Optimising between and within family selection for harvest weight in prawns with restricted harvest size.

Manual grading of prawns restricts the number that can be harvested. A restricted harvest size places a limit on the opposing within family and between family sources of selection pressure. A simulation study with inbreeding constrained at 0.5% per generation, a harvest size of 2000, heritability of 0.3, common family environmental effect of 0.1, indicates that maximum response to selection could be achieved with as few as 40 families. Increasing the number of families above 80 may reduce total selection response. It is important to be aware that increasing the number of families may not always yield a greater genetic response.

Within-family outliers: Segregating alleles or environmental effects? A linkage analysis of height from 5815 sibling pairs

Most information in linkage analysis for quantitative traits comes from pairs of relatives that are phenotypically most discordant or concordant. Confounding this, within-family outliers from non-genetic causes may create false positives and negatives. We investigated the influence of within-family outliers empirically, using one of the largest genome-wide linkage scans for height. The subjects were drawn from Australian twin cohorts consisting of 8447 individuals in 2861 families, providing a total of 5815 possible pairs of siblings in sibships. A variance component linkage analysis was performed, either including or excluding the within-family outliers. Using the entire dataset, the largest LOD scores were on chromosome 15q (LOD 2.3) and 11q (1.5). Excluding within-family outliers increased the LOD score for most regions, but the LOD score on chromosome 15 decreased from 2.3 to 1.2, suggesting that the outliers may create false negatives and false positives, although rare alleles of large effect may also be an explanation. Several regions suggestive of linkage to height were found after removing the outliers, including 1q23.1 (2.0), 3q22.1 (1.9) and 5q32 (2.3). We conclude that the investigation of the effect of within-family outliers, which is usually neglected, should be a standard quality control measure in linkage analysis for complex traits and may reduce the noise for the search of common variants of modest effect size as well as help identify rare variants of large effect and clinical significance. We suggest that the effect of within-family outliers deserves further investigation via theoretical and simulation studies.

Genetic heterogeneity of within-family variance of body weight in Atlantic salmon (Salmo salar)

BACKGROUND: Canalization is defined as the stability of a genotype against minor variations in both environment and genetics. Genetic variation in degree of canalization causes heterogeneity of within-family variance. The aims of this study are twofold: (1) quantify genetic heterogeneity of (within-family) residual variance in Atlantic salmon and (2) test whether the observed heterogeneity of (within-family) residual variance can be explained by simple scaling effects. RESULTS: Analysis of body weight in Atlantic salmon using a double hierarchical generalized linear model (DHGLM) revealed substantial heterogeneity of within-family variance. The 95% prediction interval for within-family variance ranged from ~0.4 to 1.2 kg2, implying that the within-family variance of the most extreme high families is expected to be approximately three times larger than the extreme low families. For cross-sectional data, DHGLM with an animal mean sub-model resulted in severe bias, while a corresponding sire-dam model was appropriate. Heterogeneity of variance was not sensitive to Box-Cox transformations of phenotypes, which implies that heterogeneity of variance exists beyond what would be expected from simple scaling effects. CONCLUSIONS: Substantial heterogeneity of within-family variance was found for body weight in Atlantic salmon. A tendency towards higher variance with higher means (scaling effects) was observed, but heterogeneity of within-family variance existed beyond what could be explained by simple scaling effects. For cross-sectional data, using the animal mean sub-model in the DHGLM resulted in biased estimates of variance components, which differed substantially both from a standard linear mean animal model and a sire-dam DHGLM model. Although genetic differences in canalization were observed, selection for increased canalization is difficult, because there is limited individual information for the variance sub-model, especially when based on cross-sectional data. Furthermore, potential macro-environmental changes (diet, climatic region, etc.) may make genetic heterogeneity of variance a less stable trait over time and space.

