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METABOLISM OF THE A 1 ADENOSINE RECEPTOR POSITRON EMISSION TOMOGRAPHY LIGAND [ 18 F]8-CYCLOPENTYL-3-(3-FLUOROPROPYL)-1-PROPYLXANTHINE ([ 18 F]CPFPX) IN RODENTS AND HUMANS
No full textPositron emission tomography (PET) is a useful procedure for assessing the density The ligand 18 F]CPFPX in primates (Boy et al., 1998) and humans gives rise to at least three polar metabolites in blood, and studies illustrated the confounding effects of these metabolites. For example, the intravenous administration of [ 18 F]CPFPX to experimental animals caused intense labeling of the heart that was unaffected by the administration of unlabeled ligand, evidence for high unspecific binding of a metabolite The physiological importance of the A 1 AR, its wide tissue distribution, and the success of PET-imaging A 1 ARs in the central nervous system urge extension of this technique to other organs. The design of more stable radioligands to achieve that end requires the kind of information about the metabolism of [ 18 F]CPFPX provided by this study. Measurements of receptor density by PET depend on compartmental analysis by mathematical models that are very sensitive to the concentration of native radioligand in blood perfusing the organ (the "input function"). Such measurements on the plasma of human subjects 18 F]CPFPX metabolites in addition to unchanged ligand. Because the radiotracers for PET studies are prepared under no-carrier-added conditions, the amount of compound administered is in the low to subnanomolar range, making direct spectrometric identification of metabolites impossible. As this report describes, incubating CPFPX with human liver microsomes generated compounds that by HPLC had the same mobilities as the metabolites in plasma, and LC-MS tentatively identified them by measuring m/z of the [M ϩ H] ϩ ions. The literature contains little information about the metabolism of synthetic xanthines. The use of CPFPX in humans for diagnostic and research PET imaging necessitates the knowledge of its metabolism in vivo. To our knowledge, the present study of the biotransformation of CPFPX in humans is the first of its kind. Article, publication date, and citation information can be found a
Diets of deep-water pandalid shrimps on the Western Mediterranean slope
No full textAbstract Most of the studies on Mediterranean pandalids focused on their spatial distribution, reproduction patterns and diet but few on interspecific relationships. The present work deals with interspecific comparison between two widely distributed pandalids ( P. martia, P. heterocarpus), analyzing size segregation among three different areas in the northern Aegean Sea. Keywords : Aegean Sea, Decapoda, Crustacea, Population Dynamics, Competition. Logarithmic decline of food energy availability in deep water is the most important factor in shaping of deep water fauna References 1 -Haedrich R.L., 1996. Deep-water fishes: evolution and adaptation in the earth's largest living space
15+ MILLION TOP 1% MOST CITED SCIENTIST 12.2% AUTHORS AND EDITORS FROM TOP 500 UNIVERSITIES 3 A Metaheuristic Approach to Solve the Alternative Subgraphs Assembly Line Balancing Problem
No full textCharacterization of tracks in CR-39 detectors obtained as a result of Pd/D
No full textAbstract. Earlier we reported that the pits generated in CR-39 detectors during Pd/D co-deposition experiments are consistent with those observed for pits that are of a nuclear origin. Spacer experiments and track modeling have been done to characterize the properties of the particles that generated the tracks in the CR-39 detectors. The effect of water on the energetics of the particles and their resultant tracks is discussed
PRINCETON PLASMA PHYSICS LABORATORY PRINCETON UNIVERSITY, PRINCETON, NEW JERSEY Simulation of Optical and Synthetic Imaging using Microwave Reflectometry Availability Simulation of optical and synthetic imaging using microwave reflectometry
No full textAbstract. 2-D full-wave time-dependent simulations in full plasma geometry are presented which show that conventional reflectometry (without a lens) can be used to synthetically image density fluctuations in fusion plasmas under conditions where the parallel correlation length greatly exceeds the poloidal correlation length of the turbulence. The advantage of synthetic imaging is that the image can be produced without the need for a large lens of high optical quality, and each frequency that is launched can be independently imaged. A particularly simple arrangement, consisting of a single receiver located at the midpoint of a microwave beam propagating along the plasma midplane is shown to suffice for imaging purposes. However, as the ratio of the parallel to poloidal correlation length decreases, a poloidal array of receivers needs to be used to synthesize the image with high accuracy. Simulations using DIII-D relevant parameters show the similarity of synthetic and optical imaging in present day experiments
A study incorporating nano-sized silica into PVC-blend-based polymer electrolytes for lithium batteries
No full textAbstract Blends of poly(vinyl chloride)-poly(methyl methacrylate) (PVC/PMMA) and poly(vinyl chloride)-poly (ethylene oxide) (PVC/PEO) with lithium triflate (LiCF 3 SO 3 ) as salt, ethylene carbonate (EC), and dibuthyl phthalate (DBP) as plasticizers and nano-sized silica (SiO 2 ) as filler, the first of its kind in such a study, were prepared using the solution-cast technique. This study affirmed that SiO 2 added PVC-PMMA and PVC-PEO-blend-based polymer electrolytes have the ability to retain their ionic conductivity and integrity even after 60 days of storage time at room temperature. The reduction of ionic conductivity values in PVC-PMMA-LiCF 3 SO 3 -DBP-EC:SiO 2 -based and SiO 2 -free membranes are 9 and 30%, respectively. When PVC-PEO-blend was used, the reduction of ionic conductivity values in PVC-PEO-LiCF 3 SO 3 -DBP-EC:SiO 2 -based and SiO 2 -free system was 16 and 40%, respectively, after 60 days of storage also at room temperature. The SiO 2 -based complexes were also found to maintain their conductivity at higher temperatures of 60°C and 90°C with progressive storage times. This clearly shows that the SiO 2 -induced stabilizing effect is maintained even at higher temperatures. Silica has brought the conductivity of polymer electrolytes into the useful realm for materials in lithium polymer battery applications
The non-linear response of molecular junctions: the polaron model revisited
No full textAbstract A polaron model proposed as a possible mechanism for non-linear conductance (Galperin et al 2005 Nano Lett. 5 125-30) is revisited with the focus on the differences between the weak and strong molecule-lead coupling cases. Within the one-molecule-level model we present an approximate expression for the electronic Green function corresponding to the inelastic transport case, which in the appropriate limits reduces to expressions presented previously for the isolated molecule and for a molecular junction coupled to a slow vibration (static limit). The relevance of considerations based on the isolated molecule limit to understanding properties of molecular junctions is discussed
