Exploring the factors contributing to sibling correlations in BMI: a study using the Panel Study of Income Dynamics

Understanding the mechanisms contributing to correlated BMI outcomes in a social network such as siblings will help policy makers reduce the burden of disease associated with obesity. There are two potential mechanisms explaining correlated BMI outcomes in a biologically related social network: (i) time constant factors such as genetic heritability and habits formed during childhood and (ii) factors that change over time some of which are dependent on the frequency of interactions between the social network, for example, social norms shaped by the social network's shifting attitudes towards weight and behaviors related to weight, or environmental factors like opportunities for exercise. This study aims to distinguish between time constant factors from factors that are likely to change over time to gain a better understanding of the mechanisms explaining the correlation in sibling BMI. We exploit data from the Panel Study of Income Dynamics (PSID) over 1999-2007 estimating the correlation in BMI for adult siblings who currently live in separate households but grew-up in the same household and adolescent siblings currently living in the same household to isolate the influence of factors that change over time. The findings indicate that time constant factors explain some of the overall correlation in sibling BMI for both cohorts of siblings. Factors that change over time only significantly impact on the overall correlation in BMI for adolescent siblings suggesting if there is a social network influence on correlations in BMI this is facilitated by sharing the same household.     

The circulatory system: blood procurement, AIDS, and the social body in China

The market for blood thrived in China for more than a decade, preying on rural villagers desperate for cash. Profit motives and unhygienic collection created an AIDS epidemic, where now up to 80 percent of adults in some villages are HIV infected. Today, illegal blood banks continue to operate in some areas. Moreover, better screening and blood testing do little to address the underlying cultural reluctance to give blood. This article examines what is at stake for blood donors in the circulation of blood through both the physical and the social bodies in China today. I argue that public health and social policy solutions require consideration of the symbolic meanings of blood and the body, kin relations, and gift exchange. China's HIV-contaminated blood procurement crisis demands a critical reexamination of the hidden processes embedded in a "circulatory system" that has inseparably bound the "gift of life" and a "commodity of death".     

Quantification of Goods Purchases and Waste Generation at the Level of Individual Households

Quantifying differences in resource use and waste generation between individual households and exploring the reasons for the variations observed implies the need for disaggregated data on household activities and related physical flows. The collection of disaggregated data for water use, gas use, electricity use, and mobility has been reported in the literature and is normally achieved through sensors and computational algorithms. This study focuses on collecting disaggregated data for goods consumption and related waste generation at the level of individual households. To this end, two data collection approaches were devised and evaluated: (1) triangulating shopping receipt analysis and waste component analysis and (2) tracking goods consumption and waste generation using a smartphone. A case study on two households demonstrated that it is possible to collect quantitative data on goods consumption and related waste generation on a per unit basis for individual households. The study suggested that the type of data collected can be relevant in a number of different research contexts: eco‐feedback; user‐centered research; living‐lab research; and life cycle impacts of household consumption. The approaches presented in this study are most applicable in the context of user‐centered or living‐lab research. For the other contexts, alternative data sources (e.g., retailers and producers) may be better suited to data collection on larger samples, though at a lesser level of detail, compared with the two data collection approaches devised and evaluated in this study.     

The effects of data collection and observation methods on uncertainty of social networks in wild primates

In social species, network centralities of group members shape social transmission and other social phenomena. Different factors have been found to influence the measurement of social networks, such as data collection and observation methods. In this study, we collected data on adults and juveniles and examined the effect of data collection method (ad libitum sampling vs. focal animal sampling) and observation method (interaction—grooming; play—vs. association—arm-length; 2 m; 5 m proximities—) on social networks in wild vervet monkeys. First, we showed using a bootstrapping method, that uncertainty of ad libitum grooming and play matrices were lesser than uncertainty of focal matrices. Nevertheless, grooming and play networks constructed from ad libitum and focal animal sampling were very similar and highly correlated. We improved the certainty of both grooming and play networks by pooling focal and ad libitum matrices. Second, we reported a high correlation between the proximity arm-length network and the focal grooming one making an arm-length proximity network a reasonable proxy for a grooming one in vervet monkeys. However, we did not find such a correlation between proximity networks and the play one. Studying the effects of methodological issues as data collection and observation methods can help improve understanding of what shapes social networks and which data collection method to choose to study sociality.     

