cssi/SciSciGPT-SciSciNet huggingface dataset:
Epitaxial Growth of Magnetic Nickel Nanodots by Pulsed Laser Deposition

Epitaxial nickel magnetic nanodots were obtained by pulsed laser deposition (PLD) technique on Si (100) substrate using epitaxial TiN film as the template. Characterization methods include: high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM) Z-contrast imaging, selected area electron diffraction (SAD), and X-ray diffraction (XRD) techniques. The results showed that as long as no coalescence between neighboring dots occurred, the dots are all single crystal. The predominant orientation relationship observed is Ni (100) // TiN (100) // Si (100), the so-called “cube-on-cube” orientation relationship. Other rotational orientation relationships, where the nickel crystal rotates an angle with respect to TiN (011) directions, were also observed. The dots are in faceted island shapes, bounded by (111) and (001) facets. The actual size of dots varies from a few nanometers to tens of nanometers, depending on the deposition time and temperature. The shape of a certain dot was found to be closely related to its epitaxial orientation. Effects of deposition temperature and template crystalline quality were studied. It was found that deposition temperature in a certain range does not have much influence on the epitaxial orientation of dots, while the crystalline quality of titanium nitride (the underlying template) is primarily responsible for the orientation variation. At the optimum condition, samples with a large fraction of cube-on-cube orientated nickel dots could be obtained in a rather wide temperature range (up to 250 °C), as evidenced by the strong reflections from both SAD and XRD. Samples containing more than one layer of nickel and titanium nitride matrix were also studied. The results showed that the degree of orientation perfection could be greatly improved by decreasing the size of dots.
Consumer and Market Responses to Mad Cow Disease

We examine how consumers and financial markets in the United States react to two health warnings about mad cow disease: the first discovery of an infected cow in December 2003 and an Oprah Winfrey show on the potentially harmful effects that aired seven years earlier. Using a unique product-level scanner data set of a national grocery chain, we find a pronounced and significant reduction in beef sales following the first discovered infection, which dissipates slowly over the next three months. Cattle futures show a comparable pattern of abnormal price drops to the scanner data. Contracts with longer maturity show smaller drops, suggesting that the market anticipated the impact to be transitory. Cattle futures show abnormal price drops after the Oprah Winfrey show that are more than 50% of the drop following the 2003 discovery of an infected cow.
A passivity-based stability criterion for a class of interconnected systems and applications to biochemical reaction networks

We present a stability test for a class of interconnected nonlinear systems motivated by biochemical reaction networks. The main result determines global asymptotic stability of the network from the diagonal stability of a "dissipativity matrix" which incorporates information about the passivity properties of the subsystems, the interconnection structure of the network, and the signs of the interconnection terms. This stability test encompasses the "secant criterion" for cyclic networks presented in [Arcak, M., et al., 2006], and extends it to a general interconnection structure represented by a graph. The new stability test is illustrated on a mitogen activated protein kinase (MAPK) cascade model, and on a branched interconnection structure motivated by metabolic networks.
Rearranging The Bicyclo[3.1.0]Hexane Template Of Carbocyclic Nucleosides To Improve Binding Recognition By Kinases

A novel bicyclo[3.1.0]hexane carbocyclic nucleoside (4) with a south-like conformation amenable to interact with the herpes thymidine kinase (HSV-tk) was synthesized with an endo-hydroxyl group positioned at the tip of the bicyclo[3.1.0]hexane ring system opposite to the tip of the fused cyclopropane ring. The introduction of the hydroxymethyl chain through a Baylis-Hillman type reaction and the regioselective opening of a cyclic sulfite intermediate to introduce the nitrogen functionality at the correct position are highlighted.
Domain wall holography for finite temperature scaling solutions

We investigate a class of near-extremal solutions of Einstein-Maxwell-scalar theory with electric charge and power law scaling, dual to charged IR phases of relativistic field theories at low temperature. These are exact solutions of theories with domain wall vacua; hence, we use nonconformal holography to relate the bulk and boundary theories. We numerically construct a global interpolating solution between the IR charged solutions and the UV domain wall vacua for arbitrary physical choices of Lagrangian parameters. By passing to a conformal frame in which the domain wall metric becomes that of AdS, we uncover a generalized scale invariance of the IR scaling solution, indicating a connection to the physics of Lifshitz fixed points. Finally, guided by effective field theoretic principles and the physics of nonconformal D-branes, we argue for the applicability of domain wall holography even in theories with AdS critical points, namely those theories for which a scalar potential is dominated by a single exponential term over a large range.
Optical Components For The SHIVA Laser

