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For the first time for the Black Sea region in recreation zones (RZ) a comprehensive monitoring of microplastics pollution (MP) was carried out, including a study of the spatial and temporal distribution of microplastic (MPs) qualitative and quantitative parameters in beach and bottom sediments, as well as in the surface water layer of adjacent water areas. Monitoring was carried out in the period 2018-2021 quarterly in calm weather and after storm episodes in five popular RZ of the Sevastopol region and two control areas (CA). A trend of MPs cumulation in beach and bottom sediments, as well as in the surface water layer of all studied areas was established. During the monitoring period, the MP concentration in beach sediments increased by 1,5 – 5 times, in bottom sediments by 5,5 – 6 times. The MP concentration in the surface water layer of the aquatories increased by 1,5 – 9,7 times. The maximum MP average concentrations in beach sediments was 77-100 units·m-2. At average MP concentrations in beach, bottom sediments and in the surface water layer of adjacent aquatories, which are 27 units·m-2, 11,5 units·kg-1 (dry weight) and 0,66 units·m-3, respectively. According to the morphotype, MPs particles were differentiated into five main groups: fragments, granules, pellets, films, fibers. In the beach sediments fragments accounted for the largest share – 48-80%, fibers reached 25,8%; films were found on all beaches 1-21%. In all samples of bottom sediments, the proportion of fragments was maximum 50-83%, fibers 1-33%. Granules and pellets accounted for no more than 10%. Acknowledgment. The study was carried out with the financial support of the Russian Foundation for Basic Research within the framework of the scientific project 18-44-920014 rₐ, as well as within the framework of research work no. registration: 121040600178-6 and 121041400077-1. Also see: https://micro2022.sciencesconf.org/426418/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

Quartzite is a mountain igneous sedimentary rock formed by fusion of quartz sand with other minerals. The volume of its consumption is increases constantly. For this reason resolution of the problem of the feasibility of developing a new formation or a new site (lode) of an existing quartzite deposit depends directly on its properties. This is especially true for the use of quartzite in the metal industry where it is exposed to high temperature. As a rule studying properties of quartzite for water absorption, open porosity and apparent density is performed at room temperature. Macro and microstructures are studied before and after calcining at 1450°C using optical microscopes that make it possible to conduct X-ray phase analysis.

Data on comparative efficacy of various available endoscopic ultrasound-guided liver biopsy (EUS-LB) needles are limited. We sought to compare the performance of a novel Franseen-tip 22G fine-needle biopsy (FNB) device to that of 19G needle platforms for liver parenchyma. Consecutive patients referred for EUS and suspected to have hepatic parenchymal disease underwent EUS-LB using different EUS needles and were included in this retrospective study. Two blinded expert liver pathologists independently reviewed and reported on: total number of tissue fragments, length of longest fragment, number of complete and incomplete portal tracts (CPT and IPT), and specimen adequacy. A 22G Franseen-tip needle (A) was used in 30 patients; 19G Tru-Cut needle (B) in 50 patients; 19G reverse beveled non-Tru-Cut needle (C) in 27 patients; and a 19G flexible non-Tru-Cut needle (D) in 28 patients. In the order of needles, A, B, C and D, > 10 tissue fragments were obtained in 100%, 6%, 82%, and 96% samples, the mean number of CPTs was 6.9; 3.0; 7.3; and 16.9, length of longest fragment was 3.8, 4. 7, 3.9, and 8.4 mm, and specimen adequacy was 66.7%, 46%, 82.1%, and 81.5%, respectively. A positive correlation was obtained between number of CPTs and length of longest fragment in samples accrued by 19G needles. EUS-LB specimens using 22G Franseen-tip needle appear highly fragmented, leading to inferior specimen adequacy compared to 19G non-Tru-Cut needles. We also report on using length of longest fragment as an additional criterion for specimen adequacy as it positively correlates with number of CPTs standard.

Following successful proof-of-concept experiments, we constructed compact varying-gap undulator with Hydraulic-Assist Driver. The 1 . 5 m long undulator features a pure permanent magnet structure, period of 28 . 4 m m and a minimum gap of 6 . 75 m m . The bench test of the device indicated excellent mechanical and magnetic performances. It demonstrated ≤ 3 ° R M S optical phase errors in a wide range of gap variation; ∼ 1 . 0 × 1 0 − 4 (or better) repeatability in normalized K u n d ( Δ K ∕ K ) from one gap variation to another. In special mode, when the gap was varied in correlation with undulator temperature, undulator demonstrated ∼ 6 . 6 × 1 0 − 5 R M S of Δ K ∕ K long-term ( ∼ 24hrs) stability while the undulator temperature change was ∼ 1 . 3 ° C. In this paper, we discuss the critical design components and criteria required for undulator mechanical stability and magnetic performance. We also describe our Lab-View-based control system governing the Hydraulic-Assist Driver. Finally, we present the test setup and results.

Two different views on factors limiting the abundance of pacific salmons in the marine period of their life are compared. According to traditional point of view, food resources are limited in the marine and oceanic epipelagic biotopes, so a strong competition for food exists between different species of genus Oncorhynchus or between pink salmon O. gorbuscha and other species that makes theIr abundance lower and biological conditions worse. Negative anomaly of the sea surface temperature is considered traditionally as a factor controlling the salmons distribution in the ocean because of the food supply worsening. The other point of view is proposed by authors in the 1980s and is based on comprehensive ecosystem studies of the Far Eastern Seas and the North Pacific. Following to this view, the food resources do not limit the abundance of salmons, which play secondary roles in trophic networks within the subarctic epipelagic layer. Besides, these data do not confirm stenotherm habits of salmons, particularly in conditions of low temperature (salmons could be found in the northern Bering and Okhotsk Seas even in winter). In favor of the latter view, new data are presented for 2018, when the highest biomass of the Russian salmons was observed, primarily due to pink salmon abundance, and the absolutely record Russian catch of pacific salmons in 677,200 t was landed.