Protective effects of a 1:1 mixture of 7,17-dihydroxy-DHA and 10,17-dihydroxy-DHA (SF) against blue light-induced retinal damages in A2E-laden ARPE-19 Cells.

The rye photoreceptor ScphyB integrates light signals to control development and architecture in Arabidopsis thaliana.

The Ottawa sunglasses at night study: A randomized controlled trial of blue-blocking glasses for mania.

• A general iron-catalyzed C3-alkylation of indene derivatives using primary alcohols as electrophilic partners is developed. Noticeably, this transformation was performed with a variety of substituted indenes and alcohols and was conducted at room temperature thanks to the use of blue light activation. • Noticeably the scope of this reaction is quite broad with both linear alkyl and benzylic alcohols and a good functional group tolerance was observed notably with halides, heteroaromatics, benzyloxy, amino, hydroxy, cyclopropyl and remoted C C double bonds which were not altered. Additionally, the reaction can be extended to 2-, 4- and 7-substituted indenes. (38 examples, 30–99% yields) • Control experiments permitted to propose a catalytic cycle explaining notably the role of the blue light. We reported herein a general iron-catalyzed C3-alkylation of indene derivatives using primary alcohols as electrophilic partners. Noticeably, this transformation was performed with a variety of substituted indenes and alcohols at room temperature thanks to the use of blue light activation. (38 examples, 30–99% yields) Control experiments permitted to propose a catalytic cycle explaining notably the role of the blue light.

Construction of transparent cellulose films with enhanced mechanical strength, fire resistance and UV to blue light shielding performance via hydrogen bond-electrostatic synergistic interaction

Mesoporous graphitic carbon nitride (g-C3N4) is an efficient heterogeneous photocatalyst. We report a redox-neutral trifluoromethylation of dienes using g-C3N4 as a visible-light organophotocatalyst in a supramolecular gel platform under aerobic conditions. The gel medium suppresses oxygen diffusion, stabilizes intermediates, and enhances the photocatalytic efficiency, affording high yields. Using CF3SO2Na as the radical source, the reaction proceeds via radical addition and cyclization, producing trifluoromethylated saturated heterocycles with excellent chemo- and regioselectivity. Blue LED light (456 nm) drives oxidative and reductive electron transfer on g-C3N4. The method requires no metals, oxidants, or inert atmosphere, underscoring its sustainability.

DNA double-strand break (DSB) represents the most severe form of DNA damage, and both defective and hyperactive repair can compromise genome stability. It is known that blue light promotes DSB repair by cryptochromes (CRYs)-enhanced STRUCTURAL MAINTENANCE OF CHROMOSOME 5/6 (SMC5/6) complex recruitment via ALTERATION/DEFICIENCY IN ACTIVATION 2B (ADA2b). Here, we report a negative regulatory module consisting of CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), an E3 ubiquitin ligase acting as a central repressor of photomorphogenesis, and ADA2b, a pivotal positive regulator of DNA repair, mediates light regulation of DSB repair. Light induces the accumulation of ADA2b, while COP1 physically interacts with ADA2b to mediate its ubiquitination and degradation through the 26S proteasome. The cop1-4 mutant exhibits enhanced DNA damage resistance under various light conditions, whereas the red/far-red photoreceptor phytochrome A and B (phyA/phyB) mutant displays hypersensitivity under red light. COP1 lies upstream of ADA2b but downstream of CRYs and phyB to regulate DNA repair. These findings reveal a pivotal role for the COP1-ADA2b module in CRYs- and phyA/phyB-mediated light regulation of DSB repair. The antagonistic regulation of ADA2b stability by photoreceptors and COP1 may dynamically calibrate DNA repair activity to maintain genome stability and optimize plant growth according to the fluctuating light conditions.

Blue light damage (BLD) is a complex process implicated in a variety of ocular diseases, including age-related macular degeneration and dry eye diseases. However, the molecular mechanisms underlying the BLD process remain largely unknown. In this study, using a mouse model, we identify photoreceptor cilium disruption as a key event in BLD and show that the UFMylation of kinesin family member 11 (KIF11) is decreased under BLD conditions. We further reveal that ubiquitin-fold modifier 1-specific ligase 1 (UFL1), the sole ligase for UFMylation, localizes to the basal body and is required for maintaining photoreceptor cilia. Strikingly, exposure to blue light disrupts the basal body localization of UFL1, leading to ciliary defects and subsequent photoreceptor dysfunction. Ufl1 knockout mice exhibit similar ciliary donlefects and retinal impairments. Importantly, intravitreal injection of agents that enhance UFMylation or ciliogenesis can mitigate the pathological changes induced by blue light exposure. These findings establish that UFL1-mediated ciliary integrity contributes to retinal deficits associated with BLD and demonstrate that targeting the UFMylation-cilium axis represents a promising therapeutic strategy for BLD-associated retinal diseases.

