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1.
Front Public Health ; 11: 1008378, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36935705

RESUMO

Since the end of 2019, the sudden outbreak of COVID-19 has challenged the emergency governance systems of various countries. As the cornerstone of national governance, China's community emergency governance mainly adopts top-down organizational mobilization and rapid response, which is typical abnormal governance. In responding to major public health events, China's national system has developed certain advantages in some respects. However, the current pandemic is still serious in many places, and new mutant strains are constantly appearing. Some drawbacks of such system and mechanism are gradually emerging. In the process of preventing and controlling the pandemic, China's urban communities have continuously improved the joint mechanism, and played the role of multiple principals in collaborative and co-governance. The current work of pandemic prevention and control has entered a period of normalization. What is the collaborative mechanism of multiple principals (Subdistrict headquarter, Community committee, Owners' committee, Community hospital, Local police station, Property management company, etc.) in urban communities participating in emergencies and how to seek ways to further improve the mechanism? Therefore, taking the community practice and actions in Guangzhou, China as an example, the present study employed a qualitative design, proposed to better community emergency governance mechanisms from the aspects of preparedness, response, communication and recovery, so as to provide a reference for other grassroots organizations.


Assuntos
COVID-19 , Saúde Pública , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle , Pesquisa Qualitativa , China/epidemiologia
2.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(6): 598-603, 2023 Jan 06.
Artigo em Chinês | MEDLINE | ID: mdl-36642899

RESUMO

OBJECTIVE: To investigate the prevalence and influencing factors of Blastocystis hominis infection among children with diarrhea under five years of age in Guangzhou City. METHODS: Children with diarrhea under 5 years of age admitted to Guangzhou Children's hospital, Guangzhou Maternity and Child Healthcare Hospital and Guangzhou Women and Children's Medical Center during the period between January 1 and December 31, 2020, were enrolled. Participants' demographics, living environments and health status were collected using questionnaire surveys. Stool samples were collected from participants and nucleic acid was extracted. B. hominis infection was identified using PCR assay and sequence alignment, and the factors affecting B. hominis infection among children with diarrhea under 5 years of age were identified using univariate analysis and multivariate logistic regression analysis. RESULTS: A total of 684 children with diarrhea under 5 years of age were enrolled, including 468 male children and 216 female children, with a mean age of (1.79 ± 1.12) years. The overall prevalence of B. hominis infection was 4.97% [34/684, 95% confidential interval (CI): (3.59%, 6.86%)] among participants, and there was no significant difference in the prevalence of B. hominis infection between children with chronic [7.52% (20/266), 95% CI: (4.92%, 11.33%)] and acute diarrhea [3.35% (14/418), 95% CI: (2.01%, 5.54%)] (χ2 = 5.983, P = 0.014). Multivariate logistic regression analysis identified keeping pet [odds ratio (OR) = 6.298, 95% CI: (2.711, 14.633)], drinking non-tap water [OR = 4.522, 95% CI: (1.769, 11.561)], lactose intolerance [OR = 4.221, 95% CI: (1.043, 17.087)], antibiotic use [OR = 0.125, 95% CI: (0.017, 0.944)] and chronic diarrhea [OR = 2.172, 95% CI: (1.018, 4.637)] as factors affecting B. hominis infection among children with diarrhea under 5 years of age in Guangzhou City. CONCLUSIONS: B. hominis infections is detected in children with diarrhea under five years of age in Guangzhou City. Improving home environments and pet-keeping hygiene is recommended to reduce the likelihood of B. hominis infection among children.


