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Botrytis cinerea is a necrotrophic fungus characterized mainly by its wide host range of infected plants. The deletion of the white-collar-1 gene (bcwcl1), which encodes for a blue-light receptor/transcription factor, causes a decrease in virulence, particularly when assays are conducted in the presence of light or photocycles. However, despite ample characterization, the extent of the light-modulated transcriptional responses regulated by BcWCL1 remains unknown. In this study, pathogen and pathogen:host RNA-seq analyses, conducted during non-infective in vitro plate growth and when infecting Arabidopsis thaliana leaves, respectively, informed on the global gene expression patterns after a 60 min light pulse on the wild-type B05.10 or ∆bcwcl1 B. cinerea strains. The results revealed a complex fungal photobiology, where the mutant did not react to the light pulse during its interaction with the plant. Indeed, when infecting Arabidopsis, no photoreceptor-encoding genes were upregulated upon the light pulse in the ∆bcwcl1 mutant. Differentially expressed genes (DEGs) in B. cinerea under non-infecting conditions were predominantly related to decreased energy production in response to the light pulse. In contrast, DEGs during infection significantly differ in the B05.10 strain and the ∆bcwcl1 mutant. Upon illumination at 24 h post-infection in planta, a decrease in the B. cinerea virulence-associated transcripts was observed. Accordingly, after a light pulse, biological functions associated with plant defense appear enriched among light-repressed genes in fungus-infected plants. Taken together, our results show the main transcriptomic differences between wild-type B. cinerea B05.10 and ∆bcwcl1 after a 60 min light pulse when growing saprophytically on a Petri dish and necrotrophically over A. thaliana. [ABSTRACT FROM AUTHOR]

Temporally heterogeneous environments is hypothesized to correlate with greater plasticity of plants, which has rarely been supported by direct evidence. To address this issue, we subjected three species from different ranges of habitats to a first round of alternating full light and heavy shading (temporally heterogeneous light experience), constant moderate shading and full light conditions (temporally homogeneous light experiences, control) and a second round of light-gradient treatments. We measured plant performance in a series of morphological, biomass, physiological and biochemical traits at the end of each round. Compared to constant full light experience, temporally heterogeneous light conditions induced immediate active biochemical responses (in the first round) with improved late growth in biomass (during the second round); constant moderate shading experience increased photosynthetic physiological and biomass performances of plants in early response, and decreased their late growth in biomass. The karst endemic species of Kmeria septentrionalis showed greater improvement in late growth of biomass and lower decrease in biochemical performance, due to early heterogeneous experience, compared to the non-karst species of Lithocarpus glaber and the karst adaptable species of Celtis sinensis. Results suggested plants will prefer to produce morphological and physiological responses that are less reversible and more costly in the face of more reliable environmental cues at early stage in spite of decreased future growth potential, but to produce immediate biochemical responses for higher late growth potential when early environmental cues are less reliable, to avoid the loss of high costs and low profits. Typical karst species should be more able to benefit from early temporally heterogeneous experience, due to long-term adaptation to karst habitats of high environmental heterogeneity and low resource availability. [ABSTRACT FROM AUTHOR]

Far UVC light (UVC wavelengths below 235 nm) is a comparatively new modality with significant potential to safely and very efficiently inactivate airborne pathogens in occupied indoor locations. There are now significant accumulations of evidence both in terms of the safety of far‐UVC for direct exposure of occupied indoor locations, and in terms of its efficacy to markedly reduce the levels of active airborne pathogens This article reviews both the safety of far‐UVC, which has a clear mechanistic underpinning, and its efficacy, both in the laboratory and in full‐sized rooms. Highlighted is the paper by Ma et al. in this issue of Photochemistry and Photobiology which addresses the efficacy of far‐UVC light (in this case at 222 nm) against a broad spectrum of common pathogens including SARS‐CoV‐2 and influenza viruses. From their data, and based on our understanding of the largely random nature of UVC‐induced damage within the genome, far UVC would be expected to be effective against the next pandemic virus, if and when it emerges. [ABSTRACT FROM AUTHOR]

To investigate the adaptation strategies of 1-year-old Fraxinus mandshurica and Phellodendron amurense seedlings under low light and to determine their optimal growth light intensities, four light intensity treatments (100%, 75%, 45%, and 15% full light, noted as L100, L75, L45, and L15) were used to observe the growth, photosynthetic characteristics and non-structural carbon (NSC) content of 1-year-old seedlings of both species and their allocation. The results showed that the growth indexes (photosynthetic tissue to non-photosynthetic tissue biomass ratio showed an opposite trend), basic photosynthetic parameters and photosynthetic product indexes of the Fraxinus mandshurica seedlings, except for the ground diameter, were highest under L45 treatment, and some of them were significantly different (P<0. 05) compared with those under L15 and L100 treatments. The growth indexes, basic photosynthetic parameters and photosynthetic product indexes of the Phellodendron amurense seedlings were highest under L100 light intensity, and the differences were significant (P<0. 05) compared with the other three light intensities. The chlorophyll (Chl) indexes of both species decreased with increasing light intensity (Chl a/b increased). In addition, the plasticity of each index of both seedlings was greater in Phellodendron amurense than in Fraxinus mandshurica, and the top three plasticity values of Fraxinus mandshurica seedlings were, in descending order, seedling quality index, root biomass, and Chlb, while those of Phellodendron amurense seedlings were, in descending order, seedling quality index, leaf biomass, and root biomass. In conclusion, 1-year-old Fraxinus mandshurica seedlings were highly shade tolerant with an optimum growth light intensity of 45% full light (L45); 1-year-old Phellodendron amurense seedlings were less shade tolerant with an optimum growth light intensity of 100% full light (L100) and may die with increasing shade time. [ABSTRACT FROM AUTHOR]

