cssi/SciSciGPT-SciSciNet huggingface dataset:
Probing renormalization group flows using entanglement entropy

In this paper we continue the study of renormalized entanglement entropy introduced in [1]. In particular, we investigate its behavior near an IR fixed point using holographic duality. We develop techniques which, for any static holographic geometry, enable us to extract the large radius expansion of the entanglement entropy for a spherical region. We show that for both a sphere and a strip, the approach of the renormalized entanglement entropy to the IR fixed point value contains a contribution that depends on the whole RG trajectory. Such a contribution is dominant, when the leading irrelevant operator is sufficiently irrelevant. For a spherical region such terms can be anticipated from a geometric expansion, while for a strip whether these terms have geometric origins remains to be seen.
Gender and Organizational Performance: Determinants of Small Business Survival and Success

In this study, we examined several hypotheses on how the survival and success of small businesses headed by men and women are related to industry differences, organizational structures, and attribu...
A Minkowski-style theorem for focal functions of compact convex reflectors

AbstractThis paper 1 continues the study of a class of compact convex hypersurfaces inR n+1 , n ≥ 1, which are boundaries of compact convex bodies obtained by takingthe intersection of (solid) confocal paraboloids of revolution. Such hypersurfaces arecalled reﬂectors. In R 3 reﬂectors arise naturally in geometrical optics and are used indesign of light reﬂectors and reﬂector antennas. They are also important in renderingproblems in computer graphics.The notion of a focal function for reﬂectors plays a central role similar to that ofthe Minkowski support function for convex bodies. In this paper the basic question ofwhen a given function is a focal function of a convex reﬂector is answered by estab-lishing necessary and suﬃcient conditions. In addition, some smoothness properties ofreﬂectors and of the associated directrix hypersurfaces are also etablished. 1 Introduction A convex reﬂector is a convex hypersurface which is the boundary of a compact convexbody in Euclidean space R n+1 ,n≥ 1,obtained by taking the intersection of a given set ofconfocal (solid) paraboloids of revolution. Convex reﬂectors arise naturally as solutions to
Temporal and Convective Inertia Effects in Plain Journal Bearings With Eccentricity, Velocity and Acceleration

This paper extends the theory originally developed by Tichy (Tichy and Bou-Said, 1991, Hydrodynamic Lubrication and Bearing Behavior With Impulsive Loads,” STLE Tribol. Trans. 34 , pp. 505–512) for impulsive loads to high reduced Reynolds number lubrication. The incompressible continuity equation and Navier-Stokes equations, including inertia terms, are simplified using an averaged velocity approach to obtain an extended form of short bearing Reynolds equation which applies to both laminar and turbulent flows. A full kinematic analysis of the short journal bearing is developed. Pressure profiles and linearized stiffness, damping and mass coefficients are calculated for different operating conditions. A time transient solution is developed. The change in the rotor displacements when subjected to unbalance forces is explored. Several comparisons between conventional Reynolds equation solutions and the extended Reynolds number form with temporal inertia effects are presented and discussed. In the specific cases considered in this paper, the primary conclusion is that the turbulence effects are significantly more important than inertia effects.
Kinetically and thermodynamically controlled syntheses of covalent molecular capsules

Abstract It appears that the methods of kinetic/thermodynamic templation have become generally accepted for obtaining covalent molecular capsules. Nowadays, one can thus utilize computational chemistry for designing concave frameworks and then employ a proper templating agent for optimizing the synthesis. Moreover, there seems to be a considerable potential toward investigating thermodynamic equilibration of reacting compounds for obtaining large molecular cages. In line with recent developments in the field, our review delineates kinetics and thermodynamics of chemical reactions that are typically used in the synthesis of molecular hosts and, in particular, molecular capsules. Concave hosts hold promise as a potent reaction/encapsulation medium for catalytic, sensing or delivery applications so that developing and understanding the basis of new methods for the effective synthesis of such structures is important.
Engaging Conflict History: Toward an Integrated Method of Conflict Resolution Dialogue and Capacity Building

This article presents a method of applied practice that engages contested historical meanings of intercommunal and international conflict. The concept of conflict history is introduced to describe a worldview of a conflict-affected community that seeks a coherent explanation of the origin, evolution, and significance of the conflict it faces. Four interconnected perspectives on conflict history–orthodox, different, mediative, and alternative–are explored to bridge empirical inquiry into the divided past with possibilities of future coexistence. The study builds on psychoanalysis and memory research, as well as on the author's experience in conflict resolution dialogues across the Taiwan Strait.
Fluctuation effects on microphase separation in random copolymers

We study random copolymers consisting of two kinds of monomers, with attraction between similar kinds. The mean-field analysis of this system indicates a continuous phase transition into a phase with periodic microdomain structure. It is shown that the inverse of the renormalized propagator has a minimum at non-zero wavenumbers. Consequently, there is an anomalously large contribution of fluctuations that make the disordered phase locally stable at every finite temperature. However, below a certain temperature, the ordered phase is shown to be locally stable and a weak first-order transition is possible, similar to the weak crystallization theory developed by Brazovskii.
Is the missing ultra-red material colorless ice?