Psoriasis is a chronic, relapsing, immune-mediated systemic inflammatory disease that affects 2-3% of the global population. It affects the skin and leads to complications in multiple systems, severely impacting patients' quality of life. Although traditional topical therapies, systemic treatments, phototherapy, and emerging biological treatments have progressed in treating psoriatic dermatitis, they still cannot cure psoriasis and are associated with multiple side effects, including infections and phototoxicity. Building upon conventional narrowband ultraviolet B (NB-UVB) phototherapy, our research utilized upconversion nanoparticles (UCNPs) for in vivo phototherapy in the treatment of psoriasis. When taken up by macrophages, under 808 nm near-infrared (NIR) light with better tissue penetration, the UV light at 365 nm and blue light at 475 nm emitted by UCNPs could potentially modulate opsin 3, inhibiting pro-inflammatory (M1) macrophage (marked by IL-1β, iNOS, TNF-α, IL-23, IL-17A) and promoting anti-inflammatory (M2) macrophage (marked by Fizz 1 and Arginase 1), indicating that UCNPs-mediated phototherapy could switch psoriasis macrophages from M1 to M2. Transcriptomic profiling further revealed that this phototherapy reverses the IL‑23-induced psoriatic phenotype in RAW264.7 macrophages by upregulating M2‑related gene expression while downregulating key inflammatory effectors, which significantly improves psoriasis-like dermatitis without causing phototoxicity, highlighting the potential of phototherapy for psoriasis.

Controllable γ-radiation synthesis of conductive polymer-shelled AgNPs nanocomposites with enhanced antibacterial and antibiofilm activities.

As promising candidates for next-generation display technologies, perovskite light-emitting diodes (PeLEDs) continue to face bottlenecks of lower external quantum efficiency (EQE) and poor operational stability in the blue light region. Increasing the chlorine content represents a straightforward strategy for widening the bandgap to achieve blue emission. Nevertheless, the limited solubility of chlorine sources often leads to incomplete halogen incorporation, high defect density, and thus difficulty in obtaining pure blue emission with wavelengths shorter than 470 nm. In this study, we introduce a metastable precursor solution strategy that effectively modulates the colloidal chemistry to suppress CsCl precipitation, reduce colloidal size, and minimize halogen vacancies. These synergistic effects improve film coverage, enhance crystallinity, and lower the defect-state density. As a result, the optimized pure-blue PeLEDs achieve a peak EQE of 6.6% and exhibit stable electroluminescence at 468 nm. This work elucidates the fundamental mechanism through which precursor colloidal dynamics dictate the crystalline and electronic properties of perovskite films and provides a practical approach for optimizing the performance of mixed-halide perovskite optoelectronic devices.

The orange carotenoid protein (OCP) is a key photoreceptor in the photoprotection of cyanobacterial antenna complexes. Its peculiar activity is governed by a bound keto-carotenoid that functions both as a light sensor and an energy quencher. Upon blue light absorption, OCP transitions from an orange resting state (OCPO) to a red active state (OCPR) through carotenoid translocation into the N-terminal domain, followed by domain separation. Despite extensive studies, the molecular mechanism underlying photoactivation has remained unresolved. Here, we integrate excited-state nonadiabatic dynamics with enhanced sampling molecular dynamics, to reveal the entire photoactivation pathway at atomistic resolution. Our simulations identify a trans-to-cis photoisomerization of the bound keto-carotenoid as the critical photochemical event that initiates translocation. This cis isomer not only matches transient spectroscopic signatures observed experimentally but also exhibits the specific interactions with the protein required to enable translocation and domain separation. Finally, we uncover a multiphoton mechanism responsible for regenerating the all-trans configuration observed in the OCPR-antenna complex. These findings provide a mechanistic framework for OCP photoactivation, linking photochemistry with large-scale conformational changes. Our work highlights the central role of carotenoid photoisomerization and demonstrates the power of advanced atomistic simulations in dissecting the functional dynamics of photoreceptor proteins.