A subfield of neuroproteomics, retina proteomics has experienced a transformative growth since its inception due to methodological advances in enabling chemical, biochemical, and molecular biology techniques. This review focuses on mass spectrometry's contributions to facilitate mammalian and avian retina proteomics to catalog and quantify retinal protein expressions, determine their posttranslational modifications, as well as its applications to study the proteome of the retina in the context of biology, health and diseases, and therapy developments. [ABSTRACT FROM AUTHOR]

This review discusses the most recently reported documents available on the chemistry of thiazoles. In addition, it covers the biological impact of different thiazole based compounds. The information mentioned in this review about the different physico‐chemical characters' and synthetic paths of such important heterocyclic system take especial attraction and consideration of the biomedicinal chemists to make combinatorial library and exert more efforts in the search of thiazoles. [ABSTRACT FROM AUTHOR]

The Lesser Pacific Striped Octopus, Octopus chierchiae, is a small iteroparous octopus known to inhabit intertidal regions of the Pacific coast of Central America. Many details about its life history and ecology remain unknown. For apparently rare and delicate animals such as O. chierchiae, non-extractive sampling methods are necessary to study individuals and populations over time. After photographically documenting the physical development of 25 octopuses from hatching, we have concluded that O. chierchiae has individually unique stripe configurations that remain constant throughout their post-hatchling lifetimes. Furthermore, using photographs taken of animals in captivity on different dates over many months, we show that untrained volunteers can accurately identify whether or not a pair of images depicts the same individual octopus. These results demonstrate that laboratory-reared individuals could be identified via photographs taken at different points in their lifetimes, which suggests wild individuals can also be recognized and observed for longitudinal field studies. In addition, our results imply potential for photoidentification and community science to be used as non-extractive, non-intrusive sampling methods for future studies of wild O. chierchiae. [ABSTRACT FROM AUTHOR]

Photosynthetic algae have evolved mechanisms to cope with suboptimal light and CO2 conditions. When light energy exceeds CO2 fixation capacity, Chlamydomonas reinhardtii activates photoprotection, mediated by LHCSR1/3 and PSBS, and the CO2 Concentrating Mechanism (CCM). How light and CO2 signals converge to regulate these processes remains unclear. Here, we show that excess light activates photoprotection- and CCM-related genes by altering intracellular CO2 concentrations and that depletion of CO2 drives these responses, even in total darkness. High CO2 levels, derived from respiration or impaired photosynthetic fixation, repress LHCSR3/CCM genes while stabilizing the LHCSR1 protein. Finally, we show that the CCM regulator CIA5 also regulates photoprotection, controlling LHCSR3 and PSBS transcript accumulation while inhibiting LHCSR1 protein accumulation. This work has allowed us to dissect the effect of CO2 and light on CCM and photoprotection, demonstrating that light often indirectly affects these processes by impacting intracellular CO2 levels. Photosynthetic algae have evolved to survive in suboptimal light and CO2 conditions. Here, the authors show that depletion of CO2 can drive photoprotection and carbon acquisition even in the absence of light, that was previously believed to be indispensable for the activation of these processes. [ABSTRACT FROM AUTHOR]

By combining physiological/biochemical and transcriptional analysis, the inhibition and recovery mechanisms of Phaeodactylum tricornutum in response to extreme high light stress (1300 μmol photons · m−2 · s−1) were elucidated. The population growth was inhibited in the first 24 h and started to recover from 48 h. At 24 h, photoinhibition was exhibited as the changes of PSII photosynthetic parameters and decrease in cellular pigments, corresponding to the downregulation of genes encoding light‐harvesting complex and pigments synthesis. Changes in those photosynthetic parameters and genes were kept until 96 h, indicating that the decrease of light absorption abilities might be one strategy for photoacclimation. In the meanwhile, we observed elevated cellular ROS levels, dead cells proportions, and upregulation of genes encoding antioxidant materials and proteasome pathway at 24 h. Those stress‐related parameters and genes recovered to the controls at 96 h, indicating a stable intracellular environment after photoacclimation. Finally, genes involving carbon metabolisms were upregulated from 24 to 96 h, which ensured the energy supply for keeping high base and nucleotide excision repair abilities, leading to the recovery of cell cycle progression. We concluded that P. tricornutum could overcome photoinhibition by decreasing light‐harvesting abilities, enhancing carbon metabolisms, activating anti‐oxidative functions, and elevating repair abilities. The parameters of light harvesting, carbon metabolisms, and repair processes were responsible for the recovery phase, which could be considered long‐term adaptive strategies for diatoms under high light stress. [ABSTRACT FROM AUTHOR]

Achieving local anaesthesia for various clinical dental applications is a challenge that we encounter in our daily practice. Pre-emptive pulpal laser analgesia (PPLA) treatment strategy could be a promising non-pharmacological modality. Hence, our ex vivo laboratory study is aimed at evaluating the changes in enamel surface morphology when irradiated with various published PPLA protocols using scanning electron microscopy (SEM). To do so, 24 extracted healthy human permanent premolar teeth were collected, and each tooth was divided into equal halves randomised into six groups. The following laser parameter protocols based on published protocols of clinical Er:YAG laser-induced PPLA were randomly assigned for each group: 0.2 W/10 Hz/3 J/cm2 (Group A—100% water spray; Group B—no water); 0.6 W/15 Hz/10 J/cm2 (Group C—100% water spray; Group D—no water); 0.75 W/15 Hz/12 J/cm2 (Group E—100% water spray; Group F—no water); 1 W/20 Hz/17 J/cm2 (Group G—100% water spray; Group H—no water). Each sample was irradiated at an angle of 90° to the dental pulp, with a sweeping speed of 2 mm/s for a 30 s exposure time. Our results have shown, for the first time, no alteration to the mineralised tooth structure when irradiated with the following protocols: 0.2 W/10 Hz/3 J/cm2 with 100% water spray or without water spray with an irradiated area fixed at a 10 mm tip-to-tissue distance, sweeping motion with 2 mm/s speed of movement; average power output of 0.6 W/15 Hz/10 J/cm2, maximum water cooling of 100%, tip-to-tooth distance fixed at 10 mm, 30 s exposure time, sweeping motion with 2 mm/s speed of movement. The authors concluded that the current available proposed PPLA protocols in the literature might cause an alteration to the enamel surface. Hence, future clinical studies are warranted to validate our study's PPLA protocols. [ABSTRACT FROM AUTHOR]

