cssi/SciSciGPT-SciSciNet huggingface dataset:
The impact of cosmic dust on supernova cosmology

Extinction by intergalactic grey dust introduces a magnitude redshift-dependent offset in the standard‐candle relation of supernova Type Ia. This leads to overestimated luminosity distances compared to a dust-free universe. Quantifying the amplitude of this systematic effect is crucial for an accurate determination of the dark energy parameters. In this paper, we model the grey dust extinction in terms of the star formation history of the Universe and the physical properties of the dust grains. We focus on a class of cosmic dust models which satisfy current observational constraints. These can produce an extinction as large as 0.08 mag at z = 1.7 and potentially disrupt the dark energy parameter inference from future SN surveys. In particular depending on the dust model, we find that an unaccounted extinction can bias the estimation of a constant dark energy equation of state w by shifting its best-fitting value up to 20 per cent from its true value. Near-IR broad-band photometry will hardly detect this effect, while the induced decrement of the Balmer lines requires high signal-to-noise spectra. Indeed, IR-spectroscopy will be needed for high-redshift SNe. Cosmic dust extinction may also cause a detectable violation of the distance‐duality relation. A more comprehensive knowledge of the physics of the intergalactic medium is necessary for an accurate modelling of intergalactic dust. Due to the large magnitude dispersion current luminosity distance measurements are insensitive to such possible extinction effects. In contrast, these must be taken into account if we hope to disclose the true nature of dark energy with the upcoming generation of SN Ia surveys.
Oscillatory oxidation of CO over Pt at pressures from 10 to 760 torr

Oscillations in the rate of CO oxidation over polycrystalline Pt have been measured at total pressures of 760 and 10 Torr. Despite the pressure change of two orders of magnitude, oscillations occurred between similar values of high and low reactivity, and over roughly the same experimental parameters. The lack of dependence of the reaction kinetics on the pressure is not predicted by the Langmuir-Hinshelwood equations that provide the rate multiplicities underlying the oscillations in a number of recent models. This lack of agreement suggests that the current understanding of CO oxidation and oscillatory reaction kinetics remains incomplete. The primary difference between the oscillations at the two pressures occurred in the waveforms, which were highly structured and fractal-like at P = 760 Torr, and became simple square waves on the evolved catalyst surface at P = 10 Torr. Differences in the catalyst surface structure and in coupling between parts of the catalyst through concentration gradients in the gas may account for these changes in the complexity of the waveforms.
Guided wave approaches to optical bistability

We have analyzed four different guided wave approaches to achieving a power dependent refractive index and optical bistability. These include surface plasmons at the interface between a metal and a semiconductor, symmetric surface plasmon modes guided by thin metal films, conventional single film integrated optics waveguides, and multifilm integrated optics. The relative merits of each geometry are discussed for utilizing the large cubic nonlinearities in the semiconductors GaAs and InSb. Both the mode attenuation and the minimum power required for a nonlinear phase shift of \pi/2 are evaluated numerically and it is shown that usable propagation distances can be obtained, even for highly lossy media such as GaAs.
Chandra Detection of Fe XVII in Absorption: Iron Abundance in the Hot Gaseous Interstellar Medium

The iron depletion level and the gas-phase iron abundance in the hot (~106 K) interstellar medium (ISM) are critical to our understanding of its energy balance as well as the thermal sputtering, cooling, and heating processes of dust grains. Here, we report on the first detection of the Fe XVII absorption line at 15.02 A from the hot ISM in the spectrum of the low-mass X-ray binary 4U 1820-303 observed with the Chandra X-Ray Observatory. By jointly analyzing this absorption line with those from O VII, O VIII, and Ne IX ions in the same spectrum, we obtain an abundance ratio as Fe/Ne = 0.8(0.4, 2.1) in units of the Anders & Grevesse solar value (90% confidence intervals). We find that the result is robust with respect to different assumed gas temperature distributions. The obtained Fe/Ne abundance ratio, albeit with large uncertainties, is consistent with the solar value, indicating that there is very little or no iron depleted into dust grains, i.e., most of or all of the dust grains have been destroyed in the hot ISM.
Intra- to multi-decadal terrestrial precipitation regimes at the end of the 20th century

Intra- to multi-decadal (IMD) variation in terrestrial precipitation during 1901-98 was evaluated here by sampling annual precipitation rankings over 6-30 year moving time windows and converting those rankings to Mann-Whitney U statistics. Those U statistics were then used to identify the most significant concentrations of wet and dry years relative to a null hypothesis that assumes stationary climate variability. This time series analysis approach served as the basis of a climate survey method used to identify IMD precipitation regimes over continental areas, and was also used to evaluate IMD variation in time series of annual precipitation spatially averaged over those areas. These methods showed a highly significant incidence of wet years over North America during 1972-98, with 8 of the 10 wettest years of 1901-98 occurring during that 27-year period. A comparably significant incidence of late century wetness was also found over a northern Europe grid region, with 7 of the 10 wettest years occurring during 1978-98. Although significant wet and dry regimes were also found over other land areas in the last decades of the 20th century, the late century North American and northern European wet periods stood out as the most statistically significant found here during 1901-98. It is suggested that these recent wet periods are actually terrestrial evidence of a single multi-decadal precipitation mode extending across the North Atlantic, and the most observable evidence of an even broader pattern of recent North Atlantic climate change.
Extending electrical resistivity measurements in micro-scratching of silicon to determine thermal conductivity of the metallic phase Si-II