In addition to its other characteristics, the Nova Laser Fusion facility may well be the largest precision optical project ever undertaken. Moreover, during the course of construction, concurrent research and development has been successfully conducted, and has resulted in significant advances in various technical areas, including manufacturing efficiency. Although assembly of the first two beams of Nova is just commencing, the optical production, including construction of the special facilities required for many of the components, has been underway for over three years, and many phases of the optical manufacturing program for the first 10 beams will be completed within the next two years. On the other hand, new requirements for second and third harmonic generation have created the need to initiate new research and development. This work has been accomplished through the enormous cooperation DOE/LLNL has received from commercial industry on this project. In many cases, industry, where much of the optical component research and development and virtually all of the manufacturing is being done, has made substantial investment of its own funds in facilities, equipment, and research and development, in addition to those supplied by DOE/LLNL.
Estimated grain saltation in a Martian atmosphere

Mariner 9 spacecraft images showing evidence of variable surface features and surface erosion resulting from atmospheric wind on Mars have caused a renewed interest in the eolian mechanics of saltating grains. To study this phenomenon, both experimental investigation in an atmospheric wind tunnel and numerical solutions of the equations of motion of a single grain under Martian surface conditions were conducted. The numerical solutions for earth were used and empirically adjusted to correlate with existing experimental data for Mars. These modified equations were then solved to estimate grain motion for Mars. These calculations show the importance of a lifting force on the grain to initiate motion in both earth and Mars calculations. Major findings include a comparison of earth and Mars grain trajectories that show Mars length scales to be longer and to fall with a higher terminal grain velocity. The grains in the Mars calculation also made a smaller collision angle with the surface on rebound.
Modeling Heteroskedasticity of Crop Yield Distributions: Implications for Normality

The paper analyzes the extent to which ignorance of heteroskedasticity or its inadequate modeling would result in misleading statistical inferences about crop yield distribution. We follow the "detrending mean yield approach" in which we model the conditional mean yield using a panel data model. We assume alternative structures of variance-covariance matrix for the random component. Heteroskedasticity robust and non-robust estimation methods are used before performing a joint normality test on the random component of crop yield data. Our findings provide evidence against the claim that virtually all previous findings of non-normality in crop yields are infected because of the ignorance of heteroskedasticity or its inappropriate modeling. Accounting for heteroskedasticity in crop yield data would matter for validity of evidence against normality only to the extent that its proportion among the source of departure from normal distribution is relatively sizable.
CAUSES OF RETAIL PRICE FIXITY: AN EMPIRICAL ANALYSIS

Abstract There are many plausible theoretical explanations for retail price fixity, but few empirical tests. This study develops a general theoretical model that nests several explanations within a real options framework. One unique implication of this model is that retail prices will exhibit greater fixity the more volatile are wholesale prices. Our empirical example supports the real options hypothesis as well as price rivalry, flat marginal cost curves, and consumer search or goodwill costs.
Planning graph as a (dynamic) CSP: exploiting EBL, DDB and other CSP search techniques in Graphplan

This paper reviews the connections between Graphplan's planning-graph and the dynamic constraint satisfaction problem and motivates the need for adapting CSP search techniques to the Graphplan algorithm. It then describes how explanation based learning, dependency directed backtracking, dynamic variable ordering, forward checking, sticky values and random-restart search strategies can be adapted to Graphplan. Empirical results are provided to demonstrate that these augmentations improve Graphplan's performance significantly (up to 1000x speedups) on several benchmark problems. Special attention is paid to the explanation-based learning and dependency directed backtracking techniques as they are empirically found to be most useful in improving the performance of Graphplan.
Variations in North American Summer Precipitation Driven by the Atlantic Multidecadal Oscillation

Understanding the development and variation of the atmospheric circulation regimes driven by the Atlantic multidecadaloscillation(AMO)isessentialbecausethesecirculationsinteractwithotherforcingsondecadaland interannual time scales. Collectively, they determine the summer (June, July, and August) precipitation variations for North America. In this study, a general circulation model (GCM) is used to obtain such understanding, with a focus on physical processes connecting the AMO and the summertime precipitation regime change in NorthAmerica.Twoexperimentalrunsareconductedwithseasurfacetemperature(SST)anomaliesimposedin the North Atlantic Ocean that represent the warm and cold phases of the AMO. Climatological SSTs are used elsewhere in the oceans. Model results yield summertime precipitation anomalies in North America closely matching the observed anomaly patterns in North America, suggesting that the AMO provides a fundamental control on summertime precipitation in North America at decadal time scales. The impacts of the AMO are achieved by a chain of events arising from different circulation anomalies during warm and cold phases of the AMO. During the warm phase, the North Atlantic subtropical high pressure system (NASH) weakens, and the North American continent is much less influenced by it. A massive body of warm air develops over the heated land in North America from June‐August, associated with high temperature and low pressure anomalies in the lowertroposphereandhighpressureanomaliesintheuppertroposphere.Incontrast,duringthecoldphaseofthe AMO, the North American continent, particularly to the west, is much more influenced by an enhanced NASH. Cooler temperatures and high pressure anomalies prevail in the lower troposphere, and a frontal zone forms in the upper troposphere. These different circulation anomalies further induce a three-cell circulation anomaly pattern over North America in the warm and cold phases of the AMO. In particular, during the cold phase, the three-cell circulation anomaly pattern features a broad region of anomalous low-level southerly flow from the Gulf of Mexico into the U.S. Great Plains. Superimposed with an upper-troposphere front, more frequent summertime storms develop and excess precipitation occurs over most of North America. A nearly reversed condition occurs during the warm phase of the AMO, yielding drier conditions in North America. This new understandingprovides a foundation for further studyand better prediction of the variations of North American summer precipitation, especially when modulated by other multidecadal variations—for example, the Pacific decadal oscillation and interannual variations associated with the ENSO and the Arctic Oscillation.
Fiber-optic bus-oriented single-hop interconnections among multi-transceiver stations

