cssi/SciSciGPT-SciSciNet huggingface dataset:
TEMPERATURE INDEPENDENT THERMAL EXPANSIVITIES OF SODIUM ALUMINOSILICATE MELTS BETWEEN 713 AND 1835 K

Abstract The thermal expansivities of eight sodium aluminosilicate liquids were derived from the slope of new volume data at low temperatures (713−1072 K) combined with the high temperature (1300−1835 K) volume measurements of Stein et al. (1986) on the same liquids. Melt compositions range from 47−71 wt% SiO2, 0−31 wt% A1203, and 17−33 wt% Na2O; the volume of albite supercooled liquid at 1092 K was also determined. The low temperature volumes were derived from measurements of the glass density of each sample at 298 K, followed by measurements of the glass thermal expansion coefficient from 298 K to the respective glass transition interval. This technique takes advantage of the fact that the volume of a glass is equal to the volume of the corresponding liquid at the limiting fictive temperature (T′f), and that T′f can be approximated as the onset of the rapid rise in thermal expansion at the glass transition in a heating curve (Moynihan, 1995). No assumptions were made regarding the equivalence of enthalpy and volume relaxation through the glass transition. The propagated error on the volume of each supercooled liquid at T′f is ∼0.25%. Combination of these low temperature data with the high temperature measurements of Stein et al. (1986) allowed a constant thermal expansivity of each liquid to be derived over a wide temperature interval (763−1001 degrees) with a fitted 1σ error of 0.6–4.6%; in every case, no temperature dependence to dV/dTliq could be resolved. Calibration of a linear model equation leads to fitted values ± 1σ (units of cm3/mole) for V ¯ S i O 2 (26.91 ± .04), V ¯ A l 2 O 3 (37.49 ± .12), V ¯ N a 2 O (26.48 ± .06) at 1373 K, and d V ¯ N a 2 O / d T (7.64 ± .08 × 10-3 cm3/mole-K). The results indicate that neither Si02 nor Al2O3 contribute to the thermal expansivity of the liquids, and that dV/dTliq is independent of temperature between 713–1835 K over a wide range of liquid composition. Calculated volumes based on this model recover both low and high temperature measurements with a standard deviation
Binding of the Aflatoxin-Glutathione Conjugate to Mouse Glutathione S-Transferase A3-3 Is Saturated at Only One Ligand per Dimer

Abstract The binding of two different reaction products (p-nitrobenzyl glutathione and the aflatoxin-glutathione conjugate) to mouse glutathione S-transferase A3-3 (mGSTA3-3) has been measured using equilibrium dialysis and a direct fluorescence quenching technique. As expected, p-nitrobenzyl glutathione was found to bind with a stoichiometry of 2.24 ± 0.17 mol/mol of dimeric enzyme. However, the much larger aflatoxin-glutathione conjugate, 8,9-dihydro-8-(S-glutathionyl)-9-hydroxyl-aflatoxin B1 (AFB-GSH), was found to bind with a stoichiometry of 1.12 ± 0.08 mol/mol of dimeric enzyme. p-Nitrobenzyl glutathione bound mGSTA3-3 with a dissociation constant (Kd) of 59 ± 17 µM while the aflatoxin-glutathione conjugate bound the enzyme with a Kd of 0.86 ± 0.19 µM. Glutathione competitively inhibited binding of AFB-GSH to mGSTA3-3 with a Ki of 1.5 mM, suggesting that AFB-GSH was binding to the enzyme active site. Although AFB-GSH bound to mGSTA3-3 with a stoichiometry of 1 mol/mol of dimeric enzyme, AFB-GSH completely inhibited activity toward 1-chloro-2,4-dinitrobenzene, indicating that AFB-GSH binding to one active site alters affinity for 1-chloro-2,4-dinitrobenzene in the active site of the other subunit. To our knowledge, this is the first report of a glutathione S-transferase reaction product which binds to the enzyme with a stoichiometry of 1 mol/mol of dimer.
Vapor-liquid and liquid-liquid equilibria and critical states of water + n-decane mixtures

Abstract vapor—liquid equilibrium and liquid-liquid equilibrium are observed in disjointed regions at 573.2, 593.2, and 613.2 K for mixtures of water + n-decane at pressures up to 230 bar. vapor—liquid critical states are determined at the temperatures studied.
Electronic Structure and Magnetism of Metal Surfaces, Overlayers and Interfaces

As is clear from the subject of this NATO Institute, the importance of low-dimensional systems (including surfaces, interfaces and thin films) in determining the physical properties of technologically important materials has stimulated theoretical efforts to determine from first principles a detailed understanding of their chemical, electronic and mechanical properties. Fortunately, this has now been become possible as a result of the dramatic advances in condensed matter theory made in the last decade, driven in large part by new and sophisticated experiments on high purity materials which have been well and carefully characterized. Particularly in electronic structure, these advances may be attributable directly to the close collaboration of theoretical and experimental researchers. Indeed, the new-found ability to apply fundamental theoretical concepts to real materials (rather than to simple model systems) made possible by utilizing the continued rapid development of computer power, has served to fill the increasingly urgent demand of experimentalists for theoretical interpretation of their data. Also, in some cases, these computational efforts can be used to provide data which would be currently impossible or impractical to obtain experimentally. This development has been an essential element in the phenomenal growth seen in this area of materials science.
The photopic negative response of the flash electroretinogram in multiple sclerosis.

