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This study used Control-Value Theory to examine the extent to which appraisals of control and value predicted students' intentions to complete their studies and whether the effects of these appraisals on completion intentions are mediated by the achievement emotions of enjoyment, frustration, anger and boredom. A sample of 158 Australian vocational education students completed a survey measuring control, value, achievement emotions and intentions to complete. Structural Equation Modelling revealed that both higher levels of control and higher levels of value predicted intentions to complete, though no support was found for an interaction between control and value in predicting completion intentions. Contrary to expectations, no support was found for achievement emotions mediating the relationships between both control and value and intentions to complete. It was concluded that subjective control and value may act as protective resources for students in maintaining their intentions to complete their studies.

Background: Measurement of rat anogenital distance (AGD) dates to at least 1912. Increased interest in endocrine disrupting chemicals and the use of AGD as a biomarker for fetal androgen effects have increased the number of studies with this endpoint in recent decades. A literature review revealed different landmarks, methods of measurement, and methods to adjust for body weight differences. AGD is often reported to hundredths of millimeters and as such, deserves precision in all these aspects. This paper presents recommendations for the measurement and analysis of rodent AGD. Methods: Literature and regulatory guidance documents that mentioned or measured rodent AGD were reviewed. Four adjustment methods were evaluated using available online data from three rat studies each with two generations of offspring. Results: Tabulation of studies reveals that species/stocks and time of data collection, but more importantly anatomical landmarks and methods of measurement have produced a variety of results which are difficult to compare. Not all studies have adjusted for test article effects on body weight (and thus size). The four adjustment methods were fairly comparable. Conclusion: Recommendations are as follows. A microscopic method should be used to measure AGD of late rodent fetuses and early postnatal pups. The caudal edge of the genital tubercle and the cranial edge of the anus are clear and identifiable landmarks. The simplest adjustment is to divide individual AGDs by the cube root of animals' body weight. These recommendations will help ensure data consistency and accuracy, and facilitate meaningful comparisons across laboratories and chemical classes. [ABSTRACT FROM AUTHOR]

STUDY QUESTION To what extent do self-reported sleep duration and non-daytime work schedules in either partner affect the rate of spontaneous abortion (SAB)? SUMMARY ANSWER Incidence of SAB had little association with female sleep duration and a modest positive association with male short sleep duration, female work at night, and discrepant work schedules among partners. WHAT IS KNOWN ALREADY Several studies have reported an association between short sleep duration in either partner and reproductive health outcomes, including fecundability. Moreover, certain types of female occupational exposures during pregnancy have been associated with an increased risk of SAB. No studies have evaluated SAB risk in relation to male sleep and work schedules, or joint exposures within a couple. STUDY DESIGN, SIZE, DURATION This prospective cohort study included 9357 female participants and 2602 of their male partners residing in North America (June 2013 to April 2023). PARTICIPANTS/MATERIALS, SETTING, METHODS Participants enrolled when they were attempting pregnancy and completed self-administered baseline questionnaires about their average sleep duration and work schedules. Among those who conceived, we ascertained SAB and gestational age at loss via follow-up questionnaires. We used multivariable Cox proportional hazards models with gestational weeks as the time scale to estimate hazard ratios (HRs) and 95% CIs relating SAB with sleep duration and non-daytime work schedules for female and male participants, and the couple. We used inverse probability weighting to account for potential selection bias due to the possibility of differential participation of male partners with respect to the exposures. MAIN RESULTS AND THE ROLE OF CHANCE Compared to female participants with recommended sleep (7–8.9 h), those reporting short sleep duration (<6 h) did not have a higher rate of SAB (HR 0.88, 95% CI 0.69, 1.13). Short self-reported sleep duration among male participants was modestly associated with a higher rate of SAB (adjusted and weighted HR 1.30, 95% CI 0.96, 1.75). Female night work at night (adjusted HR 1.19, 95% CI 1.02, 1.38) and male non-daytime work (adjusted and weighted HR 1.26, 95% CI 1.00, 1.59) were associated with modestly higher rates of SAB, whereas female rotating shift work was not (adjusted HR 0.91, 0.78, 1.05) compared with daytime workers. Couples in which work schedules were discrepant had an elevated rate of SAB if the male partner worked a non-daytime shift (adjusted and weighted HR 1.46, 95% CI 1.13, 1.88) compared with couples in which both members worked during the day. The corresponding HR if only the female partner worked a non-daytime shift was 1.21 (95% CI 0.92, 1.58). LIMITATIONS, REASONS FOR CAUTION Data on sleep duration and work schedules were based on self-report, which is vulnerable to misclassification, particularly since participants were asked to report their average sleep duration during the past month. Work exposures were heterogeneous, as many different types of employment may require night and shift work and may have different associations with SAB. WIDER IMPLICATIONS OF THE FINDINGS Our findings are consistent with previous research indicating that some types of female employment schedules may be associated with SAB incidence. This is the first study to indicate a relationship between SAB and male employment schedules, indicating that discrepant work schedules within a couple might be relevant. STUDY FUNDING/COMPETING INTEREST(S) This work was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development grants R01HD105863 (PIs: L.A.W. and M.L.E.), R01HD086742 (PIs: L.A.W. and E.E.H.), and R21HD072326 (PI: L.A.W.). PRESTO has received in-kind donations from Swiss Precision Diagnostics and Kindara.com for primary data collection. L.A.W. is a consultant for AbbVie, Inc. and the Gates Foundation. M.L.E. is an advisor for and holds stock in Ro, Hannah, Dadi, Underdog, Vseat, & Doveras. The other authors have no competing interests to declare. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Background: A new derived (i.e., calculated) endpoint of developmental toxicology has appeared in a very few studies since 1990. This endpoint is adjusted mean live fetal weight per litter or adjusted fetal weight. Given our lack of familiarity with the endpoint, we evaluated the basis, prevalence, methods, and usefulness in embryo‐fetal developmental toxicity (EFDT) studies in rats. Methods: Literature searches were performed with key terms using PubMed and Google Scholar. Major textbooks were consulted but lack of any mention of the endpoint. Unpublished EFDT data, which are readily available online, were utilized to test adjustment methods. Results: Pertinent information on factors that influence fetal weight goes back a century. Four papers utilizing rats were found in which fetal weights were adjusted using either statistical or formula‐based methods to adjust fetal weights. Only one study showed a clear benefit to the endpoint when there was a marked decrease in live litter size; this pointed to situations in which the new endpoint might be useful. The lone formula‐based adjustment method was found to be lacking adequate testing and justifications. A new experimental alternative formula‐based adjustment is shown to produce results very similar to statistical methods. Conclusions: From this assessment, we recommend that adjusted fetal weight should not be a routine endpoint at this time. However, there are likely cases where this derived endpoint could aid interpretation. We encourage other investigators to examine previous EFDT study data to establish guidance on the use of adjusted mean live fetal weights. [ABSTRACT FROM AUTHOR]