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21.
Seshulatha Jamalapuram Pradeep Kumar Vuppala Ahmed H. Abdelazeem Christopher R. McCurdy Bonnie A. Avery 《Biomedical chromatography : BMC》2013,27(8):1034-1040
Methamphetamine abuse continues as a major problem in the USA owing to its powerful psychological addictive properties. AZ66, 3‐[4‐(4‐cyclohexylpiperazine‐1‐yl)pentyl]‐6‐fluorobenzo[d]thiazole‐2(3H)‐one, an optimized sigma receptor ligand, is a promising therapeutic agent against methamphetamine. To study the in vivo pharmacokinetics of this novel sigma receptor ligand in rats, a sensitive ultra‐performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method was developed in rat plasma and validated. The developed method requires a small volume of plasma (100 μL) and a simple liquid–liquid extraction. The chromatographic separations were achieved in 3.3 min using an Acquity UPLC BEH Shield RP18 column. The mass spectrophotometric detection was carried out using a Waters Micromass Quattro MicroTM triple‐quadrupole system. Multiple reaction monitoring was used for the quantitation with transitions m/z 406 → m/z 181 for AZ66 and m/z 448 → m/z 285 for aripiprazole. The method was validated over a concentration range of 1–3500 ng/mL and the lower limit of quantitation was determined to be 1 ng/mL. Validation of the assay demonstrated that the developed UPLC/MS/MS method was sensitive, accurate and selective for the determination of AZ66 in rat plasma. The present method has been successfully applied to an i.v. pharmacokinetic study in Sprague–Dawley rats. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
22.
Rei Matsuzaki Shigeko Asai C. William McCurdy Satoshi Yabushita 《Theoretical chemistry accounts》2014,133(9):1-12
The goals of electronic structure theory are to make quantitative predictions of molecular properties and to provide qualitative insight into bonding as well as features of potential energy surfaces. Oftentimes, the two goals are at odds as an accurate treatment requires a complicated wave function that obscures chemical insight. The multifacet graphically contracted function (MFGCF) method offers a new approach that allows both goals to be addressed simultaneously. The recursive product structure of the MFGCF wave function reduces the exponential scaling of the exact wave function and allows the computation of molecular properties with polynomial scaling with respect to system size. Additionally, the graph density concept provides an intuitive tool for visualizing and analyzing the qualitative features of the wave function. In this work, the graph densities for model systems are examined to demonstrate their utility in analyzing the changes in wave function character along potential energy surfaces and near avoided crossings. Finally, we demonstrate that the graph density exposes the structure of the exact wave function for a system of noninteracting molecules as a product of the fragment wave functions. 相似文献
23.
A light-controlled reversible binding switch based on photochromic 3H-naphtho[2,1-b]pyran is under development for studying cellular oscillatory calcium signals. The binding affinities of the closed and open forms of substituted naphthopyran 1 for Ca(2+), Mg(2+), and Sr(2+) in buffer were determined. The photochemically ring-opened form of the receptor exhibited increased affinity compared to the thermally stable closed form of the receptor. The binding affinity difference for Ca(2+) was approximately 77-fold at pH 7.6. 相似文献
24.
In this article, we derive the intrinsic equations for a generalized relaxed elastic line on an oriented surface in the Galilean 3-dimensional space G3. These equations will give direct and more geometric approach to questions concerning about generalized relaxed elastic lines on an oriented surface in G3. 相似文献
25.
Lenneke WA van Hooijdonk Muhammad Ichwan Thomas F Dijkmans Theo G Schouten Marijke WA de Backer Roger AH Adan Fons J Verbeek Erno Vreugdenhil Carlos P Fitzsimons 《BMC neuroscience》2009,10(1):2-19
Background
In the adult hippocampus, the granule cell layer of the dentate gyrus is a heterogeneous structure formed by neurons of different ages, morphologies and electrophysiological properties. Retroviral vectors have been extensively used to transduce cells of the granule cell layer and study their inherent properties in an intact brain environment. In addition, lentivirus-based vectors have been used to deliver transgenes to replicative and non-replicative cells as well, such as post mitotic neurons of the CNS. However, only few studies have been dedicated to address the applicability of these widespread used vectors to hippocampal cells in vivo. Therefore, the aim of this study was to extensively characterize the cell types that are effectively transduced in vivo by VSVg-pseudotyped lentivirus-based vectors in the hippocampus dentate gyrus. 相似文献26.
