522 research outputs found
The water cycle and regolith-atmosphere interaction at Gale crater, Mars
We perform mesoscale simulations of the water cycle in a region around Gale crater, including the diffusion of water vapour in and out of the regolith, and compare our results with measurements from the REMS instrument on board the Curiosity rover. Simulations are performed at three times of year, and show that diffusion in and out of the regolith and adsorption/desorption needs to be taken into account in order to match the diurnal variation of relative humidity measured by REMS. During the evening and night, local downslope flows transport water vapour down the walls of Gale crater. When including regolith-atmosphere interaction, the amount of vapour reaching the crater floor is reduced (by factors of 2–3 depending on season) due to vapour diffusing into the regolith along the crater walls. The transport of vapour into Gale crater is also affected by the regional katabatic flow over the dichotomy boundary, with the largest flux of vapour into the regolith initially occurring on the northern crater wall, and moving to the southern wall by early morning. Upslope winds during the day transport vapour desorbing and mixing out of the regolith up crater walls, where it can then be transported a few hundred metres into the atmosphere at convergence boundaries. Regolith-atmosphere interaction limits the formation of surface ice by reducing water vapour abundances in the lower atmosphere, though in some seasons ice can still form in the early morning on eastern crater walls. Subsurface ice amounts are small in all seasons, with ice only existing in the upper few millimetres of regolith during the night. The results at Gale crater are representative of the behaviour at other craters in the mesoscale domain
Supervised oral HIV self-testing is accurate in rural KwaZulu Natal, South Africa
Objectives: To achieve UNAIDS 90-90-90 targets, alternatives to conventional HIV testing models are necessary in South Africa to increase population awareness of their HIV status. One of the alternatives is oral mucosal transudates-based HIV self-testing (OralST). This study describes implementation of counsellor-introduced supervised OralST in a high HIV prevalent rural area. Methods: Cross-sectional study conducted in two government-run primary healthcare clinics and three Médecins Sans Frontières-run fixed-testing sites in uMlalazi municipality, KwaZulu-Natal. Lay counsellors sampled and recruited eligible participants, sought informed consent and demonstrated the use of the OraQuick(™) OralST. The participants used the OraQuick(™) in front of the counsellor and underwent a blood-based Determine(™) and a Unigold(™) rapid diagnostic test as gold standard for comparison. Primary outcomes were user error rates, inter-rater agreement, sensitivity, specificity and predictive values. Results: A total of 2198 participants used the OraQuick(™) , of which 1005 were recruited at the primary healthcare clinics. Of the total, 1457 (66.3%) were women. Only two participants had to repeat their OraQuick(™) . Inter-rater agreement was 99.8% (Kappa 0.9925). Sensitivity for the OralST was 98.7% (95% CI 96.8-99.6), and specificity was 100% (95% CI 99.8-100). Conclusion: This study demonstrates high inter-rater agreement, and high accuracy of supervised OralST. OralST has the potential to increase uptake of HIV testing and could be offered at clinics and community testing sites in rural South Africa. Further research is necessary on the potential of unsupervised OralST to increase HIV status awareness and linkage to care
Mudanças no peso corporal na coorte NutriNet Brasil durante a pandemia de covid-19
Este estudo descreve modificações no peso corporal de participantes da coorte NutriNet Brasil (n = 14.259) ocorridas durante a pandemia de covid-19. Foram analisados dados informados em perÃodo anterior ao inÃcio da pandemia (26/01/2020 a 18/03/2020) e cerca de 6 meses após (14/09/2020 a 19/10/2020). O ganho de peso ≥ 2 kg alcançou 19,7% dos participantes, mostrando-se diretamente associado ao sexo masculino, à menor escolaridade e à presença prévia de excesso de peso, sendo inversamente associado à idade. A perda de peso ≥ 2kg alcançou 15,2% dos participantes, mostrando-se diretamente associada ao sexo masculino e à presença prévia de excesso de peso, sendo inversamente associada à idade.This study describes body weight changes among participants of the NutriNet Brasil cohort(n = 14,259) during the covid-19 pandemic. We analyzed data reported before the pandemic onset(01/26/2020 to 03/18/2020) and about six months after (09/14/2020 to 10/19/2020). Our resultsshow that 19.7% of the participants gained ≥ 2 kg. Weight gain was directly associated withmale gender, lower education, and previous presence of overweight, and inversely associatedwith age. In turn, 15.2% lost ≥ 2kg, being directly associated with male gender and previouspresence of overweight and inversely associated with age
The share of ultra-processed foods and the overall nutritional quality of diets in the US: evidence from a nationally representative cross-sectional study
