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Solar Exposure (solar + exposure)
Selected AbstractsObjective determination of fatigue development following sun exposure using Advanced Trail Making TestINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2004T. Horikoshi Synopsis Sun exposure during leisure activity evokes fatigue. We employed the Advanced Trail Making Test (ATMT), a recently developed objective method of evaluating brain function performance used to measure mental fatigue, for objective determination of fatigue development caused by solar exposure to the human body. First, a survey of consumer awareness was performed, and fatigue development from solar exposure was generally recognized in both summer and spring. In the field test, 15 males (26,41 years old) received sun exposure equivalent to 100 kJ m,2 of ultraviolet radiation three to four times each day for 3 days, during which the subjects wore a short sleeve shirt and a short pant, and covered their head with a towel. A significant increase in scores for subjective sense of fatigue was observed in the evening of all 3 days following sun exposure and on the fourth day, which had no exposure, as well as in the morning of the third and fourth days, as compared with those periods during the control week, which did not have experimental solar exposure. ATMT showed a significant increase in average value in the evening of the first and second days following sun exposure, as well as in the morning of the third and fourth days. In addition, increases in body temperature and heart rate were observed during the exposure periods. The results of multiple regression analysis of subjective feelings showed that fatigue caused by solar exposure was qualitatively different from that in the control week. These results suggest that brain function performance declined following solar exposure as did fatigue development. ATMT results may be useful for quantitative and objective evaluation of mental fatigue caused by sun exposure, along with development of sun care products for the prevention of solar-caused fatigue. Résumé L'exposition au soleil pendant les activités de loisir provoque la fatigue. Nous avons utilisé la méthode ,Advanced Trail Making Test (ATMT)', une méthode d'évaluation objective de la faculté du fonctionnement du cerveau, récemment développée pour mesurer la fatigue mentale, dans le but de déterminer objectivement le processus de la fatigue du corps humain causée par l'exposition au soleil. Premièrement, nous avons mené un sondage sur la conscience du consommateur, et une évolution de la fatigue venant de l'exposition au soleil a été notée dans l'ensemble au printemps et en été. Lors des expériences sur le terrain, 15 sujets mâles (de 26 à 41 ans) ont été exposés au soleil, 3 à 4 fois par jour, pendant 3 jours. L'exposition était égale à 100 kJ m,2 de radiation ultraviolette. Pendant ces 3 jours, les sujets étaient vêtus d'une chemize à manches courtes et d'un pantalon court, et avaient la tête couverte d'une serviette. Nous avons observé une augmentation considérable du score représentant la sensation subjective de fatigue le soir des 3 jours suivant l'exposition au soleil, et le soir du quatrième jour, sans exposition, de même que le matin des troisième et quatrième jours, en comparaison avec les mêmes périodes de la semaine de contrôle, sans exposition expérimentale au soleil. Les résultats du test de l'ATMT ont montré une augmentation considérable de la valeur moyenne le soir des premier et second jours suivant l'exposition au soleil, aussi bien que le matin des troisième et quatrième jours. De plus, nous avons observé une augmentation de la température du corps et du pouls pendant les moments d'exposition. L'analyse de régression multiple des résultats de la sensation subjective a montré que la fatigue causée par l'exposition était qualitativement différente que celle de la semaine de contrôle. Ces résultats suggèrent que la faculté de fonctionnement du cerveau baisse après l'exposition au soleil, comme le fait la fatigue. Les résultats de l'ATMT peuvent être utiles pour l'évaluation quantitative et objective de la fatigue mentale causée par l'exposition au soleil, ceci allant de pair avec le développement des produits de soin contre le soleil pour la prévention de la fatigue causée par le soleil. [source] Smoking, sun exposure, number of nevi and previous neoplasias are risk factors for melanoma in older patients (60 years and over)JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 1 2010E Nagore Abstract Background, Malignant melanoma risk factors have been studied in different geographical area populations. However, no study has focused on risk factors which are more frequently associated to the over 60's age group. Methods, A case-control study was performed that included 160 patients age , 60 years diagnosed of