民和盆地早白垩世晚期的孢粉组合

民和盆地的甘肃兰州柴家台地区,下白垩统河口组上亚组含有较丰富的孢粉化石。上亚组上部是以Ｓｃｈｉｚａｅｏｉｓｐｏｒｉｔｅｓ－Ｃｉｃａｔｒｉｃｏｓｉｓｐｏｒｉｔｅｓ为代表的孢粉组合,并可划分出上下两个亚组合,分别以Ｃｌａｓｓｏｐｏｌｌｉｓ－Ｓｃｈｉｚａｅｏｉｓｐｏｒｉｔｅｓ和Ｐｉｃｅａｐｏｌｌｅｎｉｔｅｓ－Ｃｉｃａｔｒｉｃｏｓｉｓｐｏｒｉｔｅｓ来表示。通过对主要孢粉属种地史分布规律的分析和与国内外各地同时代孢粉组合的对比,认为其地质时代是早白垩世晚期的Ａｐｔｉａｎ－Ａｌｂｉａｎ 期,上部的第二亚组合可能更晚,为Ａｌｂｉａｎ 期;孢粉化石产出的这段地层是迄今民和盆地所发现的下白垩统最高的层位     

中国晚三叠世孢粉植物群地理分区

我国晚三叠世孢粉化石十分丰富,经研究划分为南北两个孢粉植物群地理区,南方孢粉植物群自上而下由３个组合带构成：１）Ｍｉｃｒｈｙｓｔｒｄｉｕｍ－Ｚｅｂｒａｓｐｏｒｉｔｅｓ组合带,２）Ａｒａｔｒｉｓｐｏｒｉｔｅｓ－Ｔａｅｎｉａｅｓｐｏｒｉｔｅｓ组合带,３）Ｋｙｒｔｏｍｉｓｐｏｒｉｓ－Ｏｖａｌｉｐｏｌｌｉｓ组合带;北方孢粉植物群由２个组合带构成：１）Ｄｕｐｌｅｘｉｓｐｏｒｉｔｅｓ－Ｐａｒａｔａｅｎｉａｅｓ     

海南岛东部近海新第三纪孢粉植物群

根据ＢＤ２３－１－１井与孢子花粉共生的海相浮游有孔虫和钙质超微化石,论述了中国海南岛东部近海新第三纪各个时期的孢粉植物群特征。建立了４个孢粉组合,它们是：１．Ｑｕｅｒｃｏｉｄｉｔｅｓ－Ｃｕｐｕｌｉｆｅｒｏｉｐｏｌｅｎｉｔｅｓ－Ｆｌｏｒｓｈｕｅｔｚｉａ－Ｄｉｃｏｌｐｏｐｏｌｉｓ组合（早中新世晚期）;２．Ｄｉｃｏｌｐｏｐｏｌｉｓ－Ｅｘｔｒａ－ｐｕｎｃｔａｔｏｓｐｏｒｉｔｅｓ－Ｔａｘｏｄｉａｃｅａｅｐｏｌｅｎｉｔｅｓ组合（中中新世早期）;３．Ａｂｉｅｔｉｎｅａｅｐｏｌｅｎｉｔｅｓ－Ｐｏｌｙｐｏｄｉ－ａｃｅａｅｓｐｏｒｉｔｅｓ－Ｌｉｑｕｉｄａｍｂａｒｐｏｌｅｎｉｔｅｓ组合（中中新世晚期至晚中新世）;４．Ａｂｉｅｔｉｎｅａｅｐｏｌｅｎｉｔｅｓ－Ｐｅｒｓｉｃａｒｉｏｉｐｏｌｉｓ组合（晚中新世晚期至早上新世）。孢粉植物群反映了海南岛东部近海新第三纪的气候基本上一直比较温暖湿润,并且逐渐降温的历程。     

新疆吐鲁番─哈密盆地晚三叠世黄山街组、郝家沟组孢粉植物群及其意义

本文对新疆吐鲁番－哈密盆地３口石油探井中黄山街组、郝家沟组共１０８块样品进行了孢粉分析研究。自下而上建立了晚三叠世两个孢粉组合,即Ａｒａｔｒｉｓｐｏｒｉｔｅｓ－Ａｌｉｓｐｏｒｉｔｅｓ组合和Ｏｓ－ｍｕｎｄａｃｉｄｉｔｅｓ－Ｃｈｏｒｄａｓｐｏｒｉｔｅｓ组合,讨论了组合特征及其时代,并与国内外有关层位及化石群进行了分析比较;探讨了孢粉植物群所反映的古植被和古气候。     

新疆吐鲁番—哈密盆地晚三叠世黄山街组,郝家沟组孢粉植物群及其意义

本文对新疆吐鲁番－哈密盆地３口石油探井中黄山街组,郝家沟组共１０８块样品进行了孢粉分析研究。自下而上建立了晚三叠世两个孢粉组合,即Ａｒａｔｒｉｓｐｏｒｉｔｅｓ－Ａｌｉｓｐｏｒｉｔｅｓ组合和Ｏｓｍｕｎｄａｃｉｄｉｔｅｓ－Ｃｈｏｒｄａｓｐｏｒｉｔｅｓ组合,讨论了组合特征及其时代,并与国内外有关层位及化石群进行了分析比较;探讨了孢粉植物群所反映的古植被和古气候。     

