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Psychosocial and structural stressors and low engagement in medical care likely contribute to the disproportionate burden of chronic disease among sexual minority men (SMM) across the life course. However, how these stressors impact engagement in medical care among young SMM (YSMM) across racial identities remains understudied. The association of psychosocial and structural stressors with forgoing care among YSMM across racial identities was examined using race-stratified adjusted logistic regression of cross-sectional data. Among 737 HIV-negative SMM aged 16–24 years, nearly all (93%) experienced discrimination in their daily lives. Non-Hispanic/Latinx Black participants reported significantly higher levels of discrimination, exposure to community violence, and food insecurity. Medical mistrust and mental health were not significantly different across racial groups. In the full sample model, education, food insecurity, and discrimination were associated with forgoing care. Among the non-Hispanic/Latinx White sample, medical mistrust and discrimination were associated with forgoing care. Among the non-Hispanic/Latinx Black sample, discrimination was associated with forgoing care. Among the Hispanic/Latinx sample, food insecurity was associated with forgoing care. Psychosocial and structural stressors were common in this YSMM cohort, and significantly different across racial/ethnic identities. Race-stratified analysis revealed differences in the association of stressors with forgoing care among YSMM across racial identities, not appreciated in the analysis limited to the total study population. Our findings may support efforts to address health inequity and improve engagement in medical care among SMM. [ABSTRACT FROM AUTHOR]

High‐intensity interval training (HIIT) has shown significant results in addressing adiposity and risk factors associated with obesity. However, there are no studies that investigate the effects of HIIT on contractility and intracellular Ca2+ handling. The purpose of this study was to explore the impact of HIIT on cardiomyocyte contractile function and intracellular Ca2+ handling in rats in which obesity was induced by a saturated high‐fat diet (HFD). Male Wistar rats were initially randomized into a standard diet and a HFD group. The experimental protocol spanned 23 weeks, comprising the induction and maintenance of obesity (15 weeks) followed by HIIT treatment (8 weeks). Performance was assessed using the maximum oxygen consumption test (V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$). Evaluation encompassed cardiac, adipose and skeletal muscle histology, as well as contractility and intracellular Ca2+ handling. HIIT resulted in a reduction in visceral area, an increase in V̇O2max${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$, and an augmentation of gastrocnemius fibre diameter in obese subjects. Additionally, HIIT led to a decrease in collagen fraction, an increase in percentage shortening, and a reduction in systolic Ca2+/percentage shortening and systolic Ca2+/maximum shortening rates. HIIT induces physiological cardiac remodelling, enhancing the contractile function of cardiomyocytes and improving myofilament sensitivity to Ca2+ in the context of obesity. This approach not only enhances cardiorespiratory and physical performance but also reduces visceral area and prevents interstitial fibrosis. What is the central question of this study?Does high‐intensity interval training (HIIT) enhance myocardial contractility in models of obesity induced by a saturated high‐fat diet, and does it promote an improvement in intracellular Ca2+ handling (Ca2+ influx and reuptake)?What is the main finding and its importance?HIIT, as a non‐pharmacological tool of short duration but high intensity, improves cardiovascular function and the sensitivity of myofilaments to intracellular Ca2+ handling, as well as promoting a reduction in visceral fat area. Thus, the obesity‐induced impairment of the heart's contractile properties was partially prevented by an 8‐week HIIT programme. [ABSTRACT FROM AUTHOR]

Introduction: Cusp ion dispersion signatures reflect properties of remote magnetic reconnection. Since the cusp is easier to observe in situ compared to the reconnection x-line, ion dispersions provide key insight on whether reconnection is variable in space and time. This study is motivated by a specific dispersion signature having two ion populations separated in energy but not space. These are known as overlapping dispersions because when observed by low-Earth orbiting satellites traversing the cusp, they appear as two dispersed ion populations overlapping in magnetic latitudes. Overlapping dispersion signatures have been observed for all interplanetary magnetic field (IMF) orientations and have been associated with multiple reconnection processes, but the three-dimensional magnetic reconnection topology and particle trajectories have not been examined. Methods: Forward particle tracing using the GAMERA-CHIMP global magnetohydrodynamic (MHD) with test particle framework is carried out to construct ion dispersion signatures throughout the cusp. Under idealized solar wind driving with steady purely southward IMF, both standard and overlapping dispersions are found. Results: Analysis of the test particle trajectories shows that the higher energy population of the overlapping dispersion travels along the axis of a flux rope before heading into the cusp, whereas the lower energy population goes directly into the cusp. Furthermore, the overlapping dispersions observed by the synthetic satellites compare well to Defense Meteorological Satellite Program (DMSP) F16 observations during strongly southward IMF. Discussion: It is thus concluded that during strongly southward IMF, cusp-entering particles interacting with a magnetopause flux rope (generated by secondary reconnection) is one way to produce an overlapping dispersion. This study lays the groundwork for the forthcoming NASA Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) mission, which will connect the cusp to the magnetosphere--discovering how spatial or temporal variations in magnetic reconnection drive cusp dynamics. The expected launch of TRACERS is in 2025. [ABSTRACT FROM AUTHOR]

Submarine conduits are features responsible for transporting clastic debris from continents to the deep ocean. While the architecture of conduits has been extensively studied, the process of their inception remains unclear. This study highlights the possibility that some conduits are initiated by depositional processes involving turbidity currents. Here, we present the results of eight experiments where gravity currents were allowed to develop their own pathways. The simulation tank represented natural scales of continental shelves, slopes, and basins. The initial experiments involved sediment-laden flows with low density (1–10% in volume). In first experiment runs (Series I), sediment deposition occurred primarily on the shelf and slope, resulting in an asymmetric transverse profile. This asymmetry facilitated subsequent conservative currents (1034 to 1070 kg/m3 due to salt dissolution) flowing alongside during the second series, resulting in the formation of a constructive submarine conduit. This feature is analogous to gully formations observed in various locations. This study correlates these findings with gully-like features and proposes a model where non-confined density flows can evolve into confined flows through the construction of asymmetric topography. An evolutionary model is proposed to explain the mechanism, which potentially elucidates the formation of many submarine conduits. [ABSTRACT FROM AUTHOR]

The dataset article "Addendum: The Intra-American Traffic of Enslaved People to Rio de Janeiro, 1861-1887: Data from Newspapers Sources" provides detailed information on the traffic of enslaved individuals to Rio de Janeiro from 1861 to 1887. The dataset includes 8,738 new records documenting 88,537 enslaved individuals transported from various ports in Brazil and Spanish Mainland America to Rio de Janeiro. It highlights the impact of the abolitionist campaign in nineteenth-century Brazil, particularly the 1871 Free Womb Law, on the internal slave trade and its eventual decline. The dataset is a valuable resource for researchers studying the history of slavery and the slave trade in the Americas. [Extracted from the article]