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UV exposure is a common method of disinfection and sterilization. In the present study, the parallel beam test was performed to collect fluids containing infectious viruses using a parallel beam apparatus after UV254 irradiation (0, 0.5, 1, 3, 5, 7, 10, or 20 mJ/cm2). The air sterilization test was performed by irradiating the air in the ducts with UV254 light (0, 1, 2, 3, 4, or 6 mJ/cm2) to collect airborne particles containing viruses through the air sterilization equipment. Furthermore, viral inactivation was assessed based on cytopathic effect (CPE) detection and immunofluorescent assays (IFA). Both the CPE and immunofluorescence signal intensity decreased as the UV254 dose increased. The UV254 doses required to inactivate ASFV (107.75 copies/mL), PRRSV (106.29 copies/mL), and PEDV (107.71 copies/mL) in the water were 3, 1, and 1 mJ/cm2, respectively. The UV254 dose required to inactivate ASFV (104.06 copies/mL), PRRSV (103.06 copies/mL), and PEDV (104.68 copies/mL) in the air was 1 mJ/cm2. This study provides data required for biosecurity prevention and control in swine farms. [ABSTRACT FROM AUTHOR]

Background: The pharmaceutical industry is faced with the problem of how to design and conduct tests to assess photostability during drug use and storage. In this study, the aim was to analyze the changes in total hemispherical reflectance (THR) and homogeneity in two preparations of tablets with clindamycin or tablets with phenoxymethylpenicillin stored under UV radiation. Methods: The analysis was performed for coated tablets with two types of antibiotics in and out of the direct package (i.e., non-blister and blister). The condition of UV radiation was maintained over 7 days in a Solarbox 1500 chamber. THR values were assessed after 3 and 7 days using a SOC-410 reflectometer. Hyperspectral evaluation was carried out with Specim IQ hyperspectral camera every 3 nm from 400 nm to 1030 nm. Results: THR values for both blister and non-blister tablets with clindamycin decreased significantly for the ranges 400–540 nm, 480–600 nm, 590–720 nm, and 700–1100 nm on day 3 of UV exposure. For non-blister clindamycin tablets, THR increased slightly on day 7 of the experiment compared to day 3, while THR continued to decrease for blister tablets. THR values for non-blister phenoxymethylpenicillin tablets decreased slightly on day 3 of UV exposure for the ranges 400–540 nm, 480–600 nm, 590–720 nm, 700–1100 nm, and 1000–1700 nm, and then on day 7 of UV exposure THR values increased to near baseline. In addition, non-blister clindamycin tablets showed a tendency to increase in a difference between max–min reflectance in the total spectral range as well as in visible and infrared light (p < 0.001 each). Similarly, day 7 blister tablets with clindamycin had a significantly higher max–min reflectance difference compared to day 3 blister tablets but only in the range of visible light (p = 0.034). Thus, the lowest homogeneity was demonstrated for 7 day tablets. On the contrary, the lowest homogeneity was observed for phenoxymethylpenicillin tablets on day 0 of experiment. Conclusions: UV radiation affects the total hemispherical reflectance values for clindamycin and phenoxymethylpenicillin tablets, but to a different extent and within a different spectral range for each type of tablet. The homogeneity of the tablets may also change over time with UV exposure. [ABSTRACT FROM AUTHOR]

Occupational exposures comprise of a broad range of factors in constant and direct contact with the ocular surface. Cataract, a leading cause of visual impairment globally, has been associated with various occupational exposures. This review critically examines existing literature on the relationship between occupational exposures and cataract development. We aim to synthesize findings from studies exploring the impact of occupational factors such as ultraviolet (UV) radiation, ionizing radiation, welding fumes, polyaromatic hydrocarbons, tobacco dust, and other elements on the prevalence and incidence of cataract among exposed populations. In our review, certain exposures, such as UV radiation, demonstrated strong evidence regarding their association with cataract development, while others presented suggestive evidence. Hence, further studies are needed to better understand exposures of greatest concern, which can subsequently inform regulations pertaining to occupational exposures in work environments. [ABSTRACT FROM AUTHOR]

This study investigates the impact of zinc oxide nanoparticles on epoxy resin systems and the ultraviolet (UV) aging resistance of modified epoxy resin composites using molecular dynamics (MD) simulations and experimental methods. Initially, various epoxy resin cross‐linking models are established through MD simulations to understand the influence of different nano ZnO contents on resin modification, further validated by experiments. Subsequently, the UV radiation resistance of nano ZnO–epoxy resin composites is assessed by subjecting them to high‐intensity UV radiation equivalent to 3 years of natural environmental conditions, analyzing changes in tensile properties, impact performance, hardness, and glass transition temperature of epoxy resin before and after UV radiation exposure. The findings suggest that the addition of nano zinc oxide reduces the impact of UV radiation on epoxy resin, with optimal UV radiation resistance observed at a nano zinc oxide mass fraction of 0.3 wt%. [ABSTRACT FROM AUTHOR]

In the papermaking industry, cellulose fibers often undergo a bleaching process which affects the surface of the fibers, or their overall morphology. The surface of the produced paper, which is most often used as a printing substrate, depends on the production method, the arrangement of the cellulose fibers, and the quantity and fineness of the filler. The micro-irregularities caused by the uneven distribution of fibers and surface particles of the filler make the paper's surface rough and affect the print quality and its stability when exposed to light from the moment of production to use. The unbleached cellulose fibers in the printing substrate contain natural pigments, lignin and hemicellulose that absorb UV radiation, as opposed to bleached fibers, which have higher whiteness and lightfastness. Therefore, the influence of UV radiation on the surface roughness of prints made on papers with natural unbleached and bleached hemp fibers was analyzed. This research confirmed that papers formed from unbleached fibers have rougher surface and that printed graphic products from bleached fibers have higher stability to UV radiation than those from natural, unbleached hemp fibers after 96 h of treatment in the Suntest chamber. [ABSTRACT FROM AUTHOR]

Prolonged sun exposure disrupts the skin's structural, mechanical, and functional properties, accelerating aging and contributing to skin disorders. To counteract these effects, we developed a formulation containing potent antioxidant, anti-inflammatory, moisturizing, and reparative ingredients to protect and repair sun-damaged skin. The efficacy of the formulation was evaluated through in vitro, ex vivo, and in vivo studies. Results demonstrated that the formulation reduced oxidative stress and suppressed the production of pro-inflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8), as well as lactate dehydrogenase (LDH) secretion, in a photodamaged skin model, nearly reaching levels observed in undamaged skin. It also restored collagen levels, improving structural integrity. In vivo, no adverse reactions were observed when used for 28 or 56 days. The formulation improved skin hydration by up to 46%, reduced transepidermal water loss by 20%, increased luminosity by 70%, and reduced hyperpigmented spots by 14%. It also enhanced skin firmness and elasticity by 30% and reduced wrinkle volume and density by up to 53% and 19%, respectively. These findings demonstrate that the formulation's active ingredients effectively target the pathways altered by UV exposure, offering considerable potential for preventing and reversing sun-induced skin damage while improving both the appearance and functionality of the skin. [ABSTRACT FROM AUTHOR]

