cssi/SciSciGPT-SciSciNet huggingface dataset:
Insider Lending and Bank Ownership: The Case of Russia☆

Abstract We develop a model of insider lending in which a borrower can give incentives to a bank manager to misuse his right of control by extending a loan at favorable rates to the borrower at the expense of the equity value of the bank. The model explains why insider loans are often made to borrowing firms that are also large shareholders of the bank. Although in principal every borrower could bribe the bank manager for insider loans, large shareholders have the power to fire the bank manager and will use this power if the manager extends insider loans to others. Therefore, a bank manager has an incentive to favor large shareholders when engaging in insider lending. Using a World Bank survey of Russian enterprises, we provide support for our model. We find that Russian firms and banks engaged in insider lending on the basis of loan volume. To limit insider lending, we propose proper incentives for bank managers, such as high penalties or equity incentive schemes. J. Comp. Econ. , June 2001 29 (2), pp. 207–229. The World Bank, 1818 H Street, NW, Washington, DC 20433. Copyright 2001 Academic Press. Journal of Economic Literature Classification Numbers: D82, G21, G32, G38, P50.
Performance Characteristics Of A Translate-Rotate Head Scanner With Xenon Detectors

The performance and dosimetric characteristics of the first U.S.-installed hybrid head scanner developed commercially by CGR Medical Corporation have been evaluated. Using a translate-rotate motion with a xenon gas detector array, the scanner produces excellent low contrast resolution at low dose levels (single slice surface dose of 1 rad). Console selection of scanning parameters, viz.: scan time, kV, mA, beam filtration, slice width, and pixel size permits optimization of image quality for various exams. For optimizing either spatial or low contrast resolution, a push-button choice of reconstruction algorithms is available. Using the American Association of Physicists in Medicine (AAPM) computed tomography (CT) phantom, spatial resolution and line spread functions for both algorithms were determined from the graphical display of CT numbers. Low contrast resolution was measured at various contrast levels as a function of kV, dose, beam width, pixel size, and algorithm. Values for noise (a) were also recorded for these scanning parameters. Patient dose distributions for various operator-selectable beam widths (3, 6, 9 mm) were obtained using film and TLDs. CT number linearity and contrast scale were determined using different plastic rods.
Services and the Business Models of Product Firms: An Empirical Analysis of the Software Industry

Some product firms increasingly rely on service revenues as part of their business models. One possible explanation is that they turn to services to generate additional profits when their product industries mature and product revenues and profits decline. We explore this assumption by examining the role of services in the financial performance of firms in the prepackaged software products industry Standard Industrial Classification code 7372 from 1990 to 2006. We find a convex, nonlinear relationship between a product firm's fraction of total sales coming from services and its overall operating margins. As expected, firms with a very high level of product sales are most profitable, and rising services are associated with declining profitability. We find, however, that additional services start to have a positive marginal effect on the firm's overall profits when services reach a majority of a product firm's sales. We show that traditional industry maturity arguments cannot fully explain our data. It is likely that changes in both strategy and the business environment lead product firms to place more emphasis on services. This paper was accepted by Christoph Loch, R&D and product development.
Synthesis and structures of isomerically pure bis-(alkylbenzo) crown ethers

Abstract A convenient method for the synthesis of bis-(4-alkyl-2-hydroxyphenoxy) alkoxy ethers, precursors to highly lipophilic, alkylbenzo-substituted crown ethers, is described. Thirteen isomerically-pure, bis-t-alkylbenzo crown ethers were prepared. The solid-state structures of three representative, bis-t-octylbenzo crown ethers are reported, representing the first structures ever reported for t-octylbenzocrown ethers.
Ordered BaAl4-Type Variants in the BaAuxSn4–x System: A Unified View on Their Phase Stabilities versus Valence Electron Counts

Three ordered structures of the tetragonal BaAl4 type were identified in the Ba-Au-Sn system, from which a unified view of the interplay between the valence electron counts (VECs) and phase stabilities of these three types of derivatives can be developed. The BaNiSn3 (I4mm), ThCr2Si2 (I4/mmm), and CaBe2Ge2 (P4/nmm) type BaAu(x)Sn(4-x) phases occurred respectively at x = 0.78(1)-1, 1.38(1)-1.47(1), and 1.52(1)-2.17(1), consistent with theoretical atomic "coloring" analyses that reveal an optimal VEC of ∼14 for the ThCr2Si2 type but larger and smaller values respectively for the BaNiSn3- and CaBe2Ge2-type structures.
Effect of growth conditions on the conductivity of Mg doped p‐type GaN by Molecular Beam Epitaxy

