Dissertationen zum Thema „Adverse effects of light pollution“
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Novák, Filip. „Využití jasového analyzátoru pro kvantifikaci umělého světla v nočním prostředí“. Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442543.
Der volle Inhalt der QuelleBarros, Ana Raquel Gonçalves de. „Marcadores biológicos de tabagismo : determinação de cutoff points“. Master's thesis, Faculdade de Ciências Médicas. Universidade Nova de Lisboa, 2011. http://hdl.handle.net/10362/5914.
Der volle Inhalt der QuelleLam, Sau-kei Angel, und 林秀琪. „Systematic review on the adverse effects of traffic related air pollution on respiratory health in children“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/193836.
Der volle Inhalt der Quellepublished_or_final_version
Public Health
Master
Master of Public Health
Wiegleb, Edström Desiree. „Long-wave ultraviolet radiation (UVA1) and visible light : therapeutic and adverse effects in human skin /“. Stockholm : [Karolinska Univ. Press], 2001. http://diss.kib.ki.se/2001/91-7349-003-2/.
Der volle Inhalt der QuelleAlmeida, Nisha. „Measures of maternal tobacco smoke exposure and foetal growth“. Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112375.
Der volle Inhalt der QuelleMethods. Subjects were 444 term controls drawn from 5,337 participants of a multi-centre nested case-control study of preterm birth in Montreal. Maternal hair, collected after delivery, was measured for average nicotine and cotinine concentration across the pregnancy, assuming hair growth of 1 cm/month. The BW for GA z-score used Canadian population-based standards. Multiple linear regression was used to assess effects on the z-score, after controlling for potential confounders.
Results. In regression models for maternal active smoking analysis, the addition of hair nicotine to models containing either self-report or hair cotinine or both self-report and cotinine explained significantly more variance in the BW for GA z-score (p=0.009, p=0.017, and p=0.033, respectively). In maternal passive smoking analysis, no significant effect of ETS on BW for GA was found using hair biomarkers.
Conclusion. These results indicate that hair biomarkers are sensitive tools capable of predicting reductions in birthweight for maternal active smoking. The stronger results obtained for nicotine are reflective of the fact that hair nicotine is a better measure of maternal smoking, but it could also suggest that nicotine plays an aetiologic role in affecting foetal growth.
Olsson, David. „Adverse effects of exposure to air pollutants during fetal development and early life : with focus on pre-eclampsia, preterm delivery, and childhood asthma“. Doctoral thesis, Umeå universitet, Yrkes- och miljömedicin, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-93962.
Der volle Inhalt der QuelleVaartnou, Manivalde. „EPR investigation of free radicals in excised and attached leaves subjected to ozone and sulphur dioxide air pollution“. Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29444.
Der volle Inhalt der QuelleLand and Food Systems, Faculty of
Graduate
Iyer, Akshay B. „Let there be light... Characterizing the Effects of Adverse Lighting on Semantic Segmentation of Wound Images and Mitigation using a Deep Retinex Model“. Digital WPI, 2020. https://digitalcommons.wpi.edu/etd-theses/1368.
Der volle Inhalt der QuelleInostroza, Pedro Verfasser], Henner [Akademischer Betreuer] [Hollert und Werner [Akademischer Betreuer] Brack. „Organic micropollutants in freshwater ecosystems : pollution dynamic and adverse effects at population genetic level in a model freshwater population / Pedro Inostroza ; Henner Hollert, Werner Brack“. Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1157122396/34.
Der volle Inhalt der QuelleInostroza, Pedro [Verfasser], Henner [Akademischer Betreuer] Hollert und Werner [Akademischer Betreuer] Brack. „Organic micropollutants in freshwater ecosystems : pollution dynamic and adverse effects at population genetic level in a model freshwater population / Pedro Inostroza ; Henner Hollert, Werner Brack“. Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1157122396/34.
Der volle Inhalt der QuelleWatters, Jessica A. „The Effects of Ecological Light Pollution and Silhouette Height on the Nesting Densities of Caretta caretta in Broward County, Florida“. NSUWorks, 2007. http://nsuworks.nova.edu/occ_stuetd/101.
Der volle Inhalt der QuelleBernard, David P. „Impact of stream acidification on invertebrates : drift response to in situ experiments augmenting aluminum ion concentrations“. Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24478.
Der volle Inhalt der QuelleScience, Faculty of
Zoology, Department of
Graduate
Ackermann, Simone. „Environmental effects on the circadian systems of a diurnal ( rhabdomys dilectus) and noctural (micaelamys namaquensis) rodent species with specific reference to light pollution“. Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/77808.
Der volle Inhalt der QuelleDissertation (MSc)--University of Pretoria, 2019.
Zoology and Entomology
MSc
Unrestricted
Nilsson, Anders. „Novel Technique for Analysing Volatile Compounds in Indoor Dust : Application of Gas Chromatography – UV Spectrometry to the Study of Building-Related Illness“. Doctoral thesis, Linköping : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-5199.
Der volle Inhalt der QuelleWright, Elaine Frances. „The effect of ozone on horticultural crops important in the Fraser Valley of British Columbia“. Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28356.
Der volle Inhalt der QuelleLand and Food Systems, Faculty of
Graduate
Torricelli, André Augusto Miranda. „Efeitos de níveis elevados de poluição atmosférica na superfície ocular de controladores de tráfego e taxistas na cidade de São Paulo“. Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5149/tde-25092013-154010/.
Der volle Inhalt der QuellePurpose: To evaluate the effect of high levels of environmental air pollution on ocular surface of taxi drivers and traffic controllers of São Paulo, including the assessment of signs and symptoms, tear osmolarity assays, and goblet cells count from conjunctival impression cytology. To verify whether there is correlation between such findings as well as with nitrogen dioxide (NO2) levels and particulate matter smaller than 2.5 ?m (PM2.5) levels to which they were exposed. Methods: Taxi drivers and traffic controllers from São Paulo, Brazil were enrolled into the study. Mean individual levels of 24-hours exposure to nitrogen dioxide (NO2) and particulate matter smaller than 2.5 ?m (PM2.5) were assessed on 4 different occasions. On the first and third visits, subjects were submitted to clinical evaluations including the administration of the Ocular Surface Disease Index (OSDI) questionnaire, slit-lamp examination, estimation of tear breakup time (BUT), the Schirmer test, and vital staining of the cornea and conjunctiva. On the second and fourth visits, tear samples were collected from right eye for osmolarity assays, while conjunctival impression cytology was collected from left eye. To estimate the effect of the air pollutants (NO2 and PM2.5) on the endpoints throughout the study generalized estimating equations were adopted. Correlations between NO2 or PM2.5 levels, clinical findings, tear osmolarity and goblet cells density were investigated. Results: Seventy-one taxi drivers and traffic controllers, aged from 31 to 65, were enrolled in the study. Air pollution exposure levels remained very high, as noted by the mean PM2.5 levels of 40 ?m/m3 and the mean NO2 levels constantly above of 100 ?m/m3 during the period of study. Few symptoms were reported in the OSDI questionnaire with score (mean ± standard deviation) of 9.18 ± 6.81 e 8.27 ± 11.92 at the first and third visit, respectively. BUT was low with mean values of 5 seconds, while Schirmer test showed mean values above 10 mm with wide variability. The corneal vital staining score with fluorescein was inferior to 4 in all but one eye (0.7%) with a score of 5. The conjunctival vital staining score with lissamine green was considered normal in 124 eyes (87.3%) in the first visit and in 120 eyes (84.5%) in the third visit. The results of the osmolarity assay at the second and fourth visits were within normal limits with mean ± standard deviation of 298.56 ± 23.19 and 303.72 ± 23.52 mOsmol/kg, respectively. Regarding goblet cells density, the mean ± standard deviation values were 464.42 ± 256.66 and 407.82 ± 269.18 cells/mm2 on bulbar conjunctiva and 735.52 ± 295.87 and 707.92 ± 272.51 cells/mm2 on the tarsal conjunctiva, at the second and fourth visit, respectively. A significant and negative correlation was found between PM2.5 and tear film osmolarity (p<0.05). xxiii An increase of 10 ?m/m3 in PM2.5 levels was associated with 10.9 mOsmol/Kg decrease in tear osmolarity. There also was a negative correlation, though not statistically significant, between NO2 and tear osmolarity No correlation was found between conjunctival goblet cells count and NO2 or PM2.5 levels as well as no correlation was found between OSDI questionnaire or clinical findings and air pollution exposure. Conclusion: Exposure to high levels of air pollution reduces tear film osmolarity and influences tear film stability, although it is not associated with symptoms and other clinical signs in individual without ocular disease. Alterations on tear film osmolarity combined to goblet cells density modification may be part of an adaptive ocular surface response to air pollution exposure
Novaes, Priscila. „Efeitos da poluição atmosférica na superfície ocular“. Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5149/tde-27022012-114920/.
