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1.
Environ Model Softw ; 156: 105460, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36193100

RESUMEN

An operational urban air quality modelling system ENFUSER is presented with an evaluation against measured data. ENFUSER combines several dispersion modelling approaches, uses data assimilation, and continuously extracts information from online, global open-access sources. The modelling area is described with a combination of geographic datasets. These GIS datasets are globally available with open access, and therefore the model can be applied worldwide. Urban scale dispersion is addressed with a combination of Gaussian puff and Gaussian plume modelling, and long-range transport of pollutants is accounted for via a separate regional model. The presented data assimilation method, which supports the use of AQ sensors and incorporates a longer-term learning mechanism, adjusts emission factors and the regional background values on an hourly basis. The model can be used with reasonable accuracy also in urban areas, for which detailed emissions inventories would not be available, due to the data assimilation capabilities.

2.
Environ Res ; 214(Pt 2): 113798, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35810819

RESUMEN

A coordinated observational and modelling campaign targeting biogenic aerosols in the air was performed during spring 2021 at two locations in Northern Europe: Helsinki (Finland) and Siauliai (Lithuania), approximately 500 km from each other in north-south direction. The campaign started on March 1, 2021 in Siauliai (12 March in Helsinki) and continued till mid-May in Siauliai (end of May in Helsinki), thus recording the transition of the atmospheric biogenic aerosols profile from winter to summer. The observations included a variety of samplers working on different principles. The core of the program was based on 2- and 2.4--hourly sampling in Helsinki and Siauliai, respectively, with sticky slides (Hirst 24-h trap in Helsinki, Rapid-E slides in Siauliai). The slides were subsequently processed extracting the DNA from the collected aerosols, which was further sequenced using the 3-rd generation sequencing technology. The core sampling was accompanied with daily and daytime sampling using standard filter collectors. The hourly aerosol concentrations at the Helsinki monitoring site were obtained with a Poleno flow cytometer, which could recognize some of the aerosol types. The sampling campaign was supported by numerical modelling. For every sample, SILAM model was applied to calculate its footprint and to predict anthropogenic and natural aerosol concentrations, at both observation sites. The first results confirmed the feasibility of the DNA collection by the applied techniques: all but one delivered sufficient amount of DNA for the following analysis, in over 40% of the cases sufficient for direct DNA sequencing without the PCR step. A substantial variability of the DNA yield has been noticed, generally not following the diurnal variations of the total-aerosol concentrations, which themselves showed variability not related to daytime. An expected upward trend of the biological material amount towards summer was observed but the day-to-day variability was large. The campaign DNA analysis produced the first high-resolution dataset of bioaerosol composition in the North-European spring. It also highlighted the deficiency of generic DNA databases in applications to atmospheric biota: about 40% of samples were not identified with standard bioinformatic methods.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Atmósfera/análisis , Monitoreo del Ambiente/métodos , Europa (Continente) , Estaciones del Año
3.
Artículo en Inglés | MEDLINE | ID: mdl-33572804

RESUMEN

Urban dwellers are simultaneously exposed to several environmental health risk factors. This study aimed to examine the relationship between long-term exposure to fine particulate matter (PM2.5, diameter < 2.5 µm) of residential-wood-burning and road-traffic origin, road-traffic noise, green space around participants' homes, and hypertension. In 2015 and 2016, we conducted a survey of residents of the Helsinki Capital Region to determine their perceptions of environmental quality and safety, lifestyles, and health statuses. Recent antihypertensive medication was used as an indicator of current hypertensive illness. Individual-level exposure was estimated by linking residential coordinates with modelled outdoor levels of wood-smoke- and traffic-related PM2.5, road-traffic noise, and coverage of natural spaces. Relationships between exposure and hypertension were modelled using multi-exposure and single-exposure binary logistic regression while taking smooth functions into account. Twenty-eight percent of the participants were current users of antihypertensive medication. The odds ratios (95% confidence interval) for antihypertensive use were 1.12 (0.78-1.57); 0.97 (0.76-1.26); 0.98 (0.93-1.04) and 0.99 (0.94-1.04) for wood-smoke PM2.5, road-traffic PM2.5, road-traffic noise, and coverage of green space, respectively. We found no evidence of an effect of the investigated urban exposures on prevalent hypertension in the Helsinki Capital Region.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Hipertensión , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Exposición a Riesgos Ambientales/análisis , Finlandia/epidemiología , Humanos , Hipertensión/epidemiología , Hipertensión/etiología , Material Particulado/análisis
4.
Artículo en Inglés | MEDLINE | ID: mdl-31991910

