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Multi-omics reveal microbial functional traits and antifungal metabolites associated with lower Pseudogymnoascus destructans loads in bat cave soils.

White-nose syndrome, caused by Pseudogymnoascus destructans (Pd), is a major fungal disease threatening hibernating bats. Cave soils can serve as environmental reservoirs for Pd, yet the microbial and biochemical mechanisms underlying naturally low Pd burdens in some cave environments remain poorly understood. Here, we integrated soil microbiome profiling, metagenomics, metabolomics, multi-omics network analysis, and in vitro validation to investigate the ecological and functional basis of differential Pd loads in hibernating bat caves in Northeast China. The three caves shared cold, humid, and weakly acidic microenvironments, but differed significantly in electrical conductivity, soil water content, nutrient availability, and extracellular enzyme activities. Soil microbial communities showed significant inter-cave variation in composition, diversity, and niche breadth, with stochastic processes contributing substantially to community assembly. Environmental variables, particularly pH and Pd load, were important predictors of microbial community structure. Functional analyses revealed that the low-Pd Gezi Cave was enriched in genes associated with organic carbon degradation, nitrogen input and retention, and secondary metabolism. Metabolomic profiling further identified cave-specific metabolite signatures, among which Biochanin A, 4-Hydroxybenzaldehyde, Vanillin, and Arachidonic acid were negatively correlated with Pd loads. Integrated pathway and network analyses showed that differential genes and metabolites jointly mapped to secondary metabolite biosynthesis, aminobenzoate degradation, and flavonoid degradation pathways, forming a microbe-metabolite-functional gene coupling network involving key taxa such as Rhodococcus, Pseudorhodoplanes, and Rhodoplanes. In vitro assays confirmed that 4-Hydroxybenzaldehyde, Coumarin, and Vanillin inhibited Pd growth. Structural equation modelling further indicated that environmental heterogeneity was associated with variation in Pd loads through microbial functional attributes and metabolite profiles. These findings suggest that naturally low-Pd cave soils are associated with coordinated environmental filtering, microbial functional specialization, and antifungal metabolite production, providing mechanistic insight into microbial and biochemical constraints on Pd persistence in cave reservoirs.

Animals

Relation of infant feeding practices, cigarette smoke exposure, and group child care to the onset and duration of otitis media with effusion in the first two years of life.

The relation of infant feeding practices, cigarette smoke exposure, and group child care to the onset and duration of otitis media with effusion (OME) was evaluated in a cohort of 698 healthy infants prospectively monitored by tympanometry in the home every 2 to 4 weeks until 2 years of age. Except for an experimental group of children who were offered early tube placement, the study children received conventional care from their personal physician or clinic. We used LISREL, a structural equation modeling procedure (computer software), to explore associations between environmental variables and OME onset and duration while controlling for interrelations among the variables. Supine feeding position and early initiation of group child care were associated with earlier onset of OME. Shorter duration of breast-feeding, increased packs of cigarettes smoked per day in the home, and increased hours per week in group child care were associated with an increase in the amount of time with OME during one or more of the age blocks studied (birth to 6, 6 to 12, 12 to 18, and 12 to 24 months). For a decrease in the amount of time with OME during the first 2 years of life, prolonged breast-feeding and upright feeding position should be encouraged, and cigarette smoke exposure should be minimized. Limiting early child care in large groups might also be advisable.

Breast Feeding

Proximate determinants of child mortality in Liberia.

The study looks at the effects of maternal sociodemographic characteristics and the quality of the environment on child survival through two intervening variables, breast-feeding and prenatal care. A linear structural equation modelling approach was used to examine infant and child survival based on a weighted sample of 5180 Liberian children aged 0-5 years. The findings confirm previous studies, but also reveal complex relationships of the role of education, maternal age and breast-feeding in enhancing child survival.

Breast Feeding

Concurrent validity of GHQ-28 and PSE as measures of change.