Der volle Inhalt der QuelleThe purpose of this study was to assess the effects of different levels of ambient air pollution on the ocular surface, combining determinations of individual exposure with clinical and histological parameters. Methods: Stage 1: A total of 29 volunteers from two locations - São Paulo (n=13) and Divinolândia (n=16) were selected. We assessed mean individual levels of NO2 exposure for 7 days, using a passive sampler. Impression cytology samples were obtained from inferior tarsal conjunctiva. Goblet cell counts and NO2 exposure level were compared between the two groups, and between individual values. Stage 2: A total of 55 volunteers, who lived in São Paulo, were selected. The mean individual levels of nitrogen dioxide (NO2) exposure were assessed, as in Stage 1. All subjects answered the Ocular Symptom Disease Index (OSDI) and a symptoms inventory. Subsequently, subjects underwent Schirmer I test, biomicroscopy, vital staining and tear break-up time (TBUT) assessment. OSDI scores, symptoms frequency and clinical data were compared to individual NO2 exposure values by statistical analysis. Results: Stage 1: The NO2 exposure levels were 68% higher for individuals living in São Paulo (mean = 32.47, SD = ± 9.83) than for those living in Divinolândia (mean 19.33, SD ± 5.24) (p = 0,005). There was a steady increase in goblet cell counts, proportional to NO2 exposure (=0.566, p=0.001). Stage 2: There was a significant association between NO2 levels and OSDI scores (p<0.05), reported ocular irritation (p<0.05) and TBUT (p<0.05, = -0.316). Conclusions: An association between exposure to higher levels of air pollution, goblet cell hyperplasia, ocular discomfort symptoms and tear film instability was detected; indicating that there are clinical and histological effects of NO2 exposure, and that these measurements may be used as biomarkers of the adverse effects of air pollution on the ocular surface
Correia, Joya Emilie de Menezes. „Variações no pico de fluxo expiratório associadas à exposição à poluição atmosférica e sensibilização alérgica em crianças em São Paulo (SP)“. Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5137/tde-08102014-144649/.
Der volle Inhalt der QuelleThe health effects of air pollution range from lung function decrements to mortality. In the last 20 years, there has been an increase in the incidence of allergic respiratory diseases worldwide. Even though genetic factors play an important role, air pollution has been discussed as one of the factors responsible for this increase. The objective of this study was to investigate the effects of air pollution on peak expiratory flow of children who were sensitized and children who were not. Ninety-six children (9 to 11 years old) were followed from April to July, 2004 with daily measurements of peak expiratory flow. Blood samples were collected for IgE and total blood count. Skin prick test was done using common allergens: mites (Dermatophagoides pteronyssinus, Dermatophagoides farinae e Blomia tropicalis), dog (Canis familiaris), cat (Felis domesticus), cockroach (Periplaneta americana) and fungus (Aspergillus fumigatus, Alternaria alternata, Cladosporium herbarium, Chaetomium globosum, Mucor mucedo, Pullularia pullulans, Penicillium notatum). Daily hourly concentrations of all criteria pollutants, temperature and relative humidity were available for the entire period. Analysis was performed with the generalized estimated equations (GEE). A decrease in peak flow measurements was found to be associated mainly with PM10, NO2 and O3, considering different time lags (hours, previous day, moving average). The effects of the pollutants were not different among children with or without allergic sensitization
Matsumoto, Giselli Silva. „"Efeito da poluição atmosférica urbana da cidade de São Paulo nas células sangüíneas e no sistema cardiopulmonar. Estudo morfo-funcional em camundongos in vivo"“. Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-28122005-034256/.
Der volle Inhalt der QuelleObjective: verify if air pollution of São Paulo city induces alterations in blood and cardiopulmonary systems. MM: Balb/c mice were exposed during 7, 14, 21, 30 and 45 days to 3 chambers: Clean (control), Intermediate (PM only) and Dirty (external air). After exposure, animals were ventilated (FlexiVent) and collected lung mechanics data and blood, heart and lung. PM, CO, SO2 e NO2 were measured daily. Results: on day 21 and 45, coincidently to peak of pollutions, there was proximal airway resistance increase (45d p=0.012), leukocytosis (21d p < 0.001 and 45d p=0.039) and vasoconstriction of peribronchiolar arterioles (21d p=0.034) in animals of Dirty Chamber with no alterations of coronaries. Neither pollutants exceeded the standard limits
Lopes, Fernanda Degobbi Tenorio Quirino dos Santos. „O efeito da exposição a níveis ambientais de material particulado no desenvolvimento do enfisema pulmonar em camundongos“. Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5159/tde-24012008-125920/.
Der volle Inhalt der QuelleInhalation of particulate matter (PM) exacerbates a variety of pulmonary disorders, including COPD and asthma, but the specific effects of PM on the developing of emphysema are largely unknown. We investigated the effects of chronic exposure to ambient levels of PM on the development of emphysema and pulmonary remodeling in mice. Mice received either papain or normal saline and were kept for two months in two chambers in an area of high traffic density: one received ambient air and the other had filters for PM. We performed lung morphometry, measured the density of elastic and collagen fibers and studied the expression of matrix metalloproteinase-12 (MMP-12), macrophage MAC-2, 8-isoprostane and caspase 3. Lungs from papain-treated mice exposed to ambient air presented greater values of mean linear intercept than papain-treated mice kept in the chamber with filtered air (47.11±1.49 and 39.33±1.93 miu m, respectively, p=0.002). There was an increase in the density of collagen fibers and in the expression of 8- isoprostane in pulmonary tissue of papain-treated mice that remained in the chamber with ambient air (p<0.05 and p=0.002, respectively). There were no significant differences between these two groups in the amount of cells expressing MAC-2, MMP-12 and caspase-3. There were no significant differences in any of the parameters studied between saline-treated mice kept in the two chambers. We conclude that exposure to urban levels of PM worsens protease-induced emphysema and increases pulmonary remodeling. We suggest that an increase in oxidative stress induced by PM exposure influences this response.
Chiarelli, Paulo Sérgio. „Efeito da poluição do tráfego na pressão arterial dos agentes de trânsito em Santo André“. Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-23022010-131238/.
Der volle Inhalt der QuelleThe constant exposition to air pollution continues to cause the populations health problems, and its result an increase of morbidity and mortality by respiratory and cardiovascular diseases. This is a cross-sectional study which aims to assess the modifications in the systemic blood pressure and the pulse pressure in young male individuals, exposed to the traffic pollution in Santo André city, metropolitan region of the Greater São Paulo in Brazil. The hourly daily levels of air pollutants were obtained from the Technology Institute for the Environment and Sanitation of São Paulo State (CETESB), the information by temperature and precipitation was obtained from the National Meteorology Office (INMET). There has been carried out a descriptive analysis of all variables of the study. The linear equation model has been used, having as dependent variables the systolic blood pressure (SBP), the diastolic blood pressure (DBP) and the pulse pressure (PP), the air pollutants as independent variables, and as control variables the minimum temperature, precipitation, working period and day time. A number of 19 traffic agents in Santo André city have been analysed. The average age of the studied group was of 42.8 (sd = 5.2) years old, ranging from 32 to 51 years old. Concerning the BMI, we have got the information that the average of the studied group was of 25.2 (sd = 2.8), ranging from 19.2 to 29.4. It is observed that for an interquartile range increased in PM10 (34g/m3), the SBP increases in 1.35 mmHg (CI95%: 0.40; 2.30), the DBP increases in 1.35 mmHg (CI95%: 0.57; 2.13), and the PP increases in 1.35 mmHg (CI95%: 0.40; 2.30) at the exposure time. The traffic agents in Santo André city presented increase of SBP, DBP and PP with the exposure to PM10 and to O3. The traffic agents from Santo André presented higher arterial blood pressure and pulse pressure levels associated with the air pollution exposure in Santo André city
Soares, Sandra Regina Castro. „Efeito aterogênico da poluição atmosférica: associação aos anticorpos anti LDLox e anti peptídeo D da apoB e aos aspectos morfométricos e inflamatórios“. Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-29012007-171900/.
