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1.
Proc Natl Acad Sci U S A ; 120(6): e2214729120, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716359

RESUMO

Understanding the processes that enable organisms to shift into more arid environments as they emerge is critical for gauging resilience to climate change, yet these forces remain poorly known. In a comprehensive clade-based study, we investigate recent shifts into North American deserts in the rock daisies (tribe Perityleae), a diverse tribe of desert sunflowers (Compositae). We sample rock daisies across two separate contact zones between tropical deciduous forest and desert biomes in western North America and infer a time-calibrated phylogeny based on target capture sequence data. We infer biome shifts using Bayesian inference with paleobiome-informed models and find evidence for seven independent shifts into desert habitats since the onset of aridification in the late Miocene. The earliest shift occurred out of tropical deciduous forests and led to an extensive radiation throughout North American deserts that accounts for the majority of extant desert rock daisies. Estimates of life history and micro-habitat in the rock daisies reveal a correlation between a suffrutescent perennial life history and edaphic endemism onto rocky outcrops, an ecological specialization that evolved prior to establishment and diversification in deserts. That the insular radiation of desert rock daisies stemmed from ancestors preadapted for dry conditions as edaphic endemics in otherwise densely vegetated tropical deciduous forests in northwest Mexico underscores the crucial role of exaptation and dispersal for shifts into arid environments.


Assuntos
Asteraceae , Magnoliopsida , Teorema de Bayes , Clima Desértico , Filogenia , Ecossistema
2.
Gynecol Oncol ; 188: 8-12, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38861918

RESUMO

OBJECTIVE: To examine endometrial cancer survivors' access to healthy food resources recommended by the Society of Gynecologic Oncology (SGO) in relation to food deserts and social health determinants. METHODS: Participants included women seen for endometrial cancer treatment at an academic medical center in the Deep South from 2015 to 2020 who lived in South Carolina. Demographic and comorbidity data were abstracted from medical records. Food desert data were obtained from the United States Department of Agriculture (USDA). Each patient was assigned a socioeconomic (SES) score (SES-1 = low, SES-5 = high) using census data and a social vulnerability index (SVI) using Center for Disease Control and Prevention (CDC) data for neighborhood adverse health effects. Geospatial techniques assessed patients' driving distance from home to a healthy food resource. RESULTS: Of the 736 endometrial cancer survivors, 31% identified as African American, and 30% lived in low SES (SES-1, SES-2) census blocks. Most survivors had low grade disease (63%) and 76% with stage 1-2 disease. Seventy percent of patients were obese (BMI ≥30 kg/m2). Forty percent of survivors lived in a food desert. Survivors living in a food desert with low SES had significantly higher social vulnerability (p = 0.0001) and lower median income (p = 0.0001). Those with low SES and living in a food desert drove further (p = 0.05, range 0.017-12.0 miles). CONCLUSION: Obesity rates were high in endometrial cancer survivors living in the Deep South. Survivors with higher social vulnerability and lower SES were more likely to live in food deserts with decreased access to healthy food resources.


Assuntos
Sobreviventes de Câncer , Neoplasias do Endométrio , Desertos Alimentares , População Rural , Humanos , Feminino , Neoplasias do Endométrio/epidemiologia , Sobreviventes de Câncer/estatística & dados numéricos , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Idoso , South Carolina/epidemiologia , Análise Espacial , Abastecimento de Alimentos/estatística & dados numéricos , Adulto , Fatores Socioeconômicos , Dieta Saudável/estatística & dados numéricos
3.
BMC Pregnancy Childbirth ; 24(1): 350, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720255

