cssi/SciSciGPT-SciSciNet huggingface dataset:
Hot Corrosion in a Temperature Gradient

Hot corrosion is the accelerated attack of materials at elevated temperatures that is induced by a thin film of fused salt. Many materials that experience hot corrosion are exposed to high heat fluxes and temperature gradients. The hot corrosion of metals can be described by the dissolution of a protective metal oxide into the fused salt and the subsequent precipitation of the metal oxide in a non-protective form. Rapp and Goto have established a criterion for the sustained hot corrosion of a pure metal that the solubility gradient of the protective oxide in the salt film must be negative at the oxide/ salt interface. The influence of a temperature gradient on the metal oxide solubility gradient (and the predicted hot corrosion susceptibility) is discussed. Solubility data for NiO in Na 2 SO 4 are used to illustrate the effects of a temperature gradient. The effects of a temperature gradient were determined by examining various combinations of dissolution reactions, oxidants, and transport kinetics. Based on these results, and the thinness of the molten salt films, temperature gradients are not expected to be of importance to hot corrosion fluxing mechanisms.
Experimental investigation of line-tying effects on the spheromak tilt mode

Abstract In the absence of close fitting walls or conducting elements, the spheromak plasma configuration is unstable to at least one global MHD mode (tilting or shifting). Previous theoretical work suggested that line-tying effects could play a role in slowing down these modes. Line-tying was investigated in the Proto S-1/C spheromak device by a direct measurement of the line-tying character of the perturbed current within a passive stabilizer. The ring model of tilting is extended to include line-tying stabilization by taking into account the plasma sheath resistance. Comparison with experimental results show good agreement between predicted and observed growth rates.
Dusty waves on a starry sea : The mid-infrared view of M31

Mid-infrared observations of the Andromeda galaxy, M31, obtained with the Infrared Array Camera on board the Spitzer Space Telescope are presented. The image mosaics cover areas of approximately 37 × 16 and include the satellite galaxies M32 and NGC 205. The appearance of M31 varies dramatically in the different mid-infrared bands, from the smooth bulge and disk of the old stellar population seen at 3.6 μm to the well-known "10 kpc ring" dominating the 8 μm image. The similarity of the 3.6 μm and optical isophotes and the nearly constant optical-mid-infrared color over the inner 400'' confirm that there is no significant extinction at optical wavelengths in M31's bulge. The nuclear colors indicate the presence of dust but not an infrared-bright active galactic nucleus. The integrated 8 μm nonstellar luminosity implies a star formation rate of 0.4 M☉ yr-1, consistent with other indicators that show M31 to be a quiescent galaxy.
Gravitational Wave Astrophysics: Opening the New Frontier

The gravitational wave window onto the universe is expected to open in ∼5 years, when ground‐based detectors make the first detections in the high‐frequency regime. Gravitational waves are ripples in spacetime produced by the motions of massive objects such as black holes and neutron stars. Since the universe is nearly transparent to gravitational waves, these signals carry direct information about their sources—such as masses, spins, luminosity distances, and orbital parameters—through dense, obscured regions across cosmic time. This article explores gravitational waves as cosmic messengers, highlighting key sources, detection methods, and the astrophysical payoffs across the gravitational wave spectrum.
Region-based video coding using backward motion-field segmentation

We introduce a novel region-based video compression framework based on morphology to efficiently capture motion correspondences between consecutive frames in an image sequence. Our coder is built on the observation that the motion field associated with typical image sequences can be segmented into component motion subfield 'clusters' associated with distinct objects or regions in the scene, and further that these clusters can be efficiently captured using morphological operators in a 'backward' framework that avoids the need to send region shape information. Regions segmentation is performed directly on the motion field by introducing a small 'core' for each cluster that captures the essential features of the cluster and reliably represents its motion behavior. Cluster matching is used in lieu of the conventional block matching methods of standard video codecs to define a cluster motion representation paradigm. Furthermore, a region-based pel-recursive approach is applied to find the refinement motion field for each cluster and the cluster motion prediction error image is coded by a novel adaptive scalar quantization method. Experimental results reveal a 10-20 percent reduction in prediction error energy and 0.5-2 dB gain in final reconstructed PSNR over the standard MPEG-12 coder at typical bitrates of 500 kbits/sec to 1 Mb/sec on standard test sequences.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Optimal robust smoothing extragradient algorithms for stochastic variational inequality problems

