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1.
Atherosclerosis ; 81(1): 19-31, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2407251

RESUMEN

To study the effects of long-term, self-monitored exercise on the serum lipid profile and body composition of middle-aged non-smoking males, a controlled study was conducted in 61 sedentary, middle-class Swiss men. Thirty-nine men were randomly allocated to jog 2 h/wk for 4 months on an individually prescribed, heart rate-controlled basis, whereas 22 men served as controls. Despite varying adherence to the exercise regimen, the following 4-month net changes (effect in exercise group minus effect in control group) in lipids were seen: HDL cholesterol (C) +0.12 mmol/l (95% CI 0.02, 0.22; P = 0.028), LDL-C +0.08 mmol/l (ns), VLDL-C -0.26 mmol/l (-0.45, -0.07; P = 0.009), total triglycerides (TT) -0.21 mmol/l (ns), HDL-C/total C +0.02 (0.001, 0.05; P = 0.047). The net changes in endurance capacity and resting heart rate in favour of exercisers were significant as well, whereas no significant changes in apolipoprotein levels were seen. Exploratory analyses revealed, for example, associations of the increase in total physical activity with an increase in the HDL-C/total C ratio (r = 0.46; P less than 0.001), and of the change in estimated body fat content with an opposed change in the HDL-C/total C ratio (r = -0.40; P less than 0.001), or an inverse relationship of the change in subcutaneous fat with a change in the HDL2-C level (r = -0.39; P less than 0.001). Multivariable regression analysis suggested that much of the effect of jogging on HDL-C was apparently mediated through a decrease in body fat content. A change in the waist/hip ratio was unrelated to lipoprotein changes but was related to the change of TT level (r = 0.22; P less than 0.05). This study confirms that individually prescribed, unsupervised jogging can increase HDL-C levels and improve the serum lipoprotein profile in self-selected nonsmoking males. Although the effect is modest, it may be relevant to preventive cardiology, given the evidence for a reduction in cardiovascular risk even after apparently small decreases in risk factor levels.


Asunto(s)
Apolipoproteínas/sangre , Ejercicio Físico , Lipoproteínas/sangre , Factores de Edad , Humanos , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad
2.
Atherosclerosis ; 75(2-3): 111-22, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2712856

RESUMEN

The relationship between serologic predictors of coronary risk and anthropometric as well as lifestyle characteristics was investigated in 61 men (37.5 +/- 8.5 yrs) and 33 women (40.1 +/- 9.0 yrs). All subjects were healthy non-smokers, mostly middle-class bank employees. In bivariate analysis, among both genders the ratio of waist-to-hip circumference (WHR) was the single best predictor of levels of serum LDL-cholesterol, apolipoprotein B, VLDL-cholesterol and triglycerides (positive association) as well as HDL-cholesterol and apolipoprotein A-I (inverse association). In men, body fat as estimated from bioelectrical impedance measurement was the second best predictor of lipoprotein and apoprotein concentrations, whereas in women it was the body mass index (BMI). The additional independent predictive power of WHR and body fat for the lipid profile was tested in multivariate analysis by adding WHR and body fat sequentially to regression models containing already BMI, endurance capacity, exercise, alcohol consumption and age. For example, explained variance of triglyceride distribution rose from 26.3 to 35.1% (P = 0.01 for increase) when body fat was entered into the regression equation, or inclusion of WHR into a model already containing age, the behavioral variables, BMI, and body fat increased the explained variance of LDL/HDL-cholesterol ratio from 20.9 to 27.6% (P = 0.04 for increase). In women, the same regression models were even slightly more predictive for the serum lipid profile. Endurance capacity was related to a low atherogenic risk lipid profile in bivariate analysis but lost much of its predictive power in multivariate analysis, which confirms that the effect of fitness on lipid levels is probably mediated in part by a low body fat content. It is concluded from this cross-sectional investigation that studies which focus on associations between lifestyle and serologic predictors of atherogenic risk should possibly include the WHR and a measure of body fat, since the latter two appear to be closer correlates of serum lipoprotein and apolipoprotein levels than BMI or single behavioral factors, at least among male non-smokers.


