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1.
Environ Res ; 126: 204-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23747157

RESUMEN

This paper presents the extremely high concentrations of SO2 and particulate matter measured in the urban area of the town Bor (Serbia) during August 2011. Concentrations of SO2 above 125 µg m(-3) and concentrations of particulate matter above 200 µg m(-3) recorded over several days indicate significant risk to human health and the ecosystem in this region.


Asunto(s)
Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Dióxido de Azufre/análisis , Ciudades , Serbia
2.
An Acad Bras Cienc ; 84(1): 219-33, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22441612

RESUMEN

Selecting the best mining method among many alternatives is a multicriteria decision making problem. The aim of this paper is to demonstrate the implementation of an integrated approach that employs AHP and PROMETHEE together for selecting the most suitable mining method for the "Coka Marin" underground mine in Serbia. The related problem includes five possible mining methods and eleven criteria to evaluate them. Criteria are accurately chosen in order to cover the most important parameters that impact on the mining method selection, such as geological and geotechnical properties, economic parameters and geographical factors. The AHP is used to analyze the structure of the mining method selection problem and to determine weights of the criteria, and PROMETHEE method is used to obtain the final ranking and to make a sensitivity analysis by changing the weights. The results have shown that the proposed integrated method can be successfully used in solving mining engineering problems.

3.
J Environ Manage ; 91(2): 509-15, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19833429

RESUMEN

The results of multi-criteria ranking of copper concentrates by their quality, according to their content of useful and harmful components, are presented in this paper. Cu, Ag and Au were taken as useful components, while Pb, Zn, As, Cd, Hg, Bi and Sb were considered as harmful with adequate weight parameters. Considering its specific role in copper metallurgy, sulfur in the concentrate was considered in two scenarios. In the first scenario S was considered as a useful and in the other one as a harmful component. The ranking is done by implementing the PROMETHEE/GAIA method with an additional implementation of the special PROMETHEE V method, using the standard limitations of the heavy metals content in the concentrate. In this way, it is possible to perform an optimization of the input charge for the copper extraction from two aspects. The first aspect covers benefits from the content of useful metals, while the second deals with the protection of the environment, considering the content of harmful components of the charge. Using multi-criteria decision making for the sake of ranking the quality of copper concentrates, as described in this paper, could be considered as a contribution to the methodology of forming the market price of this product.


Asunto(s)
Conservación de los Recursos Naturales , Cobre/análisis , Contaminantes Ambientales/análisis , Metalurgia , Serbia
4.
Pflege Z ; 61(7): 400-3, 2008 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-18678151

RESUMEN

In modern patient interprofessional communication is an impor tant factor of good outcome. The aim of this study was to analyse the intercommunication during ward rounds and information passed by patients' documentation on an internal and geriatric medicine ward. Beside frequent interruptions the ward rounds showed a restricted flow of information that is based and targeted on the chief physician Nursing staff felt excluded from the informational flow. Regarding patients' documentation staff complained about lack of information and illegible notes. Availability of written information was found to be problematic. A team-orientated approach could help to improve interprofessional communication in the future. Besides the importance of carefully performed documentation as a reliable form of communication, communicative contribution of the nursing staff has to be upvalued.


Asunto(s)
Conducta Cooperativa , Documentación/métodos , Comunicación Interdisciplinaria , Registros de Enfermería , Relaciones Médico-Enfermero , Anciano , Enfermería Geriátrica , Humanos , Medicina Interna
5.
J Air Waste Manag Assoc ; 55(1): 3-12, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15704535

RESUMEN

The testing re-entrained aerosol kinetic emissions from roads technique is compared with distance-based emission factors (EFs; g/VKT) measured downwind of a dirt road by using towers instrumented with real-time meteorological and particle sensors at multiple heights. The emission potential (EP), defined as the EF divided by the vehicle speed (m/sec), and weight index permits the intercomparison of emissions from multiple roadways surveyed by the TRAKER vehicle. A survey of 72 km of unpaved roads on the Ft. Bliss Military Base near El Paso, Texas, indicated that 60% of all measured EPs fell between 6.7 (g/VKT)/(m/sec) and 9.6 (g/VKT)/(m/sec). The EP measured across the base was approximately 50% lower than those collected in the vicinity of the instrumented towers. This implies that EFs measured for other vehicles on the same test section should be reduced by 50% to more accurately represent EFs for the entire military base. Using geographic information system-based soil maps, the inferred EFs are related to differences in soil types over the survey area. Variations among five different soil types accounted for <10% of variation in EP. Individual measurements using the testing re-entrained aerosol kinetic emissions from roads technique did show larger spatial variations in EP; however, these were not effectively captured by the soil classifications, partly because of the comparatively coarse spatial classification used in the soil survey data.


