Oxidative Stress in Mussel Induced by Different-Sized Plastics.

Polyethylene and polystyrene are massively used around the world in various applications and are the most abundant plastic waste. Once in the marine environment, under the influence of physical and chemical factors, plastic products degrade, changing from the size category of macroplastics to microplastics. In order to study the effect of plastic on marine organisms, we modeled the conditions of environmental pollution with different-sized plastic-polystyrene microparticles of 0.

The solution of sound propagation modeling problems for environment impact assessment by the mode parabolic equations methoda).

The method of sound propagation modeling based on the mode parabolic equations (MPEs) theory is applied to the verification scenarios for environmental impact assessment. The results for selected scenarios from the 2022 Cambridge Joint Industry Programme Acoustic Modelling Workshop and the configuration of the computational programs AMPLE and MPE for these scenarios is discussed. Furthermore, it is revealed how the results for these scenarios change in the case of the bottom slope across and along the propagation path.

Application of concentration-weighted trajectory approach to identify sources with high anthropogenic mercury emissions in the East Asia.

The study evaluates the applicability of the CWT method for identifying mercury sources in a region with high anthropogenic emissions. Analysis is conducted to compare results on grids of 1 × 1°, 0.5 × 0.

Mercury and stable nitrogen isotope ratios in the hair of bearded seals (Erignathus barbatus nauticus) from the Sea of Okhotsk.

The mercury pollution status in the northwestern Sea of Okhotsk remains largely unexplored. In this study, hair samples were collected from 40 bearded seals harvested between August and October 2021 in the region. Total mercury (THg) concentrations in the samples exhibited a wide range from 137 to 1885 ng/g (median: 407 ng/g).

Twenty-Meter Laser Strainmeter "Popova Isl.".

This paper describes the design and principle of operation of a 20 m laser strainmeter of unequal-arm type created on the basis of a Michelson interferometer and frequency-stabilized helium-neon laser. The interferometry methods used allow the measurement of the displacement of an Earth's crust section on the base of the laser strainmeter with an accuracy of 30 pm in the frequency range from 0 (conventionally) to 1000 Hz. This laser strainmeter, when connected to an accurate time system providing an accuracy of 1 μs, should structurally become a part of the laser interferometric seismoacoustic observatory, consisting of spatially separated laser strainmeters installed in various regions of Russia.

Comment on: "Anomalous reflection from a two-layered marine sediment" [J. Acoust. Soc. Am. 155, 1285-1296 (2024)] (L).

Buckingham [(2024). J. Acoust.

Photoaging Elevated the Genotoxicity of Polystyrene Microplastics to Marine Mussel (Gould, 1850).

Micro-sized particles of synthetic polymers (microplastics) are found in all parts of marine ecosystems. This fact requires intensive study of the degree of danger of such particles to the life activity of hydrobionts and needs additional research. It is evident that hydrobionts in the marine environment are exposed to microplastics modified by biotic and abiotic degradation.

Three-dimensional modelling of underwater noise produced by a bulk carrier vessel and estimation of its environmental impacta).

This study presents the results of three-dimensional (3D) propagation modeling of noise from a transiting bulk carrier vessel. In the simulated scenario, the surface vessel is moving past a bottom-mounted hydrophone system. Sound levels are estimated in decidecade frequency bands as the vessel transits past the hydrophone, and the simulation results are compared against real measured data.

Hard- and Software Controlled Complex for Gas-Strain Monitoring of Transition Zones.

The article describes a hard- and software controlled complex for gas-strain monitoring, consisting of stationary laser strainmeters and a laser nanobarograph, a stationary gas analyzer, and a weather station installed at Shultz Cape in the Sea of Japan; and a mobile shipboard complex, consisting of a gas analyzer and a weather station installed in a scientific research vessel. In the course of trial methodological measurements on these systems, general patterns were identified in the dynamics of greenhouse gases and deformation of the Earth's crust in the range of diurnal and semi-diurnal tides, and also in the range of ultra-low frequencies, caused by atmospheric wave processes and, possibly, individual tones of the Earth's eigen oscillations.

Ice sheet and precession controlled subarctic Pacific productivity and upwelling over the last 550,000 years.

The polar oceans play a vital role in regulating atmospheric CO concentrations (pCO) during the Pleistocene glacial cycles. However, despite being the largest modern reservoir of respired carbon, the impact of the subarctic Pacific remains poorly understood due to limited records. Here, we present high-resolution, Th-normalized export productivity records from the subarctic northwestern Pacific covering the last five glacial cycles.

REVIEW: Evidence supporting the 'preparation for oxidative stress' (POS) strategy in animals in their natural environment.

Hypometabolism is a common strategy employed by resilient species to withstand environmental stressors that would be life-threatening for other organisms. Under conditions such as hypoxia/anoxia, temperature and salinity stress, or seasonal changes (e.g.

Biodegradation of polyethylene in digestive gland homogenates of marine invertebrates.

Вiotic factors may be the driving force of plastic fragmentation along with abiotic factors. Since understanding the processes of biodegradation and biological depolymerization of plastic is important, a new methodological approach was proposed in this study to investigate the role of marine invertebrate digestive enzymes in plastic biodegradation. The aim of this study is to evaluate the possibility of enzymatic biodegradation of polyethylene fragments in the digestive gland homogenate of marine invertebrates differing in their feeding type ().

Radioactivity of anthropogenic and natural radionuclides in marine sediments of the Chaun Bay, East Siberian Sea.