The single-path selective-broadcast interconnection (SBI) is a static, passive interconnection among a set of stations, each equipped with multiple c transmitters and receivers. It uses c/sup 2/ buses, each interconnecting a subset of the stations, and provides a single common bus to any two stations. The author explores those merits of this SBI which are related directly to its implementation in fiber optics. When compared with c buses, each interconnecting all stations, the SBI is shown to offer substantial advantages in power budget and the maximum number of stations that can be interconnected without repeaters or amplifiers. It is also attractive in terms of the required passive fiber optic components such as fiber segments and star couplers. For a fixed power budget and direct detection, the capacity of this SBI is shown to be highest among bus-oriented single-hop interconnections for both a uniform traffic pattern and the worst-case unknown skew. >
Semiconjugacies to angle-doubling

A simple consequence of a theorem of Franks says that whenever a continuous map, g, is homotopic to angle-doubling on the circle, it is semi-conjugate to it. We show that when this semiconjugacy has one disconnected point inverse, then the typical point in the circle has a point inverse with uncountably many connected components. Further, in this case the topological entropy of g is strictly larger than that of angle-doubling, and the semiconjugacy has unbounded variation. An analogous theorem holds for degree-D circle maps with D > 2.
State-to-State Spectroscopy and Dynamics of Ions and Neutrals by Photoionization and Photoelectron Methods

Recent advances in high-resolution photoionization, photoelectron, and photodissociation studies based on single-photon vacuum ultraviolet (VUV) and two-color infrared (IR)-VUV, visible (Vis)-ultraviolet (UV), and VUVVUV laser excitations are illustrated with selected examples. VUV laser photoionization coupled with velocity-map-imaging threshold photoelectron (VMI-TPE) detection can achieve comparable energy resolution but has higher-detection sensitivities than those observed in VUV laser pulsed field ionization photoelectron (PFI-PE) measurements. For molecules with known intermediate states, IR-VUV and Vis-UV excitation schemes are highly sensitive for rovibronically selected and resolved PFI-PE studies. The successful applications of the VUV-PFI-PE, VUV-VMI-TPE, and Vis-UVPFI-PE methods to state-resolved and state-to-state photoelectron studies of transient radicals and transitional metal–containing molecules are highlighted. The most recently established VUV-VUV pump-probe time-slice VMI photoion method is shown to be promising for state-to-state photodissociation studies of small molecules relevant to planetary atmospheres and for the fundamental understanding of photodissociation dynamics.
Latent Collaborative Retrieval

Retrieval tasks typically require a ranking of items given a query. Collaborative filtering tasks, on the other hand, learn to model user's preferences over items. In this paper we study the joint problem of recommending items to a user with respect to a given query, which is a surprisingly common task. This setup differs from the standard collaborative filtering one in that we are given a query × user × item tensor for training instead of the more traditional user × item matrix. Compared to document retrieval we do have a query, but we may or may not have content features (we will consider both cases) and we can also take account of the user's profile. We introduce a factorized model for this new task that optimizes the top-ranked items returned for the given query and user. We report empirical results where it outperforms several baselines.
TESTING BLEND SCENARIOS FOR EXTRASOLAR TRANSITING PLANET CANDIDATES. I. OGLE-TR-33: A FALSE POSITIVE

We report high-resolution spectroscopic follow-up observations of the faint transiting planet candidate OGLE-TR-33 (V = 14.7), located in the direction of the Galactic center. Small changes in the radial velocity of the star were detected that initially suggested the presence of a large planet or brown dwarf in orbit. However, further analysis revealed spectral line asymmetries that change in phase with the 1.95 day period, casting doubt on those measurements. These asymmetries make it more likely that the transit-like events in the light curve are the result of contamination from the light of an eclipsing binary along the same line of sight (referred to as a blend). We performed detailed simulations in which we generated synthetic light curves resulting from such blend scenarios and fitted them to the measured light curve. Guided by these fits and the inferred properties of the stars, we uncovered a second set of lines in our spectra that correspond to the primary of the eclipsing binary and explain the asymmetries. Using all the constraints from spectroscopy, we were then able to construct a model that satisfies all the observations and to characterize the three stars based on model isochrones. OGLE-TR-33 is fully consistent with being a hierarchical triple system composed of a slightly evolved F6 star (the brighter object) near the end of its main-sequence phase and an eclipsing binary with a K7-M0 star orbiting an F4 star. The application to OGLE-TR-33 of the formalism developed to fit light curves of transit candidates illustrates the power of such simulations for predicting additional properties of the blend and for guiding further observations that may serve to confirm that scenario, thereby ruling out a planet. Tests such as this can be very important for validating faint candidates.
Animal Spirits, Financial Crises and Persistent Unemployment

