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Oxysterols (i.e., oxidized cholesterol species) have complex roles in biology. 25-hydroxycholesterol (25HC), a product of activity of cholesterol-25-hydroxylase (CH25H) upon cholesterol, has recently been shown to be broadly antiviral, suggesting therapeutic potential against SARS-CoV-2. However, 25HC can also amplify inflammation and tissue injury and be converted by CYP7B1 to 7α,25HC, a lipid with chemoattractant activity via the G protein-coupled receptor, EBI2/GPR183. Here, using in vitro studies and two different murine models of SARS-CoV-2 infection, we investigate the effects of these two oxysterols on SARS-CoV-2 pneumonia. We show that while 25HC and enantiomeric-25HC are antiviral in vitro against human endemic coronavirus-229E, they did not inhibit SARS-CoV-2; nor did supplemental 25HC reduce pulmonary SARS-CoV-2 titers in the K18-human ACE2 mouse model in vivo. 25HC treatment also did not alter immune cell influx into the airway, airspace cytokines, lung pathology, weight loss, symptoms, or survival but was associated with increased airspace albumin, an indicator of microvascular injury, and increased plasma pro-inflammatory cytokines. Conversely, mice treated with the EBI2/GPR183 inhibitor NIBR189 displayed a modest increase in lung viral load only at late time points, but no change in weight loss. Consistent with these findings, although Ch25h was upregulated in the lungs of SARS-CoV-2-infected WT mice, lung viral titers and weight loss in Ch25h-/- and Gpr183-/- mice infected with the beta variant were similar to control animals. Taken together, endogenous 25-hydroxycholesterols do not significantly regulate early SARS-CoV-2 replication or pathogenesis and supplemental 25HC may have pro-injury rather than therapeutic effects in SARS-CoV-2 pneumonia.
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During 2019, an infrared camera, the compact thermal imager (CTI), recorded 15 million images of the Earth from the International Space Station. CTI is based on strained-layer superlattice (SLS) detector technology. The camera covered the spectral range from 3 to 11 µm in two spectral channels, 3.3-5.4 and 7.8-10.7 µm. Individual image frames were 26×21km2 projected on the ground, with 82 m pixel resolution. A frame time of 2.54 s created continuous image swaths with a 13% along-track image overlap. Upper limits determined on the ground and in flight for the electronic offset, read noise, and dark current demonstrated the stability of the SLS detector and camera over many months. Temperature calibration was established using a combination of preflight and in-flight measurements. A narrowband approximation of temperature as a function of photon counts produced an analytic relationship covering a temperature range of 0°-400°C. Examples of CTI images illustrate temperature retrievals over sea ice, urban and agricultural areas, desert, and wildfires.
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In situ probes are being developed to make direct, spatially resolved measurements of the ion energy spectra in the edge of tokamak plasmas while being easily replaced and requiring minimal resources. The ion spectrometers will consist of a combined collimator and energy analyzer fabricated from silicon and mated to a detector to yield a form factor of approximately 2.0 cm × 1.5 cm × 0.2 cm. Results of fabrication and testing of the combined collimator and energy analyzer element are presented.
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Charcoal production for urban energy consumption is a main driver of forest degradation in sub Saharan Africa. Urban growth projections for the continent suggest that the relevance of this process will increase in the coming decades. Forest degradation associated to charcoal production is difficult to monitor and commonly overlooked and underrepresented in forest cover change and carbon emission estimates. We use a multitemporal dataset of very high-resolution remote sensing images to map kiln locations in a representative study area of tropical woodlands in central Mozambique. The resulting maps provided a characterization of the spatial extent and temporal dynamics of charcoal production. Using an indirect approach we combine kiln maps and field information on charcoal making to describe the magnitude and intensity of forest degradation linked to charcoal production, including aboveground biomass and carbon emissions. Our findings reveal that forest degradation associated to charcoal production in the study area is largely independent from deforestation driven by agricultural expansion and that its impact on forest cover change is in the same order of magnitude as deforestation. Our work illustrates the feasibility of using estimates of urban charcoal consumption to establish a link between urban energy demands and forest degradation. This kind of approach has potential to reduce uncertainties in forest cover change and carbon emission assessments in sub-Saharan Africa.
