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Oceans are repositories of radionuclides. Radionuclides are transferred through the food chain and cause ionizing radiation hazards for marine organisms. In this study, the transfer characteristics of 226Ra, 40K, 14C, 3H, 137Cs and 90Sr in organisms at different trophic levels in the eastern coast of Yantai city were investigated. The risk of ionizing radiation to organisms was assessed using the ERICA Tool 2.0. The results show no significant changes in the concentration of any of the nuclides in the coastal area compared to the preoperation period of the nuclear power plant. The transfer factor of 137Cs, 40K, 226Ra, 14C, 90Sr and 3H at the different trophic levels of marine organisms were 2.09, 1.29, 1.17, 1.15, 1.06 and 0.74, respectively. The dose rates of ionizing radiation to organisms from six radionuclides ranged from 32.02 nGy·h-1 to 195.49 nGy·h-1 and had a mean value of 102.86 ± 57.30 nGy·h-1. The main artificial radionuclides (14C, 3H, 90Sr, 137Cs) released by nuclear power plants in the study area produced negligible radiation doses to marine organisms. However, other artificial radionuclides present in the effluents of nuclear power plants (99Tc, 110mAg and 131I) as well as other natural radionuclides (includes 210Po, 210Pb, etc) were not included, and further evaluation of these is recommended. [ABSTRACT FROM AUTHOR]

Chlorination of seawater forms a range of secondary oxidative species, collectively termed "chlorine-produced oxidants" (CPOs). These compounds do not have the same biocidal efficacy, the same fate and behavior in the marine environment, the same potential formation of chlorination by-products (CBPs), nor the same effects on marine organisms. Their chemical speciation is an important step toward an accurate assessment of the effectiveness of chlorination and the potential impacts of its releases, among others. The aim of this paper - which is the second of a trilogy dedicated to the chemical speciation of CPOs in seawater - is to cover all aspects related to CPOs analysis in seawater, from sampling to instrumental determination. First, it discusses the procedures involved in synthesis, storage, and standardization of analytical standards. Second, it deals with sampling and sample preparation, addressing all relevant issues related to these two key steps. Third, it provides a comprehensive and up-to-date overview of the colorimetric, titrimetric, and electrochemical methods used for CPOs determination and thoroughly discusses their advantages and limitations. Finally, this review ends with some recommendations for progress in the field of CPO analysis with the three aforementioned approaches. Chromatographic and mass spectrometric-based methods will be covered in the third and final article (Part III). [ABSTRACT FROM AUTHOR]

A large part of ocean surface is covered by calcareous deposits. The Low stiffness and weak particles of calcareous soils deposited by marine organisms showed significant particle breakage under applied loads, which resulted in different behavior compared to terrigenous soils. A series of compression drained triaxial tests were carried out to evaluate the monotonic shear behavior of crushable and non-crushable soils. Three different soils, including Firoozkuh siliceous sand (as a non-crushable soil) and Hormuz and Bushehr calcareous sands (as crushable soils) which were different in mineralogy compositions were obtained from northern and southern Iran. The specimens were prepared in different relative densities (i.e., loose, medium and dense conditions) and consolidated under confining pressures ranging from 100 to 600 kPa. The monotonic shear and dilatancy behaviors of the soils have been presented in detail and the effect of particle breakage has been discussed. The results showed that particle breakage has a significant effect on the mobilized friction and dilatancy angles of marine crushable soils. There is a linear relationship between the amount of particle breakage occurring during a triaxial test and breakage angle. In addition, the mineralogical difference influences the breakage properties of calcareous deposits. [ABSTRACT FROM AUTHOR]

• Energy extraction efficiency exhibits dual-peak shape with varying spring stiffness. • The first peak is heavily influenced by leading-edge vortices for lift generation. • It happens when system's natural frequency approximately matches pitching frequency. • Lamb vector, fluid acceleration, and pressure terms dominate lift generation. • The second peak is mainly caused by trailing-edge vortices for torque variations. Flapping airfoil energy harvesting has emerged as a promising paradigm inspired by birds and marine organisms. In this investigation, a semi-passive flapping airfoil device with a predetermined pitching motion was examined using a transient numerical simulation method employing an overlapping grid technique. The impact of the spring stiffness on the energy harvesting characteristics of the flapping airfoil was analyzed through the implementation of the integral momentum theorem and dynamic mode decomposition. The results demonstrated that the efficiency and power curves of the flapping airfoil exhibited a distinctive bimodal M shape in response to variations of the spring stiffness. The initial peak efficiency point, which corresponded to the system's natural frequency in proximity to the pitching frequency, was found to be heavily influenced by the presence of leading-edge vortexes, thereby influencing lift generation. By utilizing the integral momentum theorem, it was determined that the Lamb vector term, fluid acceleration term, and total pressure term predominantly contributed to the lift generation. The emergence of the second peak efficiency point was primarily linked to torque variations induced by trailing-edge vortexes. [ABSTRACT FROM AUTHOR]

Ocean acidification can negatively affect a broad range of physiological processes in marine shelled molluscs. Marine bioeroding organisms could, in contrast, benefit from ocean acidification due to reduced energetic costs of bioerosion. Ocean acidification could thus exacerbate negative effects (e.g. reduced growth) of ocean acidification and shell borers on oysters. The aim of this study was to assess the impact of ocean acidification on the oyster Ostrea chilensis, the boring sponge Cliona sp., and their host-parasite relationship. We exposed three sets of organisms 1) O. chilensis, 2) Cliona sp., and 3) O. chilensis infested with Cliona sp. to pHT 8.03, 7.83, and 7.63. Reduced pH had no significant effect on calcification, respiration and clearance rate of uninfested O. chilensis. Low pH significantly reduced calcification leading to net dissolution of oyster shells at pHT 7.63 in sponge infested oysters. Net dissolution was likely caused by increased bioerosion by Cliona sp. at pHT 7.63. Additionally, declining pH and sponge infestation had a significant negative antagonistic effect (less negative than predicted additively) on clearance rate. This interaction suggests that sponge infested oysters increase clearance rates to cope with higher energy demand of increased shell repair resulting from higher boring activity of Cliona sp. at low seawater pH. O. chilensis body condition was unaffected by sponge infestation, pH, and the interaction of the two. The reduction in calcification rate suggests sponge infestation and ocean acidification together would exacerbate direct (reduced growth) and indirect (e.g., increased predation) negative effects on oyster health and survival. Our results indicate that ocean acidification by the end of the century could have severe consequences for marine molluscs with boring organisms. [ABSTRACT FROM AUTHOR]

Saponins, consisting of sapogenins as their aglycones and carbohydrate chains, are widely found in plants and some marine organisms. Due to the complexity of the structure of saponins, involving different types of sapogenins and sugar moieties, investigation of their absorption and metabolism is limited, which further hinders the explanation of their bioactivities. Large molecular weight and complex structures limit the direct absorption of saponins rendering their low bioavailability. As such, their major modes of action may be due to interaction with the gastrointestinal environment, such as enzymes and nutrients, and interaction with the gut microbiota. Many studies have reported the interaction between saponins and gut microbiota, that is, the effects of saponins on changing the composition of gut microbiota, and gut microbiota playing an indispensable role in the biotransformation of saponins into sapogenins. However, the metabolic routes of saponins by gut microbiota and their mutual interactions are still sparse. Thus, this review summarizes the chemistry, absorption, and metabolic pathways of saponins, as well as their interactions with gut microbiota and impacts on gut health, to better understand how saponins exert their health-promoting functions. [ABSTRACT FROM AUTHOR]

