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1.
Sci Total Environ ; 803: 149735, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34492490

RESUMO

Currently, most regional thermal environment (RTE) studies in urban agglomerations focus on developing countries, especially China. However, there is still a lack of comparative studies on the RTEs of urban agglomerations between China and other developed countries, such as the United States. This paper used the Beijing-Tianjin-Hebei (BTH) agglomeration in China and Boswash (the highly urbanized area extending from Boston to Washington) in the United States as examples to investigate the differences in land development patterns, RTEs and their relationship between the agglomerations of China and America. The results showed that the land development patterns of BTH and Boswash were different, as evidenced by the spatial pattern of land development intensity (LDI) and impervious surface configuration. In terms of the RTE, the sub-high land surface temperature (LST) zones were aggregated in a large and compact patch in central and northern BTH. However, the sub-high zones of the cities in Boswash were relatively separate. Moreover, the land development pattern of Boswash showed a stronger relationship with the RTE than that of BTH did. Global Moran's I between the LDI and LST in Boswash was higher than that in BTH. In addition, the correlation between impervious surface configuration and LST in Boswash was stronger than that in BTH, and this correlation was more controlled by LDI in Boswash. This study also indicated that BTH should change the land development pattern to prevent the further expansion of aggregated sub-high LST zones and control the proximity of high LST zones in cities in central and southern BTH, however, Boswash should adopt some local heat management approaches (installing cool and green roofs and creating more green space) in the core areas to help reduce the very high temperatures in the already highly developed areas where the largest fraction of people live.


Assuntos
Monitoramento Ambiental , Pequim , Boston , China , Cidades , Humanos , Washington
2.
Sci Total Environ ; 803: 150079, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34525721

RESUMO

Characterizing the relationship between vegetation phenology and urbanization indicators is essential to understand the impacts of human activities on urban ecosystems. In this study, we explored the response of vegetation phenology to urbanization in Beijing (China) during 2001-2018, using impervious surface area (ISA) and the information of urban-rural gradients (i.e., concentric rings from the urban core to surrounding rural areas) as the urbanization indicators. We found the change rates of vegetation phenology in urban areas are 1.3 and 1.1 days per year for start of season (SOS) and end of season (EOS), respectively, about three times faster than that in forest. Moreover, we found a divergent response of SOS with the increase of ISA, which differs from previous results with advanced SOS in the urban environment than surrounding rural areas. This might be attributed to the mixed land cover types and the thermal environment caused by the urban heat island in the urban environment. Similarly, a divergent pattern of phenological indicators along the urban-rural gradient shows a non-linear response of vegetation phenology to urbanization. These findings provide new insights into the complicated interactions between vegetation phenology and urban environments. High-resolution weather data are required to support process-based vegetation phenology models in the future, particularly under different global urbanization and climate change scenarios.


Assuntos
Ecossistema , Urbanização , Pequim , China , Cidades , Temperatura Alta , Humanos , Desenvolvimento Vegetal
3.
Sci Total Environ ; 803: 149980, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34525764

RESUMO

Dust storm particles have been one of the important contributors to global aerosol loading, affecting human health and climate system. Beijing, a megapolitan city, experienced two severe dust storms in spring of 2015, with maximum hourly-mean PM10 mass concentrations exceeding 1000 µg/m3. The first dust storm (Dust 1) was from east area of Gobi Desert about 850 km in the north of Beijing and the second (Dust 2) was from west area of Gobi Desert about 1500 km in the northwest of Beijing. Morphologies and elemental compositions of dust particles were identified using high-resolution electron microscopy. The statistical analysis showed that the number fractions of mineral dust particles during the two dust storm episodes were 85.3% and 95.4%, respectively. Clay minerals were the most abundant among mineral particles, with a number fraction larger than 50%, followed by quartz particles (17.3% and 14.8%) and feldspar. Feldspar and carbonate particles accounted for 14.8% and 3.4% of mineral particles in Dust 1, and 9.9% and 13.6% in Dust 2, with the difference due to the different source areas. When the dust storms directly migrated to Beijing, the occurrence of S-containing mineral particles and the relative weight ratio of S in individual mineral particles were extremely low, indicating limited production of sulfate on the dust-storm particles in the atmosphere, regardless of the differences of source areas, migration paths, and mineralogical components. After the peaks of dust storms passed, the occurrence of S on the mineral particles were much higher, although the relative weight ratios of S in the mineral particles was still very small. This result suggests that most of the mineral particles underwent heterogeneous reactions, but the reaction rates were low.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , Poeira/análise , Monitoramento Ambiental , Humanos , Minerais/análise , Tamanho da Partícula
4.
Sci Total Environ ; 802: 149695, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438127

