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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]

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]

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]

Ultraviolet radiation (UVR) is the photochemically most reactive waveband of incident solar irradiation. Despite high absorption in aquatic environments, UVR causes numerous biochemical, genetic, and cytotoxic effects in aquatic organisms. To counteract UVR stress, many of those species are able to synthesize, accumulate, or acquire UV-sunscreen compounds for photoprotection from their diet. The most abundant UV sunscreens in marine and freshwater organisms are mycosporine-like amino acids (MAAs), which exhibit high molar extinction coefficients in the UVR range along with a strong photo- and heat stability. In this study, we investigated the qualitative and quantitative MAA distribution patterns in the eyes of 39 fish species, mainly from the temperate northern hemisphere (Baltic Sea, Northern Atlantic), using state-of-the-art analytical methods. The fish eyes of the most investigated species (33 taxa) contained MAAs, between one and seven different compounds. The MAAs palythine, asterina-330, palythene, and usujirene were present (as previously reported), and three new compounds, aplysiapalythine A, porphyra-334, and shinorine, were identified. Total MAA concentrations covered a wide range from trace amounts to > 4.2 mg g-1 dry weight, thereby providing the first quantitative data on MAAs in fish eyes. The highest MAA contents were measured in Sprattus sprattus, which are comparable to those of intertidal red seaweeds. The trophic transfer of MAAs from primary producers via zooplankton to the fish is discussed, along with the localization in the fish eye as well as possible additional functions. [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]

Semilunar rhythms are found in numerous marine organisms, but the molecular mechanism and functional principles of endogenous circasemilunar clocks remain elusive. Here, we explore the connection between the free-running circasemilunar clock and the circadian clock in the marine midge Clunio marinus with three different chronobiological assays. First, we found that the free-running circasemilunar period of the adult emergence rhythm in C. marinus changes linearly with diel T-cycle length, supporting a day-counting mechanism. Second, under LD 6:6, periods of circasemilunar and circadian emergence were comparable to those under LD 12:12, indicating that the circasemilunar counter in C. marinus relies on endogenous circadian oscillations rather than external T-cycles. Finally, when desynchronizing the circadian clock with constant light, the free-running circasemilunar emergence rhythm disappeared as well, suggesting that it requires a synchronized circadian clock. These results oppose the long-held view that C. marinus' free-running circasemilunar clock operates independently of the circadian clock. In a broader evolutionary context, our results strengthen the idea that the circasemilunar clocks of dipterous insects are based on different functional principles compared to the circasemilunar or circalunar clocks of marine annelids and algae. These divergent clock principles may indicate multiple evolutionary origins of circasemilunar and circalunar clocks. [ABSTRACT FROM AUTHOR]

Aim: Quantify the contribution of environmental factors (water temperature, salinity and depth) and evolutionary history to varied skeletal mineralogy in calcifying marine organisms. Location: Global Ocean. Time period: Present. Major taxa studied: Order: Cheilostomatida; Phylum: Bryozoa. Methods: We employed X‐ray diffraction (XRD) to analyse the skeletal mineral composition of 872 individual colonies, representing 437 bryozoan species, in terms of calcite/aragonite ratios. We integrated these data with equivalent published data, thus reaching 981 species, and applied linear models (LMs), generalized linear models (GLMs) and phylogenetic generalized least squares models (PGLSs) to investigate the influences of temperature, salinity, depth and phylogenetic history on the mineralogy of nearly 1000 cheilostome bryozoan species. Results: Cheilostome bryozoans vary considerably in their skeletal mineral composition: in our dataset 65% of the species possess purely calcite skeletons, 15% exclusively employ aragonite and 20% exhibit mixed (i.e. calcite and aragonite) mineralogies. Temperature is the predominant measured environmental factor influencing bryozoan skeletal mineralogy, accounting for 20% of its variability across species, when phylogenetic relatedness is unaccounted for. Bryozoans in lower latitudes, characterized by higher seawater temperatures, have higher aragonite concentrations. By accounting for phylogenetic structure using a subset of 87 species for which we have topological information, 40% of the observed mineralogical variability could be attributed to present‐day temperature. In contrast, depth and salinity played minor roles, explaining less than 1% of the mineralogical variation each. Main conclusions: This study emphasizes the influence of evolutionary history on the mineralogical variability of calcifying organisms, even when it can be shown that a single environmental factor (temperature) explains a substantial amount of this variability. When confronted with changing temperature, calcifiers such as bryozoans are likely to respond in diverse ways, depending on the species, given their phylogenetic relatedness and the external conditions they meet. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVDs) affect the quality of life or are fatal in the worst cases, resulting in a significant economic and social burden. Therefore, there is an urgent need to invent functional products or drugs for improving patient health and alleviating and controlling these diseases. Marine bioactive peptides reduce and control CVDs. Many of the predisposing factors triggering CVDs can be alleviated by consuming functional foods containing marine biopeptides. Therefore, improving CVD incidence through the use of effective biopeptide foods from marine sources has attracted increasing interest and attention. This review reports information on bioactive peptides derived from various marine organisms, focusing on the process of the separation, purification, and identification of biological peptides, biological characteristics, and functional food for promoting cardiovascular health. Increasing evidence shows that the bioactivity and safety of marine peptides significantly impact their storage, purification, and processing. It is feasible to develop further strategies involving functional foods to treat CVDs through effective safety testing methods. Future work should focus on producing high‐quality marine peptides and applying them in the food and drug industry. [ABSTRACT FROM AUTHOR]