Abstract Ductile Regime Machining (DRM) of semiconductors offers higher quality of the resulting surfaces. To optimize this process, it is necessary to understand the thermal kinetics of silicon metallization under pressure. Such understanding is not yet possible since the metallic phases of silicon aren't readily amenable to thermal characterization through direct measurements. This being the case, one has to rely on processing indirect measurement data to deduce refined estimates of the thermal transport properties of pressurized silicon. A feasible measurement of this sort is the electrical resistivity, since its variation during indentation is often considered an indicator of the formation of the metallic silicon phase Si-II under the indenter. This paper, therefore, describes a procedure by which the average thermal conductivity of the metallic phase of silicon, Si-II, is extracted from electrical resistivity measurements taken in real time. The procedure is based on teaming a temperature evaluation code to the resistivity measurements, thus allowing determination of the conductivity as a function of temperature.
Incorporating biological information into linear models: A Bayesian approach to the selection of pathways and genes

The vast amount of biological knowledge accumulated over the years has allowed researchers to identify various biochemical interactions and define different families of pathways. There is an increased interest in identifying pathways and pathway elements involved in particular biological processes. Drug discovery efforts, for example, are focused on identifying biomarkers as well as pathways related to a disease. We propose a Bayesian model that addresses this question by incorporating information on pathways and gene networks in the analysis of DNA microarray data. Such information is used to define pathway summaries, specify prior distributions, and structure the MCMC moves to fit the model. We illustrate the method with an application to gene expression data with censored survival outcomes. In addition to identifying markers that would have been missed otherwise and improving prediction accuracy, the integration of existing biological knowledge into the analysis provides a better understanding of underlying molecular processes.
Event-by-event fluctuations from decay of a Polyakov loop condensate

Abstract A model for particle production at the deconfining phase transition in QCD is developed, as the semiclassical decay of a condensate for the Polyakov loop. In such a model, generically particle production, as measured on an event-by-event basis, exhibits significant deviations from statistical behavior.
Oxide Addition to a Reactive Polysulfide Flux: Synthesis of K4Ba[Ti6OS20] Containing Isolated [Ti6OS8(S2)6]6− Clusters

The zero-dimensional cluster compound K4 Ba[Ti6 OS8 (S2 )6 ] has been synthesized from a reactive flux similar to that of K2 Sn and Ti used in the synthesis of the one-dimensional compound K4 Ti3 S14 , but augmented by the deliberate introduction of TiO2 . The picture shows the structure of the [Ti6 OS8 (S2 )6 ]6- ion.
Dorsal lateral geniculate substructure in the long-evans rat: a cholera toxin B subunit study.

The pigmented rat is an increasingly important model in visual neuroscience research, yet the lamination of retinal projections in the dLGN has not been examined in sufficient detail. From previous studies it was known that most of the rat dLGN receives monocular input from the contralateral eye, with a small island receiving predominantly ipsilateral projections. Here we revisit the question using cholera toxin B subunit (CTB), a tracer that efficiently fills retinal terminals after intra-ocular injection. We imaged retinal termini throughout the dLGN at 0.5 um resolution and traced areas of ipsilateral and contralateral terminals to obtain a high resolution 3D reconstruction of the projection pattern. Retinal termini in the dLGN are well segregated by eye of origin, as expected. We find, however, that the ipsilateral projections form multiple discrete projection zones in three dimensions, not the single island previously described. It remains to be determined whether these subdomains represent distinct functional sublaminae, as is the case in other mammals.
GRAVITATIONAL MICROLENSING AND THE STRUCTURE OF QUASAR OUTFLOWS

We show that invaluable information on the structure quasar outflows can be obtained by considering microlensing (ML)-induced variability of absorption-line troughs in lensed quasars. Depending on the structure and geometry of the outflowing gas, such extrinsic line variability is manifested as changes to the equivalent width of the trough as well as line profile distortions. Here we consider several physically distinct outflow models having very similar spectral predictions, and show how ML-induced absorption-line variability can be used to distinguish between them. Possible merits from future systematic studies of these effects are exemplified.
Spontaneous spin coherence in n -GaAs produced by ferromagnetic proximity polarization

We find that photoexcited electrons in an n-GaAs epilayer rapidly (50 ps) spin polarize due to the proximity of an epitaxial ferromagnetic metal. Comparison between MnAs/GaAs and Fe/GaAs structures reveals that this coherent spin polarization is aligned antiparallel and parallel to their magnetizations, respectively. In addition, the GaAs nuclear spins are dynamically polarized with a sign determined by the spontaneous electron-spin orientation. In Fe/GaAs, competition between nuclear hyperfine and applied magnetic fields results in complete quenching of electron-spin precession.
Novel Approaches to Solution-Combustion Synthesis of Nanomaterials