RESUMO

Particle number size distribution (PNSD) is of importance for understanding the mechanisms of particle growth, haze formation and climate impacts. However, the measurements of PNSD aloft in megacities are very limited. Here we report the first simultaneous winter measurements of size-resolved particle number concentrations along with collocated gaseous species and aerosol composition at ground level and 260 m in Beijing. Our study showed that the vertical differences of particle number concentrations between ground level and aloft varied significantly as a function of particle size throughout the study. Further analysis illustrated the impacts of boundary dynamics and meteorological conditions on the vertical differences of PNSD. In particular, the temperature and relative humidity inversions were one of the most important factors by decoupling the boundary layer into different sources and processes. Positive matrix factorization analysis identified six sources of PNSD at both ground level and city aloft. The local source emissions dominantly contributed to Aitken-mode particles, and showed the largest vertical gradients in the city. Comparatively, the regional particles were highly correlated between ground level and city aloft, and the vertical differences were relatively stable throughout the day. Our results point towards a complex vertical evolution of PNSD due to the changes in boundary layer dynamics, meteorological conditions, sources, and processes in megacities.


Assuntos
Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Estações do Ano
5.
Sci Total Environ ; 802: 149849, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455273

RESUMO

Promoting land use planning through ecosystem service (ES) protection is a crucial approach for maintaining landscape sustainability. Identifying ES bundles to serve landscape functional zoning can provide a new perspective for sustainable land use planning. Taking the Beijing metropolitan region as a study area, we quantitatively assessed the spatiotemporal distributions of multiple ESs, from 1980 to 2017, based on land use changes. By combining ES patterns and comprehensive ecosystem service (CES), distinct ES bundles were identified through the clustering method. Based on the ES bundles, landscape functional zones were then established. We further developed improved land use scenarios to conserve ESs in selected towns of different functional zones by exploring dominant factors influencing ESs. Results showed that most of ESs decreased due to the expansion of developed lands. According to the classification of ES bundles, Beijing can be classified into three landscape functional zones at town level: the ecological conservation region (ECR), food production region (FPR), and urban development region (UDR). For each landscape functional zone, the town with the greatest decline in CES value was selected. Associated with the influencing factors of ESs, local land use patterns, and ecological protection policies, corresponding multi-step improved land use scenarios were designed. These scenarios were demonstrated to be effective in conserving ESs in the selected towns: (1) the agricultural expansion scenario, which enhanced food provision services in the ECR; (2) the forest conservation scenario, which enhanced habitat and recreational services in the FPR; and (3) the developed land optimization scenario, which enhanced a range of regulating services in the UDR. Overall, this study used landscape functional zoning as a nexus to connect ES patterns and land use management. The optimized land use strategies can provide references for conserving ESs and enhancing landscape sustainability in Beijing and other similar metropolitan areas worldwide.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Pequim , China , Florestas
6.
Sci Total Environ ; 804: 150028, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798715

RESUMO

Estazolam (EZ) is a long-acting benzodiazepine (BZD) drug with high clinical consumption in China to treat anxiety, depression and other syndromes. Recently, it has been found as a leading potentially inappropriate medication among hospitalized elderly patients, increasing the risk of falls. It is discharged into the aquatic environment after use and has been frequently detected, ultimately affecting the safety of drinking water. In the present study, the reaction of EZ during chlorination disinfection was investigated in detail with regard to its transformation and kinetics. By means of ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS), four main disinfection byproducts (DBPs) were tentatively identified, and the transformation pathways were speculated to be cleavage at the imine linkage and oxidation on the diazepinone ring. The chlorination reaction rate in the pseudo-first-order kinetic model was significantly affected by free available chlorine (FAC) and pH. The increase in pH value led to a decrease in the reaction rate, while a higher dosage of chlorine resulted in a faster kinetic rate. We further estimated the potential toxicities of EZ and its DBPs using quantitative structure-activity relationship (QSAR) software tools. DBPs exhibited much higher toxicity than EZ and exhibited developmental toxicity and mutagenicity. Finally, a total of 108 drinking water samples were collected in the wet and dry seasons to determine actual residue changes in real environmental conditions. The detection frequency was 29% for EZ, and the highest concentration of 0.60 ng L-1 was found for its DBPs in tap water. No seasonal variations in concentration were observed. Overall, the results indicate that EZ and its DBPs may persist in drinking water, posing potential risks to public health.


