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1.
Environ Monit Assess ; 192(11): 686, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33029673

RESUMO

The paper describes the hydrography and vertical current structure along the shelf edge of South East Arabian Sea (SEAS) during summer and winter monsoons based on current profiles from moving Acoustic Doppler Current Profiler (ADCP). During summer monsoon, SEAS was characterized by upwelling with low saline water at the surface along the southern sector (8° N to 11° N). During winter, thermal structure was vertically homogeneous in the upper 80 m, and intrusion of low saline Bay of Bengal waters were found up to 14° N. In the southern sector, turbidity was more than the northern sector during winter and summer seasons. ADCP-derived current profiles during summer along 200-m isobath show dominant northward flow in the south, and southeasterly in the north as part of the West India Coastal Current (WICC). A comparison between ADCP current profiles and Ekman currents during summer indicates dominance of remote forcing (coastal Kelvin waves) over the local wind forcing in the 8-9° N sector whereas a combined influence of both remote forcing and wind in the 9-15° N sector. During winter, the direction of surface current reversed and was poleward generally except at the southern sector (7-8° N) where the flow was southwestward. Sector-wise comparison of ADCP and Ekman current showed less influence of wind on current fields throughout the sector except at south; wind has a major role in the current generation, whereas along the 8-15° N sector, the remote forcing dominates over the wind.


Assuntos
Tempestades Ciclônicas , Monitoramento Ambiental , Oceanos e Mares , Estações do Ano , Vento
2.
Colomb Med (Cali) ; 51(2): e4270, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33012885

RESUMO

Introduction: The COVID-19 disease pandemic is a health emergency. Older people and those with chronic noncommunicable diseases are more likely to develop serious illnesses, require ventilatory support, and die from complications. Objective: To establish deaths from respiratory infections and some chronic non-communicable diseases that occurred in Cali, before the SARS-CoV-2 disease pandemic. Methods: During the 2003-2019 period, 207,261 deaths were registered according to the general mortality database of the Municipal Secretary of Health of Cali. Deaths were coded with the International Classification of Diseases and causes of death were grouped according to WHO guidelines. Rates were standardized by age and are expressed per 100,000 people-year. Results: A direct relationship was observed between aging and mortality from respiratory infections and chronic non-communicable diseases. Age-specific mortality rates were highest in those older than 80 years for all diseases evaluated. Seasonal variation was evident in respiratory diseases in the elderly. Comments: Estimates of mortality rates from respiratory infections and chronic non-communicable diseases in Cali provide the baseline that will serve as a comparison to estimate the excess mortality caused by the COVID-19 pandemic. Health authorities and decision makers should be guided by reliable estimates of mortality and of the proportion of infected people who die from SARS-CoV-2 virus infection.


Assuntos
Causas de Morte/tendências , Doenças não Transmissíveis/epidemiologia , Infecções Respiratórias/epidemiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Colômbia/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/mortalidade , Humanos , Doenças não Transmissíveis/mortalidade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/mortalidade , Infecções Respiratórias/mortalidade , Fatores de Risco , Estações do Ano
3.
Nat Commun ; 11(1): 4945, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009378

RESUMO

Spring warming substantially advances leaf unfolding and flowering time for perennials. Winter warming, however, decreases chilling accumulation (CA), which increases the heat requirement (HR) and acts to delay spring phenology. Whether or not this negative CA-HR relationship is correctly interpreted in ecosystem models remains unknown. Using leaf unfolding and flowering data for 30 perennials in Europe, here we show that more than half (7 of 12) of current chilling models are invalid since they show a positive CA-HR relationship. The possible reason is that they overlook the effect of freezing temperature on dormancy release. Overestimation of the advance in spring phenology by the end of this century by these invalid chilling models could be as large as 7.6 and 20.0 days under RCPs 4.5 and 8.5, respectively. Our results highlight the need for a better representation of chilling for the correct understanding of spring phenological responses to future climate change.


