White Light Exposure Research Articles

Exceptionally crystalline nature of CrO3‐Cr2O3/Ppy nanocomposite as a prospective photoelectrode for efficient green hydrogen generation in the context of environmentally friendly water‐splitting reactions using sanitized water

AbstractThis research introduces a novel technique for transforming wastewater into renewable hydrogen gas using an innovative photoelectrode composed of CrO3‐Cr2O3/polypyrrole (Ppy), synthesized through a one‐pot method. The photoelectrode is applied to split wastewater under different light conditions: darkness, white light, and monochromatic light. In the absence of light, the CrO3‐Cr2O3/Ppy photoelectrode produces a photocurrent density (Jph) value of 0.54 mA cm−2, which significantly increases to 0.78 mA cm−2 under white light exposure. The Jph values range from 0.68 to 0.76 mA cm−2 at wavelengths between 730 and 340 nm, showcasing the photoelectrode's remarkable sensitivity. This sensitivity highlights the potential of the photoelectrode to efficiently capture light energy for applications in wastewater treatment and green hydrogen production. By utilizing wastewater as a renewable energy source and employing the CrO3‐Cr2O3/Ppy photoelectrode, this approach addresses environmental concerns and energy needs concurrently. The proposed prototype for a three‐electrode cell aims to directly produce hydrogen gas from wastewater, with the ultimate goal of generating hydrogen suitable for industrial applications. This innovative solution not only addresses wastewater treatment but also transforms it into a valuable source of green energy, emphasizing the potential for positive environmental and energy‐related advancements.

Efficacy of Morning Shorter Wavelength Lighting in the Visible (Blue) Range and Broad-Spectrum or Blue-Enriched Bright White Light in Regulating Sleep, Mood, and Fatigue in Traumatic Brain Injury: A Systematic Review.

Traumatic brain injury (TBI) profoundly affects sleep, mood, and fatigue, impeding daily functioning and recovery. This systematic review evaluates the efficacy of morning shorter wavelength lighting in the visible (blue) range and broad-spectrum or blue-enriched bright white light exposure in mitigating these challenges among TBI patients. Through electronic database searches up to May 2023, studies assessing sleep, circadian rhythm, sleepiness, mood, and fatigue outcomes in TBI patients exposed to morning shorter wavelength lighting in the visible (blue) range and broad-spectrum or blue-enriched bright white light were identified. Seven studies involving 309 participants met the inclusion criteria. Results indicated consistent advancement in sleep timing among individuals with mild TBI, alongside improvements in total sleep time, mood, and reduced sleepiness with both types of light exposure, particularly in mild TBI cases. Notably, two studies demonstrated alleviation of fatigue exclusively in severe TBI cases following light exposure. Despite promising findings, evidence remains limited, emphasizing the need for future research with standardized protocols to confirm the potential and optimize the benefits of light therapy for TBI recovery.

Transcriptome Analysis Reveals Candidate Genes for Light Regulation of Elsinochrome Biosynthesis in Elsinoë arachidis

Light regulation is critical in fungal growth, development, morphogenesis, secondary metabolism, and the biological clock. The fungus Elsinoë arachidis is known to produce the mycotoxin Elsinochrome (ESC), a key factor contributing to its pathogenicity, under light conditions. Although previous studies have predominantly focused on the light-induced production of ESC and its biosynthetic pathways, the detailed mechanisms underlying this process remain largely unexplored. This study explores the influence of light on ESC production and gene expression in E. arachidis. Under white light exposure for 28 days, the ESC yield was observed to reach 33.22 nmol/plug. Through transcriptome analysis, 5925 genes were identified as differentially expressed between dark and white light conditions, highlighting the significant impact of light on gene expression. Bioinformatics identified specific light-regulated genes, including eight photoreceptor genes, five global regulatory factors, and a cluster of 12 genes directly involved in the ESC biosynthesis, with expression trends confirmed by RT-qPCR. In conclusion, the study reveals the substantial alteration in gene expression associated with ESC biosynthesis under white light and identifies potential candidates for in-depth functional analysis. These findings advance understanding of ESC biosynthesis regulation and suggest new strategies for fungal pathogenicity control.