Photodynamic therapy can be useful for the eradication of malignant cells at sites that are accessible to light delivery. There are few adverse effects, with many clinical reports indicating that PDT has curative potential. Patients with minimal disease, where success is more likely, are also sought by those promoting other protocols. New photosensitizing agents that initiate light‐catalyzed reactions continue to be discovered. Reports describing advances in understanding fundamental aspects of photobiology are always of interest. But, implications for treatment of neoplasia and other diseases are not always justified, especially when poorly penetrating wavelengths of light are employed, often at very high light doses. Efficacy is sometimes estimated by protocols that may not accurately measure photokilling. Many reports claiming potential clinical relevance for in vitro observations are based on a limited understanding of the determinants of clinical efficacy. The future of photodynamic therapy depends on an appreciation of what can be accomplished, especially when used with other modalities, but will also depend on the goals and interests of granting agencies, pharmaceutical groups, and clinical personnel. This commentary is intended to provide some thoughts on current research efforts, especially where clinical implications are suggested, hinted at or otherwise implied. [ABSTRACT FROM AUTHOR]

Photodynamic therapy can be useful for the eradication of malignant cells at sites that are accessible to light delivery. There are few adverse effects, with many clinical reports indicating that PDT has curative potential. Patients with minimal disease, where success is more likely, are also sought by those promoting other protocols. New photosensitizing agents that initiate light‐catalyzed reactions continue to be discovered. Reports describing advances in understanding fundamental aspects of photobiology are always of interest. But, implications for treatment of neoplasia and other diseases are not always justified, especially when poorly penetrating wavelengths of light are employed, often at very high light doses. Efficacy is sometimes estimated by protocols that may not accurately measure photokilling. Many reports claiming potential clinical relevance for in vitro observations are based on a limited understanding of the determinants of clinical efficacy. The future of photodynamic therapy depends on an appreciation of what can be accomplished, especially when used with other modalities, but will also depend on the goals and interests of granting agencies, pharmaceutical groups, and clinical personnel. This commentary is intended to provide some thoughts on current research efforts, especially where clinical implications are suggested, hinted at or otherwise implied. [ABSTRACT FROM AUTHOR]

The translation of photodynamic effects into clinical practice is a complex process that involves the pharmacokinetics of photosensitizing agents, light dosimetry and oxygenation levels. But even the 'translation' of basic photobiology into meaningful preclinical information can be challenging. Some thoughts on directions for progress in clinical trials are suggested. [ABSTRACT FROM AUTHOR]

Societal Impact Statement The effective management of light is beneficial for growers of plants in greenhouses, polytunnels and under cloches. The materials and structures used to construct these environments often create light‐limited conditions for crops and change the spectral composition of sunlight they receive. Combining practical measures, drawn from knowledge of plant photobiology, allows growers to monitor, forecast and optimise conditions in their growing environment according to its geographical location and the crop grown. Improved management of light through these measures could be expected to improve food quality and yield, and potentially reduce use of energy, water and pesticides. Summary Horticultural production in greenhouses and in polytunnels expands the viable geographic range of many crop species and extends their productive growing season. These semi‐controlled growing environments buffer natural fluctuations in heat, cold and light and hold potential to improve food security with a low environmental footprint. Over the last decade, technological advances in cladding materials, smart filters, photo‐electric cells for energy production and LED lighting have created opportunities to improve the light environment within these structures. In parallel, there have been large advances in plant photobiology, underpinned by progress in identifying the mechanisms of photomorphogenesis and photoprotection, mediated by plant photoreceptors and their interactions, across regions of the spectrum. However, there remains unexploited potential to synthesise and transfer knowledge from these fields to horticulture, particularly with respect to tailoring the use of sunlight to specific locations and production systems. Here, we systematically explain (1) the value of modelling and monitoring patterns of sunlight to allow for informed design of the growth environment; (2) the means of optimising light conditions through selection of materials and structures; (3) the requirements of different crop plants in terms of the amount and spectral composition of light that will benefit yield and food quality; (4) the potential to combine this knowledge for effective management of the sunlight; and, finally, (5) the additional benefits these actions may bring to growers and society at large, beyond the crops themselves, in terms of water use and energy efficiency.

This article discusses two common misconceptions in the field of photodynamic therapy (PDT). The first misconception involves the use of the MTT assay as a surrogate for the clonogenic assay to assess photokilling. The article argues that only clonogenic assays provide a reliable test for survival. The second misconception involves the use of DCFH as a reagent to test for the formation of reactive oxygen species (ROS). The article suggests that DCFH needs to be present during irradiation, not afterward, and that the assay is relatively insensitive to singlet oxygen. The author recommends using clonogenic assays to report on photokilling and conducting assays for specific ROS to correlate total ROS formation with relative efficacy. [Extracted from the article]

