Continuous Light Research Articles

Effect of 460 nm blue light PBM on human MeWo melanoma cells.

Photobiomodulation (PBM) using 460 nm blue light has been shown to have an inhibitory effect on skin cancer cells. In this study, we used a continuous LED light source with a wavelength of 460 nm and designed various combinations of power density (ranging from 6.4 to 25.6 mW) and dose (ranging from 0.96 to 30.72 J/cm2) to conduct treatment experiments on MeWo cells to investigate the effects of blue light on MeWo melanoma cells. We are focusing on cell viability, cytotoxicity, mitochondrial function, oxidative stress, and apoptosis. We found that blue light inhibits these melanoma cells through oxidative stress and DNA damage, and this inhibition intensifies at higher irradiance levels. Although the cells initially attempt to resist the stress induced by the treatment, they eventually undergo apoptosis over time. These findings contribute to understanding melanoma's molecular response to blue light PBM, lay the groundwork for future clinical applications.

Judicious Fluorination of Perovskite Quantum Wells Enables Over 25% Efficiency in Inverted Solar Cells

AbstractThe photovoltaic performance of inverted perovskite solar cells (PSCs) is often hindered by trap‐induced non‐radiative recombination and photochemical degradation occurring at the upper interfaces and the grain boundaries of perovskite films. Herein, ortho‐, meta‐, and para‐isomers of fluorophenylethylammonium iodine (F‐PEAI) organic spacer molecules are evaluated for the construction of perovskite quantum wells (2D or quasi‐2D, PQWs) to encapsulate 3D perovskites. Among the three variants, p‐F‐PEAI leads to the most symmetric charge distribution and the weakest steric hindrance which resulting in reinforced interactions with PbI2 and perovskite, the enhanced out‐of‐plane orientation is confirmed by Grazing incidence wide‐angle X‐ray scattering (GIWAXS) results. Density functional theory and crystal orbital Hamilton population (COHP) calculations further confirm that p‐F‐PEAI engages most strongly with the perovskite structure. Moreover, transmission electron microscopy (TEM) characterization is used to illustrate that p‐F‐PEAI‐assisted 2D PQWs effectively passivate both the grain boundaries and surfaces of perovskites. This configuration facilitates effective surface passivation, improves charge carrier transport, and significantly suppresses non‐radiative recombination. The resultant inverted PSCs achieve an excellent power conversion efficiency (PCE) of 25.03% with a fill factor (FF) of 85.11%. The unencapsulated devices exhibit enhanced long‐term stability under ambient environments and continuous light illumination.

Sustainable scalable solid-state synthesis of highly efficient synergetic 2D/0D micro/nanostructured g-C3N4/CdS photocatalysts for hydrogen production and water purification

Highly efficient synergetic photocatalysts based on graphitic carbon nitride (g-C3N4) and cadmium sulfide (CdS) semiconductors with 2D/0D micro/nanostructure were successfully prepared by easy scalable mechanochemical method and investigated. An in-depth study of electrons' binding energy of semiconductors and their influence on the photocatalytic activity of nanocomposites has been performed. The synthesized materials were applied for the photodegradation of Orange II dye and photocatalytic hydrogen evolution. The obtained experimental results revealed that nanocomposite with 20 wt% of g-C3N4 and 80 wt% of CdS is able to completely decompose Orange II molecules after two hours of visible light irradiation. The mechanism and pathways of photocatalytic reactions have been proposed. The nanocomposite composed of 60 wt% g-C3N4 and 40 wt% CdS, decorated by a platinum (Pt) co-catalyst, demonstrated the peak hydrogen evolution rate (HER) of 2254.54 μmolh−1 g−1 after 4th hour of solar light illumination. This remarkable achievement, with an apparent quantum efficiency (AQE) of 2.0%, occurred on the fourth hour of solar light irradiation. Furthermore, under continuous visible light irradiation, the sample with the same composition is capable of producing hydrogen. The peak HER rate recorded was 246.14 μmolh−1 g−1 (AQE = 0.44%) after 2.5 h, and this remained consistently the same throughout the entire duration of the process.