The performance of III–V nitride heterostructure bipolar transistors has been limited by highly resistive p-type layers, in addition to difficulties associated with a precise p–n junction placement at the emitter-base heterojunction due to the Mg-memory effect during growth by Metal-Organic Chemical Vapor Deposition. The problem of precise p–n heterojunction placement can be solved by Molecular Beam Epitaxy growth. To investigate this possibility, in this work, we present a comprehensive study of the effect of III/V ratio, growth temperature, and Mg doping on the resistivity of Mg doped GaN layers grown by Molecular Beam Epitaxy. N2-rich growth conditions are found to lead to a temperature- independent low hole mobility, as opposed to Ga-rich growth conditions that lead to higher hole mobilities that vary with temperature. In addition, the growth temperature, Ga flux, and Mg flux windows leading to the highest p-type conductivity are identified. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Adjacent state issues for the UNITED STATES in establishing an exclusive economic zone: The cases of Canada and Mexico

Abstract This paper will analyze and evaluate the issues that might emerge between the United States and both Canada and Mexico in the establishment of adjacent exclusive economic zones (EEZs). Given the ambiguity of the U.N. Convention language and historic differences in approach to law of the sea issues, it is likely that there will be differences in how each of these countries will manage and regulate activities within their respective zones. Since many of the resources and activities are transboundary in nature, the potential for conflict between states exists. The paper will serve to highlight existing areas of conflict and will evaluate the potential for future disagreements.
When are comparative dynamics monotone

Abstract A common problem in dynamic economic theory is to determine when an increase in a parameter and/or an initial condition increases the future dynamics of a theoretical economy. This paper provides conditions that are necessary and sufficient for making statements of this type. The result is applicable to situations with a single agent or with many agents in the presence or absence of uncertainty. The result holds for general notions of what it means for a parameter, an initial condition or even the dynamics of a model to be increasing.
EFFECT OF APPLIED FIELDS ON THE OPTICAL PROPERTIES OF COLOR CENTERS

A theoretical analysis is made of the effect of an external perturbation, such as an electric field, magnetic field, or stress, on the optical properties of color centers. Our analysis is restricted to centers with orbital singlet ground states. It is especially applicable to centers with orbitally degenerate excited states which are interacting strongly with the lattice, such as the $F$ center in the alkali halides. We describe the changes in the optical properties by computing the changes in the moments of the optical absorption line shape that occur when the external perturbation is applied. The changes in the zeroth, first, second, and third moments may be computed quite simply. Although this does not give the detailed change in the line shape, it provides a precise method for evaluating parameters of the center, such as the spin-orbit coupling constant of the excited state of the $F$ center. We use our method of moments to analyze experiments on the circular dichroism, Faraday rotation, Stark effect, Voigt effect, and stress-induced dichroism of the $F$ center and the circular dichroism of the $A$ center. By analyzing the circular-dichroism or stress-induced-dichroism data for an $F$ band, we are able for the first time to evaluate the contributions to the broadening of the band by the cubic and noncubic lattice-vibrational modes. We have analyzed the data of Margerie and Romestain on the circular dichroism of the $F$ band in CsBr and CsCl. Our analysis resolves the discrepancy between their two methods of determining the spin-orbit splitting (measurement of the peak separation and measurement of the circular dichroism), and shows that the splitting arises from a combination of a large spin-orbit coupling and a large noncubic lattice-vibrational interaction.
Electron-Positron Flows around Magnetars

The twisted magnetospheres of magnetars must sustain a persistent flow of electron-positron plasma. The flow dynamics is controlled by the radiation field around the hot neutron star. The problem of plasma motion in the self-consistent radiation field is solved using the method of virtual beams. The plasma and radiation exchange momentum via resonant scattering and self-organize into the radiatively locked outflow with a well-defined, decreasing Lorentz factor. There is an extended zone around the magnetar where the plasma flow is ultra-relativistic; its Lorentz factor is self-regulated so that it can marginally scatter thermal photons. The flow becomes slow and opaque in an outer equatorial zone, where the decelerated plasma accumulates and annihilates; this region serves as a reflector for the thermal photons emitted by the neutron star. The e ± flow carries electric current, which is sustained by a moderate induced electric field. The electric field maintains a separation between the electron and positron velocities, against the will of the radiation field. The two-stream instability is then inevitable, and the induced turbulence can generate low-frequency emission. In particular, radio emission may escape around the magnetic dipole axis of the star. Most of the flow energy is converted to hard X-ray emission, which is examined in an accompanying paper.
Borate complexes of benzohydroxamic acid and some of its derivatives.

