Search Results (457)

Air–sea interactions play a pivotal role in shaping cyclone development and evolution. In this context, this study investigates the role of ocean optical properties and solar radiation penetration in modulating subsurface heat content and their subsequent influence on the intensity of Mediterranean cyclones. Using a regional coupled ocean–wave–atmosphere model, we conducted sensitivity experiments for Storm Daniel (2023) comparing two solar radiation penetration schemes in the ocean model component: one with a constant light attenuation depth and another with chlorophyll-dependent attenuation based on satellite estimates. Results show that the chlorophyll-driven radiative heating scheme consistently produces warmer sea surface temperatures (SSTs) prior to cyclone onset, leading to stronger cyclones characterized by deeper minimum mean sea-level pressure, intensified convective activity, and increased rainfall. However, post-storm SST cooling is also amplified due to stronger wind stress and vertical mixing, potentially influencing subsequent local atmospheric conditions. Overall, this work demonstrates that ocean bio-optical processes can meaningfully impact Mediterranean cyclone behavior, highlighting the importance of using appropriate underwater light attenuation schemes and ocean color remote sensing data in coupled models. Full article

Artificial Light at Night (ALAN) is a recent issue of concern for researchers primarily working on the anthropogenic impacts on animal and ecosystem health. Our concern is associated with the ALAN exposure to an aquatic ecosystem by disrupting the natural dark–light cycle, which is essential for maintaining the overall health of the ecosystem and its inhabitants. In this study, we have attempted to understand the adverse consequences of ALAN in inducing neuro-behavioural stress in a freshwater prawn species (aquatic arthropod) Macrobrachium lamarrei by considering grooming behaviour, a well-established indicator of neurological stress in animals. Our results show that continuous ALAN exposure (for seven days) can increase collective grooming activity in Macrobrachium lamarrei over time. In our experiment, we have used two intensities of ALAN (50 and 120 lux). Although the response (in terms collective grooming) to both intensities are apparently different, our fundamental hypothesis is confirmed, where it is evident that prolonged light exposure can induce an elevation in cumulative grooming performances in a freshwater prawn population. Full article

Hydraulic shear has been widely accepted as one of the essential factors modulating phytoplankton growth. Previous experimental studies of algal growth have been conducted at the macroscopic level, and direct observation at the cell scale has been lacking. In this study, an algal-cell dynamic continuous observation platform (ACDCOP) is proposed with a parallel-plate flow chamber (PPFC) to capture cellular growth images which are then used as input to a computer vision algorithm featuring a pre-trained backpropagation neural network to quantitatively evaluate the volumes and volumetric growth rates of individual cells. The platform was applied to investigate the growth of Scenedesmus quadricauda cells under different hydraulic shear stress conditions. The results indicated that the threshold shear stress for the development of Scenedesmus quadricauda cells was 270 µL min⁻¹ (5.62 × 10⁻⁵ m² s⁻³). Cellular growth was inhibited at very low and very high intensities of hydraulic shear. Among all the experimental groups, the longest growth period for a cell, from attachment to PPFC to cell division, was 5.7 days. Cells with larger initial volumes produced larger volumes at division. The proposed platform could provide a novel approach for algal research by enabling direct observation of algal growth at the cell scale, and could potentially be applied to investigate the impacts of various environmental stressors such as nutrient, temperature, and light on cellular growth in different algal species. Full article

Light intensity and spectral quality play crucial roles in microalgal growth and biochemical biosynthesis. This study investigates the effects of different light intensities (3000, 8000 and 15,000 lux) and colors (red, white, yellow and green) on the growth and metabolites of Nephroselmis sp. Moderate intensity (8000 lux) of white light is sufficient to produce this microalga. The colors of light strongly affect the parameters of the growth of Nephroselmis under each light intensity (p < 0.05). The yellow and green light supported the highest growth rates for the three intensities. Blue and green light at 15,000 Lux stimulates high levels of chl-a corresponding to antenna size 2.80 and 2.46. Nephroselmis illuminated with red light synthesizes carotenoids reaching 13 µg mL⁻¹ at 15,000 lux. This latter for each color stops the proliferation of Nephroselmis, and cells shift their metabolism towards the accumulation of protein. Nephroselmis accumulates more protein, followed by carbohydrates, lipids and polyphenols. Nephroselmis exhibited the highest protein (64% D.W) content when cultured under white light, and the green at 15,000 lux enhanced their production. Nephroselmis is rich in carbohydrates, which accounted for more than 20% D.W under all combinations of light intensities and colors. The accumulation of polyphenols and carotenoids under high-intensity red and white light may reflect an oxidative stress response, suggesting their role as protective antioxidants. The capacity of Nephroselmis sp. to thrive and synthesize valuable metabolites under variable light regimes underscores its potential as a robust candidate for the production of various molecules. Full article