Solution-combustion is an attractive approach to synthesis of nanomaterials for a variety of appli- cations, including catalysts, fuel cells, and biotechnology. In this paper, several novel methods based on the combustion of a reactive solution are presented. These methods include self-propagating sol-gel combustion and combustion of impregnated inert and active supports. It was demonstrated that, based on the fundamental understanding of the considered combustion processes, a variety of extremely high surface area materials could be synthesized. The controlling process parameters are defined and discussed. Examples of materials synthe- sized by the above methods are presented. For the first time, a continuous technology for production of nano- powders by using the solution combustion approach is demonstrated.
On Semisimple Hopf Algebras of Dimension 2 m , II

In this paper we classify, up to equivalence, all semisimple nontrivial Hopf algebras of dimension 22n+1 for n ≥ 2 over an algebraically closed field of characteristic 0 with the group of group-like elements isomorphic to $\mathbb {Z}_{2^{n}}\times \mathbb {Z}_{2^{n}}$ . Moreover we classify all such nonisomorphic Hopf algebras of dimension 32 and show that they are not twist-equivalent to each other. More generally, given an abelian group of order 2 m−1 we give an upper bound for the number of nonisomorphic nontrivial Hopf algebras of dimension 2 m which have this group as their group of group-like elements.
Whole-field displacement and strain measurements: application to biomechanics

There are a plethora of interference techniques which can be utilized for whole-field displacement and strain measurements. This paper contains a brief overview of some of the whole-field interference techniques which can be used for measurements in biomechanics. Rather than provide an exhaustive review of the applications of these techniques in biomechanics, however, two specific applications using holographic interferometry (HI) are presented. Although focused on HI, this discussion is pertinent to a range of whole-field interference techniques. The term whole-field is used to differentiate a class of interference techniques which provide information about displacement and strain over a large field of view, from point-by-point methods which require the repetition of the experimental protocol at an ensemble of points to produce similar information. Strain gauge measurements are a prime example of the latter class of techniques. Although whole-field methods often require an analysis at discrete points, the simultaneous acquisition of information at an ensemble of points is characteristic of these techniques.
Discrete Anomaly Matching

We extend the well-known 't Hooft anomaly matching conditions for continuous global symmetries to discrete groups. We state explicitly the matching conditions for all possible anomalies which involve discrete symmetries. There are two types of discrete anomalies. For Type I anomalies, the matching conditions always have to be satisfied regardless of the details of the massive bound state spectrum. The Type II anomalies have to be also matched except if there are fractionally charged massive bound states in the theory. We check discrete anomaly matching in recent solutions of certain N = 1 supersymmetric gauge theories, most of which satisfy these constraints. The excluded examples include the chirally symmetric phase of N = 1 pure symmetric Yang-Mills theories described by the Veneziano-Yankielowicz Lagrangian and certain non-supersymmetric confining theories. The conjectured self-dual theories based in exceptional gauge groups do not satisfy discrete anomaly matching nor mapping of operators, and are viable only if the discrete symmetry in the electric theory appears as an accidental symmetry in the magnetic theory and vice versa.
Chemical-mechanical polishing of oxide thin films: the Rebinder-Westwood phenomenon revisited

The role of hydrogen interactions and diffusion in oxide thin films subjected to chemical-mechanical polishing is assessed through Fourier transform infrared spectroscopy (FTIR). The results are discussed in the context of the efficacy of hydrogen transport on controlling the properties of thin oxide films and structural descriptions of oxide glasses. The implications of these results are for the first time put into the context of the early work of Rebinder and Westwood on chemical induced surface modifications in materials and their effect on wear behavior.
Constrained linear filtering as a multistage process

Abstract Linear filtering in the presence of contraints is viewed as a multistage process. This appeoach gives some new results and leads to a simple building block method for the constrained filter.
Modeling Multiple Risks: Hidden Domain of Attraction

A sub-model of multivariate regular variation called hidden regular variation facilitates more accurate estimation of joint tail probabilities in the presence of asymptotic independence. A related concept called hidden domain of attraction can sometimes offer similar estimation assistance in circumstances where hidden regular variation is absent. Examples and discussion illustrate strengths and limitations of this concept. We outline estimation techniques where applicable.
Bed-parallel compaction bands in aeolian sandstone: Their identification, characterization and implications