RESUMO

BACKGROUND: Access to maternity care in the U.S. remains inequitable, impacting over two million women in maternity care "deserts." Living in these areas, exacerbated by hospital closures and workforce shortages, heightens the risks of pregnancy-related complications, particularly in rural regions. This study investigates travel distances and time to obstetric hospitals, emphasizing disparities faced by those in maternity care deserts and rural areas, while also exploring variances across races and ethnicities. METHODS: The research adopted a retrospective secondary data analysis, utilizing the American Hospital Association and Centers for Medicaid and Medicare Provider of Services Files to classify obstetric hospitals. The study population included census tract estimates of birthing individuals sourced from the U.S. Census Bureau's 2017-2021 American Community Survey. Using ArcGIS Pro Network Analyst, drive time and distance calculations to the nearest obstetric hospital were conducted. Furthermore, Hot Spot Analysis was employed to identify areas displaying significant spatial clusters of high and low travel distances. RESULTS: The mean travel distance and time to the nearest obstetric facility was 8.3 miles and 14.1 minutes. The mean travel distance for maternity care deserts and rural counties was 28.1 and 17.3 miles, respectively. While birthing people living in rural maternity care deserts had the highest average travel distance overall (33.4 miles), those living in urban maternity care deserts also experienced inequities in travel distance (25.0 miles). States with hotspots indicating significantly higher travel distances included: Montana, North Dakota, South Dakota, and Nebraska. Census tracts where the predominant race is American Indian/Alaska Native (AIAN) had the highest travel distance and time compared to those of all other predominant races/ethnicities. CONCLUSIONS: Our study revealed significant disparities in obstetric hospital access, especially affecting birthing individuals in maternity care deserts, rural counties, and communities predominantly composed of AIAN individuals, resulting in extended travel distances and times. To rectify these inequities, sustained investment in the obstetric workforce and implementation of innovative programs are imperative, specifically targeting improved access in maternity care deserts as a priority area within healthcare policy and practice.


Assuntos
Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Maternidades , Serviços de Saúde Materna , Humanos , Estados Unidos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Feminino , Gravidez , Estudos Retrospectivos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Disparidades em Assistência à Saúde/etnologia , Serviços de Saúde Materna/estatística & dados numéricos , Maternidades/estatística & dados numéricos , Viagem/estatística & dados numéricos , População Rural/estatística & dados numéricos
4.
Appetite ; 197: 107305, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521414

RESUMO

Effective ways to promote healthful food intake in rural areas are understudied. The paper evaluated whether a two-component, in-store intervention designed to encourage healthy food purchases was associated with improved healthfulness scores of food items purchased by shoppers in rural food deserts. One component introduced a point-of-sales label that assigned a single numerical score to each food item facilitating direct comparisons of the product's nutrition with those of other products shelved around it. The other component was a one-day nutrition education workshop promoted within the store. Interventions took place in 2015 at two stores in rural counties in the U.S. Midwest. Four stores in similar communities were selected as the control group. We applied a difference-in-difference model to estimate changes in the healthfulness of food items purchased attributable to the intervention among shoppers at the treatment stores (n = 486) and control stores (n = 10,759) using store transaction data. Healthfulness of food items was measured in terms of food scores published by the Environmental Working Group on a 1-10 scale. Both components had minimal impacts on the scores, although 0.2 and 0.1 points increases in the score per item and score per dollar were statistically significant at the 1% level respectively. A year after the intervention, these small effects of the intervention further diminished compared to the immediately after implementation. Results suggest the average effects of intervention across the study communities had limited practical significance but benefited some rural residents who were exposed to the intervention.


Assuntos
Desertos Alimentares , Alimentos Especializados , Humanos , Abastecimento de Alimentos , Preferências Alimentares , Educação em Saúde , Comércio
5.
Postgrad Med J ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39323384

RESUMO

"Medical deserts" are areas with low healthcare service levels, challenging the access, quality, and sustainability of care. This qualitative narrative review examines how artificial intelligence (AI), particularly large language models (LLMs), can address these challenges by integrating with e-Health and the Internet of Medical Things to enhance services in under-resourced areas. It explores AI-driven telehealth platforms that overcome language and cultural barriers, increasing accessibility. The utility of LLMs in providing diagnostic assistance where specialist deficits exist is highlighted, demonstrating AI's role in supplementing medical expertise and improving outcomes. Additionally, the development of AI chatbots offers preliminary medical advice, serving as initial contact points in remote areas. The review also discusses AI's role in enhancing medical education and training, supporting the professional development of healthcare workers in these regions. It assesses AI's strategic use in data analysis for effective resource allocation, identifying healthcare provision gaps. AI, especially LLMs, is seen as a promising solution for bridging healthcare gaps in "medical deserts," improving service accessibility, quality, and distribution. However, continued research and development are essential to fully realize AI's potential in addressing the challenges of medical deserts.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38836414

