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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]

Stomata, the small pores on the surfaces of plant leaves and stems, are crucial for gas exchange and also play a role in defense against pathogens. Stomatal movement is influenced not only by surrounding light conditions but also by the presence of foliar pathogens. Certain light wavelengths such as blue or high irradiance red light cause stomatal opening, making it easier for bacteria to enter through opened stomata and causing disease progression in plants. Illumination with blue or intense red light autophosphorylates phototropin, a blue light photoreceptor protein kinase, that in turn activates a signaling cascade to open the stomata. Undoubtedly stomatal defense is a fascinating aspect of plant immunology, especially in plant–foliar pathogen interactions. During these interactions, stomata fundamentally serve as entry points for intrusive pathogens and initiate the plant defense signaling cascade. This review highlights how light-activated photoreceptors such as cryptochromes (CRYs), phytochromes (phys), and UV-receptors (UVRs) influence stomatal movement and defense signaling after foliar pathogen intrusion. It also explores the link between stomatal defense, light signaling, and plant immunity, which is vital for safeguarding crops against pathogens. [ABSTRACT FROM AUTHOR]

In this study, the effects of UV radiation on the high temperature fatigue performance of SBS modified asphalt and asphalt mixtures were analyzed, and the effects of outdoor atmospheric UV radiation were simulated by indoor UV accelerated aging test. The results showed that the increase of UV radiation time led to the increase of creep recovery rate of asphalt and the decrease of irrecoverable creep flexibility, i.e., the resistance to permanent high temperature deformation of SBS modified asphalt was improved. The fatigue cracking resistance of asphalt was weakened and accelerated by radiation. UV radiation increased the rutting resistance of asphalt mixtures and weakened the fatigue resistance at high temperatures. At the same time, UV radiation reduced the aromatic and saturated content of SBS modified asphalt, which led to a reduction in the relative aromatic and saturated content of asphalt mixtures. [ABSTRACT FROM AUTHOR]

Surface modification of various polymer foils was achieved by UV activation and chemical grafting with cysteamine to improve surface properties and antimicrobial efficacy. UVC activation at 254 nm led to changes in surface wettability and charge density, which allowed the introduction of amino and thiol functional groups by cysteamine grafting. X-ray photoelectron spectroscopy (XPS) confirmed increased nitrogen and sulfur content on the modified surfaces. SEM analysis revealed that UV activation and cysteamine grafting resulted in distinct surface roughness and texturing, which are expected to enhance microbial interactions. Antimicrobial tests showed increased resistance to algal growth (inhibition test) and bacterial colonization (drop plate method), with significant improvement observed for polyethylene terephthalate (PET) and polyetheretherketone (PEEK) foils. The important factors influencing the efficacy included UV exposure time and cysteamine concentration, with longer exposure and higher concentrations leading to bacterial reduction of up to 45.7% for Escherichia coli and 55.6% for Staphylococcus epidermidis. These findings highlight the potential of combining UV activation and cysteamine grafting as an effective method for developing polymeric materials with enhanced antimicrobial function, offering applications in industries such as healthcare and packaging. [ABSTRACT FROM AUTHOR]

The degradation of rubber materials under environmental and mechanical stress presents a significant challenge, particularly due to UV (ultraviolet light) exposure, which severely impacts the material's physical properties. This study aims to enhance the UV stability and longevity of rubber by evaluating the performance of modified polyurethane and silicone coatings as protective stabilizers. Natural rubber—styrene–butadiene rubber (NR-SBR), known for its exceptional mechanical properties, was selected as the base material. To ensure strong adhesion, cold atmospheric plasma treatment was applied, increasing the surface energy by 250%, primarily through an enhancement of the polar component. After treatment, supplier-recommended coatings were applied and tested for adhesion using the pull-out method. Aging tests under UV exposure, water immersion, and high temperatures were conducted to assess durability, with tensile tests used to monitor changes over time. Coatings exhibiting cracking after UV exposure were excluded from further analysis. A silicone coating demonstrating superior moisture resistance and durability under extreme conditions was identified as a promising candidate for future UV stabilization applications. These findings provide a foundation for developing advanced coatings to significantly extend the service life of rubber materials in demanding environments. [ABSTRACT FROM AUTHOR]

