40种散生竹的染色体数目

报道中国9属40种散生竹类染色体数目,其中31种为首次报道。     

六种中国苔类植物的染色体数目

报道了6种中国苔类植物配子体茎尖分生组织有丝分裂中期的染色体数目(1)皱叶耳叶苔,n=9;(2)双齿异萼苔,n=9;(3)卵叶羽苔,n=9;(4)丛生光萼苔日本变种,n=8;(5)密叶光萼苔,n=8;(6)格氏合叶苔,n=9。其中丛生光萼苔日本变种的染色体数目为首次报道,双齿异萼苔的染色体数目为国内首次报道。     

部分散生竹类染色体数目

本文报道了中国74种竹的染色体数目,其中65种为首次报道。     

贵州产蜘蛛抱蛋属植物的细胞分类学研究

报道了6种贵州产蜘蛛抱蛋属植物的染色体数目和核型,并与其相应近缘种对比,联系植物的外部形态特征,探讨核型结构与形态特征的相关性.发现1个种的染色体数目为2n =36,5个种的染色体数目为2n =38,核型公式分别为:平塘蜘蛛抱蛋(Aspidistra pingtangensis),2n =38 =20m +4sm(2sat) +14st;荔波蜘蛛抱蛋(A.liboensis),2n =38 =22m(2sat)+4sm+ 12st;赤水蜘蛛抱蛋(A.chishuiensis),2n =38 =22m(2sat)+8sm +8st;伞柱蜘蛛抱蛋(A.fungilliformis),2n =36=18m (2sat) +4sm+ 14st;四川蜘蛛抱蛋(A.sichuanensis),2n =38 =22m (2sat) +4sm +12st;丛生蜘蛛抱蛋(A caespitosa),2n =38 =20m +6sm(2sat) +12st.核型类型都为2C型.其中平塘蜘蛛抱蛋、荔波蜘蛛抱蛋和赤水蜘蛛抱蛋的染色体数目和核型均为首次报道.研究结果表明,该属植物的核型结构与外部形态特征具有一定的相关性,细胞分类学研究可以为该属植物起源进化研究以及自然分类鉴定提供一定的依据.     

十种贵州产苔类植物染色体数目

报道了贵州产 1 0种苔类植物染色体数目。它们是护蒴苔Calypogeiafissa,n =9,全缘广萼苔Chan donanthusbirmensis,n=9,尖瓣褶叶苔Diplophyllumapiculatum ,n =8,刺齿合叶苔Scapaniaciliata ,n =9,格氏合叶苔S .griffithii,n=9,羽枝羽苔Plagiochilafruticosa,n =8,延叶羽苔P .semidecurrens,n =8,尖叶扁萼苔Radulakojana ,n =7,丛生光萼苔Porellacaespitans,n=8,塔柱大光耳叶苔Frullaniataradakensi,n =9。其中尖瓣褶叶苔 ,格氏合叶苔 ,塔柱大光耳叶苔的染色体数目为首次报道     

杭子梢属10种植物的染色体数目

本文报道了杭子梢属Campylotropis Bunge国产10种1变种的染色体数目,其小孢子染色体数目为n=11,体细胞染色体数目为2n=22。 在光果小雀花C．polyantha var．leiocarpa中发现有少数个体为2n=23的非整倍体。     

国产香茶菜属十三个分类群的细胞学研究

对国产11种2变种共16个居群的香茶菜属植物的染色体数目进行了研究。除线纹香茶菜细花变种以外,其它种类的染色体数目均为首次报道。研究结果表明,有12个物种为二倍体,其染色体数目均为2n=24,推测该属植物的染色体基数为x=12。而细锥香茶菜既有染色体数目为2n=24的居群,也存在2n=48的居群,表明该种为二倍体或四倍体,同时2n=48的染色体数目也是香茶菜属内的首次报道。     

国产6种铁线莲的染色体研究

本文报道了我国产铁线莲属Clematis L.6个种的染色体研究结果。其中2种(灌木铁线莲和粗柄铁线莲)的染色体数目及核型为首次报道,1种(女萎)为国内首次报道。6种均为二倍体(2n=2x=16),基数为8(x=8)。本属基数为8的二倍体核型公式概括如下: 2n=2x=16=10m+2st+(4或2或0)st[(2或0)SAT]+(0或2或4)t[(2或4)SAT]核型特征是:中型(4—10.5μm);1—5号为m染色体,6号为st染色体,7—8号染色体变异于st和t之间;具1或2对随体(SAT)染色体。该属染色体的演化处于两种水平:数目变化(包括多倍化和非整倍体变化)和结构变异。后者是本属物种形成的主要方面。3种具异形同源染色体,这种杂合性可能是缺失所致。     

