bluuebunny/crossref_metadata_2025 huggingface dataset:
Absolute Stability of Neutral Systems with Lurie Type Nonlinearity
Authors: Diblík Josef , Khusainov Denys Ya , Shatyrko Andriy , Baštinec Jaromír , Svoboda Zdeněk
Published: January 2022

The paper studies absolute stability of neutral differential nonlinear systems

x˙(t)=Axt+Bxt−τ+Dx˙t−τ+bf(σ(t)),σ(t)=cTx(t),t⩾0$$ \begin{align}\dot x(t)=Ax\left ( t \right )+Bx\left ( {t-\tau} \right ) +D\dot x\left ( {t-\tau} \right ) +bf({\sigma (t)}),\,\, \sigma (t)=c^Tx(t), \,\, t\geqslant 0 \end{align} $$

wherexis an unknown vector,A,BandDare constant matrices,bandcare column constant vectors, 𝜏 > 0 is a constant delay andfis a Lurie-type nonlinear function satisfying Lipschitz condition. Absolute stability is analyzed by a general Lyapunov-Krasovskii functional with the results compared with those previously known.
A revised model for the effect of nanoparticle mass flux on the thermal instability of a nanofluid layer
Authors: Alharbi Ozwah S. , Abdullah Abdullah A.
Published: January 2022

A revised model of the nanoparticle mass flux is introduced and used to study the thermal instability of the Rayleigh-Benard problem for a horizontal layer of nanofluid heated from below. The motion of nanoparticles is characterized by the effects of thermophoresis and Brownian diffusion. The nanofluid layer is confined between two rigid boundaries. Both boundaries are assumed to be impenetrable to nanoparticles with their distribution being determined from a conservation condition. The material properties of the nanofluid are allowed to depend on the local volume fraction of nanoparticles and are modelled by non-constant constitutive expressions developed by Kanafer and Vafai based on experimental data. The results show that the profile of the nanoparticle volume fraction is of exponential type in the steady-state solution. The resulting equations of the problem constitute an eigenvalue problem which is solved using the Chebyshev tau method. The critical values of the thermal Rayleigh number are calculated for several values of the parameters of the problem. Moreover, the critical eigenvalues obtained were real-valued, which indicates that the mode of instability is via a stationary mode.
Solution growth of chalcopyrite Cu(In1−x
Ga
x
)Se2 single crystals for high open-circuit voltage photovoltaic device
Authors: Nagaoka Akira , Shigeeda Yusuke , Nishioka Kensuke , Masuda Taizo , Yoshino Kenji
Published: January 2022

I–III–VI2 Chalcopyrite Cu(In1−x
Ga
x
)Se2 (CIGS) has attracted attention as absorbing layer in photovoltaic (PV) device. In this study, we investigated the fundamental properties of CIGS single crystals, and fabricated single crystal-based PV device. CIGS single crystals without secondary phase were successfully grown by In-solvent traveling heater method (THM). The conversion of conduction type from n- to p-type can be observed above 0.3 of Ga ratio x because of high acceptor defect concentration. PV device based on high-quality CIGS bulk single crystal demonstrates high open-circuit voltage of 0.765 V with the efficiency of 12.6%.
Stress concentration effect on deflection and stress fields of a master leaf spring through domain decomposition and geometry updation technique
Authors: Ghuku Sushanta , Saha Kashi Nath
Published: January 2022

Theoretical and experimental large deflection and stress analysis of a master leaf spring considering stress concentration effect of clamping is reported. The non-uniformly curved master leaf spring under three point bending subjected to moving boundaries is modeled. Geometrically nonlinear strain-displacement relations, as necessary for the theoretical analysis, are derived through visualization of physics behind the large deformation problem. An embedded curvilinear coordinate system is considered, to study the combined effects of non-uniform curvature, bending, stretching and shear deformation including cross-sectional warping. Governing equation of the non-uniformly curved beam system is derived in variational form using energy method, based on linear material constitutive relations and the derived nonlinear kinematic relations. An iterative solution scheme through successive geometry updation is developed and executed in MATLAB® software to solve the governing equation involving strong geometric nonlinearity together with complicating moving boundary effect. Experimental deflection profiles under static loading are obtained through manual image processing technique using AutoCAD® software. Whereas, strain measurements are performed using strain gauges with data acquisition system (HBM-MX840B). Comparison between the theoretical and experimental results lead towards observation on stress concentration effect due to presence of geometric discontinuity in form of a small hole in the physical system. A modified formulation is proposed using domain decomposition method incorporating effect of geometric discontinuity through an equivalent curved beam geometry of variable cross-section. The modified theoretical model is validated successfully with the experimental results, and observations on stress characteristics and effect of hole diameter to beam width ratio are made.
Preparation of efficient piezoelectric PVDF–HFP/Ni composite films by high electric field poling
Authors: Lei Dan , Hu Ning , Wu Liangke , Huang Rongyi , Lee Alamusi , Jin Zhaonan , Wang Yang
Published: January 2022