This article uses a rational expectations model with multiple equilibrium unemployment rates to explain financial crises. The model has equilibria where asset prices are unbounded above. I argue that this is an important feature of any rational-agent explanation of a financial crisis, since for the expansion phase of the crisis to be rational, investors must credibly believe that asset prices could keep increasing forever with positive probability. I explain the sudden crash in asset prices that precipitates a financial crisis as a large shock to expectations that leads to a permanent increase in the unemployment rate.
Obstructive sleep apnea in the adult obese patient: Implications for airway management

Adult obese patients with suspected or sleep test confirmed OSA present a formidable challenge throughout the perioperative period. Life-threatening problems can arise with respect to tracheal intubation, tracheal extubation, and providing satisfactory postoperative analgesia. Tracheal intubation and extubation decisions in obese patients with either a presumptive and/or sleep study diagnosis of OSA must be made within the context that there may be excess pharyngeal tissue that cannot be visualized by routine examination, and the literature indicates an increased risk of intubation difficulty. Regional anesthesia for postoperative pain control is desirable (although such management is not necessary or possible for many of these patients). If opioids are used for the extubated postoperative patient, then one must keep in mind an increased risk of pharyngeal collapse and consider the need for continuous visual and electronic monitoring. The exact management of each sleep apnea patient with regard to intubation, extubation, and pain control requires judgment and is a function of many anesthesia, medical, and surgical considerations.
Carbocation-Forming Reactions in Dimethyl Sulfoxide

Mesylate derivatives of 3-aryl-3-hydroxy-β-lactams and thiolactams react in DMSO-d6 by first-order processes to give alcohol products. Substituent effect studies implicate carbocation intermediates (ion-pairs) that are captured by DMSO-d6 to give transient oxosulfonium ions. Rapid reaction of the oxosulfonium ions with trace amounts of water leads to the alcohol product and regenerates DMSO-d6. H217O labeling studies show that 17O is incorporated into the DMSO. The mesylate derivatives of endo- and exo-2-hydroxy-2-phenylbicyclo[2.2.1]heptan-3-one also react in DMSO-d6 to give the alcohol products. Ion-pair intermediates that capture DMSO giving unstable oxosulfonium ions are again proposed. Exo-2-phenyl-endo-bicyclo[2.2.1]heptyl trifluoroacetate readily eliminates trifluoroacetic acid in DMSO-d6 via a cationic mechanism involving loss of the endo-trifluoroacetate leaving group as well as an exo-hydrogen. The O-methyl oxime derivative of α-chloro-α,α-diphenylacetophenone reacts in DMSO-d6 to give 1-methoxy...
A Natural-Resource-Based View of the Firm

Historically, management theory has ignored the constraints imposed by the biophysical (natural) environment. Building upon resource-based theory, this article attempts to fill this void by proposing a natural-resource-based view of the firm—a theory of competitive advantage based upon the firm's relationship to the natural environment. It is composed of three interconnected strategies: pollution prevention, product stewardship, and sustainable development. Propositions are advanced for each of these strategies regarding key resource requirements and their contributions to sustained competitive advantage.
Reciprocity and Binding in Early Child Grammar

Les precedentes etudes sur l'acquisition de l'anaphore reciproque indiquent que les enfants rencontrent des difficultes lors de l'acquisition de la condition de localite. Dans cette note, l'A. propose une nouvelle analyse des difficultes rencontrees par les enfants pour acquerir la condition de localite, ainsi que la necessite du A-liage de la trace de each
THE DYNAMICAL STATE OF FILAMENTARY INFRARED DARK CLOUDS

The dense, cold gas of Infrared Dark Clouds (IRDCs) is thought to be representative of the initial conditions of massive star and star cluster formation. We analyze 13 CO J = 1 − 0 line emission data from the Galactic Ring Survey of Jackson et al. for two filamentary IRDCs, comparing the mass surface densities derived from 13 CO, �13CO, with those derived from mid-infrared small median filter extinction mapping, �SMF, by Butler & Tan. After accounting for molecular envelopes around the filaments, we � �
Monotonic and Cyclic Fatigue Behavior of a High Performance Ceramic Fiber

