Increasing physical activity in postpartum multiethnic women in Hawaii: results from a pilot study

<p>Abstract</p> <p>Background</p> <p>Mothers of an infant are much less likely to exercise regularly compared to other women. This study tested the efficacy of a brief tailored intervention to increase physical activity (PA) in women 3–12 months after childbirth. The study used a pretest-posttest design. Sedentary women (n = 20) were recruited from a parenting organization. Half the participants were ethnic minorities, mean age was 33 ± 3.8, infants' mean age was 6.9 ± 2.4 months, 50% were primiparas, and mean body mass index was 23.6 ± 4.2.</p> <p>Methods</p> <p>The two-month intervention included telephone counseling, pedometers, referral to community PA resources, social support, email advice on PA/pedometer goals, and newsletters.</p> <p>The primary outcome of the study was minutes per week of moderate and vigorous leisure-time physical activity measured by the Godin physical activity instrument.</p> <p>Results</p> <p>All women (100%) returned for post-test measures; thus, paired t-tests were used for pre-post increase in minutes of moderate and vigorous leisure-time physical activity and comparisons of moderate and vigorous leisure-time physical activity increases among ethnic groups. At baseline participants' reported a mean of 3 ± 13.4 minutes per week moderate and vigorous leisure-time physical activity. At post-test this significantly increased to 85.5 ± 76.4 minutes per week of moderate and vigorous leisure-time physical activity (p < .001, Cohen's d = 2.2; effect size r = 0.7). There were no differences in pre to post increases in minutes of moderate and vigorous leisure-time physical activity among races.</p> <p>Conclusion</p> <p>A telephone/email intervention tailored to meet the needs of postpartum women was effective in increasing physical activity levels. However, randomized trials comparing tailored telephone and email interventions to standard care and including long-term follow-up to determine maintenance of physical activity are warranted.</p

Diversity and Evolution of Frog Visual Opsins: Spectral Tuning and Adaptation to Distinct Light Environments

\ua9 The Author(s) 2024. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution. Visual systems adapt to different light environments through several avenues including optical changes to the eye and neurological changes in how light signals are processed and interpreted. Spectral sensitivity can evolve via changes to visual pigments housed in the retinal photoreceptors through gene duplication and loss, differential and coexpression, and sequence evolution. Frogs provide an excellent, yet understudied, system for visual evolution research due to their diversity of ecologies (including biphasic aquatic-terrestrial life cycles) that we hypothesize imposed different selective pressures leading to adaptive evolution of the visual system, notably the opsins that encode the protein component of the visual pigments responsible for the first step in visual perception. Here, we analyze the diversity and evolution of visual opsin genes from 93 new eye transcriptomes plus published data for a combined dataset spanning 122 frog species and 34 families. We find that most species express the four visual opsins previously identified in frogs but show evidence for gene loss in two lineages. Further, we present evidence of positive selection in three opsins and shifts in selective pressures associated with differences in habitat and life history, but not activity pattern. We identify substantial novel variation in the visual opsins and, using microspectrophotometry, find highly variable spectral sensitivities, expanding known ranges for all frog visual pigments. Mutations at spectral-tuning sites only partially account for this variation, suggesting that frogs have used tuning pathways that are unique among vertebrates. These results support the hypothesis of adaptive evolution in photoreceptor physiology across the frog tree of life in response to varying environmental and ecological factors and further our growing understanding of vertebrate visual evolution

Loss of genetic diversity in an outbreeding species: small population effects in the African wild dog (Lycaon pictus)

Genetic studies on the endangered African wild dog (Lycaon pictus) have primarily focused on the few remaining large and viable populations. However, investigations on the many isolated small African wild dog populations might also be informative for species management because the majority of extant populations are small and may contain genetic variability that is important for population persistence and for species conservation. Small populations are at higher risk of extinction from stochastic and deterministic demographic processes than larger populations and this is often of more immediate conservation concern than loss of genetic diversity, particularly for species that exhibit out-breeding behaviour such as long distance dispersal which may maintain gene flow. However, the genetic advantages of out-breeding behaviour may be reduced if dispersal is compromised beyond reserve borders (edge effects), further weakening the integrity of small populations. Mitochondrial DNA and 11 microsatellite genetic markers were used to investigate population genetic structure in a small population of out-breeding African wild dogs in Zambia, which occupies an historical dispersal corridor for the species. Results indicated the Zambian population suffered from low allelic richness, and there was significant evidence of a recent population bottleneck. Concurrent ecological data suggests these results were due to habitat fragmentation and restricted dispersal which compromised natural out-breeding mechanisms. This study recommends conservation priorities and management units for the African wild dog that focus on conserving remaining levels of genetic diversity, which may also be applicable for a range of out-breeding species