Mathematical Formulations for the Height/Weight Tables of U.K. Children after Tanner,Whitehouse and Takaishi

Models of human height and weight growth and their interrelations are applied to the height/weight tables for British children given by Tanner, Whitehouse and Takaishi (1966) in two elaborate papers. Approximations using nonlinear regressions yield very satisfying results for height/age and log weight/height relations as well as the velocities of height and weight. Graphs with the basic data and the approximated growth curves are added.     

庐山蕨类植物区系研究

庐山共有蕨类植物39科87属247种(含变种、变型),其区系带有热带和温带双重性。其中鳞毛蕨科、水龙骨科、蹄盖蕨科、金星蕨科和铁角蕨科属种优势明显,共有38属160种,分别占总属数的43.7%和种数的64.8%,代表了该地区蕨类植物区系的一个重要特征。该区区系地理成分复杂,相互交错,其中热带性属占总属数的64.2%,温带性属占总属数的35.8%。东亚成分在该区系占有绝对优势,共有14属,占总属数的20.9%,中国特有属缺乏,特有种丰富,表明成分具有多样性并具有热带亲缘性,是亚热带向北温带的过渡地区。该区与井冈山、武夷山关系密切,与鼎湖山、秦岭和横断山关系疏远。     

Peroxidase Isozymes from Meloidogyne spp. and Their Origin

Two peroxidase isozymes (Ef 0.43 and 0.53) were detected by electrophoretic analysis in homogenates of Meloidogyne arenaria, M. hapla, M. javanica, and M. incognita females reared on tomato. No peroxidase isozymes were detected electrophoretically in homogenates of adult males, preparasitic larvae, or eggs. Peroxidase isozymes from females reared on bean, eggplant, or tobacco differed from those from females reared on tomato. Bean and eggplant populations had a single peroxidase isozyme each, respectively Ef 0.21 and 0.28. No peroxidase isozymes were detected in tobacco populations under the conditions used, although total activity assays did reveal low levels of peroxidase activity in homogenates of tobacco populations. The peroxidase isozymes detected in females reared on tomato or bean appear similar to the peroxidase isozymes present in root-knot galls, adjacent ungalled roots, and roots from uninoculated plants of the corresponding hosts. The probability is discussed that most of the peroxittase activity associated with Meloidogyne spp. females is of host origin.     

PV技术的计算机处理及其在树木水分关系研究中的应用

ＰＶ技术的计算机处理及其在树木水分关系研究中的应用刘建伟,刘雅荣,王世绩（中国林业科学研究院林业研究所,北京１０００９１）ＣｏｍｐｕｔｅｒＰｒｏｃｅｓｓｉｎｇｏｆＰＶＣｕｒｖｅＡｎａｌｙｓｉｓａｎｄＩｔｓＡｐｐｌｉｃａｔｉｏｎｉｎｔｈｅＲｅｓｅａｒｃ...     

Influence of Plant-Parasitic Nematodes on Longleaf Pine Seedlings

Seedlings of longleaf pine (Pinus palustris) were grown in 20-cm pots for 5 to 7 months in the greenhouse following inoculation with a high or low level of one of seven species of plant-parasitic nematodes. Belonolaimus longicaudatus and Helicotylenchus dihystera had no effect on seedling growth. High inoculum densities of Hoplolaimus galeatus and Tylenchorhynchus claytoni caused a significant reduction of fresh weight of seedling roots. Root and top weights of seedlings grown in soil infested with Meloidodera floridensis or Pratylenchus brachyurus were significantly less than those of seedlings in noninfested soil. Root growth of seedlings was stimulated by the higher inoculum density of Scutellonema brachyurum.     

Early Pleistocene Equus (Equidae,Perissodactyla) from Andersson Loc. 32 in Qixian,Shanxi, China

The Equus specimens of Andersson Loc. 32 in Qixian, Shanxi previously identified as Equus cf. sanmeniensis are rediscovered in this research. The skull has moderate size, deep nasal notch, clear preorbital fossa, undulated lateral outline, upper cheek tooth with simple fossette and incisor with incomplete cup, should be identified as Equus teilhardi. The mandible has cheek tooth with V-shaped linguaflexid, incisor with incomplete cup, moderate size, strong pli caballinid and deep ectoflexid on molar, should be identified as Equus qingyangensis. This skull is first record of a complete cranial material of E. teilhardi, reveals many important cranial features of E. teilhardi, supports anatomical comparison and phylogenetic discussion with other stenonid horses. The morphological differences between E. teilhardi and E. qingyangensis show their different niches, further explain the reason of their coexistence. Incomplete cup on incisor is an unstable feature. It has been found in several species of stenonid horses, likely a remaining feature derived from the most primitive Equus, Equus simplicidens. The small-sized stenonid horses with short limbs and incisors with incomplete cups likely have relation with E. teilhardi, such as Equus yunnanensis and Equus stehlini. E. qingyangensis has most primitive features in Eurasian stenonid horses.     

