Rhône-Poulenc

About: Rhône-Poulenc is a based out in . It is known for research contribution in the topics: Alkyl & Catalysis. The organization has 8909 authors who have published 8934 publications receiving 182241 citations. The organization is also known as: Rhone-Poulenc.

Imprinted gene in postnatal growth role

Abstract: Mice that have been specially bred to lack a protein known as Grf-1, which is normally found only in the brain, do not grow properly after they are born and remain small all their lives. We have now identified a function of Grf-1 as an important regulator of the synthesis and release of growth hormone. Moreover, grf1, the gene encoding this protein, is unlike other imprinted genes that affect growth because it operates after, rather than before, birth.

Rheology of a Magnetorheological Fluid

Abstract: We report on experimental investigations of the rheological behavior of aqueous magnetic suspensions. The suspended particles are monodisperse colloidal polystyrene spheres which contain magnetic Fe203-grains. In the absence of a magnetic field these suspensions behave as Newtonian fluids, whereas under the influence of a magnetic field due to the formation of an ordered structure the apparent viscosity of the suspension increases up to three orders of magnitude and they clearly exhibit non-Newtonian properties, such as shear thinning and yield stress. The apparent viscosity depends on the magnetic field according to aq - H2". Increasing the volume fraction of the particles in the range of 0.014 < 0 < 0.12 results in a linear increase in apparent viscosity and yield stress. Both apparent viscosity and yield stress depend also on the particle size as first measurements on particles with diameters ranging from 0.5 Am to 1.0,Am clearly show. All measurements were carried out with a rotation viscometer using ...

Restenosis following angioplasty in the swine coronary artery is inhibited by an orally active PDGF-receptor tyrosine kinase inhibitor, RPR101511A.

Abstract: Background—Platelet-derived growth factor (PDGF), a purported mediator of arterial response to injury, stimulates proliferation, chemotaxis, and matrix production by activation of its membrane receptor tyrosine kinase. Because these activities underlie restenosis, inhibition of the PDGF-receptor tyrosine kinase (PDGFr-TK) is postulated to decrease restenosis. Methods and Results—RPR101511A is a novel compound which selectively and potently inhibits the cell-free and in situ PDGFr-TK and PDGFr-dependent proliferation and chemotaxis in vascular smooth muscle cells (VSMC). To evaluate the effect of RPR101511A (30 mg · kg−1 · d−1 BID for 28 days following PTCA) on coronary restenosis, PTCA was performed in hypercholesterolemic minipigs whose left anterior descending (LAD) coronary artery had been injured by overdilation and denudation, yielding a previously existing lesion. Angiographically determined prePTCA minimal lumen diameters (MLD) were similar in vehicle and RPR101511A-treated pigs (1.98±0.09 versus 2...

Simultaneous control of particulate and NOx emissions from diesel engines

Abstract: In view of increased concerns regarding the effects of diesel engine particulate and NO x emissions on human health and the environment, legislators are currently reviewing and proposing legislation targeting the reduction of these pollutants. The reported serious health risks of particulate matter on the respiratory system and its carcinogenic effects, along with the known contributions of NO x in acid rain and ground ozone formation, demand that the enacted legislation reflect in severity the health and environmental threats. As a consequence, diesel engine manufacturers and users are under increasing pressure to greatly reduce the engine's exhaust emissions. A system which is currently being proposed for the simultaneous control of diesel particulate matter and NO x emissions involves the use of a cerium fuel-borne catalyst/filter/EGR system. This paper describes the principles of operation of Rhoˆne-Poulenc's cerium fuel-borne catalyst and the factors that govern its use.