Background: CELF2 belongs to the CELF RNA‐binding protein family and exhibits antitumor activity in various tumor models. Analysis of the pan‐cancer TCGA database reveals that CELF2 expression strongly correlates with favorable prognosis among cancer patients. The function of CELF2 in nonmelanoma skin cancer has not been studied. Methods: We used shRNA‐mediated knockdown (KD) of CELF2 expression in human squamous cell carcinoma (SCC) cells to investigate how CELF2 impacted SCC cell proliferation, survival, and xenograft tumor growth. We determined CELF2 expression in human SCC tissues and adjacent normal skin using immunofluorescence staining. Additionally, we investigated the changes in CELF2 and its target gene expression during UV‐induced and chemical‐induced skin tumorigenesis by western blotting. Results: CELF2 KD significantly increased SCC cell proliferation, colony growth, and SCC xenograft tumor growth in immunodeficient mice. CELF2 KD in SCC cells led to activation of KRT80 and GDF15, which can potentially promote cell proliferation and tumor growth. While control SCC cells were sensitive to anticancer drugs such as doxorubicin, SCC cells with CELF2 KD became resistant to drug‐induced tumor growth retardation. Finally, we found CELF2 expression diminished during both UV‐ and chemical‐induced skin tumorigenesis in mice, consistent with reduced CELF2 expression in human SCC tumors compared to adjacent normal skin. Conclusion: This study shows for the first time that CELF2 loss occurs during skin tumorigenesis and increases drug resistance in SCC cells, highlighting the possibility of targeting CELF2‐regulated pathways in skin cancer prevention and therapies. [ABSTRACT FROM AUTHOR]

The article discusses the evolutionary innovations in land plants, focusing on the role of flavonoids in responding to environmental stressors. Flavonoids are highlighted for their multifunctionality, including antioxidant properties and regulation of plant growth and development. The text explores the ancient origins of flavonoids and their diverse roles in plant-environment interactions, emphasizing their ability to modulate oxidative stress signaling pathways. The study also delves into the relationship between flavonoids and abiotic stressors, such as UV radiation, and their involvement in signaling pathways related to auxin and ABA. The article concludes by underscoring the importance of antioxidant flavonoids in plant adaptation to changing environmental conditions. [Extracted from the article]

Copyright of Die Ophthalmologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The raising economic importance of cannabis arouses interest in positively influencing the secondary plant constituents through external stimuli. One potential possibility to enhance the secondary metabolite profile is the use of UV light. In this study, the influence of spectral UV quality at different intensity levels on photomorphogenesis, growth, inflorescence yield, and secondary metabolite composition was investigated. Three UV spectra with five different intensities were considered: L1 (UVA:B = 67:33, 4.2 W/m2), L2 (UVA:B = 94:6, 4.99 W/m2), L3_1 (UVA:B = 99:1, 1.81 W/m2), L3_2 (UVA:B = 99:1, 4.12 W/m2) and L3_3 (UVA:B = 99:1, 8.36 W/m2). None of the investigated UV treatments altered the cannabinoid profile. Regarding the terpenes investigated, light variant L3_1 was able to positively influence the terpene profile. Especially linalool (+29%), limonene (+25%) and myrcene (+22%) showed an increase, compared to the control group without UV treatment. Growth and leaf morphology also showed significant changes compared to the control. While a high UVA share increased the leaf area, a higher UVB share led to a smaller leaf area. Of the UV sources examined, only L3_1 with 1.81 W/m2 and a radiation dose of 117.3 kJ m2 d-1 is suitable for practical use in commercial cannabis cultivation. The terpene concentration for this group was in part significantly increased with constant yield and cannabinoid concentration. [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]

Skin melanoma is a potentially fatal form of cancer. If left untreated or allowed to spread, it can lead to death or serious disability. Therefore, early diagnosis is crucial for improving patient prognosis and outcomes. Recent advances in machine learning (ML) and deep learning (DL) have greatly contributed to the categorisation and identification of melanoma. The goal of this survey is to evaluate 60 publications that have been submitted in order to create an overview of the melanoma detection process. It examines several feature extraction techniques.The evaluation concentrates on different melanoma detection methods, including 'deep learning (DL)' and 'machine learning (ML)' models. The analysis includes performance metrics and a review of the results obtained from the PH2 dataset, which achieved a high accuracy of 96.5%. Finally, the survey addresses research gaps to facilitate future investigations into melanoma identification strategies. [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]