The frequency of riverine floods is predicted to increase in East Asia. However, the response of coastal hypoxia (<63 μmol L−1) to floods has not been well understood. In the summer of 2020, characterized by one of the most significant Changjiang water fluxes in three decades, we conducted a cruise during the flood period on the East China Sea inner shelf. Our observations revealed severe bottom hypoxia with a maximum spatial coverage of ∼11,600 km2 and a minimum dissolved oxygen concentration (DO) of 21 μmol L−1. In the surface layer, the relationships between salinity and nitrate, dissolved inorganic carbon (DIC) indicated significant organic matter production, validated by a high‐Chlorophyll‐a (Chl a) patch (>5 μg L−1). Furthermore, the significant relationship between apparent oxygen utilization and DIC of deep waters reveals that the organic matter decomposition primarily drove the hypoxia during the flood period. Episodic wind events also influenced bottom DO and DIC, by transporting surface waters to the deep. Multiple‐years data set shows that the average Changjiang nitrate flux during flood years is about 1.4 times that during non‐flood years. The flood waters mix with estuarine waters, forming the high‐nutrient plume waters, which expanded farther offshore during the flood period. While high turbidity remained confined to the inner estuary. Consequently, the high‐Chl a area significantly expanded, which significantly exacerbated the hypoxia. Plain Language Summary: Coastal waters are severely threatened by hypoxia, which impacts the growth, reproduction, and migration of marine organisms. Nutrient inputs from river basins are one of the major controlling factors of hypoxia in coastal oceans. The frequency and intensity of floods in river basins are projected to increase in the context of global warming in East Asia. However, the relationship between floods and coastal hypoxia is not well documented. The year 2020 witnessed lots of riverine flood events across Asian countries, which provided us with an excellent opportunity to reveal the influences of flood on hypoxia development on the shelf. In 2020, the August nitrate flux of Changjiang was 1.5 times higher compared to that in non‐flood years. We observed maximum hypoxic waters covering 11,600 km2 with a minimum DO of 21 μmol L−1 on the East China Sea inner shelf. Historical data showed that the floods led to the expansion of the high‐nutrient plume area, resulting in high biological production in the plume, and a nearly doubling of the hypoxia extent in the bottom waters. With the growing risk of intensive floods, hypoxia is likely to aggravate in coastal waters. Key Points: We observed a maximum hypoxia area of ∼11,600 km2, and a minimum dissolved oxygen of 21 μmol L−1 during the flood period in 2020Significant nitrate removal and surface Chlorophyll a exceeding 29 μg L−1 suggested intense biological production during the flood periodThe expansion of high‐Chl a plume area during flood periods surpasses that of non‐flood periods, contributing to hypoxia area increase [ABSTRACT FROM AUTHOR]

Steel monopile support structures for offshore wind turbines require protection from corrosion and consideration with respect to biofouling on their external and internal surfaces. Cathodic protection (CP) works effectively to protect the external surfaces of monopiles, but internally, byproducts from aluminum sacrificial anode CP (SACP) and impressed current CP (ICCP) induce acidification that accelerates steel corrosion. Through an 8-week sea water deployment of four steel pipes, this project investigated the effect of perforations on internal CP systems. Additionally, marine growth on the internal and external surfaces of the pipes was assessed. SACP and ICCP systems inside perforated pipes performed similarly to external systems at a lower current demand relative to internal systems in sealed pipes. The organisms that grew inside of the perforated SACP and ICCP pipes were similar, suggesting that the CP systems did not affect organism recruitment. The results of this study demonstrate the potential benefits of designing perforated monopiles to enable corrosion control while providing an artificial reef structure for marine organisms to develop healthy ecosystems. [ABSTRACT FROM AUTHOR]

Living in extreme environments, marine organisms face constant exposure to a range of stressors, such as high radiation levels, fluctuations in temperature, and oxidative stress. Understanding extremophile fishes is crucial because it gives us valuable insights into the biochemical, physiological, and developmental processes that govern life, by observing how they operate under natural stressors. Among the most fascinating adaptations is the existence of specialised enzymes and compounds that function as potent antioxidants, successfully counteracting reactive oxygen species' deleterious effects. In this review, we analysed the findings from several studies on Antarctic and deep-sea fish species, while highlighting the environmental stressors effects toward the antioxidant system. The antioxidant defences of the considered extremophile fishes have been extensively studied, but there is still much to learn to fully understand this complex system, while the relative research is still ongoing. Consequently, we are properly anticipating further advancements over the next few years about our understanding of crucial physiological processes that support cell survival. [ABSTRACT FROM AUTHOR]