In this study, the effect of silica nanoparticles (SNPs) and UV radiation on the removal of zearalenone (ZEN) from sunflower oil was investigated. Pure sunflower oil samples showed no contamination with ZEN. The optimal conditions for ZEN removal using SNPs were determined to be a contact time of 240 minutes, an initial ZEN concentration of 25 μg/L, and 4 mg of SNPs. The kinetic data conformed to the Freundlich model and pseudo-second-order model. The results showed that SNPs have a high adsorption capacity and act as an effective adsorbent for removing ZEN from sunflower oil. The effect of SNPs in reducing ZEN was significantly more effective than UV radiation. The probable adsorption mechanism includes the chemical bonding of ZEN functional groups with silica groups and the high porosity of SNPs. Due to the low cost and non- toxic nature, the use of SNPs was introduced as an effective method for ZEN removal from food products. This method can be utilized as an efficient approach for ZEN removal in natural samples like edible oil. [ABSTRACT FROM AUTHOR]

This study investigates the potential of hydrolyzed bacterial cellulose (hBC) for UV radiation protection. BC membranes are produced under static conditions by Komagataeibacter sucrofermentans, purified, mechanically shredded, and hydrolyzed. As a result, hBC exhibits colloidal properties at various concentrations (0.34 – 11 mg ml−1). With a water-holding capacity of 89.1% ± 0.341, hBC forms a 3.65 μm thick transparent film with an approximate density of 7 μg per mm2. In Scanning Electron Microscopy (SEM) analysis, the lengths of filamentous BC particles were between 50 and 300 nm, while the lengths of rod-like nanocrystalline cellulose were between 400 and 1500 µm. According to dynamic light scattering (DLS) result, 88% of the particles were approximately 1 µm long. The zeta potential was −25.13 ± 0.65 mV, hBC showed thixotropic behaviour, and its crystallinity was 92. hBC and its films exhibited barrier properties to UV radiation (190–400 nm). The highest UV absorbance (almost 100%) for all UV regions (UV-A, UV-B and UV-C) of hBC in colloidal form is at a concentration of 11 mg ml−1. At most, the UV transmittance of all UV regions of the hBC films was 16%. Sun protective factor (SPF) values of colloidal and film forms of the hBC at a concentration of 11 mg ml−1 and 212 µg/mm2 were 29 and 12, respectively. hBC was not cytotoxic on mouse fibroblast L929 and human keratinocyte (HaCaT) cells. In conclusion, hBC can be an alternative UV radiation protector and thickening agent. This study represents the first report on the UV barrier property of hBC for aqueous formulations. [ABSTRACT FROM AUTHOR]

Cutaneous melanoma accounts for the majority of skin cancer-related deaths, and its incidence increases each year. The growing number of melanoma cases, especially in advanced stages, poses a significant socio-medical challenge throughout the world. Extensive research on melanoma pathogenesis identifies UV radiation as the most important factor in melanocytic transformation. Oxidative effects of UV irradiation exert their influence on melanoma pathogenesis primarily through modification of nucleic acids, proteins, and lipids, further disrupting cellular signaling and cell cycle regulation. Its effects extend beyond melanocytes, leading to immunosuppression in the exposed skin tissue, which consequently creates conditions for immune surveillance evasion and further progression. In this review, we focus on the specific molecular changes observed in the UV-dependent oxidative stress environment and their biological consequences in the course of the disease, which have not been considered in previous reviews on melanoma. Nonetheless, data show that the exact role of oxidative stress in melanoma initiation and progression remains unclear, as it affects cancerous cells differently depending on the specific context. A better understanding of the pathophysiological basis of melanoma development holds promise for identifying potential targets, which could lead to effective melanoma prevention strategies. [ABSTRACT FROM AUTHOR]

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Simple Summary: Animal models are crucial for exploration of the causes of and potential treatments for squamous cell carcinoma, a common type of skin cancer. This study compared four different hairless mouse models to determine which is most suitable for studying skin cancer development when exposed to ultraviolet (UV) light. The models varied in their skin characteristics, such as the presence of melanin, cholesterol level, and immune system function. By monitoring various skin health parameters and analyzing proteasome activity, this study found that the SKH-hr2+ApoE and SKH-hr2 models were the most effective for further research into squamous cell carcinoma. In contrast, the SKH-hr1 model, despite its common use, was less suitable. These findings will help guide future research efforts in understanding and developing treatments for skin cancer. Background: In recent decades, a significant global increase in the incidence of non-melanoma skin cancer has been observed. To explore the pathogenesis of and potential therapeutic approaches for squamous cell carcinoma, various in vivo studies using mouse models have been conducted. However, investigations comparing different hairless mouse models, with or without melanin, as well as models with hypercholesterolemia and immunosuppression, in terms of their ability to induce squamous cell carcinoma have yet to be undertaken. Methods: Four mouse strains, namely SKH-hr1, SKH-hr2, SKH-hr2+ApoE, and immunodeficient Nude (Foxn1 knockout), were exposed to UVA and UVB radiation three times per week, initially to 1 Minimal Erythemal Dose (MED), incrementally increased weekly to a maximum dose of 3 MED. Clinical evaluation, photodocumentation, and biophysical parameters were monitored, along with proteasome protein activity and histopathological assessments. Results: The SKH-hr1 model primarily developed actinic keratosis without significant progression to invasive squamous cell carcinoma (SCC), while the SKH-hr2 and SKH-hr2+ApoE models exhibited a higher likelihood and intensity of papilloma and aggressive SCC formation, with the latter showing upregulated proteasome activity. Histopathological analysis confirmed the presence of poorly differentiated, invasive SCCs in the SKH-hr2 and SKH-hr2+ApoE models, contrasting with the less aggressive SCCs in the Nude mice and the mixed lesions observed in the SKH-hr1 mice. Conclusions: The SKH-hr2+ApoE and SKH-hr2 mice were identified as the most suitable for further exploration of squamous cell carcinogenesis. In contrast, the SKH-hr1 mice were found to be the least suitable, even though they are albino. Notably, proteasome analysis revealed a potential role of proteasome activity in squamous cell carcinogenesis. [ABSTRACT FROM AUTHOR]

Australians have the highest incidence of melanoma globally, despite increasing awareness of the risks of excessive sun exposure. Although excess ultraviolet radiation (UVR) can cause irreparable cell damage and lead to cancer, some exposure is vital to maintain bodily processes such as vitamin D production. For an individual, finding the balance between healthy exposure and skin damage is largely guesswork. The ability to provide a simple, individualised indicator of cumulative UVR dosage could be transformative in preventing skin cancer. This review will provide a brief overview of the variety of UVR sensor technologies and explain the important role of colourimetric dosimeters. The chemistry behind some recent examples of colourimetric dosimeters will be discussed, identifying that molecular photoswitches are ideal candidates to enable this technology. We discuss the chemical mechanisms of photoswitches and how to modify their chemical structure to optimise their properties for use as dosimeters. Through this lens, diarylethenes have been identified as prime dosimeter candidates, owing to their sensitivity, stability, adaptability and the variety of visually striking colours possible. Finally, some specific challenges are identified in the design and fabrication of personalised colourimetric dosimeters that can equitably meet the requirements of all users in our community. Rewearable colourimetric dosimeters offer an efficient, low cost and reusable solution to educate people on their risk from ultraviolet radiation (UVR) from the sun. Molecular photoswitches are a simple chemical technology for creating UVR dosimeters. Key to their translation are enhanced photochemical stability, reusability and overall stability. Beyond the chemistry, it is necessary to design these devices for the needs of all users in our community, to offer equitable protection. (Image credit: Nathan Boase.) [ABSTRACT FROM AUTHOR]