Abstract This study combines field observations and laboratory analyses to identify and characterize predominantly bed-parallel compaction bands in the aeolian Aztec Sandstone exposed in the Valley of Fire State Park, Nevada. These bed-parallel compaction bands display morphological and geometrical characteristics of deformation bands of various modes previously described in the literature, such as positive relief, echelon geometry, “bridge” and “eye” structure, and zonal occurrence. Portions of some bands cross-cut sedimentary layers, thereby distinguishing themselves from depositional bedding. Laboratory image analyses of several samples collected from bed-parallel bands, using a computational rock physics algorithm, show that their porosities are less than half that of the host rock and their permeability is nearly one order of magnitude less. In addition, the study area includes compaction bands that have dip angles ranging from sub-horizontal to greater than 20°. Parts of these bands have even higher dip angles and show evidence for increasing intragranular fracturing and shearing as the band inclination increases. We attribute this variation to shear-enhanced compaction, a mechanism proposed earlier by experimental rock mechanists. One of the implications of the occurrence of localized compaction in the form of discrete bands parallel to flat-lying and low-angle bedding is that it provides an alternative or an additional mode to a vertically continuous compaction in loose or poorly cemented sediments. If pervasive, bed-parallel compaction bands with significantly lower porosity than that of the surrounding undeformed rock should result in a significant heterogeneity and vertical anisotropy in seismic velocities and hydraulic properties of granular rocks.
Galois-stability for Tame abstract elementary classes

We introduce tame abstract elementary classes as a generalization of all cases of abstract elementary classes that are known to permit development of stability-like theory. In this paper, we explore stability results in this new context. We assume that is a tame abstract elementary class satisfying the amalgamation property with no maximal model. The main results include:. Theorem 0.1. Suppose that is not only tame, but -tame. If and is Galois stable in μ, then , where is a relative of κ(T) from first order logic. is the Hanf number of the class . It is known that . The theorem generalizes a result from [17]. It is used to prove both the existence of Morley sequences for non-splitting (improving [22, Claim 4.15] and a result from [7]) and the following initial step towards a stability spectrum theorem for tame classes:. Theorem 0.2. If is Galois-stable in some , then is stable in every κ with κμ=κ. For example, under GCH we have that Galois-stable in μ implies that is Galois-stable in μ+n for all n < ω.
An historical look at the debate over how to organize federal government documents in depository libraries

Abstract This report, which describes and evaluates the reactions to the various ways of organizing Federal government documents in U.S. depository libraries, shows that most of the arguments concerning the separate vs. the distributional controversy were formulated during the 1930's and early 1940's. Since that time, there have been few major contributions to this controversy. In addition, a review of the literature shows that the controversy has been based on opinions and assumptions rather than objective evidence. Scientific studies are needed to correct this deficiency.
Linear Fractionally Damped Oscillator

The linearly damped oscillator equation is considered with the damping term generalized to a Caputo fractional derivative. The order of the derivative being considered is 0≤𝑣≤1. At the lower end (𝑣=0) the equation represents an undamped oscillator and at the upper end (𝑣=1) the ordinary linearly damped oscillator equation is recovered. A solution is found analytically, and a comparison with the ordinary linearly damped oscillator is made. It is found that there are nine distinct cases as opposed to the usual three for the ordinary equation (damped, over-damped, and critically damped). For three of these cases it is shown that the frequency of oscillation actually increases with increasing damping order before eventually falling to the limiting value given by the ordinary damped oscillator equation. For the other six cases the behavior is as expected, the frequency of oscillation decreases with increasing order of the derivative (damping term).
Mathematical model of clonal selection and antibody production.

Equations are developed to describe the effects of interaction between antigen and target cell. The model shows promise in predicting the constants of simple experimental systems.
ANISOTROPIC THERMAL CONDUCTION AND THE COOLING FLOW PROBLEM IN GALAXY CLUSTERS

We examine the long-standing cooling flow problem in galaxy clusters with three-dimensional magnetohydrodynamics simulations of isolated clusters including radiative cooling and anisotropic thermal conduction along magnetic field lines. The central regions of the intracluster medium (ICM) can have cooling timescales of {approx}200 Myr or shorter-in order to prevent a cooling catastrophe the ICM must be heated by some mechanism such as active galactic nucleus feedback or thermal conduction from the thermal reservoir at large radii. The cores of galaxy clusters are linearly unstable to the heat-flux-driven buoyancy instability (HBI), which significantly changes the thermodynamics of the cluster core. The HBI is a convective, buoyancy-driven instability that rearranges the magnetic field to be preferentially perpendicular to the temperature gradient. For a wide range of parameters, our simulations demonstrate that in the presence of the HBI, the effective radial thermal conductivity is reduced to {approx}<10% of the full Spitzer conductivity. With this suppression of conductive heating, the cooling catastrophe occurs on a timescale comparable to the central cooling time of the cluster. Thermal conduction alone is thus unlikely to stabilize clusters with low central entropies and short central cooling timescales. High central entropy clusters have sufficiently long cooling times that conduction canmore » help stave off the cooling catastrophe for cosmologically interesting timescales.« less
Detection of N-acetylglycine, N-acetylglycylglycine, and N-acetylglycylglycylglycine by paper chromatography

This paper reports that the developing solvent of Kirchenmayer and Kuffner, n-butanol-acetic acid-water (8:1:10, v/v) can be used to separate and detect N-acetylglycine, N-acetylglycylglycine, and N-acetylglycylglycylglycine. The chromatographic procedure is described. After heating at 100/sup 0/C, the spots could be seen under uv light; acetone-bromocresol green-morpholine can also be used to make the spots show up. The R/sub f/ values are 0.59, 0.43, and 0.33, respectively. This procedure was used to detect these compounds in aqueous solutions of diglycine, triglycine, and tetraglycine, which were used as gamma-radiolysis targets. (DLC)
Uterine pathology in women undergoing minimally invasive hysterectomy using morcellation.

