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A study assesses primary (after hatching) and secondary (after juvenile mortality) outcrossing rates of two mixed-mating snail populations in order to investigate the variation in mating-system parameters and estimate significance of inbreeding depression for secondary outcrossing rate. Results show that outcrossing rate is much more variable among families in the population with the lower average outcrossing rate, suggesting that individuals differ considerably in the mating system.

The influence of parental effort on susceptibility to parasitism wasinvestigated experimentally in the Eurasian kestrel (Falco tinnunculus) in Finland. Parental effort was manipulated by either enlarging or reducing broods by 1-2 young, while unmanipulated broods served as controls. This was done during 3 breeding seasons, during which the densities of the major prey of kestrels (voles) were relatively low, high and intermediate, respectively. Two, taxon specific, methods wereapplied for determining the prevalence (per cent individuals infected) of extracellular Trypanosoma spp. and intracellular Haemoproteus spp. infection. Blood samples were taken from females during the incubation phase, and from both parents during the mid-nestling phase. Trypanosoma was more prevalent when food was less available. Furthermore, the increase in the prevalence of Trypanosoma among females was most pronounced during the poor vole year. In contrast, Haemoproteus infection seemed not closely related to annual supply of main prey. Manipulations of parental effort were related to parental infection, but the effect differed between genders. The prevalence of Trypanosoma inmales (main provider of young) increased with experimental brood size, and there was an interaction between food supply and brood size manipulation so that the difference in prevalences between reduced and enlarged broods increased with decreasing food supply. Among females,no such an interaction was found. Instead, the effect of brood enlargement on Trypanosoma prevalence of females was apparent in the year of relatively high vole densities only. Manipulation of brood size did not have clear effects on Haemoproteus infection in either gender. These results support the idea that increased parental effort may make hosts susceptible to haematozoan infection, and are the first to suggest that resource levels (food supply) can modify the susceptibility, indicating that the magnitude of reproductive costs can be attributed [ABSTRACT FROM AUTHOR]

Objectives: Depression is a major contributor of young people's burden of disease. In this study we aim to estimate the effect of elevated depressive symptoms on physical health-related quality of life., Design: We used self-reported information from the prospective BELLA cohort study, which included adolescents selected from the general population in Germany. The baseline assessment (2003-2006) and the 1-, 2-, and 6-year follow-up waves provide the data basis., Participants: The baseline study population consisted of 1,460 adolescents between the ages of 12 and 17 who, according to their caregivers, did not suffer from depression., Variables: The primary outcome, as measured by the physical component score (PCS) of the SF-36 at a 6-year follow-up (range: 0-100), is physical health-related quality of life. The exposure of interest is depressive symptoms, as measured by the Center for Epidemiological Studies Depression Scale for Children (CES-DC) at baseline, 1-year follow-up and 2-year follow-ups (range: 0-60). We dichotomized the exposure into subthreshold (≤15) and elevated depressive symptoms (>15). For the main analyses we considered a cumulative index for elevated depressive symptoms across the three time points (range: 0-3). Considered confounders are sex, age, socioeconomic status, migrant background, social support, anxiety symptoms, physical activity, chronic diseases, and sleeping problems., Statistical Methods: We used multiple imputation to account for missing values. Within each imputed dataset, we applied inverse probability weighting (IPW) to estimate the effect of the cumulative index for elevated depressive symptoms at baseline, 1- and 2-year follow-up on physical health-related quality of life at 6-year follow-up. We derived 95% confidence intervals by bootstrapping., Results: After adjusting with IPW, the effect of the cumulative index per one unit increase of elevated depressive symptoms on the physical component score was -1.71 (95% CI: -3.51 to -0.04). The adjusted effect estimates of single exposure of elevated depressive symptoms on physical health-related quality of life were -0.83 (95% CI: -3.69 to 1.87) at baseline, -2.96 (95% CI: -4.94 to -0.52) at 1-year follow-up and -1.32 (95% CI: -3.85 to 1.15) at 2-year follow-up., Conclusion: Findings suggest that elevated depressive symptoms during adolescence decrease physical health-related quality of life in young adulthood., Competing Interests: MP reports having received partial funding for a self-initiated research project from Novartis Pharma. MP further reports being awarded a research grant from the Center for Stroke Research Berlin (private donations) for a self-initiated project. TK reports, outside of the submitted work, having received research grants from Gemeinsamer Bundesausschuss (G-BA - Federal Joint Committee, Germany), the Bundesministerium für Gesundheit (BMG - Federal Ministry of Health, Germany). He further has received personal compensation from Eli Lilly and Company, The BMJ, and Frontiers Media S.A. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2024 Wiehn, Kurth, Ravens-Sieberer, Prugger, Piccininni and Reiss.)