Variations in photoperiods and their impact on yield, photosynthesis and secondary metabolite production in basil microgreens

BackgroundThe effects of different photoperiods on plant phytochemical synthesis can be improved by adjusting the daily light integral. Photoperiod is one of the most important environmental factors that control growth, plant’s internal rhythm and the synthesis of secondary metabolites. Information about the appropriate standard in terms of photoperiod for growing basil microgreens as one of the most important medicinal plants is limited. In this study, the effects of five different photoperiods, 6 (6 h × 3 cycles), 8 (8 h × 2 cycles), 16, 18, and 24 h day− 1 on the yield, photosynthesis and synthesis of secondary metabolites of three cultivars and one genotype of basil microgreens in floating system were evaluated. The purpose of this research was to determine the feasibility of using permanent light in growing basil microgreens and to create the best balance between beneficial secondary metabolites and performance.ResultsThe results showed that the effects of photoperiod and cultivar on all investigated traits and their interaction on photosynthetic pigments, antioxidant capacity, total phenolic compounds, proline content and net photosynthesis rate were significantly different at the 1% level. The highest levels of vitamin C, flavonoids, anthocyanins, yield and antioxidant potential composite index (APCI) were obtained under the 24-h photoperiod. The highest antioxidant capacity was obtained for the Kapoor cultivar, and the highest total phenolic compound and proline contents were measured for the Ablagh genotype under a 24-h photoperiod. The highest yield (4.36 kg m− 2) and APCI (70.44) were obtained for the Ablagh genotype. The highest nitrate content was obtained with a photoperiod of 18 h for the Kapoor cultivar. The highest net photosynthesis rate was related to the Violeto cultivar under a 24-hour photoperiod (7.89 μmol CO2 m− 2 s− 1). Antioxidant capacity and flavonoids had a positive correlation with phenolic compounds and vitamin C. Yield had a positive correlation with antioxidant capacity, flavonoids, vitamin C, APCI, and proline.ConclusionsUnder continuous light conditions, basil microgreens resistance to light stress by increasing the synthesis of secondary metabolites and the increase of these biochemical compounds made basil microgreens increase their performance along with the increase of these health-promoting compounds. The best balance between antioxidant compounds and performance was achieved in continuous red + blue light. Based on these results, the use of continuous artificial LED lighting, due to the increase in plant biochemical with antioxidant properties and yield, can be a suitable strategy for growing basil microgreens in floating systems.

The effect of aluminum- and silicon-containing enterosorbent on the thymic cellular composition in mice kept under two-week all-night lighting

Background. Continuous lighting contributes to the development of desynchronosis, which is stressful for the body. As a result, the normal functioning of the immune system is disrupted, which in turn can shift the physiological balance towards pathology and endotoxemia. It is relevant to develop innovative drugs based on a sorbent matrix, which can be modified with biologically active molecules that extendedly leave the sorbent surface. At the same time, the sorbent retains the properties of a detoxifier, fixing toxic agents on the surface and removing them from the body, which helps restore the internal environment and normalizes the overall reactivity of the body in extreme conditions.The aim. To study the effect of aluminum- and silicon-containing enterosorbent (based on aluminum oxide and polydimethylsiloxane) on the cellular composition of the thymus and the distribution of thymocytes in the organ according to the cell cycling state in C57Bl/6 mice kept under the all-night lighting.Materials and methods. Animals received sorbent (0.665 g per 1 kg of body weight in 200 μl of distilled water) through an intragastric tube once a day for 14 days against the background of continuous lighting. Intact mice and placebo animals composed control group. We used flow cytometry to assess the percentage of CD3hi and CD3low lymphocytes of the thymus, the CD3low/CD3hi ratio, viability and distribution of cells across according to the cell cycling state.Results. Continuous lighting inhibited the differentiation and maturation of young CD3low lymphocytes into mature forms of CD3hi, reduced the proliferation of thymic epithelial cells, and activated apoptosis of lymphocytes and epithelial cells in the organ. The introduction of the sorbent restored the content and viability of young CD3low lymphocytes and contributed to the preservation of the viability and proliferation of thymic epithelial cells.Conclusion. Using an enterosorbent based on aluminum oxide and polydimethylsiloxane under conditions of continuous lighting helps maintain the functional activity of the thymus, preventing its involution, and is advisable against the background of circadian disruption.