We consider stochastic variational inequality problems where the mapping is monotone over a compact convex set. We present two robust variants of stochastic extragradient algorithms for solving such problems. Of these, the first scheme employs an iterative averaging technique where we consider a generalized choice for the weights in the averaged sequence. Our first contribution is to show that using an appropriate choice for these weights, a suitably defined gap function attains the optimal rate of convergence of O(1 over √k). In the second part of the paper, under an additional assumption of weak-sharpness, we update the stepsize sequence using a recursive rule that leverages problem parameters. The second contribution lies in showing that employing such a sequence, the extragradient algorithm possesses almost-sure convergence to the solution as well as convergence in a mean-squared sense to the solution of the problem at the rate O(1 over k). Motivated by the absence of a Lipschitzian parameter, in both schemes we utilize a locally randomized smoothing scheme. Importantly, by approximating a smooth mapping, this scheme enables us to estimate the Lipschitzian parameter. The smoothing parameter is updated per iteration and we show convergence to the solution of the original problem in both algorithms.
Superconductivity and chiral symmetry breaking with fermion clusters

Abstract Cluster variables have recently revolutionized numerical work in certain models involving fermionic variables. This novel representation of fermionic partition functions is continuing to find new applications. After describing results from a study of a two dimensional Hubbard type model that confirm a superconducting transition in the Kosterlitz-Thouless universality class, we show how a cluster type algorithm can be devised to study the chiral limit of strongly coupled lattice gauge theories with staggered fermions.
Response of thin films and substrate to micro-scale laser shock peening

Micro-scale laser shock peening ({mu}LSP) can potentially be applied to metallic structures in microdevices to improve fatigue and reliability performance. Copper thin films on a single-crystal silicon substrate are treated by using {mu}LSP and characterized using techniques of X-ray microdiffraction and electron backscatter diffraction (EBSD). Strain field, dislocation density, and microstructure changes including crystallographic texture, grain size and subgrain structure are determined and analyzed. Further, shock peened single crystal silicon was experimentally characterized to better understand its effects on thin films response to {mu}LSP. The experimental result is favorably compared with finite element method simulation based on single-crystal plasticity.
On a conjecture of Givental

These brief notes record our puzzles and findings surrounding Givental’s recent conjecture which expresses higher genus Gromov–Witten invariants in terms of the genus-0 data. We limit our considerations to the case of a complex projective line, whose Gromov–Witten invariants are well-known and easy to compute. We make some simple checks supporting his conjecture.
Option Pricing Bounds: Synthesis And Extension

The main option pricing bounds in the literature were originally obtained through various disparate methods. I show that those bounds can be derived from a single analytical framework. The key to this synthesis lies in the use of a general expression for the price of a call option depending on the corresponding put option's discount factor. Although the put's discount factor is unknown, it can be bounded from below. I use this lower bound on the put's discount factor to derive traditional lower bounds for call prices. In addition, I extend the literature by finding a new tighter lower bound.
Acyl CoA:cholesterol acyltransferase (ACAT) inhibitors: ureas bearing two heterocyclic head groups

Abstract A series of compounds bearing two heterocyclic substituents were prepared, and evaluated for inhibition of acyl-CoA:cholesterol acyltransferase (ACAT). The heterocyclic groups were chosen for dual potency against hepatic and macrophage cell ACAT. Several examples of ACAT-balanced compounds were discovered, and the results of this study, including synthesis, are presented.
Quantum Riemann Surfaces in Chern-Simons Theory

We construct from first principles the operators $\hat A_M$ that annihilate the partition functions (or wavefunctions) of three-dimensional Chern-Simons theory with gauge groups $SU(2)$, $SL(2,\mathbb{R})$, or $SL(2,\mathbb{C})$ on knot complements $M$. The operator $\hat A_M$ is a quantization of a knot complement's classical $A$-polynomial $A_M(\ell,m)$. The construction proceeds by decomposing three-manifolds into ideal tetrahedra, and invoking a new, more global understanding of gluing in topological quantum field theory to put them back together. We advocate in particular that, properly interpreted, "gluing $=$ symplectic reduction." We also arrive at a new finite-dimensional state integral model for computing the analytically continued "holomorphic blocks" that compose any physical Chern-Simons partition function.
Permutations Restricted by Two Distinct Patterns of Length Three

Define S"n(R;T) to be the set of permutations on n letters which avoid all patterns in the set R and contain each pattern in the multiset T exactly once. In this paper we enumerate S"n(@a;@b) and S"n(@A;{@a,@b}) for all @a @[email protected]?S"3.
PROTOGALACTIC DISK MODELS OF DAMPED Lya KINEMATICS

