四川青城山优食蚜蝇属二新种记述（双翅目：食蚜蝇科）

本文记述四川青城山优食蚜蝇属Eupeodes 2新种:青优食蚜蝇Eupeodes (Eupeodes) qingchengshanensis和小优食蚜蝇Eupeodes(Eupeodes)parvus,均属于Eupeodes s.str.,亚属。模式标本保存于上海农学院昆虫标本室。     

毛食蚜蝇属二新种（双翅目：食蚜蝇科）

本文记述毛食蚜蝇属Dasysyrphus 2新种,雄性外生殖器命名采用Vockeroth(1969)系统。模式标本保存于上海农学院昆虫标本室。1.曲毛食蚜蝇Dasysyrphus licinus He,新种(图 1) 雄体长10.5mm。眼毛褐色,长约0.2mm。头顶三角区的高度约等于复眼接合缝的长度,覆淡色粉被及黑毛。单眼黄褐色,排成短的等腰三角形。额黑色,被黄色绵毛     

长白山地区食蚜蝇科二新种记述(双翅目,食蚜蝇科)

在整理吉林省长白山地区的食蚜蝇标本时,发现2新种,分别为拟食蚜蝇属1新种,郑氏拟蚜蝇Parasyrphus zhengi sp.nov.,新种近似直带拟蚜蝇Parasyrphus lineola(Zetterstedt,1843),但新种复眼裸,翅暗黑色,足被黑毛,中足胫节端部黑色;长角蚜蝇属1新种,黑缘长角蚜蝇Chrysotoxum nigrimarginatum sp.nov.,新种近似侧宽长角蚜蝇Chrysotoxum fasciolatum(De Geer,1776),与C.fasicolatum的主要区别是新种腹部背板侧缘黑色,触角3节长度之比为1∶1∶4,后者腹部背板黑、黄相间,触角3节长度之比(背面观)约为0.8∶1.0∶3.0。本文除记述新种外,同时提供其特征图。模式标本保存在陕西理工学院动植物标本馆。     

中国优食蚜蝇属的研究及二新种记述(双翅目：食蚜蝇科)

１研究历史与现状优食蚜蝇属Ｅｕｐｅｏｄｅｓ是１８７７年由ＯｓｔｅｎＳａｃｋｅｎ建立,但自从Ｍａｔｓｕｍｕｒａ于１９１７年建立后食蚜蝇属Ｍｅｔａｓｙｒｐｈｕｓ以来的近７０年中,许多作者均采用后一属名。Ｆｌｕｋｅ［１］将该属分成２亚属,即后食蚜蝇亚属Ｍｅ...     

中国食蚜蝇属一新种记述(双翅目：食蚜蝇科)

中国食蚜蝇属一新种记述（双翅目：食蚜蝇科）何继龙,储西平（上海农学院园林环境科学系上海２０１１０１）（江苏省农业科学院植物保护研究所南京２１００１４）食蚜蝇属Ｓｙｐｈｕｓ是Ｆａｂｒｉｃｉｕｓ建立于１７７５年。此时的食蚜蝇属Ｓｙｒｐｈｕｓ（ｓ．１．）是...     

中国毛食蚜蝇属研究及二新种记述(双翅目,食蚜蝇科)

2001～2003年作者对秦巴山区食蚜蝇科昆虫调查,发现中国毛食蚜蝇属Dasysyrphus 2新种,模式标本保存于陕西理工学院生物系陕西省资源生物重点实验室动植物标本馆.文中给出中国已知种的检索表.     

中国长角食蚜蝇属一新种及一新纪录种(双翅目,食蚜蝇科)

记述了中国长角食蚜蝇属1新种：紫柏长角食蚜蝇Chrysotoxum zibaiensis sp．nov．,模式标本保存于陕西理工学院生物系陕西省资源生物重点实验室动植物标本馆。中国1新纪录种：弓斑长角食蚜蝇Chrysotoxum arcuatum（Linneaus,1758）。 紫柏长角食蚜蝇。新种Chrysotoxum zibaiensis sp．nov．（图1-8） 雌性 未知。 ♂体长12mm,翅长12mm。 正模♂,凤县,2003-06-27;副模1♂,留坝,2003—06—26,霍科科采。 新种近似天台长角食蚜蝇Chrysotoxum tiantaiensis,但新种腹部第1～2背板侧缘黄褐色区域宽,第3背板几乎整个黄褐色,第4背板侧缘黄褐色,第2、4、5背板后缘黄褐色,雄性尾器不同,新种尾器被毛黄褐色。 词源：新种种名以模式产地命名。 弓斑长角食蚜蝇Chrysotoxum arcuatum（Linneaus,1758）中国新纪录 观察标本：1♀,吉林长白山,1977-08-03～12。 国外分布：伊郎,蒙古,日本,欧洲,前苏联。     

长角蚜蝇属一新种记述：双翅目：食蚜蝇科

长角蚜蝇属一新种记述（双翅目：食蚜蝇科）李清西,何继龙新疆八一农学院植物保护系,新疆乌鲁木齐市８３００５２上海农学院园林环境科学系,上海市２０１１０１关键词食蚜蝇科,帽儿山长角蚜蝇,新种作者等在整理中国长角蚜蝇属标本时,发现了采自黑龙江的该属１新种。...     

云南西双版纳热带雨林地区的食蚜蝇（双翅目：食蚜蝇科）

本文共记述了云南西双版纳地区２３属３７种食蚜蝇。其中有１新种和中国１新纪录种,另外有２种在国外报道,我国台湾和海南有分布,但国内无任何记载和描述,本文对这些种类均进行了描述。同时还对该地区的食蚜蝇区系特点及不同生态环境下食蚜蝇多样性进行了初步分析。     

河北大学博物馆馆藏食蚜蝇亚科分类研究(双翅目,食蚜蝇科,食蚜蝇亚科)

在系统整理河北大学博物馆馆藏食蚜蝇科Syrphidae昆虫标本的基础上,鉴定出中国食蚜蝇亚科Syrphinae昆虫4族21属41种,其中5新种:直带垂边食蚜蝇Epistrophe rectistrigata sp.nov.,黑龙江美蓝食蚜蝇Melangyna heilongjiangensis sp.nov.,秦巴细腹食蚜蝇Sphaerophoria qingbaensis sp.nov.,秦岭细腹食蚜蝇Sphaerophoria qinglinensis sp.nov.和长白山食蚜蝇Syrphus changbaishanicus sp.nov..新种正模标本保存于河北大学博物馆,副模标本保存于陕西理工学院陕西省资源生物重点实验室.     

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.