Nutritional determinants of high-altitude growth in nuñoa,Peru

Data on nutritional intake and patterns of physical growth in the rural Andean community of Nuñoa, Peru (elevation 4,000 m), are described and compared to data previously collected from this location. Food consumption data and selected anthropometric measures were obtained from a sample of 33 households. Estimates of caloric intake from this study are very similar to those obtained in Nuñoa during the mid- and late 1960s. However, within the present sample, upper income (i.e., middle class) individuals have significantly higher caloric intakes than those of the lower income group and also appear to have an improved diet relative to individuals of 20 years ago. Anthropometric data show that children of the upper socioeconomic status (SES) group are significantly taller and heavier than the lower SES group children. Moreover, the children of the wealthier families are taller and heavier than the children measured 20 years ago at the same location, whereas the poorer children are not. These results indicate that nutritional factors have significantly contributed to the extreme pattern of slow growth previously reported for children of Nuñoa and, moreover, demonstrate how social and environmental forces interact to create differential levels of stress that contribute to variation in biological well-being.     

Catching up from early nutritional deficits? Evidence from rural Ethiopia

We examine the nutritional status of a cohort of poor Ethiopian children and their patterns of catch-up growth in height-for-age between three key development stages: age one, five and eight. We use ordinary least squares (within community) and instrumental variables analysis. During the earliest period, we find that nutritional catch-up patterns vary substantially across socioeconomic groups: average catch-up growth in height-for-age is almost perfect among children in relatively better-off households, while among the poorer children, relative height is more persistent. Between five and eight years of age, however, we find near-perfect persistence and no evidence of heterogeneity in catch-up growth. Our findings suggest that household wealth, and in particular access to services, can lead to substantial catch-up growth early on in life. However, for our sample, the window of opportunity to catch up appears to close as early as the age of five.     

Child nutrition in the transition from nomadic pastoralism to settled lifestyles: individual, household, and community-level factors

The research reported here examines child nutrition in a population that is currently experiencing a transition in subsistence, shifting from nomadic pastoralism to a variety of settled lifestyles. We investigate the range of nutritional consequences of settlement both within and between communities by examining individual, household, and community-level predictors of child nutritional status. Data are drawn from the Rendille Demographic and Health Survey, which contains anthropometric data from 1,088 children ages 6 months to 10 years, as well as socioeconomic data from 640 households drawn from one nomadic and four economically and ecologically diverse settled communities. Comparisons allow us to test the widely held assumption that settlement results in nutritional improvements. The examination of individual and household-level factors highlights several important influences on child nutrition. We find a complex interaction between gender and birthorder, whereby firstborn sons have significantly higher weight-for-height scores than other children, potentially reflecting preference under a system of primogeniture. We also find a complex interaction between defacto female-headed households, where males are absent for over half of the year, and economic status. Young children from poor female-headed households have significantly lower weight-for-height than other children, possibly due to the fact that these households are amongst the poorest in the entire community. However, young children from economically sufficient female-headed households actually fare better than their counterparts in male headed households, suggesting that in households with any discretionary resources, female heads prioritize food acquisition relative to other concerns. Finally, our comparison of child nutritional status across communities, while controlling for individual and household-level variation, does not support the contention that settlement is associated with nutritional improvements. Rather, the effect of community, and its associated changes in subsistence and lifestyle, results in either no nutritional changes, or in the case of young children in the lowland desert community of Korr, diminished nutritional status. Our results underscore the importance of considering variation in sample composition and socioeconomic status when performing community comparisons, and highlight the central role of women in influencing the nutritional welfare of their families.     

Heritability of anthropometric phenotypes in caste populations of Visakhapatnam,India

In this study, we used anthropometric data from six Andhra caste populations to examine heritability patterns of 23 anthropometric phenotypes (linear, craniofacial, and soft tissue measures) with special reference to caste differences. We obtained anthropometric data from 342 nuclear families from Brahmin, Reddy, Telaga, Nagara, Ag. Kshatriya, and Mala castes of Visakhapatnam, India. These caste groups represent the existing hierarchical stratification of Indian populations. We used a variance components approach to determine the heritability (h2) of these 23 anthropometric phenotypes (height, weight, BMI, etc.). The sample consisted of 1918 individuals ranging in age from 6 to 72 years (mean = 21.5, S.D. = 13.8). The heritabilities (h2 +/- S.E.) for all anthropometric traits for the entire sample were significant (p < 0.0001) and varied from 0.25 +/- 0.05 (BMI) to 0.61 +/- 0.05 (bizygomatic breadth) after accounting for sex, age, and caste effects. Since data on socioeconomic and nutritional covariates were available for a subset of families, we repeated the genetic analyses using this subset, which has yielded higher heritabilities ranging from 0.21 +/- 0.16 (head breadth) to 0.72 +/- 0.18 (nasal breadth). In general, craniofacial measurements exhibited higher h2 compared to linear measures. Breadth measurements and circumferences yielded more or less similar heritabilities. Age and sex effects were significant (p < 0.0001 ) for most of the traits, while the effects of caste, socioeconomic status, and nutritional status were inconsistent across the traits. In conclusion, anthropometric phenotypes examined in this study are under appreciable additive genetic influences.     

