Photonics represents a low-hanging fruit and a highly lucrative industry on the global stage, with applications spanning healthcare and biophotonics, energy and environmental photonics, agriculture and food systems, quantum photonics, telecommunications and data communications, among many other sectors. Despite this breadth of opportunity, the availability of structured biophotonics courses and programs remains limited, largely due to the inherently multidisciplinary nature of the field. Compounding this challenge, many schools, particularly in developing countries, lack adequate science laboratories, especially at the secondary level, thereby depriving learners of the practical exposure necessary to grasp fundamental theoretical concepts meaningfully. These gaps underscore the need for innovative and creative approaches to education and capacity development. Initiatives such as job-shadowing opportunities, outreach activities, summer schools, and diverse forms of online learning are therefore essential in widening access and building foundational skills. Introducing photonics, optics, and biophotonics at the high-school and undergraduate levels would significantly strengthen the talent pipeline, cultivating scarce and highly sought-after skills. Against this backdrop, this paper highlights the importance of targeted strategies that advance biophotonics education and capacity building as a catalyst for sectoral growth.
Nearly all triplet-mediated near-infrared (NIR, over 800 nm) photon upconversion materials have traditionally relied on tetracene derivatives as surface ligands or annihilators. However, the inherent limitations of these compounds, such as poor stability and limited energy level tunability, have significantly impeded the development of NIR-excitable triplet-sensitized photon upconversion materials. In this work, we introduce a distyryl-substituted BODIPY (DS-BDP) derivative that exhibits exceptional stability and spectral tunability, enabling it to function dually as both a surface ligand and an annihilator in quantum dot-based photon upconversion with color-tunable emission under 1064 nm excitation. The incorporation of dicarboxylic acid anchoring groups not only enhances ligand exchange density and facilitates efficient triplet exciton transfer from quantum dots to surface ligands but also effectively suppresses excited-state energy losses caused by ligand conformational relaxation. This ensures high upconversion efficiency in NIR-II-excitable quantum dot-based upconversion materials, even at low surface ligand coverage. Our findings overcome the long-standing limitations associated with tetracene derivatives in photon upconversion and establish a robust material platform with excellent performance and stability for applications in nanophotonics, biophotonics, and photochemistry.
Holographic imaging in microscopy enables label-free quantitative information of biological specimens and has found applications across a wide range of biomedical studies, from cell morphology to particle dynamics; yet its widespread adoption is often limited by the lack of accessible and standardized analysis software. We present HoloBio, an open-source, Python-based graphical user interface developed to address this issue. This software offers two primary operational modes: a Real-Time mode that enables live processing of holograms at video frame rates, and an Offline mode designed for post-processing previously recorded holograms. HoloBio is compatible with holograms recorded using both lens-based and lensless systems, supporting off-axis architectures in telecentric and non-telecentric configurations, as well as slightly off-axis and in-line optical setups. The software incorporates tools for cell tracking, phase profiling, thickness estimation, and morphological analysis, including cell counting and object area quantification. HoloBio is designed to be accessible for users without coding expertise, offering a reproducible, high-throughput environment tailored for researchers in biology, biophotonics, and biomedical imaging.
This study evaluated the short-term biomechanical response of wound tissue following low-level laser therapy (LLLT) by examining changes in skin stiffness, a surrogate biomechanical indicator of short-term tissue response, across different limb regions. A 660 nm LLLT protocol was applied to wound sites. Skin stiffness was quantified using optical coherence tomography (OCT) combined with an air-jet indentation system, enabling non-contact measurement of tissue deformation. For accurate layer-specific assessment, a U-Net-based model was employed to automate OCT image segmentation. The automated segmentation by the U-Net model achieved a segmentation accuracy of 92%, facilitated precise segmentation of skin layers. LLLT significantly reduced skin stiffness after treatment, indicating an acute modulation of tissue compliance. Short-duration LLLT reduces skin stiffness immediately post-treatment, indicating its potential as a non-invasive intervention to modulate the biomechanical environment of wounds. ClinicalTrials.gov identifier: NCT07177274.