Assuntos
Desinfetantes , Água Potável , Preparações Farmacêuticas , Poluentes Químicos da Água , Purificação da Água , Idoso , Pequim , Benzodiazepinas , Cloro , Desinfecção , Estazolam , Halogenação , Humanos , Poluentes Químicos da Água/análise
7.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(11): 1115-1119, 2021 Nov 09.
Artigo em Chinês | MEDLINE | ID: mdl-34763407

RESUMO

The Beijing National Medical School Faculty of Dentistry was established in 1943. This article reviewed the files preserved in Beijing Municipal Archices and presented the early background of the establishment including the approval process, formulation of teaching plans and design of the curriculums. These historical records provide us with thought-provoking insights into the evolution of the stomatological discipline and subsequent development of various sub-disciplines, as well as the educational ideals embedded.


Assuntos
Medicina Bucal , Faculdades de Medicina , Pequim , Currículo , Docentes , Humanos
8.
Wei Sheng Yan Jiu ; 50(5): 722-727, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34749863

RESUMO

OBJECTIVE: To understand the physical activity and regular exercise status and influencing factors of people with high risk of chronic diseases among Beijing residents, and to provide science basis for health education strategies and intervention measures. METHODS: 13 200 participants aged 18-79 were selected by stratified cluster sampling method for questionnaire survey in 2017.3448 participants without hypertension, diabetes and dyslipidemia met the criteria of high risk population. The metabolic equivalent of physical activity was calculated by referring to the summary of physical activity in the United States and the global physical activity questionnaire. RESULTS: 1794 male(52.0%) and 1654 female(48.0%) are included in this study. 862(25.0%) are 18-29 years old, 778(22.6%) are 30-39 years old, 640(18.6%) are 40-49 years old, 709(20.6%) are 50-59 years old, and 193(13.3%) are 60-79 years old. 684 participants(18.6%) are low physical activity level, 1480 participants(42.9%) are medium level and 1284 respondents(37.2%) are high level. The rate of never exercising is 60.2%. Multivariate analysis shows female(OR=1.32, 95%CI 1.11-1.55), aged 40-49(OR=1.34, 95%CI 1.04-1.72) and aged 50-59(OR=1.76, 95%CI 1.36-2.28) participants are likely to have high level physical activity. Participants with high education level(OR=0.78, 95%CI 0.66-0.93) and insufficient intake of fruits and vegetables(OR=0.73, 95%CI 0.64-0.84) are likely to have low physical activity level. Female(OR=1.46, 95%CI 1.22-1.76), participants with insufficient intake of fruits and vegetables(OR=1.44, 95%CI 1.24-1.69) are likely never to exercise. Participants with high education level(OR=0.46, 95%CI 0.38-0.55), high school education(OR=0.63, 95%CI 0.53-0.75), no job(OR=0.67, 95%CI 0.56-0.81) are likely to exercise. CONCLUSION: The population with high risk of chronic diseases in Beijing City was lack of physical activity. Gender, age, education level, fruit and vegetable intake are the influencing factors of physical activity level, while gender, fruit and vegetable intake, education level, marriage, employment and fruit and vegetable intake are the influencing factors of exercise.


Assuntos
Dieta , Verduras , Adolescente , Adulto , Idoso , Pequim/epidemiologia , Doença Crônica , Exercício Físico , Frutas , Humanos , Pessoa de Meia-Idade , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-34639832