Poly(vinylidene fluoride) (PVDF) and its copolymers have been widely studied due to their excellent piezoelectricity and ferroelectricity. In this study, composite films are prepared by adding Ni nanoparticles (0.00–0.3 wt%) into poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF–HFP) matrix by solution casting, uniaxial stretching, and high electric field poling. It is found that when the maximum electric field E
max for poling is 130 MV m−1, the calibrated open circuit voltage of the pure PVDF–HFP films reaches 3.12 V, which is much higher than those poled by a lower electric field (70 MV m−1: 1.40 V; 90 MV m−1: 2.29 V). This result shows that the effect of poling on the generated output voltage is decisive. By adding 0.1 wt% Ni nanoparticles, it increases to 3.84 V, 23% higher than that of the pure PVDF–HFP films. To further understand the enhancement mechanism, the effects of Ni nanoparticles on initial crystallization, uniaxial stretching, and high electric field poling are investigated by X-ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy, and differential scanning calorimetry.
Optimization of nano coating to reduce the thermal deformation of ball screws
Authors: Gao Xiangsheng , Zhang Kuan , Wang Min , Zan Tao , Gao Peng , Liu Chaozong
Published: January 2022

To reduce the thermal deformation of ball screws, the process of nano coating preparation for coating on ball screws to reduce temperature rise and thereby thermal deformation was discussed in this article. Simultaneously, the cooling mechanism was presented. The thermal channels and the relatively even distribution of graphene in the nano coating were observed in scanning electron microscopic images. In terms of the preparation of nano coating, optimization design was carried out to obtain the optimized material ratio and nozzle flow through orthogonal experiment. The influence of design parameters of nano coating on reducing thermal deformation was also discussed. The experimental results show that the maximum temperature rise, thermal deformation, and time to reach thermal balance decreased by 12.5, 69.1, and 46.3%, respectively. The effectiveness of nano coating in reducing thermal deformation was validated experimentally.
Intensification of thermal stratification on dissipative chemically heating fluid with cross-diffusion and magnetic field over a wedge
Authors: Adnan  , Khan Umar , Ahmed Naveed , Mohyud-Din Syed Tauseef , Sherif El-Sayed M. , Khan Ilyas
Published: January 2022

This paper aims to examine the heat and mass characteristics for thermally stratified chemically heated, dissipative flow under the cross-diffusion and imposed Lorentz forces. A self-similar model is obtained employing suitable similarity transformations. Then, the RK technique is used for mathematical analysis. The stimulations of pertinent physical quantities in the flow regimes, shear stresses, and the Nusselt number were examined graphically. It is noted that more radiative flow favors the thermal behavior of the fluid and increases in the Prandtl number causes the decrease in thermal characteristics. Moreover, decreases in mass characteristics were examined by the fluctuating chemical reaction and Schmidt parameters. Lastly, key outcomes of the work are pinpointed.
What dominates heat transfer performance of a double-pipe heat exchanger
Authors: Zheng Dan , Hu Zhenwei , Tian Liting , Wang Jin , Sundén Bengt
Published: January 2022

ZnO–water nanofluid in an inner pipe was experimentally investigated to improve the thermal efficiency of double-pipe heat exchangers. In this work, a 57.6% increase in the Nusselt number was obtained at Re = 14,340 when the ZnO–water nanofluid flowed through a helically corrugated tube. It was found that helical corrugation played a more important role in heat transfer enhancement than thermophysical properties of the nanofluid at the Reynolds number below 10,221. In addition, with the increase of the Reynolds number, the advantages of nanofluids in thermal performance become obvious, and Nusselt numbers increase by 28.5 and 30.6% with the effects of helical corrugation and ZnO–nanofluid, respectively, at Re = 14,349.
Time-periodic pulse electroosmotic flow of Jeffreys fluids through a microannulus
Authors: Li Dongsheng , Ma Liang , Dong Jiayin , Li Kun
Published: January 2022

In this article, we investigate the time-periodic pulse electroosmotic flow (EOF) of Jeffreys fluids through a microannulus. By using the Laplace transform method, the velocity expression of the pulse EOF is derived. The effect of some variables on the time it takes for the fluid to go from a static state to a flowing state is analyzed. We find that increasing the relaxation time

λ
¯

1

{\bar{\lambda }}_{\text{1}}

and decreasing the inner and outer radius ratio

α

\alpha

will result in longer time for the fluid to reach the flowing state, but the retardation time

λ
¯

2

{\bar{\lambda }}_{\text{2}}

and the inner and outer zeta potential ratio

β

\beta

have little effect on it. The impact of some related parameters on the pulse EOF velocity for different inner and outer radius ratios (

α

\alpha

) is discussed in detail. The results show that for a smaller inner and outer radius ratio

α

\alpha

, the velocity amplitude increases with the relaxation time

λ
¯

1

{\bar{\lambda }}_{\text{1}}

and decreases with the retardation time

λ
¯

2

{\bar{\lambda }}_{\text{2}}

. As the inner and outer radius ratio

α

\alpha

increases, the effect of relaxation time

λ
¯

1

{\bar{\lambda }}_{\text{1}}

on velocity amplitude gradually weakens or even becomes insignificant, and the effect of the retardation time

λ
¯

2

{\bar{\lambda }}_{\text{2}}

on the velocity amplitude remains unchanged. Moreover, the velocity amplitude will decrease with the increase in the inner and outer radius ratio

