Effects Of Ultraviolet Radiation Research Articles

Effect of gamma and ultraviolet irradiation on the optical properties of copper oxide nanostructured thin films by chemical spray pyrolysis

Nanostructured copper oxide thin films were grown by the chemical spray pyrolysis (CSP) technique. Utilizing a homemade spray pyrolysis method, thin films are created. This work investigates the role of gamma ray and ultraviolet ray irradiation on the optical properties of copper oxide thin films(CuO) prepared. In this framework, used different substrate temperatures 300 °C, 350 °C, and 400 °C for the layers were grown on glass for the prepared CuO thin films. UV–visible spectrometer, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction patterns(XRD) measurements were all used to characterize the samples. The UV–visible spectroscopy showed a decrease in the absorbance and the optical band gap of CuO thin films with the increase in the higher substrate temperatures before irradiation. Additionally, surface plasmon resonance peaks (λSPR) were observed at 329 nm. FE-SEM images revealed spherical-like shapes with an average diameter range of 48 nm,56 nm and 62 nm for 300 °C, 350 °C, and 400 °C, respectively. An analysis of X-rays revealed that CuO thin films contained the crystallographic planes of a monoclinic and an orthorhombic crystal system. Also, when samples were exposed to gamma and UVC radiation, the absorbance intensity of CuO thin films increased, but the optical band gap decreased.

Investigation of the Influence of UV Radiation on Compositions of Polylactide with Graphite Nanoplates

Composites of polyether polylactide (PLA) synthesized from natural raw materials with graphite nanoplates (GNP), which represent a new type of composite materials based on biodegradable polymers, were obtained by solid-phase method under the action of shear deformations. The porosity of composites was evaluated and their electrical and mechanical properties were studied. The effect of UV radiation on the molecular weight and molecular weight distribution of PLA in PLA-GNP composites of different compositions was investigated using the method of excision chromatography (EC), and the effect of the GNP nanofiller content on the change of their mechanical characteristics in the process of radiation was shown.

Dynamics of Degradation of Polylactide-Natural Rubber Compositions under the Influence of UV Irradiation

The effect of ultraviolet radiation of various wavelengths (254 nm and 365 nm) on compositions based on polylactide with the addition of natural rubber was studied. It was found that the effect of the wavelength of 254 nm on the studied samples is much more active than 365 nm, which is characterized by a decrease in the melting temperature and the degree of crystallinity of polylactide in the compositions, as well as a deterioration in physical and mechanical properties. The IR spectroscopy method confirms the photodegradation process by changing the intensities of structurally sensitive polylactide and natural rubber bands.

Preparation and Performance Study of Ultraviolet-Responsive Self-Healing Epoxy Asphalt.

In this study, a self-healing epoxy asphalt material was developed by incorporating coumarin groups. This material achieved microcrack self-repair under UV irradiation at 50 °C. Fluorescence microscopy observations and mechanical performance tests demonstrated significant advantages in crack filling and mechanical property recovery after repair, with the fracture toughness of the repaired epoxy asphalt reaching 69% of that in its original state. Furthermore, the synergistic effect of temperature and UV irradiation in the self-healing process enhanced the material's durability and service life. This research offers new insights and methods for developing more durable and long-lasting self-healing asphalt materials, showcasing the great potential of smart materials in infrastructure applications.

Ambient ultraviolet radiation as a cardioprotective factor: A global and regional analysis.

