cssi/SciSciGPT-SciSciNet huggingface dataset:
EXPERIMENTAL STUDIES OF DIFFUSION ON FRACTAL SURFACES

Composites are formed by sorption of Nafion, an ion exchange polymer, onto inert substrates of two different microstructures: microcylinders (neutron track etched membranes) and microspheres. Flux of a neutral redox probe (hydroquinone) through the composites is measured voltammetrically. Data for the microsphere composites are presented for variation in volume fraction and bead radii. Flux is shown to increase as the ratio of surface area of the substrate to volume of Nafion increases. The enhancement is ascribed to a facile surface diffusion domain at the interface between the Nafion and the inert substrates. Enhancements are larger in the microcylinder composites. Images of the microsphere composites appear fractal. For the microsphere composites, the power law relating flux to a characteristic dimension (microsphere radius) has an exponent of 0.78. A similar analysis for the cylinders has an exponent of 1. The analysis also shows that the fundamental transport rates of surface and bulk diffusion are ...
DETECTING NEW AND EMERGING EVENTS IN STREAMING NEWS DOCUMENTS

Recognizing new and emerging events in a stream of news documents requires understanding the semantic structure of news reported in natural language. New event detection (NED) is the task of recognizing when a news document discusses a completely novel event. To be successful at this task, we believe a NED method must extract and represent four principal components of an event: its type, participants, temporal, and spatial properties. These components must then be compared in a semantically robust manner to detect novelty. We further propose event centrality, a method for determining the most important participants in an event. Our NED methods produce a 29% cost reduction over a bag-of-words baseline and a 17% cost reduction over an existing state-of-the-art approach. Additionally, we discuss our method for recognizing emerging events: the tracking and categorization of unexpected or novel events.
Breath-hold MR cine angiography of coronary arteries in healthy volunteers: value of multiangle oblique imaging planes.

Breath-hold MR cine angiography was used to depict the coronary arteries in healthy volunteers. Multiangle oblique imaging planes were evaluated for feasibility in showing continuous segments of the proximal and middle portions of the left anterior descending and right coronary arteries.Eighteen healthy subjects were examined with a 1.5-T MR imager. Fat-suppressed fast gradient-echo images (TR = 9.8 msec, TE = 3.5 msec) were acquired with a 13-cm receive surface coil. A segmented k-space data acquisition was used to obtain images of the coronary arteries at several phases of the cardiac cycle within a single breath-hold. Multiangle double oblique images that were tangential and sequential to the epicardial surface of the left ventricle were used to show the left anterior descending artery, and oblique coronal images were used to show the right coronary artery. Images of consecutive slice locations were shown in a cine format, and the length of each major coronary artery that was continuously visualized wa...
Genetic and environmental control of potato glycoalkaloids

Genetic and environmental factors that can cause potato tubers and processed products to have excessive glycoalkaloid levels (> 20 mg/100 g fresh wt) are reviewed and discussed. Measures that breeders, growers, processors, and distributors might take to maintain glycoalkaloid levels at their present low levels are suggested.
Algorithm for efficient elastic transport calculations for arbitrary device geometries

With the growth in interest in graphene, controlled nanoscale device geometries with complex form factors are now being studied and characterized. There is a growing need to understand new techniques to handle efficient electronic transport calculations for these systems. We present an algorithm that dramatically reduces the computational time required to find the local density of states and transmission matrix for open systems regardless of their topology or boundary conditions. We argue that the algorithm, which generalizes the recursive Green's function method by incorporating the reverse Cuthill-McKee algorithm for connected graphs, is ideal for calculating transmission through devices with multiple leads of unknown orientation and becomes a computational necessity when the input and output leads overlap in real space. This last scenario takes the Landauer-Buttiker formalism to general scattering theory in a computational framework that makes it tractable to perform full-spectrum calculations of the quantum scattering matrix in mesoscopic systems. We demonstrate the efficacy of these approaches on graphene stadiums, a system of recent scientific interest, and contribute to a physical understanding of Fano resonances which appear in these systems.
Prolactin and Tadpole Growth.

SummaryMammalian prolactin inhibits thyroxin-induced resorption of the tail in Rana catesbeiana tadpoles. Mammalian growth hormone does not show this effect. The possible importance of prolactin as a larval growth hormone in amphibians is emphasized.
Electrokinetics at liquid/liquid interfaces