While minimally invasive surgery has improved outcomes for hysterectomy, the procedure requires removal of the uterus through small incisions. Morcellation, or fragmentation of the uterus into smaller pieces, is one method to remove the uterus. Recently, concern has been raised that morcellation may result in the spread of undetected malignancies.1 Despite the commercial availability of electric power morcellators for 2 decades, accurate estimates of the prevalence of malignancy at the time of electric power morcellation (herein referred to as morcellation) are lacking,1,2 with single-center studies reporting prevalences from 9 to 100 in 10,000.3,4, We used a large insurance database to investigate the prevalence of underlying cancer in women who underwent uterine morcellation.
A Comparative Study of Three Sorting Techniques in Performing Cognitive Tasks on a Tabular Representation

This study investigated the impacts of three sorting techniques on various cognitive tasks performed on a tabular representation. The tasks under study were a multiattribute object selection task and selected low-level analytic tasks. Three sorting techniques, including sorting by a column (Typical Sort), sorting by all columns simultaneously (SimulSort), and sorting by all columns with faithful vertical locations (ParallelTable), were compared with a static table without the sorting feature (Baseline). An incentivized controlled laboratory study with 80 participants and a preliminary eye-tracker study were conducted to better understand the strengths and weaknesses of the four different approaches. SimulSort and ParallelTable were found to significantly improve the performance of multiattribute object selection. ParallelTable, however, suffers from an occlusion problem, so it is not an appropriate support for some low-level analytic tasks. The findings were used to propose appropriate sorting techniques ...
On Procesi bundles

Procesi bundles are certain vector bundles on symplectic resolutions of quotient singularities for wreath-products of the symmetric groups with the Kleinian groups. Roughly speaking, we can define Procesi bundles as bundles on resolutions that provide derived McKay equivalence. In this paper we classify Procesi bundles on resolutions obtained by Hamiltonian reduction and relate the Procesi bundles to the tautological bundles on the resolutions. Our proofs are based on deformation arguments and a connection of Procesi bundles with symplectic reflection algebras.
Prophylaxis with antipsychotic medication reduces the risk of post-operative delirium in elderly patients: a meta-analysis.

Background Delirium commonly occurs in hospitalized elderly patients, resulting in increased morbidity and mortality. Although evidence for treatment of delirium exists, evidence supporting pharmacologic prevention of delirium in high risk patients is limited. Objective This review examined whether delirium in at-risk patients can be prevented with antipsychotic prophylaxis in the inpatient setting. Data sources A systematic literature review of articles from January 1950 to April 2012 was conducted in PubMed, PsychInfo, and Cochrane Controlled Trials and databases. Study selection Five studies (1491 participants) met our inclusion criteria for analysis. Medication administered included haloperidol (three studies), risperidone (one study), and olanzapine (1 study). All five studies examined older post-surgical patients, spanning five different countries. Data extraction Only RCTs of antipsychotic medication used to prevent delirium were included. Key words used in the search were: “delirium,” “encephalopathy,” “ICU psychosis,” “prevention,” and “prophylaxis.” Studies had to include a validated method of diagnosing delirium. Data analysis was performed using the Metan command in Stata (Stata Corp LP, College Station, TX). Results The pooled relative risk of the five studies resulted in a 50% reduction in the relative risk of delirium among those receiving antipsychotic medication compared with placebo (RR(95% CI): 0.51 (0.33–0.79; heterogeneity, p Conclusions Although few studies have examined prophylactic use of antipsychotics, this analysis suggests that perioperative use of prophylactic antipsychotics may effectively reduce the overall risk of postoperative delirium in elderly patients.
Eating Self‐Efficacy and Binge Eating Disorder in Obese Women

Investigators have begun to identify characteristics of obese individuals with binge eating disorder (BED) so that treatment programs can be tailored to meet the needs of this population. One important area in behavior change is self-efficacy. However, the relationship between BED and eating self-efficacy has received limited empirical investigation. In this study, obese women with BED had significantly lower eating self-efficacy and higher levels of depression compared with non-BED obese women. Additionally, the relationship between eating self-efficacy and BED was not mediated by level of depression. If further investigations support these findings, programs for BED should incorporate skills to enhance eating self-efficacy and foster strategies to manage negative affect.
Velocities from Cross-Correlation: A Guide for Self-Improvement

