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1.
J Gambl Stud ; 38(3): 917-939, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34518986

RESUMO

The present study is the first to examine account-based tracking data of Portuguese online lottery players comprising the gambling activity of all active players over a one-year period (N = 154,585). The main research goal was the identification of groups or segments of players by their engagement levels (high, neutral, low) and to assess preferences in product category with the use of CHAID (Chi-Square Automatic Interaction Detection) segmentation models, based on expenditure and sociodemographic variables. Findings showed that (1) age was found to be the most influential differentiating variable in player segmentation and had a positive correlation with expenditures and wagers, (2) gender was the second most influential variable (males represented 78.7% of players), (3) education the third most influential variable and had a negative correlation with expenditure, and (4) region was the least relevant variable. The models generated several players segments that engaged in different games. Older males (54-64 years; ≥ 65 years) were the most engaged overall. Younger males (18-34 years) were the least engaged but showed preferences for lotto as did females (35-49 years). Lower educated males and older males (49 years+) with a high school education were the most engaged in instant lottery games. These findings show that Portuguese lottery players can be grouped into several segments with distinct demographic characteristics and corresponding engagement levels. These findings help support more effective marketing segmentation and will help in the targeting of responsible gambling approaches.


Assuntos
Jogo de Azar , Etnicidade , Feminino , Jogo de Azar/psicologia , Humanos , Masculino , Marketing , Motivação , Portugal
2.
Comput Biol Med ; 123: 103917, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32768052

RESUMO

Intestinal parasites are responsible for several diseases in human beings. In order to eliminate the error-prone visual analysis of optical microscopy slides, we have investigated automated, fast, and low-cost systems for the diagnosis of human intestinal parasites. In this work, we present a hybrid approach that combines the opinion of two decision-making systems with complementary properties: (DS1) a simpler system based on very fast handcrafted image feature extraction and support vector machine classification and (DS2) a more complex system based on a deep neural network, Vgg-16, for image feature extraction and classification. DS1 is much faster than DS2, but it is less accurate than DS2. Fortunately, the errors of DS1 are not the same of DS2. During training, we use a validation set to learn the probabilities of misclassification by DS1 on each class based on its confidence values. When DS1 quickly classifies all images from a microscopy slide, the method selects a number of images with higher chances of misclassification for characterization and reclassification by DS2. Our hybrid system can improve the overall effectiveness without compromising efficiency, being suitable for the clinical routine - a strategy that might be suitable for other real applications. As demonstrated on large datasets, the proposed system can achieve, on average, 94.9%, 87.8%, and 92.5% of Cohen's Kappa on helminth eggs, helminth larvae, and protozoa cysts, respectively.


Assuntos
Parasitos , Animais , Humanos , Microscopia , Redes Neurais de Computação , Máquina de Vetores de Suporte
3.
Inhal Toxicol ; 31(3): 125-130, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-31179784

RESUMO

Objectives: The objective of this study was the evaluation of the professional exposure to nanoparticles during tasks performed in workstations for production of metallic parts by laser welding additive manufacturing. Materials and methods: The study was developed in an installed additive manufacturing machine, having controlled temperature and humidity in an industrial unit where metal parts were being produced using stainless steel powders of granulometry of 10 to 35 µm. Results and discussion: Monitoring of airborne nanoparticles emission was made using adequate equipment, which showed considerable number of nanoparticles over the baseline, having the same composition as the steel powder used. Conclusion: It is concluded that the values of professional exposure to nanoparticles are high in these workstations and that the nanoparticles to which the workers are exposed are small in size (around 15 nm), thus having a strong capacity for alveolar penetration and, consequently, with a strong possibility of passing to the bloodstream, accumulating in the body.


Assuntos
Poluentes Ocupacionais do Ar/análise , Nanopartículas/análise , Exposição Ocupacional/análise , Aço Inoxidável , Soldagem , Monitoramento Ambiental , Humanos , Pós
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 193: 212-218, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29247917

RESUMO

This paper reports the synthesis and the characterization of Yb3+-doped calcium borotellurite (CaBTeX) glasses with composition 10CaF2-(29.5-0.4x)CaO-(60-0.6x)B2O3-xTeO2-0.5Yb2O3 (x=10, 16, 22, 31 and 54mol%). The results of XRD confirm the amorphous character of all the samples. The density, molar volume, refractive index and electronic polarizability values show an increase with TeO2 content. Otherwise, the optical band gap energy shows a decrease with the increase of TeO2 content. The replacement of CaO and B2O3 by TeO2 changes the glass structure, which decreases the excited Yb3+/cm3 and, consequently, the luminescence intensity. The temperature dependence of luminescence was studied for all the samples up to 420K. The fluorescence lifetime does not change significantly due to TeO2 addition. In addition, absorption and emission cross section were calculated and present high values as compared to other tellurite and phosphate glasses.