Objectives: Light intensity is a critical environmental factor regulating plant growth, development, and stress adaptation. However, the physiological and molecular mechanisms underlying light responses in Aconitum kusnezoffii, a valuable alpine medicinal plant, remain poorly understood. This study aimed to elucidate the adaptive strategies of A. kusnezoffii under different light intensities through integrated physiological and transcriptomic analyses. Methods: Two-year-old A. kusnezoffii plants were exposed to three controlled light regimes (790, 620, and 450 lx). Leaf anatomical traits were assessed via histological sectioning and microscopic imaging. Antioxidant enzyme activities (CAT, POD, and SOD), membrane lipid peroxidation (MDA content), osmoregulatory substances, and carbon metabolites were quantified using standard biochemical assays. Transcriptomic profiling was conducted using Illumina RNA-seq, with differentially expressed genes (DEGs) identified through DESeq2 and functionally annotated via GO and KEGG enrichment analyses. Results: Moderate light (620 lx) promoted optimal leaf structure by enhancing palisade tissue development and epidermal thickening, while reducing membrane lipid peroxidation. Antioxidant defense capacity was elevated through higher CAT, POD, and SOD activities, alongside increased accumulation of soluble proteins, sugars, and starch. Transcriptomic analysis revealed DEGs enriched in photosynthesis, monoterpenoid biosynthesis, hormone signaling, and glutathione metabolism pathways. Key positive regulators (PHY and HY5) were upregulated, whereas negative regulators (COP1 and PIFs) were suppressed, collectively facilitating chloroplast development and photomorphogenesis. Trend analysis indicated a “down–up” gene expression pattern, with early suppression of stress-responsive genes followed by activation of photosynthetic and metabolic processes. Conclusions: A. kusnezoffii employs a coordinated, multi-level adaptation strategy under moderate light (620 lx), integrating leaf structural optimization, enhanced antioxidant defense, and dynamic transcriptomic reprogramming to maintain energy balance, redox homeostasis, and photomorphogenic flexibility. These findings provide a theoretical foundation for optimizing artificial cultivation and light management of alpine medicinal plants. Full article

Light quality and duration profoundly influence the growth and productivity of plant species. This study investigated the effects of a blue–red LED light combination, known to induce flowering, on the physiological state and content of biologically active substances in catmint (Nepeta nuda L.) grown under controlled in vitro conditions. White light (W) was used as a control and compared with two blue–red intensities: BR (high-intensity blue–red light) and BRS (low-intensity blue–red light or “BR with shadow”). BR-treated plants showed increased leaf area, mesophyll thickness, biomass and starch content but reduced levels of plastid pigments. BR also modified the oxidative state of plants by inducing lipid peroxidation while simultaneously activating ROS scavenging mechanisms and enhancing phenolic antioxidants. Interestingly, BR decreased the accumulation of the Nepeta sp.-specific iridoid, nepetalactone. These effects appear to be regulated by the phytohormones auxin, abscisic acid and jasmonates. BRS treatment produced effects similar to the W control but led to increased plant height and reduced leaf area and thickness. Both BR and BRS regimes induced the accumulation of proteins and amino acids. We conclude that blue–red light can enhance the survival capacity of micropropagated N. nuda during subsequent soil adaptation, suggesting that similar light pre-treatment could improve plant performance under stress conditions. Full article

Continuous blood pressure (BP) monitoring provides valuable insight into the body’s dynamic cardiovascular regulation across various physiological states such as physical activity, emotional stress, postural changes, and sleep. Continuous BP monitoring captures different variations in systolic and diastolic pressures, reflecting autonomic nervous system activity, vascular compliance, and circadian rhythms. This enables early identification of abnormal BP trends and allows for timely diagnosis and interventions to reduce the risk of cardiovascular diseases (CVDs) such as hypertension, stroke, heart failure, and chronic kidney disease as well as chronic stress or anxiety disorders. To facilitate continuous BP monitoring, we propose an AI-powered estimation framework. The proposed framework first uses an expert-driven feature engineering approach that systematically extracts physiological features from photoplethysmogram (PPG)-based arterial pulse waveforms (APWs). Extracted features include pulse rate, ascending/descending times, pulse width, slopes, intensity variations, and waveform areas. These features are fused with demographic data (age, gender, height, weight, BMI) to enhance model robustness and accuracy across diverse populations. The framework utilizes a Tab-Transformer to learn rich feature embeddings, which are then processed through an ensemble machine learning framework consisting of CatBoost, XGBoost, and LightGBM. Evaluated on a dataset of 1000 subjects, the model achieves Mean Absolute Errors (MAE) of 3.87 mmHg (SBP) and 2.50 mmHg (DBP), meeting British Hypertension Society (BHS) Grade A and Association for the Advancement of Medical Instrumentation (AAMI) standards. The proposed architecture advances non-invasive, AI-driven solutions for dynamic cardiovascular health monitoring. Full article