The measurement of Doppler velocity shifts in spectra is a ubiquitous theme in astronomy, usually handled by computing the cross-correlation of the signals and finding the location of its maximum. This paper addresses the problem of the determination of wavelength or velocity shifts among multiple spectra of the same, or very similar, objects. We implement the classical cross-correlation method and experiment with several simple models to determine the location of the maximum of the cross-correlation function. We propose a new technique, self-improvement, to refine the derived solutions by requiring that the relative velocity for any given pair of spectra be consistent with all others. By exploiting all available information, spectroscopic surveys involving large numbers of similar objects may improve their precision significantly. As an example, we simulate the analysis of a survey of G-type stars with the SDSS instrumentation. Applying self-improvement refines relative radial velocities by more than 50% at low signal-to-noise ratios. The concept is equally applicable to the problem of combining a series of spectroscopic observations of the same object, each with a different Doppler velocity or instrument-related offset, into a single spectrum with an enhanced signal-to-noise ratio.
Grubbs Cross-Metathesis Pathway for a Scalable Synthesis of γ-Keto-α,β-unsaturated Esters

A direct and scalable route to γ-keto-α,β-unsaturated esters, useful intermediates in medicinal chemistry and natural products synthesis, is reported. The key step involves the use of Grubbs’ second-generation olefin metathesis catalyst for cross-metathesis of alkyl acrylates and 2° allylic alcohols. The metathesis step is followed by oxidation to give the desired products in high yield on scales of up to 25 g.
Power-switched sample-and-hold provides accurate analog inputs for ADC in low-power system

This paper describes the design of a low-power, two-channel, 12-bit, data acquisition system with a conversion rate of 240 samples per second on each of the two input channels. Power switching the sample-and-hold module resulted in a power reduction of 140 mW compared with a continuously powered system. The total power consumption for the system was 102 mW. Preliminary information is given about the warm-up characteristics of a variety of operational amplifiers and a commercial sample-and-hold module; this is not available in the standard data books.
Bayesian inference for periodic regime-switching models

We present a general class of nonlinear time-series Markov regime-switching models for seasonal data which may exhibit periodic features in the hidden Markov process as well as in the laws of motion in each of the regimes. This class of models allows for non-trivial dependencies between seasonal, cyclical and long-term patterns in the data. To overcome the computational burden we adopt a Bayesian approach to estimation and inference. This paper contains two empirical examples as illustration, one uses housing starts data while the other employs US post-Second World War industrial production. © 1998 John Wiley & Sons, Ltd.
Cumulative Attestation Kernels for Embedded Systems

To mitigate the threat of malware intrusions on networked embedded systems, it is desirable to provide remote attestation assurances for them. Embedded systems have special limitations concerning cost, power efficiency, computation, and memory that influence how this goal can be achieved. Moreover, many types of applications require integrity guarantees for the system over an interval of time rather than just at a given instant. We propose a Cumulative Attestation Kernel (CAK) that addresses these concerns. We demonstrate the value of CAKs for Advanced Metering Infrastructure (AMI) and show how to implement a CAK in less than one quarter of the memory available on low end flash MCUs similar to those used in AMI deployments. Regarding this prototype, we present the first formal proof we are aware of that a system is tolerant to power supply interruptions. We also discuss how to provide cumulative attestation for devices with tighter memory constraints by offloading computation and storage onto a Cumulative Attestation Coprocessor (CAC).
Effect of tool wear on rolling contact fatigue performance of superfinish hard machined surfaces

This study investigates the effect of tool wear on the rolling contact fatigue performance of superfinish hard machined surfaces. The rolling contact fatigue test results indicate that the flank wear width can contribute to the prediction accuracy of fatigue life model for the CBN tool with a tool nose radius of 0.79 mm. If the relationship between tool wear and the residual stress distribution and the relationship between tool wear and the micro-hardness distribution are established, it is expected that tool wear can contribute to the prediction accuracy of fatigue life model for more general conditions.
THE DQ HERCULIS STARS

