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1.
Community Health Equity Res Policy ; : 2752535X241260444, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38848753

ABSTRACT

BACKGROUND: Ample evidence demonstrates Latina adolescents' elevated risk for sexual health disparities, but knowledge of how they manage their sexual health during this critical period of sexual development is limited. Countering the overfocus on Latina adolescents as "at-risk" girls in extant research, this study uses a strengths-based perspective to explore this topic. METHODS: This study used a narrative research design to gather and analyze the stories of 18 Latina young people who attended school in New York. We employed holistic-content and categorical-content approaches to identify themes and interpret findings through a strengths-based view of sexual health. RESULTS: We identified three major themes across participants' narratives: (1) agency in gaining sexual health information; (2) self-protection; and (3) obtaining sexual healthcare despite barriers. CONCLUSIONS: Findings underscore the need for more inclusive, culturally relevant sexual health education initiatives, youth-centered services, and interventions that capitalize on the strengths of Latina adolescents.

2.
Nature ; 628(8009): 723-724, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38632416
3.
J Hered ; 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38366852

ABSTRACT

Endosperm in angiosperms and placenta in eutherians are convergent innovations for efficient embryonic nutrient transfer. Despite advantages, this reproductive strategy incurs metabolic costs that maternal parents disproportionately shoulder, leading to potential inter-parental conflict over optimal offspring investment. Genomic imprinting-parent-of-origin-biased gene expression-is fundamental for endosperm and placenta development and has convergently evolved in angiosperms and mammals, in part, to resolve parental conflict. Here, we review the mechanisms of genomic imprinting in these taxa. Despite differences in the timing and spatial extent of imprinting, these taxa exhibit remarkable convergence in the molecular machinery and genes governing imprinting. We then assess the role of parental conflict in shaping evolution within angiosperms and eutherians using four criteria: (1) Do differences in the extent of sibling relatedness cause differences in the inferred strength of parental conflict? (2) Do reciprocal crosses between taxa with different inferred histories of parental conflict exhibit parent-of-origin growth effects? (3) Are these parent-of-origin growth effects caused by dosage-sensitive mechanisms and do these loci exhibit signals of positive selection? (4) Can normal development be restored by genomic perturbations that restore stoichiometric balance in the endosperm/placenta? Although we find evidence for all criteria in angiosperms and eutherians, suggesting that parental conflict may help shape their evolution, many questions remain. Additionally, myriad differences between the two taxa suggest that their respective biologies may shape how/when/where/to what extent parental conflict manifests. Lastly, we discuss outstanding questions, highlighting the power of comparative work in quantifying the role of parental conflict in evolution.

4.
Inorg Chem ; 63(1): 84-91, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-37651259

ABSTRACT

Aqueous solutions of zirconium and hafnium (M) halides (X) with atomic ratios α = X/M near 1 form glasses on evaporation. Herein, we describe the preparation and properties of these glasses and discuss the nature of the crystal-glass equilibria beyond the pure glass compositions. Small- and wide-angle X-ray scattering (SWAXS) studies reveal increased polymerization as α decreases from 2 to 1. The glasses are found to be much denser than their crystalline counterparts. Crystals forming in contact with glasses retain the well-known Zr-tetrameric hydroxo cluster unit with hydroxide compensating for the lowered halide content. We find that the chemical formulas for all of the solid hydroxohalides may be described by the single parameter α, according to the formula M(OH)4-αXα·(4α - 1)H2O. This description is valid for the crystalline chloride (MOX2·8H2O = M(OH)2X2·7H2O), the glassy solids with α < 2, and hydrolyzed products (α ≈ 0.5). The water content is also determined by α with hydroxide-hydrogen bonding replacing halide-hydrogen bonding as α decreases. A Eu3+-doped Zr,Cl glass exhibits photoluminescence transitions 5D0 → 7Fn (n = 1, 2, and 4) of Eu3+, illustrating the asymmetric nature of the dopant sites in the glass.