Objectives: This study aimed to investigate adherence to Consolidated Standards of Reporting Trials (CONSORT) for abstracts in reports of randomised trials on child and adolescent depression prevention. Secondary objective was to examine factors associated with overall reporting quality., Design: Meta-epidemiological study., Data Sources: We searched MEDLINE, EMBASE, PsycINFO, PsycArticles and CENTRAL., Eligibility Criteria: Trials were eligible if the sample consisted of children and adolescents under 18 years with or without an increased risk for depression or subthreshold depression. We included reports published from 1 January 2003 to 8 August 2020 on randomised controlled trials (RCTs) and cluster randomised trials (CRTs) assessing universal, selective and indicated interventions aiming to prevent the onset of depression or reducing depressive symptoms., Data Extraction and Synthesis: As the primary outcome measure, we assessed for each trial abstract whether information recommended by CONSORT was adequately reported, inadequately reported or not reported. Moreover, we calculated a summative score of overall reporting quality and analysed associations with trial and journal characteristics., Results: We identified 169 eligible studies, 103 (61%) RCTs and 66 (39%) CRTs. Adequate reporting varied considerably across CONSORT items: while 9 out of 10 abstracts adequately reported the study objective, no abstract adequately provided information on blinding. Important adverse events or side effects were only adequately reported in one out of 169 abstracts. Summative scores for the abstracts' overall reporting quality ranged from 17% to 83%, with a median of 40%. Scores were associated with the number of authors, abstract word count, journal impact factor, year of publication and abstract structure., Conclusions: Reporting quality for abstracts of trials on child and adolescent depression prevention is suboptimal. To help health professionals make informed judgements, efforts for improving adherence to reporting guidelines for abstracts are needed., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: A mental health crisis has hit university campuses across the world. This study sought to determine the prevalence and social determinants of depressive symptoms among university students in twelve countries. Particular focus was placed on the association between social capital and depressive symptoms., Methods: A cross-sectional study was conducted among students at their first year at university in Europe, Asia, the Western Pacific, and Latin and North America. Data were obtained through a self-administered questionnaire, including questions on sociodemographic characteristics, depressive symptoms, and social capital. The simplified Beck's Depression Inventory was used to measure the severity of depressive symptoms. Social capital was assessed using items drawn from the World Bank Integrated Questionnaire to Measure Social Capital. Multilevel analyses were conducted to determine the relationship between social capital and depressive symptoms, adjusting for individual covariates (e.g., perceived stress) and country-level characteristics (e.g., economic development)., Results: Among 4228 students, 48% presented clinically relevant depressive symptoms. Lower levels of cognitive (OR: 1.82, 95% CI: 1.44-2.29) and behavioral social capital (OR: 1.51, 95% CI: 1.29-1.76) were significantly associated with depressive symptoms. The likelihood of having depressive symptoms was also significantly higher among those living in regions with lower levels of social capital., Conclusion: The study demonstrates that lower levels of individual and macro-level social capital contribute to clinically relevant depressive symptoms among university students. Increasing social capital may mitigate depressive symptoms in college students., (Copyright © 2020 Backhaus, Varela, Khoo, Siefken, Crozier, Begotaraj, Fischer, Wiehn, Lanning, Lin, Jang, Monteiro, Al-Shamli, La Torre and Kawachi.)

Background: Adverse childhood experiences (ACEs) have been shown to be linked to health risk behaviours (HRBs). This study aims to identify risk factors for ACEs and to examine the associations between ACEs and single and multiple HRBs in a sample of university students in Germany., Methods: An online-based cross-sectional study was conducted among public university students (N = 1466). The widely applied ACE questionnaire was used and extended to operationalise 13 categories of childhood adversity. First, variables for each type of ACE and HRB were dichotomised (single ACEs and single HRBs), and then used for cumulative scores (multiple ACEs and multiple HRBs). Frequencies were assessed, and (multinomial) logistic regression analyses were performed., Results: Prevalence rates of ACEs ranged from 3.9 to 34.0%, depending on the type of childhood adversity. Sociodemographic risk and protective factors for single/multiple ACEs varied strongly depending on the outcome. In particular, a high family socioeconomic status seemed to be a consistent protective factor for most ACEs. After adjusting for sociodemographic characteristics, both single and multiple HRBs were associated with single events of ACEs. Moreover, dose-response relationships between multiple ACEs and various single and multiple HRBs were found., Conclusions: The study provides strong evidence that ACEs are associated with HRBs. The number of ACEs may play a role in single or multiple HRBs. Reducing the number of ACEs could thus decrease HRBs, which account for many of the leading causes of morbidity and death. The findings highlight the importance of trauma-informed health interventions designed to prevent the occurrence of ACEs, and build capacity among children and adults.