Abstract Ultraviolet spectrophotometric measurements in dilute aqueous solution give p K a values of 8.78, 8.27, 8.96 and 8.68, respectively, for benzohydroxamic, N -phenylbenzohydroxamic, p -methoxybenzohydroxamic and N -methyl- p -methoxybenzohydroxamic acids. The acids carrying no substituent on nitrogen form 1:1 complexes with boric acid according to the general equation RCONHOH + H 3 BO 3 → (1:1 complex) − + H + . Equilibrium constants (log K ) were found to be −5.70 for benzohydroxamic acid and −5.8 for p -methoxybenzohydroxamic acid. The complexes behave as very weak monoprotic acids and decompose at high pH to yield borate ions and the corresponding hydroxamate ions. The N -substituted hydroxamic acids showed no reaction with boric acid under the same conditions.
Minimal cost of a Brownian risk without ruin

Abstract In this paper, we study an optimal stochastic control problem for an insurance company whose surplus process is modeled by a Brownian motion with drift (the diffusion approximation model). The company can purchase reinsurance to lower its risk and receive cash injections at discrete times to avoid ruin. Proportional reinsurance and excess-of-loss reinsurance are considered. The objective is to find an optimal reinsurance and cash injection strategy that minimizes the total cost to keep the surplus process non-negative (without ruin). Here the cost function is defined as the total discounted value of the injections. The minimal cost function is found explicitly by solving the according quasi-variational inequalities (QVIs). Its associated optimal reinsurance-injection control policy is also found.
Matching through position auctions

Abstract Using a mechanism design framework, we characterize how a profit-maximizing intermediary can design matching markets when each agent is privately informed about his quality as a partner. Sufficient conditions are provided that ensure a version of positive assortative matching (what we call truncated positive assortative matching ) maximizes profits. Under these conditions, all-pay position auctions always implement the profit-maximizing allocation. Winners-pay position auctions, however, only do so in sufficiently large markets.
Two Moderate-redshift Analogs to Compact Massive Early-type Galaxies at High Redshifts

From a search of a portion of the sky covered by the Sloan Digital Sky Survey and UKIRT Infrared Sky Survey databases, we have located two galaxies at z {approx} 0.5 that have properties similar to those of the luminous passive compact galaxies found at z {approx} 2.5. From Keck moderate-resolution spectroscopy and laser-guided adaptive-optics imaging of these galaxies, we can begin to put together a more detailed picture of what their high-redshift counterparts might be like. Spectral-synthesis models that fit the u to K photometry also seem to give good fits to the spectral features. From these models, we estimate masses in the range of 3-4 x 10{sup 11} M {sub sun} for both galaxies. Under the assumption that these are spheroidal galaxies, our velocity dispersions give estimated masses about a factor of 3 smaller. However, our high-resolution imaging data indicate that these galaxies are not normal spheroids, and the interpretation of the kinematic data depends critically on the actual morphologies and the nature of the stellar orbits. While recent suggestions that the population of high-redshift compact galaxies is present locally as the inner regions of local massive elliptical galaxies are quite plausible, the peak mass surface densities ofmore » the two galaxies we discuss here appear to be up to a factor of 10 higher than those of the highest density local ellipticals, assuming that our photometric masses are roughly correct. It thus seems possible that some dynamical 'puffing-up' of the high-redshift galaxies might still be required in this scenario.« less
Bicovariant quantum algebras and quantum Lie algebras

A bicovariant calculus of differential operators on a quantum group is constructed in a natural way, using invariant maps from Fun $$(\mathfrak{G}_q )$$ toU q g, given by elements of the pure braid group. These operators—the “reflection matrix”Y≡L + SL − being a special case—generate algebras that linearly close under adjoint actions, i.e. they form generalized Lie algebras. We establish the connection between the Hopf algebra formulation of the calculus and a formulation in compact matrix form which is quite powerful for actual computations and as applications we find the quantum determinant and an orthogonality relation forY inSO q (N).
A simple criterion for effects beyond hard thermal loops

Abstract Thermal amplitudes with ultrasoft momenta, which are not accessible by standard methods of perturbation theory, have recently attracted a lot of interest. However, the comparison of external momenta with the ultrasoft scale g 2 T ln(1/ g ) is a too crude criterion, since amplitudes with hard external momenta can also be non perturbative, if these momenta are close enough to the light-cone. In this letter, I give a more refined criterion to decide if an amplitude is non perturbative, that applies to all situations. In physical terms, this condition states that non-perturbative effects appear if the particles running in loops have to travel distances larger than their mean free path.
Internal vs. external learning in new product development: effects on speed, costs and competitive advantage

The purpose of this study was to investigate how different technology sourcing strategies throughout the new product development process influenced innovation speed, development costs, and competitive advantage. We studied 75 new product development projects from ten large, U.S.-based companies in several industries. Results indicated that: (1) more external sourcing during the early (i.e., idea generation) stage was related with lower competitive success; (2) more external sourcing during the later (i.e., technological development stage was related with slower innovation speed; and (3) development costs tended to rise with greater reliance on external sources of technology, but this result was not statistically significant.
Kuznets and Pasinetti on the study of structural transformation: Never the Twain shall meet?