The extremely red colors of some transneptunian objects and Centaurs are not seen among the Jupiter family comets which supposedly derive from them. Could this mismatch result from sublimation loss of colorless ice? Radiative transfer models show that mixtures of volatile ice and non-volatile organics could be extremely red, but become progressively darker and less red as the ice sublimates away.
A new approach to searching for dark matter signals in Fermi-LAT gamma rays

Several cosmic ray experiments have measured excesses in electrons and positrons, relative to standard backgrounds, for energies from ~ 10 GeV–1 TeV. These excesses could be due to new astrophysical sources, but an explanation in which the electrons and positrons are dark matter annihilation or decay products is also consistent. Fortunately, the Fermi-LAT diffuse gamma ray measurements can further test these models, since the electrons and positrons produce gamma rays in their interactions in the interstellar medium. Although the dark matter gamma ray signal consistent with the local electron and positron measurements should be quite large, as we review, there are substantial uncertainties in the modeling of diffuse backgrounds and, additionally, experimental uncertainties that make it difficult to claim a dark matter discovery. In this paper, we introduce an alternative method for understanding the diffuse gamma ray spectrum in which we take the intensity ratio in each energy bin of two different regions of the sky, thereby canceling common systematic uncertainties. For many spectra, this ratio fits well to a power law with a single break in energy. The two measured exponent indices are a robust discriminant between candidate models, and we demonstrate that dark matter annihilation scenarios can predict index values that require ``extreme'' parameters for background-only explanations.
“A Logic of Camps”: French Antiracism as Competitive Nationalism

As the Charlie Hebdo and Copenhagen attacks starkly remind us, European multicultural policy continues to falter over the growth of public Islam. But long before these events, tension between competing visions of citizenship and nationhood had weakened the very civil society organizations that could shape such policy. In France, where non-governmental organizations had labored against discrimination for over a century, this conflict led to profound disaffection within the nation's powerful antiracism movement. Drawing from more than two years of ethnographic fieldwork among French antiracist NGOs, this article examines that disaffection among activists whose work in the name of cultural outsiders simultaneously served to rememorialize historic national traumas from the Dreyfus Affair to Algeria. Revealing a new despondency over sociolegal advocacy for Islam, some decried “infiltration” of communitarian voices into their erstwhile republican movement while others, under increasing pressure to adopt an emergent pluralist vision, equated this new model with foreignness itself. The resulting “crisis of antiracism” saw competitive reassertions of nationhood in the face of countervailing state discourses of European postnationalism. If writings on French multiculturalism to date have focused on Islamic piety and urban youth deviance, this article examines the significant impact these have had on France's preeminent social justice movement.
A property of matrices with positive determinants

Abstract Let P be the set of all n × n real matrices which have a positive determinant. We show here that at least 2n − 1 matrices are needed to “see” each matrix in P . Also, any finite subset of P can be “seen” from a class of at most 2n − 1 matrices in P .
Simultaneous Adaptation of Echo Cancellation and Spectral Subtraction for In-Car Speech Recognition

Recently, automatic speech recognition in a car has practical uses for applications like car-navigation and hands-free telephone dialers. For noise robustness, the current successes are based on the assumption that there is only a stationary cruising noise. Therefore, the recognition rate is greatly reduced when there is music or news coming from a radio or a CD player in the car. Since reference signals are available from such in-vehicle units, there is great hope that echo cancellers can eliminate the echo component in the observed noisy signals. However, previous research reported that the performance of an echo canceller is degraded in very noisy conditions. This implies it is desirable to combine the processes of echo cancellation and noise reduction. In this paper, we propose a system that uses echo cancellation and spectral subtraction simultaneously. A stationary noise component for spectral subtraction is estimated through the adaptation of an echo canceller. In our experiments, this system significantly reduced the errors in automatic speech recognition compared with the conventional combination of echo cancellation and spectral subtraction.
A deformation of commutative polynomial algebras in even numbers of variables

We introduce and study a deformation of commutative polynomial algebras in even numbers of variables. We also discuss some connections and applications of this deformation to the generalized Laguerre orthogonal polynomials and the interchanges of right and left total symbols of differential operators of polynomial algebras. Furthermore, a more conceptual re-formulation for the image conjecture [18] is also given in terms of the deformed algebras. Consequently, the well-known Jacobian conjecture [8] is reduced to an open problem on this deformation of polynomial algebras.
On some variations of two-way probabilistic finite automata models