Electrokinetic effects at liquid/liquid interfaces have received considerably less attention than at solid/liquid interfaces. Because liquid/liquid interfaces are generally mobile, one might expect electrokinetic effects over a liquid/liquid interface to be faster than over an equivalent solid surface. The earliest predictions for the electrophoretic mobility of charged mercury drops – distinct approaches by Frumkin, along with Levich, and Booth – differed by , where is the radius of the drop and is the Debye length. Seeking to reconcile this rather striking discrepancy, Levine & O’Brien showed double-layer polarization to be the key ingredient. Without a physical mechanism by which electrokinetic effects are enhanced, however, it is difficult to know how general the enhancement is – whether it holds only for liquid metal surfaces, or more generally, for all liquid/liquid surfaces. By considering a series of systems in which a planar metal strip is coated with either a liquid metal or liquid dielectric, we show that the central physical mechanism behind the enhancement predicted by Frumkin is the presence of an unmatched electrical stress upon the electrolyte/liquid interface, which establishes a Marangoni stress on the droplet surface and drives it into motion. The source of the unbalanced electrokinetic stress on a liquid metal surface is clear – metals represent equipotential surfaces, so no field exists to drive an equal and opposite force on the surface charge. This might suggest that liquid metals represent a unique system, since dielectric liquids can support finite electric fields, which might be expected to exert an electrical stress on the surface charge that balances the electric stress. We demonstrate, however, that electrical and osmotic stresses on relaxed double layers internal to dielectric liquids precisely cancel, so that internal electrokinetic stresses generally vanish in closed, ideally polarizable liquids. The enhancement predicted by Frumkin for liquid mercury drops can thus be expected quite generally over ideally polarizable liquid drops. We then reconsider the electrophoretic mobility of spherical drops, and reconcile the approaches of Frumkin and Booth: Booth’s neglect of double-layer polarization leads to a standard electro-osmotic flow, without the enhancement, and Frumkin’s neglect of the detailed double-layer dynamics leads to the enhanced electrocapillary motion, but does not capture the (sub-dominant) electrophoretic motion. Finally, we show that, while the electrokinetic flow over electrodes coated with thin liquid films is faster than over solid/liquid interfaces, the Dukhin number, , which reflects the importance of surface conduction to bulk conduction, generally increases by a smaller amount [ ], where is the thickness of film and is the length of the electrode. This suggests that liquid/liquid interfaces may be utilized to enhance electrokinetic velocities in microfluidic devices, while delaying the onset of high- electrokinetic suppression.
Public Goods and Optimal Income Taxation

Previous optimal income tax studies have generally ignored government expenditures as a policy tool for affecting distribution. Using simulations, this article analyzes the properties of the optimal linear income tax where both public and private consumption enter individuals' utility functions.
A comparison of stapedial reflex fatigue with repetitive stimulation and single‐fiber emg in myasthenia gravis

The pattern of stapedial reflex fatigue in response to pulsed acoustic stimulation was measured and compared to results of repetitive nerve stimulation and single-fiber electromyography (EMG) in 89 patients with myasthenia gravis. Studies were also made on 22 patients with other neuromuscular disorders and 40 control subjects with no evidence of neuromuscular impairment. Stapedial reflex fatigue exceeded normal control values in 84% of the patients with myasthenia gravis. Repetitive stimulation and single-fiber EMG measurements were abnormal in 56% and 91% of this same population, respectively. Stapedial reflex abnormalities were most prevalent in patients with mild forms of myasthenia (predominantly ocular or oropharyngeal weakness). Of 22 nonmyasthenic patients with neuromuscular disease tested, 6 had abnormal stapedial reflex fatigue according to our normal values, indicating that this form of testing also detects other diseases of the motor unit. The measurement of stapedial reflex fatigue is painless, is easy to perform, and requires minimal patient cooperation. Due to the relatively high occurrence of abnormal stapedial reflex fatigue in patients with myasthenia gravis, this procedure appears to have considerable potential value in screening and monitoring patients for the presence of defects in neuromuscular transmission.
Cognitive-behavioral treatment for depressed adolescents*

The purpose of this study was to test the efficacy of two versions of a cognitive-behavioral intervention for depressed adolescents. Fifty-nine high school students, aged 14–18, meeting DSM-III and RDC criteria for a diagnosis of depression were randomly assigned to one of three conditions: Adolescent-and-Parent, Adolescent-Only, and Wait-List. The treatments were: a) an adaptation of the Coping with Depression Course (CWD), a cognitive-behavioral group intervention teaching skills for increasing pleasant activities, relaxation, controlling depressive thoughts, improving social interaction, and communication, negotation and conflict resolution skills; and b) an intervention for the parents. The results showed that, compared to the wait-list subjects, treated subjects improved significantly on the depression measures. These gains were maintained at two years posttreatment. There was a strong trend for the results to favor the Adolescent-and-Parent condition over the Adolescent-Only condition, but only one of numerous comparisons attained statistical significance.
Absorption enhancement in thin-film organic photovoltaics with double plasmonic structures

Broadband light absorption enhancement is numerically investigated for double plasmonic structures in thin-film organic photovoltaics. Due to the combined excitation of different Surface Plasmon modes, the absorption enhancement of about 67% is obtained.
Mechanisms of the in vitro antimutagenic action of chlorophyllin against benzo[a]pyrene: Studies of enzyme inhibition, molecular complex formation and degradation of the ultimate carcinogen