Exploring the spectral properties and potential applications of dimethylamine-modified porphyrin and chlorin dyes

The synthesis, structural characterization, and optical properties of new free-base and metalated dimethylamine-based porphyrin (1, 1a) and chlorin (2, 2a) derivatives are presented. The synthetic approach is based on the peripheral substitution of the para-fluor atoms of the commercially available 5,10,15,20-tetrakis(pentafluorophenyl)-21H,23H-porphyrin (H2TPPF20) by dimethylamine (H2Por 1), following the preparation of the analogous chlorin dye (H2Chl 2) using N-methylglycine and p-formaldehyde. Both compounds were then metalated with zinc acetate to perform the corresponding ZnPor 1a and ZnChl 2a dyes. Several photophysical parameters were determined, including absorption and emission features at 298 K (e.g., molar absorptivity coefficients, λ absorption maxima of Soret and/or Q bands, λemission maxima, and ratio of long- to short-wavelength emission intensity), fluorescence quantum yield (ФF), stability (under dark conditions), and photostability (under white light exposure at irradiance of 50 mW.cm−2). The photophysical results were determined and compared for the type of meso-substituted scaffold selected – A4-type – of free-base (1, 2) and zinc(II) complex (1a, 2a). The four compounds exhibit high dark stability in DMF (absorption reduction intensity < 3 %). The Pors 1 and 1a have also high photostability (absorption reduction intensity < 1.5 %), but H2Chl 2 and ZnChl 2a present a considerable absorption reduction, 14.3 % and 22.3 %, respectively. The ФF of the ZnPor 1a (ФF = 0.02) and H2Por 1 (ФF = 0.02) are lower than those of ZnChl 2a (ФF = 0.06) and H2Chl 2 (ФF = 0.09). The developed compounds present potential applications in nonlinear optics, biomarkers, and/or solar cells.

Prolonged Blue Light Exposure Does Not Elicit Adverse Changes to Physical Activity in Male Mice

Color plays a role in human and animal circadian rhythm patterns, behaviors, and emotional responses. Environments containing blue colors improve information storage in humans and reproductive success in animals; however, environments containing blue light influence behavioral and emotional responses in rodents and humans in adverse ways. Exposure to blue light alters sleeping patterns, induces the stress response, and elicits depressive behaviors. These initial responses then affect awake time functionality and productivity. Under normal physiological conditions, mice, when provided access to an in-cage running wheel, exhibit high levels of nocturnal physical activity behavior. It is unknown if this nocturnal behavior changes after prolonged blue light exposure. Therefore, this project's hypothesis is wheel running utilization decreases after exposure to blue light during the diurnal restful period in the normally nocturnal mouse. The purpose of this study was to expose mice to overhead blue LED lights during the daytime rest period and to examine nighttime physical activity patterns. Daily wheel running distance, duration, and speed monitoring in C57BL/6j male mice (n=12) occurred for 21 days. During the second week of the study, an experimental group (n=6) underwent blue light-emitting diode (LED) light exposure, and a control group (n=6) experienced white LED light exposure at the same intensity. The lights were on a 12-hour light/dark cycle at full brightness during the exposure period. Differences in wheel running distance, duration, and speed following exposure to blue LED light were assessed via individual two-way (group by phase of study) ANOVAs. Blue LED light exposure did not appear to affect average daily wheel running distance [F=0.42, p=0.57], duration [F=0.79, p=0.42], or speed [F=0.08, p=0.87]. Following exposure to blue LED light during the restful diurnal period, wheel running remained stable. This lack of effect indicates that mechanisms may exist to protect mice from the adverse effects associated with blue light exposure, especially as it pertains to participating in routine physical activity. These postulated mechanisms may allow robust participation in physical activity-related behaviors in these animals and represent a potential biological regulator that could aid in mitigating the adverse effects of blue light exposure experienced in humans. All funding for this research was provided by the Union University Department of Biology. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effects of light-emitting diodes on the morphology and accumulation of glucosinolates, carotenoids and phenolic acids in red kale sprouts