5.
Inhal Toxicol ; 29(6): 282-289, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28805080

RESUMO

The primary objective of this study was to correlate the emission of macro and nanoparticles released during the process of metal inert gas/metal active gas (MIG/MAG) of stainless steel with different gas mixtures. Using different gas mixtures with different heat inputs, it was possible to determine fume formation rates and surface areas of nanoparticles with alveolar lung deposition capacity. It was found, how the various transfer modes and the type of gas protection, in particular, the percentage of active elements in the chemical composition of the gas, affect the amount of fumes generated and also the generation of nanoparticles with a high capacity of deposition. The spray transfer mode always shows higher values of nanoparticles surface area, unlike the fume formation rates. Among the tested mixtures 82%Ar + 18%CO2 generates higher emissions of nanoparticles as well as fume formation rates.


Assuntos
Poluentes Ocupacionais do Ar/análise , Nanopartículas/análise , Aço Inoxidável , Soldagem , Monitoramento Ambiental , Gases
6.
J Toxicol Environ Health A ; 80(13-15): 767-775, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28524808

RESUMO

The present study examined consequences of "safe" versus "critical" exposure to nanoparticles (NP) released during welding operations. With this aim in mind, a set of measurements regarding NP emissions was undertaken in a workshop during welding by metal active gas of carbon steel using different mixtures of argon (Ar) and carbon dioxide (CO2) as well as different process parameters which might influence emission of (NP). If these measurements were conducted in several locations away from the welding sources, the graphical representation of the obtained observations with time enabled definition of "safe" and "critical" regions within a welding workshop in terms of welder's exposure. This information may be combined with the results of risk analysis derived by control banding and helps to categorize the sites where regulatory measures such as operation containment or dedicated exhaust ventilation need to be implemented.


Assuntos
Nanopartículas/análise , Exposição Ocupacional/análise , Soldagem , Humanos , Nanopartículas/efeitos adversos , Exposição Ocupacional/efeitos adversos , Ventilação , Soldagem/normas
7.
J Toxicol Environ Health A ; 77(14-16): 867-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25072719

RESUMO

According to numerous studies, airborne nanoparticles have a potential to produce serious adverse human health effects when deposited into the respiratory tract. The most important parts of the lung are the alveolar regions with their enormous surface areas and potential to transfer nanoparticles into the blood stream. These effects may be potentiated in case of the elderly, since this population is more susceptible to air pollutants in general and more to nanoparticles than larger particles. The main goal of this investigation was to determine the exposure of institutionalized elders to nanoparticles using Nanoparticle Surface Area Monitor (NSAM) equipment to calculate the deposited surface area (DSA) of nanoparticles into elderly lungs. In total, 193 institutionalized individuals over 65 yr of age were examined in four elderly care centers (ECC). The occupancy daily pattern was achieved by applying a questionnaire, and it was concluded that these subjects spent most of their time indoors, including the bedroom and living room, the indoor microenvironments with higher prevalence of elderly occupancy. The deposited surface area ranged from 10 to 46 µm(2)/cm(3). The living rooms presented significantly higher levels compared with bedrooms. Comparing PM10 concentrations with nanoparticles deposited surface area in elderly lungs, it is conceivable that living rooms presented the highest concentration of PM10 and were similar to the highest average DSA. The temporal distribution of DSA was also assessed. While data showed a quantitative fluctuation in values in bedrooms, high peaks were detected in living rooms.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Monitoramento Ambiental/métodos , Habitação para Idosos , Nanopartículas/análise , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Material Particulado/análise
8.
J Toxicol Environ Health A ; 77(14-16): 924-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25072724

RESUMO

Friction stir welding (FSW) is now well established as a welding process capable of joining some different types of metallic materials, as it was (1) found to be a reliable and economical way of producing high quality welds, and (2) considered a "clean" welding process that does not involve fusion of metal, as is the case with other traditional welding processes. The aim of this study was to determine whether the emission of particles during FSW in the nanorange of the most commonly used aluminum (Al) alloys, AA 5083 and AA 6082, originated from the Al alloy itself due to friction of the welding tool against the item that was being welded. Another goal was to measure Al alloys in the alveolar deposited surface area during FSW. Nanoparticles dimensions were predominantly in the 40- and 70-nm range. This study demonstrated that microparticles were also emitted during FSW but due to tool wear. However, the biological relevance and toxic manifestations of these microparticles remain to be determined.