Assuntos
Infecções por Blastocystis , Blastocystis hominis , Gravidez , Humanos , Masculino , Feminino , Criança , Lactente , Pré-Escolar , Infecções por Blastocystis/epidemiologia , Fezes , Cidades , Diarreia/epidemiologia , Prevalência
3.
Toxics ; 11(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36668780

RESUMO

Fish size can heavily impact the bioaccumulation of metals, but it was rarely applied to screen out the fish with low health risk for consuming. Given the widespread metals contamination of angling fish, the angling fish collected from Guangzhou, China, were taken as an example in this study. The screening length and weight were detailed in accordance with the investigation of metals contamination among angling fish. Importantly, the feasibility of size screening on mitigating the health risk of angling fish was evaluated. The results revealed that the concentration of Cr and As were relatively high and beyond the maximum residue limit (MRL) in some fish. The mean pollution index (Pi) of As, Cr, and Pb were beyond 0.2, suggesting the widespread minor contamination. The total metal pollution index (MPI) manifested Oreochroms mossambcus was the most contaminated. The target hazard quotient (THQ) of Cr, As, and Hg were relatively higher, but the higher probability of THQ > 1 indicated the health risk should be dominantly from As. The highest TTHQ suggested the highest risk of Oreochroms mossambcus. Regression analysis determined the fish of THQ < 1 should be more likely centralized in the size that is beyond 13.7 cm and 45.0 g for adults and 19.8 cm and 127.9 g for children. Significantly reducing THQ among these screened fish confirmed their effect on the degrading health risk of metals; particularly, the children's THQ returned below 1. The commonly contaminated Oreochroms mossambcus was further excluded to remove the screened fish with THQ > 1; the further decrease in THQ confirmed that the exclusion of a contaminated species could improve the effect of size screening.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-953836

RESUMO

Objective To investigate the prevalence and influencing factors of Blastocystis hominis infection among children with diarrhea under five years of age in Guangzhou City. Methods Children with diarrhea under 5 years of age admitted to Guangzhou Children’s hospital, Guangzhou Maternity and Child Healthcare Hospital and Guangzhou Women and Children’s Medical Center during the period between January 1 and December 31, 2020, were enrolled. Participants’ demographics, living environments and health status were collected using questionnaire surveys. Stool samples were collected from participants and nucleic acid was extracted. B. hominis infection was identified using PCR assay and sequence alignment, and the factors affecting B. hominis infection among children with diarrhea under 5 years of age were identified using univariate analysis and multivariate logistic regression analysis. Results A total of 684 children with diarrhea under 5 years of age were enrolled, including 468 male children and 216 female children, with a mean age of (1.79 ± 1.12) years. The overall prevalence of B. hominis infection was 4.97% [34/684, 95% confidential interval (CI): (3.59%, 6.86%)] among participants, and there was no significant difference in the prevalence of B. hominis infection between children with chronic [7.52% (20/266), 95% CI: (4.92%, 11.33%)] and acute diarrhea [3.35% (14/418), 95% CI: (2.01%, 5.54%)] (χ2 = 5.983, P = 0.014). Multivariate logistic regression analysis identified keeping pet [odds ratio (OR) = 6.298, 95% CI: (2.711, 14.633)], drinking non-tap water [OR = 4.522, 95% CI: (1.769, 11.561)], lactose intolerance [OR = 4.221, 95% CI: (1.043, 17.087)], antibiotic use [OR = 0.125, 95% CI: (0.017, 0.944)] and chronic diarrhea [OR = 2.172, 95% CI: (1.018, 4.637)] as factors affecting B. hominis infection among children with diarrhea under 5 years of age in Guangzhou City. Conclusions B. hominis infections is detected in children with diarrhea under five years of age in Guangzhou City. Improving home environments and pet-keeping hygiene is recommended to reduce the likelihood of B. hominis infection among children.

5.
One Health ; 13: 100273, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34179329

RESUMO

Wenzhou mammarenavirus (WENV) is a zoonotic pathogen newly discovered in east and southeast Asia. WENV has been found in wild rodent animals around the world while its standing is barely understood in Guangzhou city, where is known as a region of outbreak hotspot for zoonotic emerging infectious diseases. To investigate the prevalence and genomic characteristics of mammarenavirus in Guangzhou City, lung tissue samples from wild rodent species were collected from five districts of Guangzhou City in the year 2015 and 2016. The viral RNA was extracted and then subjected to mammarenavirus-specific PCR. The result revealed approximately 1.0% (3/306) nucleic acid positivity for lung tissue samples obtained from three rodent species: Mus musculus, Rattus flavipectus, and Rattus norvegicus. Viral metagenomic sequencing of three samples was then carried out and two full segment L and three full segment S sequences were obtained. Phylogenetics analysis indicated the sequences of the new mammarenavirus strain have 76.2% - 94.4% similarity to known WENV encoded genes, with the highest similarity to the WENV 9-24 strain. Population structure analysis grouped all known WENV into seven lineages, and this WENV Guangzhou strain was grouped with WENV 9-24 as well. Though the seroprevalence result was not available, our data provides the first nucleic acid evidence of circulating WENV in Guangzhou city, and it suggested WENV had a broader host tropism than previously known.