RESUMO

The COVID-19 has caused a serious impact on the global economy, and all countries are in a predicament of fighting the epidemic and recovering their economies. Aiming to discuss the impact of the COVID-19 on the economic resilience of urban agglomerations, the economic data of each quarter from June 2019 to September 2020 of the Beijing-Tianjin-Hebei Urban Agglomeration are selected, and the economic development index (EDI) is calculated based on the entropy method. Combining the fundamental conditions of urban agglomerations and industrial policies during the COVID-19, urban economic resilience is discussed by the changing trend of the economic development index (EDI) and dividing into resistance and restoration. The results show that: (1) The economic development level of the urban agglomeration has been affected by the epidemic and has changed significantly. The change of endogenous power is the main cause of change; (2) During the outbreak of the COVID-19, the economic resilience of the Beijing-Tianjin-Hebei urban agglomeration shows four different development types: high resistance and restoration, high resistance but low restoration, low resistance but high restoration, low resistance and restoration cities; (3) High resistance but low restoration, low resistance but high restoration, and low resistance and restoration cities influence each other, but the relationship between cities is mainly dependent; (4) The economic restoration within the urban agglomeration forms a synergy, which promotes the economic recovery and development of the urban agglomeration during the recovery period of the COVID-19. Urban agglomerations should enhance the combined effect of resistance and increase the impact of high resistance and restoration cities on surrounding cities in the future.


Assuntos
COVID-19 , Epidemias , Pequim/epidemiologia , China/epidemiologia , Cidades , Surtos de Doenças , Humanos , Percepção , SARS-CoV-2
10.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(10): 993-999, 2021 Oct 24.
Artigo em Chinês | MEDLINE | ID: mdl-34674437

RESUMO

Objective: Explore the usage of anti-hypertension drugs and the rationality of hypertension prescription among the primary health centers in Dongcheng District, Beijing. Method: This cross-sectional and retrospective study was applied to analyze the hypertension prescriptions from the 8 community health centers in Dongcheng District. The anatomical, therapeutic and chemical classification (ATC) codes were used to determine the drug category. ATC information was used to filter data containing antihypertensive drugs, and group the number and proportion of ATC categories. The type of drug was judged by its generic name. According to the diagnosis information in the prescription, the prescription containing the Western medicine diagnosis of hypertension was screened out. The comorbidities of hypertension in the study included 7 types of diseases including diabetes, chronic kidney disease, coronary heart disease, heart failure, atrial fibrillation, stroke, and dyslipidemia. The analysis of prescription rationality included rationality of combination medication, rationality of drug dosage and rationality of drug price. The agreed daily dose (DDD) method was used to analyze the rationality of drug dosage. The drug utilization index (DUI) was used as a quantitative indicator to estimate the rationality of medication, and overdose was expressed by DUI>1. The reasonableness of the drug price was judged based on the price of the drug and whether it was a drug in the "4+7" plan. Results: A total of 658 140 prescriptions were extracted as the final data set, involving 7 categories and 60 commonly used anti-hypertensive drugs, and the corresponding cost of medication was ï¿¥96.58 million. Drugs were prescribed according to comorbidities, and the choice followed the international guidelines. Calcium channel blockers (CCB) were the most prescribed drugs in the prescriptions of patients with comorbidities, and α-adrenergic receptor antagonists were the least prescribed drugs. The proportion of diuretics prescribed in hypertensive patients complicating with heart failure was 21.17% (505/2 385), which was much higher than that of patients complicating with other comorbidities (P<0.05). The proportion of diuretics prescribed in hypertension patients complicating with dyslipidemia was lower than that of patients with other comorbidities (2 639 (0.94%), P<0.05), and ß-blockers (BB) or angiotensin Ⅱreceptor blockers (ARB) were more likely to be selected (BB: 59 348 (21.08%), ARB: 51 356 (18.24%))in these patients. The proportion of BB in prescriptions for hypertension patients with chronic kidney disease was lower than that of patients with other comorbidities (P<0.05). The proportion of BB in prescriptions for hypertension patients with coronary heart disease was higher than that of other comorbidities (P<0.05). Hypertension patients with atrial fibrillation or stroke accounted for a higher proportion of CCB prescriptions (P<0.05). Single antihypertensive drug prescriptions accounted for the highest proportion, 61.19% (402 745/658 140). Two-combination prescriptions accounted for the highest proportion of combination prescriptions, 72.19% (184 392/255 395). CCB based two-combination prescriptions accounted for the highest proportion, 122 350(66.36%). ARB-based tri-combination prescriptions accounted for the highest proportion, 48 915(89.50%),followed by CCB based tri-combination prescriptions (44 732(81.85%)).There were 2 174 (0.33%) prescriptions with unreasonable combination therapies and DUI>1 were found in 48 out of 60 commonly used drugs. In all possible antihypertensive drugs, only 40.92% (109 227/266 993)followed the "4+7" plan. Conclusions: The anti-hypertensive agents from these prescriptions in the primary health centers are diverse, and the choice is generally complied with the guidelines, but some unreasonable situations existed, especially on the combined anti-hypertensive medication, overdose, and"4+7"plan is not followed completely.