Der volle Inhalt der QuelleEpidemiologic studies have shown important relationship between atherogenic cardiovascular morbid-mortality and acute or chronic exposure to air pollution. We aim to study the atherogenic potential of São Paulo urban air pollution analyzing the plaque formation and its physiopathology through oxidative stress and auto-antibody production in a murine experimental model in vivo. We quantified the lipid deposit in the atherosclerotic plaque and its thickness by Image Analyzer, LDL oxidation in blood by TBARS and tissue by 8-isoprosthane, production of anti oxLDL and anti peptide D of apoB-100 antibodies by ELISA and macrophage activation through MAC2 staining. We analyzed three regions of the aorta: emergency, arch and descendent in 40 LDLR - / - knockout mice, male, 30 days old exposed to selective intoxication chambers with filters or not for particulate matter and toxic gases, during May to September 2004, when pollution did not overpass standard limits of air quality. Mice were divided in four groups: Filtered-Normal diet (FN), Filtered-enriched cholesterol diet (FEchol), Polluted-Normal diet (PN) and Polluted-enriched cholesterol diet (FEchol). Our results were: the highest amount of total cholesterol levels in FEchol and PEchol groups (p<0,05); the lowest triglycerides in PEchol mice (p<0,05); increment of oxLDL in blood only in PEchol animals; higher anti oxLDL and anti-peptide D antibodies in PN and PEchol than other groups (p<0,05); similar amounts of lipids in atherosclerotic plaque in Echol diet groups, but higher than mice submitted to Normal diet (p<0,05); PEchol mice presented the highest aorta thickness (p<0.05); oxidative stress showed similar results in both aortic regions in all groups; macrophage activation in descent region of the aorta showed that FEchol mice presented higher values than animals submitted to normal diet (p<0,05) and PEchol group reached higher values than PN animals (p<0,05); macrophage activation in the atherosclerotic necrotic core and plaque of the aortic arch showed similar pattern: FEchol higher than normal diet mice (p<0,05). We concluded that urban air pollution, even within standard limits of air quality, is able to potentate atherosclerosis progression.
Alemany, Adair Aparecida Santos. „Influência da dieta hipercolesterolêmica em camundongos knock-out LDLr -/- expostos as partículas ambientais concentradas sobre o sistema pulmonar“. Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-25092013-151131/.
Der volle Inhalt der QuelleEpidemiological and experimental data have shown adverse effects of gestational and post natal exposure to ambient particulate matter (PM) on the fetal and adult health. However, few studies addressed the fetal toxicity of gestational exposure to environmental air pollution as well as long-term adverse consequences of prenatal exposure on postnatal development and maturation of several organ systems. The aim of this study was to determine if prenatal and/or postnatal exposure to concentrated ambient particles influences lung development and pulmonary vascular response in an atherosclerosis susceptible mouse model (LDLr-/- knockout mice). LDLr-/- mice were exposed during the pregnancy to either filter (AF) or polluted air (CAP). After weaning period, pups were subdivided and new 4 groups formed according to gestational and continuous or not post natal exposure to air pollution. Reaching the age of 3 months these groups were again subdivided and a hypercholesterolemic (HC) diet introduced and a total of 8 groups were formed. Then the following parameters were analyzed: evaluation of the offspring outcomes, assessment of airway responsiveness, evaluation of cytokines in BALF, dosage of total cholesterol (TC) and triglycerides (TG) in the liver and pulmonary vascular response by immunohistochemistry. Results: Animals that received HC diet presented higher levels of cholesterol (p=0.002) when compared to those animals that received normal diet. Expression of IL-6 was only increased in the groups of mice exposed not exposed to particulate air pollution and that received the HC diet (p=0.01). Significant differences were also observed in vascular expression of immunomarkers in the lung endothelin (p=0.05); ENOS (p=0.04); IL1? (p=0.005); INOS (p=0.002); ISOP (p=0.001); NOX2 (0.01) e ICAM (0.04). Total lung volume was also different, there was an increase in those animals receiving a HC diet. In conclusion, the response of the lung development to gestational exposure to particulate air pollution can be evidenced later in life and act as a modulator factor for postnatal insults due to exposures to particulate air pollution and hypercholesterolemic diet in individual predisposed to atherosclerosis
Veras, Mariana Matera. „Efeitos da poluição do ar da cidade de São Paulo sobre o processo reprodutivo de camundongos com ênfase no desenvolvimento da placenta e cordão umbilical“. Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-31102008-125138/.
Der volle Inhalt der QuelleAir pollution is an important environmental health risk factor for many different gestational and reproductive negative outcomes. In this study we have investigated the effects of two different timing of exposure (before conception and during pregnancy) to urban ambient particulate matter on reproductive and pregnancy outcomes in mice. Using exposure chambers receiving filtered (F) and non-filtered (NF) we observed that exposed females presented changes in the length of estrus cycle, extended estrus and antral follicles number declined by 36% (P=0.04) in mice exposed to non filtered air (75±35.2) compared to mice exposed to filtered air(118.6 ±18.4). Our results further indicate a significant increase in time necessary to mating and decreased fertility and pregnancy indices (P=0.003) in NF couples. Mean postimplantation loss (PIL) rate was increased by 70% (P0.005) in the group exposed before and during pregnancy to non-filtered air when compared to the group exposed before and during pregnancy to filtered air. Fetal weight (FW) was significantly higher in group exposed during both periods to filtered air when compared to other groups exposed before and/or during pregnancy to non filtered air. FW and PIL mean rate were influenced by both pre-gestational (p<0.01) and gestational (p<0.01) period exposure. Maternal pre-gestational and the first stage of pregnancy exposure are critical to increased risk for low birth weight in mice. We also found that gestational exposure to non-filtered air was associated with reduced volumes, calibres and surface areas of maternal blood spaces and with greater fetal capillary surfaces and diffusive conductances of the placenta. Umbilical cord morphology was also altered. This study demonstrated that exposure to ambient levels of urban traffic generated particulate matter negatively affects different functions and stages of the reproductive process. Our results also indicate that maternal exposure to air pollution is linked to negative pregnancy outcomes even if maternal exposure occurs only before conception
Olmo, Neide Regina Simões. „Poluição atmosférica e exposição humana: a evolução científica epidemiológica e sua correlação com o ordenamento jurídico“. Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-24052011-162041/.
Der volle Inhalt der QuelleINTRODUCTION: Currently, there is no correlation between the fields of healthcare and law in Brazil regarding the adoption of public policies aimed at preventing/avoiding, remedying or minimizing the adverse effects of atmospheric pollution on human health. OBJECTIVE: The present study had the objective of demonstrating the increasingly eminent need for interaction between epidemiology and law, thereby revealing that these fields are not autonomous sciences but integrated instruments for use in seeking efficient public policies relating to atmospheric pollution caused by automotive vehicles. METHODS: We built up a systematic review of epidemiological studies relating to the effects of atmospheric pollution on human health, using the PubMed database and well-defined descriptors. The search results then underwent selection by three independent researchers with experience of this topic. A review of the national environmental legislation relating to atmospheric pollution was made, using official databases, including the CONAMA (National Environment Council) standards, and international documents relating to atmospheric emission standards were investigated. We conducted structured interviews with public policymakers in the environmental field, with a view to analyzing the opinions of representatives of this distinct segment of society regarding the matter in question. RESULT: Out of 2,530 studies initially selected, only 32 Brazilian and 112 foreign studies were considered to fit within the inclusion criteria established. Among the Brazilian studies, 27 showed that there were adverse effects on human health even at concentrations lower than what is legally permitted, and 18 discussed public policies in some manner. Among the foreign studies, 78 showed that there were adverse effects on human health even at concentrations lower than what is legally permitted, and 13 discussed public policies. The interviewees unanimously stated that there was a need to update the current emission standards and comply with the emissions timetable, and that there was inadequate understanding between the field of healthcare and the adoption of public policy measures. They showed that they were aware of the scientific research that had been conducted and were concerned about the data presented. CONCLUSION: We thus demonstrated that: there is a need for law and epidemiology to combine in order to draw up public guidelines; a need for the populations awareness to be raised, and for emission standards to be changed and the effective participation from public bodies within the policymaking and healthcare sectors. Identification, recognition and acceptance of the complexity and the research data are the cornerstones of the interface between the domains of science, society and politics
Matsuda, Monique. „Efeito da talidomida na expressão e síntese dos proteoheparans sulfato de superfície celular em linhagens de mieloma múltiplo“. Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5136/tde-19032010-122711/.
Der volle Inhalt der QuelleThe adverse effects of particle emissions produced by sugar cane burning represent a proble that affects ostly developing countries. Previous studies have shown that, during the burning period, there is an increase in respiratory hospital admissions and emergency room visits in communities surrounded by sugar cane plantations in rural cities of Brazil. However, until this date, nom previous studies have evaluated the effects on the ocular surface. The ai of the present work is to study the impact of the sugar cane burning on the ocular surface of cane workers and the people at the city of Tatuí, near the burning crops. Twenty two healthy sugar cane workers and nineteen volunteers fro Tatuí region located at the State of Sao Paulo, Brazil, were recruited to the study. Measure ents of the average concentrations of particulate atter 2.5um, temperature and humidity were done during the burning and non burning periods. Concurrently, histological and clinical assessments of the ocular surface such as, inferior tarsal impression cytology, tear film break-up time, Schirmer´s I test, fluorescein and rose bengal staining, biomicroscopy and eye irritation symptoms were evaluated during the two periods. PM2.5 exposure levels in the crops during the activity of burnt cane cutting were 3.5 fold higher than the suggest limit of 25ug/m3 proposed by governmental regulation. On ocular assessments, we observed that the average of periodic acid Schiff (PAS)positive areas of sugar cane workers samples were lower during the burning (mean 57%,SD 6.8) than the non burning period (mean 64.3%,SD 12;p=0.014) and the downtown volunteers samples (mean 63.9%,SD 6.8;p=0.009). A non linear regression model reveals a strong relationship between average PAS positive areas and years working in sugar cane harvesting. We noticed an increase in PAS positive areas as long as the years accumulated in sugar cane harvesting labor during non burning period (r=0.99,p=0.015). Schirmer test t reveals impairment at the values across the years of labour in sugar cane harvesting observed during the burning period (r=0.99,p=0.026). Mean TBUT values of sugar cane workers during the burning period (mean 6.48s; SD 3.47)were lower than non burning period (mean 10.16s;SD 7.79) and than TBUT of the volunteers of downtown (mean 8.6s,SD 4.6;p<0.05). There were no statistically differences among the groups for the other ocular variables. Our results suggest that seasonal exposition of higher concentrations of emissions generated by sugar cane burning ay cause toxic effects on the mucosal epithelium and affect tear film stability that ay leave underlying ocular epithelium less protected to har ful agents. On the other hand, chronic occupational exposure to sugar cane emissions during harvest ay induce an adaptive response of ocular epithelium associated with an increase of mucus density in order to compensate loss of goblet cells every year during burning period. In conclusion, these findings reinforce the importance for further investigations to better understanding the consequences of air pollution on the ocular surface and suggest procedures to protect ocular surface during this period.