稻田节肢动物群落的营养联系

根据田间调查和室内饲养观察的资料,研究了稻田节肢动物群落的营养结构及类型。在稻田生态系统中,物种之间由于取食与被取食、寄生与被寄生、捕食与被捕食的营养联系,形成了复杂的食物链和食物网。依据物种在食物网中的位置和功能,可将福州市郊区稻田节肢动物群落的营养结构分为3种类型:1)食物网中尚未发现有重寄生环节;2)食物网中有重寄生环节;3)食物网中有兼寄生环节。为了探讨定量研究生物群落营养联系的可能性,本文运用图论的知识把食物网的结构描述为标向图、集合或邻接矩阵,同时用图论的运算法则解决了各种类型的食物网的合并问题,为研究复杂群落的营养关系提供了一种新方法。     

科尔沁沙地丘间低地樟子松人工林水分利用来源的稳定同位素解析

20世纪50年代以来,樟子松(Pinus sylvestris var.mongolica在中国北方干旱半干旱地区沙地广泛引种.近年来一些早期引种的樟子松人工林出现了早衰现象.分析生境水分条件变化、判断樟子松采取何种水分利用策略对于认识其早衰现象很有裨益.因此,本研究利用稳定同位素示踪技术,研究了科尔沁沙地东南缘固定沙丘丘间低地30年生樟子松人工林的水分来源及其利用的季节动态,分析了降水和土壤水分变化对樟子松水分利用的影响,阐明了樟子松与伴生植物(黄柳Salix gordeieril)在水分来源方面的异同.结果表明,樟子松及其主要伴生植物黄柳枝条水的稳定18O同位素组成(δ18O)存在明显的季节变化;樟子松的水分来源主要来自20～ 40 cm或更深土层;樟子松和主要伴生植物黄柳之间存在明显的水分竞争,后者比樟子松先行利用最近较强降水(如降水量＞10 mm),从而影响樟子松水源的补给.本研究对于揭示沙地樟子松衰退与水分利用策略的关系具有重要意义.     

The number of species occurring in a sample of a biotic community and its connections with species-abundance relationship and spatial distribution

Connections among species-abundance (i-m _i ), species-frequency (i-F _i ), and species-sample size (S _n -n) relationships were examined on the basis of the mapping data of a natural forest in Thailand. The spatial distribution of individual trees without any discrimination of species was nearly random. Provided that the spatial distribution of each species was random, thei-m _i and thei-F _i relationship was reconstructed from each other in terms of the total number of species (S) and the total number of individuals (N) in the data. The number of species (S _n ) in a subsample consisting ofn individuals was then obtained from thei-F _i relationship. Logarithm ofS _n increased with logn and showed a convex curve through the origin. The values of diversity indices based onN andS(orn andS _n ) were affected by sample size. These trends were further examined on the basis of 944 data sets of biotic communities and three mathematical models of anS-N relationship. The properties of species-area relation were discussed in the light of these results.     

High pH in the nutrient solution impairs water uptake in Lupinus angustifolius L.

Root growth in Lupinus angustifolius is greatly decreased when the nutrient solution has a pH above 6.0. This study examined the water relations in this species (cv. Yandee) in response to high pH in solution culture in a glasshouse.The dry weight of roots, the length of taproots and lateral roots and the number of lateral roots were significantly reduced at day 12 after transfer to solution with a pH of 7.5 compared to pH 5.2. This resulted in a marked reduction of total root surface area. However, shoot growth and total leaf area were not affected. In comparison with pH 5.2, plants grown at pH 7.5 in the nutrient solution had a 14–38% more-negative leaf water potential, and their stomatal resistance had increased by 67%.The observations indicate that the impairment of the water relations by high pH is mainly caused by decreased root growth.     

Probing the Transition State of the Allosteric Pathway of the Shaker Kv Channel Pore by Linear Free-Energy Relations

Long-range coupling between distant functional elements of proteins may rely on allosteric communication trajectories lying along the protein structure, as described in the case of the Shaker voltage-activated potassium (Kv) channel model allosteric system. Communication between the distant Kv channel activation and slow inactivation pore gates was suggested to be mediated by a network of local pairwise and higher-order interactions among the functionally unique residues that constitute the allosteric trajectory. The mechanism by which conformational changes propagate along the Kv channel allosteric trajectory to achieve pore opening, however, remains unclear. Such conformational changes may propagate in either a concerted or a sequential manner during the reaction coordinate of channel opening. Residue-level structural information on the transition state of channel gating is required to discriminate between these possibilities. Here, we combine patch-clamp electrophysiology recordings of Kv channel gating and analysis using linear free-energy relations, focusing on a select set of residues spanning the allosteric trajectory of the Kv channel pore. We show that all allosteric trajectory residues tested exhibit an open-like conformation in the transition state of channel opening, implying that coupling interactions occur along the trajectory break in a concerted manner upon moving from the closed to the open state. Energetic coupling between the Kv channel gates thus occurs in a concerted fashion in both the spatial and the temporal dimensions, strengthening the notion that such trajectories correspond to pathways of mechanical deformation along which conformational changes propagate.     