Assuntos
Anti-Hipertensivos , Hipertensão , Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Pequim/epidemiologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Centros Comunitários de Saúde , Estudos Transversais , Humanos , Hipertensão/tratamento farmacológico , Prescrições , Estudos Retrospectivos
11.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3487-3496, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676709

RESUMO

Forests in Beijing exhibit vulnerability to increasing stress of extreme drought in recent years. To investigate the drought tolerance of different tree species, we chose three tree species (Larix principis-rupprechtii, Pinus tabuliformis, and Quercus wutaishanica) from the forest of Dongling Mountain in Beijing and used dendroecological method to analyze the relationship between radial growth and climate, as well as their resistance and resilience to extreme drought events. Our results showed that the radial growth of L. principis-rupprechtii and P. tabuliformis was significantly negatively correlated with monthly mean temperature from May to June, but that of Q. wutaishanica was significantly negatively correlated with monthly mean temperature only in May. The radial growth of L. principis-rupprechtii was significantly positively correlated with monthly mean precipitation in June, monthly mean relative humidity from May to June and August to September. The radial growth of P. tabuliformis was significantly positively correlated with monthly mean precipitation and monthly mean relative humidity from June to August. The radial growth of Q. wutaishanica was significantly positively correlated with monthly mean precipitation in February and May, and monthly mean relative humidity in May. The radial growth of all the three species was significantly positively correlated with monthly mean SPEI (standardized precipitation evapotranspiration index) from May to July. L. principis-rupprechtii was least drought tolerant, as indicated by the greatest growth reduction (46.6%-69.6%), lowest resistance (0.534, 0.304, 0.530) and resilience (0.686, 0.570, 0.753) during the three extreme drought events occurred in the 1994, 2001-2002, and 2007. In contrast, tree growth of Q. wutaishanica showed the highest drought resistance in 2007, whereas no significant differences were observed between other two species. Extreme drought events caused by continuous high temperature and reduced precipitation during the growing season accounted for the reduction in tree radial growth. The various physiological and ecological strategies of tree species were the possible reasons for the difference in drought tolerance. Our results could provide a basis for the selection of suitable afforestation tree species and the formulation of forest protection mea-sures to maintain forest ecosystem functions and services under the background of undergoing climate change.


Assuntos
Secas , Ecossistema , Pequim , China , Mudança Climática
12.
Neuron ; 109(19): 3022-3024, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34619082

RESUMO

In this Neuron Q&A, Xiang Yu talks about the stress and anxiety brought to the lab by the pandemic, the new opportunities for teaching and scientific conferences it created, the value of the individual, and the social responsibility of science for humanity and society to shape a brighter future.


Assuntos
Neurociências/tendências , Pequim , COVID-19 , China , História do Século XXI , Pandemias , Apoio à Pesquisa como Assunto
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(10): 1209-1213, 2021 Oct 06.
Artigo em Chinês | MEDLINE | ID: mdl-34706506

RESUMO

Objective: To establish the norm of the Chinese version of Karitane Parenting Confidence Scale (KPCS) in urban areas of China. Methods: From August to December 2017, the parents of 2 216 children (<36 months old) were selected from 15 cities (Beijing, Lianyungang, Hangzhou, Chengdu, Xi'an, Guangzhou, Changsha, Jinan, Guiyang, Ningbo, Dalian, Qinhuangdao, Maanshan, Chongqing and Wuhan) in 14 provinces by stratified random sampling. The general demographic characteristics and parents' parenting confidence were collected by a self-made questionnaire and KPCS Chinese version. The percentile norm was established. P3, P10 and P25 were used as the criteria to define the degree of lack of parenting confidence. Results: The age of mothers was (30.67±4.29). The age of the father was (32.50±4.99) years old. There were 726 (32.76%), 759 (34.25%) and 731 (32.99%) infants in 6-12, 12-23 and 24-35 months old groups. The total scores of P50, P25, P10 and P3 of KPCS (Chinese version) of infant parents in urban areas in China were 41, 38, 33, and 29 respectively. When the scores of parents were 34-37, 30-33, and ≤ 29, they were judged as mild, moderate, and severe lack of parenting confidence. There was no significant difference in the Chinese version of KPCS between parents of different age groups and parents of different gender (χ²=3.53, P=0.171; χ²=1.41, P=0.236). Each factor score≤P3 is defined as the boundary score, and the corresponding boundary scores of "parenting" "support" and "competence" were 13, 9, and 5 respectively. Conclusion: The Chinese version of KPCS can be used to assess the parenting confidence of infants in urban areas of China. It can used as one of the bases for scientific and objective evaluation of the parenting status of families.


