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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. [ABSTRACT FROM AUTHOR]

The inversion asymmetry of polar crystals enables ferroelectric ceramics to possess unique physical properties, among which the anomalous photovoltaic effect drives their potential application in photovoltaic conversion. Semiconducting (1−x) KNbO3−xBaNi.5Hf.5O3−δ (KNBNH, x = 2, 4, 6, 8%) ferroelectric ceramics with enhanced photovoltaic performance were prepared by utilizing conventional solid‐state sintering strategies. In these ceramics, the defect‐induced bandgap intermediate state is derived from the 3d split state of Ni and plays a dominant role in lowering the bandgap of KN. The defective bandgap state induced by Ni in KNBNH promotes its absorption of light and the separation of photogenerated carriers, thus enhancing its photovoltaic response. The KNBNH6 shows a maximum value of 138.7 nA/cm2 for short‐circuit photocurrent density (Jsc) among these ceramics, which is further enhanced to 702.9 nA/cm2 after 30 kV/cm polarization. Structural investigations after polarization indicate that polarization induced lattice distortion in KNBNH6, leading to an increase in the polarity of its cells. This work provides an understanding of defect‐induced bandgap states and high‐field polarization to enhance ferroelectric photovoltaic properties. [ABSTRACT FROM AUTHOR]

Background: Vitiligo was an autoimmune disease and some guidelines for the management of vitiligo encouraged the use of NB‐UVB combination therapies to enhance repigmentation. Objectives: To compare the effectiveness of current NB‐UVB combination regimen at the improvement in repigmentation through a systematic review and network meta‐analysis. Methods: We searched the electronic databases for randomized controlled trials related to NB‐UVB combination therapy for vitiligo till October 2022. STATA15.0 software was applied to carrying out data analysis. Results: A total of 28 eligible studies involving 1194 participants were enrolled in the analysis. The NMA results revealed that compared with NB‐UVB, carboxytherapy [OR = 32.35, 95% CI (1.79, 586.05)], Er: YAG laser+ topical 5% 5‐FU [OR = 10.74, 95% CI (4.05, 28.49)], needling/micro‐needling [OR = 3.42, 95% CI (1.18, 9.88)], betamethasone intramuscular injection [OR = 3.08, 95% CI (1.17, 8.13)], topical tacrolimus [OR = 2.54, 95% CI (1.30, 4.94)], and oral Chinese herbal medicine compound [OR = 2.51, 95% CI (1.40, 4.50)] integrated with NB‐UVB were more efficacious in excellent to complete repigmentation response rate (≥75%). Besides, NB‐UVB+ Er: YAG laser+ topical 5% 5‐FU [OR = 0.17, 95% CI (0.04, 0.67)] and NB‐UVB+ needling/micro‐needling [OR = 0.24, 95% CI (0.06, 0.88)] were less likely evaluated as ineffective repigmentation response (≤25%). Conclusions: All combination therapies ranked higher than NB‐UVB monotherapy in inducing successful repigmentation and avoiding failed treatment in patients with vitiligo. Comprehensive consideration, NB‐UVB+ Er: YAG laser+ topical 5% 5‐FU and NB‐UVB+ needling/microneedling would be the preferred therapeutic approaches. [ABSTRACT FROM AUTHOR]

Third‐order nonlinear optical (NLO) absorption properties and ultra‐fast carrier dynamics of organic 4‐N,N‐dimethylamino‐4'‐N'‐methyl‐stilbazolium tosylate (DAST) at the wavelength of 520 nm are investigated by femtosecond open‐aperture Z‐scan technique and transient absorption spectroscopy, respectively. Z‐scan measurements indicate that DAST solution exhibits ultra‐high nonlinear saturable absorption (SA) responses with a figure of merit of 4.57 × 10−13 esu cm and a saturation strength of 3.20 GW cm−2, far superior to those of the most known 2D SA materials under similar excitations. Transient absorption results reveal that the outstanding SA performances of the solution‐phase DAST are rooted in ultra‐fast ground‐state bleaching based on the Pauli blocking effect. The subsequent excited state carrier relaxation processes are dominated by rapid intraband carrier cooling and defect‐assisted interband Auger recombination. Moreover, high‐quality DAST−polyvinyl alcohol composite films prepared by solution casting exhibit similar ultra‐high SA responses and reliable long‐term stability without any degradation of their SA responses even after exposure to air moisture for 100 days. These findings establish an experimental and theoretical foundation for the development of high‐performance ultra‐fast optoelectronic devices based on organic NLO materials in the future. [ABSTRACT FROM AUTHOR]