Individual and Collective Rationality in Pastoral Production: Evidence From Northern Kenya

This study explores the individual and collective rationality of livestock accumulation in pastoral production using data gathered in northern Kenya. Results suggest accumulating wealth in livestock even when facing the prospect of sudden dramatic loss makes sense at the household level, and that there is limited empirical support to the contention that herd accumulation at the household level imposes a cost on other households. I conclude by arguing the record of failure in pastoral development may be at least partially due to a faulty conceptual foundation, and suggest facilitating herd accumulation may offer more promise than discouraging it.     

Social Network Analysis Predicts Health Behaviours and Self-Reported Health in African Villages

The provision of healthcare in rural African communities is a highly complex and largely unsolved problem. Two main difficulties are the identification of individuals that are most likely affected by disease and the prediction of responses to health interventions. Social networks have been shown to capture health outcomes in a variety of contexts. Yet, it is an open question as to what extent social network analysis can identify and distinguish among households that are most likely to report poor health and those most likely to respond to positive behavioural influences. We use data from seven highly remote, post-conflict villages in Liberia and compare two prominent network measures: in-degree and betweenness. We define in-degree as the frequency in which members from one household are named by another household as a friends. Betweenness is defined as the proportion of shortest friendship paths between any two households in a network that traverses a particular household. We find that in-degree explains the number of ill family members, whereas betweenness explains engagement in preventative health. In-degree and betweenness independently explained self-reported health and behaviour, respectively. Further, we find that betweenness predicts susceptibility to, instead of influence over, good health behaviours. The results suggest that targeting households based on network measures rather than health status may be effective for promoting the uptake of health interventions in rural poor villages.     

A social network analysis of primate groups

Primate social systems are difficult to characterize, and existing classification schemes have been criticized for being overly simplifying, formulated only on a verbal level or partly inconsistent. Social network analysis comprises a collection of analytical tools rooted in the framework of graph theory that were developed to study human social interaction patterns. More recently these techniques have been successfully applied to examine animal societies. Primate social systems differ from those of humans in both size and density, requiring an approach that puts more emphasis on the quality of relationships. Here, we discuss a set of network measures that are useful to describe primate social organization and we present the results of a network analysis of 70 groups from 30 different species. For this purpose we concentrated on structural measures on the group level, describing the distribution of interaction patterns, centrality, and group structuring. We found considerable variability in those measures, reflecting the high degree of diversity of primate social organizations. By characterizing primate groups in terms of their network metrics we can draw a much finer picture of their internal structure that might be useful for species comparisons as well as the interpretation of social behavior.     

How to make methodological decisions when inferring social networks

Social network analyses allow studying the processes underlying the associations between individuals and the consequences of those associations. Constructing and analyzing social networks can be challenging, especially when designing new studies as researchers are confronted with decisions about how to collect data and construct networks, and the answers are not always straightforward. The current lack of guidance on building a social network for a new study system might lead researchers to try several different methods and risk generating false results arising from multiple hypotheses testing. Here, we suggest an approach for making decisions when starting social network research in a new study system that avoids the pitfall of multiple hypotheses testing. We argue that best edge definition for a network is a decision that can be made using a priori knowledge about the species and that is independent from the hypotheses that the network will ultimately be used to evaluate. We illustrate this approach with a study conducted on a colonial cooperatively breeding bird, the sociable weaver. We first identified two ways of collecting data using different numbers of feeders and three ways to define associations among birds. We then evaluated which combination of data collection and association definition maximized (a) the assortment of individuals into previously known “breeding groups” (birds that contribute toward the same nest and maintain cohesion when foraging) and (b) socially differentiated relationships (more strong and weak relationships than expected by chance). This evaluation of different methods based on a priori knowledge of the study species can be implemented in a diverse array of study systems and makes the case for using existing, biologically meaningful knowledge about a system to help navigate the myriad of methodological decisions about data collection and network inference.     

Bride‐service and the absent gift

Building on a previous experiment to apply Strathern's discussions of Melanesian gift exchange to ethnography relating to Tukanoan societies in Northwest Amazonia, this essay asks why other authors should repeatedly affirm that the gift has no relevance in the Amazonian context. Two answers are proposed. Firstly, the authors concerned tend to assume that a particular type of social formation is characteristic of Amazonia as a whole. The Tukanoans, who engage in ceremonial exchange of food and goods, do not fit this rubric. Secondly, despite their differences, these authors assume that Amazonian societies are bride‐service societies where, axiomatically, there can be no gift. The Tukanoans are not bride‐service societies and, if anything, tend towards the bride‐wealth alternative. This Tukanoan exception serves to re‐emphasize the diversity of Amazonian social formations, one that would have been even greater in the archaeological past. It also warns against the dangers of over‐hasty theoretical closure.     