Assuntos
Mudança Climática , Temperatura Baixa , Folhas de Planta/fisiologia , Estações do Ano , Betula/fisiologia , Temperatura Alta , Modelos Lineares , Modelos Biológicos
4.
Medicine (Baltimore) ; 99(41): e22684, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031338

RESUMO

Previous studies have indicated that the prevalence of gestational diabetes mellitus (GDM) was related to the season. However, there was no relevant information in Asia. The aim of this study was to determine whether there was seasonality of GDM and maternal blood glucose level in Taiwanese women.A total of 6396 pregnancies were enrolled between 2012 and 2014 in this retrospective study. A 2-step approach according to the Carpenter-Coustan criteria was used for GDM diagnosis. A generalized linear mixed model was used to estimate the effect of season on GDM diagnosis by adjusting for age, prepregnancy body mass index, parity, history of GDM, fetal sex, and the rate of weight gain.During the study period, 418 (6.5%) pregnancies were diagnosed as GDM. The model demonstrated an increased prevalence of GDM in spring and summer (odds ratio: 1.59, 95% confidence interval: 1.13-2.24; odds ratio: 1.59, 95% confidence interval: 1.14-2.23, respectively) compared to winter. For the glucose level variation, the model demonstrated an increase of 2.56 mg/dL glucose in the 50-g glucose challenge test in summer compared to winter. In glucose challenge test-positive pregnancies, the season also had an effect on the results of the 100-g 1-h, 2-h, and 3-h oral glucose tolerance tests, but no effect on the 100-g fasting oral glucose tolerance tests.GDM prevalence in Taiwan presents seasonal variation, with the highest risk during spring and summer due to post-glucose load level variations. These findings could serve as reference data for countries in Southeast Asia or areas with a similar climate.


Assuntos
Glicemia , Diabetes Gestacional/epidemiologia , Estações do Ano , Adulto , Diabetes Gestacional/sangue , Feminino , Humanos , Gravidez , Prevalência , Estudos Retrospectivos , Taiwan/epidemiologia , Adulto Jovem
5.
Nat Commun ; 11(1): 4933, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004787

RESUMO

The influence of seasons on biological processes is poorly understood. In order to identify biological seasonal patterns based on diverse molecular data, rather than calendar dates, we performed a deep longitudinal multiomics profiling of 105 individuals over 4 years. Here, we report more than 1000 seasonal variations in omics analytes and clinical measures. The different molecules group into two major seasonal patterns which correlate with peaks in late spring and late fall/early winter in California. The two patterns are enriched for molecules involved in human biological processes such as inflammation, immunity, cardiovascular health, as well as neurological and psychiatric conditions. Lastly, we identify molecules and microbes that demonstrate different seasonal patterns in insulin sensitive and insulin resistant individuals. The results of our study have important implications in healthcare and highlight the value of considering seasonality when assessing population wide health risk and management.


Assuntos
Exposição Ambiental , Resistência à Insulina/fisiologia , Redes e Vias Metabólicas/fisiologia , Microbiota/fisiologia , Estações do Ano , Adulto , Idoso , Glicemia/análise , Glicemia/metabolismo , California , Análise por Conglomerados , Feminino , Nível de Saúde , Humanos , Insulina/metabolismo , Estudos Longitudinais , Masculino , Metabolômica , Pessoa de Meia-Idade , RNA-Seq
6.
J Dent Hyg ; 94(5): 14-21, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33008945

RESUMO

Purpose: Children of Hispanic seasonal or migrant farmworkers in the United States (US) experience high rates of Early Childhood Caries (ECC) and have high rates of untreated dental caries. The purpose of this study was to explore Hispanic seasonal farmworker caregivers' beliefs and/or perceptions regarding ECC their children's oral health.Methods: A qualitative explanatory model interview approach was used with a purposive sample of Hispanic parents/caregivers, working and residing in Orange and Ulster Counties, New York. The Explanatory Model Interview Catalogue (EMIC) was used as a guide to the semi-structured, recorded interviews conducted in locations selected by the participants. The texts were independently read and thematically analyzed by two researchers.Results: A total of 20 parents/caregivers consented to participate. Six themes were identified for the components of the EMIC and included: etiology: eating candy/sweets (65%); sign/symptoms of decay: tooth color change (50%); pathophysiology: not brushing daily (75%); course of disease/impact on daily life: appearance (40%); impact of caries on child's future health: affects child until adult teeth erupt (25%); treatment for pain: tooth brushing (55%). Over half of the respondents (55%) indicated that getting dental care for their children was a priority.Conclusion: Results from this study showed that Hispanic seasonal farmworkers have a desire to maintain their children's oral health. However, they lacked knowledge in some key concepts related to the disease process and prevention of ECC. Caregivers need additional oral health education with consideration for oral health literacy.


