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K-L变换可消除样品各特征间的相关性,去除信息量较少或信息虚假的坐标轴,降低特征空间的维数,用较少量的特征描述样品,是目前最为有效的数据信息压缩抽取方法。利用K-L变换,样品之间变化较小的分类单元(目或功能群等),不会作为重要特征保留下来。因此,数量上占优势、或害虫防治中有重要地位的分类单元并不一定是识别样品的重要特征。可以藉K-L变换明确构成样品变异的主要分类单元,从而对不同地区、不同季节的取样实践有一定的指导意义、用通常的多样性指数分析及多样性差异显著性分析无法解决这个问题。用K-L变换可大大压缩数据存储空间。对数据量很大的生物多样性分析有较大的应用价值。反映样品所携信息量的热带水稻田无脊椎动物目主要是半翅目,中腹足目,以及表腹亚目。其中,在旱季半翅目占主要地位,而在雨季中腹足目占主要地位。就无脊椎动物目的组成而言,它们是构成样品变异的主要类群,是取样中需要得到特别注意的目。反映样品信息的无脊椎动物功能群主要是外部植食类,植食多食性类,半水生水面爬行类,粗粒残物取食类,以及陆生爬行、跳跃或猎者类,是取样中要重点考虑的一些类群。  相似文献   

3.
The long-awaited second edition of the International Symposium on "Epigenome Network, Development and Reprogramming of Germ Cells" hosted by Hiroyuki Sasaki took place at the Kyushu University School of Medicine, in Fukuoka, Japan from 22 to 24 November 2010. This meeting brought together again the crème de la crème of the Japanese research community investigating germline development, reprogramming and genetic networks as well as eminent international scientists. Novel trend concepts including the "reprogramming expressway", "canalization", "licensing", "epigenetic barrier", "flex points" and "hydroxymethylation" were introduced and discussed in the context of development, reprogramming and pluripotency.  相似文献   

4.
Abstract

The design of child restraints is guided in part by anthropometric data describing the distributions of body dimensions of children. However, three-dimensional body shape data have not been available for children younger than three years of age. This study presents body shape models for children weighing 9–23?kg in a seated posture relevant to child restraint design. A laboratory study collected surface geometry data of 67 children, ages 12–58 months. Novel template fitting methods were employed to obtain homologous meshes and to standardize the posture. Principal component analysis and regression were used to develop a statistical body shape model (SBSM). The SBSM was exercised to create 18 manikins representing children aged 1–3 years, with varying size and shape. These manikins will be useful for assessing child accommodation in restraints. The SBSM can also provide guidance for the development of anthropomorphic test devices and computational models of child occupants.  相似文献   

5.
Velando A 《Animal behaviour》2000,60(2):181-185
In birds, conditions and experience in the nest may influence the social rank of juveniles after they become independent. Three main factors may be involved: (1) mass at fledging, larger birds being better able to compete; (2) brood hierarchy, dominance in the brood continuing after the birds leave the nest; and (3) hatching date, birds hatching earlier having more experience and a greater ability to compete. I studied the effect of these factors on the agonistic behaviour of juvenile European shags, Phalacrocorax aristotelis, in crèches. Of all the factors, only hatching date had a significant influence on the dominance rank of juveniles. Birds that hatched earlier had a higher rank. Additionally, males were somewhat more aggressive than females. The importance of an individual's hatching date for its social rank may have consequences for its future reproductive value. Copyright 2000 The Association for the Study of Animal Behaviour.  相似文献   

6.
This study evaluated nutritional status linked to zinc levels in 239 randomly selected children at crèches in Teresina, Brazil, aged 3 to 6. Blood samples were collected after fasting of 10 h. Erythrocytary zinc levels were determined through flame atomic absorption spectrophotometry. Zinc deficiency was determined as below 40 microg Zn/g Hb. Infant linear growth was evaluated measuring weight and height, and nutritional status by height/age, weight/height, and weight/age indices, expressed as Z scores, in line with the National Center for Health Statistics. The mean zinc concentration was 35.50 +/- 10.95 microg Zn/g Hb. Zinc distribution in the 10, 50, 75, and 90 percentiles was 24.73 microg Zn/g Hb, 35.45 microg Zn/g Hb, 40.73 microg Zn/g Hb and 52.77 microg Zn/g Hb, respectively. Based on this distribution, normal values were found only from the 75th percentile and above. Since the cutoff point adopted was 40 microg Zn/g Hb, the prevalence of zinc deficiency was 74.3%. As for growth profile, 8.4% were chronically malnourished, although the statistical association between linear impairment and nutritional status regarding zinc was insignificant. The study revealed that an important segment of the infant population was mineral deficient; however, the degree of deficiency did not influence growth profiles.  相似文献   