A multilevel analytical framework for studying cultural evolution in prehistoric hunter–gatherer societies

Over the past decade, a major debate has taken place on the underpinnings of cultural changes in human societies. A growing array of evidence in behavioural and evolutionary biology has revealed that social connectivity among populations and within them affects, and is affected by, culture. Yet the interplay between prehistoric hunter–gatherer social structure and cultural transmission has typically been overlooked. Interestingly, the archaeological record contains large data sets, allowing us to track cultural changes over thousands of years: they thus offer a unique opportunity to shed light on long‐term cultural transmission processes. In this review, we demonstrate how well‐developed methods for social structure analysis can increase our understanding of the selective pressures underlying cumulative culture. We propose a multilevel analytical framework that considers finer aspects of the complex social structure in which regional groups of prehistoric hunter–gatherers were embedded. We put forward predictions of cultural transmission based on local‐ and global‐level network metrics of small‐scale societies and their potential effects on cumulative culture. By bridging the gaps between network science, palaeodemography and cultural evolution, we draw attention to the use of the archaeological record to depict patterns of social interactions and transmission variability. We argue that this new framework will contribute to improving our understanding of social interaction patterns, as well as the contexts in which cultural changes occur. Ultimately, this may provide insights into the evolution of human behaviour.     

Social,Economic, and Resource Predictors of Variability in Household Air Pollution from Cookstove Emissions

We examine if social and economic factors, fuelwood availability, market and media access are associated with owning a modified stove and variation in household emissions from biomass combustion, a significant environmental and health concern in rural India. We analyze cross-sectional household socio-economic data, and PM_2.5 and particulate surface area concentration in household emissions from cookstoves (n = 100). This data set combines household social and economic variables with particle emissions indexes associated with the household stove. The data are from the Foundation for Ecological Society, India, from a field study of household emissions. In our analysis, we find that less access to ready and free fuelwood and higher wealth are associated with owning a replacement/modified stove. We also find that additional kitchen ventilation is associated with a 12% reduction in particulate emissions concentration (p<0.05), after we account for the type of stove used. We did not find a significant association between replacement/modified stove on household emissions when controlling for additional ventilation. Higher wealth and education are associated with having additional ventilation. Social caste, market and media access did not have any effect on the presence of replacement or modified stoves or additional ventilation. While the data available to us does not allow an examination of direct health outcomes from emissions variations, adverse environmental and health impacts of toxic household emissions are well established elsewhere in the literature. The value of this study is in its further examination of the role of social and economic factors and available fuelwood from commons in type of stove use, and additional ventilation, and their effect on household emissions. These associations are important since the two direct routes to improving household air quality among the poor are stove type and better ventilation.     

Composition and structure of a large online social network in The Netherlands

Limitations in data collection have long been an obstacle in research on friendship networks. Most earlier studies use either a sample of ego-networks, or complete network data on a relatively small group (e.g., a single organization). The rise of online social networking services such as Friendster and Facebook, however, provides researchers with opportunities to study friendship networks on a much larger scale. This study uses complete network data from Hyves, a popular online social networking service in The Netherlands, comprising over eight million members and over 400 million online friendship relations. In the first study of its kind for The Netherlands, I examine the structure of this network in terms of the degree distribution, characteristic path length, clustering, and degree assortativity. Results indicate that this network shares features of other large complex networks, but also deviates in other respects. In addition, a comparison with other online social networks shows that these networks show remarkable similarities.     

青藏高原牧区家庭能源消费对生态环境和人体健康的影响研究现状与展望

探究家庭能源消费对生态环境和人体健康的研究是系统推进家庭能源绿色低碳转型和实现联合国2030可持续发展目标的关键。重点综述了目前家庭能源消费、影响因素及其对生态环境和居民健康影响的国际研究现状。目前研究不足主要聚焦在以下两个方面：一方面,影响家庭能源消费因素的贡献率和影响消费行为的驱动机制尚不清晰;另一方面,目前主要针对家庭能源消费或者生态系统或者环境或者居民健康其中的某一方面或者某两个方面开展研究,鲜有研究系统的考虑家庭能源消费对生态环境和人体健康影响的综合研究。基于上述研究现状,结合青藏高原的实际情况,提出未来需要在宏观层面和微观层面加强研究。宏观层面：(1)亟需厘清青藏高原家庭能源与生态环境和人体健康之间的内在联系与驱动机制,形成青藏高原牧区“家庭能源-生态效应-环境效应-健康效应”的理论分析框架;(2)构建模块化的牧区“能源-生态-环境-健康-经济”等多学科交叉的综合评估模型,形成完整的、系统的评估方法。微观层面：(1)迫切开展青藏高原家庭能源消费特征与变化规律的研究;(2)深入开展家庭能源消费特征和变化规律与生态系统的反馈机制与量化研究;(3)加强牧区室内空气污染物浓度测定,...     

