笼养大紫胸鹦鹉的活动时间分配

研究了笼养大紫胸鹦鹉的行为活动和时间分配。结果表明：笼养大紫胸鹦鹉一天中除静栖外,其余各行为所占时间比例在中午较小,而在早晚较大;在一年中不同月份间各种行为活动所占时间比例也有变化,呈明显的年周期和日节律;节律变化与日出、日落时间、季节、温度等变化有关。大紫胸鹦鹉各种行为活动所占比例分别为静栖４５．５５％、身体护理１６．６６％、取食１４．５１％、运动１０．６０％、在巢８．９８％、繁殖２．５５％、社     

四川小寨子沟国家级自然保护区绿尾虹雉的日活动行为特征

2017年4—8月,利用瞬时扫描法和红外相机调查法对四川小寨子沟国家级自然保护区绿尾虹雉Lophophorus lhuysii的日活动行为进行了研究,结果表明:1)春、夏季绿尾虹雉的活动时间主要用于移动(38.04%),其次是取食(33.96%)、观望(17.01%)和静栖(7.05%),用于社会(2.14%)、保养(1.54%)和繁殖(0.27%)的时间较少;2)取食行为早晚的频次较高,静栖和保养行为在午后具有明显高峰,社会行为在清晨和夜宿前达到峰值;3)静栖、社会和保养行为节律存在性别和季节差异,繁殖行为节律存在性别差异;4)与笼养种群相比,野生绿尾虹雉的取食时间占比更大,静栖行为占比更少,移动、社会、繁殖和观望行为节律存在差异。了解野生绿尾虹雉的行为特征是保护该物种的重要基础,同时也可为人工圈养种群的管理提供参考,今后应重视其野外生态学研究工作。     

大鸨繁殖期活动时间预算和日节律

2000和2001年的4～7月连续两年,在内蒙古自治区科尔沁右翼前旗东南部的草原上,采用野外直接观察法对野生大鸨的活动时间预算和日节律进行了研究。结果表明,大鸨繁殖期的各种行为活动具有一定的时间分配,其时间预算存在着性别间的差异,同时随活动空间大小、食物条件以及繁殖阶段的不同而变化,在繁殖前期,大鸨的时间预算以取食、休息、行走、观察为主要行为,雄鸨和雌鸨的这4种行为分别占全部行为的87％和93％;到繁殖后期,雌鸨各种行为的时间和强度发生较大变化。大鸨在取食、休息和炫耀等行为上都存在不同程度的日节律,取食和炫耀出现两次高峰,中午大部分时间大鸨处于静栖休息状态。     

棕胸竹鸡觅食行为的观察

对笼养条件下棕胸竹鸡（Bambusicola fytchii fytchii）每日的觅食节律的时间、频次、求偶取食行为和社群等级之间的关系进行了观察。结果表明：影响棕胸竹鸡觅食行为的主要因素是一天中它在地面上活动、静栖、游走及饮水等项行为所占时间的长短。影响求偶取食行为的主要因素是它在地面上活动的总时间和理羽、攻击及其它的求偶活动所占的时间多少。社群等级对棕胸竹鸡的觅食行为有一定的影响,但不甚显著。     

人为干扰对白腹锦鸡活动节律的影响

人类足迹的扩张增加了人与野生动物的相互作用。理解自然保护地的濒危物种对人为干扰的响应有助于更好地保护濒危物种和指导保护管理。以往的研究表明野生动物在时空维度会对人类的干扰进行规避, 然而这类研究在野生雉类中还较少, 尤其是分布在人为干扰相对较强的中低海拔区域的雉类, 如白腹锦鸡(Chrysolophus amherstiae)。2017年11月至2018年10月, 我们在中国西南部的一个亚热带森林保护区中使用红外相机陷阱技术对白腹锦鸡和人为干扰进行调查, 并研究了白腹锦鸡在时空维度对3种不同类型人为干扰(人类活动、放牧和家养动物活动)的响应及其季节变化。结果表明, 白腹锦鸡在空间维度并未对人为干扰进行规避, 而在非繁殖季节的活动节律上对人为干扰在时间维度上进行了规避。具体而言, 白腹锦鸡在全年和非繁殖季节的活动高峰集中在17:30-18:30, 明显避开中午的人类活动高峰; 而在繁殖季节, 白腹锦鸡活动水平明显提高, 和人为干扰的重叠度很高, 可能是由于求偶、占区等繁殖行为使得白腹锦鸡无法规避人为干扰。此外, 在人为干扰强度较高的位点, 白腹锦鸡倾向于通过改变其日活动节律, 将活动高峰期推迟至傍晚以降低与人为干扰的重叠度, 进一步说明白腹锦鸡可通过调节其自身的日活动节律从而避开高强度的人为干扰。由于白腹锦鸡地面营巢和春夏季繁殖, 自然保护区管理部门可通过管理人为活动, 尤其在繁殖季节通过控制放牧和猫狗的活动来帮助白腹锦鸡及其他地面营巢鸟类维持繁殖成功率。     