UV light is a portion of the electromagnetic spectrum that ranges from wavelengths of 100 to 400 nm, and in the wavelength range of 100 to 280 nm has germicidal capabilities. UV sterilizers are characterized by a simple and safe use, while also having a high functionality, being types of sterilizers that were created to be easily placed in the most diverse work areas. UV light treatment can be done in two ways; continuous or pulsed; Continuous UV light has several disadvantages, such as poor penetration depth and low dissipation power, while pulsed UV light sterilization has greater penetration depth and dissipation power. In pulsed UV light treatment, energy is stored in a high-power capacitor and released constantly over a short period of time, which produces several types of high-energy ash per second. UV sterilizers are characterized by simple and safe use, while also having a high functionality. These types of sterilizers were created to be easily placed in the most diverse work fields, the wide variety of models and accessories satisfying the needs of all categories of customers. [ABSTRACT FROM AUTHOR]

The estuarine anemone Anthopleura hermaphroditica and its symbiont Philozoon anthopleurum are continuously exposed to intense fluctuations in solar radiation and salinity owing to tidal changes. The aim of this study was to evaluate the effects of the tidal cycle, solar radiation, and salinity fluctuations on the photosynthetic and cellular responses (lipid peroxidation, total phenolic compounds, and antioxidant activity) of the symbiont complex over a 24 h period in the Quempillén River Estuary. Additionally, laboratory experiments were conducted to determine the specific photobiological responses to photosynthetically active radiation (PAR), ultraviolet radiation (UVR), and salinity. Our field results showed that the photosynthetic parameters of the symbiont complex decreased with increasing ambient radiation; however, no relationship was observed with changes in salinity. Increased peroxidative damage, total phenolic compound levels, and antioxidant activity were mainly related to increased UVR and, to a lesser extent, PAR. During the dark period, only PAR-exposed organisms returned to the basal levels of photosynthesis and cell damage. Laboratory exposure confirmed the deleterious effects of UVR on the photosynthetic response. The present study suggests that the ability of A. hermaphroditica to acclimate to natural radiation stress is mediated by the concerted action of various physiological mechanisms that occur at different times of the day, under varying levels of environmental stress. [ABSTRACT FROM AUTHOR]

New active ingredients, including those of plant origin, which could protect the skin against various harmful factors, such as UV radiation and free radicals responsible for skin ageing, are still being sought. The present study was focused on the antioxidant activity of Hippophaë rhamnoides L. and Vaccinium oxycoccos L. fruit glycolic extracts. Investigations were also carried out to evaluate the effect of UVA radiation and the storage of the sea buckthorn and European cranberry extracts at an elevated temperature of 50 °C on their interactions with free radicals. The kinetics of the interactions of the extracts with DPPH were assessed using electron paramagnetic resonance (EPR) spectroscopy. The sea buckthorn and European cranberry extracts quench the EPR signal of DPPH free radicals, which indicates their antioxidant potential. The EPR method further showed that a mixture of sea buckthorn and cranberry extracts in a volume ratio of 2:1 was more potent in quenching free radicals compared to a mixture of these extracts in a ratio of 1:2. Our findings demonstrate that long-term UVA radiation exposure reduces the ability of sea buckthorn and cranberry extracts to interact with free radicals. Moreover, storage at elevated temperatures does not affect the interaction of sea buckthorn extract with free radicals, while it alters the ability of cranberry extract to interact with free radicals. This study has demonstrated that an important factor in maintaining the ability to scavenge radicals is the storage of raw materials under appropriate conditions. H. rhamnoides and V. oxycoccos extracts can be used as valuable raw materials with antioxidant properties in the pharmaceutical and cosmetic industries. [ABSTRACT FROM AUTHOR]

This work presents a 2D radiochromic dosimeter for ultraviolet (UV) radiation measurements, based on cotton fabric volume-modified with nitroblue tetrazolium chloride (NBT) as a radiation-sensitive compound. The developed dosimeter is flexible, which allows it to adapt to various shapes and show a color change from yellowish to purple-brown during irradiation. The intensity of the color change depends on the type of UV radiation and is the highest for UVC (253.7 nm). It has been shown that the developed dosimeters (i) can be used for UVC radiation dose measurements in the range of up to 10 J/cm2; (ii) can be measured in 2D using a flatbed scanner; and (iii) can have the obtained images after scanning be filtered with a medium filter to improve their quality by reducing noise from the fabric structure. The developed cotton–NBT dosimeters can measure UVC-absorbed radiation doses on objects of various shapes, and when combined with a dedicated computer software package and a data processing method, they form a comprehensive system for measuring dose distributions for objects with complex shapes. The developed system can also serve as a comprehensive method for assessing the quality and control of UV radiation sources used in various industrial processes. [ABSTRACT FROM AUTHOR]

The genus Vaccinium is represented by shrubs growing in a temperate climate that have been used for ages as traditional remedies in the treatment of digestive problems, in diabetes, renal stones or as antiseptics due to the presence of polyphenols (anthocyanins, flavonoids and tannins) in their fruits and leaves. Recent studies confirm their marked potential in the treatment of skin disorders and as skin care cosmetics. The aim of this review is to present the role of Vaccinium spp. as cosmetic products, highlight their potential and prove the biological properties exerted by the extracts from different species that can be useful for the preparation of innovative cosmetics. In the manuscript both skin care and therapeutic applications of the representatives of this gender will be discussed that include the antioxidant, skin lightening, UV-protective, antimicrobial, anti-inflammatory, and chemopreventive properties to shed new light on these underestimated plants. [ABSTRACT FROM AUTHOR]

The aim of this work was to develop an innovative tomato cold soup fortified in bioactive compounds through the incorporation of UV-B–treated radish seeds. After a 20 kJ m−2 UV-B treatment, radish seeds increased their sulforaphene content by 30%. Different concentrations of UV-B–treated seeds (0, 0.5, 1.5, 3, and 5 g kg−1) were added to a chopped vegetables cold soup, mainly made of Kumato® cherry tomatoes as novelty, including pepper, cucumber, and garlic, which was stored for 8 days at 4 °C. Added seeds did not affect physicochemical quality attributes, microbial growth, nor sensory perception. Nevertheless, a dose-dependent behaviour was shown in glucoraphenin and sulforaphene content, according to concentrations of UV-B–treated seeds added. It was also appreciated after an in vitro digestion that the bioaccessible fraction of glucosinolates and isothiocyanates was kept constant throughout the refrigerated storage. The sulforaphene content of the soup increased by ~ 19% after 2 days at 4 °C, of which the 33% was bioaccessible (measured in vitro), and subsequently was degraded by ~ 20% after 8 days at 4 °C. [ABSTRACT FROM AUTHOR]

Asphalt binders in pavements lose their stability through aging and eventually fail in the field. Using nuclear magnetic resonance (NMR) to monitor the primary longitudinal relaxation time of asphalt samples and the ratio of material that carries this primary relaxation time has been shown to indicate the impact of ultraviolet (UV) radiation on the aging of asphalt pavements. Longitudinal NMR relaxation was used to investigate two types of proposed asphalt rejuvenators, a bio-oil-based rejuvenator and a crude-oil-based rejuvenator. Two different binders with the performance grades (PG) 64-22 and 76-22 were considered for their interactions with the rejuvenators. After 72 h of exposure to intense UV radiation, specifically designed NMR relaxometry experiments were applied to compare the rejuvenation capabilities of the two rejuvenator samples. The crude oil-based rejuvenator was found to exhibit relaxation times similar to the binder samples while the bio-based material showed relaxation times that pointed to different nuclear hydrogen environments. Both rejuvenators reduced the primary relaxation time of the PG 76-22 binder, which indicates that their stiffness was reduced. Both types of rejuvenators also seemed to prevent the effects of UV aging. Two mechanisms of rejuvenation were identified by NMR relaxometry. The primary relaxation time can be used to indicate a change in stiffness while the primary ratio of the material is tied to oxidative aging. Oxidative aging creates distinct hydrogen environments due to asphaltene aggregation. The bio-based rejuvenator only reduced the binder's stiffness, while the crude oil-based rejuvenator also reduced the aggregation of asphaltenes. Consequently, the bio-based rejuvenator could be classified as an asphalt softener, while the oil-based material acted like a true rejuvenator. [ABSTRACT FROM AUTHOR]