7.
Ergonomic anthropology is a complex synthesis of studies which was formed at the borderline of anthropology, physiology and psychology. The subject of the studies is the psychosomatic status of working men interacting with techniques by means of technical tools. This status has a dual display: first, through somatometric features, known as ergonomic dimensions; second, through the subjective feelings (proprioreceptive) of a working person on the level of comfort or discomfort of the soma. The ergonomic dimensions of the body serve as a basis for calculations of the parameters of working places and reflect posture and movement activity. Three groups of methodological tasks are tested. 1. Adaptation of the anthropometric method and discovery of its specificity for ergonomics tasks. 2. Elaboration of principles and rules of applying ergonomics measurements of the body for constructing techniques. 3. The choice of objective and subjective methods of somatic comfort evaluations.  相似文献   

8.
This paper presents the results of an anthropometrical survey conducted on male and female children aged 3, 4 and 5 years in Turkey. A set of 18 body dimensions was taken from 154 males and 132 females. It is considered that the 18 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual and circulatory problems resulting from badly designed elements. This study identified significant gender differences in a set of 18 anthropometrical measures in this subject group.  相似文献   

9.
Due to the large variability in heads and faces in one population, the standard anthropometric dimensions of the head, measured from anatomical landmarks alone, may not suffice for the design of fitting headgear, e.g., helmets. To provide adequate data of the shapes and contours of the head to the designer, appropriate head models sculptured using comprehensive head dimensions, must be developed. This paper describes (a) a procedure of collecting comprehensive anthropometric data of the head using a photogrammetric method and (b) a simple sculpturing technique to reconstruct a head model of the user population.  相似文献   

10.
The purpose of this study was to establish an ergonomic basis for the integration of female personnel at military workplaces. The results of anthropometrical and physiological measurements of 1337 male and female subjects (aged 18-25 years) are presented. The empirical design included classical and functional body measures of high ergonomic relevance. Additionally, the isometric forearm-flexor and knee-extensor forces of the subjects were tested as representative variables for their physiological suitability. With regard to biometric and strength parameters, the present results clearly show only small overlaps between the sexes. Rating the 5th percentile of the male subjects as an exclusion value, the anthropometrical variables (sitting and standing body height measures, shoulder breadth, hand length and breadth etc.) show that 29% up to 72% of the women do not match this criterion. The situation becomes even worse when strength parameters are taken into consideration: Only 26% (knee extensors) respectively 3% (forearm flexors) of the females generate higher forces than the corresponding 5th percentiles of their male counterparts. The application of the database established in this survey aims at the integration of female personnel at all kinds of military workplaces; our data account for a combination of anthropometrical and physiological variables. In contrast to former systems based on isolated percentile tables, the results of our investigation make multivariate queries possible in optimization processes. This type of combined database is to be considered a useful tool for the evaluation of workplaces and personal equipment, for general ergonomic considerations and for personnel planning purposes to prevent applicants from occupational harm.  相似文献   

11.
The complexity of interactions between hereditary, environmental and cultural factors in determining human phenotypes is often underestimated in biomedical research. In this paper, we present 33 years of holistic anthropological research that was being conducted since 1971 in the island of Hvar, Croatia. During this period, detailed characterization of migrations, demography, isonymy, linguistic differences, anthropometric traits (head and body dimensions), physiological (cardio-respiratory) properties, quantitative and qualitative dermatoglyphic traits, radiogrammetric metacarpal bone dimensions and genetic traits (classical antigens, HLA diversity, DNA short tandem repeat -STR, mitochondrial DNA and Y-chromosome polymorphisms) was performed. The analysis of this large collection of data using both model-bound and model-free approaches showed that the complexity underlying human biological traits may be considerably greater than generally assumed, which has important implications for design of future studies into genetic determinants of complex traits.  相似文献   

12.
Our objective was to establish if mother's age affects the anthropometric properties their 11 and 16 years old sons, and if the boys' BMI is satisfactory. Cross-sections, questionnaires, and statistics were used for data processing BMI (kg/m2) was presented according to the scale Quetelet's index nutritional status. Twelve anthropometric properties were researched. It was established that mother's age affects anthropometric properties in adolescent boys. The younger mothers' boys come to puberty with significantly higher mean values for most anthropometric parameters. In the course of adolescent jump, older mothers' boys have significantly higher anthropometric measures in comparison to their age boys delivered by younger mothers. After the completion of their intensive growth and development anthropometric measures in both category boys are equal or insignificantly higher in younger mothers' sons. Mother's age affects their sons' anthropometric properties of growth and development, particularly in prepuberty and puberty. After puberty that effect is not significant. According to BMI, the boys coming from the researched region make the group of underfed children. That is probably the outcome of bad living conditions, irregular and insufficient diet, stress, etc. in the course of four year aggression on Bosnia and Herzegovina.  相似文献   

