cssi/SciSciGPT-SciSciNet huggingface dataset:
Advanced Thermal Storage Fluids for Solar Parabolic Trough Systems

It has been established that the development of a storage option and increasing the operating temperature for parabolic trough electric systems can significantly reduce the levelized electricity cost (LEC) compared to the current state of the art. Both improvements require a new heat transfer fluid that must have a very low vapor pressure at the hot operating temperature and combined with a high thermal stability, higher than 450°C. Further, the piping layout of trough plants dictates that the fluid not be allowed to freeze, which dictates the use of extensive insulation and heat tracing unless the fluid has a freezing point near 0°C. At present, it seems likely that this “ideal” fluid will have to be found among organic rather than inorganic salts. We are therefore investigating the chemical and thermal properties of ‘room temperature ionic liquids’ (RTILs) that hold much promise as a new class of heat transfer or storage fluids.© 2002 ASME
Current methodological refinements for the acquisition of life history information in fishes: paradigms from pan-oceanic billfishes.

Abstract 1. 1. Many factors contribute to hinder progress in estimating and verifying age, growth, and life history strategies of billfishes. It is necessary to discern growth of an individual fish to circumvent problems in substantiating age, growth, longevity and age at maturity. These biological characteristics allow us to discover what life history periods are critical to survival and reproduction. 2. 2. Two theoretical approaches may be considered for studying the age of billfish: Age may be delineated in terms of the passage of time (chronological age), or may be examined as the progression of physiological development (physiological age). 3. 3. Hard tissues such as otoliths, spines, vertebrae and post-mitotic tissues contain a plethora of biological and ecological information documenting a fish's chronological and physiological age and individual life history. In calcified tissues, this information can be obtained when the proper techniques are used to investigate the structural and chemical components of billfish hard parts. Chemical analyses of stable isotopes and elemental concentrations in calcified tissues suggest that calcified tissues contain hydrographie, nutritional and migrational information—life history information. 4. 4. Utilization of structural and chemical analyses of billfish otoliths, vertebrae, and other hard parts, enables specific phases of growth to be linked to enrivonmental occurrences. Measurement of the metabolically accumulated cellular pigment, lipofuscin, in post-mitotic tissue may make it possible to define physiological age or readiness. Internal and external structural and chemical analyses of otoliths, vertebrae, and other hard parts, combined with biochemical assays of post-mitotic tissue will greatly enhance studies of life history. The methods presented provide insights into means by which life history knowledge can be obtained.
Carrier density distribution in modulation doped GaAs-AlxGa1−xAs quantum well heterostructures

Abstract A theoretical model for the distribution of charged carriers at the interface of a doped Al x Ga 1− x As-undoped GaAs heterostructure is evaluated. Assuming a triangular potential well at the interface, we obtain numerically, curves describing the Fermi energy, depletion width in the alloy, and average separation of impurities and carriers, and the electron density at the interface as functions of alloy layer composition and doping level. The results obtained can be applied to multiple heterointerface quantum well heterostructures and superlattices as well. Carrie concentration profile data on a 51-layer modulation doped QWH grown by MOCVD are presented and are discussed using the results of the model.
Escape from HER-family tyrosine kinase inhibitor therapy by the kinase-inactive HER3.

Certain tyrosine kinases are overactive in many cancers, and drugs that inhibit them, such as the leukaemia treatment imatinib, can be successful. But they don't work for all tyrosine kinase-driven cancers, and new work points to a possible reason why. The kinase HER2 is frequently overactive in breast cancers and signals through another family member, HER3. Sergina et al. find that when HER2 is partially blocked by kinase inhibitors, a feedback mechanism causes an increase of active HER3 at the plasma membrane where it continues to signal cancer cell proliferation. So more effective inhibitors that block HER2 completely, and reduce HER3 activity too, may be more effective cancer therapies. Oncogenic tyrosine kinases have proved to be promising targets for the development of highly effective anticancer drugs. However, tyrosine kinase inhibitors (TKIs) against the human epidermal growth factor receptor (HER) family show only limited activity against HER2-driven breast cancers, despite effective inhibition of epidermal growth factor receptor (EGFR) and HER2 in vivo1,2,3,4,5,6,7,8. The reasons for this are unclear. Signalling in trans is a key feature of this multimember family and the critically important phosphatidylinositol-3-OH kinase (PI(3)K)/Akt pathway is driven predominantly through transphosphorylation of the kinase-inactive HER3 (refs 9, 10). Here we show that HER3 and consequently PI(3)K/Akt signalling evade inhibition by current HER-family TKIs in vitro and in tumours in vivo. This is due to a compensatory shift in the HER3 phosphorylation–dephosphorylation equilibrium, driven by increased membrane HER3 expression driving the phosphorylation reaction and by reduced HER3 phosphatase activity impeding the dephosphorylation reaction. These compensatory changes are driven by Akt-mediated negative-feedback signalling. Although HER3 is not a direct target of TKIs, HER3 substrate resistance undermines their efficacy and has thus far gone undetected. The experimental abrogation of HER3 resistance by small interfering RNA knockdown restores potent pro-apoptotic activity to otherwise cytostatic HER TKIs, re-affirming the oncogene-addicted nature of HER2-driven tumours and the therapeutic promise of this oncoprotein target. However, because HER3 signalling is buffered against an incomplete inhibition of HER2 kinase, much more potent TKIs or combination strategies are required to silence oncogenic HER2 signalling effectively. The biologic marker with which to assess the efficacy of HER TKIs should be the transphosphorylation of HER3 rather than autophosphorylation.
Use of Artificial Stomach−Duodenum Model for Investigation of Dosing Fluid Effect on Clinical Trial Variability

