cssi/SciSciGPT-SciSciNet huggingface dataset:
PHYSICS OPPORTUNITIES WITH A TEV LINEAR COLLIDER

▪ Abstract We discuss the physics motivations for building a 500 GeV–1 TeV electron-positron linear collider. The state-of-the-art collider technologies and the physics-driven machine parameters are discussed. Some of the phenomena well suited to study at a linear collider are described, including Higgs bosons, supersymmetry, other extensions to the standard model, and cosmology.
The Direct Relevance of Accounting Information for Credit Default Swap Pricing

Abstract: This paper examines the direct relevance of accounting information for credit default swap (CDS) pricing. Prior research on the impact of accounting information for CDS pricing has neglected to include either the output of theoretical CDS pricing models or credit ratings, both of which should impound credit relevant accounting information. Both in- and out-of-sample testing results suggest that accounting information's explanatory power for CDS prices is significantly diminished when this additional information is included in regression models. Empirical findings suggest a larger indirect role for accounting information in pricing CDS’, which play an important role in credit risk price discovery.
Health insurance as a two-part pricing contract

Monopolies appear throughout health care. We show that health insurance operates like a conventional two-part pricing contract that allows monopolists to extract profits without inefficiently constraining quantity. When insurers are free to offer a range of insurance contracts to different consumer types, health insurance markets perfectly eliminate deadweight losses from upstream health care monopolies. Frictions limiting the sorting of different consumer types into different insurance contracts restore some of these upstream monopoly losses, which manifest as higher rates of uninsurance, rather than as restrictions in quantity utilized by insured consumers. Empirical analysis of pharmaceutical patent expiration supports the prediction that heavily insured markets experience little or no efficiency loss under monopoly, while less insured markets exhibit behavior more consistent with the standard theory of monopoly.
Synthesis of bicyclic tetrahydrofurans from linear precursors using manganese(III) acetate

We have recently developed methodology based on oxidative radical reactions for the synthesis of [3.3.0]-bicyclic lactones containing both cyclopentanes and γ-lactams along with application of this methodology to the synthesis of natural products and complex molecular architectures. Herein we report an extension of this methodology to the synthesis of oxygen heterocycles including bicyclic bis-lactones.
Solar photovoltaic charging of lithium-ion batteries

Solar photovoltaic (PV) charging of batteries was tested by using high efficiency crystalline and amorphous silicon PV modules to recharge lithium-ion battery modules. This testing was performed as a proof of concept for solar PV charging of batteries for electrically powered vehicles. The iron phosphate type lithium-ion batteries were safely charged to their maximum capacity and the thermal hazards associated with overcharging were avoided by the self-regulating design of the solar charging system. The solar energy to battery charge conversion efficiency reached 14.5%, including a PV system efficiency of nearly 15%, and a battery charging efficiency of approximately 100%. This high system efficiency was achieved by directly charging the battery from the PV system with no intervening electronics, and matching the PV maximum power point voltage to the battery charging voltage at the desired maximum state of charge for the battery. It is envisioned that individual homeowners could charge electric and extended-range electric vehicles from residential, roof-mounted solar arrays, and thus power their daily commuting with clean, renewable solar energy.
An Education in Distance Learning: The Case of Agribusiness 101

A Cal Poly introductory agribusiness class is taught via distance education to a Southern California junior college as part of a pilot project of a USDA grant to increase diversity in agribusiness education. Live, interactive video presents new challenges to on-campus students, distant students and the instructor.
Detection filter design: Spectral theory and algorithms

A new formulation of the detection filter problem is generated by assignment of the closed-loop eigenstructure under certain constraints. Detection filters, which are actually a specific class of observers, fix the output error direction of the system so that it can be associated with a particular failure mode and its known design failure direction. The derivation of detection filters from an eigensystem assignment approach permits a very transparent theory. The detection filter gains and closed-loop eigenvectors are obtained from a set of simultaneous equations. Necessary and sufficient conditions for the solution of these algebraic equations are determined which produce a complete theory for detection filters.
Impact of Entry and Exit on Agribusiness-Trucking Industry Efficiency: Stochastic Frontier Analysis

In this paper, the impact of entry and exit of firms on the overall efficiency of the industry is examined in the efficiency framework, using agribusiness-trucking firms for the period 1994-2003. Specifically, industry efficiency is compared with and without firms that enter and exit using panel stochastic frontier analysis.
High Angular Resolution Integral-Field Spectroscopy of the Galaxy's Nuclear Cluster: A Missing Stellar Cusp?

