四川老君山国家级自然保护区红翅噪鹛的繁殖生态研究

2014—2016年繁殖季,在四川老君山国家级自然保护区内对红翅噪鹛Trochalopteron formosum的繁殖生态进行了初步研究。结果显示,红翅噪鹛的繁殖期为4月下旬到9月中旬。在2016年,红翅噪鹛的繁殖种群密度为14. 733只/km2(95%置信区间:11. 727～18. 511;变异系数:0. 115),主要在八月竹Chimonobambusa szechuanensis上筑巢。在产卵期,雌鸟每天清晨产1枚卵,平均窝卵数为2. 28枚±0. 09枚(n=24;范围:2～3)。孵卵期14～15 d,孵化率约59. 6%。育雏期14 d,出飞率约50. 0%。天敌捕食是红翅噪鹛繁殖失败的首要原因。红翅噪鹛偏好乔木盖度低、竹子较高和竹子盖度较大的巢址生境。乔木盖度可能是影响红翅噪鹛巢址选择的关键生态因子。     

西藏林芝灰腹噪鹛(Garrulax henrici)繁殖生态及行为节律

灰腹噪鹛(Garrulax henrici)是中国的特有鸟种,也是噪鹛属中繁殖行为研究较少的物种之一。2016年4—7月,在西藏林芝西藏农牧学院内进行了灰腹噪鹛的繁殖生态研究,采用瞬时扫描法观察其求偶期日行为节律,用红外相机监测孵卵期3巢和育雏期2巢灰腹噪鹛的行为。结果表明:灰腹噪鹛4月中旬开始产卵,窝卵数2~3枚,卵长径29.6±0.4mm,短径20.3±0.17 mm,卵重6.66±0.12 g;灰腹噪鹛75.0%的巢树为针叶树,12.5%为阔叶树,8.3%为灌木,4.2%为禾本科;灰腹噪鹛营巢成功率为86.7%,孵化成功率为60%,繁殖成功率为43.3%,影响其繁殖成功率的因素是人为干扰和天敌捕食;求偶期灰腹噪鹛觅食行为占总时间的32.03%,移动占29.27%,上午觅食、移动及鸣唱行为达到高峰,下午休憩行为偏多;孵卵期的主要行为是卧巢孵卵,占总时间的85.31%,翻卵占5.02%;育雏期亲鸟理巢行为占39.74%,卧巢占35.92%,喂食频率平均为2.95次·h-1,灰腹噪鹛单亲喂食频次多于双亲共同喂食。     

鹰鹃在橙翅噪鹛巢中寄生繁殖

2011年和2012年每年的5月到8月,在甘肃莲花山地区共发现了5例鹰鹃(Hierococcyx sparverioides)在橙翅噪鹛(Garrulax elliotii)巢中寄生繁殖的案例.鹰鹃卵为椭圆形,浅蓝色,卵壳上没有斑点.测量了其中2枚卵,卵重分别为6.9g和7.2g,长径×短径分别为29.76 mm×20.40 mm和28.40mm×21.68 mm.鹰鹃幼鸟在出壳后的第20天离巢.     

贵州宽阔水自然保护区小杜鹃对小鳞胸鹪鹛的巢寄生

2015年4—8月,在贵州宽阔水国家级自然保护区记录到小杜鹃Cuculus poliocephalus在小鳞胸鹪鹛Pnoepyga pusilla巢中寄生繁殖。发现时小鳞胸鹪鹛已处于孵卵后期,巢内有1枚红棕色的小杜鹃寄生卵和3枚小鳞胸鹪鹛的白色卵。小杜鹃卵质量为2.55 g,体积2.72 cm~3,小鳞胸鹪鹛卵质量(1.64±0.16)g(n=7),体积(1.65±0.08)cm~3(n=7),两者的卵在颜色和大小上差别明显。光纤光谱仪对卵色的测量和分析结果表明,小鳞胸鹪鹛的卵色亮度显著高于小杜鹃,小杜鹃的卵为高度非模拟寄生卵。这是小鳞胸鹪鹛被小杜鹃寄生的第二例报道,说明其可能是小杜鹃的适宜寄主。     

绿翅鸭繁殖生态初报

2007～2009年在黑龙江中南部地区对绿翅鸭(Anas crecca)繁殖生态习性进行了观察。绿翅鸭在黑龙江属夏候鸟,每年3月末4月初迁来,10月上旬迁离,所观察的4对绿翅鸭居留期约6个月。迁来时成群停留在湖泊及江的冰面上,开江以后散去,繁殖期间,绿翅鸭的配偶关系为一雄一雌,巢址多选择离水域较近的草丛或灌木丛中,所观察的4巢,巢都比较简单,筑巢时间为(5.5±1.0)d(n=4)。巢筑成后的(3.25±0.50)d开始产卵。每窝70～12枚不等,平均(9.80±2.21)枚(n=4)。卵重平均(28.70±0.72)g(n=39),最后一枚卵产出后(2.50±0.577)d(n=4),开始孵卵,孵卵期约为22～26 d不等,平均孵卵期为(24.25±1.17)d(n=4),平均孵化率为79.5%±29.98%。幼鸟为早成鸟,育雏期为(29.75±1.70)d。     

甘肃莲花山暗绿柳莺的孵卵行为

2001年5～7月,在甘肃省莲花山自然保护区对暗绿柳莺Phylloscopus trochiloides的孵卵行为进行了初步研究.结果 表明,孵化期内雌鸟日活动期长度平均为(848.5±14.8) min (n=17),每天离巢(16.0±3.0)次(n=15),每次离巢时间为(12.3±5.0) min (n=251),每次在巢时间为(43.6±21.9) min (n=236),在巢率为(78.8±2.4)%.雌鸟在巢时卵温平均为(31.3±3.5)℃ (n=10646),离巢时卵温平均为(26.6±4.8)℃ (n=2876);夜晚的平均卵温为(30.6±3.5)℃ (n=9239).孵卵温度在孵卵期有逐渐上升的趋势.     