Purpose. To use the photopic electroretinogram (ERG) to evaluate retinal function in eyes of multiple sclerosis (MS) patients with and without a history of optic neuritis (ON) and to compare the functional and structural status of the inner retina.
SU-GG-I-73: Investigation of the Relationship Between the Contrast-Detail Figure of Merit IQFinv and Three Characteristic Parameters of the Contrast-Detail Curve

Purpose: To investigate the relationship between the figure of merit IQFinv that is estimated by the CDRAD Analyzer software as an overall descriptor of the contrast‐detail characteristics of a radiographicimage of the CDRAD phantom, and the fitted contrast‐detail curve parameters: limiting object size (object diameter below which the threshold contrast must be increased by more than a pre‐set value for the object to be detectable), limiting threshold contrast (the threshold contrast of the limiting object size), and large object threshold contrast (the threshold contrast of the object with the largest diameter). Method and Materials: We analyzed CDRAD phantom images acquired with four different digital radiographicdetectors using x‐ray beams with HVL of 7.1 and 10.2 mm Al for each detector, and five different radiographic exposures for each beam quality. The IQFinv and a scatter plot of the contrast‐detail curve were generated for each image. These plots where best‐fitted with S functions, and the contrast‐detail curve parameters were determined from these functions. Results: For a large range of IQFinv (i.e. ∼7 to ∼2) the limiting object size and the limiting threshold contrast generally increase (in this case, from ∼0.5 to ∼1.4 mm and ∼0.1 to ∼0.7% respectively) as IQFinv decreases. For smaller ranges of the IQFinv (i.e. 6.0–8.0 or 3.0–5.0) this relationship for both parameters appears significantly weaker, considering the pool of images from all four detectors. This may be due to the uncertainty in the IQFinv estimate, the selection of the pre‐set value in the determination of the limiting object size, and the fitting parameters of the contrast‐detail curves. The relationship between IQFinv and large object threshold contrast is less pronounced. Conclusion: IQFinv becomes a more accurate descriptor/comparator of the contrast‐detail characteristics of digital imaging systems if it is combined with the proposed fitted contrast‐detail curve parameters.
In situ Phase Transition Study of Nano- and Coarse-Grained TiO2 Under High Pressure/Temperature Conditions

A comparative phase transition study of nanocrystalline and micro-TiO2 has been conducted under high pressure–temperature (P–T) conditions using energy-dispersive synchrotron x-ray diffraction (XRD). Our study reveals that on compression at room temperature, the micro-tetragonal anatase-type TiO2 started to transform to the orthorhombic columbite-type TiO2 near 1.6 GPa. In contrast, we did not observe this phase transition in nano-anatase at pressures of up to 8.5 GPa. At 8.5 GPa, by applying moderate heat, both samples were transformed completely to columbite-type TiO2 almost simultaneously, indicating that heat treatment could significantly expedite this phase transition. These columbite-type TiO2 phases were quenchable because after cooling them to room temperature and decompressing them to 2.0 GPa, the XRD patterns displayed no changes in comparison with those collected at 8.6 GPa and 1270 K. At 2 GPa, we heated the specimens again, and the rutile-type TiO2 started to emerge around 970 K. This phase was also quenchable after cooling and releasing pressure to ambient conditions. The grain size effects on the phase transition were discussed based on the kinetics mechanism. This study should be of considerable interest to the fields of materials science and condensed matter.
Trees and herbs killed by an earthquake ∼300 yr ago at Humboldt Bay, California

Evidence of rapid seismic-induced subsidence at Humboldt Bay, California, is produced by analyses of annual growth rings of relict Sitka spruce [ Picea sitchensis (Bong.) Carr.] roots and entombed herbaceous plants. These results add to previously reported evidence that an earthquake caused subsidence ∼300 yr ago at Mad River slough, California. Both types of remains are rooted in buried soils that stood at or above the high-tide level until the area subsided at least 0.5 m into the intertidal zone. Burial by intertidal muds took place quickly enough to preserve the herbs in the growth position. Analysis of the annual growth rings of the tree roots shows that all died within four growing seasons, but the time of root death varies even among roots of the same tree. With no central nervous system, tree cells do not die simultaneously throughout the organism. The 0.5 to 1.5 m of subsidence, as evidenced by stratigraphy and sedimentology, was not enough to kill all the trees even in one season. Although such gradual death could be due to rapid aseismic subsidence, the tree deaths and preserved herbs are much better explained by sudden coseismic subsidence.
Semiempirical theory of surface tension of binary systems

Surface tensions of several binary mixtures are computed using the gradient theory of inhomogeneous fluids. The interfacial influence parameters are determined from mixing rules and pure fluid experimental tensions. A comparison of the compositional dependence of the predicted and experimental tensions indicates that the best results for nonpolar hydrocarbons are obtained from a geometric mixing rule for the influence parameter. Predicted tensions vs. composition for nonpolar systems are in excellent agreement with experiment, generally lying within 2% of observed data. Predictions are poor for alcohol solutions.
Functional significance of isoform diversification in the protocadherin gamma gene cluster

