cssi/SciSciGPT-SciSciNet huggingface dataset:
Analytic determination of the pinhole collimator's point-spread function and RMS resolution with penetration

Pinhole collimators are widely used to image small organs and animals. The pinhole response function (PRF) of knife-edge pinhole collimators has been estimated previously using geometric constructions without considering penetration and using "roll-off" models that employ an exponential model for the flux. An analytic expression for the PRF on the imaging plane that includes the effect of aperture penetration is derived in this paper by calculating the flux for photons passing through the aperture and those passing through the attenuating material. The PRF is then used to approximate the angular-dependent root-mean-square resolution in the directions parallel and perpendicular to the tilt of the point source. The corresponding aspect ratio is then obtained. The formulas are then compared with experimental data.
Electron-beam quality degradation in a long undulator☆

Abstract Under the influence of space charge or longitudinal wake fields, transporting an electron beam through a long undulator can cause a degradation of beam quality. Using the PARMELA code, including longitudinal wake-field and space-charge contributions, we simulate a beam bunch that travels through the undulator. The electron beam is focused in both planes with the parabolic pole faces of the undulator. The effect of space charge on the beam envelope is also calculated using the K-V (Kapchinskij-Vladimirskij) envelope equation.
The Clinical Application of the Biopsychosocial Model

How physicians approach patients and the problems they present is much influenced by the conceptual models around which their knowledge is organized. In this paper the implications of the biopsychosocial model for the study and care of a patient with an acute myocardial infarction are presented and contrasted with approaches used by adherents of the more traditional biomedical model. A medical rather than psychiatric patient was selected to emphasize the unity of medicine and to help define the place of psychiatrists in the education of physicians of the future.
Affine Lie algebras and tame quivers

C.M. Ringel defined a Hall algebra associated with the category of representations of a quiver of Dynkin type and gave an explicit description of the structure constants of the corresponding Lie algebra. We utilize functorial properties of the Hall algebra to give a simple proof of the Ringel's result, and to generalize it to the case of a quiver of affine type. In particular a linear spanning set of the positive part of an affine Lie algebra and the corresponding structure constants are described in terms of quivers.
Price Scissors and the Structure of the Economy

This paper undertakes three sets of tasks: (i) it analyzes positive and normative aspects of price scissors (the domestic terms of trade between agriculture and industry) within nonsocialist as well as socialist LDCs. The critical role of the economy's institutional features (e.g., external trade environment, wage and income determination, and wage-productivity effects) is emphasized. Certain aspects of the Soviet Industrialization Debate and subsequent collectivization are interpreted, (ii) It develops simple rules to delineate who gains and who loses (within agriculture) from changes in terms of trade, (iii) It presents powerful (and informationally parsimonious) rules for Pareto-improving price reforms for cash crops and agricultural inputs.
The sphaleron rate: Bödeker's leading log

Bodeker has recently shown that the high temperature sphaleron rate, which measures baryon number violation in the hot standard model, receives logarithmic corrections to its leading parametric behavior; Γ=κ′[log(mD/g2T)+O(1)](g2T2/mD2)αW5T4. After discussing the physical origin of these corrections, I compute the leading log coefficient numerically: κ′=10.8±0.7. The log is fairly small relative to the O(1) “correction;” so non-logarithmic contributions dominate at realistic values of the coupling.
Adverbs and belief

Abstract The treatment of a certain class of adverbs in conceptual representation is given. Certain adverbs are shown to be representative of complex belief structures. These adverbs serve as pointers that explain where the sentence that they modify belongs in a belief structure.
INEX simulations of the optical performance of the AFEL

Abstract The AFEL (advanced free-electron laser) Project at Los Alamos National Laboratory is presently under construction. The project's goal is to produce a very high brightness electron beam which will be generated by a photocathode injector and a 20 MeV rf linac. Initial laser experiments will be performed with a 1 cm period permanent magnet wiggler which will generate intense optical radiation near a wavelength of 3.7 μm. Future experiments will operate with “slotted-tube” electromagnetic wigglers (formerly called “pulsed-wire” wigglers). Experiments at both fundamental and higher harmonic wavelengths are planned. This paper presents results of INEX (integrated numerical experiment) simulations of the optical performance of the AFEL. These simulations use the electron micropulse produced by the accelerator/beam transport code PARMELA in the 3-D FEL simulation code FELEX.
Entrepreneurial Dominance in Businesses Large and Small, Past and Present

Reiterating and broadening a theme broached by its author over a decade ago, this article seeks to redirect the attention of business historians to the central role of the individual entrepreneur in American economic history. In both giant corporations and small start-up firms, in the late twentieth century and the early nineteenth, it argues, the presence—or absence—of intelligent, organized, and creative entrepreneurs has determined the success or failure of companies much more clearly than has the nature of their organizational charts.
Novel 2-imidazoles as potent and selective α1A adrenoceptor partial agonists

