Muscle trematode infection of alien cyprinids in the basin of the Middle Ob (Sibiria, Russia)

The book represents proceedings of Sixth International Symposium “Invasion of Alien Species in Holarctic. Borok -VI” (11 Oct. – 15 Oct. 2021, Borok – Uglich, Russia). The wide spectrum of problems related to appearance and spread of invasive plants and animals is discussed. The book may be interested for specialists in many fields, such as limnologists, hydrobiologists, ecologists, botanists, zoologists, geographers, managers of dealing with nature preservation and fisheries

Observations on Superfluid Meniscus in Rotating 3He-B

The parabolic superfluid meniscus has been seen for states in which only (1) the normal or (2) the superfluid component of 3He-B rotates. A reduced, temperature-dependent meniscus (1) was formed at small speeds Ω≲0.21 rad /s. A deeper-than-expected meniscus (2) was observed after a rapid halt of the cryostat, when the normal fluid stops during a short relaxation time, followed by slow decay of the superfluid circulation. The depth of the meniscus (2) was explained by a reactive radial force between the rotating superfluid and the stationary normal liquid.Peer reviewe

The role of non-commercial cyprinids in maintenance and spread of the opisthorchiasis focus in the middle Ob River basin (Tomsk region, Russia)

The study assessed the role of non-commercial cyprinid species in maintaining the opisthorchiasis focus in the middle Ob River basin, Tomsk region, Russia. The source of O. felineus infection for humans and carnivores is fish of the family Cyprinidae. This is the most numerous family, 14 species live in the middle Ob River basin, which includes 6 commercial species and 8 non-commercial species. This study aimed to investigate the current situation on infestation of non-commercial cyprinids with O. felineus metacercariae and their role in maintaining and spreading the natural focus of opisthorchiasis in the middle Ob River basin. We investigated 4 non-commercial species (tench, sunbleak, common bleak, gudgeon), which are highly abundant in water bodies. Tench, common bleak and gudgeon are objects of amateur fishing. These species are traditionally included in the diet of the local population. Opisthorchis felineus metacercariae were recorded in muscles of all the examined fish species. The identification of metacercariae was confirmed by morphological methods and PCR diagnostics. Tench and sunbleak are the main sources of opisthorchiasis infection in the floodplain lakes of the Ob River basin (the prevalence of tench infection is 89.3% and mean intensity of infection is 11.2 metacercariae per fish, the prevalence of sunbleak infection is 50.9% and the intensity of infection is 4.25 metacercariae per fish). The prevalence of infection in the introduced common bleak from the rivers of the middle Ob River basin is rapidly increasing from 2.4 (2016-2018) to 37.5% (2020-2021), and mean intensity of infection increased from 1 to 4.15. The epizootic state of water bodies in the middle Ob River basin remains unfavorable in relation to opisthorchiasis. Tench, common bleak and sunbleak, along with ide and dace, are the main source of infection for humans and animals, which is evidenced by high infection with Opisthorchis felineus metacercariae in these numerous fish species. They pose the greatest danger of infection of people and animals with opisthorchiasis. These species should be included in the campaign to avoid raw and poorly cooked fish in the diet. In addition, such species as roach, bream and sunbleak also pose the danger of infection with opisthorchiasis, but to a lesser extent

Evidence of 4He Crystallization via Quantum Tunneling at mK Temperatures

We have investigated creation of 4He crystals from the superfluid phase at the temperature range 2 mK–1.0 K. Statistical nucleation-event distributions in overpressure were found to be broad, asymmetric, and temperature independent below 100 mK. Our statistical analysis agrees with a theoretical model suggesting that solid formation is driven by macroscopical quantum-mechanical fluctuations from a seed preexisting in a cavity on the wall.Peer reviewe

Magnetic Nanoparticles in the Interstellar Medium: Emission Spectrum and Polarization

The presence of ferromagnetic or ferrimagnetic nanoparticles in the interstellar medium would give rise to magnetic dipole radiation at microwave and submm frequencies. Such grains may account for the strong mm-wavelength emission observed from a number of low-metallicity galaxies, including the Small Magellanic Cloud. We show how to calculate the absorption and scattering cross sections for such grains, with particular attention to metallic Fe, magnetite Fe3O4, and maghemite gamma-Fe2O3, all potentially present in the interstellar medium. The rate of Davis-Greenstein alignment by magnetic dissipation is also estimated. We determine the temperature of free-flying magnetic grains heated by starlight and we calculate the polarization of the magnetic dipole emission from both free-fliers and inclusions. For inclusions, the magnetic dipole emission is expected to be polarized orthogonally relative to the normal electric dipole radiation. Finally, we present self-consistent dielectric functions for metallic Fe, magnetite Fe3O4, and maghemite gamma-Fe2O3, enabling calculation of absorption and scattering cross sections from microwave to X-ray wavelengths.Comment: submitted to Ap.J. Fig. 10 has been corrected. Minor changes to the discussion in section 10.2.