We present new observational results on the kinematics of the damped Lyα systems. Our full sample now comprises 31 low-ion profiles and exhibits characteristics similar to those of the sample from our previous paper.The primary exception is that the new distribution of velocity widths includes values out to a maximum of nearly 300 km s-1, ≈ 100 km s-1 greater than the previous maximum. These high velocity width systems will significantly leverage models introduced to explain the damped Lyα systems. Comparing the characteristics from low-redshift and high-redshift subsamples, we find no evidence for significant evolution in the kinematic properties of protogalaxies from z = 2.0 to z = 3.3. The new observations give greater statistical significance to the main conclusions of our first paper. In particular, those models inconsistent with the damped Lyα observations in the first paper are ruled out at even higher levels of confidence. At the same time, the observations are consistent with a population of rapidly rotating thick disks (the TRD model) at high redshift, as predicted by cosmologies with early structure formation. Buoyed by the success of the TRD model, we investigate it more closely by considering more realistic disk properties. Our goal is to demonstrate the statistical power of the damped Lyα observations by investigating the robustness of the TRD model. In particular, we study the effects of warping, realistic rotation curves, and photoionization on the kinematics of disks in the TRD model. The principal results are the following: (1) Disk warping has only a minimal effect on the kinematic results, primarily influencing the effective disk thickness. (2) The TRD model is robust to more realistic rotation curves; we point out, however, that the rotation curve derived from centrifugal equilibrium with H I gas alone does not yield acceptable results but that rather flat rotation curves such as those generated by dark matter halos are required. (3) The effects of photoionization require thicker disks to give consistent velocity width distributions.
Investigation of 1,4-elimination reactions of γ-trimethylsilyl alcohols via ionic and radical processes

Abstract Oxidative fragmentation of γ-trimethylsilyl alcohols with cerium ammonium nitrate occurs rapidly via a radical process to provide keto olefins. Attempts to obtain the same products via an ionic-type 1,4-elimination with the trimethylsilyl group as the directing moiety proved unsuccessful, even under a variety of harsh experimental conditions. Instead, dehydration products were produced in certain cases.
Nuclear ground state masses and deformations

Abstract We tabulate the atomic mass excesses and nuclear ground-state deformations of 8979 nuclei ranging from 16O to A = 339. The calculations are based on the finite-range droplet macroscopic model and the folded-Yukawa single-particle microscopic model. Relative to our 1981 mass table the current results are obtained with an improved macroscopic model, an improved pairing model with a new form for the effective-interaction pairing gap, and minimization of the ground-state energy with respect to additional shape degrees of freedom. The values of only nine constants are determined directly from a least-squares adjustment to the ground-state masses of 1654 nuclei ranging from 16O to 263106 and to 28 fission-barrier heights. The error of the mass model is 0.669 MeV for the entire region of nuclei considered, but is only 0.448 MeV for the region N ≥ 65.
Bureaucracy and Public Employee Behavior: A Case of Local Government

Government reinvention advocates assert that less bureaucratic work environments will spark higher creativity, more risk taking, and greater productivity in public employees. Although government reinvention remains a topic of interest to scholars and practitioners alike, these particular arguments lack empirical support. In response, this article tests the relationship between different forms of bureaucratic control (formalization, red tape, and centralization) and reported employee perceptions and behavior in local governments. Analyzing mail survey data from a study of the employees of four cities in a Midwestern state, this article finds that employee responses to bureaucratic control are not as straightforward as reinventionists expect. Different types of bureaucratic control are related to distinct employee responses, and sometimes these responses are the very behaviors that reinventionists seek to trigger by reducing bureaucracy.
Hedging and Liquidity

This article develops a model for evaluating alternative hedging strategies for financially constrained firms. A key advantage of the model is the ability to capture the intertemporal effects of hedging on the firm’s financial situation. We characterize the optimal hedge. A wide range of alternative hedging strategies can be specified and the model allows us to determine in each case if the hedging strategy raises or lowers firm value and by how much. We show that hedging firm value, hedging cash flow from operations and hedging sales revenue are not optimal. The article highlights the fact that every hedging strategy comes packaged with a borrowing strategy which requires careful consideration. Futures markets often provide the most liquid and convenient instruments for managing risk. However, because futures contracts are marked to market, it is often impossible to simultaneously hedge cash flows and values. For example, a futures contract that locked in the value of gold that a corporation planned to extract in one year would generate an uncertain cash flow pattern over the year. This article examines how liquidity and cash flow timing problems associated with different hedging strategies can affect a firm’s value. In our model, the objective for hedging is to increase the firm’s financial flexibility. An optimal hedge maximizes the firm’s liquidityslack in the form of excess cash or unused debt capacitywhen liquidity is most valuable. This lowers the danger of costly financial distress, reduces the effective cost of external financial constraints, and makes value maximizing investments affordable. A firm with no financial constraints does not gain from hedging, and the higher the firm’s financial constraints the greater the potential value of hedging. The value of hedging depends critically on the design of the hedging strategy. We show that the optimal hedge minimizes the variability in the marginal value of the firm’s cash balances. Such a hedge efficiently redistributes cash balances across different states and periods, taking cash from those states for which the marginal cost of the financial constraint is low and giving cash to those states for which the marginal
Foundations of High Impact Entrepreneurship