Adhesive modification with nanoparticles affects multiple adhesives properties, making it essential to evaluate and compare changes across all key characteristics—existing positive and limiting properties. This study investigates the impact of silica (SiO2) and titanium dioxide (TiO2) nanoparticles on the elasticity and aging resistance of PVAc adhesive. Tensile properties were determined according to ISO 527-3:2018, with Young's moduli of elasticity Ε , and stress–strain curves for neat PVAc, nano-SiO2 PVAc, and nano-TiO2 PVAc adhesive. Material toughness ( U T ), failure stresses σ f , and failure strains ε f were also calculated. After UV exposure (0, 48, and 96 h), according to ISO 9142:2003, samples were characterized by Fourier-transform infrared spectroscopy (FTIR). Analysis of variance (ANOVA) was performed to determine if there is a statistically significant difference in material toughness between neat PVAc and nano-modified PVAc adhesives, as well as changes in FTIR spectra of paper–adhesive samples before and after UV exposure. The Bonferroni post hoc test was used to identify specific group differences. The results showed that SiO2 nanoparticles improved PVAc elasticity by 9.15%, while TiO2 nanoparticles reduced elasticity by 44.47%. FTIR analysis revealed similar behavior in both nano-modified and neat PVAc adhesives after UV exposure, indicating that aging resistance was preserved with the addition of SiO2 or TiO2. [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]

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.

Despite the loss of melanocytes, individuals with vitiligo have a significantly lower risk of developing skin malignancies compared to ethnicity‐matched controls. The study investigated the molecular mechanisms that protect skin cells (keratinocytes) from UV‐B‐induced DNA damage in individuals with vitiligo. The study found that upregulation of stem cell factor (SCF) signaling significantly reduced γ‐H2AX positivity and cyclobutane pyrimidine dimer formation and improved mitochondrial health (elongated mitochondria, reduced reactive oxygen species [ROS] and lipid peroxidation) in keratinocytes upon UV‐B exposure. Interestingly, SCF treatment also reduced lipid droplet accumulation and triacylglyceride levels by upregulating lipoprotein lipase (LPL). Further, siLPL increased DNA damage and lipid droplet (LD) accumulation, while NO‐1886, an LPL agonist, reversed both, suggesting a direct link between lipid metabolism and DNA damage. Downregulation of NAD‐dependent deacetylase sirtuin1 (SIRT1) with siRNA or with Ex‐527, a pharmacological inhibitor of SIRT1, diminished the protective effects mediated by SCF and NO‐1886, suggesting SIRT1 to be the final effector protein in the SCF‐LPL‐SIRT1 signaling axis. Analysis of clinical samples of vitiligo corroborated the upregulation of SCF and LPL in lesional epidermis. In conclusion, our study demonstrates a novel SCF‐LPL‐SIRT1 signaling axis that confers protection to vitiligo keratinocytes from the harmful effects of UV‐B radiation. [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]

Overexposure to blue light due to the excessive use of electronic devices has been implicated in premature skin aging and eye damage, among other injuries to health. This study aimed to synthesize two azo derivatives of the 2‐(amino‐2′‐hydroxyphenyl) benzoxazole and explore their potential as UV and blue light filters, proposing a new spectral profile. The synthesis of the heterocyclic compounds involved condensation reactions and diazotation. The derivatives 2‐(benzoxazol‐2‐yl)‐5‐[(2‐hydroxynaphthyl)diazenyl]phenol and 2‐(benzoxazol‐2‐yl)‐4‐[(2‐hydroxynaphthyl)diazenyl]phenol were synthesized with a yield greater than 70%. Solubility was evaluated in seven different solvents. The maximum absorption wavelengths (λmax) were determined using UV–Vis scanning spectrophotometry in the range of 200–600 nm. Photostability was assessed using a solar simulator and the Sun protection factor (SPF) was determined using in vitro methodology. Cytotoxicity was evaluated using the MTT assay in V79 cells. These compounds were able to absorb UVA, UVB, and blue light, with λmax ranging from 300 to 500 nm and demonstrated photostability after 3 h of exposure to solar simulator with an SPF higher than 45. The compounds exhibited solubility in all lipophilic solvents tested. Regarding cytotoxicity, IC50 values were comparable to other filters. These findings indicate that both compounds hold promise as potential organic filters. [ABSTRACT FROM AUTHOR]