Matsuda, Monique. „Efeitos das emissões geradas pela queima dos canaviais sobre a superfície ocular“. Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-12012011-172239/.
Der volle Inhalt der QuelleThe adverse effects of particle emissions produced by sugar cane burning represent a problem that affects mostly developing countries. Previous studies have shown that, during the burning period, there is an increase in respiratory hospital admissions and emergency room visits in communities surrounded by sugar cane plantations in rural cities of Brazil. However, until this date, no previous studies have evaluated the effects on the ocular surface. The aim of the present work is to study the impact of the sugar cane burning on the ocular surface of cane workers and the people at the city of Tatuí, near the burning crops. Twenty-two healthy sugar cane workers and nineteen volunteers from Tatuí region located at the State of Sao Paulo, Brazil, were recruited to the study. Measurements of the average concentrations of particulate matter 2.5 Vm, temperature and humidity were done during the burning and non-burning periods. Concurrently, histological and clinical assessments of the ocular surface such as, inferior tarsal impression cytology, tear film break-up time, Schirmer´s I test, fluorescein and rose bengal staining, biomicroscopy and eye irritation symptoms were evaluated during the two periods. PM2.5 exposure levels in the crops during the activity of burnt cane cutting were 3.5-fold higher than the suggest limit of 25Vg/m3 proposed by governmental regulation. On ocular assessments, we observed that the average of periodic acid-Schiff (PAS) positive areas of sugar cane workers samples were lower during the burning (mean 57%, SD 6.8) than the non-burning period (mean 64.3%, SD 12; p=0.014) and the downtown volunteers samples (mean 63.9%, SD 6.8; p=0.009). A non-linear regression model reveals a strong relationship between average PAS positive areas and years working in sugar cane harvesting. We noticed an increase in PAS positive areas as long as the years accumulated in sugar cane harvesting labor during non-burning period (r=0.99, p=0.015). Schirmer test t reveals impairment at the values across the years of labour in sugar cane harvesting observed during the burning period (r=0.99, p=0.026). Mean TBUT values of sugar cane workers during the burning period (mean 6.48s; SD 3.47) were lower than non-burning period (mean 10.16s; SD 7.79) and than TBUT of the volunteers of downtown (mean 8.6s, SD 4.6; p<0.05). There were no statistically differences among the groups for the other ocular variables. Our results suggest that seasonal exposition of higher concentrations of emissions generated by sugar cane burning may cause toxic effects on the mucosal epithelium and affect tear film stability that may leave underlying ocular epithelium less protected to harmful agents. On the other hand, chronic occupational exposure to sugar cane emissions during harvest may induce an adaptive response of ocular epithelium associated with an increase of mucus density in order to compensate loss of goblet cells every year during burning period. In conclusion, these findings reinforce the importance for further investigations to better understanding the consequences of air pollution on the ocular surface and suggest procedures to protect ocular surface during this period.
Arantes, Petra de Mello Motta. „Efeitos pulmonares da fumaça de cigarro associada ao particulado de diesel exaurido (DEP) em camundongos“. Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5169/tde-15122015-111112/.
Der volle Inhalt der QuelleChronic obstructive pulmonary disease (COPD) is characterized by limitation of gas exchange and is considered a non-reversible, progressive disease and associated with an abnormal inflammatory response of the lungs to particles and harmful gases, with extrapulmonary symptoms. Cigarette smoke (CS) is the major cause, since 80% of COPD cases are associated with smoke. Also, the air pollution is considered a risk factor in the development, acceleration, exacerbation and mortality of COPD. Moreover, diesel exhaust particles (DEP) are a major source of traffic-related air pollution. Many studies have demonstrated the damaging effects of CS and air pollution on human health; however, few have related the association between the two factors. Considering a smoker in an urban area undergoes daily to this two exogenous agents simultaneously, we evaluated the effects of CS associated to DEP, from diesel-powered engines in the São Paulo city, on emphysema development at 1, 3 and 6 months. Mice were divided into fifteen groups: control (C); vehicle (V) (NaCl 0.9%); DEP (30?g DEP in 10ul NaCl 0.9%/day, 5 days/wk); CS (exposed to CS, 30 minutes/day, 5 days/wk); and CS+DEP. We evaluated respiratory mechanics; inflammatory cells in bronchoalveolar lavage fluid (BALF); mean linear intercept (Lm) and morphometry and remodeling: peribronchovascular edema, MMP-12, Mac-2, elastin and collagen-III. There was a significant increase in airway resistance in CS and CS+DEP compared to group V and DEP at 6 mo. We observed an increase in Lm after 6 mo in the CS, DEP and CS+DEP groups compared to group V. The total number of cells in BALF and macrophage showed an increase at 3 mo of CS exposure and at 6 mo of CS or DEP exposure. However, there was a decrease of the number of total cells at 6 mo in CS+DEP compared to V. Polimorphonuclear cells in airways were increased after 3 and 6 months mainly in the DEP and CS+DEP groups. Peribronchovascular edema was increased in the CS+DEP group after 1 mo, CS and DEP groups after 3 mo and CS and CS+DEP groups after 6 mo. Elastin, increased for the CS, DEP and CS+DEP groups and collagen III only for the CS+DEP group; and the density of MMP-12 positive cells in CS, DEP and CS+DEP, and Mac-2 in DEP, all after 6 months of exposure.Therefore, the onset of COPD, with enlargement of alveolar spaces, occurs after 6 mo of exposure independent of which exogenous particles were inhaled. However, we did not show an impairment in emphysema when animals received both CS+DEP inhalation. Analysis of cell profiles showed an increase in inflammatory cells after CS or DEP exposure, but on different pathways, while interaction of CS+DEP showed an additive effect that attenuated the inflammatory process after 6 mo and that intensively acted on remodeling mechanisms. Our study supports the additives effects of the interaction between CS and DEP, mimicking a smoker exposed to urban air pollution. And reaffirms that this complex interaction still demand more clarification and it is a great field of research in lung disease
Oliveira, Regiani Carvalho de. „Efeito da composição do material particulado fino, PM2,5 e residual oil fly ash (ROFA), como determinante do potencial mutagênico e tóxico celular: um estudo em bioensaios vegetais e animais“. Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-29012007-145939/.
Der volle Inhalt der QuelleThe association between atmospheric particulate matter (PM) and adverse human health effects have been consistently reported in epidemiological and experimental studies however, the ability to define the most important components involved in PM toxicity is hindered by its complex composition. In the present study we decided to further explore the effects of different atmospheric particles due to both source and composition, on the biologic system through 3 experiments. The mutagenicity and toxicity of urban PM2,5 of Sao Paulo, Brazil, from a bus strike day was evaluated by the TRAD-MN assay and inhibition of mitotic rate test of root tips Allium cepa. The frog palate was used to evaluate functional parameters (mucociliary transport ? MCT, ciliary beating frequency - CBF and potential difference ? PD) and morphometric data (epithelium tikness and mucus production) of the mucocliary apparatus exposed to ROFA from an a still plant, and to urban PM2,5. The comparative analysis of PM2,5 composition made by neutrons activation, fluorescence X-ray and gas cromatography/mass spectrometry showed decrease of trace elements, sulfur concentration (44,17%) and organics compounds (39,3%) in relation to the non strike day and was associated to coherent reduction in DNA damage. ROFA induced functional injury of the mucociliary apparatus (decrease of MCT and icrease of CBF) and the presence of antioxidants n-Propyl gallate and E vitamin protected against the mucociliary impairment induced by ROFA exposure. The comparative analysis between ROFA and PM2,5 composition showed that ROFA exhibited predominance of iron while PM2,5 showed heterogeneous composition presenting predominance of sulfur (37,594%±17,930%), iron (14,490%±6,489%) and silicon (13,142%±8,516%) and decrement of nickel (0,0336%±0,312%) and vanadium (0,260%±0,006%). We concluded that PM plays an important role in respiratory injury through oxidative stress and that adverse effects of PM on the biologic systems are strongly dependent on its composition.
