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1.
J Contemp Dent Pract ; 21(6): 678-682, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33025938

RESUMO

AIMS: The purpose of this study was to assess the influence of hot and dry weather on the hardness and surface roughness of four different maxillofacial silicone elastomeric materials (MFSEM) including two room-temperature vulcanized (RTV) and two high-temperature vulcanized (HTV) materials. MATERIALS AND METHODS: Eighty test specimens were fabricated according to the manufacturer's instructions into rectangular test specimens. The hardness and surface roughness were tested, after 6 months of exposure to natural hot and dry weather. The hardness was measured through the International Rubber Hardness Degree (IRHD) scale using an automated hardness tester. The surface roughness was measured using a novel 3D optical noncontact technique using a combination of a light sectioning microscope and a computer vision system. Statistical Package for Social Sciences software SPSS/version 24 was used for analysis and a comparison between two independent variables was done using an independent t test, while more than two variables were analyzed, F test (ANOVA) to be used followed by a post hoc test to determine the level of significance between every two groups. RESULTS: The hot and dry weather statistically influenced the hardness and surface roughness of MFSEM. Cosmesil M-511 showed the least hardness in test groups while A-2000 showed the hardest material (p < 0.05). A-2000 showed significant changes from rough in case of nonweathered to become smoother in weather followed by A-2186 (p < 0.05). Cosmesil M-511 showed the roughest material. CONCLUSION: Cosmesil M-511 showed the least hard MFSEM after outdoor weathering while A-2000, the highest and least material showed hardness and surface roughness, respectively. CLINICAL IMPLICATION: A-2000 had a high IRHD scale hardness. This makes this material more suitable for the replacement of ear and nose defects. Cosmesil M-511 is soft and easily adaptable material that makes the material more appropriate for the replacement of small facial defect with undercut area to be easily inserted and removed. Whilst A-2000 is smoother and finer in test specimens after weathering, Cosmesil M-511 became rougher after weathering.


Assuntos
Prótese Maxilofacial , Dureza , Teste de Materiais , Propriedades de Superfície , Tempo (Meteorologia)
2.
Environ Monit Assess ; 192(11): 669, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33006646

RESUMO

We examined the spatial and temporal characteristics of tropical nights (TNs) in Seoul to determine whether land use factors increase the frequency of TN. The number of TN was derived using data from 23 Automatic Weathering Stations (AWS) in Seoul for 1998-2006, and 26 AWS in Seoul and nine Gangnam-gu stations for 2007-2013. The results show that the number of TN recorded in the Seoul Automatic Synoptic Observation System (ASOS) gradually increased from 1971 to 2013. TN occurred most frequently in early August, followed by mid-August, late July, late August, mid-July, early July, early September, and mid-September. The largest annual average difference occurred between Gangnam Station and Yeomgokdong, in spite of the short physical distance (4.5 km) between two stations at Gangnam-gu. There were more TNs at high-rise buildings and commercial business district (CBD) areas with low sky view factors (SVF) than in mountain foothill areas.


Assuntos
Monitoramento Ambiental , Tempo (Meteorologia) , Seul
3.
J Bras Pneumol ; 46(5): e20200183, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-33027470

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the highly contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is probably systemic, has a major respiratory component, and is transmitted by person-to-person contact, via airborne droplets or aerosols. In the respiratory tract, the virus begins to replicate within cells, after which the host starts shedding the virus. The individuals recognized as being at risk for an unfavorable COVID-19 outcome are those > 60 years of age, those with chronic diseases such as diabetes mellitus, those with hypertension, and those with chronic lung diseases, as well as those using chemotherapy, corticosteroids, or biological agents. Some studies have suggested that infection with SARS-CoV-2 is associated with other risk factors, such as smoking, external environmental pollution, and certain climatic conditions. The purpose of this narrative review was to perform a critical assessment of the relationship between COVID-19 and these potential risk factors.