Ambient ultraviolet radiation (UVR) has been found to have a greater cardioprotective effect than previously believed. This study aimed to quantitatively measure the role of UVR in protecting against the progression of cardiovascular disease (CVD) in general on a global and regional scale. Population-level data on UVR, CVD incidence, aging, economic affluence, CVD genetic background (indexed with the Biological State Index, Ibs), obesity prevalence, and urbanization were collected and analysed. The correlation between UVR and CVD was examined using bivariate correlations, partial correlation, and stepwise multiple linear regression. Countries were grouped to investigate regional correlations between UVR and CVD, and Fisher's r-to-z transformation was used to compare correlation coefficients. UVR showed a significant inverse correlation with CVD incidence rates in bivariate correlation analyses globally (r = - 0.775 and r = - 0.760, p < 0.001), as well as within high-income (r = -0.704, p < 0.001) and low- and middle-income countries (LMIC) (r = -0.851, p < 0.001). These correlations remained significant even after controlling for confounding variables (r = -0.689 to -0.812, p < 0.001). In stepwise regression models, UVR was found to be the most significant predictor of CVD incidence. The inverse correlation between UVR and CVD was stronger in LMICs compared to high-income countries (z = -1.96, p < 0.050). Low ambient UVR may be a significant risk factor for the progression of CVD worldwide. The protective effect of UVR appears to be stronger in LMICs than in high-income countries, suggesting a greater impact of UVR on CVD prevention in these regions. These findings emphasize the need for further research into the mechanisms underlying the cardioprotective effects of UVR and the development of public health strategies to mitigate CVD risk associated with low UVR exposure.

Sol–gel prepared ZnO: UV irradiation effect on structure and surface properties

The effect of UV irradiation on sol–gel prepared ZnO films subjected to mild thermal annealing was investigated, with special attention to their structural and surface properties. Sol–gel processes, including a high-temperature annealing stage, have been adapted to the requirements of flexible electronics for in situ synthesis of semiconductor ZnO films on polymer substrates at lower temperatures due to UV irradiation. Application of UV radiation with emission peaks at 185 and 254 nm to films annealed at 180 °C made it possible to obtain ZnO films with Zn/O ratios of ca. 1, which cannot be achieved by heat treatment alone.

Ultraviolet irradiation enhances the nitration of allergens

Ultraviolet (UV) light is widely used for disinfection in indoor environments. Some wavelengths of UV light can produce high concentration of O3. UV irradiation combined with O3 may have great potential for nitration of allergens in the presence of NO2 in the air. In this study, the effects of UV irradiation on the nitration of three major indoor allergens including group Ⅰ allergens of house dust mite (Der p 1 and Der f 1) and group Ⅰ allergen of dog (Can f 1) in the presence of NO2 and O3 were investigated by analysis of the protein quantity, tyrosine, peptides, and nitration degree. The results showed that UV irradiation induced a significant increase in the quantity of 3-nitrotyrosine in the allergens from 0.4 ± 0.4 ng to 4.0 ± 0.8 ng. After 12 h of UV-O3 co-exposure, the total nitration degrees of the three allergens ranged from 0.1% to 0.5%, which were significantly higher than those after only O3 exposure (p < 0.05). The analysis of peptides revealed that the nitration of tyrosine was site-specific. The tyrosine Y231, which was adjacent to aspartic acid, posed the highest nitration degree of 41.1 ± 24.0% in Der p 1. The nitration degree of tyrosine Y162 was the highest (1.7 ± 0.1%) in Der f 1. Overall, this study demonstrated that UV irradiation enhanced the O3-related nitration of allergens in the air, which provides an experimental basis for the impact of daily disinfection behavior on allergens.

Effect of combination of ultraviolet radiation and biocide on fungal-induced corrosion of high-strength 7075 aluminum alloy

The effect of ultraviolet (UV) radiation and biocide benzalkonium chloride (BKC) on fungal-induced corrosion of AA7075 induced by Aspergillus terreus (A. terreus) was deeply studied using analysis of biological activity, surface analysis, and electrochemical measurements. Results demonstrated that the planktonic and sessile spore concentrations decline by more than two orders of magnitude when UV radiation and BKC are combinedly used compared with the control. UV radiation can inhibit the biological activity of A. terreus and influence the stability of passive film of AA7075. Except for direct disinfection, the physical adsorption of BKC on the specimen can effectively inhibit the attachment of A. terreus. The combination of UV radiation and BKC can much more effectively inhibit the corrosion of AA, especially pitting corrosion, due to their synergistic effect. The combined application of UV radiation and BKC can be a good method to effectively inhibit fungal-induced corrosion.