Reis, Marcelo Moreno dos. „Poluição atmosférica e efeitos adversos na gravidez em um município industrializado no estado do Rio de Janeiro“. Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-08122009-184117/.
Der volle Inhalt der QuelleBACKGROUND: Several studies have shown the association between outdoor air pollution and adverse pregnancy outcomes, related to low birth weight (LBW), preterm birth and intrauterine grow restriction (IUGR). OBJECTIVES: To investigate the association between low birth weight and preterm delivery and maternal exposure to specific outdoor air contaminants, particulate matter (PM10), sulfur dioxide (SO2) and ozone (O3) in Volta Redonda, an industrialized city in the state of Rio de Janeiro, Brazil. METHODS: This population-based cohort study comprised all infants born to women resident in Volta Redonda, Rio de Janeiro, Brazil, in the period of 2003-2006. Birth data used in this retrospective study were obtained from the Information System on Live Births (SINASC) of Brazilian Ministry of Health. Exposure information was provided by air quality monitoring system operated by Environmental Agency for the State of Rio de Janeiro (FEEMA). Logistic and linear models were employed to assess the contribution of air pollution to low birth weight (LBW) and prematurity. RESULTS: The study covered 13660 births occurred from 1 January 2003 to 31 December 2006. The mean (SD) birth weight was 3162.2 g (561.8), and low birth weight represented 9.1% of all newborns. Prematurity was observed in 7.4% of all newborns. Adjusted relative risk for LBW showed that second and third trimesters maternal exposure to PM10 increased the risk for low birth weight, as well as exposure to O3 increased the risk for LBW in second and third trimesters. We observed a reduction in birth weight due to interquartile increase of O3 in third trimester of pregnancy. We also found dose response relationship between low birth weight and PM10 and O3 during the second and third trimester. In relation to preterm delivery we found an increased risk associated to maternal exposure to SO2 during all three trimesters, as well as we found dose relationships between prematurity and exposure to SO2 in each trimester. CONCLUSIONS: This study suggests that exposures to O3, SO2 and PM10, even below brazilian air quality standards, contribute to risks of low birth weight and preterm delivery, in the city of Volta Redonda/Brazil. The results highlight the need of revising air quality parameters to guarantee people health.
Rodrigues, Nilsa Regina Damaceno. „Medidas de indicadores de estresse oxidativo e de remodelamento cardíaco em camundongos expostos à poluição atmosférica ambiental durante o desenvolvimento embrionário e pós-natal“. Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-31052007-143719/.
Der volle Inhalt der QuelleI t is well known that air pollution exposure in São Paulo can elicit cardiovascular injuries in humans and experimental animals and that children and fetuses appear to be particularly vulnerable. However, the mechanisms involved in this cardiovascular damage are not well understood. It has been suggested that the oxidative stress generated by air pollution exposure can trigger tissue injury. There is evidence supporting the idea that injury caused by lipid peroxidation may be related to the causes of several cardiovascular diseases. The aim of this study was to investigate the effects of prenatal and postnatal exposure to urban air pollution on the myocardium lipid peroxidation levels of adult mice. Myocardium lipid peroxidation was determined by the TBA method and by the detection of 15-F2t-isoprostan by immunohistochemical technique. The animals were placed in two chambers: one received air that passed through an air filter (clean) and the second received ambient air (polluted), according to four different exposure procedures: 1) Clean (CC): prenatal and postnatal in the clean chamber (control group), 2) Polluted (PP): prenatal and posnatal in the polluted chamber, 3) Polluted-clean (PC): prenatal in the polluted and posnatal in the clean chamber and 4) Clean-polluted (CP): prenatal in the clean and posnatal in the polluted chamber. The concentration of of malondialdehyde (MDA, a indicator of lipid peroxidation) was higher in group PP compared to CC (p = 0.004) and to PC (p = 0.026), and was not different of group CP (p = 0.894). The values of MDA for groups PC and CP turned to be equal (p = 0.168). Interestingly, group PC had a higher value of MDA than group CC (p = 0.026). The volume fraction of myocardium with detection of 15-F2tisoprostane is higher in PC (p = 2.884x10-5), CP (p = 6.632x10-6) and PP (p = 5.45x10-8) than in CC. The value of PP in higher than those of PC and CP (p = 3.661x10-4 and 1.058x10-3, respectively), while the latter two were equal to each other (p = 0.624). ). The mean ratio of arterioles wiht lumen area between 200 and 1000?m² to the total number of vessels in each group was higher in PP than in CC and PC (p=0.0387 and p=0.0362, respectively). These results, which suggest that exposure to air pollution is associated to higher levels of lipid peroxidation in the myocardium, are compared to other results previously published about respiratory and reproductive alterations related to pollution. Interestingly, the increased levels of lipid peroxidation in the PC group gives evidence that the prenatal exposure to urban air pollution can be linked to cardiovascular effects in adult life.
Paraiso, Maria Leticia de Souza. „Avaliação do impacto à saúde causado pela queima prévia de palha de cana-de-açúcar no Estado de São Paulo“. Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5137/tde-20022014-145043/.
Der volle Inhalt der QuelleEthanol from sugarcane is consolidated as a renewable fuel which promotes further expansion of the culture of sugarcane in Brazil and especially in the State of São Paulo. As the controlled pre-harvest burning of sugarcane straw is still considered an agricultural practice necessary for the economic viability of this crop in more than 70% of municipalities in the State of São Paulo the population is forced to live with this pollution. To study the distribution of this risk factor and its relationship with the health of the population, I conducted an ecological study in the 645 municipalities of São Paulo. I used a Bayesian multivariate regression model relating the health effects and the exposure to previous straw burning of sugarcane, controlling the effects of socioeconomic factors (sanitation, education and income) and climate (maximum temperature, minimum humidity and precipitation) by the insertion of these variables in the model. The effect on health was measured by Standardized Mortality and Morbidity Ratio (SMR) of the outcomes: deaths from respiratory diseases in the age group above 65 years old and admissions for respiratory disease in children less than 5 years old and above 65 years old of each of the municipalities. I used as a measure of exposure to the pre-harvest burning data obtained at INPE: percent of sugarcane area harvest with burning (PMQ), levels of Aerosol and Spotlights of burning, tested separately. To solve the autocorrelation in the data these were considered as their spatial arrangement, by building a neighborhood matrix of the 645 municipalities in the state. I used the Markov Chain-Monte Carlo simulation method (MCMC) to \'soften\' the estimates of the SMR. The analysis showed that there is an association between previous straw burning of sugarcane and respiratory diseases, because the increase in outbreaks of burning (Spotlights) was significantly associated with increased hospital admissions for respiratory diseases in children aged under five years old. The results show that the previous straw burning of sugarcane effectively offers health risk to the population and added to the choropleth maps generated provide valuable information for epidemiological surveillance and contribute to the establishment of public policies for the control of air pollution, which should contemplate beyond the major urban centers, the small towns. The elimination of this risk factor should be part of a primordial prevention measure to be taken in the state
Tsai, Shang-Shyue, und 蔡尚學. „Effects of Air Pollution on Adverse Health Outcomes in Taiwan“. Thesis, 2003. http://ndltd.ncl.edu.tw/handle/4fj9tz.
Der volle Inhalt der Quelle高雄醫學大學
醫學研究所
91
The tiny island of Taiwan is densely populated and the distances between industrial districts and residential regions are commonly short. Therefore, comparatively speaking, it is even more important to investigate the effects of air pollution on adverse health outcomes in Taiwan. The objectives of this study were (1) to determine whether women living in the specific air-polluted vicinity are highly correlated with increasing incidences of preterm births, and (2) to investigate whether air pollution is associated with daily mortality and daily hospital admission for stroke. In a vicinity of industrial districts where emission levels of air contaminants from multiple sources including petrochemical, petroleum, steel and shipbuilding industries, we found that the prevalence of delivery of preterm birth infants was significantly higher in comparing the control regions. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, infant gender and birthplace), the adjusted odds ratio was 1.11 (95% CI=1.02-1.21) for delivery of preterm infants in this industrial area. Moreover, the prevalence of delivery of preterm birth infants was also significantly higher in mothers living within 0-3 km of thermal power plants compared to mothers living within 3-4 km. The adjusted odds ratio was 1.14 (95% CI=1.01-1.30). To examine the relationship between air pollution and daily mortality/hospital admission in Kaohsiung, the largest industrial city in Taiwan, we used a case-crossover design which is an alternative to Poisson time series regression for studying the short-term adverse health effects of air pollution. For the period of 1994-2000, no significant effects were found between five pollutants (PM10, SO2, CO, NO2, O3) and non-accidental deaths, respiratory-related deaths and cardiovascular disease deaths. For the period of 1997-2000, statistically significant positive associations were found between levels of PM10, NO2, CO, and O3, and both intracerebral haemorrhagic stroke (IHS) and ischemic stroke (IS) admissions on warm days (20C) in the single pollutant models. On cool days (<20C), only CO levels and IS admissions were significantly associated. The two-pollutant models, PM10 and NO2 remained consistently and significantly associated with admissions for both types of stroke on warm days. We observed estimated relative risks of 1.552 (1.336-1.804) and 1.589 (1.364-1.852) for IHS for each interquartile range increase in PM10 and NO2. The values for IS were 1.461 (1.323-1.613) and 1.545 (1.398-1.708) respectively. Our data provide further supports for the hypothesis that air pollution can affect the outcome of pregnancy, although a semi-ecological study cannot confirm a direct causal relationship. The factors such as differences in meteorological condition, pollutant mixtures or underlying health of the population may explain the lack of a strong association between air pollution levels and daily mortality in Kaohsiung. Further studies of this type in cities with varying climates and cultures are needed. Nevertheless, this study provides an association between exposure to air pollution and hospital admissions for stroke.