Asunto(s)
Antropometría , Apolipoproteínas/sangre , Estilo de Vida , Lipoproteínas/sangre , Tejido Adiposo/fisiología , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas , Colesterol/sangre , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resistencia Física , Factores Sexuales , Estadística como Asunto
3.
Anal Bioanal Chem ; 354(5-6): 763-9, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15067489

RESUMEN

Caesium sorption on Wyoming bentonite MX-80 has been studied in solutions of NaCl, KCl, MgCl(2), CaCl(2), NaNO(3) and Ca (NO(3))(2) of concentrations varying between 0.025 and 1 mol/L, as well as in a weakly saline (I=0.004 ml/L) and a strongly saline (I=0.46 mol/L) natural groundwater. These experiments have been used to derive a thermodynamic model for the interaction of caesium with the bentonite surface in accordance with a surface chemical model, including acid/base reactions developed recently for montmorillonite. The sorption behaviour of caesium on bentonite can be described, within the experimental and model uncertainties, in terms of a one-site ion exchange model. The ion exchange constant obtained for the reaction NaX+Cs(+) left arrow over right arrow CsX+Na(+) (where X represents the ion exchange sites on montmorillonite) is log(10) K(0)(ex)=1.6. Impurities in the bentonite, influencing the concentrations of competing cations, such as Na(+), K(+), Mg(2+) and Ca(2+), have a crucial impact on the sorption of caesium. This impact can be adequately quantified with the present model. The model predictions compare well with sorption data published in the open literature on both Wyoming bentonite MX-80 and other types of bentonite. Distribution coefficients from the literature obtained from both batch and diffusion experiments and varying over four orders of magnitude are reproduced and explained successfully by the model.

4.
Oecologia ; 12(3): 289-302, 1973 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-28308232

RESUMEN

Soil respiration was measured in different types of rain forest in West, South, and East Java, and in Sarawak, North Borneo. The altitude of the experimental sites varied from sea level to 1500 m. In keeping with the different amount and distribution of precipitation during the year, and due to the very different soil types, the vegetation varied from lowland to montane rain forest, teak forest, monsoon forest and heath forest. In all these forest types soil respiration values were of the same order of magnitude. They indicate an oxidation of 10 to 13 tons organic matter per hectar per year. In some of the experimental sites soil respiration was measured during the rainy as well as during the dry season. The values obtained justify extrapolation to a yearly average.The difficulties connected with interpretation of the soil respiration values as equivalent to net production of the different forest types have been discussed.

5.
Sci Total Environ ; 208(1-2): 15-21, 1997 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-9496645

RESUMEN

Among 17 homes in Switzerland, the relationship between indoor and outdoor levels for particulate matter less than 10 microns (PM10), particulate matter less than 2.5 microns (PM2.5) and NO2 was investigated. In 10 homes, the inhabitants also participated in conducting personal measurements. All homes were naturally ventilated. In homes without any indoor sources and where human activity was low, PM10 I/O ratios amounted to approximately 0.7. Of the indoor sources, smoking had the highest influence on I/O ratios (> 1.8). In homes not containing any apparent source, 'human activity' was an important factor accounting for high indoor levels. However, this factor is difficult to quantify. Personal exposure was in most cases higher than the indoor and the corresponding home outdoor levels. For NO2, gas-cooking was found to have the strongest influence on elevated I/O ratios (> 1.2) whilst for other homes, the I/O ratio was less than 1.


Asunto(s)
Contaminación del Aire Interior/análisis , Monitoreo del Ambiente , Dióxido de Nitrógeno/análisis , Exposición a Riesgos Ambientales , Vivienda , Humanos , Tamaño de la Partícula , Suiza
6.
Environ Pollut ; 91(1): 21-34, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-15091450

RESUMEN

During four intensive observation periods in 1992 and 1993, dry deposition of nitrogen dioxide (NO(2)) and ammonia (NH(3)), and wet deposition of nitrogen (N) were determined. The measurements were carried out in a small, extensively managed litter meadow surrounded by intensively managed agricultural land. Dry deposition of NH(3) was estimated by the gradient method, whereas eddy correlation was used for NO(2). Rates of dry deposition of total nitrate (= nitric acid (HNO(3)) + nitrate (NO(3)(-))), total nitrite (= nitrous acid (HONO) + nitrite (NO(2)(-))) and aerosol-bound ammonium (NH(4)(+)) were estimated using deposition velocities from the literature and measured concentrations. Both wet N deposition and the vertical NH(3) gradient were measured on a weekly basis during one year. Dry deposition was between 15 and 25 kg N ha(-1) y(-1), and net wet deposition was about 9.0 kg N ha(-1) y(-1). Daily average NO(2) deposition velocity varied from 0.11 to 0.24 cm s(-1). Deposition velocity of NH(3), was between 0.13 and 1.4 cm s(-1), and a compensation point between 3 and 6 ppbV NH(3) (ppb = 10(-9)) was found. Between 60 and 70% of dry deposition originated from NH(3) emitted by farms in the neighbourhood. It is concluded that total N deposition is exceeding the critical load for litter meadows, is highly correlated to local NH(3) emissions, and that NH(3) is of utmost importance with respect to possible strategies to reduce N deposition in rural regions.

