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1.
Medicina (Kaunas) ; 59(3)2023 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-36984453

RESUMEN

Background and Objectives: Myopia is the most common refractive eye anomaly with a prevalence that is constantly increasing. High myopia is associated with numerous complications that can lead to permanent vision loss. It is believed that the basis of these complications lies in changes in the microvasculature of the retina caused by an increase in the longitudinal axis of the eye. Materials and Methods: Optical coherence tomography angiography (OCTA) was used to analyze differences in macular zone vascular and perfusion density and foveal avascular zone (FAZ) parameters in myopic subjects. The following OCTA parameters were analyzed: the vessel and perfusion density of retinal blood vessels in the superficial plexus; the area, perimeter, and index of circularity of the foveal avascular zone (FAZ); and foveal and ganglion cell complex (GCC) thickness. Results: Subjects with low myopia did not show statistically significant differences compared to the control for any of the analyzed parameters. Groups with moderate and high myopia showed a significant decrease in vessel and perfusion density in the parafoveal and the entire 3 × 3 mm analyzed field. Foveal vessel and perfusion densities in the myopic groups were similar to those of the control regardless of the degree of myopia. The area and perimeter of the FAZ, as well as foveal and mean GCC thickness, did not differ significantly no matter the degree of myopia, while the index of circularity was lower in highly myopic subjects. The minimal thickness of the GCC was also lower in the high myopia group. Conclusions: High and moderate myopia led to a loss of blood vessels in the macular region. Perfusion and vascular densities were preserved in the foveal region and were not affected by different degrees of myopia. The FAZ was not significantly larger in myopic subjects, but its circularity was lower in subjects with high myopia.


Asunto(s)
Mácula Lútea , Miopía , Humanos , Angiografía con Fluoresceína/métodos , Mácula Lútea/diagnóstico por imagen , Mácula Lútea/irrigación sanguínea , Fóvea Central/diagnóstico por imagen , Fóvea Central/irrigación sanguínea , Vasos Retinianos/diagnóstico por imagen , Miopía/complicaciones , Tomografía de Coherencia Óptica/métodos
2.
Artículo en Inglés | MEDLINE | ID: mdl-36900886

RESUMEN

At the destination level, destination branding may coexist with climate change communication. These two communication streams often overlap because they are both designed for large audiences. This poses a risk to the effectiveness of climate change communication and its ability to prompt a desired climate action. The viewpoint paper advocates the use of archetypal branding approach to ground and center climate change communication at a destination level while concurrently maintaining the uniqueness of destination branding. Three archetypes of destinations are distinguished: villains, victims, and heroes. Destinations should refrain from actions that would make them appear to be climate change villains. A balanced approach is further warranted when portraying destinations as victims. Lastly, destinations should aim at assuming the heroic archetypes by excelling in climate change mitigation. The basic mechanisms of the archetypal approach to destination branding are discussed alongside a framework that suggests areas for further practical investigation of climate change communication at a destination level.


Asunto(s)
Cambio Climático , Coraje , Comunicación
3.
Sci Total Environ ; 653: 140-147, 2019 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-30408662

RESUMEN

Current research suggests that, apart from photochemical reactions, toluene, ethylbenzene and xylene (TEX) removal from ambient air might be affected by atmospheric precipitation, depending on the concentrations and water solubility of the compounds, Henry's law, physico-chemical properties of the water, as well as the frequency and intensity of precipitation events. Nevertheless, existing knowledge of the role that wet deposition plays in biogeochemical cycles of volatile species remains insufficient, and this topic requires more scientific effort to be explored and understood. In this study, we employed the eXtreme Gradient Boosting tree ensemble for revealing TEX transfer from ambient air to rainwater, and applied a novel SHapley Additive exPlanations feature attribution framework to examine the relevance of the monitored parameters and identify key factors that govern wet deposition of TEX. According to the results, main impacts, including ambient air TEX concentrations, and rainwater and air temperatures, and occasional, but less important impacts, including wind speed, air pressure, turbidity, and total organic carbon, NO3-, Cl- and K+ rainwater concentration, shaped TEX partition between gaseous and aqueous phases during rain events.

4.
Environ Monit Assess ; 145(1-3): 349-59, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18060512

RESUMEN

O(3), NO(2), SO(2), CO and PM(10) concentrations, simultaneously determined for the first time in Belgrade urban area in the autumnal period of 2005, are presented. The obtained results display similar behaviour of SO(2), NO(2), CO, PM(10) opposite from that of O(3). The weekend effect was also investigated showing diminution of average daily concentrations of SO(2), NO(2), PM(10) and CO for 72, 40, 37 and 42% respectively, and increase of the average daily concentration of O(3) for 56%. Influence of meteorological conditions on observed concentration levels was studied, too. The observed influence of wind speed on the O(3) nightly concentration levels was analyzed pointing to the phenomena of O(3) transport during episodic measurements. To make an identification of possible pollution sources and analyse the influence of meteorological parameters on pollution levels, air back trajectories for high level concentrations episodes were calculated and analysed. A multivariate receptor modelling (Principal Component Analysis, Cluster Analysis) has been applied to a set of data in order to determine the contribution of different sources. It was found that the main principal components, extracted from the air pollution data, were related to gasoline combustion, oil combustion and ozone transport.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monóxido de Carbono/análisis , Dióxido de Nitrógeno/análisis , Ozono/análisis , Tamaño de la Partícula , Dióxido de Azufre/análisis , Salud Urbana , Análisis por Conglomerados , Análisis Multivariante , Serbia
5.
Environ Sci Pollut Res Int ; 10(2): 89-97, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12729040

RESUMEN

This study has shown theoretical, observed and experimental evidence of pollutants released, transported and deposited during the Kosovo conflict in 1999 and their effects on precipitation in Serbia. The greatest bombardment of the chemical industry, oil refineries and fuel storage in Serbia which occurred during April, resulted in releases of many hazardous, toxic and cancerogenic substances. The number of April's days with precipitation greater or equal to 0.1 mm in 1999 are compared to those in the period from 1961 to 1990 registered at thirty meteorological stations in Serbia and especially at the Belgrade-Observatory station in the period from 1888 to 1995. The maximums of days with precipitation greater or equal to 0.1 mm were at the wider Belgrade area and at the central and southwestern parts of Serbia during April 1999. This is confirmed by using the Eta trajectory analysis.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Lluvia , Guerra , Aerosoles , Contaminantes Ambientales/análisis , Conceptos Meteorológicos , Tamaño de la Partícula , Hidrocarburos Policíclicos Aromáticos/análisis , Estaciones del Año , Yugoslavia
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