13.
Several examples of the need for the application of sound ergonomic principles in Singapore factories are presented. Emphasis is laid on the necessity to consider local habits and customs in the devising of ergonomic solutions to occupational health problems. Examples are given concerning vehicle cabin design, difficulties due to climate differences in applying personal protective equipment or in building design, inadequate displays warning dangers, and health consequences of technical improvements, safety measures, or measures to achieve greater efficiency. Sometimes ergonomic practices may promote productivity but be prejudicial to health. In rapidly-changing and cosmopolitan Singapore, ergonomic principles are vital to all facets of manufacturing processes and the transportation and distribution of goods, but ergonomic practice can be complicated by several factors as indicated by such examples.  相似文献   

14.
The aim of this study is to investigate whether there are differences in body dimensions between children of the same sex from endogamic and exogamic matings. The cross-sectional sample consisted of 285 children, 136 males and 149 females, 6 to 10 years old, attending elementary schools in Tortolí, a town in east-central Sardinia. The children of each sex were divided into two groups: endogamic and exogamic, the first including children from parents born in the same Sardinian village, the latter children from parents born in two different places. For each sex, ANCOVA with age as covariate revealed no significant differences between the two groups of children for the 35 anthropometric variables considered. Moreover, for each sex, there were no significant differences between the two groups of children for some anthropometric variables considered to be indicators of nutritional status: sums of skinfold thicknesses, waist/hip ratio, body mass index, total upper arm area, upper muscle arm area, upper arm fat area. We conclude that when Sardinian children of endogamous and exogamous unions are in similar nutritional conditions, they do not differ in body dimensions.  相似文献   

15.
The aim of this study was to investigate if there are differences in body dimensions among children from matings of different levels of exogamy. The cross-sectional sample consisted of 285 children, 136 males and 149 females, 6 to 10 years old, attending elementary schools in Tortoli, a town in east-central Sardinia. The children were divided into four groups according to the level of exogamy. One of them included the children of parents born in the same Sardinian village is highly endogamous. For each sex, the Kruskal-Wallis test revealed no significant differences among the four groups of children for the 35 anthropometric variables considered, with the exception of head circumference in the male sample. In particular, there were no significant differences among the four groups of children for some anthropometric variables that are considered to be indirect indicators of nutritional status: sum of skinfolds, waist/hip ratio, body mass index, total upper arm area, upper arm muscle area, upper arm fat area. We conclude that Sardinian children from marriages of different levels of exogamy do not differ in body dimensions if they have similar nutritional conditions.  相似文献   

16.

Objectives

Debate for a greater role of mid-upper arm circumference (MUAC) measures in nutritional programming continues, but a shift from therapeutic feeding programs admitting children using MUAC and/or weight-for-height Z (WHZ) to a new model admitting children using MUAC only remains complicated by limited information regarding the clinical profile and response to treatment of children selected by MUAC vs. WHZ. To broaden our understanding of how children identified for therapeutic feeding by MUAC and/or WHZ may differ, we aimed to investigate differences between children identified for therapeutic feeding by MUAC and/or WHZ in terms of demographic, anthropometric, clinical, and laboratory and treatment response characteristics.

Methods

Using secondary data from a randomized trial in rural Niger among children with uncomplicated severe acute malnutrition, we compared children that would be admitted to a therapeutic feeding program that used a single anthropometric criterion of MUAC< 115 mm vs. children that are admitted under current admission criteria (WHZ< -3 and/or MUAC< 115 mm) but would be excluded from a program that used a single MUAC< 115 mm admission criterion. We assessed differences between groups using multivariate regression, employing linear regression for continuous outcomes and log-binomial regression for dichotomous outcomes.

Results

We found no difference in terms of clinical and laboratory characteristics and discharge outcomes evaluated between children that would be included in a MUAC< 115 mm therapeutic feeding program vs. children that are currently eligible for therapeutic feeding but would be excluded from a MUAC-only program.

Conclusions

A single anthropometric admission criterion of MUAC < 115 mm did not differentiate well between children in terms of clinical or laboratory measures or program outcomes in this context. If nutritional programming is to use a single MUAC-based criterion for admission to treatment, further research and program experience can help to identify the most appropriate criterion in a broad range of contexts to target children in most urgent need of treatment.  相似文献   