Novel 2-imidazoles have been identified as potent partial agonists of the alpha(1A) adrenergic receptor, with good selectivity over the alpha(1B), alpha(1D) and alpha(2A) receptor sub-types. Sulfonamide 23 possessed attractive drug-like properties with respect to physicochemical and ADME properties and wide ligand selectivity.
[4 + 1] Cycloaddition of N-Heterocyclic Carbenes with Vinyl Isocyanates

[reaction: see text] N-Heterocyclic carbenes have been found to undergo [4 + 1] cycloaddition with various vinyl isocyanates to afford functionalized hydroindolone products.
Numerical Approximation to the Thermodynamic Integrals

We approximate boson thermodynamic integrals as polynomials in two variables chosen to give the correct limiting expansion and to smoothly interpolate into other regimes. With 10 free parameters, an accuracy of better than 0.009% is achieved for the pressure, internal energy density, and number density. We also revisit the fermion case, originally addressed by Eggleton, Faulkner, & Flannery (1973), and substantially improve the accuracy of their fits.
Nanostructure templating in inorganic solids with organic lyotropic liquid crystals

Various nanoscale semiconducting superlattices have been generated by direct templating in a lyotropic organic liquid crystal. These include superlattices of CdS, CdSe, and ZnS, templated in a liquid crystal formed by oligoethylene oxide oleyl ether amphiphiles and water. The semiconductor growth process copied the symmetry and characteristic dimensions of the original mesophase by avoiding growth of mineral within regularly spaced hydrophobic regions. The final product was a superlattice structure in which a mineral continuum was featured with hexagonally arranged cylindrical pores 2−3 nm in diameter and 5 nm apart. Most importantly, the superlattice morphology of the nanostructured systems in contact with the mesophase was found to be thermodynamically stable with respect to the solid lacking nanoscale features. We also found that both the morphology of features in the nanostructured solids and their dimension can be controlled through the amphiphile's molecular structure and water content in the liquid...
Synthesis, structure, electrical properties, and band structure calculations of TiAsTe.

The new compound TiAsTe has been synthesized by the reaction of the elements in a LiCl/KCl flux at 923 K. The compound crystallizes with four formula units in space group Immm of the orthorhombic s...
Synthesis and PTP1B Inhibition of Novel 4-Aryl-1-Oxa-9-Thiacyclopenta[b]fluorenes

Novel 4-aryl-1-oxa-9-thiacyclopenta[b]fluorenes were designed, synthesized, and evaluated as inhibitors of the protein tyrosine phosphatase, PTP1B. Compounds 3 (IC50 = 284 nM) and 4 (IC50 = 74 nM), showed nanomolar potency against PTP1B (TRDI(P)YETD(P)Y(P)YRK as substrate). Compound 4 also lowered insulin in the diabetic ob/ob mouse at a dose of 10 mg/kg/day, p.o.
Quantum Mechanical Analysis of the Equilateral Triangle Billiard: Periodic Orbit Theory and Wave Packet Revivals

Abstract Using the fact that the energy eigenstates of the equilateral triangle infinite well (or billiard) are available in closed form, we examine the connections between the energy eigenvalue spectrum and the classical closed paths in this geometry, using both periodic orbit theory and the short-term semi-classical behavior of wave packets. We also discuss wave packet revivals and show that there are exact revivals, for all wave packets, at times given by T rev =9μ a 2 /4 ħ π where a and μ are the length of one side and the mass of the point particle, respectively. We find additional cases of exact revivals with shorter revival times for zero-momentum wave packets initially located at special symmetry points inside the billiard. Finally, we discuss simple variations on the equilateral (60°–60°–60°) triangle, such as the half equilateral (30°–60°–90°) triangle and other “foldings,” which have related energy spectra and revival structures.
Extending Johnson's and Morita's homomorphisms to the mapping class group

We extend certain homomorphisms defined on the higher Torelli subgroups of the mapping class group to crossed homomorphisms defined on the entire mapping class group. In particular, for every k 2, we construct a crossed homomorphism k which extends Morita’s homomorphismz k to the entire mapping class group. From this crossed homomorphism we also obtain a crossed homomorphism extending the k th Johnson homomorphism k to the mapping class group. D Johnson and S Morita obtained their respective homomorphisms by considering the action of the mapping class group on the nilpotent truncations of the surface group; our approach is to mimic Morita’s construction topologically by using nilmanifolds associated to these truncations. This allows us to take the ranges of these crossed homomorphisms to be certain finite-dimensional real vector spaces associated to these nilmanifolds. 57N05; 57T15
Gromov-Witten theory, Hurwitz theory, and completed cycles

We establish an explicit equivalence between the stationary sector of the Gromov-Witten theory of a target curve X and the enumeration of Hurwitz coverings of X in the basis of completed cycles. The stationary sector is formed, by definition, by the descendents of the point class. Completed cycles arise naturally in the theory of shifted symmetric functions. Using this equivalence, we give a complete description of the stationary Gromov-Witten theory of the projective line and elliptic curve. Toda equations for the relative stationary theory of the projective line are derived.
An Infrared Camera for Leuschner Observatory and the Berkeley Undergraduate Astronomy Lab