Hierarchical surface structuring is a critical aspect of advanced materials design, impacting fields ranging from optics to biomimetics. Among several laser-based methods for complex structuring of photo-responsive surfaces, the broadband vectorial interferometry proposed here offers unique performances. Such a method leverages a polychromatic laser source, an unconventional choice for holographic encoding, to achieve deterministic multiscale surface structuring through interference light patterning. Azopolymer films are used as photosensitive substrates. By exploring the interaction between optomechanical stress modulations at different spatial periodicities induced within the polymer bulk, we demonstrate the emergence of hierarchical Fourier surfaces composed of multiple deterministic levels. These structures range from sub-micrometer to tens of micrometers scale, exhibiting a high degree of control over their morphology. The experimental findings reveal that the optical encoding scheme significantly influences the resulting topographies. The polarization light patterns lead to more regular and symmetric hierarchical structures compared to those obtained with intensity patterns, underscoring the role of vectorial light properties in controlling surface morphologies. The proposed method is fully scalable, compatible with more complex recording schemes (including multi-beam interference), and it is applicable to a wide range of advanced technological fields. These include optics and photonics (diffractive elements, polarimetric devices), biomimetic surfaces, topographical design, information encoding, and anti-counterfeiting, offering a rapid, reliable, and versatile strategy for high-precision surface structuring at a submicrometric scale. Full article

Thylakoid rhodanese-like protein (TROL) serves as a thylakoid membrane hinge linking photosynthetic electron transport chain (PETC) complexes to nicotinamide adenine dinucleotide phosphate (NADPH) synthesis. TROL is the docking site for the flavoenzyme ferredoxin-NADP⁺ oxidoreductase (FNR). Our prior work indicates that the TROL-FNR complex maintains redox equilibrium in chloroplasts and systemically in plant cells. Improvement in the knowledge of redox regulation mechanisms is critical for engineering stress-tolerant plants in times of elevated global drought intensity. To further test this hypothesis and confirm our previous results, we monitored light-independent ROS propagation in the leaves of Arabidopsis wild type (WT), TROL knock-out (KO), and TROL ΔRHO (RHO-domain deletion mutant) mutant plants in situ by using confocal laser scanning microscopy with specific fluorescent probes for the three different ROS: O₂^·−, H₂O₂, and ¹O₂. Plants were grown under the conditions of normal substrate moisture and under drought stress conditions. Under the drought stress conditions, the TROL KO line showed ≈32% less O₂^·− while the TROL ΔRHO line showed ≈49% less H₂O₂ in comparison with the WT. This research confirms the role of dynamical TROL-FNR complex formation in redox equilibrium maintenance by redirecting electrons in alternative sinks under stress and also points it out as promising target for stress-tolerant plant engineering. Full article

