云南纳帕海湿地越冬斑头雁活动区

活动区范围反映了动物在个体水平上的空间需求,开展相关研究对物种保护以及理解动物与环境之间的关系具有重要意义。于2017、2018和2019年共3个越冬季,在云南纳帕海湿地对7只斑头雁（Anser indicus）进行了卫星遥测,运用动态布朗桥模型构建了斑头雁越冬期活动区,并结合遥感技术分析了水域面积变化对斑头雁活动区的影响。结果表明：所跟踪斑头雁的总活动区域中有54.7%位于保护区范围内,其余活动区域则分布于保护区外围的草地或沼泽中;斑头雁越冬期的平均活动区面积和核心活动区面积分别为（5.98 ± 0.63）km2和（0.55 ± 0.12）km2（n = 8,2017年越冬季1只个体数据、2018年越冬季6只个体数据和2019年越冬季1只个体数据）,核心活动区面积仅占活动区面积的9.2%;最大活动区面积为8.22 km2,最小仅为3.38 km2,最大核心活动区面积为1.21 km2,最小为0.12 km2;斑头雁活动区面积受纳帕海湿地水域面积变化影响较大,随着水域由南向北退缩,沼泽及草甸增多,斑头雁的活动范围变大,且会向着水域退减的方向移动;2639号斑头雁在2018年和2019年两年越冬季相同时间段的活动区面积和分布均存在显著差异,2018年越冬季活动区的面积（5.98 km2）小于2019年（8.22 km2）,核心活动区的面积（0.61 km2）同样也小于2019年（1.21 km2）,并且其两年越冬季活动区面积的重叠度指数IO仅为0.31。鉴于斑头雁是H5N1高致病性禽流感的重要携带者和传播者,建议保护区增加保护区管理范围,对与斑头雁活动区重合较大的村庄,包括云南省迪庆州香格里拉市建塘镇的开松、纳公和打日觉等重点管理,避免家猪与斑头雁混群觅食,倡导在冬季时对家猪进行圈养,防止可能引起的禽流感交叉传播。     

河南陕西两地白冠长尾雉的集群行为

20 0 1年 4月至 2 0 0 3年 6月 ,在河南董寨国家级自然保护区和陕西佛坪县瓦寨子对白冠长尾雉 (Syr maticusreevesii)的集群行为进行了研究。对 17只遥测个体的跟踪结果和 32 8次集群活动的野外记录分析表明 ,白冠长尾雉雌雄两性的集群方式有极显著的差异 ( χ2 =18 177,df=3,P =0 0 0 0 )。雄鸟有很强的领域性 ,优势个体全年以单独活动或双雄共同活动的方式占据稳定的活动区 ,很少与其他雄性个体集群 ;雌鸟有很强的集群倾向 ,除繁殖季节因孵卵、育雏而离开群体单独活动外 ,通常以 4～ 6只的群体游荡于雄性个体的活动区之间 ,与该活动区的雄鸟形成不稳定的混合群 ,偶尔与其他群体形成暂时性的、更大的混合群。两性集群方式的差异可能与其各自经受的捕食压力和交配竞争强度 (雄 >雌 )差异有关     

白冠长尾雉雄鸟的冬季活动区与栖息地利用研究

2001年和2002年冬季,利用无线电遥测技术在河南董寨国家级自然保护区内对白冠长尾雉(Syrmaticusreevesii)雄鸟的冬季活动区和栖息地利用进行了研究。对遥测位点超过30个的5只雄性个体的研究表明,白冠长尾雉雄鸟的冬季活动区面积为10.03±1.17hm2(最小凸多边形法,MCP)、8.60±0.35hm2(90%调和平均转换法,90%HMT)和9.50±1.90hm2(95%固定核法,95%FK),明显小于其繁殖期的活动区面积。核心区面积为1.88±0.37hm2。核心区的栖息地组成在个体间变化较大,但主要是针阔混交林、松林、杉木林和灌丛。在研究区尺度上,白冠长尾雉雄鸟对栖息地有明显的选择性,但在活动区内则是随机利用栖息地。乔木胸径、灌木高度、2.0m层盖度及灌丛与森林的距离对雄性白冠长尾雉冬季的栖息地选择有重要影响。根据本项研究结果,我们建议在白冠长尾雉的栖息地管理中首先应加强对现存栖息地的保护,同时应通过适当的造林来扩大栖息地面积,此外还要注意对大面积的现有灌丛进行改造。     

