cssi/SciSciGPT-SciSciNet huggingface dataset:
Near-duplicate detection for eRulemaking

U.S. regulatory agencies are required to solicit, consider, and respond to public comments before issuing regulations. In recent years, agencies have begun to accept comments via both email and Web forms. The transition from paper to electronic comments makes it much easier for individuals to customize "form" letters, which they do, creating "near-duplicate" comments that express the same viewpoint in slightly different languages. This paper explores the use of simple text clustering and retrieval algorithms for identifying near-duplicate public comments. Experiments with public comments about a recent regulation proposed by the Environmental Protection Agency (EPA) demonstrate the effectiveness of the algorithms.
Performance verification and system parameter identification of spacecraft tape recorder control servo

NASA's 1976 Viking Mars Orbiters and the Voyager 1977 Jupiter-Saturn flyby spacecrafts carried digital tape recorders (DTR) on board. The recorders for both the missions were very similar except for the use of a brushless d.c. motor in the Voyager DTR. The mechanical part of the DTR consisted of fourteen rotating masses (tape reels, idlers and drive capstans) distributed in different planes and connected by three different elastic couplings (magnetic tape, peripheral belt and drive belts). Time simulations reported in this study were based on a program which employed first order integrators only. Severe numerical convergence problems were associated with the use of transfer function simulation subroutines available in the Continuous System Simulation Language (CSSL). The objective of this study is to verify the adequacy of design of the lead-lag compensator of the frequency loop, to check the accuracy of the analytical expression for the electrical motor transfer function (both arrived at empirically) and to understand in depth the performance of the speed control servo of the spacecraft DTR. Four aspects of the system dynamics were interactively adjusted to arrive at a number of stable system configurations, which had significantly different tape transport and/or compensator gain, DTR damping, system lag and electrical motor transfer function than envisioned in the nominal design by either the empirical or the linear frequency-domain methods.
Publicity of Debate and the Incentive to Dissent: Evidence from the US Federal Reserve

Transparency in committee decision making may have clear benefits by making members more accountable to outside observers. We consider one potential cost: the possibility that publishing records of deliberations will make members more reluctant to offer dissenting opinions. We construct a model that compares incentives for members with career concerns to voice dissent when deliberations occur in public or in private. We test the model using an original dataset based on deliberations of the Federal Reserve’s Federal Open Market Committee, asking whether the FOMC’s 1993 decision to begin releasing transcripts of its meetings has altered incentives for dissent. We find evidence that this is indeed the case. There has been much recent discussion of the advantages of transparency in agency relationships both in and outside of government. While research has attempted to model this issue theoretically, there has been less progress with empirical tests, a problem due no doubt in large part to the fact that it is difficult to make before and after comparisons of a shift in transparency. Often, no data are available on an agent’s actions prior to the establishment of transparency. In this article we focus on one specific type of transparency, publishing verbatim transcripts of committee meetings, and one specific reason why this type of transparency might not be desirable, the possibility that the quality of deliberation on a committee will suffer if the deliberations take place in public. We develop a theoretical model that helps to identify the potential costs of this type of transparency and we then test the model empirically using an original dataset on deliberations of the Federal Reserve’s Federal Open Market Committee (FOMC); our dataset is unique in that it records views expressed by policymakers at FOMC meetings and not just their official votes. Our empirical tests focus in particular on the observed effect of the institutional change that occurred in 1993, when the FOMC decided to begin releasing transcripts of its meetings after a delay of five years. Transparency is a particularly relevant issue in monetary policy, because it is commonly argued that when central banks take actions such as publishing macroeconomic forecasts, revealing individual votes on monetary policy committees, or releasing minutes of meetings, this will lead to improved economic outcomes while simultaneously facilitating democratic accountability. 1
Hydrologic Simulations of the Maquoketa River Watershed Using SWAT

This paper describes the application of the Soil and Water Assessment Tool (SWAT) model to the Maquoketa River watershed, located in northeast Iowa. The inputs to the model were obtained from the Environmental Protection Agency's geographic information/database system called Better Assessment Science Integrating Point and Nonpoint Sources (BASINS). Climatic data from six weather stations located in and around the watershed, and measured streamflow data from a U.S. Geological Survey gage station at the watershed outlet were used in the sensitivity analysis of SWAT model parameters as well as its calibration and validation for watershed hydrology and streamflow. A sensitivity analysis was performed using an influence coefficient method to evaluate surface runoff and baseflow variations in response to changes in model input hydrologic parameters. The curve number, evaporation compensation factor, and soil available water capacity were found to be the most sensitive parameters among eight selected parameters when applying SWAT to the Maquoketa River watershed. Model calibration, facilitated by the sensitivity analysis, was performed for the period 1988 through 1993, and validation was performed for 1982 through 1987. The model performance was evaluated by well-established statistical methods and was found to explain at least 86% and 69% of the variability in the measured streamflow data for the calibration and validation periods, respectively. This initial hydrologic modeling analysis will facilitate future applications of SWAT to the Maquoketa River watershed for various watershed analyses, including water quality.
Policies and patterns for high-performance, real-time object request brokers