Introduction: Global shipping has accelerated the spread of non-native species. Factors such as environmental filtering and interactions with local biota can affect invasion likelihood, yet their relative contribution to predicting invasion risk remains unresolved. To test how abiotic filters and an experimentally-derived measure of biotic resistance interact with propagule pressure, we developed an integratedmodel to evaluate their relative effects on invasion risk of marine biofouling organisms to different focal port regions. We predicted that environmental filtering impacts invasion risk when fewer but stronger connections are part of the network. Further, predation is a mechanism of biotic resistance, which can reduce invasion risk, with most pronounced effects predicted in the tropics that decline at higher latitudes. Methods: We examined shipping traffic and predation impact at three coastal bioregions spanning 47-degrees of latitude al range in the Northeast Pacific (Alaska, California, and Panama). We used vessel traffic databases to characterize propagule pressure and construct a worldwide port network of marine shipping routes and ports. Environmental resistance was estimated using temperature and salinity data from donor and recipient regions. We further used standardized predator exposure experiments to quantify predation impact on fouling community biomass as an estimate of potential for biotic resistance. We then expanded on existing models of relative invasion risk to incorporate the probability that propagules will survive predation by local predators and overcome environmental filtering to generate a predicted invasion risk for each port. Results: Environmental filtering in all regions and predation pressure in the tropics worked to reduce the invasion risk, resulting in markedly different cumulative risk profiles over time among regions. Discussion: In an increasingly connected world withmore vessel traffic, our results highlight thatwhile the number and distribution of shipping routes are important to understand risk, abiotic and biotic filters can modify model predictions. [ABSTRACT FROM AUTHOR]

Breast cancer is a major threat to women's health worldwide. Although the 5-year survival rate is relatively high, treating recurrent and metastatic breast cancer remains challenging. Existing anticancer drugs are often accompanied by adverse reactions; thus, there is an urgent need to explore safer and more effective treatment options. Marine natural compounds, especially alkaloids, are considered to be a potential treasure trove of new anticancer drugs due to their unique chemical structure and wide range of biological activities. A variety of marine alkaloids against breast cancer, including ecteinascidins, halichondrins, manzamines, and trabectedins, have opened new avenues for breast cancer treatment by employing multiple mechanisms, such as inducing cell apoptosis and autophagy, blocking cell cycle, inhibiting angiogenesis, targeting oncogene pathways, and inhibiting metastasis and invasion. Currently, Yondelis (trabectedin) has completed phase II clinical trials in patients with breast cancer and has shown certain efficacy. However, the clinical application of marine alkaloids still needs further research and development. This article deeply explores the mechanism of action of marine alkaloids against breast cancer and anticipates their clinical application prospects. With the deepening of research and the advancement of development, marine alkaloids are expected to bring new breakthroughs in breast cancer treatment. [ABSTRACT FROM AUTHOR]

An autonomous Zooglider navigated across the California Current Front into low salinity, minty waters characteristic of the California Current proper in both summers of 2019 and 2021. Diving to 400 m depth, Zooglider transited another near‐surface frontal gradient somewhat inshore. These frontal gradients were generally associated with changes in intensity, size composition, and Diel Vertical Migration responses of acoustic backscatterers. They were also associated with pronounced changes in zooplankton community composition, as assessed by a shadowgraph imaging Zoocam. Zoocam detected a decline in concentrations of copepods, appendicularians, and marine snow in the offshore direction, and an overall shift in community structure to a higher proportion of carnivorous taxa (and, in 2019, of planktonic rhizaria). No taxon was consistently elevated at all the peak frontal gradients, but appendicularians, copepods, and rhizarians sometimes showed front‐related increases in concentration. Such frontal gradient regions represent relatively abrupt transitions to different communities of planktonic organisms and suspended marine snow particles, with consequences for predator–prey relationships and the dominant vectors of particle export into subsurface waters. [ABSTRACT FROM AUTHOR]

Water molecules pose a significant obstacle to conventional adhesive materials. Nevertheless, some marine organisms can secrete bioadhesives with remarkable adhesion properties. For instance, mussels resist sea waves using byssal threads, sandcastle worms secrete sandcastle glue to construct shelters, and barnacles adhere to various surfaces using their barnacle cement. This work initially elucidates the process of underwater adhesion and the microstructure of bioadhesives in these three exemplary marine organisms. The formation of bioadhesive microstructures is intimately related to the aquatic environment. Subsequently, the adhesion mechanisms employed by mussel byssal threads, sandcastle glue, and barnacle cement are demonstrated at the molecular level. The comprehension of adhesion mechanisms has promoted various biomimetic adhesive systems: DOPA-based biomimetic adhesives inspired by the chemical composition of mussel byssal proteins; polyelectrolyte hydrogels enlightened by sandcastle glue and phase transitions; and novel biomimetic adhesives derived from the multiple interactions and nanofiber-like structures within barnacle cement. Underwater biomimetic adhesion continues to encounter multifaceted challenges despite notable advancements. Hence, this work examines the current challenges confronting underwater biomimetic adhesion in the last part, which provides novel perspectives and directions for future research. [ABSTRACT FROM AUTHOR]