甘肃玉门旱峡早白垩世孢粉组合

本文研究了甘肃玉门旱峡沟口剖面下沟组,中沟组的孢粉化石,共鉴定孢粉３７属５３种;藻类化石２属２种。根据上孢粉化石建立了Ｃｉｃａｔｒｉｃｏｓｉｓｐｏｒｉｔｅｓ－Ｓｃｈｉｚａｅｏｉｓｐｏｒｉｔｅｓ－Ｃｌａｓｓｏｐｏｌｌｉｓ－Ｊｉａｏｈｅｐｏｌｌｉｓ组合,包括下亚组合,包括下晋组合（下沟组）和上亚组合（中沟组）。鉴定组合地质时代为Ｈａｕｔｅｒｉｖ－ｉａｎ－Ｂａｒｒｅｍｉａｎ。推测气候属于温暖湿润的亚热带     

民和盆地早白晋世晚期的孢粉组合

民和盆地的甘肃兰州柴家台地区,下白垩统河口组上亚组含有丰富的孢粉化石。上亚组上部是以Ｓｃｈｉｚａｅｏｉｓｐｏｒｉｔｅｓ－Ｃｉｃａｔｒｉｃｏｓｉｓ ｐｏｒｉｔｅｓ为代表的粉组合,并可划分出上下两个亚组合,分别以Ｃｌａｓｓｏｐｏｌｌｉｓ－Ｓｃｈｉｚａｅｏｉｓｐｏｒｉｔｅｓ和Ｐｉｃｅａｐｏｌｌｅｎｉｔｅｓ－Ｃｉｃａｔｒｉｃｏｓｉｓｐｏｒｉｔｅｓ来表示。     

塔里木盆地北部早白垩世孢粉组合

根据建组部面和４个钻井剖面舒善河组孢粉化石的研究,建立５个孢粉组合,自老而新为Ｃｌａｓｓｏｐｏｌｌｉｓ－Ｓｃｈｉｚａｅｏｉｓｐｏｒｉｔｅｓ组合,Ｃｌａｓｓｏｐｏｌｌｉｓ高含量组合,Ｃｌａｓｓｏｐｏｌｌｉｓ－Ｄｉｃｈｅｉｒｏｐｏｌｌｉｓ组合,Ｃｌａｓｓｏｐｏｌｌｉｓ－Ｄｉｃｈｅｉｒｏｐｏｌｌｉｓ－Ｌｙｇｏｄｉｕｍ－ｓｐｏｒｉｔｅｓ组合和Ｄｉｃｈｅｉｒｏｐｏｌｌｉｓ高含量组合。根据舒善河组的时代为早白     

新疆鄯善照壁山克拉玛依组孢粉组合

本文研究了新疆鄯善照壁山沟口克拉玛依组顶部的孢粉化石,共鉴定孢粉４６属７０种,命名为Ｐｕｎｃｔａｔｉｓｐｏｒｉｔｅｓ－Ａｒａｔｒｉｓｐｏｒｉｔｅｓ－Ｔａｅｎｉａｅｓｐｏｒｉｔｅｓ－Ｐａｒａｔａｅｎｉａｅｓｐｏｒｉｔｅｓ组合。根据组合主要分子的时限及其含量变化,以及与有关已知时代孢粉组合进行对比,鉴定其其他质时代为中三叠世。根据孢粉植物群反映当时为温湿的气候特征。     

新疆博乐早、中侏罗世火山沉积岩中的孢粉组合

研究的孢粉样品采自新疆博乐市保尔德苏河口东侧剖面，共发现抱粉化石３６属５１种。该孢粉组合以裸子植物花粉占优势（占７０．２％─９６．８％），其中以Ｑｕａｄｒａｅｃｕｌｉｎａ，Ｐｓｅｕｄｏｐｉｃｅａ，Ａｌｉｓｐｏｒｉｔｅｓ，Ｐｔｅｒｕｃｈｉｐｏｌｌｅｎｉｔｅｓ等的含量较高；蕨类植物孢子较少（占３．２％─２４．４％），主要有Ｃｙａｔｈｉｄｉｔｅｓ，Ｏｓｍｕｎｄａｃｉｄｉｔｅｓ，Ｎｅｏｒａｉｓｔｒｉｃｋｉａ，Ｌｙｃｏｐｏｄｉｕｍｓｐｏｒｉｔｅｓ，Ｄｕｐｌｅｘｉｓｐｏｒｉｔｅｓ等；还有很少苔鲜类植物孢子Ｓｔｅｒｉｓｐｏｒｉｔｅｓ。根据孢粉主要属种的已知时代分布和有关早、中侏罗世孢粉组合进行对比，笔者认为当前组合的时代应为早、中侏罗世，倾向于早侏罗世。     

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