Search Results (512)

Broiler chickens are commonly reared in closed housing systems with limited exposure to sunlight, thereby relying entirely on dietary sources of vitamin D. The hydroxylated metabolite 25-hydroxycholecalciferol [25(OH)D₃] has been proposed as a more potent form than native vitamin D₃ (cholecalciferol). This study evaluated the effects of dietary supplementation with vitamin D₃ alone or in combination with 25(OH)D₃ on growth performance, bone characteristics, and cecal microbiota in Ross 308 broilers. A total of 952 one-day-old male chicks were allocated to four treatments: a negative control (no vitamin D₃), a positive control (vitamin D₃ according to Ross 308 specifications), and a positive control supplemented with 25(OH)D₃ at 1394 or 2788 IU/kg, in a randomized design with 17 replicates per treatment and 14 birds per replicate. Over a 40-day feeding trial, diets containing vitamin D₃ (positive control) or supplemented with 25(OH)D₃ significantly improved final body weight, weight gain, average daily gain, and feed conversion ratio compared with the negative control (p < 0.01), with no significant differences among the positive control and 25(OH)D₃-supplemented groups, with a clear linear dose-dependent response. Although tibia ash and bone-breaking strength were not significantly affected, linear responses indicated a slight numerical trend toward improved skeletal mineralization with increasing 25(OH)D₃. Microbiota analysis indicated that 25(OH)D₃ affected cecal microbial ecology: low-dose inclusion showed reduced species richness and evenness, whereas high-dose inclusion restored richness to levels comparable to the positive control and enriched taxa associated with fiber fermentation and bile acid metabolism while reducing Lactobacillus dominance. In conclusion, supplementation with 25(OH)D₃ in addition to vitamin D₃ enhanced growth performance and selectively shaped the cecal microbiota of broilers, with suggestive benefits for bone mineralization. These findings highlight 25(OH)D₃ as a more potent source of vitamin D than cholecalciferol alone and support its practical use in modern broiler nutrition to improve efficiency, skeletal health, and microbial balance. Full article

Severe depression is shaped by complex interactions between public health crises and socioeconomic conditions, yet the spatial and temporal dynamics of these factors remain underexplored. This study investigates the impact of COVID-19 case rates, vaccination rates, and socioeconomic factors on severe depression rates across 1470 counties in the contiguous USA in 2021 and 2022. We combined Ordinary Least Squares (OLS) regression with Multiscale Geographically Weighted Regression (MGWR) to capture both global associations and local geographic variability. Results show that higher COVID-19 case rates in 2021 were associated with increased rates of severe depression in 2022, while higher vaccination rates during the same period were associated with decreased rates of severe depression. However, these associations weakened when using 2022 data, suggesting a temporal lag in the impact on mental health. MGWR analyses revealed regional disparities: COVID-19 case rates had a stronger impact in the Midwest, while vaccination benefits were more pronounced on the West Coast. Additional factors, such as unemployment, limited sunlight exposure, and the availability of mental health resources, also influenced outcomes. These findings underscore the importance of temporally and geographically nuanced approaches to public mental health interventions and support the need for region-specific strategies to address mental health disparities in the wake of public health crises. Full article

Exposure to sunlight, whose main component is UV radiation (UVR), leads to various skin damage such as sunburns, premature aging, or more severe issues such as increased symptoms of autoimmune disease and skin cancer. Therefore, there is a growing interest in developing improved photoprotective agents that can protect skin from sunlight incidence and antioxidants that counteract the oxidative stress caused by it. Lichens are a source of such agents since they adapt to extreme environments including those with high UVR by biosynthesizing metabolites with those properties. In this study, brialmontin 2 (1), physciosporin (2), and pseudocyphellarin A (3) were isolated for the first time from the lichen Pseudocyphellaria berberina (G. Forst.) D. J. Galloway & P. James, along with calycin (4) and 22-hydroxystictan-3-one (5). Their structural characterization was carried out by spectroscopy (¹H and ¹³C NMR). Sun protection factor (SPF) along with critical wavelength (λ_crit), a UVA/UVB ratio (UVA/UVB-r) of one to five, and acetone extract (AE) were evaluated spectrophotometrically as a measure of their UVB and UVA photoprotective capacities, respectively. Additionally, their antioxidant activity was measured by scavenging DPPH free radicals (RSA). Compounds 2, 4, and AE showed “medium” UVB photoprotective capacities (with SPFs between 15 and 30). Additionally, 4 and AE presented “maximum” UVA photoprotective capacities (λ_crit > 370 nm and UVA/UVB-r > 0.8), whereas this activity was “good” for 2 and 3 (λ_crit 350 to 370 nm and UVA/UVB-r 0.4 to 0.6), and “moderate” for 1 (λ_crit 335 to 350 nm and UVA/UVB-r 0.2 to 0.4). All compounds and AE showed antioxidant activity, standing out were AE and 4 with activity comparable to the controls (ca. 95 and 81 RSA %, respectively, at 1000 ppm). AE and 4 are dual agents with photoprotective (UVB-UVA) and antioxidant capacities that could help prevent skin damage associated with sunlight. In silico assays suggest that 4 spontaneously diffuses into the stratum corneum with limited absorption through the skin. Additionally, 4 lacks potential toxicity to Normal Human Epidermal Keratinocytes (showing viability ca. 70% at 100 ppm); therefore, it is a candidate for the development of sunscreen formulations. Full article

