Search Results (361)

To address the issues of insulation layer damage and conductor exposure in offshore floating photovoltaic systems occurring in shallow marine regions characterized by significant tidal ranges under multi-field coupling effects, an overhead cable laying scheme based on the hybrid pile–floater structure is proposed, while its mechanical response is investigated in this paper. The motion response model of the floating platform, considering wind load, wave load, current load, and mooring load, as well as the equivalent density and mathematical model of the overhead cable are established. The mechanical response characteristics of the overhead cable are analyzed through finite element analysis software. The results indicate that the overhead cable’s mechanical response is influenced by the span length and coupled wind–ice loads. Specifically, the tension exhibits a nonlinear increasing trend, while the deflection shows differential variations driven by the antagonistic interaction between wind and ice loads. The influence of ice loads on the configuration of overhead cables is significantly weaker than that of wind loads. This study provides crucial theoretical support for enhancing the lifespan of the overhead cable. Full article

Coastal pond-to-mangrove restoration has become a prominent Nature-based Solution, yet its short-term ecological effects on waterbird communities remain unclear. We assessed taxonomic, functional, and compositional responses of waterbirds to large-scale restoration in Bamen Bay, Hainan Island, using BACI-style comparisons between restored and unrestored aquaculture ponds in 2021 and 2023. Restored areas exhibited higher taxonomic α diversity and functional richness (p < 0.001), coinciding with rapid habitat diversification following hydrological reconnection. Species richness (p < 0.001), Shannon diversity (p < 0.01), and functional richness (p < 0.01) were consistently higher in restored areas than in aquaculture ponds. In contrast, β diversity patterns diverged between habitats: restored areas remained relatively stable, whereas aquaculture ponds showed greater between-year compositional change (p < 0.05). Guild-specific responses revealed contrasting patterns: herons showed higher diversity in restored habitats (p < 0.05), whereas shorebirds exhibited no significant changes (p > 0.05), consistent with their dependence on open mudflats that were only partially retained. Although no significant declines were detected, functional richness tended to be lower in 2023 (p > 0.05), and ongoing mudflat loss suggests potential long-term risks for mudflat specialists, warranting extended monitoring. Taken together, our findings suggest that effective pond-to-mangrove restoration in Bamen Bay should balance mangrove expansion with the retention of tidal flats and managed shallow-water habitats to support diverse waterbird assemblages. Full article

Offshore floating photovoltaic (FPV) platforms are usually deployed in shallow waters with large tidal variations, where the modules of FPV are connected with each other via the connectors to form an array and mounted to the seabed via the mooring system. Therefore, the mooring system and module connectors have significant influence on the dynamic response characteristics of FPV. In targeting such shallow waters with large tidal ranges, this paper proposes four integrated mooring-connection schemes based on configuration and parameter customization guided by adaptability optimization, including two kinds of mooring systems, named as horizontal mooring system and catenary mooring system with clumps, and two kinds of connection schemes, named as cross-cable connection and hybrid connection, are proposed. The feasibility of the mooring systems to adhere to the tidal range and the influence of the connection schemes on the dynamic response of the FPV are numerically investigated in detail. Results indicate the two mooring systems have comparable positioning performance; horizontal mooring offers slightly better tidal adaptability but much higher mooring tension, compromising system safety. Hybrid connection yields smaller surge amplitudes than cross-cable connection but generates excessively large connection forces, also posing safety risks. Comprehensive comparison indicates that catenary mooring with clumps combined with cross-cable connection imposes lower requirements on platform structural safety factors, while horizontal mooring with cross-cable connection exhibits stronger adaptability to water level and environmental load direction changes in shallow waters. Full article

This study presents a systematic airfoil optimization framework to enhance the hydrodynamic performance of vertical-axis tidal turbines (VATTs) under low-flow conditions. The integrated methodology combines parameterized design, response surface methodology (RSM) optimization, and high-fidelity computational fluid dynamics (CFD) validation to investigate the effects of maximum thickness (Factor A), maximum thickness position (Factor B), and maximum camber (Factor C). The shear stress transport (SST) k-ω turbulence model was employed for flow simulation, with experimental validation conducted across Reynolds numbers from 5.2 × 10⁵ to 8.6 × 10⁵. The tip speed ratio (TSR) predictions demonstrated excellent agreement with experimental measurements, showing a maximum relative error of only 4.5%. From hundreds of Pareto-optimal solutions, five candidate designs were selected for high-fidelity verification. The final optimized airfoil (Optimized Foil 5) achieved a power coefficient (C_P) of 0.1887, representing a 27.5% improvement over the baseline National Advisory Committee for Aeronautics (NACA) 2414 airfoil. This optimal configuration features 23.51% maximum thickness, 30.14% maximum thickness position, and 3.99% maximum camber, with only 0.2% deviation between RSM prediction and CFD validation. The research establishes a reliable design framework for VATTs operating in low-velocity tidal streams, providing significant potential for harnessing previously uneconomical marine energy resources. Full article