Effects of preharvest UV irradiation combined with postharvest storage temperature and low light irradiation during storage on the functional compounds of komatsuna (Brassica rapa var. perviridis)

Effects of preharvest UV irradiation combined with postharvest storage temperature and low light irradiation during storage on the functional compounds of komatsuna (<i>Brassica rapa</i> var. <i>perviridis</i>)

Photoprotective Melanin is Maintained Within Keratinocytes in Storage Lysosomes

In the skin, melanin is synthesized by melanocytes within melanosomes, and transferred to keratinocytes. After being phagocytosed by keratinocytes, melanin polarizes to supranuclear caps that protect against the genotoxic effects of ultraviolet radiation. We provide evidence that melanin-containing phagosomes undergo a canonical maturation process, with the sequential acquisition of early and late endosomal markers. Subsequently, these phagosomes fuse with active lysosomes, leading to the formation of a melanin-containing phagolysosome that we named melanokerasome. Melanokerasomes achieve juxtanuclear positioning via lysosomal trafficking regulators Rab7 and RILP. Mature melanokerasomes exhibit lysosomal markers, elude connections with the endo/phagocytic pathway, are weakly degradative, retain undigested cargo and are likely tethered to the nuclear membrane. We propose that they represent a lysosomal-derived storage compartment that has exited the lysosome cycle, akin to the formation of lipofuscin in aged cells and dysfunctional lysosomes in lysosomal storage and age-related diseases. This storage lysosome allows melanin to persist for long periods, where it can exert its photoprotective effect efficiently.

Unveiling the oxidative stability, phytochemical richness, and nutritional integrity of cold-pressed Linum usitatissimum oil under UV exposure

This study examines the effect of UV irradiation on the oxidation stability of Linum usitatissimum oil, presenting possible changes in the phytochemical profile due to photo-oxidation. GC–MS analysis of the oils identified 11 fatty acid compounds with a high percentage of unsaturated fatty acids, the most important of which is α-linolenic acid (ALA), known as omega-3 (48.88 %), also significant profiles of phytosterol and tcocopherol isomers rich in β-Sitosterol and γ-tocopherols respectively. As well as physicochemical properties such as free fatty acids (FFA %), peroxide value (PV) and iodine value (IV), and nutritional indexes that determine the significant changes observed during the oxidation process, the most important of which is the progressive increase in acidity, peroxide, conjugated dienes and trienes and degrees of unsaturation over 8 h of UV exposure. High levels of carotenoids and phenolic compounds (TPC) protect and enhance oil quality in the face of irradiation, so a significantly small difference is observed between irradiated and non-irradiated oil during photo-oxidation.

Preliminary Study of the Characterization of the Viable but Noncultivable State of Yersinia enterocolitica Induced by Chloride and UV Irradiation.

The viable but non-culturable (VBNC) state is a survival strategy for many foodborne pathogens under adverse conditions. Yersinia enterocolitica (Y. enterocolitica) as a kind of primary foodborne pathogen, and it is crucial to investigate its survival strategies and potential risks in the food chain. In this study, the effectiveness of ultraviolet (UV) irradiation and chlorine treatment in disinfecting the foodborne pathogen Y. enterocolitica was investigated. The results indicated that both UV irradiation and chlorine treatment can induce the VBNC state in Y. enterocolitica. The bacteria completely lost culturability after being treated with 25 mg/L of NaClO for 30 min and a UV dose of 100 mJ/cm². The number of culturable and viable cells were detected using plate counting and a combination of fluorescein and propidium iodide (live/dead cells). Further research found that these VBNC cells exhibited reduced intracellular Adenosine Triphosphate (ATP) levels, and increased levels of reactive oxygen species (ROS) compared to non-induced cells. Morphologically, the cells changed from a rod shape to a shorter, coccobacillary shape with small vacuoles forming at the edges, indicating structural changes. Both condition-induced VBNC-state cells were able to resuscitate in tryptic soy broth (TSB) medium supplemented with Tween 80, sodium pyruvate, and glucose. These findings contribute to a better understanding of the survival mechanisms of Y. enterocolitica in the environment and are of significant importance for the development of effective disinfection strategies.