Assuntos
Cuidadores , Cárie Dentária , Adulto , Criança , Pré-Escolar , Fazendeiros , Hispano-Americanos , Humanos , New York , Estações do Ano
7.
J Environ Qual ; 49(2): 292-303, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016415

RESUMO

Artificial subsurface drainage is necessary to maintain agricultural production in the soils and climate of north-central Iowa. However, it can result in adverse environmental impacts, because it intercepts and diverts some water and soluble NO3 -N directly to streams. We investigated the impact of no-till and a winter rye cover crop (Secale cereale L.) on seasonal and annual NO3 -N concentration and loading in leachate from a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation. The eight treatments are chisel plow (CT), chisel plow with winter cereal rye (CTr), no-till (NT), and no-till with winter cereal rye (NTr), with "-C" indicating corn and "-S" indicating soybeans. Plots with artificial subsurface drainage were monitored for water quality from 2011 to 2015. The NT and CTr treatments consistently decreased NO3 -N loss on the seasonal and annual scales compared with CT. Compared with NT, NTr did not reduce NO3 -N loading nor concentration in leachate, probably because of low NO3 leaching potential from NT combined with low rye cover crop biomass throughout the study with NT. The 5-yr average annual NO3 -N concentrations were: 16.9 mg L-1 with CT-S, 16.7 mg L-1 with CT-C, 12.6 mg L-1 with NT-S, 12.0 mg L-1 with CTr-S, 11.8 mg L-1 with CTr-C, 11.4 mg L-1 with NTr-S and NTr-C, and 11.1 mg L-1 with NT-C. Overall, both no-till and a cover crop showed potential for improving N management for water quality.


Assuntos
Nitrogênio/análise , Secale , Agricultura , Iowa , Estações do Ano
8.
J Environ Qual ; 49(5): 1264-1272, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016462

RESUMO

Leptospirosis is an emerging zoonotic disease in the Caribbean region and the island of Puerto Rico. Information on the presence of pathogenic Leptospira in rivers and streams of Puerto Rico is currently lacking. This study aimed to evaluate seasonal shifts in the presence of pathogenic leptospires and the level of Escherichia coli from 32 coastal locations in Puerto Rico's dry and wet seasons. Physicochemical parameters (temperature, salinity, pH, and dissolved oxygen) were determined at each site. The temperature (25.8 °C) and pH (average 7.6) values were all within acceptable USEPA regulatory standards. Thirty-eight percent of the sites of the dry season and 28% of the wet season sites contained dissolved oxygen levels ≤4 mg L-1 , which is relatively low. In the dry season, 19 sites (59%) and 18 (56%) of the wet season sites had E. coli counts >410 most probable number (MPN) 100 ml-1 and would be considered unsafe for recreational use. The lipl32 gene quantitative polymerase chain reaction assay was used for the detection of pathogenic leptospires in the samples. Low concentrations of pathogenic leptospires (<60 genome copies 100 ml-1 ) at Camuy, Espíritu Santo, Río Guayanilla, Quebrada Majagual, and Río Fajardo were detected during the wet season. Pathogenic leptospires were detected (∼40 genome copies 100 ml-1 ) at only one site, Loíza, during the dry season. There was no predictable relationship between the physicochemical parameters, concentrations of E. coli, and the presence of pathogenic leptospires in water samples.


Assuntos
Escherichia coli , Leptospira , Porto Rico , Rios , Estações do Ano
9.
BMC Public Health ; 20(1): 1524, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33032561