Monotonic and cyclic fatigue behavior of fibers are of general interest, regardless of the end use of the product whether in a composite or in a fabric. Study of cyclic fatigue behavior of fibers is particularly difficult because of their small diameter (∼10 μm) and high aspect ratio. In this paper, we report some preliminary results of monotonic tension and tension – tension fatigue behavior of a ceramic fiber: Nextel 312 (Al 2 O 3 -SiO 2 -B 2 O 3 ) fiber. This fiber has a nanocrystalline structure with B 2 O 3 mostly in the form of a glassy phase. The tensile strength data of this fiber showed a Weibull modulus of 4.6, indicating a large degree of variability. Our experiments show clear indication of cyclic loading being more damaging than static loading for Nextel 312. The fracture surface observations of fatigues samples showed some distinctly different features from those observed in fibers subjected to monotonic tension.
Stability and Curving Mechanics of Rail Vehicles

This paper presents a unified treatment of stability and curving mechanics of steel wheel/steel rail vehicles utilizing low order, predominantly linear models. The analysis is applicable to both conventional and self-steering radial passenger trucks. A six degree of freedom truck model is utilized to illustrate the various instability modes that can occur due to the destabilizing influence of a wheelset. It is shown that the individual wheelset mode, the rigid truck mode and the carbody mode are of academic interest only, while the elastically coupled wheelset mode is the one which limits the performance of intercity trucks. Carbody resonance can occur but is controlled by relatively small amounts of damping in the secondary lateral suspension. A four degree of freedom steady-state curving model is used to investigate the influence of shear and bending stiffness on both off and on-flange curving performance. It is shown that a low bending stiffness provides superior on and off-flange curving and that the selection of the shear stiffness depends upon the severity of the curves to be negotiated. A low shear stiffness improves the ability of the truck to stay off the flange while a high shear stiffness results in a “floating” truck which flanges earlier but results in the lowest flange forces and angle of attack once flange contact occurs.
Are Linguists Better Subjects

AbstractWho are the best subjects for judgment tasks intended to test grammatical hypotheses? Michael Devitt ([2006a], [2006b]) argues, on the basis of a hypothesis concerning the psychology of suc...
Continuous-Time Methods in Finance: A Review and an Assessment

I survey and assess the development of continuous-time methods in finance during the last 30 years. The subperiod 1969 to 1980 saw a dizzying pace of development with seminal ideas in derivatives securities pricing, term structure theory, asset pricing, and optimal consumption and portfolio choices. During the period 1981 to 1999 the theory has been extended and modified to better explain empirical regularities in various subfields of finance. This latter subperiod has seen significant progress in econometric theory, computational and estimation methods to test and implement continuous-time models. Capital market frictions and bargaining issues are being increasingly incorporated in continuous-time theory. THE ROOTS OF MODERN CONTINUOUS-TIME METHODS in finance can be traced back to the seminal contributions of Merton ~1969, 1971, 1973b! in the late 1960s and early 1970s. Merton ~1969! pioneered the use of continuous-time modeling in financial economics by formulating the intertemporal consumption and portfolio choice problem of an investor in a stochastic dynamic programming setting. Merton ~1973b! also showed how such a framework can be used to develop equilibrium asset pricing implications, thereby significantly extending the asset pricing theory to richer dynamic settings and expanding the scope of applications of continuous-time methods to study problems in financial economics. 1 Within a span of about 30 years from the publication of Merton’s inf luential papers, continuous-time methods have become an integral part of financial economics. Indeed, in certain core areas in finance ~such as, e.g., asset pricing, derivatives valuation, term structure theory, and portfolio selection! continuoustime methods have proved to be the most attractive way to conduct research and gain economic intuition. The continuous-time approach in these areas has produced models with a rich variety of testable implications. The econometric theory for testing continuous-time models has made rapid strides in the last decade and has thus kept pace with the impressive progress on the theoretical front. One hopes that the actual empirical investigations and estimation using the new procedures will follow suit soon.
Operator counting and eigenvalue distributions for 3D supersymmetric gauge theories

We give further support for our conjecture relating eigenvalue distributions of the Kapustin-Willett-Yaakov matrix model in the large N limit to numbers of operators in the chiral ring of the corresponding supersymmetric three-dimensional gauge theory. We show that the relation holds for non-critical R-charges and for examples with $ \mathcal{N} = {2} $ instead of $ \mathcal{N} = {3} $ supersymmetry where the bifundamental matter fields are nonchiral. We prove that, for non-critical R-charges, the conjecture is equivalent to a relation between the free energy of the gauge theory on a three sphere and the volume of a Sasaki manifold that is part of the moduli space of the gauge theory. We also investigate the consequences of our conjecture for chiral theories where the matrix model is not well understood.
Ultrasensitive Multiplexed MicroRNA Quantification on Encoded Gel Microparticles Using Rolling Circle Amplification