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Cationic cellulosic polymers find wide utility as benefit agents in shampoo. Deposition of these polymers onto hair has been shown to mend split-ends, improve appearance and wet combing, as well as provide controlled delivery of insoluble actives. The deposition is thought to be enhanced by the formation of a polymer/surfactant complex that phase-separates from the bulk solution upon dilution. A standard characterization method has been developed to characterize the coacervate formation upon dilution, but the test is time and material prohibitive. We have developed a semi-automated high throughput workflow to characterize the coacervate-forming behavior of different shampoo formulations. A procedure that allows testing of real use shampoo dilutions without first formulating a complete shampoo was identified. This procedure was adapted to a Tecan liquid handler by optimizing the parameters for liquid dispensing as well as for mixing. The high throughput workflow enabled preparation and testing of hundreds of formulations with different types and levels of cationic cellulosic polymers and surfactants, and for each formulation a haze diagram was constructed. Optimal formulations and their dilutions that give substantial coacervate formation (determined by haze measurements) were identified. Results from this high throughput workflow were shown to reproduce standard haze and bench-top turbidity measurements, and this workflow has the advantages of using less material and allowing more variables to be tested with significant time savings.
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Celulose/química , Preparações para Cabelo/química , Polímeros/química , Tensoativos/química , Micelas , Nefelometria e TurbidimetriaRESUMO
Despite a century of confidence and optimism in modern medicine and technology inspired by their often successful prevention and control efforts, infectious diseases remain an omnipresent, conspicuous major challenge to public health. Effective detection and control of infectious diseases require predictive and proactive efficient methods that provide early warning of an epidemic activity. Of particular relevance to these efforts is linking information at the landscape and coarser scales to data at the scale of the epidemic activity. In recent years, landscape epidemiology has used satellite remote sensing and geographic information systems as the technology capable of providing, from local to global scales, spatial and temporal climatic patterns that may influence the intensity of a vector-borne disease and predicts risk conditions associated with an epidemic. This article provides a condensed, and selective look at classical material and recent research about remote sensing and GIS (geographic information system) applications in public health.
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Clima , Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Emergentes/prevenção & controle , Monitoramento Ambiental/métodos , Vigilância da População , África Central/epidemiologia , Animais , Doenças dos Símios Antropoides/epidemiologia , Controle de Doenças Transmissíveis/instrumentação , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Surtos de Doenças , Reservatórios de Doenças , Vetores de Doenças , Monitoramento Ambiental/instrumentação , Monitoramento Epidemiológico , Previsões , Sistemas de Informação Geográfica , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/veterinária , Humanos , Modelos Teóricos , Pan troglodytes/virologia , Estações do Ano , Astronave , Topografia Médica , Clima TropicalRESUMO
An increase in photosynthetic activity of the northern hemisphere terrestrial vegetation, as derived from satellite observations, has been reported in previous studies. The amplitude of the seasonal cycle of the annually detrended atmospheric CO(2) in the northern hemisphere (an indicator of biospheric activity) also increased during that period. We found, by analyzing the annually detrended CO(2) record by season, that early summer (June) CO(2) concentrations indeed decreased from 1985 to 1991, and they have continued to decrease from 1994 up to 2002. This decrease indicates accelerating springtime net CO(2) uptake. However, the CO(2) minimum concentration in late summer (an indicator of net growing-season uptake) showed no positive trend since 1994, indicating that lower net CO(2) uptake during summer cancelled out the enhanced uptake during spring. Using a recent satellite normalized difference vegetation index data set and climate data, we show that this lower summer uptake is probably the result of hotter and drier summers in both mid and high latitudes, demonstrating that a warming climate does not necessarily lead to higher CO(2) growing-season uptake, even in high-latitude ecosystems that are considered to be temperature limited.