The Biological Records Centre–a data centre

The Biological Records Centre collects data on the occurrence of species at a particular time in a particular place. These data are used for the preparation of distribution maps, for lists of species from localities, and lists of localities for species.
The unit of recording at the national level is the 10 km square: from each square a list as complete as possible is collected. For common species presence alone is sufficient, but for rare or critical species more detailed data on locality and source are required.
Mapping data are stored on magnetic tape from which 80-column cards are generated by computer. These cards prepare distribution maps on an electric typewriter through a card reader. Details of locality, habitat, etc. are stored on two sets of 80-column individual record cards, one stored by species and the other by localities.
The Centre is encouraging the collection of data in counties, where the 2times2 km square is used, and for Europe where the 50 times 50 km square is proposed. It is important to establish not only biological records centres but a complete biological recording network.     

Social status,social context,and arterial blood pressure

As social change and economic development have proceeded, the prevalence of chronic diseases, especially cardiovascular diseases, has increased in the developing world. In part this is due to the adoption of diets and other health behaviors characteristic of industrialized nations; in part it is a function of changing social and economic circumstances. In this paper, we describe the development and testing of a model designed to account for social and economic effects on cardiovascular disease risk. The model incorporates the fact that global economic processes have made a lifestyle characterized by the consumption of Euroamerican material goods and information a basis for the assignment of social status in local communities. But economic change at the local level is rarely sufficient to provide a foundation for individuals' status aspirations. Hence, many individuals attempt to maintain a lifestyle inconsistent with their economic standing, a variable we term lifestyle incongruity. Here we describe how this factor is associated with higher blood pressure in a variety of settings and also how the effects of lifestyle incongruity can be modified in local contexts by social class and social role processes. This latter process, contextual modification, is illustrated by data from American Samoa. In this example, the association of lifestyle incongruity with blood pressure is examined in 30 male household heads and 26 spouses. After an examination of Samoan ethnography focused attention on the importance of age and gender differences as defining social contexts of intracultural variation, the model was modified to assess interactions between age and gender as they affect the association of lifestyle incongruity and blood pressure. Lifestyle incongruity is strongly associated with higher systolic and diastolic blood pressure for the younger household heads, minimally associated with blood pressure for older household heads, and only slightly associated with the blood pressure of their spouses. The regression coefficients for the lifestyle incongruity by age by sex interaction term was significant at P ≤ 0.01 for both systolic and diastolic blood pressure. The consistency of these results with expectations based on the ethnographic record is emphasized in the interpretation. We feel that the lifestyle incongruity model represents an empirically successful attempt to link global political-economic processes, local social structure, and biological outcomes. Am J Phys Anthropol 102:55–66, 1997. © 1997 Wiley-Liss, Inc.     

Proximity data-loggers increase the quantity and quality of social network data

Social network analysis is an ideal quantitative tool for advancing our understanding of complex social behaviour. However, this approach is often limited by the challenges of accurately characterizing social structure and measuring network heterogeneity. Technological advances have facilitated the study of social networks, but to date, all such work has focused on large vertebrates. Here, we provide proof of concept for using proximity data-logging to quantify the frequency of social interactions, construct weighted networks and characterize variation in the social behaviour of a lek-breeding bird, the wire-tailed manakin, Pipra filicauda. Our results highlight how this approach can ameliorate the challenges of social network data collection and analysis by concurrently improving data quality and quantity.     