The results of treatment of chronic recurrent aphthous stomatitis by gel containing zero-valent silver

The article presents the results of complex treatment of chronic recurrent aphthous stomatitis by methylcellulose-based gel with arabinogalactan biocomposite containing zero-valent silver in nano-valent condition. The gel was applied 3-6 times a day at the prescription of Diquertin 0,06 g 3 times a day and Fibrolar 0,3g 3 times a day. The proposed method of treatment allows to improve the effectiveness of treatment by increasing remission and reducing treatment terms

Разработка методики количественного анализа целевого и побочных продуктов синтеза 1,3-бис(3,4-дицианофенокси)бензола методом ВЭЖХ

Objectives. Determination of target products and byproducts is necessary for the quality control of phthalonitrile monomer synthesis as well as production scaling and performing related kinetic studies. High-performance liquid chromatography (HPLC) is a simple and affordable method for quantitative chemical analysis, which also verifies the quality of raw materials. The objective of this study was to develop an HPLC technique for determining the composition of the reaction mixture in the synthesis of 1,3-bis(3,4-dicyanophenoxy)benzene (DPB).Methods. Reversed-phase HPLC was used to quantitatively analyze the reaction mixture.Results. A simple and rapid method for the quantitative HPLC analysis of phthalonitrile monomers and their mixtures with reagents was developed. Reaction times and the accumulation of byproducts were also studied.Conclusions. The successful performance of the developed technique allows us to recommend it for practical applications. The results obtained for reactors of different sizes have good convergence, and DPB synthesis was successfully scaled up to intermediate scale equipment.Цели. Для аналитического контроля производства фталонитрильных мономеров, изучения масштабирования технологии их получения и проведения кинетических исследований актуальна задача по разработке способа определения концентрации целевого и побочных продуктов в присутствии реагентов. Наиболее простым и доступным методом количественного анализа рассматриваемых соединений является высокоэффективная жидкостная хроматография (ВЭЖХ), позволяющая также проводить верификацию сырья и контроль качества готовой продукции. Цель данной работы заключалась в разработке методики количественного анализа компонентов реакционной смеси при синтезе 1,3-бис(3,4-дицианофенокси)бензола (ДБФ) методом ВЭЖХ.Методы. Для количественного анализа компонентов реакционной смеси использовали метод ВЭЖХ в обращенно-фазовом режиме.Результаты. Разработана простая и быстрая методика количественного анализа фталонитрильных мономеров и их смесей с реагентами методом ВЭЖХ. По данным исследования конверсии компонентов реакционной смеси сделан вывод о продолжительности реакции и накоплении побочных продуктов.Выводы. Успешная апробация позволяет рекомендовать разработанную методику для применения в аналитической практике. Результаты, полученные при переходе от реакции в колбе к реактору объемом 15 л, характеризуются хорошей сходимостью. Синтез ДФБ успешно масштабируется на оборудование промежуточного масштаба

Observation of Dispersion in the J=2+ Collective Modes of He-3-B by Nonlinear Acoustic Spectroscopy

Parametric excitation yields new results, which cannot be obtained by conventional linear spectroscopy, on the collective modes in superfluid He-3-B. In our ultrasonic experiments, performed in a chamber with four quartz crystals, we have excited the real squashing (J = 2+) modes by two simultaneous sound waves which are mutually either parallel, orthogonal, or antiparallel. Qualitatively these results are in agreement with the theoretical dispersion relation of the J = 2+ modes, and quantitatively we have been able to extract the collective-mode velocities from the line splittings in zero magnetic field

Magnetic phenomena in co-containing layered double hydroxides

Magnetic behavior of CoII(n)AlIII layered double hydroxides (LDHs) (n=Co/Al=2 and 3) intercalated with nitrate was studied as a function of temperature. Both LDH compounds are paramagnetic above about 8K. A rapid increase of their magnetic moments occurs below this temperature until the moments reach the maximum values at Tmax of 4.0K and 3.2K for Co(2)Al-NO3 and Co(3)Al-NO3, respectively. Below Tmax, the zero-field-cooled and the field-cooled static magnetization curves are strongly different. Along with this low-temperature phenomena, Co(2)Al-NO3 and Co(3)Al-NO3 demonstrate anomalous behavior of their temperature dependence magnetic susceptibility in a highertemperature range: between 75 and 175K, both the paramagnetic Curie temperature and the effective magnetic moment change in a non-monotonous way. Possible structural reasons of the observed magnetic behavior of the CoII(n)AlIII LDHs are discussed.publishe

In vitro degradation behavior and cytocompatibility of Mg–Zn–Zr alloys

Zinc and zirconium were selected as the alloying elements in biodegradable magnesium alloys, considering their strengthening effect and good biocompatibility. The degradation rate, hydrogen evolution, ion release, surface layer and in vitro cytotoxicity of two Mg–Zn–Zr alloys, i.e. ZK30 and ZK60, and a WE-type alloy (Mg–Y–RE–Zr) were investigated by means of long-term static immersion testing in Hank’s solution, non-static immersion testing in Hank’s solution and cell-material interaction analysis. It was found that, among these three magnesium alloys, ZK30 had the lowest degradation rate and the least hydrogen evolution. A magnesium calcium phosphate layer was formed on the surface of ZK30 sample during non-static immersion and its degradation caused minute changes in the ion concentrations and pH value of Hank’s solution. In addition, the ZK30 alloy showed insignificant cytotoxicity against bone marrow stromal cells as compared with biocompatible hydroxyapatite (HA) and the WE-type alloy. After prolonged incubation for 7 days, a stimulatory effect on cell proliferation was observed. The results of the present study suggested that ZK30 could be a promising material for biodegradable orthopedic implants and worth further investigation to evaluate its in vitro and in vivo degradation behavior