This survey reviews the theoretical literature on high impact entrepreneurship. The survey is guided in part by the recent classification changes at the Journal of Economic Literature (JEL) regarding entrepreneurship. The board voted to create a new classification code, L26, for entrepreneurship. The JEL intends to use this code for all articles and books that focus on economic questions related to entrepreneurial activity. Publications related to questions on occupational choice issues will be cross classified with J23; those focusing on innovation and entrepreneurship will be cross classified with O31; those focusing on finance will be cross classified with G24 Investment Banking, venture capital, brokerage and rating agencies; those focusing on new firms, start ups; and business related publications on how to be an entrepreneur will be cross classified (or solely classified) with M13. What does this economic literature tell us about entrepreneurship? In order to answer the questions this review covers the intersection of entrepreneurship with labor markets, innovation, and capital markets -- the three pillars of high impact entrepreneurship
Coercive or Corrosive: The Negative Impact of Economic Sanctions on Democracy

This article seeks to analyze the impact that sanctions have on democracy. We argue that economic sanctions worsen the level of democracy because the economic hardship caused by sanctions can be used as a strategic tool by the targeted regime to consolidate authoritarian rule and weaken the opposition. Furthermore, we argue that economic sanctions create new incentives for the political leadership to restrict political liberties, to undermine the challenge of sanctions as an external threat to their authority. Using time-series cross-national data (1972–2000), the findings show that both the immediate and longer‐term effects of economic sanctions significantly reduce the level of democratic freedoms in the target. The findings also demonstrate that comprehensive economic sanctions have greater negative impact than limited sanctions. These findings suggest that sanctions can create negative externalities by reducing the political rights and civil liberties in the targeted state.
Anomalous violation of conservation laws in Minkowski space: spontaneously broken gauge theories

Abstract We extend our previous results on the evolution of quantum Fermi fields in Minkowski gauge field backgrounds to the case of spontaneously broken gauge theories. We obtain a selection rule which relates the amount of fermion number violation to the change in Higgs winding number of the configuration. This selection rule is applicable to any classical solution which dissipates at both early and late times.
Real-time control of geometry and stiffness in adaptive structures

The basic theory is presented for the geometry, stiffness, and damping control of adaptive structures, with emphasis on adaptive truss structures. Necessary and sufficient conditions are given for stress-free geometry control in statically determinate and indeterminate adaptive discrete structures. Two criteria for selecting the controls are proposed, and their use in real-time control is illustrated by numerical simulation results. It is shown that the stiffness and damping control of adaptive truss structures for vibration suppression is possible by elongation and elongation rate dependent feedback forces from the active elements.
Order statistics on optically interconnected multiprocessor systems

Abstract Processor arrays with an optical bus are introduced for parallel computation in this paper. We use the order statistics problem as an example to demonstrate how to design efficient parallel algorithms on such systems. Besides proposing a new algorithm on the model, some basic data movement operations involved in the algorithm are discussed. We believe that these operations can be used to design other parallel algorithms on the same model. Time analysis indicates that order statistics can be done more efficiently on a linear array with a pipelined optical bus than with an electronic bus. The initial results are promising, and the author believes that optical buses may emerge as a powerful communication mechanism for connecting large parallel computer systems in the near future.
Equivalence of arterial and venous blood for [11C]CO2-metabolite analysis following intravenous administration of 1-[11C]acetate and 1-[11C]palmitate

Purpose Sampling of arterial blood for metabolite correction is often required to define a true radiotracer input function in quantitative modeling of PET data. However, arterial puncture for blood sampling is often undesirable. To establish whether venous blood could substitute for arterial blood in metabolite analysis for quantitative PET studies with 1-[11C]acetate and 1-[11C]palmitate, we compared the results of [11C]CO2-metabolite analyses performed on simultaneously collected arterial and venous blood samples.
The generalized shrinkage estimator for the analysis of functional connectivity of brain signals

We develop a new statistical method for estimating functional connectivity between neurophysiological signals represented by a multivariate time series. We use partial coherence as the measure of functional connectivity. Partial coherence identifies the frequency bands that drive the direct linear association between any pair of channels. To estimate partial coherence, one would first need an estimate of the spectral density matrix of the multivariate time series. Parametric estimators of the spectral density matrix provide good frequency resolution but could be sensitive when the parametric model is misspecified. Smoothing-based nonparametric estimators are robust to model misspecification and are consistent but may have poor frequency resolution. In this work, we develop the generalized shrinkage estimator, which is a weighted average of a parametric estimator and a nonparametric estimator. The optimal weights are frequency-specific and derived under the quadratic risk criterion so that the estimator, either the parametric estimator or the nonparametric estimator, that performs better at a particular frequency receives heavier weight. We validate the proposed estimator in a simulation study and apply it on electroencephalogram recordings from a visual-motor experiment.
Fuzzy interaction regression for short term load forecasting