RESUMO

BACKGROUND: Arrhythmia is a common cardiovascular event that is associated with increased cardiovascular health risks. Previous studies that have explored the association between air pollution and arrhythmia have obtained inconsistent results, and the association between the two in China is unclear. METHODS: We collected daily data on air pollutants and meteorological factors from 1st January 2014 to 31st December 2016, along with daily outpatient visits for arrhythmia in Hangzhou, China. We used a quasi-Poisson regression along with a distributed lag nonlinear model to study the association between air pollution and arrhythmia morbidity. RESULTS: The results of the single-pollutant model showed that each increase of 10 µg/m3 of Fine particulate matter (PM2.5), Coarse particulate matter (PM10), Sulphur dioxide (SO2), Nitrogen dioxide (NO2), and Ozone (O3) resulted in increases of 0.6% (- 0.9, 2.2%), 0.7% (- 0.4, 1.7%), 11.9% (4.5, 19.9%), 6.7% (3.6, 9.9%), and - 0.9% (- 2.9, 1.2%), respectively, in outpatient visits for arrhythmia; each increase of 1 mg/m3 increase of carbon monoxide (CO) resulted in increase of 11.3% (- 5.9, 31.6%) in arrhythmia. The short-term effects of air pollution on arrhythmia lasted 3 days, and the most harmful effects were observed on the same day that the pollution occurred. Results of the subgroup analyses showed that SO2 and NO2 affected both men and women, but differences between the sexes were not statistically significant. The effect of SO2 on the middle-aged population was statistically significant. The effect of NO2 was significant in both the young and middle-aged population, and no significant difference was found between them. Significant effects of air pollution on arrhythmia were only detected in the cold season. The results of the two-pollutants model and the single-pollutant model were similar. CONCLUSIONS: SO2 and NO2 may induce arrhythmia, and the harmful effects are primarily observed in the cold season. There is no evidence of PM2.5, PM10, CO and O3 increasing arrhythmia risk. Special attention should be given to sensitive populations during the high-risk period.


Assuntos
Poluição do Ar/efeitos adversos , Assistência Ambulatorial/estatística & dados numéricos , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/terapia , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estações do Ano
10.
Environ Monit Assess ; 192(11): 716, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33083864

RESUMO

In this research, sea surface temperature (SST) variability for the summer season in the Aegean Sea was analysed over a period of 30 years by using the Landsat thermal infrared bands. A total of 88 Landsat 5, 7, and 8 thermal infrared satellite images from June, July, and August were used for each year from 1989 to 2019. To estimate SST from the thermal infrared band data, thermal infrared sensor at-sensor spectral radiance, and thermal infrared sensor top-of-atmosphere brightness temperatures were used. SST pixel values were extracted from thermal images for the 3-month summer season of each year. In order to validate the findings, regression analysis was performed between the Mediterranean Sea Ultra High Resolution SST L4 data and Landsat data for the 2008-2019 period. Regression constant R-squared values were found to be 0.9672 for June, 0.9550 for July, 0.9634 for August, and 0.9634 for all summer seasons. It was calculated that the minimum value of the average SST was 18.44 ± 2.87 °C in 1992, and the maximum value of the average SST was 23.45 ± 0.70 °C in 2018. According to the Landsat data, over the past 30 years, the annual average SST changes were estimated to be 0.11 °C, and the total changes of average SST were estimated to be 3.19 ± 1.26 °C. As a result of the analysis and the validation, we can see that there is a rising trend in sea surface temperature in the Aegean Sea. However, it is difficult to determine whether this upward trend is related to global climate change.


Assuntos
Mudança Climática , Monitoramento Ambiental , Mar Mediterrâneo , Estações do Ano , Temperatura
12.
Sci Total Environ ; 741: 140188, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32886981

RESUMO

CONTEXT: A number of studies have shown that cold has an important impact on human health. However, almost no studies focused on cold warning systems to prevent those health effects. For Nordic regions, like the province of Quebec in Canada, winter is long and usually very cold with an observed increase in mortality and hospitalizations throughout the season. However, there is no existing system specifically designed to follow in real-time this mortality increase throughout the season and to alert public health authorities prior to cold waves. OBJECTIVE: The aim is to establish a watch and warning system specifically for health impacts of cold, applied to different climatic regions of the province of Quebec. METHODOLOGY: A methodology previously used to establish the health-heat warning system in Quebec is adapted to cold. The approach identifies cold weather indicators and establishes thresholds related to extreme over-mortality or over-hospitalization events in the province of Quebec, Canada. RESULTS AND CONCLUSION: The final health-related thresholds proposed are between (-15 °C, -23 °C) and (-20 °C, -29 °C) according to the climatic region for excesses of mortality, and between (-13 °C, -23 °C) and (-17 °C, -30 °C) for excesses of hospitalization. These results suggest that the system model has a high sensitivity and an acceptable number of false alarms. This could lead to the establishment of a cold-health watch and warning system with valid indicators and thresholds for each climatic region of Quebec. It can be seen as a complementary system to the existing one for heat warnings, in order to help the public health authorities to be well prepared during an extreme cold event.


