赤水河上游云南光唇鱼年龄与生长研究

2007年10月至2008年5月间在赤水河国家级鱼类保护区上游的云南镇雄县坡头乡采集到云南光唇鱼(Acrossocheilus yunanellsis)430尾(体长范围57mm～281mm),其中雄鱼77尾,雌鱼97尾,其余的性别不确定,样本为流刺网和电击捕获.通过鳞片对430号标本进行了年龄鉴定,首次对赤水河上游云南光唇鱼的年龄与生长特点进行了研究,分析了体长、体重、鳞径的关系及渔获物的年龄结构组成.所采集云南光唇鱼的年龄由0-5龄组成;体长与鳞径呈线性正相关关系,关系式为: L♀=0.0157R-0.0043 (r2=0.9146);L♂=0.164R-0.0919(r2=0.8445);体长与体重呈指数关系,关系式为:W♀=0.000032L2.89004(r2=0.9788);W♀=0.000021L2.9764(r2=0.9808).     

西伯利亚鲟稚幼鱼生长特征的初步研究

在人工培育条件下,对西伯利亚鲟稚幼鱼的生长特征进行了研究,结果表明:平均体长为2.12 cm、平均体重为0.07 g的7日龄稚鱼经140 d的人工饲养长成平均全长为42.69 cm、平均体重为254 g的个体,其日均增长量2.93 mm、平均瞬时增长率2.14 %,全长与日龄之间呈线性关系,L = -0.7711+ 0.3126t (r = 0.9948);体重日均增长量1.82 g、平均瞬时增重率5.37 %,体重与日龄呈指数函数关系,W = 0.3157e0.0529t (r = 0.9354);体重与全长的回归曲线为W = 0.0082L2.7046 (r = 0.9977),幂指数值接近3,表明该鱼体重与全长的立方呈正相关关系,属于等比生长类型。     

凤鲚瓯江种群的生物学特性

2006年5—8月对浙南瓯江凤鲚的繁殖期生物学特性进行了调查和研究．结果表明,凤鲚瓯江种群汛期雌雄个体体重（W）与体长（L）的关系分别为Wf=0．021 Lf^2.52（R^2=0．77）和Wm=0．0127 Lm^2.605（R^2=0．72）．个体绝对繁殖力在2836—62901粒之间,平均为（21112±8919）粒;绝对繁殖力（r）与体长（L）、体重（W）和纯重（NW）均呈线性正相关．相对繁殖力（r／L）与体长、体重呈线性正相关,平均个体相对繁殖力（r／L）为（1146±398）粒／cm;相对繁殖力（HW）与体长、体重无关,平均个体相对繁殖力（HW）为（657±186）粒/g．     

蛇鮈个体生殖力的研究

蛇鮈绝对生殖力为4770（1476-14730）粒，相对生殖力（F/L）为393.3（113.5-978.1）粒/cm.F/Wu为326.6（71.0-651.0）粒/g。鱼体长范围为9.6-16.1cm，体重范围为8.9-52.4g，绝对生殖力和体长（L），净体重（W0）均呈直线正相关。     

微机在研究泥鳅生长特点中的应用

本文对泥鳅的生长特点进行了研究。在研究方法上,主要将所获得的样本数据,运用数理统计中回归分析;应用计算机软件,并在微机(APPLE—Ⅱ)上调式运行,对泥鳅的生长规律作了较为详细的探讨。结果说明,对泥鳅的体长、体重。纯体重的近期预测值,拟运用方程组(Ⅰ_1)估算;特别是体长估计用L_t=23.64(1-e~(-0.227(t+0.8583))的误差较小,而对泥鳅的生长状态的理论分析,运用方程组(Ⅳ_1)描述较能反映泥鳅的生长规律。泥鳅体长与鳞片长的关系为线性关系,方程式为:L=2.916+0.12835。S相关系数为:R=0.78035>r_(0.01)。泥鳅体重(W)、纯体重(W_c)与体长的关系分别为W=0.018472L~(2.6934),相关系数R=0.9396>r_(0.01);W_c=0.02009L~(2 6193),相关系数R=0.9397>r_(0.01)。依据扩充的Von Bertalanffy生长方程可求出体长生长曲线拐点,t_L=0.2434年,体重生长曲线拐点tw=5.4336年;亦为纯体重生长曲线拐点。而由变形的Von Bertalanffy生长方程,可求导出无体长生长曲线拐点,而体重生长曲线拐点tw=3.6889年,纯体要生长曲线拐点twc=3.8669年。 测试证明,同龄期的雄鳅纯体重大于雌鳅纯体重,且4龄期为泥鳅的最佳生长状态,主要是长肉。     