Electric load forecasting is a fundamental business process and well-established analytical problem in the utility industry. Due to various characteristics of electricity demand series and the business needs, electric load forecasting is a classical textbook example and popular application field in the forecasting community. During the past 30 plus years, many statistical and artificial intelligence techniques have been applied to short term load forecasting (STLF) with varying degrees of success. Although fuzzy regression has been tried for STLF for about a decade, most research work is still focused at the theoretical level, leaving little value for practical applications. A primary reason is that inadequate attention has been paid to the improvement of the underlying linear model. This application-oriented paper proposes a fuzzy interaction regression approach to STLF. Through comparisons to three models (two fuzzy regression models and one multiple linear regression model) without interaction effects, the proposed approach shows superior performance over its counterparts. This paper also offers critical comments to a notable but questionable paper in this field. Finally, tips for practicing forecasting using fuzzy regression are discussed.
Rate Acceleration and Long-branch Attraction in a Conserved Gene of Cryptic Daphniid (Crustacea) Species

The nuclear large subunit (LSU) rRNA gene is a rich source of phylogenetic characters because of its large size, mosaic of slowly and rapidly evolving regions, and complex secondary structure variation. Nevertheless, many studies have indicated that inconsistency, bias, and gene-specific error (e.g., within-individual gene family variation, cryptic sequence simplicity, and sequence coevolution) can complicate animal phylogenies based on LSU rDNA sequences. However, most of these studies sampled small gene fragments from expansion segments--among animals only five nonchordate complete LSU sequences are published. In this study, we sequenced near-complete nuclear LSU genes from 11 representative daphniids (Crustacea). The daphniid expansion segment V6 was larger and showed more length variation (90-351 bp) than is found in all other reported LSU V6 sequences. Daphniid LSU (without the V6 region) phylogenies generally agreed with the existing phylogenies based on morphology and mtDNA sequences. Nevertheless, a major disagreement between the LSU and the expected trees involved a positively misleading association between the two taxa with the longest branches, Daphnia laevis and D. occidentalis. Both maximum parsimony (MP) and maximum likelihood (ML) optimality criteria recovered this association, but parametric simulations indicated that MP was markedly more sensitive to this bias than ML. Examination of data partitions indicated that the inconsistency was caused by increased nucleotide substitution rates in the branches leading to D. laevis and D. occidentalis rather than among-taxon differences in base composition or distribution of sites that are free to vary. These results suggest that lineage-specific rate acceleration can lead to long-branch attraction even in the conserved genes of animal species that are almost morphologically indistinguishable.
D-branes and strings as non-commutative solitons

The non-commutative geometry of a large auxiliary B-field simplifies the construction of D-branes as solitons in open string field theory. Similarly, fundamental strings are constructed as localized flux tubes in the string field theory. Tensions are determined exactly using general properties of non-BPS branes, and the non-abelian structure of gauge fields on coincident D-branes is recovered.
A special case of Hadwiger's conjecture

We investigate Hadwiger's conjecture for graphs with no stable set of size 3. Such a graph on at least 2t-1 vertices is not t-1 colorable, so is conjectured to have a K"t minor. There is a strengthening of Hadwiger's conjecture in this case, which states that there is a K"t minor in which the preimage of each vertex of K"t is a single vertex or an edge. We prove this strengthened version for graphs with an even number of vertices and fractional clique covering number less than 3. We investigate several possible generalizations and obtain counterexamples for some and improved results from others. We also show that for sufficiently large n, a graph on n vertices with no stable set of size 3 has a K"1"9"n"^"4"^"/"^"5 minor using only vertices and single edges as preimages of vertices.
Evidence of translations and rotations of gold crystallites vacuum deposited on (111) MgO surfaces at room temperature

Abstract The mobility behaviour at room temperature of small crystallites of gold on freshly electron-beam-cleaved (111) MgO surfaces has been studied. The experi ments were carried out in-situ in a transmission electron microscope under ultra high vacuum conditions. Both translational and rotational movements of crystallites were observed. The experiments lead to the conclusion that non-epitaxy is a necessary condition for particle mobility at low temperatures.
The origin of geomagnetic jerks

Geomagnetic jerks, which in the second half of the twentieth century occurred in 1969 (refs 1, 2), 1978 (refs 3, 4), 1991 (ref. 5) and 1999 (ref. 6), are abrupt changes in the second time-derivative (secular acceleration) of the Earth's magnetic field. Jerks separate periods of almost steady secular acceleration, so that the first time-derivative (secular variation) appears as a series of straight-line segments separated by geomagnetic jerks. The fact that they represent a reorganization of the secular variation implies that they are of internal origin (as has been established through spherical harmonic analysis7), and their short timescale implies that they are due to a change in the fluid flow at the surface of the Earth's core (as has also been established through mapping the time-varying flow at the core surface8). However, little is understood of their physical origin. Here we show that geomagnetic jerks can be explained by the combination of a steady flow and a simple time-varying, axisymmetric, equatorially symmetric, toroidal zonal flow. Such a flow is consistent with torsional oscillations in the Earth's core, which are simple oscillatory flows in the core that are expected on theoretical grounds9, and observed in both core flow models10 and numerical dynamo models11.
A General Method for the Enantioselective Synthesis of Pantolactone Derivatives