5.
Article in English | MEDLINE | ID: mdl-38151331

ABSTRACT

Ecologically mediated selection against hybrids, caused by hybrid phenotypes fitting poorly into available niches, is typically viewed as distinct from selection caused by epistatic Dobzhansky-Muller hybrid incompatibilities. Here, we show how selection against transgressive phenotypes in hybrids manifests as incompatibility. After outlining our logic, we summarize current approaches for studying ecology-based selection on hybrids. We then quantitatively review QTL-mapping studies and find traits differing between parent taxa are typically polygenic. Next, we describe how verbal models of selection on hybrids translate to phenotypic and genetic fitness landscapes, highlighting emerging approaches for detecting polygenic incompatibilities. Finally, in a synthesis of published data, we report that trait transgression-and thus possibly extrinsic hybrid incompatibility in hybrids-escalates with the phenotypic divergence between parents. We discuss conceptual implications and conclude that studying the ecological basis of hybrid incompatibility will facilitate new discoveries about mechanisms of speciation.

6.
bioRxiv ; 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38106000

ABSTRACT

Telomeres are nucleoprotein complexes with a crucial role of protecting chromosome ends. It consists of simple repeat sequences and dedicated telomere-binding proteins. Because of its vital functions, components of the telomere, for example its sequence, should be under strong evolutionary constraint. But across all plants, telomere sequences display a range of variation and the evolutionary mechanism driving this diversification is largely unknown. Here, we discovered in Monkeyflower (Mimulus) the telomere sequence is even variable between species. We investigated the basis of Mimulus telomere sequence evolution by studying the long noncoding telomerase RNA (TR), which is a core component of the telomere maintenance complex and determines the telomere sequence. We conducted total RNA-based de novo transcriptomics from 16 Mimulus species and analyzed reference genomes from 6 species, and discovered Mimulus species have evolved at least three different telomere sequences: (AAACCCT)n, (AAACCCG)n, and (AAACCG)n. Unexpectedly, we discovered several species with TR duplications and the paralogs had functional consequences that could influence telomere evolution. For instance, M. lewisii had two sequence-divergent TR paralogs and synthesized a telomere with sequence heterogeneity, consisting of AAACCG and AAACCCG repeats. Evolutionary analysis of the M. lewisii TR paralogs indicated it had arisen from a transposition-mediate duplication process. Further analysis of the TR from multiple Mimulus species showed the gene had frequently transposed and inserted into new chromosomal positions during Mimulus evolution. From our results, we propose the TR transposition, duplication, and divergence model to explain the evolutionary sequence turnovers in Mimulus and potentially all plant telomeres.

7.
New Phytol ; 240(6): 2210-2217, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37667567

ABSTRACT

Although intrinsic postzygotic reproductive barriers can play a fundamental role in speciation, their underlying evolutionary causes are widely debated. One hypothesis is that incompatibilities result from genomic conflicts. Here, I synthesize the evidence that conflict generates incompatibilities in plants, thus playing a creative role in plant biodiversity. While much evidence supports a role for conflict in several classes of incompatibility, integrating knowledge of incompatibility alleles with natural history can provide further essential tests. Moreover, comparative work can shed light on the relative importance of conflict in causing incompatibilities, including the extent to which their evolution is repeatable. Together, these approaches can provide independent lines of evidence that conflict causes incompatibilities, cementing its role in plant speciation.


Subject(s)
Genome , Plants , Plants/genetics , Genomics , Reproduction , Biodiversity , Hybridization, Genetic , Genetic Speciation
8.
J Correct Health Care ; 29(5): 338-346, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37733330

ABSTRACT

This study examined the impact of prompting only and prompting combined with independent group-oriented contingency on incarcerated adolescent males' physical activity level during a sport-leadership program. An alternating treatment design was employed to allow for the evaluation among multiple treatment conditions. The study occurred during 35 consecutive sport programming lessons at a juvenile correctional facility. Participants were 16 adolescent males (Mage = 18.79). Two behavior modification strategies, prompting only and prompting combined with independent group-oriented contingency, were employed. Data were plotted graphically so visual analysis could be determined in order to explore any functional associations between the treatment conditions (e.g., interventions) and target behavior (e.g., step count). Prompting only slightly increased physical activity, whereas prompting in conjunction with independent group-oriented contingency elevated activity levels by 36%, with a smaller standard deviation indicating that all participants were equivalently physically active. The results of this study underpin the expansive benefits of sport-leadership programming, not just in similar programs' ability to develop life skill integration, positively impact life during incarceration, improve attitudes, and promote physical activity, but also to provide elevated opportunities for youth to be physically active.

