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Determination of fluphenazine, related phenothiazine drugs and metabolites by combined high-performance liquid chromatography and radioimmunoassay.
Antibodies have been produced in rabbits immunized with a fluphenazine succinate-human serum albumin conjugate. By radioimmunoassay it is possible to quantify fluphenazine (FPZ), related phenothiazine drugs and several of their metabolites at the femtomole level. As little as 370 fmol (160 pg) of FPZ can be detected and up to 0.4 ml of plasma can be added to the incubation mixture (final volume = 1.1 ml). The phenothiazine heterocyclic nucleus is immunodominant and determines the specificity of the antiserum. When a parent drug cross-reacts significantly with antibody, its 7-hydroxide, N-oxide and N-10 side chain altered metabolites can also be determined by the assay. The 8-hydroxide, sulfoxide and 7-hydroxyglucuronide metabolites are not detectable unless present in large amounts. High-performance liquid chromatography was used to separate phenothiazine drugs and metabolites. Since the antiserum has broad specificity, a combined high-performance liquid chromatography and radioimmunoassay procedure permits the identification and quantification of a phenothiazine drug and its serologically reactive metabolites. Patterns of high-performance liquid chromatographic elution and extent of immunologic cross-reaction are characteristic for metabolites relative to the parent drug. This procedure offers distinct advantages in the analysis of this complex family of compounds. FPZ was quantitatively extracted from plasma samples obtained from patients receiving FPZ per os. Although large amounts of serological activity were present in the samples 2 to 6 hr after FPZ ingestion, only 2 to 23% was extractable. The major contributors to the serological activity at times greater than 6 hr were FPZ metabolites. In a preliminary application of the combined techniques, FPZ and a metabolite identified as N-[alpha-(trifluoromethylphenothiazinyl-10)propyl]perazine were quantified in the organic extract of one plasma sample
Metallicities of galaxies in the nearby Lynx-Cancer void
Does the void environment have a sizable effect on the evolution of dwarf
galaxies? If yes, the best probes should be the most fragile least massive
dwarfs. We compiled a sample of about one hundred dwarfs with M_B in the range
-12 to -18 mag, falling within the nearby Lynx-Cancer void. The goal is to
study their evolutionary parameters -- gas metallicity and gas mass-fraction,
and to address the epoch of the first substantial episode of Star Formation.
Here we present and discuss the results of O/H measurements in 38 void
galaxies, among which several the most metal-poor galaxies are found with the
oxygen abundances of 12+log(O/H)=7.12-7.3 dex.Comment: 2 pages, one figure. To appear in proceedings of 'Environment and the
Formation of Galaxies: 30 years later,' (Lisbon, September 2010), published
by Springer-Verla
A slow coronal mass ejection with rising X-ray source
An eruptive event, which occurred on 16th April 2002, is discussed. Using images from the Transition Region and Coronal Explorer ( TRACE) at 195 angstrom, we observe a lifting flux rope which gives rise to a slow coronal mass ejection ( CME). There are supporting velocity observations from the Coronal Diagnostic Spectrometer ( CDS) on the Solar and Heliospheric Observatory ( SOHO), which illustrate the helical nature of the structure. Additionally a rising coronal hard X- ray source, which is observed with the Reuven Ramaty High Energy Solar Spectroscopic Imager ( RHESSI), is shown to follow the flux rope with a speed of similar to 60 km s(-1). It is also sampled by the CDS slit, although it has no signature in the Fe XIX band. Following the passage of this source, there is evidence from the CDS for down- flowing ( cooling) material along newly reconnected loops through Doppler velocity observations, combined with magnetic field modeling. Later, a slow CME is observed with the Large Angle and Spectroscopic Coronagraph ( LASCO). We combine a height- time profile of the flux rope at lower altitudes with the slow CME. The rising flux rope speeds up by a factor of 1.7 at the start of the impulsive energy release and goes through further acceleration before reaching 1.5 solar radii. These observations support classical CME scenarios in which the eruption of a filament precedes flaring activity. Cusped flare loops are observed following the erupting flux rope and their altitude increases with time. In addition we find RHESSI sources both below and above the probable location of the reconnection region
Guidelines for the design of haptic widgets