We test a newly developed instrument prototype which utilizes time-resolved chlorophyll-a fluorescence techniques and fluctuating light to characterize Symbiodiniaceae functional traits across seven different coral species under cultivation as part of ongoing restoration efforts in the Florida Keys. While traditional chlorophyll-a fluorescence techniques only provide a handful of algal biometrics, the system and protocol we have developed generates > 1000 dynamic measurements in a short (~11 min) time frame. Resulting ‘high-content’ algal biometric data revealed distinct phenotypes, which broadly corresponded to genus-level Symbiodiniaceae designations determined using quantitative PCR. Next, algal biometric data from Acropora cervicornis (10 genotypes) and A. palmata (5 genotypes) coral fragments was correlated with bleaching response metrics collected after a two month-long exposure to high temperature. A network analysis identified 1973 correlations (Spearman R > 0.5) between algal biometrics and various bleaching response metrics. These identified biomarkers of thermal stress were then utilized to train a predictive model, and when tested against the same A. cervicornis and A. palmata coral fragments, yielded high correlation (R = 0.92) with measured thermal response (reductions in absorbance by chlorophyll-a). When applied to all seven coral species, the model ranked fragments dominated by Cladocopium or Breviolum symbionts as more bleaching susceptible than corals harboring thermally tolerant symbionts (Durusdinium). While direct testing of bleaching predictions on novel genotypes is still needed, our device and modeling pipeline may help broaden the scalability of existing approaches for determining thermal tolerance in reef corals. Our instrument prototype and analytical pipeline aligns with recent coral restoration assessments that call for the development of novel tools for improving scalability of coral restoration programs.

Light is an emerging treatment approach that is being used to treat many diseases and conditions such as pain, inflammation, and wound healing. The light used in dental therapy generally lies in visible and invisible spectral regions. Despite many positive results in the treatment of different conditions, this therapy still faces some skepticism, which has prevented its widespread adoption in clinics. The main reason for this skepticism is the lack of comprehensive information about the molecular, cellular, and tissular mechanisms of action, which underpin the positive effects of phototherapy. However, there is currently promising evidence in support of the use of light therapy across a spectrum of oral hard and soft tissues, as well as in a variety of important dental subspecialties, such as endodontics, periodontics, orthodontics, and maxillofacial surgery. The merging of diagnostic and therapeutic light procedures is also seen as a promising area for future expansion. In the next decade, several light technologies are foreseen as becoming integral parts of modern dentistry practice. [ABSTRACT FROM AUTHOR]

Photosystem II (PSII) of the photosynthetic apparatus in oxygenic organisms contains a catalytic center that performs one of the most important reactions in bioenergetics: light-dependent water oxidation to molecular oxygen. The catalytic center is a Mn4CaO5 cluster consisting of four cations of manganese and one calcium cation linked by oxygen bridges. The authors reported earlier that a structural transition occurs at pH 5.7 in the cluster resulting in changes in manganese cation(s) redox potential and elevation of the Mn‑clus-ter resistance to reducing agents. The discovered effect was examined in a series of investigations that are reviewed in this work. It was found that, at pH 5.7, Fe(II) cations replace not two manganese cations as it happens at pH 6.5 but only one cation; as a result, a chimeric Mn3Fe1 cluster is produced. In the presence of exogenous calcium ions, membrane preparations of PSII with such a chimeric cluster are capable of evolving oxygen in the light (at a rate of approximately 25% of the rate in native PSII). It was found that photoinhibition that greatly depends on the processes of oxidation or reduction at pH 5.7 slows down as compared with pH 6.5. PSII preparations were also more resistant to thermal inactivation at pH 5.7 than at pH 6.5. However, in PSII preparations lacking manganese cations in the oxygen-evolving complex, the rates of photoinhibition at pH 6.5 and 5.7 did not differ. In thylakoid membranes, protonophores that abolish the proton gradient and increase pH in the lumen (where the manganese cluster is located) from 5.7 to 7.0 considerably elevated the rate of PSII photoinhibition. It is assumed that the structural transition in the Mn-cluster at pH 5.7 is involved in the mechanisms of PSII defense against photoinhibition. [ABSTRACT FROM AUTHOR]

The trans-A2B-corrole series was prepared starting with 5-(pentafluorophenyl)dipyrromethene, which was then reacted with respective aryl-substituted aldehyde by Gryko synthesis. It was further characterized by HRMS and electrochemical methods. In addition, we investigated experimental photophysical properties (absorption, emission by steady-state and time-resolved fluorescence) in several solvents and TDDFT calculations, aggregation, photostability and reactive oxygen species generation (ROS), which are relevant when selecting photosensitizers used in photodynamic therapy and many other photo-applications. In addition, we also evaluated the biomolecule-binding properties with CT-DNA and HSA by spectroscopy, viscometry and molecular docking calculations assays. [ABSTRACT FROM AUTHOR]

Symsagittifera roscoffensis is a well-known member of the order Acoela that lives in symbiosis with the algae Tetraselmis convolutae during its adult stage. Its natural habitat is the eastern coast of the Atlantic, where at specific locations thousands of individuals can be found, mostly, lying in large pools on the surface of sand at low tide. As a member of the Acoela it has been thought as a proxy for ancestral bilaterian animals; however, its phylogenetic position remains still debated. In order to understand the basic structural characteristics of the acoel genome, we sequenced and assembled the genome of aposymbiotic species S. roscoffensis. The size of this genome was measured to be in the range of 910-940 Mb. Sequencing of the genome was performed using PacBio Hi-Fi technology. Hi-C and RNA-seq data were also generated to scaffold and annotate it. The resulting assembly is 1.1 Gb large (covering 118% of the estimated genome size) and highly continuous, with N50 scaffold size of 1.04 Mb. The repetitive fraction of the genome is 61%, of which 85% (half of the genome) are LTR retrotransposons. Genome-guided transcriptome assembly identified 34,493 genes, of which 29,351 are protein coding (BUSCO score 97.6%), and 30.2% of genes are spliced leader trans-spliced. The completeness of this genome suggests that it can be used extensively to characterize gene families and conduct accurate phylogenomic reconstructions. [ABSTRACT FROM AUTHOR]