Effect of UV radiation on shear behaviour between geotextile and geomembrane interface

Effect of UV radiation on shear behaviour between geotextile and geomembrane interface

Effect of ultraviolet radiation c treatment on preservation of Naematelia aurantialba in modified atmosphere packaging

Naematelia aurantialba, known for its health benefits but perishable due to high water content, has a limited market life. This study explored extending its shelf life using ultraviolet C radiation within modified atmosphere packaging. Ultraviolet C, typically used for sterilizing produce, has untapped potential for preserving Naematelia aurantialba. Samples underwent ultraviolet C with various intensities, then were stored at 2 ± 1 °C in packaging bags with 4081 mL/m2·d·atm oxygen transmission rate, with quality checks every seven days until day 42. Samples treated with 0.19 kJ/m² ultraviolet C radiation within the MAP system significantly slowed color and texture changes in N. aurantialba, maintaining cell integrity. This treatment also reduced the loss of aroma substances and significantly increased the total phenolic and flavonoid content in the N. aurantialba. Simultaneously, these samples demonstrated tester preference, highlighting the treatment's effectiveness in enhancing freshness and marketability.

Effect of Ultraviolet Radiation from Welding Activities on Ocular Tissues of Albino Rats

Effect of Ultraviolet Radiation from Welding Activities on Ocular Tissues of Albino Rats

TiO2-catalyzed photodegradation of methylene blue in a helical FEP tubing reactor: modeling and optimization using response surface methodology

A novel photocatalytic reactor was developed to degrade methylene blue in water using titanium dioxide (TiO2) as a catalyst and fluorinated ethylene propylene (FEP) tubing as a transmitter for ultraviolet (UV) radiation. The reactor was operated by continuously flowing the solution through narrow tubes that were exposed to UV radiation. The efficiency of the reactor was evaluated by comparing it to a previous study that used quartz glass tubing. The study also investigated the effects of flow rate, initial concentration, pH, TiO2 dose and UV radiation without a catalyst on the degradation of methylene blue. The results showed that the FEP tubing was a more efficient UV transmitter than quartz glass. The efficiency of the reactor was also affected by the flow rate and pH of the solution. The highest degradation efficiency was achieved at a flow rate of 10 mL/min and a pH of 7.0. The use of TiO2 as a catalyst also significantly improved the degradation efficiency, with an almost doubling of the degradation rate when compared to the case without a catalyst. This study demonstrates the potential of the FEP tubing-based photocatalytic reactor for the degradation of methylene blue in water. The reactor is easy to operate and can be scaled up for industrial applications.

Would Rutin be a Feasible Strategy for Environmental-Friendly Photoprotective Samples? A Review from Stability to Skin Permeability and Efficacy in Sunscreen Systems

Rutin, a flavonoid found in various plants, has gained attention for its potential applications in the cosmetic industry due to its antioxidant, anti-inflammatory, and potential photoprotective properties. Our review explored the use of rutin (rutoside, 3-O-rutinoside-quercetin) in cosmetics/dermocosmetics, focusing on its physicochemical properties and stability, cutaneous permeability, and efficacy in sunscreen systems, involving in vitro tests and the current state of clinical trials. Rutin’s ability to scavenge free radicals, prevent peroxidation, and reduce vascular fragility makes this flavonoid a promising ingredient for photoprotection. Studies have shown that rutin can enhance the sun protection factor (SPF) of sunscreen formulations, especially when combined with organic UV filters. The encapsulation of rutin in nanostructures has also been investigated to improve its applicability. Overall, rutin shows potential as a safe and effective ingredient in cosmetics/dermocosmetics, offering protection against the harmful effects of UV radiation and oxidative stress on the skin, as well as being a feasible strategy for developing environmentally friendly multifunctional sunscreens.