The mammalian Protocadherin (Pcdh) alpha, beta, and gamma gene clusters encode a large family of cadherin-like transmembrane proteins that are differentially expressed in individual neurons. The 22 isoforms of the Pcdhg gene cluster are diversified into A-, B-, and C-types, and the C-type isoforms differ from all other clustered Pcdhs in sequence and expression. Here, we show that mice lacking the three C-type isoforms are phenotypically indistinguishable from the Pcdhg null mutants, displaying virtually identical cellular and synaptic alterations resulting from neuronal apoptosis. By contrast, mice lacking three A-type isoforms exhibit no detectable phenotypes. Remarkably, however, genetically blocking apoptosis rescues the neonatal lethality of the C-type isoform knockouts, but not that of the Pcdhg null mutants. We conclude that the role of the Pcdhg gene cluster in neuronal survival is primarily, if not specifically, mediated by its C-type isoforms, whereas a separate role essential for postnatal development, likely in neuronal wiring, requires isoform diversity.
Nitrogen modification of highly porous carbon for improved supercapacitor performance

Nitrogen is added to porous carbon, in both the bulk network as heteroatoms and coated on the surface of the pores, to increase the capacitance of electrodes for supercapacitor applications. Surface modification increases the amount of nitrogen by four times when compared to unmodified carbon that only contains nitrogen in the bulk. Pyrolysis of the modified carbon at a lower temperature also retains up to three times more nitrogen than high temperature pyrolysis. The surface modification dramatically improves the wetting behavior of the porous carbon and produces a capacitance that is nearly twice that of the unmodified carbon through a combination of double-layer formation and pseudocapacitive reactions.
Treatment with MDMA from P11-20 disrupts spatial learning and path integration learning in adolescent rats but only spatial learning in older rats.

Previous studies in rats showed that postnatal day (P)11–20 exposure to ±3,4-methylenedioxymethamphetamine (MDMA, ecstasy) causes learning and memory deficits in adulthood. The emergence and permanence of these learning deficits are currently unknown. This study was designed to investigate learning and memory deficits in adolescent (P30 or P40) and older (P180 or P360) rats exposed to MDMA from P11–20. Within each litter half the animals were exposed to MDMA (20 mg/kg) and half to saline (SAL) twice a day (8 h apart) from P11–20. In experiment (exp) 1, behavioral testing began on either P30 or P40, whereas in exp 2, testing began on either P180 or P360. Offspring were tested in the Cincinnati water maze (CWM), a test of path integration learning (2 trials/day for 5 days), and the Morris water maze (MWM) (three phases, with 5 days of 4 trials/day and a probe trial on the sixth day per phase). MDMA-treated rats took longer to find the platform and traveled a greater distance to find the platform at all ages tested in all phases of the MWM. MDMA-treated animals also spent less time in the target quadrant during probe trials. In the CWM, P30 and P40 animals took longer to find the goal and committed more errors in locating the goal, while P180 and P360 MDMA-treated animals performed similarly to SAL-treated animals. The data suggest that the spatial learning and memory deficits induced by MDMA are long lasting, while the path integration deficits recover over time.
Deoxyspergualin: Phase I clinical, immunologic and pharmacokinetic study

Deoxyspergualin (DSG) is an analog of the polyamine spergualin with preclinical evidence of activity in murine and human tumor models. This phase I study examined a 120 h continuous infusion schedule in 56 patients with refractory solid tumors at doses ranging from 80 to 2792 mg/m2/day. Dose-limiting toxicity was reversible hypotension and appeared to be associated with plasma levels of DSG > 4 micrograms/ml. Other dose-dependent effects noted were pruritus and circumoral paresthesias. Myelosuppression and gastrointestinal toxicities were mild and sporadic. Two patients with refractory head and neck cancer had minor responses. The recommended phase II dose on this schedule is 1800 mg/m2. Additional monitoring to identify immunologic properties included immunophenotyping of peripheral lymphocytes and cytotoxic activity by means of standard 51Cr-release assays. These studies revealed a non-dose-dependent increase in the number of cells expressing T cell antigens predominantly the T suppressor (CD8) phenotype posttreatment. In three patients, a mild increase in LAK activity was noted post-treatment without a consistent relationship to dose or change in cell surface antigens. Pharmacokinetic studies were completed on 26 patients ranging from doses of 80 to 2792 mg/m2. The average plasma concentration ranged from 0.07 to 7 micrograms/ml. DSG was rapidly cleared from the plasma with a mean terminal half-life of 1.9 h. Mean total body clearance was 25.24 l/h/m2. Further in vivo immunologic studies should be pursued while the agent is studied in fixed dosage phase II clinical trials.
Oscillator strengths of CH3 in the vacuum ultraviolet