Assuntos
Infecções por Coronavirus/epidemiologia , Poluição Ambiental/efeitos adversos , Pneumonia Viral/epidemiologia , Fumar/efeitos adversos , Tempo (Meteorologia) , Betacoronavirus , Humanos , Pandemias , Fatores de Risco
4.
Mar Pollut Bull ; 159: 111486, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32892920

RESUMO

Oil pollution resulting from natural and anthropogenic activities in the Arabian Gulf as well as oil residue in the form of tarmat (TM) deposited on the coast is a major environmental concern. The spatial distribution, chemical composition and weathering pattern of tarmat along the west coast of Qatar has been assessed based on the TM samples collected from 12 coastal regions. The range of TM distribution is 0-104 g m-1 with an average value of 9.25 g m-1. Though the current TM level is thirty-fold lesser than that was found during 1993-1997 (average 290 g m-1), the distribution pattern is similar. The results of ATR-FTIR spectroscopy indicate that aromatic compounds are higher in the north (N) coast TMs than those found in the northwest (NW) and southwest (SW) coasts, and Carbonyl Index values indicate that TM of NW coast is highly weathered compared to those found in the N and SW coasts.


Assuntos
Poluição por Petróleo/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Catar , Tempo (Meteorologia)
5.
Mar Environ Res ; 160: 105023, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907734

RESUMO

In the present study, using in-situ and satellite observations, we investigate the influence of physical processes on the enhancement of phytoplankton biomass in the eastern Arabian Sea (EAS). Water column measurements were carried out from 9°N to 21°N (stations II-2 to II-14) along 68°E transect in the EAS during the beginning of fall intermonsoon (FIM) of 2014. Both in-situ and satellite-derived chlorophyll a (Chl a) showed higher biomass at 15°N (station II-8) compared to northern and southern stations. We explored the possible physical processes which can lead to high biological productivity at this station. Our study shows that nearly two times enhancement in Chl a at station II-8 was contributed by an open-ocean front, which occurred two days before the measurement. Based on phytoplankton marker pigments, it was evident that haptophytes were abundant at II-8 with a minor contribution from diatoms and dinoflagellates. This condition also led to a high concentration (4.9 nM) of dimethylsulphide (DMS), an anti-green house gas with a net flux of 3.76 µmol m-2d-1 at this site. Among the picophytoplankton, Synechococcus were abundant at this station, however Prochlorococcus were absent as confirmed by both marker pigment and flow cytometric counts. The case study presented here demonstrates the dynamic nature of open ocean fronts and their overall contribution to the productivity of the eastern Arabian Sea during the oligotrophic inter-monsoon period.


Assuntos
Diatomáceas , Fitoplâncton , Biomassa , Clorofila A , Oceanos e Mares , Tempo (Meteorologia)
6.
Chemosphere ; 254: 126799, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957268

RESUMO

Enrichment of cadmium (Cd) during weathering and pedogenesis of carbonate rocks has resulted in large areas of lands with soil Cd concentrations exceeding the official guidelines in China and other countries. However, it is reported in many studies that the risk of soil contamination by Cd from this natural process can be neglected as most of the Cd is not bioavailable. Noticing that the previous studies focused only on eluvial areas but not on lowland alluvium, where Cd from the eluvial areas can be transported and accumulated, we selected the Qingyang county in Anhui province, where there are two small drainage basins developed wholly on carbonate bedrock, to compare the Cd speciation and activity between eluvium and alluvium, and to evaluate the risk of Cd pollution to the latter. By the application of systematic sampling and analysis of the bedrock, soil, and rice grain samples, and in comparison with the previously acknowledged "high background with low mobility" area in Guizhou, it was found that soil developed from alluvium has both higher total Cd and higher mobile Cd proportion than soil from the upland eluvium. A very high percentage of rice grain samples (51%) grown on the alluvial soil exceeded the food standard for Cd (0.2 mg kg-1). Therefore, the spatial division of alluvium and eluvium should be the first step in the assessment of the Cd risk in carbonate regions, and special attention should be given to soil developed from alluvium.


Assuntos
Cádmio/análise , Poluentes do Solo/análise , Carbonatos/análise , China , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Oryza , Solo , Tempo (Meteorologia)
7.
Nat Commun ; 11(1): 4876, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978378

RESUMO

In most crops, genetic and environmental factors interact in complex ways giving rise to substantial genotype-by-environment interactions (G×E). We propose that computer simulations leveraging field trial data, DNA sequences, and historical weather records can be used to tackle the longstanding problem of predicting cultivars' future performances under largely uncertain weather conditions. We present a computer simulation platform that uses Monte Carlo methods to integrate uncertainty about future weather conditions and model parameters. We use extensive experimental wheat yield data (n = 25,841) to learn G×E patterns and validate, using left-trial-out cross-validation, the predictive performance of the model. Subsequently, we use the fitted model to generate circa 143 million grain yield data points for 28 wheat genotypes in 16 locations in France, over 16 years of historical weather records. The phenotypes generated by the simulation platform have multiple downstream uses; we illustrate this by predicting the distribution of expected yield at 448 cultivar-location combinations and performing means-stability analyses.