Abstract The main characteristics of the economic growth of nations are a sustained increase in the growth of output and factor productivity and a widespread process of structural transformation. In this paper I contrast two of the few important authors that do not ignore structural change: Kuznets and Pasinetti. Over several decades the two approaches have developed in an almost orthogonal manner. I discuss the reasons and evaluate the relevance of the approaches for the study of economic development.
Mercury: The Dark-Side Temperature

Mercury planet average dark side temperature indicating top surface layer similarity with moon
Duality and self-duality (energy reflection symmetry) of quasi-exactly solvable periodic potentials

Abstract A class of spectral problems with a hidden Lie-algebraic structure is considered. We define a duality transformation which maps the spectrum of one quasi-exactly solvable (QES) periodic potential to that of another QES periodic potential. The self-dual point of this transformation corresponds to the energy-reflection symmetry found previously for certain QES systems. The duality transformation interchanges bands at the bottom (top) of the spectrum of one potential with gaps at the top (bottom) of the spectrum of the other, dual, potential. Thus, the duality transformation provides an exact mapping between the weak coupling (perturbative) and semiclassical (nonperturbative) sectors.
Geometrically Based Statistical Model for Polarized Body-Area-Network Channels

A new geometry-based channel model is proposed for wide-band polarized body-area-network channels consisting of four propagation modes, i.e., cylindrical surface scattering (CSS) for above-ground off-body scattering (BS), BS for body diffracted and on-BS, ground scattering (GS), and line-of-sight. A conservation-of-polarization plane methodology is used for the CSS and GS propagation modes. For the BS propagation mode, a geometrical theory of diffraction is used and related to CSS. The channel cross-polarization discrimination (XPD) and time-frequency correlation function (TF-CF) are derived from the model. Comparisons of the XPD and the TF-CF that are obtained from the model (with appropriate physical parameters) and those obtained from wide-band measurements at 13-GHz are in good agreement. We observed the GS propagation mode to be the dominant mode in our experiments. The azimuth angle of arrival (AAoA) of a ground reflected wave is shown in theory to have a significant effect on the XPD.
Using cluster studies to approach the electronic structure of bulk water: Reassessing the vacuum level, conduction band edge, and band gap of water

Aqueous cluster studies have lead to a reassessment of the electronic properties of bulk water, such as band gap, conduction band edge, and vacuum level. Using results from experimental hydrated electron cluster studies, the location of the conduction band edge relative to the vacuum level (often called the V0 value) in water has been determined to be −0.12 eV⩽V0⩽0.0 eV, which is an order of magnitude smaller than most experimental values in the literature. With V0=−0.12 eV and making use of the calculated solvation energy of OH in water, the band gap of water is determined to be 6.9 eV. Again, this is smaller than many literature estimates. In the course of this work, it is shown that due to water’s ability to reorganize about charge (1) photoemission thresholds of water or anionic defects in water do not determine the vacuum level, and (2) there is almost no probability of accessing the bottom of the conduction band of water with a vertical/optical process from water’s valence band. The results are pres...
Decomposition kinetics of lithium amide for hydrogen storage materials

Abstract The kinetic behavior of LiNH 2 decomposition by ammonia release was quantified using thermogravimetric analysis (TGA). While not itself a hydrogen storage material, LiNH 2 is a primary component of the hydrided state in Li–N–H storage materials based on Li 3 N or Li 2 NH. Its decomposition by ammonia release, and consequent degradation of the hydrogen storage capacity, has important implications for the durability of Li–N–H storage systems. LiNH 2 from two commercial lots and one batch prepared at GM R&D were ball milled for 10 or 20 min to obtain fine LiNH 2 powders. Kinetic parameters were extracted from sets of TGA weight loss curves taken at different heating rates. The activation energy for the decomposition reaction was determined to be about 128 kJ/mole, virtually independent of the source and purity of the LiNH 2 , its stoichiometry, ball milling time, and TGA sample size. The reaction rate was found to depend on the sample size as a consequence of the very low NH 3 –LiNH 2 equilibrium vapor pressure at temperatures below 300 °C. Larger samples produce a local concentration of NH 3 high enough to inhibit further reaction. Direct isothermal measurements of the initial reaction rates at temperatures between 200 and 300 °C agree well with the values calculated from the heating rate-derived kinetic parameters. The durability of Li–N–H for hydrogen storage was estimated from the measured kinetic parameters by calculating the time required to decompose 20% of the initial LiNH 2 , as a function of the operating temperature. The predicted lifetime falls below 10 5 min for operating temperatures in excess of ∼160 °C.
On the Properties of Thermal Disk Winds in X-ray Transient Sources: A Case Study of GRO J1655–40