The efficacy of blue light therapy in dermatology relies on numerous clinical studies. The safety remains a topic of controversy, where potentially deleterious effects were derived from in vitro rather than in vivo experiments. The objectives of this work were (1) to highlight the nuances behind "colors" of blue light, light propagation in tissue and the plurality of modes of action; and (2) to rigorously analyze studies on humans reporting both clinical and histological data from skin biopsies with focus on DNA damage, proliferation, apoptosis, oxidative stress, impact on collagen, elastin, immune cells, and pigmentation. We conclude that blue light therapy is safe for human skin. It induces intriguing skin pigmentation, in part mediated by photoreceptor Opsin‐3, which might have a photoprotective effect against ultraviolet irradiation. Future research needs to unravel photochemical reactions and the most effective and safe parameters of blue light in dermatology. [ABSTRACT FROM AUTHOR]

Light-harvesting complexes in natural photosynthetic systems, such as those in purple bacteria, consist of photo-reactive chromophores embedded in densely packed "antenna" systems organized in well-defined nanostructures. In the case of purple bacteria, the chromophore antennas are composed of natural J-aggregates such as bacteriochlorophylls and carotenoids. Inspired by the molecular composition of such biological systems, we create a library of organic materials composed of densely packed J-aggregates in a polymeric matrix, in which the matrix mimics the optical role of a protein scaffold. This library of organic materials shows polaritonic properties which can be tuned from the visible to the infrared by choice of the model molecule. Inspired by the molecular architecture of the light-harvesting complexes of Rhodospirillum molischianum bacteria, we study the light–matter interactions of J-aggregate-based nanorings with similar dimensions to the analogous natural nanoscale architectures. Electromagnetic simulations show that these nanorings of J-aggregates can act as resonators, with subwavelength confinement of light while concentrating the electric field in specific regions. These results open the door to bio-inspired building blocks for metamaterials from visible to infrared in an all-organic platform, while offering a new perspective on light–matter interactions at the nanoscale in densely packed organic matter in biological organisms including photosynthetic organelles. [ABSTRACT FROM AUTHOR]

Time-resolved femtosecond-stimulated Raman spectroscopy (FSRS) provides valuable information on the structural dynamics of biomolecules. However, FSRS has been applied mainly up to the nanoseconds regime and above 700 cm−1, which covers only part of the spectrum of biologically relevant time scales and Raman shifts. Here we report on a broadband (~200–2200 cm−1) dual transient visible absorption (visTA)/FSRS set-up that can accommodate time delays from a few femtoseconds to several hundreds of microseconds after illumination with an actinic pump. The extended time scale and wavenumber range allowed us to monitor the complete excited-state dynamics of the biological chromophore flavin mononucleotide (FMN), both free in solution and embedded in two variants of the bacterial light-oxygen-voltage (LOV) photoreceptor EL222. The observed lifetimes and intermediate states (singlet, triplet, and adduct) are in agreement with previous time-resolved infrared spectroscopy experiments. Importantly, we found evidence for additional dynamical events, particularly upon analysis of the low-frequency Raman region below 1000 cm−1. We show that fs-to-sub-ms visTA/FSRS with a broad wavenumber range is a useful tool to characterize short-lived conformationally excited states in flavoproteins and potentially other light-responsive proteins. [ABSTRACT FROM AUTHOR]

Here we document physiological and molecular attributes of three wheat cultivars (ZM9023, YM158 and FM1228) under low light intensity with advanced technologies, including non-standard quantitative technology and quantitative proteomics technology. We found lower dry matter accumulation of YM158 compared with ZM 9023 and FM1228 under low light intensities due to up-regulation of photosynthetic parameters electron transport rate (ETR), Y(II), Fv/Fm, Chl (a + b) of YM158 and down-regulation of Chl a/b. ETR, Y(II) and Fv/Fm significantly decreased between ZM9023 and FM1228. The ETR between PSII and PSI of YM158 increased, while light use efficiency (LUE) of ZM9023 and FM1228 decreased. We found that YM158 had greater propensity to adapt to low light compared with ZM9023, as the former was able to increase photochemical electron transfer rate, enhance photosystem activity, and increase the light energy under low light. This meant that the YM158 flag leaf has stronger regulatory mechanism under low light environment. Through proteomic analysis, we found LHC protein (LHCB1, LHCB4, LHCA2, LHCA3) for YH158 was significantly up-regulated, while the PSII subunit protein of FM1228 and ZM9023 b559 subunit protein were down-regulated. We also documented enhanced light use efficiency (LUE) due to higher light capture pigment protein complex (LHC), photosystem II (PSII), PSI and cytochrome B6F-related proteins, with dry matter accumulation being positively correlated with Fv/Fm, ETR, and ΦPS(II), and negatively correlated with initial fluorescence F0. We suggest that Fv/Fm, ETR, and ΦPS(II) could be considered in shade tolerance screening to facilitate wheat breeding. [ABSTRACT FROM AUTHOR]

Educational research has sometimes been criticized for its seeming lack of relevance to classroom reality and its subsequent inability to inform pedagogical practices. Such criticism has prompted researchers to consider research methods that may better approximate reality. Among these methods, photo-elicitation interviews (PEI) offer a visual dimension to elicit lived experiences, feelings, and thoughts in real educational contexts, and to enhance researchers' understanding of educational practitioners' and students' experiences in real classrooms and school communities. This review examines the application of PEI to explore educational practitioners' and students' lived experiences and perceptions in educational contexts. Specifically, this paper examines the existing educational studies adopting PEI in order to identify the affordances of the method, the challenges it has presented for researchers in the education field, and critical considerations for researchers who may be planning to use the method. Specifically, this review addresses the following three questions: 1. What has PEI contributed to previous investigations of participants' lived experiences and perceptions in educational contexts? 2. What methodological challenges have previous researchers encountered when utilizing PEI? and 3. How can methodological concerns be addressed when designing and implementing PEI to understand participants' lived experiences and perceptions? We provide an up-to-date critical examination and discussion of PEI to better inform researchers seeking to develop the use of the method in future investigations in the education field. [ABSTRACT FROM AUTHOR]

