cssi/SciSciGPT-SciSciNet huggingface dataset:
Cerebral Blood Flow Velocity and Task Engagement as Predictors of Vigilance Performance

Responses to a brief six-min screening battery involving high-workload tracking, verbal working memory, and line discrimination tasks were used to predict subsequent performance on a 36-min vigilance task. Two predictors of interest were subjective state, as indexed by the Dundee Stress State Questionnaire (DSSQ), and cerebral blood flow velocity (CBFV), measured via transcranial Doppler sonography. The results testify to the importance of assessing task-induced responses for predicting vigilance performance. They also indicate that forecasting vigilance performance is a complex endeavor requiring a set of multidimensional predictors. Specifically, higher post-battery task engagement scores on the DSSQ in this study and higher levels of CBFV in the left hemisphere during performance of the screening battery predicted more correct detections on the subsequent vigilance task. These findings are interpreted in the light of the resource-workload model of vigilance, and their practical significance is discussed.
Chemokines in multiple myeloma.

Objective In this article we focus on the role that chemokines and chemokine receptors play in the pathogenesis of multiple myeloma and the associated bone destructive process, and consider their utility as novel therapeutic targets for treating this devastating disease. Methods Current research on the role that chemokine and chemokine receptors play in the pathogenesis of myeloma is reviewed. Results The chemokines, MIP-1α, MCP-1, IL-8, and SDF-1, and their receptors play important roles in homing of MM cells, tumor growth, and bone destruction in myeloma. They are attractive therapeutic targets for treating myeloma patients. Conclusion Addition of chemokine antagonists to current treatment regimens for myeloma should result in better therapeutic responses because of the loss of both the protective effect of the marrow microenvironment on the MM cells and the induction of osteoclast activity.
Abstract 2290: Human gut microbiome and risk of colorectal cancer, a case-control study.

Introduction: Inflammatory responses play a decisive role in colorectal cancer etiology, yet specific causes remain unclear. Our hypothesis is that gut microbial alterations promote colorectal carcinogenesis, possibly through inflammation. To test this hypothesis, we conducted a case-control study of the gut microbiome in 47 histologically confirmed colorectal cancer cases and 94 non-cancer controls (matched by gender and body mass index) who were previously recruited (Schiffman et al, 1989). Demographic and clinical information was assessed by questionnaire and medical chart review, and lyophilized fecal biospecimens for gut microbiome analysis were obtained before initiation of any treatment. Methods: Ribosomal 16S rRNA genes in fecal DNA were amplified by universal primers, bar coded and sequenced by 454 FLX technology. 16S rRNA bacterial gene sequences were binned into operational taxonomic units (OTUs) with 97% identity and aligned to fully sequenced microbial genomes (IMG/GG GreenGenes) in the QIIME pipeline. We performed t-tests and nonparametric Wilcoxon signed-rank tests to compare differences between colorectal cancer cases than controls on alpha diversity (Shannon9s diversity index) and relative abundance of specific taxa, respectively, unadjusted for multiple comparisons. Results: From 141 fecal samples, we have obtained 794,217 16S rRNA gene sequence reads. Shannon9s diversity index was significantly lower in cases (p=0.02; 7.86 for cases; 8.33 for controls). In taxonomy-based analyses, Fusobacterium genus was significantly enriched in the colorectal cancer cases compared with control group (p=0.003). Relative abundance of Fusobacterium sequences ranged from 0-28.9% in cases (median 0.072%) compared to 0-1.3% in controls (median 0.027%). We also noted a relative decrease in abundance of Clostridia (p=0.01, class) and Actinobacteria (p=0.03, phylum) in the colorectal cancer group compared with controls. Conclusion: This first study of the gut microbiome in colorectal cancer patients compared with non-cancer controls suggests that the differential abundances in stool of Fusobacteria, and possibly Clostridia and Actinobacteria, are associated with risk of colorectal cancer. Consistent with our results, two recent studies reported that Fusobacterium sequences were enriched in human colorectal tumor tissue compared to adjacent normal tissue (Kostic et al, 2012 and Castellarin et al, 2012). Fusobacterium is an anaerobic, Gram-negative bacteria, with invasive and proinflammatory characteristics through lipopolysaccharides. Further study is needed to define its role in colorectal carcinogenesis. Citation Format: Jiyoung Ahn, Rashmi Sinha, Zhiheng Pei, Christine Dominianni, James J. Goedert, Richard B. Hayes, Liying Yang. Human gut microbiome and risk of colorectal cancer, a case-control study. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2290. doi:10.1158/1538-7445.AM2013-2290
Surface analysis algorithms for scanning probe microscopy