Abstract Background Recent population dietary studies indicate that diets rich in ultra-processed foods, increasingly frequent worldwide, are grossly nutritionally unbalanced, suggesting that the dietary contribution of these foods largely determines the overall nutritional quality of contemporaneous diets. Yet, these studies have focused on individual nutrients (one at a time) rather than the overall nutritional quality of the diets. Here we investigate the relationship between the energy contribution of ultra-processed foods in the US diet and its content of critical nutrients, individually and overall. Methods We evaluated dietary intakes of 9,317 participants from 2009 to 2010 NHANES aged 1+ years. Food items were classified into unprocessed or minimally processed foods, processed culinary ingredients, processed foods, and ultra-processed foods. First, we examined the average dietary content of macronutrients, micronutrients, and fiber across quintiles of the energy contribution of ultra-processed foods. Then, we used Principal Component Analysis (PCA) to identify a nutrient-balanced dietary pattern to enable the assessment of the overall nutritional quality of the diet. Linear regression was used to explore the association between the dietary share of ultra-processed foods and the balanced-pattern PCA factor score. The scores were thereafter categorized into tertiles, and their distribution was examined across ultra-processed food quintiles. All models incorporated survey sample weights and were adjusted for age, sex, race/ethnicity, family income, and educational attainment. Results The average content of protein, fiber, vitamins A, C, D, and E, zinc, potassium, phosphorus, magnesium, and calcium in the US diet decreased significantly across quintiles of the energy contribution of ultra-processed foods, while carbohydrate, added sugar, and saturated fat contents increased. An inverse dose–response association was found between ultra-processed food quintiles and overall dietary quality measured through a nutrient-balanced-pattern PCA-derived factor score characterized by being richer in fiber, potassium, magnesium and vitamin C, and having less saturated fat and added sugars. Conclusions This study suggests that decreasing the dietary share of ultra-processed foods is a rational and effective way to improve the nutritional quality of US diets
The share of ultra-processed foods and the overall nutritional quality of diets in the US: evidence from a nationally representative cross-sectional study
BACKGROUND: Recent population dietary studies indicate that diets rich in ultra-processed foods, increasingly frequent worldwide, are grossly nutritionally unbalanced, suggesting that the dietary contribution of these foods largely determines the overall nutritional quality of contemporaneous diets. Yet, these studies have focused on individual nutrients (one at a time) rather than the overall nutritional quality of the diets. Here we investigate the relationship between the energy contribution of ultra-processed foods in the US diet and its content of critical nutrients, individually and overall. METHODS: We evaluated dietary intakes of 9,317 participants from 2009 to 2010 NHANES aged 1+ years. Food items were classified into unprocessed or minimally processed foods, processed culinary ingredients, processed foods, and ultra-processed foods. First, we examined the average dietary content of macronutrients, micronutrients, and fiber across quintiles of the energy contribution of ultra-processed foods. Then, we used Principal Component Analysis (PCA) to identify a nutrient-balanced dietary pattern to enable the assessment of the overall nutritional quality of the diet. Linear regression was used to explore the association between the dietary share of ultra-processed foods and the balanced-pattern PCA factor score. The scores were thereafter categorized into tertiles, and their distribution was examined across ultra-processed food quintiles. All models incorporated survey sample weights and were adjusted for age, sex, race/ethnicity, family income, and educational attainment. RESULTS: The average content of protein, fiber, vitamins A, C, D, and E, zinc, potassium, phosphorus, magnesium, and calcium in the US diet decreased significantly across quintiles of the energy contribution of ultra-processed foods, while carbohydrate, added sugar, and saturated fat contents increased. An inverse dose-response association was found between ultra-processed food quintiles and overall dietary quality measured through a nutrient-balanced-pattern PCA-derived factor score characterized by being richer in fiber, potassium, magnesium and vitamin C, and having less saturated fat and added sugars. CONCLUSIONS: This study suggests that decreasing the dietary share of ultra-processed foods is a rational and effective way to improve the nutritional quality of US diets
Expansion of a single transposable element family is associated with genome-size increase and radiation in the genus Hydra
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.Transposable elements are one of the major contributors to genome-size differences in metazoans. Despite this, relatively little is known about the evolutionary patterns of element expansions and the element families involved. Here we report a broad genomic sampling within the genus Hydra, a freshwater cnidarian at the focal point of diverse research in regeneration, symbiosis, biogeography, and aging. We find that the genome of Hydra is the result of an expansion event involving long interspersed nuclear elements and in particular a single family of the chicken repeat 1 (CR1) class. This expansion is unique to a subgroup of the genus Hydra, the brown hydras, and is absent in the green hydra, which has a repeat landscape similar to that of other cnidarians. These features of the genome make Hydra attractive for studies of transposon-driven genome expansions and speciation
Estimating Global Ecosystem Isohydry/Anisohydry Using Active and Passive Microwave Satellite Data