Cloning and characterization of variable-sized gypsy mobile elements in Drosophila melanogaster

A cosmid genomic library from a known gypsy-induced forked mutation, f1, was screened by 32P-labeled gypsy transposable element. Of more than 250 positive clones we randomly selected 21 for in situ hybridization to wild-type polytene chromosomes. Two clones hybridized to region 15F on the X-chromosome, the cytological position of forked. A third clone hybridized to at least 17 sites on the chromosomes indicating the presence of repetitive sequences in the gypsy flanking DNA. All clones labeled the centromeric regions heavily. Ten clones, including the two hybridizing at 15F, were chosen for further analysis, and restriction mapping allowed us to place them into three groups: (1) full-length, (2) slightly diverging, and (3) highly diverging gypsy elements. Group (2) is missing the XbaI site in both their long terminal repeats (LTRs) as well as the middle HindIII site; four of these gypsy elements also have a approximately 100-bp deletion at the 5' LTR. The group (3) gypsy transposons are missing one LTR and also have highly diverging DNA sequences. The restriction analyses further imply that most of these different gypsy elements are present in more than one copy in the genome of the f1 stock used in this study. The results raise intriguing questions regarding the significance of transposable elements in evolution and biological functions.     

Sample pooling obscures diversity patterns in intertidal ciliate community composition and structure

The aim of this study was to assess the effect of sample pooling on the portrayal of ciliate community structure and composition in intertidal sediment samples. Molecular ciliate community profiles were obtained from nine biological replicates distributed in three discrete sampling plots and from samples that were pooled prior to RNA extraction using terminal restriction fragment polymorphism (T-RFLP) analyses of SSU rRNA. Comparing the individual replicates of one sampling plot with each other, we found a differential variability among the individual biological replicates. T-RFLP profiles of pooled samples displayed a significantly different community composition compared with the cumulative individual biological replicate samples. We conclude that sample pooling obscures diversity patterns in ciliate and possibly also other microbial eukaryote studies. However, differences between pooled samples and replicates were less pronounced when community structure was analyzed. We found that the most abundant T-RFLP peaks were generally shared between biological replicates and pooled samples. Assuming that the most abundant taxa in an ecosystem under study are also the ones driving ecosystem processes, sample pooling may still be effective for the analyses of ecological key players.     

Demographic behaviour of adults of mixed ethnic ancestry: Jews in Israel

We examine demographic behaviour of Jewish adults of mixed ethnic ancestry, relative to those of the two major Jewish ethnic groups in Israel. Research has shown that for measures of socioeconomic status, such as educational attainment, outcomes for multi-ethnics are in between – and very close to the middle of – those associated with the two major ethnic groups. We find that, in contrast, the marriage and fertility behaviour of multi-ethnic adults is nearly identical to that of the more socially advantaged ethnic group and quite distinct from that of the less advantaged ethnic group. Through multivariate analyses, we explore factors associated with families of origin, including socioeconomic status and cultural indicators of family norms, which are associated with these patterns. We discuss interpretations of our findings.     

Lepidoptera‐specific insecticide used to suppress gypsy moth outbreaks may benefit non‐target forest Lepidoptera

相似文献   

Structural and evolutionary analyses of the Ty3/gypsy group of LTR retrotransposons in the genome of Anopheles gambiae