Assuntos
Temperatura Baixa , Temperatura Alta , Canadá , Humanos , Quebeque , Estações do Ano
13.
Sci Total Environ ; 741: 140466, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32886993

RESUMO

There is a growing concern about the fate of antibiotic resistance genes (ARGs) during wastewater treatment and their potential impacts on the receiving water bodies. We hypothesised that the quantity of ARGs in effluents may be related to the size of wastewater treatment plants (WWTPs) and sampling season. To date, only several attempts have been made to investigate the impact of the above factors at the catchment scale. Therefore, the goal of the present study was to explore possible differences in the quantity of ARGs in treated wastewater from small, medium-sized and large WWTPs in the catchment of the Pilica River (9258 km2). The impact of treated wastewater on the concentration of ARGs was also determined along the river continuum from upland to lowland segments to the point of confluence with the Vistula (342 km). Treated effluent was sampled in 17 WWTPs, and river water was sampled in 7 sampling sites in four seasons. The concentrations of blaTEM, tet(A), ermF, sul1 and aac(6')-Ib-cr genes, the integrase gene intI1 and the 16S rRNA gene were analysed by quantitative PCR. The physical and chemical parameters and nutrient concentrations (23 various parameters) in the analysed samples were determined. The highest absolute concentrations of the studied genes were noted in effluent samples from small WWTPs (p < 0.01). The concentration of ARGs (gene copies/mL) peaked in winter and spring samples (p < 0.04). The results of statistical analyses indicate that in small WWTPs, the absolute concentration of ARGs can be predicted based on the biochemical oxygen demand, in routine water analyses. However, none of the studied parameters supported predictions of ARG abundance in medium-sized and large WWTPs or in river water.


Assuntos
Rios , Águas Residuárias/análise , Antibacterianos , Resistência Microbiana a Medicamentos , Genes Bacterianos , Prevalência , RNA Ribossômico 16S , Estações do Ano
14.
BMC Infect Dis ; 20(1): 643, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873241

RESUMO

BACKGROUND: The transmission features and the feasibility of containing shigellosis remain unclear among a population-based study in China. METHODS: A population-based Susceptible - Exposed - Infectious / Asymptomatic - Recovered (SEIAR) model was built including decreasing the infectious period (DIP) or isolation of shigellosis cases. We analyzed the distribution of the reported shigellosis cases in Hubei Province, China from January 2005 to December 2017, and divided the time series into several stages according to the heterogeneity of reported incidence during the period. In each stage, an epidemic season was selected for the modelling and assessing the effectiveness of DIP and case isolation. RESULTS: A total of 130,770 shigellosis cases were reported in Hubei Province. The median of Reff was 1.13 (range: 0.86-1.21), 1.10 (range: 0.91-1.13), 1.09 (range: 0.92-1.92), and 1.03 (range: 0.94-1.22) in 2005-2006 season, 2010-2011 season, 2013-2014 season, and 2016-2017 season, respectively. The reported incidence decreased significantly (trend χ2 = 8260.41, P <  0.001) among four stages. The incidence of shigellosis decreased sharply when DIP implemented in three scenarios (γ = 0.1, 0.1429, 0.3333) and when proportion of case isolation increased. CONCLUSIONS: Year heterogeneity of reported shigellosis incidence exists in Hubei Province. It is feasible to contain the transmission by implementing DIP and case isolation.


Assuntos
Disenteria Bacilar/epidemiologia , Epidemias , Modelos Teóricos , Infecções Assintomáticas , China/epidemiologia , Simulação por Computador , Coleta de Dados , Disenteria Bacilar/prevenção & controle , Disenteria Bacilar/transmissão , Estudos de Viabilidade , Humanos , Incidência , Estações do Ano
15.
Mar Environ Res ; 160: 105037, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907738

RESUMO

Marine zooplankton are increasingly being affected by recent environmental changes, such as climate change, and respond with profound spatial relocations and shifts in phenology and physiology. In order to predict whether populations are able to persist or adapt to such new conditions, it is essential to understand the molecular basis of such adaptations, which ultimately get translated into these physiological responses. To explore variation in population gene expression across time and space, we investigated transcriptome-level profiles of the calanoid copepod Temora longicornis, that were collected at four different locations in the Belgian Part of the North Sea (BPNS) on three different time points (April, June, October) in 2018. RNA-seq analysis of field collected adults identified large seasonal differences in gene expression, mainly between spring-summer and autumn samples. The largest log-fold changes occurred in a set of genes encoding for ribosomal and myosin (heavy chain) transcripts. Enrichment analysis revealed a strong seasonal pattern in vitellogenin, cuticle and glycolytic gene expression as well. We also found a positive correlation between vitellogenin expression and densities of T. longicornis. No clear spatial variation in expression patterns was found in the BPNS. This study underlines the potential of field gene expression studies for biomonitoring purposes and the significance of considering seasonal variation in future studies.


