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1.
JAMA Netw Open ; 6(4): e239995, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37099296

RESUMO

Importance: There were over 45 000 suicides in the US in 2020, making suicide the 12th leading cause of death. If social vulnerability is associated with suicide rates, targeted interventions for at-risk segments of the population may reduce US suicide rates. Objective: To determine the association between social vulnerability and suicide in adults. Design, Setting, and Participants: This cohort study analyzed 2 county-level social vulnerability measures (the Social Vulnerability Index [SVI] and the Social Vulnerability Metric [SVM]) and US Centers for Disease Control and Prevention-reported county-level suicides from 2016 to 2020. Data were analyzed November and December 2022. Exposures: County-level variability in social vulnerability. Main Outcomes and Measures: The primary outcome measure was number of county-level adult suicides from 2016 to 2020, offset by county adult population during those years. The association between social vulnerability (measured using the SVI and the newly created SVM for 2018) and suicide was modeled using a bayesian-censored Poisson regression model to account for the CDC's suppression of county-level suicide counts of less than 10, adjusted for age, racial and ethnic minority, and urban-rural county characteristics. Results: From 2016 to 2020, there were a total of 222 018 suicides in 3141 counties. Comparing the least socially vulnerable (0% to 10%) to the most socially vulnerable (90% to 100%) counties, there was a 56% increase in suicide rate (17.3 per 100 000 persons to 27.0 per 100 000 persons) as measured by the SVI (incidence rate ratio, 1.56; 95% credible interval, 1.51-1.60) and an 82% increase in suicide rate (13.8 per 100 000 persons to 25.1 per 100 000 persons) as measured by the SVM (incidence rate ratio, 1.82; 95% credible interval, 1.72-1.92). Conclusions and Relevance: This cohort study found that social vulnerability had a direct association with risk for adult suicide. Reducing social vulnerability may lead to life-saving reduction in the rate of suicide.


Assuntos
Suicídio , Humanos , Adulto , Etnicidade , Vulnerabilidade Social , Estudos de Coortes , Teorema de Bayes , Grupos Minoritários
2.
Langmuir ; 38(49): 15272-15281, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36454950

RESUMO

The growing interest in integrating liquid crystals (LCs) into flexible and miniaturized technologies brings about the need to understand the interplay between spatially curved geometry, surface anchoring, and the order associated with these materials. Here, we integrate experimental methods and computational simulations to explore the competition between surface-induced orientation and the effects of deformable curved boundaries in uniaxially and biaxially stretched nematic and smectic microdroplets. We find that the director field of the nematic LCs upon uniaxial strain reorients and forms a larger twisted defect ring to adjust to the new deformed geometry of the stretched droplet. Upon biaxial extension, the director field initially twists in the now oblate geometry and subsequently transitions into a uniform vertical orientation at high strains. In smectic microdroplets, on the other hand, LC alignment transforms from a radial smectic layering to a quasi-flat layering in a compromise between interfacial and dilatation forces. Upon removing the mechanical strain, the smectic LC recovers its initial radial configuration; however, the oblate geometry traps the nematic LC in the metastable vertical state. These findings offer a basis for the rational design of LC-based flexible devices, including wearable sensors, flexible displays, and smart windows.

3.
Nat Commun ; 13(1): 5279, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127334

RESUMO

By darkening the snow surface, mineral dust and black carbon (BC) deposition enhances snowmelt and triggers numerous feedbacks. Assessments of their long-term impact at the regional scale are still largely missing despite the environmental and socio-economic implications of snow cover changes. Here we show, using numerical simulations, that dust and BC deposition advanced snowmelt by 17 ± 6 days on average in the French Alps and the Pyrenees over the 1979-2018 period. BC and dust also advanced by 10-15 days the peak melt water runoff, a substantial effect on the timing of water resources availability. We also demonstrate that the decrease in BC deposition since the 1980s moderates the impact of current warming on snow cover decline. Hence, accounting for changes in light-absorbing particles deposition is required to improve the accuracy of snow cover reanalyses and climate projections, that are crucial for better understanding the past and future evolution of mountain social-ecological systems.