Kale (Brassica oleracea var. acephala) has gained popularity as a nutritious and phytochemical-rich vegetable. This study has investigated the effects of three LED treatments (white, blue, and red) on the accumulation of secondary metabolites in kale sprouts. Ten DAS, the kale sprouts were harvested, and growth measurements were measured. Furthermore, selected sprouts were stored at -80 °C for further biochemical analysis, namely, phenolic acids, glucosinolates, and carotenoids. Sprouts irradiated with red LED light showed the best SL, RT, and FW values. For total GSLs, we found that kale sprouts irradiated with white LED lights showed the best results (41.59±0.41 μmol/g DW). Among the aliphatic GSLs, we found that progoitrin presented the best results under blue LED light (17.93±0.49 µmol/g DW), and among the indolic GSLs, glucobrassicin showed the best results under white and red LED light. The highest concentration of total carotenoids was found in kale sprouts under white LED light exposure (3341.27±206.96 μg/g DW). Individually, β-carotene was observed in high concentration under white LED light (1935.13±87.21 μg/g DW). Among the PAs, chlorogenic acid was found in the highest concentration in the treatments under white LED light (45.78±0.73 µg/g DW). In general, kale sprouts irradiated with white LED light showed high contents of GSLs, carotenoids, and PAs. Regarding morphological characteristics, kale sprouts under red LED light showed the most promise. This research offers a valuable approach to enhancing the phytochemicals found in kale sprouting.

Nonvolatile Reconfigurable Logic Device Based on Photoinduced Interfacial Charge Trapping in van der Waals Gap.

Due to the increasing complexity in miniaturization of electronic devices, reconfigurable field-effect transistors (RFETs) have emerged as a solution. Although the foundational concepts of RFETs have matured over two decades, ongoing breakthroughs are needed to address challenges such as improving the device performance as well as achieving balanced symmetry between n-type and p-type transport modes with long-term stability. Herein, we present a nonvolatile WSe2-based RFET that utilizes photoassisted interfacial charge trapping at the h-BN and SiO2 interface. Unlike typical RFETs with two gate electrodes, our RFETs achieved polarity control with a single operating gate activated exclusively under white-light exposure. The threshold voltage was tunable, ranging from 27.4 (-31.6 V) to 0.9 (+19.5 V), allowing selective activation of n-type (p-type) operation at VGS = 0 V. Additionally, our WSe2-based RFETs show superior repeatability and long-term stability. Leveraging these advantages, various reconfigurable logic circuits were successfully demonstrated, including complementary inverters and switch circuits as well as pull-up and pull-down circuits, highlighting the potential of WSe2 FETs for future advancements of integrated circuits.

Green Light-Triggered Photocatalytic Anticancer Activity of Terpyridine-Based Ru(II) Photocatalysts.

The relentless increase in drug resistance of platinum-based chemotherapeutics has opened the scope for other new cancer therapies with novel mechanisms of action (MoA). Recently, photocatalytic cancer therapy, an intrusive catalytic treatment, is receiving significant interest due to its multitargeting cell death mechanism with high selectivity. Here, we report the synthesis and characterization of three photoresponsive Ru(II) complexes, viz., [Ru(ph-tpy)(bpy)Cl]PF6 (Ru1), [Ru(ph-tpy)(phen)Cl]PF6 (Ru2), and [Ru(ph-tpy)(aip)Cl]PF6 (Ru3), where, ph-tpy = 4'-phenyl-2,2':6',2″-terpyridine, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline, and aip = 2-(anthracen-9-yl)-1H-imidazo[4,5-f][1,10] phenanthroline, showing photocatalytic anticancer activity. The X-ray crystal structures of Ru1 and Ru2 revealed a distorted octahedral geometry with a RuN5Cl core. The complexes showed an intense absorption band in the 440-600 nm range corresponding to the metal-to-ligand charge transfer (MLCT) that was further used to achieve the green light-induced photocatalytic anticancer effect. The mitochondria-targeting photostable complex Ru3 induced phototoxicity with IC50 and PI values of ca. 0.7 μM and 88, respectively, under white light irradiation and ca. 1.9 μM and 35 under green light irradiation against HeLa cells. The complexes (Ru1-Ru3) showed negligible dark cytotoxicity toward normal splenocytes (IC50s > 50 μM). The cell death mechanistic study revealed that Ru3 induced ROS-mediated apoptosis in HeLa cells via mitochondrial depolarization under white or green light exposure. Interestingly, Ru3 also acted as a highly potent catalyst for NADH photo-oxidation under green light. This NADH photo-oxidation process also contributed to the photocytotoxicity of the complexes. Overall, Ru3 presented multitargeting synergistic type I and type II photochemotherapeutic effects.