Assuntos
Simulação por Computador , Produtos Agrícolas/genética , Genótipo , Incerteza , Tempo (Meteorologia) , Agricultura/métodos , DNA de Plantas , Grão Comestível/genética , França , Interação Gene-Ambiente , Modelos Genéticos , Fenótipo , Triticum/genética
8.
Int J Hyg Environ Health ; 229: 113587, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32917371

RESUMO

This study aimed to evaluate the relationship between weather factors (temperature, humidity, solar radiation, wind speed, and rainfall) and COVID-19 infection in the State of Rio de Janeiro, Brazil. Solar radiation showed a strong (-0.609, p < 0.01) negative correlation with the incidence of novel coronavirus (SARS-CoV-2). Temperature (maximum and average) and wind speed showed negative correlation (p < 0.01). Therefore, in this studied tropical state, high solar radiation can be indicated as the main climatic factor that suppress the spread of COVID-19. High temperatures, and wind speed also are potential factors. Therefore, the findings of this study show the ability to improve the organizational system of strategies to combat the pandemic in the State of Rio de Janeiro, Brazil, and other tropical countries around the word.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Clima Tropical , Tempo (Meteorologia) , Brasil/epidemiologia , Infecções por Coronavirus/virologia , Humanos , Umidade , Incidência , Pandemias , Pneumonia Viral/virologia , Temperatura , Vento
9.
Artigo em Inglês | MEDLINE | ID: mdl-32751311

RESUMO

This study analyzed the morbidity and mortality rates of the coronavirus disease (COVID-19) pandemic in different prefectures of Japan. Under the constraint that daily maximum confirmed deaths and daily maximum cases should exceed 4 and 10, respectively, 14 prefectures were included, and cofactors affecting the morbidity and mortality rates were evaluated. In particular, the number of confirmed deaths was assessed, excluding cases of nosocomial infections and nursing home patients. The correlations between the morbidity and mortality rates and population density were statistically significant (p-value < 0.05). In addition, the percentage of elderly population was also found to be non-negligible. Among weather parameters, the maximum temperature and absolute humidity averaged over the duration were found to be in modest correlation with the morbidity and mortality rates. Lower morbidity and mortality rates were observed for higher temperature and absolute humidity. Multivariate linear regression considering these factors showed that the adjusted determination coefficient for the confirmed cases was 0.693 in terms of population density, elderly percentage, and maximum absolute humidity (p-value < 0.01). These findings could be useful for intervention planning during future pandemics, including a potential second COVID-19 outbreak.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Densidade Demográfica , Tempo (Meteorologia) , Idoso , Infecções por Coronavirus/virologia , Surtos de Doenças , Previsões , Humanos , Umidade , Japão/epidemiologia , Morbidade , Pandemias , Pneumonia Viral/virologia , Temperatura
10.
Sci Total Environ ; 737: 140263, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32783854

RESUMO

BACKGROUND: In epidemic thunderstorm asthma (ETSA) events a large number of people develop asthma symptoms over a short period of time. This is thought to occur because of a unique combination of high amounts of pollen and certain meteorological conditions. However, the exact cause and mechanism of epidemic thunderstorm asthma remains unclear. OBJECTIVES: The objective of this study was to test the hypothesis that convergence lines may be a causative factor in ETSA events, by investigating whether convergence line weather events are associated with the occurrence of high asthma presentations days during the Victorian grass pollen season (October-December). METHODS: A case control method was used. All public hospitals within 75 km of the Melbourne weather radar were included, and data were taken from 2009 to 2017 during the Victorian grass pollen season. Cases hospital days were hospitals with a high number of asthma presentations within a 24-h period, and controls were hospitals with an expected number of asthma presentations. Exposure was defined as geographical proximity of a convergence line to the hospital case or control. RESULTS: Eighty-one case hospital days and 157 hospital day controls were included in the study. The odds of exposure to a convergence line were significantly higher for cases than for controls at all exposure distances. At 4 km, 80 of the 81 cases had been exposed to a convergence line. CONCLUSION: Convergence lines appear to be a necessary, but not sufficient, element in the cause of epidemic thunderstorm asthma. This is the first study to show a clear link between epidemic thunderstorm asthma and convergence lines.