6.
Huan Jing Ke Xue ; 42(2): 653-662, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742859

RESUMO

Cadmium (Cd) pollution poses a threat to human health, and research on Cd bioavailability as well as its ecological risk assessment can help prevent and mitigate Cd hazards. The enrichment characteristics and variability of Cd were investigated in sea-land interaction soil fractions and the associated environmental and ecological risks were evaluated using the accumulation index (Igeo), potential ecological hazard index (Er), and risk assessment coding (RAC). The results showed that:① The Cd content of miscellaneous fill material was typically lower than 0.3 mg·kg-1 and that of plain full was higher than 0.3 mg·kg-1. The Cd content of marine sediment was significantly higher than that of continental sediments, averaging 0.36 and 0.10 mg·kg-1, respectively. The concentration of Cd in marine sediments buried at shallow depths (<5 m) was generally higher than at greater depths (>5 m). ② There was a moderate correlation between Cd and CEC in artificial fill (Q4ml; correlation coefficient=0.52, P<0.05). There was a weak correlation between Cd and organic matter in the marine sediments (correlation coefficient=0.49, P<0.05). Total cadmium and the physical and chemical properties of soil had a significant influence on the fraction of soil cadmium. ③ The Igeo of artificially fill and marine sediment was dominated by the relationship 1 < Igeo < 2, which indicated a moderate level of pollution. The Er of artificial fill and marine sediment was mainly 80 < Er < 160, indicating a high potential ecological hazard. Soil acid-extractable Cd accounted for more than 50% of the total Cd in each drill hole, which generally indicated a very high potential ecological risk. These results provide a basis for environmental and agricultural decision-making and provide theoretical guidance for soil pollution investigations and remediation.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Disponibilidade Biológica , Cádmio/análise , China , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Metais Pesados/análise , Medição de Risco , Rios , Solo , Poluentes Químicos da Água/análise
7.
BMC Public Health ; 20(1): 1190, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736615

RESUMO

BACKGROUND: Great growth inequalities between urban and rural areas have been reported in China over the past years. By examining urban/rural inequalities in physical growth among children < 7 years old over the past three decades from 1985 to 2015 in Guangzhou, we analyzed altering trends of anthropometric data in children and their association with economic development during the period of rapid urbanization in Guangzhou. METHODS: The height, body weight and nutrition status of children under 7 years old were obtained from two successive cross-sectional surveys and one health surveillance system. Student's t-test, Spearman's rank-order correlation and polynomial regression were used to assess the difference in physical growth between children in urban and rural areas and the association between socioeconomic index and secular growth changes. RESULTS: A height and weight difference was found between urban and rural children aged 0-6 years during the first two decades of our research (1985-2005), which gradually narrowed in both sex groups over time. By the end of 2015, elder boys (age group ≥5 year) and girls (age group ≥4 year) in rural areas were taller than their counterparts in urban areas (p < 0.05).The same trend could be witnessed in the weight of children aged 6 years, with a - 1.30 kg difference (P = 0.03) for boys, and a - 0.05 difference (P = 0.82) for girls. When GDP increased, the gap in boys' weight-for-age z-score (WAZ from 0.25 to 0.01) and height-for-age z-score (HAZ from 0.55 to 0.03) between urban and rural areas diminished, and disappeared when the GDP per capita (USD) approached 25,000. In either urban or rural areas, the urbanization rate and GDP were positively associated with the prevalence of obesity (all R > 0.90 with P < 0.05) and negatively correlated with the prevalence of stunted growth (all R < -0.87 with P < 0.05). CONCLUSION: Growth inequalities gradually decreased with economic development and urbanization, while new challenges such as obesity emerged. To eliminate health problems due to catch-up growth among rural children, comprehensive intervention programs for early child growth should be promoted in rural areas.