Rabin [M. Rabin, Probabilistic finite automata, Information and Control (1963) 230-245] initiated the study of probabilistic finite automata (pfa). Rabin's work showed a crucial role of the gap in the error bound (for accepting and non-accepting computations) in the power of the model. Further work resulted in the identification of qualitatively different error models (one-sided error, bounded and unbounded errors, no error etc.) Karpinski and Verbeek [M. Karpinski, R. Verbeek, There is no polynomial deterministic simulation of probabilistic space with two-way random-tape generator, Information and Control 67 (1985) 158-162] and Nisan [N. Nisan, On read-once vs. multiple access to randomness in logspace, in: Proc. of Fifth IEEE Structure in Complexity Theory, Barcelona, Spain, 1990, pp. 179-184] studied a model of probabilistic automaton in which the tape containing random bits can be read by a two-way head. They presented results comparing models with one-way vs. two-way access to randomness. Dwork and Stockmeyer [C. Dwork, L. Stockmeyer, Interactive proof systems with finite state verifiers, IBM Report RJ 6262, 1988] and Condon et al. [A. Condon, et al., On the power of finite automata with both nondeterministic and probabilistic states, SIAM Journal on Computing (1998) 739-762] studied a model of 2-pfa with nondeterministic states (2-npfa). In this paper, we present some results about the above mentioned variations of probabilistic finite automata, as well as a model of 2-pfa augmented with a pebble studied in [B. Ravikumar, Some observations on two-way probabilistic finite automata, in: Proc. of the Foundations of Software Technology and Theoretical Computer Science, 1992, pp. 392-403]. Our observations indicate that these models exhibit subtle variations in their computational power. We also mention many open problems about these models. Complete characterizations of their power will likely provide deeper insights about the role of randomness in space-bounded computations.
An analysis of scripts generated in writing between users and computer consultants

The scripts generated in written interactive communications between users and a computer consultant program were investigated in a controlled experiment. The program was a simulation of UC, the UNIX Consultant, which users believed to be the actual program. An analysis of the scripts generated while solving a predefined set of problems showed the heavy use of context in forms such as ellipsis, anaphora, indirect speech acts, and grammatically incomplete sentences in over one-quarter of input clauses. Also present were grammatically ill-formed constructions and spelling errors. A comparison with a control group of users solving the same problem set with human consultants showed that the control group relied on context about twice as much as the simulation group. This suggests that people naturally use context in language and that the simulation group tried to rely less on context because they believed that they were speaking to a computer. Even so, contextual information is essential to understanding a large part of the simulation group's input.
Cyclopentenones and cyclopentanones from the reactions of vinyl vicinal tricarbonyls with carbon nucleophiles

Abstract Vinyl vicinal tricarbonyls undergo tandem addition of Wittig reagents or compounds containing activated methylene groups to form highly functionalized derivatives of cyclopentenones or cyclopentanones.
Spatial coherence properties of monochromatic electromagnetic beams and of laser modes

It is shown that, contrary to common belief, monochromatic light beams are, in general, not spatially completely coherent, i.e., they will, in general, not produce fringes of unit visibility in a Young's double pinhole interference experiment. We cite experiments with laser modes which confirm this result.
The computing research repository: promoting the rapid dissemination and archiving of computer science research

We describe the Computing Research Repository (CoRR), a new electronic archive for rapid dissemination and archiving of computer science research results. CoRR was initiated in September 1998 through the cooperation of ACM, LANL (Los Alamos National Laboratory) e-Print archive, and NCSTRL (Networked Computer Science Technical Research Library. Through its implementation of the Dienst protocol, CoRR combines the open and extensible architecture of NCSTRL with the reliable access and well-established management practices of the LANL XXX e-Print repository. This architecture will allow integration with other e-Print archives and provides a foundation for a future broad-based scholarly digital library. We describe the decisions that were made in creating CoRR, the architecture of the CoRR/NCSTRL interoperation, and issues that have arisen during the operation of CoRR.
ABUNDANCES OF GALACTIC ANTICENTER PLANETARY NEBULAE AND THE OXYGEN ABUNDANCE GRADIENT IN THE GALACTIC DISK

We have obtained spectrophotometric observations of 41 anticenter planetary nebulae (PNe) located in the disk of the Milky Way. Electron temperatures and densities, as well as chemical abundances for He, N, O, Ne, S, Cl, and Ar were determined. Incorporating these results into our existing database of PN abundances yielded a sample of 124 well-observed objects with homogeneously determined abundances extending from 0.9 to 21 kpc in galactocentric distance. We performed a detailed regression analysis which accounted for uncertainties in both oxygen abundances and radial distances in order to establish the metallicity gradient across the disk to be 12 + log(O/H) = (9.09 ± 0.05) – (0.058 ± 0.006) × Rg , with Rg in kpc. While we see some evidence that the gradient steepens at large galactocentric distances, more objects toward the anticenter need to be observed in order to confidently establish the true form of the metallicity gradient. We find no compelling evidence that the gradient differs between Peimbert Types I and II, nor is oxygen abundance related to the vertical distance from the galactic plane. Our gradient agrees well with analogous results for H II regions but is steeper than the one recently published by Stanghellini & Haywood over a similar range in galactocentric distance. A second analysis using PN distances from a different source implied a flatter gradient, and we suggest that we have reached a confusion limit which can only be resolved with greatly improved distance measurements and an understanding of the natural scatter in oxygen abundances.
Early Lukács, Aesthetics of Politics?

