cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluation of Rh/CexTi1−xO2 catalysts for synthesis of oxygenates from syngas using XPS and TPR techniques

Abstract Rh/CexTi1−xO2 catalysts have been investigated for the synthesis of ethanol from syngas. For this purpose various CexTi1−xO2 (x = 0, 0.25, 0.5, 0.75, and 1) solid solution supports were synthesized using co-precipitation, which is an inexpensive and environmental friendly method. 2 wt% Rh has been deposited over these supports by using wet impregnation method. We have evaluated these Rh catalysts for synthesis of ethanol from syngas at atmospheric pressure and 350 psi. Among, the various catalysts, Rh supported on Ce0.75Ti0.25O2 catalyst exhibit better selectivity toward oxygenates compared to other catalysts. Interestingly, Ti rich samples exhibit higher selectivity toward hydrocarbons while Ce rich samples exhibit higher selectivity toward oxygenated products. The catalytic results at atmospheric pressure show that titania rich catalysts exhibit higher H2 conversion and ceria rich catalysts exhibit higher CO-conversion at 250 °C at atmospheric pressure. Temperature programmed reduction measurements suggest that Rh promotes the cerium surface reduction. X-ray photoelectron measurements show that all the catalysts exhibit peaks due to Ce4+ and Ce3+ oxidations states in the Ce 3d spectra. O1s spectra of activated Rh/TiO2 and Rh/Ce0.5Ti0.5O2 catalysts show two peaks after reduction in hydrogen. One peak is due to the oxygen atoms from the individual oxides and the other peak is from the compound formation between Rh and the support. X-ray photoelectron measurements of activated catalysts also show that Rh/Ce0.5Ti0.5O2 catalyst exhibit higher Rh1+ ions on the surface compared to Rh/TiO2 and exhibits better selectivity toward oxygenated products.
Can Teams Help to Close the Gender Competition Gap

We investigate the effect that competing in teams has on gender differences in choosing to enter competitions. In our experiment, subjects chose whether to compete based on the combined performance of themselves and a teammate. We find that competing in two-person teams reduces the gender competition gap by two-thirds. Independent of the sex of one’s partner, female subjects prefer to compete in teams whereas male subjects prefer to compete as individuals. We find that this result is driven primarily by gender differences in competitive preferences, as opposed to other potential explanations such as risk aversion, feedback aversion or confidence.
Mutagenesis of putative catalytic and regulatory residues of Streptomyces chromofuscus phospholipase D differentially modifies phosphatase and phosphodiesterase activities

Phospholipase D from Streptomyces chromofuscus (sc-PLD) is a member of the diverse family of metallo-phosphodiesterase/phosphatase enzymes that also includes purple acid phosphatases, protein phosphatases, and nucleotide phosphodiesterases. Whereas iron is an essential cofactor for scPLD activity, Mn2+ is also found in the enzyme. A third metal ion, Ca2+, has been shown to enhance scPLD catalytic activity although it is not an essential cofactor. Sequence alignment of scPLD with known phosphodiesterases and phosphatases requiring metal ions suggested that His-212, Glu-213, and Asp-389 could be involved in Mn2+ binding. H212A, E213A, and D389A were prepared to test this hypothesis. These three mutant enzymes and wild type scPLD show similar metal content but considerably different catalytic properties, suggesting different roles for each residue. His-212 appears involved in binding the phosphate group of substrates, whereas Glu-213 acts as a ligand for Ca2+. D389A showed a greatly reduced phosphodiesterase activity but almost unaltered ability to hydrolyze the phosphate group in p-nitrophenyl phosphate suggesting it had a critical role in aligning groups at the active site to control phosphodiesterase versus phosphatase activities. We propose a model for substrate and cofactor binding to the catalytic site of scPLD based on these results and on sequence alignment to purple acid phosphatases of known structure.
On Shear Bands in Ductile Materials

Spatially non-uniform solutions are found here for the field relations that govern the behavior in shear of a class of rigid-plastic materials that have rateindependent response and, after a certain amount of plastic flow, exhibit strain softening, i.e., a decline of yield stress with further flow. As strain softening can destabilize homogeneous configurations and result in the concentration of strain in narrow bands, the constitutive relations have been chosen to account for a possibly important influence upon the stress of the spatial variation of the accumulated strain. It is shown that for simple non-steady shearing flows, the shear strain, as a function of time and position, can be expressed in terms of easily evaluated elliptic functions. The theory yields strain fields showing shear bands that are remarkably similar to those observed in ballistic tests of metals under conditions in which inertial forces are negligible but the combined effects of adiabatic heating and thermal softening result in apparent strain softening. Although quantitative comparison with observation is not yet possible, it is expected that the theory will be applicable to slow deformations of geological materials that are ductile at elevated pressures and temperatures and are often softer after flowing as the result of an accumulation of internal damage with deformation.
Exchange rate based stabilizations under real frictions: The role of endogenous labor supply