Assuntos
Copépodes , Expressão Gênica , Animais , Bélgica , Copépodes/genética , Mar do Norte , Estações do Ano , Zooplâncton
16.
Zhonghua Yi Xue Za Zhi ; 100(34): 2696-2700, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-32921019

RESUMO

Objective: To analyze the epidemic characteristics of hand, foot and mouth disease (HFMD) in Beijing and explore the short-term lag effect of daily average temperature on HFMD. Methods: The incidence data and meteorological data of HFMD were collected from Xicheng District, Chaoyang District, and Changping District of Beijing between January 2009 and December 2018. The dose-response relationship and short-term lag effect of temperature and HFMD incidence were explored by the distributed lag non-linear model (DNLM). Results: From 2009 to 2018, a total of 97 210 cases of HFMD were confirmed in Xicheng District, Chaoyang District, and Changping District of Beijing. The incidence rate of HFMD in Xicheng district was 71.83/100 000, which was the lowest in three districts. The total annual average incidence was 146.89/100 000 in the three districts. The cases were concentrated from May to July, with a small peak in October to November. The ratio of male to female was 1.49∶1, and the median age of the patients was 3.08 (1.89, 4.39) years old, which showed a decreasing trend in children under 6 years old (Z=-30.11, P<0.01). The DNLM showed that the cumulative relative risk (RR) curve had a bimodal distribution, with RR of 1.36 (95%CI: 1.05-1.76) and 1.35 (95%CI: 1.10-1.66), and the peak values appeared at 4 ℃ and 26 ℃, respectively. Conclusions: The incidence rate of HFMD in Xicheng was the lowest in three districts of Beijing. In addition, the incidence of HFMD is seasonal, and the incidence is higher in spring and summer than that in autumn and winter. Daily average temperature had a lag effect on HFMD, which was different between high temperature and low temperature.


Assuntos
Doença de Mão, Pé e Boca , Pequim , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Masculino , Estações do Ano , Temperatura
17.
J Environ Sci (China) ; 97: 1-10, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933723

RESUMO

Variations of levels, possible source and air mass transmission were investigated for 16 USEPA priority-controlled PAHs in PM2.5 during 2018 Chinese Spring Festival (CSF) in Xiangyang City, central China which is the North-South pollutant airmass transport channel of China. Totally 37 samples were collected. Mass concentrations of Σ16PAHs for the Pre-CSF day (Pre-CSFD), during the CSF day (CSFD) and after the CSF day (Af-CSFD) are 33.78 ± 17.68 ng/m3, 22.98 ± 6.49 ng/m3, and 8.99 ± 4.44 ng/m3, respectively. High resolution samples showed that Σ16PAHs are higher in the morning (06:00-11:00) or afternoon (11:30-16:30), than those in the evening (17:00-22:00) and at night (22:30-05:30), whereas the result is reversed during the CSFD. Fireworks burning can obviously increase the mass concentration of PAHs. Air mass trajectory indicated that Xiangyang is a sink area of pollutants for northwest and southeast, and the sources of the northeast and southwest. The air mass only can be transmitted out through northeast and southwest. It is effective for improvement of air quality in Wuhan and Hunan to control fireworks emission in Henan and local areas. Fireworks burning was an important source for PAHs during CSFD, biomass, coal combustion, and traffic emission were the main sources of PAHs for Pre-CSFD and Af-CSFD periods. The health risk on the CSFD was higher than the acceptable levels, especially during the intensive fireworks burning, the risk value far exceed 1.0 × 10-4, controlling burning fireworks is required.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , China , Cidades , Monitoramento Ambiental , Férias e Feriados , Material Particulado/análise , Estações do Ano
18.
J Environ Sci (China) ; 97: 149-161, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933730