Regressive logistic and proportional hazards disease models for within-family analyses of measured genotypes, with application to a CYP17 polymorphism and breast cancer

Various statistical methods have been proposed to evaluate associations between measured genetic variants and disease, including some using family designs. For breast cancer and rare variants, we applied a modified segregation analysis method that uses the population cancer incidence and population-based case families in which a mutation is known to be segregating. Here we extend the method to a common polymorphism, and use a regressive logistic approach to model familial aggregation by conditioning each individual on their mother's breast cancer history. We considered three models: 1) class A regressive logistic model; 2) age-of-onset regressive logistic model; and 3) proportional hazards familial model. Maximum likelihood estimates were calculated using the software MENDEL. We applied these methods to data from the Australian Breast Cancer Family Study on the CYP17 5UTR TC MspA1 polymorphism measured for 1,447 case probands, 787 controls, and 213 relatives of case probands found to have the CC genotype. Breast cancer data for first- and second-degree relatives of case probands were used. The three methods gave consistent estimates. The best-fitting model involved a recessive inheritance, with homozygotes being at an increased risk of 47% (95% CI, 28-68%). The cumulative risk of the disease up to age 70 years was estimated to be 10% or 22% for a CYP17 homozygote whose mother was unaffected or affected, respectively. This analytical approach is well-suited to the data that arise from population-based case-control-family studies, in which cases, controls and relatives are studied, and genotype is measured for some but not all subjects.

A Space of One's Own: Women's Magazine Consumption Within Family Life

This is a study of women's magazine consumption in the home. It explores issues of time and space, and addresses the importance the women who took part in the study place on magazine consumption in their lives, given the 'juggling' lifestyles experiences by most of them. The study reveals family life to be a landscape within which these women carve out what they perceive as valuable and rare time and space for themselves. The authors argue that in contemporary life women's magazines play a key part in the quest for me-time and time away from others, in both a tangible and experiential sense.

L’adoption intrafamiliale réalisée en Haïti par des Haïtiens québécois vivant à Montréal

La protection des enfants dans les pays en développement constitue encore aujourd’hui une problématique qui continue à alimenter la préoccupation et des débats sur l’avenir des enfants à l’échelle nationale et internationale. En dépit des interventions répétées des organismes internationaux œuvrant dans le domaine de la protection des enfants à travers le monde, les conditions socioéconomiques de millions d’enfants ne cessent d’empirer, laissant ainsi leur avenir dans une incertitude accablante. Le souci de secourir ces enfants a ouvert la voie à l’amplification du phénomène d’adoption internationale qui témoigne d’une forme de «solidarité» internationale en faveur des enfants à travers le monde mais qui finit par s’imposer comme une forme de protection sociale qui transcende les frontières nationales. En Haïti, la précarité des conditions de vie a permis la mise en action d’un ensemble de stratégies d’entraide se reposant sur des liens communautaires forts qui se veut une sorte de soupape pour amortir les impacts sur les membres de la famille, mais qui s’étend parfois sur toute la communauté. Dans cette dynamique, l’enfant bénéficie d’une attention soutenue. Ainsi, certains membres de la diaspora haïtienne en Amérique du Nord, plus précisément à Montréal ont procédé à l’adoption dans leur famille élargie en Haïti. L’objectif de cette recherche est donc de dégager une appréhension de l’adoption intrafamiliale en Haïti, plus particulièrement celle réalisée par des haïtiens vivants à Montréal. Mais de manière spécifique, nous visons à : 1) comprendre la nature des décisions d’adopter et sa spécificité en contexte d’adoption intrafamiliale chez les adoptants québécois originaires d’Haïti, 2) établir les étapes et le contexte des démarches d’adoption qui caractérisent les projets des adoptants haïtiens québécois et 3) comprendre dans quelle mesure la protection des enfants fait partie du désir d’adopter chez ces adoptants en dégageant leur point de vue. Cette recherche nous a permis de comprendre que l’adoption intrafamiliale en Haïti est marquée par une grande diversité de motivations tels que le désir d’enfants, le sauvetage des enfants, la redevance sociale, la réussite sociale de l’enfant, l’accès à l’éducation, le désengagement social, le souci de maintenir à distance l’esprit de clan et le don d’enfants. Si ces motifs visent pour la plupart à la protection de l’enfant, ils sont aussi en lien avec la culture haïtienne qui voit dans celui-ci une véritable lueur d’espoir pour l’amélioration des conditions de vie des parents dans leurs vieux jours.

