大卫鼠耳蝠回声定位声波、翼型特征及夏季食性分析

2005 ～2009年,野外采集大卫鼠耳蝠(Myotis davidii)的回声定位声波、翼型数据及粪便样本,分析了其回声定位声波、翼型特征和夏季食性.结果表明,大卫鼠耳蝠回声定位声波主频为(60.4±10.0)kHz (Mean±SD),带宽为(54.7±8.5)kHz,能率环为7.4％±3.5％;翼展比为6.2±0...     

高颅鼠耳蝠回声定位声波特征与分析

在自建的野外实验事内,录制雌雄成体高颅鼠耳蝠Myotis siligorensis不同行为状态(飞行、爬行、手持)回声定位声波,利用单因素方差分析(One-Way ANOVA)对不同状态及不同性别的回声定位声波参数进行均值多重比较和显著性差异分析.结果 表明,高颅鼠耳蝠回声定位声波为长的宽频带调频(FM)声波,有1~3个谐波,但能量主要集中在第一谐波.不同行为状态下,高颅鼠耳蝠声脉冲持续时间、声脉冲间隔和能率环均存在显著性差异(P<0.05),第一谐波起始频率和终止频率、主频率、带宽差异不显著;第一谐波终止频率、带宽、声脉冲持续时间和能率环的性别差异显著(P<0.05),具有性别二态性.高颅鼠耳蝠回声定位声波特征体现了其在捕食策略和捕食生境方面的生态适应.     

大趾鼠耳蝠回声定位声波特征与分析

在12 m×4 m×4 m的围网内录制大趾鼠耳蝠(Myotis macrodactylus)飞行与悬挂状态下的回声定位声波,使用双尾t-检验对不同状态下的声波参数进行差异显著性分析.结果表明,大趾鼠耳蝠回声定位声波为短的、宽带的且能量主要集中在第1谐波的调频型声波,伴有1-2个谐波.第1谐波起始频率、带宽和声脉冲间隔在飞行与悬挂状态下具有显著差异(P<0.05).回声定位声波飞行状态下的第1谐波终止频率、带宽、声脉冲持续时间和声脉冲间隔均存在性别差异,而主频率没有显著的性别差异.回声定位声波的这些特征及差异体现了对其捕食生境、捕食策略及通讯行为的适应.     

蝙蝠回声定位声波的可塑性及其生态适应

蝙蝠通过调节回声定位声波特征来满足自身的感官需求,表现出回声定位声波的可塑性及其对生态环境与需求的适应。声波频率、强度、脉冲持续时间和间隔时间等特征与蝙蝠所处的生态位密切相关,声波可塑性在蝙蝠进化过程中起着至关重要的作用。本文结合马铁菊头蝠(Rhinolophus ferrumequinum)和大趾鼠耳蝠(Myotis macrodactylus)回声定位声波可塑性的研究,从回声定位声波的方向性、目标距离、环境复杂度和应对干扰4个方面总结了蝙蝠如何通过改变回声定位声波特征来满足自身在导航和捕捉猎物过程中的感官需求与生态适应,并阐述了回声定位声波可塑性的研究现状,为开展蝙蝠声学和行为学研究提供参考。     

拖网式食鱼蝠——大足鼠耳蝠的形态、回声定位声波及捕食策略

大足鼠耳蝠(Myotisricketti)是中国特有蝙蝠,其回声定位声波和捕食策略国内外均无报道,对大足鼠耳蝠该方面的研究报导是国内首次。大足鼠耳蝠体型较大,具有强大的后足,足上有强而有力的弯曲的爪,尾膜和距很长。大足鼠耳蝠回声定位声波为FM(调频)型,一般具有1～2个谐波,主频率较低(37.78±1.04kHz),调频带较宽(第一谐波频带宽为42.02±6.98kHz,第二谐波频带宽为25.79±7.89kHz),声脉冲时间较长(2.91±0.54ms),声脉冲间隔时间变化较大(32.30±15.10ms),能率环较高(11.27±5.84%);野外观察发现,大足鼠耳蝠主要在低水面上空飞行,利用大足从水面捕食猎物(拖网式捕食),猎物主要由鱼类组成。即分析和讨论了大足鼠耳蝠形态特征、回声定位特征和捕食策略的相互适应性。     

在不同状态和生境复杂度中大蹄蝠回声定位叫声的可塑性

蝙蝠回声定位声波的可塑性对其适应不同状态、生境以及捕食和社会交流具有重要的作用。为进一步研究大蹄蝠的回声定位声波在不同状态和生境下的可塑性,通过室内行为实验,对大蹄蝠在4 种不同状态(室内飞行、静息、布袋内和手持)和4 种不同生境复杂度(室外、室内0 棵树、室内1 棵树、室内5 棵树)条件下飞行的回声定位声波特征进行研究。结果表明:大蹄蝠的回声定位声波为CF - FM 型,通常连续发出2 - 4 个脉冲组成一个脉冲组。对比大蹄蝠在4 种不同状态下的回声定位叫声发现,主频按静息、布袋内、手持、飞行的顺序依次降低,后端FM 频宽则按手持、布袋内、飞行和静息的顺序依次变短;而脉冲间隔和脉冲时程则均按静 息、飞行、布袋内、手持的顺序依次增加。对比大蹄蝠在4 种不同生境复杂度中飞行的回声定位叫声发现,主频按室外、室内0 棵树、室内1 棵树、室内5 棵树依次提高,而脉冲时程及脉冲间隔则依次缩短;室外放飞条件下的后端FM 频宽比室内飞行的短。研究结果说明,大蹄蝠在不同状态、不同生境复杂度条件下的回声定位叫声具有明显的可塑性和生境适应性。     

