792 resultados para smoke


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There is increasing evidence of a causal link between airborne particles and ill health and this study examined the exposure to both airborne particles and the gas phase contaminants of environmental tobacco smoke (ETS) in a bar. The work reported here utilized concurrent and continuous monitoring using real-time optical scattering personal samplers to record particulate (PM10) concentrations at two internal locations. Very high episodes were observed in seating areas compared with the bar area. A photo-acoustic multi-gas analyser was used to record the gas phases (CO and CO2) at eight different locations throughout the bar and showed little spatial variation. This gave a clear indication of the problems associated with achieving acceptable Indoor Air Quality in a public space and identified a fundamental problem with the simplistic design approach taken to ventilate the space. Both gaseous and particulate concentrations within the bar were below maximum recommended levels although the time-series analysis illustrated the highly episodic nature of this exposure.

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Chionanthus pygmaeus Small (pygmy fringetree) (Oleaceae) is an endemic and rare Florida species, which has an attractive, small habit giving it great potential for use in managed landscapes. Members of the genus Chionanthus are difficult to propagate via cuttings and possess complex seed dormancies that are not well understood. Conservation of pygmy fringetree and its potential for commercial propagation for use in managed landscapes is contingent on a better understanding of its complex seed dormancy and enhancement of its propagation. I conducted two experiments to assess sexual and asexual propagation methods for pygmy fringetree. The first experiment was conducted to determine what factors are involved in overcoming seed dormancy. Various scarification treatments, which mimicked conditions seeds are exposed to in the wild, were investigated to determine their effects on germination of 20-year-old seeds originally collected from the species’ native range. Treatments included endocarp removal, sulfuric acid, boiling-water, and smoke-water treatments. Prior to treatment initiation, seed viability was estimated to be 12%. Treated seeds went through two cold- and two warm-stratification periods of 4°C and 25°C, respectively, in a dark growth chamber. After 180 days, none of the treatments induced early germination. Seeds were then tested for viability, which was 11%. Seed dormancy of the species is apparently complex, allowing some of the seeds to retain some degree of viability, but without dormancy requirements satisfied. The second experiment was conducted to assess if pygmy fringetree could be successfully propagated via hardwood or root cuttings if the appropriate combination of environmental conditions and hormones were applied. Hardwood and root cuttings were treated with either 1000 ppm IBA talc, 8000 ppm IBA talc, or inert talc. All cuttings were placed on a mist bench in a greenhouse for 9 weeks. Hardwood cuttings were supplemented with bottom heat at 24 °C. No treatments were successful in inducing adventitious root formation. I conclude that pygmy fringetree seeds possess complex dormancy that was not able to be overcome by the treatments utilized. However, this result is confounded by the age of the seeds used in the experiment. I also conclude that vegetative propagation of pygmy fringetree is highly dependent on the time of year cuttings are harvested. Further research of both seed and asexual propagation methods need to be explored before pygmy fringetree can be propagated on a commercial scale.

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Knowledge on human behaviour in emergency is crucial to increase the safety of buildings and transportation systems. Decision making during evacuations implies different choices, of which one of the most important concerns the escape route. The choice of a route may involve local decisions between alternative exits from an enclosed environment. This work investigates the influence of environmental (presence of smoke, emergency lighting and distance of exit) and social factors (interaction with evacuees close to the exits and with those near the decision-maker) on local exit choice. This goal is pursued using an online stated preference survey carried out making use of non-immersive virtual reality. A sample of 1,503 participants is obtained and a Mixed Logit Model is calibrated using these data. The model shows that presence of smoke, emergency lighting, distance of exit, number of evacuees near the exits and the decision-maker, and flow of evacuees through the exits significantly affect local exit choice. Moreover, the model points out that decision making is affected by a high degree of behavioural uncertainty. Our findings support the improvement of evacuation models and the accuracy of their results, which can assist in designing and managing building and transportation systems. The main contribution of this work is to enrich the understanding of how local exit choices are made and how behavioural uncertainty affects these choices.