Assuntos
Alérgenos , Asma , Austrália , Estudos de Casos e Controles , Humanos , Pólen/imunologia , Tempo (Meteorologia)
11.
Epidemiol Infect ; 148: e184, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32811577

RESUMO

Purpose: The novel coronavirus (severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)) first appeared in Wuhan, China, in December 2019, and rapidly spread across the globe. Since most respiratory viruses are known to show a seasonal pattern of infection, it has been hypothesised that SARS-CoV-2 may be seasonally dependent as well. The present study looks at a possible effect of atmospheric temperature, which is one of the suspected factors influencing seasonality, on the evolution of the pandemic. Basic procedures: Since confirming a seasonal pattern would take several more months of observation, we conducted an innovative day-to-day micro-correlation analysis of nine outbreak locations, across four continents and both hemispheres, in order to examine a possible relationship between atmospheric temperature (used as a proxy for seasonality) and outbreak progression. Main findings: There was a negative correlation between atmospheric temperature variations and daily new cases growth rates, in all nine outbreaks, with a median lag of 10 days. Principal conclusions: The results presented here suggest that high temperatures might dampen SARS-CoV-2 propagation, while lower temperatures might increase its transmission. Our hypothesis is that this could support a potential effect of atmospheric temperature on coronavirus disease progression, and potentially a seasonal pattern for this virus, with a peak in the cold season and rarer occurrences in the summer. This could guide government policy in both the Northern and Southern hemispheres for the months to come.


Assuntos
Infecções por Coronavirus , Modelos Estatísticos , Pandemias , Pneumonia Viral , Temperatura , Betacoronavirus , China , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Estudos Retrospectivos , Estações do Ano , Tempo (Meteorologia)
12.
J Environ Manage ; 271: 110706, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32778251

RESUMO

Severe fires associated to climate change and land cover changes are becoming more frequent in Mediterranean Europe. The influence of environmental drivers on fire severity, especially under different environmental conditions is still not fully understood. In this study we aim to determine the main environmental variables that control fire severity in large fires (>500 ha) occurring in fire-prone ecosystems under two different environmental conditions following a transition (Mediterranean-Oceanic)-Mediterranean climatic gradient within the Iberian Peninsula, and to provide management recommendations to mitigate fire damage. We estimated fire severity as the differenced Normalized Burn Ratio, through images obtained from Landsat 8 OLI. We also examined the relative influence of pre-fire vegetation structure (vegetation composition and configuration), pre-fire weather conditions, fire history and topography on fire severity using Random Forest machine learning algorithms. The results indicated that the severity of fires occurring along the transition (Mediterranean-Oceanic)-Mediterranean climatic gradient was primarily controlled by pre-fire vegetation composition. Nevertheless, the effect of vegetation composition was strongly dependent on interactions with fire recurrence and pre-fire vegetation structural configuration. The relationship between fire severity, weather and topographic predictors was not consistent among fires occurring in the Mediterranean-Oceanic transition and Mediterranean sites. In the Mediterranean-Oceanic transition site, fire severity was determined by weather conditions (i.e., summer cumulative rainfall), rather than being associated to topography, suggesting that the control exerted by topography may be overwhelmed by weather controls. Conversely, results showed that topography only had a major effect on fire severity in the Mediterranean site. The results of this study highlight the need to prioritise fuel treatments aiming at breaking fuel continuity and reducing fuel loads as an effective management strategy to mitigate fire damage in areas of high fire recurrence.