中国渡濑氏鼠耳蝠种名订正

金黄鼠耳蝠Myotis formosus与渡濑氏鼠耳蝠M.rufoniger在物种识别及学名和中文名使用上一直混乱。以广东和江西采集的部分鼠耳蝠标本为研究对象,结合形态学和分子系统发育学方法对其进行分类厘定。结果显示,所采集的标本应为"渡濑氏鼠耳蝠",其形态特征却与国内文献中的"绯鼠耳蝠"(学名错用为M.formosus)形态描述相符合,结合历史文献,可确定国内鉴定的"绯鼠耳蝠"应为渡濑氏鼠耳蝠,国内分布区主要集中在中国东部,而近似种金黄鼠耳蝠仅在台湾和江西有分布记录。     

马铁菊头蝠幼蝠能够辨别种群间回声定位声波差异

蝙蝠的回声定位声波普遍存在地理变化,然而尚不清楚幼蝠在扩散前能否辨别不同种群间的声波差异。本文采用"双选择声学回放实验",研究马铁菊头蝠(Rhinolophus ferrumequinum)幼蝠(1月龄)对回声定位声波地理变化的辨别能力及行为反应。采用4个行为参数衡量幼蝠对本种群(CC)与外种群(JN)回声定位声波的行为反应:每一回放室飞入的次数、飞行时间、停留次数、探测时间。Mann-Whitney U tests表明,马铁菊头蝠1月龄个体对回放声波的行为反应,除每一回放室停留的次数外,其他3个参数均存在显著差异(P0.05),且在本种群声波回放室(CC)的飞行次数和时间以及探测时间均高于外种群声波回放室(JN)。对4个行为参数进行主成分分析,Mann-Whitney U tests表明,回放本种群声波(CC)与外种群声波(JN)之间,第一主成分得分(PC1)存在显著差异(P0.01)。配对T检验表明,幼蝠对本种群声波反应更加强烈(PC1:t10=5.25,P0.001;PC2:t10=2.34,P0.05)。本研究说明马铁菊头蝠幼蝠能够辨别不同种群间回声定位声波的差异。     

河南省绯鼠耳蝠新纪录

绯鼠耳蝠Myotis formosus又称丽鼠耳蝠、红黑鼠耳蝠等,隶属于翼手目Chiroptera蝙,蝠科Vespertilionidae蝙蝠亚科Vespertilioninae鼠耳蝠属Myotis.2006年12月20日于河南省南阳市桐柏山熊洞(2°62′N,113°68′E,海拔301 m)发现一冬眠群共31只色彩鲜艳的蝙蝠,仅采集5只,外形测量后分离头骨,毛皮做成剥制标本保存于河南师范大学生命科学学院标本馆.经进一步鉴定,确定为绯鼠耳蝠华南亚种Myotis formous rufoniger,为河南省蝙蝠新纪录.     

皮氏菊头蝠回声定位声波与年龄的关系

皮氏菊头蝠 (Rhinolophuspearsoni)雌性成体 5只和幼体 2只采自贵州省贞丰县珉谷镇。采用超声波探测仪 (D980 ,ULTRASOUNDDETECTOR)接收皮氏菊头蝠的回声定位声波 ,转换到原频率的 1 / 1 0后导入计算机 ,然后用专业声谱分析软件 (Batsound 3 1 0 )进行分析。成蝠在飞行和悬挂状态下的声波结构相似 ,只是声波各项参数值略有不同 :它们发射FM CF FM型声波 ,具有 2～ 3个谐波 ,主频率在飞行时为 5 6 80± 0 6 2kHz ,悬挂时为 5 8 0 5± 0 2 4kHz ;声脉冲时间和间隔在飞行时分别为 3 4 6 2± 5 2 9ms和 86 5 0± 1 9 72ms ,悬挂时分别为 4 1 0 8± 5 87ms和 1 1 7 2 9± 6 6 4 4ms ;能率环飞行时为 ( 4 4 0 6± 1 2 5 8) % ,悬挂时为 ( 4 6 0 0±2 4 2 5 ) %。幼蝠声波为CF FM型 ,谐波数为 5～ 8个 ,主频率明显低于成体 ,FM带宽窄于成体 ,声脉冲时间和间隔短于成体 ,能率环低于成体。皮氏菊头蝠回声定位声波与年龄有关 ,这可能因成体的声波主要是探测食物和周围环境的详细信息 ,而幼体主要是与母蝠进行交流。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.