Assuntos
Transtornos do Crescimento , Estado Nutricional , Obesidade Infantil , Urbanização , Antropometria , Povo Asiático , Peso Corporal , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Desenvolvimento Econômico , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prevalência , População Rural/tendências , População Urbana
8.
J Clin Lab Anal ; 34(9): e23419, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32537759

RESUMO

BACKGROUND: To detect the serum antibodies against respiratory viruses and atypical pathogens in adults with community-acquired pneumonia (CAP) in Guangzhou City (Guangdong province, China). METHODS: A retrospective study was carried out with samples from 685 adults who were admitted with CAP and 108 non-CAP control patients. Atypical pathogens and respiratory viruses in serum were detected using the Pneumoslide IgM test from Vircell, Spain. All patients were divided into 6 groups according to age: 18-24, 25-44, 45-59, 60-74, 75-89, and >90. RESULTS: The total positive rate of CAP was 35.4%, which was highest in the 18-24 age group (P < .05). The highest positive rate, 17.11%, was observed for Mycoplasma pneumoniae (MP). The mean age of MP-infected patients was higher than that of the controls (P < .05). The positive rates for influenza B (INFB), Legionella pneumophila (LP1), Coxiella burnetii (COX), influenza A (INFA), parainfluenza virus (PIV), respiratory syncytial virus (RSV), Chlamydophila pneumoniae (CP), and adenovirus (ADV) were 5.56%, 3.07%, 2.63%, 2.34%, 1.90%, 1.61, 0.88%, and 0.29%, respectively. There were 4.37% of patients with CAP having multiple infections. The main symptoms observed in the 685 CAP patients were cough and sputum production, in 78.4% and 67.4%. Fever was followed by 54% of CAP patients. Dyspnea (39.1%), anorexia (36.8%), increased thirst (26.7%), chills (18.7), headache (14.6%), and nausea (13.1%) were also frequently observed in the CAP patients. CONCLUSIONS: MP infection was the most common in adult CAP patients in Guangzhou City with the highest positive rate in the 18-24 age groups.


Assuntos
Anticorpos Antivirais/sangue , Infecções Comunitárias Adquiridas , Imunoglobulina M/sangue , Pneumonia Viral , Vírus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/imunologia , Infecções Comunitárias Adquiridas/virologia , Feminino , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Estudos Retrospectivos , Adulto Jovem
9.
Environ Pollut ; 262: 114311, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32179228

RESUMO

In this study, 45 indoor dust samples and four particulate samples from air-conditioner filters were collected from four different indoor environments in Guangzhou, China, and the concentration and composition of organophosphate tri-esters (OPEs) and organophosphate di-esters (Di-OPs) were determined. Eight of the 10 target OPEs were detected in indoor dust at different detection frequencies (DFs), with tris(2-chloroisopropyl) phosphate and tris(2-chloroethyl) phosphate being the main components. Seven target Di-OPs were detected at different DFs, with diphenyl phosphate being the dominant compound. The total OPEs (∑8 OPEs) and total Di-OPs (∑7 Di-OPs) concentrations varied from 726 to 39,312 ng/g and 68.8-14,766 ng/g, respectively. The ∑8 OPEs concentrations in instrumental houses were significantly higher (p < 0.001) than in three other indoor environments. The varying strengths of the correlation between Di-OPs and their respective parent OPEs was suggestive of their emission sources (e.g., direct application, impurities in OPE formulas, and OPE degradation). The hazard index (HI) values of individual OPEs in residential house were lower than 1, the results suggested a limited human health risk from individual OPEs. However, the total HI value (∑HIs) of OPEs was approximately 1 based on a high exposure scenario and suggested a low risk for toddlers.