Lilly Compound X (LCX) is an oncology drug that was tested in a phase I clinical study using starch blend capsules. The drug was given to a small patient population (4 patients) and showed large inter- and intra-patient variability. In order to evaluate the possible effect of stomach pH on exposure and ways to mitigate the variability issue, artificial stomach-duodenum (ASD) experiments were conducted to investigate the hypothesis that carefully selected dosing fluids would have an impact in minimizing exposure variability caused by the formulation, which could lead to more consistent evaluation of drug absorption in patients. The ASD data corroborates the observed variability, and was a good tool to investigate the effect of stomach pH and potential dosing solutions on duodenal concentrations. Administering capsules co-formulated with Captisol (10% drug load) along with Sprite was shown by the ASD to be an effective way to increase duodenal concentrations as well as to reduce the difference between duodenal concentrations for different gastric pH. The reduction in variability of duodenum AUC (in ASD) is expected to correlate well with a reduction of variability in patient exposure. The dosing regimen of Sprite/Captisol is therefore suggested for future clinical trials involving LCX. Furthermore, for design of early phase clinical trials, ASD technology can be used to assist in choosing the proper dosing solution to mitigate absorption and exposure variability issues.
Limitations of Series-Fed Arrays in Broadband Communications

The purpose of this paper is to investigate the signal distortion which results when long, series-fed arrays are used for communication. It is shown that under certain conditions the antenna array can be considered a linear filter, the response of which is a function of frequency as well as spatial coordinates. The distortion accompanying the transmission as measured by the least mean-square difference between the transmitted and the received signals is derived. This expression is evaluated for the case of a uniformly excited array and a rectangular band-pass signal spectrum. In the absence of noise the transmitted signal can be completely recovered in the receiver by employing the proper linear filter. In the presence of noise the signal cannot, of course, be completely recovered. However, a technique for minimizing the distortion, in this case using a pre-filter and a post-filter, is investigated.
The Effect of Stress-Dependent Permeability on Gas Production and Well Testing

The effect of stress-dependent permeability on gas production and well testing in tight gas sands was studied by use of a modified pseudopressure that included stress dependence. This work assumes that information on cores is applicable to reservoir behavior. Because microcracks are the primary path for flow through tight-gas sand cores, average stress-dependent permeabilities were found as an average over all crack orientations in a nonuniform stress field, with a horizontal stress only 0.6 times the vertical one. Initial in-situ permeabilities are found to be two to five times the values obtained from uniformly restressed cores. Stress dependence decreases initial gas production by at most 30%, with the loss increasing over reservoir depletion. Buildup tests yield reliable results for the properties at average reservoir pressure. Drawdown tests are more sensitive to stress effects and are much less reliable.
A CPA preparation program for non-accounting majors

Abstract The CPA Preparation Program is an innovative program in accounting education designed to prepare non-accounting majors for CPA certification. The program consists of the required courses necessary to sit for the CPA exam.
Al/Cu2O thermite compatibility studies by x-ray photoelectron and x-ray induced auger spectroscopy

Abstract The surface chemistry of Al/Cu 2 O thermite in powdered mixtures and in pressed pellets was studied before and after accelerated agings with x-ray ph The Al 2 O 3 film thicknesses on Al metal surfaces were deduced from signal intensity ratios of Al +3 and Al in XPS of Al 2s and from Al K-LL X Stearic acid, the organic additive to Al powders, was detected by the C 1s signal. The CuO impurity in Cu 2 O was observed in the Cu 2p 3 2 signal which was broadened by unpaired electron spin-spin interaction in the Cu +2 d 9 orbital; both impurities were removed du
The multiple roles of N.L. Gage in the creation of educational effectiveness fields

Abstract One measure of a scholar's contributions to his field is the extent to which his work has impact beyond his area or original focus. The authors’ examine N.L. Gage's impact in the area of school effects research. The first of Gage's impacts has been in arguing for a pragmatic orientation to the building of a scientific base for the study of education. The second has been in both leading and supporting studies that focused on direct observation of classroom teaching processes, and linking those processes to measurable outcomes. Four examples of the impacts of Gage's work are presented and discussed. The school effects field would not have made as much progress had not the teacher effects field generally, and the work of N.L. Gage in particular, preceded it.
Theory of gel electrophoresis of DNA.