Abstract This paper studies exchange-rate-based stabilization programs in the context of a model of a small open economy where labor supply is endogenous. Agents derive utility from both consumption and leisure. In environments where consumption is subject to a cash-in-advance constraint, a cut in the rate of devaluation lowers the nominal interest rate and hence alters the optimal mix of consumption and leisure. The paper shows that in the presence of adjustment costs of investment, a perfectly credible cut in the devaluation rate causes, simultaneously, a consumption and output boom, a cumulative current deficit, a sustained real appreciation of the domestic currency and an increase in labor supply over time. It is also shown that an imperfectly credible stabilization program in this environment would have effects similar to the perfectly credible program but generate richer dynamics such as an initial boom in output followed by a recession which begins prior to the end of the program. The model has clear welfare implications in that permanent reductions in inflation are unambiguously welfare enhancing.
Process informatics tools for predictive modeling: Hydrogen combustion

Predictive modeling of chemical reaction systems is facilitated through development of an automated data-centric infrastructure, Process Informatics Model (PrIMe). Modeling and analysis tools were built to bridge the PrIMe Data infrastructure with DataCollaboration, a framework designed to make inferences from experimental observations in the context of an underlying model. The developed tools were integrated with the PrIMe Workflow Application, allowing users to create and run drag-and-drop applications on the fly. Organizing the data, linking the data to scientific methods, and automating the analysis offer new venues of scientific inquiry, such as evaluating the consistency of heterogeneous data records, making uncertainty-quantified predictions, quantifying the contribution of newly obtained or even hypothetical data to the question of interest, or testing similar “what–if” scenarios. The developed system is demonstrated for the chemical kinetics of hydrogen combustion. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 44: 101–116, 2012
Spectroscopic properties and potential energy curves of SnCl: Comparison with PbCl

Calculs d'interaction de configuration pour sept etats electroniques de SnCl. L'energie de dissociation de l'etat fondamental est evaluee a 3,8 eV
Demand for Fast Food Across Metropolitan Areas

Abstract City data is used to estimate the demand for fast food. Demographic and income differences across cities are found to be less important than market characteristics like population density and outlets per person. Prices are important determinants of fast food demand as well.
Magnetic resonance imaging of acute myocardial infarction in dextrocardia with situs solitus (dextroversion).

Summary The case report of an 88-year-old woman with dextroversion and acute anterior wall myocardial infarction is presented. The patient, who had been diagnosed with dextrocardia 3 years prior to this admission, presented with right-sided chest pain. Coronary angiography demonstrated an 80% proximal left anterior descending artery stenosis which was successfully stented. A cardiac MRI was performed to exclude a left atrial thrombus after an inconclusive echocardiogram. The MRI demonstrated findings consistent with dextroversion, with delayed contrast-enhanced viability sequences confirming a near transmural anterior wall myocardial infarct. To our knowledge, this is the first report illustrating the cardiac MRI findings in such a case.
Gauḍapāda on Imagination

The philosophy of Gauḍapāda, although found in a small treatise, has remained obscure, as both the classical and contemporary approaches to reading this philosopher have overlooked his highly original contributions. This essay explores the scope of imagination in Gauḍapāda?s philosophy, with a focus on terms such as kalpanā and ābhāsa. This reading of Gauḍapāda?s philosophy tallies with some of the findings in contemporary consciousness studies.
Early differential MMP-2 and -9 dynamics during flow-induced arterial and vein graft adaptations

Background Arteries and vein grafts respond differently to reductions in flow, with arteries demonstrating inward remodeling through only limited structural reorganization of the media and vein grafts developing a thickened intima, with little change in the external diameter. In an effort to mechanistically explore the biology of this contrasting behavior, we hypothesized that this differential response in flow-mediated remodeling is driven by unique temporal expression patterns and functional activities of the matrix metalloproteinase (MMP)-2 and -9, key effectors of blood vessel architecture remodeling. Material and methods In rabbits, bilateral carotid vein grafting was coupled with unilateral partial distal ligation to create a sevenfold flow differential between sides. Vein grafts and proximal carotid arteries were then harvested for morphological and biochemical studies at time points ranging from 1 to 14 days. Results Vein grafts demonstrated an early, transient increase in pro-MMP-9 within adherent monocytes and endothelial cells. This was followed by a delayed increase in smooth muscle cell active MMP-2, which was coincident with the onset of intimal thickening at days 7 and 14 and significantly elevated by low flow. In contrast, arteries showed no elevation in pro MMP-9 above baseline, but demonstrated a transient increase in latent MMP-2 preceding the flow-mediated change in vessel diameter. Conclusions These data provide evidence for unique and independent roles of MMP-2 and -9 in the process of hemodynamically driven vascular remodeling.
N-Aminoaziridinylhydrazones: Highly diastereoselective alkylation without chelation, and a syn-directing effect