The phytochrome superfamily comprises photosensory proteins that enable organisms to perceive changes in light intensity and quality and is widespread across plants, fungi, algae, and microbes. In terrestrial plants, phytochromes sense red and far-red light to regulate key developmental and physiological processes. In marine environments, however, where red and far-red wavelengths penetrate only the upper few meters of water, the function of phytochromes has remained unclear. Recent work shows that diatom phytochromes exhibit photoreversible responses across a broad spectral range, extending beyond red and far-red, suggesting a role in underwater light sensing. Here, we examine the role of phytochromes in light perception and collective behavior in the marine diatom Phaeodactylum tricornutum. Comparing wild-type and phytochrome knockout strains under different light wavelengths reveals that activation of phytochromes by blue or far-red light synchronizes cell movements into a coordinated "wobbling dance." This behavior is absent in phytochrome-deficient mutants, demonstrating the essential role of phytochromes. Our results further suggest that this collective motion involves intercellular communication, potentially mediated by variable red and far-red autofluorescence. Together, these findings uncover a previously unrecognized light-driven social behavior in marine diatoms and highlight the ecological significance of phytochrome-mediated communication in microbial communities.

Achieving high morphological uniformity and mechanical strength is critical for the automation of watermelon grafting; yet, specific light protocols targeting these traits are lacking. This study employed LED lighting to regulate the morphological development of watermelon scion seedlings in a controlled plant factory environment. Using the watermelon cultivar ‘Heimeiling’ as the experimental material, three sequential experiments were conducted: (1) Under conditions of 95 μmol·m−2·s−1 light intensity and a 12 h photoperiod, seven red/blue light ratios and a white light control were tested to identify the appropriate light quality. (2) Under the R3B1 light quality, gradients of the daily light integral (DLI) ranging from 2.88 to 17.28 mol·m−2·d−1 were established by adjusting the light intensity and photoperiod to determine the optimal DLI. (3) Based on the above results, an orthogonal experiment was designed, with factors including the light quality (R7B1, R3B1, R1B1; where R7B1 represents 87.5% red light and 12.5% blue light), light intensity (120, 160, 200 μmol·m−2·s−1), and photoperiod (16 h, 20 h, 24 h) to identify the optimal light environment combination for mechanical grafting. Results indicated that while monochromatic red light induced excessive elongation and suppressed metabolism, the R3B1 spectrum significantly enhanced the stem diameter, mechanical strength, and carbon–nitrogen accumulation while maintaining hormonal balance. Regarding the daily light integral (DLI), seedlings exhibited an optimal performance at 11.52 mol·m−2·d−1. Lower DLI levels led to etiolation, whereas higher levels caused photoinhibition and PSII damage. Furthermore, orthogonal analysis revealed that light intensity was the dominant factor driving stem thickening and biomass accumulation, while light quality primarily regulated plant height. Consequently, a combination of R3B1 light quality, 200 μmol·m−2·s−1 intensity, and a 20 h photoperiod was identified as the optimal strategy to satisfy the stringent morphological requirements for mechanical grafting.

To analyse the effects of chromatic light (white, blue, red and green) and stimulus size (6/6 and 6/12) on pupil constriction, Zernike coefficients and the accommodative response curve using wavefront aberrometry across a wide age range of healthy subjects. One hundred and sixty-four right eyes from participants aged 20-75 years were evaluated. All subjects showed normal near visual function for their age. Wavefront aberrations were measured under scotopic conditions using the IRX3 aberrometer. Accommodation was induced from 0 to 10D in the younger group and from 0 to 5D in the full sample. Stimuli varied in colour and size. Pupil diameter and Zernike coefficients were analysed, rescaling all maps to a 3.00 and a 3.65 mm pupil, respectively. Mean pupil diameter ± standard deviation decreased progressively with increasing accommodative demand by 0.51 ± 0.06 mm in the full sample (0-5D) and by 2.09 ± 0.11 mm in the younger group (0-10D). The greatest changes were observed under white light and larger stimuli. The Zernike component C(2,0) varied significantly across all filters, optotype sizes and in both the total (p < 0.003) and the younger (p < 0.0009) groups. However, C(4,0) showed significant changes in all conditions for the younger group (p < 0.0009), particularly at higher demands. An initial overaccommodation of approximately 1D at baseline was followed by a progressive lag beyond 5D, being more pronounced under red light, where the accommodative response was lowest, while white light consistently elicited the strongest response. Larger stimuli induced greater responses than smaller ones, especially at high demands. Accommodation efficiency varies with wavelength and stimulus size: white and blue lights triggered greater pupil constriction and accommodation than red and green, with corresponding changes in defocus and spherical aberration. Small stimuli improved low-demand responses, while larger ones were more effective at higher demands.