This article explores the unique status accorded to aesthetics in Gyorgy Lukacs’s work, with particular focus on his Heidelberg writings of the 1910s, and their thematic echoes in Lukacs’s late Aesthetics, straddling the shift in Lukacs’s philosophical framework from neo-Kantianism and Weberianism to Hegelian Marxism. It suggests that these writings, discovered after Lukacs’s death and still marginal to scholarship on the Hungarian thinker, provide a singular illumination on many of the leitmotivs of Lukacs’s oeuvre. In particular, the essay considers the shapes taken in these early writings by the subject-object dialectic and the concept of form, as well as the foreshadowings of Lukacs’s theories of ideology and standpoint.
Current status of asteroseismology

Abstract Asteroseismology, the extension of helioseismology to stars – solar-alike or not – has been an exciting and active field of research for about two decades. While over that period helioseismology has had great success in revealing the solar structure and its dynamics, progress in asteroseismology has been hampered by the observational challenge to carry out, primarily from the ground, high precision measurements on unresolved objects with a substantially lower flux. Over the past years, the field has seen a new golden age, primarily driven by observational advances and opportunities. With the June 2003 launch of the MOST spacecraft and the highly anticipated December 2006 launch of the COROT mission, we have truly entered the space-based observational era of asteroseismology. The ambitious vision mission like the Stellar Imager might even one day allow us to spatially resolve oscillations on not too distant stars. At the same time ground-based observations have recently seen a quantum leap in precision thanks to the synergy between asteroseismology and exo-planet detection which both rely primarily on precise radial velocity techniques. The diagnostic potential of asteroseismology is clearly demonstrated by the wealth of inferences collected from helioseismology. Nevertheless the current status of observations, their interpretations and their implications for our models remain hotly debated subjects. I review the status of the field, with an emphasis on solar-like targets, while incorporating my own healthy scepticism and observational bias.
Dynamics of International Debt Overhang with Two Lender Banks

This paper presents a dynamic formalization of the behaviour of creditor banks on the secondary market for debts. I formulate the problem as an infinite-horizon game with two banks as players where each bank decides in every period either to sell its loan exposure to the debtor country at the present secondary market price, or to wait and keep its exposure to the next period. There exist three types of subgame-perfect equilibria with the property called the time continuation. I consider the relation ship between our equilibria and those of the Kaneko–Prokop (1993) one-period approach to the same problem and show that their approach does not lose much of the dynamic nature of the problem. In any equilibrium of the game, each bank waits in every period with high probability. I discuss the implications of these results for the long-run behaviour of banks on the secondary market and the resolution of debt overhang JEL Classification Number: F34
Predicting disease progression after regional therapy for in-transit melanoma

Importance Although approximately 30% to 50% of patients experience a complete response after regional chemotherapy for in-transit melanoma, a subset of patients will develop rapidly progressive disease. In the current era of an expanding armamentarium, including both regional and systemic options for treating advanced melanoma, identifying perioperative factors that predict disease progression may obviate unnecessary morbidity associated with regional therapy and avoid delays in systemic therapy. Objective To identify patient-related clinical and pathological variables, as well as procedural factors, that correlate with disease progression. Design Using a prospectively maintained database, we identified patients who either underwent first-time melphalan-based isolated limb infusion (ILI) or first-time hyperthermic isolated limb perfusion (HILP) for in-transit melanoma. Response was defined using modified Response Evaluation Criteria in Solid Tumors for cutaneous disease at 3 months after treatment. Survival analyses were performed using the Kaplan-Meier method, with the differences in survival curves compared using a log-rank test. Potential preoperative and procedural predictors of in-field progressive disease were analyzed using logistic regression. Participants Of the 258 patients included in the database, 215 were identified as having undergone first-time regional therapy. Of these 215 patients, 134 underwent ILI, and 81 underwent HILP. Exposure Regional therapy (ILI or HILP). Main Outcomes and Measures Complete response or progressive disease. Results Of 134 patients who underwent ILI, 43 (32.1%) experienced in-field progressive disease. Of 81 patients who underwent HILP, 9 (11.1%) experienced in-field progressive disease. The median survival for patients with in-field progressive disease was 20.3 months for the ILI cohort and 15.0 months for the HILP cohort. In general, patients with progressive disease were younger, with advanced-stage melanoma and increased tumor burden. Compared with patients who experienced a complete response, patients with in-field progressive disease after ILI were younger (odds ratio, 1.06 [95% CI, 0.90-0.98]; P = .002). For patients who underwent HILP, no clinically relevant preoperative predictors of in-field progressive disease were identified. Procedural variables, including chemotherapeutic dosing, degree of acidosis or base deficit achieved, and peak temperature attained, were not predictors of in-field progressive disease after ILI or HILP. Conclusions and Relevance Patient, clinical, and procedural factors are unreliable predictors of in-field progressive disease after regional therapy in patients with in-transit melanoma. Defining the potential utility of molecular markers in predicting response or failure of regional therapy should be the focus of future research efforts.
The pathogen transmission avoidance theory of sexual selection

