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Obesity and other inactivity related diseases are increasing at an alarming rate especially in Western societies. Because of this, it is important to understand the regulating mechanisms involved in physical activity behavior. Much research has been done in regard to the psychological determinants of physical activity behavior; however, little is known about the underlying genetic and biological factors that may contribute to regulation of this complex trait. It is true that a significant portion of any trait is regulated by genetic and biological factors. In the case of voluntary physical activity behavior, these regulating mechanisms appear to be concentrated in the central nervous system. In particular, the dopamine system has been shown to regulate motor movement, as well as motivation and reward behavior. The pattern of regulation of voluntary physical activity by the dopamine system is yet to be fully elucidated. This review will summarize what is known about the dopamine system and regulation of physical activity, and will present a hypothesis of how this signaling pathway is mechanistically involved in regulating voluntary physical activity behavior. Future research in this area will aid in developing personalized strategies to prevent inactivity related diseases.

OBJECTIVES: We compared recent parents (married, cohabiting, not cohabiting but romantically involved, and not romantically involved) to examine the association between mental health problems and relationship status. METHODS: We analyzed data from the Fragile Families and Child Wellbeing Study that followed a cohort of approximately 4900 births in large US cities. Our study included a large oversample of nonmarital births (n=3700) and interviews with both mothers and fathers. We used the Composite International Diagnostic Interview Short Form to assess depression and generalized anxiety 1 year after the birth. Self reports were used to measure heavy drinking, illicit drug use, incarceration, and partner violence. RESULTS: Unmarried parents reported more mental health and behavioral problems than did married parents, and unmarried parents whose relationships ended before the birth reported more impairment compared with other groups of unmarried parents. CONCLUSIONS: A substantial number of children are born to unmarried parents and are at risk for poor parenting and poor developmental outcomes. Government initiatives aimed at increasing marriage rates among low-income couples need to consider the mental health status of unmarried parents. [ABSTRACT FROM AUTHOR]

We use terahertz time domain spectroscopy to examine finite size effects on the optical phonon modes in SrTiO3 thin films. In temperature-dependent measurements we find a near absence of mode softening in the TO1 phonon frequency. Furthermore we see an increase in the soft mode frequency with reduced thickness. Both of these results correlate well with the reduced dielectric response observed for nanoscale ferroelectric systems. [Copyright &y& Elsevier]

Rapid, unidirectional pollen tube tip growth is essential for fertilization and widely employed as a model of polar cell expansion, a process crucial for plant morphogenesis. Different proteins and lipids with key functions in the control of polar cell expansion are associated with distinct domains of the plasma membrane (PM) at the pollen tube tip. These domains need to be dynamically maintained during tip growth, which depends on massive secretory and endocytic membrane trafficking. Very little is currently known about the molecular and cellular mechanisms responsible for the compartmentalization of the pollen tube PM. To provide a reliable structural framework for the further characterization of these mechanisms, an integrated quantitative map was compiled of the relative positions in normally growing Nicotiana tabacum (tobacco) pollen tubes of PM domains (i) enriched in key signaling proteins or lipids, (ii) displaying high membrane order, or (iii) in contact with cytoplasmic structures playing important roles in apical membrane trafficking. Previously identified secretory and endocytic PM domains were also included in this map. Internalization of regulatory proteins or lipids associated with PM regions overlapping with the lateral endocytic domain was assessed based on brefeldin A treatment. These analyses revealed remarkable aspects of the structural organization of tobacco pollen tube tips, which (i) enhance our understanding of cellular and regulatory processes underlying tip growth and (ii) highlight important areas of future research., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Purpose: This review examined whether there is evidence that brief interventions with condom demonstration lessons have impacts on behavioral and nonbehavioral outcomes for youth and young adults., Methods: We conducted a systematic review using a prespecified search strategy and processes consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We identified a pool of 11 eligible studies that tested the effectiveness of a single-session intervention that was no longer than 60 minutes and included a condom demonstration. We included all outcomes at all time points and organized them into eight domains., Results: Single-session interventions with condom demonstrations showed favorable short-term and long-term impacts for samples of largely sexually active youth. Studies found statistically significant impacts in 29%-50% of the tests for effects on attitudes toward condoms, knowledge of sexual health and condom use, perceptions of condom use and sexuality, and condoms use intentions., Discussion: Our review found evidence that brief interventions with condom demonstrations have potential effects on behavioral and nonbehavioral outcomes for vulnerable and transient sexually active youth warranting future studies to assess condom demonstrations in isolation., (Copyright © 2023 Society for Adolescent Health and Medicine. All rights reserved.)