两种国产苏铁属植物的核型分析

报道了苏铁属（Cycas L.）2种植物的染色体数目及其核型.它们的体细胞染色体数目均为2n=2x=22,核型均属3B型.核型公式分别是：海南苏铁C.hainanensis K（2n）=2x=22=4m＋2sm＋4st＋12T,仙湖苏铁C.szechuanensis subsp.fairylakea K（2n）=2x=22=2m＋4sm＋4st＋12T.两种苏铁的核型均为首次报道.支持基于染色体资料把苏铁属分为两个类群的观点.     

国产十四种苋属植物的染色体数目

报道了国产14种苋属植物的染色体数目。部分种的染色体数目为2n=34,即反枝苋Amaranthus retroflexus,刺苋A．spinosus,红苋A．cruentus,腋花苋A．roxburghianus,合被苋A．polygonoides,皱果苋A． viridis,凹头苋A．lividus,苋A．tricolor。其他种的染色体数目为2n=32,即尾穗苋A．caudatus,绿穗苋A． hybridus,千穗谷A．hypochendriacus,繁穗苋A．paniculatus,北美苋A．blitoides,白苋A．albus。其中腋花 苋的染色体数目为首次报道。该属染色体基数为x=16,17。两种染色体基数在苋属2个组(sect．Ama- ranthus和sect．Blitopsis)中均存在。由于苋属植物染色体大多为小型染色体,因此对苋属植物目前尚不 能进行详尽的核型分析。     

正廿面体病毒的三角形剖分数和壳粒数公式的推导

本文对p=h~2+hk+k~2,T=pf~2,C=10T+2和C=10p(n-1)~2+2几个公式进行了新的推导和计算,并对其公式间的关系和每个参数的数学含义作了说明,进而澄清了一些模糊认识,加深了对公式的理解和运用。     

6种1变种猕猴桃植物染色体数目的研究

报道了猕猴桃属６种１变种细胞染色体数目,表明湖北猕猴桃、激光猕猴桃、黄毛猕猴桃为二倍体,２ｎ＝２ｘ＝５８;大花猕猴桃为四倍体,２ｎ＝４ｘ－１１６,绿果猕猴桃（美味猕猴桃的１个变种）为种倍体,染色体数目２ｎ＝４ｘ－１１６,以上均为首次报道。并再次证实ｘ＝２９应是本属染色体数目的基础,狗枣猕猴桃和阔叶猕猴桃二倍体类型２＝５８。     

“x” is not a bias,but a number with real biological significance

Recent literature criticized the use of the symbol “x” to denote basic chromosome number in cytotaxonomy. I show here that this criticism is superfluous and is based on historical confusion between the concepts of basic chromosome number (or monoploid chromosome number), which is objective, and ancestral basic chromosome number, which is always inferred, by means of several – more or less reliable – methods. The most relevant literature is discussed and, in the end, I propose the use of x for basic chromosome number and p for (hypothetical) ancestral basic chromosome number.     

中国鲤形目鱼类的中轴骨骼数及其生态适应性

为探讨中国鲤形目鱼类中轴骨骼数及其与系统发育和生态习性的相关性,采用X光透视照相法对157种鲤科(Cyprinidae)、鳅科(Cobitidae)、平鳍鳅科(Balitoridae)鱼类的脊椎骨数、肋骨数、尾椎数进行了比较分析。结果显示,中国鲤形目鱼类的脊椎骨数在30-52枚之间,均值39.45?4.44;肋骨数在8-28对之间,均值15.27?3.08;尾椎数在14-34枚之间,均值21.08?2.89。依据脊椎骨数、肋骨数、尾椎数对鲤科各亚科进行聚类,显示鲤科12个亚科分为2大类：雅罗鱼类,包括雅罗鱼亚科、鲌亚科、鲴亚科、裂腹鱼亚科等4亚科;鲃类,包括鲢亚科、鮈亚科、鱼丹亚科、鲃亚科、野鲮亚科、鳅鮀亚科、鲤亚科、鱊亚科等8亚科。单因素方差分析显示,鲤科肉食性鱼类的肋骨数与脊椎骨数的比值显著少于植食性鱼类(P＜0.05),而脊椎骨数、尾椎数则显著多于植食性鱼类(P＜0.05)。中上层鱼类的脊椎骨数、尾椎数显著多于下层鱼类(P＜0.05)。极小型鱼类的脊椎骨数、肋骨数,以及肋骨数与脊椎骨数之比显著少于大型鱼类(P＜0.05)。表明鲤科鱼类的中轴骨骼数与其系统发育和生态习性及体型具有明显的相关性。     