AbstractFucose is abundant in marine organisms, primarily as fucoidan and fucosylated chondroitin sulfate. Our previous study characterized a sulfated and fucosylated glucuronomannan (SFGM) isolated from marine brown algae, exhibiting notable antiviral activity and potential for drug development. Herein, a trisaccharide fragment of this SFGM in the form of [α-L-Fuc(2, 4-diS)]-(1→3)-α-D-Man-(1→4)-α-D-GlcA-OMP was synthesized for the first time. Stereoselective formation of the α-1,2-cis-fucosidic bond was achieved by leveraging solvent effects. The sulfated trisaccharide as the final product, featuring a 2,4-diS-fucose unit and the p-methoxyphenyl group as a pendant at the anomeric position, was successfully accomplished. The synthetic strategy developed in this study offers a foundation for the pharmaceutical development of these SFGM oligosaccharides. [ABSTRACT FROM AUTHOR]

The rockfish (Sebastes schlegeli) and striped beakperch (Oplegnathus fasciatus) were released in marine ranching areas in Korea, Japan, and China to maintain fishery resources in coastal areas. To estimate the density and biomass of fishery resources, the target strength (TS) of target marine organisms is needed to scale integrated volume backscattering coefficients. In this study, the target strength–length (TS–L) relationship for live rockfish and striped beakperch was derived using ex situ methods at a frequency of 200 kHz. The TS-L function for rockfish and striped beakperch can be expressed as TSAvg. = 20logTL − 69.25 (R2 = 0.35) and TSAvg. = 20logFL − 67.01 (R2 = 0.31), respectively. These results can be used to assess the growth, density, and abundance of the two species using acoustics. [ABSTRACT FROM AUTHOR]

Ultrasonic technology has drawn extensive interests for its great potential in marine antifouling applications. However, its effects on the adhesion behavior of marine fouling organisms on marine structures remain underexplored. This work investigated how ultrasonic treatment impacted the adhesion of Pseudoalteromonas on a gel-like marine epoxy primer. And the process parameters for ultrasonic treatment were optimized using response surface analysis with Design-Expert software 11. The results revealed that ultrasonic treatment disrupted the cellular structure of Pseudoalteromonas, causing the deformation and fragmentation of the cell membrane, leading to bacterial death. Additionally, ultrasonic treatment reduced the particle size and Zeta potential value of Pseudoalteromonas, which disrupted the stability of bacterial suspensions. It also increased the relative surface hydrophobicity of Pseudoalteromonas cells, resulting in a reduction in adhesion to the gel-like marine epoxy primer. This study demonstrated that ultrasonic treatment significantly disturbed the adhesion behavior of microorganisms like Pseudoalteromonas on the gel-like marine epoxy primer, which provided an effective approach for controlling marine biofouling. [ABSTRACT FROM AUTHOR]

La ciguatéra est une intoxication alimentaire par organismes marins dont la clinique est polymorphe et doit faire éliminer des diagnostics différentiels. Un patient était hospitalisé pour un syndrome fébrile quelques jours après l'apparition de signes cliniques évocateurs d'une ciguatéra après avoir consommé un poisson du lagon. Il présentait également des signes neurologiques centraux et l'IRM cérébrale mettait en évidence une lésion du corps calleux. Une infection cutanée liée aux lésions de grattage était la cause de cet état fébrile et un diagnostic de CLOCCS était porté devant les lésions à l'IRM. Une atteinte neurologique centrale dans la ciguatéra est possible mais rare, un CLOCCS pouvant faire partie de ces atteintes. Un syndrome fébrile doit en revanche faire envisager un diagnostic alternatif ou une complication. Ciguatera is a food poisoning caused by marine organisms and has a polymoprhic clinic. Differential diagnoses need to be eliminated. A patient was hospitalized for a febrile syndrome a few days after the appearance of clinical signs suggestive of ciguatera after consuming lagoon fish. He also presented with central neurological signs and brain MRI revealed a lesion of the corpus callosum. A skin infection linked to the scratching lesions was the cause of this febrile state and a diagnosis of CLOCCS was made based on the lesions on MRI. A central neurological involvement in ciguatera is possible but rare, CLOCCS may be one of them. On the other hand, a febrile syndrome should lead to consider an differential diagnosis or a complication. [ABSTRACT FROM AUTHOR]

This study presents the development, validation and use of an approach for precise and accurate cadmium (Cd) isotopic analysis at low concentration levels using multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS). The MC-ICP-MS unit used was equipped with a standard sample introduction system, thus using an ICP operated under wet plasma conditions, and Faraday cup amplifiers equipped with a 1013 Ω resistor. One-column anion exchange chromatography allowed isolation of Cd with 80-99% recovery and absence of an effect of potential on-column fractionation on the isotope ratio results was demonstrated. Use of both an internal (using Ag) and an external (measured in a sample-standard bracketing sequence) standard was relied on for correction of the bias introduced by instrumental mass discrimination. A long-term precision of 0.09& (2SD) for δ114/110Cd was achieved at a Cd concentration of 10 ng mL-1. The method developed was validated by analysing NIST SRM 2711a (Montana soil) and NRC TORT-3 (Lobster hepatopancreas) reference materials, yielding results consistent with literature values. Subsequently, the method was applied to two Antarctic marine organisms Adamussium colbecki and Trematomus bernacchii, collected during both the 1990s and 2020s, to investigate its potential for identifying changes in the biogeochemical cycle of Cd over time and reveal natural or anthropogenic sources. A preferential uptake of the lighter Cd isotopes in both species was observed, indicated by negative δ114/110Cd values ranging between -0.24 and -0.09&. This finding is consistent with previous studies that have reported Cd fractionation during its uptake by marine organisms, with a preference for the lighter isotopes. No significant differences in δ114/110Cd values were observed between organs of the same species or between the same species collected in the different decades, suggesting minimal Cd isotope fractionation during internal transfer and consistent Cd sources over time. Comparison with literature data suggests that the Cd source in Antarctic biota may be predominantly of natural origin, with δ114/110Cd values indicating isotopically heavier Cd than that found in Cd-polluted areas. However, further Cd isotope ratio data from various Antarctic sample types are necessary to further evaluate the Cd sources in marine samples. [ABSTRACT FROM AUTHOR]

Kelps are resilient organisms, capable of thriving in high-energy wave environments. However, when hydrodynamic drag forces exerted by the wave environment exceed the kelps' structural limits, individuals become dislodged. Floating kelps generally follow ocean currents, traveling long distances until air-filled structures fail or the epibiont load becomes too great, causing them to sink to the seafloor. The ability of kelp to disperse over vast offshore and nearshore systems makes them important for organic subsidy and as a dispersal vector for marine organisms. Previous research on dislodged macroalgae focused on context-specific rafts, limiting insights into the broader ecological role of floating kelp. This study employed a site-specific Lagrangian trajectory model to describe the spatial distribution of floating Ecklonia maxima along the South African coastline. The model incorporated buoyancy and sinking using site-specific morphological data. Findings revealed that the distribution of floating E. maxima is influenced by oceanographic conditions, and seasonal patterns were also evident. Mesoscale features played a vital role in kelp accumulation on the surface and seafloor and acted as barriers to dispersal. This study offers essential insights into kelp's role as an organic subsidy and provides numerical evidence for kelp's potential as a carbon sink, contributing to a better understanding of kelp ecosystems and their ecological functions. [ABSTRACT FROM AUTHOR]