Toxicological assessment of photoactivated tetra-cationic porphyrin molecules under white light exposure in a Caenorhabditis elegans model

Photodynamic therapy (PDT) utilizes the potential of photosensitizing substances to absorb light energy and produce reactive oxygen species. Tetra-cationic porphyrins, which have organic or coordination compounds attached to their periphery, are heterocyclic derivatives with well-described antimicrobial and antitumoral properties. This is due to their ability to produce reactive oxygen species and their photobiological properties in solution. Consequently, these molecules are promising candidates as new and more effective photosensitizers with biomedical, environmental, and other biomedical applications. Prior to human exposure, it is essential to establish the toxicological profile of these molecules using in vivo models. In this study, we used Caenorhabditis elegans, a small free-living nematode, as a model for assessing toxic effects and predicting toxicity in preclinical research. We evaluated the toxic effects of porphyrins (neutral and tetra-cationic) on nematodes under dark/light conditions. Our findings demonstrate that tetra-methylated porphyrins (3TMeP and 4TMeP) at a concentration of 3.3 µg/mL (1.36 and 0.93 µM) exhibit high toxicity (as evidenced by reduced survival, development, and locomotion) under dark conditions. Moreover, photoactivated tetra-methylated porphyrins induce higher ROS levels compared to neutral (3TPyP and 4TPyP), tetra-palladated (3PdTPyP and 4PdTPyP), and tetra-platinated (3PtTPyP and 4PtTPyP) porphyrins, which may be responsible for the observed toxic effects.

Effect of Chitosan-Riboflavin Bioconjugate on Green Mold Caused by Penicillium digitatum in Lemon Fruit.

Penicillium digitatum is the causal agent of green mold, a primary postharvest disease of citrus fruits. This study evaluated the efficacy of a novel photoactive chitosan-riboflavin bioconjugate (CH-RF) to control green mold in vitro and in lemon fruit. The results showed total inhibition of P. digitatum growth on APDA supplemented with CH-RF at 0.5% (w/v) and a significant reduction of 84.8% at 0.25% (w/v). Lemons treated with CH-RF and kept under controlled conditions (20 °C and 90-95% relative humidity) exhibited a noteworthy reduction in green mold incidence four days post-inoculation. Notably, these effects persisted, with all treatments remaining significantly distinct from the control group until day 14. Furthermore, CH-RF showed high control of green mold in lemons after 20 days of cold storage (5 ± 1 °C). The disease incidence five days after cold storage indicated significant differences from the values observed in the control. Most CH-RF treatments showed enhanced control of green mold when riboflavin was activated by white-light exposure. These findings suggest that this novel fungicide could be a viable alternative to conventional synthetic fungicides, allowing more sustainable management of lemon fruit diseases.

Bacterial-mediated FRET between AIE and ACQ photosensitizers for enhanced antimicrobial photodynamic therapy

Antimicrobial photodynamic therapy (aPDT) effectively treats multidrug-resistant bacterial infections by utilizing photosensitizers to generate cytotoxic reactive oxygen species. Exploiting fluorescence resonance energy transfer (FRET) effect shows great potential for enhancing the efficacy of aPDT. Typically, this method involves encapsulating fluorescent molecules, including photosensitizers, into nanomaterials or coadsorbing them onto materials. Here, we develop a strategy that directly utilizes bacteria as carriers to bring two types of photosensitizers together to induce the FRET. We designed an aggregation-induced emission (AIE) photosensitizer (CPVBP3) and an aggregation-caused quenching (ACQ) photosensitizer (TPP3), both featuring the same bacterial membrane-targeting group to direct them to bacteria. Under white light exposure (12 J/cm2), the bactericidal effect of the combination of CPVBP3 and TPP3 at 5 µM each on Escherichia coli (4.7 log10) was much stronger than their individual use at 5 or 10 µM, highlighting synergistic antibacterial action. In Escherichia coli, TPP3 absorbed the fluorescence of CPVBP3, reducing its lifetime from 0.98 ns to 0.74 ns, confirming the occurrence of FRET. This combination also demonstrated a significantly stronger synergistic aPDT effect on Acinetobacter baumannii. Moreover, CPVBP3 synergized with methylene blue against Escherichia coli, indicating the universality of this strategy. Additionally, the efficacy and biosafety of this therapeutic approach were validated in a mouse wound model infected with Escherichia coli. In summary, this FRET strategy overcomes the limitations associated with the need for pre-binding photosensitizers with materials and the challenge of these mixtures penetrating bacteria (for greater damage), ultimately opening new avenues for further enhancing the efficacy of aPDT.

The Impact of Photopigment Bleaching on the Human Rod Photoreceptor Subretinal Space Measured Via Optical Coherence Tomography.