A bandgap‐tunable KNbO3 ferroelectric ceramic was prepared by introducing Bi/Co ion. The existence of mixed valence states of Co2+/Co3+ in the system induced the bandgap reduction and its tunable behavior. KNbO3–BiCoO3 solid solutions showed a typical orthogonal perovskite structure and maintained good ferroelectricity (Ps = 15.13 µC/cm2) and high‐field polarization ability. The devices based on the.98KNbO3–.02BiCoO3 sample exhibited an improved short‐circuit photocurrent density (Jsc) of 19.2 nA/cm2 under simulated solar radiation, and this was further enhanced to 79.8 nA/cm2 after a 60‐kV/cm polarizing. The structural analysis of the samples after polarization reveals the effect of ferroelectric polarization on photovoltaic performance. This work provides new insights into the effects of ferroelectric polarization on photovoltaic performance. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are widely explored owing to their excellent nonlinear optical (NLO) properties. However, researchers have mainly focused on designing new structures of MOF crystals to adjust the NLO response while ignoring the influence of the number of metal–ligand coordination bonds on the NLO properties of MOFs. In this study, the influence of the coordination numbers of MOFs on their NLO properties is studied for the first time. Herein, MOFs with different coordination numbers, using trifluoroacetic acid as an auxiliary agent, are synthesized and their NLO properties are tested using the Z‐scan technique. The results reveal that the NLO absorption properties of MOFs with high coordination numbers can be effectively modulated from saturable absorption to reverse saturable absorption by increasing the excitation intensity. First‐principles calculations show that a change in the coordination numbers leads to a change in the charge transfer from metal to ligand, thereby resulting in different NLO responses. The MOFs with a high coordination number have potential applications in novel optical switches or logic gates. These results provide a reference for the precise adjustment of the NLO properties of MOFs. [ABSTRACT FROM AUTHOR]

In the process of exploring ferroelectric semiconductors, a new system of (1−x) KNbO3–xSrFeO3−δ (x = 0.00‐0.20) was successfully synthesized via solid‐state reaction. The crystal structures, ferroelectric, dielectric, optical, and electrical properties were systematically characterized. The orthorhombic phase with Amm2 space group is detected in all the ceramics. In addition, the orthorhombic and tetragonal phases coexist in 0.80KNbO3‐0.20SrFeO3‐δ ceramic. The decrease in oxygen octahedron distortion induces a weak ferroelectric polarization. The existence of long‐range ferroelectric polarization order in all the ceramics is verified and the bandgap of the ceramics can be tuned to ~2.18 eV. The improved short‐circuit photocurrent density (Jsc) and open‐circuit voltage (Voc) of the poled 0.95KNbO3‐0.05SrFeO3−δ ceramic at 30 kV/cm are ~6.90 nA/cm2 and 0.04 V, respectively. The activation energies for electrical conductivity of the grains and grain boundaries from 0.90KN–0.10SF ceramic are 0.67 and 0.77 eV, respectively, which indicate the doubly ionized oxygen vacancies. This work provides a new way to tune the optical bandgap/ferroelectric properties of KNbO3‐based ceramics for potential application in ferroelectric photovoltaic and energy fields. [ABSTRACT FROM AUTHOR]

The AC impedance of SrTiO3, Ca0.9Sr0.1TiO3, Ca0.7Sm0.2TiO3, and Ca0.7Sm0.3Ti0.7Al0.3O3 microwave dielectric ceramics with perovskite structures has been analyzed. The impedance spectroscopy results reveal the electrical properties of this series of samples vary significantly with the ceramic microstructure and electrical homogeneity. The εr values of grains for SrTiO3 and Ca0.9Sr0.1TiO3 ceramics are 193.8 and 138.1, respectively, confirming that dielectric response of the high‐εr microwave ceramics is contributed to the grains, at microwave frequencies. Impedance spectroscopy of Ca0.7Sm0.2TiO3 ceramic illustrates that electrical heterogeneous microstructures include interior grains and grain shells. The secondary phase existing in Ca0.7Sm0.2TiO3 ceramic causes deviation in bulk permittivity, resulting in a higher εr ~ 148 of grains than εr ~ 112 of bulk permittivity, measured at microwave frequencies. Grain and grain‐boundary impedance of Ca0.7Sm0.3Ti0.7Al0.3O3 ceramic cannot be separated completely. The permittivities of grains and grain boundaries in Ca0.7Sm0.3Ti0.7Al0.3O3 ceramic are εg ~ 17.8 and εgb ~ 20.8, and the combination of them is close to εr ~ 40 at microwave frequencies. The LogI−LogU curves of the ceramic system indicate that the conducting mechanism of grains and grain boundaries follows ohmic behavior. [ABSTRACT FROM AUTHOR]