Haptic feedback has been shown to improve user performance in Graphical User Interface (GUI) targeting tasks in a number of studies. These studies have typically focused on interactions with individual targets, and it is unclear whether the performance increases reported will generalise to the more realistic situation where multiple targets are presented simultaneously. This paper addresses this issue in two ways. Firstly two empirical studies dealing with groups of haptically augmented widgets are presented. These reveal that haptic augmentations of complex widgets can reduce performance, although carefully designed feedback can result in performance improvements. The results of these studies are then used in conjunction with the previous literature to generate general design guidelines for the creation of haptic widgets
Energy and centrality dependences of charged multiplicity density in relativistic nuclear collisions
Using a hadron and string cascade model, JPCIAE, the energy and centrality
dependences of charged particle pseudorapidity density in relativistic nuclear
collisions were studied. Within the framework of this model, both the
relativistic experimental data and the PHOBOS and PHENIX
data at =130 GeV could be reproduced fairly well without retuning
the model parameters. The predictions for full RHIC energy collisions
and for collisions at the ALICE energy were given. Participant nucleon
distributions were calculated based on different methods. It was found that the
number of participant nucleons, for distinguishing various theoretical models.Comment: 10 pages, 4 figures, submitted to Phy. Lett.
Estrogen Binding Protein Activity in Morris Hepatoma 7777 Compared With Normal Rat Liver
Estrogen binding protein activities were determined in the cytosol from adult male Buffalo rat liver and Morris hepatoma 7777. Estrogen receptors were prepared using the protamine sulfate precipitation technique of Chamness. The ability of various unlabeled steroids competing with [3H]estradiol was examined to establish the binding specificity. Estradiol binding in Morris hepatoma 7777 cytosol was greatly decreased compared with that present in hepatic cytosol prepared from normal rat liver. The receptor concentration expressed as femtomoles per milligram of cytoplasmic protein was 31.1 ± 2.9 SD for normal rat liver and 0.41 ± 0.88 SD for the hepatoma. Gel filtration chromatography revealed the presence of an estrogen binder in hepatoma cytosol which was not present in either normal liver or in the protamine sulfate precipitates of hepatoma cytosol. The molecular weight, binding specificity, and precipitation of this protein by specific antiserum suggests that it is α-fetoprotein. © 1984, American Gastroenterological Association. All rights reserved
Local three-nucleon interaction from chiral effective field theory
The three-nucleon (NNN) interaction derived within the chiral effective field
theory at the next-to-next-to-leading order (N2LO) is regulated with a function
depending on the magnitude of the momentum transfer. The regulated NNN
interaction is then local in the coordinate space, which is advantages for some
many-body techniques. Matrix elements of the local chiral NNN interaction are
evaluated in a three-nucleon basis. Using the ab initio no-core shell model
(NCSM) the NNN matrix elements are employed in 3H and 4He bound-state
calculations.Comment: 17 pages, 9 figure
Discovery of the potential role of sensors in a personal emergency response system: what can we learn from a single workshop?
Capturing knowledge from domain experts is important to effectively integrate novel technological support in existing care processes. In this paper, we present our experiences in using a specific type of workshop, which we identified as a decision-tree workshop, to determine the process and information exchange during the usage of a Personal Emergency Response System (PERS). We conducted the workshop with current and possible future users of a PERS system to investigate the potential of context-and social awareness for such a system. We discuss the workshop format as well as the results and reflection on this workshop
Relating near-Earth observations of an interplanetary coronal mass ejection to the conditions at its site of origin in the solar corona
A halo coronal mass ejection (CME) was detected on January 20, 2004. We use solar remote sensing data (SOHO, Culgoora) and near-Earth in situ data (Cluster) to identify the CME source event and show that it was a long duration flare in which a magnetic flux rope was ejected, carrying overlying coronal arcade material along with it. We demonstrate that signatures of both the arcade material and the flux rope material are clearly identifiable in the Cluster and ACE data, indicating that the magnetic field orientations changed little as the material traveled to the Earth, and that the methods we used to infer coronal magnetic field configurations are effective
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