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1.
Glob Chang Biol ; 30(4): e17279, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619007

RESUMO

There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such as micro- and nanoplastic particles. Estimates of the environmental persistence of plastic pollution, and the formation of fragments, will need to take in account plastic dispersal around the globe, as well as projected UV radiation levels and climate change factors.


Assuntos
Energia Solar , Raios Ultravioleta , Raios Ultravioleta/efeitos adversos , Mudança Climática , Poluição Ambiental , Tempo (Meteorologia)
2.
Photochem Photobiol Sci ; 23(4): 629-650, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38512633

RESUMO

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment.


Assuntos
Plásticos , Poluentes Químicos da Água , Humanos , Plásticos/toxicidade , Ecossistema , Raios Ultravioleta , Mudança Climática , Poluentes Químicos da Água/análise
3.
Glob Chang Biol ; 27(22): 5681-5683, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34392574

RESUMO

The Montreal Protocol and its Amendments have been highly effective in protecting the stratospheric ozone layer, preventing global increases in solar ultraviolet-B radiation (UV-B; 280-315 nm) at Earth's surface, and reducing global warming. While ongoing and projected changes in UV-B radiation and climate still pose a threat to human health, food security, air and water quality, terrestrial and aquatic ecosystems, and construction materials and fabrics, the Montreal Protocol continues to play a critical role in protecting Earth's inhabitants and ecosystems by addressing many of the United Nations Sustainable Development Goals.


Assuntos
Perda de Ozônio , Ozônio , Mudança Climática , Ecossistema , Humanos , Ozônio Estratosférico , Raios Ultravioleta/efeitos adversos
4.
Acta Paediatr ; 110(5): 1516-1525, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33289955

RESUMO

AIM: To study the psychometric properties, reliability and validity of the FinDiab quality-of-life questionnaire (FDQL), a strength-oriented quality-of-life (QOL) questionnaire for children and adolescents with type 1 diabetes (T1D). METHODS: Participants were 215 youths with T1D (aged 10-17 years). They completed FDQL and comparison questionnaires (KINDL-R and SDQ). Demographic and disease measures were collected from the participants' medical records. The questionnaire's psychometric properties were investigated. Construct validity was studied through principal component analysis using Promax rotation, reliability with alphas, and criterion and convergent validity with correlations between sum scale, subscales, demographic and disease factors, and comparison measures. RESULTS: FDQL demonstrated an adequate range of measurement and feasibility. The four-factor solution was found to be optimal, resulting in the subscales of flexibility with diabetes, well-being, social relations and health behaviour. The sum scale correlated significantly with glycaemic control and the psychosocial and QOL comparison measures. Construct, criterion and convergent validity of the subscales was also good. Children under 14 years of age reported better QOL than older adolescents. CONCLUSION: FDQL is a practical QOL assessment method focusing on strengths. The questionnaire has good validity and reliability and is easy to use as a clinical tool.


Assuntos
Diabetes Mellitus , Qualidade de Vida , Adolescente , Criança , Finlândia , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
5.
Photochem Photobiol Sci ; 16(9): 1349-1370, 2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28848959

RESUMO

The UV Index was established more than 20 years ago as a tool for sun protection and health care. Shortly after its introduction, UV Index monitoring started in several countries either by newly acquired instruments or by converting measurements from existing instruments into the UV Index. The number of stations and networks has increased over the years. Currently, 160 stations in 25 European countries deliver online values to the public via the Internet. In this paper an overview of these UV Index monitoring sites in Europe is given. The overview includes instruments as well as quality assurance and quality control procedures. Furthermore, some examples are given about how UV Index values are presented to the public. Through these efforts, 57% of the European population is supplied with high quality information, enabling them to adapt behaviour. Although health care, including skin cancer prevention, is cost-effective, a proportion of the European population still doesn't have access to UV Index information.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36293991

RESUMO

We modelled the impact of selected meteorological factors on the daily number of new cases of the coronavirus disease 2019 (COVID-19) at the Hospital District of Helsinki and Uusimaa in southern Finland from August 2020 until May 2021. We applied a DLNM (distributed lag non-linear model) with and without various environmental and non-environmental confounding factors. The relationship between the daily mean temperature or absolute humidity and COVID-19 morbidity shows a non-linear dependency, with increased incidence of COVID-19 at low temperatures between 0 to -10 °C or at low absolute humidity (AH) values below 6 g/m3. However, the outcomes need to be interpreted with caution, because the associations found may be valid only for the study period in 2020-2021. Longer study periods are needed to investigate whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a seasonal pattern similar such as influenza and other viral respiratory infections. The influence of other non-environmental factors such as various mitigation measures are important to consider in future studies. Knowledge about associations between meteorological factors and COVID-19 can be useful information for policy makers and the education and health sector to predict and prepare for epidemic waves in the coming winters.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Incidência , Finlândia/epidemiologia , Conceitos Meteorológicos , Umidade , Temperatura , China/epidemiologia
8.
Photochem Photobiol ; 85(5): 1233-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19496987

RESUMO

UV radiation exerts several effects concerning life on Earth, and spectral information on the prevailing UV radiation conditions is needed in order to study each of these effects. In this paper, we present a method for reconstruction of solar spectral UV irradiances at the Earth's surface. The method, which is a further development of an earlier published method for reconstruction of erythemally weighted UV, relies on radiative transfer simulations, and takes as input (1) the effective cloud optical depth as inferred from pyranometer measurements of global radiation (300-3000 nm); (2) the total ozone column; (3) the surface albedo as estimated from measurements of snow depth; (4) the total water vapor column; and (5) the altitude of the location. Reconstructed daily cumulative spectral irradiances at Jokioinen and Sodankylä in Finland are, in general, in good agreement with measurements. The mean percentage difference, for instance, is mostly within +/-8%, and the root mean square of the percentage difference is around 10% or below for wavelengths over 310 nm and daily minimum solar zenith angles (SZA) less than 70 degrees . In this study, we used pseudospherical radiative transfer simulations, which were shown to improve the performance of our method under large SZA (low Sun).