Abstract A single data set in scanning probe microscopy is large, typically in the megabyte range. As interpretation is accomplished by displaying the data in image form for visualization, image processing methods are used to both convert to visual images and to modify the images in order to clarify features of interest. Although an impressive number of image-processing algorithms are available on most commercial probe microscopes, many potentially very interesting ones are not. In addition, the special character of scanning probe data sets calls for development of new algorithms specially suited to this kind of problem. The work here analyzes images produced using atomic force microscope data sets. Algorithms are shown and discussed using images of oxide surfaces. The following algorithms are applied: tilt correction, scattering noise removal, surface smoothing, surface compression, probability density function analysis, correlation, and power spectrum analysis. Such algorithms and others serve to remove spurious surface spikes, enhance visualization of long-range surface features in the presence of short-range surface variations, remove line-to-line scanning artifacts, etc.
Sex as a Status Variable in Work Settings: Female and Male Reports of Dominance Behavior

This study shows that sex is an important status variable in occupational settings. The basic hypothesis that males, because of a status prerogative, would be more likely than females to use nonverbal and verbal dominance behaviors, including intimate gestures, toward their opposite sex co-workers was confirmed. Subjects (88 female and 69 male samples from two institutions of higher learning) reported dominance behaviors (a) toward opposite sex co-workers; (b) from opposite sex co-workers; (c) toward opposite sex superiors; and (d) from opposite sex superiors. Analysis of the sexual dominance items revealed that sexual intimacy is expressable along the same continuum as traditional dominance gestures. The hypothesis that sex competes with other status variables was supported. If the sexual dominance patterns explored in this study prove widespread, institutions may wish to provide programs aimed at raising employee awareness of these interactions.
Climate-related differences in zooplankton density and growth on the inner shelf of the southeastern Bering Sea

Abstract Zooplankton abundance and biomass were measured during spring and late summer on the inner shelf of the southeastern Bering Sea in years of climate extremes. Samples were taken during late spring and late summer of three years: 1997, a year of moderate spring ice cover and unusually warm, calm summer conditions; 1998, a year of warm, but stormy summer conditions with very little spring ice cover; and 1999, a year of extensive spring ice cover, cold spring conditions and storms during spring and summer. Mean water column temperature was significantly lower during June 1999 than June 1998 and 1997. Copepod abundance and biomass during June were correlated with mean water column temperature and mean temperature below the thermocline. Mean calanoid abundance during June 1999 was 8–52% of the mean abundance during 1998 and 1997. Significantly lower abundances during June 1999 were observed for Calanus marshallae, Acartia spp., Pseudocalanus spp. and calanoid nauplii. Significant interannual differences in mean water column temperature and calanoid abundance during late summer (late July–early September) were not detected. The Hirst–Lampitt equations were used to estimate the mean daily copepod production during the warm and cold years. The mean production estimate during warm conditions was 13 mg C m−2 d−1, with a range of 3–37 mg C m−2 d−1, similar to previous estimates. Production estimates during the cold spring, 1999, were 3–4% of the production during warm periods. Assuming a 35% gross growth efficiency, calanoids could consume an average of 37 mg C m−2 d−1 during warm periods, but only about 2.6 mg C m−2 d−1 during a cold spring. Comparison of the above estimates to concurrent measures of primary production indicate that during warm, calm seasons, calanoids could remove most or all of the available water column primary production, thus indicating that calanoids may have been food limited. During cool conditions, the calanoids could remove only about 3% of the estimated daily primary production. Lower post-bloom primary production rates and higher calanoid grazing rates may result in substantially lower annual carbon flux to benthic communities on the inner shelf during warm calm years relative to cold years with extensive spring ice cover.
The pollen record of a 20th century spruce beetle (Dendroctonus rufipennis) outbreak in a Colorado subalpine forest, USA.

The frequency and intensity of ecosystem disturbance, including outbreaks of forest insects and forest fires, is expected to increase in the future as a result of higher temperatures and prolonged drought. While many studies have concentrated on the future climatic impacts on fire, little is known about the impact of future climate on insect infestation. Paleoecological techniques are important in this regard in identifying the potential relationships between climate and insect outbreaks in the past, as a predictive tool for the future. We examine a high-resolution 20th century record of spruce beetle (Dendroctonus rufipennis) infestation from a small, subalpine lake, comparing the paleoecological record to the historical and tree-ring record of the event. An extensive spruce beetle outbreak occurred in northwestern Colorado during the 1940s and 1950s, causing widespread mortality of mature Picea engelmannii. Pollen analysis of this period documents the decline of Picea and its replacement locally by Abies lasiocarpa, paralleling age and composition studies of modern forest stands in the region. This study is a proof of concept that, when applied to longer sedimentary records, could produce a detailed record of infestation for the Late Holocene or older time periods. This information will be useful to forest managers in efforts to plan for the effects of D. rufipennis infestations, and subsequent succession within high elevation conifer forests.
Metal droplet deposition on non-flat surfaces: effect of substrate morphology

Abstract In droplet-based deposition processes, substrate morphology plays an important role in the bonding quality between splats and substrate. This paper presents a numerical investigation of metal droplet impact and solidification on two types of non-flat surfaces, namely a pre-molten pool and a wavy surface. We solve the axi-symmetric incompressible Navier–Stokes equations and an enthalpy formulation of the energy equation to simulate both the flow field and the heat transfer during droplet spreading and solidification. The results show that for efficient droplet deposition on molten pools, the pool size and droplet impact velocity should be kept relatively small. Droplet impingement on non-flat surfaces is almost always accompanied by splashing. The degree of splashing decreases with the increase in surface roughness height. Increasing surface roughness wavelength improves droplet spreading and hence solidification.
Decoherence of geometric phase gates