This paper describes the behavior of some epoxy, acrylic and polyurethane paints used in the protection of electrical equipment under the action of different degradation factors. The degradation factors chosen were temperature and UV radiation. The behavior of the paints under the action of these factors was interpreted by the variation of the tangent of the dielectric loss angle (tg Delta) as well as by FTIR and TG DSC analyses. Tg Delta was considered the reference dielectric characteristic because it best simulates the functionality of the material. The results presented in this paper lead to the conclusion that exposure to thermal cycles and UV radiation is necessary for each paint to give indications about their possibility of use in these conditions. At the same time, the evaluation of thermal stability, even if the exposure is at lower temperatures (than those at which we performed the tests) and/or for shorter periods, is very important for placing the paint in an insulation class. The tests that were the subject of this work provide us with the following information about the three types of paints analyzed: the highest resistance to thermal cycles is presented by S3, followed by S2 and then S1; thermal endurance tests place the polyurethane paint (S3) in insulation class E and the epoxy paint (S1) in insulation class B; and the tests to determine resistance to UV radiation qualify the best paint as acrylic (S2) and the worst as polyurethane (S3). Thus, it can be said that in applications where it is necessary for the protective film to withstand high temperatures, the use of S3 paint (polyurethane) is recommended, and in applications where the films are kept under the influence of UV radiation for a longer time, it is recommended to use coded paint S2 (acrylic). The results presented in this paper lead to the conclusion that the exposure to thermal cycles simulating the use in outdoor conditions and the resilience of paints under UV radiation conditions must be performed for each paint according to its specific use, and the dielectric characteristics must be carefully evaluated because they can reach values under the accepted limit—e.g., thermal stability evaluation—even if the exposure is at lower temperatures and/or for shorter periods. The conclusions of the experimental work must be generalized at different types of electrical insulating paints, and maybe a new standard is necessary to assess the paints' behavior under usage conditions, with the paints needing to be treated separately from the classical polymeric insulation systems. [ABSTRACT FROM AUTHOR]

The examines how the size of submicron zinc oxide particles impacts the ultraviolet (UV) protection properties of textiles, particularly cotton. It explores the relationship between particle size and the ability of textiles to block UV radiation, emphasizing that while smaller particle sizes can enhance UV protection within a specific range, there are optimal sizes that maximize this effect.

UV ray is an unavoidable environmental factor in the operation of outdoor cable accessories, which is easy to cause the cable accessories flashover and breakdown faults. In this paper, the changes of insulation properties of silicone rubber (SiR) after UV radiation treatment were studied from the aspects of microstructure, dielectric properties, surface properties and discharge properties. Combined with the analysis of molecular chain damage and surface trap, the influence mechanism of UV radiation on the insulation properties of SiR was revealed. The experimental results show that the dielectric constant of SiR after UV radiation treatment first decreases and then increases, it decreases to 3.06 at 240 h and increases to 3.93 at 1000 h. UV radiation can reduce the surface resistance of SiR, it decreases by 48% after 1000 h radiation. With the extension of UV radiation time, the surface trap level corresponding to the peak of the trap density is about 0.95 eV, the trap density decreases to 2.32 × 1022 eV−1 m−3 at 240 h. Short-term UV radiation can promote the secondary cross-linking of SiR, resulting in the increase of flashover voltage from 6.32 to 7.64 kV. Long-term radiation can destroy the molecular chain structure, resulting in a slight decrease in the flashover voltage. With the extension of UV radiation time, the breakdown strength decreases by about 14% at 1000 h. This work has guiding significance for the radiation performance and life evaluation of cable accessories. [ABSTRACT FROM AUTHOR]

Litter's chemical complexity influences carbon (C) cycling during its decomposition. However, the chemical and microbial mechanisms underlying the divergence or convergence of chemical complexity under UV radiation remain poorly understood. Here, we conducted a 397-day field experiment using 13C cross-polarization magic-angle spinning nuclear magnetic resonance (13C-CPMAS NMR) to investigate the interactions among the initial chemistry, microbial communities, and UV radiation during decomposition. Our study found that the initial concentrations of O-substituted aromatic C, di-O-alkyl C, and O-alkyl C in Deschampsia caespitosa were higher than those in Kobresia tibetica. Litter's chemical composition exhibited divergent patterns based on the initial chemistry, UV radiation, and decay time. Specifically, D. caespitosa consistently displayed higher concentrations of di-O-alkyl C and O-alkyl C compared to K. tibetica, regardless of the UV exposure and decay time. Additionally, litter's chemical complexity was positively correlated with changes in the extracellular enzyme activities, particularly those involved in lignin, cellulose, and hemicellulose degradation, which accounted for 9%, 20%, and 4% of the variation in litter's chemical complexity, respectively. These findings highlighted the role of distinct microbial communities in decomposing different C components through catabolism, leading to chemical divergence in litter. During the early decomposition stages, oligotrophic Planctomycetes and Acidobacteria metabolized O-alkyl C and di-O-alkyl C under UV-blocking conditions. In contrast, copiotrophic Actinobacteria and Chytridiomycota utilized these components under UV radiation exposure, reflecting their ability to thrive under UV stress conditions due to their rapid growth strategies in environments rich in labile C. Our study revealed that the inherent differences in the initial O-alkyl C and di-O-alkyl C contributed to the chemical divergence, while UV radiation further influenced this divergence by shifting the microbial community composition from oligotrophic to copiotrophic species. Thus, differences in the initial litter chemistry, microbial community, and UV radiation affected the quantity and quality of plant-derived C during decomposition. [ABSTRACT FROM AUTHOR]

Melasma, also known as chloasma and the "mask of pregnancy", is a common acquired pigmentary disorder characterized by irregular, hyperpigmented brown-to-grey patches primarily situated on the face. It typically affects women of reproductive age, especially those exhibiting Fitzpatrick skin types III to V. The precise etiopathogenesis of melasma is complex and has not been fully elucidated; however, ultraviolet radiation, hormonal factors, and genetic predispositions significantly contribute to the melanin production increase associated with this condition. Due to the multifactorial aetiology, resistance to various therapeutic options, and high recurrence rate, treating melasma is challenging. Hydroquinone has long been considered a gold standard in melasma treatment due to its ability to inhibit tyrosinase; however, it has faced scrutiny after concerns about its adverse effects. Current treatment strategies include various topical and systemic therapies, procedural interventions, as well as combinations of these methods. For optimal results, both photoprotection and a treatment plan that targets different pathogenic mechanisms should be used. Additionally, treatment should be tailored to patient characteristics, such as skin type, the severity of the condition, and compliance. This review summarises current treatment options, focusing on long-term therapy and the latest advancements in managing this challenging condition. [ABSTRACT FROM AUTHOR]