Several minerals are known to undergo chromatic variations when exposed to sunlight, particularly ultraviolet (UV) radiation. These phases, defined as photosensitive, exhibit colour change due to photochemical reactions. To understand this phenomenon, this study investigates the colour alteration in 26 common mineral phases, aiming to better understand their behaviour under artificial ageing conditions. Each mineral was firstly chemically characterised by SEM-EDS to identify common chromophoric impurities. Subsequently, samples were exposed to UV radiation in the climatic chamber. The colour shifts were semi-quantitatively assessed in the CIEL*a*b* colour space after ageing. The results indicate that just 4 minerals out of 26 display negligible colour variation, whereas 22 show evident colour changes. These findings highlight the vulnerability of photosensitive minerals to UV-induced colour changes and raise concerns regarding their behaviour in artworks, historical surfaces, and cultural heritage objects. As such minerals are frequently found in the heritage field, understanding their photochemical responses is essential for developing informed preventive conservation strategies, particularly concerning light exposure in both museum and outdoor contexts. Full article

Background: “Long COVID” refers to a condition in which individuals continue to experience persistent signs and symptoms even after recovering from the initial COVID-19 infection. Signs and symptoms that persist can affect multiple organs in the body. Vitamin D is an essential nutrient that plays a crucial role, particularly in the immune system, and may be linked to the development of long COVID. Objective: The study aimed to investigate the association between vitamin D levels and the prevalence of long COVID signs and symptoms in COVID-19 patients. Materials and Methods: The study enrolled 170 COVID-19 patients with mild signs and symptoms and confirmed COVID-Ag or RT-PCR tests. The subjects were aged 18–59 years. All patients had 25(OH)D levels measured within 60 days of COVID-19 diagnosis and had been followed for at least 3 months post-infection. Data collected included demographic characteristics, serum 25(OH)D levels, and self-reported long COVID signs and symptoms questionnaire responses. Results: The study results indicated a female-to-male ratio of 1.1:1 and a mean age of 45.87 ± 8.65 years; of these, 62.4% received three doses of the COVID-19 vaccine, and 64.7% developed long COVID. The most prevalent signs and symptoms were respiratory (55.3%), skin (50.6%), and general (39.4%). The median blood vitamin D level was 22.96 ng/mL, with 41.2% of subjects having insufficient levels, 30.6% having deficient levels, and 28.2% having sufficient levels. Patients with long COVID had significantly lower vitamin D levels compared with those without long COVID (21.52 ng/mL vs. 25.46 ng/mL; p < 0.05). Multivariable analysis found that vitamin D deficiency was significantly associated with overall long COVID signs and symptoms (Adj. OR, 5.80 [95% CI: 2.10, 16.13]). Additionally, vitamin D deficiency significantly increased the number of long COVID systemic signs and symptoms (Adj. IRR, 3.30 [2.12, 5.12]). Conclusion: Assessing and maintaining vitamin D levels, vitamin D supplementation, and sunlight exposure in COVID-19 patients can reduce the risk and severity of long-term COVID-19 signs and symptoms. Full article

