Physical, achievement and personality characteristics of Chinese children

The physical, achievement, and personality characteristics of Chinese schoolchildren are evaluated. The results of two surveys of Chinese schoolchildren, conducted in Beijing and Jilin Province, are presented. In the Beijing sample, the differences between only children and others were small but statistically significant, with the only children having higher scores in achievement and physical size. In the Jilin Province sample, the differences between only children and others were also small but significant. These differences were found entirely in physical characteristics, with only children being smaller, perhaps because the only children in the Jilin sample were much younger than the non-only children. Analyses of the combined sample of Beijing and Jilin schoolchildren indicated that the only-child advantages in achievement were found among children from urban families, not rural peasant families. While significant differences in height and weight were found in all three samples, none of the results indicated a significant difference in the proportion of body fat. None of the analyses indicated that only children had undesirable personalities, as judged by teachers and mothers.     

临高人的体质特征

应用《人体测量方法》调查了海南省临高成人417例(男211例,女206例)的71项体质指标,对18项体质指数进行计算,统计指数分型情况,并与我国部分族群体质资料进行比较,分析临高人的体质特征。结果显示:1)临高人头面部特征为圆头型、高头型、中头型、阔面型和中鼻型。临高人体部特征为中等型身材、中腿型、中胸型、宽肩型、中骨盆型、长躯干型。2)临高人以长躯干型、中腿型、宽肩型、中骨盆型、高头型、中头型、中鼻型出现率最高。3)临高人与海南其他族群比较头部、面部及五官部较宽,面部、鼻部高度值较小,身材宽而高。4)聚类分析显示,临高人体质特征与中国北方少数民族和其他地区汉族较接近。     

Physical characteristics of bone composite materials

To study the effects of varying mineral content and various trace elements in bone composities on its electrical behavior and possible use in design of transducers, various physical, dielectric, piezoelectric, and electromechanical parameters have been measured. For electrical characterization of various such composites in the high-frequency region (1–108 MHz), variation of impedance (Z), phase angle (tan ), and relative output voltage with frequency has been examined. Furtherfore, the Curie temperature has been determined and the temperature variation of capacitance and loss factor (tan ) studied (24–225°C). Two types of bone composites were prepared and studied. First, powdered collagen and apatite obtained from full bone were mixed intimately in various proportions by weight to prepare eleven bone compositions. Second, such bone materials were made to contain 5–10% various doping foreign additives (A1Br₃, Na₂CO₃, SrCO₃, LiCO₃, Sb₂O₃, ZnO, Nb₂O₅, piezoelectric ceramic (PZT), and Pb(NO₃)₂. It has been observed that a bone composition of 50% collagen + 50% apatite has possible piezoelectric application and other compositions [85% collagen + 15% apatite, 90% collagen + 10% ZnO, and 90% bone + 10% Ba(OH)₂] have a sharp rise in capacitance near the Curie temperature. The Curie temperature is generally shifted towards higher values by additives. It is expected that such results will be relevant in characterizing bone behavior.     

Physical characteristics in eucaryotic promoters.

For a series of wild type and mutated eucaryotic gene prelude sequences (mainly "promoters" of SV40 early gene (Benoist and Chambon, Nature 290, 304 (1981); Moreau et al., Nuc. Acids Res. 9, 6047 (1982)) and of Herpes Simplex Virus TK gene (McKnight and Kingsbury, Science 217, 316 (1982)), in vivo promoter activity and local stability (denaturability) have been correlated. In agreement with the conclusions drawn in these papers, the correlation points to three major eucaryotic promoter elements and loci: (i) enzyme enabling by an enhancer sequence; SV40 and Moloney Sarcoma Virus enhancers have a striking stability homology; (ii) enzyme activation, occurring 50-70 b.p. upstream the cap site in a high stability domain; the enzyme apparently deactivates exponentially upon moving away to trap site; (iii) enzyme positioning at trap site, 30 +/- 5 b.p. upstream the cap site. The trap site contains the TATA box, or, when absent, other low stability domains downstream the activator. The number and occupancy of cap sites may depend on the stability and size of the trap site-cap site couple and its distance from the activator.     

