cssi/SciSciGPT-SciSciNet huggingface dataset:
Real Effects of Movements in Nominal Exchange Rates: Application to the Asian Crisis

This paper analyzes the ad hoc decision of three Asian countries to peg their currency to the U.S. dollar prior to the Asian crisis. It uses the Sjaastad model to estimate the optimal basket weights for Thailand, Korea, and Singapore. The analysis in this paper differs from the optimal basket research since we are not searching for an ad hoc optimal basket; rather, the basket is the solution to the problem. For Thailand and Korea, the correct weights of the dollar in the basket are estimated to be 44 and 65 percent, respectively, which differ significantly from the actual weight of 100 percent for the U.S. dollar in their currency basket prior to the 1997 Asian crisis. Singapore, with a weight of 85 percent for the U.S. currency, is closer to a dollar peg, and therefore was less affected by the large depreciation of the European currencies and the yen toward the dollar that occurred prior to the Asian exchange rate crisis. Besides the fact that Singapore had better economic fundamentals prior to the crisis, the fact that the optimal basket for that country is closer to a dollar peg is an additional reason why its economy was less severely hit by the crisis.
Arbitrating and mediating disputes : benchmarking arbitration and mediation regimes for commercial disputes related to foreign direct investment

An effective commercial arbitration regime matters for foreign investors. It gives parties the autonomy to create a dispute resolution system tailored to increasingly complex disputes. Foreign investors view arbitration as a way to mitigate risks by providing legal certainty on enforcement rights, due process, and access to justice. The Arbitrating and Mediating Disputes indicators assess the legal and institutional framework for commercial arbitration, mediation, and conciliation regimes in 100 economies. All surveyed economies recognize arbitration as a tool for resolving commercial disputes and only nine economies have not acceded to the New York Convention on the Recognition and Enforcement of Foreign Arbitral Awards. In the Arbitrating and Mediating Disputes indicators, High Income OECD and Eastern Europe and Central Asia are the regions that reformed their laws on alternative dispute resolution the most between 2011 and 2012. The data also show that, globally, arbitration proceedings take 326 days on average, while recognition and enforcement proceedings of foreign arbitral awards take 557 days on average. The Arbitration and Mediating Disputes indicators are significantly correlated with perception data on the importance of alternative dispute resolution, as well as other measures such as total foreign direct investment inflows and inflows per capita, the Doing Business 2013 Enforcing Contracts data, the World Bank Group's Governance Indicators, the World Economic Forum's Global Competitiveness Indicators, and the Multilateral Investment Guarantee Agency's World Investment and Political Risk data. The paper concludes by identifying several opportunities for improvement, such as greater flexibility for domestic arbitration regimes, faster arbitration proceedings, and better domestic court capabilities.
Compliant coordination control of two moving industrial robots

When two robots execute coordinated motion in industrial application such as assembly, not only is the specification of the desired motion of each robot's end effector required, but also that of the desired contact force exerted on the end effectors. The involvement of the forces is the motivation for a consideration of compliance. The compliant coordination control scheme of two moving robots is presented. One robot is equipped with a force/torque sensing wrist, which provides force feedback signals and permits the fine coordinated motion control of complex assembly tasks. A control strategy is derived so that the measured force/torque can be used to modify the trajectory of one of the robots. This control scheme can be realized in real time by using the proposed computational structure. The system stability is related to the force-displacement conversion gain in the forward path. An experiment that screws a moving nut onto a moving bolt has been carried out as an illustration. >
Adaptive control of space-based robot manipulators

A control method is presented that achieves globally stable trajectory tracking in the presence of uncertainties in the inertial parameters of the system. The 15-degree-of-freedom (DOF) system dynamics are divided into two components: a 9-DOF invertible portion and 6-DOF noninvertible portion. A controller is then designed to achieve trajectory tracking of the invertible portion of the system, which consists of the manipulator joint positions and the orientation of the base. The motion of the noninvertible portion is bounded but otherwise unspecified. This portion of the system consists of the position of the robot's base and the position of the reaction wheels. A simulation is presented to demonstrate the effectiveness of the controller. A quadratic polynomial is used to generate the desired trajectory to illustrate the trajectory tracking capability of the controller. >
Bifunctional antitumor agents. Derivatives of pyrrolo[9, 10-b]phenanthrene—A DNA intercalative delivery template

Abstract The preparation and intercalative ability of the pyrrolo[9, 10- b ]phenanthrene nucleus is described. Functionalization of the nucleus was achieved using standard indole chemistry. The utility of this template as a DNA intercalating drug delivery system is demonstrated by synthesis of a derived bis-chloroethylamine alkylating system and a hybrid DNA interactive enediyne system.
The Secular Bar-Mode Instability in Rapidly Rotating Stars Revisited