Lead‐Free Perovskites with Photochromism and Reversed Thermochromism for Repeatable Information Writing and Erasing

AbstractRecently, novel optical information writing strategies have been developed based on fluorescent change of halide perovskites generated by light induced structural transformation. However, to date, the repeatable writing and erasing of fluorescent patterns are still a major challenge. Herein, lead‐free Cs3InCl6:Sb3+ perovskite with photochromism and reversed thermochromism is developed for repeatable information writing and erasing. The original Cs3InCl6:Sb3+ perovskite synthesized by a modified hot‐injection method exhibits green photoluminescence (PL), which is caused by recombination of self‐trapped excitons. After treating with ultrasonication and heating, the green PL gradually turns to blue emission, which is related to surficial Cl vacancies that are generated or exposed due to the desorption of surfactants. Under continuous UV light irradiation, due to the photo repairing effect, the blue emission gradually vanishes, the fluorescent color recovers to green. Based on this photochromic effect, fluorescent patterns are drawn by UV exposure with mask. Moreover, the green PL color can again return to blue by heating at 100 °C. Thus, the photochromism‐induced fluorescent patterns can be simply erased based on the reversed thermochromism effect. Therefore, repeatable optical information writing and thermal erasure are demonstrated based on reversible PL change of Cs3InCl6:Sb3+.

Construction of Ternary Heterostructured NaNbO<sub>3</sub>/Bi<sub>2</sub>S<sub>3</sub>/ Ag Nanorods with Synergistic Pyroelectric and Photocatalytic Effects for Enhanced Catalytic Performance

The removal of dyes and pathogens from contaminated water remains a significant challenge. In the present study, NaNbO3 and NaNbO3/Bi2S3 powders were prepared by a simple hydrothermal method, and then the noble metal Ag was successfully deposited on NaNbO3/Bi2S3 by photoreduction to constitute the NaNbO3/Bi2S3/Ag ternary nanorods heterostructure. With continuous visible light irradiation and controlled temperature variation (25-55 °C), the monomeric NaNbO3 could degrade 73.3% of Rhodamine B (RhB) and inactivated 46% of Salmonella while the ternary complex NaNbO3/Bi2S3/Ag showed a higher RhB degradation efficiency of 94.9% as well as an higher sterilization efficiency of 82%. In addition, after four replicate experiments, NaNbO3/Bi2S3/Ag still had a high degradation efficiency. Compared with NaNbO3 monomer, NaNbO3/Bi2S3/Ag possessed stronger catalytic ability. The improvement of catalytic activity could be attributed to the efficient separation of pyroelectric and photocatalytic electrons and holes through the formation of NaNbO3/Bi2S3/Ag heterostructural nanorod. Keywords: Ternary heterostructures; Nanocomposites; Pyroelectricity; RhB solution degradation; Salmonella sterilization

Highly efficient and stable organic solar cells achieved by improving exciton diffusion and splitting through a volatile additive-assisted ternary strategy

The ternary and additive strategy, introducing a third component into a binary blend and add suitable additives, opens a simple and promising avenue to improve the power conversion efficiency (PCE) of organic solar cells (OSCs). This study investigates the optimization of OSCs by introducing volatile additives and a third component, L8-BO-X, which tunes the active layer morphology and improves the performance of the devices. Utilizing various characterization techniques, such as the grazing-incidence wide-angle X-ray scattering (GIWAXS), film-depth-dependent light absorption spectroscopy (FLAS), and the femtosecond-resolved transient absorption (fsTA) spectroscopy, the effects of these adjustment on crystallinity, phase separation, exciton generation, and charge transport in photovoltaic device are explored. The incorporation of the third component and volatile additives results in less anisotropy in molecular orientation and thus faster exciton splitting at the D-A interface, enhanced π-π stacking coherence length and longer exciton lifetime, and eventually an enhanced power conversion efficiency (PCE) of 19.6 % (certified as 19.07 % in the National Institute of Metrology in China) and exceptional photostability, with the devices retaining 82 % efficiency after 1200 hours of continuous light exposure.