An efficient enantioselective synthesis of β,β-dialkyl-γ-substituted pantolactones has been achieved utilizing the cationic [Sc((S,S)-R-pybox)](Cl)2+, R = Ph (9), t-Bu (10), complex in a catalyzed aldol reaction as the key step. The pantolactone derivatives are isolated in high enantiomeric excesses.
Multiplier ideals and integral closure of monomial ideals: An analytic approach

Proofs of two results about a monomial ideal -- describing membership in auxiliary ideals associated to the monomial ideal -- are given which do not invoke resolution of singularities. The AM--GM inequality is used as a substitute for taking a log resolution of the monomial ideal.
Intangible Assets and Firms' Disclosures: An Empirical Investigation

This study examines how research and development (R&38;D) and advertising expenditures affect firms' disclosures. Generally accepted accounting principles (GAAP) mandate that these expenditures be immediately expensed in financial reports, despite the fact that they often benefit the firm for longer periods. Prior studies find, however, that investors consider intangible assets in their valuation of firms. These studies argue that current GAAP, by not recognizing the value generated by these assets, severely impairs the usefulness of accounting reports. I investigate if firms with higher levels of R&38;D and advertising expenditures place greater reliance on voluntary, and therefore more flexible, disclosures such as voluntary publications and investor relations. Using analysts' ratings of firms' disclosures, I find that firms with higher levels of intangible assets are more likely to receive significantly higher ratings for their investor relations programs or voluntary publications than for their annual reports. These findings suggest that firms with higher levels of intangible assets emphasize supplemental disclosures because mandated accounting disclosures inadequately present their financial performance. These results have important policy implications for regulators and investors since they indicate that voluntary disclosures, which are unregulated and unaudited, are an important means of disclosure for these firms.
Synthesis and biological activity of oxo-7H-benzo[e]perimidine-4-carboxylic acid derivatives as potent, nonpeptide corticotropin releasing factor (CRF) receptor antagonists

A novel series of derivatives of oxo-7H-benzo[e]perimidine-4-carboxylic acid (I) potently displaced radioligand binding of 125I-CRF to both CRF1 and CRF2 receptors. The members of this series antagonized CRF-stimulated cAMP formation and CRF-stimulated corticotropin release from rat pituitary in vivo. These are the first nonpeptide antagonists to show activity at both CRF1 and CRF2 receptors.
Fiscal Squeeze and Social Policy during the Cardoso Administration (1995—2002):

Conventional wisdom associates the two lost decades of economic stagnation in Brazil to macroeconomic imbalances and excessive budgetary deficits. This paper suggests that, contrary to conventional wisdom, the fiscal crisis of the state in Brazil was the result of the liberalization strategy that started in 1989, and was accelerated and complemented during the Cardoso administration (1995-2002). In this view, the fiscal crisis of the State resulted from the financial liberalization of the 1990s and the increasing burden of interest payments on public debt. The interest burden, in turn, meant that fiscal spending on social policy was squeezed, a result that is common to liberalization experiences in the periphery. The amount of social spending was insufficient during the Cardoso administration, and problems were not restricted to inefficient spending.
An enantioselective synthesis of nitrogen protected 3-arylserine esters

Abstract A method for the preparation of (2R,3S) nitrogen protected arylserine esters is described. The method consists of rhodium mediated insertion of tert-butylcarbamate into the corresponding 3-keto-2-diazoester, affording the N-protected α-amino-β-ketoester, followed by asymmetric reduction/dynamic resolution to afford the corresponding N-protected 3-arylserine esters in good chemical yield, and in most cases high enantiomeric excess.
A general purpose, expandable processor for real-time computer graphics

Abstract A class of critical computer requirements for real-time scan T.V. computer graphics is examined in relation to commercially available CPU architectures. Finding general purpose processors not suited, a new processor is proposed which is designed around the concept of ‘instruction set partitioning.’ In this design, special hardware-implemented algorithms may be included in the machine instruction set, and these processors allowed to operate asynchronously from each other. The design is projected to generate a complete new frame of a color T.V. picture every 0.1-0.8 s depending on image complexity. Due to its inherent generality, the CPU may be similarly expanded to encompass a wide variety of other specialized, or real-time tasks with minimal additional hardware. The 32-bit parallel processor has a design cycle time of 100 ns and is in the price class of a minicomputer.
A note on Box′s general method of approximation for the null distributions of likelihood criteria