Uniformly rotating, homogeneous, incompressible Maclaurin spheroids that spin sufficiently rapidly are secularly unstable to nonaxisymmetric, bar-mode perturbations when viscosity is present. The intuitive explanation is that energy dissipation by viscosity can drive an unstable spheroid to a stable, triaxial configuration of lower energy—a Jacobi ellipsoid. But what about rapidly rotating compressible stars? Unlike incompressible stars, which contain no internal energy and therefore immediately liberate all the energy dissipated by viscosity, compressible stars have internal energy and can retain the dissipated energy as internal heat. Now compressible stars that rotate sufficiently rapidly and also manage to liberate this dissipated energy very quickly are known to be unstable to bar-mode perturbations, like their incompressible counterparts. But what is the situation for rapidly rotating compressible stars that have very long cooling timescales, so that all the energy dissipated by viscosity is retained as heat, and the total energy of the star remains constant on a secular (viscous) evolution timescale? Are such stars also unstable to the nonlinear growth of bar modes, or is the viscous heating sufficient to cause them to expand, drive down the ratio of rotational kinetic to gravitational potential energy /|W| ∝ R, where Req is the equatorial radius, and turn off the instability before it gets underway? Alternatively, if the instability still arises in such stars, at what rotation rate do they become unstable, and to what final state do they evolve? We provide definitive answers to these questions in the context of the compressible ellipsoid model for rotating stars. The results should serve as useful guides for numerical simulations that solve the exact Navier-Stokes equations in 3 + 1 dimensions for rotating stars containing viscosity.
Black holes in three dimensional higher spin gravity: a review

We review recent progress in the construction of black holes in three dimensional higher spin gravity theories. Starting from spin-3 gravity and working our way toward the theory of an infinite tower of higher spins coupled to matter, we show how to harness higher spin gauge invariance to consistently generalize familiar notions of black holes. We review the construction of black holes with conserved higher spin charges and the computation of their partition functions to leading asymptotic order. In view of the anti-de Sitter/conformal field theory (CFT) correspondence as applied to certain vector-like conformal field theories with extended conformal symmetry, we successfully compare to CFT calculations in a generalized Cardy regime. A brief recollection of pertinent aspects of ordinary gravity is also given.This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’.
Fault-tolerant de Bruijn and shuffle-exchange networks

This paper addresses the problem of creating a fault-tolerant interconnection network for a parallel computer. Three topologies, namely, the base-2 de Bruijn graph, the base-m de Bruijn graph, and the shuffle-exchange, are studied. For each topology an N+k node fault-tolerant graph is defined. These fault-tolerant graphs have the property that given any set of k node faults, the remaining N nodes contain the desired topology as a subgraph. All of the constructions given are the best known in terms of the degree of the fault-tolerant graph. We also investigate the use of buses to reduce the degrees of the fault-tolerant graphs still further. >
Carbon dioxide and supramolecular chemistry

Concepts and techniques of supramolecular chemistry are applied to the century-old chemistry between CO2 and amines to design novel sensing systems and nanoscale, self-assembling polymeric materials and networks.
Turning Art Into Mere Illustration Concretizing Art Renders Its Influence Context Dependent

Broadly speaking, artworks are accorded a special significance and are recognized as powerful communication tools. In the current research, the authors posit that the "specialness" of artworks may be diminished simply by emphasizing that which is depicted in them. This emphasis results in the artwork being viewed as a mere illustration rather than a work of art. Specifically, the influence of an "artwork as art" is context independent, but the influence of an "artwork as illustration" is context dependent. The authors demonstrate this phenomenon in two experiments, in the context of products associated with artworks. In a third experiment, they further demonstrate that an abstract (concrete) mind-set aligns with the influence of an artwork as art (illustration).
Numerical and laboratory simulation of fault motion and earthquake occurrence

Simple linear rheologies were used with elastic forces driving the main events and viscoelastic forces being important for aftershock and creep occurrence. Friction and its dependence on velocity, stress, and displacement also plays a key role in determining how, when, and where fault motion occurs. The discussion of the qualitative behavior of the simulators focuses on the manner in which energy was stored in the system and released by the unstable and stable sliding processes. The numerical results emphasize the statistics of earthquake occurrence and the correlations among source parameters.
Persistence of freeness for Lie pseudogroup actions

The action of a Lie pseudogroup \(\mathcal{G}\) on a smooth manifold M induces a prolonged pseudogroup action on the jet spaces J n of submanifolds of M. We prove in this paper that both the local and global freeness of the action of \(\mathcal{G}\) on J n persist under prolongation in the jet order n. Our results underlie the construction of complete moving frames and, indirectly, their applications in the identification and analysis of the various invariant objects for the prolonged pseudogroup actions.
Electrophilic Activation of Alkenes by Platinum(II): So Much More Than a Slow Version of Palladium(II)