Abstract Mechanisms of the antimutagenic action of chlorophyllin (CHL) towards benzo[a]pyrene (BP) were studied in vitro. In the Salmonella assay, CHL inhibited the mutagenic activity of BP in the presence of an S9 activation system and was particularly effective against the direct-acting ultimate carcinogen, benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE). Spectral studies indicated that the time-dependent hydrolysis of BPDE to tetrols was augmented in the presence of CHL concentrations on the order of 5 μM. Dose-related inhibition of several cytochrome P450-dependent enzyme activities was observed upon addition of CHL to in vitro incubations. Spectral changes for the interaction between CHL and cytochrome P450 indicated that CHL does not bind to the active site of the enzyme, but exerts its inhibitory effect indirectly. This was achieved by inhibiting NADPH-cytochrome P450 reductase (Ki ∼ 120 μM with cytochrome c as substrate), and did not involve lowering of the effective substrate concentration by complex formation with the procarcinogen. It is concluded that the in vitro antimutagenic activity of CHL towards BP involves accelerated degradation of the ultimate carcinogen, with inhibition of carcinogen activation occurring only at high CHL concentrations. The latter mechanism is unlikely to occur in vivo following p.o. administration due to the limited uptake of CHL from the gut, but tissue concentrations may be sufficiently high to cause degradation of BPDE.
Actions speak louder than words: An institutional perspective on the Securities and Exchange Commission

Abstract This paper employs an institutional perspective and quantitative methods to examine Securities and Exchange Commission (SEC) funding patterns. It is hypothesized that the institutional perspective will provide insights into the funding process not provided by more traditional modes of thought. The results suggest that SEC funding and enforcement actions are related. They also suggest that the economic health of the nation influences the amount of resources received by the SEC. Finally, there appears to be a link between political party affiliation and the predisposition to allocate funds to the SEC. The study suggests that SEC enforcement activities may not be totally random.
Regioselective synthesis of multifunctional hybrid polysiloxanes achieved by Pt-nanocluster catalysis.

The first example of “Pt”−nanocluster-catalyzed regioselective generation of hybrid polymers via attachment of organic functionalities to evenly distributed Si−H bonds of poly(methylhydro)siloxane is described. In addition, participation of Pt−nanoclusters as an active catalyst was evidenced by various spectroscopic techniques during the catalytic transformations.
Management of Pediatric Obesity: A Lifestyle Modification Approach

Over the last decades, pediatric obesity has become a global epidemic with worldwide estimates as high as 43 million children and adolescents affected, and this number is rising at an exponential rate. With pediatric obesity comes a host of co-morbidities including impaired glucose tolerance, dyslipidemia, hypertension, and impaired liver function. Treatment of this population has proven to be challenging for many reasons. For patients, a new baseline exists consisting of an increasingly sedentary lifestyle as well as a lack of availability of affordable healthy alternatives. In addition, there is an overwhelming presence of energy-dense foods. For physicians, there are many issues including lack of time, training, and reimbursement. The most efficacious and reliable way to treat this population and its co-morbidities is with a healthy, balanced lifestyle consisting of a realistic diet plan and exercise regimen. The is the cornerstone of therapy in the Center for Obesity And its Complications in Health (COACH) clinic which is Children’s Medical Center’s (Dallas, TX) strategy to combat and treat pediatric overweight and obesity. Lifestyle changes of diet and exercise plans are tailored to each individual’s interests and metabolic needs in COACH which is a multi-disciplinary clinic. Additionally, co-morbidities are screened for and treated aggressively to help prevent long-term complications of overweight and obesity. If others do similar interventions in their communities, this global epidemic has the possibility of more positive outcomes than those currently projected.
Morphometric analysis of muscle cell changes in the short‐term partially obstructed rabbit detrusor

It has been shown previously that both degenerative and regenerative muscle cell changes occur in the partially obstructed rabbit detrusor and are largely reversed after relief of the obstruction [Elbadawi et al., 1989]. In the present study, we quantitated these changes in the same animal model to define their chronologic evolution. Specimens for electron microscopic study were obtained from the bladder body detrusor in three normal rabbits, fifteen rabbits with 1–14 days of partial bladder outlet obstruction, and seven rabbits relieved of a 7-day obstruction for 14 or 28 days. Sections from each specimen were analyzed quantitatively for the prevalence of normal, degenerative, and regenerative muscle cell profiles by determining the percentage of photographic prints showing only normal muscle cells and those depicting muscle cell change. Prints of 684 semirandom and 95 truly random photographs were so analyzed. Absolute counts of the various types of muscle cell profiles were also made in the former group of prints for comparison. In addition, 174 prints were analyzed for the presence of hypertrophic cell profiles. All data were analyzed statistically by the appropriate methods. Our observations led to classification of the material studied into three categories: (a) control, which includes both the normal and 1-day obstructed groups; (b) obstructed, including the 3–7 day obstructed groups in which both degenerative and regenerative changes were maximal; and (c) recovered, including the 14-day obstructed and both 14- and 28-day deobstructed groups in which muscle cell changes were markedly—though incompletely—reversed. Our findings form a structural basis for the changes in contractility and biochemical profile of the partially obstructed detrusor that have been described previously in the same model [Malkowicz et al., 1986].
A stochastic algorithm for optimization problems with continua of inequalities

