Ultraviolet Radiation
Mostrando 13-24 de 547 artigos, teses e dissertações.
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13. Vitamin D levels in actinic keratosis: a preliminary study
Abstract: Background: Recent studies that investigated the effect of vitamin D on skin cancer risk have exhibited inconsistent results. Objective: The aim of the study was to evaluate vitamin D status in patients with actinic keratosis. Methods: A cross-sectional study was conducted on 31 patients with actinic keratosis and 29 healthy controls. Serum vita
An. Bras. Dermatol.. Publicado em: 2018-08
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14. Evaluation of Fracture Toughness of Ultraviolet-Irradiated Polycarbonate Using the Essential Work of Fracture Method
The essential work of fracture (EWF) method provides useful parameters to characterize the fracture toughness of polymers exposed to degrading environments under conditions associated with plane-stress state of failure. Exposure of polymeric engineering materials to ultraviolet (UV) radiation may produce macromolecular changes that impair their fracture toug
Mat. Res.. Publicado em: 26/07/2018
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15. Photodegradation Mechanisms on Poly(ε-caprolactone) (PCL)
Photodegradation of PCL was performed exposing injected specimens to ultraviolet radiation (UV-B) up to 9 weeks. Photodegradated PCL specimens were tested by Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FTIR), mechanical properties, Optical Microscopy (MO) and Scanning Electron Microscopy (SEM).Upon exposure decrease in elongation at break
Mat. Res.. Publicado em: 16/07/2018
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16. UV-B radiation as an elicitor of secondary metabolite production in plants of the genus Alternanthera
ABSTRACT Ultraviolet B radiation has been described as a potential elicitor agent of the synthesis of secondary metabolites in plants. Thus, the present study aimed to investigate the production of betalains and total flavonoids, as well as the antioxidant activity, of Alternanthera sessilis, A. brasiliana, A. tenella and A. philoxeroides exposed to differen
Acta Bot. Bras.. Publicado em: 02/07/2018
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17. Biometrical and morphological analyses of Macrobrachium olfersii (Wiegmann, 1836) (Crustacea, Decapoda, Palaemonidae) embryos exposed to UVA and UVB radiation
ABSTRACT Macrobrachium olfersii (Wiegmann, 1836) is a prawn that lives in shallow and transparent freshwater in Southern Brazil. Aquatic organisms that inhabit these systems can be exposed to incident UV radiation. Many studies have demonstrated the effects of ultraviolet (UV) radiation on the development, survival rate, morphological abnormalities, and impa
Nauplius. Publicado em: 21/06/2018
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18. Blocking or enhancing effects of some basic emollients in UVA penetration
Abstract: Background: Topical agents used in combination with phototherapy or photochemotherapy may have both blocking or enhancing effects in ultraviolet rays. Objective: In this in vivo study, the effects of topical petrolatum, basis cream, glycerine, and olive oil on the transmission of ultraviolet A radiation were investigated. Methods: A test was per
An. Bras. Dermatol.. Publicado em: 2018-03
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19. Aging simulation of the tailings from Stava fluorite extraction by exposure to gamma rays
Abstract Tailings storage facilities are disposal systems for storing the waste products of the mining industry consisting of a slurry mixture made of soil, rock and water that remain after the mineral values have been removed from the patent ore. Tailings dams are supposed to last forever, so after their deposition, tailings can experience aging processes w
REM, Int. Eng. J.. Publicado em: 2017-12
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20. Molecular basis of basal cell carcinoma
Abstract: Basal cell carcinoma is the most common cancer, presenting low mortality but high morbidity, and it has as risk factor exposure to sunlight, especially UVB spectrum. The most important constitutional risk factors for basal cell carcinoma development are clear phototypes (I and II, Fitzpatrick classification), family history of basal cell carcinoma
An. Bras. Dermatol.. Publicado em: 2017-08
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21. Relationship between climatic factors and air quality with tuberculosis in the Federal District, Brazil, 2003-2012
Abstract Introduction: Despite the high rate of tuberculosis indicators in Brazil, the Federal District shows a low prevalence of the disease. Objective: To analyze the relationship between climatic factors and air quality with tuberculosis in the Brazilian Federal District. Methodology: This was an ecological and descriptive study comparing 3927 new case
Braz J Infect Dis. Publicado em: 2017-08
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22. Development and Characterization of Vitamin A-Loaded Solid Lipid Nanoparticles for Topical Application
Vitamin A and its esters are commonly found in topical applications because of their advantageous properties, however, have the drawback that are highly sensitive to ultraviolet radiation. The aim of this work was to develop and characterize a novel formulation of solid lipid nanoparticles suitable for topical applications in order to protect vitamin A from
J. Braz. Chem. Soc.. Publicado em: 2017-07
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23. Hydrolyzed collagen interferes with in vitro photoprotective effectiveness of sunscreens
ABSTRACT The chronological skin aging is a progressive and natural process with genetic and physiological changes. However, ultraviolet (UV) radiation may accelerate the oxidative stress, generating carcinogenesis and photoaging. Natural compounds and their applications are considered a trend in the cosmetic market. The protein-based film-forming compounds p
Braz. J. Pharm. Sci.. Publicado em: 22/06/2017
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24. Evaluation of a Thermochromic Liquid Crystal for Use as a Temperature Sensor for Components of Electrical Systems
Connectors used in electrical power distribution systems should allow the passage of electricity continuously and without interruption. However, this does not always occur due to failure caused by improper assembly and/or corrosion of the materials employed, which reflects the quality of service. Notable among the new detection technologies that have been st
Mat. Res.. Publicado em: 22/05/2017