Background/Objectives: Doxorubicin (DOX), a widely used anthracycline chemotherapeutic agent, is recognized for its efficacy in treating various malignancies. However, its clinical application is critically limited due to dose-dependent cardiotoxicity, predominantly induced by oxidative stress and compromised antioxidant defenses. Photobiomodulation (PBM), a non-invasive intervention that utilizes low-intensity light, has emerged as a promising therapeutic modality in regenerative medicine, demonstrating benefits such as enhanced tissue repair, reduced inflammation, and protection against oxidative damage. This investigation sought to evaluate the cardioprotective effects of PBM preconditioning in human-induced pluripotent stem cell-derived ventricular cardiomyocytes (hiPSC-vCMs) subjected to DOX-induced toxicity. Methods: Human iPSC-vCMs were allocated into three experimental groups: control cells (untreated), DOX-treated cells (exposed to 2 μM DOX for 24 h), and PBM+DOX-treated cells (preconditioned with PBM, utilizing 660 nm ±10 nm LED light at an intensity of 10 mW/cm² for 500 s, delivering an energy dose of 5 J/cm², followed by DOX exposure). Cell viability assessments were conducted in conjunction with evaluations of oxidative stress markers, including antioxidant enzyme activities and malondialdehyde (MDA) levels. Furthermore, transcriptional profiling of 40 genes implicated in cardiac dysfunction was performed using TaqMan quantitative polymerase chain reaction (qPCR), complemented by analyses of protein expression for markers of cardiac stress, inflammation, and apoptosis. Results: Exposure to DOX markedly reduced the viability of hiPSC-vCMs. The cells exhibited significant alterations in the expression of 32 out of 40 genes (80%) after DOX exposure, reflecting the upregulation of markers associated with apoptosis, inflammation, and adverse cardiac remodeling. PBM preconditioning partially restored the cell viability, modulating the expression of 20 genes (50%), effectively counteracting a substantial proportion of the dysregulation induced by DOX. Notably, PBM enhanced the expression of genes responsible for antioxidant defense, augmented antioxidant enzyme activity, and reduced oxidative stress indicators such as MDA levels. Additional benefits included downregulating stress-related mRNA markers (HSP1A1 and TNC) and apoptotic markers (BAX and TP53). PBM also demonstrated gene reprogramming effects in ventricular cells, encompassing regulatory changes in NPPA, NPPB, and MYH6. PBM reduced the protein expression levels of IL-6, TNF, and apoptotic markers in alignment with their corresponding mRNA expression profiles. Notably, PBM preconditioning showed a diminished expression of BNP, emphasizing its positive impact on mitigating cardiac stress. Conclusions: This study demonstrates that PBM preconditioning is an effective strategy for reducing DOX-induced chemotherapy-related cardiotoxicity by enhancing cell viability and modulating signaling pathways associated with oxidative stress, as well as inflammatory and hypertrophic markers. Full article

Background: Reliable and non-invasive methods for assessing welfare in poultry are essential for improving evidence-based welfare monitoring and advancing management practices in commercial production systems. The iris-to-pupil (IP) ratio, previously validated by our group in primates and cattle, reflects autonomic nervous system balance and may serve as a physiological indicator of stress in laying hens. This study evaluated the utility of the IP ratio under field conditions across diverse commercial layer housing systems. Materials and Methods: In total, 296 laying hens (Lohmann Brown, n = 269; White Leghorn, n = 27) were studied across four locations in Canada housed under different systems: Guelph (indoor; pen), Spring Island (outdoor and scratch; organic), Ottawa (outdoor, indoor and scratch; free-range), and Toronto (outdoor and hobby; free-range). High-resolution photographs of the eye were taken under ambient lighting. Light intensity was measured using the light meter app. The IP ratio was calculated using NIH ImageJ software (Version 1.54p). Statistical analysis included one-way ANOVA and linear regression using GraphPad Prism (Version 5). Results: Birds housed outdoors had the highest IP ratios, followed by those in scratch systems, while indoor and pen-housed birds had the lowest IP ratios (p < 0.001). Subgroup analyses of birds in Ottawa and Spring Island farms confirmed significantly higher IP ratios in outdoor environments compared to indoor and scratch systems (p < 0.001). The IP ratio correlated weakly with ambient light intensity (r² = 0.25) and age (r² = 0.05), indicating minimal influence of these variables. Although White Leghorn hens showed lower IP ratios than Lohmann Browns, this difference was confounded by housing type; all White Leghorns were housed in pens. Thus, housing system but not breed was the primary driver of IP variation. Conclusions: The IP ratio is a robust, non-invasive physiological marker of welfare assessment in laying hens, sensitive to housing environment but minimally influenced by light or age. Its potential for integration with digital imaging technologies supports its use in scalable welfare assessment protocols. Full article

It is projected that the world population will quadruple over the next century, and to meet future food demands, agricultural production will need to increase by 70%. Therefore, there has been a transition from traditional farming methods to autonomous modern agriculture. One such modern technique is aeroponic farming, in which plants are grown without soil under controlled and hygienic conditions. In aeroponic farming, plants are significantly less affected by climatic conditions, infectious diseases, and biotic and abiotic stresses, such as pest infestations. Additionally, this method can reduce water, nutrient, and pesticide usage by 98%, 60%, and 100%, respectively, while increasing the yield by 45–75% compared to traditional farming. In this study, a three-dimensional industrial design of an innovative aeroponic plant growth chamber was presented for use by individuals, researchers, and professional growers. The proposed chamber design is modular and open to further innovation. Unlike existing chambers, it includes load cells that enable real-time monitoring of the fresh weight of the plant. Furthermore, cameras were integrated into the chamber to track plant growth and changes over time and weight. Additionally, RGB power LEDs were placed on the inner ceiling of the chamber to provide an optimal lighting intensity and spectrum based on the cultivated plant species. A customizable chamber design was introduced, allowing users to determine the growing tray and nutrient nozzles according to the type and quantity of plants. Finally, system models were developed for temperature control of the chamber. Temperature control was implemented using a proportional-integral-derivative controller optimized with particle swarm optimization, radial movement optimization, differential evolution, and mayfly optimization algorithms for the gain parameters. The simulation results indicate that the temperatures of the growing and feeding chambers in the cabinet reached a steady state within 260 s, with an offset error of no more than 0.5 °C. This result demonstrates the accuracy of the derived model and the effectiveness of the optimized controllers. Full article