cutaneous melanoma and 318 controls matched for age and sex. Both groups were assessed, by personal interview and physical examination, for different phenotype characteristics (hair and eye color, phototype), the presence of other cutaneous lesions (solar lentigines, actinic keratoses and nevi), degree and type of solar exposure and personal and family past history of cutaneous or non-cutaneous cancer. Differences were evaluated by contingency tables and univariate and multivariate logistic regression. Results, Of 17 factors, those risk factors with a strong effect on the development of melanoma in the elderly were: fair eyes, severe sunburns, years of occupational sun exposure, smoking, > 50 melanocytic nevi and personal history of NMSC and other non-cutaneous neoplasias. Conclusions, Tobacco smoking is an independent risk factor for cutaneous melanoma in the elderly. Intense (both acute and chronic) sun exposure and constitutional features, such as tumor susceptibility (NMSC, non-cutaneous neoplasias, and multiple nevi) are also associated with melanoma risk. All these factors should help to better design educational campaigns in older people. [source] Bacterial Inactivation by Solar Ultraviolet Radiation Compared with Sensitivity to 254 nm RadiationPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 5 2009Thomas P. Coohill Our goal was to derive a quantitative factor that would allow us to predict the solar sensitivity of vegetative bacterial cells to natural solar radiation from the wealth of data collected for cells exposed to UVC (254 nm) radiation. We constructed a solar effectiveness spectrum for inactivation of vegetative bacterial cells by combining the available action spectra for vegetative cell killing in the solar range with the natural sunlight spectrum that reaches the ground. We then analyzed previous studies reporting the effects of solar radiation on vegetative bacterial cells and on bacterial spores. Although UVC-sensitive cells were also more sensitive to solar radiation, we found no absolute numerical correlation between the relative solar sensitivity of vegetative cells and their sensitivity to 254 nm radiation. The sensitivity of bacterial spores to solar exposure during both summer and winter correlated closely to their UVC sensitivity. The estimates presented here should make it possible to reasonably predict the time it would take for natural solar UV to kill bacterial spores or with a lesser degree of accuracy, vegetative bacterial cells after dispersion from an infected host or after an accidental or intentional release. [source] Photobleaching of Dissolved Organic Material from a Tidal Marsh-Estuarine System of the Chesapeake Bay,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2007Maria Tzortziou ABSTRACT Wetlands and tidal marshes in the Rhode River estuary of the Chesapeake Bay act as important sources of dissolved organic carbon and strongly absorbing dissolved organic matter (DOM) for adjacent estuarine waters. The effects of solar exposure on the photochemical degradation of colored DOM (CDOM) were examined for material derived from different sources (estuarine and freshwater parts of the Rhode River, sub-watershed stream, marshes) in this estuarine ecosystem. Consistent with changes in fluorescence emission, absorption loss upon exposure to different portions of the solar spectrum (i.e. different long-pass cut-off filters) occurred across the entire spectrum but the wavelength of maximum photobleaching decreased as the cut-off wavelength of the filter decreased. Our results illustrate that solar exposure can cause either an increase or a decrease in the CDOM absorption spectral slope, SCDOM, depending on the spectral quality of irradiation and, thus, on the parameters (e.g. atmospheric composition, concentration of UV-absorbing water constituents) that affect the spectral characteristics of the light to which CDOM is exposed. We derived a simple spectral model for describing the effects of solar exposure on CDOM optical quality. The model accurately, and consistently, predicted the observed dependence of CDOM photobleaching on the spectral quality of solar exposure. [source] Common Fluorescent Sunlamps are an Inappropriate Substitute for Sunlight ,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2000Douglas B. Brown ABSTRACT Fluorescent sunlamps are commonly employed as convenient sources in photobiology experiments. The ability of Kodacel to filter photobiologically irrelevant UVC wavelengths has been described. Yet there still remains a major unaddressed issue,the over representation of UVB in the output. The shortest terrestrial solar wavelengths reaching the surface are ,295 nm with the 295,320 nm range comprising ,4% of the solar UV irradiance. In Kodacel-filtered sunlamps, 47% of the UV output falls in this range. Consequently, in studies designed to understand