The purpose of this study was to investigate rod photopigment bleaching-driven intrinsic optical signals (IOS) in the human outer retina and its measurement repeatability based on a commercial optical coherence tomography (OCT) platform. The optical path length of the rod photoreceptor subretinal space (SRS), that is, the distance between signal bands of rod outer segment tips and retinal pigment epithelium, was measured in 15 healthy subjects in ambient light and during a long-duration bleaching white-light exposure. On 2 identical study days (day 1 and day 2 [D1 and D2]), light stimulation resulted in a significant decrease in rod SRS by 21.3 ± 7.6% and 19.8 ± 8.5% (both P<0.001), respectively. The test-retest reliability of the SRS maximum change of an individual subject was moderate for single measures (intraclass correlation coefficient [ICC] = 0.730, 95% confidence interval [CI] = 0.376, 0.900, P<0.001) and good for average measures (ICC = 0.844, 95% CI = 0.546, 0.947, P<0.001). The mean area under the stimulus response curve with values of 14.8 ± 9.4 and 15.5 ± 7.5µm × minutes (P=0.782) showed excellent agreement between the stimulus response on D1 and D2. Intermittent dark adaptation of the retina led to an initial increase of the SRS by 6.1% (P=0.018) and thereafter showed a decrease toward baseline, despite continued dark adaptation. The data indicate the potential of commercial OCT in measuring slow IOS in the outer retina suggesting that the rod SRS could serve as a biomarker for photoreceptor function. The presented approach could provide an easily implementable clinical tool for the early detection of diseases affecting photoreceptor health.

Influence of white-light-emitting diodes on primary visual cortex layer 5 pyramidal neurons (V1L5PNs) and remodeling by blue-light-blocking lenses

Studies have explored the consequences of excessive exposure to white-light-emitting diodes (LEDs) in the retina. Hence, we aimed to assess the implications of such exposure on structural alterations of the visual cortex, learning and memory, and amelioration by blue-light-blocking lenses (BBLs). Eight-week-old Wistar rats (n = 24) were used for the experiment and divided into four groups (n = 6 in each group) as control, white LED light exposure (LE), BBL Crizal Prevencia-1 (CP), and DuraVision Blue-2 (DB). Animals in the exposure group were exposed to white LED directly for 28 days (12:12-h light/dark cycle), whereas animals in the BBL groups were exposed to similar light with BBLs attached to the LEDs. Post-exposure, a Morris water maze was performed for memory retention, followed by structural analysis of layer 5 pyramidal neurons in the visual cortex. We observed a significant difference (P < 0.001) in the functional test on day 1 and day 2 of training in the LE group. Structural analysis of Golgi-Cox-stained visual cortex layer 5 pyramidal neurons showed significant alterations in the apical and basal branching points (p < 0.001) and basal intersection points (p < 0.001) in the LE group. Post hoc analysis revealed significant changes between (p < 0.001) LE and CP and (p < 0.001) CP and DB groups. Constant and cumulative exposure to white LEDs presented with structural and functional alterations in the visual cortex, which are partly remodeled by BBLs.

Lettuce seedlings quality: The effects of white and blue light exposure

Lettuce seedlings quality: The effects of white and blue light exposure

The effect of a dynamic lighting schedule on neurobehavioral performance during a 45-day simulated space mission.

We previously reported that during a 45-day simulated space mission, a dynamic lighting schedule (DLS) improved circadian phase alignment and performance assessed once on selected days. This study aimed to evaluate how DLS affected performance on a 5-minute psychomotor vigilance task (PVT) administered multiple times per day on selected days. Sixteen crewmembers (37.4 ± 6.7 years; 5F) underwent six cycles of 2 × 8-hour/night followed by 5 × 5-hour/night sleep opportunities. During the DLS (n = 8), daytime white light exposure was blue-enriched (~6000K; Level 1: 1079, Level 2: 76 melanopic equivalent daytime illuminance (melEDI) lux) and blue-depleted (~3000-4000K; L1: 21, L2: 2 melEDI lux) 3 hours before bed. In the standard lighting schedule (SLS; n = 8), lighting remained constant (~4500K; L1: 284, L2 62 melEDI lux). Effects of lighting condition (DLS/SLS), sleep condition (5/8 hours), time into mission, and their interactions, and time awake on PVT performance were analyzed using generalized linear mixed models. The DLS was associated with fewer attentional lapses (reaction time [RT] > 500 milliseconds) compared to SLS. Lapses, mean RT, and 10% fastest/slowest RTs were worse following 5 compared to 8 hours of sleep but not between lighting conditions. There was an effect of time into mission on RTs, likely due to sleep loss. Overall performance differed by time of day, with longer RTs at the beginning and end of the day. There were more lapses and slower RTs in the afternoon in the SLS compared to the DLS condition. Future missions should incorporate DLS to enhance circadian alignment and performance. This paper is part of the Sleep and Circadian Rhythms: Management of Fatigue in Occupational Settings Collection.