We report on the structure of the nuclear star cluster in the innermost 0.16 pc of the Galaxy as measured by the number density profile of late-type giants. Using laser guide star adaptive optics in conjunction with the integral field spectrograph, OSIRIS, at the Keck II telescope, we are able to differentiate between the older, late-type (~1 Gyr) stars, which are presumed to be dynamically relaxed, and the unrelaxed young (~6 Myr) population. This distinction is crucial for testing models of stellar cusp formation in the vicinity of a black hole, as the models assume that the cusp stars are in dynamical equilibrium in the black hole potential. In the survey region, we classified 60 stars as early-type (22 newly identified) and 74 stars as late-type (61 newly identified). We find that contamination from young stars is significant, with more than twice as many young stars as old stars in our sensitivity range (K' < 15.5) within the central arcsecond. Based on the late-type stars alone, the surface stellar number density profile, Σ(R)∝ R^(–Γ), is flat, with Γ = -0.27 ± 0.19. Monte Carlo simulations of the possible de-projected volume density profile, n(r)∝ r^(–γ), show that γ is less than 1.0 at the 99.7% confidence level. These results are consistent with the nuclear star cluster having no cusp, with a core profile that is significantly flatter than that predicted by most cusp formation theories, and even allows for the presence of a central hole in the stellar distribution. Of the possible dynamical interactions that can lead to the depletion of the red giants observable in this survey—stellar collisions, mass segregation from stellar remnants, or a recent merger event—mass segregation is the only one that can be ruled out as the dominant depletion mechanism. The lack of a stellar cusp around a supermassive black hole would have important implications for black hole growth models and inferences on the presence of a black hole based upon stellar distributions.
Systematic methods for knowledge acquisition and expert system development

Nine cooperating rule-based systems, collectively called AUTOCREW, were designed to automate functions and decisions associated with a combat aircraft's subsystems. Performance metrics were developed to evaluate the workload of each rule base and to assess the cooperation between the rule bases. Each AUTOCREW subsystem is composed of several expert systems that perform specific tasks. The NAVIGATOR determines optimal navigation strategies from a set of available sensors. A navigation sensor management (NSM) expert system was systematically designed from Kalman filter covariance data: the NSM Expert was developed by means of the analysis-of-variance (ANOVA) and ID3 algorithm. Navigation strategy selection is based on a root-sum-of-squares position error decision metric computed from the covariance data. Results show that the NSM Expert predicts position error correctly between 45% and 100% of the time for a specified navaid configuration and aircraft trajectory. The NSM Expert adapts to new situations and provides reasonable estimates of hybrid performance. >
Distinguishing direct versus indirect transcription Factor-DNA interactions

Transcriptional regulation is largely enacted by transcription factors (TFs) binding DNA Large numbers of TF binding motifs have been revealed by ChIP-chip experiments followed by computational DNA motif discovery However, the success of motif discovery algorithms has been limited when applied to sequences bound in vivo (such as those identified by ChIP-chip) because the observed TF-DNA interactions are not necessarily direct: some TFs predominantly associate with DNA indirectly through protein partners, while others exhibit both direct and indirect binding. We present the first method for distinguishing between direct and indirect TF-DNA interactions, integrating in vivo TF binding data, in vivo nucleosome occupancy data, and DNA binding motifs from in vitro protein binding microarray experiments When applied to yeast ChIP-chip data, our method reveals that only 48% of the data sets can be readily explained by direct binding of the profiled TF, while 16% can be explained by indirect DNA binding In the remaining 36%, none of the motifs used in our analysis was able to explain the ChIP-chip data, either because the data were too noisy or because the set of motifs was incomplete As more in vitro TF DNA binding motifs become available, our method could be used to build a complete catalog of direct and indirect TF-DNA interactions Our method is not restricted to yeast or to ChIP-chip data, but can be applied in any system for which both in vivo binding data and in vitro DNA binding motifs are available.
White-Noise and Geometrical Optics Limits of Wigner-Moyal Equation for Wave Beams in Turbulent Media

Starting with the Wigner distribution formulation for beam wave propagation in Holder continuous non-Gaussian random refractive index fields we show that the wave beam regime naturally leads to the white-noise scaling limit and converges to a Gaussian white-noise model which is characterized by the martingale problem associated to a stochastic differential-integral equation of the Ito type. In the simultaneous geometrical optics the convergence to the Gaussian white-noise model for the Liouville equation is also established if the ultraviolet cutoff or the Fresnel number vanishes sufficiently slowly. The advantage of the Gaussian white-noise model is that its n-point correlation functions are governed by closed form equations.
GEODYNAMICS AND RATE OF VOLCANISM ON MASSIVE EARTH-LIKE PLANETS