There is great demand for flexible biomolecule analysis platforms that can precisely quantify very low levels of multiple targets directly in complex biological samples. Herein we demonstrate multiplexed quantification of microRNAs (miRNAs) on encoded hydrogel microparticles with subfemtomolar sensitivity and single-molecule reporting resolution. Rolling circle amplification (RCA) of a universal adapter sequence that is ligated to all miRNA targets captured on gel-embedded probes provides the ability to label each target with multiple fluorescent reporters and eliminates the possibility of amplification bias. The high degree of sensitivity achieved by the RCA scheme and the resistance to fouling afforded by the use of gel particles are leveraged to directly detect miRNA in small quantities of unprocessed human serum samples without the need for RNA extraction or target-amplification steps. This versatility has powerful implications for the development of rapid, noninvasive diagnostic assays.
Survivorship bias and attrition effects in measures of performance persistence

We simulate standard tests of performance persistence using alternative returngenerating processes, survival criteria, and test methodologies. When survival depends on performance over several periods, survivorship bias induces spurious reversals, despite the presence of cross-sectional heteroskedasticity in performance. Look-ahead biased methodologies and missing "nal returns typical of U.S. mutual fund datasets can also materially a!ect persistence measures. Our results reinforce previous "ndings that U.S. mutual fund performance is truly persistent. When fund performance is truly persistent, fund attrition a!ects persistence measures, even when the sample includes all nonsurvivor returns. We also examine the speci"cation and power of the various persistence tests. ( 1999 Elsevier Science S.A. All rights reserved.
High-energy neutron spectroscopy on f-electron oxides

Neutron inelastic scattering with the chopper spectrometers at IPNS has been used to measure, for the first time, the ground to excited crystal-field transitions in PrO/sub 2/ (130 meV), BaPrO/sub 3/ (255 meV), and UO/sub 2/ (approx.160 meV). From these measurements we deduce the values of V/sub 4/ = A/sub 4/ (r/sup 4/) and compare both the absolute values and their variation with theoretical estimates. In the case of UO/sub 2/ two peaks are seen, one at 155 and the other at 172 meV. This structure exists both below and above T/sub N/ (30.8K) and we believe is caused by a dynamic Jahn-Teller effect that splits the excited GAMMA/sub 3/ state. 10 refs., 2 figs., 1 tab.
Nearly optimal sparse fourier transform

We consider the problem of computing the k-sparse approximation to the discrete Fourier transform of an n-dimensional signal. We show: An O(k log n)-time randomized algorithm for the case where the input signal has at most k non-zero Fourier coefficients, and An O(k log n log(n/k))-time randomized algorithm for general input signals. Both algorithms achieve o(n log n) time, and thus improve over the Fast Fourier Transform, for any k=o(n). They are the first known algorithms that satisfy this property. Also, if one assumes that the Fast Fourier Transform is optimal, the algorithm for the exactly k-sparse case is optimal for any k = nΩ(1). We complement our algorithmic results by showing that any algorithm for computing the sparse Fourier transform of a general signal must use at least Ω(k log (n/k) / log log n) signal samples, even if it is allowed to perform adaptive sampling.
Using redundancies to find errors

Programmers generally attempt to perform useful work. If they performed an action, it was because they believed it served some purpose. Redundant operations violate this belief. However, in the past, redundant operations have been typically regarded as minor cosmetic problems rather than serious errors. This paper demonstrates that, in fact, many redundancies are as serious as traditional hard errors (such as race conditions or null pointer dereferences). We experimentally test this idea by writing and applying five redundancy checkers to a number of large open source projects, finding many errors. We then show that, even when redundancies are harmless, they strongly correlate with the presence of traditional hard errors. Finally, we show how flagging redundant operations gives a way to detect mistakes and omissions in specifications. For example, a locking specification that binds shared variables to their protecting locks can use redundancies to detect missing bindings by flagging critical sections that include no shared state.
Electromagnetic conductivity imaging with an iterative Born inversion

A technique which uses low frequency electromagnetic fields to image the Earth's conductivity structure between two boreholes is developed. The scheme employs the Born approximation to linearize the integral equation formulation, and a regularized least squares method to invert the data for an initial estimate of the conductivity. A second Born approximation is then applied in a iterative manner to achieve better estimates of the structure. Numerical experiments show that this iterative method improves resolution when compared to normal Born inversion due to the fact that coupling between scattering currents is accounted for. The image quality is shown to be dependent on the operating frequency with the optimal frequency corresponding to the peak of a sensitivity function the authors have termed the Born kernel, which is the product of the primary electric field and the Green's function. >
Analysis of watson's strategies for playing Jeopardy!