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Dióxido de Carbono/metabolismo , Clima , Plantas/metabolismo , Efeito Estufa , Fotossíntese , Chuva , Estações do Ano , TemperaturaRESUMO
The use of DNA microarrays has spanned numerous disciplines of life science research. Despite the volume of studies utilizing this technology, no consensus exists on basic issues such as the determination of significantly altered genes in a given experiment, often leading to either false-negative or false-positive data. In this report, we study the effect of dilution of biological alterations on the detection level of gene expression differences using cDNA microarrays. We propose that subtle alterations in transcript levels of genes below the 2-fold level should be considered when replicate hybridizations are performed, because these subtle gene expression changes may be due to a robust response in few cells. We measured the effect of dilution of gene expression and found that differences in gene expression between the two cell lines assayed (HaCaT and MCF-7) were detected even after a 20-fold dilution factor. These results better our understanding of biological alterations that comprise a relatively small percentage of an assayed organ and help in the interpretation of gene expression data.
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Perfilação da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Linhagem Celular , DNA Complementar , Humanos , Sensibilidade e EspecificidadeRESUMO
The terrestrial carbon sink, as of yet unidentified, represents 15-30% of annual global emissions of carbon from fossil fuels and industrial activities. Some of the missing carbon is sequestered in vegetation biomass and, under the Kyoto Protocol of the United Nations Framework Convention on Climate Change, industrialized nations can use certain forest biomass sinks to meet their greenhouse gas emissions reduction commitments. Therefore, we analyzed 19 years of data from remote-sensing spacecraft and forest inventories to identify the size and location of such sinks. The results, which cover the years 1981-1999, reveal a picture of biomass carbon gains in Eurasian boreal and North American temperate forests and losses in some Canadian boreal forests. For the 1.42 billion hectares of Northern forests, roughly above the 30th parallel, we estimate the biomass sink to be 0.68 +/- 0.34 billion tons carbon per year, of which nearly 70% is in Eurasia, in proportion to its forest area and in disproportion to its biomass carbon pool. The relatively high spatial resolution of these estimates permits direct validation with ground data and contributes to a monitoring program of forest biomass sinks under the Kyoto protocol.
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Biomassa , Carbono/metabolismo , Árvores/metabolismo , MadeiraRESUMO
This study examined the nature and extent of adolescent siblings' supportive roles and the conditions under which siblings provide support to one another about familial and nonfamilial issues. Data were collected from 185 adolescent firstborn (M age = 16 years) and second born (M age = 13 years) sibling pairs. In home interviews, siblings reported on family experiences and psychosocial functioning during the past year. In a series of 7 evening telephone interviews, siblings reported on their shared daily activities. Findings suggested that both older and younger siblings view older siblings as sources of support about nonfamilial issues such as social and scholastic activities and that siblings assume equally supportive roles about familial issues. Further, the results suggested that family background characteristics, sibling relationship qualities, and adolescents' psychosocial functioning were linked to the nature and extent of sibling support.
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Relações Interpessoais , Relações entre Irmãos , Apoio Social , Adolescente , HumanosRESUMO
All known Rift Valley fever(RVF) outbreaks in Kenya from 1950 to 1998 followed periods of abnormally high rainfall. On an interannual scale, periods of above normal rainfall in East Africa are associated with the warm phase of the El Niño/Southern Oscillation (ENSO) phenomenon. Anomalous rainfall floods mosquito-breeding habitats called dambos, which contain transovarially infected mosquito eggs. The eggs hatch Aedes mosquitoes that transmit the RVF virus preferentially to livestock and to humans as well. Analysis of historical data on RVF outbreaks and indicators of ENSO (including Pacific and Indian Ocean sea surface temperatures and the Southern Oscillation Index) indicates that more than three quarters of the RVF outbreaks have occurred during warm ENSO event periods. Mapping of ecological conditions using satellite normalized difference vegetation index (NDVI) data show that areas where outbreaks have occurred during the satellite recording period (1981-1998) show anomalous positive departures in vegetation greenness, an indicator of above-normal precipitation. This is particularly observed in arid areas of East Africa, which are predominantly impacted by this disease. These results indicate a close association between interannual climate variability and RVF outbreaks in Kenya.