RESUMEN

Marine traffic in harbors can be responsible for significant atmospheric concentrations of ultrafine particles (UFPs), which have widely recognized negative effects on human health. It is therefore essential to model and measure the time evolution of the number size distributions and chemical composition of UFPs in ship exhaust to assess the resulting exposure in the vicinity of shipping routes. In this study, a sequential modelling chain was developed and applied, in combination with the data measured and collected in major harbor areas in the cities of Helsinki and Turku in Finland, during winter and summer in 2010-2011. The models described ship emissions, atmospheric dispersion, and aerosol dynamics, complemented with a time-microenvironment-activity model to estimate the short-term UFP exposure. We estimated the dilution ratio during the initial fast expansion of the exhaust plume to be approximately equal to eight. This dispersion regime resulted in a fully formed nucleation mode (denoted as Nuc2). Different selected modelling assumptions about the chemical composition of Nuc2 did not have an effect on the formation of nucleation mode particles. Aerosol model simulations of the dispersing ship plume also revealed a partially formed nucleation mode (Nuc1; peaking at 1.5 nm), consisting of freshly nucleated sulfate particles and condensed organics that were produced within the first few seconds. However, subsequent growth of the new particles was limited, due to efficient scavenging by the larger particles originating from the ship exhaust. The transport of UFPs downwind of the ship track increased the hourly mean UFP concentrations in the neighboring residential areas by a factor of two or more up to a distance of 3600 m, compared with the corresponding UFP concentrations in the urban background. The substantially increased UFP concentrations due to ship traffic significantly affected the daily mean exposures in residential areas located in the vicinity of the harbors.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Ciudades , Finlandia , Modelos Teóricos , Navíos
5.
Artículo en Inglés | MEDLINE | ID: mdl-31416284

RESUMEN

Exposure to fine particles in ambient air has been estimated to be one of the leading environmental health risks in Finland. Residential wood combustion is the largest domestic source of fine particles, and there is increasing political interest in finding feasible measures to reduce those emissions. In this paper, we present the PM2.5 emissions from residential wood combustion in Finland, as well as the resulting concentrations. We used population-weighed concentrations in a 250 x 250 m grid as population exposure estimates, with which we calculated the disease burden of the emissions. Compared to a projected baseline scenario, we studied the effect of chosen reduction measures in several abatement scenarios. In 2015, the resulting annual average concentrations were between 0.5 and 2 µg/m3 in the proximity of most cities, and disease burden attributable to residential wood combustion was estimated to be 3400 disability-adjusted life years (DALY) and 200 deaths. Disease burden decreased by 8% in the 2030 baseline scenario and by an additional 63% in the maximum feasible reduction scenario. Informational campaigns and improvement of the sauna stove stock were assessed to be the most feasible abatement measures to be implemented in national air quality policies.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Material Particulado/efectos adversos , Material Particulado/análisis , Madera/efectos adversos , Madera/química , Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Finlandia , Humanos
6.
Lasers Surg Med ; 51(3): 223-229, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30614016