Substantial cross-sectional correlations have been reported between the GHQ and PSE (and CIS) total scores. Although necessary, this is not a sufficient condition for assuming good validity of the GHQ as a severity measure in longitudinal and health care evaluation studies. For this purpose the GHQ should also accurately reflect changes in severity over time. To examine their concurrent validity, GHQ and PSE scores were compared, in a three-wave longitudinal study, among 175 new psychiatric out-patients. Using a longitudinal structural equation model that takes measurement error into account, the strength of both the cross-sectional and longitudinal relationship between GHQ and PSE were estimated. The GHQ performed remarkably well; changes in severity as defined by PSE-ID and PSE total score were clearly reflected by changes in GHQ scores. The revised scoring method of the GHQ proposed by Goodchild and Duncan-Jones did not yield superior results.

Adult

Relation of media exposure to eating disorder symptomatology: an examination of mediating mechanisms.

Although investigators have postulated that the thin ideal for women espoused in the media is related to the high rates of eating disorders among females, little research has examined the relation between media exposure and eating pathology. This study assessed the relation of media exposure to eating disorder symptoms and tested whether gender-role endorsement, ideal-body stereotype internalization, and body satisfaction mediated this effect. In data from 238 female undergraduates, structural equation modeling revealed a direct effect of media exposure on eating disorder symptoms. Furthermore, mediational linkages were found for gender-role endorsement, ideal body stereotype internalization, and body satisfaction. The results support the assertion that internalization of sociocultural pressures mediate the adverse effects of the thin ideal.

Adult

Alternative representations of war zone stressors: relationships to posttraumatic stress disorder in male and female Vietnam veterans.

Four conceptualizations of war zone stressor experiences were defined: traditional combat, atrocities-abusive violence, perceived threat, and malevolent environment. Items from the National Vietnam Veterans Readjustment Study (NVVRS) were reviewed for content, and stressor indexes were created. Using retrospective self-report data from the NVVRS, intercorrelations among stressor scores and between these scores and measures of posttraumatic stress disorder (PTSD) were computed for all veterans and for men and women separately. Structural equation modeling procedures followed. Results indicated that the four stressor indexes were internally consistent, reasonably distinct from one another, and influenced PTSD differentially. Men scored significantly higher than women on all 4 indexes. Whereas the pattern of relationships among the variables was comparable across genders, there was evidence that one path coefficient in the model differed for men and women.

Combat Disorders

Intimate relationships and depression: is there a causal connection?

The causal pathways that link depression and dissatisfaction in intimate relationships were estimated in 115 patients during the first 12 weeks of treatment with cognitive-behavioral therapy for depression. Depression severity, as measured by the Beck Depression Inventory, was negatively correlated with relationship satisfaction at intake and at 12 weeks. However, structural equation modeling was not consistent with the hypothesis that depression severity has a causal effect on relationship satisfaction levels and suggested that relationship satisfaction may have only a weak reciprocal effect on depression severity. As predicted, married patients were substantially less depressed 12 weeks after the beginning of treatment, when controlling for initial depression severity. Contrary to expectations, marital status predicted improvement even when relationship satisfaction was controlled. Unexpectedly, dysthymia at intake was associated with low relationship satisfaction after 12 weeks, when initial relationship satisfaction was controlled, suggesting that chronic, low-level depression may have a stronger association with interpersonal problems than other forms of depression, such as major depressive episodes. The theoretical and clinical implications of the findings are discussed.

Adolescent

Aging and susceptibility to attitude change.

Two hypotheses about the relation between age and susceptibility to attitude change were tested. The impressionable years hypothesis proposes that individuals are highly susceptible to attitude change during late adolescence and early adulthood and that susceptibility drops precipitously immediately thereafter and remains low throughout the rest of the life cycle. The increasing persistence hypothesis proposes that people become gradually more resistant to change throughout their lives. Structural equation models were applied to data from the 1956-1960, 1972-1976, and 1980 National Election Panel Studies in order to estimate the stability of political attitudes and unreliability in measures of them. The results support the impressionable years hypothesis and disconfirm the increasing persistence hypothesis. A decrease in the over-time consistency of attitude reports among 66- to 83-year-olds was found to be due to increased random measurement error in their reports, not to increased attitude change.