Assuntos
Mudança Climática , Neve , Carbono , Poeira/análise , Fuligem , Água
4.
Transbound Emerg Dis ; 69(5): 3056-3065, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34427399

RESUMO

Bovine coronavirus (BCoV) is associated with three distinct clinical syndromes in cattle that is, neonatal diarrhoea, haemorrhagic diarrhoea in adults (the so-called winter dysentery syndrome, WD) and respiratory infections in cattle of different ages. In addition, bovine-like CoVs have been detected in various species including domestic and wild ruminants. However, bovine-like CoVs have not been reported so far in odd-toed ungulates. We describe an outbreak of WD associated with a bovine-like CoV affecting several captive wild ungulates, including Indonesian tapirs (Acrocodia indica) an odd-toed ungulate species (Perissodactyla) which, with even-toed ungulates species (Artiodactyla) form the clade Euungulata. Genomic characterization of the CoV revealed that it was closely related to BCoVs previously reported in America. This case illustrates the adaptability of bovine-like CoVs to new species and the necessity of continued surveillance of bovine-like CoVs in various species.


Assuntos
Doenças dos Bovinos , Infecções por Coronavirus , Coronavirus Bovino , Coronavirus , Disenteria , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Coronavirus/genética , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Coronavirus Bovino/genética , Diarreia/epidemiologia , Diarreia/veterinária , Surtos de Doenças/veterinária , Disenteria/epidemiologia , Disenteria/veterinária , Genômica , Indonésia/epidemiologia , Perissodáctilos , Filogenia , Ruminantes
5.
Proc Natl Acad Sci U S A ; 118(44)2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34697237

RESUMO

Snow is highly sensitive to atmospheric warming. However, because of the lack of sufficiently long snow avalanche time series and statistical techniques capable of accounting for the numerous biases inherent to sparse and incomplete avalanche records, the evolution of process activity in a warming climate remains little known. Filling this gap requires innovative approaches that put avalanche activity into a long-term context. Here, we combine extensive historical records and Bayesian techniques to construct a 240-y chronicle of snow avalanching in the Vosges Mountains (France). We show evidence that the transition from the late Little Ice Age to the early twentieth century (i.e., 1850 to 1920 CE) was not only characterized by local winter warming in the order of +1.35 °C but that this warming also resulted in a more than sevenfold reduction in yearly avalanche numbers, a severe shrinkage of avalanche size, and shorter avalanche seasons as well as in a reduction of the extent of avalanche-prone terrain. Using a substantial corpus of snow and climate proxy sources, we explain this abrupt shift with increasingly scarcer snow conditions with the low-to-medium elevations of the Vosges Mountains (600 to 1,200 m above sea level [a.s.l.]). As a result, avalanches migrated upslope, with only a relict activity persisting at the highest elevations (release areas >1,200 m a.s.l.). This abrupt, unambiguous response of snow avalanche activity to warming provides valuable information to anticipate likely changes in avalanche behavior in higher mountain environments under ongoing and future warming.

6.
Clim Serv ; 22: 100215, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34239989

RESUMO

Ski tourism plays a major socio-economic role in the snowy and mountainous areas of Europe such as the Alps, the Pyrenees, Nordic Europe, Eastern Europe, Anatolia, etc. Past and future climate change has an impact on the operating conditions of ski resorts, due to their reliance on natural snowfall and favorable conditions for snowmaking. However, there is currently a lack of assessment of past and future operating conditions of ski resorts at the pan-European scale in the context of climate change. The presented work aims at filling this gap, as part of the "European Tourism" Sectoral Information System (SIS) of the Copernicus Climate Change Services (C3S). The Mountain Tourism Meteorological and Snow Indicators (MTMSI) were co-designed with representatives of the ski tourism industry, including consulting companies. They were derived from statistically adjusted EURO-CORDEX climate projections (multiple GCM/RCM pairs for RCP2.6, RCP4.5 and RCP8.5) using the UERRA 5.5 km resolution surface reanalysis as a reference, used as input to the snow cover model Crocus, with and without accounting for snow management (grooming, snowmaking). Results are generated for 100 m elevation bands for NUTS-3 geographical areas spanning all areas relevant to ski tourism in Europe. This article introduces the underpinning elements for the generation of this product, and illustrates results at the pan-European scale as well as for smaller scale case studies. A dedicated visualization app allows for easy navigation into the multiple dimensions of this dataset, thereby fulfilling the needs of a broad range of users.