The electrophilic activation of alkenes by transition-metal catalysts is a fundamental step in a rapidly growing number of catalytic processes. Although palladium is the best known metal for this purpose, the special properties of its third-row cousin platinum (strong metal-ligand bonds and slow substitution kinetics) have enabled the development of transformations that are initiated by addition to the C=C bonds by protic carbon, nitrogen, oxygen, and phosphorus nucleophiles, as well as alkene or arene nucleophiles. Additionally, reactivity profiles, which are often unique to platinum, provide wholly new reaction products. This Review concerns platinum-catalyzed electrophilic alkene activation reactions, with a special emphasis on the mechanistic properties of known systems, on the differences between platinum and palladium catalysts, and on the prospects for the development of new systems.
Trade Costs, Asset Market Frictions, and Risk Sharing

I use bilateral import data to test for and quantify the importance of trade costs and asset market frictions in explaining the failure of perfect international consumption risk sharing. I find that while frictions in international asset markets significantly impede optimal consumption risk sharing between developed and developing countries over the period 1970–2000, developed countries are close to optimal risk sharing with each other. Trade costs, in contrast, sig
Extended wave propagators as pulsed-beam communication channels

Let P(xr-xe) be the causal propagator for the wave equation, representing the signal received at the spacetime point xr due to an impulse emitted at the spacetime point x e. Such processes are highly idealized since no signal can be emitted or received at a precise point in space and at a precise time. We propose a simple and compact model for extended emitters and receivers by continuing P to an analytic function Pmacr(zr-ze), where ze=xe+iye represents a circular pulsed-beam emitting antenna centered at xe and radiating in the spatial direction of ye while zr=xr-iyr represents a circular pulsed-beam receiving antenna centered at xr and receiving from the spatial direction of yr. The space components ye,yr of ye,yr give the spatial orientations and radii of the antennas, while their time components se, sr represent the time a signal takes to propagate along the antennas between the center and the boundary. The analytic propagator Pmacr represents the transmission amplitude, forming a communication channel. Causality requires that the extension/orientation 4-vectors ye and yr belong to the future cone V+, so that ze and zr belong to the future tube and the past tube in complex space-time, respectively. The imaginary "retarded time" Te=s e-|ye|/c represents the duration of the emitted pulse, and Tr=sr-|yr|/c represents the integration time for the received pulse. The bandwidths of the antennas are 1/Te and 1/Tr, respectively. The invariance of Pmacr under imaginary spacetime translations (zerarrze+ieta, zrrarrzr +ieta) has nontrivial consequences
Pro-poor targeting and accountability of local governments in West Bengal

A commonly alleged pitfall of decentralization is that poverty, socio-economic inequality and lack of political competition allow local elites to capture local governments. This hypothesis is empirically examined using a longitudinal sample of 89 West Bengal villages concerning targeting of credit, agricultural input kits, employment programs and fiscal grants spanning the period 1978–98. Higher poverty, land inequality and low caste composition of the poor was associated with negligible adverse effects on targeting of private goods to the poor within villages, but with lower employment generation out of allotted funds, and significantly lower allocation of resources to the village as a whole. Political competition or literacy levels among the poor were not systematically related to targeting.
Covariance of the one-dimensional mass power spectrum

We analyse the covariance of the one-dimensional mass power spectrum along lines of sight. The covariance reveals the correlation between different modes of fluctuations in the cosmic density field and gives the sample variance error for measurements of the mass power spectrum. For Gaussian random fields, the covariance matrix is diagonal. As expected, the variance of the measured one-dimensional mass power spectrum is inversely proportional to the number of lines of sight that are sampled from each random field. The correlation between lines of sight in a single field may alter the covariance. However, lines of sight that are sampled far apart are only weakly correlated, so that they can be treated as independent samples. Using N-body simulations, we find that the covariance matrix of the one-dimensional mass power spectrum is not diagonal for the cosmic density field due to the non-Gaussianity and that the variance is much higher than that of Gaussian random fields. From the covariance, one will be able to determine the cosmic variance in the measured one-dimensional mass power spectrum as well as to estimate how many lines of sight are needed to achieve a target precision.
Visual Information Processing: The Structure and Creation of Visual Representations

For human vision to be explained by a computational theory, the first question is plain: What are the problems that the brain solves when we see? It is argued that vision is the construction of efficient symbolic descriptions from images of the world. An important aspect of vision is therefore the choice of representations for the different kinds of information in a visual scene. An overall framework is suggested for extracting shape information from images, in which the analysis proceeds through three representations: (1) the primal sketch, which makes explicit the intensity changes and local two-dimensional geometry of an image; (2) the 2 1/2-D sketch, which is a viewer-centred representation of the depth, orientation and discontinuities of the visible surfaces; and (3) the 3-D model representation, which allows an object-centred description of the three-dimensional structure and organization of a viewed shape. The critical act in formulating computational theories for processes capable of constructing these representations is the discovery of valid constraints on the way the world behaves, that provide sufficient additional information to allow recovery of the desired characteristic. Finally, once a computational theory for a process has been formulated, algorithms for implementing it may be designed, and their performance compared with that of the human visual processor.
Understanding correlated electron systems by a classification of Mott insulators