A theory of the electrophoresis of DNA through gels with large interfiber spacing, such as dilute agarose, is presented. We assume that the DNA molecule moves along its axis through a “tube” in a neutral gel under the influence of the electric field. The tube is random except for possible bias due to the effects of the field. When the field is small, we easily recover the inverse-length dependence of the mobility found previously by de Gennes and by Doi and Edwards. At higher fields, a new effect appears; the tube becomes oriented because the field biases the direction of the leading end of the chain as it moves to form an extension of the tube. This leads to an increase of the mobility with increasing field by adding a field-dependent but length-independent term to the mobility expression. In agreement with experiment, we find that the field effect can be important at fields as low as 1 V/cm and that the effect can seriously decrease the sensitivity of the mobility to chain length. We also examine the fluctuation of the migration distance, the degree of orientation induced by the field, and the transient effects occurring when the feld direction is rotated by a right angle.
Direct measurement of the percolation probability in carbon nanofiber-polyimide nanocomposites.

We present the first experimental measurement of the geometric critical exponent $\ensuremath{\beta}$ associated with the percolation probability, the probability a metallic filler belongs to the conducting network, of an electrical composite. The technique employs conducting-tip atomic force microscopy to obtain a conducting areal density, and is demonstrated on polyimide nanocomposites containing different concentrations of carbon nanofibers. We find $\ensuremath{\beta}\ensuremath{\approx}1$ and $t$ (the exponent for bulk conductivity) $\ensuremath{\approx}3$. These values are consistent with the predictions for the Bethe lattice and larger than the values predicted in the 3D lattice percolation model. Hence, this electrical composite likely belongs to the same universality class as the Bethe lattice. The ability to measure geometric and transport critical exponents on the same material is critical to drawing this conclusion.
Dipyridamole thallium-201 imaging versus dobutamine echocardiography for the evaluation of coronary artery disease in patients unable to exercise

Abstract The present study used 51 patients in a prospective, crossover, blinded comparison of dipyridamole thallium-201 imaging and dobutamine echocardiography for (1) detection of coronary artery disease (CAD), (2) detection of inducible ischemia, and (3) determination of myocardial viability. The detection of CAD was based on quantitative defects on initial planar thallium-201 images and resting or inducible wall motion abnormalities on echocardiography. Detection of ischemia was based on redistribution on delayed thallium-201 images and inducible wall motion abnormality on echocardiography. The myocardium in a region with resting wall motion abnormality was considered viable if it showed either redistribution or >50% activity on delayed thallium-201 images, and if regional function either improved or worsened on echocardiography. The tests were comparable for the detection of CAD (53 and 59%, respectively, p = 0.23). Thallium-201 was superior to echocardiography for the detection of ischemia (35 vs 14%, respectively, p = 0.01). Although the incidence of viable myocardium was equivalent by the 2 tests (100 and 96%, respectively, p = 0.99) for each abnormally moving segment in the 24 patients with resting wall motion abnormality on echocardiography, it was greater on thallium-201 imaging (98 vs 68%, p It is concluded that because of its better ability to detect inducible myocardial ischemia and determine viability in myocardial segments showing reduced function, dipyridamole thallium-201 imaging appears to be superior to dobutamine echocardiography for the evaluation of CAD in patients unable to exercise.
Estrogen alters the responsiveness of the anterior pituitary gland to the actions of dopamine on lysosomal enzyme activity and prolactin release.

The effects of dopamine on PRL secretion and lysosomal enzyme activity in anterior pituitary tissue from rats selected during various stages of the estrous cycle were examined under in vitro conditions. During the estrous cycle, there was a marked variation in the capacity of dopamine to stimulate the activity of the lysosomal enzyme β-glucuronidase in the anterior pituitary gland. Moreover, this variation in the responsiveness of pituitary tissue to the stimulatory action of dopamine on β-glucuronidase activity was accompanied by a similar variation in the responsiveness of the tissue to the inhibitory action of dopamine on PRL release. Anterior pituitary glands from diestrous rats were the most sensitive to the actions of dopamine on β-glucuronidase activity and PRL release, whereas glands from estrous animals were the least sensitive. Ovariectomy on the day of diestrus prevented the decline in the responsiveness of the anterior lobe to the actions of dopamine normally seen 2 days later (on the presumpt...
Cadherin-11 contributes to pulmonary fibrosis: potential role in TGF-β production and epithelial to mesenchymal transition

Pulmonary fibrosis, characterized by excess deposition of extracellular matrix by myofibroblasts, is a serious component of chronic lung diseases. Cadherin-11 (CDH11) is increased in wound healing and fibrotic skin. We hypothesized that CDH11 is increased in pulmonary fibrosis and contributes its development. CDH11 expression was assessed in lung tissue from idiopathic pulmonary fibrosis patients. The role of CDH11 in lung fibrosis was determined using the bleomycin model of pulmonary fibrosis, and in vitro analyses were performed on A549 cells during the process of epithelial to mesenchymal transition (EMT). Immunohistochemical studies demonstrated CDH11 expression on fibroblasts, epithelial cells, and alveolar macrophages of patients with pulmonary fibrosis and mice given bleomycin. Interestingly, CDH11-deficient mice had decreased fibrotic endpoints in the bleomycin model of pulmonary fibrosis compared to wild-type mice. Furthermore, anti-CDH11-neutralizing monoclonal antibodies successfully treated established pulmonary fibrosis induced by bleomycin. TGF-β levels were reduced in bronchoalveolar lavage (BAL) fluid, BAL cells, and primary alveolar macrophages from CDH11-deficient mice. Mechanistic studies demonstrated that TGF-β up-regulated CDH11 expression on A549 cells, and inhibition of CDH11 expression using siRNA reduced TGF-β-induced EMT. Together, these results identify CDH11 as a novel therapeutic target for pulmonary fibrosis. Schneider, D. J., Wu, M., Le, T. T., Cho, S.-H., Brenner, M. B., Blackburn, M. R., Agarwal, S. K. Cadherin-11 contributes to pulmonary fibrosis: potential role in TGFβ production and epithelial to mesenchymal transition.
Indiana Lane Merge System for Work Zones on Rural Freeways