Transfusion-related acute lung injury (TRALI) is a severe complication of blood transfusion, but its molecular mechanisms remain poorly understood. This study aimed to investigate the role of Toll-like receptor 4 (TLR4) and its downstream signaling cascade in the pathogenesis of TRALI. Lipopolysaccharide (LPS)-treated PAEC cells and BALB/c mice were used as a model of TRALI. Relative mRNA expression was evaluated via quantitative RT-PCR. Protein abundance in cells/tissues and cell culture supernatant/serum was detected using western blot and ELISA, respectively. Lung tissue injury was evaluated by hematoxylin and eosin staining, and protein expression in lung tissues was analyzed by immunohistochemistry. Expressions of TLR2, TLR4 and myeloid differentiation 2 (MD-2) were significantly elevated in the cellular TRALI model and accompanied by an increase in c-Jun, c-Fos, and P65 phosphorylation and increased expression and secretion of IL-1β, IL-6, IL-8, and TNF-α. The TLR4 inhibitor TAK-242 or MD-2 siRNAs effectively suppressed the molecular alterations induced by LPS in the cellular TRALI model. TAK-242 significantly reduced mortality and lung tissue injury in the TRALI mouse model, decreased TLR2, TLR4 and MD-2 expression, inhibited c-Jun, c-Fos, and p65 phosphorylation, and downregulated IL-1β, IL-6, IL-8, and TNF-α expression. In this animal model of TRALI, the highly expressed TLR4/MD-2 complex promotes the pathogenesis of TRALI through the activation of the activator protein-1(AP-1) and nuclear factor-κB (NF-κB) signaling pathways and the release of inflammatory mediators. One limitation is the positive study in rodent model but not in humans.
Endohedral metallofullerenes Gd2@C80 and Gd3@C80 are typical redox-active gadolinium-based metallofullerenes with potential applications in molecular magnetic materials. However, their neutral forms suffer from intrinsic instability, which severely limits further applications. Herein, we perform systematic theoretical investigations to explore the regulating effects of endohedral and on-cage boron doping on the stability and magnetic properties of Gd2@C80 and Gd3@C80 and on the uncommon B(I) in Gd2B@C80. For dimetallofullerene Gd2@C80, it is discovered that endohedral doping leads to a boron atom that exists in an unusual +1 oxidation state, which has a similar electronic structure to monovalent borylenes. Broken-symmetry density functional theory (BS-DFT) calculations reveal a large magnetic coupling constant of J = 191 cm-1 for Gd2B@C80. For trimetallofullerene Gd3@C80, on-cage boron doping achieves dual effects of stabilization and magnetic induction. Single boron atom substitution eliminates the odd electron distribution on the carbon cage and doubles the HOMO-LUMO gap, while double boron atom substitution triggers the formation of a 3c-1e bond, rarely observed in metallofullerenes. A magnetic coupling constant of J = 146 cm-1 is induced in Gd3@C78B2 as calculated by BS-DFT. Our findings demonstrate that endo/on-cage boron doping is an effective strategy to stabilize redox-active Gd-based metallofullerenes and engineer strong magnetic coupling. The discovery of the 3c-1e bond in trimetallofullerenes opens up new possibilities for the design and construction of diverse high-performance molecular magnetic materials.
To compare the efficacy and safety of intense pulsed light (IPL) versus diode laser (DL) for female axillary hair removal in a randomized split-body trial. Women with Fitzpatrick skin types I-IV received IPL (690-nm filter) and DL (810 nm) on contralateral axillae with randomized side assignment. Four monthly sessions were performed. The primary outcome was hair count in a standardized 4-cm² area. Secondary outcomes included hair shaft thickness, pain intensity (numeric rating scale), participant satisfaction, evaluator-rated improvement (modified GAIS), quality of life (WHOQOL-bref), and adverse events. Participants and outcome assessors were blinded to side allocation. Forty-eight participants initiated treatment; 36 completed all sessions and 28 attended the 4-week post-treatment assessment (S4). Hair counts and hair shaft thickness decreased significantly over time with both modalities. At S4 (primary endpoint), the intention-to-treat analysis showed no statistically significant between-modality difference in hair counts; at 30-week (around 7 months) follow-up, DL showed more favorable objective outcomes (lower hair counts and thinner residual shafts). Pain scores were consistently higher with DL. Adverse-event profiles differed: erythema was more frequent with IPL, whereas perifollicular edema and carbonization were more frequent with DL; events were transient and required no medical intervention. Exploratory stratification by Fitzpatrick skin type showed no consistent pattern of increased adverse events in higher skin types. Satisfaction favored DL, while WHOQOL-bref scores did not change significantly. IPL and DL were both safe and effective for axillary hair removal in women with Fitzpatrick skin types I-IV. DL yielded more favorable longer-term objective outcomes but greater discomfort and transient procedure-related adverse effects. Trial registration: NCT06179186, 23 December 2023.