We present the results of hydrodynamical simulations of the disk photosphere irradiated by strong X-rays produced in the innermost part of the disk of an accreting black hole. As expected, the irradiation heats the photosphere and drives a thermal wind. To apply our results to the well-studied X-ray transient source GRO J1655–40, we adopted the observed mass of its black hole and the observed properties of its X-ray radiation. To compare the results with the observations, we also computed transmitted X-ray spectra based on the wind solution. Our main finding is that the density of the fast-moving part of the wind is more than 1 order of magnitude lower than that inferred from the observations. Consequently, the model fails to predict spectra with line absorption as strong and as blueshifted as those observed. However, despite the thermal wind being weak and Compton thin, the ratio between the mass-loss rate and the mass-accretion rate is about seven. This high ratio is insensitive to the accretion luminosity, in the limit of lower luminosities. Most of the mass is lost from the disk between 0.07 and 0.2 of the Compton radius. We discovered that beyond this range the wind solution is self-similar. In particular, soon after it leaves the disk, the wind flows at a constant angle with respect to the disk. Overall, the thermal winds generated in our comprehensive simulations do not match the wind spectra observed in GRO J1655–40. This supports the conclusion of Miller et al. and Kallman et al. that the wind in GRO J1655–40, and possibly in other X-ray transients, may be driven by magnetic processes. This in turn implies that the disk wind carries even more material than our simulations predict and as such has a very significant impact on the accretion disk structure and dynamics.
A theoretical study of acetylene, ethylene, and cyclopropene additions to benzo[b]- and benzo[c]-fused heterocycles

Abstract The reactivity of benzo[b]- and benzo[c]-fused heterocycles as dienes for Diels-Alder reactions were evaluated on the basis of Frontier Molecular Orbital (FMO) energy gaps between reactants, necessary FMO changes for the transformation of reactants into transition state structures, uniformity of bond orders of heterocyclic rings, and uniformity of bond orders of the six-membered cyclic transition state structures All of these values were obtained with AM1 semiempirical methods. The selectivity of the cycloaddition reaction was also judged with Secondary Orbital Interactions (SOI) between two reactant moieties in isomeric transition state structures. For every possible reaction pathway, AM1 and B3LYP/AM1 energies were evaluated. The relative reactivity and selectivity obtained by computing activation barriers for these reactions were in full agreement with our qualitative studies as well as with experimental results. The usefulness of the FMO and bond order uniformity approach for the study of the Diels-Alder reaction was discussed.
Flight Dynamics and Hybrid Adaptive Control of Damaged Aircraft

This paper presents a recent study to investigate flight dynamics and adaptive control methods for stability and control recovery of a damaged generic transport aircraft. Aerodynamic modeling of damage effects is performed using an aerodynamic code to assess changes in the stability and control derivatives of the damaged aircraft. Flight dynamics for a general aircraft are developed to account for changes in aerodynamics, mass properties, and the center of gravity that can compromise the stability of the damaged aircraft An iterative trim analysis is developed to compute incremental trim states. A neural network hybrid direct-indirect adaptive flight control is developed for the stability augmentation control of the damaged aircraft. The proposed method performs an online estimation of damaged plant dynamics to improve the command tracking performance in conjunction with a direct adaptive controller. The plant estimation is based on two approaches: 1) an indirect adaptive law derived from the Lyapunov stability theory to ensure that the tracking error is bounded, and 2) a recursive least-squares method that minimizes the modeling error. Simulations show that the hybrid adaptive controller can provide a significant improvement in the tracking performance over a direct adaptive controller working alone.
Rational pattern classification when very little is known

Abstract The problem of pattern classification when very little is known about the pattern source is structured through a set of axioms describing desirable properties for a classifier that involve no probabilistic assumptions or hypotheses. The derived classifier is then studied under the hypothesis that the pattern source is probabilistic and its long-run performance found to strongly converge to that of the Bayes classifier under reasonable restrictions. The sparse results of a pilot study on the comparative small sample performance of the derived classifier are found to be encouraging but not definitive. This work is an outgrowth of previous work on extrapolation when little is known
Simulation on three sizes of computers—An evaluation

Abstract Discrete simulation modeling is a powerful tool used for evaluation and analysis. While it has been used extensively on mainframe computers, for a number of reasons it has not to-date been widely used on small computers. This paper addresses the issue of simulation on small computers by answering the following question: “Are microcomputers powerful enough to process a highly iterative simulation model in an accurate, timely, and cost-effective manner?”
Manifestly supersymmetric Lax integrable hierarchies

Abstract A systematic method of constructing manifestly supersymmetric 1 + 1-dimensional KP Lax hierarchies is presented. Closed expressions for the Lax operators in terms of superfield eigenfunctions are obtained. All hierarchy equations being eigenfunction equations are shown to be automatically invariant under the (extended) supersymmetry. The supersymmetric Lax models existing in the literature are found to be contained (up to a gauge equivalence) in our formalism.
Converging scientific fields and new technological paradigms as main drivers of the division of scientific labour in drug discovery process: the effects on strategic management of the R&D corporate change

The thesis of this study is that the convergence of genetics, genomics and proteomics spurs new technological paradigms in medicine, which are generating a R&D corporate change: division of scientific labour of the drug discovery process by strategic alliances among firms in order to reinforce the integrative capabilities in different biomedical research fields and collective and cumulative learning between in-house R&D and external sources of innovation. This study shows, by key a case study of pharmaceutical companies, as scientific and technological paradigms in medicine are main drivers of industrial and R&D corporate change to enhance and accelerate the discovery process of ground-breaking drugs for more and more personalised healthcare.
A weak Galerkin finite element method for second-order elliptic problems