Species in genus Nannochloropsis are promising candidates for both biofuel and biomass production due to their ability to accumulate rich fatty acids and grow fast; however, their sexual reproduction has not been studied. It is clear that the construction of their metabolic pathways, such as that of polyunsaturated fatty acid (PUFA) biosynthesis, and understanding of their biological characteristics, such as nuclear ploidy and reproductive strategy, will certainly facilitate their genetic improvement through gene engineering and mutation and clonal expansion. In this study, the genome of N. oceanica S. Suda et Miyashita was sequenced with the next-generation Illumina GA sequencing technologies. The genome was ∼30 Mb in size, which contained 11,129 protein-encoding genes. Of them, 59.65% were annotated by aligning with those in diverse protein databases, and 29.68% were assigned at least one function described in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Less frequent polymorphic nucleotides (one in 22.06 kb) and the obvious deviation from 1:1 (major:minor, minor ≥10) expectation indicated the nuclear monoploidy of N. oceanica. The lack of the majority of meiosis-specific proteins implied the asexual reproduction of this alga. In combination, the nuclear monoploidy and asexual propagation led us to favor the hypothesis that N. oceanica was a premeiotic or ameiotic alga. In addition, sequence similarity-based searching identified the elongase- and desaturase-encoding genes involved in the biosynthesis of long-chain PUFAs, which provided the genetic basis of its rich content of eicosapentaenoic acid (EPA). The functional genes and their metabolic pathways profiled against its genome sequence will facilitate its integrative investigations. [ABSTRACT FROM AUTHOR]

Background Objectives Materials and methods Results Discussion Conclusion Erectile dysfunction has been associated with leisure sedentary behavior in several epidemiological and observational studies. However, the interpretation of these findings is difficult due to residual confounding or reverse causality.To explore the causal association between leisure sedentary behavior and erectile dysfunction, and to explore the underlying mechanism using Mendelian randomization.In the present study, publicly available large‐scale genome‐wide association studies of leisure sedentary behaviors (television watching, computer use, and driving), erectile dysfunction, sex hormones (total testosterone, bioactive testosterone, estradiol, follicle‐stimulating hormone, luteinizing hormone, prolactin, and sex hormone binding globulin), biomarkers of endothelial function (C reactive protein, E‐selectin, and matrix metalloproteinase 7), and psychiatric symptoms (depression and anxiety) were used to perform two‐sample Mendelian randomization analyses. The inverse variance weighting method was the main method used to estimate the association, and sensitivity analyses were also performed.A greater risk of erectile dysfunction was significantly associated with a higher genetic susceptibility to leisure computer usage (odds ratio = 3.57; 95% confidence interval = 1.78–7.16; p < 0.001). No evidence was obtained to suggest that watching television or driving for leisure increased the risk of erectile dysfunction. No association was found between computer use and depression, anxiety, C reactive protein, E‐selectin, matrix metalloproteinase 7, or other sex hormones, with the exception of follicle‐stimulating hormone levels (odds ratio = 0.29; 95% confidence interval = 0.12–0.69; p = 0.01). No indication of heterogeneity or pleiotropy was identified by sensitivity analysis.Extended computer usage for leisure raised the likelihood of developing erectile dysfunction, which may be associated to lower follicle‐stimulating hormone levels; however, the role of endothelial dysfunction and psychological disorders in the development of erectile dysfunction should not be underestimated. Moderate physical activity may help to correct the dysfunction.The present study offered substantial evidence for a positive causal association between computer use and the risk of erectile dysfunction. However, a definitive causal association needs to be established by further research. [ABSTRACT FROM AUTHOR]

Currently, it is widely reported that the photovoltaic effect in ferroelectric materials can be promoted by the application of a piezoelectric force, an external electric field, and intense light illumination. Here, a semiconducting ferroelectric composition is introduced, (1−x) Ba0.06Bi0.47Na0.47TiO3‐xMgCoO3 (abbreviated as xMgCo, where x = 0.02–0.08), synthesized through Mg/Co ions codoping. This process effectively narrows the optical bandgaps to a spectrum of 1.38–3.06 eV. Notably, the system exhibits a substantial increase in short‐circuit photocurrent density (Jsc), by the synergy of the electric, light, and thermal fields. The Jsc can still be further enhanced by the extra introduction of a force field. Additionally, the Jsc also shows an obvious increase after the high field pre‐poling. The generation of a considerable number of oxygen vacancies due to the Co2+/Co3+ mixed valence state (in a 1:3 ratio) contributes to the reduced optimal bandgap. The integration of Mg2+ ion at the A‐site restrains the loss and sustains robust ferroelectricity (Pr = 24.1 µC cm−2), high polarizability under an electric field, and a significant piezoelectric coefficient (d33 = 102 pC N−1). This study provides a novel perspective on the physical phenomena arising from the synergy of multiple fields in ferroelectric photovoltaic materials. [ABSTRACT FROM AUTHOR]