As primary sites for oxygen consumption and energy production via oxidative phosphorylation (OXPHOS), mitochondria play a central role in the regulation of bioenergetics and generation of key metabolic intermediates for myogenic cell growth. Common methods to study mitochondria and their metabolism typically rely on population-level analyses, which can mask potential differences in individual cells. In this study, we used various imaging approaches to investigate the interplay between intracellular oxygenation, mitochondrial metabolism and dynamics in a model of myogenic differentiation. Fluorescence imaging of intracellular oxygen revealed that myogenic differentiation is accompanied by progressive shifts in intracellular oxygenation that depend upon and reflect changes in mitochondrial metabolism (i.e., higher oxygen consumption and adenosine triphosphate (ATP) production). By measuring intracellular oxygenation, we showed that mitochondrial metabolism reduces oxygen availability in the cytosol and the nucleus. Real-time redox imaging at the single-cell level further highlighted substantial metabolic heterogeneity and a shift toward OXPHOS as differentiation progressed. Morphological analyses revealed that during myogenic differentiation, mitochondria increase in size while becoming less mobile and overlapping less with microtubules. Overall, this study illustrates the value of combining complementary imaging approaches to provide a comprehensive single-cell perspective on mitochondrial metabolism, remodeling and spatial organization during myogenesis.
Genitourinary syndrome of menopause (GSM) is a chronic, oestrogen-deficient condition that is frequently underdiagnosed and undertreated. Although low-dose vaginal estriol improves epithelial trophism and microbial balance, a substantial proportion of women report persistent symptoms. High-quality randomised evidence evaluating combined therapeutic strategies remains scarce. Energy-based modalities, including the erbium:YAG (Er:YAG) laser (λ=2940 nm), have been proposed as adjunctive treatments. This trial aims to assess the efficacy of Er:YAG laser therapy combined with vaginal estriol compared with estriol alone in postmenopausal women with GSM. This is a single-centre, randomised, double-blind, controlled clinical trial. Postmenopausal women aged 45-70 years with vaginal pH ≥5.0 and at least one moderate GSM symptom (Visual Analogue Scale ≥4) will be eligible. Exclusion criteria include current systemic or local hormone therapy, previous vaginal energy-based treatment, abnormal cervical cytology and body mass index ≥35 kg/m2. All participants will receive vaginal estriol cream (0.5 mg per dose) daily for 14 days, followed by twice-weekly administration for 16 weeks. Participants will be randomised (1:1) to receive either estriol plus sham Er:YAG laser or estriol plus active Er:YAG laser. Three laser sessions will be delivered at approximately 4-week intervals. Assessments will occur at baseline, monthly during treatment and 4 months after the final session. The primary outcome is the Vulvovaginal Health Index, with the primary endpoint defined as the change from baseline to 4 months post-treatment, reflecting sustained effect. Secondary outcomes include GSM symptom severity, vaginal microbiome composition (16S rRNA sequencing), quality of life (Menopause Rating Scale) and sexual function (Female Sexual Function Index). Data will be analysed using repeated-measures analysis of variance or appropriate non-parametric tests, with significance set at p<0.05. Ethical approval has been obtained from the Human Research Ethics Committee of UNINOVE. Written informed consent will be obtained. Findings will be disseminated via peer-reviewed journals and scientific meetings. NCT06873971.