RESUMEN

OBJECTIVES: The primary objective of this study was to compare a traditional green KTP laser to a new investigational yellow laser (PhotoLase) in the treatment of facial telangiectasia in terms of the treatment outcomes. The secondary objective was to assess the functionality and reliability of the PhotoLase system from the perspective of the user. STUDY DESIGN/METHODS: The study was a randomized split-face double-blinded study that compared the treatment efficacy of the 532-nm KTP laser and the investigational 585-nm PhotoLase laser. One or two treatments were given based on the response of the first treatment. The improvement of telangiectasia was graded according to a 7-point Telangiectasia Grading Scale (TGS) by the subjects and blinded physicians. The subjects assessed the amount of pain during the treatments using Visual Analogue Scale (VAS), and evaluated adverse effects 2-3 days after the treatment(s) using a self-assessment form. RESULTS: At least 50% improvement was seen in 15/18 subjects after the first PhotoLase treatment, and a similar result was observed for KTP, as assessed by the blinded physicians (P = 0.29). In the subjects' assessment, 7/18 subjects had at least 50% improvement after the first PhotoLase treatment, whereas at least 50% improvement was observed for 10/18 subjects in the KTP side, the difference being significant (P = 0.008). The amount of pain was higher with PhotoLase compared to KTP (67.7 vs. 34.6, P < 0.001). There was no difference in the frequency of erythema, crusting or purpura between the devices, but more blistering and less edema were seen after PhotoLase treatment (P < 0.05). Treatment with PhotoLase was evaluated to be 4.7-fold faster than with KTP and the PhotoLase system was more compact, narrower, lighter, and easier to carry than KTP. CONCLUSIONS: The investigational PhotoLase laser enables significantly faster treatments, but the process is somewhat more painful than with KTP, otherwise providing a similar clinical outcome in the treatment of facial telangiectasia. Treatment Protocol Lasers Surg. Med. 51:223-229, 2019. © Wiley Periodicals, Inc.


Asunto(s)
Mejilla , Láseres de Semiconductores/uso terapéutico , Láseres de Estado Sólido/uso terapéutico , Terapia por Luz de Baja Intensidad , Telangiectasia/radioterapia , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Telangiectasia/diagnóstico por imagen , Telangiectasia/patología , Resultado del Tratamiento
7.
Artículo en Inglés | MEDLINE | ID: mdl-29649153

RESUMEN

Air pollution has been estimated to be one of the leading environmental health risks in Finland. National health impact estimates existing to date have focused on particles (PM) and ozone (O3). In this work, we quantify the impacts of particles, ozone, and nitrogen dioxide (NO2) in 2015, and analyze the related uncertainties. The exposures were estimated with a high spatial resolution chemical transport model, and adjusted to observed concentrations. We calculated the health impacts according to Word Health Organization (WHO) working group recommendations. According to our results, ambient air pollution caused a burden of 34,800 disability-adjusted life years (DALY). Fine particles were the main contributor (74%) to the disease burden, which is in line with the earlier studies. The attributable burden was dominated by mortality (32,900 years of life lost (YLL); 95%). Impacts differed between population age groups. The burden was clearly higher in the adult population over 30 years (98%), due to the dominant role of mortality impacts. Uncertainties due to the concentration-response functions were larger than those related to exposures.


Asunto(s)
Contaminantes Atmosféricos/economía , Contaminación del Aire/economía , Dióxido de Nitrógeno/economía , Ozono/economía , Material Particulado/economía , Adulto , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Exposición a Riesgos Ambientales/análisis , Exposición a Riesgos Ambientales/economía , Finlandia/epidemiología , Humanos , Modelos Químicos , Dióxido de Nitrógeno/análisis , Ozono/análisis , Material Particulado/análisis , Años de Vida Ajustados por Calidad de Vida , Riesgo , Análisis Espacial
8.
Duodecim ; 131(4): 396-8, 2015.
Artículo en Finés | MEDLINE | ID: mdl-26237932

RESUMEN

Reduction of male pattern hairiness--especially facial hairiness--is important for the identity of a transsexual female. Methods of treatment include epilation, waxing, chemical depilation, planing, electrolysis, eflornitine cream and methods based on optical light. Also the hormonal therapies utilized in the treatment process reduce the degree of hairiness and make the hairs thinner. Instead of hair removal, one should rather speak of reducing hairiness, since life-long hairlessness is usually not achieved even by the most effective methods of hair reduction. Aspects affecting the choice of treatment include skin type, quality of hair, tolerability and availability of treatment, among other things.


