RESUMO
One long-standing analytic approach in adoption studies is to examine correlations between features of adoptive homes and outcomes of adopted children (hereafter termed 'measured environment correlations') to illuminate environmental influences on those associations. Although results from such studies have almost uniformly suggested modest environmental influences on adopted children's academic achievement, other work has indicated that adopted children's achievement is routinely higher than that of their reared-apart family members, often substantially so. We sought to understand this discrepancy. We examined academic achievement and literacy-promotive features of the home in 424 yoked adoptive/biological families participating in the Early Growth and Development Study (EGDS; i.e., adopted children, adoptive mothers, birth mothers, and biological siblings of the adopted children remaining in the birth homes) using an exhaustive modeling approach. Results indicated that, as anticipated, adopted children scored up to a full standard deviation higher on standardized achievement tests relative to their birth mothers and reared-apart biological siblings. Moreover, these achievement differences were associated with differences in the literacy-promotive features of the adoptive and birth family homes, despite minimal measured environment correlations within adoptive families. A subsequent simulation study highlighted noise in measured environmental variables as an explanation for the decreased utility of measured environment correlations. We conclude that the field's heavy focus on measured environment correlations within adoptive families may have obscured detection of specific environmental effects on youth outcomes, and that future adoption studies should supplement their measured environment analyses with mean differences between reared-apart relatives.
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Sucesso Acadêmico , Criança , Feminino , Adolescente , Humanos , Adoção , Mães , Irmãos , EscolaridadeRESUMO
Few tract-based spatial statistics (TBSS) studies have investigated the relations between intelligence and white matter microstructure in healthy (young) adults, and those have yielded mixed observations, yet white matter is fundamental for efficient and accurate information transfer throughout the human brain. We used a multicenter approach to identify white matter regions that show replicable structure-function associations, employing data from 4 independent samples comprising over 2000 healthy participants. TBSS indicated 188 voxels exhibited significant positive associations between g factor scores and fractional anisotropy (FA) in all 4 data sets. Replicable voxels formed 3 clusters, located around the left-hemispheric forceps minor, superior longitudinal fasciculus, and cingulum-cingulate gyrus with extensions into their surrounding areas (anterior thalamic radiation, inferior fronto-occipital fasciculus). Our results suggested that individual differences in general intelligence are robustly associated with white matter FA in specific fiber bundles distributed across the brain, consistent with the Parieto-Frontal Integration Theory of intelligence. Three possible reasons higher FA values might create links with higher g are faster information processing due to greater myelination, more direct information processing due to parallel, homogenous fiber orientation distributions, or more parallel information processing due to greater axon density.
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Substância Branca , Adulto , Humanos , Substância Branca/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Encéfalo/diagnóstico por imagem , Inteligência , AnisotropiaRESUMO
OBJECTIVES: To evaluate temporal dynamics between loneliness and both objective and subjective health (i.e. functional impairment and self-rated health) in mid- to late-adulthood. METHOD: We applied bivariate dual-change-score models to longitudinal data from 3 Swedish twin studies (N = 1,939) to explore dynamic associations between loneliness and health across 3 age ranges (50-69, 70-81, and 82+ years) to investigate whether associations between loneliness and health change with age due to increasing incidence of chronic health conditions and bereavement. RESULTS: Results showed bidirectional associations between loneliness and both objective and subjective health, with adverse impacts of loneliness observed on subsequent subjective and objective health beginning at age 70. Associations between health and subsequent loneliness were observed after age 82 and varied for subjective and objective health, with subjective health associated with less loneliness and objective health associated with greater loneliness. CONCLUSIONS: Our results indicate dynamic associations between loneliness and health with age in mid- to late-adulthood, with earlier impacts of loneliness on health and later impacts of health on loneliness that vary for objective and subjective measures of health. These findings suggest impacts of health on loneliness may arise later in life when worsening health or mobility interfere with social interaction.