The Indiana Department of Transportation and Purdue University have been investigating and implementing a novel traffic control system at two-lane freeway work zone entries to reduce the number of aggressive lane changes close to the lane taper. The system creates a variable no passing zone through a series of dynamic "DO NOT PASS" signs activated in response to congestion detected on the continuous lane. The Purdue team investigated the operational effect of the system to develop preliminary guidelines for system deployment. The research results indicate that the system improves drivers' behavior toward more safety and reduces travel time in the continuous lane. The simulation model developed at Purdue was used to generate data and formulate rules for system deployment. Language: en
Regulator of G-protein signalling expression and function in ovarian cancer cell lines

Regulator of G-protein signalling (RGS)2 proteins critically regulate signalling cascades initiated by G-protein coupled receptors (GPCRs) by accelerating the deactivation of heterotrimeric G-proteins. Lysophosphatidic acid (LPA) is the predominant growth factor that drives the progression of ovarian cancer by activating specific GPCRs and G-proteins expressed in ovarian cancer cells. We have recently reported that RGS proteins endogenously expressed in SKOV-3 ovarian cancer cells dramatically attenuate LPA stimulated cell signalling. The goal of this study was twofold: first, to identify candidate RGS proteins expressed in SKOV-3 cells that may account for the reported negative regulation of G-protein signalling, and second, to determine if these RGS protein transcripts are differentially expressed among commonly utilized ovarian cancer cell lines and non-cancerous ovarian cell lines. Reverse transcriptase-PCR was performed to determine transcript expression of 22 major RGS subtypes in RNA isolated from SKOV-3, OVCAR-3 and Caov-3 ovarian cancer cell lines and non-cancerous immortalized ovarian surface epithelial (IOSE) cells. Fifteen RGS transcripts were detected in SKOV-3 cell lines. To compare the relative expression levels in these cell lines, quantitative real time RT-PCR was performed on select transcripts. RGS19/GAIP was expressed at similar levels in all four cell lines, while RGS2 transcript was detected at levels slightly lower in ovarian cancer cells as compared to IOSE cells. RGS4 and RGS6 transcripts were expressed at dramatically different levels in ovarian cancer cell lines as compared to IOSE cells. RGS4 transcript was detected in IOSE at levels several thousand fold higher than its expression level in ovarian cancer cells lines, while RGS6 transcript was expressed fivefold higher in SKOV-3 cells as compared to IOSE cells, and over a thousand fold higher in OVCAR-3 and Caov-3 cells as compared to IOSE cells. Functional studies of RGS 2, 6, and 19/GAIP were performed by measuring their effects on LPA stimulated production of inositol phosphates. In COS-7 cells expressing individual exogenous LPA receptors, RGS2 and RSG19/GAIP attenuated signalling initiated by LPA1, LPA2, or LPA3, while RGS6 only inhibited signalling initiated by LPA2 receptors. In SKOV-3 ovarian cancer cells, RGS2 but not RGS6 or RGS19/GAIP, inhibited LPA stimulated inositol phosphate production. In contrast, in CAOV-3 cells RGS19/GAIP strongly attenuated LPA signalling. Thus, multiple RGS proteins are expressed at significantly different levels in cells derived from cancerous and normal ovarian cells and at least two candidate RGS transcripts have been identified to account for the reported regulation of LPA signalling pathways in ovarian cancer cells.
Kinetics of spin coherence of electrons in an undoped semiconductor quantum well

We study the kinetics of spin coherence of optically excited electrons in an undoped insulating ZnSe/Zn$_{1-x}$Cd$_x$Se quantum well under moderate magnetic fields in the Voigt configuration. After clarifying the optical coherence and the spin coherence, we build the kinetic Bloch equations and calculate dephasing and relaxation kinetics of laser pulse excited plasma due to statically screened Coulomb scattering and electron hole spin exchange. We find that the Coulomb scattering can not cause the spin dephasing, and that the electron-hole spin exchange is the main mechanism of the spin decoherence. Moreover the beat frequency in the Faraday rotation angle is determined mainly by the Zeeman splitting, red shifted by the Coulomb scattering and the electron hole spin exchange. Our numerical results are in agreement with experiment findings. A possible scenario for the contribution of electron-hole spin exchange to the spin dephasing of the $n$-doped material is also proposed.
Portable run-time support for dynamic object-oriented parallel processing