Assuntos
Ecossistema , Tempo (Meteorologia) , Mudança Climática , Europa (Continente) , Espanha
13.
Eur Rev Med Pharmacol Sci ; 24(15): 8226-8231, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32767354

RESUMO

OBJECTIVE: To explore whether the climate has played a role in the COVID-19 outbreak, we compared virus lethality in countries closer to the Equator with others. Lethality in European territories and in territories of some nations with a non-temperate climate was also compared. MATERIALS AND METHODS: Lethality was calculated as the rate of deaths in a determinate moment from the outbreak of the pandemic out of the total of identified positives for COVID-19 in a given area/nation, based on the COVID-John Hopkins University website. Lethality of countries located within the 5th parallels North/South on 6 April and 6 May 2020, was compared with that of all the other countries. Lethality in the European areas of The Netherlands, France and the United Kingdom was also compared to the territories of the same nations in areas with a non-temperate climate. RESULTS: A lower lethality rate of COVID-19 was found in Equatorial countries both on April 6 (OR=0.72 CI 95% 0.66-0.80) and on May 6 (OR=0.48, CI 95% 0.47-0.51), with a strengthening over time of the protective effect. A trend of higher risk in European vs. non-temperate areas was found on April 6, but a clear difference was evident one month later: France (OR=0.13, CI 95% 0.10-0.18), The Netherlands (OR=0.5, CI 95% 0.3-0.9) and the UK (OR=0.2, CI 95% 0.01-0.51). This result does not seem to be totally related to the differences in age distribution of different sites. CONCLUSIONS: The study does not seem to exclude that the lethality of COVID-19 may be climate sensitive. Future studies will have to confirm these clues, due to potential confounding factors, such as pollution, population age, and exposure to malaria.


Assuntos
Clima , Infecções por Coronavirus/mortalidade , Pneumonia Viral/mortalidade , Estações do Ano , Tempo (Meteorologia) , Betacoronavirus , Brunei/epidemiologia , Burundi/epidemiologia , Congo/epidemiologia , Infecções por Coronavirus/epidemiologia , Equador/epidemiologia , Guiné Equatorial/epidemiologia , Europa (Continente) , França/epidemiologia , Gabão/epidemiologia , Humanos , Ilhas do Oceano Índico/epidemiologia , Indonésia/epidemiologia , Quênia/epidemiologia , Malásia/epidemiologia , Melanesia/epidemiologia , Micronésia/epidemiologia , Países Baixos/epidemiologia , Pandemias , Papua Nova Guiné/epidemiologia , Pneumonia Viral/epidemiologia , Ruanda/epidemiologia , Samoa/epidemiologia , São Tomé e Príncipe/epidemiologia , Seicheles/epidemiologia , Singapura/epidemiologia , Somália/epidemiologia , Timor-Leste/epidemiologia , Clima Tropical , Uganda/epidemiologia , Reino Unido/epidemiologia
14.
Epidemiol Infect ; 148: e182, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32778180

RESUMO

The spread of COVID-19 is recent in India, which has within 4 months caused over 190 000 infections, as of 1 June 2020, despite four stringent lockdowns. With the current rate of the disease transmission in India, which is home to over 1.35 billion people, the infection spread is predicted to be worse than the USA in the upcoming months. To date, there is a major lack of understanding of the transmission dynamics and epidemiological characteristics of the disease in India, inhibiting effective measures to control the pandemic. We collected all the available data of the individual patients, cases and a range of parameters such as population distribution, testing and healthcare facilities, and weather, across all Indian states till May 2020. Numerical analysis was conducted to determine the effect of each parameter on the COVID-19 situation in India. A significant amount of local transmission in India initiated with travellers returning from abroad. Maharashtra, Tamil Nadu and Delhi are currently the top three infected states in India with doubling time of 14.5 days. The average recovery rate across Indian states is 42%, with a mortality rate below 3%. The rest 55% are currently active cases. In total, 88% of the patients experienced symptoms of high fever, 68% suffered from dry cough and 7.1% patients were asymptomatic. In total, 66.8% patients were males, 73% were in the age group of 20-59 years and over 83% recovered in 11-25 days. Approximately 3.4 million people were tested between 1 April and 25 May 2020, out of which 4% were detected COVID-19-positive. Given the current doubling time of infections, several states may face a major shortage of public beds and healthcare facilities soon. Weather has minimal effect on the infection spread in most Indian states. The study results will help policymakers to predict the trends of the disease spread in the upcoming months and devise better control measures.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Adulto , Betacoronavirus/fisiologia , Técnicas de Laboratório Clínico , Controle de Doenças Transmissíveis , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Feminino , Recursos em Saúde , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Densidade Demográfica , Viagem , Tempo (Meteorologia)
15.
Int J Biometeorol ; 64(10): 1795-1806, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32844296