Assuntos
Poluentes Ocupacionais do Ar/análise , Ligas/química , Alumínio/química , Nanopartículas/química , Exposição Ocupacional/análise , Soldagem , Monitoramento Ambiental , Fricção
9.
Inhal Toxicol ; 26(6): 345-52, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24730680

RESUMO

This study is focused on the characterization of particles emitted in the metal active gas welding of carbon steel using mixture of Ar + CO2, and intends to analyze which are the main process parameters that influence the emission itself. It was found that the amount of emitted particles (measured by particle number and alveolar deposited surface area) are clearly dependent on the distance to the welding front and also on the main welding parameters, namely the current intensity and heat input in the welding process. The emission of airborne fine particles seems to increase with the current intensity as fume-formation rate does. When comparing the tested gas mixtures, higher emissions are observed for more oxidant mixtures, that is, mixtures with higher CO2 content, which result in higher arc stability. These mixtures originate higher concentrations of fine particles (as measured by number of particles by cm(3) of air) and higher values of alveolar deposited surface area of particles, thus resulting in a more severe worker's exposure.


Assuntos
Poluentes Ocupacionais do Ar/análise , Soldagem , Superfície Corporal , Humanos , Metais , Microscopia Eletrônica de Transmissão , Exposição Ocupacional , Tamanho da Partícula
10.
J Air Waste Manag Assoc ; 62(10): 1116-26, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23155858

RESUMO

UNLABELLED: Cooking was found to be a main source of submicrometer and ultrafine aerosols from gas combustion in stoves. Therefore, this study consisted of the determination of the alveolar deposited surface area due to aerosols resulting from common domestic cooking activities (boiling fish, vegetables, or pasta, and frying hamburgers and eggs). The concentration of ultrafine particles during the cooking events significantly increased from a baseline of 42.7 microm2/cm3 (increased to 72.9 microm2/cm3 due to gas burning) to a maximum of 890.3 microm2/cm3 measured during fish boiling in water and a maximum of 4500 microm2/cm3 during meat frying. This clearly shows that a domestic activity such as cooking can lead to exposures as high as those of occupational exposure activities. IMPLICATIONS: The approach of this study considers the determination of alveolar deposited surface area of aerosols generated from cooking activities, namely, typical Portuguese dishes. This type of measurement has not been done so far, in spite of the recognition that cooking activity is a main source of submicrometer and ultrafine aerosols. The results have shown that the levels of generated aerosols surpass the outdoor concentrations in a major European town, which calls for further determinations, contributing to a better assessment of exposure of individuals to domestic activities such as this one.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Culinária , Exposição por Inalação/análise , Poluentes Atmosféricos/química , Monitoramento Ambiental/métodos , Humanos , Pulmão/fisiologia , Modelos Biológicos , Tamanho da Partícula , Material Particulado/análise , Material Particulado/química , Portugal
11.
Inhal Toxicol ; 24(11): 774-81, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22954401

RESUMO

This article describes work performed on the assessment of the levels of airborne ultrafine particles emitted in two welding processes metal-active gas (MAG) of carbon steel and friction-stir welding (FSW) of aluminium in terms of deposited area in alveolar tract of the lung using a nanoparticle surface area monitor analyser. The obtained results showed the dependence from process parameters on emitted ultrafine particles and clearly demonstrated the presence of ultrafine particles, when compared with background levels. The obtained results showed that the process that results on the lower levels of alveolar-deposited surface area is FSW, unlike MAG. Nevertheless, all the tested processes resulted in important doses of ultrafine particles that are to be deposited in the human lung of exposed workers.


Assuntos
Poluentes Atmosféricos/química , Tamanho da Partícula , Material Particulado/química , Soldagem , Poluição do Ar em Ambientes Fechados
12.
J Air Waste Manag Assoc ; 62(4): 373-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22616279

RESUMO

The aim of this study was the assessment of exposure to ultrafine in the urban environment ofLisbon, Portugal, due to automobile traffic, and consisted of the determination of deposited alveolar surface area in an avenue leading to the town center during late spring. This study revealed differentiated patterns for weekdays and weekends, which could be related with the fluxes of automobile traffic. During a typical week, ultrafine particles alveolar deposited surface area varied between 35.0 and 89.2 microm2/cm3, which is comparable with levels reported for other towns such in Germany and the United States. These measurements were also complemented by measuring the electrical mobility diameter (varying from 18.3 to 128.3 nm) and number of particles that showed higher values than those previously reported for Madrid and Brisbane. Also, electron microscopy showed that the collected particles were composed of carbonaceous agglomerates, typical of particles emitted by the exhaustion of diesel vehicles.


