UV-B Radiation Research Articles

Environmental Factors Related to Climate Change Alter the Chemical Composition and Biological Activity of Lavandula viridis L’Hér Essential Oil

Climate change is affecting all regions of the world, and the Mediterranean region is one of the most affected. Plants accumulate secondary metabolites as an adaptive response to stress circumstances. The present study investigated the effect of different abiotic factor conditions (drought, moderate heat, severe heat, salinity, and UV-B radiation) on the essential oil (EO) yield, composition (volatile profile), and biological activity (enzyme inhibition and antioxidant activity) of Lavandula viridis L’Hér. In general, the environmental conditions increased the extraction yield of EO. Eighty-two compounds were identified in the EO and environmental factors induced some quantitative changes in EO composition. Severe heat and salinity conditions increased the concentration of the two most abundant compounds, 1,8-cineole and camphor. Severe heat also increased the potential of EO to inhibit the enzymes butyrylcholinesterase and tyrosinase. Drought, salinity, and UV-B radiation promoted the ability of EO to inhibit acetylcholinesterase. In addition, heat and drought enhanced the antioxidant activity of EO. These results are relevant for exploring the potential of this EO for industrial applications, although future studies combining the factors studied are important to understand the influence of synergistic effects on the composition and bioactivity of the plant products obtained.

Theoretical and Experimental Evaluation of the Electronic Relaxation Mechanisms of 2‐Pyrimidinone: The Primary UVA Absorbing Moiety of the DNA and RNA (6‐4) Photolesion

The (6‐4) photolesion is a key photodamage that occurs when two adjacent pyrimidine bases in a DNA strand bond together. To better understand how the absorption of UVB and UVA radiation by the 2‐pyrimidinone moiety in a (6‐4) lesion can damage DNA, it is important to study the electronic deactivation mechanism of its 2‐pyrimidinone chromophore. This study employs theoretical (MS‐CASPT2/cc‐pVDZ level) and experimental (steady state and femtosecond broadband spectroscopic) methods to elucidate the photochemical relaxation mechanisms of 2‐(1H)‐pyrimidinone and 1‐methyl‐2‐(1H)‐pyrimidinone in aqueous solution (pH 7.4). In short, excitation at 320 nm leads to the population of the S11(pp*) state with excess vibrational energy, which relaxes to the S11(pp*) minimum in one picosecond or less. A trifurcation event in the S11(pp*) minimum ensued, leading to radiative and nonradiative decay of the population to the ground state or the population of the long‐lived and reactive T13(pp*) state in hundreds of picoseconds. Collectively, the theoretical and experimental results the idea that in DNA and RNA, the T13(pp*) state of the 2‐pyrimidinone moiety in the (6‐4) lesion can further participate in photosensitized chemical reactions increasing DNA and RNA damage.

OsUVR8b, rather than OsUVR8a, plays a predominant role in rice UVR8-mediated UV-B response.

UV RESISTANCE LOCUS 8 (UVR8) has been identified in Arabidopsis thaliana as the receptor mediating responses to UV-B radiation. However, UVR8-mediated UV-B signaling pathways in rice, which possesses two proteins (UVR8a and UVR8b) with high identities to AtUVR8, remain largely unknown. Here, UVR8a/b were found to be predominantly expressed in rice leaves and leaf sheaths, while the levels of UVR8b transcript and UVR8b protein were both higher than those of UVR8a. Compared to wild-type (WT) plants, uvr8b and uvr8a uvr8b rice mutants exposed to UV-B showed reduced UV-B-induced growth inhibition and upregulation of CHS and HY5 transcripts alongside UV-B acclimation. However, uvr8a mutant was similar to WT plants and exhibited changes comparable with WT. Overexpressing OsUVR8a/b enhanced UV-B-induced growth inhibition and acclimation to UV-B. UV-B was able to enhance the interaction between E3 ubiquitin ligase OsCOP1 and OsUVR8a/b, whereas the interaction of the homologous protein of Arabidopsis REPRESSOR OF UV-B PHOTOMORPHOGENESIS2 (AtRUP2) in rice with OsUVR8a/b was independent of UV-B. Additionally, OsUVR8a/b proteins were also found in the nucleus and cytoplasm even in the absence of UV-B. The abundance of OsUVR8 monomer showed an invisible change in the leaves of rice seedlings transferred from white light to that supplemented with UV-B, even though UV-B was able to weaken the interactions between OsUVR8a and OsUVR8b homo and heterodimers. Therefore, both OsUVR8a and OsUVR8b, which have different localization and response patterns compared with AtUVR8, function in the response of rice to UV-B radiation, whereas OsUVR8b plays a predominant role in this process.