The concept of isohydry/anisohydry describes the degree to which plants regulate their water status, operating from isohydric with strict regulation to anisohydric with less regulation. Though some species level measures of isohydry/anisohydry exist at a few locations, ecosystem-scale information is still largely unavailable. In this study, we use diurnal observations from active (Ku-Band backscatter from QuikSCAT) and passive (X-band vegetation optical depth (VOD) from Advanced Microwave Scanning Radiometer on EOS Aqua) microwave satellite data to estimate global ecosystem isohydry/anisohydry. Here diurnal observations from both satellites approximate predawn and midday plant canopy water contents, which are used to estimate isohydry/anisohydry. The two independent estimates from radar backscatter and VOD show reasonable agreement at low and middle latitudes but diverge at high latitudes. Grasslands, croplands, wetlands, and open shrublands are more anisohydric, whereas evergreen broadleaf and deciduous broadleaf forests are more isohydric. The direct validation with upscaled in situ species isohydry/anisohydry estimates indicates that the VOD-based estimates have much better agreement than the backscatter-based estimates. The indirect validation with prior knowledge suggests that both estimates are generally consistent in that vegetation water status of anisohydric ecosystems more closely tracks environmental fluctuations of water availability and demand than their isohydric counterparts. However, uncertainties still exist in the isohydry/anisohydry estimate, primarily arising from the remote sensing data and, to a lesser extent, from the methodology. The comprehensive assessment in this study can help us better understand the robustness, limitation, and uncertainties of the satellite-derived isohydry/anisohydry estimates. The ecosystem isohydry/anisohydry has the potential to reveal new insights into spatiotemporal ecosystem response to droughts
SrMo0.9Co0.1O3−δ: A potential anode for intermediate-temperature solid-oxide fuel cells (IT-SOFC)
Nova score for the consumption of ultra-processed foods: description and performance evaluation in Brazil
OBJETIVO Descrever o escore Nova de consumo de alimentos ultraprocessados e avaliar seu potencial para refletir, no contexto brasileiro, a participação desses alimentos na dieta. MÉTODOS Estudo realizado na cidade de São Paulo com amostra de conveniência de 300 adultos, que responderam, em cerca de três minutos, em um tablet, a um questionário eletrônico de autorrelato sobre o consumo, no dia anterior, de 23 subgrupos de alimentos ultraprocessados comumente consumidos no Brasil. O escore de cada participante correspondeu ao número de subgrupos reportados. A participação de alimentos ultraprocessados no consumo alimentar do mesmo dia, expressa como percentual da ingestão total de energia, foi calculada por meio das respostas dos participantes a recordatório alimentar completo de 24 horas aplicado em cerca de 30 minutos por nutricionistas treinados. A associação entre o escore e a participação de ultraprocessados na dieta foi estudada por modelos de regressão linear. A concordância na classificação dos participantes segundo quintos do escore e quintos da participação de alimentos ultraprocessados na dieta foi avaliada pelo Ãndice Pabak. RESULTADOS O percentual médio de participação de alimentos ultraprocessados na dieta aumentou linear e significativamente com o aumento do escore Nova de consumo de alimentos ultraprocessados. Observou-se concordância substancial na classificação dos participantes segundo quintos da distribuição do escore e quintos da distribuição do percentual de participação de alimentos ultraprocessados na dieta (Ãndice Pabak = 0,67). Relação inversa da idade com a frequência de consumo relativamente elevado de alimentos ultraprocessados (quinto superior da distribuição) foi observada tanto para o escore quanto para a participação de alimentos ultraprocessados na dieta. CONCLUSÃO O escore Nova de consumo de alimentos ultraprocessados, obtido de forma rápida e prática, apresenta bom potencial para refletir, no contexto brasileiro, a participação desses alimentos na dieta.OBJECTIVE: To describe the Nova score for the consumption of ultra-processed foods (UPF) and evaluate its potential in reflecting the dietary share of UPF in Brazil. METHODS: This study was conducted in São Paulo with a convenience sample of 300 adults. Using a tablet, participants answered a 3-minute electronic self-report questionnaire on the consumption of 23 subgroups of UPF commonly consumed in Brazil, regarding the day prior the survey. Each participant score corresponded to the number of subgroups reported. The dietary share of UPF on the day prior to the survey, expressed as a percentage of total energy intake, was calculated based on data collected on a 30-minute complete 24-hour dietary recall administered by trained nutritionists. The association between the score and the dietary share of UPF was evaluated using linear regression models. The Pabak index was used to assess the agreement in participants’ classification according to the fifths of Nova score and the fifths of dietary share of UPF. RESULTS: The average dietary share of UPF increased linearly and significantly with the increase of the Nova score for the consumption of ultra-processed foods. We found a substantial agreement in participants’ classification according to the fifths of the distribution of scores and the fifths of the dietary share of UPF (Pabak index = 0.67). Age was inversely associated with a relatively high frequency of UPF consumption (upper fifth of the distribution) for both score and dietary share of UPF. CONCLUSION: The Nova score for the consumption of ultra-processed foods, obtained in a quick and practical manner, shows a good potential in reflecting the dietary share of UPF in Brazi
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