33 research outputs found
The Influence of Caregivers' Gender Attitudes on Adolescents' Health and Well-Being in the Democratic Republic of Congo
Gender norms are social constructs held by communities that dictate the acceptable range of behaviors and roles for men and women. Inequitable gender norms have a negative impact on the health and well-being of adults and children alike. In early adolescence, children become more attuned to their communities’ gender norms. Exposure to humanitarian emergencies, such as armed conflict, exacerbate the health threats of inequitable gender norms by disrupting the social supports necessary for safe and healthy adolescent development. Caregivers are key in socializing children to their communities prevailing gender norms and in buffering against the mental health risks associated with growing up in a humanitarian setting. Limited research has been conducted into the role that caregiver gender attitudes play in the health of adolescents living in a humanitarian setting. This study employs mixed-methods to explore how caregiver gender attitudes are associated with adolescent psychosocial health, nutrition, and school attendance in a sample of adolescent/caregiver dyads (n=375) living in eastern Democratic Republic of Congo.
Adolescents of caregivers with moderately gender equitable attitudes were found to have greater food security than children of caregivers with the least equitable gender attitudes. After stratifying by sex, girls of caregivers with moderately gender equitable attitudes had better food security and girls with caregivers endorsing moderately or the most gender equitable attitudes were found to have better scores on a measure of anxiety and depression than as compared to girls of caregivers with the least equitable gender attitudes. There was an overall trend for adolescents with caregivers classified as moderately gender equitable to have better outcomes across all four measures than adolescents with caregivers classified as having the least or most gender equitable attitudes.
Focus group discussions suggested that differences in girls’ mental health outcomes might differ due to caregivers’ use of control techniques that limit girls’ autonomy and in the frequency that girls witness intimate partner violence. Researchers should examine how the different dimensions of individuals’ gender attitudes affect adolescent health and explore how to prevent families who challenge restrictive gender norms from experiencing the social sanctions resulting from endorsing more gender equitable attitudes.
Advisor:
Nancy E. Glass, PhD, MPH, RN, FAAN
[email protected]
Genome-wide association meta-analysis of age at first cannabis use
Cannabis is one of the most commonly used substances among adolescents and young adults. Earlier age at cannabis initiation is linked to adverse life outcomes including multi-substance use and dependence. This study estimated the heritability of age at first cannabis use and identify associations with genetic variants. A twin-based heritability analysis using 8,055 twins from three cohorts was performed. We then carried-out a genome wide survival meta-analysis of age at first cannabis use in a discovery sample of 24,953 individuals from nine European, North American, and Australian cohorts, and a replication sample of 3,735 individuals. The twin-based heritability for age at first cannabis use was 38% (95% confidence interval [CI] 19-60%). Shared and unique environmental factors explained 39% (95% CI 20-56%) and 22% (95% CI 16-29%). The genome wide survival meta-analysis identified five SNPs on chromosome 16 within the Calcium-transporting ATPase gene (ATP2C2) at P 0.8) with the strongest association at the intronic variant rs1574587 (P=4.09E-09). Gene-based tests of association identified the ATP2C2 gene on 16q24.1 (P=1.33e-06). Although the five SNPs and ATP2C2 did not replicate, ATP2C2 has been associated with cocaine dependence in a previous study. ATP2B2, which is a member of the same calcium signalling pathway, has been previously associated with opioid dependence. SNP-based heritability for age at first cannabis use was non-significant. Age at cannabis initiation appears to be moderately heritable in Western countries, and individual differences in onset can be explained by separate but correlated genetic liabilities. The significant association between age of initiation and ATP2C2 is consistent with the role of calcium signalling mechanisms in substance use disorders
Rare and low-frequency coding variants alter human adult height