α

\alpha

and its change range will expand from the electric double layer near the annular wall to the entire flow region.
Professionalisierungsdynamiken in der Palliativpflege
Authors: Scheid Claudia , Ummel Hannes
Published: January 2022

Der vorliegenden Artikel widmet sich der Frage, mit welchen Begriffen – etwa Beruf, Beratung, Expertentätigkeit, Profession – sich palliative Pflege adäquat erfassen lässt. Ein Ausgangspunkt ist der im Feld geäußerte Anspruch, diese sei als Profession zu verstehen. Eine theoretische Modellierung zeigt, dass Palliativpflege als ein professionalisierungsbedürftiges Handlungsfeld verstanden werden kann. Mithilfe von Fallerzählungen zweier qualifizierter Pflegender aus diesem Bereich wird sondiert, ob bestehende Handlungsorientierungen dem theoretischen Entwurf entsprechen. Dabei zeigen sich Professionalisierungsdynamiken, aber ebenso deutlich Tendenzen einer „(Noch-)Nicht-Professionalisierung“. Für Ersteres steht insbesondere die „Fallperspektive“, also jene basale „Selektivität der Wahrnehmung“, mit der die in einer Lebenspraxis bestehende spezifische Krise überhaupt erkannt und dargestellt werden kann (Maiwald, Bergmann). Für Letztere stehen zum Beispiel eine Expertenorientierung, welche die Hilfsbedürftigkeit der Klientinnen und Klienten letztlich an diese zurückdelegiert, oder auch Formen kompensatorischer Entgrenzung in ungefilterte Diffusität. Neben der begrifflichen Diskussion entsteht ein Bild von Chancen, Grenzen und Belastungen „semi-professionell“ ausgeführter Tätigkeiten für alle Beteiligten.
Fünf Thesenpapiere von Falk Wagner
Authors: Murrmann-Kahl Michael
Published: January 2022

Falk Wagner (1939–1998) was the leading Hegelian in late 20th century German Protestant theology. Wagner who had studied philosophy with Theodor W. Adorno and Wolfgang Cramer in Frankfurt am Main and Systematic Theology with Wolfhart Pannenberg at the University of Mainz taught Systematic Theology at the Universities of Munich and, since 1988, Vienna. He published several influential books. In his lectures and seminars he frequently handed out short theory papers to his students which should serve as the basis for debate. The five texts presented here for the first time deal with the problems of individual in society and of the modern history of theology, with the doctrine of God (creator and trinity), with the significance of the Bible for the systematic theology and finally with the concept of „Subjektivität“ in G. W. F. Hegel’s philosophy. These texts are an essential source for the development of Wagner’s thought when teaching at the university of Munich until 1988.
The United Kingdom after brexit
Authors: Ananieva Elena , Babynina Lyudmila , Entin Mark , Galushko Dmitriy , Godovanyuk Kira , Kuznetsov Alexey , McHutchon David , Ostapenko Galina , Okhoshin Oleg , Podkolzina Inna , Polyakova Elena , Sillars Jim , Susloparova Elena , Shein Sergey , Shkrobtak Igor
Published: January 2022

The edited book by Russian scholars and UK experts focuses on the political and economic developments Britain faces following the end of the post-Brexit transition period. Against the backdrop of the coronavirus pandemic, B. Johnson’s Conservative government was confronted with many challenges, from trying to put together an adequate anti-crisis domestic policy to fitting UK foreign policy into the «Global Britain» framework. The authors look into the UK foreign trade policy, the roadblocks in the implementation of the UK – EU Trade and Cooperation Agreement, the impact of Brexit and the pandemic on the competitiveness of London as a leading financial hub, and how UK plans moving over to a climate-neutral economy. Special emphasis is given to the centrifugal trends in Scotland and Northern Ireland that conspicuously manifested themselves upon the UK withdrawal from the EU, along with the phenomenon of anti-monarchism. The authors explore Russia – UK relations in the light of the Integrated Review and provide an analysis of the latest developments in the UK defense strategy and armed forces.
The Intervention of the Social Service in the Multidisciplinary Teams to Combat COVID-19. The Case of the Municipality of Amadora (Portugal)
Authors:   Universidade Lusófona, Ramalho Nelsón , Moreno Ana ,   Câmara Municipal da Amadora, Neves Sandra ,   Instituto de Segurança Social I. P.
Published: January 2022

The creation of Multidisciplinary Teams to monitor patients with COVID-19 and those infected with SARS-CoV-2 in a situation of home confinement was one of the measures established by the Portuguese government to help stop the spreading of the infection in the parishes of the Lisbon Metropolitan Area more affected by the pandemic. To know its way of functioning and acting, as well as the role of social workers in the context of crisis and public health emergency, a qualitative study was developed based on interviews by focus groups and document analysis. It was found that the Multidisciplinary Teams and the intervention model carried out were fundamental in helping to break the transmission chains and prevent the growth of new contamination, with social workers having a crucial role in supporting the most vulnerable households in a containment situation.
Secondary victimization of sexual violence. Analysis of secondary victimization in cases of sexual violence and sexting
Authors:   Universidad de Granada, Córdoba Cristina R.
Published: January 2022