Abstract Measurements of the oscillator strenghts for several CH 3 transitions in the vacuum ultraviolet are reported. The oscillator strengths for the γ 1 , δ 1 , γ 2 , β 2 and combined δ 2 and γ 3 Rydberg transitions are 0.015 (6), 0.0011 (5), 0.0099 (40), 0.0032 (16) and 0.0059 (25), respectively, where the number in parentheses is the uncertainty in the last digit(s) of the oscillator strength.
Semantic Relatedness Measures for Identifying Relationships in Product Development Processes

The Semantic Web, especially in relation to ontologies, provides a structured, formal framework for knowledge interoperability. This trait has been exploited by both the biomedical community in development of the Human Gene Ontology [1] and also by geographers in development of geospatial ontologies [2]. Using semantic relatedness techniques, researchers from both communities have been able to develop and integrate comprehensive knowledge bases. Beyond knowledge integration, semantic relatedness techniques have also been able to provide each community with a unique insight into relationships between concepts in their respective domains. In the engineering community, semantic relatedness techniques promise to provide similar insight into product development processes. This paper explores the application of semantic relatedness techniques to ontologies as a means towards improved knowledge management in product development processes. Several different semantic relatedness techniques are reviewed, including a recently developed meronomic technique specific to domain ontologies. Three of these techniques are adopted to create a semantic relatedness measure specifically designed to identify and rank underlying relationships that exist between aspects of the product development process. Four separate case studies are then presented to evaluate the relative accuracy of the developed algorithm and then determine its effectiveness in exposing underlying relationships.Copyright © 2009 by ASME
Intravascular ultrasound imaging of coronary arteries. Is three layers the norm

BACKGROUNDThe purpose of this study was to evaluate the significance of the three-layered appearance of coronary arteries in adolescence and adults from intravascular ultrasound scans and to correlate these observations with histopathology.METHODS AND RESULTSSixteen intact hearts were excised at autopsy from patients with no clinical history of coronary artery disease. The patients' ages ranged from 13 to 55 years. A 30-MHz ultrasound imaging catheter was used to obtain images throughout the epicardial coronary vasculature. A total of 72 image cross sections was marked by epivascular sutures, and the corresponding histological sections were examined. Ultrasound images were classified into two groups: images exhibiting three-layered appearance and images without distinct layering. Histological analysis revealed a significantly greater degree of intimal thickening in segments with three layers (243 +/- 105 microns) than in nonlayered segments (112 +/- 55 microns). Discriminant analysis of these data predict...
Elemental surface enrichment in flame synthesis: A mechanism associated with particle melting-solidification

Elemental surface enrichment is important for functionalities of flame-synthesized particle materials, but its mechanism is poorly understood. In this paper, a mechanism associated with particle melting-solidification is proposed based on an experimental study. Y2O3:Eu particles were generated by flame assisted spray pyrolysis (FASP), using H2/O2 flames or H2/air flames. The particles were analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD), inductively coupled plasma mass spectrometry (ICP-MS), and X-ray photoelectron spectroscopy (XPS). H2/O2 flames resulted in particles with Eu surface enrichment, i.e. the surface Eu concentration was several times higher than the overall Eu concentration; there was no elemental surface enrichment in particles from H2/air flames. The Eu surface enrichment in H2/O2 flames was attributed to elemental partitioning during solidification of molten Y2O3:Eu particles; in H2/air flames the particles did not melt and hence there was no elemental surface enrichment. The findings of this study suggest that elemental surface enrichment may be a common phenomenon for binary metal oxide particles that experience melting-solidification. Such particles should be examined for elemental surface enrichment, both for understanding their functionality and for their potential biological effects.
Plasma-Enhanced Generation of Stable PAA-and PVP-based Multi-layer Structures

Oxygen/water vapor-plasma treated polished aluminum substrates were coated with poly(acrylic acid) (PAA) using deeping-coating technique, and subsequently heated. ESCA, chemical derivatization and SEM confirmed the successful coating of substrates. It was shown that the covalently attached PAA macromolecules exhibit anti-bacterial characteristics. Samples coated with PAA exposed to a 5 strain mixture of Listeria monocytogenes for 24 hours resulted in 98% decrease in the bacterial population. A mix of three different bacteria, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Escherichia coli was also tested. A reduction of 82 to 96% of bacterial numbers was obtained. Experimental results indicated that double layer structures could also be prepared from PAA-coated surfaces. PAA and poly(vinylpyridine) (PVP) double layers were successfully generated.
Should S Get More Press

This note discusses a problem appropriate for a beginning mathematical statistics course. Four estimators of the standard deviation of a normal data source are compared using mean square error. Both the uniformly minimum variance unbiased estimator and the usual estimator are found to be inadmissible.
[3 + 4] Cycloaddition reactions of vinyl carbenoids with furans

Abstract The rhodium(II) acetate catalysed decomposition of diethyl 4-diazopent-2-enedioate in the presence of furans results in the formation of products derived from a [3 + 4] cycloaddition.
DNA structural alterations in the SV40 enhancer region are retained in vivo.