Microbial infections are the most significant threats to human health, and there has been a recent increase in the number of deaths exclusively attributed to bacterial and fungal infections. The development of biofilms by bacterial and fungal pathogens has been identified as a key adaptive antimicrobial resistance (AMR) mechanism, in addition to intrinsic and extrinsic AMR. Various bioactive molecules have been isolated from marine organisms for use in biofilm therapies. These compounds are structurally complex, biocompatible, and economically viable. Studies have demonstrated that bioactive chemicals obtained from marine sources, marine-bioinspired nanomaterials, and marine polymer-antibiotic conjugates can control the biofilms and virulence factors of microbial pathogens. Microbial infections are major human health issues, and, recently, the mortality rate owing to bacterial and fungal infections has been increasing. In addition to intrinsic and extrinsic antimicrobial resistance mechanisms, biofilm formation is a key adaptive resistance mechanism. Several bioactive compounds from marine organisms have been identified for use in biofilm therapy owing to their structural complexity, biocompatibility, and economic viability. In this review, we discuss recent trends in the application of marine natural compounds, marine-bioinspired nanomaterials, and marine polymer conjugates as possible therapeutic agents for controlling biofilms and virulence factors. We also comprehensively discuss the mechanisms underlying biofilm formation and inhibition of virulence factors by marine-derived materials and propose possible applications of novel and effective antibiofilm and antivirulence agents. [ABSTRACT FROM AUTHOR]

Given the weak convergence, limited balance capacity, and optimization limitations observed in the Marine Predators Algorithm (MPA), which draws inspiration from the predatory behavior of marine organisms during evolutionary processes, this study introduces a Reinforcement Learning Marine Predators Algorithm (RLMPA). Firstly, based on the predatory characteristics at different stages, we have designed three location update strategies for search agents aimed at creating high-quality candidate solutions from three perspectives. In particular, ranking paired mutually beneficial learning is specifically designed to expand the scope of exploration to generate as many high-quality candidate solutions as possible for future generations. The Gaussian random walk learning is specifically designed to achieve better optimization in the transitional phase by adjusting the step-size control parameters, successfully completing the transition from exploration to local exploitation phase. Additionally, modified somersault foraging strategy is introduced to accelerate local convergence and perform more extensive local exploitation. Secondly, we integrate reinforcement learning into MPA and use Q-learning mechanism to adaptively select location update strategies. Agents fully utilize the collected information to evaluate the next action of the agents, coordinate the exploration phase and exploitation phase, and enhance the global optimization ability. Finally, compared with 10 competitive algorithms, RLMPA achieves better comprehensive performance in global optimization ability, search efficiency and convergence speed on 41 test functions and 5 practical engineering problems. In the Friedman rank sum tests, RLMPA achieves a preferable overall ranking, and has certain ascendant preponderances in solving practical problems with stability, effectiveness and robustness. [ABSTRACT FROM AUTHOR]

2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) is a widely used brominated flame retardant belonging to persistent organic pollutants (POPs). After being released into the marine environment, BDE-47 can cause a range of toxic effects on marine organisms through bioaccumulation, biomagnification, and intergenerational transmission. These effects include lethality, impaired motility, photosynthetic toxicity, immune damage, liver toxicity, developmental impairments, and reproductive toxicity. This article reviews the latest research progress on the toxic effects and molecular mechanisms of BDE-47 mentioned above. The primary mechanisms underlying its toxicity include oxidative stress, DNA damage, cellular apoptosis, impaired metabolism, and activation of the MAPK signaling cascade. [ABSTRACT FROM AUTHOR]

Dalian Island, located in the northwest of Pingtan County, Fujian Province, China, has been an important junction on the Maritime Silk Road since the Tang dynasty. This study focuses on sauce-glazed ceramic ware from the Song dynasty salvaged from the waters near Dalian Island Wharf. The composition, phase attributes, and microstructures of the marine organism remains attached to the ceramic ware were analyzed using an optical microscope, scanning electron microscope, and micro-Raman spectrometer to investigate the influence of marine organisms on the degradation of the ceramic ware. Long-term abrasion by sea wave-borne debris led to the increased surface roughness and wettability of the ceramic ware, facilitating the attachment of marine organisms. Differences in surface roughness between the inner and outer walls led to varying levels of biomass. Coralline algae secreted inducers to attract the larvae of macrofoulers. The attachment of different types of marine organisms had varying effects on the degradation of the ceramic ware. Firmly attached unitary organisms could alleviate the scouring of sea wave-borne debris and hinder the intrusion of foreign pollutants, thereby playing a 'bio-protective' role. In contrast, the group skeletons of modular organisms could reinforce the mechanically damaged surface but failed to block the intrusion of iron rust and other pollutants, resulting in chemical alterations of the glaze. Therefore, the specific species of the attached marine organisms should be considered in subsequent conservation efforts. [ABSTRACT FROM AUTHOR]

Biofouling, the accumulation of marine organisms on submerged surfaces, presents significant operational challenges across various marine industries. Traditional detection methods are labor intensive and costly, necessitating the development of automated systems for efficient monitoring. The study presented in this paper focuses on detecting biofouling on tidal stream turbine blades using camera-based monitoring. The process begins with dividing the video into a series of images, which are then annotated to identify and select the bounding boxes containing objects to be detected. These annotated images are used to train YOLO version 8 to detect biofouled and clean blades in the images. The proposed approach is evaluated using metrics that demonstrate the superiority of this YOLO version compared to previous ones. To address the issue of misdetection, a data augmentation approach is proposed and tested across different YOLO versions, showing its effectiveness in improving detection quality and robustness. [ABSTRACT FROM AUTHOR]

In‐situ observations indicate variations in stratified conditions over the coastal valley off the Sansha Bay in the northwestern Taiwan Strait across different years. However, dynamic processes and mechanisms governing the upwelling process over the valley, as influenced by stratification, are still unknown. By employing idealized numerical simulations, we demonstrate that compared to the unstratified case, the surface offshore flow intensifies, upwelling flux and net cross‐shore transport are enhanced, upwelling area expands, and the cross‐shore velocity structure is modified over the valley under stratified conditions. The primary factor controlling the vertical velocity within the valley is the relative vorticity change along a streamline (RVC). Further decomposition of the RVC reveals that the depth‐averaged alongshore velocity (v‾ $\overline{v}$) and the depth‐averaged alongshore gradient of vorticity (∂ξ‾/∂y $\partial \overline{\xi }/\partial y$) primarily modulate the magnitude and spatial distribution of the vertical velocity. The negative zone of the ∂ξ‾/∂y $\partial \overline{\xi }/\partial y$ expands in the valley, resulting in a larger upwelling area. The magnitude of the v‾ $\overline{v}$ in the upper layer is slightly enhanced. The combined influence of these two factors leads to increased upwelling flux in the valley under stratified conditions. The net upslope motion over the valley is intensified under stratified conditions. The augmented advection of relative potential vorticity, originating from the increased amplitude of coastal trapped lee waves, primarily contributes to the enhanced net cross‐shore transport in the valley. Plain Language Summary: The drop in sea surface temperature intensifies due to a strong upwelling process over a depression in the seafloor, called a coastal valley. The shape of this coastal valley, wind intensity, the effect of the Earth's rotation, and vertically varying density (stratification) conditions collectively influence the upwelling dynamics over a coastal valley. In this study, we specifically examine the impact of stratification on these dynamics, including the magnitude of upwelling and cross‐shore transport within the coastal valley. Using an idealized numerical model, we observe that under stratified conditions, both the magnitude of upwelling and cross‐shore transport within the coastal valley are enhanced compared to well‐mixed conditions. We analyze the underlying dynamical mechanisms. The original force for intensified upwelling is the coastal wave stimulated at the coastal valley. The intensified upwelling process on the downstream side of the coastal valley facilitates the transport of nutrients from the lower layer to the upper layer, which holds significant implications for marine organisms. Key Points: Upwelling flux and net cross‐shore transport in a coastal valley are enhanced under stratified conditionsDepth‐averaged alongshore velocity and alongshore gradient of vorticity modulate vertical velocityAugmented advection of relative potential vorticity under stratified conditions triggers enhanced net cross‐shore transport [ABSTRACT FROM AUTHOR]