Assuntos
Mães , Poder Familiar , Adulto , Pequim , Criança , China , Feminino , Humanos , Lactente , Inquéritos e Questionários
14.
Sheng Wu Gong Cheng Xue Bao ; 37(10): 3663-3674, 2021 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-34708618

RESUMO

Aquatic plants and the epiphytic microorganisms are important contributors to the purification of constructed wetlands. Taking the dragon-shaped water system of Beijing Olympic Park as a model, this study analyzed the structure and function of the microbial communities reside the sediment, the water body and the rhizosphere and phyllosphere of three submerged plants-Vallisneria natans, Myriophyllum verticillatum, and Potamogeton pectinatus using high-throughput sequencing technology. The results showed that the microbial diversity from the highest to the lowest were samples from sediment, plant rhizosphere, plant phyllosphere and water. The microbial diversity of plant phyllosphere samples were significantly higher than those of the water body. LEfSe analysis showed that different habitats enriched different microbial groups. The sediments mainly enriched anaerobic microbes, while the water body and the phyllosphere of plants mainly enriched aerobic microbes, and the rhizosphere of plants had the both. Functional prediction analysis showed that the abundance of denitrification marker genes in phyllosphere samples was higher than that in samples from rhizosphere, sediment and water body, and the abundance of denitrification marker genes in phyllosphere samples of M. verticillatum and P. pectinatus was higher than that of V. natans. This study could serve as a guidance for the selection of submerged plants and functional microorganisms for constructed wetlands.


Assuntos
Hydrocharitaceae , Microbiota , Pequim , Rizosfera , Água
15.
Huan Jing Ke Xue ; 42(11): 5109-5121, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708950

RESUMO

To control the spread of the 2019 novel coronavirus(COVID-19), China imposed rigorous restrictions, which resulted in great reductions in pollutant emissions. However, two heavy haze pollution episodes still occurred in Beijing. In this study, we use the air pollutants, aerosol number concentration, and meteorological elements data in Beijing, combined with the HYSPLIT model, to calculate the potential source contribution factor(PSCF) and concentration weight trajectory(CWT), and analyze the characteristics of evolution and potential source apportionment of atmospheric pollutants during the two episodes. The COVID-19 lockdown restrictions had great impacts on the diurnal variations of PM2.5 and black carbon(BC), while small impacts on the diurnal variations of CO, NO2, SO2, and O3. The primary pollutant was PM2.5 during the two haze pollution episodes, and the haze1 episode was mainly local pollution, while haze 2 was mainly local and external transportation pollution. The spectrum of aerosol number concentration was unimodal under different processes, with the peak located at 0.3 µm. During the haze episodes, the number concentration in the size range of 0.2-0.5 µm increased 3.3-13.6 times that of the clean days. The mass concentration contributions of BCliquid to BC in different processes were 64.8%-85.1%. This mass concentration of BCliquid ranked in the order of haze 1(5.04 µg·m-3) >haze 1(3.20 µg·m-3) >clean day(before COVID-19) (2.31 µg·m-3) >clean day(COVID-19) (0.76 µg·m-3). The characteristics of PSCF and CWT distribution of PM2.5 and BC were different in different processes. The PSCF high value areas of PM2.5 on the clean day(before COVID-19) and the clean day(COVID-19) were mainly distributed in the southwest and western of Beijing, and the weight concentration exceeded 30 µg·m-3. The PSCF high value areas of PM2.5 during haze 1 and haze 2 were mainly distributed in Beijing and its surrounding areas and southwestern, when the weight concentration exceeded 90 µg·m-3. The PSCF high value areas of BC were mainly distributed in Beijing and its surrounding areas on clean days(before COVID-19), clean days(COVID-19) and haze 1, with weighted concentrations exceeding 2.4, 0.9 and, 4.5 µg·m-3, respectively. The PSCF high value areas of BC on haze 2 was distributed in the southwest of Beijing, and the weight concentration exceeded 5 µg·m-3.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Ambientais , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise , SARS-CoV-2 , Estações do Ano
16.
Huan Jing Ke Xue ; 42(11): 5275-5283, 2021 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-34708966