Abstract The alkylation of C 2 -symmetric N-aminoaziridinylhydrazone anions shows excellent diastereoselectivity despite the absence of chelating groups in the chiral auxiliary. In contrast to other dialkylhydrazones, aziridinylhydrazones exhibit a syn-directing effect analogous to that observed for arenesulfonylhydrazones.
Preconditioning for the Dynamic Simulation of Reaction-Transport Systems

This paper presents an investigation of preconditioning techniques for the transient simulation of reaction-diffusion systems that are commonly encountered in chemical process design applications. Three model-based preconditioners were proposed. Their performance was compared with that of a standard incomplete LU decomposition based preconditioner (P1). Two of the model-based preconditioners, P2 and P3, were constructed using only the transport part of the reaction-diffusion model: One of them was calculated using numerical differentiation while the other was based on analytical formulas. Since the transport properties are commonly assumed to be constant in transient numerical simulations, the resulting preconditioners are timeindependent and need to be calculated only once, at the beginning of the simulation, and thus the efficiency of the simulation is significantly improved. The preconditioner P4 was constructed by adding chemical reaction contributions, updated only when necessary during the entire transient simulation. The numerical results for several test cases show that P4, by adding reaction correction terms, is more effective in improving the speed of the reactor simulation than the other two while maintaining the advantages of easy construction and low computational cost. In addition, it was demonstrated that the preconditioner P4 can also be used as an approximated Jacobian matrix for Newton’s iteration, which may improve the efficiency of the simulation even further.
Potential anticonvulsants. V. The condensation of isatins with C-acetyl heterocyclic compounds

A number of C-acetyl heterocyclic compounds were condensed with isatin and substituted isatins to give a series of 3-hydroxy-3-substituted oxindoles. The products from 2-acetylfuran and isatin, 2-acetylthiophene and isatin, and 2-acetylpyridine and 1-methylisatin were active at 100 mg/Kg in the maximal electroshock seizure test.
Monomeric Silver(I) β-Diketiminate Complexes

New silver(I) β-diketiminate complexes have been prepared and characterized. Monomeric complexes with ethylene (4), triphenylphosphine (5), and IMes (IMes =1,3-dimesitylimidazol-2-ylidene) (8) as well as a dinuclear acetonitrile complex (3) were characterized by 1H NMR, 13C NMR, elemental analysis, and X-ray crystallography. These complexes are stable in the solid state at ambient temperature and inert atmosphere.
Flow Boiling Enhancement in Microchannels With Diffusion Bonded Wire Mesh

Flow boiling and heat transfer enhancement in four parallel microchannels using a dielectric working fluid, HFE 7000, was investigated. Each channel was 1000 μm wide and 510 μm high. A unique channel surface enhancement technique via diffusion bonding a layer of conductive fine wire mesh onto the heating wall was developed. According to the obtained flow boiling curves for both the bare and mesh channels, the amount of wall superheat was significantly reduced for the mesh channel at all stream-wise locations. This indicated that the nucleate boiling in the mesh channel was enhanced due to the increase of nucleation sites the mesh introduced. Both the nucleate boiling dominated and convective evaporation dominated regimes were identified. In addition, the overall trend for the flow boiling heat transfer coefficient, with respect to vapor quality, was increasing until the vapor quality reached approximately 0.4. The critical heat flux (CHF) for the mesh channel was also significantly higher than that of the bare channel in the low vapor quality region. Due to the fact of how the mesh was incorporated into the channels, no pressure drop penalty was identified for the mesh channels. Potential applications for this kind of mesh channel include high heat-flux electronic cooling systems and various energy conversion systems.Copyright © 2007 by ASME
Sympathetic block during spinal anesthesia in volunteers using lidocaine, tetracaine, and bupivacaine

Background and Objectives Spinal anesthesia to high thoracic dermatomes is alleged to result in almost complete block of all sympathetic efferent nerves. To examine the degree of sympathectomy during spinal anesthesia, the sympathetic response to a cold pressor test (CPT) applied to unblocked dermatomes before and during spinal anesthesia was measured with use of three different local anesthetics. Methods Twelve healthy volunteers were studied in a randomized and double-blind fashion on three separate occasions. In random order, each volunteer received approximately equipotent spinal doses of tetracaine 15 mg, bupivacaine 15 mg, and lidocaine 100 mg in hyperbaric solutions. Prior to and 30 minutes after spinal injection of local anesthetic, a CPT was applied for 2 minutes, and changes from baseline resting conditions in five physiologic variables were measured. Results The CPT 1 given before anesthetic administration resulted in an increase in heart rate, mean arterial pressure, cardiac index, and plasma concentrations of norepinephrine and epinephrine. Spinal anesthesia to a median level of T3 resulted in a decrease in mean arterial pressure by 10-12% but did not significantly decrease the other variables. Spinal anesthesia did not change the increase in heart rate or cardiac index in response to the second CPT, but the increase in mean arterial pressure was attenuated compared to the CPT before anesthesia. No increase in norepinephrine or epinephrine concentration was observed during the CPT given during spinal anesthesia. There was no significant relationship between level of analgesia and sympathetic response to stress. Conclusions Spinal anesthesia with hyperbaric solutions of tetracaine 15 mg, bupivacaine 15 mg, and lidocaine 100 mg attenuated sympathetic function but did not produce complete sympathectomy. The effects were independent of the local anesthetic used.
Pre- and post-processing for the finite element method