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Autoavaliação Diagnóstica , Solidão , Humanos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Longitudinais , Interação SocialRESUMO
Associations between personality traits and life outcomes are usually studied using the Big Five domains and, occasionally, their facets. But recent research suggests these associations may be driven by the items (reflecting personality nuances) chosen to measure these traits. Using a large dataset (N = 6126), we examined associations with 53 self-reported outcomes using domains, facets and items (markers for nuances), training and validating models in different sample partitions. Facets better predicted outcomes than domains (on average, 18.0% versus 16.6% of variance explained), but items provided the most accurate predictions (on average 20.9%). Removing domain and facet variance from items had no effect on their predictive validity, suggesting that outcome-related information was often in items' unique variances (i.e., nuance-specific). Item-based prediction also showed the highest discriminant validity. These observations, replicating previous findings, suggest that personality traits' valid associations with outcomes are often driven by narrow personality nuances.
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Transtornos da Personalidade , Personalidade , Humanos , Inventário de Personalidade , Fenótipo , AutorrelatoRESUMO
Education has been suggested to be possibly the most consistent, robust, and durable method available for raising intelligence, but little is known about the genetic and environmental interplay underlying this association. Therefore, we investigated how school achievement, as measured by grade point average in lower secondary school at 15 years of age, moderated intelligence variation in young adulthood. The sample consisted of all Danish male twin pairs who had left lower secondary school since 2002 and appeared, typically at age 18, before a draft board through 2015 (N = 2660). Shared environmental variance unique to intelligence (10% of total variance) was found to be greater among individuals with poor school achievement. However, school achievement did not moderate the genetic influences or the non-shared environmental influences on intelligence. We discuss the implications of this in light of the constraints imposed by the statistical models we used.
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Educação/métodos , Inteligência/fisiologia , Sucesso Acadêmico , Estudos de Coortes , Dinamarca , Escolaridade , Humanos , Inteligência/genética , Masculino , Instituições Acadêmicas , Meio Social , Gêmeos/genética , Adulto JovemRESUMO
We investigated intergenerational educational and occupational mobility in a sample of 2,594 adult offspring and 2,530 of their parents. Participants completed assessments of general cognitive ability and five noncognitive factors related to social achievement; 88% were also genotyped, allowing computation of educational-attainment polygenic scores. Most offspring were socially mobile. Offspring who scored at least 1 standard deviation higher than their parents on both cognitive and noncognitive measures rarely moved down and frequently moved up. Polygenic scores were also associated with social mobility. Inheritance of a favorable subset of parent alleles was associated with moving up, and inheritance of an unfavorable subset was associated with moving down. Parents' education did not moderate the association of offspring's skill with mobility, suggesting that low-skilled offspring from advantaged homes were not protected from downward mobility. These data suggest that cognitive and noncognitive skills as well as genetic factors contribute to the reordering of social standing that takes place across generations.
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Filhos Adultos/psicologia , Cognição/fisiologia , Escolaridade , Relação entre Gerações , Mobilidade Social , Sucesso Acadêmico , Adolescente , Feminino , Humanos , Masculino , Herança Multifatorial , Pais/psicologiaRESUMO
BACKGROUND: In 2009 the USDA's Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) updated the food packages provided to participants. OBJECTIVES: This study investigates associations between WIC participation and nutrients and food groups consumed using data from the Feeding Infants and Toddlers Study's 2008 and 2016 nationwide, cross-sectional surveys of children <4 y, weighted to be representative of the US population. METHODS: The study data included 2892 children aged 6-47.9 mo in 2008 and 2635 in 2016. Differences were analyzed by WIC participation, survey year, and child age (infants 6-11.9 mo old, toddlers 12-23.9 mo old, preschoolers 24-47.9 mo old). Usual nutrient intake distributions were estimated using National Cancer Institute methodology. Daily food group consumption differences were tested via multivariate regression. All analyses controlled for income. RESULTS: In 2016 18.6% of infants had iron intakes below the estimated average requirement (EAR), compared to 7.6% in 2008; 87% of WIC infants met the EAR, compared with 69% of non-WIC infants. In 2016 37% of WIC preschoolers met saturated fat guidelines, compared with 25% in 2008; in both years, fewer than one-third of non-WIC preschoolers met the guidelines. More WIC infants than non-WIC infants consumed infant cereals in 2016 (58% compared with 45%, respectively). More WIC infants ate vegetables daily in 2016 than in 2008 (74% compared with 59%, respectively). In 2016, as compared with 2008, more WIC infants consumed baby-food vegetables (55% compared with 29%, respectively) and fruits (56% compared with 41%, respectively). In 2016 47% of WIC preschoolers drank low-fat milk, compared with 19% of non-WIC preschoolers. CONCLUSIONS: Infant iron intakes are concerning, although more WIC infants meet the EAR. WIC infants' vegetable intakes have improved; baby-food vegetables have become important contributors to their intakes. In 2016 WIC children were more likely than non-WIC children to shift to lower-fat milks at 2 y of age, likely contributing to lower saturated fat intakes.