Portable Voltammetry: A Rapid and Efficient Technique for Determining UV Filters in Cosmetics: A Comparative Study with HPLC-PDA and HPLC-MS/MS.

This study addresses the widespread use of UV filters (UVFs) in cosmetic and solar products due to the negative effects of UV radiation, particularly in relation to melanoma risk. While these filters offer protection, their extensive application raises concerns about their environmental and health impacts. Organic UVFs, in particular, have been associated with endocrine disruption in aquatic species and coral reef damage. To mitigate these concerns, regulatory limits have been imposed on certain UVFs. Current analytical techniques for UVF determination, such as HPLC-PDA and HPLC-MS/MS, offer high accuracy but are expensive and lack on-site monitoring capabilities. In response, this research aims to develop a rapid and cost-effective method, utilizing voltammetry for organic UVF quantification in complex matrices like sunscreens. Additionally, HPLC-PDA and HPLC-MS/MS are employed for electrochemical methods and device validation. This approach not only addresses the need for efficient UVF analysis but also provides a basis for regulatory compliance and environmental stewardship in the cosmetics industry.

Obtaining Melanin-Synthesizing Strains of Bacillus thuringiensis and their Use for Biological Preparations.

A pivotal objective in crop production and plant protection lies in developing environmentally friendly insecticidal preparations and biostimulants. We employed Bacillus thuringiensis strains with varied insecticidal spectra and engineered melanogenic mutants. We demonstrated a significant increase in insecticidal activity in the isolated mutants. Meanwhile, there was no observable impact of the enhanced synthesis of water-soluble melanin on the nature and abundance of spore and crystal formation. This heightened efficacy can be attributed to the photoprotective qualities of the synthesized pigment, shielding spores and crystals against the detrimental effects of UV radiation and insolation. We demonstrated the high biological activity of water-soluble bacterial melanin through in vivo experiments involving multiple plant species. Our findings indicate that bacterial melanin is a potent phytostimulant. This preparation accelerates and amplifies plant growth and development processes, leading to a substantial increase in crop yield by 20-40%. The simultaneous synthesis of two biologically active substance, melanin and insecticidal toxins, ensures an elevated level of effectiveness in utilizing melaninogenic strains.

Changes in quality attributes of coconut water treated with UV-radiation and nisin during cold storage: Kinetics modelling and shelf-life prediction

Exploring the innovative combination of UV radiation and nisin treatment for enhancing the shelf life and quality of coconut water (CW) offers promising avenues for sustainable beverage processing. This study investigated the effects of UV radiation, nisin, and their combined treatments on the physical and microbiological attributes of coconut water during 20 days of refrigerated storage. The study also aimed to develop mathematical models for tracking changes in coconut water's quality parameters during refrigerated storage and determining its shelf life by integrating quality and microbial metrics. The results revealed that the cold storage period has significant impacts on the physical and microbiological characteristics of coconut water. The combination of UV radiation and nisin resulted in microbiologically stable coconut water, with populations remaining below 106 CFU/mL, for up to 20 days of cold storage. Moreover, a decline in pH over time, particularly in UV and nisin-treated samples, indicated increased acidity by only 15%. Colour analysis showed shifts towards darker and redder hues, accompanied by increases in a*-values. Conversely, b*-values increased in most samples, except for pasteurized coconut water. Additionally, a consistent decrease in antioxidant activity, total phenolic compound, and total flavonoid content was observed in the samples treated with the combination of UV radiation and nisin during storage period, with averages of 50%, 18%, and 20%, respectively. The zero-order model accurately represented most coconut water's properties, exhibiting R2 value of ≥0.85, and the derived reaction rate constants used to predict shelf life. Integration of UV and nisin treatment significantly extended the projected shelf life of coconut water compared to control (untreated CW sample) and individual treatments except thermal treatment, with shelf-life extensions of up to 19.5 days, highlighting the potential of this combination to enhance coconut water's shelf life while maintaining its safety.