Optimization algorithms for solving mathematical programming problems involving continua of inequalities are presented. The algorithms use an outer-approximation method, by which they attempt to approximate, at each point, the maxima of sets of inequality constraints. They do so by performing random experiments, resulting in a finite number of points, over which the maximum is taken. They use constraint-dropping schemes, by which they eliminate points from the constraint set at hand, which are felt to be irrelevant. At each point that the algorithms construct, they evaluate a measure of optimality, which indicates the distance of the point from the set of solutions of the optimization problem. They use this measure to determine the number of random experiments performed. Thus, the number of such experiments tends to be small initially, when the points at hand are far from optimal, and they tend to increase when an optimal point is approached.
Adaptive control of propellant slosh for a launch vehicle with multiple tanks

This paper discusses the use of an adaptive system to stabilize a multi-tank launch vehicle with sloshable fuel. The adaptive system utilizes a sensor to measure the fluid slosh angle, a recursive-least-squares estimator to estimate the natural frequency of the sloshing fuel, and a linear filter which stabilizes the unstable fuel slosh using the frequency estimate. Single-input and multiinput estimators were investigated. The time-varying complexity of the slosh control loop keeps the system persistently excited through flight, even though the attitude is controlled by a conventional PID controller. For the first portion of flight, the adaptive system maintains stability. A modification is proposed for latter portions of flight. The approach requires no tank baffles or partitions.
Gas curtain for mitigating hydrocarbon contamination of EUV lithographic optical components

ABSTRACT Calculations were carried out to study the effectiveness of a gas curtain for mitigating contamination from hydrocarbon gasesin extreme ultraviolet (EUV) lithography tools. The momentum, energy and mass transport in the curtain and surroundingregions were calculated using a two dimensional finite volume model of a lithography tool. Argon was used for the gascurtain. The results from the calculations quantify the relationship between the argon flow rate and the hydrocarbon partialpressure in the region of the optical elements. In general, the hydrocarbon partial pressure decreases as the mass transfer Peclet number, Pe VhJD, increases, where V is the velocity of the argon, h is the thickness of the gas curtain and D is themass diffusivity. An argon flow rate of 12.2 torrl/s is required to reduce the hydrocarbon partial pressure from iO to l0b0ton in the specific lithography tool considered here. The EUV transmission in the tool with the gas curtain is 0.93. This is alarge improvement over the 0.5
More than fair: Outcome dependence, system justification, and the perceived legitimacy of authority figures

Legitimacy is a source of power for authorities because it promotes voluntary deference on the part of followers. From a system justification perspective, there is also reason to believe that power is a source of perceived legitimacy. We report five studies demonstrating that in addition to procedural fairness and outcome favorability, outcome dependence is an independent contributor to perceived legitimacy. In two cross-sectional field studies and one panel study, we hypothesized and found that dependence on an authority figure is positively associated with appraisals of legitimacy, measured in terms of trust and confidence in, empowerment of, and deference to authority. These effects were demonstrated in educational, political, and legal settings. Two additional experiments provided direct causal evidence for the hypothesized effect on both perceived legitimacy and voluntary deference (i.e., acquiescence to additional requests). We also found that participants assigned to a high (vs. low) dependence condition judged their outcomes to be more favorable, despite the fact that the outcomes were identical in the two conditions; this effect was mediated by perceived legitimacy. Taken as a whole, these findings suggest that perceived legitimacy is enhanced not only when authorities exercise fair procedures and deliver favorable outcomes, but also when subordinates are dependent on them. Implications for society and the study of legitimacy and social power are discussed.
Effects of ethanol and acetaldehyde on iron-sulfur centers in the mitochondrial respiratory chain

Abstract Incubation of submitochondrial particles with relatively low concentrations of ethanol (20–100 m m ) or acetaldehyde (1–10 m m ) produces alterations in the electron paramagnetic resonance spectra of the iron-sulfur centers in the NADH dehydrogenase segments of the respiratory chain. The iron-sulfur centers in the NADH dehydrogenase region are most sensitive to both ethanol and acetaldehyde, in comparison to the iron-sulfur centers in succinate dehydrogenase and the cytochrome b - c region. Centers N-3, 4, N-5, 6 and N-1b are affected after relatively short incubation periods (3–30 min) while center N-2 shows considerable sensitivity over somewhat longer incubations (20–90 min). The most ethanol-sensitive center in the succinate dehydrogenase region of the respiratory chain is high potential iron-sulfur protein-type center S-3. Potentiometric analysis shows that these alterations are not due to simple changes in the redox state caused by addition of dissolved oxygen. Changes in the electron paramagnetic resonance spectra can be correlated with decreased rates of oxidation of NADH and, to a lesser extent, succinate in both ethanol- and acetaldehyde-treated submitochondrial particles.
Colectomy without mechanical bowel preparation in the private practice setting

Background Despite randomized trials and meta-analyses demonstrating the safety of omitting mechanical bowel preparation (MBP) before colorectal surgery, private practice surgeons may hesitate to eliminate MBP for fear of being outside community standards. This study evaluated the safety of eliminating MBP before colectomy in a private practice setting.
Sequential migration theory and evidence from Peru.