Nucleic acids, lipids, and other cell components can be found within different types of extracellular vesicles (EVs), which include apoptotic bodies (ABs), large extracellular vesicles (LEVs), and small extracellular vesicles (SEVs). Release of LEVs from cells can be reduced by genetic or pharmacological inhibition of the enzyme acid sphinogomyelinase (aSMase), and indeed several studies have demonstrated a role for the clinically approved aSMase inhibitor imipramine in blocking LEV release, including in response to UVB exposure. Given that exposure of keratinocytes to UVB radiation results in the generation of UVR photoproducts in DNA that can subsequently be found in association with ABs and SEVs, we examined how imipramine impacts the release of extracellular DNA containing UVR photoproducts at an early time point after UVR exposure. Using several different model systems, including cultured keratinocytes in vitro, discarded human surgical skin ex vivo, and skin biopsies obtained from treated human subjects, these pilot studies suggest that imipramine treatment stimulates the release of CPD‐containing, SEV‐associated DNA. These surprising findings indicate that LEV and SEV generation pathways could be linked in UVB‐irradiated cells and that imipramine may exacerbate the systemic effects of extracellular UVR‐damaged DNA throughout the body. [ABSTRACT FROM AUTHOR]

The nucleotide excision repair (NER) system removes UV photoproducts from genomic DNA and is controlled by the circadian clock. Given that small‐molecule compounds have been developed to target various clock proteins, we examined whether the cryptochrome inhibitor KS15 and REV‐ERB antagonist SR8278 could modulate keratinocyte responses to UV radiation in vitro. We observed that though SR8278 promoted cell viability in UVB‐irradiated cells, it had little effect on NER or on the expression of the clock‐regulated NER factor XPA. Rather, we found that both KS15 and SR8278 absorb light within the UV spectrum to limit initial UV photoproduct formation in DNA. Moreover, SR8278 promoted UVB viability even in cells in which the core circadian clock protein BMAL1 was disrupted, which indicates that SR8278 is likely acting via other REV‐ERB transcriptional targets. We further observed that SR8278 sensitized keratinocytes to light sources containing primarily UVA wavelengths of light likely due to the generation of toxic reactive oxygen species. Though other studies have demonstrated beneficial effects of SR8278 in other model systems, our results here suggest that SR8278 has limited utility for UV photoprotection in the skin and will likely cause phototoxicity in humans or mammals exposed to solar radiation. [ABSTRACT FROM AUTHOR]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main purpose of this study was to create a prototype of an unmanned aerial system equipped with intelligent hardware and software technologies necessary for surveillance and monitoring the health and growth of crops from orchards with vines and fruit trees. Using low-cost sensors that accurately measure ultraviolet solar radiation was an important objective. The device, which needed to be attached to the commercial DJI Mini 4 Pro drone, had to be small, portable, and have low energy consumption. For this purpose, the widely used Vishay VEML6075 digital optical sensor was selected and implemented in a prototype, alongside a Raspberry Pi Zero 2 W minicomputer. To collect data from these sensors, a program written in Python was used, containing specific blocks for data acquisition from each sensor, to facilitate the monitoring of ultraviolet (UV) radiation, or battery current. By analyzing the data obtained from the sensors, several important conclusions were drawn that may provide valuable pathways for the further development of mobile or modular equipment. Furthermore, the plantation state analysis results with proposed models in the geographic information system (GIS) environment are also presented. The visualization of maps indicating variations in vegetation conditions led to identifying problems such as hydric stress. [ABSTRACT FROM AUTHOR]