This study evaluated the health-related weighted ultraviolet radiation (UVR) due to the total ozone content (TOC) and the aerosol optical depth (AOD) changes. Clear-sky Ultraviolet Index (UVI), daily doses, and exposure times for erythema induction (Dery and Tery) and vitamin D synthesis (DvitD and TvitD) were computed by a radiative transfer estimator. TOC and AOD data were provided by six Earth System Models (ESMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6). For projections, we consider four Shared Socioeconomic Pathways scenarios—SSPs (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5)—and two time-slices (near: 2041–2060 and far future: 2081–2100). UVR projections showed pronounced changes for the summer hemispheres in the far future. TOC increases in mid- and high latitudes of the Southern Hemisphere caused decreases in UVR at the summer solstice. However, projections did not indicate sun-safe exposure conditions in South America, Australia, and Southern Africa. On the contrary, exposure around solar noon from 10 to 20 min will still be sufficient to induce erythema in skin type III individuals throughout this century. In southern Argentina and Chile, the UVR insufficiency for vitamin D synthesis at solar noon in skin type III remains the same during this century at the winter solstice. In the Northern Hemisphere, UVI and Dery at the summer solstice should remain high (UVI ≥ 8; Dery ~ 7.0 kJ m−2) in highly populated locations. Above 45 °N, UVR levels cannot be enough to synthesize vitamin D in skin type III during the boreal winter. Our results show that climate change will affect human health through excess or lack of solar UVR availability. [ABSTRACT FROM AUTHOR]

Background: Rosacea is a chronic inflammatory skin condition that can be exacerbated by various environmental factors. This study aimed to investigate the impact of UV radiation, temperature, humidity, and air pollution on rosacea severity and quality of life over a one-year period. Methods: A prospective observational study was conducted with 100 adult rosacea patients. Rosacea severity (assessed using the National Rosacea Society Expert Committee grading system) and quality of life (assessed using the Dermatology Life Quality Index) were evaluated at baseline and every three months for one year. Participants kept daily diaries of their exposure to environmental factors. Results: Significant associations were found between environmental factors and rosacea severity. UV radiation (coefficient 0.18, 95% CI 0.10-0.26, p<0.001), temperature (coefficient 0.14, 95% CI 0.08-0.20, p<0.001), humidity (coefficient 0.09, 95% CI 0.03-0.15, p=0.004), and air pollution (coefficient 0.12, 95% CI 0.06-0.18, p<0.001) were all significantly associated with increased rosacea severity. Rosacea severity scores decreased significantly from baseline to each follow-up visit (p<0.001), and quality of life scores improved significantly (p<0.001). Subgroup analyses revealed consistent findings across age groups, genders, and rosacea subtypes. Conclusion: Exposure to UV radiation, high temperatures, humidity, and air pollution were significantly associated with increased rosacea severity and reduced quality of life. These findings emphasize the importance of environmental factor management in the treatment and prevention of rosacea flare-ups. [ABSTRACT FROM AUTHOR]

Recent studies have highlighted the crucial role of abiotic processes, such as photodegradation and microclimatic fluctuation, in accelerating dryland litter decomposition. In grasslands, substantial amounts of dead plant material persist upright above the soil surface after senescence, experiencing distinct microclimatic conditions compared to surface litter. However, our understanding of how ultraviolet (UV) exposure and microclimatic conditions influence their decomposition is limited. To address this knowledge gap, we conducted a field experiment manipulating UV radiation for both soil surface litter and standing litter and monitored their microclimatic conditions in a semi‐arid grassland. Our findings indicate that UV exposure enhanced the decomposition of soil surface litter by alleviating the constraint of lignin on litter decomposition, while having no significant influence on standing litter. Although the mean levels of thermal‐hydric conditions were lower, more intense fluctuation of temperature and air humidity was detected in standing litter. These higher‐level microclimatic fluctuations facilitated the release of dissolved organic carbon, potentially increasing the availability of labile substrates to microbes. Meanwhile, standing litter released more photo‐sensitive phenols, leading to decreased sensitivity to UV exposure. Consequently, while UV exposure initially increased standing litter decomposition during the early stage, its influence eventually diminished. These findings underscore the critical yet differing roles of microclimatic conditions and UV exposure in the decomposition of standing and surface litter. Relying solely on knowledges derived from surface litter decomposition and microclimate conditions may not accurately capture the patterns of grassland litter degradation. Plain Language Summary: The limited precipitation in drylands is widely believed to restrict litter decomposition. However, the observed litter decomposition rates in these regions often exceed model predictions based on climatic conditions. In arid and semi‐arid steppes, the sparse vegetation cover results in intense ultraviolet (UV) radiation reaching soil surface, thereby triggering photodegradation of the recalcitrant compounds in litter. Additionally, substantial dead plant materials persist standing for months to years, and undergoes more intense warm‐cold and wet‐dry cycles. However, there have been limited studies assessing the intricate interplay between UV radiation and microclimate fluctuations on litter decomposition in drylands. In this study, we found that UV radiation facilitated the degradation of recalcitrant compounds and enhanced litter degradability of soil surface litter. More intense temperature and humidity fluctuations increased the concentration of dissolved organic carbon in standing litter. This increase could provide more labile substrate to decomposers, consequently accelerating litter decomposition. Moreover, microclimatic fluctuation enhances the loss of photo‐sensitive compounds in litter, reducing litter's sensitivity to UV exposure. Our study highlighted the significant role played by the interaction between climatic conditions and UV radiation in driving litter decomposition in water‐limited steppes, contributing to a better understanding of carbon turnover in dryland ecosystem. Key Points: The degradation of soil surface litter was mainly driven by warmer and wetter microclimate and ultraviolet (UV) exposureGreater microclimatic fluctuation in standing litter enhanced the release of dissolved labile carbon, thereby accelerating its decompositionGreater microclimatic fluctuation increased the loss of photo‐sensitive compound and weakened sensitivity of standing litter to UV radiation [ABSTRACT FROM AUTHOR]

The zygnematophytes are the closest relatives of land plants and comprise several lineages that adapted to a life on land. Species of the genus Serritaenia form colorful, mucilaginous capsules, which surround the cells and block harmful solar radiation, one of the major terrestrial stressors. In eukaryotic algae, this 'sunscreen mucilage' represents a unique photoprotective strategy, whose induction and chemical background are unknown. We generated a de novo transcriptome of Serritaenia testaceovaginata and studied its gene regulation under moderate UV radiation (UVR) that triggers sunscreen mucilage under experimental conditions. UVR induced the repair of DNA and the photosynthetic apparatus as well as the synthesis of aromatic specialized metabolites. Specifically, we observed pronounced expressional changes in the production of aromatic amino acids, phenylpropanoid biosynthesis genes, potential cross-membrane transporters of phenolics, and extracellular, oxidative enzymes. Interestingly, the most up-regulated enzyme was a secreted class III peroxidase, whose embryophyte homologs are involved in apoplastic lignin formation. Overall, our findings reveal a conserved, plant-like UVR perception system (UVR8 and downstream factors) in zygnematophyte algae and point to a polyphenolic origin of the sunscreen pigment of Serritaenia , whose synthesis might be extracellular and oxidative, resembling that of plant lignins. [ABSTRACT FROM AUTHOR]

Photonic synapses integrate sensing and processing within a single device, making them promising candidates for emulating the visual perception of a biological retina. Most retinomorphic photonic synapses achieve image pre‐processing by differentially responding to red, green, and blue (RGB). However, the impact of invisible ultraviolet (UV) light on the retina remains insufficiently explored, hindering the perception of the full spectrum by retinomorphic devices. Herein, a photonic synapse is constructed with strong UV absorption of Poly[(9,9‐dioctylfluorenyl‐2,7‐diyl)‐co‐(4,4′‐(N‐(4‐sec‐butylphenyl) diphenylamine)] (TFB) as photosensitive layer. The device exhibits synaptic properties of long‐term memory (LTM) and short‐term memory (STM) at different UV radiation stages. Extracting the electrical conductance of the device under UV radiation generates patterns of different resolutions, facilitating the simulation of retinal damage's impact on object perception. Moreover, an electronic eye system, incorporating the photonic synapse under UV radiation, successfully replicates pupil constriction and eye‐closing behaviors akin to those observed in a real biological eye. This result underscores the authenticity of retinomorphic devices, expending a novel concept for the future development of visuomorphic computing. [ABSTRACT FROM AUTHOR]