ABSTRACT Coastal algal reef ecosystems, which are formed by the skeletal carbonate of crustose coralline algae (CCA), provide vital habitats for a diverse range of marine organisms and serve as valuable archives of long‐term environmental data. Despite the importance of these reef ecosystems, there is currently a lack of available information regarding the accretion rates of CCA in subtropical intertidal zones in the Taoyuan algal reef. We measured the vertical accretion and horizontal growth of CCA cultured in two aquaculture tanks over a 9‐month period. The vertical accretion and horizontal growth rate of CCA was approximately 0.29–0.43 and 5.5 μm·day−1 (the extrapolated annual value is equivalent to 0.11–0.16 and 2.0 mm·year−1, respectively). Newly colonized CCA had faster horizontal growth of approximately 110 μm·day−1 (equivalent to 40.2 mm·year−1). These results highlight the slow and gradual process of algal reef ecosystem formation in the subtropical intertidal zones. The CCA had a faster lateral growth rate as seen in the newly settled CCA. These findings contribute to our understanding of the overall growth dynamics of CCA. [ABSTRACT FROM AUTHOR]

Hydrostatic pressure is a dominant environmental cue for vertically migrating marine organisms but the physiological mechanisms of responding to pressure changes remain unclear. Here, we uncovered the cellular and circuit bases of a barokinetic response in the planktonic larva of the marine annelid Platynereis dumerilii. Increased pressure induced a rapid, graded, and adapting upward swimming response due to the faster beating of cilia in the head multiciliary band. By calcium imaging, we found that brain ciliary photoreceptors showed a graded response to pressure changes. The photoreceptors in animals mutant for ciliary opsin-1 had a smaller sensory compartment and mutant larvae showed diminished pressure responses. The ciliary photoreceptors synaptically connect to the head multiciliary band via serotonergic motoneurons. Genetic inhibition of the serotonergic cells blocked pressure-dependent increases in ciliary beating. We conclude that ciliary photoreceptors function as pressure sensors and activate ciliary beating through serotonergic signalling during barokinesis. [ABSTRACT FROM AUTHOR]

ABSTRACT A high circulating total cholesterol (TC) concentration increases the risk for atherosclerosis in the domestic dog. Intake of marine foods is associated with a lowering effect on circulating TC concentration in humans and rodents, but the reported effects of marine ingredients on the TC concentration in domestic dogs has not yet been reviewed. The main aim was to investigate the effects of consuming marine ingredients on the TC concentration in domestic dogs. A systematic literature search was performed using the databases PubMed, Web of Science and Embase, structured around the population (domestic dogs), intervention (source and type of marine ingredients, dose, duration), comparator (control diet) and the primary outcome (circulating TC). Articles were assessed for risk of bias using the SYRCLE's tool. A meta‐analysis was conducted in Review Manager v. 5.4.1 (the Cochrane Collaboration), comprising 12 articles with 243 dogs. Consumption of marine oils resulted in a significantly lower circulating TC concentration relative to comparator groups (mean difference −0.70 mmol/L, 95% CI (−1.21, −0.18), p = 0.008), with high statistical heterogeneity (I2 = 78%). The risk of bias is unclear since few of the entries in the SYRCLE's tool were addressed. We did not identify any studies using marine proteins or marine organisms other that fish. To conclude, intake of marine oils results in a lower TC concentration in dogs, thus reducing an important risk factor for atherosclerosis in canines. This study was registered at www.crd.york.ac.uk/PROSPERO/ as CRD42023396943. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX), which is found in various marine organisms, including pufferfish, shellfish, shrimp, crab, marine gastropods, and gobies, is an effective marine toxin and the cause of many seafood poisoning incidents. Owing to its toxicity and threat to public health, the development of simple, rapid, and efficient analytical methods to detect TTX in various food matrices has garnered increasing interest worldwide. Herein, we reviewed the structure and properties, origin and sources, toxicity and poisoning, and relevant legislative measures of TTX. Additionally, we have mainly reviewed the state-of-the-art progress of analytical methods for TTX detection in the past five years, such as bioassays, immunoassays, instrumental analysis, and biosensors, and summarized their advantages and limitations. Furthermore, this review provides an in-depth discussion of the most advanced biosensors, including cell-based biosensors, immunosensors, and aptasensors. Overall, this study provides useful insights into the future development and wide application of biosensors for TTX detection. [ABSTRACT FROM AUTHOR]

The Changjiang Estuary and adjacent East China Sea are well-known hypoxic aquatic environments. Eutrophication-driven hypoxia frequently occurs in coastal areas, posing a major threat to the ecological environment, including altering community structure and metabolic processes of marine organisms, and enhancing diversion of energy shunt into microbial communities. However, the responses of microbial communities and their metabolic pathways to coastal hypoxia remain poorly understood. Here, we studied the microbial communities collected from spatiotemporal samplings using metagenomic sequencing in the Changjiang Estuary and adjacent East China Sea. This generated 1.31 Tbp of metagenomics data, distributed across 103 samples corresponding to 8 vertical profiles. We further reported 1,559 metagenome-assembled genomes (MAGs), of which 508 were high-quality MAGs (Completeness > 90% and Contamination < 10%). Phylogenomic analysis classified them into 181 archaeal and 1,378 bacterial MAGs. These results provided a valuable metagenomic dataset available for further investigation of the effects of hypoxia on marine microorganisms. [ABSTRACT FROM AUTHOR]

Commercial overexploitation and climate change can alter the physiology and behavior of marine organisms, although intraspecific phenotypic responses to such changes can vary greatly depending on the environment, species, and severity of the stressor. Under the pace‐of‐life syndrome (POLS) hypothesis, behavior, physiology, and life‐history traits are linked, and thus, affected by selection targeting any aspect of organismal biology. However, these links are understudied in tropical marine fishes, and further work is needed to better understand the impacts of fisheries and climate change on wild stocks. Moreover, tropical regions have a greater reliance on fisheries; thus investigations should focus on species with substantial socioeconomic value to ensure benefits at the local level. This study aimed to address this need by measuring the behavior (boldness and activity), metabolism, and swimming performance (using a critical swim speed [Ucrit] test) of schoolmaster snapper Lutjanus apodus in Eleuthera, the Bahamas. We report a strong positive correlation between boldness and activity, high repeatability of these behavioral metrics, and two groupings that were consistent with “proactive” and “reactive” behavioral types. These behavioral types differed significantly in their swimming performance, with reactive individuals having a 13.1% higher mean Ucrit. In contrast, no significant differences were found in the measured metabolic parameters between behavioral types. This study is the first to investigate the intraspecific links between behavior and physiology in a snapper species, using the novel and ecologically relevant comparison of Ucrit with behavioral syndrome types. These data suggest that additional research is needed to better predict the success of proactive/reactive tropical fish if overexploited and as influenced by climate change. [ABSTRACT FROM AUTHOR]

Climate change is altering the distribution of marine organisms worldwide. This may, in turn, affect the overall structure and functioning of ecosystems, sometimes leading to low productive regimes. Pronounced shifts in distribution and migration have been observed for capelin (Mallotus villosus), one of the ecologically and commercially important species in the Arctic. This study attempts to discern whether a relationship existed between the altered capelin dynamics and the changing physical environmental conditions in the Iceland‐East Greenland‐Jan Mayen region. More specifically, three species distribution models were used to predict hindcasts (pre‐shift years 1993–2002) and nowcasts (post‐shift years 2003–2019) of capelin distribution based on relationships with temperature, salinity, current speed, net primary productivity, and bathymetry. The predicted probability of occurrence over these two time periods demonstrates that the changing environmental conditions have contributed to the modified distribution of the stock during its late feeding season in autumn and during the onset of spawning season in winter. The multi‐model approach used in this study has provided a solid statistical framework to describe the environmental niche of capelin and its potential responses to changing ocean climate. [ABSTRACT FROM AUTHOR]

