Achilles tendon material properties are greater in the jump leg of jumping athletes

Purpose: The Achilles tendon (AT) must adapt to meet changes in demands. This study explored AT adaptation by comparing properties within the jump and non-jump legs of jumping athletes. Non-jumping control athletes were included to control limb dominance effects. Methods: AT properties were assessed in the preferred (jump) and non-preferred (lead) jumping legs of male collegiate-level long and/or high jump (jumpers; n=10) and cross-country (controls; n=10) athletes. Cross-sectional area (CSA), elongation, and force during isometric contractions were used to estimate the morphological, mechanical and material properties of the ATs bilaterally. Results: Jumpers exposed their ATs to more force and stress than controls (all p≤0.03). AT force and stress were also greater in the jump leg of both jumpers and controls than in the lead leg (all p0.05). Conclusion: ATs chronically exposed to elevated mechanical loading were found to exhibit greater mechanical (stiffness) and material (Young’s modulus) properties

The social and sexual lives of Black sexual minority men 30 years of age and older in South Africa

ADDITIONAL FILE 1. Quantitative survey.BACKGROUND : Black sexual minority men (SMM) ages 30 and older are under-represented in HIV studies in sub- Saharan Africa, despite being at increased risk of HIV infection and contributing to potential onward HIV transmission. To better understand the social and sexual lives of older Black South African SMM, we conducted in-depth interviews with SMM who were > 30 years old. METHODS : From March–September 2016, we recruited a convenience sample of 37 SMM ages 30 and older by partnering with an LGBTQ+ organization in Tshwane, Pretoria. Men were interviewed about various aspects of their lives, including their sexual orientation, social connectedness, experiences with stigma and perspectives on participating in research. RESULTS : Participants described their experiences with their sexual identities, cultural and social implications of disclosure, and their perspective on South Africa’s political perspectives on the LGBTQ+ community. Men described how these experiences influence their trust in research and comfort participating in studies. CONCLUSIONS : Inferences drawn from these findings provide direction on how to improve middle-aged SMM’s representation in research, such as recruiting a higher proportion of older and middle-aged SMM to serve as seed participants and building stronger community partnerships to disseminate study findings to settings where data collection is conducted.The Fulbright U.S. Student Program, NIMH and NIAAA.http://www.biomedcentral.com/bmcpublichealtham2023PsychologySociolog

UNBOUND

UNBOUND showcases the graduating class from the fashion design school at Fanshawe College.https://first.fanshawec.ca/famd_design_fashiondesign_unbound/1007/thumbnail.jp

Multiple Origins of Knockdown Resistance Mutations in the Afrotropical Mosquito Vector Anopheles gambiae

How often insecticide resistance mutations arise in natural insect populations is a fundamental question for understanding the evolution of resistance and also for modeling its spread. Moreover, the development of resistance is regarded as a favored model to study the molecular evolution of adaptive traits. In the malaria vector Anopheles gambiae two point mutations (L1014F and L1014S) in the voltage-gated sodium channel gene, that confer knockdown resistance (kdr) to DDT and pyrethroid insecticides, have been described. In order to determine whether resistance alleles result from single or multiple mutation events, genotyping of the kdr locus and partial sequencing of the upstream intron-1 was performed on a total of 288 A. gambiae S-form collected from 28 localities in 15 countries. Knockdown resistance alleles were found to be widespread in West Africa with co-occurrence of both 1014S and 1014F in West-Central localities. Differences in intron-1 haplotype composition suggest that kdr alleles may have arisen from at least four independent mutation events. Neutrality tests provided evidence for a selective sweep acting on this genomic region, particularly in West Africa. The frequency and distribution of these kdr haplotypes varied geographically, being influenced by an interplay between different mutational occurrences, gene flow and local selection. This has important practical implications for the management and sustainability of malaria vector control programs

Deciding to Dissolve: Individual- and Relationship-Level Predictors of Roommate Breakup

The desire to change roommates served as a model of nonromantic relationship dissolution within 115 college roommate dyads. We measured personality, mental health, social/communication patterns, and academic achievement attitudes over the course of a semester, and we used multilevel modeling to estimate individual-level and relationship-level predictors of dissolution. Self-characteristics (e.g., one’s own depression), roommate characteristics (e.g., roommate’s poor communication) and relationship characteristics (e.g., similarity in attitudes toward competition) each increased desire to end the roommate relationship. In these data, unique contributions from one’s own psychological health, one’s own and one’s roommate’s social/communication style, and roommates’ attitude similarity predicted relationship dissolution