Data on the sensitivity of Ga2O3/GaAs:Cr heterostructures are presented to long-wave and UV (λ = 254 nm) radiation. The samples were obtained by RF magnetron sputtering of a gallium oxide film on non-heated GaAs:Cr substrates. Gallium arsenide plates with a Ga2O3 film were divided into two parts: one half was not annealed, and the other was annealed in argon at 500°C for 30 min. Regardless of the presence or absence of heat treatment, the studied structures exhibit a photovoltaic effect and are able to operate in an autonomous mode. It is shown that a noticeable sensitivity to long-wave radiation appears in the samples only after thermal annealing of gallium oxide films. The response and recovery times of such UV radiation detectors do not exceed 1 second. [ABSTRACT FROM AUTHOR]

The need to develop advanced wastewater treatment techniques and their use has become a priority, the main goal being the efficient removal of pollutants, especially those of organic origin. This study presents the photo-degradation of a pharmaceutical wastewater containing Kabi cytarabine, using ultraviolet (UV) radiation, and a synthesized catalyst, a composite based on bismuth and iron oxides (BFO). The size of the bandgap was determined by UV spectroscopy, having a value of 2.27 eV. The specific surface was determined using the BET method, having a value of 0.7 m2 g−1. The material studied for the photo-degradation of cytarabine presents a remarkable photo-degradation efficiency of 97.9% for an initial concentration 0f 10 mg/L cytarabine Kabi when 0.15 g of material was used, during 120 min of interaction with UV radiation at 3 cm from the irradiation source. The material withstands five photo-degradation cycles with good results. At the same time, through this study, it was possible to establish that pyrimidine derivatives could be able to combat infections caused by Escherichia coli and Candida parapsilosis. [ABSTRACT FROM AUTHOR]

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In our study, we investigated the accelerated aging process of PLA under 253.7 nm UV-C irradiation with the use of the GPC, NMR, FTIR, and DSC methods and formal kinetic analysis. The results of GPC and DSC indicated a significant degree of destructive changes in the PLA macromolecules, while spectroscopic methods NMR and FTIR showed maintenance of the PLA main structural elements even after a long time of UV exposure. In addition to that, the GPC method displayed the formation of a high molecular weight fraction starting from 24 h of irradiation, and an increase in its content after 144 h of irradiation. It has been shown for the first time that a distinctive feature of prolonged UV exposure is the occurrence of intra- and intermolecular radical recombination reactions, leading to the formation of a high molecular weight fraction of PLA decomposition products. This causes the observed slowdown of the photolysis process. It was concluded that photolysis of PLA is a complex physicochemical process, the mechanism of which depends on morphological changes in the solid phase of the polymer under UV radiation. [ABSTRACT FROM AUTHOR]

Nonmetallic ionic liquids (ILs) exhibit unique advantages in catalyzing poly (ethylene terephthalate) (PET) glycolysis, but usually require longer reaction times. We found that exposure to UV radiation can accelerate the glycolysis reaction and significantly reduce the reaction time. In this work, we synthesized five nonmetallic dibasic ILs, and their glycolysis catalytic activity was investigated. 1,8-diazabicyclo [5,4,0] undec-7-ene imidazole ([HDBU]Im) exhibited better catalytic performance. Meanwhile, UV radiation is used as a reinforcement method to improve the PET glycolysis efficiency. Under optimal conditions (5 g PET, 20 g ethylene glycol (EG), 0.25 g [HDBU]Im, 10,000 µW·cm−2 UV radiation reacted for 90 min at 185 °C), the PET conversion and BHET yield were 100% and 88.9%, respectively. Based on the UV-visible spectrum, it was found that UV radiation can activate the C=O in PET. Hence, the incorporation of UV radiation can considerably diminish the activation energy of the reaction, shortening the reaction time of PET degradation. Finally, a possible reaction mechanism of [HDBU]Im-catalyzed PET glycolysis under UV radiation was proposed. [ABSTRACT FROM AUTHOR]

In recent years, non-thermal plasma (NTP) has emerged as a promising tool for decontamination and disinfection within the food industry. Given the increasing resistance of microbial biofilms to conventional disinfectants and their adverse environmental effects, this method has significant potential for eliminating biofilm formation or mitigating the metabolic activity of grown biofilms. A comparative study was conducted evaluating the efficacy of UV radiation and NTP in eradicating mature biofilms of four common foodborne filamentous fungal contaminants: Alternaria alternata, Aspergillus niger, Fusarium culmorum, and Fusarium graminearum. The findings reveal that while UV radiation exhibits variable efficacy depending on the duration of exposure and fungal species, NTP induces substantial morphological alterations in biofilms, disrupting hyphae, and reducing extracellular polymeric substance production, particularly in A. alternata and F. culmorum. Notably, scanning electron microscopy analysis demonstrates significant disruption of the hyphae in NTP-treated biofilms, indicating its ability to penetrate the biofilm matrix, which is a promising outcome for biofilm eradication strategies. The use of NTP could offer a more environmentally friendly and potentially more effective alternative to traditional disinfection methods. [ABSTRACT FROM AUTHOR]

In this paper, we describe conversion factors (CF) for the calculation of biologically effective irradiances (BEI) from erythemal irradiance for three effects: photosynthesis of previtamin D3, psoriasis healing, and inactivation of the SARS-Cov-2 virions. CFs were empirically derived from measurements of spectral solar ultraviolet (UV) radiation during all sky conditions at four mid-latitude sites in the Northern Hemisphere, namely Aosta, Belsk, Reading, and San Diego. These CFs were found to depend on solar zenith angle (SZA) and total column ozone, but are largely independent (within ± 5% for SZA < 60°) of local conditions such as surface albedo, visibility and other local atmospheric patterns. The values of these empirical CFs are consistent with analytical CFs derived with radiative transfer calculations (model FastRT) for clear-sky and overcast conditions. To validate these analytical CFs, one-hour radiant exposures for the three biological effects were calculated from erythemal measurements at Reading between 2012 and 2021 and compared with similar exposures calculated directly from the spectral UV measurements. The two datasets agreed within 10% for SZA < 65°, demonstrating the utility of the conversion method. These results suggest that the proposed analytical CFs can be used with confidence to estimate radiant exposures for the three biological effects from measurements of the UV Index at any northern mid-latitude site. [ABSTRACT FROM AUTHOR]

A lot of research is constantly underway in the world to develop new or improve the current processes of the chemical industry to make them more effective and environmentally friendly. The described research on the oxidation of cyclohexane or cyclohexanone to adipic acid with a coupled action of UV radiation and oxygen–ozone mixture, instead of the currently used oxidation with HNO3, is part of this trend. Gas chromatography was used to determine process indicators, such as cyclohexane conversion and selectivity to AA, which exceeded 50% at 25 oC, after 16 h. This method can also be used for the preparation of other dicarboxylic acids from cycloalkanes, which proves its universal character. [ABSTRACT FROM AUTHOR]