Fungal infections are a significant threat to human health and the environment. The emergence of multidrug-resistant strains of fungi and the growing prevalence of azole resistance in invasive fungal infections exacerbate the problem, with efflux pumps being a major cause of antifungal resistance and a prime target for several counteractive strategies. In Candida albicans, the ATP-binding cassette superfamily transporter CaCdr1p is the predominant efflux pump involved in azole resistance. Marine organisms have unique phenotypic characteristics to survive in challenging environments, resulting in biologically active compounds. The cyclodepsipeptides unnarmicin A and C have shown promising results as inhibitors of rhodamine 6G efflux in cells expressing CaCdr1p. Herein, a series of unnarmicin analogues were designed and docked against a CaCdr1p efflux pump based on the cryogenic electron microscopy structure available to select the most promising compounds. Analogue 33 was predicted to be the best considering its high affinity for the efflux pump and pharmacokinetic profile. These results pave the way for further synthesis and in vitro biological studies of novel unnarmicins seeking a synergistic effect with fluconazole. [ABSTRACT FROM AUTHOR]

Zooplankton are important food organism in the marine ecosystem, and its community structure and population distribution reflect the productivity of the waters. In order to understand the interspecific relationship of the zooplankton community and the impact of changes in environmental factors on the niche differentiation of dominant species in the Bailanzi waters, basing on the zooplankton survey data in March and December of 2022 and June of 2023, we obtained the dominance index of zooplankton in this sea area through calculating the Levins niche width value and Pianka niche overlap value of the dominant species, and divided the niche types of the dominant species into broad niche species, medium niche species and narrow niche species. The redundancy analysis method was used to explore the main environmental factors affecting the niche differentiation of dominant species of zooplankton in Bailanzi waters. The results showed that there were 9 dominant species and all of them were wide ecological niche species in March 2022, 5 dominant species and all of them were wide ecological niche species in December 2022, and 6 dominant species, including 3 wide ecological niche species and 3 narrow ecological niche species, in June 2023. The niche overlap indexes of the dominant zooplankton species in March 2022 ranged from 0. 54 to 1. 00, and those in December 2022 ranged from 0. 60-0. 98 in March 2022, 0. 62-0. 99 in December 2022, and 0. 62-0. 99 in June 2023. Redundancy analysis showed that the main environmental factors affecting zooplankton distribution are temperature and salinity, followed by pH, dissolved oxygen （DO), ammonia nitrogen （NH3-N), dissolved inorganic phosphorus （DIP), dissolved inorganic nitrogen （DIN), chemical oxygen demand （COD). The research results are expected to provide basic information for an in-depth understanding of the interspecific relationships of zooplankton communities in Bailanzi waters and the adaptation mechanism of zooplankton to environmental changes, and provide a theoretical reference for high-quality marine ranch construction in this waters. [ABSTRACT FROM AUTHOR]

Lamellarins are natural products with a [3,4]-fused pyrrolocoumarin skeleton possessing interesting biological properties. More than 70 members have been isolated from diverse marine organisms, such as sponges, ascidians, mollusks, and tunicates. There is a continuous interest in the synthesis of these compounds. In this review, the synthetic strategies for the synthesis of the title compounds are presented along with their biological properties. Three routes are followed for the synthesis of lamellarins. Initially, pyrrole derivatives are the starting or intermediate compounds, and then they are fused to isoquinoline or a coumarin moiety. Second, isoquinoline is the starting compound fused to an indole moiety. In the last route, coumarins are the starting compounds, which are fused to a pyrrole moiety and an isoquinoline scaffold. The synthesis of isolamellarins, azacoumestans, isoazacoumestans, and analogues is also described. The above synthesis is achieved via metal-catalyzed cross-coupling, [3 + 2] cycloaddition, substitution, and lactonization reactions. The title compounds exhibit cytotoxic, multidrug resistance (MDR), topoisomerase I-targeted antitumor, anti-HIV, antiproliferative, anti-neurodegenerative disease, and anti-inflammatory activities. [ABSTRACT FROM AUTHOR]

Ciliated epithelia are widespread in animals and play crucial roles in many developmental and physiological processes. Epithelia composed of multi-ciliated cells allow for directional fluid flow in the trachea, oviduct and brain cavities. Monociliated epithelia play crucial roles in vertebrate embryos, from the establishment of left–right asymmetry to the control of axis curvature via cerebrospinal flow motility in zebrafish. Cilia also have a central role in the motility and feeding of free-swimming larvae in a variety of marine organisms. These diverse functions rely on the coordinated orientation (rotational polarity) and asymmetric localization (translational polarity) of cilia and of their centriole-derived basal bodies across the epithelium, both being forms of planar cell polarity (PCP). Here, we review our current knowledge on the mechanisms of the translational polarity of basal bodies in vertebrate monociliated epithelia from the molecule to the whole organism. We highlight the importance of live imaging for understanding the dynamics of centriole polarization. We review the roles of core PCP pathways and of apicobasal polarity proteins, such as Par3, whose central function in this process has been recently uncovered. Finally, we emphasize the importance of the coordination between polarity proteins, the cytoskeleton and the basal body itself in this highly dynamic process. [ABSTRACT FROM AUTHOR]

Biological data collection often overlooks short-term environmental variations, potentially leading to under- or over-estimation of species abundance and ineffective conservation actions. This study investigated the complex relationship between oceanic and meteorological processes and the short-term abundance patterns of two economically important fish species in Bahía Santa Elena, a tropical bay on the north Pacific coast of Costa Rica. Using two months of continuous acoustic telemetry data from 14 Colorado (Lutjanus colorado) and 16 Pacific dog (Lutjanus novemfasciatus) snappers, we investigated temporal and spatial changes in their relative abundance patterns. A wavelet analysis revealed dominant diurnal and semidiurnal frequencies in both species. The observed semi-diurnal and diurnal periodicity in fish abundance was correlated with water level and sunlight, particularly near the mangrove in the inner bay, suggesting that both species may be using these habitats for food and shelter during periods of high tide and at night. Understanding how oceanic and meteorological conditions influence the dynamics of marine organisms in coastal environments, particularly those that are often exploited by fisheries is crucial for developing effective management and conservation approaches. [ABSTRACT FROM AUTHOR]

The Early Triassic Nanzhang-Yuan'an Lagerstätte of Hubei Province, South China, preserves abundant marine reptiles in the uppermost part of the Jialingjiang Formation and provides detailed insights into marine organisms, including newly discovered and well preserved conodont clusters of the Family Ellisonidae. These conodont elements allow us to assess the bias introduced during the acquisition process. We examined conodont elements preserved on the bedding planes and those acquired after the acid-dissolving method to analyze their attributes and length distributions. We identified a biased preservation of different conodont elements related to their morphologies. After the acid-dissolving procedures, the bias increased, and all different elements were affected, with larger individuals being particularly prone to destruction. Among them, the P elements of Ellisonidae were the least affected, while the S elements were the most affected. This study further indicates that paleobiological interpretations based on fossil size or morphology could be obscured if the influence of post-mortem effect is ignored. [ABSTRACT FROM AUTHOR]