Entrepreneurship and family firms : growth and survival

Family businesses dominate in a majority of economies (Astrachan and Shanker, 2003; Chrisman, Chua, and Sharma, 2005; Morck and Yeung, 2004). As entrepreneurial activities have been shown to be central to economic growth it is essential that family businesses, irrespective of ownership patterns, not only survive but also grow thus growing the economy overall. While a great deal is known about entrepreneurial activities and a body of knowledge is being developed in relation to entrepreneurial processes in family firms, more needs to be understood in relation to the dynamics of entrepreneurial activities at the individual family firm level. One area of particular interest is the dynamics within the business and the family and how these dynamics impact upon entrepreneurial activities. Specifically how relationships between and among family members engaged in the business can interact with professional non-family member senior executives. The senior executives can actively use their positions in such ways that initiatives suggested by family members are less successful than they might be. This paper addresses how ‘family’ aspects of a business can assist or impede the entrepreneurial activities of individuals. It takes into account some of the unique features of family businesses – such as the importance of ‘familiness’ as a competitive advantage; the direct links between ownership and control of a business and the recognition (often implicit) that individuals in families do make a difference to how the business functions (Habbershon and Williams, 1999, Sharma, 2004; and Tokarczyk, Hansen Green, and Down, 2007). This emphasis on individuals in families fits well with the idea of entrepreneur as individual, as expressed by Schumpeter (1934), Baumol et al (2007). The theoretical approach that adopted to explore the dynamics of processes occurring within family firms is structuration theory combined with a theory of embeddeness (Dacin, Ventresca and Beal, 1999; Giddens, 1979, 1984, Jack and Anderson, 2002; and Sarason, Dean and Dillard, 2006).

The social orders of family mealtime

This study examined the everyday practices of families within the context of family mealtime to investigate how members accomplished mealtime interactions. Using an ethnomethodological approach, conversation analysis and membership categorization analysis, the study investigated the interactional resources that family members used to assemble their social orders moment by moment during family mealtimes. While there is interest in mealtimes within educational policy, health research and the media, there remain few studies that provide fine-grained detail about how members produce the social activity of having a family meal. Findings from this study contribute empirical understandings about families and family mealtime. Two families with children aged 2 to 10 years were observed as they accomplished their everyday mealtime activities. Data collection took place in the family homes where family members video recorded their naturally occurring mealtimes. Each family was provided with a video camera for a one-month period and they decided which mealtimes they recorded, a method that afforded participants greater agency in the data collection process and made available to the analyst a window into the unfolding of the everyday lives of the families. A total of 14 mealtimes across the two families were recorded, capturing 347 minutes of mealtime interactions. Selected episodes from the data corpus, which includes centralised breakfast and dinnertime episodes, were transcribed using the Jeffersonian system. Three data chapters examine extended sequences of family talk at mealtimes, to show the interactional resources used by members during mealtime interactions. The first data chapter explores multiparty talk to show how the uniqueness of the occasion of having a meal influences turn design. It investigates the ways in which members accomplish two-party talk within a multiparty setting, showing how one child "tells" a funny story to accomplish the drawing together of his brothers as an audience. As well, this chapter identifies the interactional resources used by the mother to cohort her children to accomplish the choralling of grace. The second data chapter draws on sequential and categorical analysis to show how members are mapped to a locally produced membership category. The chapter shows how the mapping of members into particular categories is consequential for social order; for example, aligning members who belong to the membership category "had haircuts" and keeping out those who "did not have haircuts". Additional interactional resources such as echoing, used here to refer to the use of exactly the same words, similar prosody and physical action, and increasing physical closeness, are identified as important to the unfolding talk particularly as a way of accomplishing alignment between the grandmother and grand-daughter. The third and final data analysis chapter examines topical talk during family mealtimes. It explicates how members introduce topics of talk with an orientation to their co-participant and the way in which the take up of a topic is influenced both by the sequential environment in which it is introduced and the sensitivity of the topic. Together, these three data chapters show aspects of how family members participated in family mealtimes. The study contributes four substantive themes that emerged during the analytic process and, as such, the themes reflect what the members were observed to be doing. The first theme identified how family knowledge was relevant and consequential for initiating and sustaining interaction during mealtime with, for example, members buying into the talk of other members or being requested to help out with knowledge about a shared experience. Knowledge about members and their activities was evident with the design of questions evidencing an orientation to coparticipant’s knowledge. The second theme found how members used topic as a resource for social interaction. The third theme concerned the way in which members utilised membership categories for producing and making sense of social action. The fourth theme, evident across all episodes selected for analysis, showed how children’s competence is an ongoing interactional accomplishment as they manipulated interactional resources to manage their participation in family mealtime. The way in which children initiated interactions challenges previous understandings about children’s restricted rights as conversationalists. As well as making a theoretical contribution, the study offers methodological insight by working with families as research participants. The study shows the procedures involved as the study moved from one where the researcher undertook the decisions about what to videorecord to offering this decision making to the families, who chose when and what to videorecord of their mealtime practices. Evident also are the ways in which participants orient both to the video-camera and to the absent researcher. For the duration of the mealtime the video-camera was positioned by the adults as out of bounds to the children; however, it was offered as a "treat" to view after the mealtime was recorded. While situated within family mealtimes and reporting on the experiences of two families, this study illuminates how mealtimes are not just about food and eating; they are social. The study showed the constant and complex work of establishing and maintaining social orders and the rich array of interactional resources that members draw on during family mealtimes. The family’s interactions involved members contributing to building the social orders of family mealtime. With mealtimes occurring in institutional settings involving young children, such as long day care centres and kindergartens, the findings of this study may help educators working with young children to see the rich interactional opportunities mealtimes afford children, the interactional competence that children demonstrate during mealtimes, and the important role/s that adults may assume as co-participants in interactions with children within institutional settings.