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OBJETIVO: El presente estudio tiene como objetivo determinar las conductas de riesgo de los adolescentes escolarizados que frecuentan los bares y discotecas de la “Calle Larga” de la ciudad de Cuenca (Calle del Centro Histórico, donde se sitúa la mayor cantidad de centros de diversión nocturna). MATERIALES Y MÉTODOS: Se trata de un estudio descriptivo, de tipo cuantitativo, transversal. Incluye un universo de 307 adolescentes, del Cantón Cuenca en el año 2014. (1) Los datos fueron recolectados mediante un formulario validado, que fue aplicado previo asentimiento y/o consentimiento informado de los adolescentes entre 10 y 19 años que acuden a “La Calle Larga” los días viernes y sábados durante el mes de Mayo del año 2014. RESULTADOS: En el estudio encontramos que el 67,75% de adolescentes ingiere alcohol, el 28,66% fuma cigarrillo y el 8.79% fuma marihuana, siendo ésta la sustancia ilícita de elección. CONCLUSIONES: La prevalencia de consumo para alcohol, cigarrillo y otras drogas en los adolescentes que asisten a sitios de diversión nocturna en la “Calle Larga”, Cuenca mayo 2014, fue mayor en la adolescencia tardía y constituyen conductas de riesgo la compañía de los amigos. PALABRAS CLAVE: ADOLESCENCIA, ALCOHOL, CIGARRILLO, OTRAS DROGAS.

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Cold smoking method is one of the commonest ways for fish smoking. It is done by the smoke that is the result of burning hard and soft woods is smoking rooms. Smoke includes a number of chemical constructs and its main part is poly aromatic hydrocarbons. More than one hundred kinds of these constructs are recognized in smoke that is produced from saturated hydrocarbons resulted from the solution of the woods Ligno cellulose in high temperature and lack of oxygen conditions. The high poisoning potentials and carcinogenic features sixteen constructs among them are proved and observed on humans. In this research, the PAH compounds were identified and observed in a three month period after smoking and during storing among three types of smoked fishes Silver carp and Caspian sea Sefid and herring. They are the most produced and consumed smoked fish in Iran. To find the relationship between the concentrations of PAH constructs and the amount of lipid in fish, first, the amount of lipid were determined separately in the skin and flesh of 30 samples of each type. The method used was Bligh and Dyer (1959). PAH compounds derivation were made for all skin and flesh samples smoked fish using organic solvents with Soxeleh and the derived samples were injected to gas chromatography (GC) by Hamilton injectors for determining their components quality and their quantity. The height of the used column was 25 meters and its diameter was 0.32 mm with the silica filler, nitrogen gas as carrier and flame ionization detector (FID) that are special for these constructs. For data analysis, Statistical tests were used by computer soft ware identified that the difference in the amount of lipid within the flesh and skin of each species and also among each other is significant. The largest amount was in Herrings flesh and skin, 18.74% in skin and 14.47% in flesh. The least amount in the skin 4.19% and the flesh 3.10% of Sefid. The amount in Silver carp was 13.28%in skin and 8.16% in flesh. The examination of the PAH compounds in smoked fish showed that is carcinogenic compounds; exist in these in these fish with different quantities in each. It seems that its amount is directly related to the amount of their lipid. The amount is different in flesh and skin. One of the most important reasons is the direct content of smoke and the concentration of lipid in tissues of all three types. The maintenance of the smoked fish for three months showed that most of PAH compounds were solved and their density decreased. The changes in density within time in different in each type and in flesh and skin. The amount of their receiving in human through the consumption of the smoked fish depends on the resulted density, the way and the amount of consumption and now we can determine and execute standards for the maximum dosage per day and per month regarding effective factors.

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Background: Recent publications show that smoking and alcohol use among adolescents with unplanned pregnancy is increasing and the causes need to be further studied. Objective: To determine the association between living in a non-intact family household and the presence of smokers and consumers of alcoholic beverages in the adolescents’ environment with smoking and consuming alcoholic beverages in adolescents with unplanned pregnancies. Methods: A cross-sectional study was carried out among 785 pregnant adolescents, aged 13-19 years. Data was collected by trained interviewers using a self-administered questionnaire. The association was determined using multivariate logistic regression analysis. Results: In adolescents with unplanned pregnancies, the prevalence of active smoking was 21.2% and of alcohol consumption, 41.5%. The percentage of smoking at home was 57.4% and alcohol consumption, 77.5%. Approximately, 80.3% of adolescents with unplanned pregnancies had friends who smoked and 90.6% consumed alcoholic beverages. Multivariate logistic regression analysis shows that having friends who smoke or who consume alcoholic beverages is the most important risk factor for substance use in adolescents with unplanned pregnancies. Smoking and alcohol consumption at home are not associated with smoking in adolescents with unplanned pregnancies. Conclusion: Socializing with friends who smoke and/or consume alcoholic beverages constitutes the most important risk factor for substance use among adolescents with unplanned pregnancies.