ABSTRACT We describe the design, fabrication, and operation of an infrared camera which is in use at the 30 inch telescope of the Leuschner Observatory. The camera is based on a Rockwell PICNIC \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $256\times 256$ \end{document} pixel HgCdTe array, which is sensitive from 0.9 to 2.5 μm. The primary purpose of this telescope is for undergraduate instruction. The cost of the camera has been minimized by using commercial parts wherever practical. The camera optics are based on a modified O...
An electro-mechanically coupled 1-D polycrystalline model for piezoelectric stack actuators

Piezoelectric actuators used in nano-positioning devices exhibit highly non-linear behavior and strong hysteresis, which limits the efficiency of conventional non-model-based controllers. This paper presents a free energy model based on the theory of thermal activation for single crystal piezoceramics that couples mechanical stress and electric field. It is capable of predicting the hysteretic behavior along with the frequency-dependence present in these materials. The model is then coupled with a spring as a first step toward a 1-D model of a commercial nano-positioning stage and is the basis for future control applications. Quasi-static simulations are conducted to illustrate the effects of spring loading on the actuator behavior. A first step towards adapting the model for polycrystalline material is also presented. Simulations are shown to predict the rate-dependent strain response of a spring loaded polycrystalline stack actuator for various pre-stresses.
Multiple mirror manifolds and topology change in string theory

Abstract We use mirror symmetry to establish the first concrete arena of spacetime topology change in string theory. In particular, we establish that the quantum theories based on certain nonlinear sigma models with topologically distinct target spaces can be smoothly connected even though classically a physical singularity would be encountered. We accomplish this by rephrasing the description of these nonlinear sigma models in terms of their mirror manifold partners - a description in which the full quantum theory can be described exactly using lowest order geometrical methods. We establish that, for the known class of mirror manifolds, the moduli space of the corresponding conformal field theory requires not just two but numerous topologically distinct Calabi-Yau manifolds for its geometric interpretation. A single family of continously connected conformal theories thereby probes a host of topologically distinct geometrical spaces giving rise to multiple mirror manifolds .
A control systems model of privacy

Concerns about individual privacy, specifically in relation to automated data systems containing personal information, are considered in terms of a feedback control system model. This model provides a framework which appears to relate many separate concerns which individuals or groups have expressed about privacy. It also provides a framework which may be suitable for analyzing legislation or regulations promulgated for the protection of privacy. The model may assist in defining needed research on the need for privacy, or on the impact of inadequate protection of privacy.The model posits that data systems pose various "threats" to privacy depending on the extent and manner in which the existence of such information systems hinders the ability of individuals or groups to provide feedback to systems which affect them.
Failure by Fracture and Fatigue in “Nano” and “Bio” Materials

Author(s): Ritchie, R.O.; Muhlstein, C.L.; Nalla, R.K. | Abstract: The behavior of nanostructured materials/small-volume structures and biologi-cal/bio-implantable materials, so-called "nano" and "bio" materials, is currently much in vogue in materials science. One aspect of this field, which to date has received only limited attention, is their fracture and fatigue properties. In this paper, we examine two topics in this area, namely the premature fatigue failure of silicon-based micron-scale structures for microelectromechanical systems (MEMS), and the fracture properties of mineralized tissue, specifically human bone.
The Self-Energy of the Scalar Nucleon

The analogue of the variational principle was applied on the path integral to obtain the self-energy of the scalar nucleon interacting with the neutral scalar meson (with vanishing mass) field for variable coupling constant g[superscript 2]. To obtain the lowest energy of the nucleon from the asymptotic form of its kernel it is essential to replace it (t:time) by another variable [tau], say. Therefore it was first shown that the equation for a scalar nucleon in a given external field has the form which can be obtained from the Klein-Gordon equation by formally changing it by [tau]. It is known that the Klein-Gordon equation may be described, though indirectly, by Lagrangian form by introducing a fifth parameter u and a differential equation for a new function of the space-time variables and u. Then the kernel of this equation is represented by a path integral over trajectories in space time. To apply the variational technique on this kernel and find the best value of the lowest "energy" corresponding to the "Hamiltonian" of this equation, here again we need to replace i u by [sigma]. The kernel corresponding to the transition in which there are no mesons present initially and finally was obtained by integrating out the meson field in the kernel for the case of a given potential. The "energy" contains the logarithmic divergence which was cut off by the analogy to electrodynamics. The kernel of a nucleon for the same transition can be given in terms of the kernel just explained. From the asymptotic form of this kernel the best value of the lowest (or self-) energy M of the nucleon was obtained. M was given in terms of preliminarily renormalized mass m'. It was found that no solution exists for too large value of g[superscript 2]. For practical purposes the procedure to find the theoretical mass m in terms of M and g[superscript 2] was also explained.
Construction and Evaluation of a Metal Ion Biosensor