Astaxanthin (AX) is known as a very strong antioxidant and has been utilised in many kinds of products such as foods, pharmaceutical, cosmetics, aquaculture, etc. One of the natural resources of AX is Haematococcus pluvialis which has been investigated by some researchers in order to enhance the AX production. However, the production of AX from the microalgae is still costly, hence, this present research is proposing low-cost methods namely bean sprout media (BSM) as an alternative growth media and UV radiation. The variations of BSM concentrations (2, 4, and 6 %) and times of UV radiation (1.5 and 3 hrs) were treated to H. pluvialis in laboratory conditions. BSM 4 % treatment showed an optimum growth of the microalga at 427 x 104 cell/ml (day 8) which also exhibited macrozooid, palmella, and aplanosore phases. UV radiation for 3 hr revealed that the concentration of AX production was as much as 17.37±0.04 mg/l. The research results were potential to be developed further in order to discover better and cheaper methods for scaling up AX production. [ABSTRACT FROM AUTHOR]

Resistive metal/β-Ga2O3/metal structures with different interelectrode distances and electrode topologies were investigated. The oxide films were deposited by radio-frequency magnetron sputtering of a Ga2O3 (99.999%) target onto an unheated sapphire c-plane substrate (0001) in an Ar/O2 gas mixture. The films are sensitive to ultraviolet radiation with wavelength λ = 254. Structures with interdigital electrode topology have pronounced persistent conductivity. It is shown that the magnitude of responsivity, response time τr, and recovery time τd are determined by the concentration of free holes p involved in recombination processes. For the first time, it is proposed to consider hole trapping both by surface states Nts at the metal/Ga2O3 interface and by traps in the bulk of the film. [ABSTRACT FROM AUTHOR]

Avobenzone is one of the most widely used sunscreens in skin care formulations, but suffers from some drawbacks, including photo instability. To mitigate this critical issue, the use of octocrylene as a stabilizer is a common approach in these products. However, octocrylene has been recently demonstrated to show potential phototoxicity. The aim of this work is to analyze the performance of a series of mycosporine-like amino acid (MAA)-inspired compounds to act as avobenzone stabilizers as an alternative to octocrylene. Different avobenzone/MAA analogue combinations included in galenic formulations were followed under increasing doses of solar-simulated UV radiation. Some of the synthetic MAA analogues analyzed were able to increase by up to two times the UV dose required for 50% of avobenzone photobleaching. We propose some of these MAA analogues as new candidates to act as avobenzone-stabilizing compounds in addition to their UV absorbance and antioxidant properties, together with a facile synthesis. [ABSTRACT FROM AUTHOR]

In this study, we aimed to document the freshwater symbiotic interactions along with the impact of the abiotic environment and anthropogenic effects on the functionality of freshwater organisms. Symbiotic green hydra (Z) and free-living brown hydra (S), either separately or both species together, were treated with the herbicide norflurazon in concentrations of 2 × 10−6 mol/L (N6) and 2 × 10−7 mol/L (N7) for 72 h. Also, hydras were treated with both norflurazon and UV radiation at a wavelength of 254 nm for 2 min or were irradiated only. The next part of the experiment was performed in the same way but with added suspensions of isolated endosymbiotic alga, free-living alga, or both algae together. Mortality, migration, tentacle and tissue damage, changes in the thickness of the mesoglea of hydras, and clustering of algae were monitored. Green hydra generally showed lower rates of migration, and mortality was observed only in green hydra exposed to UV radiation. Tentacle damage was more pronounced in green hydra and included a specific fork-like structure. The use of cryofixation and TEM enabled us to partly elucidate the effect of clustering of algae. In summary, our study provides new insights into the influence of different environmental stressors and their combination on symbiotic and free-living freshwater hydras and algae and a better understanding of interactions in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Photochemical reactions in cell DNA are induced in various organisms by solar UV radiation and may lead to a series of biological responses to DNA damage, including apoptosis, mutagenesis, and carcinogenesis. The chemical nature and the amount of DNA lesions depend on the wavelength of UV radiation. UV type B (UVB, 290–320 nm) causes two main lesions, cyclobutane pyrimidine dimers (CPDs) and, with a lower yield, pyrimidine (6-4) pyrimidone photoproducts (6-4PPs). Their formation is a result of direct UVB photon absorption by DNA bases. UV type A (UVA, 320–400 nm) induces only cyclobutane dimers, which most likely arise via triplet–triplet energy transfer (TTET) from cell chromophores to DNA thymine bases. UVA is much more effective than UVB in inducing sensitized oxidative DNA lesions, such as single-strand breaks and oxidized bases. Of the latter, 8-oxo-dihydroguanine (8-oxodG) is the most frequent, being produced in several oxidation processes. Many recent studies reported novel, more detailed information about the molecular mechanisms of the photochemical reactions that underlie the formation of various DNA lesions. The information is mostly summarized and analyzed in the review. Special attention is paid to the oxidation reactions that are initiated by reactive oxygen species (ROS) and radicals generated by potential endogenous photosensitizers, such as pterins, riboflavin, protoporphyrin IX, NADH, and melanin. The review discusses the role that specific DNA photoproducts play in genotoxic processes induced in living systems by UV radiation of various wavelengths, including human skin carcinogenesis. [ABSTRACT FROM AUTHOR]

This study aimed to explore the published research on the relationship between climate change and skin cancer and the implications for prevention, management and further research. Scoping review. This scoping review following JBI methodology reviewed English articles identified in searches of MEDLINE, Embase, CINAHL, Web of Science and Scopus on 14 April 2023. The screening of articles was completed by two independent reviewers. Data were extracted by a single reviewer and checked by another. A causal pathway diagram was iteratively developed throughout the review and was used to categorise the findings. The search identified 1376 papers, of which 45 were included in the final review. Nine papers reported primary research, and 36 papers were reviews, perspectives, commentaries, editorials, or essays. The papers examined climate change influencing behaviours related to ultraviolet exposure (30 papers), ambient temperature (21 papers) and air pollution (five papers) as possible risk factors; occupational, rural, and contextual factors affecting skin cancer (11 papers); and prevention and access to health care in the context of climate change (seven papers). Most papers were published in journals in subject areas other than health. This review identified ultraviolet radiation, occupation, rising temperature, individual behaviour and air pollution as possible influences on skin cancer rates. Furthermore, it highlights the complexity and uncertainties in the relationship between climate change and skin cancer and the need for further research on this relationship, including primary epidemiological research and reviews that follow recognised review guidelines and include assessment of health services and social determinants in the causal pathways of this relationship. [ABSTRACT FROM AUTHOR]

This study presents the effect of ultra-violet (UV) light radiation on the process kinetics, metabolic performance, and biodegradation capability of Scenedesmus vacuolatus. The impact of the UV radiation on S. vacuolatus morphology, chlorophyll, carotenoid, carbohydrates, proteins, lipid accumulation, growth rate, substrate affinity and substrate versatility were evaluated. Thereafter, a preliminary biodegradative potential of UV-exposed S. vacuolatus on spent coolant waste (SCW) was carried out based on dehydrogenase activity (DHA) and total petroleum hydrocarbon degradation (TPH). Pronounced structural changes were observed in S. vacuolatus exposed to UV radiation for 24 h compared to the 2, 4, 6, 12 and 48 h UV exposure. Exposure of S. vacuolatus to UV radiation improved cellular chlorophyll (chla = 1.89-fold, chlb = 2.02-fold), carotenoid (1.24-fold), carbohydrates (4.62-fold), proteins (1.44-fold) and lipid accumulations (1.40-fold). In addition, the 24 h UV exposed S. vacuolatus showed a significant increase in substrate affinity (1/Ks) (0.959), specific growth rate (µ) (0.024 h−1) and biomass accumulation (0.513 g/L) by 1.50, 2 and 1.9-fold respectively. Moreover, enhanced DHA (55%) and TPH (100%) degradation efficiency were observed in UV-exposed S. vacuolatus. These findings provided major insights into the use of UV radiation to enhance S. vacuolatus biodegradative performance towards sustainable green environment negating the use of expensive chemicals and other unfriendly environmental practices. [ABSTRACT FROM AUTHOR]