青海湖棕头鸥(Larus brunnicephalus)夏秋季活动区研究

2006年4～9月,采用无线电遥测技术对青海湖重要繁殖水鸟棕头鸥(Larus brunnicephalus)在不同繁殖阶段的活动性,以及与人和鸟的关系进行了研究.对6只棕头鸥个体的遥测结果表明,繁殖初期棕头鸥的活动区较大,进入繁殖中期,活动区明显变小;随后繁殖后期的活动区面积有所增加,到了迁徙前期,活动区面积已接近繁殖初期.不同阶段活动区核心面积(50%Fixed Kernel)与活动区变化趋势基本一致.繁殖初期、中期、后期和迁徙前期活动区面积分别为(15.48 km2±4.54 km2)、(1.61 km2±0.41 km2)、(3.53 km2±2.63 km2)和(11.61 km2±9.36 km2).棕头鸥在不同繁殖阶段的日活动区大小有显著差异.繁殖初期,棕头鸥经常活动于鸬鹚岛、蛋岛和布哈河口,它们都是棕头鸥较好的取食地,鸬鹚岛和蛋岛由于有许多游客投喂食物;在繁殖中期,棕头鸥进入孵化阶段,活动区较繁殖前期明显缩小.由于湟鱼返回布哈河口一带产卵繁殖,棕头鸥经常聚集在此地取食;在繁殖后期,棕头鸥需要寻找大量的食物进行育雏,因此活动范围再度扩大;进入迁徙前期,幼鸟已经长大并学会飞翔,其活动区进一步扩大,与繁殖初期较为接近.     

黑顶麻雀的活动区及其影响因素

2017和2018年每年6至10月,在甘肃安西极旱荒漠国家级自然保护区利用无线电遥测技术对繁殖期16只黑顶麻雀(Passer ammodendri)(9♀,7♂)和繁殖期后1个月内雌雄各1只的活动区进行了监测。使用95%固定核空间法(FK)计算活动区面积,60%固定核空间法求得的活动区面积作为核心区面积。结果显示,在繁殖期雌雄黑顶麻雀个体间的平均活动区面积分别为(23.88±4.50)hm²(n=9)和(32.36±7.24)hm²(n=7),核心区面积分别为(3.92±0.70)hm²和(5.55±1.55)hm²,繁殖期雌雄个体间的活动区和核心区面积均无显著差异。繁殖结束后一个月内雌雄活动区面积分别为123.86hm²和272.40 hm²,核心区面积分别为23.68 hm²和64.88 hm²。雌、雄性个体繁殖期的活动区面积和核心区面积均显著小于繁殖期后。个性表现为羞怯的个体活动区面积显著小于个性表现为勇敢...     

山地次生林冬季鸟类集群的初步研究

通过山地次生林两冬季鸟类集群的研究表明,集群的鸟类主要是由大山雀、沼泽山雀和普通Ｓｈｉ组成;每群个体数为７．４１－１０．６３只;据群的行为（单种群、多种集群和单独个体）分析,大多数种类是单独个体活动,冬季鸟类集群大小和组成有空间的变化。气候因子影响群的形成和行为。     

雉鸡的冬季集群行为观察

有关雉鸡 (Ｐｈａｓｉａｕｎｓｃｏｌｃｈｉｃｕｓ)冬季集群行为研究 ,Ｗｅｓｔｅｒｋｏｕ (1 956)在新西兰发现大多数雉鸡不集群 ;而Ｒｉｄｌｅｙ (1 983 )则认为雉鸡不仅在冬季集群 ,且群体是由同一性别的个体所组成。王建平等[3]报道 ,在山西庞泉沟国家级自然保护区观察 ,雉鸡在冬季有明显的集群行为 ,且有性别隔离现象。于1 997～ 1 999年的 1 0～ 1 2月和 1 998～ 2 0 0 0年的 1～ 2月 ,我们在山西历山国家级自然保护区对雉鸡冬季的集群行为进行了研究 ,现将有关资料报告如下。1　工作区自然概况历山国家级自然保护区位于本省中条山东…     