Abstract The standard human capital model of labor migration has been successful in explaining several empirical regularities of the migration process. However, there are a number of empirical facts that have not yet been explained or empirically tested; among them, that migrants usually perform more than one move in their lifetime; return migration accounts for a very important share of total migration rates; and there is a high positive correlation between in- and out-migration rates in the more advantageous regions. This paper presents both a simple model explaining these facts and an empirical analysis using data from Peru.
Multiple-Scattering Model for Light Transmission through Optically Thick Clouds*†

A linear-system model has been developed to predict irradiance distributions of visible light below an idealized optically thick atmospheric cloud, which is illuminated from above in an arbitrary manner. The model offers elegant mathematical simplicity at the expense of some precision. As such, it is applicable to a broad class of problems in which correct functional forms are required, but levels of accuracy better than a factor of 2 are not necessary. Optical thicknesses can range from about 5 to 32. One example of a problem in this class, the design of a laser communication system to operate through clouds, provided the original motivation for development of the light-transmission model. The optical effects of the cloud are calculated by means of a four-dimensional linear superposition integral, which takes account of multiple scattering. Two illustrations of the method are given in detail, with incident illumination represented by a tightly collimated beam and by a sum of infinite plane waves, respectively.
FutureGen 2.0 Monitoring Program: An Overview of the Monitoring Approach and Technologies Selected for Implementation

Abstract The FutureGen 2.0 Project will design and build a first-of-its-kind, near-zero emissions coal-fueled power plant with carbon capture and storage (CCS). To assess storage site performance and meet the regulatory requirements of the Class VI Underground Injection Control (UIC) Program for CO 2 Geologic Sequestration, the FutureGen 2.0 project will implement a suite of monitoring technologies designed to 1) evaluate CO 2 mass balance and 2) detect any unforeseen loss in CO 2 containment. The monitoring program will include direct monitoring of the injection stream and reservoir, and early-leak-detection monitoring directly above the primary confining zone. It will also implement an adaptive monitoring strategy whereby monitoring results are continually evaluated and the monitoring network is modified as required, including the option to drill additional wells in out-years. Wells will be monitored for changes in CO 2 concentration and formation pressure, and other geochemical/isotopic signatures that provide indication of CO 2 or brine leakage. Indirect geophysical monitoring technologies that were selected for implementation include passive seismic, integrated surface deformation, time-lapse gravity, and pulsed neutron capture logging. Near-surface monitoring approaches that have been initiated include surficial aquifer and surface- water monitoring, soil-gas monitoring, atmospheric monitoring, and hyperspectral data acquisition for assessment of vegetation conditions. Initially, only the collection of baseline data sets is planned; the need for additional near- surface monitoring will be continually evaluated throughout the design and operational phases of the project, and selected approaches may be reinstituted if conditions warrant. Given the current conceptual understanding of the subsurface environment, early and appreciable impacts to near-surface environments are not expected.
3-D Monte Carlo and discrete ordinates void coefficient analysis for the los alamos national laboratory omega west reactor using MCNP and threedant

Three-dimensional Monte Carlo and discrete ordinates computational modeling techniques have been used to characterize void coefficient behavior for three experimental channels and several fuel assemblies in the Los Alamos Omega West nuclear reactor using MCNP and THREEDANT. Good agreement is observed in void coefficient behavior predicted by MCNP and THREEDANT. The experimental-channel gross-voiding calculations predict the existence of positive void coefficients due to overmoderation conditions. The fuel assemblies exhibit, for the most part, negative void coefficients, although the possibility of localized small positive void coefficients for one of the five assemblies analyzed is indicated.
Rabbi and Magister : Overlapping intellectual models of the twelfth-century renaissance

Elka Klein’s writings have illuminated reciprocal and distinctive characteristics of the social and intellectual lives of Jewry in Iberia and by comparison Northern Europe during the High Middle Ages. This article honors her insights, by comparing the development of biblical hermeneutics at the Abbey of St. Victor in Paris and in the writings of Abraham ibn Ezra. Hugh of St. Victor’s introduction to the study of Scripture, Didascalicon, provides a program for the individual student to integrate all branches of human knowledge into the search for Divine Wisdom that may be found only in Scripture. The innovation in Hugh’s program is the emphasis on the “literal” or “historical” sense of Scripture as the solid basis for the development of theological study. Grammar and rhetoric were stepping stones that led the young theologians to higher levels of Divine Wisdom. The introduction to Abraham ibn Ezra’s commentary on the Pentateuch constitutes a parallel point of orientation for twelfth-century Jewish readers. A close reading of ibn Ezra’s prologue maps the hermeneutical approaches that different communities – Christian, rabbinic Jewish, and Karaite – utilized in their expositions of the Pentateuch. After critiquing each community, ibn Ezra offers his own approach that builds an overall framework for correct interpretation on the foundation of grammar and the rabbinic oral tradition. From this perspective, the article demonstrates that during this period Jews and Christians, both in Iberia and Northern Europe, focused on harmonizing reason and revelation. Both communities used grammar as the primary criterion for evaluating the accumulation of traditional sources. Both approaches intended to develop students, who were capable of understanding that “reason is the angel that mediates between God and humanity.”
Errorless Discrimination Learning in the Pigeon: Effects of Chlorpromazine and Imipramine