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Inquéritos sobre Dietas , Comportamento Alimentar , Assistência Alimentar , Adulto , Pré-Escolar , Estudos Transversais , Dieta/estatística & dados numéricos , Suplementos Nutricionais/estatística & dados numéricos , Ingestão de Energia , Feminino , Humanos , Renda , Lactente , Masculino , Necessidades Nutricionais , Fatores de TempoRESUMO
Studies often report beneficial effects of physical exercise on depression symptomatology, both in clinical and community samples. In clinical samples, effects are observed using physical exercise as primary treatment and supplement to antidepressant medications and/or psychotherapies. Magnitudes vary with sample characteristics, exercise measure, and study rigor. Both propensity to exercise and vulnerability to depression show genetic influences, suggesting gene-environment interplay. We investigated this in a Danish Twin Registry-based community sample who completed a cycle fitness test and detailed assessments of depression symptomatology and regular exercise engagement that enabled estimates of typical total, intentional exercise-specific, and other metabolic equivalent (MET) expenditures. All exercise-related measures correlated negatively with depression symptomatology (- .07 to - .19). Genetic variance was lower at higher levels of cycle fitness, with genetic and shared environmental correlations of - .50 and 1.0, respectively. Nonshared environmental variance in depression was lower at higher levels of total MET, with no indications of genetic or environmental covariance. Being physically active and/or fit tended to prevent depression, apparently because fewer participants with higher levels of activity and fitness reported high depression symptomatology. This was driven by nonshared environmental influences on activity but genetic influences on physical fitness. Genetic correlation suggested people less genetically inclined toward physical fitness may also be genetically vulnerable to depression, possibly because inertia impedes activity but also possibly due to social pressures to be fit. Exercise programs for general well-being should emphasize participation, not performance level or fitness. We discuss possible interrelations between fitness aptitude and metabolism.
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Depressão/genética , Exercício Físico , Interação Gene-Ambiente , Aptidão Física , Adolescente , Adulto , Idoso , Depressão/terapia , Resistência à Doença/genética , Terapia por Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Gêmeos/genética , Adulto JovemRESUMO
BACKGROUND: Reading is important for children's success in school and beyond, yet many adolescents fail to reach expected levels of proficiency. This highlights the need to better understand the factors that influence reading effectiveness over time, including genes and environment. Greater expression of genetic influence on first- and second-grade reading fluency has been observed in higher quality classroom reading environments. To what degree this early environment continues to influence genetic and other environmental influences on later reading is unknown and was tested in this study. METHODS: The quality of the early classroom reading environment was approximated by gains in oral reading fluency (ORF) across the school year among first- or second-grade classmates of 546 MZ and 1,016 DZ twin children (mean age = 7.13 years; SD = 0.45) who had reading comprehension scores from a state-wide mandatory test in school year 2013-2014 when most twin pairs were in seventh to tenth grade (mean age = 14.41; SD = 1.13) in a variable called Class ORF Gain. Biometrical models were fit to the data to assess whether Class ORF Gain moderated the genetic, shared environmental and/or nonshared environmental variance associated with adolescent reading comprehension. RESULTS: Class ORF Gain moderated shared environmental influences on reading comprehension 6-9 years later. When early classroom reading gains were poor, variability in reading comprehension in adolescence was high and was associated largely with shared environmental influences. When early classroom reading gains were good, overall and shared environmentally influenced variability in adolescent reading comprehension was lower so that genetic influences were most relevant in explaining that variability. CONCLUSIONS: Our findings suggested that classroom reading environment experienced when children were learning to read had a lasting influence on the factors underlying variability in later reading effectiveness.