We provide estimates of volcanism versus time for planets with Earth-like composition and masses 0.25–25 M⊕, as a step toward predicting atmospheric mass on extrasolar rocky planets. Volcanism requires melting of the silicate mantle. We use a thermal evolution model, calibrated against Earth, in combination with standard melting models, to explore the dependence of convection-driven decompression mantle melting on planet mass. We show that (1) volcanism is likely to proceed on massive planets with plate tectonics over the main-sequence lifetime of the parent star; (2) crustal thickness (and melting rate normalized to planet mass) is weakly dependent on planet mass; (3) stagnant lid planets live fast (they have higher rates of melting than their plate tectonic counterparts early in their thermal evolution), but die young (melting shuts down after a few Gyr); (4) plate tectonics may not operate on high-mass planets because of the production of buoyant crust which is difficult to subduct; and (5) melting is necessary but insufficient for efficient volcanic degassing—volatiles partition into the earliest, deepest melts, which may be denser than the residue and sink to the base of the mantle on young, massive planets. Magma must also crystallize at or near the surface, and the pressure of overlying volatiles must be fairly low, if volatiles are to reach the surface. If volcanism is detected in the 10 Gyrold τ Ceti system, and tidal forcing can be shown to be weak, this would be evidence for plate tectonics.
Silicon-on-sapphire complementary MOS circuits for high speed associative memory

The utility of associative memory in a wide variety of information handling systems has been long recognized and in the early 1950's such memory systems were proposed for implementation through cryotron logic and storage arrays. Cryogenic element technology afforded the ingredient of compatible logic and memory within a basic cell, a requirement essential to the practical realization of associative memories. To date, such an approach has not been successful due mainly to processing difficulties connected with thin film elements operating in a liquid helium environment. Other approaches, involving the use of multi-apertured magnetic elements, have been proposed and implemented, but the resultant cost was prohibitive due to complexities of peripheral electronics as well as the magnetic storage element itself. Furthermore, systems of this type have relatively long parallel search times (~ 10 μsecs) especially if access is on a serial-by-bit basis. These considerations have seriously limited the applicability of associative concepts in all forms of data processing and have resulted in a situation where system designers do not consider associative memory as a solution to a given problem in spite of many obvious advantages in applications such as sorting, merging, pattern recognition, and most recently, memory allocation in time shared computers.
Combined Effects of Metal and Ligand Capable of Accepting a Proton or Hydrogen Bond Catalyze Anti‐Markovnikov Hydration of Terminal Alkynes

A binding pocket for water is created in 1 by the imidazolyl phosphane ligands and the RuII center. Compound 1 proves to be an excellent catalyst for a highly selective anti-Markovnikov hydration of terminal alkynes to give aldehydes rather than isomeric ketones under near-neutral conditions (aldehyde-to-ketone ratio up to 1000:1).
A memory access model for highly-threaded many-core architectures

A number of highly-threaded, many-core architectures hide memory-access latency by low-overhead context switching among a large number of threads. The speedup of a program on these machines depends on how well the latency is hidden. If the number of threads were infinite, theoretically, these machines could provide the performance predicted by the PRAM analysis of these programs. However, the number of threads per processor is not infinite, and is constrained by both hardware and algorithmic limits. In this paper, we introduce the Threaded Many-core Memory (TMM) model which is meant to capture the important characteristics of these highly-threaded, many-core machines. Since we model some important machine parameters of these machines, we expect analysis under this model to provide a more fine-grained and accurate performance prediction than the PRAM analysis. We analyze 4 algorithms for the classic all pairs shortest paths problem under this model. We find that even when two algorithms have the same PRAM performance, our model predicts different performance for some settings of machine parameters. For example, for dense graphs, the dynamic programming algorithm and Johnson's algorithm have the same performance in the PRAM model. However, our model predicts different performance for large enough memory-access latency and validates the intuition that the dynamic programming algorithm performs better on these machines. We validate several predictions made by our model using empirical measurements on an instantiation of a highly-threaded, many-core machine, namely the NVIDIA GTX?480. We design a memory model to analyze algorithms for highly-threaded many-core systems.The model captures significant factors of performance: work, span, and memory accesses.We show the model is better than PRAM by applying both to 4 shortest paths algorithms.Empirical performance is effectively predicted by our model in many circumstances.It is the first formalized asymptotic model helpful for algorithm design on many-cores.
Econometrics of Fair Values

The properties of many important valuation rules can be quantified, examined, and compared in a unified framework to assist policy decisions. Valuation rules can be viewed as econometric estimators of unobserved values of aggregates. Which valuation rule has minimum mean squared error (relative to the unobserved value of bundles of resources) is a matter of econometrics, not of theory or principle; it depends in a known fashion on the relative magnitudes of the parameters—price volatility and measurement errors—of the economy, industry, or firm. In general, no valuation rule, fair or not, dominates the others. Given the parameters of an environment, this framework can help identify efficient valuation rules.
Understanding the AMT, and Its Unadopted Sibling, the AMxT

Four million Americans with extensive tax preferences are subject to the Alternative Minimum Tax (AMT). By taxing a broad definition of income, the AMT makes it possible to have a tax system that both encourages certain activities with generous tax preferences and maintains a semblance of distributional equity. The same rationale supports the imposition of an Alternative Maximum Tax (AMxT), which would cap tax liabilities of individuals with very few preference items and thereby afford Congress greater flexibility in designing the income tax. The original 1969 AMT proposal included an AMxT; it is difficult to justify imposing one without the other.
Thorstein Veblen: A Marxist Starting Point