Abstract The current theory that sexual selection results from female preference for males with good genes suffers from several problems. An alternative explanation, the pathogen transmission avoidance hypothesis, argues that the primary function of showy traits is to provide a reliable signal of current disease status, so that sick individuals can be avoided during mating. This study shows that a significant risk of pathogen transmission occurs during mating and that showy traits are reliable indicators of current disease status. A simulation model of population dynamics linked with pathogen transmission indicates that female choosiness traits are selectively advantageous and spread through the population but because the selective benefit of choosiness depends on the percentage of choosy females and bright males, as sexual selection proceeds the selection pressure is reduced and the process becomes self-limiting rather than runaway. Thus, an epidemic model approach leads to very different conclusions than a constant selection-coefficient population genetic approach. The origin of female choosiness is argued to lie in a general tendency to avoid sick individuals, even in the absence of showy traits, which originate as exaggerations of normal traits that are indicative of good health (bright feathers, vigorous movement, large size). Thus, in this new model the origins of both showy traits and female choosiness are not problematic and there is no threshold effect. This model predicts that when the possession of male showy traits does not help to reduce disease in the female, showy traits are unlikely to occur. This case corresponds to thorough exposure of every animal to all group pathogens, on average, in large groups. Such species are shown with a large data set on birds to be less likely to exhibit showy traits. The good-genes model does not make this prediction. The pathogen transmission avoidance model can also lead to the evolution of showy traits even when selection is not effective against a given pathogen (e.g. when there is no heritable variation for resistance), but can result in selection for resistance if such genes are present. Monogamy is argued to reduce selection pressures for showy traits; data show monogamous species to be both less parasitized and less showy. Overall, the pathogen transmission avoidance hypothesis provides a complete alternative to the good-genes theory and makes new predictions.
Internal Three-Dimensional Viscous Flow Solution Using the Streamlike Function

On presente une methode pour la resolution des equations de Navier-Stokes elliptiques tridimensionnelles, basee sur la formulation fonction de courant-vorticite
Structural Parameters and Dynamical Masses for Globular Clusters in M33

Using high-dispersion spectra from the HIRES echelle spectrograph on the Keck I telescope, we measure velocity dispersions for four globular clusters (GCs) in M33. Combining the velocity dispersions with integrated photometry and structural parameters derived from King-Michie model fits to Wide Field Planetary Camera 2 images, we obtain mass-to-light ratios for the clusters. The mean value is M/LV = 1.53 ± 0.18, very similar to the M/LV of Milky Way and M31 GCs. The M33 clusters also fit very well into the fundamental plane and binding energy–luminosity relations derived for Milky Way GCs. Dynamically and structurally, the four M33 clusters studied here appear virtually identical to Milky Way and M31 GCs.
Statistical exploration of fragmentation phase space and source sizes in nuclear multifragmentation

Abstract The multiplicity distributions for individual fragment Z values in nuclear multifragmentation are characterized by their maximum value m Z . A strong indication of statistical coverage of fragmentation phase space is inferred from the dependence m Z = Z 0 / Z , where Z 0 is the source size. The source sizes coincide with those extracted from the analysis of fixed multiplicity charge distributions.
A grassmannian étude in NMHV minors

Arkani-Hamed, Cachazo, Cheung and Kaplan have proposed a Grassmannian formulation for the S-matrix of \( \mathcal{N} = 4 \) Yang-Mills as an integral over link variables. In parallel work, the connected prescription for computing tree amplitudes in Witten’s twistor string theory has also been written in terms of link variables. In this paper we extend the six-and seven-point results of arXiv:0909.0229 and arXiv:0909.0499 by providing a simple analytic proof of the equivalence between the two formulas for all tree-level NMHV superamplitudes. Also we note that a simple deformation of the connected prescription integrand gives directly the ACCK Grassmannian integrand in the limit when the deformation parameters equal zero.
A new synthesis of α-arylglycines from aryl boronic acids

Abstract Aryl and heteroaryl boronic acids react with the adducts of amines and glyoxylic acid to give the corresponding α-aryl and α-heteroaryl glycine derivatives. Several examples of this reaction with m - and p -substituted aryl boronic acids as well as 3-thienyl, 2-thienyl, 2-furyl, 2-benzo[b]furyl and 2-benzo[b]thienyl boronic acids are described.
Capacity Limit of the Noiseless, Energy-Efficient Optical PPM Channel