Genetic response to combined family selection for improved mean harvest weight in giant freshwater prawn (Macrobrachium rosenbergii) in Vietnam

We estimated genetic changes in body and carcass weight traits in a giant freshwater prawn (GFP) (Macrobrachium rosenbergii) population selected for increased body weight at harvest in Vietnam. The data set consisted of 18,387 individual body and 1730 carcass weight records, as well as full pedigree information collected over four generations. Average selection response (per generation) in body weight at harvest (transformed to square root) estimated as the difference between the Selection line and the Control group was 7.4% calculated from least squares mean (LSMs), 7.0% from estimated breeding values (EBVs) and 4.4% calculated from EBVs between two consecutive generations. Favorable correlated selection responses (estimated from LSMs) were found for other body traits including: total length, cephalothorax length, abdominal length, cephalothorax width, and abdominal width (12.1%, 14.5%, 10.4%, 15.5% and 13.3% over three selection generations, respectively). Data in the second generation of selection showed positive correlated responses for carcass weight traits including: abdominal weight, exoskeleton-off weight, and telson-off weight of 8.8%, 8.6% and 8.8%, respectively. We conclude that body weight at harvest responded well to the application of combined (between and within) family selection and correlated responses in carcass weight traits were favorable.

Family-based associations in measures of psychological distress and quality of life in a cardiac screening clinic for inheritable cardiac diseases: a cross-sectional study

BACKGROUND: Family-based cardiac screening programmes for persons at risk for genetic cardiac diseases are now recommended. However, the psychological wellbeing and health related quality of life (QoL) of such screened patients is poorly understood, especially in younger patients. We sought to examine wellbeing and QoL in a representative group of adults aged 16 and over in a dedicated family cardiac screening clinic.

METHODS: Prospective survey of consecutive consenting patients attending a cardiac screening clinic, over a 12 month period. Data were collected using two health measurement tools: the Short Form 12 (version 2) and the Hospital Anxiety and Depression Scale (HADS), along with baseline demographic and screening visit-related data. The HADS and SF-12v.2 outcomes were compared by age group. Associations with a higher HADS score were examined using logistic regression, with multi-level modelling used to account for the family-based structure of the data.

RESULTS: There was a study response rate of 86.6%, with n=334 patients providing valid HADS data (valid response rate 79.5%), and data on n=316 retained for analysis. One-fifth of patients were aged under 25 (n=61). Younger patients were less likely than older to describe significant depression on their HADS scale (p<0.0001), although there were overall no difference between the prevalence of a significant HADS score between the younger and older age groups (18.0% vs 20.0%, p=0.73). Significant positive associates of a higher HADS score were having lower educational attainment, being single or separated, and being closely related to the family proband. Between-family variance in anxiety and depression scores was greater than within-family variance.

CONCLUSIONS: High levels of anxiety were seen amongst patients attending a family-based cardiac screening clinic.Younger patients also had high rates of clinically significant anxiety. Higher levels of anxiety and depression tends to run in families, and this has implications for family screening and intervention programmes.

An evolutionary theory of the family.

An evolutionary framework for viewing the formation, the stability, the organizational structure, and the social dynamics of biological families is developed. This framework is based upon three conceptual pillars: ecological constraints theory, inclusive fitness theory, and reproductive skew theory. I offer a set of 15 predictions pertaining to living within family groups. The logic of each is discussed, and empirical evidence from family-living vertebrates is summarized. I argue that knowledge of four basic parameters, (i) genetic relatedness, (ii) social dominance, (iii) the benefits of group living, and (iv) the probable success of independent reproduction, can explain many aspects of family life in birds and mammals. I suggest that this evolutionary perspective will provide insights into understanding human family systems as well.