As the radical institutionalist literature attests, in spite of methodological differences Marx and Veblen draw strikingly similar conclusions regarding production, conflict, and alienation in modern life. Here we attempt to contribute to this viewpoint by establishing that similarity in conclusion stems from similarity in approach. After reviewing the existing literature on a Marx-Veblen methodological reconciliation, we briefly review Marx's method, making the mediated starting point the focus of discussion. From this vantage point, we then examine Veblen's own approach to analysis in The Theory of Business Enterprise and the conclusions that emerge as they resemble those of Marx. We maintain that in taking a kindred approach Veblen is able to arrive at an understanding of capitalism in accordance with, and complementary to, Marx's rendering of the inverted nature of economic life in modernity.
Incremental Maintenance of Software Artifacts

Software is multidimensional, but the tools that support it are not. This lack of tool support causes the software artifacts representing different dimensions to evolve independently and to become inconsistent over time. In order to properly support the evolution of software, one must ensure that the different dimensions evolve concurrently. We have built a software development tool, CLIME that uses constraints implemented as database queries to ensure just this. Our approach makes the tool responsible for detecting inconsistencies between software design, specifications, documentation, source code, test cases, and other artifacts without requiring any of these to be a primary representation. The tool works incrementally as the software evolves, without imposing a particular methodology or process. It includes a front end that lets the user explore and fix current inconsistencies. This paper describes the basis for CLIME, the techniques underlying the tool, the interface provided to the programmer, the incremental maintenance of constraints between these artifacts, and our experiences
Generalization of the Fortuin-Kasteleyn transformation and its application to quantum spin simulations

We generalize the Fortuin-Kasteleyn (FK) cluster representation of the partition function of the Ising model to represent the partition function of quantum spin models with an arbitrary spin magnitude in arbitrary dimensions. This generalized representation enables us to develop a new cluster algorithm for the simulation of quantum spin systems by the worldline Monte Carlo method. Because the Swendsen-Wang algorithm is based on the FK representation, the new cluster algorithm naturally includes it as a special case. As well as the general description of the new representation, we present an illustration of our new algorithm for some special interesting cases: the Ising model, the antiferromagnetic Heisenberg model withS=1, and a general Heisenberg model. The new algorithm is applicable to models with any range of the exchange interaction, any lattice geometry, and any dimensions.
The Effectiveness of Court Connected Dispute Resolution in Civil Cases

This article reviews the empirical research on mediation and neutral evaluation, two court-connected dispute resolution processes in which the third party does not have decision-making power. Mediation has been used in small claims cases, general jurisdiction trial cases, and appellate cases; neutral evaluation has been used primarily in general jurisdiction cases. Because the program structure and the nature of the mediation process differ across the three court levels, the research findings are presented separately for each type of court as well as for each dispute resolution process. I review the data sources and methodology used in the studies examined here, describe the dispute resolution process and the structure of the programs in order to provide a context for interpreting the research, present the empirical findings regarding program outcomes, and report findings regarding the impact of program structure on outcomes. 1
Accuracy of a third (Dolphin Voyager) versus first generation pulse oximeter (Nellcor N-180) in predicting arterial oxygen saturation and pulse rate in the anesthetized dog.

Abstract Objective To compare the accuracy of a 3rd ( Dolphin Voyager ) versus 1st generation pulse oximeter ( Nellcor N-180 ). Study design Prospective laboratory investigation. Animals Eight adult dogs. Methods In anesthetized dogs, arterial oxygen saturation (SpO 2 ) was recorded simultaneously with each pulse oximeter. The oxygen fraction in inspired gas (FiO 2 ) was successively reduced from 1.00 to 0.09, with re-saturation (FiO 2 0.40) after each breathe-down step. After each 3-minute FiO 2 plateau, SpO 2 and pulse rate (PR) were compared with the fractional arterial saturation (SaO 2 ) and PR determined by co-oximetry and invasive blood pressure monitoring, respectively. Data analysis included Bland-Altman (B–A) plots, Lin's concordance correlation factor (ρ c ), and linear regression models. Results Over a SaO 2 range of 33–99%, the overall bias (mean SpO 2 − SaO 2 ), precision (SD of bias), and accuracy ( A rms ) for the Dolphin Voyager and Nellcor N-180 were 4.3%, 4.4%, and 6.1%, and 3.2%, 3.0%, and 4.3%, respectively. Bias increased at SaO 2 Dolphin Voyager (from 1.6% to 8.6%) than Nellcor N-180 (from 3.2% to 4.5%). The SpO 2 readings correlated significantly with SaO 2 for both the Dolphin Voyager (ρ c = 0.94) and Nellcor N-180 (ρ c = 0.97) ( p A rms ) for the Dolphin Voyager and Nellcor N-180 were −0.5, 4.6, and 4.6 and 1.38, 4.3, and 4.5 beats minute −1 , respectively. Significant correlation existed between pulse oximeter and directly measured PR ( Dolphin Voyager : ρ c = 0.98; Nellcor N-180 : ρ c = 0.99) ( p Conclusions and clinical relevance In anesthetized dogs with adequate hemodynamic function, both instruments record SaO 2 relatively accurately over a wide range of normal saturation values. However, there is an increasing overestimation at SaO 2 Dolphin Voyager , indicating that 3rd generation pulse oximeters may not perform better than older instruments. The 5.4-fold increase in bias with the Dolphin Voyager at SaO 2 2 threshold to ensure an arterial saturation of ≥90%. In contrast, PR monitoring with both devices is very reliable.
Measuring recreation benefits of quality improvements with revealed and stated behavior data