RESUMO

CONTEXT: The organization of primary care in France has long remained a secondary issue on the political agenda. The government began to address the difficulties of care access and coordination in the 2000s, when a seemingly viable solution emerged from the field: the Maisons de Santé Pluriprofessionnelles (MSPs). In a corporatist system and a predominantly private sector, the government chose an incentive-based, contractual policy to encourage providers to join these structures. This article analyzes the implementation of this policy which depends on private providers' commitment. METHODS: The article offers a comparative case study of six MSPs. Data were collected through semi-structured interviews, observation sessions, and document analysis. FINDINGS: First, the article shows that the emergence of MSPs has only been possible thanks to an unprecedented alliance between GPs, the state, and the health insurance fund. Second, it argues that MSP policy's implementation relies on a complex bargaining process between private providers and public authorities that enables the former to shape it to their local needs. CONCLUSIONS: MSP implementation experiences raise questions both about the understanding of medical corporatism in France and the assimilation of policy changes and local variation through implementation.

7.
Ecol Food Nutr ; 63(5): 564-584, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39097942

RESUMO

Food security among rural veteran populations is an understudied subject. This study uses qualitative data from 106 semi-structured interviews conducted with staff from programs at the United States Department of Veterans Affairs (VA) and other federal agencies, staff from non-governmental organizations (NGOs), food security researchers, and food insecure veterans to identify the barriers to and facilitators for rural veteran food security. Barriers identified included external, structural barriers that exist in rural areas; internal barriers to using food assistance, such as feeling stigmatized; and barriers related to other social determinants of health, including a lack of education, employment, or housing stability.


Assuntos
Assistência Alimentar , Insegurança Alimentar , População Rural , Veteranos , Humanos , Estados Unidos , Abastecimento de Alimentos , Masculino , Feminino , Determinantes Sociais da Saúde , United States Department of Veterans Affairs
8.
Arch Microbiol ; 205(3): 90, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36780035

RESUMO

The Kyzyl-Kum Desert extends over an area of 300,000 Km2, in the region bordering Kazakhstan, Uzbekistan and Turkmenistan and is mainly covered by sand dunes. The Kyzyl-Kum desert is also known for its large deposits of minerals of economic interests, the exploitation of which is affecting the local ecosystem and increasing the desertification. We examined the bacterial biodiversity of surface sand samples from several sites from the Kyzyl-Kum desert using pyrosequencing of PCR amplified bacterial 16S rRNA genes from total extracted soil DNA. We also examined several physicochemical parameters of the sand samples to investigate any possible correlations between bacterial community structure and environmental drivers. The predominant bacterial phyla present in the samples were found to belong to members of the Actinobacteria, Proteobacteria and Bacteroidetes. The most abundant genera in our samples were found to belong to the Arthrobacter, Adhaeribacter and Roseomonas genera. We found that the relative abundance of members belonging to the Actinobacteria phylum, commonly found in desertic areas, increase in abundance in sites with higher content of organic matter and sulfur, whereas members of the Proteobacteria and Bacteroidetes phyla seems to diminish in abundance in coarse silt and fine-grained soils and those rich in magnesium, suggesting that those parameters might influence the bacterial community composition in this desertic area. This study is the first to provide new insights into the prokaryotic community composition from this unusual desert site.


Assuntos
Microbiota , Areia , Uzbequistão , RNA Ribossômico 16S/genética , Clima Desértico , Bactérias/genética , Proteobactérias , Biodiversidade , Microbiota/genética , Bacteroidetes/genética , Genômica , Microbiologia do Solo , Solo/química
9.
J Urban Health ; 100(5): 950-961, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37605103

