UVR: sun, lamps, pigmentation and vitamin D

Lerche, Catharina M.; Philipsen, Peter Alshede; Wulf, Hans Christian

doi:10.1039/c6pp00277c

Cited by 37 publications

(45 citation statements)

References 66 publications

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“…Last but not the least, the ultimate goal is to develop NB‐UVB LED light sources, which are strongly needed for the specific real‐world applications, such as those in immunotherapy, for vulgaris treatment, and plant lightning . A small part of the NB‐UVB spectrum can be used to treat skin conditions such as psoriasis and eczema .…”

Section: Resultsmentioning

confidence: 99%

“…Low cost, smart, safe, and low power consumption aluminium gallium nitride (AlGaN)‐based ultraviolet‐B light‐emitting diodes (UVB LEDs), compared with the other UV light sources including toxic mercury UV‐Lamps, are needed for real‐world applications, such as those in immunotherapy (psoriasis, vitiligo), vulgaris treatment, plant growth under UVB lightning, the production of vitamin D 3 in the human body, and the production of phytochemicals in green leaves of vegetables . Based on these motivations, we began our research and development of AlGaN‐based UVB LED devices to be grown on aluminum nitride (AlN) template, with medical science (294–310 nm) as well as agricultural applications (310 nm) in mind . However, the existence of high threading dislocation densities (TDDs ≈10 10 cm −2 ) in the AlGaN buffer layer (BL) grown on sapphire substrate, which is caused by large lattice mismatch ≈16% at the interface of sapphire substrate and BL, have presented a big challenge for many researchers .…”

Section: Introductionmentioning

confidence: 99%

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Influence of Undoped‐AlGaN Final Barrier of MQWs on the Performance of Lateral‐Type UVB LEDs

Khan

Matsuura

Kashima

et al. 2019

Physica Status Solidi (a)

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Aluminium gallium nitride (AlGaN)‐based ultraviolet‐B light‐emitting diodes (UVB LEDs) are expected to offer smart size, wider choice of UVB light emission in the wavelengths range of 280 nm > λ > 320 nm, and low cost as well as low power consumption compared with other UV light sources including toxic mercury UV‐lamps. The hole‐tunneling from p‐AlGaN side of UVB LED into the multi‐quantum‐wells (MQWs) is strongly dependent on the thickness (TFB) and Al‐contents of undoped (ud)‐AlGaN final barrier (FB). Herein, the photoluminescence (PL) efficiency from MQWs of the UVB LED devices is investigated and compared with the electroluminescence (EL) spectra as a function of TFB. Subsequently, the dependence of PL efficiency, external quantum efficiency (EQE), and light output power on the TFB of UVB LEDs is attempted, using the same growth condition for all samples except variation in TFB. When TFB is set to 6–7 nm, improvements in the EQE and light output power, respectively, from 4.3% and 7 mW to the high values of 5.6% and 17 mW in emission band of 295–300 nm under continuous‐wave (cw) at room temperature (RT) are achieved.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Influence of Undoped‐AlGaN Final Barrier of MQWs on the Performance of Lateral‐Type UVB LEDs

Khan

Matsuura

Kashima

et al. 2019

Physica Status Solidi (a)

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“…We found no association between ethnics and vitamin D levels for CF group. It is known the influence of skin pigmentation for the absorption of the UVB radiation and the photosynthesis of vitamin D . Subjects with type II skin pigmentation (white) have absorption of 20‐30% of the radiation, while subjects with type V skin pigmentation (black) absorb 2‐5%.…”

Section: Discussionmentioning

confidence: 99%

“…Seasonality was taken into consideration when analyzing vitamin D levels. Summer and spring were considered periods with higher sun incidence, and winter and fall were considered as lower sun incidence months . Parents and legal guardians were questioned about the children's sun exposure habits, according to the Brazilian Pediatric Society recommendations.…”

Section: Methodsmentioning

confidence: 99%

Lung disease and vitamin D levels in cystic fibrosis infants and preschoolers

Oliveira¹,

Matsunaga²,

Rodrigues³

et al. 2019

Pediatric Pulmonology

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Introduction: Vitamin D acts on the immune system and lung response. Patients with cystic fibrosis (CF) may be deficient in this vitamin. The aims of the study were to evaluate vitamin D levels and severity of lung disease in infants and preschoolers diagnosed with CF, and to compare them to a group of children without pancreatic insufficiency (PI). Methods: Patients with CF up to 4 years old were included, and compared to an agematched group of children without diagnosis of CF. CF group had medical records and High Resolution Thorax Computed Tomography (HRCCT) evaluated in order to verify the severity of lung disease. Information on demographic data, sun exposure habits, supplemental vitamin D therapy, and on the season at the time of vitamin D sampling were collected for both groups.Results: This study included 45 patients in the CF group and 102 in the non-CF group, with no differences in age (P = 0.327) between them. There was no association between vitamin D levels and markers of lung disease in the CF group. The non-CF group had lower daily sun exposure (P = 0.034), and lower supplementation than the CF group (P < 0.001). Supplementation and seasonality were the determinant variables for vitamin D levels, which were lower for non-supplemented children and for assessments during fall/winter. Conclusion:There was no association between lung disease severity and vitamin D levels in CF group. Supplementation and seasonality were associated to higher vitamin levels. K E Y W O R D Scystic fibrosis, infants and preschoolers, lung disease, neonatal screening, vitamin D

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“…Ultraviolet (UV) radiation available in sunlight is essential for the biochemical production of vitamin D naturally . However, overexposure to UV radiation causes skin cancer, melanoma and other damaging effects such as erythema (sunburn), suppression of immune system, photo‐aging, reactive oxygen species (ROS) generation and photodermatoses.…”

Section: Introductionmentioning

confidence: 99%

Tunable, Hybrid 1D ZnO Nanostructures Obtained by Using Bio‐renewable Ferulic Acid as Support and its Applications

et al. 2018

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Inorganic oxides such as titanium dioxide (TiO2) and zinc oxide (ZnO) are desired as ultraviolet (UV) filters. Such UV‐filters derived from naturally occurring oxides are promising components for formulating personal care products sustainably. However, UV‐filters based on inorganic oxides pose challenges to formulators and users in terms of strong adherence to skin and high photocatalytic activity. As a means to influence the morphology of such functional oxides, a simple one‐dimensional (1D) ZnO nanorod was synthesized via solvothermal technique assisted by the seed‐growth method. Thus bio‐renewable ferulic acid (FA) was used as a capping and structure‐directing agent to obtain tunable nanostructures such as spheres, sheets, and rods. SEM and TEM analyses revealed the self‐assembled elongated morphology with increased aspect ratio. Based on these as well as other analyses the growth mechanism of zinc oxide functionalized ferulic acid (ZnO@FA) was investigated. ZnO@FA also exhibited broad absorption in the UV−B and A regions, unique antioxidant behavior along with a highly suppressed photocatalytic activity. The ZnO@FA are sustainable, functional materials. These materials are potentially useful in areas such as cosmetics, functional coatings, sensors and solar cells.

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UVR: sun, lamps, pigmentation and vitamin D

Cited by 37 publications

References 66 publications

Influence of Undoped‐AlGaN Final Barrier of MQWs on the Performance of Lateral‐Type UVB LEDs

Influence of Undoped‐AlGaN Final Barrier of MQWs on the Performance of Lateral‐Type UVB LEDs

Lung disease and vitamin D levels in cystic fibrosis infants and preschoolers

Tunable, Hybrid 1D ZnO Nanostructures Obtained by Using Bio‐renewable Ferulic Acid as Support and its Applications

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