Photophysical properties and photostability of novel 2-amino-3-benzothiazole thiophene-based azo disperse dyes

The design, synthesis, and use of four new thiophene-based dispersed azo dyes with salicylic and carboxylic acid acceptors are shown in this work. The produced dyes exhibit a wide range of light absorption characteristics, including near UV–visible, and deep red wavelengths. PG9 and PG12, which are thiophene disperse azo dyes with carboxylic acid acceptor, showed red-shifted absorption, but PG10 and PG11, which are azo dyes with salicylic acid, showed blue-shifted absorption. The synthesized dyes exhibited good photostability in solvents. The experimental results are supported by theoretical results from Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT).Furthermore, the dyes exhibit outstanding dyeability with percentage exhaustion characteristics of 90% when applied to acrylic, nylon, and polyester fabrics. Rich shades ranging from deep orange to black are seen in the dyed fabrics. Salicylic acid acceptor-dyed materials have higher K/S values when applied to nylon-dyed fabrics, while acrylic and polyester-dyed fabrics respond better to carboxylic acid acceptor dyes. The fabrics that have been colored display exceptional light, wash, and rubbing fastness. Inlight and wash fastness, polyester-dyed fabrics performed better than acrylic and nylon-dyed fabrics. Studies on UV protection show that fabrics with high UPF ratings canblock damaging UV-A and UV-B radiation efficiently. All synthetic dyes have their antibacterial activity assessed using the AATCC 100 test method, which is associated with the HOMO-LUMO energy gap.

Combination of Nicotinamide and Agastache rugosa Extract: A Potent Strategy for Protecting Hs68 Cells from UVB-Induced Photoaging.

This study investigated the protective effects of nicotinamide (NAM) and Agastache rugosa extract (AR) against ultraviolet B (UVB)-induced photoaging in Hs68 cells. The results demonstrated that NAM and AR, alone or in combination, exhibited concentration-dependent protective effects against UVB radiation. The highest synergistic effect was observed at a NAM:AR ratio of 6:4. This combination exhibited a synergistic protective effect against UVB-induced photoaging. The sample concentration required for 80% cell survival was 9.70 μM and 131.16 ppm for NAM and AR, respectively. However, when combined, they exhibited strong synergistic effects with concentrations as low as 0.11 μM and 17.50 ppm. Moreover, 5.26 μM of NAM and 1,082.13 ppm of AR were required to inhibit 30% of reactive oxygen species, but the combination treatment required 0.62 μM and 95.49 ppm, respectively. This combination significantly reduced the production of matrix metalloproteinase and increased collagen production. These findings highlight the potential of combining NAM and AR as functional cosmetic materials to protect against UVB-induced photoaging. The synergistic effects observed in this study provide valuable information for developing novel strategies for cosmetic combinations that target UVB-mediated skin damage.

Orange Emitting SrS: Eu2+, Dy3+ Afterglow Phosphor: Structural and Luminescence Properties

SrS:Eu is known as an attractive material for imaging, scintillator, or persistent phosphor applications, thanks to its effective photoluminescence (PL) and thermoluminescence (TL) capabilities, but there are still great mysteries of persistent phosphors and attract great interest. Hence, this work investigated the luminescence properties of well-known persistent phosphor based on SrS using various spectroscopic techniques for detailed characterization. Measurements using X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were used to analyze the phase and elements of the phosphor. Belongs to the XRD data the microcrystalline phosphor is cubic, and the diameters ranged from 1 to 100 µm. The morphology of the phosphor was examined by scanning electron microscope (SEM). A time-resolved PL system recorded PL properties, namely the emission and excitation spectra of the phosphor. SrS emits around 626 nm with a broad excitation band peaking around 466 nm. A TLD reader system measured the TL glow curve of the phosphors after UVB radiation. The TL glow curve exhibited a broad peak around 160oC. The dose-response of this peak was obtained up to 600 seconds of exposure to UVB radiation, and it was observed that the dose-response curve exhibits a saturating exponential behavior.