9.
J Pediatr ; 257: 113393, 2023 06.
Article in English | MEDLINE | ID: mdl-36940869

ABSTRACT

Our institution's annual bereaved family event was modified to a virtual format during the COVID-19 pandemic. While necessary to comply with physical distancing directives, the transition also provided greater accessibility for families. Virtual events were feasible and appreciated by attendees. Future hybrid bereavement events should be considered to allow families more flexibility and accessibility.


Subject(s)
Bereavement , COVID-19 , Humans , COVID-19/epidemiology , Pandemics
10.
Evolution ; 77(5): 1245-1261, 2023 04 27.
Article in English | MEDLINE | ID: mdl-36905222

ABSTRACT

Barriers to reproduction are often how progress in speciation is measured. Nonetheless, an unresolved question concerns the extent to which reproductive barriers diminish gene flow between incipient species. The Sierra Nevada foothill endemic Mimulus glaucescens and the widespread M. guttatus are considered distinct species based on striking differences in vegetative morphology, but barriers to reproduction have not been previously identified, nor has gene flow between species been characterized. Here, we examined 15 potential reproductive barriers within a Northern California area of broad sympatry. Most barriers, with the exception of ecogeographic isolation, were weak or absent, and total isolation for each species was incomplete. Population genomic analyses of range-wide and broadly sympatric accessions revealed extensive gene flow between these taxa, particularly in sympatry. Despite widespread introgression, Mimulus glaucescens, emerged as monophyletic and largely comprised a single ancestry that was found at intermediate frequency within M. guttatus. This result, along with observed ecological and phenotypic differentiation, suggests that natural selection may contribute to the maintenance of distinct phenotypic forms in the earliest stages of speciation. Integrating estimates of barrier strength with direct estimates of gene flow can strengthen a more nuanced interpretation of the process of speciation in natural communities.


Subject(s)
Mimulus , Reproductive Isolation , Mimulus/genetics , Gene Flow , Hybridization, Genetic , Reproduction , Sympatry , Genetic Speciation
11.
Am J Bot ; 110(3): 1-14, 2023 03.
Article in English | MEDLINE | ID: mdl-36801827

ABSTRACT

Understanding which reproductive barriers contribute to speciation is essential to understanding the diversity of life on earth. Several contemporary examples of strong hybrid seed inviability (HSI) between recently diverged species suggest that HSI may play a fundamental role in plant speciation. Yet, a broader synthesis of HSI is needed to clarify its role in diversification. Here, I review the incidence and evolution of HSI. Hybrid seed inviability is common and evolves rapidly, suggesting that it may play an important role early in speciation. The developmental mechanisms that underlie HSI involve similar developmental trajectories in endosperm, even between evolutionarily deeply diverged incidents of HSI. In hybrid endosperm, HSI is often accompanied by whole-scale gene misexpression, including misexpression of imprinted genes which have a key role in endosperm development. I explore how an evolutionary perspective can clarify the repeated and rapid evolution of HSI. In particular, I evaluate the evidence for conflict between maternal and paternal interests in resource allocation to offspring (i.e., parental conflict). I highlight that parental conflict theory generates explicit predictions regarding the expected hybrid phenotypes and genes responsible for HSI. While much phenotypic evidence supports a role of parental conflict in the evolution of HSI, an understanding of the underlying molecular mechanisms of this barrier is essential to test parental conflict theory. Lastly, I explore what factors may influence the strength of parental conflict in natural plant populations as an explanation for why rates of HSI may differ between plant groups and the consequences of strong HSI in secondary contact.