A Comparison of the Effects of Continuous Illumination and Day/Night Regimes on PHB Accumulation in Synechocystis Cells.

Poly(3-hydroxybutyrate) (PHB) is a biobased and biodegradable polymer with properties comparable to polypropylene and therefore has the potential to replace conventional plastics. PHB is intracellularly accumulated by prokaryotic organisms. For the cells PHB functions manly as carbon and energy source, but all possible functions of PHB are still not known. Synechocystis (cyanobacteria) accumulates PHB using light as energy and CO2 as carbon source. The main trigger for PHB accumulation in cyanobacteria is nitrogen and phosphorous depletion with simultaneous surplus of carbon and energy. For the above reasons, obtaining knowledge about external factors influencing PHB accumulation is of highest interest. This study compares the effect of continuous light exposure and day/night (16/8 h) cycles on selected physiology parameters of three Synechocystis strains. We show that continuous illumination at moderate light intensities leads to an increased PHB accumulation in Synechocystis salina CCALA 192 (max. 14.2% CDW - cell dry weight) compared to day/night cycles (3.7% CDW). In addition to PHB content, glycogen and cell size increased, while cell density and cell viability decreased. The results offer new approaches for further studies to gain deeper insights into the role of PHB in cyanobacteria to obtain bioplastics in a more sustainable and environmentally friendly way.

Photo-programmable hydrogel iontronics for electrically and chromatically rewritable circuits

Hydrogel-based iontronics is emerging as a promising frontier in healthcare and human-machine interfacing (HMI), offering excellent compatibility with biological systems in terms of electrical, chemical, and mechanical properties. However, conventional hydrogel systems have limitations in dynamically regulating their electrical and optical properties, which restricts their use in adaptive electronics and responsive interfaces. In this study, we present a new hydrogel system with UV photochemistry-induced reversible conductivity, enabling reversible changes in conductivity. Unlike typical photo-responsive hydrogels that revert to their original states upon removal of the light source, the new hydrogel can maintain its activated states without continuous light exposure, facilitating practical applications. By leveraging the photobase triphenylmethane leucohydroxide and photoacid n-nitrobenzaldehyde, we achieve a significant increase in photo-induced conductivity compared to existing photo-ionic hydrogels. Combining the effective photo-induced conductivity and the accompanied photochromatic effect, we demonstrate a full hydrogel-based stylus pad capable of tracking motion and strokes, and a soft calculator keypad with programmable conductivity and imprinted patterns. These advancements underscore the importance of actively controlling localized conductivity and processing light inputs in hydrogels, exhibiting their potential for diverse applications in bioelectronics and HMI.

Photoswitchable Imines Drive Dynamic Covalent Systems to Nonequilibrium Steady States.

Coupling a photochemical reaction to a thermal exchange process can drive the latter to a nonequilibrium steady state (NESS) under photoirradiation. Typically, systems use separate motifs for photoresponse and equilibrium-related processes. Here, we show that photoswitchable imines can fulfill both roles simultaneously, autonomously driving a dynamic covalent system into a NESS under continuous light irradiation. We demonstrate this using transimination reactions, where E-to-Z photoisomerism generates a more kinetically labile species. At the NESS, energy is stored both in the metastable Z-isomer of the imine and in the system's nonequilibrium constitution; when the light is switched off, this stored energy is released as the system reverts to its equilibrium state. The system operates autonomously under continuous light irradiation and exhibits characteristics of a light-driven information ratchet. This is enabled by the dual-role of the imine linkage as both the photochromic and dynamic covalent bond. This work highlights the ability and application of these imines to drive systems to NESSs, thus offering a novel approach in the field of systems chemistry.