Abstract Psoralen accessibility in the SV40 regulatory region has been analyzed in vivo on viral minichromosomes and extracellular virus particles using λ psoralen mapping technique which we have recently described. This approach takes advantage of the fact that λ exonuclease digestion of double-stranded DNA is inhibited by the presence of 5-methylisopsoralen monoadducts. Previous analysis of purified restriction fragments from this region irradiated in vitro revealed λ region of psoralen hypersensitivity which encompassed the repeated 72-base-pair (bp) enhancers and sequences 150 by upstream toward the late region. The studies reported here demonstrate that changes in the structure of the DNA helix due to supercoiling do not affect the pattern of psoralen accessibility in this region. Additionally, no significant difference in the precise pattern of the psoralen hypersensitive domain is observed between late nucleoprotein complexes and extracellular virus. Finally, virus particles that have been through λ freezethaw cycle, λ process which we have shown eliminates the preferential photoaddition of the regulatory region in chromatin, also exhibit the same pattern of psoralen hypersensitivity.
“Us Boys like to Read Football and Boy Stuff”: Reading Masculinities, Performing Boyhood

In this qualitative study, I explore how one group of fifth grade African American boys performed masculinity through classroom reading practices. I focus on two aspects of boys' experiences with masculinity: first, how reading practices made visible some of the ways that masculinities were performed in the classroom, particularly how boys defined themselves in relation to each other and to girls; and, second, how boys' performances of masculinity were disrupted through a particular reading experience in which they were required to read texts that they had previously rejected on the basis of gender. Interest in masculinity has recently increased, both in literacy and other humanities and social science fields. Yet, few studies have examined the intersection of masculinity and literacy in classrooms, particularly for boys of color. This study grounds boys' practices of masculinity and reading in recent discussions of masculinity in the popular press and theories of performance, critical and poststructurali...
The fractal shape of riparian forest patches

Remnant patches of a forest corridor were examined along the Iowa and Cedar Rivers, Iowa. A fractal dimension was found for these patches which was incorporated with the perimeter:area ratio in an index of shape. This index was then regressed on 5 hydrogeomorphic variables hypothesized to represent processes which might control patch dimensions, plus a variable to represent human impact. The hydrogeomorphic variables were derived from topographic maps; the impact variable used was the proportion of perimeter that was occupied by a road, railroad, transmission line, urban or other built area, or a straight line judged to be agricultural. Three variables remained significant in a reduced model: human impact, valley width, and stream sinuosity, but together the three accounted for only 24% of the variance in patch shape. The fractal perimeter:area ratio increased with human impact, probably because of reduced area, and decreased with valley width, which allowed more extensive forest on wide floodplains, and with sinuosity, which resulted in small patches isolated on the interior of meanders. These results indicate that in this landscape the hydrogeomorphic structures play a role, but that human impact is more significant in its effect on the shape of remnant forest patches. Other structures, such as the regional topography, may account for the unexplained variance. The index of shape used here may be useful as an independent variable in studies of ecological processes affected by patch shape and form and as a guide to conservation.
Dexamethasone Increases Expression of 5‐Lipoxygenase and its Activating Protein in Human Monocytes and THP‐1 Cells

The aim of this study was to assess the effect of dexamethasone on 5-lipoxygenase pathway expression in human peripheral blood monocytes and the acute monocytic leukemia cell line, THP-1. Cells were conditioned over a period of days with dexamethasone, at concentrations relevant in vivo, to study the effect of the glucocorticoid on calcium-ionophore-stimulated 5-lipoxygenase product and arachidonic acid release. The effect of dexamethasone on levels of immunoreactive protein and steady-state messenger RNA encoding for 5-lipoxygenase and its activating protein (5-LAP) was also assessed. Dexamethasone increased the stimulated release of 5-lipoxygenase products from both monocytes and THP-1 cells in a dose-dependent fashion. The increase in product generation was not due to changes in the availability of arachidonic acid. However, immunoreactive protein and steady-state messenger RNA encoding for 5-lipoxygenase and 5-LAP were increased by conditioning with dexamethasone. There was no apparent effect of the glucocorticoid on LTA4-hydrolase-immunoreactive protein levels or specific activity. We conclude that dexamethasone increases 5-lipoxygenase pathway expression in both monocytes and in THP-1 cells. This effect is due, at least in part, to increases in immunoreactive protein and steady-state messenger RNA encoding for 5-lipoxygenase and 5-LAP. These results suggest a role for glucocorticoids in the regulation of 5-lipoxygenase pathway expression in mononuclear phagocytes.
Summarizing multimodal documents in popular media for people with visual impairments

People without visual impairments often skim a document and look at the graphics it contains before deciding whether to read it in detail. While this is easy for sighted people, it is far more challenging for people with visual impairments, especially since the graphical content is largely inaccessible. We propose to increase the universal accessibility of articles in popular media containing both text and graphical elements for people with visual impairments by automatically generating an abstractive summary of the entire multimodal document. Our goal is to enable users to quickly access the high-level content of a multimodal document, and to decide whether to commit to reading the full article.
Kinetic Monte Carlo study of the effect of hydrogen on the two-dimensional epitaxial growth of Ni(100)