RESUMO

The COVID-19 pandemic has dramatically altered people's lives in multiple aspects, including grocery shopping behaviors. Yet, the changing trend of grocery shopping frequencies during the COVID-19 and its associations with food deserts remain unclear. We aimed to (1) examine variations of grocery shopping frequencies at county level in the USA during the COVID-19 pandemic from March 2020 to December 2021; (2) investigate associations between grocery shopping frequencies and food deserts during the COVID-19 pandemic; and (3) explore heterogeneity in grocery shopping frequencies-food desert associations across urban and rural areas. The county-level grocery shopping frequencies were derived from a grocery pattern dataset obtained from SafeGraph. We divided the 22-month period into 5 stages and employed the growth curve modeling to estimate the trajectories of grocery shopping frequencies and the associations between grocery shopping frequencies and food deserts in each stage, separately. Results revealed that grocery shopping frequencies experienced a "W-shaped" pattern from March 2020 to December 2021. Counties with the least percent of food deserts had slower decrease in grocery shopping frequencies at the initial stage and recovered more rapidly at later stages. Counties with the highest percent of food deserts were subject to deprivation amplification as a result of the pandemic. We also found differences existed in the grocery shopping frequencies-food desert associations between metropolitan counties and rural counties. Our findings suggest the impacts of COVID-19 on grocery shopping frequencies varied across different time periods, shedding light on designing different strategies to reduce the risk of contagion while shopping inside of grocery stores. Further, our findings highlight an urgent need to help people living in food deserts (especially in rural counties) to procure healthy foods safely during health emergencies like COVID-19 pandemic which disrupt mobility and social behaviors.


Assuntos
COVID-19 , Desertos Alimentares , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , Pandemias , Abastecimento de Alimentos , Alimentos
10.
BMC Public Health ; 23(1): 120, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650487

RESUMO

BACKGROUND: Previous research suggests that unhealthy community food environments around schools contribute to unhealthy eating habits and negative health outcomes among the youth. However, little is known about how socioeconomic inequalities in those community food environments are associated with food deserts and food swamps across schools' neighborhoods. METHODS: An ecological study was carried out in all 3,159 public and private schools in Rio de Janeiro, Brazil. Three measures of socioeconomic inequality were evaluated: per capita income, segregation index and deprivation index. The community school food environment was analyzed by metrics of food swamps and food deserts. RESULTS: Food deserts and food swamps were simultaneously more prevalent in neighborhoods of the lowest income, high deprivation, and high segregation. Spatial socioeconomic disparities at the neighborhoods of schools were associated with food deserts and food swamps in Rio de Janeiro. CONCLUSIONS: Our results point to a spatial socioeconomic inequality of establishments that sell food around schools in a Brazilian metropolis, indicating that the areas of greatest deprivation of food services are also the areas with the worst socioeconomic characteristics.


Assuntos
Desertos Alimentares , Áreas Alagadas , Adolescente , Humanos , Brasil , Fatores Socioeconômicos , Instituições Acadêmicas , Características de Residência
11.
Violence Vict ; 38(3): 435-456, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37348956

RESUMO

While there is substantial public health literature that documents the negative impacts of living in "food deserts" (e.g., obesity and diabetes), little is known regarding whether living in a food desert is associated with increased criminal victimization. With the block group as the unit of analysis, the present study examines whether there is a relationship between food deserts and elevated crime counts, and whether this relationship varies by racial composition. Results from multiple count models suggest that living in a food desert is not associated with higher levels of violent or property crime. But multiplicative models interacting percent Black with food deserts revealed statistically significant associations with violent crime but not property crime. Alternatively, multiplicative models interacting percent White with food deserts revealed statistically significant associational reductions in violent crimes. Several policy and research implications are discussed.


Assuntos
Vítimas de Crime , Desertos Alimentares , Humanos , Violência , Crime , Agressão
12.
Rural Remote Health ; 23(1): 7477, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36854290