We consider the effects of certain forms of decoherence applied to both adiabatic and nonadiabatic geometric phase quantum gates. For a single qubit we illustrate path-dependent sensitivity to anisotropic noise and for two qubits we quantify the loss of entanglement as a function of decoherence.
A new hypothesis to explain stability of borehole breakouts

Abstract Borehole breakouts are elliptical-like holes caused by unequal insitu stresses during the drilling of oil and gas wells. This paper presents a new model for studying the mechanics of borehole breakouts. This model includes analysis of the initial breakout, and a proposed procedure for determining stability of subsequent breakout configurations. The motivation of the present work is to provide a theoretical basis for computing in situ stress magnitudes from breakout size and shape measurements. Applications would be the use of caliper logs or downhole TV measurements of breakout features to provide an inexpensive tool for estimating insitu stresses. The question that motivated this work was, “How can a breakout become stable when elasticity analysis predicts greater failures with increasing ellipticity?” This paper attemps to provide a framework to answer this question.
The facilitating effects of various training methods on the development of verbal control of nonverbal behavior in four-year-old children

This study investigated the effects of passive movement and imitation training with verbal instructions on the learning of a perceptual-motor task and the effects of these training procedures on the children’s behavior when the perceptual-motor associations formed in the initial learning are reversed under adult verbal instructions. The four treatments were passive movements and imitation with and without verbal instructions. The conditions were a two-association (colors-forms) motor-perceptual task and the reversal of the associations by means of verbal instructions. The results indicated that 4-year-olds performed significantly better on both task conditions when training was accompanied by verbal instructions. The results indicated that the development of verbal control of nonverbal behavior may be manipulated and develooed artificially.
The design, implementation, and evaluation of a symmetric banded linear solver for distributed-memory parallel computers

This article describes the design, implementation, and evaluation of a parallel algorithm for the Cholesky factorization of symmetric banded matrices. The algorithm is part of IBM's parallel engineering and scientific subroutine library version 1.2 and is compatible with ScaLAPACK's banded solver. Analysis, as well as experiments on an IBM SP2 distributed-memory parallel computer, shows that the algorithm efficiently factors banded matrices with wide bandwidth. For example, a 31-mode SP2 factors a large matrix more than 16 times faster than a single node would factor it using the best sequential algorithm, and more than 20 times faster than a single node would using LAPACK's DPBTRF. The algorithm uses novel ideas in the area of distributed dense-matrix computations that include the use of a dynamic schedule for a blocked systolic-like algorithm and the separation of the input and output layouts from the layout the algorithm uses internally. The algorithm alson uses known techniques such as blocking to improve its communication-to-computation ratio and its data-cache behavior.
Inelastic tunnelling and the pair-quasiparticle interference current in Josephson junctions

Abstract The contribution to the quasiparticle current and pair—quasiparticle interference current of inelastic tunnelling due to the excitation of a boson mode in the tunnelling barrier is evaluated.
Association between residual mitral regurgitation and left ventricular outflow obstruction after carpentier ring mitral annuloplasty

In 1971, Carpentier et al1 reported the use of a new technique for mitral valve repair using an annuloplasty ring. Although this technique avoids some complications of prosthetic valves, spatial changes in the mitral apparatus after this operation may result in systolic anterior motion of the mitral valve which may cause left ventricular (LV) outflow obstruction similar to that seen in hypertrophic cardiomyopathy.2,3 In a series of 439 patients, systolic anterior motion was seen in 6.4% of patients after Carpentier ring repair, and LV outflow obstruction was present in 2.3%.4 Although outflow obstruction may be treated successfully medically,4 it may also be a cause of immediate (intraoperative) failure of the technique.5 We have previously reported a relation between mitral regurgitation (MR) and LV outflow obstruction in 2 groups. In those who have undergone aortic valve replacement for aortic stenosis, the relief of outflow obstruction after aortic valve replacement was associated with a significant reduction in the degree of MR.6 In the second group, those with hypertrophic cardiomyopathy, the degree of MR was directly associated with the severity of outflow obstruction.7 The current study evaluates the possible mechanisms of LV outflow obstruction after Carpentier ring mitral annuloplasty, and investigates the relation, if any, of MR to the presence of LV outflow obstruction.
Combustion Synthesis of a Porous Layer

Abstract-We consider a model of filtration combustion in a thin porous layer immersed in a bath of gaseous oxidizer. which provides for exchange of the oxidizer between the pores and the bath. We employ approximate analytical methods to derive explicit analytical expressions for various quantities associated with uniformly propagating solutions, including the combustion temperature, the propagation velocity, and the final depth of conversion, as well as results about the structure of the solution. We also employ numerical computation to find profiles for the reaction rate, temperature. pressure, density and depth of conversion, as well as to determine the stability of the solutions as a function of various parameters. We identify a new pulsating instability associated with gas mass transfer between the pores and the bath, and describe the mechanism of pulsations.
A Dynamic LES Scheme for the Vorticity Transport Equation