Adolescent

Evidence of differential stability of state and trait anxiety in adults.

This study used Structural Equation Modeling (SEM) to assess the differential longitudinal stabilities of state and trait anxiety. In 1985 and 1987, 227 adult volunteers (ages 22-78) rated themselves on established state and trait questionnaires. In addition, aggregated-state anxiety was measured by self-rated frequency of state anxiety experienced over the previous month. Analysis of split-half subscales from single Trait and State Anxiety scales showed the State Anxiety true score factor to have a significantly lower unstandardized autoregression coefficient (.57 vs. .91), indicating less longitudinal stability. Additional models found longitudinal factor correlations .90, .72, and .66 for Trait, Aggregate-State, and State Anxiety, respectively, further establishing the differential stability of each. There were no significant age differences in longitudinal stability or in within-occasion state-trait factor correlations.

Adult

Intergenerational continuity of parental rejection and depressed affect.

Using survey and observational data from a sample of 451 intact families, this study used structural equation modeling to examine the intergenerational continuity of depressed mood and rejecting parenting. The model partially replicated the intergenerational model of Elder, Caspi, and Downey (1986) that indicates a cyclical transmission process by which parents' personality traits affect parent-child interaction, which, in turn, increases the propensity for developmental problems among offspring. The results indicated a pattern of intergenerational transmission of depressed mood through parental rejection of offspring. Multiple reporters and multiple indicators strengthen previous intergenerational findings by reducing some of the method variance biases that have been problematic in prior studies.

Adolescent

The role of negative affectivity in the association between attributions and marital satisfaction.

Structural equation modeling with latent variables was used to test whether negative affectivity, or the cross-situational tendency to experience and express negative thoughts and feelings, correlates with spouses' attributions for relationship events and accounts for the association between attributions and satisfaction. Eighty married couples completed measures of marital satisfaction, attributions, and negative affectivity. Spouses high in negative affectivity tended to make maladaptive attributions, but spouses' attributions were unrelated to the level of negative affectivity reported by the partner. Attributions and marital satisfaction remained associated among husbands and wives after controlling for negative affectivity. These findings clarify the link between attributions and marital satisfaction and raise the possibility that negative affectivity contributes to the attributions that spouses make for negative events in marriage.

Adaptation, Psychological

Provision and receipt of social support and disregard: what is their impact on the marital life quality of infertile and fertile couples?

A longitudinal study examined perceptions of received and provided social support and disregard among members of 248 infertile and fertile married couples. Correlational and structural equation modeling analyses were conducted. Women's and men's perceptions of the amount of social support they gave to and received from their partner were highly positively related. In contrast, agreement between spouses about the amount of provided support was moderate. Both social support and disregard mediated the relationships between stress and marital quality of life. Overall, highly similar patterns of results were found for members of infertile and fertile couples. These results demonstrate the perceptual element of received support and disregard as well as the importance of considering the provider's perspective.

Adaptation, Psychological

Psychosocial correlates and predictors of AIDS risk behaviors, abortion, and drug use among a community sample, of young adult women.

Relations among latent constructs of Social Conformity, Sensation Seeking, Polydrug Use, Sexual Experience, Abortion, and Risky AIDS Behaviors were examined among a community sample of women (N = 438, mean age = 25.5 years) using confirmatory factor analysis (CFA) and predictive structural equation models (SEM). In the CFA, Risky AIDS Behavior was strongly related to more Polydrug Use and less Social Conformity and modestly related to Sexual Experience and Abortions. In SEMs, Social Conformity significantly predicted less Risky AIDS Behavior and less Polydrug Use but did not predict Abortions. Prior Sexual Experience predicted more Polydrug Use and Abortions. We conclude that the same psychological processes and predispositions that relate low social conformity to drug use and other unhealthy behaviors also influence AIDS-risk behaviors, even among a community sample of women.

