红碱淖东方大苇莺繁殖生态

2012年5～7月,在陕西红碱淖对东方大苇莺的繁殖生态进行了研究。结果表明,东方大苇莺5月末迁来繁殖,营巢于芦苇丛中,巢口向上呈深杯状,由枯芦苇和芦苇絮编织而成。对17个巢的巢参数进行了测量:巢外径(11.85±0.216)cm,巢内径(5.87±0.101)cm,巢深(6.49±0.166)cm。巢距地面高度(106.00±4.421)cm,约位于芦苇高度的2/5处。平均窝卵数(4.67±0.188)枚,卵重为(2.70±0.044)g,卵长径为(21.93±0.13)mm,卵短径为(15.81±0.06)mm。孵化期为(15～18)d,孵化率为78.8%,巢雏成活率为95.2%。雏鸟的体重、体长的生长符合Logistic曲线方程拟合。芦苇的高度和密度是制约东方大苇莺巢址选择的主要因素,恶劣天气和大杜鹃巢寄生是影响繁殖成效的主要原因。     

甘肃莲花山黑冠山雀繁殖生态的初步研究

2017和2018年每年的4至8月在甘肃莲花山国家级自然保护区,对人工巢箱中黑冠山雀（Periparus rubidiventris）的繁殖生态进行了研究。共悬挂100个巢箱,两年共计招引到15巢黑冠山雀。此外,还记录到4个自然巢,分别位于干枯的糙皮桦（Betula utilise）树洞（1巢）、土坡的缝隙（1巢）和路边水泥护坡的出水管中（2巢）。黑冠山雀雌雄亲鸟共同筑巢,巢内壁为兽毛夹杂少量绒羽,外壁为草茎须根和苔藓。5月中下旬为黑冠山雀的产卵高峰期,清晨产卵,日产1枚,产下最后1枚卵后开始孵卵。平均窝卵数为6枚（4 ~ 7 枚,n = 15）,平均卵重（1.12 ± 0.02）g,卵长径（15.30 ± 0.10）mm,卵短径（12.09 ± 0.11）mm（n = 86）。孵卵由雌鸟承担,孵卵期为15 d（14 ~ 16 d,n = 5）。产卵期,雌鸟离巢时有用巢材盖卵的行为,开始孵卵后则不再盖卵。双亲共同育雏,育雏期为16 d和17 d（n = 2）。所记录的18巢黑冠山雀的繁殖成功率为83.3%,人工巢箱（15巢）中繁殖成功率为86.7%,巢捕食者主要为鼠类。     

陕西红碱淖白喉林莺繁殖生态

2012~2013年每年的4~7月,在陕西神木县红碱淖(39°04'21″~39°04'43″N,109°53'12″~109°53'40″E)对白喉林莺(Sylvia curruca)的繁殖生态进行了研究。结果表明,白喉林莺4月末迁来繁殖,5月初开始营巢于油蒿(Artemisia ordosia)、臭柏(Sabina vulgaris)和沙棘(Hippophae rhamnoides)灌丛中,巢口向上呈深杯状,巢由柳絮、枯枝和干草编织而成。对33个巢的参数进行了测量,巢外径(9.62±0.227)cm,巢内径(5.21±0.084)cm,巢深(5.05±0.160)cm,巢高(9.03±0.185)cm,巢距地面高度(24.91±1.084)cm,巢约位于植株高度的1/3处(由下而上)。营巢成功率为77.1%(n=35),窝卵数4~5枚(n=27),卵重(7.49±0.021)g,卵长径(17.27±0.057)mm,卵短径(12.86±0.080)mm(n=130)。孵化期为11~13 d,孵化率为93.1%,雏鸟出飞为90.9%。雏鸟的形态参数生长符合Logistic曲线方程拟合。植被高度、植被盖度和单株植物冠径是制约白喉林莺巢址选择的主要因素,同时恶劣天气和人为干扰是影响繁殖成效的主要原因。     

赛罕乌拉国家级自然保护区红角鸮(Otus scops)的繁殖生态观察

为了解红角鸮(Otus scops)的繁殖状态,2009年5～8月,在内蒙古赛罕乌拉国家级自然保护区,以直接观察法对红角鸮的繁殖生态进行了研究。结果表明,所观察的4个巢址全部是以柳树为主干的树洞巢,巢内铺垫物较少或无铺垫,巢距地面的平均高度为91.3cm,巢内径平均为13.5cm,巢外径平均为15.0cm,巢深平均32.0cm(n=4)。平均窝卵数为3.75,对其中一窝进行测量,4枚卵平均量度是28.9mm×24.6mm,重量9.5g。雏鸟孵出后,雌性亲鸟承担主要育雏任务,雄性亲鸟日间停歇于离巢不远的树上负责警戒工作,夜间与雌鸟共同哺育雏鸟。小型鼬科动物的捕食可能是干扰红角鸮繁殖成功率的主要因素。     

四川瓦屋山金色林鸲的巢址选择和繁殖记录

2010~2011年4~7月,在四川省瓦屋山自然保护区对金色林鸲(Tarsiger chrysaeus)的繁殖生态和巢址选择进行了研究。共发现26巢,金色林鸲2010年和2011年的繁殖成功率分别为43.8%和44.4%,孵化率分别为52.5%和60.0%;育雏成功率分别为85.7%和100.0%。主成分分析表明,影响金色林鸲巢址选择的主要因子包括巢位因素、苔藓盖度因素和乔木郁闭度因素。步道两侧的土坎为金色林鸲巢址选择提供了适宜条件。在瓦屋山,人类活动是影响金色林鸲繁殖、巢址选择、巢的分布和数量的重要因素,并存在两面性;人行步道的修建为金色林鸲提供了更多适宜的巢址,而游客的频繁活动限制了金色林鸲的繁殖活动。     