Middleware is becoming increasingly important for building flexible communication systems that reduce software development cycle time and effort. Unfortunately, conventional middleware implementations of CORBA have historically lacked the efficiency, predictability, and scalability required by real-time systems. A decade of intensive R&D on design techniques and optimization principle patterns has recently converged, however, to yield high-performance and real-time middleware that can meet end-to-end Quality of Service (QoS) requirements for real-time systems. This tutorial outlines recent advances in real-time middleware, focusing on the policies and patterns in Real-time CORBA. Real-time CORBA defines a standard set of interfaces and capabilities to manage CPU, network, and memory resources predictably and efficiently end-to-end. This tutorial will illustrate via real world examples the key features and policies in the Real-time CORBA programming model. It will also describe the patterns that can be applied in ORB architectures to minimize priority inversion and non-determinism, associate client requests with servants in constant time, and implement standard and custom middleware protocols using small memory footprints. The patterns and optimizations covered in the tutorial are based on TAO, which is a widely used open-source real-time ORB that supports end-to-end QoS guarantees over a range of networks and embedded system interconnects. TAO is currently deployed at Boeing, Lockheed, Lucent, Motorola, Nokia, Nortel, Raytheon, SAIC, and Siemens, where it is used for real-time avionics, simulations, and telecommunications systems. Source code, documentation, and technical papers on TAO are available at www.cs.wustl.edu/~schmidt/TAO.html. Douglas Schmidt is an Associate Professor in the Electrical and Computer Engineering Department at the University of California, Irvine. Previously, he was Director of the Center for Distributed Object Computing and an Associate Professor of Department of Computer Science and the Department of Radiology at Washington University in St. Louis, Missouri, USA.His research focuses on design patterns, implementation, and experimental analysis of object-oriented frameworks that facilitate the development of high-performance, real-time distributed object computing systems on parallel processing platforms running over high-speed networks and embedded system interconnects. Proceedings of the Third International Symposium on Distributed-Objects and Applications (DOA’01) 0-7695-1300-X/01 $10.00 © 2001 IEEE Dr. Schmidt is an internationally recognized expert on distributed object computing and has published widely in top IEEE, ACM, IFIP, and USENIX technical conferences and journals on topics ranging from high-performance communication software systems and parallel processing for high-speed networking protocols to real-time distributed object computing with CORBA and object-oriented design patterns. Proceedings of the Third International Symposium on Distributed-Objects and Applications (DOA’01) 0-7695-1300-X/01 $10.00 © 2001 IEEE
Alliance “Capitalism” and Legal Education: An English Perspective

Elizabeth Chambliss’s analysis of developments in U.S. legal education is both comprehensive and instructive because of its critical perspective on the multi-dimensional changes currently under way as law schools increasingly collaborate with their “clients.”1 In this response Essay, my intention is not to question Chambliss’s analysis. Instead, I seek to compare the documented U.S. developments with some recent changes in the English context. I then reflect on the shared conundrums that exist as a result of what I describe—perhaps provocatively—as the forms of “alliance capitalism”2
Apartment Security: A Note on Gated Access and Rental Rates

The effect of gated access restrictions on garden apartment rents is empirically evaluated. Garden apartment rents are positively related to the presence of gated access constraints, although the c...
Punishment and Blame for Culpable Indifference

In criminal law, the mental state of the defendant is a crucial determinant of the grade of crime that the defendant has committed and of whether the conduct is criminal at all. Under the widely ac...
Krull Dimension of Monomial Ideals in Polynomial Rings with Real Exponents

We develop a new technique for studying monomial ideals in the standard polynomial rings A[X 1,…, X d ] where A is a commutative ring with identity. The main idea is to consider induced ideals in the semigroup ring where &#x1d544;1,…, &#x1d544; d are nonzero additive subgroups of ℝ. We prove that the set of nonzero finitely generated monomial ideals in R has the structure of a metric space, and we prove that a version of Krull dimension for this setting is lower semicontinuous with respect to this metric space structure. We also show how to use discrete techniques to study certain monomial ideals in this context.
Optimal trajectories in atmospheric flight

Aspects of optimization theory and switching theory are discussed, taking into account the necessary conditions for extrema, a solution subject to constraints, the calculus of variations, the Pontryagin maximum principle, the canonical transformation, Contensou's domain of maneuverability, optimal switching, a junction with singular arc, and linearized singular control. Equations of motion are considered along with aerodynamic and propulsive forces, the general properties of optimal trajectories, flight in a horizontal plane, optimal coasting flight, supersonic cruise, the supersonic turn, supersonic maneuvers in a vertical plane, energy state approximation, a modified Chapman's formulation for optimal reentry trajectories, optimal planar reentry trajectories, and an optimal glide of reentry vehicles. Orbital aerodynamic maneuvers are examined, giving attention to aerodynamic capture, a change in the apogee, a change in the eccentricity, a change in the perigee, an orbital maneuver, an aerodynamic maneuver, and a combined maneuver.
Frame-of-reference bias in subjective welfare regressions