Effect of White Noise and Light Exposure on Some Enzymes in Rat Testicular Tissue

By definition, white noise (WN) is a type of sound that consists of a combination of various frequencies. Noise is an important source of environmental stress for humans and other living things and has a strong stimulating effect on light, circadian rhythm, hormonal, and neuro-behavioral levels. When faced with stressful situations, organisms produce a substantial quantity of free radicals, leading to alterations in the oxidative system. The objective of this research is to examine how environmental stressors like WN and light impact the activities of enzymes involved in testicular carbonic anhydrase (CA), catalase (CAT), and glutathione peroxidase (GPx). A total of 18 male Sprague-Dawley rats were divided into three groups. The first was the control group (not exposed to stress, kept at 12/12 light-dark cycle and 24±2°C normal ambient temperature). The second group, known as the WN 60' group, experienced 60 minutes of white noise exposure per day for 14 consecutive days at 90 dB. The third group, referred to as the WN 60' + non daylight group, underwent 60 minutes of white noise exposure at 90 dB combined with 24 hours of continuous light exposure every other day. At the conclusion of the study, the testicular tissues were homogenized and centrifuged, followed by the spectrophotometric measurement of enzyme activities.&#x0D; As a result, when we compared the control group with both WN and WN + light exposure; A decrease was observed for CA enzyme in both applications, and an increase was observed in CAT and GPx enzymes in both applications.&#x0D; As a result, when we compared the control group with both BG and BG + light exposure; A decrease was observed for CA enzyme in both applications, and an increase was observed in CAT and GPx enzymes in both applications.

Metarhizium pingshaense photolyase expression and virulence to Rhipicephalus microplus after UV-B exposure.

The current study examined the impact of ultraviolet (UV)-B radiation in Metarhizium pingshaense blastospores' photolyase expression and their virulence against Rhipicephalus microplus. Blastospores were exposed to UV under laboratory and field conditions. Ticks were treated topically with fungal suspension and exposed to UV-B in the laboratory for three consecutive days. The expression of cyclobutane pyrimidine dimmers (CPDs)-photolyase gene maphr1-2 in blastospores after UV exposure followed by white light exposure was accessed after 0, 8, 12, 24, 36, and 48 h. Average relative germination of blastospores 24 h after in vitro UV exposure was 8.4% lower than 48 h. Despite this, the relative germination of blastospores exposed to UV in the field 18 h (95.7 ± 0.3%) and 28 h (97.3 ± 0.8%) after exposure were not different (p > 0.05). Ticks treated with fungus and not exposed to UV exhibited 0% survival 10 days after the treatment, while fungus-treated ticks exposed to UV exhibited 50 ± 11.2% survival. Expression levels of maphr1-2 8, 12, and 24 h after UV-B exposure were not different from time zero. Maphr1-2 expression peak in M. pingshaense blastospores occurred 36 h after UV-B exposure, in the proposed conditions and times analyzed, suggesting repair mechanisms other than CPD-mediated-photoreactivation might be leading blastospores' germination from 0to 24 h.

Procedural Promotion of Wound Healing by Graphene-Barium Titanate Nanosystem with White Light Irradiation.