Microalgae are a substantial group of unicellular prokaryotic and eukaryotic marine organisms. Due to their high protein content of 50–70%, microalgae have the potential to become a sustainable alternative protein source, as well as aiding in the development of bioactive peptide-based nutraceuticals. A series of major steps are involved in the production of peptides from microalgae, which include the disruption of the microalgal cell wall, the hydrolysis of proteins, and the extraction or isolation of peptides derived from hydrolysis. Physical methods of cell wall disruptions are favored due to the ability to obtain high-quality protein fractions for peptide production. Bioactive peptides are protein fragments of two to twenty amino acid residues that have a beneficial impact on the physiological functions or conditions of human health. Strong scientific evidence exists for the in vitro antioxidant, antihypertensive, and anti-atherosclerotic properties of microalgal peptides. This review is aimed at summarizing the methods of producing microalgal peptides, and their role and mechanisms in improving cardiovascular health. The review reveals that the validation of the physiological benefits of the microalgal peptides in relation to cardiovascular disease, using human clinical trials, is required. [ABSTRACT FROM AUTHOR]

Organic modification can generally endow inorganic materials with novel and promotional characteristics to fit into new functionalities. In this paper, new cement-based composite materials, with Portland cement as the substrate and polyacrylamide (PAM, alone) and PAM/chitosan as the functional components mixed with cement (bulk modified) or served as the surface coating (surface modified), were prepared and engineered as sampling substrates for biofilm and coral co-culture. In comparison to the bulk modified substrate and pure cement material, the surface modified substrate showed a balanced mechanical property, considering both bending and compressive strengths and distinctive surface features toward facilitating biofilm and coral growth, as characterized by spectroscopic, morphological, mechanical, and biofilm and coral co-culture experiments. We, thus, believe that the as-prepared surface modified substrate has the very potential to be applied as a substitute/alternative for the conventional cement material in the construction and engineering of artificial facilities with ecological protection functions. [ABSTRACT FROM AUTHOR]

The rapid evolution of drug resistance is one of the greatest health issues of the 21st century. There is an alarming situation to find new therapeutic strategies or candidate drugs to tackle ongoing multi-drug resistance development. The marine environment is one of the prime natural ecosystems on Earth, the majority of which is still unexplored, especially when it comes to the microbes. A wide variety of bioactive compounds have been obtained from a varied range of marine organisms; however, marine bacteria-produced bacteriocins are still undermined. Owing to the distinct environmental stresses that marine bacterial communities encounter, their bioactive compounds frequently undergo distinct adaptations that confer on them a variety of shapes and functions, setting them apart from their terrestrial counterparts. Bacterially produced ribosomally synthesized and posttranslationally modified peptides (RiPPs), known as bacteriocins, are one of the special interests to be considered as an alternative to conventional antibiotics because of their variety in structure and diverse potential biological activities. Additionally, the gut microbiome of marine creatures are a largely unexplored source of new bacteriocins with promising activities. There is a huge possibility of novel bacteriocins from marine bacterial communities that might come out as efficient candidates to fight against antibiotic resistance, especially in light of the growing pressure from antibiotic-resistant diseases and industrial desire for innovative treatments. The present review summarizes known and fully characterized marine bacteriocins, their evolutionary aspects, challenges, and the huge possibilities of unexplored novel bacteriocins from marine bacterial communities present in diverse marine ecosystems. [ABSTRACT FROM AUTHOR]

In the realm of underwater exploration and operations, soft robots exhibit considerable application potential due to their capacity for agile and complex deformations as well as their inherent compliance. These characteristics grant them excellent environmental adaptability and reduce damage to delicate samples and organisms. Nonetheless, existing underwater soft robots are primarily designed to mimic the movements of marine organisms or for specific functions, and little attention is paid to the camouflage ability. To address these challenges, in this study, a reconfigurable transparent soft robot with variable stiffness for underwater operations is presented. The design and fabrication methodology of the robot module is presented, followed by the kinematic analysis and stiffness characterization. Leveraging the proposed robot module, a soft manipulator and a soft gripper are designed for underwater operations. The soft manipulator excels in underwater pipeline detection and obstacle avoidance, while the soft gripper showcases considerable load‐bearing capacity (about 71 times its weight), making it suitable for tasks such as retrieving aquatic biological samples or garbage fishing. The proposed reconfigurable soft robot demonstrates robust camouflage capabilities, high environmental adaptability, and notable versatility, suggesting potential solutions to existing challenges in the field of underwater exploration. [ABSTRACT FROM AUTHOR]

During a ship's voyage, it is difficult to maintain its hull, and prolonged exposure to seawater can lead to the attachment of marine organisms, which can negatively impact the ship's speed. The original self-polishing copolymer was a tributyltin-containing paint used for applying two layers of protective coating onto a ship's bottom plate. According to International Maritime Organization (abbreviated as IMO) regulations, users are no longer allowed to use paints containing tributyltin. Therefore, manufacturers have developed a tributyltin-free paint, known as tin-free nanotechnology paint, which can be used as a replacement for the base coat on ship bottom plates. This study involves the use of a self-polishing copolymer spray and tin-free nanotechnology paint. A model coated with these two types of paint will be observed underwater to study the growth of marine organisms. Additionally, fuel consumption will be analyzed through underwater inspections and sea trials. Based on the experimental data, it is known that tin-free nanotechnology paint can significantly reduce the need for repairs in factories and greatly decrease maintenance costs when compared to self-polishing copolymers. [ABSTRACT FROM AUTHOR]

Jeju, the largest island in Korea, is the most economically important in terms of marine aquaculture. We investigated the marine viral composition adjacent to Jeju Island over four seasons in 2022 and sequenced DNA libraries extracted from samples in March, June, September, and December using Illumina HiSeq 2000. We obtained 212,402, 186,542, 235,441, and 224,513 contigs from the four-season samples, respectively. Among the identified metagenomes, bacteriophages were dominant in all the samples. Bacillus phage G was the dominant species in March and June, whereas Pelagibacter phage HTVC 008M was the dominant species in September and December. Additionally, the number of viruses that infected algal hosts was higher in December than in other seasons. Marine viruses appeared in all seasons and infected marine vertebrates such as fish. Functional analysis using MG-RAST revealed that cell wall- and capsule-related metabolism groups were activated in March and June, whereas virulence-, disease-, and defense-related metabolism groups were activated in September and December. Conclusively, this study revealed seasonal changes in marine viral communities in the sea adjacent to Jeju Island. Our data will be useful in identifying emerging marine viral pathogens and for further community studies on marine organisms. [ABSTRACT FROM AUTHOR]

Recent scientific investigations have highlighted concerning levels of microplastic contamination in marine ecosystems, posing significant risks to marine organisms and human populations. This study aimed to assess the prevalence of microplastics in water, sediment, and tissues of commercially important fish species along the Malabar coast in Northwest Kerala, India. Using Fourier transform infrared spectroscopy (FTIR), six predominant polymer types were identified, including HDPE, PET, and nylon. The investigation revealed notable abundances of transparent microplastic particles, measuring <1 mm in diameter, particularly in gastrointestinal and gill tissues, with gastrointestinal tissues exhibiting the highest concentration of microplastics. A diverse array of morphotypes, including fragments (48.08%), fibers (28.84%), filaments (19.23%), and granules (3.85%), were observed within the coastal zone. The study implicates various sources of contamination, such as direct discharges, runoff, and inadequate wastewater management practices, contributing to the substantial presence of microplastics in coastal environments. In light of these findings, the study emphasizes the urgent need for the implementation of effective regulatory measures to mitigate plastic pollution in marine ecosystems. These results underscore the critical importance of proactive intervention to safeguard the health of marine ecosystems and human populations in coastal regions. [ABSTRACT FROM AUTHOR]