This work aims at the development of a Lagrangian large eddy simulation (LES) scheme. The scheme is based on the filtered vorticity transport equation and on modeling the effects of subfilter scale (SFS) velocity and vorticity fluctuations using a dynamic eddy diffusivity model. The dynamic implementation of the model relies on multiple filtering in order to determine model coefficients from the resolved data. The performance of the dynamic SFS model is examined usinga prioritests that are based on direct numerical simulations of forced, homogeneous, isotropic turbulence. The tests show a fair correlation of the model with SFS convection of vorticity. In addition, the computed value of the dynamic model coefficient is in good agreement with predictions based on enstrophy balances. Finally, the direct numerical simulation data is used to compare a three-dimensional particle representation of the model with spectral evaluations. The tests show that when the particle representation is sufficiently resolved, the Lagrangian model predictions are in good agreement with spectral results.
Confirmatory Factor Analysis of the WISC-IV in a Hospital Referral Sample

Confirmatory factor analysis was used to determine the factor structure of the Wechsler Intelligence Scale for Children–Fourth Edition (WISC-IV) scores of 297 children referred to a children’s hospital in the Southwestern United States. Results support previous findings that indicate the WISC-IV is best represented by a direct hierarchical (bifactor) model including four first-order factors and one general intelligence factor. In this sample, the general intelligence factor accounted for 50% of the total variance and 76% of the common variance. Of the firstorder factors, the Verbal Comprehension factor accounted for the most total (5.6%) and common (8.4%) variance. Furthermore, the general intelligence factor accounted for more variance in each subtest than did its respective first-order factor and it was the only factor that exhibited adequate measurement precision (ω h = .87). These findings support previous recommendations that WISC-IV interpretations should focus on the general intelligence factor over first-order factors.
Spectrum of Volume Relaxation Times in B2O3

Time-index of refraction isotherms were measured for B2O3 glass starting from both a high and a low temperature in the transformation region. The equilibrium index values at each temperature, obtained from both types of approach curve, were identical. As in the case of the density values, the equilibrium refractive index curve as a function of temperature for this glass is not a straight line. The two-relaxation-times (crossover) model was applied to B2O3 glass and fitted the data as well as it did in previous experiments with borosilicate crown and GeO2 glasses. The reverse crossover which was predicted by the model was experimentally confirmed with the B2O3 glass. The spectrum of relaxation times narrowed with decreasing temperature, indicating approach to another region of single relaxation associated with the low-temperature Arrhenius region. The relaxation times for the low-temperature crossover agreed well with those from the high-temperature curves, indicating complete linearity in the experiments. The spectrum of relaxation times was slightly asymmetrical at constant pressure and very asymmetrical at constant volume.
The radiologic features of myotonic dystrophy with presentation of a new finding.

The many radiological features associated with myotonic dystrophy have been described with some emphasis placed on a possible new finding of diffuse narrowing of the sigmoid colon. Although most major changes in this disease are caused by a generalized muscular atrophy, an explanation to account for the sigmoid narrowing cannot be fully established at this time. The radiologist should be aware of all the existing features in this disease in order to avoid implicating other disorders to account for the findings.
Multi-Attribute Seismic Volume Facies Classification for Predicting Fractures in Carbonate Reservoirs

Poststack seismic attributes are beginning to be routinely utilized in the analysis of 3D seismic data for both reservoir development and exploration targets. In addition to conventional geologic and engineering data, seismic attributes can provide valuable insight into how carbonate reservoirs are fractured. Optimized oil production in one prolific Jurassic carbonate reservoir in Saudi Arabia can be affected by fracturing (Pham and Ali, 2003). Proper reservoir management considers that reservoir fluids move differentially along these natural migration pathways. The detailed and accurate mapping of the distribution and extent of these fractures is important for reservoir management. New types of seismic volumetric attributes and better integration of geophysical, geologic, borehole, and engineering data are being adopted to meet this challenge. Volumetric seismic attributes computed from 3D seismic data are being used to map and interpret small faults and fractures that may affect fluid flow. These fractu...
Single-spin superconductivity: Formulation and Ginzburg-Landau theory

We describe a superconducting phase that arises due to a pairing instability of the half-metallic antiferromagnetic (HM AFM) normal state. This single-spin superconducting (SSS) phase contains broken time-reversal symmetry in addition to broken gauge symmetry, the former due to the underlying magnetic order in the normal state. A classification of normal-state symmetries leads to the conclusion that the HM AFM normal phase whose point group contains the inversion operator contains the least symmetry possible which still allows for a zero momentum pairing instability. The Ginzburg-Landau free energy for the superconducting order parameter is constructed consistent with the symmetry of the normal phase, electromagnetic gauge invariance and the crystallographic point-group symmetry including inversion. For cubic, hexagonal, and tetragonal point groups, the possible symmetries of the superconducting phase are classified, and the free energy is used to construct a generalized phase diagram. We identify the leading candidate out of the possible SSS phases for each point group. The symmetry of the superconducting phase is used to determine the cases where the gap function has generic zeros (point or line nodes) on the Fermi surface. Such nodes always occur, hence thermodynamic properties will have power-law behavior at low temperature. {copyright} {ital 1998} {italmore » The American Physical Society}« less
Fire load: Survey data, recent standards, and probabilistic models for office buildings

