RESUMO
OBJECTIVE: To study source apportionment of atmospheric PM10 (particle matter ≤ 10 µm in aerodynamic diameter) and PM2.5 (particle matter ≤ 2.5 µm in aerodynamic diameter) in Beijing,Urumqi and Qingdao, China. METHODS: The atmospheric particle samples of PM10 and PM2.5 collected from Beijing between May 17th and June 18th, 2005, from Urumqi between April 20th and June 1st, 2006 and from Qingdao between April 4th and May 15th, 2005, were detected to trace the source apportionment by factor analysis and enrichment factor methods. RESULTS: In Beijing, the source apportionment results derived from factor analysis model for PM10 were construction dust and soil sand dust (contributing rate of variance at 45.35%), industry dust, coal-combusted smoke and vehicle emissions (contributing rate at 31.83%), and biomass burning dust (13.57%). The main pollution element was Pb, while the content (median (minimum value-maximum value)was 0.216 (0.040-0.795) µg/m(3)) . As for PM2.5, the sources were construction dust and soil sand dust (38.86%), industry dust, coal-combusted smoke and vehicle emissions (25.73%), biomass burning dust (13.10%) and burning oil dust (11.92%). The main pollution element was Zn (0.365(0.126-0.808) µg/m(3)).In Urumqi, source apportionment results for PM10 were soil sand dust and coal-combusted dust(49.75%), industry dust, vehicle emissions and secondary particles dust (30.65%). The main characteristic pollution element was Cd (0.463(0.033-1.351) ng/m(3)). As for PM2.5, the sources were soil sand dust and coal-combusted dust (43.26%), secondary particles dust (22.29%), industry dust and vehicle emissions (20.50%). The main characteristic pollution element was As (14.599 (1.696-36.741) µg/m(3)).In Qingdao, source apportionment results for PM10 were construction dust (30.91%), vehicle emissions and industry dust (29.65%) and secondary particles dust (28.99%). The main characteristic pollution element was Pb (64.071 (5.846-346.831) µg/m(3)). As for PM2.5, the sources were secondary particles dust, industry dust and vehicle emissions (49.82%) and construction dust (33.71%). The main characteristic pollution element was Pb(57.340 (5.004-241.559) µg/m(3)).Enrichment factors of Zn, Pb, As and Cd in PM2.5 were higher than those in PM10 both in Beijing and Urumqi. CONCLUSION: The major sources of the atmospheric particles PM10 and PM2.5 in Beijing were cement dust from construction sites and sand dust from soil; while the major sources of those in Urumqi were pollution by smoke and sand dust from burning coal. The major sources of the atmospheric particles PM10 in Qingdao were cement dust from construction sites; however, the major sources of PM2.5 there were secondary particles dust, industry dust and vehicle emissions. According to our study, the heavy metal elements were likely to gather in PM2.5.
Assuntos
Poluentes Atmosféricos/análise , Cidades , Estações do Ano , China , Poeira/análise , Monitoramento Ambiental/métodos , Tamanho da Partícula , Emissões de Veículos/análiseRESUMO
OBJECTIVE: To investigate the job satisfaction and its influential factors in oil production workers. METHODS: 423 oil production workers were investigated using the Occupational Stress Instrument. RESULTS: The job satisfaction, job organization satisfaction, job itself satisfaction in the workers aged < 30 years old (45.69 +/- 10.98, 22.63 +/- 6.16, 23.07 +/- 5.39 respectively) were lower than those in workers aged > or = 30 years old (49.34 +/- 10.12, 24.60 +/- 5.40, 24.74 +/- 5.36 respectively) (P < 0.01). The job satisfaction in the groups of different service length was significantly different. The job satisfaction in the workers of service length 5-10 years was the lowest compared with those of service length < 5 years and > 10 years (P < 0.05). The gender, education, marriage did not show obvious influence on the job satisfaction. The relationship between psychological health, work locus of control, coping strategies, affective balance and social support showed a statistical significance difference (P < 0.01). Regression was analyzed by taking job satisfaction as strain and personal characters, occupational stress factors, coping as independent variables. Five variables entered regression equation. They were work locus of control, affective balance, social support, psychological health and coping strategies. CONCLUSION: The job satisfaction of oil production workers is affected by multiple factors such as the age, work length and social support.