The recent availability of the genome of Anopheles gambiae offers an extraordinary opportunity for comparative studies of the diversity of transposable elements (TEs) and their evolutionary dynamics between two related species, taking advantage of the existing information from Drosophila melanogaster. To this goal, we screened the genome of A. gambiae for elements belonging to the Ty3/gypsy group of long-terminal repeat (LTR) retrotransposons. The A. gambiae genome displays a rich diversity of LTR retrotransposons, clearly greater than D. melanogaster. We have characterized in detail 63 families, belonging to five of the nine main lineages of the Ty3/gypsy group. The Mag lineage is the most diverse and abundant, with more than 30 families. In sharp contrast with this finding, a single family belonging to this lineage has been found in D. melanogaster, here reported for the first time in the literature, most probably consisting of old inactive elements. The CsRn1 lineage is also abundant in A. gambiae but almost absent from D. melanogaster. Conversely, the Osvaldo lineage has been detected in Drosophila but not in Anopheles. Comparison of structural characteristics of different families led to the identification of several lineage-specific features such as the primer-binding site (PBS), the gag-pol translational recoding signal (TRS), which is extraordinarily diverse within the Ty3/gypsy retrotransposons of A. gambiae, or the presence/absence of specific amino acid motifs. Interestingly, some of these characteristics, although in general well conserved within lineages, may have evolved independently in particular branches of the phylogenetic tree. We also show evidence of recent activity for around 75% of the families. Nevertheless, almost all families contain a high proportion of degenerate members and solitary LTRs (solo LTRs), indicative of a lower turnover rate of retrotransposons belonging to the Ty3/gypsy group in A. gambiae than in D. melanogaster. Finally, we have detected significant overrepresentations of insertions on the X chromosome versus autosomes and of putatively active insertions on euchromatin versus heterochromatin.     

Complex, dynamic combination of physical, chemical and nutritional variables controls spatio-temporal variation of sandy beach community structure

Sandy beach ecological theory states that physical features of the beach control macrobenthic community structure on all but the most dissipative beaches. However, few studies have simultaneously evaluated the relative importance of physical, chemical and biological factors as potential explanatory variables for meso-scale spatio-temporal patterns of intertidal community structure in these systems. Here, we investigate macroinfaunal community structure of a micro-tidal sandy beach that is located on an oligotrophic subtropical coast and is influenced by seasonal estuarine input. We repeatedly sampled biological and environmental variables at a series of beach transects arranged at increasing distances from the estuary mouth. Sampling took place over a period of five months, corresponding with the transition between the dry and wet season. This allowed assessment of biological-physical relationships across chemical and nutritional gradients associated with a range of estuarine inputs. Physical, chemical, and biological response variables, as well as measures of community structure, showed significant spatio-temporal patterns. In general, bivariate relationships between biological and environmental variables were rare and weak. However, multivariate correlation approaches identified a variety of environmental variables (i.e., sampling session, the C∶N ratio of particulate organic matter, dissolved inorganic nutrient concentrations, various size fractions of photopigment concentrations, salinity and, to a lesser extent, beach width and sediment kurtosis) that either alone or combined provided significant explanatory power for spatio-temporal patterns of macroinfaunal community structure. Overall, these results showed that the macrobenthic community on Mtunzini Beach was not structured primarily by physical factors, but instead by a complex and dynamic blend of nutritional, chemical and physical drivers. This emphasises the need to recognise ocean-exposed sandy beaches as functional ecosystems in their own right.     

Evolution of gypsy endogenous retrovirus in the Drosophila obscura species group

The Ty3/gypsy family of retroelements is closely related to retroviruses, and some of their members have an open reading frame resembling the retroviral gene env. Sequences homologous to the gypsy element from Drosophila melanogaster are widely distributed among Drosophila species. In this work, we report a phylogenetic study based mainly on the analysis of the 5' region of the env gene from several species of the obscura group, and also from sequences already reported of D. melanogaster, Drosophila virilis, and Drosophila hydei. Our results indicate that the gypsy elements from species of the obscura group constitute a monophyletic group which has strongly diverged from the prototypic D. melanogaster gypsy element. Phylogenetic relationships between gypsy sequences from the obscura group are consistent with those of their hosts, indicating vertical transmission. However, D. hydei and D. virilis gypsy sequences are closely related to those of the affinis subgroup, which could be indicative of horizontal transmission.     

Reproductive pattern of three amerindian communities from Costa Rica

The bases of the reproductory models of three indigenous communities from Costa Rica belonging to the same cultural area (Chibcha) but with different social, economical and environmental conditions were studied. In this situation it was observed how the study of the data on fertility and fecundity, analyzed together with other reproductory and social characteristics of women, can precisely determine the reproductory model of the communities to which they belong. A homogeneous fecundity was presented in the studied communities, but one which responded to different reproductory patterns. Starting from the multivariate analysis of the fertility variables, the studied women were divided into two groups. One of the groups presents the highest levels of length of breast feeding period and amenorrhea, together with the near total lack of artificial breast feeding and the early introduction of normal feeding. This model is predominant among the Guaymies. The other one, together with the short period of breast feeding and amenorrhea, shows an early introduction of the bottle and a late one of solid food in the feeding process. It is characteristic of the Huetars. This links a certain reproductory model to an indigenous community and a way of life. The reproductory pattern, a clearly biological model, to an ecological and cultural environment.     