Luminescence under UV(A, B and C) and sunlight exposure of tetrakis Tb3+ carboxylate complexes doped in different polymers

New tetrakis Lanthanide(III) carboxylate-based complexes (Ln3+: Eu and Tb) were successfully synthesized via a facile one-pot method with flufenamic acid (fluf) as ligand and benzimidazole (Bzim) or 1-ethyl-3-methylimidazole (C2mim) as counterions. In addition, the Q[Tb(fluf)4] complexes (Q+: Bzim and C2mim) were doped into polymethylmethacrylate (PMMA), polystyrene (PS), polycaprolactone (PCL) and poly(9-vinylcarbazole) (PVK) polymeric matrices at a 1 % (w/w) concentration and revealed highly desirable photophysical features such as wide range excitation wavelengths for the PMMA and PCL matrices and a very uncommon emission under sunlight exposure arising from the Tb3+ ion for the PMMA material. Thus, the tetrakis compounds with general formula Q[Ln(fluf)4] were characterized by elemental and thermal analysis, ESI-MS mass spectrometry, and FTIR absorption spectroscopy. The PMMA:(1 %)Q[Tb(fluf)4] doped films revealed higher thermal stability than the complexes. The tetrakis Eu3+ complex with Bzim as counterion shows no luminescence either for room or low temperature due to a highly operative low-lying ligand to metal charge transfer (LMCT) state quenching, while the corresponding C2mim-based analogous complex reveals some weak intensity emission, showing very low intrinsic quantum yield (QEuEu) values. On the other hand, the corresponding Tb3+ compounds presented bright green emission for the solid-state complexes and, particularly, for the PMMA:(1 %)Q[Tb(fluf)4] doped films when excited at UVA, UVB, and UVC radiation. Moreover, when the doped PMMA films are exposed to sunlight radiation in an open external environment, a bright green emission arising from the 5D4 → 7F5 transition from the Tb3+ ion can be seen. In this way, these optical results suggest that the PMMA:(1 %)Q[Tb(fluf)4] luminescent photonic materials can act as versatile and efficient light-converting molecular devices (LCMDs).

The Role of Vitamin A on the Histology of Skin of Adult Rats After Eposure to UVB

Background: long-term eposure of skin to sun (UV light) may produce different dermatological changes. The aim of this eperiment is to eplore the protective effects of oral vitamin A on skin subjected to UVB. Methods: twenty rats were separated into: group 1 (without UVB eposure), group 2 (eposed to single daily increasing dose of UVB for one week), group 3 (eposed to UVB with oral daily administration of vit A 10000 IU for one week), group 4 (received vit A for one week). The daily doses of UVB were respectively 0.24, 0.36, 0.48, 0.6, 0.72, 0.84 and 0.96 J/cm2. Skin samples were stained with hematoylin-eosin and Masson’s trichrome stains, in addition to Melan-A stain for melanocytes. Results: histopathological results in skin of group 2 demonstrated loss of normal architecture with increase in thickness of epidermis, hyperkeratosis and parakeratosis, moreover, skin sections detected increased number of inflammatory cells with damaged hair follicles. The basal layer shows an increase in mitotic division and necrosis, besides, epidermal edema and vascular congestion. Furthermore, collagen fibers were degraded. Immunohistochemical reaction revealed intense positive epression of Melan-A with increased proliferation and activity of melanocytes, while sections of groups 1 and 4 show normal healthy skin and negative Melan-A epression. In contrast, skin of group 3 reveals mild hyperkeratosis with normal keratin layer, in addition, the infiltration of inflammatory cells was dropped and hair follicles were preserved. Collagen bundles were slightly degraded with normal arrangement. Immunohistochemical results of this group show mild positive epression of Melan A. Conclusion: oral administration of vitamin A decreases the toic effect of UVB radiation on skin and reduces its induced pigmentation.

Effect of UV-B radiation on photosynthesis based flavonoid synthesis in daylily leaves

In order to assess the impact of UV-B radiation on flavonoid compound levels in 'Stella de Oro' daylily leaves, three distinct treatment groups were established: a control group (CK) devoid of UV-B exposure, a low-dose UV-B group (L, 10 μw/cm²), and a high-dose UV-B group (H, 20 μw/cm²). Throughout the UV-B exposure period, parameters including leaf gas exchange, dry weight ratio, and flavonoid compound content were monitored. Following the UV-B treatment, there was a notable increase in the net photosynthesis rate (Pn) by 72 %, stomatal conductance (Gs) by 46 %, transpiration rate (Tr) by 42 %, and water use efficiency (WUE) by 21 %. Moreover, there was a notable increase in the total content of rutin, myricetin, and quercetin in the leaves by 110 %, 55 %, and 47 % respectively. The observed changes in leaf dry weight ratio under UV-B exposure in group H were consistent with the alterations in flavonoid compound levels in the leaves. Based on the results, PCA analysis indicated a significant correlation between WUE and flavonoids content, possibly related with the combined effect of Pn and Tr.