Assuntos
Indústrias Extrativas e de Processamento , Satisfação no Emprego , Adulto , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Petróleo , Inquéritos e Questionários , Adulto JovemRESUMO
OBJECTIVE: To investigate general states of the work locus of control and explore the relationship between work locus of control and occupational stress in oil workers. METHODS: 582 oil workers were investigated by using the General Questionnaire and Occupational Stress Measure Inventory. RESULTS: There were significant differences in WCLS score between two age groups (= 30 years old group and < 30 years old group) (t = 2.093, P = 0.037). Values of interpersonal relationship, person responsibility, promotion, participation, autonomy, task consistency, challenge, job satisfaction, mental health, self-esteem and coping strategies were higher in the group of internal locus of control; values of role ambiguity, working prospect, depression and social support were higher in the group of external locus of control (P < 0.05). Work locus of control had positive relation with role ambiguity, working prospect, depression, and social support, and negative with interpersonal relationship, promotion, participation, task consistency, challenge, job satisfaction, mental health, self-esteem and coping strategies. In the regression analysis, work locus of control was the major predictive factor of work satisfaction. CONCLUSION: Work locus of control is associated with many occupational stress factors. The group of extrinsic work locus of control experience more stress in oil workers.
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Controle Interno-Externo , Doenças Profissionais/psicologia , Petróleo , Estresse Psicológico , Adaptação Psicológica , Adulto , Feminino , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão , Inquéritos e QuestionáriosRESUMO
On the basis of the previous work for optimization of O,O-diethyl α-(substituted phenoxyacetoxy)alkylphosphonates, further extensive synthetic modifications were made to the substituents in alkylphosphonate and phenoxy moieties of the title compounds. New O,O-dimethyl α-(substituted phenoxyacetoxy)alkylphosphonates were synthesized as potential inhibitors of pyruvate dehydorogenase complex (PDHc). Their herbicidal activity and efficacy in vitro against PDHc were examined. Some of these compounds exhibited significant herbicidal activity and were demonstrated to be effective inhibitors of PDHc from three different plants. The structure-activity relationships of these compounds including previously reported analogous compounds were studied by examining their herbicidal activities. Both inhibitory potency against PDHc and herbicidal activity of title compounds could be increased greatly by optimizing substituent groups of the title compounds. O,O-Dimethyl α-(2,4-dichlorophenoxyacetoxy)ethylphosphonate (I-5), which acted as a competitive inhibitor of PDHc with much higher inhibitory potency against PDHc from Pisum sativum and Phaseolus radiatus than from Oryza sativa , was found to be the most effective compound against broadleaf weeds and showed potential utility as herbicide.
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Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Herbicidas/síntese química , Herbicidas/farmacologia , Proteínas de Plantas/antagonistas & inibidores , Complexo Piruvato Desidrogenase/antagonistas & inibidores , Inibidores Enzimáticos/química , Herbicidas/química , Estrutura Molecular , Proteínas de Plantas/metabolismo , Plantas/efeitos dos fármacos , Plantas/enzimologia , Complexo Piruvato Desidrogenase/metabolismo , Relação Estrutura-AtividadeRESUMO
OBJECTIVE: To investigate the prevalence and subtypes of influenza viruses in Liaoning regions from November 1999 to March 2005. METHODS: Influenza virus was isolated by embryonated eggs together with cell culture and subtypes, identified by HI test. RESULTS: During the study in 1999 - 2005, a total number of 2713 swab specimens were collected in different cities in Liaoning regions in which 188 strains were identified for influenza viruses with an average rate as 7.0%. A total number of 1466 swab specimens were collected by both Centers for Disease Control and Prevention in Dalian city and Liaoning province, and 167 strains were identified positive with an average rate of 11.4%. Influenza A3, A1 and B/Yamagata all appeared before March 2002 which were predominant strains. However, since then Influenza A1 has never appeared again in Liaoning regions and B showed some changes, from Yamagata to Victoria, the characteristics on the prevalence of influenza appeared only in the period of November to February. CONCLUSION: It was meaningful to analyze the surveillance data of influenza in different years in Liaoning regions in order to better understand the characteristics of influenza and the shifting of subtype.