Improving Statistical Rigor in Animal Aging Research by Addressing Clustering and Nesting Effects: Illustration with the National Institute on Aging's Intervention Testing Program Data.

Clustering effects, such as those introduced by housing animals in shared cages, are often overlooked in preclinical lifespan studies, despite their potential to distort variance estimates and inflate Type I error rates, leading to misleading conclusions. This methodological oversight reduces statistical rigor and may undermine the reliability of findings. To address this gap, the current study examines the impact of accounting for clustering and nesting effects on lifespan analyses by comparing the results of statistical models which both account for and ignore these effects.

Lability in parent-child warmth and hostility and adolescent externalizing behaviors.

Both longer term developmental changes (increases in hostility, decreases in warmth) and lability (year-to-year fluctuations) in parent-child relationship quality across childhood and adolescence have been linked to adolescent externalizing behaviors. Using a prospective longitudinal study of 561 children who were adopted into nonrelative families at birth (57% male, 56% White, 19% multiracial, 13% Black, 11% Hispanic) where parental warmth and hostility reflect environmental influences or child-evoked reactions, we examined associations between parent-child relationship measures and externalizing behaviors at age 11 and across adolescence (i.e.

Intergenerational transmission of comorbid internalizing and externalizing psychopathology at age 11: Evidence from an adoption design for general transmission of comorbidity rather than homotypic transmission.

Psychopathology is intergenerationally transmitted through both genetic and environmental mechanisms via heterotypic (cross-domain), homotypic (domain-specific), and general (e.g., "p-factor") pathways.

Early risk for child externalising symptoms: Examining genetic, prenatal, temperamental and parental influences.

This study utilized the Early Growth and Development Study (N = 561 adoptive children; 57.2% male, 55.3% White), a study of children adopted at birth, to examine heritable (birth parent psychopathology) and prenatal risk (prenatal maternal distress and smoking during pregnancy), infant negative affectivity, adoptive parent over-reactivity and warmth as independent predictors of childhood externalizing symptoms.

Prenatal programming of developmental trajectories for obesity risk and early pubertal timing.

The thrifty phenotype and fetal overnutrition hypotheses are two developmental hypotheses that originated from the (DOHaD) perspective. The DOHaD posits that exposures experienced prenatally and early in life may influence health outcomes through altering form and function of internal organs related to metabolic processes. Obesity risk and early pubertal timing might be influenced by similar mechanisms.

Analysis of Early-Life Growth and Age at Pubertal Onset in US Children.

Importance: Earlier pubertal onset may be associated with an increased risk of chronic diseases. However, the extent to which growth in the first 5 years of life-an important developmental life stage that lays the foundation for later health outcomes-is associated with pubertal onset remains understudied.

Objective: To assess whether changes in weight, length or height, and body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) during the first 5 years of life are associated with earlier pubertal onset.

Surviving winter on the Qinghai-Tibetan Plateau: Pikas suppress energy demands and exploit yak feces to survive winter.

The Qinghai-Tibetan Plateau, with low precipitation, low oxygen partial pressure, and temperatures routinely dropping below -30 °C in winter, presents several physiological challenges to its fauna. Yet it is home to many endemic mammalian species, including the plateau pika (). How these small animals that are incapable of hibernation survive the winter is an enigma.

Assay validation of hair androgens across the menstrual cycle.

Introduction: Saliva is a common noninvasive biofluid for measuring stress and sex hormones, yet one pressing limitation is that salivary hormones fluctuate momentarily, daily, and (for girls) across the menstrual cycle. Hair steroid assays are thought to provide a cumulative index which collapses across hormonal variability, potentially eliminating the confound of daily and menstrual cyclicity and thereby reflecting individual differences in average hormone levels. Here we seek to validate a hair bioassay methodology and test whether hair androgens accurately measure long-term, stable androgen levels in emerging adult women across two menstrual cycles.