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Compreensão , Interação Gene-Ambiente , Psicologia do Adolescente , Leitura , Gêmeos/genética , Gêmeos/psicologia , Adolescente , Feminino , Humanos , Aprendizagem , Masculino , Instituições AcadêmicasRESUMO
The decline of working memory (WM) is a common feature of general cognitive decline, and visual and verbal WM capacity appear to decline at different rates with age. Visual material may be remembered via verbal codes or visual traces, or both. Souza and Skóra, Cognition, 166, 277-297 (2017) found that labeling boosted memory in younger adults by activating categorical visual long-term memory (LTM) knowledge. Here, we replicated this and tested whether it held in healthy older adults. We compared performance in silence, under instructed overt labeling (participants were asked to say color names out loud), and articulatory suppression (repeating irrelevant syllables to prevent labeling) in the delayed estimation paradigm. Overt labeling improved memory performance in both age groups. However, comparing the effect of overt labeling and suppression on the number of coarse, categorical representations in the two age groups suggested that older adults used verbal labels subvocally more than younger adults, when performing the task in silence. Older adults also appeared to benefit from labels differently than younger adults. In younger adults labeling appeared to improve visual, continuous memory, suggesting that labels activated visual LTM representations. However, for older adults, labels did not appear to enhance visual, continuous representations, but instead boosted memory via additional verbal (categorical) memory traces. These results challenged the assumption that visual memory paradigms measure the same cognitive ability in younger and older adults, and highlighted the importance of controlling differences in age-related strategic preferences in visual memory tasks.
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Envelhecimento Cognitivo , Idoso , Cognição , Humanos , Memória de Curto Prazo , Rememoração MentalRESUMO
PURPOSE: The aim of this study was to determine the feasibility of developing and implementing a brief nurse-delivered tobacco intervention in an outpatient surgical practice. DESIGN AND METHODS: Initial formative work used a survey and focus groups to determine knowledge, attitudes, and practices of perioperative nurses working in three outpatient surgical practices regarding smoking use and cessation. Based on this work, a brief intervention was designed and implemented in one of the three practices. The documentation of tobacco use and intervention elements was assessed both immediately and approximately 9 months after implementation. FINDINGS: Formative work identified not only several barriers to implementation and little current activity but also favorable attitudes toward interventions. Implementation improved self-efficacy for intervention delivery and compliance with documentation of intervention elements that was sustained for at least 9 months. CONCLUSIONS: Our results suggest that it is feasible for perioperative nurses to play an important role in the delivery of perioperative tobacco interventions.
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Comportamentos Relacionados com a Saúde , Pacientes Ambulatoriais , Abandono do Uso de Tabaco/métodos , Estudos de Viabilidade , Humanos , Inquéritos e Questionários , Uso de TabacoRESUMO
Increasing obesity is a world-wide health concern. Its most commonly used indicator, body mass index (BMI), consistently shows considerable genetic and shared environmental variance throughout life, the latter particularly in youth. Several adult studies have observed less total and genetically influenced variance with higher attained SES. These studies offer clues about sources of the 'obesity epidemic' but analogous youth studies of SES-of-origin are needed. Genetic and environmental influences and moderating effects of SES may vary in countries with different health policies, lifestyles, and degrees/sources of social inequality, offering further clues to the sources of the obesity epidemic. We examined SES-of-origin moderation of BMI variance in the German TwinLife study's cohorts assessed around ages 5, 11, 17, and 23-24, and in the Minnesota Twin Family Study's (MTFS) 11- and 17-year-old birth cohorts assessed longitudinally around ages 11, 17, and 23-24, comparing male and female twins and their parents. Age for age, both sexes' means and variances were greater in MTFS than in TwinLife. We observed that SES generally moderated genetic influences, more strongly in females, similar to most adult studies of attained-SES moderation of BMI. We interpreted differences in our SES-of-origin observations in light of inevitably-missing covariance between SES-of-origin and BMI in the models, mother-father and parent-offspring BMI correlations, and parental attained-SES-BMI correlations. We suggest that one source of the present obesity epidemic is social change that amplifies expression of genes both constraining SES attainment and facilitating weight gain.