Plastic pollution represents a global environmental issue. Awareness of plastic pollution in marine organisms increased strongly during the last decades, including chondrichthyans. Due to a lack of a broad and comprehensive view of this global issue in chondrichthyans, we synthesized the 48 publications covering 54 species since 2002, and employed bibliometric analysis and data exploration to summarize the historical progression of the development, characteristics of plastics in chondrichthyans and evaluate their potential impacts across various regions, habitats, and Red List categories. The bibliometric analysis revealed that the investigation of plastic distribution in demersal sharks inhabiting the nearshore areas of the Mediterranean and northeastern Atlantic Ocean is a major research focus. Based on the current evaluation, plastics have been ubiquitously discovered within sharks, skates, and rays; however, only less than 5% of chondrichthyans worldwide have been investigated. Among these, 25 species are classified under one of the three threatened categories (critically endangered, endangered or vulnerable), according to IUCN Red List. The average abundance (all specimens) and load (specimens that contained plastics) in chondrichthyans were 2.86 ± 7.71 items/individual and 4.91 ± 9.39 items/individual, respectively. Plastic abundance/load is not influenced by the sampling regions, habitats, or Red List categories; however, higher records were found in the endangered and near threatened species. The plastics are predominantly fibrous in shape, with blue and black being the predominant colors, along with polypropylene and polyethylene in polymer type. Notably, inconsistencies in sampling, processing, and identification methods across studies might impeded the integration and comparison of data. This review highlights the potential implications of plastic pollution from chondrichthyans on biodiversity conservation and emphasizes the necessity to consider intra- and inter-specific variations in biometric and ecological characteristics, as well as establish standardized protocols to facilitate effective comparisons in contamination dynamics between studies of chondrichthyans. [ABSTRACT FROM AUTHOR]

Fungal infections are a significant threat to human health and the environment. The emergence of multidrug-resistant strains of fungi and the growing prevalence of azole resistance in invasive fungal infections exacerbate the problem, with efflux pumps being a major cause of antifungal resistance and a prime target for several counteractive strategies. In Candida albicans, the ATP-binding cassette superfamily transporter CaCdr1p is the predominant efflux pump involved in azole resistance. Marine organisms have unique phenotypic characteristics to survive in challenging environments, resulting in biologically active compounds. The cyclodepsipeptides unnarmicin A and C have shown promising results as inhibitors of rhodamine 6G efflux in cells expressing CaCdr1p. Herein, a series of unnarmicin analogues were designed and docked against a CaCdr1p efflux pump based on the cryogenic electron microscopy structure available to select the most promising compounds. Analogue 33 was predicted to be the best considering its high affinity for the efflux pump and pharmacokinetic profile. These results pave the way for further synthesis and in vitro biological studies of novel unnarmicins seeking a synergistic effect with fluconazole.

Background: Recent studies have elucidated the quorum-sensing mechanisms, biofilm formation, inter-pathogen interactions, and genes related to oral pathogens. This review aims to explore the recent expansion of drug targets against oral pathogens and summarize the current research on novel antibiotic substances derived from marine organisms that target oral pathogens. Methods: A comprehensive literature review summarized the novel mechanisms pertaining to quorum-sensing signal transmission systems, biofilm formation, and metabolite exchange in oral pathogens. The amino acid sequences of the 16 proteins identified as potential drug targets were systematically classified and compared across various oral microorganisms. Results: Through a literature review, we identified nine studies researching quorum sensing signaling inhibitors targeting oral pathogens. A comparison of the amino acid sequences of 16 potential drug targets in oral microorganisms revealed significant differences between oral pathogens and beneficial oral symbiotic microorganisms. These findings imply that it is possible to design drugs that can bind more selectively to oral pathogens. Conclusion: By summarizing the results of recent research on the signaling mechanisms that cause pathogenicity, new drug targets against oral pathogens were proposed. Additionally, the current status of developing new antibiotics for oral pathogens using recently developed quorum sensing inhibitors and natural products derived from marine organisms was introduced. Consequently, marine natural products can be used to develop drugs targeting new proteins in oral pathogens.

Fourier-transform near-infrared spectroscopy (FT-NIRS) has recently been used to reduce the processing time for estimates of annual age in several fish species. The present study represents the first application of this technique to marine organisms from the European waters. Atlantic horse mackerel (Trachurus trachurus) from the central Mediterranean Sea was selected for its ecological role, its socioeconomic value, and because its age is regularly estimated by otolith reading under a stereomicroscope for stock assessment purposes. Absorption spectra of the whole otoliths were acquired by FT-NIRS across a multiyear dataset, obtained during acoustic surveys carried out in different regions of the central Mediterranean Sea. The acquired spectra were processed to optimize calibration models to predict age. The best linear models obtained by the optimizing procedure predicted age successfully with a coefficient of determination of 0.95-0.96, mean squared error of 0.5 years, and bias <0.03 years. Although regional calibration models were also obtained separately, the models with all regions combined appeared much more robust and encompassing the whole age range, suggesting its usefulness for the entire spatial distribution range considered in the preset study. The use of FT-NIRS allowed to successfully predict age for horsemackerel between the ages 1 and 14, with similar or better precision (and bias) of the traditional methods, also increasing the standardization by repeatability of age assignments. The preliminary results obtained by this study encourage further effort to fine-tune the calibration model for new species, in order to apply a precise, rapid, costeffective method for stock assessment purposes of Mediterranean fish resources. [ABSTRACT FROM AUTHOR]

The International Maritime Organization has adopted a revision to the 2023 International Maritime Organization biofouling guidelines and has been discussing the development of guidelines for evaluating the efficacy of inwater cleaning systems. In hull cleaning, which involves aquatic invasive species removal, capture is considered very important in preventing the release of by-products. However, capture efficacy is difficult to evaluate due to the absence of unified evaluation guidelines or standardized methods. Here, we describe a new test method for evaluating the capture efficacy of in-water cleaning systems, using artificial barnacles that simulate the physical characteristics of actual barnacles. The test was designed to evaluate the impact of in-water cleaning on biocide release and biofouling organisms in the marine environment. We used a test plate with artificial barnacles attached to evaluate the capture efficacy with respect to the fouling rating. This test overcomes limitations in the evaluation of the capture efficacy of in-water cleaning systems and provides a reference for the development of more comprehensive tests and in-water cleaning regulation in the future. [ABSTRACT FROM AUTHOR]

Marine organisms continually adapt their physiology and behaviour to temporal variations in their environment, resulting in diurnal rhythmic behaviour, particularly when foraging. In delphinids, these rhythms can be studied by recording echolocation clicks, which can provide indicators of foraging activity. The foraging rhythms of delphinids and their relationship to temporal parameters are poorly documented and most studies so far have used moored passive acoustic systems. The present study provides, for the first time, information on the activity rhythms of delphinids investigated in relation with temporal variables at a basin scale from a moving platform, in the western and central Mediterranean Sea. We used passive acoustic recordings collected by hydrophones towed along transect lines during the ACCOBAMS Survey Initiative in the summer 2018. We extracted variables that may influence daily and monthly rhythms, including time of day, lunar cycle, lunar illumination and sea state and fitted generalised additive models. The nycthemeral and lunar cycles were the two main factors influencing dolphin activity rhythms. Echolocation activity was predominant at night, with a maximum of 0.026 acoustic events per minute at 21:00/22:00 compared to as few as 0.0007 events per minute at 11:00. These events were also more frequent during the third quarter of the moon; 0.033 acoustic events on day 22 of the lunar cycle as opposed to 0.0008 on day 8 of the lunar cycle, corresponding to the first quarter of the moon. Variations in the echolocation activity of delphinids in the Mediterranean Sea could reflect variation in their foraging effort and be related to prey density, composition, accessibility and catchability within dolphin foraging depth range. These results should also improve interpretation of passive acoustic monitoring data. [ABSTRACT FROM AUTHOR]