This paper introduces a finite element method by using a weakly defined gradient operator over generalized functions. The use of weak gradients and their approximations results in a new concept called discrete weak gradients which is expected to play an important role in numerical methods for partial differential equations. This article intends to provide a general framework for managing differential operators on generalized functions. As a demonstrative example, the discrete weak gradient operator is employed as a building block in the design of numerical schemes for a second order elliptic problem, in which the classical gradient operator is replaced by the discrete weak gradient. The resulting numerical scheme is called a weak Galerkin (WG) finite element method. It can be seen that the weak Galerkin method allows the use of totally discontinuous functions in the finite element procedure. For the second order elliptic problem, an optimal order error estimate in both a discrete H^1 and L^2 norms are established for the corresponding weak Galerkin finite element solutions. A superconvergence is also observed for the weak Galerkin approximation.
C. SYLVESTER WHITAKER, Jr.

C. Sylvester Whitaker, Jr., passed away on November 29, 2008, in Waterville, Maine, after a long battle with cancer. He was 73 years old.
Note on the Chromosphere Spectrum

WITH the new spectroscope of the Halsted Observatory, which has a 5-inch Rowland grating of 20,000 lines to the inch, I have repeatedly observed of late that the bright chromosphere line, Angstrom 6676˙9 (No. 2 in my catalogue of chromosphere lines), is not coincident with the corresponding dark line of the solar spectrum, but is less refrangible by about one-third of a unit of Rowland's scale. This chromosphere line, therefore, can no longer be ascribed to iron, but must be due to some other substance as yet undetermined.
Oxidative Degradation of Castanospermine

Abstract Oxidation of castanospermine (1) (HIO4) and its 6-O-acetyl derivative 7 [Pb(OAc)4], followed by reduction and acetylation, were reported. A mechanism is proposed for the novel Pb(OAc)4 oxidation of a β-tertiary amino alcohol.
Very dusty galaxies

The existence of a significant population of dust shrouded galaxies that do not emit much optical light but instead are primarily infrared sources is considered. It is noted that if very dusty galaxies are assumed to have a luminosity function similar to that of normal galaxies, then current observations seem to show that there are not more dusty galaxies than normal objects. Until more extensive infrared observations are obtained, however, it seems at least possible, though perhaps unlikely, that there are in fact a significant number of dusty galaxies.
Wavepacket Preservation Under Nonlinear Evolution

We study nonlinear systems of hyperbolic PDE’s in \({\mathbb{R}}^{d}\), the hyperbolicity is understood in a wider sense, namely multiple roots of the characteristic equation are allowed and dispersive equations are permitted. They describe wave propagation in dispersive nonlinear media such as, for example, electromagnetic waves in nonlinear photonic crystals. The initial data is assumed to be a finite sum of wavepackets referred to as a multi-wavepacket. The wavepackets and the medium nonlinearity are characterized by two principal small parameters β and \(\varrho\) where: (i) \(\frac{1}{\beta}\) is a factor describing spatial extension of involved wavepackets; (ii) \(\frac{1}{\varrho}\) is a factor describing the relative magnitude of the linear part of the evolution equation compared to its nonlinearity. A key element in our approach is a proper definition of a wavepacket. Remarkably, the introduced definition has a flexibility sufficient for a wavepacket to preserve its defining properties under a general nonlinear evolution for long times. In particular, the corresponding wave vectors and the band numbers of involved wavepackets are “conserved quantities”. We also prove that the evolution of a multi-wavepacket is described with high accuracy by a properly constructed system of envelope equations with a universal nonlinearity. The universal nonlinearity is obtained by a time averaging applied to the original nonlinearity, in simpler cases the averaged system turns into a system of Nonlinear Schrodinger equations.
Property Rights and Urban Development: Initial Title Quality Matters Even When it No Longer Matters

Formal title to property allows owners to borrow for investing in improvements. Title legalization laws, however, appear to yield only modest increases in housing quality in developing countries. We offer a simple model in which squatters initially balance initial investment in low quality structures to reduce the risk of eviction against the future effect of increasing the marginal cost of improving quality. The effort to secure initial possession thereby creates a legacy effect, reducing subsequent investments in housing quality. Empirical tests using Bolivian data yield results consistent with the legacy theory: initial title risk suppresses long run housing quality.
Accumulation of butyltins in muscle tissue of chinook salmon reared in sea pens treated with tri-n-butyltin

Abstract Muscle tissue of chinook salmon, Oncorhyncus tshawytscha , reared for 3 to 19 months in sea pens treated with an antifouling biocide, tri-n-butyltin (TBT), contained organotin concentrations of 0.28–0.90 μg g −1 (as TBT). Organotins are present in some pen-reared salmon sold in the United States: eleven of 15 salmon advertised as aquaculture products and purchased from public markets contained organotin concentrations of 0.081–0.20 μg g −1 . Most common cooking practices do not effectively destroy or remove butyltins from salmon muscle tissue. We believe this is the first evidence of entry of organotins into the human diet in the United States.
A connectedness result in positive characteristic