藏族的体质类型和人种学特征

藏族的体质类型和人种学特征一直受到学术界的关注。2018-2021年,我们测量了1530例卫藏、康巴和安多三个藏族人群的体质数据,统计结果发现,藏族男性、女性均为超中等身材,体质量超重,均为圆头型、高头型、中头型、中鼻型、中躯干型、宽胸型、宽肩型、宽骨盆型、中腿型,多有上眼睑皱褶,有内眦褶。对中国15个族群测量指标均数的主成分分析显示,藏族与东亚类型的汉族位点距离近于多数北亚类型族群,更近于多数南亚类型族群。藏族数据与国外资料中的东亚、南亚、北亚、北极类型数据的主成分分析结果显示,藏族与东亚类型位点最为接近。研究证实,当代藏族具有东亚蒙古人种类型的体质特征。     

Physical characteristics of mouse sperm nuclei.

The nuclei of epididymal sperm, isolated from C57BL/6J and CBA/J inbred mice by their resistance to trypsin digestion, retain the shape differences of the intact sperm head. Various physical characteristics of these nuclei were measured and compared. The measurement of the projected dimensions of nuclei showed that the CBA nuclei are 13.5% longer than C57BL/6 nuclei (8.64 +/- 0.02 mum compared with 7.61 +/- 0.02 mum), 0.8% narrower (3.51 +/- 0.01 vs. 3.54 +/-0.01 mum) with 6.8% more area (22.34 +/- 0.10 vs. 20.91 +/- 0.09 mum2). However, the volumes of the nuclei as based on reconstructing calibrated electronmicrographs of serial sections of the nuclei indicated that CBA are about 7% smaller than C57BL/6 nuclei (3.72 +/- 0.08 vs. 4.01 +/- 0.03 mum3). The buoyant density of the CBA nuclei is 1.435 +/- 0.002 g/cm3 compared with 1.433 +/- 0.002 g/cm3 for the C57BL/6 nuclei as determined on linear CsCl and Renografin-76 density gradients and confirmed by a technique utilizing physiological tonicities. Therefore, the average mass of the CBA nuclei is less than that of the C57BL/6 nuclei (5.34 +/- 0.12 vs. 5.75 +/- 0.05 pg). The sedimentation velocities at unit gravity of nuclei from 11 inbred strains differ over a range of more than 6% with CBA nuclei sedimenting about 2.0% more slowly than C57BL/6 nuclei. We show that for these nuclei the sedimentation velocity can be related to their buoyant density, volume and a sedimentation shape factor. Within the errors of our measurements of these various characteristics, it was found that C57BL/6 and CBA nuclei have similar sedimentation shape factors. Therefore, the difference in sedimentation velocity between these nuclei appears to be primarily a result of differences in volume. The possible applications of these techniques to the physical separation of sperm are evaluated in the discussion.     

崇义客家梯田生态系统服务功能

开展崇义客家梯田系统生态服务功能价值评估,有助于人们更好地了解梯田系统对崇义客家社会的重要贡献,为当地政府保护客家梯田系统提供重要依据.本研究基于崇义客家梯田系统及其所处区域的社会经济特征,构建了相应的生态服务功能价值评估指标体系;运用定性分析法对客家梯田系统的生态服务功能机理及其重要性作了识别;以2014年统计数据为基础,采用物质量和价值量相结合的定量评价方法,对客家梯田系统的9项生态服务指标进行评估.结果表明: 在评估的9项指标中,土壤保持的物质量和价值量同居各指标之首,分别为76457 kg·hm^-2和105033 元·hm^-2,相应地占梯田系统总物质量和总价质量的72.2%和30.0%.文化传承和景观体现了客家梯田系统独特的生态服务功能,价值量分别为100000和46333元·hm^-2,位居9项指标的2、3位.产品供给是客家梯田系统提供给崇义客家人的重要福祉,但其物质量和价值量只占梯田系统生态服务总物质量和总价值量的6.1%与10.4%,因此仅考虑产品供给将严重低估梯田系统的生态服务功能.直观的经济数字反映了客家梯田系统对社会的巨大贡献,不仅有利于提高管理者和公众保护农业文化遗产的意识,也为政府制定客家梯田系统生态补偿标准提供了数据支撑.     