RESUMO

It has been confirmed that microplastics widely exist in the natural environment, causing potential harm to organisms and humans. An investigation into the occurrence of microplastics is helpful to understand the level of pollution of microplastics in urban rivers and sediments. In this study, eight sampling points of water samples and three of sediments samples were placed along the North Canal and Huaihe River in Beijing, to compare the composition and distribution characteristics of the abundance, particle size, color, shape, and species of microplastics. The results showed that the abundance of microplastics in the water and sediments of the North Canal were(1941±201)-(8155±1781) n·m-3(n refers to the number of microplastics) and (120±11)-(268±31) n·kg-1, respectively. The average abundance of microplastics in the water of the North Canal was 4160 n·m-3. Compared with the North Canal, the pollution degree of microplastics in the Huaihe River was lower with an average abundance of 2357 n·m-3. Furthermore, the abundance of microplastics in the water and sediments in the upper reaches of the North Canal was higher than that in the lower reaches. No significant difference of microplastics distribution was observed in the water of the Huaihe River on the whole; however, there was a marked difference in abundance between the two distant locations. The main particle size range of microplastics at all site points was<300 µm, and mostly white/transparent(50.75%-83.91%); the main shape were fragments(50.00%-95.08%) and fibers(3.86%-30.00%). Polyurethane(PU) and ethylene vinyl acetate(EVA) were two main plastic species found at all sites. Microplastics in the water and sediments of the North Canal might have originated from urban construction and development, while the surrounding villages might have only affected the abundance of microplastics in the Huaihe River.


Assuntos
Microplásticos , Poluentes Químicos da Água , Pequim , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Plásticos , Rios , Água , Poluentes Químicos da Água/análise
17.
Front Public Health ; 9: 765087, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34708021

RESUMO

This research studies the development of distribution networks for the last mile distribution for cross-border E-business based on a vision of fourth party logistics (4PL) in smart cities in emerging markets in response to COVID-19. This research analyzes the distribution centers of distribution companies in Beijing city using fuzzy cluster analysis as a case study of smart cities. The location decision for distribution centers to serve cross-border E-business is further analyzed by considering the local conditions of the distribution centers. The solutions to the location decisions for distribution centers in different cases are further visualized by 2-mode networks. The key nodes in the distribution network of the last mile for cross-border E-business are further studied based on fourth-party logistics by a immune algorithm. Cross-border E-business value creation based on the development of distribution networks using fourth-party logistics is further discussed. The location distribution of key nodes can spread from the downtown district to suburban areas as the coverage of the distribution network is expanded. This research can help managers and decision makers address the last mile distribution for cross-border E-business in smart cities in emerging markets based on a vision of fourth-party logistics in response to COVID-19.


Assuntos
COVID-19 , Algoritmos , Pequim , Cidades , Humanos , SARS-CoV-2
18.
Ying Yong Sheng Tai Xue Bao ; 32(8): 2895-2905, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34664463

RESUMO

Based on the MODIS NDVI data from 2000 to 2018, we estimated the fractional vegetation cover (FVC) using the dimidiate pixel model and analyzed the spatiotemporal characteristics of FVC in the Beijing-Tianjin sand source region (BTSSR). The geographical detector model was used to estimate the impacts of natural and human factors on FVC spatial distribution at the regional scale. The results showed that the FVC of the BBTSR showed an increasing trend from 2000 to 2018, with an annual growth rate of 0.013·(10 a)-1 and a vegetation increase rate of 8.2%. The area with high FVC was concentrated in the Yanshan Mountain water source protection area, followed by the pastoral transitional zone desertified land control area and the Otindag sandy land area. The area with poor FVC was concentrated in the northern arid grassland area. The explanatory power of driving factors to FVC varied across different regions. Among the natural factors, annual precipitation was the main driving factor for the spatial distribution of FVC in the northern arid grassland area, the Otindag sandy land area and the Yanshan Mountain water source protection area. Slope was the main driving factor for the spatial distribution of FVC in the pastoral transitional zone desertified land control area. Among different human activities, the number of large livestock at the year-end was the main driving factor controlling the spatial distribution of FVC in the northern arid grassland area and the pastoral transitional zone desertified land control area, while population density was the main driving factor controlling the spatial distribution of FVC in the Otindag sandy land area and the Yanshan Mountain water source protection area. There were regional differences in the influen-ce of other factors on FVC spatial distribution. The results of the interaction detector showed that the two-factor interactions were mainly the double-synergy and nonlinear synergy. The interaction of human activities with annual precipitation and slope could more fully explain the spatial variations of FVC. The range of suitable vegetation growth identified by the risk detector was the area with annual precipitation of 316.4-486.0 mm, average relative humidity of 48.4%-57.6%, and average annual temperature of 2.5-7.9 ℃, while other driving factors were different in different zones.