Topical diosmetin attenuates nociception and inflammation in a ultraviolet B radiation-induced sunburn model in mice.

Burns are a global health problem and can be caused by several factors, including ultraviolet (UV) radiation. Exposure to UVB radiation can cause sunburn and a consequent inflammatory response characterised by pain, oedema, inflammatory cell infiltration, and erythema. Pharmacological treatments available to treat burns and the pain caused by them include nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, antimicrobials and glucocorticoids, which are associated with adverse effects. Therefore, the search for new therapeutic alternatives is needed. Diosmetin, an aglycone of the flavonoid diosmin, has antinociceptive, antioxidant and anti-inflammatory properties. Thus, we evaluated the antinociceptive and anti-inflammatory effects of topical diosmetin (0.01, 0.1 and 1%) in a UVB radiation-induced sunburn model in mice. The right hind paw of the anaesthetised mice was exposed only once to UVB radiation (0.75J/cm2) and immediately treated with diosmetin once a day for 5days. The diosmetin antinociceptive effect was evaluated by mechanical allodynia and pain affective-motivational behaviour, while its anti-inflammatory activity was assessed by measuring paw oedema and polymorphonuclear cell infiltration. Mice exposed to UVB radiation presented mechanical allodynia, increased pain affective-motivational behaviour, paw oedema and polymorphonuclear cell infiltration into the paw tissue. Topical Pemulen® TR2 1% diosmetin reduced the mechanical allodynia, the pain affective-motivational behaviour, the paw oedema and the number of polymorphonuclear cells in the mice's paw tissue similar to that presented by Pemulen® TR2 0.1% dexamethasone. These findings indicate that diosmetin has therapeutic potential and may be a promising strategy for treating patients experiencing inflammatory pain, especially those associated with sunburn.

UV-B Radiation Enhances Epimedium brevicornu Maxim. Quality by Improving the Leaf Structure and Increasing the Icaritin Content.

Epimedium brevicornu Maxim. is a herbal plant with various therapeutic effects, and its aboveground tissues contain flavonol compounds such as icaritin that can be used to produce new drugs for the treatment of advanced liver cancer. Previous studies have shown that ultraviolet-B (UV-B, 280-315 nm) stress can increase the levels of flavonoid substances in plants. In the current study, we observed the microstructure of E. brevicornu leaves after 0, 5, 10, 15, and 20 d of UV-B radiation (60 μw·cm-2) and quality formation mechanism of E. brevicornu leaves after 0, 10, and 20 d of UV-B radiation by LC‒ESI‒MS/MS. The contents of flavonols such as icariside I, wushanicaritin, icaritin, and kumatakenin were significantly upregulated after 10 d of radiation. The results indicated that UV-B radiation for 10 d inhibited the morphological development of E. brevicornu but increased the content of active medicinal components, providing a positive strategy for epimedium quality improvement.

Biodosimetry of UV radiation through the detection of cytogenetic endpoints in Allium cepa meristems

In this study, we examined the response of Allium cepa sprout stem cells, or meristems, to UVB and UVC radiation. The choice of Allium cepa, or onion, was made to avoid the controversial use of animal models. Allium cepa is a well-established in vivo standard model that is frequently used in cytogenetic research connected to various environmental contaminants. Indicators such as micronuclei and chromosomal abnormalities were used to evaluate the genotoxicity of UVB and UVC radiation, and the mitotic index was used to investigate the cytotoxicity of the radiation, providing information on cellular proliferation. The Shapiro-Wilk test (p < 0.05) confirmed the normality of the data. The analysis of the Pearson linear correlation coefficient (r = 0.97), conducted across all dose points considered, including the negative control, revealed an almost perfect positive linear relationship between the dose and the number of cells with micronuclei, for both UVB and UVC. The frequency of induction of micronuclei as a function of dose for both radiation types was found to be similar. However, a difference in the morphology of the cells exposed to UVB radiation compared to those exposed to UVC radiation was observed. In conclusion, the mitotic index analysis showed no significant differences in cell activity between UVC and UVB irradiation compared with control samples. The results from this study support the use of Allium cepa and cytogenetic endpoints as a biodosimetric method for ultraviolet radiation.