Assuntos
Poeira/análise , Retardadores de Chama/análise , Pré-Escolar , China , Monitoramento Ambiental , Ésteres/análise , Humanos , Organofosfatos/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-32110940

RESUMO

Epidemiological features of esophageal cancer (EC), as well as their associations withpotential influencing factors in a city, have seldom been seldom explored on a fine scale. The ECdeath cases in Guangzhou city during 2012-2017 were collected to describe the epidemiologicalcharacteristics such as EC mortality rate (ECMR) and health-seeking behaviors of deaths. Potentialinfluencing factors, including socioeconomic conditions (population density, gross domesticproduct density), medical resources, and ageing degree were also gathered for exploring theirrelationships with the epidemiological characteristics of EC. A total of 2,409 EC deaths werereported during 2012-2017 in Guangzhou with an age-standardized ECMR of 3.18/105. Theprevalence of EC in Guangzhou was spatially featured and was divided into three regions withobvious differentiated ECMR (ECMR of 6.41/105 in region A, ECMR of 5.51/105 in region B, ECMRof 2.56/105 in region C). The street/town-level ECMR was spatially clustered in Guangzhou city,especially two clusters of streets/towns with high ECMR were highlighted in region A and Brespectively. Meanwhile, demographic features including gender gap, death age, temporal intervalbetween diagnosis and death, health-seeking behaviors were remarkably different among the threeregions. Moreover, health-seeking behaviors (e.g., the proportion of hospital deaths) of the ECdeaths were obviously influenced by medical institution occupancy rate and socioeconomicconditions at street/town level. In addition, the street/town-level ECMR was significantly associatedwith ageing degree across Guangzhou city (r = 0.466, p < 0.01), especially in region A (r = 0.565, p <0.01). In contrast, the ECMR in region B was closely related to population density (r = -0.524, p <0.01) and gross domestic product density (r = -0.511, p < 0.01) when the ageing degree was controlled,while these associations were weak in region C. The epidemiological characteristics of EC inGuangzhou city were spatially featured and potentially associated with socioeconomic conditions,medical resources and ageing degree on a fine scale across Guangzhou city. This study couldprovide scientific basis for local authorities to implement more targeted EC interventions.


Assuntos
Neoplasias Esofágicas , Aceitação pelo Paciente de Cuidados de Saúde , Fatores Socioeconômicos , Envelhecimento , China/epidemiologia , Cidades , Neoplasias Esofágicas/epidemiologia , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Densidade Demográfica
11.
Zhonghua Yi Shi Za Zhi ; 49(2): 89-94, 2019 Mar 28.
Artigo em Chinês | MEDLINE | ID: mdl-31137157

RESUMO

According to all the reports about "eliminating the four pests" in Nanfang Daily and Guangzhou Daily between 1949 and 1959, this paper reviews the formation and development of "eliminating four pests" movement in Guangzhou. The movement started from 1949, and its first stage ended in 1952. The focus of the movement was to improve the appearance and environment of Guangzhou. From 1952 to 1956, the Patriotic Public Health Campaign started, and reached its climax around 1958, yet the movement has moved from pragmatism to radicalism. In the 10 years of "eliminating the four pests" , the movement has greatly improved the public health in Guangzhou and played a positive role in improving the physical health of the people in Guangzhou. However, excessive activities such as wiping out sparrows have also caused serious ecological disasters and poor harvests.

12.
Artigo em Inglês | MEDLINE | ID: mdl-30400330

RESUMO

Urban disaster risk assessment is the most basic and important part of urban safety development. Conducting disaster prevention and mitigation on the basis of urban disaster risk assessment requires an understanding of the relationship between the city and the natural environment. This enhances the city's ability to withstand various types of disasters and achieves the development of a safe city. Based on a review of the existing literature, we propose a fuzzy comprehensive evaluation method for urban multi-disaster risk assessment. The multi-disaster risk assessment method includes the identification and screening of urban disasters, the assessment of individual disaster risk, and integrated urban disaster risks, the division of urban comprehensive disaster risks into several risk levels, and the determination of coping strategies. Taking Guangzhou (China) as an example, we determined the major disaster risks faced by Guangzhou, assessed the risks of individual disasters, and finally obtained the results of the comprehensive disaster risk of Guangzhou. Second, we analyzed the relationship between the disaster risk assessment and urban safety development, and proposed countermeasures and recommendations for the development of different disaster risk levels.