At present, secondary victimization of sexual violence is very common and it has negative effects to the victims. Secondary victimization raises the issues of the victims and it originates others. This victimization often associates with justice system but it may create by society, victims’ close environment and mass and social media. The primary objective of that research is to establish secondary victimization’s characteristics in the last years and its linkage with genre stereotypes about victims’ behavior before, during and after sexual violence. These stereotypes are the same in the different countries. In the current study, they assessed 10 cases using news, declarations, videos and sentences.
Public policies against gender violence and the problems for their implementation: Guayaquil-Ecuador analysis case
Authors:   Universidad Católica Santiago de Guayaquil, Mendieta Lourdes
Published: January 2022

Gender violence is a global social problem. Although in Ecuador there have been achievements in recent decades, this phenomenon persists and tends to increase. This contrasts with the progressive approval of regulations aimed at ending this social problem and responding to the victims. It is relevant, therefore, to analyze the implementation of public policies, in the specific case of the city of Guayaquil, through the documentary review of the investigative, normative and strategic background, as a part of the objectives of a doctoral thesis that is on investigative process1. For this, the data that indicate the problem magnitude were interpreted and the behavior of the elements that influence its solution was studied. The results showed deficiencies and non-compliance with the legislation and lack of attention to the problem by the responsible institutions. As a conclusion, the need for the conscious application of the provisions, the operation of the System and its instruments, the allocation of the necessary budget and above all, increase the prevention work and the initiative to adopt practical solutions at the level of the autonomous government of the territory.
Influence of preparation of silver nanoparticles in carriers based on polymer/inorganic hybrids on the mineral composition of chicken eggs
Authors: Shevchenko L. V. , Dovbnia Y. Y. , Zheltonozhskaya T. B. , Permyakova N. М. , Shulyak S. V.
Published: January 2022

The solution to the problem of reducing the use of antibiotics in the production of edible eggs is possible through the development and use of alternative bactericidal preparations, including those based on nanosilver. Obtaining biocompatible and biodegradable polymer/inorganic carriers of nanosilver provides for the study of its cumulative qualities which determine the safety of edible chicken eggs. The study investigated the mineral composition of edible eggs when feeding Hy-Line W36 laying hens solutions of the nanosilver preparation in carriers based on polymer/inorganic hybrids (AgNPs/SPH) given in the concentrations of 0, 1.0, and 2.0 mg/L of water (0, 0.2 and 0.4 mg/hen per day) three times at 10 day intervals. Oral administration to laying hens of an aqueous solution of silver nanoparticles in carriers based on polymer/inorganic hybrids at doses of 0.2 and 0.4 mg per hen per day in a dose-dependent manner increased the silver content and did not significantly affect the content of copper, zinc, iron, and lead in the eggshell. The preparation of silver nanoparticles did not affect the content of silver, copper, zinc, iron and lead in the albumen and yolk of chicken eggs after the first and second application, and after the third treatment of laying hens contributed to an increase in the silver content in the egg albumen and yolk but did not affect the content in them of copper, zinc, iron and lead. A single feeding of a solution of a preparation of nanosilver in carriers based on polymer/inorganic hybrids to hens at doses of 0.2 and 0.4 mg per hen per day after 10 days, contributed to a significant increase in the yolks of chicken eggs due to a decrease in the albumen and eggshell. The second and third application of nanosilver to poultry in the indicated doses contributed to a decrease in its proportion in the albumen and in the yolk due to a significant increase in its proportion in the shell. Selective accumulation of in-shell silver can be a promising means of improving the safety and security of chicken eggs when they are microbially contaminated. The results of using nanosilver based on polymer/inorganic hybrids in laying hens can be the basis for the development of methods for increasing the bactericidal properties of the shell and the safety of edible eggs.
Comparative flower morphology of Agapanthus africanus and A. praecox (Amaryllidaceae)
Authors: Fishchuk O. S.
Published: January 2022

The structure of Agapanthus africanus and A. praecox flowers was studied on permanent cross-sectional and longitudinal sections using a light microscope. The genus Agapanthus belongs to the subfamily Agapanthoideae, the family Amaryllidaceae, which is characterized by the presence of the upper ovary, septal nectaries and fruit – fleshy capsule. Micromorphological studies of the flower are considered as a way for detection of unknown plant features, adjustment of plants to specialized ways of pollination and determining the first stages of morphogenesis of fruit, and further use these features in taxonomy. 10 flowers of A. africanus and A. praecox were sectioned using standard methods of Paraplast embedding and serial sectioning at 20 micron thickness. Sections were stained with Safranin and Astra Blau and mounted in Eukitt. It was found that in the studied species the tepals have single-bundle traces. The vascular system of the superior ovary consists of a three bundle dorsal vein, of the ventral roots complex, which are reorganized into paired ventral bundles of the carpel, which form traces to ovules. For the first time, the following gynoecium zones were detected in A. africanus: a synascidiate structural zone with a height of about 560 μm and a fertile symplicate structural zone with a height of about 380 μm and a hemisymplicate zone of 2580 μm. In A. praecox gynoecium, there is a synascidiate structural zone with a height of 200 μm and a symplicate structural zone of 600 μm and a hemisymplicate zone of 620 μm. Septal nectaries appear in the hemisymplicate zone and open with nectar fissures at the base of the column, with a total septal nectar height of 2880 μm in A. africanus and 820 μm in A. praecox. The ovary roof is 300 µm in A. africanus and 200 µm in A. praecox. Triple dorsal bundles of carpels in A. africanus have been identified, which could be considered as adaptation of different stages of morphogenesis of fruit to dehiscence. The new data obtained by the vascular anatomy of the flower and the presence of different ovary zones significantly add to the information about anatomical and morphological features of the studied species, which can be further used in the taxonomy of the family Amaryllidaceae.
Differential diagnosis of Dirofilaria immitis nematodes (Nematoda, Onchocercidae)
Authors: Kryvoruchenko D. , Prykhodko Y. , Mazannyі O. , Titarenko O. , Reva I. , Sherstiuk L.
Published: January 2022

