SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Adult

183

As vertebrate embryos develop to adulthood, their organs undergo marked changes in size and tissue architecture. The heart acquires muscle mass and matures structurally to fulfil increasing circulatory needs, a process that is incompletely understood. Here we used multicolour clonal analysis to define the contributions of individual cardiomyocytes as the zebrafish heart undergoes morphogenesis from a primitive embryonic structure into its complex adult form. We find that the single-cardiomyocyte-thick wall of the juvenile ventricle forms by lateral expansion of several dozen cardiomyocytes into muscle patches of variable sizes and shapes. As juvenile zebrafish mature into adults, this structure becomes fully enveloped by a new lineage of cortical muscle. Adult cortical muscle originates from a small number of cardiomyocytes–an average of approximately eight per animal–that display clonal dominance reminiscent of stem cell populations. Cortical cardiomyocytes initially emerge from internal myofibres that in rare events breach the juvenile ventricular wall, and then expand over the surface. Our results illuminate the dynamic proliferative behaviours that generate adult cardiac structure, revealing clonal dominance as a key mechanism that shapes a vertebrate organ.

Concepts: Blood, Heart, Structure, Muscle, Cardiac muscle, Organ, Circulatory system, Adult

163

Bochdalek hernia is the most common type of congenital diaphragmatic hernia. It appears frequently in infants but rarely in adults. We present the case of a 50-year-old female han patient with tremendous left-sided congenital posterolateral diaphragmatic hernia (Bochdalek hernia) who also has a pair of supernumerary breasts and pulmonary hypoplasia of the lower-left lobe. The patient had an experience of misdiagnosis and she was treated for bronchitis for one year until being admitted to our hospital. This case study emphasizes the rare presentation of Bochdalek hernia in adults and the necessity of high clinical attention to similar cases.

Concepts: Lung, Patient, Case study, Case, Adult, Congenital diaphragmatic hernia, Diaphragmatic hernia, Bochdalek hernia

139

The central question we addressed was whether mothers' adjustment might vary systematically by the developmental stages of their children. In an Internet-based study of over 2,200 mostly well-educated mothers with children ranging from infants to adults, we examined multiple aspects of mothers' personal well-being, parenting, and perceptions of their children. Uniformly, adjustment indices showed curvilinear patterns across children’s developmental stages, with mothers of middle-schoolers faring the most poorly, and mothers of adult children and infants faring the best. Findings based on children in mutually exclusive age groups-for example, mothers with only (1 or more) infants, preschoolers, and so forth-had larger effect sizes than those based on the age of the mothers' oldest child. In contrast to the recurrent findings based on children’s developmental stages, mothers' adjustment dimensions showed few variations by their children’s gender. Collectively, results of this study suggest that there is value in preventive interventions involving mothers not just in their children’s infancy and preschool years, but also as their children traverse the developmentally challenging years surrounding puberty. (PsycINFO Database Record

Concepts: Infant, The Age, Child, Developmental psychology, Puberty, Human development, Child development, Adult

99

Stress over the lifespan is thought to promote accelerated aging and early disease. Telomere length is a marker of cell aging that appears to be one mediator of this relationship. Telomere length is associated with early adversity and with chronic stressors in adulthood in many studies. Although cumulative lifespan adversity should have bigger impacts than single events, it is also possible that adversity in childhood has larger effects on later life health than adult stressors, as suggested by models of biological embedding in early life. No studies have examined the individual vs. cumulative effects of childhood and adulthood adversities on adult telomere length. Here, we examined the relationship between cumulative childhood and adulthood adversity, adding up a range of severe financial, traumatic, and social exposures, as well as comparing them to each other, in relation to salivary telomere length. We examined 4,598 men and women from the US Health and Retirement Study. Single adversities tended to have nonsignificant relations with telomere length. In adjusted models, lifetime cumulative adversity predicted 6% greater odds of shorter telomere length. This result was mainly due to childhood adversity. In adjusted models for cumulative childhood adversity, the occurrence of each additional childhood event predicted 11% increased odds of having short telomeres. This result appeared mainly because of social/traumatic exposures rather than financial exposures. This study suggests that the shadow of childhood adversity may reach far into later adulthood in part through cellular aging.

