An initial boundary-value problem for model electromagnetoelasticity system

AbstractIn this paper we consider an initial boundary-value problem related to the electrodynamics of vibrating elastic media. The aim is to prove an existence and uniqueness result for a model describing the nonlinear interactions of the electromagnetic and elastic waves. We assume that the motion of the continuum occurs at velocities that are much smaller than the propagation velocity of the electromagnetic waves through the elastic medium. The model under study consists of two coupled differential equations, one of them is the hyperbolic equation (an analog of the Lamé system) and another one is the parabolic equation (an analog of the diffusion Maxwell system). One stability result is proved too

Toxic organizational environment on the Italian and Russian enterprises: an inter-country comparison

The concept of the organizational toxicity, which is considered by authors to be the phenomena of social pollution, is based on the study and synthesis of research results on the destructive aspects of the culture and working environment inside the organization. Toxic elements of the organizational environment have a negative impact on employees and cause a deterioration in their health and well-being that ultimately leads to a decrease in the efficiency of the use of human resources, in particular, and financial losses as a whole. Thus, there is underestimated the social aspect of a negative impact of the organization's economic activities on psychosocial health at work. The given research deals with the issue of the organizational toxicity, ex- pressed in reducing the level of well-being and deterioration of physical and psychosocial health of workers caused by the economic activities of the company. The theoretical study has allowed us to formulate hypoth- eses about the toxic management practices and their negative impact on workers’ psychosocial health. An empirical study conducted by the authors in comparison between Russian and Italian companies has permit- ted to verify the given hypotheses: to examine in detail the nature of the organizational toxicity and to identify toxic elements of the socio-labour relations in the company. An important feature of the current research is studying the toxic elements of working environment from the employers and employees points of view. The comparative studies possess an increasingly important cognitive function in the development of theories of labour and the science of management, as well as their practical applications. Inter-country comparisons allow us to approach the problem from a more common position, to the disclosure mechanisms of action, as well as forms of manifestation of separate regularities in various socio-economic systems

Formation of Chitosan Nanofibers by Electrospinning Method

The paper presents the results of the preparation of the nanofiber coatings from chitosan biopolymer by electro-spinning. Structure and uniformity distribution of the fibers in the resulting coatings are investigated by a scanning electron microscope JEOL JSM-5610 LV. The optimum concentration of the chitosan solution in the mold, which provide forming nanofibers with fewer defects, was determinated. The obtained data are used for the development of the technology for production of hemostatic and wound-healing dressings for medical purposes in order to organize their production at OJSC "Mineral Wax Plant"

Properties of Elastomeric Compositions with Highly Dispersed Carbon Additives

The effect of highly dispersed carbon additives (HDCA) obtained in high-voltage discharge plasma on properties of elastomeric compositions is investigated. Some tests to determinate tensile strength, stretching strain, abrasion resistance, hardness and resistance to heat aging of highly filled rubbers based on raw rubber for general and special application are carried out. It is shown that HDCA addition permits to improve performance characteristics of elastomers based on butadiene-acrylonitrile rubber

A model for A=3 antinuclei production in proton-nucleus collisions

A simple coalescence model based on the same diagrammatic approach of antimatter production in hadronic collisions as used previously for antideuterons is used here for the hadroproduction of mass 3 antinuclei. It is shown that the model is able to reproduce the existing experimental data on Tbar and 3hebar production without any additional parameter.Comment: 7 figures. submitted to Eur. Phys. J.

Formation of Chitosan Nanofibers by Electrospinning Method

The paper presents the results of the preparation of the nanofiber coatings from chitosan biopolymer by electro-spinning. Structure and uniformity distribution of the fibers in the resulting coatings are investigated by a scanning electron microscope JEOL JSM-5610 LV. The optimum concentration of the chitosan solution in the mold, which provide forming nanofibers with fewer defects, was determinated. The obtained data are used for the development of the technology for production of hemostatic and wound-healing dressings for medical purposes in order to organize their production at OJSC "Mineral Wax Plant"