Chlorpromazine or imipramine disrupts a pigeon's performance on a discrimination between a vertical and horizontal line only if the discrimination was learned with errors. Errorless learning is obtained if training starts with an easy-to-learn discrimination of color and shifts progressively to the more difficult horizontal-vertical discrimination.
Identification of point defects responsible for laser-induced ultraviolet absorption in LiB 3 O 5 (LBO) Crystals

Electron paramagnetic resonance (EPR) has been used to identify and characterize point defects in lithium triborate (LiB3O5) crystals grown for nonlinear optical applications. As-grown crystals contain oxygen vacancies and lithium vacancies (as well as trace amounts of transition-metal ions in a few samples). Exposing a crystal to ionizing radiation at 77 K produces “free” electrons and holes. These electrons are trapped at the pre-existing oxygen vacancies and give rise to an EPR signal with a large hyperfine from one 11B nucleus. The corresponding holes become self-trapped on oxygen ions as a result of the significant lattice relaxation of a nearest-neighbor fourfold-bonded boron ion. This gives rise to an EPR signal with a smaller 11B hyperfine pattern due to the oxygen’s threefold bonded boron neighbor. Warming the crystal to approximately 130 K destroys the self-trapped hole centers that were initially formed, and allows a second holelike signal to be observed (which in turn decays between 150 and 200 K). The structure of the second hole center is very similar to the self-trapped hole center and a neighboring lithium vacancy makes this latter center more thermally stable. The EPR spectra from Ni+ and Cu2+ ions are also reported.
The Nonactive Site Cysteine Residues of Yeast Protein Disulfide Isomerase Are Not Required for Cell Viability

Protein disulfide isomerase (PDI), the product of the essential PDI1 gene of Saccharomyces cerevisiae catalyzes oxidization of thiols, reduction of disulfide bonds, and isomerization of disulfides. It can also act as a chaperone to facilitate folding of denatured proteins. The protein has 6 cysteine (Cys) residues. Four of these Cys are part of the 2 thioredoxin-like catalytic sites (-CGHC-), one of which is located near the N- and the other near the C-terminus. In addition, it has 2 non-active site Cys near the N-terminus. The function of these non-active site Cys of yeast PDI is poorly understood. Whereas in yeast PDI, these Cys residues are in the vicinity of the N-terminal-most active site, in mammalian PDI their position is closer to the C-terminal-most active site. We have examined their role and that of the active site cysteines by constructing an extensive set of mutants in which the Cys were systematically replaced by Ser. As reported earlier, the N-terminal Cys of the two active sites sequences of yeast PDI were found to be required for cell viability, but mutation of the C-terminal Cys to Ser in the two active sites was not lethal. We found that replacement of the two non-active site Cys with Ser did not affect cell viability, but in the case of the double mutant in which both Cys were replaced by Ser the processing and secretion of CPY was impaired.
Recollections of parent characteristics and attachment patterns for college women of intact vs. non-intact families.

Abstract This study contrasted offsprings’ attachment patterns and recollections of parent characteristics in two college samples: 147 females from intact biological parents and 157 females of parental divorce. Secure females from intact or non-intact families rated parents positively, while insecure females rated parents as absent, distant, and demanding. In contrast to females from intact families, females of parental divorce reported a less secure attachment, lower self-esteem, a greater fearful avoidance pattern, and rated their biological fathers and mothers more negatively.
Evolution of microstructure and mechanical properties of in situ consolidated bulk ultra-fine-grained and nanocrystalline Zn prepared by ball milling

Abstract The evolution of the microstructure and mechanical properties of ultra-fine-grained and nanocrystalline Zn induced by ball milling at room temperature are studied systematically. The yield stresses measured from miniaturized disk bend tests and tensile tests are consistent with the microhardness results and generally increase with the decrease of average grain size. A dramatic decrease of hardness during milling from 1 to 3 h is a reflection of the increase of average grain size from 80 to 240 nm due to the initial unstable grain size and therefore, grain growth in this period. Young's modulus remains almost the same for samples milled for different times and is that for conventional grain size Zn. A transition from bending to membrane stretching is observed in the force–displacement curves for Zn ball milled for ≤18 h. The variation of transition strain with milling time could be related to the evolution of grain size distribution and therefore hardness during milling.
Photon migration in a model of the head measured using time- and frequency-domain techniques: potentials of spectroscopy and imaging