In this study, a comparison of the concentrations of eight heavy metals (including Fe, Mn, Cu, Zn, Cr, As, Cd, and Hg) was conducted between wild and cultured Oplegnathus fasciatus. Significant differences in the concentrations of Zn, Cd, As, and Hg were observed between wild and cultured Oplegnathus fasciatus. The results showed that the mean Zn concentration was significantly higher in cultured Oplegnathus fasciatus (3.051 ± 0.738 mg/kg) when compared to its wild counterpart (2.512 ± 0.407 mg/kg). In contrast, the mean Cd concentration was found to be lower in the cultured Oplegnathus fasciatus (0.001 ± 0.0007 mg/kg) than in the wild ones (0.003 ± 0.003 mg/kg). Likewise, the wild samples demonstrated a higher mean As concentration (1.494 ± 0.659 mg/kg) than the cultured samples (0.594 ± 0.215 mg/kg). Lastly, it was noted that the mean Hg concentration was considerably higher in the cultured Oplegnathus fasciatus (0.042 ± 0.016 mg/kg) than in the wild specimens (0.014 ± 0.011 mg/kg). Pollution levels and health risks were evaluated using the single-factor pollution index (SFI), metal pollution index (MPI), and health risk assessment methods. The results showed that, for Cu, Zn, Cr, and Cd, both wild and cultured Oplegnathus fasciatus had SFI values below 1 compared to the marine organism quality standards. The MPI values for wild and cultured Oplegnathus fasciatus were 0.188 ± 0.051 and 0.172 ± 0.054, respectively, both far below the safety limit of 2 for pollution-free aquatic products. The Hazard Index (HI) for wild and cultured Oplegnathus fasciatus were below 1, indicating no health risks from long-term consumption. A discriminant analysis, based on Zn, Cd, As, and Hg concentrations, distinguished wild from cultured Oplegnathus fasciatus with a 96.0% accuracy, remaining stable at over 94.9% upon cross-validation. These findings accurately evaluate that there is no risk to human health from consuming Oplegnathus fasciatus, which is significant in safeguarding public health. [ABSTRACT FROM AUTHOR]

The "hologenome" concept is an increasingly popular way of thinking about microbiome-host for marine organisms. However, it is challenging to track hologenome dynamics because of the large amount of material, with tracking itself usually resulting in damage or death of the research object. Here we show the simple and efficient holo-2bRAD approach for the tracking of hologenome dynamics in marine invertebrates (i.e., scallop and shrimp) from one holo-2bRAD library. The stable performance of our approach was shown with high genotyping accuracy of 99.91% and a high correlation of r > 0.99 for the species-level profiling of microorganisms. To explore the host-microbe association underlying mass mortality events of bivalve larvae, core microbial species changed with the stages were found, and two potentially associated host SNPs were identified. Overall, our research provides a powerful tool with various advantages (e.g., cost-effective, simple, and applicable for challenging samples) in genetic, ecological, and evolutionary studies. Holo-2bRAD allows cost-effective and stable tracking of hologenome dynamics in marine invertebrates, also for difficult samples. It was used to identify two host SNPs and a change of core microbial species in mass mortality events of bivalve larvae. [ABSTRACT FROM AUTHOR]

Contamination by metals poses a significant threat to marine ecosystems and the health of marine organisms, including cetaceans. This study aimed to assess the concentrations of some metal and metalloids in the skin of bottlenose dolphins (Tursiops truncatus) from the Yucatan Peninsula in Mexico using Flame Atomic Absorption (FAA) spectrometry. A total of 41 skin samples were collected, comprising 22 samples from Yucatán in the Gulf of Mexico and 19 samples from Chetumal Bay in the Caribbean. The results of our analysis revealed the presence of various elements in the skin of bottlenose dolphins from coastal waters in the Yucatan Peninsula. Among the detected metals, zinc (Zn), iron (Fe), and arsenic (As) exhibited notable concentrations, with the order of abundance being Zn > Fe > As > Cu > Cr > Cd > Ni. The elevated concentrations of Zn and Fe suggest potential exposure and accumulation of these metals in the studied dolphin population. Interestingly, measurable concentrations of lead (Pb) and manganese (Mn) were not detected in the skin samples, indicating either low levels or the absence of their accumulation in the studied dolphin populations. The absence of measurable Pb concentrations is particularly encouraging as Pb is known to have detrimental effects on marine organisms and is commonly associated with anthropogenic activities. This study provides valuable insights into the metal contamination status in bottlenose dolphins from the Yucatan Peninsula, Mexico. The notable concentrations of Zn, Fe, and As raise concerns about potential health risks to these charismatic marine mammals. Further research is warranted to investigate the sources and pathways of heavy metal exposure in this population and to understand the potential consequences of such exposure on the health and well-being of bottlenose dolphins in the Yucatan Peninsula. [ABSTRACT FROM AUTHOR]

Organisms often swim through density-stratified fluids. Here, we investigate the dynamics of active particles swimming in fluid density gradients and report theoretical evidence of taxis as a result of these gradients (densitaxis). Specifically, we calculate the effect of density stratification on the dynamics of a force- and torque-free spherical squirmer and show that density gradients induce reorientation that tends to align swimming either parallel or normal to the gradient depending on the swimming gait. In particular, swimmers that propel by generating thrust in the front (pullers) rotate to swim parallel to gradients and hence display (positive or negative) densitaxis, while swimmers that propel by generating thrust in the back (pushers) rotate to swim normal to the gradients. This work could be useful to understand the motion of marine organisms in ocean or be leveraged to sort or organize a suspension of active particles by modulating density gradients. [ABSTRACT FROM AUTHOR]