The energy-efficient capacity of the noiseless optical PPM channel is examined. It is shown that, although the capacity per photon can be made to increase without bound, the capacity per channel use (for best energy efficiency) is always less than 2 nats and approaches 2 nats/symbol as the bandwidth expansion factor goes to infinity.
Adjacent-channel interference in frequency-hopping ad hoc networks

This paper considers ad hoc networks that use the combination of coded continuous-phase frequency-shift keying (CPFSK) and frequency-hopping multiple access. Although CPFSK has a compact spectrum, some of the signal power inevitably splatters into adjacent frequency channels, thereby causing adjacent-channel interference (ACI). The amount of ACI is controlled by setting the fractional in-band power; i.e., the fraction of the signal power that lies within the band of each frequency channel. While this quantity is often selected arbitrarily, a tradeoff is involved in the choice. This paper presents a new analysis of frequency-hopping ad hoc networks that carefully incorporates the effect of ACI. The analysis accounts for the shadowing, Nakagami fading, CPFSK modulation index, code rate, number of frequency channels, fractional in-band power, and spatial distribution of the interfering mobiles. Expressions are presented for both outage probability and transmission capacity. With the objective of maximizing the transmission capacity, the optimal fractional in-band power that should be contained in each frequency channel is identified.
Excitation of creeping waves on a circular cylinder with a thick dielectric coating

A magnetic line source on a dielectric coated conducting cylinder excites a creeping wave field. The coating is not necessarily thin, so more than one mode can exist. It is found that as the coating thickness is increased, the surface field on the dielectric-air interface exhibits a distinctive beat pattern resulting from the interaction between two creeping-wave modes.
Dielectric relaxation of acetonitrile and propionitrile in benzene and carbon tetrachloride solutions

Abstract Dielectric permittivities and losses have been measured at wavelengths of 3 × 104, 15.0, 10.0, 3.23, 1.95, 1.25, 0.60, and 0.40 cm at various temperatures between 24° and 60° C for benzene and carbon tetrachloride solutions of acetonitrile and propionitrile. The far-infrared spectra in the range of 10–150 cm−1 of dilute solutions of both the nitriles have been investigated. The effect of the far-infrared absorptions on the microwave data has been discussed. A single relaxation time has been obtained for acetonitrile at each temperature whereas the dielectric data of propionitrile have been analyzed in terms of two coupled relaxation processes. The thermodynamic parameters for dielectric relaxation and viscous flow have been reported.
Design, Synthesis and Characterization of Cationic Peptide and Steroid Antibiotics

Novel cationic antibiotics have been developed to mimic the cationic, facial amphiphilic structures of naturally occurring peptide antibiotics. Several series of designed peptide antibiotics have been reported, as well as examples based on β-peptides and steroids. The antibacterial activities of these compounds are derived from the disruption and/or permeabilization of bacterial membranes, and many display potent antibacterial activity and selectivity for bacterial cells. These antibiotics may prove valuable in combating bacterial infections, especially those from drug-resistant organisms.
Exploring Epigenetic Regulation of Fear Memory and Biomarkers Associated with Post-Traumatic Stress Disorder

This review examines recent work on epigenetic mechanisms underlying animal models of fear learning as well as its translational implications in disorders of fear regulation, such as Post-traumatic Stress Disorder (PTSD). Specifically, we will examine work outlining roles of differential histone acetylation and DNA-methylation associated with consolidation, reconsolidation, and extinction in Pavlovian fear paradigms. We then focus on the numerous studies examining the epigenetic modifications of the Brain-derived neurotrophin factor (BDNF) pathway and the extension of these findings from animal models to recent work in human clinical populations. We will also review recently published data on FKBP5 regulation of glucocorticoid receptor function, and how this is modulated in animal models of PTSD and in human clinical populations via epigenetic mechanisms. As glucocorticoid regulation of memory consolidation is well established in fear models, we examine how these recent data contribute to our broader understanding of fear memory formation. The combined recent progress in epigenetic modulation of memory with the advances in fear neurobiology suggest that this area may be critical to progress in our understanding of fear-related disorders with implications for new approaches to treatment and prevention.
Wilson Renormalization Group Analysis of Theories with Scalars and Fermions

Abstract The continuous block-spin (Wilson) renormalization-group equation governing the scale dependence of the action is constructed for theories containing scalars and fermions. A locally approximated form of this equation detailing the structure of a generalized effective potential is numerically analyzed. The role of the irrelevant operators in the nonperturbative renormalization group running is elucidated and a comparison with the one-loop perturbative results is drawn. Focusing on the spontaneously broken phase of a model possessing a discrete symmetry forbidding an explicit fermion mass term, mass bounds on both the scalar and fermion degrees of freedom are established. The effect of the generalized Yukawa coupling on the scalar mass upper bound is emphasized.
Secure Cooperative Regenerating Codes for Distributed Storage Systems