Escherichia coli, genetically engineered with a mercury (II)-sensitive promoter and the lux genes from Vibrio fischeri, were used as microbial bioluminescent sensors for the detection of mercury. Evaluation of this genetic construction was carried out by determining the effects of various parameters on cell suspensions maintained at constant conditions in a small 100-mL vessel. The strongest light intensities and quickest induction times occurred with cells in the midexponential growth phase maintained at 28C, concentrated to 1 [times] 10[sup 9] cells/mL, mixed at very fast speeds, and aerated at 2 vvm during light measurement in the small vessel. The cells were sensitive to the mercuric ion in the range of 20 nM to 4 [mu]M, and the total response time was on the order of 1 hour, depending on the above parameters. The cells exhibited great specificity for mercury. The cells had almost equal specificity for organic and inorganic forms of the mercuric ion and responded more weakly to the mercurous ion. A simple, inexpensive, durable miniature probe was constructed and operated using the optimum parameters found in the small vessel as a guide. The range of sensitivity to the mercuric ion detected in the probe was 10 nM to 4more » [mu]M when aeration was provided.« less
The clinical significance of simulation and modeling in leukemia chemotherapy

It seems certain that in the next thirty years---by the year 2001---the computer will become a major instrument in support of clinical practice. Part of our task today is to look beyond the frustrations, expense, and apparent waste of our present prototype systems and to distinguish the important themes which will bind medicine and computers together. In computer medicine we are clearly in the exploratory phase of a new technology---a position analogous to the early designers and users of automobiles. With the introduction of the automobile came a great variety of expensive, made-to-order cars which could only be run on poorly maintained muddy roads. To drive required a large measure of patience, enthusiasm, and self-reliance, coupled with a fine sense of the ridiculous. Moreover, the automobile scared the horses, and otherwise challenged the established order of things. And still it came, demanding new conventions to make its use effective: freeways, parking tickets, campers, bedroom communitites, air pollution---the good with the bad.
Sonic boom effects on beams loosely bound to their supports.

Potential damage to structural elements caused by sonic booms determined by considering effect of gap between beam and supports
Vortical and wave modes in 3D rotating stratified flows: random large-scale forcing

Utilizing an eigenfunction decomposition, we study the growth and spectra of energy in the vortical (geostrophic) and wave (ageostrophic) modes of a three-dimensional (3D) rotating stratified fluid as a function of e = f/N, where f is the Coriolis parameter and N is the Brunt–Vaisala frequency. Throughout, we employ a random large-scale forcing in a unit aspect ratio domain and set these parameters such that the Froude and Rossby numbers are roughly comparable and much less than unity. Working in regimes characterized by moderate Burger numbers, i.e. Bu = 1/e2 < 1 or Bu ≥ 1, our results indicate profound change in the character of vortical and wave mode interactions with respect to Bu = 1. Indeed, previous analytical work concerning the qualitatively different nature of these interactions has been in limiting conditions of rotation or stratification domination (i.e. when Bu ≪ 1 or Bu ≫ 1, respectively). As with the reference state of e = 1, for e < 1 the wave mode energy saturates quite quickly and the en...
Schottky-Barrier Carbon Nanotube Field-Effect Transistor Modeling

The theoretical performance of carbon nanotube field-effect transistors (CNFETs) with Schottky barriers (SBs) is examined by means of a general ballistic model. A novel approach is used to treat the SBs at the metal-nanotube contacts as mesoscopic scatterers by modifying the distribution functions for carriers in the channel. Noticeable current reduction is observed compared to previous ballistic models without SBs. Evanescent-mode analysis is used to derive a scale length and the potential profile near the contacts for radially symmetric CNFET structures. Band-to-band tunneling current and ambipolar conduction are also treated. The effects of different device geometries and different nanotube chiralities on the drain-current are studied using this simple model. Quantum conductance degradation due to SBs is also observed
IMPROVED VEHICLE PERFORMANCE USING COMBINED SUSPENSION AND BRAKING FORCES

SUMMARY This work presents a preliminary investigation into the integration of particular subsystems of an automobile's chassis. The specific focus of this research is the integration of Active Suspension components with Anti-Lock braking (ABS) mechanisms. The performance objective for the integrated approach is defined as a reduction in braking distance over just anti-lock brakes. Several models, of varying degrees of complexity, are presented to determine the effect of modeling accuracy on the potential performance improvement. In the most detailed model, a four degree of freedom Half Car vehicle model is developed along with models for a hydraulic Active Suspension and an ABS system. For both subsystems, actuator dynamics are included. The tire-road interface is modeled using the Magic Formula tire model. Individual controllers are developed for the subsystems and a governing algorithm is constructed to coordinate the two controllers. Simulations of the integrated controller and an ABS system, for each...
Amination of allylic alcohols in water at room temperature.