We propose a combined revealed and stated behavior estimation method to measure recreation benefits of a fixed quality improvement that directly addresses the issues of variation in environmental quality beyond the observed range and new participation induced by higher quality. We survey a sample of the general population, including non-participants, to obtain stated preference data for trips based on a policy-relevant estuarine quality improvement. Panel recreation demand models that take into account new participants induced by the higher quality are estimated and used to derive total consumer surplus.
Synchronization of a magnetic computer

In computer design the problem of communication between the central computer and the outside world is always present. This paper describes how this problem was solved for the Cambridge computer with a new type of shift register employing the Ferractor*, the magnetic core developed by Remington Rand Univac. The computer and the magnetic amplifiers which it uses were described in some detail in other papers. The shift register itself has many unique features, however, and the design and application merit a separate discussion.
Pointwise bounds on quasimodes of semiclassical Schrödinger operators in dimension two

We prove optimal pointwise bounds on quasimodes of semiclassical Schrodinger operators with arbitrary smooth real potentials in dimension two. This end-point estimate was left open in the general study of semiclassical L bounds conducted by Koch-TataruZworski [2]. However, we show that the results of [2] imply the two dimensional end-point estimate by scaling and localization.
Financial Asset Holdings and Political Attitudes: Evidence from Revolutionary England*

The English Parliament’s struggle for supremacy against monarchical dictatorship during the Civil War (1642–1648) was crucial for the establishment of representative government, yet its lessons continue to be debated. I exploit novel data on individual MPs drawn from 1,842 biographies to show that the conflict was over overseas interests and other factors over which the executive enjoyed broad constitutional discretion, rather than over domestic property rights. I further exploit the coincidence of individual MPs’ ability to sign legally binding share contracts with novel share offerings by overseas companies to measure the effect of overseas share investment on their political attitudes. I show that overseas shareholding pushed moderates lacking prior mercantile interests to support reform. I interpret the effect of financial assetholding as allowing new investors to exploit emerging economic opportunities overseas, aligning their interests with traders. By consolidating a broad parliamentary majority that favored reform, the introduction of financial assets also broadened support for the institutionalization of parliamentary supremacy over dictatorial rule. JEL Codes: O10, G11, F10, K00, N23, P10.
Unilateral rectus muscle recession in the treatment of Duane syndrome.

Purpose To determine the outcome of unilateral single horizontal rectus recession surgery in patients with Duane retraction syndrome. Methods A retrospective review was conducted of 27 medical records of patients with Duane syndrome who underwent unilateral medial rectus recession for esodeviations and lateral rectus recession for exodeviations. The criteria for evaluating surgical success included improvement of abnormal head position, reduction of strabismus deviation, and preservation or improvement of stereoacuity. Results Patients had an average recession of 6.3 mm and were followed for an average of 4 years. Of the 27 patients treated with unilateral horizontal rectus muscle recession, 93% had a postoperative head turn of Conclusions Unilateral single horizontal rectus muscle recession improves or eliminates head turn, corrects strabismus in primary position of gaze, and maintains good stereoacuity in a majority of patients with Duane syndrome.
Establishing lower bounds on algorithms: a survey

Algorithms for various computations have been known and studied for centuries, but it is only recently that much theoretical attention has been devoted to the analysis of algorithms. Turing machines and recursive functions were the first approaches, but these models, which provide much interesting mathematics, do not look at the problem from a practical standpoint. In "real" computing, no one uses Turing machines to evaluate polynomials or to multiply matrices, and little of practical significance is obtained from that approach. On the other hand, recent work has led to more realistic models and, correspondingly, to more practical results. Most of the results cannot be considered to be truly practical, but, all of them were motivated by practical considerations.
Design and verify: a new scheme for generating cutting-planes