Abstract To enable a probabilistic performance-based approach to fire design, probabilistic models to represent the fire load are needed. Such probabilistic models are presented in this paper for office buildings. First, a literature review of recent fire load density surveys is presented. These surveys indicate a large range of fire load density values, and strong correlation between fire load density, compartment area, and use. However, current codes and standards (such as Eurocode and a recent publication of NFPA 557) that are used to estimate fire load density do not account for these variables and specify constant values. Based on survey data, a Bayesian probability approach is used to develop probabilistic models to predict the fire load density in office buildings (one for light-weight use and one for heavy-weight use). The models consider the size of the compartment and the office room use (general office, library, storage, etc.). The proposed models correlate well to the data and have a better fit than that obtained, using the Eurocode and NFPA 557. The proposed models for fire load density are then used to develop probabilistic models for the maximum fire temperature in a given compartment. Several scenarios with different floor areas and openings are defined and the fire load models developed in this paper are used to investigate the range of possible maximum fire temperatures and their corresponding probabilities. It is found that the proposed maximum temperature model results in a range of temperatures that correlates well with the test data and the Refined Tanaka Method proposed by a recent SFPE standard. It is shown that both the fire load density and the maximum temperature probabilistic models are well suited for application in a probabilistic performance-based approach to fire design.
China and the military use of the ocean

Abstract Because of the perception of threat from the sea, military and security concerns have played a major role in the formulation of China's marine policy concerning the military use of the ocean. Throughout the Third UN Conference on the Law of the Sea, China rebuked the superpowers’ position on the right of passage for warships and asked for the incorporation of the requirement of prior notification and authorization into the 1982 UN Convention on the Law of the Sea, although without avail. The perception of external naval threat has also played an important role in the process of developing China's navy over the past three and half decades or so. In recent years, because of the growth of China's maritime activities and the escalation of conflict between China and other coastal states, particularly Vietnam, the importance of the navy as a tool to protect and pursue China's maritime interests has significantly increased.
Stereological analysis of bone architecture in the pig zygomatic arch

An understanding of stress distribution within bones requires three-dimensional information on bone strain and bone material properties. Material properties can be relatively easily obtained by mechanical (Turner and Burr, 1993) or ultrasonic (Ashman et al., 1984; Dechow et al., 1993) techniques for locations that are predominantly cortical. Trabecular bone is more difficult to assess, because the dimensions of the test samples strongly influence measured properties (Linde et al., 1992) and because failure at sample ends biases the overall results (Odgaard et al., 1989). These problems can be overcome if the sample of trabecular bone is large enough to allow strain to be measured specifically from the central section (Ashman et al., 1987; Odgaard et al., 1989; Teng and Herring, 1996). Unfortunately, there are many cancellous areas in the irregularly shaped flat bones of the craniofacial skeleton that are too small for an adequate sample. Moreover, the orientation of the trabeculae can vary greatly between adjacent areas, suggesting that regional differences, which cannot be assessed experimentally, may be of great significance in the overall architecture of the bones. In such cases the best available technique is textural analysis of bone structure using stereological methods (Cowin, 1985; Goldstein, 1992). Such an analysis of the mandibular condyle of the pig (Teng and Herring, 1995) provided an accurate prediction of actual mechanical properties (Teng and Herring, 1996). One location where analysis of trabecular architecture may help to elucidate loading is the zygomatic arch, a construct of two flat bones (zygomatic and squamosal) that are primarily cancellous in growing animals. In addition to providing the origin of the large masseter muscle, the arch mechanically links the tooth-bearing maxilla to the jaw joint and braincase. Loading in the arch is far from simple. A recent in vivo study of strain in the zygomatic arch of the pig (Herring et al., 1996) revealed the surprising finding that the lateral surfaces of the two component bones are deformed to different degrees and in different directions. Specifically, strain magnitudes were substantially higher in the squamosal bone than in the zygomatic, and the axes of the principal strains were rotated approximately 50°. Reasons for this striking variation are not clear. The two bones of the arch may be loaded differently. Specifically, the squamosal bone, but not the zygomatic bone, may be bent out-of-plane such that its lateral surface becomes more convex. Because strain gauges can be installed only on the lateral surface it is difficult to assess out-of-plane bending. Another possibility is that a relatively less dense and more anisotropic architecture of the squamosal bone was responsible for increased and reoriented strain even in the face of the same applied load. The present study on trabecular architecture was undertaken to investigate these possibilities.
Inhibition of crayfish glutamic acid decarboxylase by structural analogs of the substrate and product.

