The study of influence of nitrogen containing rosin adducts derivatives on technical properties of elastomeric compounds

The following substances were used as additives: maleated rosin modified with oleic acid, containing maleopimaric acid ( ≈50%) which did not react with maleic anhydride rosin acids; rosin-itaconic ac-id adduct, containing up to ≈50% of citraconopimaric acid as a mixture of two isomers; octylimide of rosin-itaconic acid adduct; imide of maleated rosin and aniline, containing up to ≈50% of N-phenylimide of maleopimaric acid; imidoamide of maleated rosin and aniline, containing maleo-pimaric acid anilide N-phenylimide; imidoamide of maleated rosin and p-anisidine, containing maleopimaric acid p-methoxyphenylamide N-( p-methoxyphenyl)imide. Their uses as processing aids in rubber compounds based on synthetic isoprene rubber are considered. Processing parameters, such as Mooney viscosity, scorch resistance, kinetic characteristics of vulcanization of the rubber mixtures with nitrogen adducts of rosin are investigated

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

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.

Imide-Containing Compositions for Tribotechnical Coatings Based on Polytetrafluoroethylene

Results of the experimental studies on the development of the compositions of composite tribotechnical materials based on polytetrafluoroethylene modified with imide-containing reagents with enhanced parameters of the stress–strain and tribotechnical characteristics and conventional production and processing technology are presented. The developed compositions can be used for the fabrication of products for structural and tribotechnical use applied in the friction joints of machines, mechanisms, and process equipment without external lubrication

The PHENIX Experiment at RHIC

The physics emphases of the PHENIX collaboration and the design and current status of the PHENIX detector are discussed. The plan of the collaboration for making the most effective use of the available luminosity in the first years of RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program available at http://www.rhic.bnl.gov/phenix

Controlled mobility in stochastic and dynamic wireless networks

We consider the use of controlled mobility in wireless networks where messages arriving randomly in time and space are collected by mobile receivers (collectors). The collectors are responsible for receiving these messages via wireless transmission by dynamically adjusting their position in the network. Our goal is to utilize a combination of wireless transmission and controlled mobility to improve the throughput and delay performance in such networks. First, we consider a system with a single collector. We show that the necessary and sufficient stability condition for such a system is given by ρ<1 where ρ is the expected system load. We derive lower bounds for the expected message waiting time in the system and develop policies that are stable for all loads ρ<1 and have asymptotically optimal delay scaling. We show that the combination of mobility and wireless transmission results in a delay scaling of Θ([1 over 1−ρ]) with the system load ρ, in contrast to the Θ([1 over (1−ρ)[superscript 2]]) delay scaling in the corresponding system without wireless transmission, where the collector visits each message location. Next, we consider the system with multiple collectors. In the case where simultaneous transmissions to different collectors do not interfere with each other, we show that both the stability condition and the delay scaling extend from the single collector case. In the case where simultaneous transmissions to different collectors interfere with each other, we characterize the stability region of the system and show that a frame-based version of the well-known Max-Weight policy stabilizes the system asymptotically in the frame length.National Science Foundation (U.S.) (Grant CNS-0915988)United States. Army Research Office. Multidisciplinary University Research Initiative (Grant W911NF-08-1-0238