Heartworm disease is a widespread anthropozoonotic disease of carnivorous animals, as well as humans. It is caused by nematodes belonging to the suborder Filariata, family Onchocercidae, genus Dirofilaria. There are about 26 species of heartworms in nature, the most common and pathogenic species in dogs and cats in most countries is Dirofilaria immitis Leidy, 1856. Mature helminths parasitize in the right ventricle and pulmonary arteries, large veins of animals and cause heart and vascular disorders, and death. Therefore, the aim of the study was to investigate the features of morphological and metric structure of adult nematodes of D. immitis isolated from the heart of dogs. Morphological studies have shown that in males the most characteristic differential features are the presence of two unequal spicules, specifically positioned relative to each other, as well as well-defined preanal and less pronounced adanal and postanal papillae. In female heartworms, the characteristic morphological features are the shape and location of the vulva. There is a difference in the structure of the esophagus in males and females. In females, the anterior and posterior parts of the esophagus are well expressed, with enlargements, in males these divisions are not pronounced. To increase the efficiency of species identification of D. immitis nematodes, it is proposed to use metric parameters that characterize the overall body size, body and width of esophagus in different areas, length of esophagus, and the location of the nerve ring. In males, 11 indicators are also suggested that characterize the size of the spicules and the location of the cloaca. In females, seven additional parameters are pointed out that characterize the location of the vulva, anus and body width in these areas. The obtained data expand the already existing data on the peculiarities of the morphological structure of parasitic nematodes of the species D. immitis and their identification.
Prognostic markers of canine mammary tumours: Retrospective study of 142 cases
Authors: Kovalenko M. S. , Bilyi D. D. , Skliarov P. M. , Maslikov S. N. , Suslova N. I. , Spitsyna T. L. , Yevtushenko I. D.
Published: January 2022

Due to relevance of the problem, prediction of biological behaviour of neoplasias in mammary glands of dogs requires using contemporary approaches to the study, first of all, of ways of dissemination of tumour cells. One of them is studying the mechanisms of migration of cancer cells out of the neoplasm tissues with further dissemination and development of metastatic sites in the regional lymphatic nodes and remote tissues. We studied the survival period of bitches with tumours of the mammary glands following regional or unilateral mastectomy. Among malignant mammary tumours in bitches, the most often diagnosed were single tumours (57.5%), which histologically were classified to carcinomas – ductal (26.9%) and mixed type (21.9%). Probability of intratumoral invasion to blood vessels equaled 12.0%, to lymph vessels – 7.8%, lymph nodes – 12.8%. It depends on the histological type of the tumour, the most aggressive potentially being сomedocarcinoma, tubulopapillary carcinoma and ductal carcinoma. Parameters of life expectancy and survival level after mastectomy depend on clinical stage of the disease (increase in the stage from the first to the third was characterized by decrease from 12.8 ± 9.5 to 9.4 ± 7.8 months), presence of angio/lymphatic invasions, presence of angiolymphatic invasion, but had no correlation with the size of the tumours. An important predictor of tumour-related death of dogs suffering neoplasias of the mammary glands is index vet-NPI, which has significant correlation with the clinical stage according to Owen and median survival. In particular, median survival in patients with the index lower than 4 exceeded the corresponding values in dogs with the index above 4 by 1.3 times. A promising direction of further research would be studying biological mechanisms of development of tumour emboli in the blood and lymph vessels, metastatic sites in lymph nodes, and also determining their role in pathogenesis of canine mammary tumours.
Elimination of the toxic effect of copper sulfate is accompanied by the normalization of liver function in fibrosis
Authors: Bozhkov A. I. , Bozhkov A. A. , Ponomarenko I. E. , Kurguzova N. I. , Akzhyhitov R. A. , Goltvyanskii A. V. , Klimova E. M. , Shapovalov S. O.
Published: January 2022