Abstract The finite element method provides a powerful procedure to mathematically model physical phenomena. The technique is numerically formulated and is effectively used on a broad range of computers. The method has increased in both popularity and functionality with the development of user friendly pre- and post-processing software. Pre-processing software is used to create the model, generate an appropriate finite element grid, apply the appropriate boundary conditions, and view the total model. Post-processing provides visualization of the computed results. This paper addresses the pertinent issues of pre- and post-processing for finite element analysis. It reviews the capabilities that are provided by pre- and post-processors and suggests enhancements and new features that will likely be developed in the near future.
Single-Particle Resonances in the Renormalized Random-Phase-Approximation Treatment of Nucleon-Nucleus Scattering

The method of Garside and MacDonald is used to treat the single-particle resonances in the renormalized random-phase-approximation treatment of scattering. The resonances are shifted by an additional potential to single-particle bound states, which can be handled in the usual manner. The coupling to the continuum is done analytically using separable matrix elements.
Material Tests for LISA

LISA requires several ultra-stable structures such as the reference cavities, the optical benches, and the telescopes. We will present measurements of the stability of various materials for use in LISA.
Surface stress changes induced by the conformational change of proteins.

A potential binding assay based on conformational-change-induced micromechanical motion is described. Calmodulin was used to modify a microcantilever (MCL) by a self-assembled layer-by-layer approach. The results showed that the modified MCL bent when the proteins changed their conformation upon binding with Ca 2+ . The cantilever deflection amplitudes were different under different ionic strengths, indicating different degrees of conformational change of the proteins in these conditions. On the contrary, cantilevers modified by proteins, such as hemoglobin and myoglobin, that do not change conformations upon binding with analytes do not cause the cantilever deflection. These results suggest that the conformational changes of proteins may be used to develop cantilever biosensors, and the MCL system has potential for use in label-free, protein-analyte screening applications.
Conserving biological diversity: A perspective on scope and approaches

Abstract Biological diversity is the variety of life. It encompasses the spectrum of biological organization from gene to biomes, and the spectrum of geographic locations from microsites to the biosphere. Significant losses of biological diversity could affect the future well-being of human life. Extinction of species and simplification of ecosystems diminish future resource options and the ability of natural areas to provide life-supporting ecological services. Major factors that affect biological diversity include conversion of wild areas to agriculture, industry, and other human uses; toxics, pollution, and global climate change; overuse of species by humans; fragmentation of habitats and populations; restoration of species and ecosystems; and management of wild areas for sustainable uses of natural resources. The last two factors are useful in countering the potential negative effects of the others. Reasons for conserving as much of the variety of life as possible include its intrinsic values and its roles in providing current and future resources and in overall environmental quality. Biological diversity, however, is so complex and intangible that its conservation cannot be approached without focusing on specific elements and processes, principal among which are populations of species, communities, ecosystems, and biomes. In the setting of goals for biological diversity we must address specific, achievable objectives for the principal elements of concern in an area. Those goals must be integrated in three major ways. First, they must be integrated into overall conservation plans of public-resource management agencies and private-sector organizations which collectively determine ecological conditions and trends in the area. Obviously, those plans must also be coordinated among the agencies, and the needs of people must be taken into consideration. Second, goals and actions must be integrated up and down geographic scales so that actions taken at individual sites or stands contribute to goals for watershed conditions, which are in turn part of a regional landscape that sustains both the variety of life and meets human resource needs. And third, goals and actions must integrate across the biological spectrum of genetic resources, species, communities, ecosystems, and biomes. This increased need for integration and coordination is a daunting challenge that is fraught with scientific, technological, and political barriers and uncertainties. Nevertheless, it must be done, and soon. The USDA Forest Service is working to refine its roles in an evolving national strategy for conservating biological diversity. This is occurring through individual forest plans, major resource programs, research priorities, public dialogue on policies and priorities, and domestic and international cooperative assistance.
Vibrational assignments for high molecular weight linear polyethylenimine (LPEI) based on monomeric and tetrameric model compounds

Polyethylenimine-based systems provide an interesting alternative to poly(ethylene oxide)-based systems for investigation of polymer electrolyte properties. Vibrational spectra may be used to infer conformations of polyethylenimine, but unambiguous assignments of IR and Raman bands must first be available. Hybrid Hartree−Fock/density functional methods were used to calculate the vibrational frequencies, modes, and infrared intensities for DMEDA (a monomeric model for LPEI) and a tetrameric model for LPEI. These results were then used to help assign the experimentally observed bands in the infrared and Raman spectra of LPEI.
Small‐Scale Retrospective Ground Water Monitoring Study for Simazine in Different Hydrogeological Settings