He, Mike Zhongyu. „Air pollution and adverse health effects: Assessing exposure windows and sensitivity to modeling choices“. Thesis, 2020. https://doi.org/10.7916/d8-dc4c-z009.
Der volle Inhalt der Quelle„Short-term effects of particulate matter pollutants on population health: time series studies on emergency hospital admissions“. 2012. http://library.cuhk.edu.hk/record=b5549611.
Der volle Inhalt der Quelle研究目的:以每天心血管系統、呼吸系統疾病急性入院人為研究結局,區別估計顆污染物PM₁₀ 中粗、細顆的健康危害作用,并探討PM₁₀與氣態污染物(二氧化氮,NO₂;二氧化,SO₂;臭氧,O₃)的交互作用。
研究方法:收集香港1998 1 月至2007 12 月每天心腦血管疾病、呼吸系統疾病急性入院人,日均污染物濃,日均氣溫、相對濕等資,採用時間序分析的研究方法,應用Poisson 廣義相加模型分析顆污染物中粗、細顆的同健康效應。同時應用三個平的時間序研究模型(雙變反應面模型、合效應模型和分層模型)探討顆污染物和氣態污染物之間潛在的交互作用。
研究結果:研究發現,在校正PM₂.₅的影響后,PMc 對呼吸系統疾病導致的急性入院作用顯著,但對心腦血管疾病引起的急性入院則無明顯作用。在雙污染物(PMc 和PM₂.₅)模型中,空氣中每一個IQR(四分位間距)的PM[subscript c] 和PM₂.₅濃的增加將使每天急性呼吸系統疾病入院分別增加1.05% (95% CI: 0.19%, 1.91%)和1.81% (95% CI: 0.78%,2.87%),使急性心腦血管疾病入院分別改變 -0.16% (95% CI: -1.07%,0.76%) 和1.86% (95% CI: 0.85%, 2.88%)。研究發現某種程6 的顆污染物和氣態污染物的交互作用。在NO₂ 或SO₂ 高水平(NO₂ 濃高於64.4μg/m³ 或 SO₂ 濃高於20.9μg/m³)的日子,PM₁₀ 對急性心臟疾病入院的影響高於NO₂ 或SO₂ 低、中水平的日子;而在臭氧高水平(O₃濃高於46.8μg/m³)的日子,PM₁₀ 對急性呼吸和循環系統疾病入院的作用低於O₃ 中、低水平的日子。
研究結:粗、細顆污染物對呼吸系統疾病的危害均作用顯著且相對獨,但對循環系統疾病的危害作用則主要體現於細顆污染物。同時,顆性污染物的健康危害可能被空氣中的氣態污染物水平所修飾:研究發現PM₁₀ 與NO₂ 或SO₂ 之間的協同作用,以及PM₁₀ 與O₃ 之間的拮抗作用。
BACKGROUND: The adverse effects of particulate matter (PM) air pollution have been confirmed by many epidemiological studies. Fine and coarse particles should be considered as separate classes of pollutants and measured separately. Differentiating the effects of fine (PM₂.₅, particles with an aerodynamic diameter less than 2.5 microns) and coarse particles (PM[subscript c], particles with an aerodynamic diameter between 2.5 and 10 microns) would help in the future to support a PM[subscript c] standard. Meanwhile, ambient air pollution is a complex mixture of PM and gaseous pollutants. PM might interact with gaseous pollutants to affect the population health.
STUDY OBJECTIVES: To differentiate the effects of fine and coarse fractions of PM₁₀ and to explore the possible interaction between PM₁₀ and gaseous pollutants (nitrogen dioxide, NO₂; sulfur dioxide, SO₂; ozone, O₃) on emergency hospital admissions for cardio-respiratory diseases in Hong Kong.
METHODS: This is a time series study. Daily counts of emergency hospital admissions for cardio-respiratory diseases, daily mean air pollution concentrations and weather conditions were collected from January 1998 to December 2007 in Hong Kong. We used generalized additive Poisson model with log link allowing overdispersion and autocorrelation to examine the differential effects of PM₂.₅ and PM[subscript c]. Three parallel time series approaches (bivariate response surface model, joint effect model and parametric stratified model) were used to explore the possible interactions between PM₁₀ and gaseous pollutants.
MAIN RESULTS: The associations between PM[subscript c] and emergency hospital admissions were statistically significant for respiratory diseases but not for circulatory diseases. In two-pollutant (PM₂.₅and PM[subscript c]) model, an interquartile range increase in the 4-day moving average (lag₀₃) concentrations of PM[subscript c] and PM₂.₅ corresponded to 1.05% (95% CI: 0.19%, 1.91%) and 1.81% (95% CI: 0.76%, 2.87%) increase of respiratory admissions, respectively. The effect estimates of PM₂.₅and PM[subscript c] remained robust when adjusting for gaseous pollutants. Meanwhile, an interquartile range increase in lag₀₁ concentrations of PM[subscript c] and PM₂.₅was associated with -0.16% (95% CI: -1.07%, 0.76%) and 1.86% (95% CI: 0.85%, 2.88%) change of circulatory admissions, respectively. Some interactions between PM₁₀ and gaseous pollutants were found. The effects of PM₁₀ on circulatory hospitalizations were greatest during the days when NO₂ or SO₂ concentrations were high (the 3rd tertile, NO₂>64.4 or SO₂>20.9μg/m³). The effects of PM₁₀ on both respiratory and circulatory admissions were greatest during the days when O₃ concentrations were in low to medium levels (<=46.8μg/m³).
CONCLUSION: We found PM[subscript c] to be associated with emergency hospital admissions for respiratory diseases independent of the effect of PM₂.₅, but not for circulatory diseases in Hong Kong. The effects of PM₁₀ on cardio-respiratory hospital admissions were modified by gaseous pollutants. There were synergetic interactions between PM₁₀ and NO₂ or SO₂ on cardiac hospitalizations and antagonistic interactions between PM₁₀ and ozone on cardio-respiratory hospitalizations. These findings provide supportive evidence for a future PM[subscript c] regulation and contribute to the development of a multipollutant air quality management.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Qiu, Hong = 顆粒污染物對人群健康的短期效應 : 時間序列研究 / 邱宏.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2012.
Includes bibliographical references (leaves 122-137).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.
Qiu, Hong = Ke li wu ran wu dui ren qun jian kang de duan qi xiao ying : shi jian xu lie yan jiu / Qiu Hong.