Effect of an Artificial Caudal Fin on the Performance of a Biomimetic Fish Robot Propelled by Piezoelectric Actuators

This paper addresses the design of a biomimetic fish robot actuated by piezoeeramic actuators and the effect of artificial caudal fins on the fish robot＇s performance. The limited bending displacement produced by a lightweight piezocomposite actuator was amplified and transformed into a large tail beat motion by means of a linkage system. Caudal fins that mimic the shape of a mackerel fin were fabricated for the purpose of examining the effect of caudal fm characteristics on thrust production at an operating frequency range. The thickness distribution of a real mackerel＇s fin was measured and used to design artificial caudal fins. The thrust performance of the biomimetic fish robot propelled by fins of various thicknesses was examined in terms of the Strouhal number, the Froude number, the Reynolds number, and the power consumption. For the same fm area and aspect ratio, an artificial caudal fin with a distributed thickness shows the best forward speed and the least power consumption.     

中国产3种防己科植物细胞学研究

报道了3种国产防己科植物的染色体数目。金线吊乌龟Stephania cepharantha Hayata为二倍体2n=22,部分居群的一些个体存在B染色体;轮环藤Cyclea racemosa Oliv．为二倍体2n=24;木防己CDcculus orbiculatus(L)DC为四倍体2n=4x=52.3个种的染色体基数分别为x=11,12,13。观察了木防己的小孢子母细胞减数分裂过程,其减数分裂过程正常,且花粉粒具较高活性。     

Chromosome numbers of some caespitose bamboos native in or introduced to China

This paper reports chromosome numbers of 94 species in 13 genera of caespitose bamboos native in or introduced to China. The chromosome numbers of 74 species are roported here for the first time. The original basic number of bamboos is considered to be x = 8. Chromosome numbers ofmost of the caespitose bamboos are found to be 2n = 70 ± 2.     

A mathematical model for malaria involving differential susceptibility,exposedness and infectivity of human host

The main purpose of this article is to formulate a deterministic mathematical model for the transmission of malaria that considers two host types in the human population. The first type is called “non-immune” comprising all humans who have never acquired immunity against malaria and the second type is called “semi-immune”. Non-immune are divided into susceptible, exposed and infectious and semi-immune are divided into susceptible, exposed, infectious and immune. We obtain an explicit formula for the reproductive number, R ₀ which is a function of the weight of the transmission semi-immune-mosquito-semi-immune, R _0a , and the weight of the transmission non-immune-mosquito-non-immune, R _0e . Then, we study the existence of endemic equilibria by using bifurcation analysis. We give a simple criterion when R ₀ crosses one for forward and backward bifurcation. We explore the possibility of a control for malaria through a specific sub-group such as non-immune or semi-immune or mosquitoes.     

‘Single lay out’ and ‘mixed lay out’ enzymatic processes for bio-bleaching of kraft pulp

Xylanase alone as ‘single lay out’ (strategy I) and in combination with pectinase as ‘mixed lay out’ (strategy II) was used to investigate their bio-bleaching potentials. Strategy I was carried at 70 °C using 5 U/g of xylanase at pH 9.5 and 12.5 whereas strategy II was carried out at 70 °C using 5 U/g of each of the enzyme, respectively at pH 9.5. Bio-bleaching caused 15% and 20% less Cl₂ consumption though strategy I and II, respectively over chemical bleaching. Strategy II was proved to be 35.71% more efficient in ClO₂ saving than conventional method. Significant improvement in various pulp properties viz. tensile strength 25.70%, breaking length 21.80%, burst factor 20.00%, burstness 13.86%, tear factor 6.61% and tearness 18.88%, was also observed through ‘mixed lay out’ strategy.