Regenerating codes enable trading off repair bandwidth for storage in distributed storage systems (DSS). Due to their distributed nature, these systems are intrinsically susceptible to attacks, and they may also be subject to multiple simultaneous node failures. Cooperative regenerating codes allow bandwidth efficient repair of multiple simultaneous node failures. This paper analyzes storage systems that employ cooperative regenerating codes that are robust to (passive) eavesdroppers. The analysis is divided into two parts, studying both minimum bandwidth and minimum storage cooperative regenerating scenarios. First, the secrecy capacity for minimum bandwidth cooperative regenerating codes is characterized. Second, for minimum storage cooperative regenerating codes, a secure file size upper bound and achievability results are provided. These results establish the secrecy capacity for the minimum storage scenario for certain special cases. In all scenarios, the achievability results correspond to exact repair, and secure file size upper bounds are obtained using min-cut analyses over a suitable secrecy graph representation of DSS. The main achievability argument is based on an appropriate precoding of the data to eliminate the information leakage to the eavesdropper.
Wage Hunters and Gatherers: Search for Work in the Urban and Rural Economy of South Gujarat

This collection of essays focuses on a large segment of unskilled labourers in Indian society who have failed to manage regular and protected employment in the rapidly expanding towns and cities of Third World countries. Based on empirical research over two decades in a small town of south Gujarat, the author discusses and then rejects some of the standard notions regarding the origin, size, shape and growth of this sector of the Indian population.
The Dimensions of Tacit & Explicit Knowledge: A Description and Measure

Knowledge workers are often employed to extract knowledge from domain experts in order to codify knowledge held by these experts. The extent to which workers rely on tacit or explicit knowledge may produce inefficiencies and reduce productivity if the information is not shared among those who need it or it encapsulates strategic goals and is inadvertently shared with those who might undermine the firm's competitive advantage. This paper discusses the nature of tacit versus explicit knowledge in terms of the dimensions thought to contribute to its degree of tacitness. We present an instrument designed to elicit perceptions regarding the nature of knowledge used by workers and their degree of reliance on tacit knowledge. Use of this instrument by managers would help them identify pockets of tacit knowledge within the firm that could either be made explicit so that other workers can benefit from it or prevented from becoming explicit should its strategic value require protection
Effect of Cesium Modification of Silica-Supported Vanadium-Oxide Catalysts in Butane Oxidation

Abstract The effect of Cs modification in the selective oxidation of butane at 520°C was studied over SiO2-supported catalysts containing about 6 or 0.6 wt% vanadium atoms using a butane/oxygen/helium mixture of 4/8/88. Dehydrogenation products (unsaturated C4′s) and carbon oxides were the primary products. For the supported sample of high vanadium loading where a significant amount of vanadium existed as V2O5 crystallites under reaction conditions, Cs modification significantly increased the selectivity for dehydrogenation and decreased the extent of reduction of the vanadium oxide crystallites in the reaction mixture, but had only small effects on the activation energy or rate of reaction. Unsupported V2O5 catalysts modified by Cs at a Cs/V ratio of 0.023 also showed enhanced dehydrogenation selectivity, a lower degree of reduction at steady state, and a significantly different temperature-programmed reduction profile. Cs was found to be segregated on the surface of the crystallites. For the supported samples of low vanadium loading, Cs modification decreased the intensity of the Raman peak that was indicative of highly dispersed vanadia species and increased the activation energy of the reaction. These data were consistent with the picture that Cs modification enhanced the formation of vanadia clusters on the support.
Memory models: a case for rethinking parallel languages and hardware

The era of parallel computing for the masses is here, but writing correct parallel programs remains a challenge--popular parallel environments offer no analogs for the concepts of structured and safe sequential programming. The memory model forms the heart of the concurrency semantics of any (shared-memory) parallel language or hardware. Unfortunately, it has involved a tradeoff between programmability and performance, and has arguably been one of the most challenging and contentious areas in shared-memory specification. Recent broad community-scale efforts have finally led to a convergence in this debate, with popular languages such as Java and C++ and most hardware vendors publishing compatible memory model specifications. Although this convergence is a dramatic improvement, it has exposed fundamental shortcomings in current popular languages and systems that prevent achieving the vision of structured and safe parallel programming.I will discuss the path to the above convergence, the hard lessons learned, and their implications. A cornerstone of this convergence has been the view that the memory model should be a contract between the programmer and the system--if the programmer writes well-structured (data-race-free) programs, the system will provide high programmability (sequential consistency) and performance. I will discuss why this view is the best we can do with current popular languages, and why it should be unacceptable moving forward. I will then discuss research directions that eliminate worrying about the memory model, but require rethinking popular parallel languages and hardware. In particular, I will argue for languages that eliminate data races by design and provide determinism by default, while retaining the advantages of modern object-oriented programming. I will also argue for hardware that takes advantage of such disciplined programming models to enable energy-efficient performance scalability. I will use the Deterministic Parallel Java language and DeNovo hardware projects at Illinois as examples of such directions.
Invariant measures on the space of horofunctions of a word hyperbolic group