Asunto(s)
Aerosoles/análisis , Sistemas de Información Geográfica , Contaminantes del Suelo/análisis , Emisiones de Vehículos/análisis , Recolección de Datos , Monitoreo del Ambiente , Cinética , Sensibilidad y Especificidad , Texas
6.
Sci Total Environ ; 322(1-3): 123-37, 2004 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-15081743

RESUMEN

A novel light detection and ranging-based remote sensing system was assembled and used to measure mass particulate matter (PM) emissions per unit of fuel burned from in-use on-road vehicles. A commercially available remote sensing system was concurrently used to measure emissions of carbon monoxide (CO), nitrogen oxide (NO) and hydrocarbons (HC). The two systems were used to measure 61,207 gasoline and 1180 diesel powered vehicle emissions in Las Vegas, NV from 4/4/2000 to 5/16/2002. Emission factors were related to vehicle age, weight class and fuel type by matching license IDs to the state registration data. Measurements of vehicle speed and acceleration permitted the analysis of emission factors by vehicle specific power (VSP). Average emission factors were calculated for light-duty (<3863 kg [8500 lbs]) gasoline vehicles (LDGV), light-duty diesel vehicles (LDDV), heavy-duty (>3863 kg [8500 lbs]) gasoline vehicles (HDGV) and heavy-duty diesel vehicles (HDDV). LDDV and HDDV emitted approximately 25 times more PM per mass of fuel than LDGV and HDGV. Sufficient numbers of LDGV were measured to relate VSP with CO, HC and NO emissions. No relationship was observed between PM emissions and VSP. PM emission factors from LDGV increased with vehicle age. Fuel-based emission factors measured by remote sensing were compared with MOBILE6 and PART5 emissions model factors. Good agreement was observed for HC emission factors for vehicles less than 20 years old. MOBILE6 CO emission factors were approximately 2 times greater than measured CO emission factors for vehicles less than 13 years old. Measured NO emission factors were approximately 50% greater than MOBILE6 factors for vehicles 7-15 years old but in good agreement for vehicles less than 7 years old. Measured PM emission factors showed a clear increase with vehicle age, however, PART5 uses only a single PM emission factor for LDGV less than 18 years old. The PM emission factors for the fleet of LDGV, HDGV, LDDV and HDDV were 0.06, 0.05, 1.6 and 1.5 g/kg, respectively.

7.
J Air Waste Manag Assoc ; 54(9): 1099-111, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15468663

RESUMEN

This work was motivated by the need to better reconcile emission factors for fugitive dust with the amount of geologic material found on ambient filter samples. The deposition of particulate matter with aerodynamic diameter less than or equal to 10 microm (PM10), generated by travel over an unpaved road, over the first 100 m of transport downwind of the road was examined at Ft. Bliss, near El Paso, TX. The field conditions, typical for warm days in the arid southwestern United States, represented sparsely vegetated terrain under neutral to unstable atmospheric conditions. Emission fluxes of PM10 dust were obtained from towers downwind of the unpaved road at 7, 50, and 100 m. The horizontal flux measurements at the 7 m and 100 m towers indicated that PM10 deposition to the vegetation and ground was too small to measure. The data indicated, with 95% confidence, that the loss of PM10 between the source of emission at the unpaved road, represented by the 7 m tower, and a point 100 m downwind was less than 9.5%. A Gaussian model was used to simulate the plume. Values of the vertical standard deviation sigma(z) and the deposition velocity Vd were similar to the U.S. Environmental Protection Agency (EPA) ISC3 model. For the field conditions, the model predicted that removal of PM10 unpaved road dust by deposition over the distance between the point of emission and 100 m downwind would be less than 5%. However, the model results also indicated that particles larger than 10 microm (aerodynamic diameter) would deposit more appreciably. The model was consistent with changes observed in size distributions between 7 m and 100 m downwind, which were measured with optical particle counters. The Gaussian model predictions were also compared with another study conducted over rough terrain and stable atmospheric conditions. Under such conditions, measured PM10 removal rates over 95 m of downwind transport were reported to be between 86% and 89%, whereas the Gaussian model predicted only a 30% removal. One explanation for the large discrepancy between measurements and model results was the possibility that under the conditions of the study, the dust plume was comparable in vertical extent to the roughness elements, thereby violating one of the model assumptions. Results of the field study reported here and the previous work over rough terrain bound the extent of particle deposition expected to occur under most unpaved road emission scenarios.