Siliceous diatom frustules present a huge variety of shapes and nanometric pore patterns. A better understanding of the light modulation by these frustules is required to determine whether or not they might have photobiological roles besides their possible utilization as building blocks in photonic applications. In this study, we propose a novel approach for analyzing the near-field light modulation by small pennate diatom frustules, utilizing the frustule of Gomphonema parvulum as a model. Numerical analysis was carried out for the wave propagation across selected 2D cross-sections in a statistically representative 3D model for the valve based on the finite element frequency domain method. The influences of light wavelength (vacuum wavelengths from 300 to 800 nm) and refractive index changes, as well as structural parameters, on the light modulation were investigated and compared to theoretical predictions when possible. The results showed complex interference patterns resulting from the overlay of different optical phenomena, which can be explained by the presence of a few integrated optical components in the valve. Moreover, studies on the complete frustule in an aqueous medium allow the discussion of its possible photobiological relevance. Furthermore, our results may enable the simple screening of unstudied pennate frustules for photonic applications. [ABSTRACT FROM AUTHOR]

Actinobacteria are known to produce a variety of secondary metabolites with skin-protective properties. This study aimed to investigate the photoprotective and antigenotoxic properties against UVB of extracts obtained from Cutibacterium acnes strains. Bacterial growth was measured spectrophotometrically and the constant maximum growth rate (μ) value to each strain, were calculated. In vitro photoprotection efficacy was evaluated using in vitro indices such as sun protection factor (SPFespectrophotometric) and critical wavelength (λc). UVB-antigenotoxicity was also evaluated using the SOS Chromotest. Correlation analysis was used to examine the relationship between SPFespectrophotometric and extract concentration and the %GI estimates. Among the studied strains, one showed low (6.0 ≤ SPFespectrophotometric ≤ 14.9) and eight showed media (15.0 ≤ SPFespectrophotometric ≤ 29.9) UVB photoprotection efficacy. All of them resulted in broad-spectrum (UVA–UVB) photoprotection (λc > 370 nm). In total, two C. acnes ecotypes with different growth rates were evidenced, but the protective metabolites in the extracts were produced without the influence of growth rate. Photoprotective efficacy depended on the extract concentration and was correlated with antigenotoxicity. We demonstrated that C. acnes extracts can be used as sunscreen ingredients that reduce UVB-induced genotoxicity. [ABSTRACT FROM AUTHOR]

To investigate the effects of high-temperature stress on the chlorophyll fluorescence induction kinetics of peony and to determine indicators for the rapid screening of varieties responding to high temperatures, three four-year-old peony variety, 'Fengdanbai', 'Huhong', and 'Yinhongqiaodui', were selected as materials. The photosynthetic curves (Pn-PAR) and fast chlorophyll fluorescence curves (OJIP curves) of peony leaves were measured at different times under high-temperature stress conditions (40 °C), the changes in the photosynthetic characteristics of different peony varieties under high-temperature stress were analyzed, and the heat tolerance of peony was evaluated. The results showed that 'Huhong' grew well within 16 days, while all of the other varieties showed obvious wilting at 6–9 days. High temperatures damaged the structure and function of the photosystem of peony leaves, indicating that the maximum net photosynthetic rate (Pnmax), apparent quantum efficiency (AQE), maximum photochemical efficiency (Fv/Fm), and photosynthetic performance index (PIABS) all tended to decrease under high-temperature stress, while the rate of closing the PS II reaction center (Mo) and the absorption per reaction center (ABS/RC), the capture (TRo/RC), and the dissipation (Dio/RC) of light energy per reaction center showed an overall increasing trend. The ability to cope with high-temperature stress differed among varieties, and the heat tolerance was determined to be in the descending order of 'Fengdanbai' < 'Yinhongqiaodui' < 'Huhong'. The correlation analysis among the parameters and the analysis of the morphological change patterns in peony leaves concluded that PIABS, Dio/RC, and Mo could be used as indicators of peony tolerance to high-temperature stress. The results of the study can provide a basis for the screening of heat-tolerant peony species and peony heat defense in the Jiangnan area. [ABSTRACT FROM AUTHOR]

The hemiterpene isoprene is a volatile C5 hydrocarbon with industrial applications. It is generated today from fossil resources, but can also be made in biological processes. We have utilized engineered photosynthetic cyanobacteria for direct, light-driven production of bio-isoprene from carbon dioxide, and show that isoprene in a subsequent photochemical step, using either near-UV or simulated or natural solar light, can be dimerized into limonene, paradiprene, and isomeric C10H16 hydrocarbons (monoterpenes) in high yields under photosensitized conditions (above 90% after 44 hours with near-UV and 61% with simulated solar light). The optimal sensitizer in our experiments is di(naphth-1-yl)methanone which we use with a loading of 0.1 mol%. It can also easily be recycled for subsequent photodimerization cycles. The isoprene dimers generated are a mixture of [2 + 2], [4 + 2] and [4 + 4] cycloadducts, and after hydrogenation this mixture is nearly ideal as a drop-in jet fuel. Importantly the photodimerization can be carried out at ambient conditions. However, the high content of hydrogenated [2 + 2] dimers in our isoprene dimer mix lowers the flash point below the threshold (38 °C); yet, these dimers can be converted thermally into [4 + 2] and [4 + 4] dimers. When hydrogenated these monoterpenoids fully satisfy the criteria for drop-in jet fuels with regard to energy density, flashpoint, kinematic viscosity, density, and freezing point. Life-cycle assessment results show a potential to produce the fuel in an environmentally sustainable way. [ABSTRACT FROM AUTHOR]

Exploring the rich coordination chemistry of Ce, here we report two new entries in the emerging category of hydroxamate-based metal–organic frameworks (MOFs). The two Ce-hydroxamate MOFs exhibited different band structures and photoelectrochemical properties based on their respective coordinative environments and overall structures, leading to varied H2 generation performances. [ABSTRACT FROM AUTHOR]