Subject(s)
Magnoliopsida , Magnoliopsida/genetics , Seeds/genetics , Endosperm/genetics , Plants , Hybridization, Genetic , Genetic Speciation
12.
Am Nat ; 201(1): 154-162, 2023 01.
Article in English | MEDLINE | ID: mdl-36524928

ABSTRACT

AbstractHybrid seed inviability is a common reproductive barrier in angiosperms. Recent work suggests that the rapid evolution of hybrid seed inviability may, in part, be due to conflict between maternal and paternal optima for resource allocation to developing offspring (i.e., parental conflict). However, parental conflict requires that paternally derived resource-acquiring alleles impose a maternal cost. I test this requirement using three closely related species in the Mimulus guttatus species complex that exhibit significant hybrid seed inviability and differ in their inferred histories of parental conflict. I show that the presence of hybrid seeds significantly affects conspecific seed size for almost all crosses, such that conspecific seeds are smaller after developing with hybrids sired by fathers with a stronger history of conflict and are larger after developing with hybrids sired by fathers with a weaker history of conflict. This work demonstrates a potential maternal cost of paternally derived alleles and also has implications for species fitness in secondary contact.


Subject(s)
Magnoliopsida , Seeds , Reproduction , Hybridization, Genetic
13.
Evol Lett ; 6(5): 344-357, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36254258

ABSTRACT

With the rise of affordable next-generation sequencing technology, introgression-or the exchange of genetic materials between taxa-has become widely perceived to be a ubiquitous phenomenon in nature. Although this claim is supported by several keystone studies, no thorough assessment of the frequency of introgression across eukaryotes in nature has been performed to date. In this manuscript, we aim to address this knowledge gap by examining patterns of introgression across eukaryotes. We collated a single statistic, Patterson's D, which can be used as a test for introgression across 123 studies to further assess how taxonomic group, divergence time, and sequencing technology influence reports of introgression. Overall, introgression has mostly been measured in plants and vertebrates, with less attention given to the rest of the Eukaryotes. We find that the most frequently used metrics to detect introgression are difficult to compare across studies and even more so across biological systems due to differences in study effort, reporting standards, and methodology. Nonetheless, our analyses reveal several intriguing patterns, including the observation that differences in sequencing technologies may bias values of Patterson's D and that introgression may differ throughout the course of the speciation process. Together, these results suggest the need for a unified approach to quantifying introgression in natural communities and highlight important areas of future research that can be better assessed once this unified approach is met.

14.
Mol Biol Evol ; 39(11)2022 11 03.
Article in English | MEDLINE | ID: mdl-36251862

ABSTRACT

Despite a century of genetic analysis, the evolutionary processes that have generated the patterns of exceptional genetic and phenotypic variation in the model organism Drosophila melanogaster remains poorly understood. In particular, how genetic variation is partitioned within its putative ancestral range in Southern Africa remains unresolved. Here, we study patterns of population genetic structure, admixture, and the spatial structuring of candidate incompatibility alleles across a global sample, including 223 new accessions, predominantly from remote regions in Southern Africa. We identify nine major ancestries, six that primarily occur in Africa and one that has not been previously described. We find evidence for both contemporary and historical admixture between ancestries, with admixture rates varying both within and between continents. For example, while previous work has highlighted an admixture zone between broadly defined African and European ancestries in the Caribbean and southeastern USA, we identify West African ancestry as the most likely African contributor. Moreover, loci showing the strongest signal of introgression between West Africa and the Caribbean/southeastern USA include several genes relating to neurological development and male courtship behavior, in line with previous work showing shared mating behaviors between these regions. Finally, while we hypothesized that potential incompatibility loci may contribute to population genetic structure across the range of D. melanogaster; these loci are, on average, not highly differentiated between ancestries. This work contributes to our understanding of the evolutionary history of a key model system, and provides insight into the partitioning of diversity across its range.