Assuntos
Planejamento de Cidades/métodos , Desastres , Meio Ambiente , Medição de Risco , China , Cidades , Desastres/prevenção & controle , Pesquisa Empírica , Modelos Teóricos
13.
Huan Jing Ke Xue ; 39(6): 2528-2537, 2018 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965607

RESUMO

Atmospheric volatile organic compounds (VOCs) were measured in an urban area of Guangzhou on July 2016 using an on-line gas chromatography mass spectrometry/fire ion detector. Seventy-three VOCs were detected with an average concentration of (118.83±79.40) µg·m-3, a maximum concentration of 492.42 µg·m-3, and a minimum concentration of 10.54 µg·m-3 during the period. The peak value of the TVOC concentration appeared at about 07:00 in the morning, indicating that motor vehicle pollution had a significant contribution at the site. The minimum value appeared at about 14:00 in the afternoon, related to photochemical losses. High concentrations were also observed from 21:00 to 24:00, which was probably related to pollution emissions and boundary layer compression. Source analysis by PMF showed that the site was mainly affected by five VOC sources: vehicle exhaust, solvent use, fuel loss at fuel stations, plant emissions, and cooking exhaust, the contributions of which were 29.79%, 26.61%, 24.86%, 9.91%, and 8.84%, respectively. Vehicle exhaust was the largest source of VOCs during the daytime, while the contribution of plant emissions increased significantly at noon. The contribution of solvent uses and fuel loss at fuel stations rose during the night and became the main source of VOCs until early morning.

14.
Sci Total Environ ; 635: 26-34, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29660724

RESUMO

Land urbanization can affect carbon sequestration. In this study, the relationships between land urbanization and carbon sequestration of urban vegetation were studied for Guangzhou, China. The methodology was based on land use data from Thematic Mapper (TM) imagery, MODIS13Q1 data, and climate data, and the improved Carnegie-Ames-Stanford approach (CASA) model and linear system models were employed. Characteristics such as the amount of expansion, spatial agglomeration, spatial expansion intensity, and spatial growth of built-up land were analyzed, and the influence of land urbanization (built-up land expansion) on carbon sequestration of urban vegetation was elucidated by a temporal sequential cooperativity analysis. The main results were as follows. (1) Land urbanization had a clear influence on carbon sequestration of urban vegetation in Guangzhou, and the proportion and spatial agglomeration of built-up land showed significant negative correlations with this carbon sequestration; the correlation coefficients were -0.443 and -0.537, respectively, in 2014. (2) The spatial expansion intensity and spatial growth of built-up land showed small correlations with carbon sequestration, and the correlations from 2000 to 2005 were relatively larger than those at other times; this was because the built-up land expansion speed was the fastest during this period. (3) The temporal sequential cooperativity analysis revealed that carbon was lost as natural surfaces were transformed to artificial surfaces, and land urbanization effects on carbon sequestration showed no significant temporal lag. Carbon sequestration of urban vegetation in the city could be improved by adding urban green spaces; however, this would likely take some time as the system recovers.

15.
Environ Monit Assess ; 188(1): 54, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26700678

RESUMO

There are widespread concerns about urban sprawl in China. In response, modeling and assessing urban expansion and subsequent land use and land cover (LULC) changes have become important approaches to support decisions about appropriate development and land resource use. Guangzhou, a major metropolitan city in South China, has experienced rapid urbanization and great economic growth in the past few decades. This study applied a series of Landsat images to assess the urban expansion and subsequent LULC changes over 35 years, from 1979 to 2013. From start to end, urban expansion increased by 1512.24 km(2) with an annual growth rate of 11.25 %. There were four stages of urban growth: low rates from 1979 to 1990, increased rates from 1990 to 2001, high rates from 2001 to 2009, and steady increased rates from 2009 to 2013. There were also three different urban growth types in these different stages: edge-expansion growth, infilling growth, and spontaneous growth. Other land cover, such as cropland, forest, and mosaics of cropland and natural vegetation, were severely impacted as a result. To analyze these changes, we used landscape metrics to characterize the changes in the spatial patterns across the Guangzhou landscape and the impacts of urban growth on other types of land cover. The significant changes in LULC and urban expansion were highly correlated with economic development, population growth, technical progress, policy elements, and other similar indexes.