Abstract This paper surveys the physics of systems proximate to Mott insulators, and presents a classification using conventional and topological order parameters. This classification offers a valuable perspective on a variety of conducting correlated electron systems, from the cuprate superconductors to the heavy fermion compounds. Connections are drawn, and distinctions made, between collinear/non-collinear magnetic order, bond order, neutral spin 1/2 excitations in insulators, electron Fermi surfaces which violate Luttinger’s theorem, fractionalization of the electron, and the fractionalization of bosonic collective modes. Two distinct categories of Z 2 gauge theories are used to describe the interplay of these orders. Experimental implications for the cuprates are briefly noted, but these appear in more detail in a companion review paper (S. Sachdev, cond-mat/0211005).
Atmospheric Lensing and Oblateness Effects during an Extrasolar Planetary Transit

Future high-precision photometric measurements of transiting extrasolar planets promise to tell us much about the characteristics of these systems. We examine how atmospheric lensing and (projected) planet oblateness/ellipticity modify transit light curves. The large density gradients expected in planet atmospheres can offset the unfavorably large observer lens–to–source lens distance ratio and allow the existence of caustics. Under such conditions of strong lensing, which we quantify with an analytic expression, starlight from all points in the planet’s shadow is refracted into view, producing a characteristic slowing down of the dimming at ingress (vice versa for egress). A search over several parameters, such as the limb-darkening profile, the planet radius, the transit speed, and the transit geometry, cannot produce a nonlensed transit light curve that can mimic a lensed light curve. The fractional change in the diminution of starlight is approximately the ratio of atmospheric scale height to planet radius, expected to be 1% or less. The lensing signal varies strongly with wavelength—caustics are hidden at wave bands where absorption and scattering are strong. Planet oblateness induces an asymmetry to the transit light curve about the point of minimum flux, which varies with the planet orientation with respect to the direction of motion. The fractional asymmetry is at the level of 0.5% for a projected oblateness of 10%, independent of whether or not lensing is important. For favorable ratios of planet radius to stellar radius (i.e., gas giant planets), the above effects are potentially observable with future space-based missions. Such measurements could constrain the planet shape and its atmospheric scale height, density, and refractive coefficient, providing information on its rotation, temperature, and composition. We have examined a large range of planetary system parameter space including the planetary scale height and orbital distance. For HD 209458b, the only currently known transiting extrasolar planet, caustics are absent because of the very small lens-source separation (and a large scale height caused by a high temperature from the small separation). Its oblateness is also expected to be small because of the tidal locking of its rotation to orbital motion. Finally, we provide estimates of other variations to transit light curves that could be of comparable importance—including rings, satellites, stellar oscillations, star spots, and weather. Subject headings: gravitational lensing — planetary systems — stars: atmospheres
A scalable bootstrap for massive data

Summary The bootstrap provides a simple and powerful means of assessing the quality of estimators. However, in settings involving large data sets—which are increasingly prevalent—the calculation of bootstrap-based quantities can be prohibitively demanding computationally. Although variants such as subsampling and the m out of n bootstrap can be used in principle to reduce the cost of bootstrap computations, these methods are generally not robust to specification of tuning parameters (such as the number of subsampled data points), and they often require knowledge of the estimator's convergence rate, in contrast with the bootstrap. As an alternative, we introduce the ‘bag of little bootstraps’ (BLB), which is a new procedure which incorporates features of both the bootstrap and subsampling to yield a robust, computationally efficient means of assessing the quality of estimators. The BLB is well suited to modern parallel and distributed computing architectures and furthermore retains the generic applicability and statistical efficiency of the bootstrap. We demonstrate the BLB's favourable statistical performance via a theoretical analysis elucidating the procedure's properties, as well as a simulation study comparing the BLB with the bootstrap, the m out of n bootstrap and subsampling. In addition, we present results from a large-scale distributed implementation of the BLB demonstrating its computational superiority on massive data, a method for adaptively selecting the BLB's tuning parameters, an empirical study applying the BLB to several real data sets and an extension of the BLB to time series data.
Ovarian Torsion in Pediatric Patients: A Review of Eleven Years' Experience.

Objectives. To examine associated clinical features and evaluate published criteria regarding volumetric diagnosis of ovarian torsion (OT). Methods. Retrospective case-control study of patients presenting to an emergency department who underwent pelvic imaging for acute abdominal or pelvic pain. Cases were found to have OT at surgery. Controls received clinical diagnosis of either acute pelvic pain or ovarian cyst. Results. The sensitivity for OT using a cutoff AV of 75 mL was 18% (95% CI = 7% to 30%); specificity was 93% (95% CI = 85% to 100%). The ratio of affected-side to unaffected-side AV of >15 had a sensitivity of 16% (95% CI = 5% to 27%); specificity was 98% (95% CI = 93% to 100%). Conclusions. The published criteria regarding the volumetric diagnosis of OT were inadequately sensitive for detecting OT. However, an affected-side AV >75 mL and an AV ratio >15 were reasonably specific.
A new string in ten dimensions