Assuntos
Poluentes Atmosféricos/química , Exposição Ambiental/análise , Material Particulado/análise , Cidades , Monitoramento Ambiental , Humanos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Portugal , Fatores de Tempo , Emissões de Veículos
13.
Toxicol Mech Methods ; 21(8): 622-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21943233

RESUMO

A test chamber was projected and built (according to ISO 16000-9 Standard) to simulate atmospheric conditions experienced by rubber infill (when applied in synthetic turf pitches) and measure accurately the airborne emissions of pollutants such as dusts and volatile organic compounds (VOC), as well as pollutants present in leachates. It should be pointed out that standard ISO 16000-9 is only concerned with the determination of the emission of VOC from building products and furnishing (not specific of synthetic turf materials), whereas other standards are concerned with the emission of leachates only. This procedure is to be considered as a technical option to the lysimeter "global turf system evaluation" when the rubber infill alone is to be evaluated. The advantage of the proposed option considering this "test chamber" is its simplicity and economy. This test chamber is actually installed and being used for tests in LAIST.


Assuntos
Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Borracha/química , Borracha/toxicidade , Animais , Materiais de Construção , Monitoramento Ambiental , Teste de Materiais , Material Particulado/química , Reciclagem , Temperatura , Compostos Orgânicos Voláteis/química , Volatilização
14.
Spinal Cord ; 49(2): 206-10, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20625383

RESUMO

STUDY DESIGN: This is a retrospective study. OBJECTIVES: The aim of this study is to examine the main features and short-term neurological outcomes associated with injuries to the spine due to diving into water in a Latin American country. SETTING: Salvador, Brazil. PATIENT SAMPLE: A total of 1324 subjects were admitted with spinal trauma between 1991 and 2006 (inclusive). Subjects aged between 14 and 65 years who sustained diving injuries corresponded to 10.6% (N=140) of the cases. OUTCOME MEASURES: Neurological status was determined by the Frankel Functional Scale (FFS) on admission and discharge. The FFS was secondarily converted to the American Spinal Injury Association impairment scale. METHODS: This study is a patient record database review that examines demographic and injury-related characteristics, details of hospital treatment and neurological status at the time of discharge. RESULTS: Males (N=129) outnumbered females (N=11) in a proportion of 12:1 (mean age: 28.62 years). The cervical spine region was the most affected area (92.1%) and 45% of the cases presented with tetraplegia. On admission, neurologically complete lesions accounted for 32.1% of the overall cases and 45.7% were neurologically intact. The mean length of stay (7.7 weeks) did not differ with regard to treatment option (P=0.83). During hospitalization, patients with incomplete neurological impairment had shorter lengths of stay and showed more neurological improvement than those with complete lesions (P=0.26 and 64.5 versus 2.2%, P<0.0001). CONCLUSION: Diving spine injuries have a high tetraplegia rate. Neurological recovery and shorter length of stay are associated with incomplete lesions.


Assuntos
Traumatismos em Atletas/epidemiologia , Mergulho/lesões , Traumatismos da Medula Espinal/epidemiologia , Traumatismos da Medula Espinal/terapia , Traumatismos da Coluna Vertebral/epidemiologia , Traumatismos da Coluna Vertebral/terapia , Adolescente , Adulto , Idoso , Traumatismos em Atletas/terapia , Brasil/epidemiologia , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Quadriplegia/epidemiologia , Quadriplegia/terapia , Radiografia , Estudos Retrospectivos , Índice de Gravidade de Doença , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Adulto Jovem
15.
Environ Technol ; 31(1): 107-15, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20232684

RESUMO

Because of the adverse effect of CO2 from fossil fuel combustion on the earth's ecosystems, the most cost-effective method for CO2 capture is an important area of research. The predominant process for CO2 capture currently employed by industry is chemical absorption in amine solutions. A dynamic model for the de-absorption process was developed with monoethanolamine (MEA) solution. Henry's law was used for modelling the vapour phase equilibrium of the CO2, and fugacity ratios calculated by the Peng-Robinson equation of state (EOS) were used for H2O, MEA, N2 and O2. Chemical reactions between CO2 and MEA were included in the model along with the enhancement factor for chemical absorption. Liquid and vapour energy balances were developed to calculate the liquid and vapour temperature, respectively.