Photosystem II (PSII) of grapevine leaves is easily damaged under heat stress, but no such injury is observed when the leaves are heated in low light. To elucidate the mechanisms, we compared the photosynthetic characteristics of grapevine seedlings under heat treatments (42 °C) for 4 h in the dark or low light (200 μmol m−2 s−1). At 42 °C in the dark, the PSII maximum quantum yield (Fv/Fm) decreased significantly with the increase in time but did not change much in low light. The JIP (chlorophyll a fluorescence rise kinetics) test results showed that low light significantly alleviated the damage to the oxygen evolving complexes (OECs; the K-step was less visible) by heat stress. Further, in the presence of de novo D1 protein synthesis inhibitor chloramphenicol, Fv/Fm did not differ significantly between dark and light treatments under heat stress. The 50% re-reduction (RR50) of P700+ on cessation of far-red illumination was faster after light treatment than that in the dark. After exposure to 25 °C in a low light for 15 min, Y(NO) (the constitutive non-regulatory non-photochemical quenching) treated by heat stress and darkness was higher than that by heat stress and light. Overall, our results suggested that enhanced CEFs around PSI in low light could assist PSII against heat damage by maintaining the rate of PSII repair and inhibiting the non-radiative charge recombination in PSII reaction centers. [ABSTRACT FROM AUTHOR]

Proflavine is an acridine derivative which was discovered as one of the earliest antibacterial agents, and it has been proven to have potential application to fields such as chemotherapy, photobiology and solar-energy conversion. In particular, it is well known that proflavine can bind to DNA with different modes, and this may open addition photochemical-reaction channels in DNA. Herein, the excited-state dynamics of proflavine after intercalation into DNA duplex is studied using femtosecond time-resolved spectroscopy, and compared with that in solution. It is demonstrated that both fluorescence and the triplet excited-state generation of proflavine were quenched after intercalation into DNA, due to ultrafast non-radiative channels. A static-quenching mechanism was identified for the proflavine-DNA complex, in line with the spectroscopy data, and the excited-state deactivation mechanism was proposed. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the effect of light intensity on PSII activity of different Schisandrae chinensis.【Method】The leaves of S. chinensis resources ‘Zaohong’ and ‘Tieling-0601’ were treated with 0, 600, 1200 and 1800 μmol/（m²·s） light.【Result】Strong light damaged the photosynthetic machinery easily. High light inhibited the activity of the PSII donor and recipient sides, which hindered electron transport, accumulated a significant amount of ROS and MDA, and caused membrane peroxidation. K point appeared in both ‘Zaohong’ and ‘Tieling-0601’ under strong light, and relative variable fluorescence intensity at the K-step（VK） and relative variable fluorescence intensity at the J-step（VJ） increased with the increase of light intensity, and VJ point was the highest under a light intensity of 1800 μmol/（m²·s）. VJ of ‘Tieling-0601’was higher than that of ‘Zaohong’in all treatments. Compared with the control, the electron transport efficiency（φO）, quantum yield of electron transport(φEo), number of reaction centers（RC/ABS）, quantum yield of electron transport per unit area（ETO/CSO） and captured light energy per unit area（TRO/CSO） of PSII chlorophyll antenna decreased under strong light treatment. The quantum ratio for heat dissipation(φDo), the light energy absorbed per unit area（ABS/CSO） and the heat dissipation per unit area（DIO/CSO） increased. With the increase of light intensity, the accumulation of malondialdehyde（MDA） in both‘Zaohong’and ‘Tieling-0601’increased, and the MDA accumulation in‘Tieling-0601’was higher than that in ‘Zaohong’. There was a significant difference in anthocyanin accumulation of leaves between ‘Zaohong’ and ‘Tieling-0601’, and ‘Zaohong’ was 3 times higher than ‘Tieling-0601’. 【Conclusion】Different germplasm resources of S. chinensis had different responses to high light, and PSII electron transporter activity was stronger under ‘Zaohong’ high light stress, and the ability to resist high light was stronger. [ABSTRACT FROM AUTHOR]

Background: Proton pump inhibitors (PPIs) are extensively prescribed but may cause photosensitivity and drug-induced lupus erythematosus (DILE), which can be overlooked as the drug may have been taken for years prior to presentation. Methods: We reviewed the clinical and investigation findings of patients diagnosed with PPI-induced photosensitivity, diagnosed through the Scottish Photobiology Service. Results: We report 11 patients with median age of onset 61-years and mean duration of PPI ingestion of 5-years [DILE (n = 6), phototoxicity (n = 3) and drug-induced solar urticaria through a lupus mechanism (n = 2)]. Five had Anti-Ro antibodies (three also ANA positive). Predominantly UVA and visible light photosensitivity was observed on phototesting. Discussion: PPIs are a reversible cause of photosensitivity and DILE. Time to onset from drug initiation to symptoms can be prolonged, so clinicians should have a high index of suspicion in those taking PPIs. Most are diagnosed through clinical assessment and lupus serology, with phototesting indicated if there is diagnostic uncertainty. [ABSTRACT FROM AUTHOR]