Mentat is an object-oriented parallel processing system designed to simplify the task of writing portable parallel programs for parallel machines and workstation networks. The Mentat compiler and run-time system work together to automatically manage the communication and synchronization between objects. The run-time system marshals member function arguments, schedules objects on processors, and dynamically constructs and executes large-grain data dependence graphs. In this article we present the Mentat run-time system. We focus on three aspects—the software architecture, including the interface to the compiler and the structure and interaction of the principle components of the run-time system; the run-time overhead on a component-by-component basis for two platforms, a Sun SparcStation 2 and an Intel Paragon; and an analysis of the minimum granularity required for application programs to overcome the run-time overhead.
A generalized modal shock spectra method for spacecraft loads analysis

Unlike the traditional shock spectra approach, the generalization presented in this paper permits elastic interaction between the spacecraft and launch vehicle in order to obtain accurate bounds on the spacecraft response and structural loads. In addition, the modal response from a previous launch vehicle transient analysis - with or without a dummy spacecraft - is exploited in order to define a modal impulse as a simple idealization of the actual forcing function. The idealized modal forcing function is then used to derive explicit expressions for an estimate of the bound on the spacecraft structural response and forces.
Low temperature compartment formation in feline immunodeficiency virus-infected and uninfected feline kidney cells

This study was to determine if feline immunodeficiency virus (FIV)-infected and uninfected Crandall feline kidney (CRFK) cells exhibited a low temperature (16°C) block in membrane trafficking between transitional endoplasmic reticulum and Golgi apparatus represented by intermediate compartment formation. Cells were cultured at different temperatures and membrane changes involving the Golgi apparatus and Golgi apparatus-associated membrane structures were monitored by electron microscopy and quantitated. With 30 min of incubation, membranes of the Golgi apparatus stack increased in amount at temperatures of 16°C and below compared to temperatures above 18°C. The increase was greatest along the major polarity axis as evidenced by an increased stack height. Neither the number of cisternae per stack nor the average stack diameter (width) was affected by temperature. The response was maximal between 15 and 30 min of low temperature treatment of the cells. Results with cells infected and uninfected with feline immunodeficiency virus were similar. The increase in stack height was due primarily to an increase of membranes at the cis face (cis Golgi apparatus network). At 18°C, membranes of the trans Golgi apparatus network accumulated suggesting that import from the cis Golgi network could proceed at this temperature, whereas exit from the trans Golgi network was still at least partially blocked. Also increased at 16°C and below were numbers of transition vesicles in the space between the Golgi apparatus and the transitional endoplasmic reticulum associated with the cis Golgi apparatus face. The results suggested interruption of the orderly flux of membranes into the Golgi apparatus at 16°C and below. Moreover, the block appeared to be reversible. Upon transfer from 16°C to 37°C, there was a time-dependent decrease in the accumulations of cis compartment membrane accompanied by a corresponding equivalent increase in the membranes of the trans Golgi apparatus compartment.
Value of treadmill exercise test in pre- and postoperative children with valvular aortic stenosis

To determine the utility of graded treadmill exercise test (ETT) in estimating severity of obstruction in postoperative patients with aortic stenosis, we compared results to a nonoperated aortic stenosis group. Cardiac catheterization was performed in all patients. The interval between surgery and ETT in the postoperative group was 7.5 years (range 1.1-12.9). Mean and range values for postoperative versus nonoperative aortic stenosis groups respectively were: age 14.5 (7.9-20.8) versus 12.5 years (5.9-19.7); peak left ventricular pressure 150 (101-190) versus 144 mmHg (100-183); peak systolic ejection gradient (PSEG) 41 (15-75) versus 38 mmHg (14-80); left ventricular end-diastolic pressure (LVEDP) 13.4 (7-20) versus 13.5 mmHg (8-20); and cardiac index 3.7 (2.4-5.6) versus 3.8 liters/min/m2 (2.6-4.9) (p for each = NS). ETT in the nonoperated patients correctly identified all those with PSEG greater than or equal to 50 mmHg (sensitivity 100%), but specificity was 56%, (i.e., the proportion correctly identified with PSEG less than 50 mmHg). By contrast, sensitivity and specificity for postoperative aortic stenosis patients were 67% and 63%, respectively. Furthermore, among nonoperated aortic stenosis patients ST depression on ETT identified those with increased left ventricular end-diastolic pressure. For LVEDP greater than or equal to 12 mmHg, sensitivity was 75% and specificity 100%, corresponding values for postoperative aortic stenosis patients were 45% and 33%, respectively. In the nonoperated aortic stenosis group with a PSEG greater than or equal to 50 mmHg, sensitivity and specificity for ETT-induced change in systolic blood pressure of less than or equal to 30 mmHg were 100% and 56%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Detection over Multiresolution analysis subspaces

The binary detection problem of a known signal in Gaussian noise is transposed to multiple problems of detecting the signal's projection to Multiresolution subspaces. We observe. that subspaces exist where detectability of the projected signal in projected noise is significantly higher than the detectability of the original signal. This. leads to a divide-and-conquer approach that uses optimal detection methods in a numerically economic and stable fashion. The required eigenvalue decompositions, now translated to subspaces, pose new challenges to enable the computations in the children subspaces to be used to reduce the computational load in the parent subspaces. We develop the theoretical relationships of eigenvalue decompositions over subspaces and show empirically how Receiver Operating Characteristic (ROC) change over subspaces. We verify results using various test signals and simulated and real noise data.
What do we need to advance PACS workstations : A critical review with suggestions