7.
J Contam Hydrol ; 47(2-4): 283-96, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11288583

RESUMEN

A thermodynamic sorption model and a diffusion model based on electric double layer (EDL) theory are integrated to yield a surface chemical model that treats porewater chemistry, surface reactions, and the influence of charged pore walls on diffusing ions in a consistent fashion. The relative contribution of Stern and diffuse layer to the compensation of the permanent surface charge represents a key parameter; it is optimized for the diffusion of Cs in Kunipia-F bentonite, at a dry density of 400 kg/m3. The model is then directly used to predict apparent diffusivities (Da) of Cs, Sr, Cl-, I- and TcO4- and corresponding distribution coefficients (Kd) of Cs and Sr in different bentonites as a function of dry density, without any further adjustment of surface chemical and EDL parameters. Effective diffusivities (De) for Cs, HTO, and TcO4- are also calculated. All calculated values (Da, De, Kd) are fully consistent with each other. A comparison with published, measured data shows that the present model allows a good prediction and consistent explanation of (i) apparent and effective diffusivities for cations, anions, and neutral species in compacted bentonite, and of (ii) Kd values in batch and compacted systems.


Asunto(s)
Bentonita , Contaminantes del Agua/aislamiento & purificación , Adsorción , Difusión , Fenómenos Geológicos , Geología , Modelos Teóricos , Termodinámica , Contaminación del Agua/prevención & control
8.
Soz Praventivmed ; 25(6): 328-32, 1980 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-7245922

RESUMEN

The air quality inside of buildings depends on the contaminaton of the air outside as well as on the air pollution inside the room. The human being contaminates the air through carbon dioxide, odors, vapors and particulates. The most important sources of pollution are tobacco smoke (especially particulate matter, aldehydes and carbon monoxide), consumer materials (organic solvents), building materials and furniture fittings (Formaldehyd), as well as the use of gas for cooking and heating purposes (nitrogen oxides, carbon monoxide). More importance has to be attributed to the injurious effects of the various contaminants because of the reduced ventilation rate in order to save energy. When estimating the possible health damages and annoyances, the long-term effects have to be considered, thereby the increased sensibility of children, of ill and old people have to be taken into account. The health aspects are therefore a decisive criterium for guidelines concerning construction and minimum ventilation rates.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Contaminantes Atmosféricos/análisis , Vivienda , Humanos , Suiza , Ventilación
9.
Soz Praventivmed ; 21(2-3): 65-72, 1976.
Artículo en Alemán | MEDLINE | ID: mdl-61667

RESUMEN

The immediate source of air pollution is the fuel consumption that goes on in domestic heating (about 50%), in motor vehicles (about 25%), and in industry (about 25%). Immissions in towns and agglomerations do not only depend on the number and size of these issuing sources but also on the location and meteorological conditions. The average sulphur dioxide content in various towns amounts to 0.03-0.06 ppm in winter and in summer to 0.01-0.03 ppm. In weather conditions with little exchangeability, as is often the case in Zurich, particulate matter and sulphur dioxide concentrations frequently lie above threshold limits applied abroad. In the area of heavy traffic for instance, daily averages of carbon monoxide of up to 20 ppm, and maximum hourly averages of up to 50 ppm are measured--concentrations which lie also considerably above threshold limits. For nitrogen oxides, hydrocarbons and lead too, concentrations such as are measured in large foreign cities occur. In the future, coordinated time measurements will have to be carried out more frequently in Switzerland--especially in places with strong emitting sources and unfavorable meteorological conditions.