Physical characteristics of 16 S rRNA under reconstitution conditions

The hydrodynamic shape and conformation of the 16 S ribosomal RNA in reconstitution buffer at both 4 degrees C and 37 degrees C were determined and compared with the corresponding properties of the 30 S ribosomal subunit at 4 degrees C in order to understand the role of the RNA molecule in the assembly of the 30 S subunit. At 4 degrees C, the 16 S rRNA has a sedimentation coefficient s020,w of 21.0 S, a diffusion coefficient D020,w of 1.72 X 10(-7) cm2/s, a frictional coefficient f/fmin of 2.37, and a hydrodynamic radius of 125 A. At 37 degrees C, the 16 S rRNA has a sedimentation coefficient s020,w of 18.4 S, a diffusion coefficient D020,w of 1.39 X 10(-7) cm2/s, a frictional coefficient f/fmin of 2.91, and a hydrodynamic radius of 153 A. At 4 degrees C, the 30 S subunit has a sedimentation coefficient s020,w of 31.8 S, a diffusion coefficient D020,w of 1.97 X 10(-7) cm2/s, a frictional coefficient f/fmin of 1.77, and a hydrodynamic radius of 109 A. These results suggested that the free RNA in solution at 4 degrees C is less folded than the RNA in the ribosomal subunit. At 37 degrees C, the free 16 S rRNA is unfolded when compared to the structure of the same RNA at 4 degrees C. This implies that the folding step accompanying the RI to RI transformation in the assembly process needs the presence of both the RNA and core proteins.     

Physical characteristics of the drumming of Meconema thalassinum

The drumming sound of Meconema thalassinum (De Geer) (Orthoptera: Tettigoniidae: Meconematinae) was studied in a North American population. Males of Meconema produce sound by tapping one of their hind feet on the substrate. Each phrase consists of a variable number (0–5) of short impact trains (mean, 5.6 foot impacts per train), followed by 1–5 long impact trains (mean, 34.4 impacts). The most common type of phrase consists of 3 short and 2 long trains.Foot impacts are produced at rates between 29 and 62/sec in the range 21.0–31.2°C. The foot-impact frequency follows a linear relationship with temperature; a similar relationship holds for the impact-train repetition rate, expressed as the reciprocal of the silent intervals between trains. The number of impacts per train and the overall phrase structure are essentially temperature-independent.The drumming of Meconema is compared with the sounds produced by other Orthoptera, in terms of temperature dependence and of complexity of the phrase structure.     

中国蒙古族的身高特征

研究目前中国蒙古族主要族群身高情况。对中国蒙古族共13个族群4410例（男43%,女57%）成人身高进行了测量,分析蒙古族身高分型情况,探讨不同年龄组之间、不同族群之间的身高变化趋势。中国蒙古族男性为超中等身材,女性为中等身材。在13个族群中,男性是额济纳土尔扈特部身高最高,云南蒙古族身材最矮。女性是鄂尔多斯部身材最高,云南蒙古族身材最矮。3个年龄组间身高差异均具有统计学意义。男性、女性都以高型出现率最高,过矮型出现率和很高型出现率都很低。中国蒙古族身高与中国其他北方族群接近,高于7个中国南方族群,低于北方汉族,但高于南方汉族,低于日本人、韩国人。中国蒙古族13个族群间身高差异均具有统计学意义,在中国族群中蒙古族属于身材较高的族群。     

Reproductive characteristics of Chinese Hu sheep

The reproductive characteristics of Chinese Hu sheep are reviewed. Male and female lambs reached puberty at a mean age of 120 days and 180 days, respectively, with an average body weight of 18.54 ± 1.48 kg (n = 31) and 22.75 ± 1.98 kg (n = 24). Adult male and female sheep reproduced throughout the year. On average, ewes lambed 1.65 times per year (n = 1482). The mean ovulation rate of adult ewes was over 2.2 (n = 46). The average litter size of 150863 ewes raised under extensive conditions was 2.06. The early sexual maturity of male and female lambs was respectively related to high concentrations of testosterone and 17β-E₂ in blood plasma in the earlier postnatal period. The mechanism of high fecundity is not known.     

Physical characteristics of ribosomal protein S4 from Escherichia coli

A hydrodynamic study of protein S4 from Escherichia coli 30 S ribosomal subunits indicates that this protein is moderately asymmetric. A sedimentation coefficient of 1.69 S and a diffusion coefficient of 7.58 X 10(-7) cm2/s suggest that S4 has an axial ratio of about 5:1 using a prolate ellipsoidal model. This structure should give a radius of gyration of about 29-30 A from small-angle neutron or small-angle x-ray scattering studies. This study has utilized quasi-elastic light scattering as an analytical tool to obtain a diffusion coefficient as well as a method to monitor sample quality. Using quasi-elastic light scattering in this manner allows an assessment of problems associated with protein purity which may be responsible for the many disparate results reported for ribosomal proteins and especially protein S4.     