Characterization of the tail current of Channelrhodopsin-2 variants

Our study focused on specific ChR2 variants, particularly those with the Step function Opsins (SFO) mutation at the D156-C128 gate. These are widely used in optogenetics due to their heightened sensitivity to light and bi-stable prolonged activation. However, in some ChR2 variants, specifically D156 mutants, a tail current occurs when continuous light exposure is stopped. We specifically examined the D156H-T159S ChR2 variant, which demonstrated a tail current that was somewhat responsive to light and voltage, with a single-channel current of around 9fA, similar to wt-ChR2 as determined by stationary noise analysis. To further investigate, we used nonstationary noise analysis in cell-attached patching mode, which revealed that the tail current's single-channel current falls within the same range as the peak current, albeit with mild contamination from adaptation and desensitization. This finding strongly supports the notion that a portion of the ChR2 molecules open or re-open at the end of illumination, leading to further membrane depolarization.

UVC (254 nm) and Far UVC (222 nm) Irradiation Affects In Vitro Growth of Colletotrichum sp. Isolates and Their Infection of Detached Strawberry Leaves

Conventional ultraviolet C at 254 nm (UVC) and Far UVC at 222 nm (Far UVC) were evaluated as alternatives to fungicides for disease control. Conidia of 13 isolates of strawberry anthracnose pathogens (five Colletotrichum species in two complexes: C. acutatum and C. gloeosporioides) were uniformly dispersed onto agar and irradiated with UVC and Far UVC doses ranging from 52 to 1,248 J·m−2. After 48 h of incubation, a UVC dose of 1,248 J·m−2 and Far UVC doses from 234 to 935 J·m−2 reduced Colletotrichum colony counts to <10 colonies/Petri dish. Cultures exposed to UVC light followed by 4 h of darkness had lower colony counts than cultures incubated under continuous light. This dark incubation period was not required for Far UVC to obtain optimal lethality, indicating Far UVC irradiation can be applied during the day or night and achieve similar fungal lethality. Inoculation of detached leaves of three anthracnose-susceptible strawberry cultivars with conidial suspensions of Colletotrichum spp. revealed that UV irradiation can affect development of anthracnose symptoms. Leaves receiving UVC doses of 312 and 624 J·m−2 or a Far UVC dose of 467 J·m−2 reduced anthracnose infection with little or no plant injury. A UVC dose of 1,248 J·m−2 and Far UVC doses ≥ 467 J·m−2 inflicted varying degrees of plant injury. Disease control intended to reduce the number of fungicidal applications could be developed with moderate doses of UVC and Far UVC irradiation while slowing the evolution of pesticide-resistant strains. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 “No Rights Reserved” license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.

Photothermal-boosted S-scheme heterojunction of α-Fe2O3@NiOx for high-selective reduction of CO2 to CO

Self-heating photothermal catalysis, combining light promotion and thermal activation, offers unique advantages for CO2 conversion. The meticulous design of active sites and light-absorbing materials is crucial for high-performance photothermal catalysts. Herein, a S-Scheme heterostructure composed of NiOx subunits with abundant oxygen vacancies (Vo) bonded with α-Fe2O3 nanoplatelets has been fabricated for solar-driven photothermal catalytic CO2 reduction. Under continuous full-spectrum light irradiation (0.3 W·cm−2), the α-Fe2O3@NiOx hybrids exhibited a CO yield rate of 199.3 μmol∙g−1·h−1 in a gas–solid reaction models with near-unity selectivity. Additionally, the apparent quantum yield for CO production at 420 nm reaches 1.56 %. The prominent activity is attributed to three key factors: (1) The Vo-rich NiOx facilitates the accumulation of photogenerated electrons and activation of chemisorbed CO2. (2) The implemented S-Scheme heterostructures boost interfacial charge-transfer and provide spatially separated catalytic sites for efficient overall CO2 reduction. (3) The substantial photothermal effect of NiOx, which arises from nonradiative exciton recombination, induces local heating of the catalyst, thereby enhancing reaction kinetics. This work provides valuable insights into the utilization of a photothermal-photocatalytic S-Scheme heterojunction system for the photothermal catalytic CO2 reduction.

