广西防城发现黄嘴白鹭的繁殖种群

20 0 2年 3～ 8月 ,在广西防城万鹤山首次发现国家Ⅱ级重点保护动物黄嘴白鹭的繁殖种群 ,约 4巢 ,8只成鸟 1 4只雏鸟。黄嘴白鹭于该年 3月底 4月初迁来筑巢繁殖。巢材多为常绿、落叶阔叶树枯枝和松枝。窝卵数 4枚 ,卵为淡蓝青色。雌雄鸟轮流交替孵卵 ,孵化期 2 4 5 0± 1 5 0 ( 2 3～ 2 6)d ,孵化率1 0 0 %。育雏期 41± 2 ( 3 9～ 43 )d ,窝雏数 3 5 0± 0 2 9( 3～ 4)只 ,雏鸟成活率 87 5 0 %。食性主要为鱼( 77 84% )、虾 ( 1 6 76% )和青蛙 ( 5 40 % )。     

新疆木垒波斑鸨营巢成功率的初步研究

1998年 4月中旬～ 7月中旬 ,对分布于新疆木垒的波斑鸨 (Chlamydotisundulatamacqueenii)种群的营巢成功率进行了初步考察与研究。考察中共发现 16个巢、2 5窝幼雏。每巢产卵 3～ 6枚 ,卵鲜重 (6 4 7± 5 8)g ,卵径为 6 0 9mm× 43 9mm。产卵有两个高峰期 ,表明雌鸟第 1次繁殖失败后可再次产卵。第 1产卵期的巢卵数为(4 1± 0 8)枚 ,第 2产卵期的巢卵数为 (3 5± 0 6 )枚。雌鸟营巢成功率为 77 5 %～ 87 5 % ,卵的孵化率为83 6 %。每窝内从破壳到具备飞行能力的幼雏数基本不变 ,表明繁殖雌鸟大都能将幼雏全部抚育到可以飞行的年龄     

南充金腰燕、家燕繁殖生态比较及易卵易雏实验

2004年3～10月对四川南充地区家燕、金腰燕的繁殖生态进行了观察,比较了其繁殖生态习性及雏鸟的生长特性,进行了家燕、金腰燕之间的易卵易雏实验.结果表明,家燕于2月中旬迁入南充,9月中旬开始迁离;金腰燕迁来较家燕晚,2月底～3月初迁入,9月中旬迁离.家燕于4月初产卵;金腰燕在4月上旬产卵.金腰燕卵的各项量衡度均较家燕的大,出壳时金腰燕雏鸟体重也比家燕雏鸟稍重.金腰燕雏鸟的体长、翅长、尾长、外部器官及体重的增长较家燕的快.而易卵、易雏的金腰燕雏鸟增长曲线则在金腰燕和家燕的雏鸟之间.易卵易雏的实验表明,在孵卵和育雏过程中,金腰燕与家燕之间彼此互换卵可以接受,易换雏鸟也可以接受.     

青海湖鸬鹚繁殖习性的初步观察

1999年 4～ 7月和 2 0 0 0年 3～ 8月 ,对青海湖地区的鸬鹚繁殖过程进行了观察 ,初步掌握了鸬鹚的迁移、营巢、产卵、孵卵、育雏和扩散等生态习性。结果表明 :鸬鹚每年 3月中、下旬迁来青海湖繁殖 ,两性共同营巢 ,营巢期集中在每年 4月上旬至 6月中旬 ;产卵高峰期为 4月下旬至 5月中旬。平均卵重是(5 7 5± 2 0 2 )g ,卵的大小为 67 2 9mm× 40 2mm ,平均窝卵数为 (3 61± 0 3 4)枚。鸬鹚孵卵期为 (2 8 0 7±0 5 3 )d ,孵化期间的卵重损失 (Y)与孵卵天数 (X)之间的线性回归方程为Y =0 997-0 0 0 68X(r=0 990 ,df=8,P <0 0 1 )。     

四川南充市区白腰文鸟的巢址选择与雏鸟的生长发育

20 0 2年 1 1月～ 2 0 0 4年 4月在四川省南充市区内对白腰文鸟 (Lonchurastriata)的繁殖习性进行了研究。结果表明 ,白腰文鸟 2月下旬开始繁殖 ;影响巢址选择的主要因素 9种 ;雌雄参与筑巢 ,营巢期 5～ 6d;雌雄轮流孵卵 ,孵卵期 1 3～ 1 5d ,整个种群的孵卵高峰期在 4～ 6月 ,窝卵数 (5 .61± 0 . 78) (n =1 8)枚 ,孵化率 86 0 7% ;雌雄均参与育雏 ,育雏期 1 8～ 2 1d ,雏离巢率 82 43 % ,繁殖生产力 3. 0 1 ,育雏两个高峰期 :上午 8:0 0～ 1 0 :0 0时和下午 1 6:0 0～ 1 8:0 0时 ,日育雏次数 (1 2 . 77± 6 .0 7) (n =3 4) ,育雏时间间隔(0 . 96± 0 . 42 )h(n =1 61 ) ;雏鸟形态生长曲线呈“S”型。     