Natural radioactive isotopes serve as a useful proxy of geological and geochemical processes in marine environment, while radiocesium serves as an indicator of man-made contamination. Monitoring of natural and anthropogenic radioactivity under conditions of the climate changes in the Arctic region is of high importance in investigations of this natural system. For the first time, we report the data on spatial distribution of natural (Th, Ra, K) and anthropogenic (Cs) radionuclide activities in the marine sediments from Chaun Bay (East Siberian Sea).

Transport of the Tumen River water to the Far Eastern Marine Reserve (Posyet Bay) based on in situ, satellite data and Lagrangian modeling using ROMS current velocity output.

We study physical mechanisms of the Tumen River water transport in the area of the Posyet Bay (Peter the Great Bay, Sea of Japan). This study is based on the satellite and in situ measurements, and numerical simulation of advection of river water by the current velocity simulated by Regional Ocean Model System (ROMS). The importance of this study is in identification of the reasons of the transport of pollutants into the area of the Far Eastern Marine Reserve.

Verification of Data from Supersensitive Detector of Hydrosphere Pressure Variations.

The paper describes experimental research and the results of these studies carried out in various bays of the Primorsky Territory of Russia using a supersensitive detector of hydrosphere pressure variations and a sound velocity profiler with pressure and temperature sensors. In all experiments, instruments, rigidly fixed to each other, were placed on the bottom at a depth of up to 10 m. Comparison of in-situ data from these instruments allowed us to experimentally calculate the coefficient of data conversion of the supersensitive detector of hydrosphere pressure variations when registering sea waves with periods ranging from several seconds to tens of minutes.

The Relationship between Lifespan of Marine Bivalves and Their Fatty Acids of Mitochondria Lipids.

Marine bivalves belonging to the and Families were used in this research. The specific objectives of this study were: to determine the Fatty Acids (FAs) of mitochondrial gill membranes in bivalves with different lifespans, belonging to the same family, and to calculate their peroxidation index; to compare the levels of ROS generation, malondialdehyde (MDA), and protein carbonyls in the mitochondria of gills, in vitro, during the initiation of free-radical oxation; to investigate whether the FAs of mitochondria gill membranes affect the degree of their oxidative damage and the maximum lifespan of species (MLS). The qualitative membrane lipid composition was uniform in the studied marine bivalves, regardless of their MLS.

Assessment of contamination of marine sediments and their potential toxicity in the Uglovoy Bay, Peter the Great Gulf, Sea of Japan/East Sea.

The content of harmful heavy metals in the bottom sediments of the Uglovoy Bay (Peter the Great Gulf, Sea of Japan/East Sea) was studied based on the surveys carried out in 2016-2021. The contamination of the sediments in the bay was compared to the background concentrations of elements and to common contamination indices. The degree of contamination was calculated using the contamination factor (C), modified overall degree of contamination (mC), and index of geoaccumulation (I).

Dietary Exposure to Particles of Polytetrafluoroethylene (PTFE) and Polymethylmethacrylate (PMMA) Induces Different Responses in Periwinkles .

The marine and ocean water pollution with different-sized plastic waste poses a real threat to the lives of the next generations. Plastic, including microplastics, is found in all types of water bodies and in the organisms that live in them. However, given the chemical diversity of plastic particles, data on their toxicity are currently incomplete.

First Satellite Tagging of the Northern Fur Seals () on the Tyuleniy Island, the Sea of Okhotsk.

In October 2018, three Northern fur seals (two adult females and one juvenile male) were deployed with satellite tags on the Tyuleniy Island in the Sea of Okhotsk. The operational time of the tags ranged from 33 to 203 days. The adult females started their winter migration in the first half of November; the initial stage of their winter migration occurred in the Japan/East Sea, which they entered through the La Perouse Strait.

A Complex of Marine Geophysical Methods for Studying Gas Emission Process on the Arctic Shelf.

The Russian sector of the arctic shelf is the longest in the world. Quite a lot of places of massive discharge of bubble methane from the seabed into the water column and further into the atmosphere were found there. This natural phenomenon requires an extensive complex of geological, biological, geophysical, and chemical studies.

The origin of loud claps during endovenous laser treatments.

Optoacoustic and ultrasound methods have shown that the loud "claps" perceived by patients and medical staff during endovenous laser ablation (EVLA) are caused by volumetric blood boiling when large vapor-gas bubbles appear and collapse under the action of laser radiation, which is well absorbed in water. Acoustic effects when using lasers in the near infrared range (1.94, 1.

Geochemistry aspects of modern mercury accumulation in bottom sediments from the south-western Chukchi Sea.

Mercury (Hg) having a high migration capacity reach the Arctic region via the atmosphere. The absorbers for Hg are sea bottom sediments. Sedimentation in the Chukchi Sea occurs under the influence of highly productive Pacific waters entering through the Bering Strait and the inflow of a terrigenous component from the western direction with the Siberian Coastal Current.

Mercury content in the fur of sea otters (Enhydra lutris) from the Commander Islands.

The sea otter (Enhydra lutris) is a keystone species in the ecosystem which is currently in depression in Russia. The objectives of this study were to: (1) establish if the sea otters from the Commander Islands have hazardous levels of mercury (Hg) in their fur; (2) assess Hg pollution in sea otters during a period of high abundance and population depression; (3) identify the age and sex differences in sea otters by Hg content. The sea otters were classified from no to low risk for Hg health effects.

Genotoxic Effects of Exposure to Water-Soluble Fraction of Diesel Fuel in Sand Dollar Gametes.

Pollution of marine areas with oil and oil products is steadily growing. As part of this connection, the study of the impact of petroleum hydrocarbons on marine hydrobionts is an urgent issue of modern ecotoxicology. In our study, the genotoxic effect of the water-soluble fraction of diesel fuel at different concentrations on the gametes of the sand dollar was evaluated.