Micro- and nanoplastic (MNP) particles are constantly formed through plastic fragmentation by sunlight, friction, or oxidation. MNPs potentialize health risks when entering the human body by ingestion, infusion, inhalation, and skin absorption. Still, the translocation among intracellular compartments must also be considered because MNPs can reach the circulatory system and be found in virtually all body fluids, tissues, and organs, potentially causing significant health impacts. The ability of MNPs to interact with macromolecules and cause damage to intracellular structures results in several physiopathological conditions, such as inflammation, oxidative imbalance, apoptosis, and carcinogenesis. One major challenge in MNP research is the development of reliable detection and quantification methods and effective sample separation processes. Although there is evidence directly linking MNPs to heart disease, the same cannot be said for diseases such as cancer, respiratory conditions, and reproductive system disorders. Therefore, the impact of MNPs on human health was examined, and a careful evaluation of their effects was carried out. We reviewed the extensive scientific literature from the past years, focusing on exposure, aging, interactions, and effects on entering MNPs into human metabolism and the physiological systems, which makes these particles particularly hazardous. Full article

Although the presence of anthocyanins in white asparagus is undesirable because it degrades its commercial quality, very little is known about their biosynthesis and regulation. The biosynthesis of anthocyanins in most plants is light dependent, but in white asparagus spears only a few studies have evaluated the effects of light and all of them focus mainly on the post-harvest period. There are no relevant reports on the effects of exposure of spears to solar and infrared radiation during their growth and development. For this purpose, white asparagus spears were grown in the dark under a low tunnel (100 cm wide and 60 cm high) for 7 days before being exposed to sunlight for 0, 2, 3, 4, 5, or 7 h. Subsequently, the spears were either harvested and kept in the dark or continued to grow in the dark for 0, 24, or 48 h. At the end of the treatments, the color and the anthocyanin and total phenol content of the top 7 cm of the spears were determined. The results showed that the infrared radiation that was trapped below the tunnel during the 7-day growing period of white asparagus spears induced anthocyanin biosynthesis only in the lower part (base) of the spears. Exposure to sunlight for at least 3 h was critical for significant anthocyanin biosynthesis in the epidermal cells of the top 7 cm part of white asparagus spears (0.48–0.95 μg g⁻¹ FW). The amount of anthocyanins 24 h later was proportional to the exposure time (y = 0.1585x − 0.162, R² = 0.9953) and was greater in the spears harvested and kept in the dark (up to 5.67 μg g⁻¹ FW) than in the spears that continued to grow in dark conditions (up to 4.32 μg g⁻¹ FW). Full article

This study examines the influence of vegetation on indoor daylight performance in school buildings located in the hot–humid climate of Chennai, India. With increasing urban development leading to the cutting or relocation of trees, their role in modulating interior daylight conditions has become critically relevant but remains underexplored in the literature. Recognizing a significant research gap in this area, this study employed a simulation-based approach using DesignBuilder 7.4 software. A government school in South Chennai, India, was chosen for this study. A total of 208 scenarios were generated by varying the window-to-wall ratio (WWR), facade orientation, floor level, and tree presence. Daylight performance was evaluated using spatial daylight autonomy (sDA), annual sunlight exposure (ASE), and useful daylight illuminance (UDI), based on IES LM-83-12 and LEED v4 standards. Simulation results showed that a 20% window-to-wall ratio (WWR) failed to meet daylight standards, while a 30–40% WWR with shading consistently performed well. Trees significantly improved daylight metrics, like sDA, UDI, and ASE, more so than orientation or floor level. This study urges regulatory mandates for climate-resilient schools, emphasizing fenestration and landscape integration. Full article

Background/Objectives: Vitamin D deficiency is a global epidemic. In certain populations, such as the United Arab Emirates (UAE), low nutritional intake of vitamin D, inadequate exposure to sunlight, and cultural dress codes can lead to deficiencies in blood vitamin D levels, predisposing them to musculoskeletal disorders, diabetes, and cardiovascular diseases. There are also notable associations between vitamin D deficiency, physical inactivity, and lower cognitive performance. The aim of this study was to determine how vitamin D status may affect physical inactivity and cognitive performance in a young UAE population. Methods: Primary data were obtained on vitamin D status, cardiorespiratory fitness, body composition, and blood profiles of students in the UAE. Following initial assessment, a cohort of vitamin D-deficient/insufficient individuals participated in a 10-week physical activity intervention (Group A), whilst another cohort was supplemented with 5000 IU vitamin D3 daily and an exercise intervention (Group B). Both groups underwent physiological and biochemical profiling, and the effects of vitamin D supplementation on cognitive function were assessed. Statistical analysis included paired samples t-tests between pre- and post-intervention values and the Wilcoxon signed rank test for within-group comparisons and the Mann–Whitney U test for between-group comparisons. Results: The findings suggest that physical exercise alone improves overall cardiorespiratory fitness, as shown by an increased VO₂ max (p < 0.05), while vitamin D supplementation combined with physical exercise did not significantly improve fitness over a 10-week period (p > 0.05). However, vitamin D combined with physical exercise significantly improved cognitive performance in Group B only, specifically in working memory, verbal memory, and cognitive flexibility (p < 0.05). Conclusions: This study highlights the need for targeted interventions such as physical exercise and vitamin D supplementation to be conducted at an early stage in order to improve physical and cognitive function and reduce the risk of disease. Full article