Asunto(s)
Contaminación del Aire/análisis , Monóxido de Carbono/análisis , Polvo , Humanos , Residuos Industriales , Estaciones del Año , Dióxido de Azufre/análisis , Suiza , Emisiones de Vehículos , Tiempo (Meteorología)
10.
Soz Praventivmed ; 27(2-3): 119-23, 1982 May.
Artículo en Alemán | MEDLINE | ID: mdl-7113466

RESUMEN

Annoyance is an important criterion to assess the health-impairing effects of noise. Affected are especially communications, due to speech interference, as well as relaxation and sleep. The extent of annoyance increases with rising noise load in the street traffic as well as in the air traffic. Air-traffic noise in residential areas should lie below NNI-values of 35; values of above 45 NNI result in a heavy noise load and require sound-protection measures. Street-traffic noise in residential areas should not surpass an Leq value of 60 dB(A) in daytime and 50 dB(A) at night; Leq values of more than 65 dB(A) are qualified as considerable annoyance and are thus critical. In recreation areas the threshold limits should be 5 dB(A) below these values, whereas for shops and offices at main thoroughfares values higher by 5 dB(A) can be tolerated. The noise load should first of all be diminished by stricter regulations for vehicles as well as by measures regarding traffic organization. Furthermore, noise-conscious driving is recommended. Very great traffic noise also requires sound protection measures.


Asunto(s)
Aeronaves , Automóviles , Ruido del Transporte , Ruido , Humanos , Estilo de Vida , Sueño
11.
Soz Praventivmed ; 31(1): 19-22, 1986.
Artículo en Alemán | MEDLINE | ID: mdl-3962497

RESUMEN

The measurements of atmospheric pollution carried out in Switzerland during the last years revealed that high concentrations are not only found in city centers but in suburbs as well. The emission limits which should be respected in order to protect health and environment are very often exceeded. The pollution through nitrogen dioxide is specially crucial as well as that of sulfur dioxide during the winter months. Ozone concentrations are remarkably high in summer--ozone being formed by photochemical reactions of nitrogen oxides and hydrocarbons--and can be transported far away, even in rural areas. It is urgent to take the necessary steps now to reduce the atmospheric pollution in order to protect the population against possible health damages.


Asunto(s)
Contaminación del Aire/análisis , Cadmio/análisis , Monóxido de Carbono/análisis , Polvo/análisis , Humanos , Plomo/análisis , Dióxido de Nitrógeno/análisis , Ozono/análisis , Salud Rural , Dióxido de Azufre/análisis , Suiza , Salud Urbana
12.
Soz Praventivmed ; 24(4): 282-3, 1979 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-539159

RESUMEN

Dilution threshold values were measured using sensory methods for an evaluation of odorous emissions of an incineration plant. The dispersion of odours was estimated based on recording of the local wind. The level of public annoyance in the neighbouring residential areas will be assessed by special questionnaires.


Asunto(s)
Eliminación de Residuos/métodos , Olfato , Humo
13.
Soz Praventivmed ; 26(3): 177-9, 1981 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-6794242

RESUMEN

In a test chamber of 30 m3 the air pollutants caused by man were measured. Variables were: number of persons and their activities and the rate of the air change. During test sessions of two hours the temperature, the relative humidity, the carbon dioxide and the intensity of odors were measured. There was a significant correlation between the odor intensities and the concentrations of carbon dioxide-independent of the number of persons and the air change rate. At air change rates of 12-15 m3 per person and per hour, the carbon dioxide concentration was not higher than 0.15% and the odor intensity was evaluated only as a slight annoyance. Further experiments were performed with physical activity and smoking.


Asunto(s)
Aire/análisis , Ventilación , Dióxido de Carbono/análisis , Humanos , Humedad , Odorantes/análisis , Temperatura
14.
Soz Praventivmed ; 32(4-5): 249-50, 1987.
Artículo en Alemán | MEDLINE | ID: mdl-3687220

RESUMEN

In a project of the International Energy Agency (IEA) called 'Minimum Ventilation Rates', factors relevant for indoor air quality are described. Based on these factors, recommendations to control indoor air Pollution are made.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/prevención & control , Humanos , Factores de Riesgo , Suiza , Ventilación
15.
Soz Praventivmed ; 27(5): 260-1, 1982 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-7158069

RESUMEN

Due to better insulation and airtight windows and doors, the supply of fresh air is reduced. Therefore the pollutants which are continuously emitted from different materials into the room air are considerably increased. Measurements of the formaldehyde concentrations in new buildings have shown that after a year the admissible limits are still exceeded. Stricter regulations are necessary to limit the emissions of building- and insulation materials.