Ultraviolet solar radiation at the Earth's surface significantly impacts both human health and ecosystems. A biologically effective daily radiant exposure (BEDRE) model is proposed for various biological processes with an analytical formula for its action spectrum. The following processes are considered: erythema formation, previtamin D3 synthesis, psoriasis clearance, and inactivation of SARS-CoV-2 virions. The BEDRE model is constructed by multiplying the synthetic BEDRE value under cloudless conditions by a cloud modification factor (CMF) parameterizing the attenuation of radiation via clouds. The CMF is an empirical function of the solar zenith angle (SZA) at midday and the daily clearness index from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) measurements on board the second-generation Meteosat satellites. Total column ozone, from MERRA-2 reanalysis, is used in calculations of clear-sky BEDRE values. The proposed model was trained and validated using data from several European ground-based spectrophotometers and biometers for the periods 2014–2023 and 2004–2013, respectively. The model provides reliable estimates of BEDRE for all biological processes considered. Under snow-free conditions and SZA < 45° at midday, bias and standard deviation of observation-model differences are approximately ±5% and 15%, respectively. The BEDRE model can be used as an initial validation tool for ground-based UV data. [ABSTRACT FROM AUTHOR]

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]

Caenorhabditis elegans (C. elegans) has emerged as an outstanding model organism for investigating the aging process due to its shortened lifespan, well-defined genome, and accessibility of potent genetic tools. This review presents the current findings on chronological aging and photoaging in C. elegans, exploring the elaborate molecular pathways that control these processes. The progression of chronological aging is characterized by a gradual deterioration of physiological functions and is influenced by an interaction of genetic and environmental factors, including the insulin/insulin-like signaling (IIS) pathway. In contrast, photoaging is characterized by increased oxidative stress, DNA damage, and activation of stress response pathways induced by UV exposure. Although the genetic mechanisms of chronological aging in C. elegans have been characterized by extensive research, the pathways regulating photoaging are comparatively less well-studied. Here, we provide an overview of the current understanding of aging research, including the crucial genes and genetic pathways involved in the aging and photoaging processes of C. elegans. Understanding the complex interactions between these factors will provide invaluable insights into the molecular mechanisms underlying chronological aging and photoaging and may lead to novel therapeutic approaches and further studies for promoting healthy aging in humans. [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]

Many bodies of water around the world are eutrophic and present cyanobacterial blooms. Oxidation techniques with ozone and UV radiation have been shown to be effective in laboratory conditions with controlled cultures, but studies with eutrophicated natural waters (non-laboratory conditions) are still lacking. Therefore, the main objective of the present work was to develop a mathematical model to determine the doses of different oxidizing agents [ozone (O3), ultraviolet (UV) radiation at 254 nm and ozone-based advanced oxidation] to eliminate three photosynthetic organisms [Microcystis aeruginosa (MC), Anabaena (ANA) and Actinastrum] from a eutrophicated artificial lagoon. To this end, 24 physicochemical and biological water quality parameters were measured. Different equations were proposed to calculate the demand of the oxidizing agents to reduce the concentration of organisms to low risk levels, even in the presence of other pollutants. O3 presented the best results by eliminating 100 and 88% of MC and ANA at a dose of 15 mg O3/L. From the principal component analysis, it is observed that the main factor related to the reduction of turbidity was the destruction of the cells. Furthermore, this statistical analysis shows that the application of these oxidants produces an oxidation-release cycle of organic components because of cell lysis. This article presents for the first time a mathematical model that allows knowing the appropriate doses of different oxidants to eliminate this type of organisms in eutrophic waters, i.e., even in the presence of other types of ozone-consuming pollutants. [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]

UV radiation causes long- and short-term skin damage, such as erythema and skin cancer. Therefore, the use of sunscreens is extremely important. However, concerns about UV filter safety have prompted exploration into alternative solutions, with nanotechnology emerging as a promising avenue. This systematic review identified 23 experimental studies utilizing nanocarriers to encapsulate sunscreens with the aim of enhancing their efficacy and safety. Polymeric and lipid nanoparticles are frequently employed to encapsulate both organic and inorganic UV filters along with natural antioxidants. Nanocarriers have demonstrated benefits including reduced active ingredient usage, increased sun protection factor, and mitigated photoinstability. Notably, they also decreased the skin absorption of UV filters. In summary, nanocarriers represent a viable strategy for improving sunscreen formulations, offering enhanced physicochemical properties and bolstered photoprotective effects, thereby addressing concerns regarding UV filter safety and efficacy in cosmetic applications. [ABSTRACT FROM AUTHOR]