黑卷尾的繁殖生态行为观察

2007～2009年每年5～7月对四川省绵阳地区黑卷尾Dicrurus macrocercus的繁殖生态进行了观察.结果 表明,在绵阳,黑卷尾5月初迁入,5月中旬开始筑巢,巢深(6.73±1.41)cm、巢位高(6.38±1.27)m,巢内径为(9.88±1.54) cm,外径为(12.87±2.75) cm;5月底6月初产卵, 窝卵数多为3～5枚,平均卵重4.61 g,平均卵长径24.4 mm,平均卵短径17.4 mm;孵卵期(16±1) d,育雏期15～17 d,在幼鸟8～12日龄亲鸟育雏频次最高,平均为(8.23±2.13) 次/d.     

北红尾鸲在浙江清凉峰国家级自然保护区的繁殖记述

2015年和2016年的5—7月,在浙江清凉峰国家级自然保护区野外调查期间发现一处北红尾鸲Phoenicurus auroreus巢址,并对其繁殖习性进行了观察。结果表明:北红尾鸲在本地为冬候鸟,但首次发现该种鸟类夏季在此繁殖;北红尾鸲的繁殖期为5月下旬至7月中旬,5月下旬开始营巢,持续10 d左右,巢穴外径7.5 cm×5.8 cm、巢深3.2 cm,巢材由苔藓、体羽、禾本科杂草茎等组成;6月中旬产卵,窝卵数为4~5枚(2015年产卵4枚、2016年产卵5枚),孵化期11~12 d,巢内育雏14 d。推测冬候鸟北红尾鸲在此繁殖可能与气候变化有关。     

四川瓦屋山金色林鸲的繁殖生态及孵卵节律

20 0 3年 4～ 7月 ,在四川省瓦屋山自然保护区对金色林鸲 (Tarsigerchrysaeus)的繁殖生态和孵卵节律进行了较为深入的研究。金色林鸲营巢期从 4月下旬～ 6月中旬 ,孵卵期一般为 1 6～ 1 7d,育雏期为1 6d。窝卵数一般为 3～ 4枚 ,平均为 (3 . 75± 0. 45 )枚 (n =1 2 ) ,孵化率为 60 0 % ,育雏成功率为 85 2 %。仅雌鸟孵卵 ,根据对 3巢的监测 ,发现雌鸟早晨 6:0 0时左右首次离巢 ,晚上 2 0 :0 0时左右回到巢中 ,每天出巢次数 1 8～ 1 9次。孵卵雌鸟每次出巢时间一般少于 2 0min ,异常离巢时最长达到 65 6min。雌鸟出巢时间的长度和环境温度呈明显的正相关 (Spearman,r=0 . 1 1 8,P =0 . 0 0 7,n =5 3 1 )。金色林鸲雄鸟存在羽毛延迟成熟现象 ,亚成体雄鸟可以繁殖。     

云南云县黑喉山鹪莺繁殖生态初报

2016年3~9月对云南云县中岭岗村(24°15′42″N,100°02′42″E,平均海拔1 650 m)的黑喉山鹪莺(Prinia atrogularis)繁殖生态进行了研究。研究期间共发现42巢,主要位于杂草丛中(n=37)和灌木丛(茶树)中(n=5),筑巢期一般5~6 d,巢材有蜘蛛丝、苔藓植物、茅草花、茅草叶、铁线莲花、竹根须、枯枝、棕丝、干枯草穗等。巢呈球状,中上部侧方开口,巢重为(8.3±1.7)g,巢长为(13.2±0.9)cm,宽为(8.2±0.5)cm,巢口长(4.9±0.7)cm,巢口宽为(4.0±0.5)cm(n=25)。窝卵数为(3.9±0.4)枚(n=21,3~4枚)。卵的底色为白色、淡绿或者淡粉,遍布褐红色斑点,有的在钝端呈环状。卵重为(1.38±0.09)g,卵长为(17.3±0.7)mm,宽为(12.6±0.3)mm,卵体积为(1.4±0.1)cm3(n=65)。孵卵期(13.9±0.9)d(n=5,13~15 d),育雏期为(13.5±1.3)d(n=4,12~15 d)。利用Logistic曲线拟合雏鸟体重及外部器官增长,雏鸟的体重和嘴峰在5日龄左右增长最快,体长、翼长、跗跖在7日龄增长最快。对繁殖时间和地点较近的28巢进行连续观察,其中有7巢成功、21巢失败。造成繁殖失败的主要原因分别是巢捕食(62%)、亲鸟弃巢(14%)、人为破坏(14%)。     

内蒙古达赉湖国家级自然保护区短趾百灵繁殖生态学初报

本文对内蒙古达赉湖国家级自然保护区短趾百灵繁殖生态进行了初步研究,共记录到短趾百灵繁殖巢37个。筑巢期7~10 d。巢外径91.95 mm±3.85 mm(n=37),巢内径53.89 mm±3.29 mm(n=37),巢深43.62 mm±5.36 mm(n=37)。平均窝卵数3.05枚±0.51枚。孵卵期10~12 d。孵化率、离巢率和繁殖成功率分别为83.3%、94.1%和54.1%。雏鸟食性以直翅目昆虫幼虫为主。     

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.