In nature, leaves often undergo transient increases in light intensity. Slow stomatal and biochemical responses restrict CO2 diffusion and fixation during these transitions, delaying photosynthetic induction and lowering light use efficiency. As blue light (BL) efficiently promotes stomatal opening, it has been hypothesized that BL enrichment could alleviate diffusional limitations and accelerate photosynthetic induction. Yet, existing evidence is inconsistent and a comprehensive assessment is needed. Gas exchange during consecutive transitions from darkness to low light (LL), LL to high light (HL), and postillumination was measured in wheat leaves under three to six levels of BL fraction in moderate and adverse environments, including high measurement vapor pressure deficit, elevated measurement CO2 concentrations, and progressive drought. Blue light enrichment accelerated photosynthetic induction in a dose-dependent manner by reducing both diffusional and biochemical limitations. Multi-level mechanisms, such as stomatal behavior and transcriptional adjustments, contributed to reducing diffusional limitations. The acceleration of photosynthetic induction by BL enrichment persisted in adverse environments. Compared with the BL-free condition, BL enrichment enhanced photosynthetic carbon gain during the HL induction by up to 60%. These results suggest that BL-induced stomatal opening is crucial for photosynthetic performance in fluctuating light environments.

The blue light using flavin (BLUF) domain functions as a versatile photoreceptor switch mediated by proton-coupled electron transfer (PCET). Despite extensive ultrafast spectroscopic studies on BLUF mutants, the mechanistic role of key aromatic residues in regulating PCET pathways remains unclear. Here, we employ QM(MS-CASPT2)/MM calculations to elucidate the PCET mechanism of the FMN-Glu48-Trp6 (FMN-E-W) and FMN-Glu48-Tyr6 (FMN-E-Y) mutants. In the forward reaction, FMN-E-W follows a stepwise mechanism initiated by a PCET process from Glu48 to FMN, followed by another proton transfer from Trp6 to Glu48. In contrast, FMN-E-Y proceeds via a concerted PCET pathway without a stable intermediate. For the reverse process, FMN-E-W undergoes an electron transfer from FMN to Trp6 accompanied by a proton transfer to Trp6, followed by another proton transfer back to Glu48, whereas the reverse proton transfer in FMN-E-Y is both energetically and kinetically suppressed. These findings explain how aromatic residues tune PCET from stepwise to concerted, therefore supplying valuable insights for rationally designing photoresponsive proteins.

Abstract In past few years, significant advances have been achieved in the development of green and red-light emitting perovskite halide nanocrystals (NCs). But in comparison, the performance of blue light emitting perovskite NCs is not satisfactory. In this work we successfully synthesized La3+ and Cl- doped MAPbBr3 NCs by simple ligand assisted reprecipitation technique to achieve stale blue light emission. Here we concomitantly realized the doping of La3+ into the MAPbBr3 NC system at two different concentration and also regulated the Cl/Br ratio by introducing controlled amount of LaCl3 to the reaction mixture. Our study is first to explore the doping of La3+ ions into the MAPbBr3 NCs and study their optical properties. The La3+doping maintains structural integrity without inducing phase changes. Temperature-dependent photoluminescence studies reveal higher exciton binding energy, contributing to improved luminescence stability. The La3+ doping shows faster nucleation process leading to reduced NC size and also increase in shallow defect states. This is further explained in time resolved photoluminescence studies. The La3+-doped NCs exhibit blue emission centred at 470 nm, covering 92.61% of the Rec 2020 colour space, offering a promising, cost-effective alternative for next-generation blue light-emitting materials in display applications.

miRNA 183 is part of the miRNA-183/96/182 cluster, which is known to play a decisive role in fine-tuning the activity of gene expression in sensory systems, particularly in the retina. Although miR-183 is essential for retinal gene expression in mammals, the contributions of miR-183 to mRNA expression and photoreceptor development and function in other classes of animals have not been fully elucidated. Danio rerio have a diverse photoreceptor system, with cone photoreceptors sensitive to red, green, blue and ultraviolet (UV) light. We generated knockout zebrafish by deleting the whole seed sequence of miR-183. RNAscope results show no expression of mature miR-183 and decreased expression of miR-182 in both dorsal and ventral KO retinas. The number of UV and blue photoreceptors decreased, and the photoreceptors showed shortening or loss of their outer segments. In the absence of miR-183, the transcription levels of phototransduction genes were altered differentially at 3 and 12 months of age. Finally, photoreceptor-only electroretinogram (PIII) signals showed attenuated amplitudes of red and green-sensitive photoreceptor subtypes while the b-wave amplitudes reflecting second order retinal neuron activity, were decreased in response to the UV-, blue-, and red-stimulating wavelengths. These results reveal a novel microRNA regulatory network in teleost fish and indicate that miR-183 plays a facilitative role in retinal development and function, especially for short-wavelength-sensitive photoreceptor subtypes.

Anti-melanogenic effect of <i>Ajuga decumbens</i> callus extract cultured by irradiating LED blue light in α-MSH-induced B16F10 melanoma cells