17.
Wan QH  Zhang P  Ni XW  Wu HL  Chen YY  Kuang YY  Ge YF  Fang SG 《PloS one》2011,6(1):e14518
The Père David's deer is a highly inbred, but recovered, species, making it interesting to consider their adaptive molecular evolution from an immunological perspective. Prior to this study, genomic sequencing was the only method for isolating all functional MHC genes within a certain species. Here, we report a novel protocol for isolating MHC class II loci from a species, and its use to investigate the adaptive evolution of this endangered deer at the level of multi-locus haplotypes. This protocol was designated "HURRAH" based on its various steps and used to estimate the total number of MHC class II loci. We confirmed the validity of this novel protocol in the giant panda and then used it to examine the Père David's deer. Our results revealed that the Père David's deer possesses nine MHC class II loci and therefore has more functional MHC class II loci than the eight genome-sequenced mammals for which full MHC data are currently available. This could potentially account at least in part for the strong survival ability of this species in the face of severe bottlenecking. The results from the HURRAH protocol also revealed that: (1) All of the identified MHC class II loci were monomorphic at their antigen-binding regions, although DRA was dimorphic at its cytoplasmic tail; and (2) these genes constituted two asymmetric functional MHC class II multi-locus haplotypes: DRA1*01 ~ DRB1 ~ DRB3 ~ DQA1 ~ DQB2 (H1) and DRA1*02 ~ DRB2 ~ DRB4 ~ DQA2 ~ DQB1 (H2). The latter finding indicates that the current members of the deer species have lost the powerful ancestral MHC class II haplotypes of nine or more loci, and have instead fixed two relatively weak haplotypes containing five genes. As a result, the Père David's deer are currently at risk for increased susceptibility to infectious pathogens.  相似文献   

18.
Goal, Scope and Background The goal of the present paper is to demonstrate how environmental product declarations (EPDs) are developed based on a set of product category rules (PCRs) in accordance with the requirements in the ISO 14025-standard. This is demonstrated by examples from the furniture industry in Norway, where several case models are evaluated. To ease the capability of developing EPDs in this industry, a database with specific environmental data for materials in furniture is developed. The database is used to produce the LCA for selected furniture models, and further, the database is the backbone of a data-assistance tool used to create the EPDs. Methods The LCA-data are produced based on traditional LCA-methodology. The PCR is based on a stakeholder analysis and the proposed methodology in the ISO 14025-standard. The EPDs developed so far, are results of close collaboration between companies and research centres in the Nordic countries. For the verification of the EPDs, auditing methodologies are used as a part of the audit of the companies' environmental management systems (EMS). Results and Conclusion Based on a hearing of a set of suggested PCRs, a consensus document for seating accommodation is developed. This is further the model for how to develop PCR-documents for all types of furniture, for example sleeping accommodations. Likewise, the database shall contain the most important data for the parts of a furniture model. Within the goal of the project period, EPDs will be developed for 80% of Norwegian furniture. The verification of the EPDs is done as a part of the certification procedures of EMS in accordance with the ISO 14001. Recommendation and Perspective The results presented in the paper are mainly for the pilot models in the project. However, the results will be further tested and the data-tool will be developed as a part of a product design tool where environmental requirements will be combined with quality requirements. The product design tool will be implemented in the furniture industry. Information on how to use EPDs in public purchasing will also be a part of future work.  相似文献   

19.
We developed a model to predict the three-dimensional canine pelvic limb muscular geometry (i.e., all muscle moment arms during any instant in gait). Forty-one muscle origins and insertions, as well as external landmarks (to obtain anthropometric dimensions) were marked on both pelvic limbs of five dogs and digitized on biplanar radiographs. Reference frames in the pelvis, femur, and tibia established the three-dimensional coordinates of each origin, insertion, and landmark. A set of dimensionless 'scaled coordinates' was created by dividing the actual origin and insertion coordinates by selected anthropometric dimensions of each animal. Combining scaled coordinates from all ten limbs produced an averaged 'template' of scaled coordinates. To provide limited validation of the scaling procedure, we measured the anthropometric dimensions between externally palpable landmarks of two additional pelvic limbs. The anthropometric dimensions were multiplied by the averaged template coordinates to calculate two new sets of hindlimb muscle coordinates within the three bony reference frames. The two limbs then were dissected, muscle endpoints were marked, and biplanar radiographs of each of the limb segments were digitized. The actual coordinates so obtained were similar to those predicted by the template and anthropometric measures.  相似文献   

20.
In a small agropastoral Aymara community called Wariscata in the Andean Altiplano of Bolivia, anthropometric measurements were made in 1988. In comparison with those of published data for the other rural and urban Andean populations (Aymara, Quechua and Mestizo at high and low altitudes), the Aymara children of Wariscata were taller and heavier than other rural high altitude native children, but similar in height to urban high altitude children. This is possibly due to secular change of growth accompanied with nutritional improvement that has taken place in recent years. Chest width and depth had similar values to those in other Aymara children. But, Aymara children in Wariscata of both sexes had smaller chest dimensions (depth and width) than those of Quechua children. However, these ethnic differences in chest dimensions were not reflected in the adult Aymara and Quechua, suggesting different process of chest growth in Aymara and Quechua populations.  相似文献   

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