The effects of hydrogen on Ni~100! submonolayer homoepitaxy have been investigated by kinetic Monto Carlo ~KMC! simulations of the Ni growth process with and without the presence of a small hydrogen impurity. The two-dimensional KMC simulations are based upon rate constants for a set of uncorrelated Ni site-to-site hopping mobilities with and without the presence of hydrogen atoms which are found to act as a catalyst. The rate constant activation energies are determined by classical-potential total-energy calculations with semiclassical zero-point energy corrections for the hydrogen atom. This set of KMC simulations extends preliminary work on the activation energies which were reported along with their connection to available experiments in Ref. 1. We find that fast diffusion of H atoms occurs on the flat Ni~100! surface and the presence of these highly mobile H atoms is found to have significant effects on the mobility of lone Ni adatoms, and therefore also on the Ni islands which form during the epitaxial growth. The H atoms increase the mobility of lone Ni adatoms across the flat Ni~100! terrace by stabilizing the transition state for site-to-site hopping of the Ni adatom. While the effects of the H atom on the Ni mobility are primarily catalytic, the kinetically determined Ni island morphologies differ substantially as a function of H atom concentration over time periods which are long on the deposition time scale, and therefore the morphology differences can become frozen in place. Even quite low H atom coverage, by acting to increase lone Ni atom mobility, tends to decrease Ni island density which results in a corresponding increase in the average Ni island size. This suggests that the H atoms are acting as an antisurfactant in the Ni~100! homoepitaxy at low H coverage. @S0163-1829~99!06339-0#
Spatially-encoded far-field representations for interactive walkthroughs

We introduce the notion of spatially encoded video and use it for efficiently representing image-based impostors for interactive walkthroughs. As part of a pre-process, we automatically decompose the model and compute the far-fields. The resulting texture images are organized along multiple dimensions and can be accessed in a user-steered order at interactive rates. Our encoding algorithm can compress the impostors size by two orders of magnitude. Furthermore, the storage cost for additional impostors or samples grows sub-linearly. The resulting system has been applied to a complex CAD environment composed of 13 million triangles. We are able to render it at interactive rates on a PC with little loss in image quality.
Navier-Stokes analysis of muzzle-blast-type waves

A Navier-Stokes solution is presented as a mathematical model to muzzle-blast-type waves. The study has two novel features. First, it is a combined internal/external analysis relating barrel flow parameters to muzzle environment parameters. Second, the dissipative and dispersive effects of viscosity on the propagation phenomenon are captured. The investigation also serves as a numerical analysis of axisymmetric, high-pressure waves in an unsteady, viscous flow. Conservation-form Navier-Stokes equations are integrated by a two-step, explicit finite-difference scheme. The shocks are captured and treated by the inclusion of artificial dissipative terms. Turbulence is accounted for by an algebraic eddy-viscosity model. The internal flow is solved by a predictor-corrector method of characteristics with the shock fitted in; its results compare very well with the experimental data available. The numerical results obtained simulate the muzzle blast waves and show the effects of viscosity. Comparison with the classical spherical blast wave theory shows the deviation in propagation patterns of the axisymmetric and spherical waves. 21 references.
The spectrum of the locked state for the Kuramoto model of coupled oscillators

We analyze the linear stability of the phase-locked state in the Kuramoto model of coupled oscillators. The main result is the first rigorous characterization of the spectrum and its associated eigenvectors, for any finite number of oscillators. All but two of the eigenvalues are negative, and merge into a continuous spectrum as the number of oscillators tends to infinity. One eigenvalue is always zero, by rotational invariance. The final eigenvalue, corresponding to a collective mode, determines the stability of the locked state.
Development of a dual-label time-resolved fluorometric immunoassay for the simultaneous detection of two recombinant proteins in potato.

Immunological methods such as ELISA have been traditionally employed to quantify protein levels in plants improved through modern biotechnology. Combined trait products (i.e., plants producing multiple recombinant proteins) created by introducing multiple genetic traits by transformation or traditional breeding methods have prompted the need for the development of analytical assay technologies capable of detecting and quantifying multiple proteins in a single assay. The development of a two-site, sandwich, dual-label, time-resolved fluorometry-based immunoassay (TRFIA) capable of simultaneously quantitating two recombinant proteins (CP4 EPSPS and Cry3A) in plant sample extracts of genetically improved potato cultivars is reported here. The performance characteristics of TRFIA were similar to or exceeded those of current ELISA methods used to detect and quantitate these proteins. TRFIA is a practical and reliable assay for the quantitation of proteins in genetically improved potato plants and offers an alternative approach to conventional ELISA methods with the added benefit of multiple analyte detection.
Surgical treatment of atherosclerotic heart disease

Because the surgical mortality rate in patients older than age 70 years is significantly higher than that of patients aged 50 to 60 years, surgical treatment of atherosclerosis in the elderly should be used after medical measures have failed. Balloon angioplasty is the surgical treatment of choice, but coronary artery bypass may be performed when necessary. In most patients older than 65 years, the rate of progression of atherosclerosis is slow, and additional surgical treatment may not be required for many years. In the elderly, atherosclerosis is often found in more than 1 of the 4 major arterial beds. About 15% of patients with coronary artery disease requiring operation have atherosclerosis in a second major arterial bed. Previously unpublished data on risk factors and survival rates in patients who have undergone coronary artery bypass surgery are reviewed.
Stripe as an effective one-dimensional band of composite excitations