The use of time- and frequency-domain spectroscopy for the detection of brain oxygenation and the localization of tissue regions exhibiting brain-bleeding has been suggested recently by Chance and coworkers. In this study, we explore the effect of the skull (with minimal absorbance and greater scattering properties) upon measurements of photon migration within the underlying brain tissue (of comparatively greater absorbance and smaller scattering properties). Using the diffusion approximation to understand photon migration within the layered medium, we show that the effect of a transmitting layer can be significant, yet may considered negligible at significant source and detector separations in time- and frequency-domain measurements. Using Monte Carlo simulation of photons migrating within a model consisting of (i) a central core ((mu) sb equals 8 cm-1, (mu) ab equals 0) and (ii) an annulus ((mu) ss equals 24 cm-1, (mu) a equals 0), we demonstrate the contribution of an additional 'time-of-flight' to time-domain spectra (TDS) and an additional phase-shift to frequency-domain spectra (FDS) due to the presence of the highly scattering layer. Under conditions of changing absorbance ((mu) ab equals 0 - 0.075 cm-1) in the central core, our results show that the diffusion approximation also provides description of the changes seen in TDS and FDS derived from Monte Carlo simulation. Finally, upon mapping of volumes sampled by the migrating photons, we characterize the capacity for 'light-channelling' within the highly scattering layer as a function of source-detector separation and core absorbance.
Temporal variability in transit-based accessibility to supermarkets

Food desert studies attempt to identify geographic areas in which people lack access to sources of healthy food. While academic and policy research often defines access to food stores using simple Euclidean distance or road network metrics, dense urban areas with large public transit systems call for more sophisticated methods of determining access. It is particularly important to understand the level of access the transit-dependent population has to healthy food vendors, as their mobility is largely constrained by the routes and scheduling of their local public transportation system. In this study, we analyze public transit access to supermarkets in Cincinnati, Ohio. Using General Transit Feed Specification (GTFS) data from the Southwest Ohio Regional Transit Authority (SORTA) and the Transit Authority of Northern Kentucky (TANK) and custom ArcGIS tools, we calculate the time it takes to travel from each Cincinnati census block to its nearest supermarkets at different times of the day. This transit-travel-time matrix allows us to investigate food deserts that change shape based on the time of day considered and to calculate the temporal variability in block-level access. Also, by combining this time-dependent analysis with census data on race, income, and age, we search for disparities in average levels of accessibility. The results of this analysis identify the areas and subpopulations in Cincinnati with the greatest need for improved access to healthy food stores and will demonstrate how schedule-dependent transportation can be factored into measures of accessibility. Ultimately, this study paints a more complete and realistic picture of food deserts in Cincinnati and helps policy-makers better target interventions aimed at mitigating their effects.
Cognitive-behavior therapy for medically unexplained symptoms: A critical review of the treatment literature

Research has indicated that substantial numbers of physical or medical symptoms presented by patients remain unexplained medically. For example, studies have indicated that less than 25% of physical complaints presented to physicians have known or demonstrable organic or biological causes. Cognitive-behavior therapy (CBT) provides for a potentially effective means of impacting on this significant public health problem, both medically and psychologically. This paper reviews the extant literature regarding CBT for medically unexplained symptoms, as well as three related disorders—chronic fatigue syndrome, fibromyalgia, and noncardiac chest pain. Whereas this review provides support for the efficacy of CBT for such problems (e.g., effect sizes for CBT compared to control conditions centered around .40), it also identified a variety of methodological limitations regarding the studies themselves. Based on this analysis, recommendations for future research endeavors are provided and the implications of this area for prevention and treatment are offered.
A STUDY OF FATIGUE AND CREEP BEHAVIOUR OF FOUR HIGH TEMPERATURE SOLDERS

Creep and cyclic deformation behavior of two lead-free high temperature solder alloys, 95Sn-5Ag and 99Sn-1.0Cu, a high lead alloy 97.SPb-1.SAg-1.0Sn, and an Ag-modified eutectic alloy 62.SSn-36.1Pb-1.4Ag, were studied. Room temperature and high (100°C and 150°C) temperature fatigue tests (with cyclic strain amplitude up to 6.0%) for the four solders were conducted, with the fatigue lives ranging from a few cycles to more than 100,000 cycles. It is shown that among the alloys studied, 62.SSn-36.1Pb-1.4Ag (the modified Sn-Pb eutectic alloy) has the lowest fatigue resistance in term of low cycle fatigue life (strain controlled). The high lead alloy, 97.SPb-1.5Ag-1.0Sn, has the highest strain fatigue resistance in the large strain region (Δ > 2.0%). Temperature has a significant effect on alloys 95Sn-5Ag and 99Sn-1.0Cu, but has a negligible effect on the Ag modified Sn-Pb eutectic alloy 62.5Sn-36.1Pb-1.4Ag and 97.5Pb-1.5Ag-1.0Sn. Creep studies show that these alloys generally have a very significant primary creep regime (up to 20%); thus, any realistic constitutive relation has to take such a primary creep phase into consideration. Cyclic deformation of alloy 95Sn-SAg was simulated by using a constitutive relation built upon a 2-cell model, which covers both primary and secondary creep. This model provides a good estimate of the peak stresses (the minimum stress and the maximum stress in each cycle); it agrees with experimental results when the applied cyclic strain is small and/or the applied strain rate is very low.
Trade-offs in nonlinearly recorded matched filters

