新革螨属二新种记述：蜱螨亚纲：革螨股：寄螨科

记述新革螨属２新种：异形新革螨Ｎｅｏｇａｍａｓｕｓａｎｏｍａｌｕｓｓｐ．ｎｏｖ．和皱形新革螨Ｎｅｏｇａｍａｓｕｓｃｒｉｓｐｕｓｓｐ．ｎｏｖ。     

中国常革螨属一新种和一新纪录（蜱螨亚纲：中气门目：寄螨科）

本文报道常革螨属一新种和中国一新纪录,放射常革螨,新种Ｖｕｌｇ ａｒｏｇａｍａｓｕｓｒａｄｉａｌｉｓｓｐ．ｎｏｖ。采自新疆木垒的根田鼠,布尔卡常革螨Ｖｕｌｇａｒｏｇａｍａｓｕｓｂｕｒｃｈａｎｅｎｓｉｓ（Ｏｕｄｅｍａｎｓ,１９０３）中国新纪录,采自新疆巴音布鲁克的鸟巢。     

中国胭螨科一新种和五新记录种：蜱螨亚纲：胭螨科

本文记述中国胭螨科Ｒｈｏｄａｃａｒｉｄａｅ１新种－长白似革鞍螨Ｇａｍａｓｅｌｌｕｓ Ｃｈａｎｇｂａｉｅｎｓｉｓ,ｓｐ．ｎ．及５新记录种。模式标本保存于沈阳浓业大学植保系。     

革螨的异形(蜱螨亚纲)

在检视大量革螨标本中,发现异形标本４种９例。异形包括骨板变形和刚毛变位两种情况,现分别记述如下,供革螨分类鉴定和形态学研究时参考。１ 毒厉螨 Ｌａｅｌａｐｓ ｅｃｈｉｄｎｉｎｕｓ Ｂｅｒｌｅｓｅ,１８８７ 检视标本１６０８■■,发现异形４■■。１９７１年２-１０月采于吉林省前郭尔罗斯蒙古族自治县,寄主为褐家鼠 Ｒａｔｔｕｓ ｎｏｒｕｅｇｉｃｕｓ（Ｂｅｒｋｅｎｈｏｕｔ）。 标本１：胸板后缘明显凹陷,后凸的骨片消失（图１-２）,该处构造与正常标本不同。肛板花纹如图１,后部有一圆锥形构造,向后突出,ＰＡ位于其后…     

革索螨属一新种(蜱螨亚纲:寄螨科)

本文记述从青海省同德县河北乡的鸟巢中采集的革索螨属一新种,命名为同德革索螨,新种与中华革索螨１９９１较接近,但根据新种头盖形状和体毛较少可与后者相鉴别,模式标本保存在青海省地方病防治研究所。     

寄螨属1新种和革索螨属1新种(蜱螨亚纲:中气门目:寄螨科)

记述寄螨属1新种:简单寄螨Parasitus simplendogynii sp.nov.和革索螨属1新种:泾源革索螨Gamasodes jingyuanensis sp.nov.     

寄螨属一新种三新纪录（蜱螨亚纲：寄螨科）

本文记述采自宁夏自治区的寄螨Ｐａｒａｓｉｔｕｓ Ｌａｔｒｅｉｌｌｅ共６种,其中奇盖寄螨Ｐ．ｍｉｒａｔｅｃｔｕｓ ｓｐ．ｎｏｖ．是未曾描述过的种类;甲虫寄螨Ｐ．ｃｏｌｅｏｐｔｒａｔｏｒｕｓ、甜菜寄螨Ｐ．ｂｅｔａ与透明寄螨Ｐ．ｈｙａｌｉｎｕｓ为国内首次纪录。前此,我国曾记录７种寄螨,至此已有１１种。     

毛绥螨属一新种和中国二新记录种：蜱螨亚纲：囊螨科

本文民述囊螨科Ａｓｃｉｄａｅ毛绥螨属Ｌａｓｉｏｓｅｉｕｓ Ｂｅｒｌｅｓｅ,１９１６的１新种－中国毛绥螨Ｌａｓｉｏｓｅｉｕｓ ｓｉｎｅｎｓｉｓ ｓｐ．ｎ。及中国２新记录种－细孔毛绥螨Ｌ．ｐｏｒｕｌｏｓｕｓ Ｄｅ Ｌｅｏｎ与茸毛绥螨Ｌ．ｌａｓｉｏｄａｃｔｙｌｉ Ｉｓｈｉｋａｗａ。新种模式标本保存于沈阳农业大学植物保护系。     

胸前下盾螨和茅舍血厉螨若螨描述(蜱螨亚纲:革螨股:厉螨科)

在所查到的文献中,胸前下盾螨 Ｈｙｐｏａｓｐｉｓ ｐｒａｅｓｔｅｒｎａｌｉｓ Ｗｉｌｌｍａｎｎ,１９４９和茅舍血厉螨Ｈａｅｍｏｌａｅｌａｐｓ ｃａｓａｌｉｓ（Ｂｅｒｌｅｓｅ,１８８７）已描述了雌螨和雄螨［１－６］,本文描述这二种螨的后若螨及前若螨。１ 胸前下盾螨 Ｈｙｐｏａｓｐｉｓ ｐｒａｅｓｔｅｒｎａｌｔｓＷｉｌｌｍａｎｎ,１９４９ 后若螨（图１-３）体黄色,卵圆形,长宽 ３７９-４３７ Ｘ ２１８-２６４（４１４ Ｘ ２３９）μｍ。背板覆盖背面大部,有狭而深的侧切口,前区有刚毛２２对,后区有刚毛１７对,均光…     

西藏厚厉螨属一新种和毛绥属一新种

本文报道革螨二新种,西藏厚厉螨Ｐａｃｈｙｌａｅｌａｐｓ ｘｉｚｎｇｅｎｓｉｓ ｓｐ,ｏｖ,和亚东毛绥螨Ｌａｓｉｏｓｅｉｕｓ ｙａｄｏｎｇｅｎｓｉｓ ｓｐ,ｎｏｖ。,１９８５采自西藏亚东。     

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     

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.     

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.     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.     

Composition and diversity of bird communities in Swedish farmland–forest mosaic landscapes

CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.     

Chemical constituents from the fruits of Rhus typhina L. and their chemotaxonomic significance

This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.