Solar Ultraviolet Rays Research Articles

Formulation cream from extract of red pidada leaves (Sonneratia caseolaris L.) as a sunscreen and analysis of active compounds with Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) method

Exposure to intense and prolonged solar ultraviolet rays can cause erythema, premature aging, and skin cancer. The prevention of ultraviolet rays can be done by using sunscreen. Red Pidada leaves (Sonneratia caseolaris L.) have sunscreen properties. The purpose of this study was to preformulate red Pidada leaves into sunscreen cream preparations with the best activity as a cosmetic product prototype. This research will be started with the preparation of the red Pidada leaf ethanol extract formulated into a cream preparation with the extract concentration of Formula 1 (8%), Formula 2 (15%), and Formula 3 (20%). Evaluation of cream preparations includes organoleptic test, pH test, homogeneity test, dispersion test, adhesion test, viscosity test, and sunscreen effectiveness test. Data analysis used the One Way ANOVA test. The results of the physical quality test of cream showed that Formula 1 (8%) and Formula 2 (15%) met the requirements of the organoleptic test, homogeneity test, and adhesion test but did not meet the pH test, viscosity test, and spread ability test. Formula 3 (20%) fulfils the organoleptic test requirements and adhesion test requirements but does not meet the homogeneity test, pH test, viscosity test, and spread ability test. The sunscreen effectiveness test in formula 1 has the lowest Sun Protection Factor (SPF) value of 1.5 (without protection), formula 2 has an SPF value of 2.9 (minimum protection), and formula 3 has the highest SPF value of 7.4 (protection extra). Analysis of bioactive compounds in red Pidada ethanol extracts using LC-HRMS. There were 6 active compounds. Diisobutylphtalat, luteolin, apigethrin, vitexin, choline and bethain. Formula 3 performs better as a sunscreen than Formulas 1 and 2.

EVALUATION OF THE EFFICIENCY OF EGGSHELL ASH AS PHOTOCATALYST FOR DECOLOURISATION OF AZO DYE USING SOLAR UTRA-VIOLET RADIATION

Water pollution is one of the environmental challenges to be surmounted to avoid global public health hazard. Due to the complex chemical structure, azo dyes in industrial effluent have a long shelf life and are toxic to aquatic creatures even at low quantities. In this study, the decolourisation of azo dye, methylene blue (MB) using locally sourced photocatalyst, eggshell ash (ESA) under solar ultra-violet (UV) radiation was investigated. In order to test the photo-activities of ESA, a similar study was performed without sunlight. ESA was characterised using Fourier transform infrared (FTIR) spectroscopy. Maximum decolourisation efficiencies (96% with sunlight and 77% without sunlight) were recorded at contact time of 120 minutes and 1.5 g/dm3 of catalyst. The data obtained were fitted into kinetics models and adsorption isotherms. According to the findings, pseudo-second order kinetics model best described the process with rate constant of 0.1529 g/mg.min and regression value, R2 of 0.9934. Intra-particle diffusion model showed that the uptake of MB was more of film diffusion than the intra-particle diffusion. The adsorption isotherm fitted better into Langmuir isotherm with adsorption capacity of 0.0213 dm3/mg and R2 of 0.9957, while the Temkin isotherm indicates that the process was a physical adsorption as the heat of sorption value (0.0015 Kcal./mol.) was less than 1.0 kcal/mol. Generally, the study revealed that ESA was a suitable photocatalyst for the decolourisation of azo dyes under solar UV rays.

Expired EBT3 Films' Sensitivity for the Measurement of X-ray and UV Radiation: An Optical Analysis.

The aim of this study is to compare the optical responses of external beam therapy 3 (EBT3) films exposed to X-rays and solar ultraviolet rays (SUV-rays), as a dose control technique in the clinical sector for various radiation types, energies, and absorbed doses up to 4 Gy. In this study, EBT3 films with three different expiry dates were prepared and cut into pieces of size 2 by 2 cm2. The first group was exposed to 90 kVp X-rays, while the second group was exposed to the SUV-rays at noon. The analysis was performed using a visible Jaz spectrometer and an EPSON Perfection V370 Photo scanner to obtain the absorbance, the net reflective optical density (ROD) and the red-green-blue (RGB) values of the samples. The results have shown that spectroscopic measurements of the exposed expired EBT3 films with these radiation sources are able to produce primary peaks and secondary peaks at λ = 641.74 nm and λ = 585.98 nm for X-rays, and at λ = 637.93 nm and λ = 584.45 nm for SUV-rays, respectively. According to these findings, compared to 2021 films that expired shortly before the trial start date; 2018 films responded better to the absorbed dose than 2016 films when exposed to both X-ray and SUV-rays. In terms of energy dependence, the expired EBT3 2018 had the largest net ROD value. Using L*a*b* indices extracted from the RGB data, and despite that EBT3 films have expiry dates according to the manufacturer; all the films exhibited a substantial colour change, indicating that these films are still usable for clinical and research purposes.

Occupational Exposure to Solar Radiation at Different Latitudes and Pterygium: A Systematic Review of the Last 10 Years of Scientific Literature.