This study provides a large-scale clinical validation of a non-invasive method to characterize the mechanical properties of tumoral and non-tumoral human skin, aiding dermatological diagnosis and establishing a database for future research. The non-contact UNDERSKIN device employs Fourier transform calculations to analyze surface wave dispersion generated by a focused airflow, via a skin-specific inversion model combined with a viscoelastic model. This digital palpation technology provides detailed insight into subsurface particle motion, revealing new mechanical responses of basal cell carcinomas (BCC). Conducted ex vivo on over 160 BCC and 40 healthy skin specimens, the results quantify the viscoelastic behavior of each skin layer. Although dermatologists can assess tissue firmness through palpation, they currently cannot objectively quantify it or determine its origins. This technique provides that missing quantification, linking tactile perception to specific biomechanical properties. By measuring where firmness originates within skin layers, this work offers valuable support for improving diagnosis, prognosis, treatment planning, surgical decisions, and the advancement of teledermatology applications.
Molecular photoswitches capable of controlled pH changes are often limited in a critical application, biological systems, by poor aqueous solubility, which hinders their ability to generate large and sustained pH shifts. Herein, we report the synthesis and photophysical characterization of a highly water-soluble, photoswitchable diarylethene base that modulates pH through light-controlled changes in the pKa of an N-heterocyclic imine (NHI) moiety. Using experimentally determined pKa values, we developed and validated a model showing that this NHI-diarylethene exhibits photoacidic behavior over a wide range of pH 6-11 and photobasic behavior over the range pH 3-6, making it the first photoswitch reported to demonstrate dual functionality and to operate in the basic pH regime. By alternating UV and visible light irradiation, this NHI-diarylethene switch achieved a change of >1.7 pH units and was reversibly cycled in both buffered and unbuffered aqueous solutions. We applied this photoswitch to reversibly control the assembly of the pH-responsive, cationic reflectin protein, which shows promise for biophotonic applications. This photoswitch is a powerful tool for bioinspired systems that operate in aqueous environments, where precise, sustained, and reversible pH control is essential for mimicking dynamic biological functions such as assembly, signaling, and responsiveness.
Raman spectrometry, with its capability to noninvasively characterize the molecular composition of microscopic subcellular volumes, including single organelles in live cells, has revolutionized cell biology research. Being introduced as a label-free approach for biochemical imaging, the practical applications of Raman spectrometry still often include the fluorescence probes for the localization of organelles and other subcellular domains of interest. Aiming to overcome this limitation, we report on the development of an artificial intelligence/machine learning approach for true label-free identification of different types of subcellular structures. Here, we explore the application of machine learning (ML) to learn the relationship between a set of biochemical parameters in single organelles of live cells. The biochemical parameters are extracted by Ramanomics, an optical Omics technology, from Raman spectra of single organelles of live cells of different cell lines. Several classification algorithms, such as neural networks, Random Forests, support vector machines, logistic regression, and Gaussian process classification, are evaluated. We report the performance of the best classifier, a shallow neural network, to classify the type of organelle using the biochemical parameters. Evaluation is done using k-fold cross-validation (k = 10), and the final output classification is compared against the ground truth. The k-fold cross-validation shows that the NN-based classifier has significant accuracy (∼90%) to distinguish between different organelles using Ramanomics measurements. Our approach allows us to identify the precise location of separate organelles by local Raman measurement without labeling.
Photoacoustic microscopy (PAM) provides label-free and high-resolution imaging capabilities. However, its optical absorption-based contrast differs fundamentally from hematoxylin and eosin (H&E) staining, hindering integration into standard pathological interpretation workflows and limiting clinical translation and adoption. To address this limitation, we employ a low-cost, radiation-free 532 nm optical-resolution PAM (OR-PAM) system to construct a specimen-level cross-modal dataset for colorectal cancer. Based on this dataset, we propose a virtual H&E staining generation workflow that eliminates pixel-level alignment, enabling conversion of single-wavelength OR-PAM image data into H&E-style images with interpretable tissue structures. Quantitative evaluations demonstrate that our method's virtual sections outperform state-of-the-art unsupervised image-to-image translation models in overall structural fidelity, visual authenticity, and distribution consistency across key assessment metrics. This indicates that virtual staining can act as an efficient visualization layer for preliminary pathological assessment, offering a potential translational pathway for PAM in colorectal cancer clinical imaging.