A novel composite material comprising titanium dioxide and layered double hydroxides (TiO₂/LDHs) was innovatively proposed and prepared using the co-precipitation method to overcome the shortcomings of titanium dioxide, such as low efficiency in separating electron–hole pairs induced by light and a low utilization rate of visible light. This material was used to study the visible-light-driven photocatalytic degradation of methylene blue. The experimental results show that by constructing efficient heterojunction structures through the alignment of interface band energies and regulating the interface charge transfer pathways, the recombination rate of photogenerated electron–hole pairs is significantly reduced, and the photocatalytic activity is greatly enhanced. Among the tested samples, the TiO₂/LDHs composite material with an aluminum-to-titanium molar ratio of 1:1 (AT11) demonstrated the best photocatalytic performance. Within 70 min of simulated sunlight exposure, the degradation rate of methylene blue reached 98.2%, and the optimal concentration of the catalyst was 1 g/L. The photocatalytic process follows a first-order kinetic model. After four cycles of use, the degradation efficiency of methylene blue by the AT11 composite material was 78.93%, demonstrating good stability. The free radical capture experiments indicated that the main active substances for the photocatalytic degradation of methylene blue were h⁺ and ·OH. The constructed TiO₂/LDHs heterostructure system significantly enhanced the photocatalytic performance of TiO₂ materials, which was conducive to the efficient utilization of solar energy. Full article

A current problem is the increase in skin damage, including cancer, caused mainly by prolonged exposure to ultraviolet rays from sunlight. Therefore, the aim of this work was to study the photoprotective effect to ultraviolet radiation of phenolics and acetogenic-rich extracts obtained from Annona muricata leaves applied to the skin of rats by means of gene expression in P53 and Rb, involved in tumor processes due to cell damage, in addition to the content of phenols, acetogenins and antioxidant activity present in the extract, which presented a total phenol content of 61.5 mg EAG/100 g of dry sample and flavonoids of 50 mg EQ/100 g. HPLC analysis revealed that the major compound was shikimic acid, followed by gallocatechin and 13 other phenols. DPPH analysis showed an inhibition of 64.37% and FRAP showed a value of 28,880 µmol Eq trolox/mL. The presence of acetogenins was verified by Kedde’s reagent in HPTLC. Histopathological findings in the treated groups (T4, T5) suggest thickening of the epidermis, which could be due to fibroblast proliferation. The results show a higher increase in P53 and Rb gene expression with the tested extracts compared to the positive control group, so it can be concluded that the extracts have positive effects. Full article

This study explores a green synthesis approach for creating a nanocomposite material consisting of zinc oxide (ZnO) nanoparticles decorated with reduced graphene oxide (rGO), utilizing Clitoria ternatea flower extract as a biogenic reducing agent. The objective was to leverage the phytochemicals present in the flower extract to form ZnO nanoparticles, enhance their properties through rGO integration, and evaluate their structural and photocatalytic characteristics. The nanocomposite was characterized using a comprehensive suite of techniques, including XRD, FTIR, UV–Vis spectroscopy, DLS, zeta potential, SEM, and EDAX. To assess the in vitro biocompatibility, an MTT assay was performed on the normal fibroblast cell line 3T3L1. The nanocomposite exhibited minimal cytotoxicity with over 86% cell viability at concentrations up to 320 μg/mL. Additionally, hemolysis assays demonstrated that the nanocomposite induced less than 5% hemolysis, indicating excellent hemocompatibility. In an in vivo evaluation, zebrafish embryos exhibited no deformities, and the cumulative hatchability was also not affected up to a dose of 50 μg/mL. The exploration of environmental remediation was studied using bromophenol dye degradation, which showed a 65% dye degradation within 30 min of exposure to the composite and sunlight. The outcome of the study showed successful formation of ZnO and its composite with rGO (CT-rGO-ZnO), exhibiting excellent biocompatibility and improved photocatalytic properties. The material demonstrates promise for applications in environmental remediation and energy-related fields. The environmentally friendly nature of the synthesis approach also makes it a valuable contribution toward sustainable nanotechnology. Full article