Abstract (English) --- p.v
Abstract (Chinese) --- p.viii
List of Contents --- p.x
List of Tables --- p.xiv
List of Figures --- p.xvi
List of Abbreviation --- p.xviii
Acknowledgements --- p.xix
Chapter Chapter 1 --- Introduction --- p.1
Chapter Chapter 2 --- Literature Review --- p.5
Chapter 2.1. --- Review on the differential health effects of fine and coarse particles --- p.5
Chapter 2.1.1 --- A brief description of particulate matter air pollution --- p.5
Chapter 2.1.2 --- The objective of this part of literature review --- p.7
Chapter 2.1.3 --- Methods --- p.8
Chapter 2.1.3.1 --- Inclusion and exclusion criteria of studies/papers --- p.8
Chapter 2.1.3.2 --- Search terms and keywords --- p.9
Chapter 2.1.3.3 --- Information abstracted --- p.9
Chapter 2.1.4 --- Results --- p.10
Chapter 2.1.4.1 --- Short-term effects of PM₂.₅and PM[subscript c] on mortality --- p.10
Chapter 2.1.4.2 --- Short-term effects of PM₂.₅and PM[subscript c] on morbidity --- p.14
Chapter 2.1.4.3 --- Biological mechanisms underlying the differential effects of PM₂.₅and PM[subscript c] --- p.18
Chapter 2.1.5 --- Conclusion remarks --- p.19
Chapter 2.1.5.1 --- Health effects of PM₂.₅and PM[subscript c] on mortality --- p.19
Chapter 2.1.5.2 --- Health effects of PM₂.₅and PM[subscript c] on morbidity --- p.20
Chapter 2.2. --- Review on the joint effects/interactions of particulate matter and gaseous pollutants --- p.21
Chapter 2.2.1 --- Concept of Interaction --- p.21
Chapter 2.2.2 --- The objective of this part of literature review --- p.21
Chapter 2.2.3 --- Methods --- p.22
Chapter 2.2.3.1 --- Search terms and key words --- p.22
Chapter 2.2.3.2 --- Information abstract --- p.22
Chapter 2.2.4 --- Results --- p.23
Chapter 2.2.4.1 --- Studies on the interaction between particulate matter and gaseous pollutants --- p.23
Chapter 2.2.4.1.1 --- Studies on the interaction between PM₁₀ and NO₂ --- p.23
Chapter 2.2.4.1.2 --- Studies on the interaction between PM₁₀ and O₃ --- p.24
Chapter 2.2.4.1.3 --- Studies on the interaction between PM and SO₂ --- p.26
Chapter 2.2.4.1.4 --- Modifiers identified through multicity study --- p.30
Chapter 2.2.4.2 --- Methodology used to detect interaction in time series studies --- p.33
Chapter 2.2.4.2.1 --- Nonparametric bivariable response surface model --- p.33
Chapter 2.2.4.2.2 --- Non-stratification interaction model --- p.34
Chapter 2.2.4.2.3 --- Parametric stratified model --- p.34
Chapter 2.2.4.2.4 --- Time series classification and regression tree (CART) model --- p.35
Chapter 2.2.4.3 --- Biological mechanisms of interaction between pollutants --- p.36
Chapter 2.2.5 --- Conclusion remarks --- p.38
Chapter Chapter 3 --- Differential health effects of fine and coarse particles --- p.39
Chapter 3.1 --- Objectives --- p.39
Chapter 3.2 --- Materials and Methods --- p.39
Chapter 3.2.1 --- Data on particulate pollutants and meteorology variables --- p.39
Chapter 3.2.2 --- Data on emergency hospital admissions for cardio-respiratory diseases --- p.40
Chapter 3.2.3 --- Statistical models --- p.42
Chapter 3.2.3.1 --- Core model set up --- p.42
Chapter 3.2.3.2 --- Single-pollutant and two-pollutant models --- p.44
Chapter 3.2.3.3 --- Concentration-response relationship --- p.45
Chapter 3.2.3.4 --- Sensitivity analysis --- p.46
Chapter 3.3 --- Results --- p.47
Chapter 3.3.1 --- Location of Tsuen Wan station, Tsuen Wan region --- p.47
Chapter 3.3.2 --- Air pollution concentrations and meteorological factors --- p.47
Chapter 3.3.3 --- Emergency hospital admissions for cardio-respiratory diseases --- p.50
Chapter 3.3.4 --- Regression results and Sensitivity analysis --- p.51
Chapter 3.3.4.1 --- Effects of coarse particulate matter on emergency hospital admissions for respiratory diseases --- p.51
Chapter 3.3.4.2 --- Differential effects of fine and coarse particles on emergency hospital admissions for cardiovascular diseases --- p.56
Chapter 3.4 --- Discussion --- p.61
Chapter 3.4.1 --- Main findings of this study --- p.61
Chapter 3.4.2 --- Compared with findings from the literature --- p.62
Chapter 3.4.3 --- Exposure windows selection and possible misclassification --- p.64
Chapter 3.4.4 --- Sensitivity analyses of main findings --- p.65
Chapter 3.4.5 --- Biological mechanisms of the differential effects of fine and coarse particles --- p.67
Chapter 3.4.6 --- Limitations of this study --- p.68
Chapter 3.5 --- Conclusion and recommendations --- p.69
Chapter Chapter 4 --- Joint effects/Interactions of PM₁₀ and gaseous pollutants --- p.70
Chapter 4.1 --- Objectives --- p.70
Chapter 4.2 --- Materials and Methods --- p.70
Chapter 4.2.1 --- Data on air pollution and meteorology variables --- p.70
Chapter 4.2.2 --- Data on emergency hospital admissions for cardio-respiratory diseases --- p.71
Chapter 4.2.3 --- Statistical models --- p.72
Chapter 4.2.3.1 --- Core model set up --- p.72
Chapter 4.2.3.2 --- Three parallel time series models --- p.73
Chapter 4.3 --- Results --- p.76
Chapter 4.3.1 --- Air pollution concentrations and meteorological factors --- p.76
Chapter 4.3.2 --- Emergency hospital admissions for cardio-respiratory diseases --- p.79
Chapter 4.3.3 --- Results from single-pollutant model --- p.81
Chapter 4.3.3.1 --- Pollution effects on emergency hospital admissions for respiratory diseases --- p.81
Chapter 4.3.3.2 --- Pollution effects on emergency hospital admissions for circulatory diseases --- p.83
Chapter 4.3.4 --- Joint effects/Interactions between PM₁₀ and NO₂ on cardio-respiratory hospitalizations --- p.85
Chapter 4.3.5 --- Joint effects/Interactions between PM₁₀ and O₃ on cardio-respiratory hospitalizations --- p.91
Chapter 4.3.6 --- Joint effects/Interactions between PM₁₀ and SO₂ on cardio-respiratory hospitalizations --- p.96
Chapter 4.4 --- Discussion --- p.102
Chapter 4.4.1 --- Main findings --- p.102
Chapter 4.4.1.1 --- Effect estimates compared with previous Hong Kong studies --- p.102
Chapter 4.4.1.2 --- Interactions between particulate matter and gaseous pollutants --- p.103
Chapter 4.4.1.2.1 --- Interactions between PM₁₀ and NO₂ on cardiac hospitalizations --- p.103
Chapter 4.4.1.2.2 --- Interactions between PM₁₀ and O₃ on cardio-respiratory hospitalizations --- p.109
Chapter 4.4.1.2.3 --- Interactions between PM₁₀ and SO₂ on cardiac hospitalizations --- p.113
Chapter 4.4.2 --- Strengths and limitations of this study --- p.116
Chapter 4.5 --- Conclusion and recommendations --- p.119
Chapter Chapter 5 --- Concluding remarks --- p.120
References List --- p.122
Chapter Appendix --- Relevant Publications and Submitted/Drafted Papers --- p.138
„In vitro cytotoxicity of metal ions and roadside dust collected in Hong Kong“. 2002. http://library.cuhk.edu.hk/record=b5895982.
Der volle Inhalt der QuelleThesis (M.Phil.)--Chinese University of Hong Kong, 2002.
Includes bibliographical references (leaves 135-144).
Abstracts in English and Chinese.