skin photobiology after solar exposure, the use of these unfiltered sunlamps may result in misleading, or even incorrect conclusions. To demonstrate the importance of using an accurate representation of the UV portion of sunlight, the ability of different ultraviolet radiation (UVR) sources to induce the expression of a reporter gene was assayed. Unfiltered fluorescent sunlamps (FS lamps) induce optimal chloramphenicol acetyltransferase (CAT) activity at apparently low doses (10,20 J/cm2). Filtering the FS lamps with Kodacel raised the delivered dose for optimal CAT activity to 50,60 mJ/cm2. With the more solar-like UVA-340 lamps somewhat lower levels of CAT activities were induced even though the apparent delivered doses were significantly greater than for either the FS or Kodacel-filtered sunlamp (KFS lamps). When DNA from parallel-treated cells was analyzed for photoproduct formation by a radioimmuneassay, it was shown that the induction of CAT activity correlated with the level of induced photoproduct formation regardless of the source employed. [source] Effects of natural barriers on the spillover of a marine mollusc: implications for fisheries reservesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2003Alexander Tewfik Abstract 1.The movement of organisms and dispersal of propagules is fundamental to the maintenance of populations over time. However, the existence of barriers, created through the spatial configuration of habitats, may significantly affect dispersal patterns and thus influence community dynamics and resource sustainability. 2.Within marine environments unstructured or open habitats may form partial or complete ecological barriers due to elevated risk of predation or physical stresses associated with them. The existence and effects of such barriers may be of particular importance when considering the establishment of marine protected areas with a fisheries enhancement focus. 3.In this paper, the spillover of post-settlement queen conch (Strombus gigas) from a protected area in the Turks and Caicos Islands is investigated. It is hypothesized that the reserve boundaries overlap with a series of shallow, sand habitats that effectively enclose the protected population, reducing the spillover of conch into the adjacent fished areas. 4.To test this, density gradient maps for juvenile and adult conch populations were constructed using underwater visual survey data at 68 sites within and surrounding the protected area. These maps illustrate very low densities coinciding with poor, shallow sand habitats along the two marine boundaries of the reserve where spillover is expected to take place. 5.These sand habitats are thought to create ecological barriers to a slow, sedentary gastropod largely due to their shallowness (physical stresses of solar exposure or anoxia) and lack of food reducing the tendency of individuals to move across these areas, despite the 10-times higher density of adult queen conch observed in the protected area compared with outside. Copyright © 2003 John Wiley & Sons, Ltd. [source] Ultraviolet radiation exposure pattern in winter compared with summer based on time-stamped personal dosimeter readingsBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2006E. Thieden Summary Background, Personal annual ultraviolet (UV) radiation data based on daily records are needed to develop protective strategies. Objectives, To compare UV radiation exposure patterns in the winter half-year (October,March) and the summer half-year (April,September) for Danish indoor workers. Methods, Nineteen indoor workers (age range 17,56 years) wore personal UV dosimeters, measuring time-stamped UV doses continuously during a year. The corresponding sun exposure behaviour was recorded in diaries. Similar data were collected for 28 volunteers during sun holidays in the winter half-year. The relationship between UV dose and sun exposure behaviour was analysed. Results, The ambient UV dose during the winter in Denmark (at 56°N) was 394 standard erythema doses (SED) or 10·5% of the annual ambient UV dose. In winter compared with summer the subjects had: (i) a lower percentage of ambient UV radiation, 0·82% vs. 3·4%; (ii) a lower solar UV dose in Denmark, 3·1 SED (range 0·2,52) vs. 133 SED (range 69,363); (iii) less time outdoors per day with positive dosimeter measurements, 10 min vs. 2 h; and (iv) no exposure (0 SED) per day on 77% vs. 19% of the days. Sun holidays outside Denmark in winter gave a median 4·3 SED per day (range 0·6,7·6) and 26 SED (range 3,71) per trip. Conclusions, In the winter half-year indoor workers received a negligible UV dose from solar exposure in Denmark and needed no UV precautions. No UV precautions are needed from November to February during holidays to latitudes above 45 °N, while precautions are needed the whole year around at lower latitudes. [source] | |||||||||||||