Concepts: DNA, Senescence, Biology, Telomere, Adult, Coming of age

87

Examining age, time period, and cohort/generational changes in sexual experience is key to better understanding sociocultural influences on sexuality and relationships. Americans born in the 1980s and 1990s (commonly known as Millennials and iGen) were more likely to report having no sexual partners as adults compared to GenX'ers born in the 1960s and 1970s in the General Social Survey, a nationally representative sample of American adults (N = 26,707). Among those aged 20-24, more than twice as many Millennials born in the 1990s (15 %) had no sexual partners since age 18 compared to GenX'ers born in the 1960s (6 %). Higher rates of sexual inactivity among Millennials and iGen also appeared in analyses using a generalized hierarchical linear modeling technique known as age-period-cohort analysis to control for age and time period effects among adults of all ages. Americans born early in the 20th century also showed elevated rates of adult sexual inactivity. The shift toward higher rates of sexual inactivity among Millennials and iGen'ers was more pronounced among women and absent among Black Americans and those with a college education. Contrary to popular media conceptions of a “hookup generation” more likely to engage in frequent casual sex, a higher percentage of Americans in recent cohorts, particularly Millennials and iGen'ers born in the 1990s, had no sexual partners after age 18.

Concepts: 20th century, Adult

74

In 2015, 3.5% of U.S. adults were current e-cigarette users. Among adult e-cigarette users overall, 58.8% also were current cigarette smokers, 29.8% were former cigarette smokers, and 11.4% had never been cigarette smokers. Among current e-cigarette users aged ≥45 years, 98.7% were either current or former cigarette smokers, and 1.3% had never been cigarette smokers. In contrast, among current e-cigarette users aged 18-24 years, 40.0% had never been cigarette smokers.

Concepts: United States, Smoking, Tobacco, Tobacco smoking, Cigarette, Nicotine, Electronic cigarette, Adult

62

Despite recent increased use of antidepressants in the United States, concerns persist that many adults with depression do not receive treatment, whereas others receive treatments that do not match their level of illness severity.

Concepts: United States, Poverty in the United States, U.S. state, Adult, Economy of the United States, Wall Street Crash of 1929, World War II, Unemployment

51

Middle adolescents' close friendship strength and the degree to which their broader peer group expressed a preference to affiliate with them were examined as predictors of relative change in depressive symptoms, self-worth, and social anxiety symptoms from ages 15 to 25 using multimethod, longitudinal data from 169 adolescents. Close friendship strength in midadolescence predicted relative increases in self-worth and decreases in anxiety and depressive symptoms by early adulthood. Affiliation preference by the broader peer group, in contrast, predicted higher social anxiety by early adulthood. Results are interpreted as suggesting that adolescents who prioritize forming close friendships are better situated to manage key social developmental tasks going forward than adolescents who prioritize attaining preference with many others in their peer milieu.

Concepts: Anxiety, Psychology, Sociology, Adolescence, Adult, Friendship, Adulthood, 2000 albums

51

The parents' phenotype, or the environment they create for their young, can have long-lasting effects on their offspring, with profound evolutionary consequences. Yet virtually no work has considered how such parental effects might change the adaptive value of behavioural traits expressed by offspring upon reaching adulthood. To address this problem, we combined experiments on burying beetles (Nicrophorus vespilloides) with theoretical modelling, and focussed on one adult behavioural trait in particular: the supply of parental care. We manipulated the early life environment and measured the fitness payoffs associated with the supply of parental care when larvae reached maturity. We found that (1) adults that received low levels of care as larvae were less successful at raising larger broods, and suffered greater mortality as a result: they were low quality parents. Furthermore (2) high quality males that raised offspring with low quality females subsequently suffered greater mortality than brothers of equivalent quality, which reared larvae with higher quality females. Our analyses identify three general ways in which parental effects can change the adaptive value of an adult behavioural trait: by influencing the associated fitness benefits and costs; by consequently changing the evolutionary outcome of social interactions; and by modifying the evolutionarily stable expression of behavioural traits that are themselves parental effects.

Concepts: Gene, Natural selection, Evolution, Biology, Parent, Beetle, Adult, Burying beetle

49

Persistence, above and beyond IQ, is associated with long-term academic outcomes. To look at the effect of adult models on infants' persistence, we conducted an experiment in which 15-month-olds were assigned to one of three conditions: an Effort condition in which they saw an adult try repeatedly, using various methods, to achieve each of two different goals; a No Effort condition in which the adult achieved the goals effortlessly; or a Baseline condition. Infants were then given a difficult, novel task. Across an initial study and two preregistered experiments (N = 262), infants in the Effort condition made more attempts to achieve the goal than did infants in the other conditions. Pedagogical cues modulated the effect. The results suggest that adult models causally affect infants' persistence and that infants can generalize the value of persistence to novel tasks.

Concepts: Causality, Stanford prison experiment, Affect, Experiment, Task, American football, Adult, Goal