Subject(s)
Biological Evolution , Drosophila melanogaster , Animals , Drosophila melanogaster/genetics , Alleles , Africa , West Indies , Genetics, Population , Genetic Variation
15.
Am Nat ; 200(1): 168-180, 2022 07.
Article in English | MEDLINE | ID: mdl-35737985

ABSTRACT

AbstractThis essay explores shifting scientific understandings of fish and the evolution of fisheries science, and it grapples with colonialism as a system of power. We trace the rise of fisheries science to a time when Western nation-states were industrializing fishing fleets and competing for access to distant fishing grounds. A theory of fishing called "maximum sustainable yield" (MSY) that understands fish species in aggregate was espoused. Although alternatives to MSY have been developed, decision-making continues to be informed by statistical models developed within fisheries science. A challenge for structured management systems now rests in attending to different systems of knowledge and addressing local objectives, values, and circumstances. To deepen and illustrate key points, we examine Pacific herring (Clupea pallasii) and the expansion of commercial herring fisheries and state-led management in British Columbia, Canada. A feedback between colonialism and fisheries science is evident: colonialism generated the initial conditions for expansion and has been reinforced through the implementation of approaches and tools from fisheries science that define and quantify conservation in particular ways. Some features may be unique to the herring illustration, but important aspects of the feedback are more broadly generalizable. We propose three interconnected goals: (a) transform the siloed institutions and practices of Western science, (b) reimagine and rebuild pathways between information (including diverse values and perspectives) and decision-making, and (c) devolve governance authority and broaden governance processes such that multiple ways of knowing share equal footing.


Subject(s)
Colonialism , Fisheries , Animals , British Columbia , Conservation of Natural Resources , Feedback , Fishes , Humans , Models, Statistical
16.
Glob Health Res Policy ; 7(1): 5, 2022 02 11.
Article in English | MEDLINE | ID: mdl-35148788

ABSTRACT

BACKGROUND: Extensive health disparities exist for American Indian groups throughout the United States. Although insurance status is linked to important healthcare outcomes, this topic has infrequently been explored for American Indian tribes. For state-recognized tribes, who do not receive healthcare services through the Indian Health Service, this topic has yet to be explored. The purpose of this study is to explore how having limited access to health insurance (being uninsured or under-insured) impact American Indian women's healthcare experiences?. METHODS: In partnership with a community advisory board, this study used a qualitative description approach to conduct thirty-one semi-structured life-course interviews with American Indian women who are members of a state-recognized tribe in the Gulf Coast (United States) to explore their Western healthcare experiences. Interview were conducted at community centers, participant homes, and other locations identified by participants. Interviews were transcribed verbatim and findings were analyzed in NVivo using conventional content analysis. Findings were presented at tribal council meetings and to participants for member checking. RESULTS: Themes identified by participants included: (a) lack of insurance as a barrier to healthcare; (b) pre-paying for childbirth when uninsured; and (c) access to public health insurance coverage. Twenty-four women mentioned the role or importance of insurance in discussing their healthcare experiences, which was referenced a total of 59 times. CONCLUSION: These findings begin to fill an important gap in the literature about the health insurance experiences of American Indian tribal members. Not having insurance was an important concern for participants, particularly for elderly and pregnant tribal members. Not having insurance also kept tribal members from seeking healthcare services, and from getting needed prescriptions. In addition to promoting knowledge about, and expanding insurance options and enrollment, increased sovereignty and resources for state-recognized tribes is needed to address the health disparities experienced by American Indian groups.


Subject(s)
Health Services Accessibility , Medically Uninsured , Aged , Female , Humans , Insurance Coverage , Insurance, Health , Pregnancy , United States , American Indian or Alaska Native
17.
J Pharm Sci ; 111(4): 1012-1023, 2022 04.
Article in English | MEDLINE | ID: mdl-35139332

ABSTRACT

Subcutaneous (SubQ) injection is a common administration route for biotherapeutics. However, limited tools are available for understanding the dynamic relationships between drug products and resident cells following injection. Advances in tissue engineering have enabled the production of in vitro skin models that recapitulate the morphological structure and functional activity of human skin. Here we explore the use of a commercially available skin model to investigate potential immune activation in response to subcutaneously injected biotherapeutics. Exposure to high levels of a mixture of process-related impurities (that are known potent immune system activators) induced a robust immune response from the skin model, as indicated by enhanced metabolic activity and increased secretion of 19 cytokines and chemokines. The skin model also responded to aggregated antibodies (generated by extreme mechanical stirring and pH-jump stress, which resulted in orders of magnitude higher particle numbers than that found in products), as shown by the secretion of several signature cytokines (GM-CSF, RANTES, and MCP-1). However, the magnitude of the responses to the aggregates were significantly lower than the response to the impurities. These results highlight the promising utility of in vitro skin models for investigating the potential immune response to process-related impurities and biotherapeutic attributes in a subcutaneous environment. The use of skin models for assessing drug safety may provide new insights to help guide drug product and process development, and potentially mitigate the risk of injection site reactions and systemic immunogenic responses that may compromise the safety and efficacy of subcutaneously administered drugs.