The “trick” to carrying out regiocontrolled aminations of allylic alcohols in water as the only medium is use of a nanomicelle’s interior as the organic reaction solvent. When HCO2Me is present, al...
Action of derived automorphisms on infinity-morphisms

In this paper we investigate how to simultaneously change homotopy algebras of a certain type and a corresponding infinity morphism between them, and show that this can be done in a homotopically unique way. More precisely, for a reduced cooperad $$\mathcal {C}$$ , given $${{{\mathrm{Cobar}}}}(\mathcal {C})$$ -algebras $$V$$ and $$W$$ and an $$\infty $$ -morphism $$U: V \leadsto W$$ , and for the automorphism $$\exp (D)$$ for any degree $$0$$ closed $$D \in {{\mathrm{Der}}}'({{{\mathrm{Cobar}}}}(\mathcal {C}))$$ , we produce new $${{{\mathrm{Cobar}}}}(\mathcal {C})$$ -algebras and a new $$\infty $$ -morphism $$\widetilde{U} : V^D \leadsto W^D$$ extending $$U$$ in a universal way. Operads play the central role in answering this question, in particular a $$2$$ -colored operad $${{\mathrm{Cyl}}}(\mathcal {C})$$ that governs pairs of $$\infty $$ -algebras and $$\infty $$ -morphisms between them.
EVIDENCE FOR SOLAR FREQUENCY DEPENDENCE ON SUNSPOT TYPE

High-degree solar mode frequencies as measured by ring diagrams are known to change in the presence of the strong magnetic fields found in active regions. We examine these changes in frequency for a large sample of active regions analyzed with data from the Michelson Doppler Imager on board the Solar and Heliospheric Observatory spacecraft, spanning most of solar cycle 23. We confirm that the frequencies increase with increasing magnetic field strength, and that this dependence is generally linear. We find that the dependence is slightly but significantly different for active regions with different sunspot types.
Entanglement and Open Systems in Algebraic Quantum Field Theory

Abstract Entanglement has long been the subject of discussion by philosophers of quantum theory, and has recently come to play an essential role for physicists in their development of quantum information theory. In this paper we show how the formalism of algebraic quantum field theory (AQFT) provides a rigorous framework within which to analyse entanglement in the context of a fully relativistic formulation of quantum theory. What emerges from the analysis are new practical and theoretical limitations on an experimenter's ability to perform operations on a field in one spacetime region that can disentangle its state from the state of the field in other spacelike-separated regions. These limitations show just how deeply entrenched entanglement is in relativistic quantum field theory, and yield a fresh perspective on the ways in which the theory differs conceptually from both standard non-relativistic quantum theory and classical relativistic field theory.
Chiral copper (ii) complexes as Lewis acids for catalyzed cycloaddition, carbonyl addition, and conjugate addition reactions

Bis(oxazoline) copper(II) complexes 1-3 function as enantioselective Lewis acid catalysts for carbocyclic and hetero Diels-Alder, aldol, Michael, ene, and amination reactions with substrates capable of chelation. X-ray crystallography of the catalyst reveals a propensity for the formation of distorted square planar or square pyramidal complexes. The sense of asymmetric induction is identical for all the processes catalyzed by (Cu((S,S)-t-Bu-box))(X)2 complexes 1 and 2 resulting from the intervention of a distorted square planar catalyst- substrate binary complex.
Synchrony, complexity and directiveness in mothers’ interactions with infants pre- and post-cochlear implantation ☆

Abstract This study investigated effects of profound hearing loss on mother–infant interactions before and after cochlear implantation with a focus on maternal synchrony, complexity, and directiveness. Participants included two groups of mother–infant dyads: 9 dyads of mothers and infants with normal hearing; and 9 dyads of hearing mothers and infants with profound hearing loss. Dyads were observed at two time points: Time 1, scheduled to occur before cochlear implantation for infants with profound hearing loss (mean age = 13.6 months); and Time 2 (mean age = 23.3 months), scheduled to occur approximately six months after cochlear implantation. Hearing infants were age-matched to infants with hearing loss at both time points. Dependent variables included the proportion of maternal utterances that overlapped infant vocalizations, maternal mean length of utterance, infant word use, and combined maternal directives and prohibitions. Results showed mothers’ utterances overlapped the vocalizations of infants with hearing loss more often before cochlear implantation than after, mothers used less complex utterances with infants with cochlear implants compared to hearing peers (Time 2), and mothers of infants with profound hearing loss used frequent directives and prohibitions both before and after cochlear implantation. Together, mothers and infants adapted relatively quickly to infants’ access to cochlear implants, showing improved interactional synchrony, increased infant word use, and levels of maternal language complexity compatible with infants’ word use, all within seven months of cochlear implant activation.
MANTLE CONVECTION, PLATE TECTONICS, AND VOLCANISM ON HOT EXO-EARTHS