Asunto(s)
Remoción del Cabello/métodos , Hirsutismo/terapia , Personas Transgénero , Femenino , Humanos , Masculino
9.
Sci Total Environ ; 409(7): 1266-76, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21276603

RESUMEN

In this paper we propose a methodology consisting of specific computational intelligence methods, i.e. principal component analysis and artificial neural networks, in order to inter-compare air quality and meteorological data, and to forecast the concentration levels for environmental parameters of interest (air pollutants). We demonstrate these methods to data monitored in the urban areas of Thessaloniki and Helsinki in Greece and Finland, respectively. For this purpose, we applied the principal component analysis method in order to inter-compare the patterns of air pollution in the two selected cities. Then, we proceeded with the development of air quality forecasting models for both studied areas. On this basis, we formulated and employed a novel hybrid scheme in the selection process of input variables for the forecasting models, involving a combination of linear regression and artificial neural networks (multi-layer perceptron) models. The latter ones were used for the forecasting of the daily mean concentrations of PM10 and PM2.5 for the next day. Results demonstrated an index of agreement between measured and modelled daily averaged PM10 concentrations, between 0.80 and 0.85, while the kappa index for the forecasting of the daily averaged PM10 concentrations reached 60% for both cities. Compared with previous corresponding studies, these statistical parameters indicate an improved performance of air quality parameters forecasting. It was also found that the performance of the models for the forecasting of the daily mean concentrations of PM10 was not substantially different for both cities, despite the major differences of the two urban environments under consideration.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Redes Neurales de la Computación , Material Particulado/análisis , Atmósfera/química , Finlandia , Grecia , Modelos Químicos , Tamaño de la Partícula , Análisis de Componente Principal
10.
Sci Total Environ ; 409(8): 1559-71, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21277004

RESUMEN

Forecasting models based on stepwise multiple linear regression (MLR) have been developed for Athens and Helsinki. The predictor variables were the hourly concentrations of pollutants (NO, NO(2), NO(x), CO, O(3), PM(2.5) and PM(10)) and the meteorological variables (ambient temperature, wind speed/direction, and relative humidity) and in case of Helsinki also Monin-Obukhov length and mixing height of the present day. The variables to be forecasted are the maximum hourly concentrations of PM(10) and NO(x), and the daily average PM(10) concentrations of the next day. The meteorological pre-processing model MPP-FMI was used for computing the Monin-Obukhov length and the mixing height. The limitations of such statistical models include the persistence of both the meteorological and air quality situation; the model cannot account for rapid changes (on a temporal scale of hours or less than a day) that are commonly associated, e.g., with meteorological fronts, or episodes of a long-range transport origin. We have selected the input data for the model from one urban background and one urban traffic station both in Athens and Helsinki, in 2005. We have used various statistical evaluation parameters to analyze the performance of the models, and inter-compared the performance of the predictions for both cities. Forecasts from the MLR model were also compared to those from an Artificial Neural Network model (ANN) to investigate, if there are substantial gains that might justify the additional computational effort. The best predictor variables for both cities were the concentrations of NO(x) and PM(10) during the evening hours as well as wind speed, and the Monin-Obukhov length. In Athens, the index of agreement (IA) for NO(x) ranged from 0.77 to 0.84 and from 0.69 to 0.72, in the warm and cold periods of the year. In Helsinki, the corresponding values of IA ranged from 0.32 to 0.82 and from 0.67 to 0.86 for the warm and cold periods. In case of Helsinki the model accuracy was expectedly better on the average, when Monin-Obukhov length and mixing height were included as predictor variables. The models provide better forecasts of the daily average concentration, compared with the maximum hourly concentration for PM(10). The results derived by the ANN model where only slightly better than the ones derived by the MLR methodology. The results therefore suggest that the MLR methodology is a useful and fairly accurate tool for regulatory purposes.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Monitoreo del Ambiente/métodos , Óxidos de Nitrógeno/análisis , Material Particulado/análisis , Atmósfera/química , Finlandia , Predicción , Grecia , Modelos Químicos , Tamaño de la Partícula , Análisis de Regresión , Estaciones del Año
11.
Acta Derm Venereol ; 86(4): 329-31, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16874418