The technology for building workstations suitable for the display of most medical images has existed for almost a decade. Yet the diagnostic interpretation process has not shifted form film to such workstations in early as large numbers as had been predicted. While, in a large part, this is due to the high costs for acquisition of picture archiving and communications system equipment, there is also the aspect of physician acceptance. Since the workstation serves as the primary system-to-person interface, an examination of the way in which workstations are designed and the way in which radiologists actually work yields some insight into the relative lack of penetration of workstations into the diagnostic image interpretation task.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Raman and infrared spectra, conformational stability, vibrational assignment and ab initio calculations of but-2-enoyl fluoride

Abstract The Raman (3500-10 cm −1 ) and infrared (3200-50 cm −1 spectra have been recorded of the fluid and solid phases of but-2-enoyl fluoride (crotonyl fluoride) trans -CH 3 CHCHCFO, where the methyl group is trans to the CFO group. From the variable temperature studies of the infrared spectrum of the sample dissolved in liquified Xe, the conformer pair at 836 827 cm −1 has been used to determine a ΔH value of 135 ± 11 cm −1 (387 ± 30 cal mol −1 ), with the s-cis ( syn ) form (two double bonds oriented cis to one another) the more stable form. In the Raman and infrared spectra of the solid, the s-cis conformer seems predominant, but even with repeated annealing a spectrum free of signals from the s-trans ( anti ) conformer could not be obtained. In fact, in some of the infrared spectra, there appeared to be a slight preference for the trans conformer. The asymmetric torsional fundamental of the s-trans conformer was observed at 104.3 cm −1 with two hot bands and that for the s-cis rotamer at 97.0 cm −1 with one hot band. From these data the potential function governing the conformational interchange was determined, and the potential coefficients are: V 1 = −122 ± 1, V 2 = 1993 ± 27, V 3 = 21 ± 1 and V 4 = −88 ± 8 cm −1 . The s-trans to s-cis and s-cis to s-trans barriers were determined to be 2044 and 1942 cm −1 , respectively, with an enthalpy difference between the conformers of 102 ± 29 cm −1 (292 ± 83 cal mol −1 ). The barriers governing the internal rotation of the CH 3 group for the s-trans and s-cis conformers are calculated to be 1060 ± 17 cm −1 (3.03 ± 0.05 kcal mol −1 ) and 1042 ± 23 cm −1 (2.98 ± 0.07 kcal mol −1 ), respectively. A complete vibrational assignment of the normal modes is provided. The structural parameters, force constants, and vibrational frequencies have been determined from ab initio RHF 3-21 G , RHF 6-31 G ∗ and MP 2 6-31 G ∗ calculations, and the theoretical results are compared with the experimental values when appropriate. These results are compared with the corresponding quantities obtained for some similar molecules.
Origin of pyroelectricity in LiNbO 3

We use molecular dynamics with a first-principles-based shell model potential to study pyroelectricity in lithium niobate. We find that the primary pyroelectric effect is dominant, and pyroelectricity can be understood simply from the anharmonic change in crystal structure with temperature and the Born effective charges on the ions. This opens an experimental route to study pyroelectricity, as candidate pyroelectric materials can be studied with x-ray diffraction as a function of temperature in conjunction with theoretical effective charges. We also predict an appreciable pressure effect on pyroelectricity, so that chemical pressure, i.e., doping, could enhance the pyroelectric and electrocaloric effects.
Molecular motors are differentially distributed on Golgi membranes from polarized epithelial cells

Microtubules (MT) are required for the efficient transport of membranes from the trans-Golgi and for transcytosis of vesicles from the basolateral membrane to the apical cytoplasm in polarized epithelia. MTs in these cells are primarily oriented with their plus ends basally near the Golgi and their minus-ends in the apical cytoplasm. Here we report that isolated Golgi and Golgi-enriched membranes from intestinal epithelial cells possess the actin based motor myosin-I, the MT minus-end-directed motor cytoplasmic dynein and its in vitro motility activator dynactin (p150/Glued). The Golgi can be separated into stacks, possessing features of the Golgi cisternae, and small membranes enriched in the trans-Golgi network marker TGN 38/41. Whereas myosin-I is present on all membranes in the Golgi fraction, dynein is present only on the small membrane fraction. Dynein, like myosin-I, is associated with membranes as a cytoplasmic peripheral membrane protein. Dynein and myosin-I coassociate with membranes that bind to MTs and cross-link actin filaments and MTs in a nucleotide-dependent manner. We propose that cytoplasmic dynein moves Golgi membranes along MTs to the cell cortex where myosin-I provides local delivery through the actin-rich cytoskeleton to the apical membrane.
The synthesis of acetaminophen-d4

Acetaminophen-d4 (4′-hydroxyacetanilide-2′, 3′, 5′, 6′-d4) has been synthesized. p-Aminophenol underwent proton exchange in 4N DC1 at 150° for one week. This compound was acetylated in acetic anhydride to diacetyl-p-aminophenol and selectively hydrolyzed in 0.1 N HCl to acetaminophen-d4.
Use of a real‐time continuous glucose monitoring system in children and young adults on insulin pump therapy: patients' and caregivers' perception of benefit

