5 research outputs found
ELECTRORHEOLOGICAL BEHAVIOR OF SUSPENSIONS BASED ON POLYDIMETHYLSILOXANE FILLED WITH HALLOYSITE
No full textThe rheological behavior at 20 °С of electrorheological fluids based on silicone oil filled with halloysite nanotubes with different water content was studied. Flow and viscosity curves, storage and loss moduli were measured using a cylinder-cylinder rotary viscometer. The frequency dependences of electrical conductivity and dielectric loss tangent were obtained by dielectric spectroscopy. When an electric field is applied to the samples, their rheological behavior changes - the values of the yield stress increase. In this case, the viscosity curves exhibit an elastic behavior at low shear stresses and exhibit a Newtonian flow when the yield point is overcome. The frequency dependences of the storage and loss moduli confirm the results obtained on the flow curves. The electric field intensity influence on the magnitude of the electrorheological effect was also investigated. The effect of water presence on electrorheological and electrophysical properties was shown. Electrorheological fluid with a small amount of water exhibits a better response to the electric field application, as evidenced by higher values of the yield stresses in comparison with the sample containing drained filler. The small water content does not have a strong effect on the electrical conductivity of the systems under study, but its presence significantly changes the form of the dielectric loss tangent - the contribution of the electrical conductivity to the relaxation processes is significant, and the nature of the relaxation transitions changes due to the different polarizabilities of the wet and dried filler. This work demonstrates the prospects of using nanoscaled fillers with a high aspect ratio as the dispersed phase for electrorheological fluids.Forcitation:Kuznetsov N.M., Belousov S.I., Bessonova N.P., Chvalun S.N. Electrorheological behavior of suspensions based on polydimethylsiloxane filled with halloysite. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 6. P. 41-47</jats:p
Conflicting patterns of thought in the Russian debate on transition: 2003-2007
No full textThis article is a continuation of two essays by the same author on Soviet/Russian economic debates between 1987 and 2002 published in Europe-Asia Studies in 2006 and 2007, so now the series of articles covers 20 years of Soviet/Russian discussions on economic reforms. Should Russia strive to become a 'Western' country marked by democracy and a market economy serving the individual interests of its citizens, or was it more important to become a great power again? Are Western patterns of political and economic life suitable for Russia or is the attempt to import foreign institutional structures doomed for failure, making it necessary for Russia to find her own way? This type of question, going far beyond the realm of economics, was and still is at the heart of the debate among Russian economists, which shall be discussed here, on the basis of a qualitative content analysis of the most important economic journals and selected monographs. --
Hepatic real-world outcomes with obeticholic acid in primary biliary cholangitis (HEROES): a trial emulation study design
No full text\ua9 2024 The Author(s). Background and aims: Primary biliary cholangitis (PBC) is a rare, progressive liver disease. Obeticholic acid (OCA) received accelerated approval for treating patients with PBC in whom ursodeoxycholic acid (UDCA) failed, based on a surrogate endpoint of reduction in alkaline phosphatase. Analysis of the long-term safety extension with 2 external control groups demonstrated a significant increase in event-free survival in OCA-treated patients. This fully real-world evidence study assessed the effect of OCA treatment on the clinical outcomes. Approach and results: This trial emulation used data from the Komodo Healthcare Map™ claims database linked to US national laboratory, transplant, and death databases. Patients with compensated PBC and intolerance/inadequate response to UDCA who initiated OCA therapy were compared with patients who were OCA-eligible but not OCA-treated. The primary endpoint was time to first occurrence of death, liver transplant, or hospitalization for hepatic decompensation, analyzed using a propensity-score weighted Cox proportional hazards model. Baseline prognostic factors were balanced using standardized morbidity ratio weighting. For the primary analysis, 4174 patients contributed 11,246 control index dates; 403 patients contributed OCA indexes. Weighted groups were well balanced. Median (95% CI) follow-up in the OCA and non-OCA arms was 9.3 (8.4–10.6) months and 17.5 (16.2–18.6) months (weighted population; censored at discontinuation). Eight events occurred in the OCA arm, 32 in the weighted control (HR=0.37; 95% CI=0.14–0.75; p<0.001). Effects were consistent for each component of the composite endpoint. Conclusions: We identified a 63% reduced risk of hospitalization for hepatic decompensation, liver transplant, or death in OCA-treated versus non–OCA-treated individuals