Bloodstream infections are associated with considerable morbidity and mortality, necessitating timely and accurate antimicrobial susceptibility testing (AST) to guide appropriate therapy. Current diagnostic methods primarily rely on culture-based AST, which is time-consuming, or on genotypic approaches that lack phenotypic relevance. We present the RamanBioAssay (RBA) platform, a novel diagnostic tool integrating dielectrophoretic on-chip bacterial enrichment with label-free Raman spectroscopy, to enable rapid phenotypic AST and simultaneous bacterial identification (ID). The RBA platform delivers AST results within 3.5 h from a positive blood culture, substantially reducing the diagnostic turnaround time compared to standard culture-based techniques. The RBA platform demonstrated high concordance with conventional AST using quality control strains: 94.4% and 100% for E. coli treated with ciprofloxacin and S. aureus treated with oxacillin in medium controls, 91.7% and 97.2% in artificial blood cultures, respectively. For proof-of-concept evaluation, six patient blood cultures were analyzed, yielding concordance rates of 91.7% and 83.3% for E. coli treated with ciprofloxacin and S. aureus treated with oxacillin, respectively (1/6 samples showed a S/R mismatch, 1/6 samples was nonconclusive). The mean diagnostic turnaround time for clinical samples was 3 h and 6 min (±24 min). Additionally, the family level classification of E. coli and S. aureus, shown exemplary in medium controls, was achieved with 97.2% accuracy. These findings highlight the RBA platform as a promising tool for rapid phenotypic AST combined with bacterial ID, providing comprehensive and clinically actionable results significantly faster than conventional methods.
Previous studies have shown that SNF1-related protein kinase 2 (SnRK2s) phosphorylate FREE1 (FYVE domain protein required for endosomal sorting 1) at serine residue S530S533 and MUT9-like kinase (MLKs) phosphorylate FREE1 at serine residue S582 in response to ABA signaling. This study aims to elucidate the synergistic regulation of FREE1 protein phosphorylation and ABA signaling by SnRK2s and MLKs kinases. Using bimolecular fluorescence complementation (BiFC) and transient expression, we found that SnRK2s associate with MLK4 and show significant co-localization in the nucleus. The enhanced ABA sensitivity observed in the snrk2.2/2.3/mlk134 quintuple mutant relative to the snrk2.2/2.3 background points to a genetic interaction where MLKs are epistatic to SnRK2s, revealing a hierarchical relationship in this regulatory pathway. Furthermore, MLKs phosphorylated FREE1 in the snrk2.2/2.3 mutant indicated that SnRK2s and MLKs regulate FREE1 phosphorylation independently. Additionally, compared with overexpressing FREE1(S530D/S533D/S582A), overexpression of the FREE1(S530A/S533A/S582D) variant resulted in enhanced nuclear localization and rescued the ABA hyposensitivity in free1-ctmut and mlks mutant backgrounds. Together, our findings unveil a novel regulatory layer of ABA signaling and establish a framework for understanding the synergistic action of SnRK2 and MLK kinases.
Mitochondrial structural remodeling is closely coupled to intracellular Ca2+ signaling, and precise spatiotemporal control of this process is critical for understanding mitochondrial physiology. Here, we report an optical approach based on femtoSOC (femtosecond laser-controlled store-operated calcium channel) activation to induce localized Ca2+ influx and trigger region-specific mitochondrial growth in living cells. The Ca2+-regulated mitochondrial growth relies on MCU-dependent Ca2+ uptake and OPA1-mediated fusion but is not primarily mediated by the AMPK/CaMKKβ pathway. This study provides a minimally invasive strategy for precise optical control of mitochondrial dynamics and reveals an AMPK-distinct pathway linking localized Ca2+ signaling to mitochondrial structural remodeling.
Moiré superlattices have emerged as a highly tunable platform for exploring correlated bosonic states, such as the recently discovered dipole ladder arising from strong on-site exciton-exciton interactions. Although spectroscopic signatures of these dipole ladders are established, their influence on exciton transport has remained unknown. Here, we employ hyperspectral transient photoluminescence microscopy to directly visualize exciton dynamics in a WS2/WSe2 moiré superlattice and demonstrate that dipole ladder mediates highly efficient exciton drift. At high excitation densities, the formation of a transient dipolar ladder generates a steep internal potential gradient. This gradient triggers a transition from localized, diffusion-limited transport (with a diffusion coefficient of D ≈ 0.01 cm2 s-1) to rapid, drift-dominated flow, yielding an equivalent diffusion coefficient of 0.75 cm2 s-1. These results establish dipole ladders as an interaction-driven mechanism for controlling exciton flow in moiré superlattices.