Here, we introduce a general nonlinearly-recorded matched filter that we term as the Fractional Power Filter (FPF). The Classical Matched Filter (CMF), the Phase-Only Filter (POF) and the Inverse Filter (IF) are special cases of the FPF. It is shown that by varying the degree of nonlinearity used in forming the FPFs, we can trade-off the noise tolerance of the filter against its correlation peak sharpness. It is also shown that the fractional power concept can be extended to distortion-invariant composite filters.
Further observations on the sonographic spectrum of gestational trophoblastic disease

Sonograms of 27 patients with gestational trophoblastic disease were evaluated and categorized according to newer concepts regarding the pathology and pathogenesis of this disorder. The patients were assigned to the following subgroups: (1) classical or complete mole; (2) partial or incomplete mole; (3) coexistent mole and fetus; (4) hydropic degeneration of the placenta; (5) locally invasive mole; and (6) metastatic trophoblastic disease, including choriocarcinoma. The utility of this categorization and of ultrasound in the diagnosis and subsequent management of these patients is presented.
The fundamentals of American security

0 ur best journals and worst statesmen sound the same theme. A new era has dawned, and the lessons of past decades, not to mention centuries, no longer pertain. America’s very national interests, and the means to advance them, must therefore be divined de nova, if not ex nihilo, in a quarrelsome cacophony of internationalists, economic nationalists, unilateralists, multilateralists, and neo-isolationists. On the one hand, we read that for the frost time in over fifty years, no serious threat to U.S. security exists. On the other, we read that every global trend poses a long-term threat, be it disease and famine, ecological damage, drugs, pollution, ethnic strife, religious zealotry, terrorism, nuclear proliferation, or economic competition. Nowhere in the planning documents of the secretary of defense or Joint Chiefs of Staff do we read about potential threats from the former Soviet Union or China. No foundation supports research on potential great power conflicts; indeed, foundations seem to have lost interest in strategic affairs altogether. It seems that the Clinton administration and the foreign policy community in the United States are content to wonder only how much and how quickly the ranks of market democracy will be enlarges as a matter of historical inevitability, not how they might be defended in need. The real world, as always, suggests contrary prognostications. To be sure, it is safer now that no Politburo controls a four-million-man military armed with more modem weaponry than the rest of the world combined. Yet, we have no assurance that warlike tendencies will not recapture the former Soviet empire, no assurance that China will not succumb to territorial ambitions as its strength grows, and (if Bosnia is any indication) we have every assurance that Europe is less likely, not more, to stand up to a future Russian bid to intimidate. And what of ourselves? As our military shrinks, as we look increasingly inward, as the blunders of the current and former administrations sour the American people on foreign engagements, what is the chance that the United States will act with prescience and determination to nip future threats in the bud? And if we do not, in the face of new Russian or Chinese challenges, what will become
Role of morphine maintenance dose in the development of tolerance and its attenuation by an NMDA receptor antagonist

Rationale: Current research shows that N-methyl-d-aspartate (NMDA) receptor antagonists attenuate the development of morphine tolerance in rodent antinociceptive assays. Objective: The purpose of this study was to determine the role of morphine maintenance dose in the attenuation of morphine tolerance by the competitive NMDA receptor antagonist, LY235959. Methods: A rat warm-water tail-withdrawal procedure was used to measure the antinociceptive effects of morphine and LY235959. In this procedure, the distal 8 cm of each rat’s tail is immersed in 40° (non-noxious) and 55°C (noxious) water, and the latency to remove the tail is recorded. Results: Morphine (0.3–10 mg/kg, SC) produced dose-dependent increases in tail-withdrawal latencies from the 55°C water. Following determination of the morphine dose-effect curves, rats were administered chronically one of three doses of morphine (10, 20, or 40 mg/kg) either alone or in combination with LY235959 (1.0, 3.0, or 5.6 mg/kg, SC) twice daily for 7 days. Chronic administration of 10, 20, and 40 mg/kg morphine produced rightward shifts in the morphine dose-effect curves of approximately 3-, 6-, and 12-fold, respectively. When LY235959 (1.0–5.6 mg/kg) was co-administered with 10 mg/kg morphine, the development of morphine tolerance was attenuated in a dose-dependent manner, with complete prevention observed following 3.0 mg/kg LY235959. LY235959 (1.0, 3.0 mg/kg) also attenuated the development of tolerance to 20 and 40 mg/kg morphine; however, tolerance was not completely prevented. Administering 3.0 mg/kg LY235959 along with 20 and 40 mg/kg morphine was functionally equivalent to treating rats with half the amount of morphine. Conclusion: These data suggest that the maintenance dose of morphine, and thus the magnitude of tolerance, can determine the effectiveness of an NMDA receptor antagonist to attenuate morphine tolerance.
The Price-Form as a Fractional Reflection of the Aggregate Value of Commodities

The new interpretation of the labor theory of value has raised awareness among Marxist economists that the value of money must be incorporated in a coherent manner into any solution that is proposed to the long-standing transformation problem. The author proposes a fiat money form of value that extends Marx's theory of money and offers a new approach to the transformation procedure based on a reinterpretation of socially necessary abstract labor time.