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1.
Sci Total Environ ; 832: 155152, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413353

RESUMO

Surface urban heat islands (SUHIs) are an important socio-environmental problem associated with large cities, such as the Santiago Metropolitan Area (SMA), in Chile. Here, we analyze daytime and nighttime variations of SUHIs for each season of the year during the period 2000-2020. To evaluate socioeconomic inequities in the distribution of SUHIs, we establish statistical relationships with socioeconomic status, land price, and urban vegetation. We use the MODIS satellite images to obtain the land surface temperatures and the normalized difference vegetation index (NDVI) through the Google Earth Engine platform. The results indicate more intense SUHIs during the nighttime in the eastern sector, coinciding with higher socioeconomic status and larger green areas. This area during the day is cooler than the rest of the city. The areas with lower and middle socioeconomic status suffer more intense SUHIs (daytime and nighttime) and match poor environmental and urban qualities. These results show the high segregation of SMA. Urban planning is subordinated to land prices with a structure maintained over the study period. The lack of social-climate justice is unsustainable, and such inequalities may be exacerbated in the context of climate change. Thus, these results can contribute to the planning of the SMA.


Assuntos
Monitoramento Ambiental , Temperatura Alta , Chile , Cidades , Monitoramento Ambiental/métodos , Fatores Socioeconômicos
2.
Artigo em Inglês | MEDLINE | ID: mdl-34299859

RESUMO

BACKGROUND: Several countries have documented the relationship between long-term exposure to air pollutants and epidemiological indicators of the COVID-19 pandemic, such as incidence and mortality. This study aims to explore the association between air pollutants, such as PM2.5 and PM10, and the incidence and mortality rates of COVID-19 during 2020. METHODS: The incidence and mortality rates were estimated using the COVID-19 cases and deaths from the Chilean Ministry of Science, and the population size was obtained from the Chilean Institute of Statistics. A chemistry transport model was used to estimate the annual mean surface concentration of PM2.5 and PM10 in a period before the current pandemic. Negative binomial regressions were used to associate the epidemiological information with pollutant concentrations while considering demographic and social confounders. RESULTS: For each microgram per cubic meter, the incidence rate increased by 1.3% regarding PM2.5 and 0.9% regarding PM10. There was no statistically significant relationship between the COVID-19 mortality rate and PM2.5 or PM10. CONCLUSIONS: The adjusted regression models showed that the COVID-19 incidence rate was significantly associated with chronic exposure to PM2.5 and PM10, even after adjusting for other variables.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Chile/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Humanos , Incidência , Mortalidade , Pandemias , Material Particulado/análise , SARS-CoV-2
3.
Santiago; Centro del Clima y la Resiliencia; Sept. 2021. 68 p. ilus.
Não convencional em Espanhol | LILACS | ID: biblio-1418165

RESUMO

El presente documento tiene por objetivo mostrar los resultados del Piloto de Riesgo integrado de Asentamientos humanos, realizado en la Conurbación Valparaíso-Viña del Mar por el Equipo Asentamientos Humanos en el marco del proyecto ARClim. El objetivo del piloto fue construir y validar una metodología para evaluar riesgos en asentamientos humanos frente a múltiples amenazas climáticas. Utilizando de base el marco teórico-metodológico descrito en el working package de asentamientos humanos del proyecto ARCLim (Urquiza et al., 2020) donde se expone una definición integral para abordar el concepto de Riesgo, se construyeron 5 cadenas de impactos relevantes para la población con sus respectivos mapas de amenaza, exposición, sensibilidad y riesgo a escala subcomunal (manzana censal).