Genetic compatibility, nonspecific defenses, and environmental effects determine parasite resistance. Host mating system (selfing vs. outcrossing) should be important for parasite resistance because it determines the segregation of alleles at the resistance loci and because inbreeding depression may hamper immune defenses. Individuals of a mixed mating hermaphroditic freshwater snail, Lymnaea ovata, are commonly infected by a digenetic trematode parasite, Echinoparyphium recurvatum. We examined covariation between quantitative resistance to novel parasites and mating system by exposing snail families from four populations that differed by their inbreeding coefficients. We found that resistance was unrelated to inbreeding coefficient of the population, suggesting that the more inbred populations did not carry higher susceptibility load than the less inbred populations. Most of the variation in resistance was expressed among the families within the populations. In the population with the lowest inbreeding coefficient, resistance increased with outcrossing rate of the family, as predicted if selfing had led to inbreeding depression. In the other three populations with higher inbreeding coefficients, resistance was unrelated to outcrossing rate. The results suggest that in populations with higher inbreeding some of the genetic load has been purged, uncoupling the predicted relationship between outcrossing rate and resistance. Snail families also displayed crossing reaction norms for resistance when tested in two environments that presented low and high immune challenge, suggesting that genotype-by-environment interactions are important for parasite resistance.

The propagation and scattering of ultrasound in concrete is discussed. The heterogeneous composition of concrete causes the ultrasound to scatter considerably. In the limit of many scattering events, the ultrasonic energy density in circular cylinders of concrete is shown to evolve in accordance with a one-dimensional diffusion equation. The ultrasonic diffusivity and dissipation are measured experimentally over the frequency range of 100-900 kHz. Theoretical descriptions of the diffusivity are in accord with the experimental values. Such frequencies are well above typical frequencies used for concrete inspection. Thus, it is anticipated that the use of these higher frequencies will result in new techniques for characterizing material properties and damage in concrete structures.

Reversed sexual size dimorphism (RSD, females larger than males) is commonly found in birds of prey. We used kestrels (Falco tinnunculus), breeding in western Finland in a temporally varying environment of 3-year vole cycles, to assess current hypotheses for the evolution and maintenance of RSD. Our 12-year data showed only weak correlations between parental size and breeding parameters (laying date, clutch size and the number of fledglings produced). The degree of RSD per se was unrelated to breeding success, contrary to the prediction of the female dominance hypothesis. Females with small males produced larger clutches in low-vole years, independently of laying date, which supports the small male (or its equivalent inter-sexual selection) hypothesis. Small females tended to have more fledglings, particularly in low-vole years, which is inconsistent with the hypotheses for an advantage of large female size (the starvation, intra-sexual selection, reproductive effort, and supplementary feeding hypotheses). As for males, smaller females may be more efficient hunters, the importance of which should be most pronounced under harsh breeding conditions. Our results suggest that the directional selection on a particular size in kestrels may be under contrasting selection pressures by the environment, and, at least in breeding females, the advantages of large size can actually be counterbalanced during harsh environmental conditions.

Many hypotheses for hatching asynchrony within avian clutches centre around food supply during the laying or nestling periods, but food is measured in few studies. Patterns of clutch size and hatching asynchrony were analysed in the Eurasian kestrel [Falco tinnunculus (Linnaeus)] breeding in Finland, where small mammal populations show dramatic 3-year cycles. Data collected over 12 years showed that clutches were larger when food was more abundant in spring. While controlling for clutch size, hatching was more synchronous in the low phase of the vole cycle compared to the increase phase, contrary to conventional interpretation of the brood reduction hypothesis. The age of the female, but not the age of the male was associated with the degree of asynchrony. Paradoxically, numbers of voles were most stable in the 'low' phase, which may lead to a unique situation, where food is more predictable when scarce. Kestrels have small, synchronous clutches in the 'low' phase and large asynchronous clutches in the 'increase' phase. Based on results of this study, it is suggested that it is important to consider the predictability of food, and not only the mean abundance of food when evaluating hypotheses for hatching asynchrony. Patterns of clutch size and hatching asynchrony at the population level can be used to evaluate current energy-related hypotheses for asynchrony.

We investigated intraspecific variation in incubation behaviour of wild Eurasian kestrels, Falco tinnunculus, in Finland and tested whether patterns of hatching asynchrony could be predicted from patterns of incubation. The timing of the onset of incubation varied considerably for 17 female kestrels. Eggs generally hatched in the order they were laid, and both total hatching span of the clutch and the pattern of eggs hatching on certain days corresponded well with incubation behaviour. This result was consistent with the idea that females have much control over hatching patterns. In the majority (65%) of cases, the proportion of daily incubation increased monotonically with the laying sequence, a pattern described previously in other birds. Unusual patterns of incubation (35%) were most common in females with poor body condition during incubation and may be the result of energy constraints during laying.Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.