RESUMO

The building of knowledge about current risks from changes in air temperature has been established as critical for informing the starting point for human health risk assessments in a climate-changing world. The study presented in this paper provides the application of the maximum/minimum temperature complex method in Colombia to identify the simultaneous behavior of daily extremes of air temperature and provide a tool to assess human health risks due to temperature variability. An established classification of mean temperatures exists for the country, and maximum and minimum temperatures have been studied but never as simultaneous variables. The max/min temperature complex analysis aims to describe the air temperature regime of a particular place by studying the frequency of simultaneous occurrence of extreme daily temperatures. The study consisted of the construction of a contingency table that combines the behavior of the daily maximum and minimum temperatures using a subdivision of 5 °C intervals. A 5-year (2010-2015)-long dataset of 171 weather stations from the entire territory was prepared by identifying, filtering, and completing the missing data. Frequencies of occurrence of each interval were arranged in descending order to select the intervals of frequencies above 10%. Then, they were classified into categories, types, and subtypes. Six categories, seven types, and fifty-one subtypes were identified and mapped to ascertain their geographical distribution. In contrast with other climate regime classifications, our study found a regionalization of daily extremes of temperature that can be analyzed in different scales of time and space to aid health risk analysis.


Assuntos
Clima , Tempo (Meteorologia) , Colômbia , Temperatura Alta , Humanos , Temperatura
17.
Sci Rep ; 10(1): 13442, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778673

RESUMO

Delhi, a tropical Indian megacity, experiences one of the most severe air pollution in the world, linked with diverse anthropogenic and biomass burning emissions. First phase of COVID-19 lockdown in India, implemented during 25 March to 14 April 2020 resulted in a dramatic near-zeroing of various activities (e.g. traffic, industries, constructions), except the "essential services". Here, we analysed variations in the fine particulate matter (PM2.5) over the Delhi-National Capital Region. Measurements revealed large reductions (by 40-70%) in PM2.5 during the first week of lockdown (25-31 March 2020) as compared to the pre-lockdown conditions. However, O3 pollution remained high during the lockdown due to non-linear chemistry and dynamics under low aerosol loading. Notably, events of enhanced PM2.5 levels (300-400 µg m-3) were observed during night and early morning hours in the first week of April after air temperatures fell close to the dew-point (~ 15-17 °C). A haze formation mechanism is suggested through uplifting of fine particles, which is reinforced by condensation of moisture following the sunrise. The study highlights a highly complex interplay between the baseline pollution and meteorology leading to counter intuitive enhancements in pollution, besides an overall improvement in air quality during the COVID-19 lockdown in this part of the world.


Assuntos
Poluentes Atmosféricos/análise , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Material Particulado/análise , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Quarentena/métodos , Tempo (Meteorologia) , Aerossóis/análise , Poluição do Ar/análise , Cidades/epidemiologia , Infecções por Coronavirus/virologia , Monitoramento Ambiental/métodos , Humanos , Índia/epidemiologia , Ozônio/análise , Pneumonia Viral/virologia , Temperatura
18.
PLoS One ; 15(8): e0236278, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841247

RESUMO

Rabies is a lethal viral disease and dogs are the major disease reservoir in the Philippines. Spatio-temporal variations in environmental factors are known to affect disease dynamics. Some rabies-affected countries considered investigating the role of weather components in driving rabies cases and it has helped them to strategize their control efforts. In this study, cointegration analysis was conducted between the monthly reported rabies cases and the weather components, such as temperature and precipitation, to verify the effect of weather components on rabies incidence in Davao City, Philippines. With the Engle-Granger cointegration tests, we found that rabies cases are cointegrated into each of the weather components. It was further validated, using the Granger causality test, that each weather component predicts the rabies cases and not vice versa. Moreover, we performed the Johansen cointegration test to show that the weather components simultaneously affect the number of rabies cases, which allowed us to estimate a vector-error correction model for rabies incidence as a function of temperature and precipitation. Our analyses showed that canine rabies in Davao City was weather-sensitive, which implies that rabies incidence could be projected using established long-run relationship among reported rabies cases, temperature, and precipitation. This study also provides empirical evidence that can guide local health officials in formulating preventive strategies for rabies control and eradication based on weather patterns.