We review the properties of the DQ Herculis stars: cataclysmic variables containing an accreting, magnetic, rapidly rotating white dwarf. These stars are characterized by strong X-ray emission, high-excitation spectra, and very stable optical and X-ray pulsations in their light curves. There is considerable resemblance to their more famous cousins, the AM Herculis stars, but the latter class is additionally characterized by spin-orbit synchronism and the presence of strong circular polarization. We list eighteen stars passing muster as certain or very likely DQ Her stars. The rotational periods range from 33 s to 2.0 hr. Additional periods can result when the rotating searchlight illuminates other structures in the binary. A single hypothesis explains most of the observed properties: magnetically channeled accretion within a truncated disk. Some accretion flow still seems to proceed directly to the magnetosphere, however. The white dwarfs' magnetic moments are in the range 10(sup 32) - 10(sup 34) G cc, slightly weaker than in AM Her stars but with some probable overlap. The more important reason why DQ Hers have broken synchronism is probably their greater accretion rate and orbital separation. The observed L(sub x)/L(sub V) values are surprisingly low for a radially accreting white dwarf, suggesting that most of the accretion energy is not radiated in a strong shock above the magnetic pole. The fluxes can be more satisfactorily explained if most of the radial infall energy manages to bypass the shock and deposit itse lf directly in the white dwarf photosphere, where it should emerge as extreme ultraviolet (EUV) radiation. This also provides an adequate source of ionizing photons to power the high-excitation optical and UV emission lines. This is probably the DQ Her analog to the famous 'soft X-ray excess' in AM Her stars. However, unlike the AM Her case, this radiation has not been directly observed, so the analogy must not (yet) be embraced too firmly. There is some conventional wisdom today which segregates the short-period from the long-period DQ Her stars. But the observational grounds for this distinction are slim, except in one respect: X-ray emission from short-period systems appears to be weaker and softer. This must be due to the shallower depth of the potential well, and/or the greater difficulty the fast rotators have in enforcing radial accretion flow.
Ambiguous Allure: The Value–Pragmatics Model of Ethical Decision Making

Research in organizational ethics emphasizes those dispositional factors that are expected to foster positive ethical behavior. We seek to contribute to this literature by including personal values that are in contention with moral outcomes. Specifically, we combine the values of hedonism and power with benevolence and universalism. Our underlying premise of this value–pragmatics model is that nonmoral, as well as moral, dispositional characteristics simultaneously influence ethical decision making. We further contribute to the existing research by investigating how these contending values interact with situational factors, such as performance rewards and punishments for unethical conduct. We administer an experiment to subjects (N = 177) and analyze their decisions regarding the likelihood they would act unethically. Results indicate that both morally relevant and nonmoral variables have direct effects on these decisions, and that nonmoral as well as moral values interact with situational factors to significantly influence decisions. Implications for practice and research are discussed.
MODELING OF PULSATING PERIPHERAL BIOHEAT TRANSFER USING FRACTIONAL CALCULUS AND CONSTRUCTAL THEORY

Fractional calculus provides novel mathematical tools for modeling physical and biological processes. The bioheat equation is often used as a first order model of heat transfer in biological systems. In this paper we describe the formulation of the bioheat transfer in one dimension in terms of the fractional order differentiation with respect to time. The solution to the resulting fractional order partial differential equation reflects the interaction of the system with the dynamics of its response to the pulsed surface or volume heating and cooling. The resulting expression for the heat flux in terms of the fractional order is used to derive an expression for the depth of thermal penetration. This depth of thermal penetration, expressed as a function of time, is optimized using constructal theory, which in turn leads to the determination of the optimal time of pulsating (on‐off) heating and cooling. The advantage of using the fractional heat flux expression is demonstrated by comparing the results with that of optimization of the integer heat flux expression, which yields an ideal unrealistic condition of equal time periods for optimal cooling and heating. An example from cryogenic spray cooling of a peripheral tissue region during laser surgery is used to illustrate the utility of combining the methods of fractional calculus and constructal theory. This combined approach is useful to develop an approximate solution to complex biomedical problems that involve pulsating behavior and rhythmicity.
Free-field correction factor for spherical acoustic waves impinging on cylinders

The scattering and diffraction of spherical waves by an infinite rigid cylinder is analytically studied for monopole and dipole acoustic sources. A correction factor at the cylinder surface for the change in the free-field radiation levels due to the presence of the cylinder is calculated. The results indicate that the correction factor is sensitive to source frequency and location. Regions of negative correction factor, due to shadowing and creeping wave behavior are identified.
Treatment of intracranial metastatic esthesioneuroblastoma

BACKGROUND Esthesioneuroblastoma (ENB) is an uncommon tumor that may metastasize to the central nervous system (CNS). To the authors' knowledge there is no current consensus regarding treatment. The current study was conducted to determine the toxicity and response rate of combined modality therapy in the treatment of patients with ENB metastatic to the brain. METHODS Six patients (2 men and 4 women) ranging in age from 47–61 years (median age, 53.5 years) with ENB had clinical and neuroradiographic evidence of CNS metastases (brain parenchyma in 6 patients and leptomeningeal metastases in 3 patients). CNS-directed therapy included radiotherapy (to the brain in three patients and to the spine in two patients) and chemotherapy (systemic in six patients and regional in three patients). Systemic chemotherapy was comprised of carboplatin, lomustine, and vincristine administered every 2 months. Patients were evaluated by neuroradiographic and neurologic examination every other month. RESULTS Between 1–6 cycles of systemic chemotherapy were administered (median, 4.5 cycles). and 6–19 cycles of regional chemotherapy were administered (median, 17 cycles). Toxicity included aseptic meningitis (three patients), radiation enteritis (one patient), and ≥ Grade 3 (according to the National Cancer Institute Common toxicity Criteria) myelosuppression (four patients). Two patients required hospitalization for neutropenic fever and two patients required a transfusion (platelets in two patients and red blood cells in one patient). No treatment-related deaths were reported. A partial response was achieved in four patients, and two patients demonstrated progressive disease. The median duration of response was 9 months (range, 2–12 months). Overall survival ranged from 3–13 months (median, 10.5 months). The cause of death was progressive parenchymal brain disease in three patients, systemic disease in two patients, and leptomeningeal disease in one patient. CONCLUSIONS In the small cohort of patients in the current study, combined modality therapy was found to have modest toxicity and palliative efficacy. Cancer 2002;95:243–48. © 2002 American Cancer Society. DOI 10.1002/cncr.10679
Iridium-catalyzed, asymmetric amination of allylic alcohols activated by Lewis acids.