7.
Nat Immunol ; 22(4): 471-484, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664518

RESUMO

The diversity of regulatory T (Treg) cells in health and in disease remains unclear. Individuals with colorectal cancer harbor a subpopulation of RORγt+ Treg cells with elevated expression of ß-catenin and pro-inflammatory properties. Here we show progressive expansion of RORγt+ Treg cells in individuals with inflammatory bowel disease during inflammation and early dysplasia. Activating Wnt-ß-catenin signaling in human and murine Treg cells was sufficient to recapitulate the disease-associated increase in the frequency of RORγt+ Treg cells coexpressing multiple pro-inflammatory cytokines. Binding of the ß-catenin interacting partner, TCF-1, to DNA overlapped with Foxp3 binding at enhancer sites of pro-inflammatory pathway genes. Sustained Wnt-ß-catenin activation induced newly accessible chromatin sites in these genes and upregulated their expression. These findings indicate that TCF-1 and Foxp3 together limit the expression of pro-inflammatory genes in Treg cells. Activation of ß-catenin signaling interferes with this function and promotes the disease-associated RORγt+ Treg phenotype.


Assuntos
Proliferação de Células , Reprogramação Celular , Colite Ulcerativa/metabolismo , Neoplasias Associadas a Colite/metabolismo , Doença de Crohn/metabolismo , Epigênese Genética , Ativação Linfocitária , Linfócitos T Reguladores/metabolismo , Via de Sinalização Wnt , Animais , Estudos de Casos e Controles , Células Cultivadas , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Neoplasias Associadas a Colite/genética , Neoplasias Associadas a Colite/imunologia , Doença de Crohn/genética , Doença de Crohn/imunologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fenótipo , Fator 1 de Transcrição de Linfócitos T , Linfócitos T Reguladores/imunologia
8.
Int J Biometeorol ; 65(5): 659-675, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32462226

RESUMO

This study investigates the relationship between snow conditions and snowmaking investments for over 100 French Alps ski resorts. Investment trends represent a critical issue in capital-intensive sectors such as the ski industry. The data are based on snow reliability indicators and snowmaking investments covering 1997-2014. Descriptive statistics reveal that snowmaking has been the second investment item for ski resorts regardless of the elevation or ski resort size. The study finds that snowmaking investments are highly negatively correlated to snow conditions of the prior year for small and medium-sized ski resorts. Other factors are also likely to play a significant role in driving snowmaking investment dynamics.


Assuntos
Esqui , Neve , Indústrias , Reprodutibilidade dos Testes
9.
Proc Natl Acad Sci U S A ; 110(44): 17668-73, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23431201

RESUMO

Long-term observations of the reactive chemical composition of the tropical marine boundary layer (MBL) are rare, despite its crucial role for the chemical stability of the atmosphere. Recent observations of reactive bromine species in the tropical MBL showed unexpectedly high levels that could potentially have an impact on the ozone budget. Uncertainties in the ozone budget are amplified by our poor understanding of the fate of NOx (= NO + NO2), particularly the importance of nighttime chemical NOx sinks. Here, we present year-round observations of the multiisotopic composition of atmospheric nitrate in the tropical MBL at the Cape Verde Atmospheric Observatory. We show that the observed oxygen isotope ratios of nitrate are compatible with nitrate formation chemistry, which includes the BrNO3 sink at a level of ca. 20 ± 10% of nitrate formation pathways. The results also suggest that the N2O5 pathway is a negligible NOx sink in this environment. Observations further indicate a possible link between the NO2/NOx ratio and the nitrogen isotopic content of nitrate in this low NOx environment, possibly reflecting the seasonal change in the photochemical equilibrium among NOx species. This study demonstrates the relevance of using the stable isotopes of oxygen and nitrogen of atmospheric nitrate in association with concentration measurements to identify and constrain chemical processes occurring in the MBL.


Assuntos
Atmosfera/análise , Modelos Químicos , Nitratos/análise , Cabo Verde , Cromatografia por Troca Iônica , Estações do Ano , Clima Tropical
10.
Science ; 322(5902): 730-2, 2008 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-18974350

RESUMO

Atmospheric nitrogen oxides (NOx =NO+ NO2) play a pivotal role in the cycling of reactive nitrogen (ultimately deposited as nitrate) and the oxidative capacity of the atmosphere. Combined measurements of nitrogen and oxygen stable isotope ratios of nitrate collected in the Arctic atmosphere were used to infer the origin and fate of NOx and nitrate on a seasonal basis. In spring, photochemically driven emissions of reactive nitrogen from the snowpack into the atmosphere make local oxidation of NOx by bromine oxide the major contributor to the nitrate budget. The comprehensive isotopic composition of nitrate provides strong constraints on the relative importance of the key atmospheric oxidants in the present atmosphere, with the potential for extension into the past using ice cores.

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