9.
Plant Physiol Biochem ; 134: 40-52, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30219502

RESUMO

Evergreen plants in boreal biomes undergo seasonal hardening and dehardening adjusting their photosynthetic capacity and photoprotection; acclimating to seasonal changes in temperature and irradiance. Leaf epidermal ultraviolet (UV)-screening by flavonols responds to solar radiation, perceived in part through increased ultraviolet-B (UV-B) radiation, and is a candidate trait to provide cross-photoprotection. At Hyytiälä Forestry Station, central Finland, we examined whether the accumulation of flavonols was higher in leaves of Vaccinium vitis-idaea L. growing above the snowpack compared with those below the snowpack. We found that leaves exposed to colder temperatures and higher solar radiation towards the top of hummocks suffered greater photoinhibition than those at the base of hummocks. Epidermal UV-screening was highest in upper-hummock leaves, particularly during winter when lower leaves were beneath the snowpack. There was also a negative relationship between indices of flavonols and anthocyanins across all leaves suggesting fine-tuning of flavonoid composition for screening vs. antioxidant activity in response to temperature and irradiance. However, the positive correlation between the maximum quantum yield of photosystem II photochemistry (Fv/Fm) and flavonol accumulation in upper hummock leaves during dehardening did not confer on them any greater cross-protection than would be expected from the general relationship of Fv/Fm with temperature and irradiance (throughout the hummocks). Irrespective of timing of snow-melt, photosynthesis fully recovered in all leaves, suggesting that V. vitis-idaea has the potential to exploit the continuing trend for longer growing seasons in central Finland without incurring significant impairment from reduced duration of snow cover.


Assuntos
Fotossíntese/efeitos da radiação , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Estações do Ano , Raios Ultravioleta , Vaccinium vitis-Idaea/fisiologia , Vaccinium vitis-Idaea/efeitos da radiação , Flavonoides/metabolismo , Florestas , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentos Biológicos/metabolismo , Epiderme Vegetal/metabolismo , Neve , Solo , Temperatura , Fatores de Tempo
10.
Rev Sci Instrum ; 86(10): 103103, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26520936

RESUMO

Polystyrene and many other materials turn yellow when exposed to ultraviolet (UV) radiation. All photodegradation mechanisms including photoyellowing are functions of the exposure wavelength, which can be described with an action spectrum. In this work, a new high-resolution transmittance measurement setup based on lasers has been developed for measuring color changes, such as the photoyellowing of translucent materials aged with a spectrograph. The measurement setup includes 14 power-stabilized laser lines between 325 nm and 933 nm wavelengths, of which one at a time is directed on to the aged sample. The power transmitted through the sample is measured with a silicon detector utilizing an integrating sphere. The sample is mounted on a high-resolution XY translation stage. Measurement at various locations aged with different wavelengths of exposure radiation gives the transmittance data required for acquiring the action spectrum. The combination of a UV spectrograph and the new high-resolution transmittance measurement setup enables a novel method for studying the UV-induced ageing of translucent materials with a spectral resolution of 3-8 nm, limited by the adjustable spectral bandwidth range of the spectrograph. These achievements form a significant improvement over earlier methods.

11.
Rev Sci Instrum ; 82(2): 023107, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21361573

RESUMO

A facility for exploring wavelength dependencies in ultraviolet (UV) radiation induced degradation in materials has been designed and constructed. The device is essentially a spectrograph separating light from a lamp to spectrally resolved UV radiation. It is based on a 1 kW xenon lamp and a flat-field concave holographic grating 10 cm in diameter. Radiation at the wavelength range 250-500 nm is dispersed onto the sample plane of 1.5 cm in height and 21 cm in width. The optical performance of the device has been characterized by radiometric measurements. Using the facility, test samples prepared of regular newspaper have been irradiated from 1 to 8 h. Color changes on the different locations of the aged samples have been quantified by color measurements. Yellowness indices computed from the color measurements demonstrate the capability of the facility in revealing wavelength dependencies of the material property changes in reasonable time frames.

12.
J Sep Sci ; 28(4): 337-46, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15792248

RESUMO

LC-MS methods with use of ion-trap and time-of-flight mass spectrometers were developed for the determination of organic acids in aerosol samples collected by a high-volume sampler in a Finnish coniferous forest. Comparison was made of the composition of samples collected during atmospheric formation of new aerosol particles and on days when this formation did not occur. A dynamic sonication-assisted solvent extraction system was developed for fast and quantitative extraction of the filter samples. Several organic acids, including pinonic acid, pinic acid, and homologous series of n-alkanoic acids, n-alkenoic acids, and aliphatic dicarboxylic acids, were identified. In samples collected between 08:00 and 16:00 hours the concentration of pinonic acid ranged from 0.5 ng m(-3) to 3.7 ng m(-3) and that of pinic acid from 0.2 ng m(-3) to 1.5 ng m(-3). For most of the compounds identified, the trends in concentration could be explained by the differences in temperature during collection. However, concentrations of short-chain n-alkanoic acids were clearly higher on the days when new aerosol particle formation occurred.


Assuntos
Ácidos/análise , Ácidos/química , Aerossóis/análise , Aerossóis/química , Compostos Orgânicos/química , Árvores/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas
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