Subject(s)
Cytokines , Skin , Antibodies , Cytokines/metabolism , Humans , Immunotherapy , Injections, Subcutaneous , Skin/metabolism
18.
Article in English | MEDLINE | ID: mdl-38770182

ABSTRACT

Access to healthcare is an essential component in addressing health disparities. However, the limitations of insurance coverage, and other barriers in paying for and accessing healthcare have seldom been researched for Indigenous peoples. In addition, state recognized tribes do not have access to the healthcare services provided by the Indian Health Service, and there is a need for research documenting their unique healthcare needs. Qualitative description was used to conduct 31 semi-structured interviews with women from an Indigenous tribe in the Gulf South to understand their experiences in paying for healthcare services. Participants described: (1) Discrimination Based on Perceived Ability to Pay for Healthcare; and (2) Limitations of Healthcare Coverage, with sub-themes (a) Difficulties Understanding Coverage Limitations; (b) Inadequate Coverage; and (c) Limited Choice of Providers. These findings indicate that state-recognized tribal members may need specialized insurance programs, and more comprehensive coverage of healthcare services and medications. Future actions should promote tribal sovereignty and increase access to healthcare resources for state-recognized tribes.

19.
Sex Roles ; 85(9-10): 499-514, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34955587

ABSTRACT

Research has shown that gender role attitudes influence a number of health-related outcomes, including intimate partner violence (IPV). Yet the gender role attitudes of Indigenous peoples - a population that experiences persistent health and violence disparities - have received scant scholarly attention. Using the Framework of Historical Oppression, Resilience, and Transcendence (FHORT), the purpose of this mixed methodology was to qualitatively explore U.S. Indigenous peoples' gender role attitudes and quantitatively examine how key social determinants of health, including IPV perpetration, historical oppression, and resilience, relate to gender role attitudes. This research integrates qualitative and quantitative data from two Southeastern tribes with a total of 563 unique data sources. Regression analysis revealed male sex and IPV victimization were associated with higher patriarchal gender role attitudes, while historical oppression and resilience were associated with lower patriarchal gender role attitudes. Resilience was also associated with lower "victim blaming." Ethnographic team-based data analysis methods revealed qualitative themes of patriarchal gender role attitudes and gendered socialization processes. This work highlights how key aspects of the FHORT might explain Indigenous peoples' patriarchal gender role attitudes, suggesting the need to redress historical oppression and patriarchal roles through decolonization.

20.
Proc Biol Sci ; 288(1948): 20210077, 2021 04 14.
Article in English | MEDLINE | ID: mdl-33823671

ABSTRACT

Ecological divergence is a fundamental source of phenotypic diversity between closely related species, yet the genetic architecture of most ecologically relevant traits is poorly understood. Differences in elevation can impose substantial divergent selection on both complex, correlated suites of traits (such as life-history), as well as novel adaptations. We use the Mimulus guttatus species complex to assess if the divergence in elevation is accompanied by trait divergence in a group of closely related perennials and determine the genetic architecture of this divergence. We find that divergence in elevation is associated with differences in life-history, as well as a unique trait, the production of rhizomes. The divergence between two perennials is largely explained by few mid-to-large effect quantitative trait loci (QTLs). However, the presence of QTLs with correlated, but opposing effects on multiple traits leads to some hybrids with transgressive trait combinations. Lastly, we find that the genetic architecture of the ability to produce rhizomes changes through development, wherein most hybrids produce rhizomes, but only later in development. Our results suggest that elevational differences may shape life-history divergence between perennials, but aspects of the genetic architecture of divergence may have implications for hybrid fitness in nature.


Subject(s)
Mimulus , Adaptation, Physiological , Mimulus/genetics , Phenotype , Quantitative Trait Loci
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