黑翅长脚鹬繁殖生态的研究

据黑翅长脚鹬繁殖生态的调查发现它的巢主要选择芦苇丛生的小土岛上,于5月末开始产卵,每窝卵4—5枚,卵重19.6;雌雄亲鸟均参加孵卵,孵化期17—19天。食物以鞘翅目昆虫,双翅目幼虫,半翅目的蚜虫等为食。此外还吃少量植物藻类。黑翅长脚鹬的天敌主要是猛禽和家犬,在繁殖期对卵和雏鸟危害较大,因此,在黑翅长脚鹬的繁殖期严禁放牧和捕鱼的生产活动,为黑翅长脚鹬的栖息与繁殖提供良好的环境条件。     

棕背黑头鸫繁殖习性初步观察

2008年和2009年的4～8月,在四川省雅江县帕姆岭对棕背黑头鸫Turdus kessleri的繁殖生态进行了初步观察.该鸟繁殖期在4月下旬至7月上旬,营树上巢,营巢树种为高山栎Quercus aquifolioides和鳞皮冷杉Abies squamata.窝卵数为2~3枚(n=7),平均卵重(7.96±0.03)g(n=8),卵长径(32.7±0.17)mm,短径(21.9±0.13)mm(n=13),雌雄共同孵卵,以雌性为主,孵化期为15~17 d(n=2),孵化率为83.3%(n=18).雌雄共同育雏,以雄性为主,雏鸟出飞后主要在巢周围的林下或灌从活动,这时亲鸟仍会对幼鸟喂食.在同一繁殖季对巢有重复利用的现象.     

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。     

湖北巴东寿带鸟繁殖行为观察

20 0 2年 5月～ 2 0 0 4年 8月 ,在湖北省巴东县沿渡河镇的东圩口、小溪、锯锯湾、两河口等 4个村 ,对寿带鸟 (Terpsiphoneparadisiincei)的繁殖生态进行了初步研究。研究结果显示 ,寿带鸟在湖北巴东的繁殖时间为 5月下旬～ 7月上旬 ,主要在农田居民区附近的阔叶树上营巢 ,巢材主要有青苔、草叶、草茎、细草根、棕丝、树耳、蜘蛛网等。筑巢工作主要由雌鸟承担 ,一般需要 5～ 7d即可完成。巢距离地面高度1 72～ 6 45m ,巢外径 6 0～ 8 8cm ,巢内径 4 9～ 6 4cm ,巢深 2 9～ 4 1cm ,巢高 6 3～ 9 5cm。雌鸟每天产 1枚卵 ,产卵时间均在清晨。窝卵数 4枚 (n =1 1 ) ,卵产齐后即开始孵化 ,雌雄鸟轮流孵卵 ,孵化期 1 3d。雏鸟晚成性 ,雌雄共同育雏 ,育雏期 9d。寿带鸟对不同的外界干扰反应明显不同 ,当有对其卵和雏鸟构成威胁的动物接近时 ,护巢行为表现十分强烈 ;而对其没有威胁的物种接近其巢时则无动于衷。面对同样的干扰 ,雌雄亲鸟的反应存在显著差异。     

湖北兴山红嘴相思鸟繁殖生态初报

2005年4月～2007年8月,在湖北省兴山县龙门河地区,对红嘴相思鸟(Leiothrix lutea)的繁殖生态进行了初步研究。研究结果显示,红嘴相思鸟在此地区的繁殖时间为4月中旬至7月下旬。巢多营于山坡上、山谷中的乔木林、灌木林遮蔽下的箬竹(Indocalamus wilsoni)和小灌木上,也营巢于农田边、山间小路旁、林间空地的箬竹丛或灌丛中。巢材主要有细树枝、细树根、细藤、箬竹叶、茅草叶、细草茎、青苔等。雌雄鸟共同筑巢,筑巢过程较为迅速,一般5～7d即可完成。雌鸟每天产一枚卵,产卵时间一般在清晨。窝卵数3.41±0.80(n=61)。孵卵期11～13d(n=6)。雏鸟晚成性,雌雄共同育雏,育雏期9～10d。雏鸟发育十分迅速,但离巢时身体发育尚未完善。红嘴相思鸟在此地区的繁殖成功率约为22.95%(n=61)。     

棕头鸦雀的巢生境因子分析和雏鸟的生长发育

2005年4~6月,在四川南充市西华师范大学新校区、西南石油学院和嘉陵江中坝区域内对棕头鸦雀(Paradoxornis webbianus)的繁殖行为进行了观察研究。结果表明,棕头鸦雀4月开始繁殖。影响巢址选择的生境因子主要有7种。雌雄鸟参与筑巢,营巢期5~6 d。窝卵数4~5枚(n=5)。雌雄鸟孵卵,孵卵期13~14 d。孵化率89.47%(n=4)。雌雄参与育雏,育雏期12~13 d。雏鸟离巢率88.24%(n=4)。雏鸟形态生长曲线呈“S”型。     

甘肃安西荒漠伯劳的繁殖生态

2010年4～8月在甘肃安西极旱荒漠国家级自然保护区,采用样点法对荒漠伯劳(Lanius isabellinus isabellinus)的繁殖生态进行了研究,采用单因素方差分析(ANVON)对荒漠伯劳卵体积与卵序之间的关系进行了研究,用二元Logistic回归对雏鸟生长曲线进行拟合。结果表明,荒漠伯劳的繁殖时间为4月底至8月初,每巢产卵3～6枚,平均窝卵数为4.67±0.57(n=21),卵体积为(3.14±0.32)cm3(n=95),卵鲜重(3.48±0.20)g(n=20),卵体积随着产卵顺序显著减小(R=-0.427,P=0.021,n=29),其采取的是"窝雏减少"的繁殖策略。雌鸟产首枚卵后即开始孵卵,雄鸟负责情饲及警戒。温度自动记录仪测量平均孵卵温度为(38.19±0.77)℃(n=2),雌鸟在巢率为93.95%。平均孵卵时间为(15.33±0.52)d(n=6)。荒漠伯劳雏鸟留巢期12～15 d,幼鸟离巢后亲鸟继续饲喂幼鸟,整个育雏期最长达31 d。研究地区荒漠伯劳种群的孵卵率为82.50%(n=80),卵成功率为46.25%(n=80),雏鸟离巢率为56.06%(n=66),巢成功率58.62%(n=29)。在2010年环志标记的12对繁殖鸟中只有1对繁殖了第二窝。     

四川南充地区白鶺鴒的繁殖习性

2004年2~5月在四川省南充市嘉陵江中上游的河漫滩内对白鶺鴒(Motacilla alba)的繁殖习性进行了研究。结果表明:白鶺鴒2月开始繁殖;雌雄参与筑巢,营巢期7~10 d;主要雌鸟孵卵,孵卵期13~14 d,上午8:00~9:00时孵卵出现一次高峰;窝卵数(5.00±0.52)(n=16)枚,孵化率42.5%;雌雄参与育雏,育雏期15~16 d,下午18:00~19:00时育雏出现一次高峰,日育雏次数(112.9±48.6)(n=17),育雏时间间隔(5.60±5.34)min(n=1 584);雏鸟形态生长曲线呈“S”型。     

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%)。     

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。     

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.