Summary: Oceans cover over 70% of the Earth's surface and provide home to structurally diverse marine organisms. These creatures contribute to more than half of the biodiversity of the world and produce several bioactive molecules, including peptides. In the past years, scientific research has been focused on the compositions, sequences and structural features of marine‐derived peptides. Based on their amino acid sequences, they have demonstrated a wide range of biological functions, including antithrombotic, antihypertensive, anticancer, antioxidant, antimicrobial, antiageing, anti‐inflammatory, immunomodulatory and other multifunctional activities that are based on their structure, hydrophobicity, binding affinity, charge and other factors. This review focuses on novel techniques used to produce marine peptides and explores the structure–function relationships of these peptides derived from representative phyla, namely Cnidaria, Annelida, Mollusca, Arthropoda, Chordata, Echinodermata and Porifera. Furthermore, notable considerations regarding the structure–function basis of marine peptide applications are discussed. [ABSTRACT FROM AUTHOR]

The taxonomic composition, abundance, diversity and spatial distribution of phytoplankton and zooplankton, as well as the prevailing hydrographic conditions, were examined in the Whin Estuary, which is considered one of the most pristine and productive coastal ecosystems of Ghana, which is located on the Gulf of Guinea. Hydrographic and plankton variables were determined along the gradient of the estuary between March and July 2022 across two seasons and tidal periods. A total of 50 genera of phytoplankton and 27 genera of zooplankton were recorded across the two seasons and sampling periods. Diatoms and copepods dominated the plankton communities across the estuary. Plankton genera such as Navicula, Nitzschia, Thalassiosira, Cyclops, Paracalanus and Temora were recorded across all the seasons and tidal periods, despite the varying hydrographic conditions. The environmental variables varied across the seasons, tidal periods and sampling stations in the estuary. For instance, temperature, DO, transparency, and chlorophyll a varied significantly (p < 0.05) across both the seasons and tidal periods. pH values were significantly (p < 0.05) lower in the rainy season compared to the dry season. There was a strong salinity gradient across the estuary, with the upper reaches dominated by freshwater organisms, such as cladocerans and cyanobacteria, and the lower reaches by marine organisms, primarily diatoms and copepods. In sum, the results reported here are important as they highlight the distribution of plankton communities in a tropical estuarine ecosystem and can serve as a reference for the management of tropical brackish ecosystems. [ABSTRACT FROM AUTHOR]

Sea cucumbers, members of the echinoderm class Holothuroidea, are marine invertebrates with ecological significance and substantial commercial value. With approximately 1700 species, these organisms contribute to marine ecosystems through nutrient cycling and face various threats, including overfishing and habitat loss. Despite their importance, they are extensively exploited for diverse applications, from seafood to pharmaceuticals. This study investigates sea cucumbers' nutritional profile and bioactive elements, emphasizing their role as sources of essential compounds with potential health benefits. The demand for sea cucumbers, especially in dried form, is significant, prompting exploration into various drying techniques. Examining the global trade in sea cucumbers highlights their economic importance and the conservation challenges they face. Conservation efforts, such as awareness campaigns and international collaboration, are evaluated as essential steps in combating illicit trade and promoting the sustainable stewardship of sea cucumber populations. Practical Application: Around 1700 species of sea cucumbers were identified as vital ecological scavengers in the Holothuroidea class. High commercial value due to their health benefits, particularly their demonstrated inhibitory effect against various types of cancer. "Beche‐de‐mer" holds a 90% market share and is regarded as a luxury food item in Southeast Asian countries. Due to overexploitation, the species is classified as Schedule I under the Wildlife Protection Act (WPA) in India, prompting the implementation of a blanket ban on their harvesting to ensure its conservation. [ABSTRACT FROM AUTHOR]

Background: Microplastics (MPs) are pervasive pollutants in the marine environment, exhibiting persistence in coastal sediment over extended periods. However, the mechanism of their uptake by marine organisms and distribution in habitat is less understood. The objective of the present study was to investigate the presence of MP contamination in burrow sediment, feeding pellets, and tissue of Dotilla blanfordi in the Gulf of Kachchh, Gujarat State. Methods: A total of 500 g of burrow sediment, 100 g of feeding pellets, and body tissue of 10 resident D. blanfordi were pooled as one replica. Such seven replicas from each site were analyzed for MP extraction from three sites, including Asharmata, Mandvi, and Serena, located in the Gulf of Kachchh. The standard protocol was used during the analysis of the collected samples in order to isolate MPs. Results: The abundance of MP was found higher in burrow sediment, feeding pellets and tissue of D. blanfordi at study site Mandvi, followed by Serena and Asharmata. The abundance of MP was found higher in D. blanfordi tissue, followed by burrow sediment and feeding pellet. A significant variation was observed in MP abundance among burrow sediment, feeding pellets, and tissue. MPs with various shapes (fiber, film, and fragment), sizes (1–2, 2–3, 3–4, and 4–5 mm), and colors (blue, green, black, pink, purple, red transparent) were recorded from all the study sites. Polyurethane and polyvinyl chloride were recognized as the chemical profile of the extracted MPs. The current investigation revealed greater accumulation of MPs in D. blanfordi's tissues compared to sediment and pellets, suggesting a risk of MP contamination in marine benthic fauna with a greater rate of bioaccumulation. D. blanfordi plays a significant role as a structuring agent for MP distribution in the intertidal flat through burrowing activity. [ABSTRACT FROM AUTHOR]

Microplastics threaten the health of numerous marine organisms at all trophic levels. Currently, the topic is well studied among large predators. However, knowledge of microplastics present in organisms at lower trophic levels is poorly understood. The aim of this study was to assess the presence of microplastics within lower trophic level forage fishes. Four locations were sampled, classified into two categories based on human population: urban and non-urban. Five species were sampled: Striped Mullet (Mugil cephalus), Scaled Sardine (Harengula jaguana), Redfin Needlefish (Strongylura notata), Pinfish (Lagodon rhomboides), and Irish Pompano (Diapterus auratus). Of the 248 fish sampled, 99.6% contained microplastics, with a total of 2,126 pieces found in gastrointestinal tracts and livers. No significant difference in microplastics concentration among forage fish species was found. However, location had a significant effect on the frequency of microplastics found within the fishes, with the urban location near Miami, Florida having a higher frequency of occurrence compared with the other three sampled locations. This was the first study to assess microplastics within the forage fishes of southeastern Florida and provides further evidence that microplastics are pervasive throughout multiple trophic levels. [ABSTRACT FROM AUTHOR]

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Aiming at the problems of the underwater existence of some targets with relatively small size, low contrast, and a lot of surrounding interference information, which lead to a high leakage rate and low recognition accuracy, a new improved YOLOv7 underwater target detection algorithm is proposed. First, the original YOLOv7 anchor frame information is updated by the K-Means algorithm to generate anchor frame sizes and ratios suitable for the underwater target dataset; second, we use the PConv (Partial Convolution) module instead of part of the standard convolution in the multi-scale feature fusion module to reduce the amount of computation and number of parameters, thus improving the detection speed; then, the existing CIou loss function is improved with the ShapeIou_NWD loss function, and the new loss function allows the model to learn more feature information during the training process; finally, we introduce the SimAM attention mechanism after the multi-scale feature fusion module to increase attention to the small feature information, which improves the detection accuracy. This method achieves an average accuracy of 85.7% on the marine organisms dataset, and the detection speed reaches 122.9 frames/s, which reduces the number of parameters by 21% and the amount of computation by 26% compared with the original YOLOv7 algorithm. The experimental results show that the improved algorithm has a great improvement in detection speed and accuracy. [ABSTRACT FROM AUTHOR]

This study develops a YOLO (You Only Look Once)-based 3D perception algorithm for UVMS (Underwater Vehicle-Manipulator Systems) for precise object detection and localization, crucial for enhanced grasping tasks. The object detection algorithm, YOLOv5s-CS, integrates an enhanced YOLOv5s model with C3SE attention and SPPFCSPC feature fusion, optimized for precise detection and two-dimensional localization in underwater environments with sparse features. Distance measurement is further improved by refining the SGBM (Semi-Global Block Matching) algorithm with Census transform and subpixel interpolation. Ablation studies highlight the YOLOv5s-CS model's enhanced performance, with a 3.5% increase in mAP and a 6.4% rise in F1 score over the base YOLOv5s, and a 2.1% mAP improvement with 15% faster execution than YOLOv8s. Implemented on a UVMS, the algorithm successfully conducted pool grasping experiments, proving its applicability for autonomous underwater robotics. [ABSTRACT FROM AUTHOR]

Chamid bivalves are marine organisms that live in high-energy environments and are cemented to hard substrates. To avoid shell damage, the organisms form thick, densely ornamented shells. Shell material consists of aragonite, and the ornamentation may be either aragonitic or calcitic. The latter can be developed as scaly spines, rows of blades, or comarginal, radial arched lamellae. We investigated biological crystal morphology and mode of assembly of Chama arcana and Chama gryphoides shells. Structural characteristics were obtained from electron backscatter diffraction (EBSD) measurements, complemented with laser confocal and BSE imaging. We found a wide range of crystal morphologies and sizes, ranging from irregularly shaped calcite and/or aragonite prisms to tiny and thin aragonite laths. We observed four different modes of crystal assembly patterns: 1. strongly interlocked dendritic calcite units forming the ornamentation blades; 2. aragonite laths arranged to lamellae forming the outer shell layer, the layer adjacent to the calcite; 3. aragonite laths arranged into blocks comprising inner shell layers or aragonitic ornamentations; and 4. shell portions consisting of aragonite prisms, structured in size and crystal orientation, at muscle attachment sites. These four different types of crystal arrangements were observed for the shells of the investigated chamid species; however, they had slightly different strengths of structuring and slight variations in crystal organisation. Additionally, we observed unique microstructural features in Chama shells: We report ornamentation crystals resembling idiomorphic calcite and novel, twinned entities found at the changeover between the aragonitic layers. We highlight and discuss these differences and anomalies in this contribution. [ABSTRACT FROM AUTHOR]

Abstract Cardiovascular diseases (CVDs) affect the quality of life or are fatal in the worst cases, resulting in a significant economic and social burden. Therefore, there is an urgent need to invent functional products or drugs for improving patient health and alleviating and controlling these diseases. Marine bioactive peptides reduce and control CVDs. Many of the predisposing factors triggering CVDs can be alleviated by consuming functional foods containing marine biopeptides. Therefore, improving CVD incidence through the use of effective biopeptide foods from marine sources has attracted increasing interest and attention. This review reports information on bioactive peptides derived from various marine organisms, focusing on the process of the separation, purification, and identification of biological peptides, biological characteristics, and functional food for promoting cardiovascular health. Increasing evidence shows that the bioactivity and safety of marine peptides significantly impact their storage, purification, and processing. It is feasible to develop further strategies involving functional foods to treat CVDs through effective safety testing methods. Future work should focus on producing high‐quality marine peptides and applying them in the food and drug industry.