Let (R,m) be a complete local ring of dimension at least two, which contains a separably closed coefficient field of positive characteristic. Using a vanishing theorem of Peskine-Szpiro, Lyubeznik proved that the local cohomology module H 1 m (R) is Frobenius-torsion if and only if the punctured spectrum of R is connected in the Zariski topology. We give a simple proof of this theorem and, more generally, a formula for the number of connected components in terms of the Frobenius action on H 1 m (R).
Integration of RFID and computer vision for remote object perception for individuals who are blind

Over the last few years, Radio-Frequency Identification (RFID) technology has gained popularity for use in assistive technology for individuals who are blind. Recently, RFID-based wearable assistive devices have been developed for individuals who are blind to assist with navigation or remote object perception. However, RFID-based assistive technology suffers from two major drawbacks: (1) information overload in environments with many tagged objects, and (2) usability issues in untagged environments. In this paper, we propose a framework for integrating RFID and computer vision in assistive devices for remote object perception to overcome the aforementioned limitations. Computer vision enables content selection to help prevent information overload and provide users with only relevant information found through RFID. Moreover, computer vision can be used to learn a mapping between visual data and object features as acquired through tags, which will enable computer vision to replace RFID in untagged environments.
Evaluating compressive sampling strategies for performance monitoring of data centers

Performance monitoring of data centers provides vital information for dynamic resource provisioning, fault diagnosis, and capacity planning decisions. However, the very act of monitoring a system interferes with its performance, and if the information is transmitted to a monitoring station for analysis and logging, this consumes network bandwidth and disk space. This paper proposes a low-cost monitoring solution using compressive sampling — a technique that allows certain classes of signals to be recovered from the original measurements using far fewer samples than traditional approaches — and evaluates its ability to measure typical signals generated in a data-center setting using a testbed comprising the Trade6 enterprise application. The results open up the possibility of using low-cost compressive sampling techniques to detect performance bottlenecks and anomalies that manifest themselves as abrupt changes exceeding operator-defined threshold values in the underlying signals.
The First Direct and Enantioselective Cross-Aldol Reaction of Aldehydes

The first enantioselective catalytic direct cross-aldol reaction that employs nonequivalent aldehydes has been accomplished using proline as the reaction catalyst. Structural variation in both the aldol donor (R1 = Me, n-Bu, Bn, 91 to >99%) and aldol acceptor (R2 = I-Pr, I-Bu, c-C6H11, Et, Ph, 97−99% ee) are possible while maintaining high reaction efficiency (75−88% yield). Significantly, this new aldol variant allows facile enantioselective access to a broad range of β-hydroxy aldehydes which are valuable intermediates in polyketide syntheses.
Stability analysis of numerical boundary conditions and implicit difference approximations for hyperbolic equations

Abstract Implicit noniterative finite-difference schemes have recently been developed by several authors for multidimensional systems of nonlinear hyperbolic partial differential equations. When applied to linear model equations with periodic boundary conditions those schemes are unconditionally stable (A-stable). As applied in practice the algorithms often face a severe time-step restriction. A major source of the difficulty is the treatment of the numerical boundary conditions. One conjecture has been that unconditional stability requires implicit numerical boundary conditions. An apparent counterexample was the space-time extrapolation considered by Gustafsson, Kreiss, and Sundstrom. In this paper we examine space (implicit) and space-time (explicit) extrapolation using normal mode analysis for a finite and infinite number of spatial mesh intervals. The results indicate that for unconditional stability with a finite number of spatial mesh intervals the numerical boundary conditions must be implicit.
Solar cycle variations in IMF intensity

Annual averages of logarithms of hourly interplanetary magnetic field intensities, obtained from geocentric spacecraft between November 1963 and December 1977, reveal the following solar cycle variation. For 2 to 3 years at each solar minimum period, the IMF intensity is depressed by 10-15 percent relative to its mean value realized during a broad nine-year period centered at solar maximum. No systematic variations occur during this nine-year period. The solar minimum decrease, although small relative to variations in some other solar wind parameters, is both statistically and physically significant.
Is fed policy still relevant for investors

Thirty-eight years of U.S. data indicate that U.S. monetary policy continues to have a strong relationship with security returns. U.S. stock returns are consistently higher and less volatile when the Federal Reserve is following an expansive monetary policy. Furthermore, the monetary policy–related return patterns of companies considered to be most sensitive to changes in monetary conditions are much more pronounced than average patterns. Finally, the influence of U.S. monetary policy is global; international indexes have return patterns similar to those for the U.S. market. Overall, the evidence suggests that investment professionals should continue to consider monetary conditions when performing fundamental analysis of U.S. and international securities.
The resultant of an unmixed bivariate system