Oil pollution effects on mangroves may be categorised as lethal (acute) and sublethal (chronic). Lethal effects usually occur at high oil dosage, which smothers and kills the entire root system and causes mass mortality. Sublethal effects occur when oil enters with tidal inundation or becomes trapped in sediments, resulting in prolonged deleterious effects that do not cause mortality. Long-term sublethal effects, however, are poorly understood. This review summarises the current information on the sublethal effects of oil pollution on mangroves. It begins by examining the characteristics of oil and then evaluates the effects of oil on propagules, roots, and leaves, as well as the underlying ecophysiological mechanisms of toxicity. Within cells, PAHs target organelles responsible for cell metabolism and energy relations, including the nucleus, mitochondria, and chloroplasts. Oil disorganises and disintegrates the lipid components of membranes, increasing their permeability. Responses of mangroves to oil include leaf senescence, defoliation and reductions in photosynthesis and biomass. Oil also decreases reproductive capacity, inhibits germination, induces mutations, and causes the development of anomalous growth forms, as well as oxidative stress and mortality. Abnormal root development at the lower portions of the stem and chlorophyll-deficient propagules are suggested as biological indicators of oil contamination in mangroves. Full article

Background: Sleep quality is critical to health, and its disturbances may affect multiple systems, including autonomic and respiratory regulation. However, its relationship with chronotropic and ventilatory responses in healthy young men remains underexplored. Thus, the study aimed to investigate the relationship between sleep quality, as measured by the Pittsburgh Sleep Quality Index (PSQI), and chronotropic and ventilatory responses during cardiopulmonary exercise testing (CPET) in a healthy young male population and to explore group differences between good and poor sleepers. Methods: Thirty-three healthy men completed the PSQI and a graded CPET with breath-by-breath gas analysis. Pearson correlation was used to examine relationships between the PSQI and CPET outcomes: chronotropic response (%), tidal volume (VT), minute ventilation (VE), VO₂, VCO₂, expired O₂/CO₂, VE/VO₂, and VE/VCO₂. After accounting for age, height, and weight, the correlation was reassessed. Secondary analyses using a standard cut-off point compared good (PSQI < 5) vs. poor sleepers (PSQI ≥ 5) with Welch’s t-tests. Results: Participants were predominantly poor sleepers (84.8%; PSQI 7.3 ± 3.2). A higher PSQI correlated with lower chronotropic response (r = −0.35, p = 0.04), lower VT (r = −0.42, p = 0.02), lower expired O₂ (r = −0.46, p = 0.01), and lower expired CO₂ (r = −0.33, p = 0.05). Associations with VE, VO₂, VCO₂, VE/VO₂, and VE/VCO₂ were small and non-significant (p > 0.05). When age, height, and weight were controlled for, the attenuated chronotropic response association with the PSQI was not significant; however, the PSQI association remained significant for expired O₂ (r = −0.32, p = 0.04), with a trend for VT. In group comparisons, chronotropic response was higher but not significant; good sleepers showed higher VT and greater expired O₂/CO₂ (p < 0.05). Conclusions: Poorer sleep quality was initially associated with multiple cardiopulmonary responses at peak during CPET. However, after controlling for age and anthropometry measures, only expired O₂ remained linked. The findings suggest that routine sleep quality screening may add interpretive value to CPET by flagging individuals with reduced ventilatory depth, warranting prospective studies to test whether improving sleep quality can enhance exercise responses. Full article

Music is considered a non-pharmacological adjunct in human anaesthesia, contributing to anaesthetic- and analgesic-sparing effects, modulating autonomic responses, and enhancing recovery. However, its effects in veterinary surgical settings remain largely unexplored. This study aimed to explore the potential influence of intraoperative music on anaesthetic and analgesic requirements, autonomic parameters, intraoperative adverse effects, and recovery quality in dogs undergoing elective ovariohysterectomy under general anaesthesia. In this prospective, randomized exploratory study, client-owned female dogs (n = 28) were randomly assigned to either a music group (exposed to instrumental classical music intraoperatively) or a control group (no music). All dogs received a standardized anaesthetic protocol. Mean end-tidal isoflurane concentrations, intraoperative analgesic requirements, heart rate, respiratory rate, blood pressure, adverse effects, and recovery quality were recorded and compared between groups using unpaired t-test, Mann–Whitney U test, or Fisher’s exact test, as appropriate (p < 0.05). No statistically significant differences were observed. Therefore, intraoperative music did not produce measurable effects on the assessed parameters. While no apparent benefit was observed in this study, future studies with larger sample sizes should investigate music-based interventions in more challenging or variable clinical scenarios. Additionally, further research is needed to clarify the extent to which anaesthetics suppress auditory processing. This exploratory investigation contributes to the limited body of evidence on auditory stimulation in veterinary anaesthesia. Full article