Asunto(s)
Contaminantes Atmosféricos/análisis , Polvo , Modelos Teóricos , Monitoreo del Ambiente , Tamaño de la Partícula , Estados Unidos
8.
J Air Waste Manag Assoc ; 54(6): 711-26, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15242151

RESUMEN

During the spring and summer of 2000, 2001, and 2002, gaseous and particulate matter (PM) fuel-based emission factors for approximately 150,000 low-tailpipe, individual vehicles in the Las Vegas, NV, area were measured via on-road remote sensing. For the gaseous pollutants (carbon monoxide, hydrocarbons, and nitrogen oxide), a commercial vehicle emissions remote sensing system (VERSS) was used. The PM emissions were determined using a Lidar-based VERSS. Emission distributions and their shapes were analyzed and compared with previous studies. The large skewness of the distributions is evident for both gaseous pollutants and PM and has important implications for emission reduction policies, because the majority of emissions are attributed to a small fraction of vehicles. Results of this Las Vegas study and studies at other geographical locations were compared. The gaseous pollutants were found to be close to those measured by VERSS in other U.S. cities. The PM emission factors for spark ignition and diesel vehicles are in the range of previous tunnel and dynamometer studies.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Nevada , Emisiones de Vehículos/análisis
9.
Water Air Soil Pollut ; 206(1-4): 369-383, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20098513

RESUMEN

This work presents the results of 4 years long monitoring of concentrations of SO(2) gas and PM(10) in the urban area around the copper smelter in Bor. The contents of heavy metals Pb, Cd, Cu, Ni, and As in PM(10) were determined and obtained values were compared to the limit values provided in EU Directives. Manifold excess concentrations of all the components in the atmosphere of the urban area of the townsite Bor were registered. Through application of a multi-criteria analysis by using PROMETHEE/GAIA method, the zones were ranked according to the level of pollution.

10.
Am J Physiol Cell Physiol ; 291(1): C68-75, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16495370

RESUMEN

Coordinated cell movements in epithelial layers are essential for proper tissue morphogenesis and homeostasis, but our understanding of the mechanisms that coordinate the behavior of multiple cells in these processes is far from complete. Recent experiments with Madin-Darby canine kidney epithelial monolayers revealed a wave-like pattern of injury-induced MAPK activation and showed that it is essential for collective cell migration after wounding. To investigate the effects of the different aspects of wounding on cell sheet migration, we engineered a system that allowed us to dissect the classic wound healing assay. We studied Madin-Darby canine kidney sheet migration under three different conditions: 1) the classic wound healing assay, 2) empty space induction, where a confluent monolayer is grown adjacent to a slab of polydimethylsiloxane and the monolayer is not injured but allowed to migrate upon removal of the slab, and 3) injury via polydimethylsiloxane membrane peel-off, where an injured monolayer migrates onto plain tissue culture surface, as in the case of empty space induction allowing for direct comparison. By tracking the motion of individual cells within the sheet under these three conditions, we show how the dynamics of the individual cells' motion is responsible for the coordinated migration of the sheet and is coordinated with the activation of ERK1/2 MAPK. In addition, we demonstrate that the propagation of the waves of MAPK activation depends on the generation of reactive oxygen species at the wound edge.


Asunto(s)
Células Epiteliales/fisiología , Modelos Biológicos , Cicatrización de Heridas/fisiología , Animales , Línea Celular , Movimiento Celular/fisiología , Perros , Células Epiteliales/citología , Células Epiteliales/enzimología , Quinasas de Proteína Quinasa Activadas por Mitógenos/fisiología , Estrés Mecánico
11.
J Theor Biol ; 221(2): 259-67, 2003 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-12628232

RESUMEN

The tunably rugged NK-model is used to study avalanche-like events that occur when environmental change causes fitness optima to disappear. The probability of an event with Delta substitutions scales as exp(-c Delta) for smooth landscapes, and as exp(-c Delta(2)) for rugged landscapes. Increasing the ruggedness leads to two competing effects: (1) more possible routes by which single mutations can increase the fitness, which dominates at low ruggedness and acts to increase Delta; and (2) a higher density of fitness optima, which dominates at high ruggedness and acts to decrease Delta. Due to these competing effects, the largest average values of Delta occur at intermediate ruggedness. The effects of system size on the avalanche events are examined, and average values of Delta increase logarithmically with system size. The variance to mean ratios for the number of substitutions per unit time are consistent with experimental results for protein evolution.


Asunto(s)
Ambiente , Evolución Molecular , Modelos Genéticos , Proteínas/genética , Animales , Biología Computacional , Simulación por Computador , Mutación
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