RESUMO

Transboundary and domestic aerosol transport during 2018-2019 affecting Bangkok air quality has been investigated. Physicochemical characteristics of size-segregated ambient particles down to nano-particles collected during 2017 non-haze and 2018-2019 haze periods were analyzed. The average PM2.5 concentrations at KU and KMUTNB sites in Bangkok, Thailand during the haze periods were about 4 times higher than in non-haze periods. The highest average organic carbon and elemental carbon concentrations were 4.6 ± 2.1 µg/m3 and 1.0 ± 0.4 µg/m3, respectively, in PM0.5-1.0 range at KU site. The values of OC/EC and char-EC/soot-EC ratios in accumulation mode particles suggested the significant influence of biomass burning, while the nuclei and coarse mode particles were from mixed sources. PAH concentrations during 2018-2019 haze period at KU and KMUTNB were 3.4 ± 0.9 ng/m3 and 1.8 ± 0.2 ng/m3, respectively. The PAH diagnostic ratio of PM2.5 also suggested the main contributions were from biomass combustion. This is supported by the 48-hrs backward trajectory simulation. The higher PM2.5 concentrations during 2018-2019 haze period are also associated with the meteorological conditions that induce thermal inversions and weak winds in the morning and evening. Average values of benzo(a)pyrene toxic equivalency quotient during haze period were about 3-6 times higher than during non-haze period. This should raise a concern of potential human health risk in Bangkok and vicinity exposing to fine and ultrafine particulate matters in addition to regular exposure to traffic emission.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar , Aerossóis/análise , Biomassa , Carbono/análise , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Tailândia
19.
J Environ Sci (China) ; 97: 45-53, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933739

RESUMO

Estuarine wetland is the transitional interface linking terrestrial with marine ecosystems, and wetland microbes are crucial to the biogeochemical cycles of nutrients. The soil samples were collected in four seasons (spring, S1; summer, S2; autumn, S3; and winter, S4) from Suaeda wetland of Shuangtaizi River estuary, Northeast China, and the variations of bacterial community were evaluated by high-throughput sequencing. Soil properties presented a significant seasonal change, including pH, carbon (C) and total nitrogen (TN), and the microbial diversity, richness and structure also differed with seasons. Canonical correspondence analysis (CCA) and Mantel tests implied that soil pH, C and TN were the key factors structuring the microbial community. Gillisia (belonging to Bacteroidetes) and Woeseia (affiliating with Gammaproteobacteria) were the two primary components in the rhizosphere soils, displaying opposite variations with seasons. Based on PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) prediction, the xenobiotics biodegradation related genes exhibited a seasonal decline, while the majority of biomarker genes involved in nitrogen cycle showed an ascending trend. These findings could advance the understanding of rhizosphere microbiota of Suaeda in estuarine wetland.


Assuntos
Chenopodiaceae , China , Estuários , Filogenia , Rios , Estações do Ano , Solo , Microbiologia do Solo , Áreas Alagadas
20.
J Environ Sci (China) ; 97: 85-95, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32933743

RESUMO

Agriculture-oriented cities in Northeastern China have experienced frequent atmospheric pollution events. Deeper understandings of the pollution characteristics, haze causes and effects of management on local air quality are crucial for conducting integrated management approaches for the sustainable development of agriculture-oriented cities. Taking a typical agriculture-dominant city (i.e., Suihua) in Northeast China, we analyzed in detail the characteristics and causes of atmospheric pollution and evaluated the straw-burning prohibition using multisource data. The results showed a clear temporal pattern of air quality index (AQI) on an annual scale (i.e., 2015-April 2019), with two typical pollution periods occurring in late autumn and early spring. The large areas of concentrated straw burning at local and regional scales accounted for the first period (i.e., October and November), while dust emissions and farming disturbances comprised the second period. The interannual variation in pollution periods among these years was large, showing similar trends from 2015 to 2017 and the postponed late-autumn pollution period in 2018. Our evaluation has shown that the prohibition effect of straw burning significantly improved air quality in 2018, with a reduction of 59% ± 88% in the PM2.5 concentrations in October and November compared to 2015-2017. However, From October to April of the following year, the improvement effect was not significant due to postponement of straw burning to February or March. Our analysis also highlighted the roles of meteorological conditions, Therefore, combined with the promotion of straw utilization, scientifically prescribed burning considering the burning amount and location, meteorological conditions and regional transportation should be implemented.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Agricultura , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano
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