A ground water monitoring study was conducted for the triazine herbicide simazine at 11 sites in the United States. The study used carefully selected, small-scale sites (average size: about 33 acres) with documented product use and sensitive hydrogeological settings. The sites selected were Tulare County, California (two sites); Fresno County, California; Sussex County, Delaware; Hardee and Palm Beach counties, Florida; Winnebago County, Illinois; Jackson County, Indiana; Van Buren and Berrien counties, Michigan; and Jefferson County, West Virginia. These sites satisfied the following criteria: a history of simazine use, including the year prior to the start of the study; permeable soil and vadose zone; shallow depth to water; no restrictive soil layers above the water table; and gentle slopes not exceeding 2 percent. A variety of crop types, climates, and irrigation practices were included. Monitoring well clusters (shallow and deep) were installed at each site except in California and West Virginia, where only shallow wells were installed. Simazine was monitored at these sites at quarterly intervals for a two-year period during 1986–1988. The results of the study showed that out of 153 samples analyzed, 45 samples showed simazine detections. A substantial majority of the detections (32 out of 45) occurred in Tulare, Fresno, and Jefferson counties. The detections in these areas were attributed to mechanisms other than leaching, such as drainage wells, karst areas, surface water recharge, or point source problems. An additional 11 detections in Van Buren County were apparently due to an unknown upgradient source. Only one detection (in Palm Beach County, Florida) near the screening level of 0.1 ppb was attributed to possible leaching. The results of this investigation support the hypothesis that simazine does not leach significantly under field use conditions.
Inhibition of hydrogen peroxide signaling by 4-Hydroxynonenal due to differential regulation of Akt1 and Akt2 contributes to decreases in cell survival and proliferation in hepatocellular carcinoma cells

Dysregulation of cell signaling by electrophiles such as 4-hydroxynonenal (4-HNE) is a key component in the pathogenesis of chronic inflammatory liver disease. Another consequence of inflammation is the perpetuation of oxidative damage by the production of reactive oxidative species such as hydrogen peroxide. Previously, we have demonstrated Akt2 as a direct target of 4-HNE in hepatocellular carcinoma cells. In the present study, we used the hepatocellular carcinoma cell line HepG2 as model to understand the combinatorial effects of 4-HNE and hydrogen peroxide. We demonstrate that 4-HNE inhibits hydrogen peroxide-mediated phosphorylation of Akt1 but not Akt2. Pretreatment of HepG2 cells with 4-HNE prevented hydrogen peroxide stimulation of Akt-dependent phosphorylation of downstream targets and intracellular Akt activity compared with untreated control cells. Using biotin hydrazide capture, it was confirmed that 4-HNE treatment resulted in carbonylation of Akt1, which was not observed in untreated control cells. Using a synthetic GSK3α/β peptide as a substrate, treatment of recombinant human myristoylated Akt1 (rAkt1) with 20 or 40 μΜ 4-HNE inhibited rAkt1 activity by 29 and 60%, respectively. We further demonstrate that 4-HNE activates Erk via a PI3 kinase and PP2A-dependent mechanism leading to increased Jnk phosphorylation. At higher concentrations, 4-HNE decreased both cell survival and proliferation as evidenced by MTT assays and EdU incorporation as well as decreased expression of cyclin D1 and β-catenin, an effect only moderately increased by the addition of hydrogen peroxide. The ability of 4-HNE to exert combinatorial effects on Erk, Jnk, and Akt-dependent cell survival pathways provides additional insight into the mechanisms of cellular damage associated with chronic inflammation.
Impact of Mindfulness Training on the Behavior of Elementary Students With Attention-Deficit/Hyperactive Disorder

This study investigated the effects of mindfulness training on the behavior of four 8-year-old boys with attention-deficit/hyperactivity disorder. A multiple baseline design was used to investigate whether a multisession mindfulness intervention resulted in increased on-task behaviors in the classroom. Graphic analysis of observation data indicated that the intervention was effective in increasing the percentage of intervals of on-task behavior. In addition, parent and teacher ratings on the Behavior Assessment System for Children, 2nd Edition (BASC-2) generally indicated a decrease in hyperactive behaviors. Conversely, significant changes in pre- and posttest ratings on the BASC-2 Attention Problems Scale were generally not observed.
Convolutive blind separation of speech mixtures using the natural gradient

Convolutive blind separation of speech, also known as the "cocktail party problem", is a challenging task for which few successful algorithms have been developed. In this paper, we explore two novel algorithms for separating mixtures of multiple speech signals as measured by multiple microphones in a room environment. Both algorithms are modifications of an existing approach for density-based multichannel blind deconvolution (MBD) using natural gradient adaptation. The first approach employs non-holonomic constraints on the multichannel separation system to effectively avoid the partial deconvolution of the extracted speech signals within the separation system's outputs. The second approach employs linear predictors within the coefficient updates and produces separated speech signals whose auto-correlation properties can be arbitrarily specified. Unlike MBD methods, the proposed techniques maintain the spectral content of the original speech signals in the extracted outputs. Performance comparisons of the proposed methods with existing techniques show their usefulness in separating real-world speech signal mixtures.
Transcription factor Gbx2 acts cell-nonautonomously to regulate the formation of lineage-restriction boundaries of the thalamus