Major advances in Question Answering technology were needed for IBM Watson1 to play Jeopardy! at championship level - the show requires rapid-fire answers to challenging natural language questions, broad general knowledge, high precision, and accurate confidence estimates. In addition, Jeopardy! features four types of decision making carrying great strategic importance: (1) Daily Double wagering; (2) Final Jeopardy wagering; (3) selecting the next square when in control of the board; (4) deciding whether to attempt to answer, i.e., "buzz in." Using sophisticated strategies for these decisions, that properly account for the game state and future event probabilities, can significantly boost a player's overall chances to win, when compared with simple "rule of thumb" strategies. This article presents our approach to developing Watson's game-playing strategies, comprising development of a faithful simulation model, and then using learning and Monte-Carlo methods within the simulator to optimize Watson's strategic decision-making. After giving a detailed description of each of our game-strategy algorithms, we then focus in particular on validating the accuracy of the simulator's predictions, and documenting performance improvements using our methods. Quantitative performance benefits are shown with respect to both simple heuristic strategies, and actual human contestant performance in historical episodes. We further extend our analysis of human play to derive a number of valuable and counterintuitive examples illustrating how human contestants may improve their performance on the show.
Optimization of wireless resources for personal communications mobility tracking

In personal communications applications, users communicate via wireless with a wireline network. The wireline network tracks the current location of the user, and can therefore route messages to a user regardless of the user's location. In addition to its impact on signaling within the wireline network, mobility tracking requires the expenditure of wireless resources as well, including the power consumption of the portable units carried by the users and the radio bandwidth used for registration and paging. Ideally, the mobility tracking scheme used for each user should depend on the user's call and mobility pattern, so the standard approach, in which all cells in a registration area are paged when a call arrives, may be wasteful of wireless resources. In order to conserve these resources, the network must have the capability to page selectively within a registration area, and the user must announce his or her location more frequently. We propose and analyze a simple model that captures this additional flexibility. Dynamic programming is used to determine an optimal announcing strategy for each user. Numerical results for a simple one-dimensional mobility model show that the optimal scheme may provide significant savings when compared to the standard approach even when the latter is optimized by suitably choosing the registration area size on a per-user basis. Ongoing research includes computing numerical results for more complicated mobility models and determining how existing system designs might be modified to incorporate our approach.
The illusion of courage in self-predictions: Mispredicting one's own behavior in embarrassing situations†

People exhibit an ‘‘illusion of courage’’ when predicting their own behavior in embarrassing situations. In three experiments, participants overestimated their own willingness to engage in embarrassing public performances in exchange for money when those performances were psychologically distant: Hypothetical or in the relatively distant future. This illusion of courage occurs partly because of cold/hot empathy gaps. That is, people in a relatively ‘‘cold’’ unemotional state underestimate the influence on their own preferences and behaviors of being in a relative ‘‘hot’’ emotional state such as social anxiety evoked by an embarrassing situation. Consistent with this cold/hot empathy gap explanation, putting people ‘‘in touch’’ with negative emotional states by arousing fear (Experiments 1 and 2) and anger (Experiment 2) decreased people’s willingness to engage in psychologically distant embarrassing public performances. Conversely, putting people ‘‘out of touch’’ with social anxiety through aerobic exercise, which reduces state anxiety and increases confidence, increased people’s willingness to engage in psychologically distance embarrassing public performances (Experiment 3). Implications for self-predictions, self-evaluation, and affective forecasting are discussed. Copyright # 2010 John Wiley & Sons, Ltd.
STOLPER-SAMUELSON REVISITED: TRADE AND DISTRIBUTION WITH OLIGOPOLISTIC PROFITS

This paper investigates the distributional impact of international trade when goods markets are oligopolistic and firms partially pass-through changes in tariffs into prices and factor costs for differentiated products. Trade liberalization raises mark-ups and profit shares in the export industry and lowers them in the import-competing industry, while Stolper-Samuelson effects on real prices of primary factors are attenuated or possibly reversed. An extended model shows how “offshoring” (trade in intermediate goods) can potentially increase mark-ups for oligopolistic producers of final goods. The analysis illuminates why business interests generally support trade liberalization policies today, regardless of their countries’ factor abundance.
Globalization, Macroeconomic Performance, and Monetary Policy

The paper argues that many of the exaggerated claims that globalization has been an important factor in lowering inflation in recent years just do not hold up. Globalization does, however, have the potential to be stabilizing for individual economies and has been a key factor in promoting economic growth. The paper then examines four questions about the impact of globalization on the monetary transmission mechanism and arrives at the following answers: (i) Has globalization led to a decline in the sensitivity of inflation to domestic output gaps and thus to domestic monetary policy? No. (ii) Are foreign output gaps playing a more prominent role in the domestic inflation process, so that domestic monetary policy has more difficulty stabilizing inflation? No. (iii) Can domestic monetary policy still control domestic interest rates and so stabilize both inflation and output? Yes. (iv) Are there other ways, besides possible influences on inflation and interest rates, in which globalization may have affected the transmission mechanism of monetary policy? Yes.
POTENTIATION OF NERVE BLOCK IN VIVO BY PHYSIOLOGICAL ADJUVANTS IN THE SOLUTION

