％。产沙量与坡度和雨强关系密切,随坡度和雨强增加而迅速增加,以雨强的效应更甚。油松林地开始产流的降雨量一般在１     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various     

Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in Pakistan

<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV