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Topic Review
UV-Filters Risk for Coastal Environments
Considering the rapid growth of tourism in recent years and the acknowledgement that exposure to solar UV radiation may cause skin cancer, sunscreens have been widely used by beachgoers in recent decades. UV filters contained in sunscreens were recently identified as emerging pollutants in coastal waters since they accumulate in the marine environment with different adverse effects. In fact, direct and/or indirect exposure to these components was proven to be harmful and eventually toxic to many invertebrate and vertebrate marine species.
  • 705
  • 21 Aug 2021
Topic Review
Underwater Image Enhancement
The complex underwater environment and light scattering effect lead to severe degradation problems in underwater images, such as color distortion, noise interference, and loss of details. To address the color distortion, noise interference, and loss of detail problems in underwater images, researchers propose a triple-branch dense block-based generative adversarial network (TDGAN) for the quality enhancement of underwater images.
  • 192
  • 24 Nov 2023
Topic Review
Ulva (Enteromorpha) Polysaccharides and Oligosaccharides
The high-valued utilization of Ulva (previously known as Enteromorpha) bioresources has drawn increasing attention due to the periodic blooms of world-wide green tide. The polysaccharide is the main functional component of Ulva and exhibits various physiological activities. The Ulva oligosaccharide as the degradation product of polysaccharide not only possesses some obvious activities, but also possesses excellent solubility and bioavailability. Both Ulva polysaccharides and oligosaccharides hold promising potential in the food industry as new functional foods or food additives. Studies on Ulva polysaccharides and oligosaccharides are increasing and have been the focus of the marine bioresources field.
  • 2.2K
  • 19 Mar 2022
Topic Review
Thin Layers (Oceanography)
Thin layers are concentrated aggregations of phytoplankton and zooplankton in coastal and offshore waters that are vertically compressed to thicknesses ranging from several centimeters up to a few meters and are horizontally extensive, sometimes for kilometers. Generally, thin layers have three basic criteria: 1) they must be horizontally and temporally persistent; 2) they must not exceed a critical threshold of vertical thickness; and 3) they must exceed a critical threshold of maximum concentration. The precise values for critical thresholds of thin layers has been debated for a long time due to the vast diversity of plankton, instrumentation, and environmental conditions. Thin layers have distinct biological, chemical, optical, and acoustical signatures which are difficult to measure with traditional sampling techniques such as nets and bottles. However, there has been a surge in studies of thin layers within the past two decades due to major advances in technology and instrumentation. Phytoplankton are often measured by optical instruments that can detect fluorescence such as LIDAR, and zooplankton are often measured by acoustic instruments that can detect acoustic backscattering such as ABS. These extraordinary concentrations of plankton have important implications for many aspects of marine ecology (e.g., phytoplankton growth dynamics, zooplankton grazing, behaviour, environmental effects, harmful algal blooms), as well as for ocean optics and acoustics. Zooplankton thin layers are often found slightly under phytoplankton layers because many feed on them. Thin layers occur in a wide variety of ocean environments, including estuaries, coastal shelves, fjords, bays, and the open ocean, and they are often associated with some form of vertical structure in the water column, such as pycnoclines, and in zones of reduced flow.
  • 323
  • 09 Nov 2022
Topic Review
The Larva of the Ascidian Halocynthia roretzi
The swimming larva represents the dispersal phase of ascidians, marine invertebrates belonging to tunicates. Due to its adhesive papillae, the larva searches the substrate, adheres to it, and undergoes metamorphosis, thereby becoming a sessile filter feeding animal. The papillae of H. roretzi, previously described as simple and conform, exhibit dynamic changes during settlement. This opens up new considerations on papillae morphology and evolution and deserves to be further investigated.
  • 848
  • 31 Dec 2021
Topic Review
Symbiotic Bacillota (Firmicutes) of Marine Macroalgae
The shift from the terrestrial to the marine environment to discover natural products has given rise to novel bioactive compounds, some of which have been approved for human medicine. However, the ocean, which makes up nearly three-quarters of the Earth’s surface, contains macro- and microorganisms whose natural products are yet to be explored. Among these underexplored marine organisms are macroalgae and their symbiotic microbes, such as Bacillota, a phylum of mostly Gram-positive bacteria previously known as Firmicutes. Macroalgae-associated Bacillota often produce chemical compounds that protect them and their hosts from competitive and harmful rivals.
  • 160
  • 13 Nov 2023
Topic Review
Steelhead Trout
Steelhead Trout is a name given to the anadromous form of the coastal rainbow trout (Oncorhynchus. m. irideus) or redband trout (O. m. gairdneri). The steelhead are native to freshwater and ocean environments across North America, but have been introduced to every other continent except Antarctica. Steelhead use aquatic obstructions like vegetation, boulders, and fallen trees as protection. Steelhead migrate to spawn during the summer months and the winter months.
  • 482
  • 14 Oct 2022
Topic Review
Shrimp Farming in the Philippines
Aquaculture serves the employment and food security needs of most Asian coastal countries, such as Bangladesh, China, India, Indonesia, the Philippines, Thailand, and Vietnam, which are all aquaculture-reliant countries with large aquaculture sectors. Aquaculture is a major driver of socioeconomic development in poor rural and coastal communities, particularly in Asia, and it relieves the pressure on, and helps to maintain the sustainability of, wild-caught species from rivers, lakes, and oceans, as it provides for the shortfalls of capture fisheries.  This industry has become a major source of food protein and it is predicted that it will support the seafood production as a sustainable alternative to wild-caught fish.
  • 13.7K
  • 16 Mar 2022
Topic Review
Shellfish as Biosensors
The use of biological objects in monitoring the state of the environment and the changes caused by the impact of environmental pollution on marine and fresh waters is a promising tool due to a lower cost in comparison to traditional monitoring and the ability to receive immediate information about the ecosystem status. Since the mid-1980s, Russian specialists have developed online biomonitoring systems; as in the rest of world, there are two main approaches that are currently applied to study the physiological status of potential biosensor shellfish species and to monitor freshwater and marine systems: valvometry (registration of gaping activity in bivalve mollusks) and photoplethysmography (registration of cardiac activity in mollusks and crustaceans).
  • 276
  • 16 Feb 2023
Topic Review
Secondary Metabolites of Genus Acanthella
Marine sponges are multicellular and primitive animals that potentially represent a wealthy source of novel drugs. The genus Acanthella (family Axinellidae) is renowned to produce various metabolites with various structural characteristics and bioactivities, including nitrogen-containing terpenoids, alkaloids, and sterols. Different metabolites were separated and characterized from different species of this genus using various spectroscopic and chromatographic techniques. The isolated metabolites are categorized according to their chemical classes into sesquiterpenes, diterpenes, alkaloids, steroid compounds, and others. Additionally, their reported biosynthetic and synthetic studies are also highlighted whenever applicable.
  • 308
  • 28 Apr 2023
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