Assuntos
Ecossistema , Areia , Pequim , China , Atividades Humanas , Humanos
19.
BMC Health Serv Res ; 21(1): 1045, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34600531

RESUMO

BACKGROUND: To analyse the changes in curative care expenditure (CCE) associated with noncommunicable diseases (NCDs) before and after the Beijing healthcare reform, thus providing a reference for the healthcare system. METHODS: A total of 60 medical institutions were selected using multistage stratified cluster random sampling in Beijing, China. The records of approximately 100 million outpatients with NCDs in 2016-2018 were extracted. System of Health Accounts 2011 (SHA2011) was used to estimate the CCE. The segmented regression model was established to observe both the instant change and the slope change of intervention in interrupted time series analysis (ITSA). The study was conducted from December 2019 to May 2020 in Beijing, China. RESULTS: From SHA2011, we found that the CCE for outpatients with NCDs in Beijing were 58.59, 61.46 and 71.96 billion RMB in 2016, 2017 and 2018, respectively. The CCE continued to rise at all hospital levels, namely, tertiary, secondary, and community-level hospitals. However, the proportion of CCE in tertiary hospitals decreased. From ITSA, we can also conclude that the CCE showed a significant increasing trend change at the three hospital levels after the intervention. The drug proportion showed a significant decreasing trend change in secondary and tertiary hospitals. CONCLUSIONS: Beijing healthcare reform does have an impact on the CCE of NCDs.


Assuntos
Gastos em Saúde , Doenças não Transmissíveis , Pequim/epidemiologia , Reforma dos Serviços de Saúde , Humanos , Análise de Séries Temporais Interrompida , Doenças não Transmissíveis/epidemiologia , Doenças não Transmissíveis/terapia , Pacientes Ambulatoriais , Centros de Atenção Terciária
20.
J Environ Sci (China) ; 109: 57-65, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34607674

RESUMO

Improving our understanding of air pollutant emissions from the asphalt industry is critical for the development and implementation of pollution control policies. In this study, the spatial distribution of potential maximum emissions of volatile organic compounds (VOCs) in the complete life cycle of asphalt mixtures, as well as the particulate matter (PM), asphalt fume, nonmethane hydrocarbons (NMHCs), VOCs, and benzoapyrene (BaP) emissions from typical processes (e.g., asphalt and concrete mixing stations, asphalt heating boilers, and asphalt storage tanks) in asphalt mixing plants, were determined in Beijing in 2017. The results indicated that the potential maximum emissions of VOCs in the complete life cycle of asphalt mixtures were 18,001 ton, with a large contribution from the districts of Daxing, Changping, and Tongzhou. The total emissions of PM, asphalt fume, NMHC, VOCs, and BaP from asphalt mixing plants were 3.1, 12.6, 3.1, 23.5, and 1.9 × 10-3 ton, respectively. The emissions of PM from asphalt and concrete mixing stations contributed the most to the total emissions. The asphalt storage tank was the dominant emission source of VOCs, accounting for 96.1% of the total VOCs emissions in asphalt mixing plants, followed by asphalt heating boilers. The districts of Daxing, Changping, and Shunyi were the dominant regions for the emissions of PM, asphalt fume, NMHC, and BaP, while the districts of Shunyi, Tongzhou, and Changping contributed the most emissions of VOCs.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Pequim , China , Monitoramento Ambiental , Hidrocarbonetos , Compostos Orgânicos Voláteis/análise
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