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 Introdução: Durante a gravidez, devido ao aumento da exigência metabólica placentária há um aumento na produção das espécies reativas de oxigénio (ROS) que podem causar, por exemplo, oxidação de ácidos graxos poli-insaturados na placenta, além disso, nesta fase ocorre um aumento na expressão da aromatase e do receptor relacionado ao estrógeno gama (ERRgama) na placenta humana. Objetivo: O objetivo do estudo foi avaliar os parâmetros de estresse oxidativo e imunomarcação da aromatase e do ERRgama na placenta humana. Métodologia: A capacidade antioxidante total (ACAP), atividade da glutamato cisteína ligase (GCL), concentração glutationa (GSH), peroxidação lipídica e imunomarcação da aromatase e do ERRgama foram analisados em tecido placentário de 58 parturientes. Estas análises foram relacionadas com os dados socio-demográficos das participantes. Resultados: Os recém-nascidos de mães fumantes nasceram com menor peso (p=0,001). A concentração de GSH diminuiu a produção da peroxidação lipídica (p<0,05), por outro lado, a atividade de GCL teve efeito oposto (p<0,001). Encontramos uma diminuição na capacidade antioxidante total e aumento da peroxidação lipídica (p<0,05) na placenta. A placenta de mães fumantes tinham menos marcação da aromatase (p=0,037) já, as mães mais velhas tiveram menos marcação do ERRgama (p=0,009) na placenta. A GSH teve efeito positivo na imunomarcação de ERRgama (p=0,001). Conclusões: A expressão da aromatase e do ERRgamma na placenta são alterados tanto por fatores exógenos, tais como o fumo do cigarro, como por fatores endógenos, tais como a concentração de GSH e a idade da mãe. Os marcadores de estresse oxidativo na placenta são mais elevados em mães mais velhas e em placenta com menor capacidade antioxidante total. 

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Study Objective: To examine the extent to which justice of decision-making procedures and interpersonal relations is associated with smoking. Setting: Ten municipalities and 21 hospitals in Finland. Design and Participants: Cross-sectional data derived from the Finnish Public Sector Study were analysed with logistic regression analysis models with generalized estimating equations. Analyses of smoking status were based on 34 021 employees. Separate models for heavy smoking (>20 cigarettes per day) were calculated for 6295 current smokers. Main results: After adjustment for age, education, socio-economic position, marital status, job contract, and negative affectivity, smokers who reported low procedural justice were about 1.4 times more likely to smoke >20 cigarettes per day compared with their counterparts with high justice. In a similar way, after adjustments, low justice in interpersonal treatment was significantly associated with an elevated prevalence of heavy smoking (odds ratio (OR) = 1.35, 95% CI = 1.03 to 1.77 for men and OR = 1.41, 95% CI = 1.09 to 1.83 for women). Further adjustment for job strain and effort-reward imbalance had little effect on these results. There were no associations between justice components and smoking status or ex-smoking. Conclusions: The extent to which employees are treated with justice in the workplace seems to be associated with smoking intensity independently of established stressors at work.

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The aim of this thesis is to test the ability of some correlative models such as Alpert correlations on 1972 and re-examined on 2011, the investigation of Heskestad and Delichatsios in 1978, the correlations produced by Cooper in 1982, to define both dynamic and thermal characteristics of a fire induced ceiling-jet flow. The flow occurs when the fire plume impinges the ceiling and develops in the radial direction of the fire axis. Both temperature and velocity predictions are decisive for sprinklers positioning, fire alarms positions, detectors (heat, smoke) positions and activation times and back-layering predictions. These correlative models will be compared with a 3D numerical simulation software CFAST. For the results comparison of temperature and velocity near the ceiling. These results are also compared with a Computational Fluid Dynamics (CFD) analysis, using ANSYS FLUENT.