Relatively little is known about the development of the thalamus, especially its differentiation into distinct nuclei. We demonstrate here that Gbx2-expressing cells in mouse diencephalon contribute to the entire thalamic nuclear complex. However, the neuronal precursors for different thalamic nuclei display temporally distinct Gbx2 expression patterns. Gbx2-expressing cells and their descendents form sharp lineage-restriction boundaries delineating the thalamus from the pretectum, epithalamus and prethalamus, revealing multiple compartmental boundaries within the mouse diencephalon. Without Gbx2, cells originating from the thalamus abnormally contribute to the epithalamus and pretectum. This abnormality does not result from an overt defect in patterning or cell-fate specification in Gbx2 mutants. Chimeric and genetic mosaic analysis demonstrate that Gbx2 plays a cell-nonautonomous role in controlling segregation of postmitotic thalamic neurons from the neighboring brain structures that do not express Gbx2. We propose that, within the developing thalamus, the dynamic and differential expression of Gbx2 may be involved in the specific segregation of thalamic neurons, leading to partition of the thalamus into different nuclei.
Evidence for an essential histidine residue in rabbit liver aryl sulfatase A

Abstract A detailed study of the pH dependence of the Michaelis-Menten constants ( V and K m ) of aryl sulfatase A (EC 3.1.6.1) from rabbit liver indicates that at least two functional groups (p K 's ~4.3 and ~7 in the enzyme-substrate complex) participate in the enzymic degradation of substrate. Aryl sulfatase A is inactivated by diethyl pyrocarbonate (ethoxyformic anhydride). The enzyme that has been modified with this reagent can in turn be reactivated by treatment with hydroxylamine. The pH dependence of inactivation reveals a reactive group having a p K of 6.5–7.0. The results indicate that at least one histidine plays an important catalytic role in rabbit liver aryl sulfatase A, consistent with the results of earlier workers who employed diazotized sulfanilic acid. Phosphate ion, a competitive inhibitor, partially protects the enzyme from inactivation by diethyl pyrocarbonate whereas sulfate ion, also a competitive inhibitor, increases the rate of inactivation by diethyl pyrocarbonate. This result is of particular significance in view of the anomalous kinetics of aryl sulfatase A. The kinetic effects of even small amounts of sulfate ion impurities in many commercial sulfate ester substrate preparations is also discussed.
Truncus bicaroticus and an aberrant right subclavian artery contributing to internal jugular venous line misplacement into the carotid artery

Truncus bicaroticus, or common origin of the carotid arteries, is extremely rare and has been described sparsely in the literature. It has been reported as an incidental finding during cadaveric dissection and as an anatomic variant found during routine angiography. We report the case of a 75-year-old woman with a previously unknown truncus bicaroticus and an aberrant right subclavian artery in whom the anatomic variations contributed to an arterially placed central venous catheter remaining undetected. This catheter misplacement was suspected after the patient developed an embolic stroke, and subsequent studies demonstrated the truncus bicaroticus and intra-arterial catheter placement. To our knowledge, this is the first case reporting a truncus bicaroticus associated with an aberrant right subclavian artery.
Beliefs and opinions about hypnosis held by the general public: a systematic evaluation.

Abstract A study was conducted to systematically evaluate the general public's beliefs and opinions about hypnosis as well as to ascertain the sources of their beliefs. The evaluation was based on four samples representing different ages, socio-economic backgrounds, interests, and geographical locations. A 27 item, two-page questionnaire was developed to evaluate the opinions on a wide variety of topics related to hypnosis and clinical applications of hypnosis. The results indicate that although the different sample groups obtain their information about hypnosis from different sources, their beliefs about hypnosis are remarkably consistent. While the results indicate an interesting mix of ideas about hypnosis, some results indicate that most people have a positive view of the therapeutic benefits, with a vast majority of respondents believing that it reduces the time that is usually required to uncover causes of a person's problems and that hypnotized persons can undergo dental and medical procedures with...
Carbon Monoxide and Hydrogen Detection by Anatase Modification of Titanium Dioxide

From the viewpoint of industrial and automobile exhaust pollution control, a sensor capable of detecting and measuring the concentration of harmful gases such as carbon monoxide and hydrogen in the ambient is desired. This paper describes the development and use of a titania (TiO2)-based semiconducting oxide material as a reliable and rugged CO and H2 gas sensor in the temperature range of 773 to 1073 K. Significant change in the sensing characteristic of the anatase modification of TiO2 was observed when admixed with an insulating second phase, such as alumina or yttria. In the case of TiO2–10 wt% Al2O3, the sensor response was found to be exclusively dependent on the hydrogen concentration alone; the presence of CO or CO2 did not affect the sensitivity. On the other hand, the sensor based on TiO2–10 wt% Y2O3 showed increased sensitivity to CO and decreased sensitivity to H2, compared to that of the undoped TiO2. Addition of elemental iron, in small concentration, to the two-phase mixture of titania and yttria seemed to further improve the sensitivity and selectivity of the latter to CO.
Doppler Velocimetry of the Umbilical and Uteroplacental Circulation: A Critical Review