Abstract 1. 1. Crayfish glutamic acid decarboxylase (GAD) is inhibited by some aliphatic carboxylic acid analogs of glutamate and γ-amino- N -butyric acid (GABA). 2. 2. Variations in the length of the carbon skeleton, substitution of a keto for a methylene group, replacement of the carboxyl group or attachment of a bulky basic moiety to the amino terminus of GABA all lead to a drastic reduction in its inhibitory activity. Substitution of a methyl group for the amino group of GABA is a permissible alteration which does not reduce the inhibitory potency. 3. 3. Some structural analogs of glutamate are inhibitory also, particularly if they possess a comparable carbon skeleton and a keto group in the a position or a sulfhydryl group. 4. 4. Most of the sulfhydryl analogs are significantly more potent as inhibitors than the corresponding compounds in which the SH group is replaced by an H atom.
RhoGAP68F controls transport of adhesion proteins in Rab4 endosomes to modulate epithelial morphogenesis of Drosophila leg discs

Abstract Elongation and invagination of epithelial tissues are fundamental developmental processes that contribute to the morphogenesis of embryonic and adult structures and are dependent on coordinated remodeling of cell–cell contacts. The morphogenesis of Drosophila leg imaginal discs depends on extensive remodeling of cell contacts and thus provides a useful system with which to investigate the underlying mechanisms. The small Rho GTPase regulator RhoGAP68F has been previously implicated in leg morphogenesis. It consists of on an N-terminal Sec14 domain and a C-terminal GAP domain. Here we examined the molecular function and role of RhoGAP68F in epithelial remodeling. We find that depletion of RhoGAP68F impairs epithelial remodeling from a pseudostratified to simple, while overexpression of RhoGAP68F causes tears of lateral cell–cell contacts and thus impairs epithelial integrity. We show that the RhoGAP68F protein localizes to Rab4 recycling endosomes and forms a complex with the Rab4 protein. The Sec14 domain is sufficient for localizing to Rab4 endosomes, while the activity of the GAP domain is dispensable. RhoGAP68F, in turn, inhibits the scission and movement of Rab4 endosomes involved in transport the adhesion proteins Fasciclin3 and E-cadherin back to cell–cell contacts. Expression of RhoGAP68F is upregulated during prepupal development suggesting that RhoGAP68F decreases the transport of key adhesion proteins to the cell surface during this developmental stage to decrease the strength of adhesive cell–cell contacts and thereby facilitate epithelial remodeling and leg morphogenesis.
Validity of pulmonary artery catheter-derived hemodynamic information during bronchopulmonary lavage

Critical Care Systems, Chicago, IL), and urine output. For the left BPL, the position of the PAC in the fight pulmonary artery (PA) was confirmed fluoroscopically. For the right BPL, the position of the PAC in the right PA was confirmed by TEE (Two-Dimensional Orrmiplane, Hewlett-Packard, Andover, MA). After placing the patient in a slight lateral decubitus position (ie, left decubitus-left lung lavage, right decubitus-right lung lavage), the lung undergoing lavage was "degassed" by clamping the appropriate lumen of the endobronchial tube for 5 minutes. The nonlavaged lung was ventilated with a tidal volume of approximately 10 mL/kg, F102 of 1.0, inspiratory pressure (plateau) of 35 cmH20, and respiratory rate aimed at maintenance of end-tidal CO2 of 35 to 40 mmHg. Lavage was initiated with 0.9% saline solution warmed to 37.0°C, optimized by chest percussion, and instilled from a height approximately 30 cm above the midaxillary line. The fluid drained to a collection reservoir at ground level passively by gravity through a Y-piece in the tubing. For the left BPL, 17 L of 0.9% saline were lavaged until the lavage effluent was almost clear, whereas the right BPL required 9 liters. Mean arterial pressure (MAP) was maintained above 80 mmHg during lavage by alteration of depth of isoflurane and administration of crystalloid, as necessary. During both left and right BPL, PAC-derived hemodynamic data were recorded for three lavage cycles; namely, on completion of the lung filling and emptying. The thermodilution method was used to measure CO, which was obtained by calculation of the mean of two saline (room temperature)
Photon-induced X-ray Fluorescence Analysis of Plain Brasses

An x-ray spectrometric method, using a radioisotopic radiation source, for analyzing plain brasses (binary copper-zinc alloys) has been developed. The alloys are analyzed as such without dissolving them in any solvent. Methods to correct the contribution due to CuKβ to the ZnKβ intensity, the difference in fluorescent intensity of the two elements under consideration, and the dead time loss are discussed. The configuration of the system is given. The results obtained by the above method are compared with those obtained using atomic absorption spectrometry and with the certified values.
Ion beam imprinting system