Nanoscale phase management of the 2D/3D heterostructure toward efficient perovskite solar cells

The stabilization of the formamidinium lead iodide (FAPbI3) structure is pivotal for the development of efficient photovoltaic devices. Employing two-dimensional (2D) layers to passivate the three-dimensional (3D) perovskite is essential for maintaining the α-phase of FAPbI3 and enhancing the power conversion efficiency (PCE) of perovskite solar cells (PSCs). However, the role of bulky ligands in the phase management of 2D perovskites, crucial for the stabilization of FAPbI3, has not yet been elucidated. In this study, we synthesized nanoscale 2D perovskite capping crusts with <n> = 1 and 2 Ruddlesden-Popper (RP) perovskite layers, respectively, which form a type-II 2D/3D heterostructure. This heterostructure stabilizes the α-phase of FAPbI3, and facilitates ultrafast carrier extraction from the 3D perovskite network to transport contact layer. We introduced tri-fluorinated ligands to mitigate defects caused by the halide vacancies and uncoordinated Pb2+ ions, thereby reducing nonradiative carrier recombination and extending carrier lifetime. The films produced were incorporated into PSCs that not only achieved a PCE of 25.39% but also maintained 95% of their initial efficiency after 2000 h of continuous light exposure without encapsulation. These findings underscore the effectiveness of a phase-pure 2D/3D heterostructure-terminated film in inhibiting phase transitions passivating the iodide anion vacancy defects, facilitating the charge carrier extraction, and boosting the performance of optoelectronic devices.

Additive and interface passivation dual synergetic strategy enables reduced voltage loss in wide-bandgap perovskite solar cells

The open-circuit voltage (VOC) loss for wide-bandgap (WBG) perovskite solar cells (PSCs) is a significant obstacle to their further development. Herein, we introduce a dual approach involving mixed potassium thiocyanate and potassium chloride (KSCN+KCl) additives combined with 2-thiophene methylamine iodine (2-ThMAI) post-passivation strategy to mitigate VOC loss in WBG PSCs. In the mixed additives, KSCN can expand the grains and reduce the grain boundary, while KCl can inhibit the migration of halogen ions, effectively preventing phase segregation in WBG perovskites under the combination of both. However, due to the substantial energy level mismatch at the perovskite/electron transport layer (ETL) interface, suppressing phase segregation alone is insufficient to reduce the VOC loss. Therefore, introducing 2-ThMAI interface passivation could uniform spatial distribution of perovskite surface potential, promote energetic alignment at perovskite/electron transport layer interface, and further reduce the VOC loss. With these optimizations, the champion WBG PSCs achieved an enhanced VOC of 1.327 V and a promising power conversion efficiency (PCE) of 19.44 %. Additionally, these modified WBG PSCs retained 94 % of their initial efficiency after 500 hours of continuous light soaking at maximum power point tracking in ambient conditions.

Inositol Restores Appropriate Steroidogenesis in PCOS Ovaries Both In Vitro and In Vivo Experimental Mouse Models.

Androgen excess is a key feature of several clinical phenotypes of polycystic ovary syndrome (PCOS). However, the presence of FSH receptor (FSHR) and aromatase (CYP19A1) activity responses to physiological endocrine stimuli play a critical role in the pathogenesis of PCOS. Preliminary data suggest that myo-Inositol (myo-Ins) and D-Chiro-Inositol (D-Chiro-Ins) may reactivate CYP19A1 activity. We investigated the steroidogenic pathway of Theca (TCs) and Granulosa cells (GCs) in an experimental model of murine PCOS induced in CD1 mice exposed for 10 weeks to a continuous light regimen. The effect of treatment with different combinations of myo-Ins and D-Chiro-Ins on the expression of Fshr, androgenic, and estrogenic enzymes was analyzed by real-time PCR in isolated TCs and GCs and in ovaries isolated from healthy and PCOS mice. Myo-Ins and D-Chiro-Ins, at a ratio of 40:1 at pharmacological and physiological concentrations, positively modulate the steroidogenic activity of TCs and the expression of Cyp19a1 and Fshr in GCs. Moreover, in vivo, inositols (40:1 ratio) significantly increase Cyp19a1 and Fshr. These changes in gene expression are mirrored by modifications in hormone levels in the serum of treated animals. Myo-Ins and D-Chiro-Ins in the 40:1 formula efficiently rescued PCOS features by up-regulating aromatase and FSHR levels while down-regulating androgen excesses produced by TCs.