A cutting-plane procedure for integer programming (IP) problems usually involves invoking a black-box procedure (such as the Gomory–Chvatal procedure) to compute a cutting-plane. In this paper, we describe an alternative paradigm of using the same cutting-plane black-box. This involves two steps. In the first step, we design an inequality $$cx \le d$$ where $$c$$ and $$d$$ are integral, independent of the cutting-plane black-box. In the second step, we verify that the designed inequality is a valid inequality by verifying that the set $$P \cap \{x\in \mathbb R ^n \mid cx \ge d + 1\} \cap \mathbb Z ^n$$ is empty using cutting-planes from the black-box. Here $$P$$ is the feasible region of the linear-programming relaxation of the IP. We refer to the closure of all cutting-planes that can be verified to be valid using a specific cutting-plane black-box as the verification closure of the considered cutting-plane black-box. This paper undertakes a systematic study of properties of verification closures of various cutting-plane black-box procedures.
Paracrystallinity-modulus relationships in kevlar aramid fibers

Abstract Meridional x-ray reflections of Kevlar (TM) aramid fibers have been analyzed to provide direct information about fine structure in the direction of the fiber axis. In particular, these reflections have been studied to provide evidence for a one-dimensional paracrystalline structure in Kevlar and to seek quantitative structure-property relationships based on a paracrystalline structure model. In a series of Kevlar fibers an excellent correlation is found between paracrystalline distortion factor gII and tensile modulus, with gII decreasing from 2.33% to 1.69% as modulus increases from 75 GPa to 125 GPa. Surprisingly, however, there is no systematic increase in axial crystallite length within this series in spite of heat treatment.
Gating of neural error signals during motor learning.

Cerebellar climbing fiber activity encodes performance errors during many motor learning tasks, but the role of these error signals in learning has been controversial. We compared two motor learning paradigms that elicited equally robust putative error signals in the same climbing fibers: learned increases and decreases in the gain of the vestibulo-ocular reflex (VOR). During VOR-increase training, climbing fiber activity on one trial predicted changes in cerebellar output on the next trial, and optogenetic activation of climbing fibers to mimic their encoding of performance errors was sufficient to implant a motor memory. In contrast, during VOR-decrease training, there was no trial-by-trial correlation between climbing fiber activity and changes in cerebellar output, and climbing fiber activation did not induce VOR-decrease learning. Our data suggest that the ability of climbing fibers to induce plasticity can be dynamically gated in vivo, even under conditions where climbing fibers are robustly activated by performance errors. DOI: http://dx.doi.org/10.7554/eLife.02076.001
Institutional Changes Affecting Entrepreneurship in China

Institutions influencing entrepreneurship are undergoing significant transformation in China. During the Mao era, private entrepreneurship was virtually eradicated and was a political taboo. As reflected in the macro-level economic data, there has been an evolution of entrepreneur-friendly institutions in the country. A constellation of factors linked to China‘s global integration is pushing through fundamental changes in institutions related to Chinese entrepreneurship. The logics or governance structures and organizing principles related to entrepreneurship are rapidly changing in the country. This paper examines forces influencing the diffusion of instrumental values promoting entrepreneurship among Chinese institutional actors.
Performance-Sensitive Debt

This paper studies performance-sensitive debt (PSD), the class of debt obligations whose interest payments depend on some measure of the borrower’s performance. We demonstrate that the existence of PSD obligations cannot be explained by the trade-off theory of capital structure, as PSD leads to earlier default and lower equity value compared to fixed-rate debt of the same market value. We show that, consistent with the pecking order theory, PSD can be used as an inexpensive screening device, and we find empirically that firms choosing PSD loans are more likely to improve their credit ratings than firms choosing fixed-interest loans. We also develop a method to value PSD obligations allowing for general payment profiles and obtain closed-form pricing formulas for step-up bonds and linear PSD.
Quantitative structure-activity relationship for cyclic imide derivatives of protoporphyrinogen oxidase inhibitors: a study of quantum chemical descriptors from density functional theory.

This study examined the applicability of various density functional theory (DFT)-based descriptors, such as energy gap (ΔE) between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), weighted nucleophilic atomic frontier electron density (WNAFED, ), mean molecular polarizability (α), and net atomic charge (Qi), in quantitative structure−activity relationship (QSAR) studies on a class of important protoporphyrinogen oxidase (Protox) inhibitors including a series of cyclic imide derivatives with various heterocyclic rings and substituents. Our QSAR analysis using the quantum chemical descriptors calculated at the B3LYP/6-31G(d,p) level led to a useful explicit correlation relationship, i.e. pI50 = −5.7414 + 0.1424α − 0.0003α2 − 0.4546 + 0.2974QN•• (n=26, R2=0.87), showing that descriptors mean molecular polarizability, α, and WNAFED of a critical carbon atom and net atomic charge (Qi) in the molecules are most likely responsible for the in vitro biological acti...
Why Do Some Countries Default More Often Than Others? The Role of Institutions