Recently discovered exoplanets on close-in orbits should have surface temperatures of hundreds to thousands of Kelvin. They are likely tidally locked and synchronously rotating around their parent stars and, if an atmosphere is absent, have surface temperature contrasts of many hundreds to thousands of Kelvin between permanent day and night sides. We investigated the effect of elevated surface temperature and strong surface temperature contrasts for Earth-mass planets on the (1) pattern of mantle convection, (2) tectonic regime, and (3) rate and distribution of partial melting, using numerical simulations of mantle convection with a composite viscous/pseudo-plastic rheology. Our simulations indicate that if a close-in rocky exoplanet lacks an atmosphere to redistribute heat, a 400 K surface temperature contrast can maintain an asymmetric degree 1 pattern of mantle convection in which the surface of the planet moves preferentially toward subduction zones on the cold night side. The planetary surface features a hemispheric dichotomy, with plate-like tectonics on the night side and a continuously evolving mobile lid on the day side with diffuse surface deformation and vigorous volcanism. If volcanic outgassing establishes an atmosphere and redistributes heat, plate tectonics is globally replaced by diffuse surface deformation and volcanism accelerates and becomes distributed more uniformly across the planetary surface.
QUANTITATIVE ANALYSIS OF RESPONSES FROM LATERAL-LINE NERVES OF FISHES. II

1. The lateral-line nerves of trout as well as those of catfish are found to discharge impulses spontaneously at a high frequency. 2. The frequency of nerve impulse discharge is measured as a function of the number of participating receptor groups (lateral-line sense organs). A quantitative analysis is made of the contribution to the total response made by each group of sense organs. 3. An analysis of the variability of the response is presented which makes it possible to estimate quantitatively the longitudinal extent of damage to the neuromasts due to surgical manipulation. 4. A method is described for recording the response of a single nerve fiber in the lateral-line trunk. 5. The frequency of the spontaneous discharge from the lateral-line nerve trunk when plotted as a function of temperature according to the Arrhenius equation yields a temperature characteristic of approximately 5000 calories. 6. The variability of the frequency of response as a function of temperature indicates the existence of temperature thresholds for the spontaneous activity of the neuromasts. 7. A possible basis for the spontaneous activity is considered. It is pointed out that the lateral-line system may serve as a model of the Purkinje cells of the cerebellum.
Identifying the Effects of Unjustified Confidence versus Overconfidence: Lessons Learned from Two Analytic Methods

One of the most common findings in behavioral decision research is that people have unrealistic beliefs about how much they know. However, demonstrating that misplaced confidence exists does not necessarily mean that there are costs to it. This paper contrasts two approaches toward answering whether misplaced confidence is good or bad, which we have labeled the overconfidence and unjustified confidence approach. We first consider conceptual and analytic issues distinguishing these approaches. Then, we provide findings from a set of simulations designed to determine when the approaches produce different conclusions across a range of possible confidence�knowledge�outcome relationships. Finally, we illustrate the main findings from the simulations with three empirical examples drawn from our own data. We conclude that the unjustified confidence approach is typically the preferred approach, both because it is appropriate for testing a larger set of psychological mechanisms as well as for methodological reasons.
1-(Alkyl/arylthiocarbamoyl)benzotriazoles as stable isothiocyanate equivalents: synthesis of Di- and trisubstituted thioureas.

1-(Alkyl/arylthiocarbamoyl)benzotriazoles 4a−i were synthesized in yields of 91−99% from bis(benzotriazolyl)methanethione (3). Reagents 4a−g were then used as isothiocyanate equivalents for the efficient synthesis of 10 secondary and 14 tertiary thioureas in high-yielding, convenient processes.
Computing the distance to an uncontrollable system

Algorithms for computing the distance from a particular controllable system to the closest uncontrollable system are presented. The authors give an interpretation of the problem and propose solutions in the form of several linearly convergent iterative algorithms. The algorithms are presented for the real and complex perturbation problems, i.e. when the real system under investigation is subject to either real or complex perturbations. >
An Empirical Assessment of Endogeneity Issues in Demand Analysis for Differentiated Products

This article explores the issue of price and expenditure endogeneity in empirical demand analysis. The analysis focuses on the U.S. carbonated soft drink market. We test the null hypothesis that price and expenditures are exogenous in the demand for carbonated soft drinks. Using an almost ideal demand system (AIDS) specification, we strongly reject exogeneity for both prices and expenditures. We find that accounting for price/expenditures endogeneity significantly impacts demand elasticity estimates. We also evaluate the implications of endogeneity issues for testing weak separability. Over the last few decades, strong linkages between economic theory and econometric methods have stimulated much empirical analysis of consumer behavior (e.g., Deaton and Muellbauer 1980b). The basic approach involves estimating Marshallian demand functions, expressing quantities consumed as functions of prices and household expenditures. The usual practice is to treat prices and expenditure as exogenous variables. In this article, we question the validity of these exogeneity assumptions, especially when focusing on the demand for differentiated products. 1 This is particularly important to the extent that food consumption typically involves differentiated products in market economies. We also examine the interactions between endogeneity of prices/expenditure in demand systems and the testing for weak separability of consumer preferences.
Modeling C-based embedded system using UML design