Trait and phylogenetic diversity provide insights into community assembly of reef‐associated shrimps (Palaemonidae) at different spatial scales across the Chagos Archipelago

Coral reefs are the most biodiverse marine ecosystem and one of the most threatened by global climate change impacts. The vast majority of diversity on reefs is comprised of small invertebrates that live within the reef structure, termed the cryptofauna. This component of biodiversity is hugely understudied, and many species remain undescribed. This study represents a rare analysis of assembly processes structuring a distinct group of cryptofauna, the Palaemonidae, in the Chagos Archipelago, a reef ecosystem under minimal direct human impacts in the central Indian Ocean. The Palaemonidae are a diverse group of Caridae (infraorder of shrimps) that inhabit many different niches on coral reefs and are of particular interest because of their varied habitat associations. Phylogenetic and trait diversity and phylogenetic signal were used to infer likely drivers of community structure. The mechanisms driving palaemonid community assembly and maintenance in the Chagos Archipelago showed distinct spatial patterns. At local scales, among coral colonies and among reefs fringing individual atolls, significant trait, and phylogenetic clustering patterns suggest environmental filtering may be a dominant ecological process driving Palaemonidae community structure, although local competition through equalizing mechanisms may also play a role in shaping the local community structure. Importantly, we also tested the robustness of phylogenetic diversity to changes in evolutionary information as multi‐gene phylogenies are resource intensive and for large families, such as the Palaemonidae, are often incomplete. These tests demonstrated a very modest impact on phylogenetic community structure, with only one of the four genes (PEPCK gene) in the phylogeny affecting phylogenetic diversity patterns, which provides useful information for future studies on large families with incomplete phylogenies. These findings contribute to our limited knowledge of this component of biodiversity in a marine locality as close to undisturbed by humans as can be found. It also provides a rare evaluation of phylogenetic diversity methods.     

Significant effects of birth-related biological factors on pre-adolescent nutritional status among rural Sundanese in West Java, Indonesia

The Sundanese inhabiting West Java, the second largest ethnic group in Indonesia, are characterized by a high prevalence of child malnutrition, together with high fertility. Based on an anthropometric measurement and interview survey of 310 children aged 5-12 years in a rural Sundanese village, this study examined the relative significance of the effects of eight biological, eight socioeconomic status (SES) and four health behavioural factors on their Z scores for height-for-age (HAZ) and weight-for-age (WAZ) in particular. Three biological factors, i.e. birth interval, birth weight and mother's body weight, and one SES factor, i.e. mother's occupation, were selected as the predictors of the two Z scores by regression analysis, indicating more significant effects of the biological factors than the other factors. This pattern is judged to occur in less-developed and high-fertility populations. Since these two Z scores were worse in the subject children than in the under-5-year-old children from the same village, more attention should be paid to the long-lasting effects of birth-related biological factors up to pre-adolescent ages, as an insufficient nutritional status tends to damage growth and health in adolescence and adulthood.     

紫花苜蓿草地节肢动物群落功能团和营养层的多样性

用网捕、手捕和巴氏诱罐法对紫花苜蓿草地的节肢动物进行了系统调查,采集到标本9225头,隶属15目38科81种;根据营养水平和取食关系归为3个营养层(基位物种、中位物种和顶位物种)和14个功能团,分析了苜蓿地节肢动物群落的物种、优势功能团和营养层多样性的时序动态。结果表明,在苜蓿的整个生长季节,物种多样性>功能团多样性>营养层多样性,物种多样性和营养层多样性分别与功能团多样性之间的相关性均达到极显著水平(P<0.01)。功能团多样性与物种多样性的变化趋势较一致,营养层多样性在时间序列过程中波动性较小。在群落研究中,可以用对功能团的研究代替对物种的研究,从而简化物种间复杂的网络关系。功能团多样性可用于群落相似性和稳定性分析。     

A biocultural approach to breastfeeding interactions in Central Africa

Anthropologists have long recognized that breastfeeding involves much more than feeding; it entails intimate social interactions between infants or children and their mothers. However, breastfeeding has predominantly been studied with respect to structural features (frequency, timing) as well as nutritional and health aspects of infant feeding. Thus, in this study we complement previous anthropological studies by examining social interactions that occur during breastfeeding among the Aka and Bofi foragers and Ngandu and Bofi farmers at various ages (three to four months, nine to ten months, toddlers). Further, we use an integrated biocultural perspective to explore how patterns of breastfeeding and social interactions can be shaped by economic constraints, cultural values, and children's development. Overall, our findings illustrate how biological and cultural factors interact and provide useful explanations of variations in breastfeeding structure and social interactions more so than either perspective alone.     