甘肃莲花山淡眉柳莺的繁殖记录及其孵卵行为

2001年6～7月,在甘肃省莲花山自然保护区记录了淡眉柳莺(Phylloscopus humei)繁殖,研究了其孵卵行为。结果表明,窝卵数为(4.3±0.5)枚(4～5,n=4),卵的大小为(14.0±0.4)mm×(11.2±0.4)mm(n=17)。育雏期为(13.8±0.5)d(13～14,n=4)。孵化期内雌鸟日活动期的平均长度为(833.2±40.0)min,平均每天离巢(46.6±12.2)次(n=27),每次离巢时间为(5.3±2.8)min(n=1435),每次在巢时间为(12.7±7.5)min(n=1409),在巢率为72.4%±11.6%(n=21)。雨天在巢和离巢的时间与晴天有显著差异,晴天在巢率为71.5%±12.1%(n=13),雨天在巢率为75.1%±9.0%(n=8)。在整个孵卵期间所有记录到的卵温平均为31.2℃(49066min内连续记录58879次)。雌鸟每次离巢,卵温平均下降(9.4±3.4)℃(n=1450)。     

广西防城港黑翅长脚鹬的繁殖行为

本研究于2021年3～9月,采用目标观察和全事件记录法,对广西防城港市钦州湾八路水湿地黑翅长脚鹬（Himantopus himantopus）的繁殖习性进行全过程观察记录。黑翅长脚鹬的栖息生境主要在盐田、虾塘和鱼塘,而巢主要分布在盐田生境。共发现39巢,雌雄共同营巢,按照主要巢材将其巢分为干草巢、碎石巢、泥皮巢和牛毛毡草巢4种;巢材包括禾本科（Gramineae）和莎草科（Cyperaceae）植物以及碎石、贝壳等;巢外径为（23.3±10.7）cm,巢内径为（11.2±1.9）cm,巢深为（1.6±0.5）cm,巢高为（6.5±4.3）cm(n=39);筑巢需（3±2）d(n=6)。窝卵数2～4枚,1～2 d产1枚卵,7 d内产完满窝卵（n=6）。雌雄均参与孵卵,雄性孵卵时间比雌性长,但二者差异不显著（P> 0.05）,雄性（8 550±245.9）min,雌性（7 530±263.3）min,孵卵期为（25±2）d(n=6)。育雏期（26±3）d(n=6),雌雄轮流育雏,育雏前、中期（雏鸟1～20d日龄）,雌性育雏时间比雄性长,是雄性的2倍,育雏后期（雏鸟大于20 d日龄）,...     

红碱淖遗鸥孵卵行为

2012年5-6月,应用e-Science信息技术,对红碱淖遗鸥的孵卵行为进行了研究.结果表明,不同孵化阶段昼夜间孵卵节律分别为:孵化前期换孵次数6.40±0.45(n=68)、2.37±0.20 (n=62),坐巢方向变换35.34±2.12(n=68)、16.16±0.67(n=62),翻卵次数10.81±0.50 (n=68)、6.58±0.40 (n=62);孵化中期换孵次数2.20±0.12 (n=66)、0.52±0.06 (n=60),坐巢方向变换18.73±0.85 (n=66)、4.28±0.31 (n=60),翻卵次数10.14±0.55 (n=66)、4.22±0.30 (n=60);孵化后期换孵次数1.81±0.10 (n=48)、0.53±0.07(n=47),坐巢方向变换15.17±0.75 (n=48)、3.87±0.34(n=47),翻卵次数8.65±0.51(n=48)、3.26±0.22(n=47).当大风或大雨时,对同一孵化阶段的换孵次数、坐巢方向变换和翻卵次数均存在极显著差异(P＜0.01).双亲交替换孵主要集中于04:00-06:00、08:00-10:00、12:00-14:00等时间段内.孵化后期,亲鸟坐巢时长达到601.14±31.16 min (n=56).遗鸥通过调节昼夜间的孵卵节律来控制卵的温度,以保证昼夜间卵胚胎的正常发育.     

陕西红碱淖棕头鸥孵卵行为

2014年5—6月,应用e-Science信息技术,对红碱淖棕头鸥的孵卵行为进行了研究。结果表明,不同孵化阶段昼夜间孵卵节律分别为:孵化前期换孵次数7.88±1.08(n=39)、5.00±0.89(n=39),坐巢方向变换27.75±2.04(n=39)、14.37±1.72(n=39),翻卵次数27.13±2.02(n=39)、11.25±1.08(n=39);孵化中期换孵次数3.11±0.19(n=65)、1.32±0.11(n=65),坐巢方向变换23.37±0.91(n=65)、10.95±0.86(n=65),翻卵次数21.11±1.11(n=65)、8.47±0.77(n=65);孵化后期换孵次数3.17±0.22(n=42)、0.95±0.05(n=42),坐巢方向变换20.06±1.46(n=42)、6.62±0.84(n=42),翻卵次数22.39±1.78(n=42)、5.33±0.55(n=42)。当大风或大雨时,对同一孵化阶段的换孵次数、坐巢方向变换和翻卵次数均存在极显著差异(P0.01)。双亲交替换孵主要集中于04:00—10:00、12:00—14:00等时间段内。孵化后期,亲鸟坐巢时长达到(713.29±40.62)min(n=42)。棕头鸥通过调节昼夜间的孵卵节律来控制卵的温度,以保证昼夜间卵胚胎的正常发育。同时与同域分布繁殖的遗鸥的孵卵节律进行了比较。     

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.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.