Abstract : Many multivariate test statistics (such as the likelihood ratio test for MANOVA) have null distributions whose moments are proportional to ratios of products of gamma functions. For any random variable W, 0 < or = W < or = 1, whose moments have the above-mentioned form, Box proposed an asymptotic expansion for the c. d. f. of W, which provides an accurate method for determining the critical constants defining rejection regions for the multivariate tests mentioned above. Although the method is useful, the calculations needed to obtain the coefficients in each asymptotic expansion must be obtained ab initio, and almost always involve cumbersome algebraic manipulations. In the present study, simplified algorithms are given for calculating the coefficients of the asymptotic expansion in the general case. In a certain special case (which includes the null distributions of the likelihood ratio criteria for MANOVA and for testing the independence among sets of variates), explicit formulas are derived for these coefficients. (Modified author abstract)
Ultrafast dynamics in pentacene and tetracene probed using optical pump-probe spectroscopy

We present room temperature photoinduced reflection and transmission measurements in pentacene and tetracene single crystals using optical pump-probe spectroscopy. Intrinsic singlet exciton dynamics and singlet fission dynamics are observed
Heart Disease in Women

In every year since 1984, cardiovascular disease has claimed the lives of more females than males. More than 450,000 women succumb to heart disease annually, and 250,000 die of coronary artery disease. Despite the proportions, most women believe they will die of breast cancer. The perception that heart disease is a man's disease and that women are more likely to die of breast cancer is alarming. Although women develop heart disease about 10 years later than men, they are likely to fare worse after a heart attack. The poorer outcomes are due, in part, to the failure to identify heart attack symptoms. Approximately 35% of heart attacks in women are believed to go unnoticed or unreported. However, because of increased age, women are more likely to have co-morbid diseases such as diabetes and hypertension. In women, not only is "tightness" or discomfort in the chest a warning sign, but in addition, nausea and dizziness are common indicators of myocardial ischemia. Other symptoms include breathlessness, perspiration, a sensation of fluttering in the heart, and fullness in the chest. In comparison to men, women are less likely to undergo tertiary care interventions such as cardiac catheterization, angioplasty, thrombolytic therapy, and bypass surgery; to participate in cardiac rehabilitation; and to return to work full-time after myocardial infarction. In the past, most research about treatments for heart disease focused on men, and gender differences have been ignored. Recent studies are enrolling enough women to test if there are differences between men and women in outcomes. One of the major areas of research relates to estrogen and hormonal replacement therapy to reduce the relative risk of heart attack and stroke. The Women's Health Initiative is a major NIH-sponsored trial that addresses the issue of primary prevention of cardiac disease by hormonal replacement therapy. The results will be available in 2004. The Heart Estrogen/Progestin Replacement Study (HERS), disappointingly, did not show a significant reduction of coronary events in women taking hormonal replacement therapy, nor did the Estrogen Replacement and Atherosclerosis (ERA) trial of 309 postmenopausal women who underwent coronary angiography. New insight into the role of vitamins, phytoestrogens and other natural sources, and selective estrogen receptor modulators may provide other options for management. Until then, modification of risk factors and healthy life style choices are recommended for reducing the risk of cardiac disease. In fact, the key to a healthy heart in the year 2000 appears closely tied to life style choices. Prevention of disease is the key, and current recommendations are simply to stop smoking, or do not start; treat and control blood pressure >140/90 mm Hg; manage elevated lipids by diet, exercise, and cholesterol-lowering medications (if necessary); treat diabetes; lose weight so that BMI is <25; walk for 20-30 minutes at least three times a week; and take an aspirin tablet daily.
Dynamic power allocation and routing for time-varying wireless networks

We consider dynamic routing and power allocation for a wireless network with time-varying channels. The network consists of power constrained nodes that transmit over wireless links with adaptive transmission rates. Packets randomly enter the system at each node and wait in output queues to be transmitted through the network to their destinations. We establish the capacity region of all rate matrices (/spl lambda//sub ij/) that the system can stably support-where /spl lambda//sub ij/ represents the rate of traffic originating at node i and destined for node j. A joint routing and power allocation policy is developed that stabilizes the system and provides bounded average delay guarantees whenever the input rates are within this capacity region. Such performance holds for general arrival and channel state processes, even if these processes are unknown to the network controller. We then apply this control algorithm to an ad hoc wireless network, where channel variations are due to user mobility. Centralized and decentralized implementations are compared, and the stability region of the decentralized algorithm is shown to contain that of the mobile relay strategy developed by Grossglauser and Tse (2002).
The capitalist world aggregate supply and demand model for natural uranium

Seemingly unrelated regression associating U supply and demand to own price, net nuclear electric consumption, generating capacity, competing fuel prices, and electricity prices is postulated. Coal prices are found to influence uranium price significantly. Composite energy prices affect uranium demand via either nuclear electric consumption or nuclear generating capacity. Electricity prices affect uranium demand directly in a negative fashion.
Terahertz electronics: The last frontier