Background/Objectives: Intrinsic biomarkers, such as serum vitamin D levels and the conjunctival ultraviolet autofluorescence (CUVAF) area, have been proposed to quantify sunlight exposure. Evidence suggests that reduced outdoor activity during the SARS-CoV-2 pandemic accelerated the progression of myopia; however, there is little information on the impact of such restrictions on vitamin D levels and CUVAF area in populations with myopia. This study aims to assess the association between serum vitamin D levels and conjunctival ultraviolet autofluorescence area (CUVAF) in young adults with myopia during and after the pandemic, as well as its relationship with sun exposure habits and the use of skin protection measures. Methods: A prospective observational study was carried out. A total of 59 students participated, 32 with a diagnosis of myopia and 27 controls, during SARS-CoV-2 pandemic. Two serological tests for total 25-hydroxy vitamin D (D2 + D3) (Calciferol) were taken, activity habits and sun exposure were identified using the Intermountain Live Well Institute tool, and CUVAF images were taken post-pandemic. Results: In the 59 participants, we observed similar vitamin D concentrations between the myopic and control groups during and after the pandemic. However, analysis of CUVAF areas after the pandemic revealed that myopes had significantly smaller areas compared to controls (p < 0.05). Conclusions: The study demonstrated that using vitamin D as a biomarker for outdoor activity requires additional investigation; the CUVAF biomarker showed a significant association with myopia. Full article

Vitamin D (VD) plays a critical role in human health, with deficiencies linked to a range of adverse outcomes, including compromised immune function and increased disease risk. While environmental factors such as sunlight exposure and diet influence circulating VD levels, genetic variation is a significant and underappreciated contributor to interindividual differences in serum 25-hydroxyvitamin D [25(OH)D] concentrations. This review provides a comprehensive summary of genetic variants in key genes involved in VD synthesis (e.g., DHCR7, cyp2r1, cyp27b1), transport (GC), and metabolism (cyp24a1, cyp3a4), as well as in cholesterol transport proteins (SCARB1, CD36, NPC1L1). We examine how single-nucleotide polymorphisms (SNPs) and rare mutations in these genes affect enzyme activity, VD bioavailability, and overall 25(OH)D status. Importantly, we highlight evidence supporting gene-by-environment interactions and population-specific allele frequencies that further shape individual VD responses. In the context of clinical nutrition and precision health, these findings support the development of genomic risk scores (GRSs) to identify individuals at risk for deficiency or toxicity and guide personalized VD supplementation strategies. Regular monitoring of serum 25(OH)D alongside genetic screening may improve clinical outcomes by helping to achieve optimal VD immunosufficiency while minimizing the risk of adverse effects. Full article

This study explores the use of chlorography as a natural photographic developing technique that utilizes the decomposition of chlorophyll and other plant pigments through the action of sunlight. The developed images corresponded to previous research on changes in the iconography of the indigenous Salasaka people. In this context, this experimental project on natural photography is oriented toward the conservation of the ancestral knowledge of this community and the understanding of the native flora of Ecuador. We investigated the application of the contact image transfer technique with positive transparencies on leaves and flowers of 30 different species that grow in the Ecuadorian highlands, including leaves of vascular plants, as well as rose petals. The results showed that the clarity and contrast of chlorography depended on the plant species and exposure time. It was observed that fruit-bearing species produced more visible images than the leaves of other plants and rose petals, with species from the Passifloraceae family proving particularly effective. We interpreted these findings within the framework of plant photophysical mechanisms, proposing an inverse relationship between development efficiency and species’ non-photochemical quenching (NPQ) capacity. Furthermore, we interpreted the findings in relation to the photobleaching of pigments and compared chlorography with other natural photographic processes such as anthotypes. Key factors influencing the process were identified, such as the type of leaf, the intensity and duration of light, and the hydration of the plant material. It is concluded that chlorography is a viable, non-toxic, and environmentally friendly photographic alternative with potential applications in art, education, and research, although it presents challenges in terms of image permanence and reproducibility. Full article