The microscopic structure of a charge stripe in an antiferromagnetic insulator is studied within the ${t\ensuremath{-}J}_{z}$ model using analytical and numerical approaches. We demonstrate that a stripe in an antiferromagnet should be viewed as a system of composite holon-spin-polaron excitations condensed at the self-induced antiphase domain wall (ADW) of the antiferromagnetic spins. The properties of such excitations are studied in detail with numerical and analytical results for various quantities being in very close agreement. A picture of the stripe as an effective one-dimensional (1D) band of such excitations is also in very good agreement with numerical data. These results emphasize the primary role of kinetic energy in favoring the stripe as a ground state. A comparative analysis suggests the effect of pairing and collective meandering on the energetics of the stripe formation to be secondary. The implications of this microscopic picture of fermions bound to the 1D antiferromagnetic ADW for the effective theories of the stripe phase in the cuprates are discussed.
RNA leaching of transcription factors disrupts transcription in myotonic dystrophy.

Myotonic dystrophy type 1 (DM1) is caused by a CUGn expansion (n ≈ 50 to 5000) in the 3′ untranslated region of the mRNA of the DM protein kinase gene. We show that mutant RNA binds and sequesters transcription factors (TFs), with up to 90% depletion of selected TFs from active chromatin. Diverse genes are consequently reduced in expression, including the ion transporter CIC-1, which has been implicated in myotonia. When TF specificity protein 1 (Sp1) was overexpressed in DM1-affected cells, low levels of messenger RNA for CIC-1 were restored to normal. Transcription factor leaching from chromatin by mutant RNA provides a potentially unifying pathomechanistic explanation for this disease.
Cannabinoid-1 receptor gene deletion has a compartment-specific affect on the dendritic and axonal availability of μ-opioid receptors and on dopamine axons in the mouse nucleus accumbens.

Cannabinoid-type 1 (CB1) receptors are implicated in mu-opioid receptor (mu-OR)-dependent reward ascribed partially to mesolimbic dopamine release in the nucleus accumbens (Acb) shell. Thus, CB1 receptor gene deletion may preferentially alter the availability of mu-ORs and/or dopamine innervation in this brain region, which is functionally distinct from the motor-associated Acb core. To test this hypothesis, we examined the electron microscopic immunolabeling of the mu-OR and the dopamine-synthesizing enzyme, tyrosine hydroxylase (TH) in Acb shell and core of adult C57BL/6J wild-type (WT) and CB1-knock-out (KO) mice. The mu-OR-immunogold particles were observed in the cytoplasm and on the plasmalemma in dendrites, dendritic spines, and axon terminals throughout the Acb. Compared with WT, the Acb shell of CB1-KO mice showed a lower cytoplasmic density of mu-ORs in dendrites, and fewer mu-OR labeled, but not unlabeled, dendritic spines. In this region, the CB1-KO’s had a significantly enhanced plasmalemmal density of mu-OR-immunogold in axon terminals, 70% of which formed excitatory-type synapses. However, the number of both mu-OR-labeled terminals and TH-labeled small varicosities was significantly reduced in the Acb shell of CB1-KO’s. These adaptations were not seen in the Acb core, where CB1-KO’s had a preferentially lower dendritic plasmalemmal and total spine density of mu-OR immunogold. Our results indicate that constitutive deletion of the CB1 receptor gene has a major impact on the pre- and post-synaptic availability of mu-ORs at axospinous synapses and on the dopamine innervation of the Acb shell, as well as the dendritic surface expression of mu-ORs in Acb core of mature rodents.
Immunologic development early in life following severe respiratory syncytial virus (RSV) bronchiolitis

Abstract Rationale Immune response following viral infection usually involves Th1-mediated response; however, severe RSV appears to be associated with the development of asthma, a Th2 phenotype. Therefore, we sought to understand the early immunologic response to the first RSV infection in a prospectively enrolled study of 206 hospitalized infants in the RSV Bronchiolitis in Early Life (RBEL) cohort (follow-up 2.7 ± 1.1 yr). Methods Peripheral blood T cells were obtained from these children immediately following RSV infection and two years later, incubated with PMA/ionomycin, permeabilized, labeled with anti-CD3 and intracellular anti-cytokine mAb and analyzed by flow cytometry. In addition, RNA, from a subset of these children's T cells, was analyzed by real time PCR for these same cytokines. Results To date 82 (40%) RBEL children have developed asthma diagnosed by a physician. Using both methods, we found significant increase in interleukin (IL)-2, 13 and interferon-g (IFN-g) levels and decrease in IL-4/IFN-g ratio over two years (all P Conclusions RSV infection appears to induce a Th2 immune response early in life which may be predictive of the subsequent development of asthma. Further longitudinal studies in the RBEL cohort are needed to substantiate these findings.
The Impact of Personal Identity on Advance Directives

Advance directives record our voluntary choices and provide guidelines for people making decisions on our behalf when we are no longer capable of making substantiated, reasoned choices for ourselves. In some circumstances, especially when no curative treatments are available, prior wishes for a painless, quick, and dignified end of life are the last bellowing of autonomy. In other cases, however, respecting the advance directive is not the right answer. When large shifts in psychology have resulted from illness, and autonomy cannot be restored, prior wishes may become obsolete. Therefore, a new conceptual framework for adjudicating the applicability of advance directives is needed.
Animal fat feedstocks for oleochemicals