RESUMEN

People frequently experience whealing and delayed papules from mosquito bites. Various antihistamines have previously been tried for the treatment of this condition. We performed a double-blind, placebo-controlled, cross-over study with levocetirizine 5 mg and matched placebo in 30 adults who were sensitive to mosquito bites. On the third treatment day the subjects received two Aedes aegypti bites on the forearm. The size of the bite lesions and the intensity of pruritus (visual analogue scale) were measured. Bite symptoms could be analysed in 28 subjects at 15 min and in 8 subjects at 24 h. Levocetirizine decreased the size of wheals by 60% (p < 0.001) and accompanying pruritus by 62% (p < 0.001) compared with placebo. The effect of levocetirizine increased in a linear fashion with the size of wheals and was most significant in the subjects with largest bite lesions. Levocetirizine also decreased the size of 24-h bite lesions by 71% (p=0.008) and accompanying pruritus by 56% (p=0.016). These results show that prophylactic levocetirizine 5 mg is an effective treatment for both immediate and delayed mosquito bite symptoms and is especially effective in subjects with large wheals.


Asunto(s)
Aedes , Cetirizina/uso terapéutico , Antagonistas de los Receptores Histamínicos H1 no Sedantes/uso terapéutico , Hipersensibilidad Tardía/tratamiento farmacológico , Hipersensibilidad Inmediata/tratamiento farmacológico , Mordeduras y Picaduras de Insectos/inmunología , Piperazinas/uso terapéutico , Adulto , Animales , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Mordeduras y Picaduras de Insectos/patología , Masculino , Persona de Mediana Edad , Prurito/etiología , Prurito/patología , Prurito/prevención & control
12.
Scand J Work Environ Health ; 30 Suppl 2: 47-53, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15487685

RESUMEN

OBJECTIVES: This study attempted to develop a simple statistical model for assessing the contribution of aerosols transported regionally and those transported long range to the concentrations of fine particulate matter (PM2.5) in urban air in Helsinki. METHODS: The construction and testing of the linear regression model was based on PM2.5 measurement data from two locations in the City of Helsinki (Vallila & Kallio) and on ion concentration data obtained from the three nearest monitoring stations of The Co-operative Programme for Monitoring and Evaluating of the Long-range Transmission of Air Pollutants in Europe (EMEP). The "ion sum" was calculated on the basis of the following daily measured EMEP parameters in 1998--2000: (i) sulfate (SO4(2-)), (ii) the sum of nitrate (NO3-) and nitrogen acid (HNO3), and (iii) the sum of ammonium (NH4+) and ammonia (NH3). The ion sum was compared with sulfate as the proxy variable for PM2.5 transported long range. RESULTS: The correlation of the daily average PM2.5 concentration with the ion sum (R2=0.59-0.61) was higher than that with sulfate (R2 = 0.48-0.50). The regression estimates showed relatively small year-to-year variation. The contribution of long-range transport to the measured PM2.5 concentration in urban air in Helsinki was estimated to be 64-76%. CONCLUSIONS: The results showed a strong association between the ion sum interpolated from the EMEP data and the PM2.5 concentration measured at urban sites in Helsinki. This association can be utilized in local dispersion modeling of the PM2.5 concentration in urban air.


Asunto(s)
Contaminantes Atmosféricos/análisis , Polvo/análisis , Amoníaco/análisis , Finlandia , Humanos , Modelos Lineales , Modelos Teóricos , Nitratos/análisis , Nitrógeno/análisis , Compuestos de Amonio Cuaternario/análisis , Sulfatos/análisis , Transportes , Salud Urbana/normas , Salud Urbana/estadística & datos numéricos
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