The search for biologically active compounds that regulate liver function in fibrosis is an urgent medical and biological problem. A working hypothesis was tested, according to which low molecular weight biologically active compounds from Pleurotus ostreatus and Sacharamirses cerevisiae are capable of exerting immunomodulatory and antitoxic effects after intoxication of the body with ions of heavy metals, in particular copper sulfate. Elimination of the toxic effect caused by copper sulfate can also ensure the normalization of liver function in various pathologies, in particular with liver fibrosis. When determining toxicity, a study was carried out on Wistar rats, and when studying the effect of low molecular weight biologically active compounds on liver function, clinical trials were carried out on volunteers. The activity of alanine aminotransferase, aspartate aminotransferase, actonitase and glutathione peroxidase, as well as the content of bilirubin and lipid hydroperoxides were determined. It was shown that preliminary administration of biologically active compounds to rats at a dose of 0.05 mL/100 g of body weight provided the formation in some animals (up to 80%) of resistance to the toxic effect of copper sulfate (dose 2.5 mg/100 g of body weight). Such stability is associated with a shift in the balance of “prooxidants-antioxidants” towards antioxidants. The data obtained in the clinic on volunteers with liver fibrosis and hepatitis also testify in favour of the membranotropic action of biologically active compounds. Biologically active compounds provided a decrease or complete restoration of the activity of transferases (ALT and AST) in the blood serum of these patients, with the exception of one patient out of 20 examined. Our experiment has shown the relationship between the elimination of toxicity to the action of copper sulfate and the normalization of liver function in patients. The results obtained indicate that it will be promising to use a complex of low molecular weight components from P. ostreatus and S. cerevisiae as an antidote and hepatoprotective agent.
Biological responses in Musca domestica to fipronil and chlorfenapyr exposures
Authors: Shumilova P. A. , Sennikova N. A. , Silivanova E. A. , Levchenko M. A.
Published: January 2022

Insect populations exist under acute and chronic exposures to lethal and sublethal insecticide concentrations. Among the sublethal effects of insecticides on insects are reductions in life span, development rates, population growth, fertility, fecundity, changes in sex ratio, deformities, changes in behaviour, feeding, searching, and oviposition. These effects may differ depending on the modes of action of insecticides, their doses, and developmental stage of application. This study evaluated the life-history parameters in Musca domestica Linnaeus, 1758 (Diptera:Muscidae) strains that were exposed to two insecticides (fipronil and chlorfenapyr) with different modes of action at sublethal concentrations in each generation up to tenth. Two approaches to each insecticide’s exposure were used in this study, particularly in one approach, only adults M. domestica were exposed to fipronil or chlorfenapyr and in another approach, only larvae were exposed to each insecticide. The susceptibility of adult flies to these insecticides was assessed by resistance ratio based on results of non-choice feeding bioassays. Fipronil exposure at the sublethal concentration in each generation did not affect the susceptibility of adult M. domestica (in the tenth generation) to fipronil. The resistance ratio values revealed tolerance to chlorfenapyr in adults of M. domestica strains that were exposed to this insecticide, independent of the approach used to insecticide exposure. Most of the life-history parameters (such as durations of separate developmental stages, the emergence duration, the adult emergence ratio, the female ratio, and the number of eggs per female per day) of the second, fourth, sixth, eighth, and tenth generations of the insecticide-exposed strains were similar to those of the control strain. At the same time, the sublethal effects of both insecticides fipronil and chlorfenapyr prolonged the larval duration (1.63–2.22 times) and the number of days from egg to adult (1.18–1.39 times) compared to the control strain. Further studies are needed to investigate a possible genetic variability in M. domestica in response to exposure of parental generation to sublethal doses of fipronil and chlorfenapyr.
Morphological signs of myopathy in pork that show no drastic decrease in pH after slaughter
Authors: Semenova A. A. , Kuznetsova T. G. , Nasonova V. V. , Loskutov S. I. , Nekrasov R. V. , Bogolyubova N. V.
Published: January 2022

High pH value 45 minutes after slaughter (рН45) has so far been the most frequently used indicator to select pig carcasses with normal course of autolysis. However, in practice, this does not provide meat quality homogeneity. Therefore, carcasses with рН45 > 6.0 were examined for signs of myopathy, which are characteristic for PSE meat, using the histological method. To perform the study, we randomly selected 320 individuals for slaughter out of 1,059 individuals of mixed swine grown in the same conditions. After slaughter, we selected 18 fresh carcasses that demonstrated low рН45. The results of the examination of the muscular tissue (L. dorsi) samples revealed that pork varied in microstructural characteristics. Only 44% of the samples had no signs of myopathy: no contracture nodes and destructive changes in the muscle fibers were present. A total of 39% of the samples were identified to the muscular tissue with mildly expressed myopathy, 17% of the samples – to the muscular tissue with acute myopathy. Thus, among the carcasses with рН45 > 6.0, 56% of the carcasses had signs of mild and acute myopathy, which explains quality homogeneity of meat selected using this criterion. Statistical analysis of the results suggested that the increase in the diameter of the muscle fibers of glycolytic type was related to appearance of signs of mild and acute myopathy – “giant fibers”. Increase in the weight of animals is not a risk factor. The obtained results allowed us to conclude the necessity of developing new approaches to assessing meat quality immediately after the slaughter with the purpose of increasing efficiency in predicting technological properties of meat. Promising directions of developing quick methods in histology allow us to hope that such approaches may be based on the data on microstructure of fresh muscular tissue.
Dose-dependent effect of chronic exposure to lead acetate on the dynamics of the content of delta-aminolevulinic acid and essential trace elements in the serum of laying hens
Authors: Dotsenko E. , Paliy А. , Morozenko D. , Dotsenko R. , Zemlianskyi А. , Pavlichenko O.
Published: January 2022