Cemeroglu AP, Stone R, Kleis L, Racine MS, Postellon DC, Wood MA. Use of a real-time continuous glucose monitoring system in children and young adults on insulin pump therapy: patients' and caregivers' perception of benefit. Background: Real-time continuous glucose monitoring systems (RT-CGMS) are a recently introduced technology for type 1 diabetes and experience in children is limited. Objective: To assess patient and caregiver's perception of benefits and disadvantages of RT-CGMS in children or young adults with type 1 diabetes mellitus (DM) on insulin pump therapy. Subjects and Methods: Forty-three subjects (3–25 yr) on insulin pump therapy were included in the study. Thirty-four used RT-CGMS for a short-term trial (4 wk, ST group) and nine as a long-term tool (2–18 months, LT group). Forty subjects or their caregivers completed a questionnaire. Results: On the basis of the questionnaire responses, hypoglycemia prevention was the most common perceived benefit (88%), followed by elimination of hypoglycemia-related anxiety (83%), ease of pattern management (85%), improvement of diabetes control (80%), improvement of quality of life (78%), and ease of diabetes care (78%). Negative effects included irritation/annoyance from the sensor alarm (48%) and insertion site bruising, pain, or irritation (43%). A small percentage of patients who were interested in purchasing the device (12%) decided against using it LT after a 4-wk trial on RT-CGMS. Conclusions: The most common perceived benefits of RT-CGMS are prevention of hypoglycemia and decrease in hypoglycemia-related anxiety. Negative effects are uncommon and seem to be unlikely to affect the decision to use RT-CGMS for a LT. A ST trial seems to be a valuable tool for the patient/caregiver in determining whether to purchase the device and in setting realistic expectations of its potential benefits.
Deferoxamine Reduces Early Metabolic Failure Associated With Severe Cerebral Ischemic Acidosis in Dogs

Background and Purpose Postischemic metabolic injury may be mediated by acidosis and tissue bicarbonate depletion, with consequent iron mobilization and oxygen radical formation during reperfusion. We have previously shown that reducing intracellular pH to below 5.7 and bicarbonate ion to below 1 to 2 mmol/L during hyperglycemic ischemia produces a profound secondary deterioration of brain ATP and cerebral blood flow during reperfusion. This study tested the hypothesis that pretreatment with free deferoxamine ameliorates metabolic decay and delayed hypoperfusion after global hyperglycemic ischemia. In addition, deferoxamine conjugated to a high-molecular-weight starch was administered to determine the importance of an intravascular site of action. Iron-loaded deferoxamine was used to determine whether the iron chelation properties of deferoxamine are important to postischemic viability as distinguished from the agent’s significant radical scavenging potential. Methods Cerebral ATP, phosphocreatine, and pH were measured by 31P magnetic resonance spectroscopy in anesthetized dogs. Tissue bicarbonate concentration was calculated from the Henderson-Hasselbalch equation. Incomplete cerebral ischemia was produced by intracranial pressure elevation for 30 minutes with plasma glucose at 540±15 mg/dL. Free deferoxamine, saline vehicle, hydroxyethyl starch–conjugated deferoxamine, hydroxyethyl starch vehicle, and deferoxamine loaded with equimolar ferric chloride were administered intravenously in five groups of dogs. The dose of deferoxamine was 50 mg/kg before ischemia, 50 mg/kg at the onset of reperfusion, and 50 mg/kg over the 180-minute reperfusion period. Results Ischemic hemispheric blood flow (mean, 6 to 8 mL/min per 100 g), intracellular pH (5.7 to 6.0), and bicarbonate levels (1 to 2 mmol/L) were similar in all groups. During reperfusion, cerebral pH and bicarbonate recovered only in the free-deferoxamine group. Both ATP and phosphocreatine initially increased in all groups, but recovery was sustained only in the free-deferoxamine group. Secondary losses of energy phosphates and cerebral oxygen consumption were observed in all other groups, accompanied by progressive reduction of perfusion. Conclusions These data support the hypothesis that iron-catalyzed oxygen radical production plays an important role in acidosis-mediated mechanisms of ischemic brain injury. The results with free and iron-loaded deferoxamine suggest that iron scavenging is an important, but not necessarily the principal, component of this mechanism. The poor recovery seen with conjugated deferoxamine indicates that the beneficial action of deferoxamine is not localized within the intravascular compartment.
Vitamin D status: a review with implications for the pelvic floor

Vitamin D is a micronutrient vital in calcium homeostasis and musculoskeletal function. Vitamin D insufficiency is a common variant of vitamin D deficiency that shows clinical signs of rickets and osteomalacia. The clinical significance of vitamin D insufficiency is being explored in several medical conditions. However, the most robust work suggests a role in musculoskeletal disease. The pelvic floor is a unique part of the body and the function of which is dependent on interrelationships between muscle, nerve, connective tissue, and bone. Pelvic floor disorders result when these relationships are disrupted. This paper reviews current knowledge regarding vitamin D nutritional status, the importance of vitamin D in muscle function, and how insufficient or deficient vitamin D levels may play a role in the function of the female pelvic floor.
Mechanistic significance of intermittent pulmonary vein tachycardia in patients with atrial fibrillation.