Inedible tallow is a major raw material source in the manufacture of fatty acids and hence in the production of oleochemicals. The U.S. generates about 55% of the world’s total tallow production of six million metric tons, but supplies about 80% of the tallow imported by other countries. U.S. inedible tallow and grease usually is a blend whose principal component is rendered beef fat. It consistently has been and still is the least expensive of the various fats and oils and is traded in various grades depending on physical characteristics.
Fatal pancreatitis as a complication of therapy for HIV infection

Abstract Acute pancreatitis in HIV-infected patients with or without AIDS has been reported with increasing frequency over the past several years. Drugs used to treat HIV-infected patients are often the cause. We report a case of a 46-year-old HIV-infected man who presented to the emergency department with abdominal pain and was diagnosed with acute pancreatitis. The patient had recently begun taking 2′,3′-dideoxyinosine (ddI). He died shortly after admission to the hospital; CT scan and autopsy confirmed the cause of death as hemorrhagic pancreatitis. We briefly review the literature on the incidence and severity of pancreatitis in association with ddI and pentamidine therapy.
Sources of speciated atmospheric mercury at a residential neighborhood impacted by industrial sources.

Speciated measurements of atmospheric mercury plumes were obtained at an industrially impacted residential area of East St. Louis, IL. These plumes were found to result in extremely high mercury concentrations at ground level that were composed of a wide distribution of mercury species. Ground level concentrations as high as 235 ng m{sup -3} for elemental mercury (Hg{sup 0}) and 38,300 pg m{sup -3} for reactive mercury species (reactive gaseous (RGM) plus particulate (PHg) mercury) were measured. The highest mercury concentrations observed during the study were associated with plumes that contained high concentrations of all mercury species (Hg{sup 0}, RGM, and PHg) and originated from a source located southwest of the sampling site. Variations in proportions of Hg{sup 0}/RGM/PHg among plumes, with Hg{sup 0} dominating some plumes and RGM and/or PHg dominating others, were attributed to differences in emissions from different sources. Correlations between mercury plumes and elevated NOx were not observed; however, a correlation between elevated SO{sub 2} and mercury plumes was observed during some but not all plume events. Despite the presence of six coal-fired power plants within 60 km of the study site, wind direction data along with Hg/SO{sub 2} and Hg/NOx ratios suggest that high-concentration mercury plumesmore » impacting the St. Louis-Midwest Particle Matter Supersite are attributable to local point sources within 5 km of the site. 35 refs., 5 figs.« less
The interaction of liposomal amphotericin B and serum lipoproteins within the biological milieu.

AbstractPreviously, we have shown that liposomal amphotericin B (L-AmpB) is less nephrotoxic than and equally as effective as free AmpB as treatment of patients with systemic fungal infections; The mechanism of L-AmpB's enhanced therapeutic index, however, remains unknown. This review discusses AmpB's association with lipoproteins, predominantly high-density lipoproteins (HDL) and the biological relevance of transferring AmpB to HDL. We observed that AmpB was less toxic to pig kidney cells when associated with HDL but still remains toxic when associated with low-density lipoproteins (LDL). AmpB's association with HDL or LDL does not alter its antifungal activity. We further found that these kidney cells express high- and low-affinity LDL receptors but only low-affinity HDL receptors. The reduced renal cytotoxicity of HDL-associated AmpB may be due to its lack of interaction with the renal cells, since they have no HDL receptors. Since AmpB interacts with cholesteryl esters in serum, whose transfer between...
Supramolecule-to-supramolecule transformations of coordination-driven self-assembled polygons.

Two types of supramolecular transformations, wherein a self-assembled Pt(II)-pyridyl metal−organic polygon is controllably converted into an alternative polygon, have been achieved through the reaction between cobalt carbonyl and the acetylene moiety of a dipyridyl donor ligand. A [6 + 6] hexagon is transformed into two [3 + 3] hexagons, and a triangle−square mixture is converted into [2 + 2] rhomboids. 1H and 31P NMR spectra are used to track the transformation process and evaluate the yield of new self-assembled polygons. Such transformed species are identified by electrospray ionization (ESI) mass spectrometry. This new kind of supramolecule-to-supramolecule transformations provides a viable means for constructing, and then converting, new self-assembled polygons.
Coronary heart disease mortality/morbidity and risk in blacks. II: Access to medical care

Abstract Since the cardiovascular disease mortality is higher, life expectancy shorter, and socioeconomic conditions lower for black persons compared to the majority population, speculation arises as to the possible role of distribution of health resources for this segment of the population. Data from the City of Los Angeles, collected by health districts allowing the parallel use of census tract data, confirm that deaths caused by ischemic heart disease occur at a lower age in blacks and that a dramatic fall in these rates (which are lower than for the majority population) has not occurred during the 1970–1979 period. Observations on some relevant factors and suggestions for further monitoring of health care needs and resources are offered.