Multifunctional and edible egg white/amylose-tannin bilayer film for perishable fruit preservation

The substantial waste of perishable foods during transportation significantly contributes to greenhouse gas emissions, intensifying the climate crisis. To mitigate the rapid spoilage of fruits, an eco-friendly bilayer film was developed using natural egg white (EW), amylose (Am), and tannic acid (TA). The EW/Am-TA bilayer film features a primary layer of amphiphilic EW, ensuring a uniform coating on hydrophobic fruit surfaces, and a secondary layer composed of Am and TA, imparting notable tensile strength (5.3 ± 0.5 MPa) and elongation at break (28.5 ± 4.1 %). This bilayer film effectively shields fruits from UV-B and UV-C radiation (~0 % transmittance at 280 and 330 nm) and exhibits antioxidant and antibacterial properties due to the presence of TA. Fruits such as bananas, avocados, and cherry tomatoes, when dip-coated with the optimized EW/Am-TA bilayer, maintained their freshness, color, weight, and texture for up to seven days, demonstrating the effectiveness of this bilayer coating in food preservation. The natural materials in the coated film are edible and can be safely removed with tap water at room temperature in <10 s, posing no food safety risks. Thus, the proposed bilayer coating presents a significant solution to the global problem of food waste.

A synchronized, large-scale field experiment using Arabidopsis thaliana reveals the significance of the UV-B photoreceptor UVR8 under natural conditions.

This study determines the functional role of the plant ultraviolet-B radiation (UV-B) photoreceptor, UV RESISTANCE LOCUS 8 (UVR8) under natural conditions using a large-scale 'synchronized-genetic-perturbation-field-experiment'. Laboratory experiments have demonstrated a role for UVR8 in UV-B responses but do not reflect the complexity of outdoor conditions where 'genotype × environment' interactions can mask laboratory-observed responses. Arabidopsis thaliana knockout mutant, uvr8-7, and the corresponding Wassilewskija wild type, were sown outdoors on the same date at 21 locations across Europe, ranging from 39°N to 67°N latitude. Growth and climatic data were monitored until bolting. At the onset of bolting, rosette size, dry weight, and phenolics and glucosinolates were quantified. The uvr8-7 mutant developed a larger rosette and contained less kaempferol glycosides, quercetin glycosides and hydroxycinnamic acid derivatives than the wild type across all locations, demonstrating a role for UVR8 under field conditions. UV effects on rosette size and kaempferol glycoside content were UVR8 dependent, but independent of latitude. In contrast, differences between wild type and uvr8-7 in total quercetin glycosides, and the quercetin-to-kaempferol ratio decreased with increasing latitude, that is, a more variable UV response. Thus, the large-scale synchronized approach applied demonstrates a location-dependent functional role of UVR8 under natural conditions.

Contrasting light capture strategies between shade-tolerant and -intolerant tree seedlings responding to solar canopy spectral composition

Forest regeneration is a crucial ecological process for promote self-reproduction and restoration, which is essential for maintaining complex community structure and preserving biological resources. Although sunlight have been considered as the main driver of forest regeneration, how light quality shapes functional traits of seedlings is poorly understood in the forest understorey, where spectral compositions of solar radiation change dramatically. We investigated the responses of 15 typical functional traits of Pinus koraiensis and Quercus mongolica to five filter treatments that differed in the spectral transmittance: (a) 95 % of solar radiation was transmitted (280–700 nm); (b) ultraviolet (UV)-B radiation was attenuated (>315 nm); (c) all UV radiation was attenuated (>400 nm); (d) all UV radiation and blue light was attenuated (>500 nm); (e) all UV radiation, blue-green light was attenuated (>580 nm). Our results showed that functional traits responded to UV-B radiation (contrasting treatment [a] vs. [b]) with species-dependence, but consistently showed a positive response to blue light (contrasting treatment [c] vs. [d]). UV-B radiation decreased the relative growth rate (RGR) and leaf area ratio (LAR) of P. koraiensis seedlings by 48 % and 42 %, respectively; however, it increased seedling height, total leaf area (TLA), and above-ground biomass of Q. mongolica. Blue light consistently increased LAR and RGR of two species. Furthermore, Q. mongolica was more plastic in morphological traits (including plant height and TLA) and root/shoot ratio than P. koraiensis to the single spectral region (UV-B, UV-A, blue, and green light), but opposite in physiological and biochemical traits (such as chlorophyll and anthocyanidin). These suggest that two studied species have evolved different light capture strategies in the understorey: Q. mongolica seedlings tended to adjust morphology and biomass allocation to enhance light interception capacity, while P. koraiensis seedlings preferred to adjust physiological and biochemical traits to enhance light utilization efficiency. A better understanding how canopy spectral compositions affect seedling regeneration may provide a new insight for future forest management (i.e. the appropriate gap creation or tree species combination).