While light scattering is widely utilized in optical metrology and measurement, it has long been regarded as detrimental in laser-material processing. Here, we report an interferometric scattering effect that overturns this conventional view by resolving the six-decade challenge of axial resolution in optical manufacturing. This breakthrough elevates the axial resolution from micrometers, e.g., ~2 µm in transparent solids slicing, to the sub-10 nm level. The underlying mechanism involves the controlled sequential generation of nano-scatterers through interference between the incident laser and deliberately seeded scattering centers. Based on this phenomenon, we developed an interferometric scattering-based optical tomoslicing technology (i-SOT), achieving kerf widths as narrow as 7 nm under an industrial standard efficiency of up to 400 mm²/s. This unprecedented axial resolution enables nearly lossless laser wafering from ingots-reducing mass loss from ~30% to below 1% - with transformative potential for manufacturing laser crystals, photovoltaics, and microelectronic chips.
This study investigated balance control during the half squat by analyzing the relationship between the center of mass (CoM) and the center of pressure (CoP) in five experienced male weightlifters performing segmented squats at five load levels (20-80% 1 RM) across four Power-Based Training (PBT) exercises. The area of the 95% confidence ellipse was quantified using the Vicon motion capture system in conjunction with AMTI force plates. Given the small sample size (n = 5), a dual inference approach was implemented-frequentist repeated-measures analysis of variance (ANOVA) complemented by a unified adaptive Bayesian hierarchical model-to mitigate Type II error in low-power scenarios. Regarding the movement phase, a marked effect on center of pressure (CoP) stability was observed, as evidenced by both statistical approaches (frequentist: F(1.65, 6.59) = 19.44, p = 0.002, ηp2 = 0.829; Bayesian: P(β_phase < 0) > 0.999). Although external load did not reach statistical significance in the frequentist analysis (p = 0.177, achieved power = 0.27), the Bayesian model provided moderate evidence of a positive impact (β_load = 0.059, 95% HDI [0.005, 0.115], p = 0.981). The area of the center of mass (CoM) ellipse showed no effects of interest. Limb asymmetries were significant and consistent throughout the experiment (frequentist: 48.01 ± 30.13%; Bayesian: 69.48%, 95% HDI [55.86%, 81.44%], P(AI > 20%) = 1.000) and were not modulated by the experimental condition. CoP-CoM coupling was stronger in the mediolateral direction than in the anteroposterior direction. The findings reveal that phase is the primary factor in postural stability, exerting a modest positive influence discernible only through low-powered probabilistic inference, and that the dual framework strengthens inferential robustness in small-sample biomechanical studies. Confirmatory studies with larger samples are recommended.
Photodynamic therapy (PDT) is a minimally invasive treatment that combines a photosensitizer, light, and oxygen to induce localized oxidative stress, resulting in tumor cell death, vascular damage, and immune modulation. This review aimed to summarize the effects of PDT on tumor progression in in vivo models of head and neck cancer. A systematic search was performed across PubMed/MEDLINE, Embase, Scopus, SciELO, and LILACS for studies published between 2015 and 2026, following PRISMA-ScR guidelines and the PICO framework. Eligible studies included animal models with head and neck tumors treated with PDT using non-conjugated photosensitizers. Extracted outcomes included tumor growth, survival rates, histological and molecular changes, immune activation, and adverse effects. Quality assessment was achieved by SYRCLE tools. Preliminary analysis indicates that PDT with different photosensitizers can reduce tumor growth, prolong survival, increase tumor cell death, decrease proliferation and angiogenesis, induce reactive oxygen species production, and modulate immune responses in preclinical models, without apparent toxicity. Despite these promising results, methodological heterogeneity and insufficient dosimetric reporting limit reproducibility. Overall, these findings highlight the therapeutic potential of PDT with different photosensitizers in head and neck preclinical studies and underscore the need for standardized protocols to improve reproducibility and support clinical translation.