步氏巨猿犬齿与前臼齿咬合关系的观察

步氏巨猿的上犬齿与下第一前臼齿的咬合关系有两种主要类型:一是相似于“猿类”的,另一相似于“人类”的。前者为雄性个体所具有,后者为雌性个体所具有。另有少数个体的则是中间类型。上犬齿与下第一前臼齿的咬合特征的分类学上的意义是可疑的。至少就绝大部分雄性步氏巨猿个体来说,很难认为其犬齿是参与臼齿的功能。步氏巨猿下第一前臼齿之所以呈双尖类型,与其犬齿并无直接的关系。     

峡谷暖区柑桔气候生态的定量研究

作为山地气候[7,8] 类型之一的峡谷地形气候 ,在农业上的应用研究已引起广泛的关注。研究其农业地形气候[10 ] ,特别是对作物气候生态进行定量研究 ,有助于峡谷区域农业气候资源的合理开发与利用。本文所述及的峡谷主要是指鄂西南的长江三峡、清江河谷及香溪河谷。因峡谷地形特别 ,气候的突出特征是峡谷暖区 (因海拔 80 0ｍ附近的冬季气温接近于同纬度的江汉平原而可定为暖区的上限 )的形成 ,其表现为隆冬少有低温冻害 ;难有积雪、雨凇和雾凇 ;风力弱、无偏北大风 ;有效辐射小、净辐射量大。其成因为 :冷空气难进易出 ;西南暖槽的保护作用[2…     

A new method for determining the relation between soil- and plant-cadmium

On soils differing in total Cd concentration, organic matter content and pH, but with the same compost treatment, a significant linear relation was found between the calculated Cd²⁺ concentration of the soil solution and the Cd concentration of lettuce grown under field conditions. The Cd²⁺ concentration was calculated with the equation for the exchange reaction between Cd²⁺ and Ca²⁺.     

曼地亚红豆杉蒸腾速率日变化及因子分析

应用LI-1600 稳态气孔计对曼地亚红豆杉(Taxus media cv.Hicksii)叶片的蒸腾速率、气孔阻力和几个生态因子的日变化同步进行了测定。并采用多元回归分析和灰色关联度分析的方法探讨了曼地亚红豆杉叶片蒸腾速率与影响因子的关系, 结果表明:影响曼地亚红豆杉蒸腾速率的主要因子是叶温、气温;其次是光量子通量密度、空气相对湿度、气孔阻力。灰色关联度分析与多元回归分析结论基本一致。对曼地亚红豆杉叶片蒸腾速率与气孔阻力的相关关系分析表明:蒸腾速率和气孔阻力间属非线性关系, 其方程为:Tr=12.789-13.419 lg Rs(R²=0.971 7)     

肾性高血压大鼠肥大心肌的力速关系和收缩末期张力长度关系

左肾动脉部分狭窄造成大鼠肾血管性高血压,研究高血压四周肥大心肌的力速关系,收缩末期张力长度关系(ESTLR)以及对细胞外高钙的反应。结果表明:(1)肥大心肌主动峰张力 PT 轻度增大,零负荷最大缩短速度 V_(max)明显减小,收缩时程 TPT 延长(P<0.01),力速曲线向下移位;(2)高血压组心肌 ESTLR 与对照相似,亦为非线性的指数曲线。回归参数a(总张力)、k(静息张力)、b(曲线曲率)和 L。(最大缩短程度)均无明显改变(P>0.05),(3)高钙灌流时,肥大心肌的反应(△PT,△V_(max)和△TPT)与对照间无显著差异(P>0.05)。上述结果提示:高血压心肌肥大早期基础力学性能的变化以力速分离现象为特征,此时心肌功能的异常可能与肌膜钙转运系统的功能状态无关;对于心肌收缩能力的这种慢性改变,心肌力学指标比 ESTLR 类参数更敏感。     

前自交型小红花寄生种子特性及寄生关系的建立

寄生是生物有机体之间一种常见的互作关系,其有趣的生理、生态和进化问题日益受到关注与研究。以小红花寄生(Scurrula parasitica var. graciliflora)为研究对象,研究了该植物的开花物候、繁育系统、种子萌发特性及寄生关系的建立。结果表明:小红花寄生的开花高峰期为4月中下旬至5月下旬。花冠筒闭合期间与花冠筒开裂24 h后的花粉活力均 90%,且两者之间没有显著差异(P0.05),但花冠筒开裂48 h之后的花粉活力≤70%。柱头可授性在花冠筒闭合期间显著高于花冠开裂之后(P0.05)。自然授粉的对照组和花蕾期套袋的实验组的座果率(分别是82.5%和83.1%)显著高于花开放之后的异花授粉的实验组的座果率(33.8%)(P0.05),而去除雄蕊的花则未能结实。小红花寄生的种子对脱水敏感,严重脱水显著降低种子萌发率。适宜的种子萌发温度为25℃和30/20℃。仅在桂花幼树的茎顶叶腋处获得了6.25%的寄生成功率,而其他部位的人工寄生均不成功。综合分析表明,两性花的小红花寄生依赖于前自交型的自花授粉;种子萌发表现出明显的温度偏好性,但对光照没有依赖性。人工寄生成功率显示,种子依附的寄主部位直接影响小红花寄生的幼苗与寄主寄生关系的建立。