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Índice de Massa Corporal , Obesidade/etiologia , Classe Social , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Alemanha , Humanos , Lactente , Masculino , Minnesota , Pais , Aumento de PesoRESUMO
Background: USDA's Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) provides expert-chosen supplemental foods to improve the diets and health of low-income infants and children <5 y of age, but dietary behaviors of WIC participants are not well characterized. Objective: The purpose of this analysis was to examine differences in food consumption patterns between WIC participants and nonparticipants. Methods: FITS 2016 is a nationwide cross-sectional study of children <4 y (n = 3235). Data were weighted to provide US population-representative results. Children were categorized as WIC participants or nonparticipants, with the latter divided into lower- and higher-income nonparticipants. Group differences were assessed via the Wald test (demographics) and Rao-Scott modified chi-square test (breastfeeding prevalence). Differences in percentage consuming WIC-provided and selected other foods between WIC participants and nonparticipants were evaluated with the use of ORs and 95% CIs. Results: WIC infants were less likely to breastfeed than were higher-income nonparticipants at 0-5.9 mo (45% compared with 74%) and less likely than both nonparticipant groups at 6-11.9 mo (30% compared with 49-60%). WIC 6- to 11.9-mo-olds were more likely to consume infant cereals and vegetables than were lower-income nonparticipants. WIC 12 to 23.9-mo-olds were more likely to drink whole milk (which WIC provides at this age) than were nonparticipants (72% compared with 59-64%), whereas WIC participants 24-47.9 mo were more likely to drink low- and nonfat milks (which WIC provides at this age) than were nonparticipants (45% compared with 13-22%). WIC participants 6-47.9 mo were more likely to drink juice than were nonparticipants. Conclusions: Continued improvements in early dietary patterns are warranted for WIC and non-WIC children. Breastfeeding among WIC participants is a continuing challenge. Findings suggest that baby-food cereals, vegetables, and fruits (all provided by WIC) contribute importantly to WIC infants' diets, whereas WIC children are more likely to use lower-fat milks after 2 y of age than are non-WIC participants.
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Saúde da Criança , Dieta , Comportamento Alimentar , Assistência Alimentar , Saúde do Lactente , Pobreza , Animais , Pré-Escolar , Estudos Transversais , Inquéritos sobre Dietas , Feminino , Humanos , Renda , Lactente , Alimentos Infantis , Recém-Nascido , Masculino , Leite , Razão de Chances , Estados UnidosRESUMO
Age moderation of genetic and environmental contributions to Digits Forward, Digits Backward, Block Design, Symbol Digit, Vocabulary, and Synonyms was investigated in a sample of 14,534 twins aged 26 to 98 years. The Interplay of Genes and Environment across Multiple Studies (IGEMS) consortium contributed the sample, which represents nine studies from three countries (USA, Denmark, and Sweden). Average test performance was lower in successively older age groups for all tests. Significant age moderation of additive genetic, shared environmental, and non-shared environmental variance components was observed, but the pattern varied by test. The genetic contribution to phenotypic variance across age was smaller for both Digit Span tests, greater for Synonyms, and stable for Block Design and Symbol Digit. The non-shared environmental contribution was greater with age for the Digit Span tests and Block Design, while the shared environmental component was small for all tests, often more so with age. Vocabulary showed similar age-moderation patterns as Synonyms, but these effects were nonsignificant. Findings are discussed in the context of theories of cognitive aging.
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Educational attainment in adolescence is of paramount importance for attaining higher education and for shaping subsequent life chances. Sociological accounts focus on the role of differences in socioeconomic resources in intergenerational reproduction of educational inequalities. These often disregard the intergenerational transmission of cognitive ability and the importance of children's cognitive ability to educational attainment. Psychological perspectives stress the importance of cognitive ability for educational attainment but underemphasize potentially different roles of specific socioeconomic resources in shaping educational outcomes, as well as individual differences in cognitive ability. By integrating two strands of research, a clearer picture of the pathways linking the family of origin, cognitive ability, and early educational outcomes can be reached. Using the population-based TwinLife study in Germany, we investigated multidimensional pathways linking parental socioeconomic position to their children's cognitive ability and academic track attendance in the secondary school. The sample included twins (N = 4008), respectively ages 11 and 17, and siblings (N = 801). We observed strong genetic influences on cognitive ability, whereas shared environmental influences were much more important for academic tracking. In multilevel analyses, separate dimensions of socioeconomic resources influenced child cognitive ability, controlling parental cognitive ability. Controlling adolescent cognitive ability and parental cognitive ability, parental socioeconomic resources also directly affected track attendance. This indicated that it is crucial to investigate the intertwined influences on educational outcomes in adolescence of both cognitive ability and the characteristics of the family of origin.