Pulmonary Vein Tachycardia. Introduction: The signie cance of intermittent tachycardia within a pulmonary vein (PV) during an episode of atrial e brillation (AF) is unclear. The aim of this study was to determine the role that intermittent PV tachycardias play in AF. Methods and Results: In 56 patients with AF, segmental ostial ablation guided by PV potentials was performed to isolate the PVs. The characteristics of intermittent PV tachycardias and the inducibility of AF before and after PV isolation were analyzed prospectively. During AF, a PV tachycardia (mean cycle length 130 6 30 msec) with exit block to the left atrium was present in 93% of left superior, 80% of left inferior, 73% of right superior, and 7% of right inferior PVs. The site of shortest cycle length during AF alternated between the PVs and left atrium 1 to 13 times per minute. Complete isolation was achieved in 168 (94%) of 178 targeted PVs. In 99% of PVs, tachycardia resolved upon isolation. AF was persistent before and after PV isolation in 100% and 27% of patients, respectively (P < 0.001). Conclusion: Intermittent bursts of tachycardia are observed within multiple PVs during persistent AF in a majority of patients. After PV isolation, PV tachycardias almost always resolve, and AF is less likely to be inducible or persistent. These observations suggest a dynamic interplay between the atria and PVs, with intermittent bursts of PV tachycardia being dependent on left atrial input and with the probability of persistent AF diminishing when PV tachycardias are eliminated by PV isolation. (J Cardiovasc
Lignoceroyl-CoA ligase activity in rat brain microsomal fraction: topographical localization and effect of detergents and α-cyclodextrin

Abstract Lignoceroyl-CoA ligase activity has been detected in microsomal fractions prepared from rat brain. The synthesis of lignoceroyl-CoA from [1- 14 C]lignoceric acid and CoASH by this enzyme had an absolute dependence on ATP and Mg 2+ ; ATP could not be replaced by GTP [ I. Singh, M. S. Kang, and L. Phillips (1982) Fed. Proc. 41 , 1192]. The product has been characterized as lignoceroyl-CoA by the following criteria: R f on thin-layer chromatography; incorporation of [1- 14 C]lignoceric acid and [ 3 H]CoASH into the product; acid hydrolysis and identification of the radiolabel in lignoceric acid; and methanolysis and identification of the radiolabel in methyl lignocerate by thinlayer chromatography. The optimal concentrations for CoASH, ATP, and Mg 2+ were about 100 μ m , 10 m m , and 5 m m , respectively. Lignoceric acid, solubilized by α-cyclodextrin, Triton X-100, and deoxycholate, was utilized by the lignoceroyl-CoA ligase, but lignoceric acid solubilized by Triton WR-1339 was not. Topographical localization of lignoceroyl-CoA ligase in the plane of rat brain microsomal membranes was determined by the use of Triton X-100, trypsin, and mercury-Dextran, and was compared with the marker enzymes, ethanol acyltransferase and thiamine pyrophosphatase, which are known to be localized on the luminal (inner) surface of the microsomal vesicles. Mercury-Dextran (100 μ m ) and trypsin (trypsin:microsomes, 1:56 w/w) treatment of the microsomes inhibited the lignoceroyl-CoA ligase activity by 70 and 90% without disrupting the microsomal vesicles. Disruption of the vesicles with Triton X-100 increased the activity of both ethanol acyltransferase and thiamine pyrophosphatase by 400% but there was no increase in lignoceroyl-CoA ligase activity. These results suggest that lignoceroyl-CoA ligase is localized on the cytoplasmic surface of the microsomal vesicles.
Synthesis and Evaluation of New Spacers for Use as dsDNA End-Caps

A series of aliphatic and aromatic spacer molecules designed to cap the ends of DNA duplexes have been synthesized. The spacers were converted into dimethoxytrityl-protected phosphoramidites as synthons for oligonucleotides synthesis. The effect of the spacers on the stability of short DNA duplexes was assessed by melting temperature studies. End-caps containing amide groups were found to be less stabilizing than the hexaethylene glycol spacer. End-caps containing either a terthiophene or a naphthalene tetracarboxylic acid diimide were found to be significantly more stabilizing. The former showed a preference for stacking above an A*T base pair. Spacers containing only methylene (-CH(2)-) and amide (-CONH-) groups interact weakly with DNA and consequently may be optimal for applications that require minimal influence on DNA structure but require a way to hold the ends of double-stranded DNA together.
Using Modeling and Simulation to Support Future Medium and Heavy Duty Regulations

Other than in Japan, medium and heavy duty vehicles (MHDVs) are not regulated despite accounting for a significant portion of the fuel consumed (about 26% in the US in 2008). Government agencies worldwide are currently evaluating options to address that issue. Due to the large number of vehicle applications, some of them being "one of a kind", vehicle modeling and simulation offers an attractive solution to medium and heavy duty regulations. This paper discusses the advantages and challenges of vehicle simulation to support regulations.