哈尔滨家燕mandschurica亚种繁殖生态特征

许多鸟种因具有较强的适应性而分布广泛,例如家燕(Hirundo rustica)。在不同纬度地区研究其繁殖生态学特征有助于了解家燕对不同环境的适应。家燕mandschurica亚种在国内仅分布于黑龙江省,且该亚种的繁殖资料少有报道,为此,于2016和2017年每年的4至10月,在哈尔滨对其繁殖生态特征开展研究,并与国内目前已发表的家燕gutturalis亚种繁殖生态特征进行对比。家燕mandschurica亚种4月底或5月初迁来哈尔滨,9月下旬或10月初南迁;窝卵数为4～6枚(n=19);卵长径(18.7±1.4)mm(15.9～22.5 mm)、卵短径(13.0±0.5)mm(12.2～14.2 mm),卵重(1.6±0.1)g(1.3～1.9 g),n=35;孵卵期为(16±2)d(14～18 d,n=19);育雏期为(17±1)d(16～18 d,n=6)。雏鸟的体长、翅长及尾羽长的生长曲线能与Logistic较好地拟合;体重、嘴峰和跗跖在5日龄左右生长最快,体长和翅长在7日龄左右增长最快,雏鸟的生长模式符合能量分配假说。与我国南方的家燕gutturalis亚种相比,在哈尔滨繁殖的mandschurica亚种的卵更小、更轻,二者孵卵期相似,但后者育雏期更短。这或许与不同地区食物丰富度及亲鸟喂食策略有关。     

吉林省白城地区干草原栗斑腹的繁殖生态

栗斑腹在吉林省为留鸟 ,一年可繁殖两次 ,其雏鸟为典型的晚成鸟。 4月末开始有求偶追逐和争雌行为 ,5月中旬产卵。雌雄鸟筑巢时间分别是 43 min/d和 3 6min/d(筑巢第 4天 )。平均窝卵数为 5 .0 9± 0 .5 8枚 /巢 (n=3 1 ) ,孵卵前、中、后期雌鸟孵卵占白天活动时间的 3 5 %、74.5 %和 67.6% ,孵化期为 1 2 d,孵化率为 3 6.3 % ,2、8日龄喂雏分别为 4.5次 /h和 9.0次 /h。雏鸟的体重及外部器官的发育除嘴峰外 ,生长曲线均符合 Logistic方程 ,而嘴峰长的生长近似直线 ,栗斑腹雏鸟生长发育体重的生长模型为 :W =1 4.95 /1 +(e- 0 .552 ( t- 3.6 3) ) ,雏鸟 1 1日龄后出飞 ,繁殖成活率为 2 7.7%。     

厦门鸡屿岛白鹭几种繁殖活动的观察

于 2 0 0 1年 3～ 7月采用颜色标记法 ,记录厦门白鹭保护区内鸡屿岛白鹭 (Egrettagarzetta)卵产出和孵出的顺序和时间 ,并称重卵和雏鸟。有 91 4 %的窝卵数为 4～ 5枚 ,产卵期 7 0± 1 9d ,出壳期 4 2± 1 4d ;卵孵化时间与产卵顺序显著负相关 ;不同产出顺序卵重无差异 ;不同孵出顺序雏鸟早期 (≤ 5d)发育无差异 ,之后差异显著 ,第 4出壳的雏鸟发育水平和成活率较低 ,而第 5出壳的雏鸟最低 ;亲鸟在产卵期的孵化是非连续的 ,而产卵结束后相对连续。如此 ,可以调节孵化时间 ,进而调控异步孵化的程度 ,使雏鸟在生长阶段形成适当的等级差别 ,以获得最大的繁殖收益。     

陕西佛坪黑喉歌鸲的巢址特征和繁殖生态

2013年4～7月,采用样方法和直接观察法,在陕西佛坪分别对黑喉歌鸲的巢址特征和繁殖生态进行了初步研究。结果发现：黑喉歌鸲更倾向选择向阳、林冠稀疏、距水源较近的针阔混交林或针叶林下,秦岭箭竹丛林缘陡坡上的天然土洞内筑巢;巢口向上呈杯状,由竹叶、枯草、苔藓等编制而成,内无铺垫物。巢外底部垫有枯叶、干草等。巢外径长(100.37±4.00)mm,巢外径宽,(97.08±5.22)mm,巢高(48.18±2.24)mm。巢内径长(68.62±1.69)mm,巢内径宽(64.81±0.74)mm,巢深(36.07±0.30)mm。窝卵数(5±0.00)枚,卵重(1.91±0.05)g,卵长径(18.37±0.08)mm,卵短径(13.95±0.15)mm。孵化期12 d～13 d,孵化率为60%(n= 10),巢雏成活率为50%(n= 6),育雏期11 d。雏鸟的体重、体长的生长符合Logistic曲线方程拟合。天敌的捕食是影响黑喉歌鸲繁殖成功率的主要因素。关键词：黑喉歌鸲;繁殖生态;巢址特征;陕西佛坪     

有性棉蚜交配和产卵习性的观察

有性棉蚜有多次交配习性,交配时间平均为41分钟。雌蚜寿命为28．1±6．0天,产卵前期为3．0±1．2天,产卵历期为15．3±3．8天,产卵后期为9．7±3．4大,每雌产卵8．1±1．6粒,卵的产出率平均为88．4％。群体产卵的始盛、高峰和盛末期分别在羽化后3～4天、7～8天和15～16天。未经交配的雌蚜在产卵方面有明显的负效应,产出的受精卵也不能孵化。     

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.     

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     

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.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various