Skin aging is a multifactorial process driven by both intrinsic mechanisms—such as telomere shortening, oxidative stress, hormonal decline, and impaired autophagy—and extrinsic influences including ultraviolet radiation, pollution, smoking, and diet. Together, these factors lead to the structural and functional deterioration of the skin, manifesting as wrinkles, pigmentation disorders, thinning, and reduced elasticity. This review provides an integrative overview of the biological, molecular, and clinical dimensions of skin aging, emphasizing the interplay between inflammation, extracellular matrix degradation, and senescence-associated signaling pathways. We examine histopathological hallmarks and molecular markers and discuss the influence of genetic and ethnic variations on aging phenotypes. Current therapeutic strategies are explored, ranging from topical agents (e.g., retinoids, antioxidants, niacinamide) to procedural interventions such as lasers, intense pulsed light, photodynamic therapy, microneedling, and injectable biostimulators. Special attention is given to emerging approaches such as microneedle delivery systems, with mention of exosome-based therapies. The review underscores the importance of personalized anti-aging regimens based on biological age, phototype, and lifestyle factors. As the field advances, integrating mechanistic insights with individualized treatment selection will be key to optimizing skin rejuvenation and preserving long-term dermal health. Full article

Ultraviolet B (UVB), a component of solar ultraviolet light, is a major contributor to skin photodamage. UVB exposure primarily affects the epidermis, which leads to wrinkle formation, loss of skin elasticity, oxidative stress, and inflammation. Prolonged or intense UVB exposure can increase the risk of skin cancer. Collagen peptides are known as functional foods that improve skin dryness and wound healing. In this study, we aimed to investigate the protective and ameliorative effects of a low-molecular-weight collagen peptide (LMWCP) with a high absorption rate and photodamage. In vitro analysis using human dermal fibroblasts (HDFs) demonstrated that LMWCP promoted skin protection by increasing procollagen type I production, enhancing cell proliferation and migration, and inhibiting MMP-1 activity. Furthermore, LMWCP intake was indicated by improved skin hydration, reduced trans-epidermal water loss (TEWL), and changes in the clinical parameters, including skin elasticity, erythema, and scaling scores in UVB-exposed hairless mice. In the UVB-damaged tissues, an increase in skin elasticity-related enzymes was observed along with a decrease in aging-related and pro-inflammatory gene expression. Histological analysis revealed an increase in collagen content and restoration of dermal thickness. These findings suggested that LMWCP has significant benefits in preventing and improving UVB-induced skin damage. Full article

The aim of this work is to explore and understand the lived experience of nurses who chose to schedule visits with an Emotional Support Animal (ESA), i.e., a dog, during their working shift. Background/Objectives: Nursing practice is rigorous, weighted with intense responsibility that creates an environment conducive to stress and anxiety for the nurses, who have reported a higher level of work stress than other healthcare professionals. Knowing and addressing the factors impacting mental health/nurses’ well-being is crucial to providing care to patients. Stressful work environments result in burnout, compassion fatigue, depression, anxiety, suicide, and resignation. Understanding nurses’ perspectives on work related stress encourages hospitals to structure practices supporting nurses’ mental health and ability to provide quality care. Methods: A qualitative hermeneutic phenomenological approach was employed. Participants scheduled six weekly 10-min visits with Rex, a certified Service Dog for anxiety depression and PTSD, and registered ESA. A sample of 11 RNs participated in Rex visits at the workplace; field notes were taken during observations of visits. Semi-structured 30-min interviews conducted via Zoom, audio-recorded, and transcribed with NVivo were conducted. Results: Data were examined with Interpretative Phenomenological Analysis. Four main themes emerged: Preparing for the unknown, Doing the work, Refueling and resetting-Visits with Rex, What about nurses? Conclusions: This study highlights the need for nurses and hospital systems to incorporate self-care/self-reflection, including time/opportunities for nurses’ stress management during their practice. Knowledge of nurses receiving ESA interventions sheds light on how to protect/preserve the well-being of nurses practicing in this demanding profession. ESAs for nurses in the workplace offers an option to utilize dog therapy to re-energize and continue their shift renewed and refreshed. Full article