This paper examines how a country's weak institutions and polarized government can affect the likelihood of its default on sovereign debt. Using a data set of 90 countries, it shows that strong institutions are associated with fewer sovereign default crises. In addition, when institutions are weak, a more polarized government tends to default more often. To explain these findings, the author develops a model showing the dynamics between the quality of institutions, the level of government polarization and sovereign default risk. Countries default more often when they lack rules and strong institutions to curb the influence of powerful groups on government policies. That is because in a polarized government, each powerful group makes decisions without considering the impact on other groups. Simulations of the model show that more than half the cross-country variation in sovereign default frequencies can be explained by institutional quality and the degree of government polarization observed in the data.
Enhancements to a Lightweight RFID Authentication Protocol

This study extends the vulnerability analysis of a RFID authentication protocol and offers solutions to security weaknesses through enhanced measures. Vajda and Buttyan (VB) proposed a set of five lightweight RFID authentication protocols. Defend, Fu, and Juels (DFJ) did cryptanalysis on two of them - XOR and SUBSET. DFJ proposed repeated keys and nibble attacks on the XOR protocol. In this paper, we identify the source of vulnerability within VB's original successive session key permutation algorithm. We propose three enhancements - removing bad shuffles, hopping the runs, and authenticating mutually - to prevent DFJ's attacks, thereby significantly strengthening the XOR protocol without introducing extra resource cost.
Urbanization as opportunity

Urbanization deserves urgent attention from policy makers, academics, entrepreneurs, and social reformers of all stripes. Nothing else will create as many opportunities for social and economic progress. The urbanization project began roughly 1,000 years after the transition from the Pleistocene to the milder and more stable Holocene interglacial. In 2010, the urban population in developing countries stood at 2.5 billion. The developing world can accommodate the urban population growth and declining urban density in many ways. The most important citywide projects -- successes like New York and Shenzhen -- show even more clearly how influential human intention can be. The developing world can accommodate the urban population growth and declining urban density in many ways. One is to have a threefold increase in the average population of its existing cities and a six fold increase in their average built-out area. Another, which will leave the built-out area of existing cities unchanged, will be to develop 625 new cities of 10 million people -- 500 new cities to accommodate the net increase in the urban population and another 125 to accommodate the 1.25 billion people who will have to leave existing cities as average density falls by half.
Likelihood, probability, and knowledge

The modal logic LL was introduced by Halpern and Rabin as a means of doing qualitative reasoning about likelihood. Here the relationship between LL and probability theory is examined. It is shown that there is a way of translating probability assertions into LL in a sound manner, so that LL in some sense can capture the probabilistic interpretation of likelihood. However, the translation is subtle; several more obvious attempts are shown to lead to inconsistencies. We also extend LL by adding modal operators for knowledge. This allows us to reason about the interaction between knowledge and likelihood. The propositional version of the resulting logic LLK is shown to have a complete axiomatization and to be decidable in exponential time, provably the best possible. La logique modale LL a ete proposee par Halpern et Rabin comme moyen de proceder a un raisonnement qualitatif a propos de la vraisemblance. Dans cet article, la relation entre la logique modale LL et la theorie des probabilites est examinee. Les auteurs demontrent qu'il existe une facon de bien traduire des assertions probabilistiques en logique modale LL de facon a ce que cette derniere puisse saisir l'interpretation probabilistique de la vraisemblance. Cependant, cette traduction est subtile; plusieurs tentatives plus evidentes ont entraine des incoherences. Des operateurs modaux ont ete ajoutes a la logique modale LL afin de permettre un raisonnement sur l'interaction de la connaissance et de la vraisemblance. On a constate que la version propositionnelle de la logique resultante possedait une axiomatisation complete et s'averait un facteur decisif en temps exponentiel.
Toric fiber products

Abstract We introduce and study the toric fiber product of two ideals in polynomial rings that are homogeneous with respect to the same multigrading. Under the assumption that the set of degrees of the variables form a linearly independent set, we can explicitly describe generating sets and Grobner bases for these ideals. This allows us to unify and generalize some results in algebraic statistics.
Test Point Placement to Simplify Fault Detection

The problem of selecting test points to reduce the number of tests for fault detection in combinational logic networks is examined. A method is presented for labeling the lines of a network. Procedures are described for obtaining a minimal labeling, i.e., one corresponding to a minimal set of tests, for fanout-free circuits and for a restricted class of circuits with fanout. Using these procedures, a branch-and-bound algorithm is developed for selecting an optimal (or near-optimal) set of q test points in fanout-free networks. Some difficulties associated with test point placement in general networks are pointed out. It is shown that the labeling approach is also applicable to the problem of selecting and placing control logic.
Usage impact factor: The effects of sample characteristics on usage-based impact metrics