Pollen tubes of higher plants grow very rapidly until they reach the ovules to fertilize the female gametes. This growth process is energy demanding, however, the nutrition strategies of pollen are largely unexplored. Here, we studied the function of sucrose transporters and invertases during pollen germination and pollen tube growth. RT-PCR analyses, reporter lines and knockout mutants were used to study gene expression and protein function in pollen. The genome of Arabidopsis thaliana contains eight genes that encode functional sucrose/H + symporters. Apart from AtSUC2 , which is companion cell specific, all other AtSUC genes are expressed in pollen tubes. AtSUC1 is present in developing pollen and seems to be the most important sucrose transporter during the fertilization process. Pollen of an Atsuc1 knockout plant contain less sucrose and have defects in pollen germination and pollen tube growth. The loss of other sucrose carriers affects neither pollen germination nor pollen tube growth. A multiple knockout line Atsuc1Atsuc3Atsuc8Atsuc9 shows a phenotype that is comparable to the Atsuc1 mutant line. Loss of AtSUC1 can`t be complemented by AtSUC9, suggesting a special function of AtSUC1. Besides sucrose carriers, pollen tubes also synthesize monosaccharide carriers of the AtSTP family as well as invertases. We could show that AtcwINV2 and AtcwINV4 are expressed in pollen, AtcwINV1 in the transmitting tissue and AtcwINV5 in the funiculi of the ovary. The vacuolar invertase AtVI2 is also expressed in pollen, and a knockout of AtVI2 leads to a severe reduction in pollen germination. Our data indicate that AtSUC1 mediated sucrose accumulation during late stages of pollen development and cleavage of vacuolar sucrose into monosaccharides is important for the process of pollen germination., Competing Interests: The 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., (Copyright © 2023 Seitz, Reimann, Fritz, Schröder, Knab, Weber and Stadler.)

Purpose: This case study discusses Mathematica's experience providing large-scale evaluation technical assistance (ETA) to 65 grantees across two cohorts of Teen Pregnancy Prevention (TPP) Program grants. The grantees were required to conduct rigorous evaluations with specific evaluation benchmarks. This case study provides an overview of the TPP grant program, the evaluation requirements, the ETA provider, and other key stakeholders and the ETA provided to the grantees. Finally, it discusses the successes, challenges, and lessons learned from the effort., Conclusion: One important lesson learned is that there are two related evaluation features, strong counterfactuals and insufficient target sample sizes, that funders should attend to prior to selecting awardees because they are not easy to change through ETA. In addition, if focused on particular outcomes (for TPP, the goal was to improve sexual behavior outcomes), the funder should prioritize studies with an opportunity to observe differences in these outcomes across conditions; several TPP grantees served young populations, and sexual behavior outcomes were not observed or were rare, limiting the opportunity to observe impacts. Unless funders are attentive to weaning out evaluations with critical limitations during the funding process, requiring grantees to conduct impact evaluations supported by ETA might unintentionally foster internally valid, yet underpowered studies that show nonsignificant program impacts. The TPP funder was able to overcome some of the limitations of the grantee evaluations by funding additional evidence-building activities, including federally led evaluations and a large meta-analysis of the effort, as part of a broader learning agenda.