花鳗鲡形态性状数理分析与解剖

采用生物学常规测定法、解剖法和生物统计法,对30尾从黑仔阶段开始养40个月的花鳗鲡进行主要形态性状的测定及内脏解剖观察。结果表明：花鳗鲡的D-A/D- 头后缘=1.465±0.028;体长与其它形态性状的相关程度依次为：D-A>体宽>头长>D-头后缘>体高>眼间距;体长与体重的关系为W=1.76×10-3L3.11;肠近中部有一“V ”型小弯曲; 生殖腺肉眼见不到,出现时间明显晚于日本鳗鲡和欧洲鳗鲡。     

赤水河上游墨头鱼年龄与生长研究

对赤水河上游国家级鱼类保护区内的墨头鱼标本进行了年龄鉴定,渔获物的年龄结构由0～8龄共9个龄组组成,以低龄个体为主,2～5龄个体占83.07%。体长和体质量呈幂函数关系且幂指数接近3,属于匀速生长类型,因此用Von Bertalanffy方程描述其生长特性,相关生长参数分别为:渐近体长L∞=323.0227mm,渐近体质量W∞=824.7102g,k=0.1781,t0=-1.4655龄。体质量生长拐点年龄Ti=4.77龄,对应体长、体质量分别为Lt=333.14mm,Wt=746.06g。由于捕获物中以低龄个体为主,呈现小型化趋势,建议将其捕捞年龄确定为5龄以保护核心区内的墨头鱼资源。     

长吻龄群组成和生长特性研究

长吻是长江河流中有较高经济价值的鲶形目鲍科鱼类,共收集肥料325尾,全部材料均通过生物学测定。1989年采用IBM/AX计算机运用Von Bertalanffy鱼类生长方程的BASIC程序进行了重新整理运算。结果表明:龄群有1—6龄组,2—3龄鱼为渔获物的主要成份,占总尾数的54.27％,体长和体重的相关关系式为:W=2.221344×10~(-2)L~(2.828766)。生长曲线,生长速度曲线、生长加速度曲线反映出长吻鮠属均匀生长型,生长的拐点年龄为6.1龄,地外,体长、体重、吻长、全长、体国之间还进行了多元回归。     

迅速求解电功率难题的一个通用方法

电功率求解问题历来是中考的热点问题 ,也是难点问题之一 .本文拟从电源电压和电阻这两个常规不变量出发 ,以电源电压为主线推导与题设物理量相关的算式 ;再由这样的几个算式作方程组消元处理 ,得到各电阻间的关系式 ,从而使问题快速获解 .例 1　把灯泡L1接在电压不变的电源上 ,它消耗的功率为 4 5W .现将L1与灯泡L2串联后仍接入原电路 ,L2 的实际功率为1 0W ,且比L1的实际功率小 .此时L1的实际功率为　　　W .解 :L1的功率为 4 5W时 ,由P =U2R ,有U2 =4 5R1.①两灯串联时 ,由P =I2 R =UR总2 R ,有U2 =R2总RP .于是 ,对L2 有U2 …     

蛇鮈个体生殖力的研究

蛇绝对生殖力为4770（1476～14730）粒，相对生殖力（F/L）为393．3（113．5～978．1）粒／cm，F/Wo为326．6（71．0～651.0）粒／g，鱼体长范围为9．6～16．1cm，体重范围为8．9～52．4g，绝对生殖力和体长（L），净体重（Wo）均呈直线正相关。     