One of the most global and dangerous pollutants is considered to be lead, due to its ability to accumulate in living organisms, to be included in the metabolic cycle, to form highly toxic organometallic compounds, not being biodegradable. To study the chronic effects of lead acetate, an experiment was performed on laying hens of Lohmann Brown cross. For research, one control and three experimental groups were formed, 20 chickens in each. Birds of the experimental groups were administered lead acetate daily with compound feed in doses (in terms of metal): Group I – 50 mg/kg of feed, II – 75 mg/kg of feed, III – 150 mg/kg of feed. Access to water was not restricted. The birds of the control group received a complete diet without lead acetate. On the 30th, 90th, 120th days of the experiment and the 20th day after withdrawal of the toxicant (the 140th day of the experiment), we took blood samples from birds for biochemical and toxicological studies. The concentration of delta-aminolevulinic acid (δ-ALA) in the serum of laying hens was determined by reversed-phase high-performance liquid chromatography. Determination of the content of lead in the serum of laying hens was performed by X-ray fluorescence analysis. The concentration of total calcium, inorganic phosphorus, and magnesium in the serum of the laying hens was determined using production kits. We detected the dose-dependent chronic effect of lead acetate on the dynamics of the content of delta-aminolevulinic acid and essential trace elements in the serum of laying hens. The administration of lead acetate into the body of productive poultry for 120 days in doses of 50, 75, and 150 mg/kg with feed did not cause visible clinical signs of poisoning, but caused a violation of porphyrin metabolism, manifested in a reliable increase in the concentration of delta-aminolevulinic acid in serum on the 30th, 90th and 120th days of the experiment. It has been experimentally proven that the administration into the body of laying hens of lead acetate in doses of 50, 75 and 150 mg/kg of feed for 120 days leads to the maximum accumulation of lead in the serum on the 30th, 90th, and 120th days of the experiment. Prolonged administration of lead acetate to laying hens at high concentrations is characterized by a reliable decrease in the content of total calcium, inorganic phosphorus and magnesium in the serum of laying hens and a reliable increase in the content of ferrum. In the future it is necessary to study the intensity of lipid peroxidation processes in laying hens under chronic exposure to lead acetate.
Сondition of urogenital tract microbiotes and pro- and antioxidant system in male azoospermia
Authors: Vorobets M. Z. , Melnyk O. V. , Kovalenko I. V. , Fafula R. V. , Borzhievsky A. T. , Vorobets Z. D.
Published: January 2022

Over the past 20 years, there has been a clear trend to increase in the number of infertile men in Ukraine, their percentage reaches 50% in infertile couples. There is a significant percentage of male infertility caused by azoospermia – the lack of sperm in the ejaculate. In male infertility, azoospermia is found in 10–15% of patients, among other forms of pathospermia. Given the ambiguity of ideas about the etiology, pathogenesis and treatment and diagnostic approaches for various types of infertility, it remains important to clarify the relationship of urogenital infections with the regulatory systems of cells, including the state of the pro- and antioxidant system and the search for additional markers. 119 patients with various forms of azoospermia were examined. All patients underwent the following studies: spermogram, infectious screening, inhibin B, lipid peroxidation, activity of enzymes of the glutathione antioxidant system in sperm plasma and blood serum. Infectious screening included analysis of urethral secretions, bacteriological examination of sperm or prostate secretion, assessment of the species and quantitative composition of the microflora of the male urogenital tract. According to the results of spermogram and other diagnostic methods, a non-obstructive form of azoospermia was detected in 69 patients. In obstructive azoospermia, ejaculate as such was absent. It is suggested that inhibin B may be an important medical diagnostic test for azoospermia. As a result of the conducted researches the importance of determining the concentration of inhibin B as a marker of azoospermia was demonstrated and a negative correlation of moderate strength between the content of inhibin B and testosterone level in the plasma of men with non-obstructive azoospermia was revealed. It was found that Ureaplasma pervum and Ureaplasma urealyticum infect the male genitourinary system to the greatest extent among a number of microorganisms, both in non-obstructive and obstructive forms of azoospermia. Enterococcus faecalis is more pronounced in the sperm fluid in the non-obstructive form of azoospermia and prostate secreton in the obstructive form of azoospermia. In the non-obstructive form of azoospermia in the seminal plasma and serum, the processes of lipid peroxidation intensify, the concentration of reduced glutathione decreases and the activities of the enzymes of the glutathione antioxidant system (glutathione peroxidase and glutathione transferase) decrease. It can be considered that an important diagnostic test for the nonobstructive form of azoospermia is the ratio of reduced glutathione to oxidized glutathione in sperm plasma.
Teleoperated Service Robot with an Immersive Mixed Reality Interface
Authors: Nakayama Angelica , Ruelas Daniel , Savage Jesus , Bribiesca Ernesto
Published: January 2022

