江西桃红岭自然保护区夏季梅花鹿对生境的选择性

2005年6-8月在江西桃红岭自然保护区对夏季梅花鹿的生境选择性进行了初步研究。结果表明：梅花鹿选择灌丛和灌草丛、郁闭度较低、灌木盖度较小、食物丰富度高、阴坡、中上坡位、坡度平缓、水源距离在100-400m、人为干扰距离〉800m和海拔高度〉300m的环境;对郁闭度〉80％和水源距离≤100m的环境表现为随机选择。     

清凉峰自然保护区梅花鹿秋季对栖息地利用的初步分析

20 0 3年 9～ 1 1月 ,作者在浙江省清凉峰自然保护区 ,对梅花鹿栖息地的利用进行了研究 ,选择 9类生态因子 ,并设置 3 89个 1 0m× 1 0m样方。选择指数的结果表明 ,梅花鹿喜欢选择草甸 沼泽和灌丛、郁闭度较低、食物丰富度高、上坡位、海拔≥ 1 2 0 0m、人为干扰距离 >1 0 0 0m、向阳、坡度平缓的生境。分析表明 ,梅花鹿对灌木盖度的选择以适合为准。主成份分析表明 ,影响梅花鹿栖息地选择的主要因子有 4种 ,依次为 :干扰因子 (包括海拔、坡位和人为干扰距离 )、食物因子 (包括郁闭度、食物丰富度和植被型 )、灌木盖度因子和地形因子 (包括坡度和坡向 )。     

浙江清凉峰国家级自然保护区华南梅花鹿栖息地适宜性评价

理解环境因子对物种空间分布的影响,评价栖息地适宜性现状并预测潜在分布区,对野生动物的管理和保护具有重要意义。华南梅花鹿（Cervus pseudaxis）属国家I级重点保护野生动物,现仅分布于安徽、浙江、江西等狭小片区内。浙江清凉峰自然保护区千顷塘区域是华南梅花鹿的重要分布区,但其面积较小,严重限制了华南梅花鹿的种群发展,亟需对千顷塘及周边区域的栖息地质量进行评价,为华南梅花鹿的保护和野外放归提供科学依据。本研究利用红外相机监测千顷塘区域华南梅花鹿的分布,结合遥感等技术手段获得地形、植被、水源以及人为干扰等8种环境因子,利用MaxEnt构建华南梅花鹿栖息地适宜性模型,对以千顷塘为中心50 km×50 km的范围进行栖息地适宜性评价。研究结果表明,华南梅花鹿倾向于选择海拔1050-1240 m范围内,距道路100-900 m和距人口聚居区3200-3800 m的相对平缓地带。千顷塘区域华南梅花鹿栖息地保护较好,适宜栖息地面积为2224 hm2,占该区域39.1%。千顷塘周边适宜性较高的区域主要为位于其西南部约10 km的山区,该区域为华南梅花鹿提供了3253 hm2的潜在适宜栖息地。建议降低保护区千顷塘区域内的人为干扰,并在其西南部山区尝试开展圈养种群的野外放归工作,以促进其种群发展。     

华南梅花鹿声音通讯行为的初步研究

2005年3～12月,在江西桃红岭自然保护区对华南梅花鹿的声音通讯行为进行了初步研究,得到4种特点较为分明的梅花鹿叫声类型,即警戒叫声、求偶叫声、呼唤叫声和团体合唱声,并对这4类叫声的生物学意义进行了初步分析.     

森林采伐对桃红岭国家级自然保护区梅花鹿冬季生境选择的影响

2011年和2012年的冬季在桃红岭国家级自然保护区采用随机样方法,调查了森林采伐对梅花鹿冬季生境选择的影响。调查结果表明:梅花鹿冬季在采伐迹地和非采伐区生境选择存在显著性差异。在采伐迹地,梅花鹿多在植被密度适中或稠密、覆盖度适中或较高、海拔200 m以上的生境活动;在非采伐区,梅花鹿多在植被高度低于1 m、植被密度适中、海拔400 m以上的生境活动。森林采伐后第3年梅花鹿的活动利用强度最大。     

华南梅花鹿主雄的社会行为初步研究

2005年3～12月,在江西桃红岭自然保护区对华南梅花鹿主雄的社会行为进行了初步研究,记录了主雄等级序位的建立与维持、声音通讯、领域性、争雌打斗、交配和护群等6类社会行为,并对这些行为的生物学意义进行了初步分析.     