Assuntos
Poluentes Atmosféricos/química , Poluentes Atmosféricos/isolamento & purificação , Dióxido de Carbono/química , Dióxido de Carbono/isolamento & purificação , Conservação dos Recursos Naturais/métodos , Etanolamina/química , Modelos Químicos , Absorção , Simulação por Computador , Soluções
17.
Sci Total Environ ; 394(1): 197-205, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18291443

RESUMO

Fires of large dimension destroy forests, harvests and housing objects. Apart from that combustion products and burned surfaces become large ecological problems. Very often fires emerge simultaneously on different locations of a region so a question could be asked if they always have been a consequence of negligence, pyromania, high temperatures or maybe there has been some other cause. This paper is an attempt of establishing the possible connection between forest fires that numerous satellites registered and activities happening on the Sun immediately before fires ignite. Fires emerged on relatively large areas from Portugal and Spain on August 2005, as well as on other regions of Europe. The cases that have been analyzed show that, in every concrete situation, an emission of strong electromagnetic and thermal corpuscular energy from highly energetic regions that were in geo-effective position had preceded the fires. Such emissions have, usually, very high energy and high speeds of particles and come from coronary holes that also have been either in the very structure or in the immediate closeness of the geo-effective position. It should also be noted that the solar wind directed towards the Earth becomes weaker with deeper penetration towards the topographic surface. However, the results presented in this paper suggest that, there is a strong causality relationship between solar activity and the ignition of these forest fires taking place in South-western Europe.


Assuntos
Incêndios , Atividade Solar , Árvores , Portugal
18.
Chemosphere ; 44(5): 1011-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11513385

RESUMO

This paper describes work performed on the sampling and analysis of non-condensable gases (NCG) emitted from diffuse sources of a Portuguese Kraft pulp mill, which is the background information for a NCG collection, treatment and disposal system. The variability found in the composition of the gaseous compounds showed the existence of gaseous streams other than typical total reduced sulphur (TRS) compounds as usually described. From the measured TRS concentrations and the gas flow rate from each source it was possible to calculate the emission flow rate, E, of each source. These emission flow rates were then divided into three categories which are quite useful to identify significant sources and to choose abatement techniques. The methodology presented allows for a precise quantification of sources so that similar emissions can be grouped for treatment purposes. Sources with an emission flow rate bigger than 1 kg/h have a marked effect on the overall TRS emissions of the mill, as they are major contributors. It was also found that a new analytical procedure using Restek columns is more easy to use and overcomes operational problems noticed previously, namely a run time of 20-25 min instead of 50-60 min.


Assuntos
Poluentes Atmosféricos/análise , Compostos de Enxofre/análise , Movimentos do Ar , Monitoramento Ambiental , Gases , Incineração , Indústrias , Oxirredução , Papel
19.
J Air Waste Manag Assoc ; 51(1): 3-6, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11218423

RESUMO

This paper compares the calibration method for opacimeters issued by the International Standard Organization (ISO) 10155 with the manual reference method for determination of dust content in stack gases. ISO 10155 requires at least nine operational measurements, corresponding to three operational measurements per each dust emission range within the stack. The procedure is assessed by comparison with previous calibration methods for opacimeters using only two operational measurements from a set of measurements made at stacks from pulp mills. The results show that even if the international standard for opacimeter calibration requires that the calibration curve is to be obtained using 3 x 3 points, a calibration curve derived using 3 points could be, at times, acceptable in statistical terms, provided that the amplitude of individual measurements is low.


Assuntos
Poluição do Ar/análise , Monitoramento Ambiental/instrumentação , Calibragem , Análise de Regressão
20.
Sci Total Environ ; 208(1-2): 139-43, 1997 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-9496659

RESUMO

This paper describes systematic work done in the field of atmospheric emissions from Portuguese Kraft pulp mills. This study led to the determination of emission factors from stationary sources that proved to be an important tool in assessing the need for investment in air pollution abatement equipment.


Assuntos
Poluição do Ar/análise , Exposição Ambiental , Resíduos Industriais , Poluição do Ar/prevenção & controle , Humanos , Papel , Tamanho da Partícula , Portugal
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