繁殖期白冠长尾雉占区雄鸟的活动区

20 0 0年 3～ 8月采用无线电遥测技术对董寨国家级自然保护区的白冠长尾雉 (Syrmaticusreevesii)繁殖期占区雄鸟的活动区进行了研究。对遥测时间超过 6 0天的 7只个体的研究表明 ,繁殖期白冠长尾雉占区雄鸟对活动区具有较强的依恋性 ;90 %调和平均转换法 ( 90 %HMT)计算的繁殖期活动区大小为 46 0± 13 7hm2 (n=7) ;繁殖初期、中期和末期的活动区大小分别为 2 4 5± 6 3、 19 6± 7 5和 17 9± 6 2hm2 (n =7) ;随着繁殖期的结束活动区与日活动区呈减小趋势。白冠长尾雉占区雄鸟对活动区的 3个亚区 (夜栖区、觅食休憩区和过渡区 )的利用时间存在明显差异 ,活动区所在地的植被结构的不同可能是造成这种差异的主要原因.     

朱鹮繁殖期的活动区和栖息地利用

20 0 0～ 2 0 0 2年 ,我们应用标记识别法和地理信息系统对朱繁殖期的活动性、活动区和栖息地利用进行了研究。结果表明 :朱在越冬期、繁殖期和繁殖后期的觅食距离存在差异 ,分别为 2 82 1± 1 4 88km、0 5 6 3± 0 6 81km和 1 70 6± 0 834km ,但同一时期中不同个体间的觅食距离无显著差异。不同年份中 ,朱在越冬期和繁殖期的觅食距离无显著差异 ;在繁殖后期 ,由于受到干旱等气候因素的影响 ,两年的觅食距离差异显著。一天中觅食距离最远的是 10 :0 0～ 12 :0 0 ,最近的是 0 6 :0 0～ 0 8:0 0。不同时间段中觅食行为的比例差异显著 ,0 6 :0 0～ 10 :0 0和 16 :0 0～ 18:0 0为取食高峰期 ,中午和夜宿前的休息和理羽行为则高于其他时间段。MCP法和 90 %Kernel法的计算结果表明 ,其中 8只观测次数较多的朱在繁殖期的平均活动区面积分别为10 0 8± 4 9 8hm2 和 175 6± 91 3hm2 ,5 0 %Kernel法计算的活动区的核心面积为 4 3 8± 2 1 5hm2 。朱个体间的繁殖活动区重叠强度较大 ,达到各自活动区的 2 4 5 %± 2 7 3%。朱营巢比较密集 ,配对亲鸟间的活动区重叠强度和其他个体的重叠强度无显著差别。栖息地利用研究表明 ,朱对针阔混交林的利用率显著低于研究区内的可利用率 ,对水田的利用     

四川栗子坪自然保护区红腹角雉雌鸟和亚成体冬季集群行为研究

2005年11月至2006年3月,在四川省石棉县栗子坪省级自然保护区对低海拔区域(海拔1800²400 m)红腹角雉Tragopan temminckii雌鸟和亚成体冬季集群行为进行了调查。结果表明:红腹角雉的雌鸟和亚成体以单独活动的个体居多,占44.4%,其它依次为3只群、2只群和4只群。群体的规模较小,最大群体为4只。在集群类型上,家族群可能是主要集群类型,但还有待验证。红腹角雉雌鸟和亚成体集群的个体和单独活动个体在取食行为的时间分配上有显著差异,集群的个体用于取食的时间比例要高于单独活动的个体。在警戒、休息和移动行为时间分配上没有显著差异,但单独活动个体用于警戒的时间比例要高于集群的个体。本研究的结果验证了动物集群的反捕食假说,集群活动的个体有更多的取食时间。     

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.