The aim was to determine the response of a bloom-forming Microcystis aeruginosa to climatic changes. Cultures of M. aeruginosa FACHB 905 were grown at two temperatures (25°C, 30°C) and exposed to high photosynthetically active radiation (PAR: 400-700 nm) alone or combined with UVR (PAR + UVR: 295-700 nm) for specified times. It was found that increased temperature enhanced M. aeruginosa sensitivity to both PAR and PAR + UVR as shown by reduced PSII quantum yields (Fv/Fm) in comparison with that at growth temperature (25°C), the presence of UVR significantly exacerbated the photoinhibition. M. aeruginosa cells grown at high temperature exhibited lower PSII repair rate (Krec) and sustained nonphotochemical quenching (NPQs) induction during the radiation exposure, particularly for PAR + UVR. Although high temperature alone or worked with UVR induced higher SOD and CAT activity and promoted the removal rate of PsbA, it seemed not enough to prevent the damage effect from them showing by the increased value of photoinactivation rate constant (Kpi). In addition, the energetic cost of microcystin synthesis at high temperature probably led to reduced materials and energy available for PsbA turnover, thus may partly account for the lower Krec and the declination of photosynthetic activity in cells following PAR and PAR + UVR exposure. Our findings suggest that increased temperature modulates the sensitivity of M. aeruginosa to UVR by affecting the PSII repair and defense capacity, thus influencing competitiveness and abundance in the future water environment. [ABSTRACT FROM AUTHOR]

As the prevalence of electromagnetic interference (EMI) continues to rise, there is a growing demand for shielding materials, which play a crucial role in electronic devices, communication systems, health protection, etc. However, conventional EMI shielding materials encounter difficulties in effectively addressing the escalating intricacies of electromagnetic environments and diverse shielding scenarios, wherein foldability, flexibility, and lightweight are desired. In this work, a novel EMI shielding material, silver‐hollow‐fiber (AgHF), is developed by combining blow‐spinning, UV radiation, and temperature‐controlled annealing technologies. During the fabrication process, UV radiation is used to selectively reduce silver ions on the outer surface of precursor fiber, and temperature‐controlled annealing is further employed to remove the inside polymer, forming a hollow fiber structure. The AgHF exhibits superior flexibility, lightweight, remarkable mechanical stability, and excellent EMI shielding efficiency (SE). Particular, the AgHF with a thickness of 163 µm demonstrates an EMI SE of 101.65 dB, and with minimal degradation of less than 10% even after undergoing 2000 bending cycles. The remarkable EMI shielding performance, combined with the lightweight, flexibility, and mechanical stability of AgHF, positions it as a highly promising material for a wide range of EMI shielding applications in the future. [ABSTRACT FROM AUTHOR]

Recently it was purported that autofluorescence (AF) in Paramacrobiotus n. sp. provided protection from UV radiation. If true, this would be the first documentation of an adaptive function for AF in any microscopic animal. We review what is currently known about AF in tardigrades, and we provide the first true colour images of tardigrade fluorescence. To assess the hypothesis of AF as UV protection we measured interspecific variation and intraspecific variation. We found that interspecific variation was much greater than intraspecific variation. We compared the fluorescence emission spectra for nine species of tardigrades, and together with the true colour fluorescence images, we noticed different patterns of fluorescence suggesting a rich diversity of fluorophores. We examined epidermal pigments of a new species of Milnesium and Ramazzottius kretschmanii and found that they are not the source of fluorescence in these species. We suggest further research is necessary to test the hypothesis that AF is UV protective in tardigrades, and we demonstrate and assess four different research tools for examining autofluorescence in microscopic animals. [ABSTRACT FROM AUTHOR]

The influence of UV-Vis and monochromatic radiation (λ = 408 nm) on the reactions of copper sulfate (CuSO4) and copper(II) oxide (CuO) with β-diketones, chelators, and dicarboxylic acids was studied. The reactions of CuSO4 and CuO with Trilon B and succinic acid in aqueous media in the presence of urea occurred faster by using UV-Vis radiation. UV radiation accelerated the reaction of CuSO4 with H4edta in aqueous MeCN. Monochromatic radiation hastened the reaction of CuO with Trilon B and H4edta in aqueous and MeCN media. Eight reactions that were significantly accelerated by electromagnetic radiation were found. [ABSTRACT FROM AUTHOR]

Fucalean algae are dominant canopy-forming species that create extensive and highly productive ecosystems in the intertidal and subtidal rocky shores of temperate seas. Regrettably, these marine forests are in decline due to various human drivers, with the Mediterranean Sea one of the most threatened areas. To design appropriate restoration strategies adapted to cope with the unavoidable change in future climate conditions, the response to climate change of the candidate species must be considered. It is important to assess how the specific life history traits of the foundational species may determine environmental requirements, and thus responses to future climate change. This knowledge will allow us to predict the potential winners and losers among the species potentially inhabiting the same areas in a future context of global climate change, providing important information to fine-tune future restoration interventions. The aim of this study was to evaluate the response of two canopy-forming species inhabiting similar upper subtidal zones but with different life history traits to a combination of anomalous high temperatures and increased UV radiation. One of the species (Ericaria crinita) was perennial, slightly exposed rocky shores and dwelling in areas where extreme temperatures can be frequent; while the other (Ericaria mediterranea) a semi-perennial species that dwells in waveexposed zones, with seawater temperatures buffered by the high hydrodynamism. Our results show that the effects of temperature and radiation are species- (mediated by the species life history traits) and life-stage specific. High temperatures strongly affected the adults of both species, especially E. mediterranea. The germlings in addition to being very susceptible to high temperatures, were also vulnerable to UV radiation, exacerbating the impacts of temperature, especially on E. crinita recruits. Interestingly, vulnerability to climate-driven impacts was determined by the specific life history traits, with i) the species dwelling in open areas the most sensitive to warming and, ii) the perennial species the most vulnerable to UV radiation. Last, we discuss how these species-specific responses to climate-driven impacts may be key in terms of species that could foster the resistance and resilience of marine ecosystems to future climate impacts. [ABSTRACT FROM AUTHOR]

It is well established that UV radiation can inactivate bacteria by destroying DNA in the cell envelope, and maintaining the integrity of the cellular membrane. However, how UV radiation changes the surface properties and thus affects bacterial adhesion remain elusive. In this study, single‐cell force spectroscopy is employed to examine the surface nanomechanics of Pseudomonas aeruginosa under UV exposure. It shows that P. aeruginosa became stiffer after UV radiation, and its adhesion to silicon surface decreases with rupture length increasing. Nanospring signatures in the retraction force curve become less with lower spring constant but more plateau signatures with higher rupture length appear. These facts indicate the unfolding of the α‐helices of the pili. Besides, the worm‐like chain force curves with higher contour length indicate the structural degradation of transmembrane proteins or surface macromolecules obstruction. Accordingly, the bacterial adhesion decreases after UV radiation. [ABSTRACT FROM AUTHOR]