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Clima , Surtos de Doenças , Febre do Vale de Rift/epidemiologia , Aedes , Animais , Bovinos , Reservatórios de Doenças , Humanos , Insetos Vetores , Quênia/epidemiologia , Chuva , Febre do Vale de Rift/transmissão , Ovinos , TemperaturaRESUMO
The Sea-viewing Wide Field-of-view Sensor (SeaWiFS) provides global monthly measurements of both oceanic phytoplankton chlorophyll biomass and light harvesting by land plants. These measurements allowed the comparison of simultaneous ocean and land net primary production (NPP) responses to a major El Niño to La Niña transition. Between September 1997 and August 2000, biospheric NPP varied by 6 petagrams of carbon per year (from 111 to 117 petagrams of carbon per year). Increases in ocean NPP were pronounced in tropical regions where El Niño-Southern Oscillation (ENSO) impacts on upwelling and nutrient availability were greatest. Globally, land NPP did not exhibit a clear ENSO response, although regional changes were substantial.
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Biomassa , Clorofila/análise , Clima , Fotossíntese , Fitoplâncton/metabolismo , Plantas/metabolismo , Luz , Oceanos e Mares , Fitoplâncton/crescimento & desenvolvimento , Desenvolvimento Vegetal , Estações do Ano , Água do Mar , AstronaveRESUMO
Normalized difference vegetation index data from the polar-orbiting National Oceanic and Atmospheric Administration meteorological satellites from 1982 to 1999 show significant variations in photosynthetic activity and growing season length at latitudes above 35 degrees N. Two distinct periods of increasing plant growth are apparent: 1982-1991 and 1992-1999, separated by a reduction from 1991 to 1992 associated with global cooling resulting from the volcanic eruption of Mt. Pinatubo in June 1991. The average May to September normalized difference vegetation index from 45 degrees N to 75 degrees N increased by 9% from 1982 to 1991, decreased by 5% from 1991 to 1992, and increased by 8% from 1992 to 1999. Variations in the normalized difference vegetation index were associated with variations in the start of the growing season of -5.6, +3.9, and -1.7 days respectively, for the three time periods. Our results support surface temperature increases within the same period at higher northern latitudes where temperature limits plant growth.
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Ecossistema , Fotossíntese , Plantas , Clima , Monitoramento Ambiental , Estações do Ano , Astronave , Temperatura , Fatores de TempoRESUMO
This study assessed links between free-time activities in middle childhood (hobbies, sports, toys and games, outdoor play, reading, television viewing, and hanging out) and school grades, conduct, and depression symptoms both concurrently and 2 years later, in early adolescence. It also explored two mechanisms that might underlie activity-adjustment links: whether the social contexts of children's activities mediate these links, child effects explain these connections, or both. Participants were 198 children (M = 10.9 years, SD = .54 years) in Year 1, and their parents. In home interviews in Years 1 and 3 of the study, mothers rated children's conduct problems, children reported on their depression symptoms, and information was collected on school grades from report cards. In seven evening phone interviews, children reported on the time they spent in free-time activities during the day of the call and their companions in each activity. Links were found between the nature of children's free-time activities and their adjustment. The social contexts of free-time activities explained activity-adjustment links to a limited degree; with respect to child effects, evidence also suggested that better adjusted children became more involved in adaptive activities over time.
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Atividades de Lazer , Ajustamento Social , Adolescente , Comportamento do Adolescente/psicologia , Criança , Feminino , Seguimentos , Humanos , Masculino , Pais , Fatores SocioeconômicosRESUMO
The relationships between adolescents' explanations for unemployment, poverty, and homelessness and their beliefs about opportunity, reports of family values, and personal aspirations were tested for 434 teenagers (mean age = 16 years 4 months). Explanations were coded for references to individual causes, societal causes, or both. Higher maternal education and average household income in the adolescent's school district were positively related to the likelihood of attributing all three problems to societal causes. When explaining unemployment, older adolescents noted both causes, and boys mentioned individual factors whereas girls mentioned societal factors. After adjustment for background factors, those endorsing individual causes were more likely to believe that all Americans enjoyed equal opportunity and that government support encouraged dependency, and they were more committed to materialist goals. In contrast, youth endorsing societal or situational causes had more altruistic life goals and reported that compassion was emphasized in their families.