Assuntos
Reservatórios de Doenças/virologia , Cães/virologia , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Raiva/epidemiologia , Tempo (Meteorologia) , Animais , Causalidade , Cidades/estatística & dados numéricos , Conjuntos de Dados como Assunto , Previsões/métodos , Humanos , Incidência , Modelos Estatísticos , Filipinas/epidemiologia , Raiva/prevenção & controle , Raiva/virologia , Vírus da Raiva , Análise Espaço-Temporal
19.
Ecotoxicol Environ Saf ; 204: 111035, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32768746

RESUMO

Coronavirus disease 2019 (COVID-19) was first detected in December 2019 in Wuhan, China, with 11,669,259 positive cases and 539,906 deaths globally as of July 8, 2020. The objective of the present study was to determine whether meteorological parameters and air quality affect the transmission of COVID-19, analogous to SARS. We captured data from 29 provinces, including numbers of COVID-19 cases, meteorological parameters, air quality and population flow data, between Jan 21, 2020 and Apr 3, 2020. To evaluate the transmissibility of COVID-19, the basic reproductive ratio (R0) was calculated with the maximum likelihood "removal" method, which is based on chain-binomial model, and the association between COVID-19 and air pollutants or meteorological parameters was estimated by correlation analyses. The mean estimated value of R0 was 1.79 ± 0.31 in 29 provinces, ranging from 1.08 to 2.45. The correlation between R0 and the mean relative humidity was positive, with coefficient of 0.370. In provinces with high flow, indicators such as carbon monoxide (CO) and 24-h average concentration of carbon monoxide (CO_24 h) were positively correlated with R0, while nitrogen dioxide (NO2), 24-h average concentration of nitrogen dioxide (NO2_24 h) and daily maximum temperature were inversely correlated to R0, with coefficients of 0.644, 0.661, -0.636, -0.657, -0.645, respectively. In provinces with medium flow, only the weather factors were correlated with R0, including mean/maximum/minimum air pressure and mean wind speed, with coefficients of -0.697, -0.697, -0.697 and -0.841, respectively. There was no correlation with R0 and meteorological parameters or air pollutants in provinces with low flow. Our findings suggest that higher ambient CO concentration is a risk factor for increased transmissibility of the novel coronavirus, while higher temperature and air pressure, and efficient ventilation reduce its transmissibility. The effect of meteorological parameters and air pollutants varies in different regions, and requires that these issues be considered in future modeling disease transmissibility.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Infecções por Coronavirus/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Poluição do Ar/análise , Betacoronavirus , Monóxido de Carbono/análise , China/epidemiologia , Coronavirus , Humanos , Dióxido de Nitrogênio/análise , Pandemias , Material Particulado/análise , Temperatura , Tempo (Meteorologia)
20.
Sci Total Environ ; 746: 141033, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32750577

RESUMO

Although impacts of extremely cold temperatures on human health have been widely studied, adverse effects of other extreme weather phenomena have so far received much less attention. We employed a high-quality long-term mortality time series (1982-2017) to evaluate impacts of extreme winter weather in the Czech Republic. We aimed to clarify whether compound events of extreme weather cause larger impacts on mortality than do each type of extreme if evaluated individually. Using daily data from the E-OBS and ERA5 datasets, we analyzed 9 types of extreme events: extreme wind gust, precipitation, snowfall, and sudden temperature and pressure changes. Relative mortality deviations from the adjusted baseline were used to estimate the immediate effect of the selected extreme events on excess mortality. The impact was adjusted for the effect of extreme cold. Extreme events associated with sudden rise of minimum temperature and pressure drops had generally significant impact on excess mortality (3.7% and 1.4% increase). The impacts were even more pronounced if these events occurred simultaneously or were compounded with other types of extremes, such as heavy precipitation, snowfall, maximum temperature rise, and their combinations (increase as great as 14.4%). Effects of some compound events were significant even for combinations of extremes having no significant impact on mortality when evaluated separately. On the other hand, a "protective" effect of pressure increases reduced the risk for its compound events. Meteorological patterns during extreme events linked to excess mortality indicate passage of a low-pressure system northerly from the study domain. We identified extreme winter weather events other than cold temperatures with significant impact on excess mortality. Our results suggest that occurrence of compound extreme events strengthen the impacts on mortality and therefore analysis of multiple meteorological parameters is a useful approach in defining adverse weather conditions.


Assuntos
Temperatura Baixa , Tempo (Meteorologia) , República Tcheca/epidemiologia , Humanos , Mortalidade , Estações do Ano , Temperatura
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