RESUMO

INTRODUCTION: Despite policies aiming at universal health coverage by ensuring availability and accessibility of general practitioners (GPs), medically underserved areas are still present in Europe. This systematic review aims to summarize and compare literature on interventions and their potential effectiveness of GP recruitment and retention in these underserved areas ('medical deserts') from 2011 onwards. METHODS: PubMed and Embase were used to identify publications, applying a two-stage selection process. All types of study designs, published in the past 10 years, were included if they discussed a possible intervention for GP recruitment or retention covering an underserved area in an EU-27/EEA/EFTA country (part of the European Union, the European Economic Area or the European Free Trade Association). Exclusion criteria were abstracts or full text not available, conference abstracts, poster presentations, books or overlapping secondary literature. Identified interventions were classified into four categories: 'education', 'professional and personal support', 'financial incentives' and 'regulation'. Eligible articles were critically appraisal by two authors (JB, LF), independently, by using the Joanna Briggs Institute checklist. RESULTS: Of the 294 publications initially retrieved, 25 publications were included. Of them, 14 (56%) described educational interventions, 13 (52%) professional and personal support, and 11 (40%) financial or regulatory interventions. Overlapping categories were often described (56%). The effectiveness of educational or supportive interventions has mainly been evaluated cross-sectionally, whereby causal inference on future GP availability cannot be implied. Few and mixed results were found for the effectiveness of financial and regulatory interventions, because period co-interventions were not taken into account during the study. CONCLUSION: In the past 10 years, educational and supportive interventions to improve GP recruitment and retention have been reported most frequently, but often overlapping strategies are seen. While multiple strategies have potential to be effective, their limited evaluation makes it difficult to provide suggestions for policymakers to adapt their GP recruitment and retention strategies aiming at a best-practice approach in European medical deserts.


Assuntos
Clínicos Gerais , Humanos , Escolaridade , Área Carente de Assistência Médica
13.
Dokl Biol Sci ; 506(1): 212-238, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36301431

RESUMO

For the polar deserts of the Novaya Zemlya archipelago, the analysis of the dependence of the distribution of lichens on altitude above sea level, exposure by cardinal direction, the granulometric composition of soils, morphometric parameters of structural soils, the cover values of bryophytes and the total cover of cushion forms of plants and lichens was carried out. Based on 157 sample plots, nine lichenocenotypes (lichen community formed in a specific type of habitat) were identified. It is shown that with increasing height (during the transition from zonal to orozonal positions), the cover and the number of lichen species decrease. The cover of lichens also decreases with an increase in the cover of mosses. With an increase in the content of a fraction in soils of more than 0.125 mm, the species diversity and the cover of lichens increases. A total of 84 lichen species were identified, of which Thamnolia vermicularis s. l. is classified as the most active, nine are highly active, 11-medium-active, the rest are little active and inactive. The current pattern of lichen distribution in the landscape of the far North of Novaya Zemlya is largely due to historical reasons-the youth of the landscape, recently freed from the ice cover, an exceptionally high degree of mobility of the cover of loose Quaternary deposits.


Assuntos
Briófitas , Líquens , Ecossistema , Solo , Plantas
14.
Mol Biol Evol ; 37(10): 2857-2864, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32421818

RESUMO

We investigated how the two rounds of whole-genome duplication that occurred at the base of the vertebrate lineage have impacted ancient microsyntenic associations involving developmental regulators (known as genomic regulatory blocks, GRBs). We showed that the majority of GRBs identified in the last common ancestor of chordates have been maintained as a single copy in humans. We found evidence that dismantling of the duplicated GRB copies occurred early in vertebrate evolution often through the differential retention of the regulatory gene but loss of the bystander gene's exonic sequences. Despite the large evolutionary scale, the presence of duplicated highly conserved noncoding regions provided unambiguous proof for this scenario for multiple ancient GRBs. Remarkably, the dismantling of ancient GRB duplicates has contributed to the creation of large gene deserts associated with regulatory genes in vertebrates, providing a potentially widespread mechanism for the origin of these enigmatic genomic traits.


Assuntos
Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Genes Reguladores , Poliploidia , Vertebrados/genética , Animais , Duplicação Cromossômica , Genoma Humano , Humanos , Elementos Reguladores de Transcrição
15.
New Phytol ; 230(3): 1228-1241, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33460447

RESUMO

There are multiple hypotheses for the spectacular plant diversity found in deserts. We explore how different factors, including the roles of ecological opportunity and selection, promote diversification and disparification in Encelia, a lineage of woody plants in the deserts of the Americas. Using a nearly complete species-level phylogeny based on double-digest restriction-aided sequencing along with a broad set of phenotypic traits, we estimate divergence times and diversification rates, identify instances of hybridization, quantify trait disparity and assess phenotypic divergence across environmental gradients. We show that Encelia originated and diversified recently (mid-Pleistocene) and rapidly, with rates comparable to notable adaptive radiations in plants. Encelia probably originated in the hot deserts of North America, with subsequent diversification across steep environmental gradients. We uncover multiple instances of gene flow between species. The radiation of Encelia is characterized by fast rates of phenotypic evolution, trait lability and extreme disparity across environments and between species pairs with overlapping geographic ranges. Encelia exemplifies how interspecific gene flow in combination with high trait lability can enable exceptionally fast diversification and disparification across steep environmental gradients.