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Comportamento do Adolescente/psicologia , Atitude , Política , Autoimagem , Percepção Social , Adolescente , Família/psicologia , Feminino , Humanos , Masculino , Psicologia do Adolescente , Inquéritos e QuestionáriosRESUMO
We studied the extent of sex-typing across different areas of child functioning (personality, interests, activities) in middle childhood as a function of the traditionality of parents' gender role attitudes and the sex composition of the sibling dyad. Participants included 200 firstborn children (mean = 10.4 years old), their secondborn siblings (mean = 7.7 years old) and their mothers and fathers. Family members were interviewed in their homes about their attitudes and personal characteristics and completed a series of seven evening telephone interviews about their daily activities. We measured children's attitudes, personality characteristics, and interests in sex-typed leisure activities (e.g., sports, handicrafts) as well as time spent in sex-typed leisure activities and household tasks (e.g., washing dishes, home repairs) and with same and opposite sex companions (i.e., parents, peers). Analyses revealed that sex-typing was most evident in children's interests and activities. Further, comparisons of girls versus boys and sisters versus brothers revealed that differences in children's sex-typing as a function of fathers' attitudes and sibling sex constellation were most apparent for children's activities. A notable exception was sex-typed peer involvement; time spent with same versus opposite sex peers was impervious to context effects. Analyses focused on children's sex-typing as a function of mothers' attitudes generally were nonsignificant.
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Família/psicologia , Identidade de Gênero , Relações entre Irmãos , Socialização , Criança , Comportamento Infantil/psicologia , Feminino , Seguimentos , Humanos , Masculino , Relações Pais-Filho , Pais/psicologia , Determinação da Personalidade , Psicologia da CriançaRESUMO
All known Rift Valley fever virus outbreaks in East Africa from 1950 to May 1998, and probably earlier, followed periods of abnormally high rainfall. Analysis of this record and Pacific and Indian Ocean sea surface temperature anomalies, coupled with satellite normalized difference vegetation index data, shows that prediction of Rift Valley fever outbreaks may be made up to 5 months in advance of outbreaks in East Africa. Concurrent near-real-time monitoring with satellite normalized difference vegetation data may identify actual affected areas.
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Clima , Surtos de Doenças , Previsões , Febre do Vale de Rift/epidemiologia , Tempo (Meteorologia) , Animais , Humanos , Quênia/epidemiologia , Oceanos e Mares , Oceano Pacífico , Chuva , Febre do Vale de Rift/prevenção & controle , Febre do Vale de Rift/veterinária , TemperaturaRESUMO
Sandfly fever and leishmaniasis were major causes of infectious disease morbidity among military personnel deployed to the Middle East during World War II. Recently, leishmaniasis has been reported in the United Nations Multinational Forces and Observers in the Sinai. Despite these indications of endemicity, no cases of sandfly fever and only 31 cases of leishmaniasis have been identified among U.S. veterans of the Persian Gulf War. The distribution in the Persian Gulf of the vector, Phlebotomus papatasi, is thought to be highly dependent on environmental conditions, especially temperature and relative humidity. A computer model was developed using the occurrence of P. papatasi as the dependent variable and weather data as the independent variables. The results of this model indicated that the greatest sand fly activity and thus the highest risk of sandfly fever and leishmania infections occurred during the spring/summer months before U.S. troops were deployed to the Persian Gulf. Because the weather model produced probability of occurrence information for locations of the weather stations only, normalized difference vegetation index (NDVI) levels from remotely sensed Advanced Very High Resolution Radiometer satellites were determined for each weather station. From the results of the frequency of NDVI levels by probability of occurrence, the range of NDVI levels for presence of the vector was determined. The computer then identified all pixels within the NDVI range indicated and produced a computer-generated map of the probable distribution of P. papatasi. The resulting map expanded the analysis to areas where there were no weather stations and from which no information was reported in the literature, identifying these areas as having either a high or low probability of vector occurrence.