During the past 8 years, there have been more than 300 articles published describing Doppler studies in the field of obstetrics. This review will analyze the data dealing with the umbilical and uteroplacental circulation. This is being done with the goal of formulating an opinion of the role of Doppler in the practice of clinical obstetrics. We have concluded from prospective studies that there is no clear definition of abnormal umbilical flow velocity before 30 weeks, except for absent end-diastolic velocity after the 20th week. Most of the prospective studies on the uteroplacental circulation have suffered from a lack of knowledge of the umbilical circulation, or only one uterine artery was studied. Most investigations until now have focused on demonstrating the pathophysiological correlations with Doppler studies. With the exception of a few dissenting voices, most have demonstrated strong correlations at probability levels of < 0.01. A few studies have emerged that have attempted to evaluate Doppler as a screening or surveillance tool. The results have not been encouraging. In populations with a low perinatal mortality, it will be difficult to prove that Doppler will reduce perinatal mortality. Studies of Doppler efficacy will have to be designed to show improved usage and efficacy of fetal surveillance. Since Doppler uniquely identifies the fetus at risk for hypoxia before term, it could replace our current risking system for the detection of fetal disease. This implies a reduction in the need for serial nonstress test, contraction stress test, and ultrasounds for amniotic fluid volume in those pregnancies with normal uterine and umbilical flow velocity.
Archaeal histones: structures, stability and DNA binding

Structures, stability and DNA-binding properties have been established for archaeal histones from mesophiles, thermophiles and hyperthermophiles. Most archaeal histones are simply histone folds that are stabilized by dimer formation. Archaeal histones and the histone folds of the eukaryotic nucleosome core histones share a common ancestry and bind and wrap DNA similarly using conserved residues. The histone-fold residues that stabilize dimer–dimer interactions within an archaeal histone core contribute to determining archaeal histone–DNA affinity.
TM-mode coupling coefficients in guided-wave distributed feedback lasers

An equation is derived for TM-mode coupling coefficients in guided-wave distributed feedback (DFB) lasers. Results for GaAs:GaAlAs double-heterostructure lasers with rectangular, triangular, and sawtooth-shaped teeth, various Bragg diffraction orders, and transverse mode numbers are presented for TM modes and compared with those for TE modes. Generally, but not always, coupling coefficients for TE modes exceed those for TM modes.
Understanding crisis communications: Examining students’ perceptions about campus notification systems

Following the 2007 shootings at Virginia Tech, colleges and universities nationwide sought to install new emergency notification systems or overhaul existing systems to alert students in the event a similar incident took place on their campus. While researchers have begun to explore the effectiveness of such systems and how they are being employed, a noticeable gap exists in the literature in respect to how this technology is being utilized by members of the campus community. The present study, conducted at a large southwestern university, sought to fill this void by examining the perceptions and employment of the system by universities’ largest segment of users – students. The findings provide continued support for the use of multimodal systems, but also indicate that more education and advertising is needed to increase student engagement with these systems. Limitations of the study, directions for future research, and related policy implications for universities also are discussed.
Artificial dermis for major burns. A multi-center randomized clinical trial.

This communication presents an 11-center prospective randomized trial using the artificial dermis invented by Burke and Yannas. Patients with life-threatening burns who underwent primary excision and grafting within 7 days of injury had comparable sites randomized to receive either the artificial dermis (study site) or the investigator's usual skin grafting material (control site). Control materials were autograft, allograft, xenograft, or a synthetic dressing. Epidermal grafts were applied to the study site during a second operation, and surviving patients were followed for 1 year after grafting. One hundred thirty-nine sites on 106 patients were studied. Mean burn size was 46.5 +/- 15% mean total body surface (TBSA). Overall mortality was 13%, and mean hospital stay was 68 +/- 45 days. Median artificial dermis take was 80% compared with 95% for all comparative sites, but the take was equivalent to that of all nonautograft control materials. Results with the artificial dermis improved slightly as the investigators became more familiar with the material. Donor site thickness for the study site averaged .006'' +/- .002'' compared to .013'' +/- .018'' for control (p less than .0001) and the epidermal donor site healed an average of 4 days sooner (10 +/- 6 vs. 14 +/- 8 days) (p less than .0001). As the wounds matured during the first year, both patients and surgeons felt that both sites became more comparable in appearance and function. At the completion of the study, there was less hypertrophic scarring of the artificial dermis, and more patients preferred the artificial dermis to the control graft. Artificial dermis with an epidermal graft provides a permanent cover that is at least as satisfactory as currently available skin grafting techniques, and uses donor grafts that are thinner and donor sites that heal faster.
Use Multi-Objective Optimization for Designing Cloaks With Acoustic and Elastic Materials