• 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]

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.

Fluorescence is a widespread phenomenon found in animals, bacteria, fungi, and plants. In marine environments fluorescence has been proposed to play a role in physiological and behavioral responses. Many fluorescent proteins and other molecules have been described in jellyfish, corals, and fish. Here we describe fluorescence in marine species, which we observed and photographed during night dives in the Banda Sea, Indonesia, and in the Red Sea, Egypt. Among various phyla we found fluorescence in sponges, molluscs, tunicates, and fish. Our study extends the knowledge on how many different organisms fluoresce in marine environments. We describe the occurrence of fluorescence in 27 species, in which fluorescence has not been described yet in peer-reviewed literature. It especially extends the knowledge beyond Scleractinia, the so far best described taxon regarding diversity in fluorescent proteins. [ABSTRACT FROM AUTHOR]

Many marine organisms broadcast gametes for external fertilization, thus conspecifics need to concentrate the time of gamete release through synchronization with environmental factors. We investigated the timing of spawning in two sea urchin species, Tripneustes gratilla and Toxopneustes pileolus, by assessing the spawning potential of individuals using both surveys and experiments in southern Taiwan from March to November 2010. We developed a new method to observe the spawning potential without sacrificing any individuals, defining those individuals‐initiated spawning within 30 min after 10 s of exposure to air as having the spawning potential. We discovered that the percentage of individuals with spawning potential, that is, the spawning ratios of the population, varied greatly from 0% to 80% in To. pileolus and from 0% to 50% in Tr. gratilla within the reproductive seasons. We evaluated the possibility of a lunar/semilunar rhythm of spawning ratios of the population and tested three environmental factors, that is, light intensity, tide, and temperature that could potentially affect the spawning potential of the sea urchins by experiments. Individuals with spawning potential were neither randomly nor evenly distributed among days but were aggregated on certain days; however, no lunar/semilunar rhythm of the spawning ratios was detected within the reproductive season. The possible role of the tidal factor within a day was not found in experiments in either species. However, when water temperature was >27°C in our surveys, significantly higher spawning ratios were observed in To. pileolus, but not in Tr. gratilla in the reproductive season. A further temperature experiment in To. pileolus supported the positive role of high temperature on the spawning ratios of individuals. In addition, To. pileolus was more likely to spawn during the day than at night, and the light/dark experiments suggested that the spawning potential was controlled by an endogenous biological clock rather than by the ambient light conditions directly. The lack of rhythmic pattern and yet concentrated spawning of these sea urchins may be adaptive to avoid predation. [ABSTRACT FROM AUTHOR]

Microplastics (plastic particles <5 mm) permeate aquatic and terrestrial ecosystems and constitute a hazard to animal life. Although much research has been conducted on the effects of microplastics on marine and benthic organisms, less consideration has been given to insects, especially those adapted to urban environments. Here, we provide a perspective on the potential consequences of exposure to microplastics within typical larval habitat on mosquito biology. Mosquitoes represent an ideal organism in which to explore the biological effects of microplastics on terrestrial insects, not least because of their importance as an infectious disease vector. Drawing on evidence from other organisms and knowledge of the mosquito life cycle, we summarise some of the more plausible impacts of microplastics including physiological, ecotoxicological and immunological responses. We conclude that although there remains little experimental evidence demonstrating any adverse effect on mosquito biology or pathogen transmission, significant knowledge gaps remain, and there is now a need to quantify the effects that microplastic pollution could have on such an important disease vector. [ABSTRACT FROM AUTHOR]

Microplastic (MP) particles (<5000 µm) pose a risk to many marine organisms. Globally, sponges are important suspension-feeding organisms that may be particularly vulnerable to MPs since many of these particles fall within their food size range. However, there has been little research on spatial variation in MP abundance in sponges. Here we examined MP abundance and spatial variation in sponges from Aotearoa New Zealand (NZ). We aimed to confirm the presence of potential microplastics (PMPs) in samples from 45 sponge samples across six species and three sites in the Wellington Harbour. Samples were digested with bleach, filtered, and analysed using fluorescent microscopy to quantify and measure PMPs. PMPs were present in every sponge sample with abundances between 207 ± 131 and 1893 ± 396 PMP particles g-1 (dry sponge weight). There were significant differences in PMP abundance between sites and between some species, but most of the variation was explained by site (40–53% vs. 4–24% of the variance). Our results suggest that PMP abundance in sponges is mainly explained by spatial variation in microplastic abundance rather than species identity. [ABSTRACT FROM AUTHOR]

