Transport of chromium(VI) through a Cyanex 921‐supported liquid membrane from HCl solutions

The transport of chromium(VI) through a flat‐sheet supported liquid membrane containing Cyanex 921 as a carrier has been investigated. The permeation of the metal is investigated as a function of various experimental variables: hydrodynamic conditions, concentration of chromium(VI) and HCl in the feed phase, carrier concentration and diluent in the membrane and strippant concentration in the stripping phase. The mass transfer coefficient and the thickness of the aqueous boundary layer were calculated from the experimental data. Furthermore, the selectivity of Cyanex 921‐based flat‐sheet supported liquid membrane towards different metal ions and the behaviour of the system against other carriers are presented. Copyright © 2003 Society of Chemical Industry     

Electrophysiologic and electrocardiographic aspects of the transplanted heart

The authors suggest that academic institutions build business-oriented policies and practices into the development of any nurse-run clinic to set the stage for financial independence when special or development funding ends. One university-affiliated program that provides 4,000 to 5,000 annual visits drastically changed its strategies when threatened with closure after free rent and other subsidies were withdrawn. The growing emphasis on ambulatory care roles for nurses at all levels makes such clinics critical to the success of the broad-based curricula of nursing education programs, as well as the clinic's value to communities they serve. Funding difficulties frequently threaten the existence of such nurse-run clinics once the initial grant funding is no longer available. This has caused a new emphasis on running such clinics in a business-wise manner. Among the strategies initiated were: direct full-pay at the time of service; a realistic business management plan; aggressive planned marketing; contracts and agreements with other agencies; obtaining provider status with selected HMOs.     

Maximum power density for an endoreversible carnot heat engine

An analysis using maximum power-density criteria has been carried out for an endoreversible Carnot heat engine. The results have been compared with known results on maximum power analysis. The design parameters at maximum power density lead to smaller and more efficient endoreversible Carnot heat engines than those working at maximum power output.     

Determining the core of journals of a research centre: The example of researchers from the Department of Rural Economy and Sociology of the Institut National de la Recherche Agronomique,France

This paper analyses the determination of visibility of journals in which researchers of INRA (National Institute for Agricultural Research) publish. The corpus is comprised of 671 articles published over a period of four years in 258 journals. The advantage of the method applied for determining the visibility of journals is that it combines two approaches: a) bibliometric indicators (coverage by the ISI-publications and by two specific French databases) and b) experts' opinions (10 economists and sociologists). The main results are: a) There is a convergence between the opinion of the experts and «visibility» in the databases, b) The impact factor confirms the main opinions of the experts. The first journals ranked by the experts and JCR Social Sciences are the same but represent only 40 per cent of the total journals analysed. The other journals were revealed by the experts and French databases.«Whoever seeks to pass a balanced but lucid judgement on the general trends of the activity carried out by the profession to which he belongs, is liable to say either banalities or to hurt his colleagues»The notion which we retain of core is that which is successively and conjointly validated by the experts and by the major databases representative of the field.This study was financed by the Department of Rural Economy and Sociology of INRA.     

MRI of intramedullary sarcoidosis: follow-up of a case

Significative enhancement of free radical formation (FRO) in vivo is an important feature of hypertensive disorders of pregnancy (HDP), namely preeclampsia (PIH). The latest investigations about the pathology of HDP, showed the contribution of placental circulation to the development and evolution of such disease. The placental bed can be a potential source of FRO or activation of cells that can produce FRO. Glutathione, is an important molecule for cellular protection against damage, is a cofactor of many enzymes, in particular, for the glutathione peroxidase of the placental tissue; this enzyme in the placenta bed prevent the production of thromboxan and lipoperoxides; the latter are potentially damaging to the endothelium cells and can cause vasoconstriction, the most important feature of PIH. The activity of that enzyme is deficient in PIH. We studied, by fluorometric assay, the concentrations of the two states of glutathione in placental homogenates (PLH) from pregnant women without pathology (PWN) and from pregnant women with PIH (PWPIH). The data showed significant low concentrations in the PLH of the two states of glutathione in the PWN against high concentrations of this molecule in the PLH from PWPIH. This feature can result from a deficient user of the glutathione by the cellular mechanism for prevention against oxidative factors. In addition, our study shows a biochemical marker that is suggestive that the placental bed is a potential source of FRO production in PIH.     

Growth structure investigation of MgF2 and NdF3 films grown by molecular beam deposition on CaF2(111) substrates

The growth structure of MgF₂ and NdF₃ films grown on polished CaF₂(111) substrates deposited by molecular beam deposition has been investigated using transmission electron microscopy (TEM) of microfractographical and surface replications as well as cross-sectional TEM, atomic force microscopy, packing density, and absorption measurements. It has been shown that by taking advantage of ultrahigh vacuum environments and a special stratification property of MgF₂ and NdF₃ films, the preparation of nanocrystalline films of high packing density and low optical absorption is possible at a substrate temperature of 425 K.