Introduction: In recent decades, Caribbean coral reefs have lost many vital marine species due to diseases. The well-documented mass mortality event of the long-spined black sea urchin Diadema antillarum in the early 1980s stands out among these collapses. This die-off killed over 90% of D. antillarum changing the reefscape from coral to algal-dominated. Nearly 40 years later, D. antillarum populations have yet to recover. In early 2022, a new mortality event of D. antillarum was reported along the Caribbean, including Puerto Rico. Methods: This study identifies the gut microbiota changes associated with the D. antillarum during this mortality event. It contrasts them with the bacterial composition of gut samples from healthy individuals collected in 2019 by using 16S rRNA sequencing analyses. Results: Notably, the die-off group's core microbiome resembled bacteria commonly found in the human skin and gut, suggesting potential anthropogenic contamination and wastewater pollution as contributing factors to the 2022 dysbiosis. The animals collected in 2022, especially those with signs of disease, lacked keystone taxa normally found in Diadema including Photobacterium and Propionigenium. Discussion: The association between human microbes and disease stages in the long-spined urchin D. antillarum, especially in relation to anthropogenic contamination, highlights a complex interplay between environmental stressors and marine health. While these microbes might not be the direct cause of death in this species of sea urchins, their presence and proliferation can indicate underlying issues, such as immune depletion due to pollution, habitat destruction, or climate change, that ultimately compromise the health of these marine organisms. [ABSTRACT FROM AUTHOR]

The richness of Brazilian biodiversity translates into a valuable collection of molecules with biological properties that range from ecological functions to pharmacological properties. For over 25 years, the Nucleus of Bioassays, Biosynthesis, and Ecophysiology of Natural Products (NuBBE) has conducted extensive investigations into the chemical entities of numerous plant and microorganism species, resulting in the discovery of over a thousand natural compounds spanning various chemical classes (such as shikimate derivatives, phenylpropanoids, terpenoids, alkaloids, and peptides). The research goals within the natural products field encompass phytochemical studies, investigations of endophytic fungi and marine organisms, biosynthetic studies, medicinal chemistry, and the development of innovative methodologies. This comprehensive review article aims to offer valuable insights into the multifaceted research endeavors conducted in NuBBE. In this way, accomplishments, perspectives, and opportunities for advancing natural products research in Brazil are highlighted, seeking to inspire and motivate other research groups in the field of natural products-especially those located in emerging countries with rich biodiversity. [ABSTRACT FROM AUTHOR]

The number of studies investigating the effects of ocean acidification on marine organisms and communities increases every year. Results are not easily comparable since the carbonate chemistry and ancillary data are not always reported in similar units and scales and are not calculated using similar sets of constants. To facilitate data comparison, a data compilation hosted by the PANGAEA Data Publisher was initiated in 2008 and is updated on a regular basis (10.1594/PANGAEA.962556; Ocean Acidification International Coordination Centre (OA-ICC), 2023). By November 2023, a total of 1501 datasets (over 25 million data points) from 1554 papers had been archived. To easily filter and access relevant biological response data from this compilation, a user-friendly portal (https://oa-icc.ipsl.fr , last access: 9 November 2023) was launched in 2018. Here, we present an update of this data compilation since its second description by Yang et al. (2016) and provide an overview of the OA-ICC portal for ocean acidification biological response data, launched in 2018. Most of the study sites from which data have been archived are in the North Atlantic Ocean, North Pacific Ocean, South Pacific Ocean, and Mediterranean Sea, while polar oceans are still relatively poorly represented. Mollusca and Cnidaria are still the best-represented taxonomic groups. The biological processes most reported in the datasets are growth and morphology. Other variables that can potentially be affected by ocean acidification and are often reported include calcification/dissolution, primary production/photosynthesis, and biomass/abundance. The majority of the compiled datasets have considered ocean acidification as a single stressor, but their relative contribution has decreased from 68 % before 2015 to 57 % today, showing a clear tendency towards more data archived from multifactorial studies. [ABSTRACT FROM AUTHOR]

Target strength (TS) is an acoustic property of individual marine organisms and a critical factor in acoustic resource assessments. However, previous studies have primarily focused on measuring TS at narrowband, typical frequencies, which cannot meet the requirements of broadband acoustic technology research. Additionally, for marine fish, conducting in situ TS measurements is challenging due to environmental constraints. Rapidly freezing and preserving fish samples for transfer to the laboratory is a common method currently used. However, the impact of freezing preservation during transportation on the swimbladder morphology and TS of swimbladder-bearing fish remains unclear. This study investigated the differences in swimbladder morphology and TS of Chub mackerel (Scomber japonicus) before and after freezing. Then, we compared different TS measurement methods through ex situ TS measurements (45–90 kHz, 160–260 kHz) and the Kirchhoff-ray mode model (KRM) simulations (1–300 kHz) and studied the broadband scattering characteristics of Chub mackerel based on the KRM model. The results showed that the morphology of the swimbladder was reduced after freezing, with significant changes in swimbladder height and volume. However, the trends of TS were not consistent and the changes were small. The difference between the KRM model and ex situ measurements was −0.38 ± 1.84 dB, indicating good applicability of the KRM. Based on the KRM results, the TS exhibited significant directivity, with fluctuations gradually decreasing and stabilizing as frequency increased. In the broadband mode, the relationship between TS and body length (L) of Chub mackerel was TS = 20log(L) − 66.76 (30 > L/λ >10). This study could provide a reference for acoustic resource estimation and species identification of Chub mackerel in the Northwest Pacific Ocean. [ABSTRACT FROM AUTHOR]

Evaluation of stable carbon (δ13C) and nitrogen (δ15N) isotopes in marine organisms over time addresses how environmental variability (e.g., El Niño or The Blob) affects habitat use and food resources, respectively. This work focuses on the impact of warm events in the Northeastern Pacific Ocean on the foraging strategies of adult female northern elephant seals (Mirounga angustirostris; NES) from the San Benito Archipelago in Mexico during their post-molting migration, through isotopic variability in pups as maternal indicators. Analysis of δ15N and δ13C was carried out on lanugo samples (n = 311) of weaned pups from the 2013–2017, 2019, and 2022–2023 breeding seasons and correlations with sea surface temperature (SST) anomalies of the potential foraging areas of female NES from the San Benito Archipelago were investigated. Isotopic niches showed high overlap throughout most of the study period, suggesting a limited impact of SST anomalies on their foraging strategies. However, values of δ15N and δ13C differed in 2014, 2018, and 2021 relative to other years, suggesting shifts to distant regions in latitude and longitude, and increased foraging effort during the post-molting migrations of these warm years. Findings demonstrate the flexibility and adaptive capacity of female NES relative to the warm events of the last decade. [ABSTRACT FROM AUTHOR]

Retinopathy of prematurity (ROP) is a vascular disorder affecting the retinas of preterm infants. This condition arises when preterm infants in incubators are exposed to high oxygen levels, leading to oxidative stress, inflammatory responses, and a downregulation of vascular endothelial growth factors, which causes the loss of retinal microvascular capillaries. Upon returning to room air, the upregulation of vascular growth factors results in abnormal vascular growth of retinal endothelial cells. Without appropriate intervention, ROP can progress to blindness. The prevalence of ROP has risen, making it a significant cause of childhood blindness. Current treatments, such as laser therapy and various pharmacologic approaches, are limited by their potential for severe adverse effects. Therefore, a deeper understanding of ROP's pathophysiology and the development of innovative treatments are imperative. Natural products from plants, fungi, bacteria, and marine organisms have shown promise in treating various diseases and have gained attention in ROP research due to their minimal side effects and wide-ranging beneficial properties. This review discusses the roles and mechanisms of natural products that hold potential as therapeutic agents in ROP management. [ABSTRACT FROM AUTHOR]