A new digital field data collection system for dendrochronology

A wide variety of information or ‘metadata’ is required when undertaking dendrochronological sampling. Traditionally, researchers record observations and measurements on field notebooks and/or paper recording forms, and use digital cameras and hand-held GPS devices to capture images and record locations. In the lab, field notes are often manually entered into spreadsheets or personal databases, which are then sometimes linked to images and GPS waypoints. This process is both time consuming and prone to human and instrument error. Specialised hardware technology exists to marry these data sources, but costs can be prohibitive for small scale operations (>$2000 USD). Such systems often include proprietary software that is tailored to very specific needs and might require a high level of expertise to use. We report on the successful testing and deployment of a dendrochronological field data collection system utilising affordable off-the-shelf devices ($100–300 USD). The method builds upon established open source software that has been widely used in developing countries for public health projects as well as to assist in disaster recovery operations. It includes customisable forms for digital data entry in the field, and a marrying of accurate GPS location with geotagged photographs (with possible extensions to other measuring devices via Bluetooth) into structured data fields that are easy to learn and operate. Digital data collection is less prone to human error and efficiently captures a range of important metadata. In our experience, the hardware proved field worthy in terms of size, ruggedness, and dependability (e.g., battery life). The system integrates directly with the Tellervo software to both create forms and populate the database, providing end users with the ability to tailor the solution to their particular field data collection needs.     

Women’s Preference for a Male Acquaintance Enhances Social Reward Processing of Material Goods in the Anterior Cingulate Cortex

Men, like the male of many animal species, use gifts to build satisfactory relationships with a desired woman. From the woman’s perspective, all gifts are not always equally rewarding; the reward value of a gift depends on two factors: (1) the giver and (2) the type of the gift (the gift’s social meaning). In this study, we investigated how these two factors interactively determine the reward value of a gift. Specifically, we examined how the neural processing for understanding a gift’s social meaning is modulated by preferences for the giver. We performed a functional magnetic resonance imaging (fMRI) study in which a female participant was asked to judge a gift from a male she was acquainted with in real life. We examined the interactive effects between (1) the female participant’s attitude toward the male acquaintance (liked vs. uninteresting) and (2) the type of the gift (romantic [e.g., bouquet, earrings, and perfumes] vs. non-romantic [e.g., pencils, memo pad, and moneybox]). We found that preference for an acquaintance selectively modulated activity in the anterior cingulate cortex (ACC) in response to romantic gifts, compared to non-romantic gifts. In contrast, if the woman was indifferent toward an acquaintance, no activity modulation was observed in this area for the same gifts. In addition, the ACC showed functional connectivity with the supplementary motor area/dorsal ACC (SMA/dACC), an area within the dorsal mediofrontal cortex, suggesting that it integrates action monitoring and emotional and cognitive processing in decision-making. These results suggest that attitude toward an opposite sex member has a modulatory role in recognizing the social meaning of material goods—preference for the member is a powerful modulator of social reward processing.     

Leadership and Path Characteristics during Walks Are Linked to Dominance Order and Individual Traits in Dogs

Movement interactions and the underlying social structure in groups have relevance across many social-living species. Collective motion of groups could be based on an “egalitarian” decision system, but in practice it is often influenced by underlying social network structures and by individual characteristics. We investigated whether dominance rank and personality traits are linked to leader and follower roles during joint motion of family dogs. We obtained high-resolution spatio-temporal GPS trajectory data (823,148 data points) from six dogs belonging to the same household and their owner during 14 30–40 min unleashed walks. We identified several features of the dogs'' paths (e.g., running speed or distance from the owner) which are characteristic of a given dog. A directional correlation analysis quantifies interactions between pairs of dogs that run loops jointly. We found that dogs play the role of the leader about 50–85% of the time, i.e. the leader and follower roles in a given pair are dynamically interchangable. However, on a longer timescale tendencies to lead differ consistently. The network constructed from these loose leader–follower relations is hierarchical, and the dogs'' positions in the network correlates with the age, dominance rank, trainability, controllability, and aggression measures derived from personality questionnaires. We demonstrated the possibility of determining dominance rank and personality traits of an individual based only on its logged movement data. The collective motion of dogs is influenced by underlying social network structures and by characteristics such as personality differences. Our findings could pave the way for automated animal personality and human social interaction measurements.     

中国城市家庭代谢及其影响因素分析

家庭是可持续消费研究的主要对象,为了分析家庭消费的环境影响,荷兰的HOMES项目将代谢的概念引入家庭,提出了家庭代谢的概念。目前家庭代谢分析是评价家庭消费活动环境影响的主要方法,它通过对家庭系统中物质和能量流动过程的描述,来识别家庭消费的环境结果。本文首先介绍了家庭代谢的概念模型,该模型中包含着代谢流的方向、流量和速度3个要素,水资源、能源和物质代谢是家庭代谢的主要内容。应用这一模型,对中国城市家庭近20a的水资源和能源代谢进行描述,对家庭代谢的经济及人口社会因素进行了分析。结果表明,中国城市家庭的代谢量在可预见的短-中期时间内,将继续保持增加的趋势。