An ion beam imprinting system has been developed at Lawrence Berkeley National Laboratory recently. It is a useful tool to perform micromachining, surface modification, and ion doping etc. The principle of the imprinter is to directly transfer the pattern from the mask to the substrate. It is capable to produce multiple shaped ion beams simultaneously. Therefore it is much more efficient to do micromachining for large volume production than conversional focused ion beam system. Different shaped masks and diverse ion species have been tested both on conductors and insulators. Furthermore, the ion beam imprinter can transfer patterns not only onto a planar target but also onto non-planar surfaces, for example the outer and inner surfaces of cylinders. The imprinting technique can also be applied in three-dimensional micromachining, for example using cylindrical masks to fabricate the medical stents.
DIRECT MEASUREMENT OF ION-INFLUENCED SURFACE DIFFUSION

The influences of low-energy ion bombardment on surface diffusion have been quantified directly for the first time. Bombardment of germanium diffusing on silicon by noble gas ions between 15 and 65thinspthinspeV affects the diffusional activation energy and preexponential factor in a strongly temperature-dependent way. Curiously, above about 850thinsp{degree}C the ion-influenced diffusivity actually falls below the thermal value. The results have significant implications for thin film growth by ion-assisted deposition processes. {copyright} {ital 1999} {ital The American Physical Society}
Internal Labor Markets, Firm-Specific Human Capital, and Heterogeneity Antecedents of Employee Idiosyncratic Deal Requests

A field study of 615 managers in 11 Korean manufacturing firms extends theory regarding labor contracting to the study of idiosyncratic deals i-deals. Despite i-deals' potential to benefit both employees and employers, economic theory asserts that employers attempt to reduce individual contracting by use of internal labor markets ILMs. This study identifies limits to that assertion by identifying conditions under which i-deals are sought, despite employee participation in ILMs. Furthermore, we develop and test theory reconciling the roles of ILMs and firm-specific human capital in employee requests for i-deals. Employee reports of ILM practices are negatively related to i-deal requests, whereas firm-specific human capital is positively related to these requests. In addition, we find an interaction between the two such that the suppressive effects of ILM reports on i-deal requests hold largely for workers with low firm-specific human capital. Individuals with high firm-specific human capital tend to seek i-deals despite reported ILM practices. I-deal requests also increase with group-level heterogeneity in firm-specific human capital. In all, our findings suggest that ILMs function as economic theory asserts for workers with limited firm-specific human capital, but they are less able to reduce i-deal requests among workers with higher firm-specific human capital.
Endovascular and Open Surgical Treatment of Brachiocephalic Arteries

Thesearteriesarealsoknownas thebrachiocephalic arteries. Atherosclerosis is the most common cause of occlusive disease of the brachiocephalic arteries, followed by Takayasu arteritis and radiation-induced arteritis. Occlusive diseases outnumber aneurysmal lesions by 10-1. It is generally agreed that all symptomatic lesions should be treated. Some suggest that suitable surgical candidates should undergo revascularization of the brachiocephalic arteries if stenosis is >75%, even if they are asymptomatic. However, there is consensus that an asymptomatic stenosis of >75% in the subclavian artery proximal to an internal mammary artery bypass to a coronary artery should be treated.
A method for increasing the electron density of tobacco mosaic virus in ultrathin tissue sections.

Abstract The electron-scattering capacity of tobacco mosaic virus (TMV) was enhanced by staining intact ultrathin sections of purified virus embedded in methacrylate and intracellular virus inclusion bodies in infected leaf mesophyll cells of tomato ( Lycopersicon esculentum Mill. var. Improved Pearson) with phosphotungstic acid (PTA). Individual particles resembling TMV rods, observed within intact sections of cells stained with PTA, could, in the absence of staining, be resolved only upon removal of the embedding polymer. A staining mechanism involving adsorption of tungsten ions on the surface of virus exposed during sectioning is discussed.
On zero-degree stochastic geometric programs

The Mellin transform is used to encode randomness in the constraint and objective function coefficients using the substituted dual function. This enables one to obtain statistical moments and the probability distribution of the optimal objective valueZ*. Advantage is taken of the form of the dual function and the limiting property of the lognormal distribution to prove that the probability distribution ofZ* approximates the lognormal distribution, independent of the distribution of the parameters. This is of importance because those probability distributions are seldom known; even if they are, a derivation of the distribution ofZ* is apt to be elusive. Further, the larger the number of stochastic parameters in the geometric program, the more closely, in general, does the distribution ofZ* approximate the lognormal distribution. Illustrative examples are provided.
Laser Machining of Structural Alumina: Influence of Moving Laser Beam on the Evolution of Surface Topography

Laser machining technique has emerged as an innovative tool to effectively machine the structural ceramics, which previously was nearly impossible using various conventional machining techniques. However, obtaining a desired surface finish via laser machining is still a critical issue. As many physical phenomena act simultaneously during laser machining, it is very difficult to understand their influence in real time and predict the surface topography. To address this issue, a multiphysics-based finite-element modeling approach was implemented to understand the influence of moving laser beam (with lateral overlap) on the generation of corresponding surface topography/profile/roughness during laser machining of structural alumina. A computation model that coupled heat transfer and computational fluid dynamics was designed to understand the combined influence of Marangoni convection, recoil pressure, cooling rates, and surface tension on the evolving surface topography during laser machining of structural alumina under various machining conditions. Both computational and experimental results evidently showed the systematic increase in surface roughness parameters with the increase in lateral overlap (0, 17, 33, 50, 67, and 83%). The results of the computational model are also validated by experimental observations with reasonably close agreement (±3.5%).
Developmental increase of aspartoacylase in oligodendrocytes parallels CNS myelination