To quantitatively assess the storm surge induced by Super Typhoon Doksuri (2023) along the complex coastline of Fujian Province, a high-resolution Finite-Volume Coastal Ocean Model (FVCOM) was developed, driven by a refined Holland–ERA5 hybrid wind field with integrated physical corrections. The hybrid approach retains the spatiotemporal coherence of the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 reanalysis in the far field, while incorporating explicit inner-core adjustments for quadrant asymmetry, sea-surface-temperature dependency, and bounded decay after landfall. A series of numerical experiments were conducted, including paired tidal-only and full storm-forcing simulations, along with a systematic sensitivity ensemble in which bottom-friction parameters were perturbed and the anomalous (typhoon-related) wind component was scaled by factors ranging from 0.8 to 1.2. Static sea-level rise (SLR) scenarios (+0.3 m, +0.5 m, +1.0 m) were imposed to evaluate their influence on extreme water levels. Storm surge extremes were analyzed using a multi-scale coastal buffer framework, comparing two extreme extraction methods: element-mean followed by time-maximum, and node-maximum then assigned to elements. The model demonstrates high skill in reproducing astronomical tides (Pearson r = 0.979–0.993) and hourly water level series (Pearson r > 0.98) at key validation stations. Results indicate strong spatial heterogeneity in the sensitivity of surge levels to both bottom friction and wind intensity. While total peak water levels rise nearly linearly with SLR, the storm surge component itself exhibits a nonlinear response. The choice of extreme-extraction method significantly influences design values, with the node-based approach yielding peak values 0.8% to 4.5% higher than the cell-averaged method. These findings highlight the importance of using physically motivated adjustments to wind fields, extreme-value analysis across multiple coastal buffer scales, and uncertainty quantification in future SLR-informed coastal risk assessments. By integrating analytical, physics-based inner-core corrections with sensitivity experiments and multi-scale analysis, this study provides an enhanced framework for storm surge modeling suited to engineering and coastal management applications. Full article

A remote operator (RO) of Maritime Autonomous Surface Ships (MASSs) is required to respond to the effects of external forces, such as tidal currents, and ensure safe, efficient, and sustainable navigation. However, previous studies primarily focus on the physical movement changes of the ship caused by tidal currents, with limited research addressing the impact of external forces on ship maneuverability and steering response. Therefore, analysis of an RO’s steering competence and identification features for training is important. In the context of sustainable maritime operations and navigation, the purpose of this study is to analyze the competence of ROs in steering ships under the effects of tidal currents and to identify priority training features as a foundational framework for future applications to MASS remote operation training. Twenty third-year cadets at Mokpo National Maritime University participated in simulator experiments designed to analyze steering competence in the presence and absence of tidal currents in a controlled environment. The experimental results showed the difference in steering performance considering the effect of tidal currents, and machine learning algorithms were used to identify priority training features. Machine learning analysis ranked Altering to ROT zero time (ART) and Maximum port ROT (MRT) as the two most influential steering features among the four identified variables, consistently showing the highest importance scores across all models. This simulator-based study identifies tidal current response steering features as a foundational framework for RO training and competence evaluation, which may inform the design of future MASS remote operation training programs after further validation. Full article

This study investigates the morphodynamic evolution of an embayed cobble beach located on a mesotidal cliff coast in northern Spain. La Maruca/Pinquel beach was selected for its distinctive geomorphological setting, perched on a well-sorted cobble substrate and bordered by a slightly elevated (less than 1 m) wave-cut platform. Firstly, the availability of orthophotos and the achievement of field surveys enabled a detailed topographic mapping of morphological features. Sedimentological analyses based on grain size and clast shape revealed characteristics indicative of prolonged low-energy wave conditions. A permanent sharply crested ridge and ephemeral staggered tidal berms define the morphology of the beach. Additional depositional features such as washovers, tabular structures, and lobes are also well developed. Sediment accumulation is most pronounced in the western sector, where overwash lobes migrate landward. A W-to-E gradient in cobble size and the presence of boulders in the lower foreshore can be observed. Secondly, a morphosedimentary model was developed based on the obtained data to interpret the beach’s dynamic behavior under current and projected coastal forcing. Finally, by analyzing orthophotographs spanning a 40-year period (1984–2024), the long-term geomorphological evolution of the beach was documented. The results reveal significant morphological transformations, notably a shoreline retreat of approximately 12 m and a reduction in the cobble-covered surface area, among other findings. Future analyses of sediment transport processes and lithological responses to erosion will be able to offer a deeper understanding of the complex behavior and resilience of pebble beach systems in response to changing environmental conditions. Full article