Annexin A1 protects epidermal stem cells against ultraviolet-B irradiation-induced mitochondrial dysfunction.

Ultraviolet-B (UV-B) radiation overexposure causes function impairment of epidermal stem cells (ESCs). We explored the mechanism of Annexin A1 (ANXA1) ameliorating UV-B-induced ESC mitochondrial dysfunction/cell injury. ESCs were cultured in vitro and irradiated with different doses of UV-B. Cell viability/ANXA1 protein level were assessed. After oe-ANXA1 transfection, ESCs were treated with oe-ANXA1/UV-B irradiation/CCCP/CCG-1423/3-methyladenine for 12h. Cell viability/death, and adenosine triphosphate (ATP)/reactive oxygen species (ROS) levels were determined. Mitochondrial membrane potential (MMP) changes/DNA (mtDNA) content/oxygen consumption and RhoA activation were assessed. ROCK1/p-MYPT1/MYPT1/(LC3BII/I)/Beclin-1/p62 protein levels were determined. Mitochondrial morphology was observed. Mito-Tracker Green (MTG) and LC3B levels were determined. UV-B irradiation decreased cell viability/ANXA1 expression in a dose-dependent manner. UV-B-treated ESCs exhibited reduced cell viability/ATP content/MMP level/mitochondrial respiratory control ratio/mtDNA number/RhoA activity/MYPT1 phosphorylation/MTG+LC3B+ cells/(LC3BII/I) and Beclin-1 proteins, increased cell death/ROS/p62/IL-1β/IL-6/TNF-α expression, contracted mitochondrial, disappeared mitochondrial cristae, and increased vacuolar mitochondria, which were averted by ANXA1 overexpression, suggesting that UV-B induced ESC mitochondrial dysfunction/cell injury/inflammation by repressing mitophagy, but ANXA1 promoted mitophagy by activating the RhoA/ROCK1 pathway, thus repressing UV-B's effects. Mitophagy activation ameliorated UV-B-caused ESC mitochondrial dysfunction/cell injury/inflammation. Mitophagy inhibition partly diminished ANXA1-ameliorated UV-B's effects. Conjointly, ANXA1 promoted mitophagy by activating the RhoA/ROCK1 pathway, thereby improving UV-B-induced ESC mitochondrial dysfunction/cell injury.

Phenotypic and genotypic characterization of fifty strains of Beauveria spp. (Ascomycota, Cordycipitaceae) fungal entomopathogens from diverse geographic origins against the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae).

The diamondback moth (DBM) (Plutella xylostella) causes large losses to global crop production. Conventional insecticides are losing effectiveness due to resistance. Consequently, there is a growing interest in sustainable control methods like entomopathogenic fungi (EPF) in Integrated Pest Management. However, the field efficacy of fungi varies due to environmental influences. In this study, a group of 50 Beauveria strains sourced from different locations were characterized by genotype and phenotype with respect to their conidial production, temperature and UV-B radiation tolerance, and virulence against DBM. Phylogenetic analysis revealed two distinct species: Beauveria bassiana (84%) and B. pseudobassiana (16%). Most strains showed optimal growth between 25 °C and 28 °C, with germination severely affected at 10 °C and 33 °C. Notably, 44% displayed high resistance to UV-B radiation (5.94 kJ m-2), with germination rates between 60.9% and 88.1%. Geographical origin showed no correlation with temperature or UV radiation tolerance. In virulence experiments, 52% of strains caused mortality rates exceeding 80% in DBM second instars at 7 days after exposure to a 4 mL conidial suspension (107 conidia/mL). Survival under environmental conditions is crucial for EPF-based commercial products against DBM. Results suggest strain tolerance to environmental stressors is more tied to specific micro-climatic factors than geographical origin. Each strain exhibited unique characteristics; for example, the most virulent strain (#29) was highly UV-sensitive. Therefore, characterizing diverse strains provides essential genotypic and phenotypic insights, which are fundamental for understanding their role as biocontrol agents while facilitating efficient biopesticide product development and uptake. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