Underwater target detection is an important method for detecting marine organisms. However, due to the image occlusion of underwater targets, blurred water quality, poor lighting conditions, small targets, and complex backgrounds, the detection of underwater biological targets has posed significant challenges. In the intricate underwater environment, the conventional feature extraction method has a few drawbacks, including imprecise feature extraction, sluggish detection speed, and inadequate robustness. Consequently, an underwater target detection method based on the enhanced You Only Look Once 7 (YOLOv7) is proposed in this study. The network architecture is reconstructed, and the Deformable Convolutional Network (DCN) modules replace some 3×3 convolutional blocks in the ELAN structure to offset sampling points and reduce background interference. Skip connections and 1 1 convolutional architecture are added to the DCN module to improve the model's perception of image details. In addition, Contextual Transformer 3 (COT3) is also incorporated to improve visual performance. Finally, to improve the detection efficiency of small objects, the CIoU loss function is finally replaced by the Normalized Wasserstein Distance (NWD) algorithm. The mAP of DCCN-YOLOv7 on the URPC dataset is 80.4%, according to the experimental results, 2.8% higher than the YOLOv7 network model that is used as a baseline. Furthermore, in contrast to the original YOLOv7 algorithm, the detection speed and accuracy are higher, making it more appropriate for target recognition underwater. [ABSTRACT FROM AUTHOR]

Cyclic pentapeptide compounds have garnered much attention as a drug discovery resource. This study focused on the characterization and anti-benign prostatic hyperplasia (BPH) properties of avellanin A from Aspergillus fumigatus fungus in marine sediment samples collected in the Beibu Gulf of Guangxi Province in China. The antiproliferative effect and molecular mechanism of avellanin A were explored in testosterone propionate (TP)-induced RWPE-1 cells. The transcriptome results showed that avellanin A significantly blocked the ECM–receptor interaction and suppressed the downstream PI3K-Akt signalling pathway. Molecular docking revealed that avellanin A has a good affinity for the cathepsin L protein, which is involved in the terminal degradation of extracellular matrix components. Subsequently, qRT-PCR analysis revealed that the expression of the genes COL1A1, COL1A2, COL5A2, COL6A3, MMP2, MMP9, ITGA2, and ITGB3 was significantly downregulated after avellanin A intervention. The Western blot results also confirmed that it not only reduced ITGB3 and FAK/p-FAK protein expression but also inhibited PI3K/p-PI3K and Akt/p-Akt protein expression in the PI3K-Akt signalling pathway. Furthermore, avellanin A downregulated Cyclin D1 protein expression and upregulated Bax, p21WAF1/Cip1, and p53 proapoptotic protein expression in TP-induced RWPE-1 cells, leading to cell cycle arrest and inhibition of cell proliferation. The results of this study support the use of avellanin A as a potential new drug for the treatment of BPH. [ABSTRACT FROM AUTHOR]

The growth and survival of marine organisms are influenced by environmental factors such as water temperature, salinity, and pH. Unsuitable environmental conditions may negatively impact marine organisms. The white leg shrimp (Litopenaeus vannamei), a euryhaline organism highly adapted to salinity, is a valuable species for aquaculture. This study examined the effects of water temperature, salinity, and pH on the health of postlarvae L. vannamei. Stress levels within the organisms were analyzed through the expression of a biomarker gene. Ferritin was selected as the biomarker gene for analysis. The experimental animal samples used were the hepatopancreas of L. vannamei postlarvae. The analysis was performed by qRT-PCR. The results showed that the adaptation of L. vannamei postlarvae to temperature was dependent on salinity. Under low-salinity conditions (5 psu), ferritin expression increased at 25 °C and 30 °C after 48 h of exposure; however, it decreased after 72 h of exposure. Under normal salinity conditions (27 psu), ferritin expression increased from 24 h to 72 h at water temperatures of 25 °C and 30 °C. These results indicate that low-salinity conditions may enable L. vannamei postlarvae to rapidly adapt to high temperatures. In conclusion, L. vannamei postlarvae adapt more efficiently to high temperatures under low-salinity conditions than that under high-salinity conditions. The results of this study could beneficially impact L. vannamei farming. [ABSTRACT FROM AUTHOR]

There has been a limited number of studies on the effects of harmful algal blooms (HABs) on natural rocky intertidal ecosystems. From mid-September to early November 2021, an unprecedented HAB caused by Karenia selliformis hit the Pacific coast of southeast Hokkaido, Japan, for the first time, causing massive mortalities among marine organisms. To clarify the immediate impacts of the HAB on the abundance of 10 rocky intertidal species in four functional groups (macroalgae, sessile invertebrates, molluscan grazers, and molluscan carnivores), we focused on two questions: (1) How did the HAB affect the abundance of each species differently at the regional scale? and (2) How did the impacts of the HAB on the abundance of each functional groups vary spatially, and was the spatial variation of the HAB impacts related to the spatial distribution of the cell density of HAB species? To study these issues, we compared census data for 17 years before the HAB and within one month after it for five shores on the southeast coast of Hokkaido. The results showed that two macroalgae species and all three molluscan grazer species declined significantly after the HAB. Moreover, the decrease in molluscan grazers was significantly correlated with cell density. These results suggest that the impacts of the HAB in southeast Hokkaido on the abundance of rocky intertidal organisms are highly variable depending on species and locality, presumably because of differences in species-specific tolerances to HAB toxins and the spatial variation in the density of the HAB organisms. [ABSTRACT FROM AUTHOR]