大雾岭保护区穿山甲冬季生境选择

1999年12月至2001年2月,对大雾岭自然保护区穿山甲冬季栖息地的选择进行了研究,结果表明对林型选择的先后次序为针阔混交林、灌木丛、常绿阔叶林、针叶林;最偏爱针阔混交林,最不喜爱针叶林.多选择陡坡(30～ 60°);干扰源距离较远(>1 000 m),干扰程度小;林下草灌层盖度高(81% ～ 100%),隐蔽程度好; 阳坡或半阴半阳坡;中低海拔(760 ～ 1 500 m);中下坡位;水源距离较近(<500 m);乔木郁闭度适中(31% ～ 70%)的生境.较少选择上坡位,林下草灌层中低(0 ～ 50%),乔木郁闭度偏高(71%～ 100%)或偏低(0～ 30%),阴坡的生境.对洞口设置的要求是多朝南,而且要求隐蔽条件好,多数为全隐蔽或半隐蔽;最不喜爱将洞口设置在裸露、隐蔽程度差的生境,强力避免洞口向北.坡度、干扰源距离和林下草灌层盖度是影响穿山甲冬季栖息地选择的关键环境因子.     

四川铁布梅花鹿自然保护区梅花鹿夏季栖息地选择

四川梅花鹿Cervus nippon sichuanicus为国家Ⅰ级重点保护动物,四川铁布梅花鹿自然保护区分布有我国现存最大的梅花鹿野生种群。2011年6-9月,采用样方法对保护区梅花鹿夏季栖息地选择进行了调查,共布设109个样方(利用样方61个,对照样方48个),测量并比较了海拔、坡度等20个生境因子。结果显示,梅花鹿偏好利用的植被类型为灌丛、草甸、针叶林,同时选择隐蔽度较高的生境;此外,距水源距离、灌木高度、灌木盖度、灌木密度、草本高度和草本盖度6个连续变量在利用样方和对照样方之间差异有统计学意义(F<0.05或U<0.05)。回归模型分析结果表明,梅花鹿夏季偏好选择草本盖度大、靠近水源和林缘的生境,回避远离水源和林缘的生境。     

白冠长尾雉越冬期栖息地选择的多尺度分析

2000年至2002年冬季,在河南董寨国家级自然保护区对我国特有珍稀雉类白冠长尾雉（Syrmaticus reevesii）越冬期栖息地进行了调查,并结合RS和GIS在多个尺度上对其栖息地选择进行了分析.结果表明,不同尺度上影响白冠长尾雉越冬期栖息地选择的因素存在差异,影响因子之间还存在相互作用.在微生境上,影响因子主要是坡度、乔木盖度以及坡向余弦值与灌木高度的相互作用;在115 m尺度上,关键因子是灌木林、阔叶林和针叶林的面积;250m尺度上,主要因子是针叶林和阔叶林的面积及针叶林与阔叶林面积的相互作用;对于距离因素,到河漫滩和到农田的距离是影响白冠长尾雉越冬期栖息地选择的关键因子.根据回归分析和AIC及AICc值,115 m尺度上栖息地变量对白冠长尾雉越冬期的栖息地选择影响最大.综合分析发现,在较大的尺度上,影响白冠长尾雉越冬期栖息地选择的关键因子有针叶林面积、阔叶林面积、针叶林和灌丛面积的相互作用、到河漫滩的距离以及到农田的距离.     

河南董寨白冠长尾雉繁殖期栖息地选择

2001年至2003年春季,采用样线调查和媒鸟招引,在河南董寨国家级自然保护区对我国特有珍稀雉类白冠长尾雉（Syrmaticus reevesii）的栖息地选择进行了调查,结合RS和GIS分析了在景观水平上对栖息地的选择性,并借助逐步逻辑斯谛回归分析了影响繁殖期白冠长尾雉栖息地的关键尺度和主要因素。结果表明,在白云保护站,占区雄性白冠长尾雉在不同栖息地类型中的出现频率不同,出现最多的是混交林,其次是杉木林,随后是松林、灌丛、阔叶林;在董寨自然保护区内,在115 m尺度和250 m尺度上,针叶林的面积比例均是影响其栖息地选择的关键因子,而到农田的距离是距离因素中最重要的因素。根据回归分析和AIC_C及ΔAIC_C值,115 m尺度上栖息地变量对白冠长尾雉繁殖期的栖息地选择影响最大。综合分析表明,影响白冠长尾雉繁殖期栖息地选择的主要因子为115 m尺度上针叶林的面积比例和到农田的距离。建议在制定白冠长尾雉栖息地保护策略时,应加强现有适宜栖息地的管理,改善栖息地布局,并从景观尺度上开展针叶林对白冠长尾雉种群影响方面的研究工作。     

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.