Height is a highly heritable, classic polygenic trait with ~700 common associated variants identified so far through genome - wide association studies . Here , we report 83 height - associated coding variants with lower minor allele frequenc ies ( range of 0.1 - 4.8% ) and effects of up to 2 16 cm /allele ( e.g. in IHH , STC2 , AR and CRISPLD2 ) , >10 times the average effect of common variants . In functional follow - up studies, rare height - increasing alleles of STC2 (+1 - 2 cm/allele) compromise d proteolytic inhibition of PAPP - A and increased cleavage of IGFBP - 4 in vitro , resulting in higher bioavailability of insulin - like growth factors . The se 83 height - associated variants overlap genes mutated in monogenic growth disorders and highlight new biological candidates ( e.g. ADAMTS3, IL11RA, NOX4 ) and pathways ( e.g . proteoglycan/ glycosaminoglycan synthesis ) involved in growth . Our results demonstrate that sufficiently large sample sizes can uncover rare and low - frequency variants of moderate to large effect associated with polygenic human phenotypes , and that these variants implicate relevant genes and pathways
A gravitational-wave standard siren measurement of the Hubble constant
On 17 August 2017, the Advanced LIGO 1 and Virgo 2 detectors observed the gravitational-wave event GW170817-a strong signal from the merger of a binary neutron-star system 3 . Less than two seconds after the merger, a γ-ray burst (GRB 170817A) was detected within a region of the sky consistent with the LIGO-Virgo-derived location of the gravitational-wave source 4-6 . This sky region was subsequently observed by optical astronomy facilities 7 , resulting in the identification 8-13 of an optical transient signal within about ten arcseconds of the galaxy NGC 4993. This detection of GW170817 in both gravitational waves and electromagnetic waves represents the first 'multi-messenger' astronomical observation. Such observations enable GW170817 to be used as a 'standard siren' 14-18 (meaning that the absolute distance to the source can be determined directly from the gravitational-wave measurements) to measure the Hubble constant. This quantity represents the local expansion rate of the Universe, sets the overall scale of the Universe and is of fundamental importance to cosmology. Here we report a measurement of the Hubble constant that combines the distance to the source inferred purely from the gravitational-wave signal with the recession velocity inferred from measurements of the redshift using the electromagnetic data. In contrast to previous measurements, ours does not require the use of a cosmic 'distance ladder' 19 : the gravitational-wave analysis can be used to estimate the luminosity distance out to cosmological scales directly, without the use of intermediate astronomical distance measurements. We determine the Hubble constant to be about 70 kilometres per second per megaparsec. This value is consistent with existing measurements 20,21 , while being completely independent of them. Additional standard siren measurements from future gravitationalwave sources will enable the Hubble constant to be constrained to high precision
Genetic association study of childhood aggression across raters, instruments, and age
Childhood aggressive behavior (AGG) has a substantial heritability of around 50%. Here we present a genome-wide association metaanalysis (GWAMA) of childhood AGG, in which all phenotype measures across childhood ages from multiple assessors were included. We analyzed phenotype assessments for a total of 328 935 observations from 87 485 children aged between 1.5 and 18 years, while accounting for sample overlap. We also meta-analyzed within subsets of the data, i.e., within rater, instrument and age. SNP-heritability for the overall meta-analysis AGGoverall was 3.31% (SE= 0.0038). We found no genome-wide significant SNPs for AGGoverall. The gene-based analysis returned three significant genes: ST3GAL3 (P= 1.6E-06), PCDH7 (P= 2.0E-06), and IPO13 (P= 2.5E-06). All three genes have previously been associated with educational traits. Polygenic scores based on our GWAMA significantly predicted aggression in a holdout sample of children (variance explained = 0.44%) and in retrospectively assessed childhood aggression (variance explained = 0.20%). Genetic correlations rg among rater-specific assessment of AGG ranged from rg= 0.46 between self- and teacher-assessment to rg= 0.81 between mother- and teacher-assessment. We obtained moderate-to-strong