Acknowledgements --- p.i
Abstract --- p.ii
Abbreviations --- p.vi
List of figures --- p.viii
List of tables --- p.xi
Contents --- p.xiii
Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- General introduction --- p.1
Chapter 1.2 --- Roadside air pollution worldwide and in Hong Kong --- p.2
Chapter 1.2.1 --- Air quality in Hong Kong --- p.3
Chapter 1.3 --- Characteristics of particulate matter --- p.9
Chapter 1.4 --- Composition and sources of particulate matter --- p.11
Chapter 1.5 --- Toxic effects of particulate matter --- p.12
Chapter 1.5.1 --- Lung injury --- p.12
Chapter 1.5.2 --- Cardiovascular injury --- p.15
Chapter 1.5.3 --- Mutagenesis and carcinogenesis --- p.16
Chapter 1.6 --- Aims of my study --- p.16
Chapter 2 --- Toxic Effects of Heavy Metals Ions on Selected Cultured Cell-lines --- p.18
Chapter 2.1 --- Introduction --- p.18
Chapter 2.1.1 --- Metals --- p.18
Chapter 2.1.1.1 --- Cadmium --- p.22
Chapter 2.1.1.2 --- Chromium --- p.23
Chapter 2.1.1.3 --- Lead --- p.25
Chapter 2.1.1.4 --- Zinc --- p.26
Chapter 2.1.2 --- Metallothioneins --- p.28
Chapter 2.1.3 --- p53 --- p.31
Chapter 2.1.4 --- Tumor Necrosis Factor-alpha (TNF-α) --- p.32
Chapter 2.1.5 --- Aims of this chapter --- p.32
Chapter 2.2 --- Materials and methods --- p.35
Chapter 2.2.1 --- Reagents --- p.35
Chapter 2.2.2 --- Cultured Cell lines --- p.35
Chapter 2.2.2.1 --- PU5-18 --- p.36
Chapter 2.2.2.2 --- LL24 --- p.36
Chapter 2.2.2.3 --- HBE4-E6/E7 --- p.37
Chapter 2.2.3 --- Cytotoxicity assays --- p.37
Chapter 2.2.4 --- ELISA assays --- p.40
Chapter 2.2.4.1 --- ELISA assay ofp53 levels --- p.41
Chapter 2.2.4.2 --- ELISA assay of TNF-α levels --- p.43
Chapter 2.2.5 --- MT gene expression studies by Luciferase assay --- p.44
Chapter 2.2.5.1 --- PCR amplification --- p.44
Chapter 2.2.5.2 --- 5´ة End modification of PCR amplified DNA --- p.44
Chapter 2.2.5.3 --- Ligation of DNA fragment to linearized vector --- p.46
Chapter 2.2.5.4 --- E. coli. transformation by heat shock --- p.46
Chapter 2.2.5.5 --- PCR sequencing --- p.47
Chapter 2.2.5.6 --- Transfection of plasmid into HBE4-E6/E7 cells --- p.49
Chapter 2.2.5.7 --- Data analysis --- p.50
Chapter 2.3 --- Results and discussion --- p.51
Chapter 2.3.1 --- Cytotoxicity assays --- p.51
Chapter 2.3.2 --- Combination effects of metals on cytotoxicity --- p.61
Chapter 2.3.3 --- p53 --- p.65
Chapter 2.3.4 --- TNF-α --- p.68
Chapter 2.3.5 --- MT gene expression studies by Luciferase assay --- p.69
Chapter 2.4 --- Conclusion --- p.74
Chapter 3 --- Effects of Polycyclic Aromatic Hydrocarbons (PAHs) on Cultured Cell-lines --- p.75
Chapter 3.1 --- Introduction --- p.75
Chapter 3.2 --- Materials and methods --- p.79
Chapter 3.2.1 --- Reagents --- p.79
Chapter 3.2.2 --- Cell culture --- p.79
Chapter 3.2.3 --- AlamarBlue assay --- p.80
Chapter 3.2.4 --- EROD assay --- p.80
Chapter 3.3 --- Results and discussion --- p.84
Chapter 3.4 --- Conclusion --- p.88
Chapter 4 --- Chemical and Biological Assays on Roadside Dust --- p.89
Chapter 4.1 --- Introduction --- p.89
Chapter 4.1.1 --- Composition of particulate matter in Hong Kong --- p.89
Chapter 4.1.2 --- Metal contents of particulate matter in Hong Kong --- p.91
Chapter 4.1.3 --- Possible adverse health impacts of particulate matter --- p.94
Chapter 4.1.3.1 --- In vitro studies using different cell models --- p.94
Chapter 4.1.3.2 --- In vivo studies using rodents --- p.97
Chapter 4.1.3.3 --- Epidemiological studies --- p.98
Chapter 4.1.4 --- Aims of this chapter --- p.100
Chapter 4.2 --- Materials and methods --- p.101
Chapter 4.2.1 --- Sampling of roadside dust --- p.101
Chapter 4.2.2 --- Chemical analysis of roadside dust --- p.104
Chapter 4.2.2.1 --- Reagents --- p.104
Chapter 4.2.2.2 --- Total metal contents --- p.105
Chapter 4.2.2.3 --- Extractable metal contents --- p.105
Chapter 4.2.3 --- Biological assays --- p.105
Chapter 4.2.3.1 --- Cell models --- p.106
Chapter 4.2.3.2 --- Pretreatment of roadside dust --- p.106
Chapter 4.2.3.3 --- AlamarBlue assay --- p.106
Chapter 4.2.3.4 --- ELISA assays --- p.108
Chapter 4.2.3.5 --- Luciferase assay --- p.108
Chapter 4.3 --- Results and discussion --- p.110
Chapter 4.3.1 --- Total metal contents --- p.110
Chapter 4.3.2 --- Extractable metal contents --- p.113
Chapter 4.3.3 --- AlamarBlue assay --- p.116
Chapter 4.3.4 --- p53 --- p.122
Chapter 4.3.5 --- TNF-α --- p.122
Chapter 4.3.6 --- Luciferase assay --- p.126
Chapter 4.4 --- Conclusion --- p.129
Chapter 5 --- General discussion and conclusion --- p.130
Chapter 6 --- References --- p.135
„Long-term exposure to air pollution and school children's respiratory health and lung function growth: a 1-year prospective cohort study in Guangzhou, China“. Thesis, 2009. http://library.cuhk.edu.hk/record=b6074729.
Der volle Inhalt der QuelleThesis (Ph.D.)--Chinese University of Hong Kong, 2009.
Includes bibliographical references (leaves 142-154).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in English and Chinese.
„Ambient air pollution and school children's respiratory health, lung functions and cardiopulmonary fitness in Hong Kong: a cross-sectional study“. Thesis, 2005. http://library.cuhk.edu.hk/record=b6074123.
Der volle Inhalt der QuelleIn the past year preceding the study (May 2003 to April 2004), the annual means for PM10, NO2, SO2 and O3 were respectively 55.1 mug/m3, 51.4 mug/m3, 15.4 mug/m3, and 42.5 mug/m3 in the least-polluted district (LPD); 56.3 mug/m3, 64.7 mug/m3, 15.2 mug/m3, and 35.2 mug/m3 in the moderately-polluted district (MPD); and 63.8 mug/m3, 64.1 mug/m3, 22.2 mug/m3, and 31.7 mug/m3 in the highly-polluted district (HPD). The 99th percentiles were 178 mug/m3, 158 mug/m 3, 104 mug/m3, and 140 mug/m3 in the LPD; 169 mug/m3, 181 mug/m3, 106 mug/m 3, and 113 mug/m3 in the MPD; and 226 mug/m 3, 177 mug/m3, 140 mug/m3, and 137 mug/m 3 in the HPD. The average daily 1-h maximum O3 (peak O 3) was 83.7 mug/m3 in the LPD, 73.6 mug/m 3 in the MPD, and 64.8 mug/m3 in the HPD.
Lung function indices included FVC, FEV1, FEV 1/FVC, FEF25-75%, FEF25%, and FEF75%. Children in the HPD had lower FEV 1/FVC, FEF25-75%, and FEF25% than those in both the LPD and MPD, after controlling for their corresponding confounders. In comparison between the LPD and HPD, the adjusted mean differences for FEV1/FVC, FEF25-75%, and FEF25% were respectively 1.39%, 85 ml, and 113 ml in boys, and 1.60%, 86 ml, and 225 ml in girls. In addition, the decreased FEF75% of HPD was found in boys (62 ml) but not in girls. When comparing the MPD with LPD, the increased FEF25% was observed in girls in the LPD (158 ml), whereas boys in the LPD had lower FEF75% than those in the MPD (81 ml). There were no significant differences in children's FVC and FEV1 between districts.
The multistage fitness test (MFT) with the Matsuzaka's function was employed to predict cardiopulmonary fitness (VO2max) of children. After adjustment for the factors, girls in the LPD had significantly higher VO 2max than those in the MPD and HPD by 0.19 and 0.75 ml·kg -1 ·min-1 respectively. The VO 2max among boys in the LPD was 0.48 ml·kg-1 ·min -1 higher than those in the HPD. When we compared the VO 2max between students in MPD and HPD, higher VO2max in both boys and girls in the MPD were observed---by 0.49 and 0.56 ml·kg -1 ·min-1 respectively. In LPD, significantly higher VO2max values were observed in both boys and girls who were physically active (children who took part in sports and/or vigorous free play at least three times a week for at least 30 minutes each time) compared with those who were not (0.71 and 0.65 ml·kg-1 ·min -1 respectively), but those differences in VO2max among students in MPD and HPD were small and insignificant.
There were totally 2,641 (82.9%) children who participated in the study, and 2,203 participants were involved in analyses. After adjustment for confounding factors, girls living in the HPD had significantly increased odds ratios (ORs) for wheezing without cold (4.75), cough at night (1.71), phlegm without cold (3.61), compared with those in the LPD. Boys in the HPD had increased OR only for phlegm without cold (1.88). When comparing the MPD with LPD, the adjusted OR for cough at night achieved significance in girls (1.74) and marginal significance in boys (1.40). Sneeze with itchy-watery eyes and current/ever allergic rhinitis had negative associations with district. In comparison with LPD, the decreased OR for sneeze with itchy-watery eye in girls in HPD (0.65) reached statistical significance. Both boys and girls in MPD had significantly decreased ORs for current allergic rhinitis (0.72 and 0.50 respectively) and for ever allergic rhinitis (0.74 and 0.55 respectively). There were no significant differences in the prevalence rates of asthma and bronchitis between districts.
To explore associations between air pollution and respiratory and cardiovascular health of school children, a cross-sectional study was conducted among 3,186 primary school children in P3 and P4 from three districts with different air pollution levels in Hong Kong during March to June in 2004.
Gao Yang.
"August 2005."
Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6339.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2005.
Includes bibliographical references (p. 137-154).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in English and Chinese.
School code: 1307.