Canavan disease, an autosomal-recessive neurogenetic disorder, is caused by mutations in aspartoacylase, an enzyme that deacetylates N-acetylaspartate to generate free acetate in the brain. Earlier studies have shown that aspartoacylase is primarily restricted to myelin synthesizing cells (oligodendroglia) in the CNS. These findings have led us to investigate the developmental expression of aspartoacylase gene in the rat brain in an attempt to shed more light on the role of this enzyme in myelination. In situ hybridization using a 35S riboprobe based on murine aspartoacylase cDNA was used in this study. The probe hybridized mostly to the white matter tracts with different densities depending on the age of the animal and region of the brain examined. Little or no hybridization signals were detected in the 1-day-old rats, whereas the signal was clearly detectable in most of the white matter regions of the CNS in the 11-day-old rats. The signal density markedly increased at postnatal day 17, the peak of myelination. Thereafter, the hybridization signals decreased somewhat but still could be observed in the adult animals. Thus, the developmental expression pattern of aspartoacylase gene in the postnatal brain closely parallels myelination in the CNS. In the CNS, the hybridization signal of ASPA appeared to be restricted primarily to oligodendrocytes, the primary myelin synthesizing cell type in the CNS. However, the signal was not detectable in rat sciatic nerve (Schwann cells) of the peripheral nervous system. These findings indicate that the role of N-acetylaspartate in myelin synthesis is restricted to the CNS. Furthermore, they provide additional support for the acetate deficiency hypothesis of Canavan disease and also make a stronger case for acetate supplementation as an immediate and inexpensive therapy for Canavan disease.
Determination of crystal growth kinetics from desupersaturation measurements

Abstract The growth kinetics of oxalic acid dihydrate have been determined in a multiparticle suspension by measuring (a) the solution concentration during growth and (b) the final crystal size distribution. The method of calculation involves the use of the number mean size together with the second and third moments of the product size distribution. It is necessary to assume that the number of crystals remains constant and that crystal growth rate is independent of size.
Aspirin—A national survey IV: In Vitro dissolution of aspirin formulations

The results of a national survey of the in vitro dissolution rates of aspirin tablets are presented. Dissolution profiles by both the proposed USP XX basket method and a paddle method are compared. The methods were used to analyze 59 tablet formulations representing 38 manufacturers. Each tablet was subjected to the dissolution procedure in 500 ml of pH 4.5 buffer solution, and an aliquot was sampled automatically and analyzed by an automated system. In 30 min, 22% of the samples tested using the basket method failed the proposed USP XX dissolution requirement. Seventy-five percent of the samples tested by the paddle method also failed the proposed dissolution requirement.
4-Methyl-1,2,3-triazine†

[77202-08-5] C4H5N3 (MW 95.12) InChI = 1S/C4H5N3/c1-4-2-3-5-7-6-4/h2-3H,1H3 InChIKey = FXKQPQOOZSXQAG-UHFFFAOYSA-N (an electron-deficient heteroaromatic azadiene capable of participation in inverse electron demand Diels–Alder reactions with electron-rich dienophiles employed for preparation of substituted pyridines1) Physical Data: mp 31 °C. Solubility: sol CHCl3, CH2Cl2, EtOH. Form Supplied in: plates (i-Pr2O). Preparative Method: an ice-cold solution of 0.01 mol of N-amino-5-methylpyrazole in 30 mL of CH2Cl2 and 10 mL of H2O is treated with 0.02 mol of solid Sodium Periodate or potassium periodate with stirring. The resulting mixture is allowed to stir at 0–5 °C overnight and then extracted repeatedly with CHCl3. The CHCl3 phase is dried over Na2SO4, concentrated, and purified by recrystallization or column chromatography on silica gel.2 Handling, Storage, and Precautions: stable at room temperature and is probably hygroscopic.
Afghan Refugee Health: Some Findings and Suggestions

Health problems are often associated with migration, particularly for refugees from such war-torn countries as Afghanistan. This article reports findings of an ethnographic study of Afghan refugees in Northern California. Participant observation and various informal and semistructured interviews of 29 refugees revealed difficulties in social support, cultural conflict, language, economics, and family adjustment. These difficulties, added to traumatic refugee flight sequelae, were expressed in psychosomatic symptoms and high stress scores as indicated by the Health Opinion Survey, which elicits psychosomatic indications of stress. These themes suggest needs for culturally appropriate health and social services.
Simultaneous reduction of a complex skew matrix and a Hermitian matrix

Abstract A canonical form and a complete set of invariants are obtained for the simultaneous reduction of two complex matrices, one of which is skew symmetric and the other Hermitian.