rgs with selected phenotypes from multiple domains, but hardly with any of the classical biomarkers thought to be associated with AGG. Significant genetic correlations were observed with most psychiatric and psychological traits (range |rg|: 0.19-1.00), except for obsessive-compulsive disorder. Aggression had a negative genetic correlation (rg=∼-0.5) with cognitive traits and age at first birth. Aggression was strongly genetically correlated with smoking phenotypes (range |rg| : 0.46-0.60). The genetic correlations between aggression and psychiatric disorders were weaker for teacher-reported AGG than for mother- and self-reported AGG. The current GWAMA of childhood aggression provides a powerful tool to interrogate the rater-specific genetic etiology of AGG.</p
A História da Alimentação: balizas historiográficas
Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema
A gravitational-wave standard siren measurement of the Hubble constant
The detection of GW170817 (ref. 1) heralds the age of gravitational-wave multi-messenger astronomy, with the observations of gravitational-wave and electromagnetic emission from the same transient source. On 17 August 2017 the network of Advanced Laser Interferometer Gravitational-wave Observatory (LIGO)2 and Virgo3 detectors observed GW170817, a strong signal from the merger of a binary neutron-star system. Less than two seconds after the merger, a γ-ray burst event, GRB 170817A, was detected consistent with the LIGO–Virgo sky localization region4–6). The sky region was subsequently observed by optical astronomy facilities7, resulting in the identification of an optical transient signal within about 10 arcseconds of the galaxy NGC 4993 (refs 8–13). GW170817 can be used as a standard siren14–18, combining the distance inferred purely from the gravitational-wave signal with the recession velocity arising from the electromagnetic data to determine the Hubble constant. This quantity, representing the local expansion rate of the Universe, sets the overall scale of the Universe and is of fundamental importance to cosmology. Our measurements do not require any form of cosmic ‘distance ladder’19; the gravitational-wave analysis directly estimates the luminosity distance out to cosmological scales. Here we report H0 = kilometres per second per megaparsec, which is consistent with existing measurements20,21, while being completely independent of them
Genetic association study of childhood aggression across raters, instruments, and age
Childhood aggressive behavior (AGG) has a substantial heritability of around 50%. Here we present a genome-wide association metaanalysis (GWAMA) of childhood AGG, in which all phenotype measures across childhood ages from multiple assessors were included. We analyzed phenotype assessments for a total of 328 935 observations from 87 485 children aged between 1.5 and 18 years, while accounting for sample overlap. We also meta-analyzed within subsets of the data, i.e., within rater, instrument and age. SNP-heritability for the overall meta-analysis (AGGoverall) was 3.31% (SE= 0.0038). We found no genome-wide significant SNPs for AGG(overall). The gene-based analysis returned three significant genes: ST3GAL3 (P= 1.6E-06), PCDH7 (P= 2.0E-06), and IPO13 (P= 2.5E-06). All three genes have previously been associated with educational traits. Polygenic scores based on our GWAMA significantly predicted aggression in a holdout sample of children (variance explained = 0.44%) and in retrospectively assessed childhood aggression (variance explained = 0.20%). Genetic correlations (rg) among rater-specific assessment of AGG ranged from r(g)= 0.46 between self- and teacher-assessment to r(g)d= 0.81 between mother- and teacher-assessment. We obtained moderate-to-strong rgs with selected phenotypes from multiple domains, but hardly with any of the classical biomarkers thought to be associated with AGG. Significant genetic correlations were observed with most psychiatric and psychological traits (range r(g): 0.19-1.00), except for obsessive-compulsive disorder. Aggression had a negative genetic correlation (r(g)=-0.5) with cognitive traits and age at first birth. Aggression was strongly genetically correlated with smoking phenotypes (range |r(g)| : 0.46-0.60). The genetic correlations between aggression and psychiatric disorders were weaker for teacher-reported AGG than for mother- and self-reported AGG. The current GWAMA of childhood aggression provides a powerful tool to interrogate the rater-specific genetic etiology of AGG.Peer reviewe