The various optimization schemes have been recently shown to be a capable tool for designing acoustic cloaks based on Cummer-Schurig prescription without requiring material singularity. However, when using an optimization scheme to optimize a cloak at one specified frequency, sometimes it is observed that the cloaking effect deteriorate at other frequencies. This paper explores the use of multi-objective optimization approach such that the cloaking performance is maintained over a wide range of frequencies. Two examples are presented. The first cloak is comprised of all aocustic layers, and the second cloak is comprised of a mixture of acoustic and elastic layers. The results show the effectiveness of the multi-objective optimization approach on maintaining cloaking performance over a specified frequency range.Copyright © 2012 by ASME
The effects of patient characteristics on ambulatory test ordering

Abstract To investigate the relationship of patient characteristics and the use of ambulatory testing services, we examined patterns of test use for 351 patients with chronic uncomplicated hypertension, cared for by 30 private practice internists. We studied the use of visits and diagnostic tests in relation to patients' sex, marital status, obesity, employment status, occupational class, insurance coverage and severity of illness in terms of age, extent of blood pressure elevation and number of medications used in treatment. Testing services accounted for 63% of the total expenditure for testing and physician services. Females and patients with greater severity of disease had higher visit rates, and age was significantly related to increased test use. Marital status, obesity and socioeconomic characteristics were not strongly associated with patterns of testing. Our results suggest that patterns of testing for hypertensive patients are related to severity of illness in terms of age but not to patients' socioeconomic characteristics.
Challenges for emerging African democracies

When the Soviet Union collapsed, there was euphoria in the West that democracy would “snowball” from Eastern Europe to “some Arab and African countries,” as Samuel Huntington put it. After Francis Fukuyama declared the “end of history” it became apparent that the “democracy” Huntington was referring to was indeed liberal democracy. It is thus understandable that today tenets of classical liberalism (individual rights, private property, free market, and limited government) are commonly used in reference to democracy. It is such interpretations of democracy in terms of Western experience that troubles some observers of the Western imposition of democracy on formerly dictator‐ruled countries. Thomas Carothers, a senior associate at the Carnegie Endowment for International Peace, points out the paradoxical fact that the West is “promoting democracy in other countries precisely at a time when the health of their own democratic systems is in doubt.” Because of such concerns and the past dismal failure of Wester...
Repression of the Human Glycoprotein Hormone α-Subunit Gene by Glucocorticoids: Evidence for Receptor Interactions with Limiting Transcriptional Activators

Expression of the glycoprotein hormone alpha gene is regulated divergently by glucocorticoids in different cell types. Coexpression of the glucocorticoid receptor (GR) with an alpha-CAT reporter gene caused activation of alpha promoter activity in fibroblasts, but repression in JEG-3 choriocarcinoma cells, indicating that cell-specific factors dictate positive vs. negative regulation of this promoter by GR. Cell-specific sequences and other enhancer elements in the the alpha gene have been relatively well characterized in JEG-3 cells, and this model was used to further examine the mechanism of transcriptional repression by glucocorticoids. Promoter mutagenesis indicated that the degree of GR-mediated repression was impaired by a variety of deletional and site-directed mutations between -171 and -111 bp, a region that includes both cell-specific and cAMP response elements (CREs). In an attempt to further localize a negative glucocorticoid response element (GRE) sequence, binding studies were used to assess GR interactions with alpha promoter DNA sequences. Using avidin-biotin complex DNA binding assays, a series of overlapping alpha promoter DNA sequences between -170 to 29 basepairs were tested, but each failed to bind GR, whereas a control GRE avidly bound receptor. Similarly, in competition assays in transfected CV-1 cells, the alpha gene 5'-flanking sequence did not compete for GR stimulation of a glucocorticoid responsive reporter gene, whereas a sequence that contains known GR-binding sites (murine mammary tumor virus) effectively inhibited GR-mediated expression. The absence of high affinity GR-binding sites in the alpha promoter suggested that mutations that affected GR inhibition may have eliminated recognition sites for transactivators, which are themselves targets for the GR, rather than altering specific negative GRE sites in the DNA sequence. To examine this possibility, GR repression was studied using chimeric transcription factors. The transcription-activating domains of several different proteins (CREB, thyroid hormone receptor, or VP16) were linked to the DNA-binding domain of Gal-4, and transcription was driven by the Gal-4 recognition site (UAS). GR markedly repressed transactivation by Gal-4-CREB and, to a lesser degree, the Gal-4-thyroid hormone receptor and Gal-4-VP16 chimeric proteins. Repression occurred when UAS was linked to either the alpha promoter or to the E1B promoter. Thus, inhibition occurs in the absence of either the CRE or the proximal alpha promoter. These results support a mechanism in which GR-mediated repression in JEG-3 cells occurs by receptor interference with the transactivating potential of enhancer-binding proteins or associated transcription factors.