INTERGENERATIONAL SUPPORT AND WELL-BEING OF OLDER ADULTS IN CHANGING FAMILY CONTEXTS

This dissertation consists of three papers that examine the complexities in upward intergenerational support and adult children’s influence on older adults’ health in changing family contexts of America and China. The prevalence of “gray divorce/repartnering ” in later life after age 55 is on the rise in the United States, yet little is known about its effect on intergenerational support. The first paper uses the life course perspective to examine whether gray divorce and repartnering affect support from biological and stepchildren differently than early divorce and repartnering, and how patterns differ by parents’ gender. Massive internal migration in China has led to increased geographic distance between adult children and aging parents, which may have consequences for old age support received by parents. This topic has yet to be thoroughly explored in China, as most studies of intergenerational support to older parents have focused on the role of coresident children or have not considered the interdependence of multiple parent-child dyads in the family. The second paper adopts the within-family differences approach to assess the influence of non-coresident children’s relative living proximity to parents compared to that of their siblings on their provision of support to parents in rural and urban Chinese families. The study also examines how patterns of the impact are moderated by parents’ living arrangement, non-coresident children’s gender, and parents’ provision of support to children. Taking a multigenerational network perspective, the third paper questions if and how adult children’s socioeconomic status (SES) influences older parents’ health in China. It further examines whether health benefits brought by adult children’s socioeconomic attainment are larger for older adults with lower SES and whether one of the mechanisms through which adult children’s SES affects older parents’ health is by changing their health behaviors. These questions are highly relevant in contemporary China, where adult children have experienced substantial gains in SES and play a central role in old age support for parents. In sum, these three papers take the life course, the within-family differences, and the multigenerational network perspective to address the complexities in intergenerational support and older adults’ health in diverse family contexts.

Prevalence and genetic diversity of Blastocystis in family units living in the United States

The human gut is host to a diversity of microorganisms including the single-celled microbial eukaryote Blastocystis. Although Blastocystis has a global distribution, there is dearth of information relating to its prevalence and diversity in many human populations. The mode of Blastocystis transmission to humans is also insufficiently characterised, however, it is speculated to vary between different populations. Here we investigated the incidence and genetic diversity of Blastocystis in a US population and also the possibility of Blastocystis human-human transmission between healthy individuals using family units (N = 50) living in Boulder, Colorado as our sample-set. Ten of the 139 (~ 7%) individuals in our dataset were positive for Blastocystis, nine of whom were adults and one individual belonging to the children/adolescents group. All positive cases were present in different family units. A number of different Blastocystis subtypes (species) were detected with no evidence of mixed infections. The prevalence of Blastocystis in this subset of the US population is comparatively low relative to other industrialised populations investigated to date; however, subtype diversity was largely consistent with that previously reported in studies of European populations. The distribution of Blastocystis within family units indicates that human-human transmission is unlikely to have occurred within families that participated in this study. It is not unexpected that given the world-wide variation in human living conditions and lifestyles between different populations, both the prevalence of Blastocystis and its mode of transmission to humans may vary considerably.

Candidate gene analysis for quantitative traits using the transmission disequilibrium test : the example of the melanocortin 4-receptor in pigs

Population-wide associations between loci due to linkage disequilibrium can be used to map quantitative trait loci (QTL) with high resolution. However, spurious associations between markers and QTL can also arise as a consequence of population stratification. Statistical methods that cannot differentiate between loci associations due to linkage disequilibria from those caused in other ways can render false-positive results. The transmission-disequilibrium test (TDT) is a robust test for detecting QTL. The TDT exploits within-family associations that are not affected by population stratification. However, some TDTs are formulated in a rigid-form, with reduced potential applications. In this study we generalize TDT using mixed linear models to allow greater statistical flexibility. Allelic effects are estimated with two independent parameters: one exploiting the robust within-family information and the other the potentially biased between-family information. A significant difference between these two parameters can be used as evidence for spurious association. This methodology was then used to test the effects of the fourth melanocortin receptor (MC4R) on production traits in the pig. The new analyses supported the previously reported results; i.e., the studied polymorphism is either causal of in very strong linkage disequilibrium with the causal mutation, and provided no evidence for spurious association.