Teleoperated service robots can perform more complex and precise tasks as they combine robot skills and human expertise. Communication between the operator and the robot is essential for remote operation and strongly affects system efficiency. Immersive interfaces are being used to enhance teleoperation experience. However, latency or time delay can impair the performance of the robot operation. Since remote visualization involves transmitting a large amount of video data, the challenge is to decrease communication instability. Then, an efficient teleoperation system must have a suitable operation interface capable of visualizing the remote environment, controlling the robot, and having a fast response time. This work presents the development of a service robot teleoperation system with an immersive mixed reality operation interface where the operator can visualize the real remote environment or a virtual 3D environment representing it. The virtual environment aims to reduce the latency on communication by reducing the amount of information sent over the network and improve user experience. The robot can perform navigation and simple tasks autonomously or change to the teleoperated mode for more complex tasks. The system was developed using ROS, UNITY 3D, and sockets to be exported with ease to different platforms. The experiments suggest that having an immersive operation interface provides improved usability for the operator. The latency appears to improve when using the virtual environment. The user experience seems to benefit from the use of mixed reality techniques; this may lead to the broader use of teleoperated service robot systems.
Method for Estimating Time of Wireless Transfer of Energy Resources Between Two Robots
Authors: Erashov Aleksei , Kamynin Konstantin , Krestovnikov Konstantin , Saveliev Anton
Published: January 2022

The energy capacity of the batteries used as the main power source in mobile robotic devices determines the autonomous operation of the robot. To plan the execution of tasks by a group of robotic tools in terms of time consumption, it is important to take into account the time during which the battery of each individual robot is charged. When using wireless power transfer, this time depends on the efficiency of the power transfer system, on the power of the transferring part of the system, as well as on the level of charge required to recharge. In this paper, we propose a method for estimating the time of transfer of energy resources between two robots, taking into account these parameters. The proposed method takes into account the application of the algorithm for the final positioning of robots, the assessment of linear offsets between robots, includes the calculation of efficiency, as well as the determination of the battery charge time, taking into account the parameters obtained at the previous stages of the method. The final positioning algorithm for robots uses algorithms for processing data from a robot vision system to search for fiducial markers and determine their spatial characteristics to ensure the final positioning of mobile robotic platforms. These characteristics are also used to determine the linear offsets between robots, on which the efficiency of energy transfer depends. To determine it, the method uses a mathematical model of the energy characteristics of the wireless power transfer system and the obtained linear offsets. At the last stage of the method, the time for charging the battery of the mobile robot is calculated, taking into account the data from the previous stages. Application of the proposed method to simulate the positioning of robots in a certain set of points in the working space will reduce the time spent on charging the robot battery when using wireless power transfer. As a result of the simulation, it was determined that the transfer of energy resources between robots took place with an efficiency in the range from 58.11% to 68.22%, and out of 14 positioning points, 3 were identified with the shortest energy transfer time.
Underwater Robot Manipulator Control
Authors: Balabanov Alexey , Bezuglaya Anna , Shushlyapin Evgeny
Published: January 2022

This paper deals with the problem of bringing the end effector (grip center) of an underwater vehicle anthropomorphic manipulator to a predetermined position in a given time using the terminal state method. A dynamic model with the account of joint drives dynamics is formulated on the basis of obtained kinematic model constructed by using the Denavit-Hartenberg method (DH model). The DH model is used in a terminal nonlinear criterion that displays estimate of the proximity of the effector's orientation and position to the specified values. The dynamic model is adapted for effective application of the author's terminal state method (TSM) so that it forms a system of differential equations for the rotation angles of manipulator links around the longitudinal and transverse axes, having only desired TSM-controls in the right parts. The converted model provides simplifications of controls calculation by eliminating the numerical solution of special differential equations, that is needed in the case of using in TSM nonlinear dynamic models in general form. The found TSM-controls are further used in expressions for control actions on joints electric drives obtained on the basis of electric drives dynamic models. Unknown drives parameters as functions of links rotation angles or other unknown factors, are proposed to be determined experimentally. Such two-step procedure allowed to get drive control in the form of algebraic and transcendental expressions. Finally, by applying the developed software, simulation results of the manipulator end effector moving to the specified positions on the edge of the working area are presented. The resulting error (without accounting measurement error) does not exceed 2 centimeters at the 1.2 meters distance by arm reaching maximum of length ability. The work was performed under the Federal program of developing a robotic device for underwater research in shallow depths (up to 10 meters).
Synthesis of Line of Sight Angle Coordinate Filter on the Basis of Interactive Multi-Model Evaluation Algorithm
Authors: Trung Dang , Tuan Nguyen , Bang Nguyen , Tuyen Tran
Published: January 2022

On the basis of the tracking multi-loop target angle coordinate system, the article has selected and proposed a interactive multi-model adaptive filter algorithm to improve the quality of the target phase coordinate filter. In which, the 3 models selected to design the line of sight angle coordinate filter; Constant velocity (CV) model, Singer model and constant acceleration model, characterizing 3 different levels of maneuverability of the target. As a result, the evaluation quality of the target phase coordinates is improved because the evaluation process has redistribution of the probabilities of each model to suit the actual maneuvering of the target. The structure of the filters is simple, the evaluation error is small and the maneuvering detection delay is significantly reduced. The results are verified through simulation, ensuring that in all cases the target is maneuvering with different intensity and frequency, the line of sight angle coordinate filter always accurately determines the target angle coordinates.