Summary form only given. Sensors add intelligence to systems which represent a broad class of devices incorporating functionalities like sensing, actuation, and control. They are the core of smart components and subsystems; then, the challenge in the realization of such smart systems goes beyond the design of the individual components and subsystems and consists of accommodating a multitude of functionalities, technologies, and materials to play a key role to augment our daily life.
Artifact systems with data dependencies and arithmetic

We study the static verification problem for data-centric business processes, specified in a variant of IBM's “business artifact” model. Artifacts are records of variables that correspond to business-relevant objects and are updated by a set of services equipped with pre- and postconditions, that implement business process tasks. The verification problem consists in statically checking whether all runs of an artifact system satisfy desirable properties expressed in a first-order extension of linear-time temporal logic. Previous work identified the class of guarded artifact systems and properties, for which verification is decidable. However, the results suffer an important limitation: they fail in the presence of even very simple data dependencies or arithmetic, both crucial to real-life business processes. In this article, we extend the artifact model and verification results to alleviate this limitation. We identify a practically significant class of business artifacts with data dependencies and arithmetic, for which verification is decidable. The technical machinery needed to establish the results is fundamentally different from previous work. While the worst-case complexity of verification is nonelementary, we identify various realistic restrictions yielding more palatable upper bounds.
Object recognition using coding schemes

A new technique for recognizing two-dimensional objects independent of scale and orientation is presented. This technique's performance on real imagery of tactical military targets, both occluded and nonoccluded, is evaluated. The robustness of this method with respect to partial occlusion is shown. The relatively small storage requirements and fast search time make it an attractive candidate for real-time applications.
SARLAC: a relativistic electron beam code

Abstract SARLAC is a particle simulation code for studying the propagation of ultra-relativistic electron beams. It is used to study the nonlinear evolution of the resistive hose instability. We have developed a fast, semi-implicit, iterative field solver which allows us to include a large number of Fourier modes in the azimuthal direction. The solver iterates about a solution of the field equations dominated by the axisymmetric ( m =0) conductivity. This technique has proved to be quite successful. We compare some results of the code with those obtained from a linearized hose simulation code and show differences when the hose oscillations reach large amplitude.
Catalytic bismetallative multicomponent coupling reactions: scope, applications, and mechanisms

Catalytic reactions have played an indispensable role in organic chemistry for the last several decades. In particular, catalytic multicomponent reactions have attracted significant attention due to their efficiency and expediency towards complex molecule synthesis. The presence of bismetallic reagents (e.g. B–B, Si–Si, B–Si, Si–Sn, etc.) in this process renders the products enriched with various functional groups and multiple stereocenters. For this reason, catalytic bismetallative coupling is considered an effective method to generate the functional and stereochemical complexity of simple hydrocarbon substrates. This review highlights key developments of transition-metal catalyzed bismetallative reactions involving multiple π components. Specifically, it will highlight the scope, synthetic applications, and proposed mechanistic pathways of this process.
A design science based evaluation framework for patterns

Patterns were originally developed in the field of architecture as a mechanism for communicating good solutions to recurring classes of problems. Since then, many researchers and practitioners have created patterns to describe effective solutions to problems associated with disparate areas such as virtual project management, human-computer interaction, software development and engineering, and design science research. We believe that the development of patterns is a design science activity in which an artifact (i.e., a pattern) is created to communicate about and improve upon the current state-of-practice. Design science research has two critical components, creation and evaluation of an artifact. While many patterns have been created, few, if any, have been evaluated in this sense. In this paper, we propose a framework to evaluate patterns in any domain and provide examples of how to use the evaluation framework. This process of evaluation could help researchers refine extant patterns and improve the possibility of creating sustainable best practices for a given domain. We believe this evaluation framework begins an important dialogue related to the evaluation of patterns as artifacts of design science research. We draw upon the literature associated with patterns, evaluation of design science research, and research methods to develop this framework for evaluating patterns in a more consistent and rigorous manner.
Discovery of the gold isotopes

Thirty-six gold isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
Periurethral Collagen Injection for Male and Female Sphincteric Incontinence: Indications, Techniques, and Result

Intrinsic sphincter deficiency is characterized by a poorly functioning intrinsic urethral sphincter, which leaks urine at relatively low pressures. Patients with this sort of incontinence are candidates for collagen implant therapy. Collagen is injected in the region of the bladder neck with success, depending on the precise placement of the collagen. There is generally a need to implant more collagen into men. The percentage of patients showing improvement in their incontinence after therapy is 58-100%. Over time the collagen is absorbed and there is a need to repeat the treatment. Collagen increases the abdominal leak-point pressure without reducing the flow rate or increasing the residual volume. Treatment failure does not prevent the performance of other procedures.