Sodium Dodecyl Sulfate (SDS) is an anionic surfactant, extensively used in detergents, household and personal care products, as well as in industrial processes. The present study aimed to disclose the potential toxicological effects of SDS exposure under environmentally relevant concentrations (0, 0.1, 1, 3, and 10 mg L−1) on the physiology and biochemistry (photosynthesis, pigment, and lipid composition, antioxidative systems, and energy balance) of two marine autotrophs: the diatom Phaeodactylum tricornutum and the macroalgae Ulva lactuca. A growth rate (GR) reduction in P. tricornutum was observed with a classic dose-response effect towards the highest applied concentration, while a GR increase occurred in U. lactuca. Regarding photochemistry, the decrease in the fluorescence of the OJIP curves and laser-induced fluorescence allowed a better separation between SDS treatments in U. lactuca compared with P. tricornutum. Although all pigments significantly decreased in U. lactuca at the highest concentrations (except for antheraxanthin), no significant variations occurred in P. tricornutum. On the other hand, changes in fatty acid content were observed in P. tricornutum but not in U. lactuca. In terms of classical biomarker assessment, a dose-effect relationship of individual biomarkers versus SDS dose applied; U. lactuca displayed a higher number of biomarker candidates, including those in distinct metabolic pathways, increasing its usefulness for ecotoxicological applications. By evaluating the potential application of optical and biochemical traits, it was evident that the fatty acid profiles of the different exposure groups are excellent candidates in P. tricornutum, concomitant with the characteristics of this anionic surfactant. On the other hand, the results presented by laser-induced fluorescence and some parameters of PAM fluorometry in U. lactuca may be an advantage in the field, offering non-invasive, fast, easy-to-use, high-throughput screening techniques as excellent tools for ecotoxicology assessment. [ABSTRACT FROM AUTHOR]

Abstract The therapeutic approach to metastatic melanoma has revolutionized the clinical course of this disease. Since 2011, different immunotherapeutic drugs have been approved. Nivolumab is a humanized immunoglobulin IgG4 monoclonal antibody that binds to the PD-1 receptor, blocking its interaction with his ligand PD-L1. The authors present a new case of photosensitivity induced by nivolumab. The photo exposed distribution of the eruption, the sun exposure prior to the beginning of the eruption, and the chronological relationship with the beginning of the treatment are data that have allowed us to confirm the suspected clinical diagnosis.

Artificial Light at Night (ALAN) is one of the most widespread stressors on coastal marine habitats. Despite their sparse use in light pollution studies, light traps are a useful methodology to explore which species are attracted by ALAN. For that purpose, we placed light traps during the day and at night in the shallow subtidal adjacent to three natural sandy shores. Additionally, to determine the origin of the catches, the sediment and the water column were also sampled in both periods by a Van Veen grab and a plankton net, respectively. Our results showed that light traps catches at night were dominated by migrant fauna, mostly amphipod crustaceans emerging from the sediment. Other species that perform diel vertical migrations, such as calanoid copepods, were also attracted. This approach may help to understand which taxa are more susceptible to ALAN in these shallow habitats. • Light traps allow us to explore the effects of artificial light in coastal habitats. • Most of the species attracted by light were emergent fauna and other migrants. • Emergent fauna was mainly represented by amphipod crustaceans, as Bathyporeia. • Diel vertical migration in some species could be disrupted by artificial light. • Light pollution regulations must be promoted, especially in marine protected areas. [ABSTRACT FROM AUTHOR]

The UV radiation in sunlight can damage organisms. A new study reveals that female zebrafish deposit a chemical sunscreen into their eggs to protect their developing embryos, a feat that has been lost in fish species whose embryos never experience sunlight. [ABSTRACT FROM AUTHOR]

Plant leaves are green because they contain the green photosynthetic pigments, chlorophylls a and b. Popular science literature, and sometimes even textbooks, state that the greenness is caused by reflection of green light by chlorophyll. In the present study, we compared the reflectance spectra of green leaves to yellow or white leaves of the same species. Chlorophyll-deficient leaves reflected green light more efficiently than green leaves of the same species, which conclusively refutes the misconception. The data show that the green colour of leaves is caused by preferential absorption of blue and red light by chlorophyll, not by reflection of green light by chlorophyll. The data suggest that the cellulose of the cell walls is the main component that diffusely reflects visible light within plant leaves. [ABSTRACT FROM AUTHOR]

Legal pluralism has lived implications for access to natural resources for different people and identities in society. Current methods for researching the implications of legal pluralism and natural resource access have largely relied on conventional qualitative approaches including in-depth interviews, focus group discussions, and ethnographic immersion. While conventional qualitative methods may reveal structures, processes, and motives, they are ineffective in spatializing and visualizing how access plays out in space and time. This paper proposes drone photo-elicitation as a method that combines the strengths of conventional qualitative methods with drone-based aerial imagery. We argue that a drone photo-elicitation approach advances the methodological toolbox in natural resource research while provoking deeper conversations about access differentiation and how these are spatially reflected. [ABSTRACT FROM AUTHOR]

Background: UVB absorption by 7-dehydrocholesterol (7DHC) in the skin triggers the production of vitamin D and its metabolites, which maintain calcium homeostasis. Detection and measurement of 7DHC in skin using modern liquid chromatography–tandem mass spectrometry (LC–MS/MS) techniques have been lacking, yet there is need for such a technique to provide more information on 7DHC concentration and its UVB responses in human skin. Objectives: To develop and validate a reliable method to measure 7DHC concentration in skin. Methods: Human skin punch biopsies of 5 mm diameter obtained through the Manchester Skin Health Biobank were utilised. 7DHC was extracted with ethyl acetate:methanol 1:1 (v/v) and derivatised using 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD), to allow for improved ionisation of 7DHC through Electrospray Ionisation Mass Spectrometry (ESI–MS). Solid supported liquid extraction (SLE) was also employed to allow the removal of larger lipids from 7DHC and minimise potential matrix effects. Results: The LC–MS/MS assay satisfied International Council for Harmonisation research standards for method validation. Calibration curve was linear with a typical r2 of 0.997, coefficient of variation was 11.1% and 4.32% for inter-assay and intra-assay imprecision, respectively. Lower limit of quantification was 1.6 µg/g and upper limit of quantification was 100 µg/g, SLE recovery of 7DHC was on average 91.4%. Conclusions: We have developed a robust, precise and accurate assay for the detection and quantification of 7DHC in small samples of human skin (0.2 cm2 surface area). This novel method of extraction and quantification will be valuable to future vitamin D photobiology research. [ABSTRACT FROM AUTHOR]