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El presente estudio exploratorio evalúa la exposición al monóxido de carbono (CO), expresado en porcentaje de carboxihemoglobina (%COHb), entre los trabajadores de los centros de control vehicular (CRV) DANTON-Cuenca. Todos los trabajadores (n=55) de los CRVs de Capulispamba y Mayancela participaron en este estudio. El %COHb se determinó a partir de muestras de sangre tomadas al inicio y final de un día laboral de febrero, abril y julio de 2013. Los resultados muestran que el %COHb se incrementó del inicio al final de la jornada laboral en ambos CRVs tanto en el grupo de trabajadores que fuman y no fumadores (P<0.001). Entre los no fumadores (N=42), el %COHb al final de la jornada sobrepasó el valor límite biológico (VLB) para COHb (3.5%) únicamente en el CRV de Mayancela (4.12%, P<0.05). Entre los fumadores (N=13), los promedios de %COHb al final de la jornada sobrepasaron los VLB en ambos CRVs. Se concluye, que los trabajadores de los CRVs de Mayancela y aquellos que fuman presentan %COHb mayores al VLB.

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This study compared the prevalence of vocal problems in two Portuguese groups: 73 teachers that use their voice as professional tool (teachers’ group) and 73 non-voice professionals (control group). It also identified the risk factors that contributed to teachers’ group voice problems. A questionnaire was applied to both goups in order to obtain information about vocal health, hygiene and behavior, professional activity and general physical health. Statistical results revealed that the teachers’ group presented a higher prevalence of vocal problems than the control group: 52% reported hoarseness, 46.6% vocal fatigue and 45.2% vocal discomfort compared with 31.5%, 20.5 % e 28.7%, respectively. Environmental factors (eg., smoke and cold temperatures), vocal abuse and upper respiratory pathologies (e.g., colds, laryngitis and pharyngitis) seemed to increase teachers’ voice disorders (p-value < .05). In conclusion, the absence of vocal pedagogy in the curricular plan of teachers’ higher education associated to poor working environmental conditions and professional voice demands explained the higher prevalence of vocal problems in teachers’ group.

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During storage of smoke-dried fish, various biochemical reactions can occur; they will result in product acceptability or rejection. To determine these changes, pH and humidity were measured and molds were counted on smoke-dried fish stored for 6 months. A sensory analysis was also conducted to assess the quality of the products. Infestations and losses linked to it have been estimated by counting the insects and weighing of fish batches over time. The variability in the quality of smoke-dried fish depending on the time of purchase and storage was also integrated with our study. Biochemical reactions are mainly oxidation phenomena which result in a decrease of pH and release of spoilage odors such as rancid odor (> 1.5/ 3) or sulfur, acid and moldy odors. The growth of mold (1- 36 CFU / g) due to the reabsorption of water by fish contributes to this olfactory and visual spoilage. Beyond 90 days of storage, smoke-dried fish bought in the dry season begins to be rejected (> 2/3), while the fish bought in the wet season is at the limit of acceptability (2/3) even at the beginning of storage. During the first 90 days of storage, the insect infestation generates between 10 and 60 % of losses. A salt content of 8 % appears to be effective against the infestation but contributes to the deterioration of the product when stored in rooms with higher than 65 % relative humidity.