I suggest the possibility of a new string in ten dimensions. Evidence for this string is presented both from orientifold physics and from K-theory, along with a mystery concerning the M-theory description. Motivated by this possibility, some novel aspects of decoupling limits in heterotic/type I theories are described; specifically, the decoupled theory on type I D-strings is argued to be three-dimensional rather than two-dimensional. These decoupled theories provide the matrix model definitions of the heterotic/type I strings.
Book-Tax Differences as an Indicator of Financial Distress

SYNOPSIS: We contend that tax-related information, which has not yet been considered by extant research, can significantly improve bankruptcy prediction. We investigate the association between abnormal changes in book-tax differences (BTDs) and bankruptcy using a hazard model and out-of-sample testing as in Shumway (2001). We find that information regarding abnormal changes in BTDs significantly increases our ability to ex ante identify firms that have an increased likelihood of going bankrupt in the coming five-year period. The information provided by BTDs significantly adds information to traditional models for predicting bankruptcy, such as that proposed by Ohlson (1980), and also expands the prediction window beyond the traditional two-year time frame.
GaN HFETs on SiC Substrates Grown by Nitrogen Plasma MBE

AlGaN/GaN heterojunction field effect transistors (HFETs) have recently demonstrated power-handling capabilities exceeding by almost an order of magnitude those of GaAs-pHEMTs. In addition, several groups have reported that low-noise performance of these high power devices almost matches that of the state of the art GaAs-pHEMTs, despite the relative immaturity of GaN HFET technology. A growing demand for GaN HFET parts that has been created by the recent promising performance of GaN HFETs led to the expansion of our research effort to include a small-scale production capability. Device results and run-to-run reproducibility data presented in this paper clearly demonstrate, that plasma assisted MBE is a viable tool for production of GaN HFETs on SiC wafers.
Holographic entanglement entropy and renormalization group flow

Using holography, we study the entanglement entropy of strongly coupled field theories perturbed by operators that trigger an RG flow from a conformal field theory in the ultraviolet (UV) to a new theory in the infrared (IR). The holographic duals of such flows involve a geometry that has the UV and IR regions separated by a transitional structure in the form of a domain wall. We address the question of how the geometric approach to computing the entanglement entropy organizes the field theory data, exposing key features as the change in degrees of freedom across the flow, how the domain wall acts as a UV region for the IR theory, and a new area law controlled by the domain wall. Using a simple but robust model we uncover this organization, and expect much of it to persist in a wide range of holographic RG flow examples. We test our formulae in two known examples of RG flow in 3+1 and 2+1 dimensions that connect non-trivial fixed points.
Perfect matchings via uniform sampling in regular bipartite graphs

In this article we further investigate the well-studied problem of finding a perfect matching in a regular bipartite graph. The first nontrivial algorithm, with running time O(mn), dates back to Konig's work in 1916 (here m=nd is the number of edges in the graph, 2n is the number of vertices, and d is the degree of each node). The currently most efficient algorithm takes time O(m), and is due to Cole et al. l2001r. We improve this running time to O(min{m, n2.5ln n/d}); this minimum can never be larger than O(n1.75√ln n). We obtain this improvement by proving a uniform sampling theorem: if we sample each edge in a d-regular bipartite graph independently with a probability p = O(n ln n/d2) then the resulting graph has a perfect matching with high probability. The proof involves a decomposition of the graph into pieces which are guaranteed to have many perfect matchings but do not have any small cuts. We then establish a correspondence between potential witnesses to nonexistence of a matching (after sampling) in any piece and cuts of comparable size in that same piece. Karger's sampling theorem l1994a, 1994br for preserving cuts in a graph can now be adapted to prove our uniform sampling theorem for preserving perfect matchings. Using the O(m√n) algorithm (due to Hopcroft and Karp l1973r) for finding maximum matchings in bipartite graphs on the sampled graph then yields the stated running time. We also provide an infinite family of instances to show that our uniform sampling result is tight up to polylogarithmic factors (in fact, up to ln2n).
Production of hypervelocity stars through encounters with stellar‐mass black holes in the Galactic Centre

Stars within 0.1 pc of the supermassive black hole (BH) Sgr A ∗ at the Galactic Centre are expected to encounter a cluster of stellar-mass BHs that have segregated to that region. Some of these stars will scatter off an orbiting BH and be kicked out of the Galactic Centre with velocities up to ∼2000 km s −1 . We calculate the resulting ejection rate of hypervelocity stars (HVSs) by this process under a variety of assumptions, and find it to be comparable to the tidal disruption rate of binary stars by Sgr A ∗ , first discussed by Hills. Under some conditions, this novel process is sufficient to account for all of the hypervelocity B stars observed in the halo, and may dominate the production rate of all HVSs with lifetimes much less than the relaxation time-scale at a distance ∼2 pc from Sgr A ∗ (� 2 Gyr). Since HVSs are produced by at least two unavoidable processes, the statistics of HVSs could reveal bimodal velocity and mass distributions, and can constrain the distribution of BHs and stars in the innermost 0.1 pc around Sgr A ∗ .
Chemical evolution of the juvenile universe