Unified Modeling Language (UML) 2.0 is emerging in the area of modeling the design of embedded system. The most common implementation for the embedded-system models has been C++. On one hand, the most common programming language for embedded system overall by far is the functional language C. On the other hand, the UML is used almost exclusively for object-oriented systems development. This paper present an approach of applying UML in the functionally-oriented embedded systems design. This approach is illustrated using a stopwatch design example.
Stability analysis for linear systems under State constraints

This note revisits the problem of stability analysis for linear systems under state constraints. New and less conservative sufficient conditions are identified under which such systems are globally asymptotically stable. Based on these sufficient conditions, iterative linear matrix inequality (LMI) algorithms are proposed for testing global asymptotic stability of the system. In addition, these iterative LMI algorithms can be adapted for the design of globally stabilizing state feedback gains.
Quasisymmetric (k; l)-hook Schur functions

We introduce a quasisymmetric generalization of Berele and Regev’s hook Schur functions and prove that these new quasisymmetric hook Schur functions decompose the hook Schur functions in a natural way. We examine the combinatorics of the quasisymmetric hook Schur functions, providing a relationship to Gessel’s fundamental quasisymmetric functions and an analogue of the Robinson-Schensted-Knuth algorithm. We also prove that the multiplication of quasisymmetric hook Schur functions with hook Schur functions behaves the same as the multiplication of quasisymmetric Schur functions with Schur functions.
The Children’s Health Insurance Program: Expanding the Framework to Evaluate State Goals and Performance

A comprehensive framework was devised to evaluate the State Children’s Health Insurance Program (SCHIP) established in 1997. The framework relies on a number of potential measures and data sources for reviewing the program information recorded by states in SCHIP applications, particularly their strategic objectives and proposed performance measures. The analysis reveals that the states propose a wide range of objectives and measures and that there is considerable variation among the states. Overall, states’ SCHIP plans tend to stress program enrollment and access to services but fail to emphasize the type and quality of services children receive once they are enrolled in the program. A broader conceptual framework is needed for policy makers, advocates, and researchers to make a full assessment of state goals and SCHIP performance.
An empirical Bayes model for gene expression and methylation profiles in antiestrogen resistant breast cancer

Background The nuclear transcription factor estrogen receptor alpha (ER-alpha) is the target of several antiestrogen therapeutic agents for breast cancer. However, many ER-alpha positive patients do not respond to these treatments from the beginning, or stop responding after being treated for a period of time. Because of the association of gene transcription alteration and drug resistance and the emerging evidence on the role of DNA methylation on transcription regulation, understanding of these relationships can facilitate development of approaches to re-sensitize breast cancer cells to treatment by restoring DNA methylation patterns.
Decahydroquinoline construction through aza-annulation: A stereoselective synthesis of (±)-5-epipumiliotoxin C.

Abstract Aza-annulation of activated acrylic acid derivatives with 3-benzylamino-2-cyclohexenone led to the efficient formation of the corresponding bicyclic lactam. Stereospecific hydrogenation of this unsaturated lactam resulted in the selective formation of the cis fused bicyclic alkaloid, and subsequent elaboration at C-5 and C-2 completed the synthesis of the decahydroquinoline alkaloid (±)-5-epipumiliotoxin C.
Rank-Based Estimation for Autoregressive Moving Average Time Series Models

. We establish asymptotic normality and consistency for rank-based estimators of autoregressive-moving average model parameters. The estimators are obtained by minimizing a rank-based residual dispersion function similar to the one given by L.A. Jaeckel [Ann. Math. Stat. Vol. 43 (1972) 1449–1458]. These estimators can have the same asymptotic efficiency as maximum likelihood estimators and are robust. The quality of the asymptotic approximations for finite samples is studied via simulation.
Finite-dimensional direct adaptive control for discrete-time infinite-dimensional linear systems

Abstract Adaptive model tracking of a finite-dimensional model by an infinite-dimensional linear, discrete-time system is shown to be possible. Relationships between the Kalman-Yacubovic equations for discrete-time and strictly positive real transfer functions are proved and a Lyapunov stability analysis is carried out to show convergent output tracking occurs.
The Columbian Exchange: A History of Disease, Food, and Ideas

This paper provides an overview of the long-term impacts of the Columbian Exchange -- that is, the exchange of diseases, ideas, food crops, technologies, populations, and cultures between the New World and the Old World after Christopher Columbus' voyage to the Americas in 1492. We focus on the aspects of the exchange that have been most neglected by economic studies; namely the transfer of diseases, food crops, and knowledge between the two Worlds. We pay particular attention to the effects of the exchange on the Old World.
Catalytic C–H oxidation by a triazamacrocyclic ruthenium complex