Local scour around support structures has remained a critical barrier to tidal stream turbine deployment in energetic marine channels since loss of embedment and bearing capacity has undermined stability and delayed commercialization. This review identifies key mechanisms, practical implications, and forward-looking strategies related to local scour. It highlights that rotor operation, small tip clearance, and helical wakes can significantly intensify near-bed shear stress and erosion relative to monopile foundations without turbine rotation. Scour behavior is compared across monopile, tripod, jacket, and gravity-based foundations under steady flow, reversing tides, and combined wave and current conditions, revealing their influence on depth and morphology. The review further assesses coupled interactions among waves, oscillatory currents, turbine-induced flow, and seabed response, including sediment transport, transient pore pressure, and liquefaction risk. Advances in prediction methods spanning laboratory experiments, high-fidelity simulations, semi-empirical models, and data-driven techniques are synthesized, and mitigation strategies are evaluated across passive, active, and eco-integrated approaches. Remaining challenges and specific research needs are outlined, including array-scale effects, monitoring standards, and integration of design frameworks. The review concludes with future directions to support safe, efficient, and sustainable turbine deployment. Full article

Maritime disasters pose substantial social and economic challenges and often require complex, resource-intensive search and rescue operations to minimize loss of life and damage to infrastructure. This study proposes a sustainable and quantitative framework for planning and managing underwater search and rescue operations in strong tidal current environments, with reference to the Sewol ferry disaster. Hydrodynamic current predictions over a 31-day period were analyzed to determine tidal-induced diving cycles and to estimate the depth-specific diveable time (DAT) under safe operating limits of 1 knot for a self-contained underwater breathing apparatus (SCUBA) and 1.5 knots for surface-supplied diving systems (SSDSs). Two representative dive profiles were developed: a no-decompression SCUBA plan for 26 m hull diving and a staged-decompression SSDS plan for 48 m seabed diving, considering oxygen toxicity and nitrogen narcosis limits. Workable time (WAT) analysis indicated SCUBA as optimal for hull tasks (WAT/DAT = 0.83), whereas the SSDS provided extended efficiency for deep-water operations. A redeployment model based on surface interval constraints reduced diver staffing requirements by approximately 28%. The proposed framework enhances the sustainability and resilience of marine disaster response by optimizing diver safety, operational efficiency, and resource management, contributing to sustainable marine safety systems and long-term emergency preparedness. Full article

Saltwater intrusion increasingly jeopardizes groundwater in low-lying coastal plains worldwide, where the combined effects of sea-level rise, land subsidence, and hydraulic regulation further exacerbate aquifer vulnerability and threaten the long-term sustainability of freshwater supplies. To move beyond sparse and fragmented piezometric observations, we propose “integrated coastal supersites”: wells equipped with multiparametric sensors and multilevel piezometers that couple high-resolution vertical conductivity–temperature–depth (CTD) profiling with continuous hydro-meteorological time series to monitor the hydrodynamic behavior of coastal aquifers and saltwater intrusion. This study describes the installation of two supersites and presents early insights from the first monitoring period, which, despite a short observation window limited to the summer season (July–September 2025), demonstrate the effectiveness of this approach. Two contrasting supersites were deployed in the coastal plain between the Brenta and Adige Rivers (Italy): Gorzone, characterized by a thick, laterally persistent aquitard, and Buoro, where the aquitard is thinner and discontinuous. Profiles and fixed sensors at both sites reveal a consistent fresh-to-saline transition in the phreatic aquifers and a secondary freshwater lens capping the confined systems. At Gorzone, the confining layer hydraulically isolates the deeper aquifer, preserving low salinity beneath a saline, tidally constrained phreatic zone. Groundwater heads oscillate by about 0.2 m, and rainfall events do not dilute salinity; instead, pressure transients—amplified by drainage regulation and inland-propagating tides—induce short-lived EC increases via upconing. Buoro shows smaller water-level variations, not always linked to rainfall, and, in contrast, exhibits partial vertical connectivity and faster dynamics: phreatic heads respond chiefly to internal drainage and local recharge, with rises rapidly damped by pumping, while salinity remains steady without episodic peaks. The confined aquifer shows buffered, delayed responses to surface forcings. Although the monitoring window is currently limited to 2025 through the summer season, these results offer compelling evidence that coastal supersites are reliable, scalable, and management-critical relevance platforms for groundwater calibration, forecasting, and long-term assessment. Full article