Models of average Galactic chemical abundances are in good general agreement with observations for [Fe/H] > –1.5, but there are gross discrepancies at lower metallicities. Only massive stars contribute to the chemical evolution of the ‘juvenile universe’ corresponding to [Fe/H] ≲ –1.5. If Type II supernovae (SNe II) are the only relevant sources, then the abundances in the interstellar medium of the juvenile epoch are simply the sum of different SN II contributions. Both low-mass (~8–11 M_⊙) and normal (~12–25 M_⊙) SNe II produce neutron stars, which have intense neutrino-driven winds in their nascent stages. These winds produce elements such as Sr, Y and Zr through charged-particle reactions (CPR). Such elements are often called the ‘light r-process elements’, but are considered here as products of CPR and not the r process. The observed absence of production of the low-A elements (Na through Zn including Fe) when the true r-process elements (Ba and above) are produced requires that only low-mass SNe II be the site if the r process occurs in SNe II. Normal SNe II produce the CPR elements in addition to the low-A elements. This results in a two-component model that is quantitatively successful in explaining the abundances of all elements relative to hydrogen for –3 ≲ [Fe/H] ≲ –1.5. This model explicitly predicts that [Sr/Fe] ≥ –0.32. Recent observations show that there are stars with [Sr/Fe] ≲ –2 and [Fe/H] < –3. This proves that the two-component model is not correct and that a third component is necessary to explain the observations. The production of CPR elements associated with the formation of neutron stars requires that the third component must be massive stars ending as black holes. It is concluded that stars of ~25–50 M_⊙ (possibly up to ~100 M_⊙) are the appropriate candidates. These produce hypernovae (HNe) that have very high Fe yields and are observed today. Stars of ~140–260 M_⊙ are completely disrupted upon explosion. However, they produce an abundance pattern greatly deficient in elements of odd atomic numbers, which is not observed, and therefore they are not considered as a source here. Using a Salpeter initial mass function, it is shown that HNe are a source of Fe that far outweighs normal SNe II, with the former and the latter contributing ~24% and ~9% of the solar Fe abundance, respectively. It follows that the usual assignment of of the solar Fe abundance to normal SNe II is not correct. This leads to a simple three-component model including low-mass and normal SNe II and HNe, which gives a good description of essentially all the data for stars with [Fe/H] ≲ –1.5. We conclude that HNe are more important than normal SNe II in the chemical evolution of the low-A elements from Na through Zn (including Fe), in sharp distinction to earlier models.
Superstars and Mediocrities: Market Failure in The Discovery of Talent

A basic problem facing most labor markets is that workers can neither commit to long-term wage contracts nor can they self …nance the costs of production. I study the eects of these imperfections when talent is industry-speci…c, it can only be revealed on the job, and once learned becomes public information. I show that …rms bid exces- sively for the pool of incumbent workers at the expense of trying out new talent. The workforce is then plagued with an unfavorable selection of individuals: there are too many mediocre workers, whose talent is not high enough to justify them crowding out novice workers with lower expected talent but with more upside potential. The result is an ine¢ ciently low level of output coupled with higher wages for known high talents. This problem is most severe where information about talent is initially very imprecise and the complementary costs of production are high. I argue that high incomes in pro- fessions such as entertainment, management, and entrepreneurship, may be explained by the nature of the talent revelation process, rather than by an underlying scarcity of talent. (JEL D30, J31, J6, M5)
Synthesis of 5‐benzyl and 5‐benzyloxybenzyl‐3′‐azido‐2′,3′‐dideoxyuridine and their analogues as potential anti‐AIDS agents

5-Benzyl and 5-benzyloxybenzyl-substituted 3′-azido-2′,3′-dideoxyuridine, (8a and 8b), 3′-halogeno-2′,3′-dideoxyuridine, 9a, 9b, 10a, 10b, 11a and 11b, and 2′,3′-dideoxyuridine, 12a and 12b, of Scheme I were synthesized as potential anti AIDS agents. Synthesis of epimers of 8a and 8b, 5-benzyl- and 5-benzyloxybenzyl-1-(3′-azido-2′,3′-dideoxy-β-D-threo-pentafuranosyl)uracil, 15a and 15b, and 5-benzyl- and 5-benzyloxy-5′-azido-2′,5′-dideoxyuridine, 16a and 16b, shown in Scheme II, were also reported.
A supersymmetric grand unified model with noncompact horizontal symmetry