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Sucesso Acadêmico , Logro , Comportamento do Adolescente/psicologia , Cognição , Adolescente , Criança , Escolaridade , Feminino , Alemanha , Humanos , Masculino , Pais/psicologia , Instituições Acadêmicas , Classe SocialRESUMO
Estimates of gene-environment interactions (GxE) in behavior genetic models depend on how a phenotype is scaled. Inappropriately scaled phenotypes result in biased estimates of GxE and can sometimes even suggest GxE in the direction opposite to its true direction. Previously proposed solutions are mathematically complex, computationally demanding and may prove impractical for the substantive researcher. We, therefore, evaluated two simple-to-use alternatives: (1) straightforward non-linear transformation of sum scores and (2) factor scores from an appropriate item response theory (IRT) model. Within Purcell's (2002) GxM framework, both alternatives provided less biased parameter estimates, and improved false and true positive rates than using a raw sum score. These approaches are, therefore, recommended over using raw sum scores in tests of GxE. Circumstances under which IRT factor scores versus transformed sum scores should be preferred are discussed.
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Interação Gene-Ambiente , Modelos Genéticos , Agressão , Simulação por Computador , Feminino , Humanos , Inteligência , Masculino , FenótipoRESUMO
From the IGEMS Consortium, data were available from 26,579 individuals aged 23 to 102 years on 3 subjective health items: self-rated health (SRH), health compared to others (COMP), and impact of health on activities (ACT). Marital status was a marker of environmental resources that may moderate genetic and environmental influences on subjective health. Results differed for the 3 subjective health items, indicating that they do not tap the same construct. Although there was little impact of marital status on variance components for women, marital status was a significant modifier of variance in all 3 subjective health measures for men. For both SRH and ACT, single men demonstrated greater shared and nonshared environmental variance than married men. For the COMP variable, genetic variance was greater for single men vs. married men. Results suggest gender differences in the role of marriage as a source of resources that are associated with subjective health.
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Age-related decline in grip strength predicts later life disability, frailty, lower well-being and cognitive change. While grip strength is heritable, genetic influence on change in grip strength has been relatively ignored, with non-shared environmental influence identified as the primary contributor in a single longitudinal study. The extent to which gene-environment interplay, particularly gene-environment interactions, contributes to grip trajectories has yet to be examined. We considered longitudinal grip strength measurements in seven twin studies of aging in the Interplay of Genes and Environment across Multiple Studies consortium. Growth curve parameters were estimated for same-sex pairs, aged 34-99 (N = 10,681). Fisher's test for mixture distribution of within-monozygotic twin-pair differences (N = 1724) was performed on growth curve parameters. We observed significant gene-environment interaction on grip strength trajectories. Finally, we compared the variability of within-pair differences of growth curve parameters by APOE haplotypes. Though not statistically significant, the results suggested that APOE É2É2/É2É3 haplotypes might buffer environmental influences on grip strength trajectories.
Assuntos
Força da Mão/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Apolipoproteínas E/genética , Meio Ambiente , Feminino , Interação Gene-Ambiente , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Gêmeos Monozigóticos/genéticaRESUMO
Root lesion nematodes (Pratylenchus spp.) hinder dryland wheat production worldwide. Montana, a leading U.S. wheat production region, has climatic conditions favorable for Pratylenchus spp. A 2006-2007 statewide soil survey revealed damaging populations of Pratylenchus neglectus, primarily in winter wheat production areas of Montana, whereas P. thornei was not found. Analyses of wheat yields in infested fields revealed negative correlations between yields and spring nematode populations (all P < 0.05 and all R2 > 0.2). Statewide yield losses due to root lesion nematodes were an estimated 12 and 15% for winter wheat in 2006 and 2007, respectively. A subsequent study conducted in 2008 to 2009 revealed significant differences in reproductive success of P. neglectus among seven rotation treatments (P < 0.001). Nematode populations persisted from spring to fall under fallow, barley, pea, and camelina; increased under winter wheat and canola; and decreased under lentil. Populations were sustained through winter following winter wheat and barley but declined following canola, camelina, pea, lentil, and fallow. A screening of 19 barley lines for resistance to P. neglectus revealed significant variation in resistance among entries (P < 0.001), with 'Harrington' barley displaying promising levels of resistance. Development of resistant wheat cultivars remains a principal goal in managing this nematode.