We introduce a natural equivalence relation on the space $\sH_0$ of horofunctions of a word hyperbolic group that take the value 0 at the identity. We show that there are only finitely many ergodic measures that are invariant under this relation. This can be viewed as a discrete analog of the Bowen-Marcus theorem. Furthermore, if $\eta$ is such a measure and $G$ acts on a space $(X,\mu)$ by p.m.p. transformations then $\eta \times \mu$ is virtually ergodic with respect to a natural equivalence relation on $\sH_0\times X$. This is comparable to a special case of the Howe-Moore theorem. These results are applied to prove a new ergodic theorem for spherical averages in the case of a word hyperbolic group acting on a finite space.
Predicting the distribution of households and employment: a seemingly unrelated regression model with two spatial processes

Abstract Household and employment counts (by type) are key inputs to models of travel demand and air quality. For a variety of reasons, spatial dependence is very likely present in and across these counts. In order to identify the nature of these unobserved relationships, this study provides the first application of a feasible generalized spatial 3SLS estimation procedure for a seemingly unrelated regression (SUR) model with two spatial processes. Statistical tests reveal that this more generalized model is superior to its constrained versions (e.g., SUR models without spatial components or with just a spatial lag or spatial error process). In the resulting model of Austin, Texas data, local land-use conditions offer substantial predictive power of household and job densities, and transportation access plays a role, as anticipated. The work demonstrates that SUR estimation of land-use intensities from parcel-level data with two types of spatial dependence is feasible and meaningful. Coupled with an upstream model of land-use type, this work offers key inputs for travel demand analyses, with transportation system performance feedback.
Learning and complexity in genetic auto-adaptive systems

Abstract We describe and investigate the learning capabilities displayed by a population of self-replicating segments of computer code subject to random mutation: the tierra environment. We find that learning is achieved through phase transitions that adapt the population to the environment it encounters, at a rate characterized by external parameters such as mutation rate and population size. Our results suggest that most effective learning is achieved close to the transition to disorder, and that learning curves of evolutionary systems are fractal.
Laboratory characterization of the structural properties controlling dynamical gas transport in Mars-analog soils

Dynamical transport of gases within the martian regolith controls many climatic processes, and is particularly important in the deposition and/or mobilization of shallow ground ice, as well as exchange of other volatiles between the martian regolith and atmosphere. A variety of theoretical studies have addressed issues related to ground ice dynamics on Mars and in the terrestrial analog environment of the Antarctic Dry Valleys. These theoretical studies have drawn on a limited set of empirical measurements to constrain the structural parameters controlling gas diffusion and flow in soils. Here, we investigate five groups of Mars-analog soils: glass spheres, JSC Mars-1, aeolian dune sand, Antarctic Dry Valley soils, and arctic loess. We present laboratory measurements of the structural properties most relevant to gas transport in these soils: porosity, tortuosity, permeability, bulk and intrinsic densities, grain-size distribution, pore-size distribution and BET surface area. Our results bear directly both on the appropriateness of assumptions made in theoretical studies and on current outstanding issues in the study of shallow ground ice on Mars and in the Dry Valleys. Specifically, we find that (1) measured values of tortuosity are lower than values commonly assumed for Mars by a factor of two to three; (2) diffusive loss of ground ice on Mars can likely proceed up to four times faster than predicted by theoretical studies; (3) soil permeabilities are sufficiently high that flushing of the soil column by bulk flow of atmospheric gases may further speed loss or deposition of shallow ground ice; (4) the pore volume in some Mars-analog soils is sufficiently high to explain high volumetric ice abundances inferred from Mars Odyssey Gamma Ray Spectrometer data as simple pore ice; and (5) measured properties of soils collected in Beacon Valley, Antarctica agree well with assumptions made in theoretical studies and are consistent with rapid loss of ground ice in the current climate.
Quasisimple classical groups and their complex group algebras

Let H be a finite quasisimple classical group, i.e., H is perfect and S:= H/Z(H) is a finite simple classical group. We prove that, excluding the open cases when S has a very exceptional Schur multiplier such as PSL3(4) or PSU4(3), H is uniquely determined by the structure of its complex group algebra. The proofs make essential use of the classification of finite simple groups as well as the results on prime power character degrees and relatively small character degrees of quasisimple classical groups.
Stereoselectivity in the Hydroboration of C4-C-Methylene Groups

Abstract Conditions for the hydroxylation of an exocyclic methylene group at C4 of a pyranoside ring via hydroboration have been examined with a view to determining the optimum procedure for obtaining the axially-oriented C4-CH2OH group. The regio- and stereochemical outcome of the reactions rely not only on the hydroborating reagent used, but, to a surprising degree, on the nature of the protecting group at the “remote” C6-OH. Silyl ethers are preferred because the only by-product formed is the tertiary alcohol, which can be recycled through dehydration to the starting alkene by treatment with thionyl chloride.