There exist ample demonstrations that indicators of scholarly impact analogous to the citation-based ISI Impact Factor can be derived from usage data; however, so far, usage can practically be recorded only at the level of distinct information services. This leads to community-specific assessments of scholarly impact that are difficult to generalize to the global scholarly community. In contrast, the ISI Impact Factor is based on citation data and thereby represents the global community of scholarly authors. The objective of this study is to examine the effects of community characteristics on assessments of scholarly impact from usage. We define a journal Usage Impact Factor that mimics the definition of the Thomson Scientific ISI Impact Factor. Usage Impact Factor rankings are calculated on the basis of a large-scale usage dataset recorded by the linking servers of the California State University system from 2003 to 2005. The resulting journal rankings are then compared to the Thomson Scientific ISI Impact Factor that is used as a reference indicator of general impact. Our results indicate that the particular scientific and demographic characteristics of a discipline have a strong effect on resulting usage-based assessments of scholarly impact. In particular, we observed that as the number of graduate students and faculty increases in a particular discipline, Usage Impact Factor rankings will converge more strongly with the ISI Impact Factor. © 2008 Wiley Periodicals, Inc.
Evaluating the crowd with confidence

Worker quality control is a crucial aspect of crowdsourcing systems; typically occupying a large fraction of the time and money invested on crowdsourcing. In this work, we devise techniques to generate confidence intervals for worker error rate estimates, thereby enabling a better evaluation of worker quality. We show that our techniques generate correct confidence intervals on a range of real-world datasets, and demonstrate wide applicability by using them to evict poorly performing workers, and provide confidence intervals on the accuracy of the answers.
A Highly Efficient and Broadly Applicable Cationic Gold Catalyst

Gold catalysts capable of promoting reactions at low-level loadings under mild conditions are the exception rather than the norm. We examined reactions where the regeneration of cationic gold catalyst (e.g., protodeauration) was the turnover limiting stage. By manipulating electron density on the substituents around phosphorus and introducing steric handles we designed a phosphine ligand that contains two electron-rich ortho-biphenyl groups and a cyclohexyl substituent. This ligand formed a gold complex that catalyzed common types of gold-catalyzed reactions including intra- and intermolecular XH (X=C, N, O) additions to alkynes and cycloisomerizations, with high turnover numbers at room temperature or slightly elevated temperatures (≤50 °C). Our new ligand can be prepared in one step from commercially available starting materials.
Development, modernization, and childbearing: the role of family sex composition.

Does the sex composition of existing children in a family affect fertility behavior? An unusually large data set, covering 64 countries and some 5 million births, is used to show that fertility behavior responds to the presence, or absence, of sons in many regions of the developing world. The response to the absence of sons is particularly large in Central Asia and South Asia. Modernization does not appear to reduce this differential response. For example, in South Asia the fertility response to the absence of sons is larger for women with more education and has been increasing over time. The explanation appears to be that a latent demand for sons is more likely to manifest itself when fertility levels are low. As a result of this differential fertility behavior, girls tend to grow up with significantly more siblings than do boys, with potential implications for their well-being when quantity, quality tradeoffs result in fewer material and emotional resources allocated to children in larger families.
Higher order correlations in computed particle distributions

The RMS emittances calculated for beam distributions using computer simulations are frequently dominated by higher-order aberrations. The possibility of defining higher-order correlations that can be removed from the distribution to result in a lower limit to the realizable emittance is explored. The purpose is to insert the correct combinations of linear lenses at the proper position so that the beam recombines in a way that cancels the effects of some higher-order forces. An example might be the nonlinear transverse space charge forces which cause a beam to spread. If the beam is then refocused so that the same nonlinear forces reverse the inward velocities, the resulting phase space distribution may reasonably approximate the original distribution. The motivation for this work comes from studies of a photocathode injector system for a linear accelerator intended to be used for a free-electron laser. >
Complexity through Recombination: From Chemistry to Biology

Recombination is a common event in nature, with examples in physics, chemistry, and biology. This process is characterized by the spontaneous reorganization of structural units to form new entities. Upon reorganization, the complexity of the overall system can change. In particular the components of the system can now experience a new response to externally applied selection criteria, such that the evolutionary trajectory of the system is altered. In this work we explore the link between chemical and biological forms of recombination. We estimate how the net system complexity changes, through analysis of RNA-RNA recombination and by mathematical modeling. Our results underscore the importance of recombination in the origins of life on the Earth and its subsequent evolutionary divergence.
An efficient virtual machine implementation

This paper describes the techniques used to implement an efficient virtual machine facility within MTS for the IBM System/360 Model 67. The goals of the project were to support the IBM Operating System, including the Indexed Sequential Access Method and Teleprocessing capabilities, as a subsystem under MTS with a maximum teleprocessing degradation of 30% for OS/360 programs and complete protection between OS/360 and MTS. The first attempt, using channel program relocation similar to that employed by CP-67, provided unacceptable response to teleprocessing requests which required indexed accesses to the data base. The second attempt obviated the need for most software relocation of channel programs by assuring that the OS/360 buffer areas and channel programs were allocated to main storage having addresses identical to their virtual addresses. Storage protection was accomplished by a hardware change to the IBM System/360 protection mechanism which created a two-level hierarchy of storage keys. Using these techniques the virtual machine met the goals of the project. The techniques employed are applicable to virtual memory systems other than MTS and the IBM System/360 Model 67