Assuntos
Monitoramento Ambiental/métodos , Urbanização/tendências , China , Cidades , Conservação dos Recursos Naturais , Políticas , Crescimento Demográfico
16.
Sensors (Basel) ; 9(1): 503-18, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22389613

RESUMO

The Interferometric Point Target Analysis (IPTA) technique and Advanced Synthetic Aperture Radar (ASAR) images acquired over Hong Kong from 2007-2008 were used to detect ground deformation in the urban area of Guangzhou city in South China. A ground deformation rate map with scattered distribution of point targets shows the maximum subsidence (rise) rate as high as -26 to -20 mma(-1) (16-21 mma(-1)), implying that the study area is an active zone for ground deformation. Based on the point target map, a contour ground deformation rate map is generated. The map shows three major subsidence zones located in the middle-west, the east, and the southwest of the study area, respectively. All the six ground collapse accidents that occurred in 2007-2008 fall within the subsidence zones, qualitatively validating the IPTA results. Ground subsidence and geological conditions on Datansha Island are examined. The results indicate that the local geological conditions, such as limestone Karst geomorphology as well as silt layers characterized by high water content, high void ratio, high compressibility, low bearing capacity and low shear strength, and underground engineering projects are responsible for ground subsidence and ground collapse accidents occurred there.

17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-532391

RESUMO

The construction of a harmonious physician-patient relationship.The perfection of healthcare system by local government and construction of systematic ethics serve as the premise.The enhancement of physician-patient relationship management by hospitals,the improvement of medical service,medical ethics instruction,and the systematic construction of physician-patient communication are key steps.The reform of medical treatment assessment,setting up of the third-party mediation institution,and the strengthening construction of public opinion direction are important conditions.

18.
Microbiology ; (12)1992.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-685001

RESUMO

One year survey on the concentrations and monthly or seasonal variations of airborne microbe in Guangzhou city were analysed and studied with JWL-IIB airborne microbial sampler. The results showed that the yearly average airborne microbe content of outdoor was 2, 298 cfu/m3, and that of indoor was 1,792 cfu/m3 in Guangzhou city. The monthly variation range of outdoor airborne microbe was from 1,073 to 4,096 cfu/m3, the highest content was 4,096 cfu/m3 in March, and the lowest content was 1,073 cfu/m3 in October. The outdoor airborne bacteria and fungi counts were the highest in spring, next in summer, lower in winter and the lowest in autumn in the four seasons . The yearly average concentrations of outdoor airborne microbe at the Garbage compression station, the business walk street, the key traffic route, the residential area, the industrial district and the garden were 4, 573, 3, 835, 1, 580, 1,413, 1, 197 and 1, 187 cfu/m3respectively; and Ones of indoor at the key traffic route, the tourist three star-route hotel and the subway station were 2,511, 1,699and 1,167 cfu/m3 respectively . The study on airborne microbe can be used for the research of health prevention and environment control measures in Guangzhou .

19.
China Pharmacy ; (12)1991.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-517669

RESUMO

OBJECTIVE:To analyze the trend of costs of various drugs consumed in hospitals of Guangzhou METHODS:The data were derived from the Hospital Purchasing of Drug Information System in Guangzhou from 1997 to 2000 The expense of each drug was calculated at the price of that year RESULTS:The annual increasing rates of drug expenses in 1998,1999 and 2000 were 17 01%,24 49%,23 11% respectively CONCLUSION:It is a matter of great urgency to rationally use drugs,to eliminate the waste of resources and to lighten the patients'burden

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