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Light absorption by aerosols has a great impact on climate change. A Photoacoustic spectrometer (PA) coupled with aerosol-based classification techniques represents an in situ method that can quantify the light absorption by aerosols in a real time, yet significant differences have been reported using this method versus filter based methods or the so-called difference method based upon light extinction and light scattering measurements. This dissertation focuses on developing calibration techniques for instruments used in measuring the light absorption cross section, including both particle diameter measurements by the differential mobility analyzer (DMA) and light absorption measurements by PA. Appropriate reference materials were explored for the calibration/validation of both measurements. The light absorption of carbonaceous aerosols was also investigated to provide fundamental understanding to the absorption mechanism. The first topic of interest in this dissertation is the development of calibration nanoparticles. In this study, bionanoparticles were confirmed to be a promising reference material for particle diameter as well as ion-mobility. Experimentally, bionanoparticles demonstrated outstanding homogeneity in mobility compared to currently used calibration particles. A numerical method was developed to calculate the true distribution and to explain the broadening of measured distribution. The high stability of bionanoparticles was also confirmed. For PA measurement, three aerosol with spherical or near spherical shapes were investigated as possible candidates for a reference standard: C60, copper and silver. Comparisons were made between experimental photoacoustic absorption data with Mie theory calculations. This resulted in the identification of C60 particles with a mobility diameter of 150 nm to 400 nm as an absorbing standard at wavelengths of 405 nm and 660 nm. Copper particles with a mobility diameter of 80 nm to 300 nm are also shown to be a promising reference candidate at wavelength of 405 nm. The second topic of this dissertation focuses on the investigation of light absorption by carbonaceous particles using PA. Optical absorption spectra of size and mass selected laboratory generated aerosols consisting of black carbon (BC), BC with non-absorbing coating (ammonium sulfate and sodium chloride) and BC with a weakly absorbing coating (brown carbon derived from humic acid) were measured across the visible to near-IR (500 nm to 840 nm). The manner in which BC mixed with each coating material was investigated. The absorption enhancement of BC was determined to be wavelength dependent. Optical absorption spectra were also taken for size and mass selected smoldering smoke produced from six types of commonly seen wood in a laboratory scale apparatus.

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Executing a cloud or aerosol physical properties retrieval algorithm from controlled synthetic data is an important step in retrieval algorithm development. Synthetic data can help answer questions about the sensitivity and performance of the algorithm or aid in determining how an existing retrieval algorithm may perform with a planned sensor. Synthetic data can also help in solving issues that may have surfaced in the retrieval results. Synthetic data become very important when other validation methods, such as field campaigns,are of limited scope. These tend to be of relatively short duration and often are costly. Ground stations have limited spatial coverage whilesynthetic data can cover large spatial and temporal scales and a wide variety of conditions at a low cost. In this work I develop an advanced cloud and aerosol retrieval simulator for the MODIS instrument, also known as Multi-sensor Cloud and Aerosol Retrieval Simulator (MCARS). In a close collaboration with the modeling community I have seamlessly combined the GEOS-5 global climate model with the DISORT radiative transfer code, widely used by the remote sensing community, with the observations from the MODIS instrument to create the simulator. With the MCARS simulator it was then possible to solve the long standing issue with the MODIS aerosol optical depth retrievals that had a low bias for smoke aerosols. MODIS aerosol retrieval did not account for effects of humidity on smoke aerosols. The MCARS simulator also revealed an issue that has not been recognized previously, namely,the value of fine mode fraction could create a linear dependence between retrieved aerosol optical depth and land surface reflectance. MCARS provided the ability to examine aerosol retrievals against “ground truth” for hundreds of thousands of simultaneous samples for an area covered by only three AERONET ground stations. Findings from MCARS are already being used to improve the performance of operational MODIS aerosol properties retrieval algorithms. The modeling community will use the MCARS data to create new parameterizations for aerosol properties as a function of properties of the atmospheric column and gain the ability to correct any assimilated retrieval data that may display similar dependencies in comparisons with ground measurements.

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To establish the prevalence of olfactory dysfunction in smoking and non-smoking students of our Faculty who attend the Department of Otolaryngology (ENT) of our Hospital. Materials and method: Students (smokers and non-smokers) that do and do not suffer from olfactory dysfunction. We applied a questionnaire and a pocket smell test for screening all of the students. Results: We evaluated 207 students, between 18 and 30 years old; 50.7% (n=105) were women and 49.3% (n=102) were men. The smokers among them smoked up to 6 packs per year. One hundred twenty three students were non-smokers and 84 students were smokers. Of the 84 students who were smokers, 67 (79.7%) answered the Pocket Smell Test correctly (3/3) and 17 (20.2%) students had one or more errors. We had 123 non-smoker students and 103 (83.7%) students answered the Pocket Smell Test correctly and 20 (16.2%) answered with one or more errors. The prevalence of olfactory dysfunction in young smokers with a 95% conidence interval would be 32.8%. Conclusions: This study informed us about olfactory dysfunctions in our student population and their smoking habits. We corroborate that the Pocket Smell Test is reliable with the questionnaire; nevertheless it is a screening test. We have a population of young people who smoke one cigarette per day and who didn’t have a signiicant alteration in their ability of smell at the time of the study. This is consistent with medical literature. More studies should be conducted in order to expand this information.