Asunto(s)
Contaminación del Aire/análisis , Materiales de Construcción/efectos adversos , Exposición a Riesgos Ambientales , Formaldehído/análisis , Humanos , Instituciones Académicas
16.
Soz Praventivmed ; 21(4): 124-5, 1976.
Artículo en Francés | MEDLINE | ID: mdl-997955

RESUMEN

Indoor air quality affects a person's performance and well-being. This justifies the study of indoor air pollution for the development of comfortable and safe environments. A simultaneous indoor/outdoor sampling programme was carried out at three sites in Zurich. Parameters included CO, NO, NO2, and HCHO.


Asunto(s)
Contaminantes Atmosféricos/análisis , Vivienda , Benzopirenos/análisis , Monóxido de Carbono/análisis , Óxido Nítrico/análisis , Dióxido de Nitrógeno/análisis , Suiza
17.
Soz Praventivmed ; 22(3): 121-8, 1977.
Artículo en Francés | MEDLINE | ID: mdl-878656

RESUMEN

In January--February 1976 blood analyses were performed for two groups (rural and urban) of young girls aged 11--16 years. The following parameters were measured: PbB, ALAD, FEP, haemoglobin and hematocrit. Results indicate only low blood lead levels (PbB less than or equal to 20 microgram/100 ml: ALAD by European method greater than or equal to 33 U/1. A small but statistically significant difference was observed in case of rural/urban ALAD values.


Asunto(s)
Contaminación del Aire/análisis , Plomo/sangre , Adolescente , Niño , Salud Ambiental , Femenino , Hematócrito , Hemoglobinometría , Humanos , Intoxicación por Plomo/sangre , Concentración Máxima Admisible , Población Rural , Suiza , Población Urbana
18.
Soz Praventivmed ; 32(4-5): 251-2, 1987.
Artículo en Alemán | MEDLINE | ID: mdl-3687221

RESUMEN

Twelve healthy women and twelve healthy men were tested on an exercise bicycle until exhaustion in a climate chamber at ozone levels of 0, 0.06 and 0.12 ppm. Under high ozone, a clear decrease of performance was seen at maximal efforts as well as a shift of the anaerobic threshold to somewhat lower performance values. These changes are probably caused by increasingly difficult breathing due to a reflex bronchial constriction. At high ozone concentrations, further symptoms were recognized: itching in throat and neck region, thirst, fatigue and itching eyes.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Ozono/efectos adversos , Resistencia Física/efectos de los fármacos , Aptitud Física , Adulto , Relación Dosis-Respuesta a Droga , Prueba de Esfuerzo , Femenino , Humanos , Masculino
19.
Soz Praventivmed ; 23(4): 305-6, 1978 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-568365

RESUMEN

In order to obtain bases for the establishment of threshold values in the new environmental law, a random sample survey with 1600 persons in urban and rural areas has been made on the degree of disturbance by street traffic noice in the night.


Asunto(s)
Ritmo Circadiano , Ambiente , Ruido/efectos adversos , Transportes , Humanos , Calidad de Vida , Trastornos del Sueño-Vigilia/etiología , Suiza
20.
Soz Praventivmed ; 22(3): 108-15, 1977.
Artículo en Alemán | MEDLINE | ID: mdl-878654

RESUMEN

The residents of different streets with varying traffic density and building density were questioned about annoyance due to traffic noise and air pollution. Frequency and extent of annoyance felt, effects of immissions on such living aspects as recreation, or communication, and also the reactions to the disturbance felt (such as closing windows and taking sleeping pills) were investigated. Noise levels as well as particulate matter and gaseous air pollutant concentrations were measured along the streets under investigation. The evaluation of 1300 questionaires showed that reactions to noise were different in different quarters although noise levels were the same. In general, about 40% of residents were heavily disturbed during daytime when the noise level Leq was around 65 dB(A); while for the same noise level at night about 55% reported to be heavily disturbed. Strong correlations were also obtained between annoyance due to noise and that due to air pollution. The results show that annoyance felt is dependent not only on the measured noise levels and/or air pollution concentrations, but that there do exist interactions between the residential quarters and annoyance. These interactions should be considered while fixing the limits and standards.


Asunto(s)
Contaminación del Aire/análisis , Ruido/efectos adversos , Automóviles , Polvo , Vivienda , Humanos , Higiene , Encuestas y Cuestionarios , Suiza , Factores de Tiempo , Población Urbana
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