This paper gives an explicit formula for computing the resultant of any sparse unmixed bivariate system with a given support. We construct square matrices whose determinant is exactly the resultant, with no extraneous factors. This is the first time that such matrices have been given for unmixed bivariate systems with arbitrary support. The matrices constructed are of hybrid Sylvester and Bezout type. The results extend previous work by the author by giving a complete combinatorial description of the matrix. We make use of the exterior algebra techniques of Eisenbud, Floystad, and Schreyer.
A Comparison of Conjoint Analysis Response Formats: Reply

(p. 452). This finding suggests that economists need to develop a better understanding of the decision rules that people use when answering these types of stated-preference response formats if statistical results are to effectively inform policy. McFadden (2001) argues that "the existence of underlying preferences is a vital scientific question for economists," and "the evidence on decision making from cognitive psychology implies only that economists must look through the smoke screen of rules to discern the deeper preferences that are needed to value economic policies" (p. 363). It is to this larger research agenda that the BHTR study aspired to contribute. Specifically, BHTR investigated convergent validity through a split-sample design where independent subsamples of survey participants were randomly assigned to answer either a rating, rank, or choice question. Responses to the rating and ranking questions were re-coded to choices. Models were then estimated with the
Correcting Grain-Errors in Magnetic Media

This paper studies new bounds and code constructions that are applicable to the combinatorial granular channel model previously introduced by Sharov and Roth. We derive new bounds on the maximum cardinality of a grain-error-correcting code and propose constructions of codes that correct grain-errors. We demonstrate that a permutation of the classical group codes (e.g., Constantin–Rao codes) can correct a single grain-error. In many cases of interest, our results improve upon the currently best known bounds and constructions. Some of the approaches adopted in the context of grain-errors may have application to related channel models.
Existence and Uniqueness Theorems for Massless Fields on a Class of Spacetimes with Closed Timelike Curves

We study the massless scalar field on asymptotically flat spacetimes with closed timelike curves (CTC’s), in which all future-directed CTC’s traverse one end of a handle (wormhole) and emerge from the other end at an earlier time. For a class of static geometries of this type, and for smooth initial data with all derivatives in L2 on ℐ−, we prove existence of smooth solutions which are regular at null and spatial infinity (have finite energy and finite L2-norm) and have the given initial data on ℐ−. A restricted uniqueness theorem is obtained, applying to solutions that fall off in time at any fixed spatial position. For a complementary class of spacetimes in which CTC’s are confined to a compact region, we show that when solutions exist they are unique in regions exterior to the CTC’s. (We believe that more stringent uniqueness theorems hold, and that the present limitations are our own.) An extension of these results to Maxwell fields and massless spinor fields is sketched. Finally, we discuss a conjecture whose meaning is essentially that the Cauchy problem for free fields is well defined in the presence of CTC’s whenever the problem is well-posed in a geometric-optics limit. We provide some evidence in support of this conjecture, and we present counterexamples that show that neither existence nor uniqueness is guaranteed under weaker conditions. In particular, both existence and uniqueness can fail in smooth, asymptotically flat spacetimes with a compact nonchronal region.
Desulfation and rearrangement of tigemonam to an isoxazolidin‐5‐one and the synthesis of the rearrangement product

The β-lactam antibiotic Tigemonam 2 undergoes desulfation to the N-hydroxyazetidinone 4, which rearranges to the isoxazolidin-5-one 6. The structure of the rearrangement product 6 was confirmed by synthesis.
GLAST Prospects for Swift-Era Afterglows

We calculate the GeV spectra of gamma-ray burst afterglows produced by inverse Compton scattering of these objects sub-MeV emission. We improve on earlier treatments by using refined afterglow parameters and new model developments motivated by recent Swift observations. We present time-dependent GeV spectra for standard, constant-parameter models, as well as for models with energy injection and with time-varying parameters, for a range of burst parameters. We evaluate the limiting redshift to which such afterglows can be detected by the GLAST Large Area Telescope, as well as by AGILE.
Local models of Shimura varieties and a conjecture of Kottwitz

We give a group theoretic definition of “local models” as sought after in the theory of Shimura varieties. These are projective schemes over the integers of a p-adic local field that are expected to model the singularities of integral models of Shimura varieties with parahoric level structure. Our local models are certain mixed characteristic degenerations of Grassmannian varieties; they are obtained by extending constructions of Beilinson, Drinfeld, Gaitsgory and the second-named author to mixed characteristics and to the case of general (tamely ramified) reductive groups. We study the singularities of local models and hence also of the corresponding integral models of Shimura varieties. In particular, we study the monodromy (inertia) action and show a commutativity property for the sheaves of nearby cycles. As a result, we prove a conjecture of Kottwitz which asserts that the semi-simple trace of Frobenius on the nearby cycles gives a function which is central in the parahoric Hecke algebra.