Physical and chemical characteristics of apolipoprotein A-I-lipid complexes produced by Chinese hamster ovary cells transfected with the human apolipoprotein A-I gene

Chinese hamster ovary cells transfected with the human apolipoprotein A-I gene linked to the human metallothionein gene promoter region secrete large quantities of apolipoprotein A-I (7.1 +/- 0.4% total secreted protein) in the presence of zinc. Approx. 16% of the secreted apolipoprotein A-I is complexed with lipid and can be isolated ultracentrifugally at d less than or equal to 1.21 g/ml. The latter complexes are composed of discs and vesicles as judged by electron microscopy and can be further separated by column chromatography into three fractions: fraction I, mostly vesicles (60-260 nm) and large discs (18-20 nm diameter); fraction II, discs 14.2 +/- 2.6 nm diameter; and fraction III, nonresolvable by electron microscopy. The latter fraction is extremely lipid-poor (94% protein, 6% phospholipid); in contrast, the protein, phospholipid and unesterified cholesterol content for the other fractions are 43, 33 and 24%, respectively, for fraction I and 53, 33 and 14%, respectively, for fraction II. Fraction II particles contain three and four apolipoprotein A-Is per particle as determined by protein crosslinking while large structures in fraction I contain primarily six to seven apolipoprotein A-Is per particle. Following incubation with purified lecithin: cholesterol acyltransferase, discoidal particles were transformed into apparent spherical particles 12.9 +/- 3.4 nm diameter; this transformation coincided with 19-21% conversion of unesterified cholesterol to esterified cholesterol. The apolipoprotein A-I-lipid complexes isolated from Chinese hamster ovary cell media are similar to nascent HDL found in plasma of lecithin:cholesterol acyltransferase-deficient patients and those secreted by the human hepatoma line, Hep G2. The ability of the Chinese hamster ovary cell nascent HDL-like particles to undergo transformation in the presence of purified lecithin:cholesterol acyltransferase indicates that they are functional particles.     

Physical characteristics affecting the tensile failure properties of compact bone

Compact bone specimens from a wide variety of reptiles, birds, and mammals were tested in tension, and their failure properties related to mineral volume fraction, porosity and histological orientation. The principal findings were that the ultimate strain and the work under the stress-strain curve declined sharply with mineralisation, as did the stress and strain appearing after the specimen had yielded. Ultimate tensile strength was not simply related to any combination of the possible explanatory variables, but some relatively poorly mineralised bones, notably antlers, had high stresses at failure. These high strengths were allowed by a great increase in stress after the bones had yielded at quite low stresses.     

同域分布中华鬣羚与中华斑羚时空生态位特征

为了解同域分布有蹄类在环境复杂的山地森林生境中以何种方式维持种间关系以实现稳定共存,基于物种分布模型与日活动模式分析了四川省岷山、邛崃、大相岭、小相岭和凉山五大山系同域分布中华鬣羚(Capricornis milneedwardsii)与中华斑羚(Naemorhedus griseus)的时空生态位特征。结果显示:(1)在四川省五大山系,中华鬣羚的适宜栖息地面积为28006.07 km²,占研究区总面积的26.18%,其中高适宜栖息地面积为10015.90 km²,中华斑羚的适宜栖息地面积为21073.32 km²,占研究区总面积的19.71%,其中高适宜栖息地面积为8396.22 km²;(2)中华鬣羚与中华斑羚在生境因子选择上相似性高、栖息地重叠面积大,其空间生态位重叠度指数D=0.776,I=0.949,其适宜栖息地的主要重叠区域位于岷山和邛崃山系;(3)中华鬣羚与中华斑羚的日活动节律重叠指数为0.812;(4)中华鬣羚与中华斑羚属于同域分布的资源利用型竞争物种,中华鬣羚的存在会显著影响中华斑羚的日活动节律(P=0.016);二者同域分布时都会增加其昼间活动强度,并增加活动高峰期的强度及持续时间。本研究初步分析了中华鬣羚与中华斑羚的时空生态位特征,揭示了二者在空间、时间生态位上种群共存及种间竞争的耦合关系。研究有利于深入理解同域分布动物时空生态位特征、近缘物种的共存机制及种间竞争关系,为有蹄类等珍稀野生动物种群及栖息地的保护提供科学参考。