In a supersymmetric SU(5) grand unified model with a horizontal symmetry SU(1, 1), we discuss spontaneous generation of generations to produce three chiral generations of quarks and leptons and one generation of higgses by using one structure field with a half-integer spin of SU(1, 1) and two structure fields with integer spins. In particular, the colored higgses can disappear without fine-tuning. The difference of the Yukawa coupling matrices between the down-type quarks and charged leptons is discussed. We show that some special SU(1, 1) weight assignments include R-parity as a discrete subgroup, and R-parity remains even after we take into account the SU(1, 1) breaking effects from all the VEVs of the structure and matter fields. The assignments forbid the baryon and/or lepton number violating terms except a superpotential quartic term including a coupling of two lepton doublets and two up-type higgses. We discuss how to generate sizable neutrino masses. We show that the proton decay derived from the colored higgses is highly suppressed.
Quantifying eventual consistency with PBS

Data replication results in a fundamental trade-off between operation latency and consistency. At the weak end of the spectrum of possible consistency models is eventual consistency, which provides no limit to the staleness of data returned. However, anecdotally, eventual consistency is often "good enough" for practitioners given its latency and availability benefits. In this work, we explain this phenomenon and demonstrate that, despite their weak guarantees, eventually consistent systems regularly return consistent data while providing lower latency than their strongly consistent counterparts. To quantify the behavior of eventually consistent stores, we introduce Probabilistically Bounded Staleness (PBS), a consistency model that provides expected bounds on data staleness with respect to both versions and wall clock time. We derive a closed-form solution for version-based staleness and model real-time staleness for a large class of quorum replicated, Dynamo-style stores. Using PBS, we measure the trade-off between latency and consistency for partial, non-overlapping quorum systems under Internet production workloads. We quantitatively demonstrate how and why eventually consistent systems frequently return consistent data within tens of milliseconds while offering large latency benefits.
Wakimoto modules for twisted affine lie algebras

We construct Wakimoto modules for twisted a!ne Lie algebras , and interpret this construction in terms of vertex algebras and their twisted modules. Using the Wakimoto construction, we prove the Kac-Kazhdan conjecture on the characters of irreducible modules with generic critical highest weights in the twisted case. We provide explicit formulas for the twisted fields in the case of A (2) .
Double Patterning Layout Decomposition for Simultaneous Conflict and Stitch Minimization

Double patterning lithography (DPL) is considered as a most likely solution for 32 nm/22 nm technology. In DPL, the layout patterns are decomposed into two masks (colors), and manufactured through two exposures and etch steps. If the spacing between two features (polygons) is less than certain minimum coloring distance, they have to be assigned opposite colors. However, a proper coloring is not always feasible because two neighboring patterns within the minimum distance may be in the same mask due to complex pattern configurations. In that case, a feature may need to be split into two parts to resolve the conflict, resulting in stitch insertion which causes yield loss due to overlay and line-end effect. While previous layout decomposition approaches perform coloring and splitting separately, in this paper, we propose a simultaneous conflict and stitch minimization algorithm with an integer linear programming (ILP) formulation. Since ILP is in class NP-hard, the algorithm includes three speed-up techniques: (1) grid merging; (2) independent component computation; and (3) layout partition. In addition, our algorithm can be extended to handle design rules such as overlap margin and minimum width for practical use as well as off-grid layout. Our approach can reduce 33% of stitches and remove conflicts by 87.6% compared with two phase greedy decomposition.
Wave Tunneling and Hysteresis in Nonlinear Junctions

We consider the nonlinear tunneling of a plane wave through a small barrier potential in a medium with self-defocusing, or repulsive, interactions. We show that nonlinearity can either suppress or enhance transmission rates, determined by whether the initial kinetic energy is above or below the barrier height. Associated with this threshold is the appearance of two distinct hysteresis loops, going clockwise or counterclockwise, respectively. Spatial dynamics upon reflection and transmission reveals the formation of dispersive shock waves (dark soliton trains) due to phase jumps at the interfaces and wave steepening during propagation. The results are demonstrated experimentally for optical wave tunneling through a refractive index defect but will hold for any Schrodinger system that contains a nonlinear junction.
EARTH'S CRYOSPHERE: Current State and Recent Changes

The Earth continues to have a third of the ice that it had at the peak of the last ice age, although that ice continues to decrease, as it has, overall, for the past 18,000 years. Over the last 100 years, the retreat signal has been especially strong in ice shelves of the Arctic and along the Antarctic Peninsula, with a more mixed signal elsewhere. For instance, since the early 1990s the massive Greenland and Antarctic ice sheets have thinned along the coasts but thickened in the interior, and since the late 1970s sea ice has decreased in the Arctic but increased (slightly) in the Antarctic. Major difficulties in the interpretations of the climate record come from the high interannual variability of most cryosphere components and the lack of consistent long-term global data records, the latter problem now being slowly remedied, in part, through satellite technology.
A Procedure for Verifying the Structural Integrity of an Existing Pressurized Wind Tunnel

The present work describes the approach employed in verifying the structural integrity at maximum operating pressure of a low turbulence pressurized wind tunnel built in 1939-1940. The approach utilized existing ASME Code guidelines and fracture mechanics techniques in combination with the latest nondestructive examination methods to validate the desired life of the facility while minimizing reconstruction or major modifications. Detailed stress analyses using a finite element computer program and a numerical integration program were performed on critical areas of the tunnel. Critical vessel areas were evaluated for remaining fatigue life. Fracture mechanics analyses of the shell were performed at various regions, and critical flaw sizes at each location were determined. Analysis of the test data permitted the remaining useful life of the tunnel to be estimated at 8 to 10 years.
Physics of Strongly coupled Quark-Gluon Plasma