Rescue operations involving baleen whales trapped in dammed environments are difficult to perform successfully, yet increasingly relevant under growing coastal development. We report on a two-day (9–10 February 2023) rescue of a juvenile humpback whale trapped upstream of the Rance Tidal Power Station (TPS) in Brittany, France, providing rare peer-review evidence on response strategies in highly engineered estuaries. A collaborative, non-invasive strategy was implemented by adjusting water levels and creating artificial tidal currents to prevent the whale from stranding and to guide the individual back to open water. Approximately 100 people were mobilized as part of the rescue operation. This paper describes a detailed spatiotemporal account of the whale’s movements and a chronological record of the actions taken by the rescue team. After several attempts to guide it out, rescue efforts enabled its successful exit from the estuary on the second day of operations, and it was not subsequently reported stranded along the French coast. This case demonstrates the value of rapid multidisciplinary coordination between the French National Stranding Network (composed of marine scientists, veterinarians and local correspondents), local organizations, the local marine biology station, international marine mammal experts, national institutions, authorities and a tidal energy operator. Beyond documenting an unusual event, this paper provides operational lessons, highlighting (i) the adaptative management of a TPS as a guidance tool, (ii) the prioritization of animal welfare and responders’ safety, (iii) the effective public and media management and (iv) the involvement of trained volunteers during the rescue, promoting environmentally responsible behavior. These insights are transferable to other cases to inform future baleen whales rescue protocols in anthropogenic environments. Full article

Introduction/Goal: Stress and negative emotions have been shown to exert a substantial impact on cancer patients, affecting their ability to adapt to therapy and the overall effectiveness. Elevated cortisol levels, a stress-induced hormone, have been shown to suppress immune system function, potentially reducing the body’s capacity to combat cancer cells. On the contrary, prolactin, a hormone that stimulates the immune system, has shown potential in this context but requires further study. The objective of this study was to investigate the acute physiological changes that occur during a single Conscious Connected Breathing (CCB) session, as part of a larger investigation on Integrative Breathwork Psychotherapy (IBP), a novel integrative psychosomatic intervention designed to improve psychosomatic and immune status in cancer patients. Methods: The project involved 93 breast cancer patients hospitalized for postoperative radiotherapy who participated in a ten-session IBP program. Fifty-six patients agreed to participate (response rate: 60%). During the experiment, 8 patients were excluded from the analysis. IBP consisted of small group sessions (up to six participants) conducted three times weekly. Each session included 45 min of CCB—defined as rhythmic circular nasal breathing at a depth exceeding resting tidal volume, without breath-holding, performed in a state of mindful acceptance—followed by 15 min of free emotional expression (verbal articulation of emerging feelings and sensations). This was a within-subject pre-post design: physiological measurements were obtained immediately before and 30 min into the tenth session (when participants had achieved technical proficiency) in all participants, who served as their own controls. Outcome measures included: arterialized capillary blood gas parameters (pH, pCO₂, pO₂, ctO₂, COHb, HHb, cH⁺), serum cortisol and prolactin concentrations, and immunoglobulin A (IgA). Results: During the CCB session, blood gas analysis revealed significant changes consistent with mild respiratory alkalosis: decreases in pCO₂ (p = 0.003), pO₂ (p < 0.001), cH⁺ (p < 0.001), ctO₂ (p < 0.001), COHb (p = 0.03), and HHb (p = 0.004), alongside an increase in pH (p < 0.001). Concurrently, prolactin levels increased significantly (p < 0.001), while cortisol (p < 0.001) and IgA (p < 0.001) decreased. Conclusions: This study is the first to analyze acute changes in capillary blood gas parameters and neuroendocrine balance during Conscious Connected Breathing sessions in cancer patients, revealing measurable immunostimulatory and stress-modulatory effects. The observed shift toward respiratory alkalosis, combined with increased prolactin and decreased cortisol, suggests that CCB may facilitate favorable neuroendocrine-immune interactions. These findings support the potential of breathwork as a complementary therapy for cancer patients. Further research is needed to explore underlying mechanisms and assess long-term psychological and immunological impacts. Full article