DETERMINING THE ATTITUDES OF THE PEOPLE WHO COME TO THE OPTICAL STORE IN ESKISEHIR TOWARD THE USE OF SUNGLASSES

Exposure to ultraviolet (UV) rays of the sun can cause important health problems such as skin cancer, cataracts, eye problems, and suppression of the immune system. UV accumulated in our eyes throughout our lives can cause irreversible damage. Sunglasses are the most important tool in protecting our eyes from UV and helping us see. Good sunglasses should absorb UVA and UVB radiation, preventing eye damage. Statistical analysis of 311 participants in an optical store, the UV protection of sunglasses, the reflection of UV rays on the surface, the harms of imitation glasses, the lens color preferred by the users, the reasons for using sunglasses, the frequency of use of the users were made with the SPSS program. Determining people's knowledge level about sunglasses use and sharing the results will reduce the financial cost to the country and reduce cataract formation, making a significant contribution to the literature.

Ultraviolet Resistance of Microorganisms Isolated from Uranium-Rich Minerals from Perus, Brazil.

The district of Perus, located in the city of São Paulo, Brazil, is renowned for its weathered granitic-pegmatitic masses, which harbor a significant number of uraniferous minerals that contribute to ionizing radiation levels up to 20 times higher than the background levels. In this study, aseptically collected mineral samples from the area were utilized to isolate 15 microorganisms, which were subjected to pre-screening tests involving UV-C and UV-B radiation. The microorganisms that exhibited the highest resistance to ultraviolet (UV) radiation were selected for the construction of survival curves for UV-C, broad-band UV-B, and solar simulation resistance testing. Subsequently, the four strains that demonstrated superior survival capabilities under UV radiation exposure were chosen for 16S rRNA gene sequencing. Among these, Nocardioides sp. O4R and Nocardioides sp. MA2R demonstrated the most promising outcomes in the UV radiation resistance assessments, showcasing comparable performance to the well-established radioresistant model organism Deinococcus radiodurans. These findings underscore the potential of naturally occurring high-radiation environments as valuable resources for the investigation of UV-resistant microorganisms. Astrobiology 24, 783-794.

Comprehensive studies reveal physiological and genetic diversity in traditional rice cultivars for UV-B sensitivity

Acclimation to crop niches for thousands of years has made indigenous rice cultivars better suited for stress-prone environments. Still, their response to UV-B resiliency is unknown. 38 rice landraces were grown in cemented pots in a randomised block design with three replicates under open field conditions in Sambalpur University in the wet season of 2022. Half of the plants in each of the cultivars were administered UV-B radiation at the panicle emergence stage in an adjustable UV-B chamber permitting sunlight, and the effects of the stress on various morpho-physiological features, such as spikelet sterility, flag leaf photosynthetic and flavonoid pigment contents, and lipid peroxidation activities, were estimated for calibration of stress resistance. The experiment identified Swarnaprabha and Lalkain as the most sensitive and resilient to stress respectively, and the differential response between them was further revealed in the expression of genes related to UV-B sensitivity. Subject to the stress, Swarnaprabha exhibited symptoms of injuries, like leaf burns, and a higher loss of various photosynthetic parameters, such as pigment contents, SPAD and Fv/Fm, ETR and qP values, while NPQ increased only in Lalkain. Exposure to UV-B increased the total phenolic and flavonoid contents in Lalkain while depressing them in Swarnaprabha. Such an effect amounted to a higher release of fluorescent energy in the latter. The levels of expression of gene families controlling flavonoid activation and UV-B signal transduction, such as OsWRKY, OsUGT, OsRLCK, OsBZIP, OsGLP, and CPD photolyase were similar in both the cultivars in the control condition. However, exposure to UV-B stress overexpressed them in resilient cultivars only. The magnitude of expression of the genes and the impact of the stress on photosynthetic parameters, phenolic compounds and pubescent hair structure at the panicle emergence stage could be valid indicators among indigenous rice for UV-B tolerance.