The direct, Ir-catalyzed, regio- and enantioselective amination of allylic alcohols with Lewis acid activators to form branched allylic amine products is reported. The reactions of arylamines, benzylic amines, and secondary aliphatic amines in the presence of Nb(OEt)5 as activator occurred with high regioselectivities and high enantioselectivities. These results led to the development of Ir-catalyzed reactions of allylic alcohol with arylamines and BPh3 as activator in catalytic amounts. These reactions are rare examples of enantioselective substitutions of allylic alcohols. They are particularly unusual examples of the substitution of allylic alcohols to generate branched substitution products from monosubstituted allylic alcohols and of enantioselective substitutions of allylic alcohols with amine nucleophiles.
A New Technique for Text Data Compression

This paper presents how ternary representation of numbers can be utilized to compress text data with fixed-symbol-length coding techniques. We use a binary map for ternary digits and introduce a method to use the binary 11-pair, which has never been use for coding data before, and we further use 4-Digits ternary representation of alphabet with lowercase and uppercase letters. We find a way to minimize the length of the bits string, which is only possible in ternary representation thus efficiently reducing the length of the code. We also find some connection between this technique of coding data and Fibonacci numbers.
Do international shocks affect small wholesalers and retailers

Previous research has suggested that the smallest firms are those most vulnerable to international competition, as measured by exchange rate fluctuations and import shares. However, that work—and the overwhelming bulk of the empirical literature on determinants of exit or firm survival—dealt entirely with the manufacturing sector of the economy. This paper analyzes annual US data for 1989–2005 for about 50 wholesale and retail sectors to explain small firm exit rates in several employment size categories. The main result is that wholesalers respond negatively to a stronger currency in a manner similar to that of manufacturers, while retailers are generally unaffected.
Reduction of alcohol drinking of alcohol-preferring (P) and high-alcohol drinking (HAD1) rats by targeting phosphodiesterase-4 (PDE4)

Rationale Phosphodiesterase-4 (PDE4) and neuroimmune signaling have been posited to regulate alcohol drinking.
The refined process structure tree

We consider a workflow graph as a model for the control flow of a business process and study the problem of workflow graph parsing, i.e., finding the structure of a workflow graph. More precisely, we want to find a decomposition of a workflow graph into a hierarchy of sub-workflows that are subgraphs with a single entry and a single exit of control. Such a decomposition is the crucial step, for example, to translate a process modeled in a graph-based language such as BPMN into a process modeled in a block-based language such as BPEL. For this and other applications, it is desirable that the decomposition be unique, modular and as fine as possible, where modular means that a local change of the workflow graph can only cause a local change of the decomposition. In this paper, we provide a decomposition that is unique, modular and finer than in previous work. We call it the refined process structure tree. It is based on and extends similar work for sequential programs by Tarjan and Valdes [ACM POPL '80, 1980, pp. 95-105]. We give two independent characterizations of the refined process structure tree which we prove to be equivalent: (1) a simple descriptive characterization that justifies our particular choice of the decomposition and (2) a constructive characterization that allows us to compute the decomposition in linear time. The latter is based on the tree of triconnected components (elsewhere also known as the SPQR tree) of a biconnected graph.
Conferring Thermostability to Mesophilic Proteins through Optimized Electrostatic Surfaces

Recently, there have been several experimental reports of proteins displaying appreciable stability gains through mutation of one or two amino acid residues. Here, we employ a simple theoretical model to quickly screen mutant structures for increased thermostability through optimization of the protein's electrostatic surface. Our results are able to reproduce the experimental observation that elimination of like-charge repulsions and creation of opposite-charge attractions on the protein surface is an efficient method to confer thermostability to a mesophilic protein. Using Poisson-Boltzmann electrostatics, we calculate relative protein stabilities for the exhaustive surface mutagenesis of the cold shock, RNase T1, and CheY proteins. Comparison with 25 experimentally characterized cold shock protein mutants reveals an average correlation of 0.86. The model is also quantitatively accurate when reproducing the experimental D49A and D49H mutant stabilities of RNase T1. This work represents the first comprehensive in silico screening of mutant candidates likely to confer thermostability to mesophilic proteins through optimization of surface electrostatics. Systematic single mutant, followed by double mutant, screening yields a limited number of mutant structures displaying significant stability gains suitable for subsequent experimental characterization.