Pterygium is a chronic eye disease: among its recognized risk factors there is long-term exposure to ultraviolet (UV) radiation. The Sun is the main source of UV exposure: according to the World Health Organization, the Population Attributable Fraction of pterygium due to solar radiation (SR) is 42–74%. Outdoor work can deeply influence the eye exposure to solar UV rays, but, despite this, pterygium is currently not adequately considered as a possible occupational disease in this working category, at least in Europe. For this reason, we performed a systematic review of the scientific literature published in the last ten years (2008–2017) considering the role of outdoor work as a risk factor for pterygium, in order to give new support for the prevention of this UV related disease in workers. We identified 29 relevant papers. Our results show that pterygium prevalence highly increased with latitude and mean annual UV index, and outdoor work is one of the most relevant risk factors, as well as age and male sex, both in high risk and in moderate risk World areas considering the environmental UV levels. Accordingly, pterygium occurring in outdoor workers should be considered an occupational disease. Moreover, our findings clearly support the need of further research on more effective prevention of the occupational risk related to long-term solar radiation exposure of the eye.

Extraction of juglone from Pterocarya fraxinifolia leaves for dyeing, anti‐fungal finishing, and solar UV protection of wool

In many countries, the search for new sources of natural colourants has recently been intense. This paper deals with the extraction procedure, dyeing behaviour, antifungal activity, and ultraviolet protection of Pterocarya fraxinifolia as a new natural source of dyes. Juglone was found as the main extracted compound after characterisation by ultraviolet‐visible spectrophotometry and Fourier transform infrared spectroscopy. Mordanting and subsequent dyeing of wool with extracted juglone were then performed to study the dyeability and antifungal activities. Three metal salts, aluminium sulfate, copper sulfate, and iron sulfate, were used as chelating materials. The colorimetric properties of samples were evaluated using a reflectance spectrophotometer. Furthermore, the washing and light fastness properties were tested according to ISO 105‐CO3:1989 and ISO 105‐B01:2014. Interestingly, we found P. fraxinifolia to be a source of strong antifungal compounds against microorganisms. Extracted juglone also exhibited strong protection activity against solar ultraviolet rays.

Cancer: UV Protection from Plants

Excessive exposure to the sun’s ultraviolet (UV) rays can exact a heavy toll on skin health, resulting in an increased risk of skin cancers as well as other telltale signs of photoaging. In the United States alone, more than 1 million cases of skin cancer are diagnosed each year, accounting for almost 40% of all new cancer cases, according to the National Cancer Institute. Thus, the search continues for better ways to prevent the deleterious effects of too much sun. One approach, photochemoprotection, uses pharmacologically active plant-derived compounds, administered either orally or topically, to prevent carcinogenic sun damage. A compelling feature of photochemoprevention is its focus on specific aspects of skin cancer biology. “Phytochemicals can be employed to intervene at the initiation, promotion, or progression stages of the multistage cancer process,” says Farrukh Afaq, a dermatology researcher at the University of Wisconsin–Madison. “Since multiple pathways are involved in [the] photocarcinogenic response, a mixture of several phytochemicals working through different cell signaling pathways or other mechanisms could be an effective strategy.” A review by Afaq and colleagues in the March–April 2008 issue of Photochemistry and Photobiology summarizes the photochemoprotection strategies that show the most promise, among them green tea polyphenols (GTPs), grape seed proanthocyanidins (GSPs), resveratrol from grapes, silymarin from milk thistle, curcumin from turmeric, beta-carotene, and extracts of pomegranate fruit. Afaq notes that many of these compounds have been shown to target the NF-κB, AP-1, MAPK, and PI3K/AKT pathways, all of which are involved in photocarcinogenesis and the progression of skin cancers. “Along with antioxidant, anti-inflammatory, and DNA repair effects, a number of these agents also have immune-modulating properties,” says Santosh Katiyar, a dermatology professor at the University of Alabama at Birmingham who was not a part of the study. “This is important, since chronic exposure to solar UV radiation suppresses immune reactions, and since such suppression has been implicated in the development of skin cancer.” Under the guidance of UW–Madison cancer researcher Hasan Mukhtar, the group has launched a program to define the cancer-curbing potential of phytochemicals and establish their mechanisms of action. “These phytochemicals essentially function in two ways,” says Mukhtar. “The first way is to have the ability to scavenge highly damaging and reactive free radicals that are formed when the skin is exposed to solar UV rays. The second is through their effects on signal transduction molecules that are induced in the skin in response to UV rays.” Most of the evidence to date has come from laboratory data, mainly for reasons of cost and practicality. “Evidence from human trials continues to be quite limited, in large part because of the long period of photocarcinogenesis in humans,” says Stephen Hsu, a molecular medicine professor at the Medical College of Georgia in Augusta. “These trials may take ten or more years in comparison to rodent studies, which can be completed in a matter of months.” In addition, he says, the bioavailability of GTPs and GSPs in their original forms is very low, whether used orally or topically, so high doses had to be used in the animal studies to achieve the desired efficacy. The Wisconsin group notes in their review that combinations of antioxidant phytochemicals may therefore be necessary to achieve the desired level of photochemoprevention. “Some skin care products already contain phytochemicals,” says Afaq. “In conjunction with other sun-safe measures, use of these products may be an effective approach for reducing [UV-mediated] photodamage, inflammatory responses, photoaging, and skin cancer in humans.” Afaq and Mukhtar assert that individuals can modify their dietary habits in combination with targeted use of skin care products and botanical antioxidants, perhaps eventually enabling people to enjoy the sun’s health benefits [see “Benefits of Sunlight: A Bright Spot for Human Health,” EHP 116:A160–167 (2008)] without the dermatologic consequences.