Ergonomics of Protective Clothing Proceedings of NOKOBETEF 6 and 1st European Conference on Protective Clothing held in Stockholm, Sweden, May 7-10, 2000
No full textThe European Directives on personal protective devices have increased the interest in protective and functional properties of work clothing and intensified standardisation work as well as stimulated research in areas with limited knowledge. There is a long tradition of research and information exchange in the Nordic countries on the subject. The NOrdisk KOrdineringsgruppe om BEskyttelseskläder som TEknisk Forebyggelsesmiddel (Nordic Coordination Group on Protective Clothing as a Technical Preventive Measure) was founded in 1984. NOKOBETEF is an independent society of professionals from the Nordic as well as other countries. NOKOBETEF has since its foundation organised symposia in Copenhagen (1984), Stockholm (1986), Gausdal, Norway (1989), Kittilä, Finland (1992), and Elsinor, Denmark (1997). The conferences have long had a good attendance from European countries and from overseas. The 6th Nokobetef conference was organised as the 1st European Conference on Protective Clothing to emphasize the European dimension. During the conference the European Society for Protective Clothing was founded. One of its first tasks will be to prepare for the 2nd conference to be held in Switzerland in 2003. The proceedings of this conference cover a broad spectrum of the subject protective clothing. Emphasis was given to the ergonomics aspects, which is in line with the present interest and priorities of the European standardisation bodies (CEN). A functional and comfortable use of protective clothing is a key element for a succesful implementation of this kind of preventive and protective measures in the workplaces. A total of 77 papers are presented in this book. They represent a qualified source of new, valuable and useful information for the advancement of the knowledge and the application of protective clothing
COBALT: A Confirmatory Trial of Obeticholic Acid in Primary Biliary Cholangitis With Placebo and External Controls
No full textCopyright \ua9 2024 The Author(s).Objectives: Obeticholic acid (OCA) treatment for primary biliary cholangitis (PBC) was conditionally approved in the phase 3 POISE trial. The COBALT confirmatory trial assessed whether clinical outcomes in PBC patients improve with OCA therapy. Methods: Patients randomized to OCA (5–10 mg) were compared with placebo (randomized controlled trial [RCT]) or external control (EC). The primary composite endpoint was time to death, liver transplant, model for end-stage liver disease score ≥15, uncontrolled ascites, or hospitalization for hepatic decompensation. A prespecified propensity score–weighted EC group was derived from a US healthcare claims database. Results: In the RCT, the primary endpoint occurred in 28.6% of OCA (n=168) and 28.9% of placebo patients (n=166; intent-to-treat [ITT] analysis hazard ratio [HR]=1.01, 95% CI=0.68–1.51), but functional unblinding and crossover to commercial therapy occurred, especially in the placebo arm. Correcting for these using inverse probability of censoring weighting (IPCW) and as-treated analyses shifted the HR to favor OCA. In the EC (n=1051), the weighted primary endpoint occurred in 10.1% of OCA and 21.5% of non-OCA patients (HR=0.39; 95% CI=0.22–0.69; P=0.001). No new safety signals were identified in the RCT. Conclusions: Functional unblinding and treatment crossover, particularly in the placebo arm, confounded the ITT estimate of outcomes associated with OCA in the RCT. Comparison with the real-world EC showed that OCA treatment significantly reduced the risk of negative clinical outcomes. These analyses demonstrate the value of EC data in confirmatory trials and suggest that treatment with OCA improves clinical outcomes in patients with PBC