A method for oxygenation of tertiary and benzylic C–H bonds is described that uses 1–10 mol% (1,4,7-trimethyl-1,4,7-triazacyclo-nonane)ruthenium(III) trichloride as catalyst and ceric (IV) ammonium nitrate (CAN) as the terminal oxidant. The reaction is conveniently performed in aqueous solvent mixtures on substrates bearing a number of common, polar functional groups. The scope and efficiency of this process are comparable or superior to other known catalytic C–H oxidation technologies. Chemoselectivity trends and kinetic isotope effect data implicate a stepwise, radical-rebound mechanism for this transformation.
Constrained parameter estimation with applications to blending operations

Abstract The classical least squares approach to parameter estimation for dynamic models ignores a priori information about the feasible values of the estimated parameters. But in many practical problems, such information is available in the form of upper and lower limits. In this paper, two alternative techniques are evaluated for this important class of constrained parameter estimation problems for dynamic systems. Simulation results for two blending problems illustrate that more accurate parameter estimates and better predictions can be obtained by using a quadratic programming approach.
Connections in acyclic hypergraphs

Abstract We demonstrate a sense in which the equivalence between blocks (subgraphs without articulation points) and biconnected components (subgraphs in which there are two edge-disjoint paths between any pair of nodes) that holds in ordinary graph theory can be generalized to hypergraphs. The result has an interpretation for relational databases that the universal relations described by acyclic join dependencies are exactly those for which the connections among attributes are defined uniquely. We also exhibit a relationship between the process of Graham reduction (Graham, 1979) of hypergraphs and the process of tableau reduction (Aho, Sagiv and Ullman, 1979) that holds only for acyclic hypergraphs.
Properties of time‐series estimates of degree of leverage measures

Empirical studies suggest that time-series regression estimates of the degrees of operating and financial leverage have a tendency to produce measures less than one. According to ex ante theory, these measures should be greater than one for firms operating above the breakeven point. There have also been suggestions that the biases in these estimates may be attributable to an underlying increase in unit sales. This work presents evidence that these counter-intuitive measures are produced by changes in the firm's operating parameters (unit price, variable cost, fixed cost and interest payments). It further suggests that attempts to control for the underlying change in unit sales substantially increase the volatility of predicted estimates.
MIMO-OFDM Beamforming for Improved Channel Estimation

The MIMO-OFDM beamforming design problem is addressed from a system level standpoint. A beamforming method is proposed which helps improve the receiver channel estimation performance without degrading any benefit of a conventional beamformer. To that end, the smoothed singular value decomposition (SSVD) algorithm is first developed to get "close" effective channels after beamforming for two adjacent subcarriers. Based on the SSVD algorithm, the frequency smoothed beamformer (FSB) design is then derived, in which smooth effective channels across all subcarriers are generated and thus the receiver can apply interpolation and smoothing to improve the channel estimation performance. The close singular value problem is discussed. Statistical characteristics of the effective channel are analyzed, which is used to design channel estimation for the beamformed channel. Simulation results show that the FSB design is efficient in the IEEE 802.11n setting.
Modern Tests of Lorentz Invariance

Motivated by ideas about quantum gravity, a tremendous amount of effort over the past decade has gone into testing Lorentz invariance in various regimes. This review summarizes both the theoretical frameworks for tests of Lorentz invariance and experimental advances that have made new high precision tests possible. The current constraints on Lorentz violating effects from both terrestrial experiments and astrophysical observations are presented.
RF Distribution optimization in the main linacs of the ILC

The nominal design gradient in the main linacs of the International Linear Collider (ILC) is 31.5 MV/m for a beam current of 9.0 mA. However, the superconducting cavities built to date have demonstrated a range in sustainable gradient extending well below this goal, being limited by Q drop-off and quenching. For the current distribution of gradient limits in the RF cavities of the ILC linacs we have optimized the overall gradient of a 26 cavity RF unit, assuming the availability of various combinations of circulators and variable power tap-offs. One simple way of running such a unit is to set RF power, beam arrival time, and all loaded Q values so that the power is matched and the gradient in all cavities equals the gradient limit in the poorest performing cavity. One improvement strategy is to adjust the cavity couplings individually (possible, since circulators are assumed in the baseline ILC design) or in pairs (when circulators are not needed) using the movable antennae of the fundamental mode couplers. Another strategy is to use variable power tap-offs (VTOs) by which the RF power to succeeding pairs of cavities can be made to differ.
Feature Selection Using Regularization in Approximate Linear Programs for Markov Decision Processes

Approximate dynamic programming has been used successfully in a large variety of domains, but it relies on a small set of provided approximation features to calculate solutions reliably. Large and rich sets of features can cause existing algorithms to overfit because of a limited number of samples. We address this shortcoming using L1 regularization in approximate linear programming. Because the proposed method can automatically select the appropriate richness of features, its performance does not degrade with an increasing number of features. These results rely on new and stronger sampling bounds for regularized approximate linear programs. We also propose a computationally efficient homotopy method. The empirical evaluation of the approach shows that the proposed method performs well on simple MDPs and standard benchmark problems.