Abortion, Induced

A genetic analysis of relative weight among 4,020 twin pairs, with an emphasis on sex effects.

This study replicated previous findings showing a high heritability of obesity, as measured by body mass index (kg/m2), using a measure of relative weight that does not assume a constant regression of height on weight across different populations, and evaluated whether there are sex-limited genetic effects. Subjects were 4,020 adult twin pairs. Alternative causal structural equation models were fitted to variance-covariance matrices. The ADE model (additive genetic effects, dominant/nonadditive genetic effects, and unique environment) fit best. Allowing for sex-specific effects (common sex-limitation model) significantly improved the fit, X2(6) = 230.5, p < .001. The heritability of that portion of weight unrelated to height was large: .61 for men and .73 for women.

Adolescent

The examination of myofascial face pain and its relationship to psychological distress among women.

In this study, 110 female myofascial face pain patients were assessed monthly for 10 months on measures of pain, distress, and stressful life events. D. A. Kenny and A. J. Zautra's (1995) structural equation model for examining the separate trait, state, and error components of the variables was used to analyze the data. Both pain and distress had sizable trait variance, and the trait components were correlated. The 2 variables also showed sizable state variance, and the states of pain covaried with states of distress. A significant time-lagged relationship between the 2 variables was found: Increases in distress led to elevations in pain 1 month later. Stressful life events arising from major social roles were also associated with greater distress, but not pain. Illness events unrelated to the pain syndrome were associated with both pain and distress.

Female

The contribution of personality characteristics to the relationship between social support and perceived physical health.

Although a great deal of research has been conducted on the relationship between social support and physical health, the contribution of personality characteristics to this relationship has rarely been assessed. Structural equation modeling was employed to derive and test a model of the direct and indirect relationships between personality characteristics, social network size, the perceived availability of support, socially supportive behaviors, and perceived physical health with a sample of Pennsylvania adults. Significant paths indicate that individuals who perceive themselves as affiliative and as help seekers and help givers report larger social networks, receive more socially supportive behaviors, and perceive that more support is available to them. The perception that support is available shared a direct relationship with perceived physical health. The utility of including multiple measures of social support and personality characteristics related to receiving support in investigations of the relationship between social support and physical health is discussed.

Adult

A multivariate analysis of adolescents' orientations toward physician use.

Health professionals know surprisingly little about the origins of the health beliefs and orientations they often seek to change, and they do not know about when, or if, changes in these orientations are likely to occur. This study is aimed at increasing our understanding of the origins and development of health beliefs and attitudes by focusing on the impact of parents' orientations toward physician utilization (inclination to consult a doctor when experiencing somatic symptoms) on the comparable orientations of their adolescent children. Hypotheses regarding direct parent-adolescent links are examined within a multivariate structural equations model relating demographics, adolescents' interpersonal competencies, and parental variables to adolescents' orientations toward physician utilization. Evidence for the development of these orientations is obtained by comparing influences across two groups of adolescents: 12- to 13-year-olds and 16- to 18-year-olds. Findings indicate that adolescents' orientations toward physician use are associated with those of their parents and that this link is generally stronger and more specific during late adolescence. The model also suggests that these orientations conform to social and cultural variables related to differences in social stratification.

Adolescent

Health, stress, psychological resources, and subjective well-being among older blacks.

This study examines the structural relationships among sociodemographic characteristics, health status, stress, psychological resources, and subjective well-being (SWB) among the Black elderly. A structural equation model of SWB was evaluated with data from the 1979-1980 National Survey of Black Americans. The results revealed that poor subjective health status was predictive of lower levels of personal efficacy and SWB. Stressful life events tended to depress subjective assessments of health and had negative effects on self-esteem and SWB. Marital status and age had positive effects on SWB. Chronic health conditions and other demographic variables, however, had indirect effects on SWB.

Adaptation, Psychological