Prem Paul Singh Keith G. McCurdy Earl M. Woolley Loren G. Hepler 《Journal of solution chemistry》1977,6(5):327-330
We have used a Picker flow calorimeter for measurements leading to apparent molal heat capacities of dilute aqueous solutions of HClO4 and NaClO4 at 298°K. Results have been used to derive
c
°
=–27.1J-°K
–1-mole
–1 for HClO4 (aq.),
c
°
=15.2J-°K
–1-mole
–1 for NaClO4 (aq.), and C
p=–213.8J-°K–1-mole–1 for ionization of water. 相似文献
27.
28.
McCurdy A.H. Plewa J.S. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1992,20(3):139-148
An analysis is made of temporal evolution of electromagnetic modes in a two-mode gyrotron oscillator characterized by phase and amplitude interaction through the terms linear in the oscillator power. The problem is solved in the context of amplitudes and phases which vary slowly compared with the period of oscillation. Specific reference is made to competition between TE11q modes in a closed cavity gyrotron. Qualitative features which are found include phase locking, beat frequencies, periodic pulling, and mode excitation. This work has applicability when the frequency separation between the modes is on the order of the frequency bandwidth of each mode, or the modes are equally spaced in frequency. Gyrotrons of this type include those with low-quality-factor modes or degenerate modes. Phase interaction in the case of equally spaced cavity modes is of importance in analyzing mode-locking phenomena 相似文献
29.
D. E. McCurdy L. E. Kuruvilla L. E. Fiske Ch. J. Bianconi 《Journal of Radioanalytical and Nuclear Chemistry》1998,233(1-2):29-37
Site remediation projects dealing with uranium, thorium or radium require the services of a radioassay laboratory during the
site characterization, remediation and final site survey/verification phases. In the U.S., regulatory agencies and industry
guidelines recommend that the remediation contractor conduct an external laboratory QC program to ensure the quality of the
analytical results. The commercial availability of certified natural soil matrices is extremely limited not only by nuclide
and nuclide concentration but also by soil type. In most cases, the applicability of these materials for an external QC program
is questionable since the chemical constituents of the certified soil may not be representative of the remediation soil type.
Also, such materials are typically only suitable as single blind performance evaluation (PE) samples. The Yankee Atomic Environmental
Laboratory (YAEL) has characterized soil materials from several uranium mining and milling sites for use in two laboratory
PE programs. The site specific PE materials were prepared in accordance with their intended use and quality performance requirements.
One PE material was dried, pulverized to a particle size of approximately 10 microns and homogeneously blended. The second
PE material (total of 1,024 kg) was methodically field blended and aliquoted to produce 1,000 separate homogeneous 1 kg samples.
Both PE materials were characterized for radionuclide concentration and heterogeneity or sample distribution. A summary of
the characterization studies of the different PE materials as well as the quality performance criteria developed for evaluating
the laboratory's performance and the advantages and disadvantages of using each PE material will be discussed and summarized. 相似文献
30.
The equations of magnetostatic equilibria for a plasma in agravitational field are investigated analytically. For equilibriawith an ignorable spatial coordinate, the equations reduce toa single nonlinear elliptic equation for the magnetic potentialu known as the Grad-Shafranov equation. By specifying the arbitraryfunctions in this equation, a Liouville equation is obtained.Bäcklund transformations are described and applied to obtainexact solutions for the Liouville equation modelling an isothermalmagnetostatic atmosphere, in which the current density J isproportional to the exponential of the magnetic potential andmoveover falls off exponentially with distance vertical to thebase with an e-folding distance equal to the gravitational scaleheight. 相似文献