This review cover our current understanding of strongly coupled Quark-Gluon Plasma (sQGP), especially theoretical progress in (i) explaining the RHIC data by hydrodynamics, (ii) describing lattice data using electric-magnetic duality; (iii) understanding of gauge-string duality known as AdS/CFT and its application for \conformal" plasma. In view of interdisciplinary nature of the subject, we include brief introduction into several topics \for pedestrians". Some fundamental questions addressed are: Why is sQGP such a good liquid? What is the nature of (de)connement and what do we know about \magnetic" objects creating it? Do they play any important role in sQGP physics? Can we understand the AdS/CFT predictions, from the gauge theory side? Can they be tested experimentally? Can AdS/CFT duality help us understand rapid equilibration/entropy production? Can we work out a complete dynamical \gravity dual" to heavy ion collisions?
Gauge theory and wild ramification

The gauge theory approach to the geometric Langlands program is extended to the case of wild ramification. The new ingredients that are required, relative to the tamely ramified case, are differential operators with irregular singularities, Stokes phenomena, isomonodromic deformation, and, from a physical point of view, new surface operators associated with higher order singularities.
Existence of Equilibrium in Single and Double Private Value Auctions

We show existence of equilibria in distributional strategies for a wide class of private value auctions, including the first general existence result for double auctions. The set of equilibria is invariant to the tie-breaking rule. The model incorporates multiple unit demands, all standard pricing rules, reserve prices, entry costs, and stochastic demand and supply. Valuations can be correlated and asymmetrically distributed. For double auctions, we show further that at least one equilibrium involves a positive volume of trade. The existence proof establishes new connections among existence techniques for discontinuous Bayesian games.
TWO JOVIAN-MASS PLANETS IN EARTHLIKE ORBITS

We report the discovery of two new planets: a 1.94 M_(Jup) planet in a 1.8 yr orbit of HD 5319, and a 2.51 M_(Jup) planet in a 1.1 yr orbit of HD 75898. The measured eccentricities are 0.12 for HD 5319b and 0.10 for HD 75898b, and Markov chain Monte Carlo simulations based on the derived orbital parameters indicate that the radial velocities of both stars are consistent with circular planet orbits. With low eccentricity and 1 AU < α < 2 AU, our new planets have orbits similar to terrestrial planets in the solar system. The radial velocity residuals of both stars have significant trends, likely arising from substellar or low-mass stellar companions.
Are mental properties supervenient on brain properties

The “mind-brain supervenience” conjecture suggests that all mental properties are derived from the physical properties of the brain. To address the question of whether the mind supervenes on the brain, we frame a supervenience hypothesis in rigorous statistical terms. Specifically, we propose a modified version of supervenience (called e-supervenience) that is amenable to experimental investigation and statistical analysis. To illustrate this approach, we perform a thought experiment that illustrates how the probabilistic theory of pattern recognition can be used to make a one-sided determination of e-supervenience. The physical property of the brain employed in this analysis is the graph describing brain connectivity (i.e., the brain-graph or connectome). e-supervenience allows us to determine whether a particular mental property can be inferred from one's connectome to within any given positive misclassification rate, regardless of the relationship between the two. This may provide further motivation for cross-disciplinary research between neuroscientists and statisticians.
Multimedia conferencing: has it come of age?

Multimedia conferencing continues to be an active research area with a diversity of systems being developed for a variety of situations. In particular, multimedia conferencing is central to the idea of the collaboratory, an electronic environment for conducting science. As a vehicle for telecollaboration, multimedia conferencing promises to provide a meeting place for those needing to work cooperatively from afar. The paper reviews current research projects in telecollaboration. The authors frame the discussion of multimedia conferencing with a nomenclature and taxonomy. They compare local versus remote conferencing, touching on issues in system architecture and network communication requirements. They examine the recurring problems researchers have observed and the solutions they have chosen. With the advent of new technologies and with a growing sensitivity to human factors, if multimedia conferencing has not already come of age, it now has the opportunity. >
An AIS-ACO hybrid approach for multi-objective distribution system reconfiguration

Abstract form only given. This paper proposes a hybrid algorithm based on artificial immune systems and ant colony optimization for distribution system reconfiguration, which is formulated as a multi-objective optimization problem. The algorithm maintains a population of candidate solutions called antibodies. The search space is explored by means of the hypermutation operator that perturbs existing antibodies to produce new ones. A table of pheromones is used to reinforce better edges during hypermutation. An added innovation is the use of the pheromones to obtain quick solutions to restore the distribution system under contingency situations. The hybrid approach has been successfully implemented on two test networks. The results obtained demonstrate the efficacy of the algorithm.