Wound healing is a continuous and complex process that comprises multiple phases including hemostasis, inflammation, multiplication (proliferation) and remodeling. Although a variety of nanomaterials have been developed to control infection and accelerate wound healing, most of them can only promote one phase but not multiple phases, resulting in lower efficient healing. Although various formulations such as nitric oxide releasing wound dressings were developed for dual action, the nanostructure synthesis and the encapsulation process were complex. Here, we report on the design of graphene-barium titanate nanosystem to procedural promote the wound healing process. The antibacterial effect was assessed in Gram-negative Escherichia coli bacteria (E. coli) and Gram-positive Staphylococcus aureus bacteria (S. aureus), the cell proliferation and migration experiment was investigated in mouse embryonic fibroblast (NIH-3T3) cells, and the wound healing effect was analyzed in female BALB/c mice with infected skin wound on the back. Results showed that graphene-barium titanate nanosystem could generate abundant ROS to kill both E. coli and S. aureus. The growth curves, bacterial viability, colony number formation and scanning electron microscopy (SEM) images of E. coli and S. aureus all confirmed the antibacterial effect. Cell Counting Kit-8 (CCK-8) assay displayed that GBT possesses great biocompatibility. EdU assay showed that GBT plus white light irradiation significantly promoted the proliferation and migration of NIH-3T3 cells. Scratch assay found that GBT could achieve a fast scratch closure compared to the control. In vivo wound healing effect indicates that GBT can accelerate wound repair procedure. GBT nanocomposite is capable of programmatically accelerating wound healing through multiple stages, including production of a large amount of ROS after white light exposure to effectively kill E. coli and S. aureus to prevent wound infection and as a scaffold to accelerate fibroblast proliferation and migration to the wound to accelerate wound healing.

Impact of repeated morning bright white light exposures on attention in a simulated office environment

Attention is essential to the work. This study investigated the effects of two different light pulses on a simple attention task. In addition, the effects of subsequent exposure to constant but different illuminance levels on the continuation of the simple attention task and a subsequent complex attention task were examined. A total of 56 subjects were assigned in random order to two white light interventions that were repeated five times during the morning. Each light intervention consisted of a brief light pulse followed by constant light exposure and differed in temporal dimming dynamics and corneal illuminance. Subjective and psychometric parameters were recorded several times during light exposure. Heart rate variability (HRV) was derived from continuous electrocardiograms. Subjects showed improved reaction speed in the simple attention task, accompanied by higher HRV under a brighter light pulse without habituation by repetition. This difference in simple attention performance disappeared when light exposure remained the same after the light pulse. In addition, higher reaction speed and HRV were observed in the complex attention task under constant bright light exposure. Intermittent bright light seems promising to acutely improve attentional performance in office workplaces. Future research is needed to investigate daytime light effects on other work-related cognitive functions.

0316 A Case Report: Comparing Sleep with and without blue light blockers

Abstract Introduction Blue light filtered eyewear is popular. Studies have looked at the effect of using blue light blockers in the evening but data is lacking on the effect of wearing blue light blockers (BLB) through the day. In this study we compared the effects of wearing BLB all day, on sleep and daytime sleepiness. Methods This is a single case report. A 32 year male wore an Actiwatch Pro and collected sleep diaries for 18 days. On days 1-9, non-blue light blocking eyewear (NBLB) were used all day. On days 10-18, BLB were used all day. Karolinska Sleepiness Scale (KSS) and Stanford Sleepiness Scale (SSS) during morning, afternoon and before sleep were recorded. IBM SPSS v. 29.0.0 is used for descriptive analysis, Pearson correlation and T-test comparison. Results White light exposure was not statistically different from BLB and NBLB. Data measured in minutes. Mean and standard deviation of in-bed duration with NBLB was 477.89±66.17 and with BLB was 518.06±53.06 (p=0.087). Sleep time with NBLB was 431.89±52.05 and with BLB was 471.72±48.49 (p=0.056). Wake After Sleep Onset (WASO) with NBLB was 43.78±18.63 and with BLB 46.33±14.25 (p=0.374). Percent Sleep with NBLB was 90.96±2.83% and with BLB was 91.09±2.29 (p=0.459). KSS scores for morning on NBLB was 1.75±1.035 and 1.00±0 with BLB (p= 0.023), afternoon NBLB 4.13±1.25, BLB 3.67±0.87 (p=0.194), before sleep NBLB 8.5±1.41 and 8.56±0.53 with BLB (p=0.457). SSS scores for morning on NBLB was 1.63±0.744 and 1.00±0 with BLB (p= 0.012), afternoon NBLB 3.38±1.06, BLB 3.56±0.88 (p=0.353), before sleep NBLB 7.00±1.41 and 7.89±0.60 with BLB (p=0.053). There was a strong correlation between white light exposure and increased WASO (Pearson 0.514) and strong negative correlation (Pearson -0.535) between white light exposure and percent of sleep duration. Conclusion Although there were no statistically significant differences between the sleep parameters between NBLB and BLB, we found a strong correlation between sleep time and white light exposure and negative correlation. When using BLB morning alertness was better. Support (if any)