东方白鹳繁殖期行为时间分配及日节律

2009年3—6月,采用扫描取样法对在黄河三角洲国家级自然保护区内繁殖成功的4对东方白鹳的行为活动进行了观察,同时对东方白鹳在繁殖期的行为时间分配和日节律进行了研究。结果表明:繁殖期各行为时间所占比例依次是繁殖22.17%±21.69%(其中孵化19.75%±20.71%,晾卵1.31%±2.16%,育幼1.00%±1.01%,交配0.11%±0.32%),静栖19.09%±13.94%,修巢6.40%±5.92%,警戒3.94%±4.88%,理羽3.11%±2.31%,其他行为45.27%±11.08%;在繁殖不同时期各行为差异显著(P0.01)。东方白鹳在繁殖期不同阶段行为活动存在一定节律,并且不同阶段日节律明显不同。此外,温度与晾卵(r=0.810,P0.01)、孵化(r=-0.518,P0.01)行为显著相关;车辆数与警戒(r=0.745,P0.01)、静栖(r=0.612,P0.01)行为显著相关。     

扎龙湿地白鹤春季停歇地昼间行为时间分配及活动规律

在2004年4～5月,采用瞬时扫描取样法对扎龙国家级自然保护区林甸芦苇沼泽区的野生白鹤(Grusleucogeranus)在春季迁徙停歇地的昼间各种行为进行了研究。结果表明,在整个观察时期内白鹤各种行为具有较强的规律性,活动时间分配比例为:觅食31%、游走27%、静栖19%、警戒17%、修饰6%。白鹤觅食行为在一天中有两个高峰,分别为早晨和黄昏;游走行为基本上与觅食行为呈正相变化,并且几乎每个游走高峰及低潮相应地伴随着觅食的高峰和低潮;由于渔民清晨下苇塘收鱼和放牧,在5:30～6:30和6:30～7:30两个时间段警戒行为比例最高;静栖行为基本与游走及觅食行为呈负相关,对比发现,静栖行为比例低于觅食行为,与笼养鹤类的情况存在一定的差异,原因可能是食物丰富度影响了野生状态下行为的时间分配;修饰行为所占比例较小,是由于修饰行为是非主要行为,其发生是随机的。天气状况对白鹤数量变化有一定影响,阴雨和大风天气,白鹤数量明显减少,鹤群转移。与正常天气情况相比,阴雨和大风对白鹤觅食、静栖和游走行为时间分配影响显著(P阴雨=0·000<0·05,P大风=0·000<0·05),觅食时间缩短,游走行为减少,静栖时间变长。     

笼养海南(开鸟)的活动时间分配

2003年10月至2004年4月,在对海南[开鸟]进行驯养的基础上,采用全部事件取样法研究了笼养海南[开鸟]的活动时间分配。结果表明：笼养海南[开鸟]一天中除静栖和静立外,其余各行为所占时间比例在白天极少,而在晨（5：00～7：00am）、昏（19：00～21：00pm）和午夜（23：00～1：00am）较大,呈明显的日活动节律;节律变化与季节有关;海南[开鸟]各种行为活动所占比例依次为静栖82．48％、静立8．64％、运动5．36％、取食1．97％、身体护理1．30％、其它0．25％。其时间分配不受季节（春、秋、冬季）影响。     

笼养绿孔雀繁殖行为的观察

１　观察方法　３～５月在孔雀繁殖最活跃的季节,每周利用双休日带同学到动物园观察１ｄ,时间是８∶００～１９∶００,共观察１０ｄ。对动物园２号笼的４只成年绿孔雀（１∶３♀）进行重点观察,对其它笼内的孔雀作对照观察。采用目标动物取样法进行观察,电子计时器计时,观察绿孔雀的求偶行为,交尾行为等。２　观察结果２．１　繁殖期绿孔雀日活动时间分配（２４ｈ）　通过１０ｄ观察,繁殖期绿孔雀日活动时间分配见图１,图中绿孔雀静栖行为占６０．４２％,在时间分配中占的比例最大,求偶行为占１６．６７％,居第２位。说明进入…     

笼养白腹锦鸡(Chrysolophus amherstiae)夏、秋季行为节律

为了解笼养白腹锦鸡夏秋季行为节律规律,于2016年6月、9月和10月对湖南省野生动物救护繁育中心笼养的6只白腹锦鸡采用瞬时扫描法开展行为节律研究,分别统计了白腹锦鸡夏、秋两季节行为的时间分配。观测期间共记录到白腹锦鸡行为16种,根据其行为的功能再归纳为运动、静止、取食、梳理和警觉5大类,其中以运动类行为比例最高。在夏季,静止类行为波动最剧烈,多数时间段中,运动类行为比例最大。相对夏季,5类行为秋季比例趋势更加平稳清晰,运动类行为依旧是发生最多的一类行为,静止类行为起伏还是最剧烈的。警觉类行为不突出,警觉行为占有比例偏少。本研究与之前的白腹锦鸡发情期时间分配研究结果相近,运动和静止是笼养白腹锦鸡发生较多的两类行为,不同的是本研究白腹锦鸡梳理类行为比例有明显上升。     

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.