比体和赋体：象征性诗歌意象研究

象征性诗歌是以意象暗示、呈现象征意义的。其意象的构成方式主要有两种：一种是以意象与意象间具有的比喻关系构成的,即比体象征;一种是以意象的连续的铺展、延伸构成的,即赋体象征。这两种象征意象在诸多方面都存在着不同,弄清它们的构成方式及其特点,将有助于我们的诗歌创作和诗歌鉴赏。     

人体中的软骨

软骨是人和脊椎动物特有的胚胎性骨骼，由软骨组织及其周围的软骨膜构成。其中软骨组织是由软骨细胞、基质和纤维构成，根据软骨组织所含纤维的不同，软骨可分为透明软骨、纤维软骨和弹性软骨三种。     

肥胖与减肥

随着物质生活水平的提高,人群中肥胖者越来越多。肥胖不仅影响形体美观,而且严重危害身心健康,因此肥胖作为现代文明的副产物日益受到关注。     

The relations among body image, physical attractiveness, and body mass in adolescence

Body dissatisfaction, a measure of body image, physical attractiveness, and body mass index were assessed in the same 115 participants at ages 13, 15, and 18 years. Sex differences in body dissatisfaction emerged between 13 and 15 years of age and were maintained at 18. Over adolescence, girls increased, while boys decreased, their body dissatisfaction. Body dissatisfaction was weakly related to others' ratings of the adolescents' physical attractiveness and their body mass index. The results support the idea that, overall, adolescents' body image has little to do with how others perceive them, but once developed remains constant through much of adolescence.     

镁元素与人体健康

1人体中镁的存在 镁是人体必需的常量元素,是细胞内的主要阳离子,浓集于线粒体中,仅次于钾和磷.在细胞外液,镁仅次于钠和钙而居于第三位.成人体内镁总量约为20～28 g.其中70%以上参与骨骼和牙齿的组成,约25%存在于软组织中.     

The body bites back!

How should we think about the body in science education? What ought it mean to be alive and live within epistemologies and pedagogies? What does it mean to be human in science education? In response to Auli Arvola Orlander and Per-Olof Wickram’s article, this essay explores some of the possibilities and questions that the body evokes in science education research and practice. Drawing on selected theorizing in science education, environmental education and science and technology studies, the author suggests that we should strive to be more in tune with the seemingly mundane corporeal aspects of our performances and representations. This shift in attention has the potential to open up research, policy and practice agendas associated with relationships between pedagogies and embodied and disembodied knowledge and knowing. Such agendas might start by considering situated and embodied emotions in science education.     

Cultural practices of the Zulu ethnic group on the body and their influence on body donation

Cultural practices in the African continent have been thought to impact negatively on body donation. Thus, most African countries continue to rely on unclaimed bodies for dissection programs, or bequests from the white population. The latter situation is dominant in South African medical schools. Since South Africa is multi-cultural with nine main ethnic groups of the Black African population, it is important to seek the reasons behind lack of participation in body donation. This report represents a move in this direction with its qualitative study of the cultural practices of the Zulu ethnic group in the province of KwaZulu-Natal from the perspective of a variety of participants, with emphasis on their treatment of the human body after death. Four themes emerged from interviews: (1) Death is not the end; (2) Effect of belief in ancestors; (3) Significance of rituals and customs carried out on human tissue; and (4) Burial as the only method of body disposal. Each of these themes is discussed in relation to the likelihood of body donation being seen by Zulus as an acceptable practice. It is concluded that this is unlikely, on account of the need to preserve the linkage between the physical human body and the spirit of the deceased person, and the perceived ongoing relationship between the spirit of the dead and the living. In view of these conclusions, a number of options are canvassed about the manner in which anatomists in KwaZulu-Natal might obtain bodies for dissection. These possibilities have implications for anatomists working in comparable cultural contexts.