Assuntos
Asteraceae , Hibridização Genética , Evolução Biológica , Fluxo Gênico , América do Norte , Filogenia
16.
J Phycol ; 57(3): 886-902, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33583028

RESUMO

Cyanobacteria are crucial ecosystem components in dryland soils. Advances in describing α-level taxonomy are needed to understand what drives their abundance and distribution. We describe Trichotorquatus gen. nov. (Oculatellaceae, Synechococcales, Cyanobacteria) based on four new species isolated from dryland soils including the coastal sage scrub near San Diego, California (USA), the Mojave and Colorado Deserts with sites at Joshua Tree National Park and Mojave National Preserve, California (USA), and the Atacama Desert (Chile). The genus is morphologically characterized by having thin trichomes (<4.5 µm wide), cells both shorter and longer than wide, rarely occurring single and double false branching, necridia appearing singly or in rows, and sheaths with a distinctive collar-like fraying and widening mid-filament, the feature for which the genus is named. The genus is morphologically nearly identical with Leptolyngbya sensu stricto but is phylogenetically quite distant from that genus. It is consequently a cryptic genus that will likely be differentiated in future studies based on 16S rRNA sequence data. The type species, T. maritimus sp. nov. is morphologically distinct from the other three species, T. coquimbo sp. nov., T. andrei sp. nov. and T. ladouxae sp. nov. However, these latter three species are morphologically very close and are considered by the authors to be cryptic species. All species are separated phylogenetically based on sequence of the 16S-23S ITS region. Three distinct ribosomal operons were recovered from the genus, lending difficulty to recognizing further diversity in this morphologically cryptic genus.


Assuntos
Cianobactérias , Ecossistema , Técnicas de Tipagem Bacteriana , Chile , Colorado , Cianobactérias/genética , DNA Bacteriano , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Solo , Estados Unidos
17.
Food Policy ; 99: 101985, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33082618

RESUMO

Many U.S. households lack access to healthful food and rely on inexpensive, processed food with low nutritional value. Surveying access to healthful food is costly and finding the factors that affect access remains convoluted owing to the multidimensional nature of socioeconomic variables. We utilize machine learning with census tract data to predict the modified Retail Food Environment Index (mRFEI), which refers to the percentage of healthful food retailers in a tract and agnostically extract the features of no access-corresponding to a "food desert" and low access-corresponding to a "food swamp." Our model detects food deserts and food swamps with a prediction accuracy of 72% out of the sample. We find that food deserts and food swamps are intrinsically different and require separate policy attention. Food deserts are lightly populated rural tracts with low ethnic diversity, whereas swamps are predominantly small, densely populated, urban tracts, with more non-white residents who lack vehicle access. Overall access to healthful food retailers is mainly explained by population density, presence of black population, property value, and income. We also show that our model can be used to obtain sensible predictions of access to healthful food retailers for any U.S. census tract.