Assuntos
Humanos , Assentamentos Humanos , Controle de Cheias , Riscos Ambientais , Incêndios Florestais/prevenção & controle
4.
Int J Pharm ; 602: 120611, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33872710

RESUMO

The levitation of samples in an acoustic field has been of interest in the preparation and study of amorphous solid dispersions (ASD). Here, niclosamide-polymer solutions were levitated in a multi-emitter single-axis acoustic levitator and analyzed for 10 min at a High-resolution synchrotron X-ray powder diffraction beamline. This assembly enabled high-quality and fast time-resolved measurements with microliter sample size and measurement of solvent evaporation and recrystallization of niclosamide (NCL). Polymers HPMCP-55S, HPMCP-50, HPMCP-55, Klucel®, and poloxamers were not able to form amorphous dispersions with NCL. Plasdone® and Soluplus® demonstrated excellent properties to form NCL amorphous dispersions, with the last showing superior solubility enhancement. Furthermore, this fast levitation polymer screening showed good agreement with results obtained by conventional solvent evaporation screening evaluated for five days in a stability study, carried out at 40 °C/75% RH. The study showed that acoustic levitation and high-resolution synchrotron combination opens up a new horizon with great potential for accelerating ASD formulation screening and analysis.


Assuntos
Niclosamida , Síncrotrons , Acústica , Química Farmacêutica , Pós , Solubilidade , Difração de Raios X , Raios X
5.
Sci Total Environ ; 706: 135894, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31841846

RESUMO

Wildfires are gaining importance in the Mediterranean regions owing to climate change and landscape changes due to the increasing closeness between urban areas and forests prone to wildfires. We analysed the dry season wildfire occurrences in the Mediterranean region of Central Chile (32°S-39°30' S) between 2000 and 2017, using satellite images to detect burned areas, their landscape metrics and the land use and covers (vegetal) pre-wildfire, in order to determine the population living in areas that may be affected by wildfires. The existing regulations in western Mediterranean countries (Portugal, Spain, France, and Italy) were used to identify and define the wildland-urban interface (WUI) areas, quantifying the people inhabiting them and estimating the population affected by burned areas from 2001 to 2017. We used the Google Earth Engine to process MODIS products and extract both burned areas and land covers. We detected that 25% of the urban population inhabits WUI areas (i.e. Biobío, Araucanía and Valparaíso regions) where the urban population exposed to burned areas exceeds 40%. Most of the land use and land covers affected by wildfires are anthropogenic land covers, classified as savannas, croplands, evergreen broadleaf forests and woody savannas, representing >70% of the burned areas. Urban areas show only 0.6% of the burned surface from 2001 to 2017. We estimate that 55,680 people are potentially affected by wildfires, and 50% of them are in just one administrative region. These results show the imperative need for public policies as a regulating force for establishing WUI areas with the purpose of identifying wildfire risk in urban areas, such as establishing prevention methods as firewalls and prescribed fires.


Assuntos
Incêndios Florestais , Chile , Conservação dos Recursos Naturais
6.
J Pharm Sci ; 97(7): 2619-36, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17876767

RESUMO

The utility of thermal inkjet (TIJ) technology for preparing solid dosage forms of drugs was examined. Solutions of prednisolone in a solvent mixture of ethanol, water, and glycerol (80/17/3 by volume) were dispensed onto poly(tetrafluoroethylene)-coated fiberglass films using TIJ cartridges and a personal printer and using a micropipette for comparison. The post-dried, TIJ-dispensed samples were shown to contain a mixture of prednisolone Forms I and III based on PXRD analyses that were confirmed by Raman analyses. The starting commercial material was determined to be Form I. Samples prepared by dispensing the solution from a micropipette initially showed only Form I; subsequent Raman mapping of these samples revealed the presence of two polymorphs. Raman mapping of the TIJ-dispensed samples also showed both polymorphs. The results indicate that the solvent mixture used in the dispensing solution combined with the thermal treatment of the samples after dispensing were likely the primary reason for the generation of the two polymorphs. The advantages of using a multidisciplinary approach to characterize drug delivery systems are demonstrated using solid state mapping techniques. Both PXRD and Raman spectroscopy were needed to fully characterize the samples. Finally, this report clarifies prednisolone's polymorphic nomenclature existent in the scientific literature.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Prednisolona , Tecnologia Farmacêutica , Formas de Dosagem , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Prednisolona/administração & dosagem , Prednisolona/química , Impressão , Solubilidade , Solventes/química , Análise Espectral Raman , Propriedades de Superfície , Suspensões , Tecnologia Farmacêutica/instrumentação , Tecnologia Farmacêutica/métodos , Termodinâmica , Difração de Raios X
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