Morphological evolution of the lizard skull: a geometric morphometrics survey

Patterns of diversity among lizard skulls were studied from a morphological, phylogenetic, and functional perspective. A sample of 1,030 lizard skulls from 441 species in 17 families was used to create a lizard skull morphospace. This morphospace was combined with a phylogeny of lizard families to summarize general trends in the evolution of the lizard skull. A basal morphological split between the Iguania and Scleroglossa was observed. Iguanians are characterized by a short, high skull, with large areas of attachment for the external adductor musculature, relative to their sister group. The families of the Iguania appear to possess more intrafamilial morphological diversity than families of the Scleroglossa, but rarefaction of the data reveals this to be an artifact caused by the greater number of species represented in Iguanian families. Iguanian families also appear more dissimilar to one another than families of the Scleroglossa. Permutation tests indicate that this pattern is real and not due to the smaller number of families in the Iguanidae. Parallel and convergent evolution is observed among lizards with similar diets: ant and termite specialists, carnivores, and herbivores. However, these patterns are superimposed over the more general phylogenetic pattern of lizard skull diversity. This study has three central conclusions. Different clades of lizards show different patterns of disparity and divergence in patterns of morphospace occupation. Phylogeny imposes a primary signal upon which a secondary ecological signal is imprinted. Evolutionary patterns in skull metrics, taken with functional landmarks, allow testing of trends and the development of new hypotheses concerning both shape and biomechanics.     

Brazilian mothers' beliefs, attitudes and practices related to child weight status and early feeding within the context of nutrition transition

With the rapid pace of the nutrition transition worldwide, understanding influences of child feeding practices within a context characterized by the co-existence of overweight and undernutrition in the same population has increasing importance. This qualitative study describes Brazilian mothers' child feeding practices and their perceptions of their association with child weight status and explores the role of socioeconomic, cultural and organizational factors on these relationships. Forty-one women enrolled in the Family Health/Community Health Workers Programme were selected from rural, urban, coastal and indigenous areas in Ceara State, north-east Brazil, to participate in four focus group discussions. Content analysis identified fourteen emergent themes showing mothers' child feeding practices in this setting were influenced by economic resources, mothers' immediate social support networks (e.g. neighbours and family members) and participation in nutrition assistance programmes. Child malnutrition was the most common nutritional concern; nevertheless, mothers were aware of the negative health consequences of obesity but misunderstood its causes (e.g. foods filled with fat would make a person fat; others thought that birth control pills and stimulants given to children were causes of obesity); several reported their own struggles with overweight. Food assistance programmes emerged as an important influence on children's dietary adequacy, especially among mothers describing dire economic situations. The findings have implications for targeting food assistance as well as health and nutrition education strategies in low-income families undergoing the nutrition transition in north-east Brazil.     

Evolutionary patterns of the gypsy and bilbo retrotransposon families in the Drosophila species of the obscura group

We analyse in this paper the evolutionary patterns of two types of Drosophila retrotransposons, gypsy (a virus-like element), and bilbo (a LINE-like element), in host species from the Drosophila and Scaptomyza genus. Phylogenetic analysis of the retrotransposon sequences amplified by PCR, revealed concordance with the phylogeny of the Drosophila host species from the obscura group, which is consistent with vertical transmission during differentiation of the species. However, in the species outside of the obscura group, horizontal transmission can be considered. The amplified sequences that presented intact open reading frames were used in an analysis of the evolutionary constraints on the amino acid sequences. The analysed sequences seem to be functional, and the selective constraints are evidenced, especially when sequences from distant species are compared. Comparison of the evolutionary rates of both retrotransposons in the same species, suggests that bilbo seems to evolve more rapidly than gypsy.     

C-value estimates for 31 species of ladybird beetles (Coleoptera: Coccinellidae)

This study provides C-value (haploid nuclear DNA content) estimates for 31 species of ladybird beetles (representing 6 subfamilies and 8 tribes), the first such data for the family Coccinellidae. Despite their unparalleled diversity, the Coleoptera have been very poorly studied in terms of genome size variation, such that even this relatively modest sample of species makes the Coccinellidae the third best studied family of beetles, behind the Tenebrionidae and Chrysomelidae. The present study provides a comparison of patterns of genome size variation with these two relatively well-studied families. No correlation was found between genome size and body size in the ladybirds, in contrast to some other invertebrate groups but in keeping with findings for other beetle families. However, there is some indication that developmental time and/or feeding ecology is related to genome size in this group. Some phylogenetic patterns and possible associations with subgenomic features are also discussed.