18.
BMC Evol Biol ; 20(1): 26, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054437

RESUMO

BACKGROUND: Climatic variation and geologic change both play significant roles in shaping species distributions, thus affecting their evolutionary history. In Sahara-Sahel, climatic oscillations shifted the desert extent during the Pliocene-Pleistocene interval, triggering the diversification of several species. Here, we investigated how these biogeographical and ecological events have shaped patterns of genetic diversity and divergence in African Jerboas, desert specialist rodents. We focused on two sister and cryptic species, Jaculus jaculus and J. hirtipes, where we (1) evaluated their genetic differentiation, (2) reconstructed their evolutionary and demographic history; (3) tested the level of gene flow between them, and (4) assessed their ecological niche divergence. RESULTS: The analyses based on 231 individuals sampled throughout North Africa, 8 sequence fragments (one mitochondrial and seven single copy nuclear DNA, including two candidate genes for fur coloration: MC1R and Agouti), 6 microsatellite markers and ecological modelling revealed: (1) two distinct genetic lineages with overlapping distributions, in agreement with their classification as different species, J. jaculus and J. hirtipes, with (2) low levels of gene flow and strong species divergence, (3) high haplotypic diversity without evident geographic structure within species, and (4) a low level of large-scale ecological divergence between the two taxa, suggesting species micro-habitat specialization. CONCLUSIONS: Overall, our results suggest a speciation event that occurred during the Pliocene-Pleistocene transition. The contemporary distribution of genetic variation suggests ongoing population expansions. Despite the largely overlapping distributions at a macrogeographic scale, our genetic results suggest that the two species remain reproductively isolated, as only negligible levels of gene flow were observed. The overlapping ecological preferences at a macro-geographic scale and the ecological divergence at the micro-habitat scale suggest that local adaptation may have played a crucial role in the speciation process of these species.


Assuntos
Especiação Genética , Roedores/classificação , Roedores/genética , África do Norte , Animais , Evolução Biológica , DNA Mitocondrial/genética , Ecologia , Ecossistema , Meio Ambiente , Variação Genética , Haplótipos , Filogenia , Filogeografia
19.
Am J Bot ; 106(10): 1327-1345, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31545882

RESUMO

PREMISE: Although numerous phylogenetic studies have been conducted in Cactaceae, whole-plastome datasets have not been employed. We used the chollas to develop a plastome dataset for phylogeny reconstruction to test species relationships, biogeography, clade age, and morphological evolution. METHODS: We developed a plastome dataset for most known diploid members of the chollas (42 taxa) as well as for other members of Cylindropuntieae. Paired-end, raw reads from genome skimming were reference-mapped onto a de novo plastome assembly of one species of cholla, Cylindropuntia bigelovii, and were used to build our plastome dataset, which was analyzed using various methods. RESULTS: Our plastome dataset resolved the phylogeny of the chollas, including most interspecific and intraspecific relationships. Tribe Cylindropuntieae arose ~18 mya, during the early Miocene in southern South America, and is supported as sister to the South American clade Tephrocacteae. The (Micropuntia (Cylindropuntia + Grusonia)) clade most likely originated in the Chihuahuan Desert region around 16 mya and then migrated into other North American desert regions. Key morphological characters for recognizing traditional taxonomic series in Cylindropuntia (e.g., spiny fruit) are mostly homoplasious. CONCLUSIONS: This study provides the first comprehensive plastome phylogeny for any clade within Cactaceae. Although the chollas s.l. are widespread throughout western North American deserts, their most recent common ancestor likely arose in the Chihuahuan Desert region during the mid-Miocene, with much of their species diversity arising in the early to mid-Pliocene, a pattern strikingly similar to those found in other western North American desert groups.


Assuntos
Cactaceae , Diploide , Filogenia , Análise de Sequência de DNA , América do Sul
20.
Ecol Food Nutr ; 58(1): 3-22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30522356

RESUMO

We sought to collect information about the operations of wholesalers and store owner perceptions of smartphones to plan for and create a smartphone application that will facilitate the distribution of healthy foods to corner stores. In-depth interviews were conducted with wholesalers, corner store owners, distributors, and food environment experts in Baltimore City, Maryland, which included providing feedback for a mockup of the app. Store owners that were comfortable with smartphones liked the idea of the app because it was economically practical, culturally suitable, simple and easy to use, and provided a large variety of items at a fair or low price. We found that barriers to uptake among corner store owners would be high delivery costs, no foreign language capability, and a complicated user interface. This work will inform future projects that will utilize mHealth technology to improve distribution of healthier foods in food deserts.


Assuntos
Dieta Saudável/métodos , Abastecimento de Alimentos/instrumentação , Áreas de Pobreza , Pobreza , Smartphone , Baltimore , Alfabetização Digital , Abastecimento de Alimentos/normas , Entrevistas como Assunto , Pobreza/economia
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