Ultrastable and efficient slight-interlayer-displacement 2D Dion-Jacobson perovskite solar cells

Stability has been a long-standing concern for solution-processed perovskite photovoltaics and their practical applications. However, stable perovskite materials for photovoltaic remain insufficient to date. Here we demonstrate a series of ultrastable Dion−Jacobson (DJ) perovskites (1,4-cyclohexanedimethanammonium)(methylammonium)n−1PbnI3n+1 (n ≥ 1) for photovoltaic applications. The scalable technology by blade-coated solar cells for the designed DJ perovskites (nominal n = 5) achieves a maximum stabilized power conversion efficiency (PCE) of 19.11% under an environmental atmosphere. Un-encapsulated cells by blade-coated technology retain 92% of their initial efficiencies for over 4000 hours under ~90% relative humidity (RH) aging conditions. More importantly, these cells also exhibit remarkable thermal (85 °C) and operational stability, which shows negligible efficiency loss after exceeding 5000-hour heat treatment or after operation at maximum power point (MPP) exceeding 6000 hours at 45 °C under a 100 mW cm−2 continuous light illumination.

Continuous Blue Light Treatment Enhances the Nutritional Value of Hydroponically Grown Eruca vesicaria L. by Improving Ascorbic Acid Biosynthesis.

This study investigates the effect of continuous blue light (CBL) treatment on quality-related metabolites, focusing on ascorbic acid (AsA) accumulation in hydroponically grown Eruca vesicaria (L.). Plants were subjected to CBL treatment, consisting of 24-h exposure to constant-intensity blue light (48 μmol m-2 s-1) and 12-h exposure to the remaining spectrum (192 μmol m-2 s-1). The activities of key enzymes in AsA biosynthesis and recycling were analyzed, including L-galactono-1,4-lactone dehydrogenase (GalLDh), monodehydroascorbate reductase (MDhAR), dehydroascorbate reductase (DhAR), and ascorbate peroxidase (APX). The results showed a significant increase in AsA accumulation of 65.9% during the "day" and 69.1% during the "night" phases under CBL compared to controls. GalLDh activity increased by 20% during the "day phase" in CBL-treated plants. APX activity also rose significantly under CBL conditions, by 101% during the "day" and 75.6% during the "night". However, this did not affect dehydroascorbic acid levels or the activities of MDhAR and DhAR. These findings highlight the potential of tailored light treatments to enhance the nutraceutical content of horticultural species, offering valuable insights for sustainably improving food quality in controlled-environment agriculture (CEA) systems and understanding the roles of blue light in ascorbic acid biosynthesis.

Solar-Powered Molecular Crystal Motor Based on an Anthracene-Thiazolidinedione Photoisomerization Reaction.

Assembling molecular machines into crystals provides a way to harness their power on large length scales, but the development of a crystal analogue to a molecular motor remains a challenge. The molecule (Z)-5-(anthracen-9-ylmethylene)-3-butylthiazolidine-2,4-dione (C4-ATD) has E and Z isomers with strongly overlapping absorption spectra. This spectroscopic property allows both Z → E and E → Z photoisomerization reactions to be driven by a single light source, and simulations indicate this property can provide a route to robust oscillatory motion. Reprecipitation in an aqueous surfactant enables the growth of single crystal microwires that exhibit continuous mechanical oscillations under a wide range of illumination conditions, including ambient solar irradiation. Molecular crystal motors provide a new approach for transforming continuous light into oscillatory mechanical motion.