One hundred and seventy-four rats received a standardized 0.4-ml injection into the left infraorbital nerve and all solutions contained lignocaine 0.25 gdl−1. In groups 1–4, the solutions were isoosmotic and contained, besides sodium chloride, potassium chloride 0 or 4 mmol litre−1 and glucose 0 or 20 mmol litre−1 (0 or 360 gdl−1). For groups 5–8, the solutions were hypoosmotic, containing sodium chloride to 0.6 of normal tonicity, but were otherwise identical to solutions 1–4. Presence and duration of sensory block were determined from the reflex sublingual electromyographic response to periodic homolateral and contralateral electrical stimulation of the upper lip. In groups 1–4, the presence of potassium chloride 4 mmol litre−1 approximately doubled the duration of blockade (P
Numerical Calculation of Unsteady Transonic Potential Flow over Helicopter Rotor Blades

The small disturbance potential equation appropriate to a helicopter in forward flight is derived. This equation then is solved for the flow over a nonlifting transonic rotor blade, using a completely implicit scheme that is an extension of the Murman-Cole mixed difference technique. The flow in the tip region is most unsteady in the decelerating flow region, after the blade passes the \J/ - 90°azimuthal station. The unsteadiness appears to be caused by expansion and compression waves that move slowly upstream of the blade as the relative incident flow decelerates. The influence of aspect ratio, advance ratio, and Mach number on this process is discussed.
Gravitational Radiation from Gamma-Ray Burst Progenitors

We study gravitational radiation from various proposed gamma-ray burst (GRB) progenitor models, in particular compact mergers and massive stellar collapses. These models have in common a high angular rotation rate, and the final stage involves a rotating black hole and accretion disk system. We consider the in-spiral, merger, and ringing phases, and for massive collapses, we consider the possible effects of asymmetric collapse and break up, as well as bar-mode instabilities in the disks. We evaluate the orders of magnitude of the strain and frequency of the gravitational waves expected from various progenitors, at distances based on occurrence rate estimates. Based on simplifying assumptions, we give estimates of the probability of detection of gravitational waves by the advanced LIGO system from the different GRB scenarios.
Technical progress and aggregate fluctuations

Abstract We compare the cyclical fluctuations exhibited by a stochastic growth model under various stochastic processes governing technical change, all of which are highly autocorrelated. The results obtained are quite sensitive to the precise form of this stochastic process. In particular, the results depend on whether growth is deterministic or stochastic and, in each case, are quite sensitive to the persistence of an innovation. The model does a relatively poor job of accounting for features of observed business cycles when technical change is difference-stationary and does a better job when technical change is trend-stationary but highly autocorrelated.
Hamilton cycles in 3-out

Let G3-out denote the random graph on vertex set [n] in which each vertex chooses three neighbors uniformly at random. Note that G3-out has minimum degree 3 and average degree 6. We prove that the probability that G3-out is Hamiltonian goes to 1 as n tends to infinity. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2009
Rational Prepayment and the Valuation of Mortgage-Backed Securities

This article presents a new model of mortgage prepayments, based on rational decisions by mortgage holders. These mortgage bolders face beterogeneous transaction costs, which are explicitly modeled. The model is estimated using a version of Hansen’s (1982) generalized method of moments, and is sbown to capture many of the empirical features of mortgage prepayment. Estimation results indicate that mortgage holders act as tbougb tbey face transaction costs tbat far exceed tbe explicit Costs usually incurred on refinancing. They also wait an average of more than a year before refinancing, even when it is optimal to do so. The model fits observed prepayment behavior as well as thee recent empirical model of Schwartz and Torous (1989). Implications for pricing mortgage-backed securities are’ discussed
U.S.-Mexican Trade in Winter Vegetables and Illegal Immigration

This paper presents an integrated approach to U.S.-Mexican trade in a labor-intensive commodity (fresh winter tomatoes) and illegal immigration of agricultural labor. A seven-equation econometric model is developed that includes excess demand (U.S. import) and supply (Mexican export) equations for fresh winter tomatoes, U.S. demand and Mexican supply equations for apprehensible individuals, intercountry price and wage relationship equations, and a U.S. Border Patrol apprehension effort equation. The empirical results indicate that both U.S. and Mexico economic conditions affect the number of apprehended illegal Mexican aliens. The results also indicate that immigration and trade policies affect apprehensions.
Productivity or Endowments? Sectoral Evidence for Hong Kong's Aggregate Growth*

The author provides sectoral evidence that sheds new light on the current debate regarding the sources of growth of the East Asian miracle. The author tests both the productivity-driven and endowment-driven hypotheses using Hong Kong's sectoral data. The results show that most of the growth in the services sector is driven by the rapidly accumulating capital endowments, and not by productivity growth. In addition, productivity growth in the manufacturing sector is also unimpressive. The manufacturing sector is more labor intensive and its growth is hindered by the reallocation of resources into the services sector as a result of the growth of capital endowments and imports. Overall, sectoral evidence supports the endowment-driven hypothesis for Hong Kong's aggregate growth.