Post-hepatectomy liver failure – achievements and challenges

Institutul de chirurgie ”A.V.Vishnevskii”, Moscova, Rusia, Al XII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova cu participare internațională 23-25 septembrie 2015Introducere: Problema insuficienţei hepatice postrezecţionale (IHPR) rămîne a fi în prezent una destul de actuală. Frecvenţa IHPR nu este în descreştere, oscilînd în limitele 0,7-0,9%. În acelaşi timp introducerea de noi tehnologii în domeniul diagnosticării IHPR poate îmbunătăţi rezultatele tratamentului chirurgical al pacienţilor cu tumori hepatice. Scopul: Studierea posibilităţilor de diagnostic precoce și tratament a IHPR la pacienţii care au suportat intervenţii chirurgicale majore hepatice. Material şi metode: Timp de 5 ani au fost efectuate 204 rezecţii hepatice majore. Pe motivul afectării hepatice secundare au fost operaţi 101 (49,6%) pacienţi, dintre care 75 (36,8%) pacienţi cu metastaze de cancer colorectal; tumori hepatice primare – 54 (26,4%) pacienţi, dintre care 25 (12,3%) – carcinom hepatocelular, 20 (9,8%) – colangiocarcinom, 49 (24%) – tumori benigne şi afecţiuni non-tumorale hepatice. Structura operaţiilor efectuate: hemihepatectomia stîngă – 42 (20%), hemihepatectomia dreaptă – 68 (33,3%), hemihepatectomia stîngă extinsă – 27 (13,3%), hemihepatectomia dreaptă extinsă – 44 (21,5%), rezecţia ≥3 segmente hepatice – 19 (16,3%). În perioada postoperatorie au fost estimaţi indicatorii insuficienţei hepatice în baza datelor clinice, scăderea nivelului de albumină <28 g/l, creşterea bilirubinei ˃50 μmol/l, scăderea indicelui protrombinei (IP) <50%, creşterea INR peste 2,0 în 1-3-a, 7-9-a şi a 5-a zi postoperatorie (criteriul 50/50). Pentru aprecierea gradului de IHPR s-a utilizat clasificarea ISGLS. Rezultate: Majoritatea pacienţilor operaţi au prezentat la 1-3-a zi postoperatorie scăderea nivelului de albumină şi IP, creşterea bilirubinei şi INR. În acelaşi timp, schimbări simultane semnificative ale acestor parametri au fost observate la 64 (31,4%) pacienţi. Aceste modificări s-au rezolvat în urma tratamentului conservativ în termen de 4-8 zile, astfel încît nu au putut fi considerate IHPR. La ziua a 5-a aceste modificări erau observate la 48 (23,5%) pacienţi. Valorile numerice ale parametrilor estimaţi au fost în limitele: albumina – 17-34 (media 29) g/l, INR – 1,4-3,8 (media 2,5), bilirubina totală – 22-99 (media 49) μmol/l. La 31 (15,2%) pacienţi semnele IHPR au cedat în urma terapiei standard, ce a fost interpretat ca clasa A de insuficienţă hepatică după ISGLS. IHPR clinic semnificativă s-a observat la 17 (8,3%) pacienţi, dintre care 11 (5,4%) – clasa B şi 6 (2,9%) – clasa C după ISGLS. Cu toate acestea criteriul 50/50 a fost pozitiv doar la 12 (5,9%) pacienţi. Pe fundalul progresării IHPR au decedat 8 (4,1%) pacienţi, dintre care 3 (1,5%) cu criteriul 50/50 negativ. Concluzii: În pofida ameliorării rezultatelor tratamentului chirurgical al tumorilor hepatice, o problemă importantă rămîne a fi depistarea precoce şi profilaxia apariţiei IHPR. Perfecţionarea metodelor de diagnostic precoce şi prognostic al dezvoltării IHPR la etapa preoperatorie va permite nu doar scăderea letalităţii, dar va spori deasemenea posibilităţile chirurgiei hepatice.Introduction: The issue of posthepatectomy liver failure (PHLF) continues to be very actual. The frequency of the PHLF does not tend to decrease, and varies between 0.7-9.1%. However, the introduction of new technologies in the field of diagnosis of PHLF can improve the results of surgical treatment of patients with liver tumors. Aim of study: To study the possibilities of early diagnosis and treatment of PHLF after major hepatic resection. Material and methods: During 5 years were performed 204 major hepatic resections. 101 (49.6%) patients had secondary hepatic injury – 75 (36.8%) patients with metastases of colorectal cancer; 54 (26.4%) patients had primary liver tumors, including 25 (12.3%) – hepatocellular carcinoma, 20 (9.8%) – cholangiocarcinoma, 49 (24%) – benign tumors and non-tumoral liver diseases. Surgical interventions: left hepatectomy – 42 (20%), right hepatectomy – 68 (33.3%), extended left hepatectomy – 27 (13.3%), extended right hepatectomy – 44 (21.5%), resection of ≥3 segments of liver – 19 (16.3%). In postoperative period, the signs of PHLF were evaluated on clinical data, reduced albumin below 28 g/L, elevated bilirubin levels higher than 50 μmol/l, lower prothrombin index (PTI) below 50%, increasing of INR above 2 at the 1-3 and 7-9-th and 5-th postoperative day (criterion 50/50). To assess the degree of liver failure the ISGLS classification was used. Results: At 1-3 postoperative days most surgical patients presented the decreased levels of albumin and IP, increased bilirubin and INR levels. At the same time, significant simultaneous changes in these parameters were seen in 64 (31.4%) patients. These changes were solved by conservative treatment within 4-8 days, so they could not be considered as PHLF. At the 5-th day, these changes were seen in 48 (23.5%) patients. The numerical values of the estimated parameters ranged: albumin – 17- 34 (average 29) g/L, INR – 1.4-3.8 (average 2.5), total bilirubin – 22-99 (average 49) μmol/L. In 31 (15.2%) cases the signs of PHLF were solved by standard therapy, which was interpreted as a Class A liver failure (ISGLS). Clinically significant PHLF occurred in 17 (8.3%) patients, including 11 (5.4%) – class B and 6 (2.9%) – class C (ISGLS). However, only 12 (5.9%) patients had positive 50/50 criterion. IHPR progression led to the death in 8 (4.1%) cases, of which 3 (1.5%) with negative 50/50 criterion. Conclusions: Despite the amelioration of the surgical treatment of liver tumors, an important problem remains early detection and prevention of the PHLF occurrence. Improved methods of early diagnosis and prediction of PHLF development in preoperative stage will not only reduce mortality, but will also enhance them opportunities of liver surgery