Effectiveness of Eyeglasses for Protection Against Ultraviolet Rays

Purpose: The relationship between eyeglass size and protection of the eye surface from the effects of solar ultraviolet (UV) rays was investigated. Methods: Solar UV rays irradiating the eye surface were measured on a mannequin which modeled the standard facial bone structure of a Japanese female. UV sensor chips (photo-sensitivity: 260–400 nm) were attached to the ocular surface of the lid fissure. UV measurement was done from 12:00 to 15:00 on a sunny day in March. UV intensity was measured under the following conditions: (1) with or without eyeglasses, (2) wearing sunglasses with side protectors, and (3) wearing a cap with a 7 cm brim. Eyeglasses of four frame sizes (width: 48–57 mm) were put on the mannequin. All lenses were made of plastic and coated so as to be impervious to rays shorter than 400 nm. The refractive power was 0 diopters. At the same time, UV irradiation intensity from all directions (excluding from the earth direction) was measured using a polyhedron type UV sensor with 25 sensor chips. Results: Except for eyeglasses with the smallest frame size, eyeglasses effectively reduced UV exposure to sunlight from the upper front direction. However, protection against rays from the upper temporal direction was extremely poor. Sunlight from the upper back was reflected by the posterior surface of the eyeglasses and reached the eye surface. Conclusion: The efficacy of eyeglasses against UV depends on their size. The shape of the eyeglasses and reflection from the posterior lens surface are also of great importance. Small eyeglasses and reflection from the posterior lens surface are also of great importance. Small eyeglasses do not offer ideal UV protection for the Japanese face shape. (J Jpn Ophthalmol Soc 103:379–385, 1999)

Geographical distribution of cutaneous melanoma in Queensland

Queensland has the highest incidence of cutaneous melanoma in the world, and the reported incidence has more than doubled in the last 15 years. The general geographical distribution of melanoma patients correlates negatively with latitude on a world scale. This suggests that exposure to solar ultraviolet rays is aetiologically important. The geographical distribution of melanoma patients in Queensland was examined by reviewing the residential addresses of all incident cases in a 12-month period from July 1, 1979, and no association with latitude was found. Rather there was a significantly increased incidence of melanoma in coastal, compared to inland, regions. When the distribution of doses of erythemal solar ultraviolet radiation in Queensland is examined, taking into account the effects of cloud cover, surface reflectance, and human behaviour, the observed regional differences in incidence may yet be explained by the variation in actual exposure to ultraviolet radiation received by the population.

Seasonal changes in human plasma levels of 25-hydroxyvitamin D.

THE relative importance of the two alternative sources of vitamin D, endogenous skin synthesis by the action of solar ultraviolet rays and dietary ingestion, is uncertain in Britain. In the past, classical rickets was common in springtime but rare in autumn1,2, suggesting that summer sunshine was an important source of vitamin D. Seasonal variation in plasma antirachitic activity has been detected in more southerly latitudes in the United States, using bioassay techniques3, but data from Britain are scanty and some workers have considered the effects of sunshine to be minimal in this climate4. Possible age or sex differences in vitamin D nutritional status are also unknown.

High Accuracy Attitude Control for Pointing to the Sun

Many observations of solar ultraviolet rays in terms of rockets have been made. The accuracy of pointing of a rocket towards the sun is now within one arc-min and spectrum analyses on the whole surface or the fringe of the sun were made with this pointing accuracy.Astronomers, however, wish to study particular small parts of the sun. For that purpose, accuracy of attitude control of the rocket has to be within one arc-sec about pitch, yaw and roll axis, respectively.Such high accuracy attitude control system planned was outlined and the digital computer simulation was made. The system is assumed to consist of three parts: (1) the coarse control system in terms of gas jets (2) the fine control system in terms of reaction wheels (3/ the sun-follower, (see Fig. 1)First, initially spinning nosecone is controlled to despin and to suppress precession. Secondly, the reaction wheels control the attitude of nosecone within the error of a few arc-sec. Finally the sun-follower keeps the image of the sun within the error of one arc-sec.In this paper, responses of both the coarse and the fine control system are discussed based on the digital computer simulation.

太陽紫外線量に就て(第6報)

太陽紫外線量に就て(第6報)

5) 教室内の太陽紫外線照射分布に就て

5) 教室内の太陽紫外線照射分布に就て

大陽紫外線量に就て(第四報)

大陽紫外線量に就て(第四報)

太陽紫外線量に就て(第五報)

太陽紫外線量に就て(第五報)