Past research has found that subjective questions about an individuals'economic status do not correspond closely to measures of economic welfare based on household income or consumption. Survey respondents undoubtedly hold diverse ideas about what it means to be"poor"or"rich."Further, this heterogeneity may be correlated with other characteristics, including welfare, leading to frame-of-reference bias. To test for this bias, vignettes were added to a nationally representative survey of Tajikistan, in which survey respondents rank the economic status of the theoretical vignette households, as well as their own. The vignette rankings are used to reveal the respondent's own scale. The findings indicate that respondents hold diverse scales in assessing their welfare, but that there is little bias in either the economic gradient of subjective welfare or most other coefficients on covariates of interest. These results provide a firmer foundation for standard survey methods and regression specifications for subjective welfare data.
The grafting map of Teichmüller space

One of the underlying principles in the study of Kleinian groups is that aspects of the complex projective geometry of quotients of Ĉ by these groups reflect properties of the three-dimensional hyperbolic geometry of the quotients ofH by these groups. Yet, even though it has been over thirty-five years since Lipman Bers exhibited a holomorphic embedding of the Teichmuller space of Riemann surfaces in terms of the projective geometry of a Teichmuller space of quasi-Fuchsian manifolds, no corresponding embedding in terms of the three-dimensional hyperbolic geometry has been presented. One of the goals of this paper is to give such an embedding. This embedding is straightforward and has been expected for some time ([Ta97], [Mc98]): to each member of a Bers slice of the space QF of quasi-Fuchsian 3manifolds, we associate the bending measured lamination of the convex hull facing the fixed “conformal” end. The geometric relationship between a boundary component of a convex hull and the projective surface at infinity for its end is given by a process known as grafting, an operation on projective structures on surfaces that traces its roots back at least to Klein [Kl33, p. 230, §50], with a modern history developed by many authors ([Ma69], [He75], [Fa83], [ST83], [Go87], [GKM00], [Ta97], [Mc98]). The main technical tool in our proof that bending measures give coordinates for Bers slices, and the second major goal of this paper, is the completion of the proof of the “Grafting Conjecture”. This conjecture states that for a fixed measured lamination λ, the self-map of Teichmuller space induced by grafting a surface along λ is a homeomorphism of Teichmuller space; our contribution to this argument is a proof of the injectivity of the grafting map. While the principal application of this result that we give is to geometric coordinates on the Bers slice of QF , one expects that the grafting homeomorphism might lead to other systems of geometric coordinates for other families of Kleinian groups (see §5.2); thus we feel that this result is of interest in its own right. We now state our results and methods more precisely. Throughout, S will denote a fixed differentiable surface which is closed, orientable, and of genus g ≥ 2. Let Tg be the corresponding Teichmuller space of marked conformal structures on S, and let Pg denote the deformation space of (complex) projective structures on S (see §2 for definitions).
Bagging and boosting a treebank parser

Bagging and boosting, two effective machine learning techniques, are applied to natural language parsing. Experiments using these techniques with a trainable statistical parser are described. The best resulting system provides roughly as large of a gain in F-measure as doubling the corpus size. Error analysis of the result of the boosting technique reveals some inconsistent annotations in the Penn Treebank, suggesting a semi-automatic method for finding inconsistent treebank annotations.
Rotating Dilaton Solutions in 2+1 Dimensions

We report a three parameter family of solutions for dilaton gravity in 2+1 dimensions with finite mass and finite angular momentum. These solutions are obtained by a compactification of vacuum solutions in 3+1 dimensions with cylindrical symmetry. One class of solutions corresponds to conical singularities and the other leads to curvature singularities.
Gamma-Ray Bursts: Where are We Now?

There has been significant progress recently in our understanding of gamma-ray bursts. The long-sought counterparts at other wavelengths have finally been found for a few bursts. This breakthrough is the result of coordinated observations involving several satellites and ground-based optical and radio observatories. In one case, GRB970508, redshifted absorption lines have been detected, finally settling the debate about the distance scale. The consensus is that the burst sources lie at cosmological distances, requiring at least ∼ 1051 ergs to be emitted in gamma rays in just a few seconds. The gamma radiation is thought to be produced by shocks in a highly relativistic fireball. Many mysteries remain. There is no consensus on the nature of the sources, although coalescing neutron stars are the leading candidate. There is evidence that the sources of the faintest bursts may be at redshifts above 2. If so, gamma-ray bursts may ultimately tell us something about the early Universe.
Fiscal Policy in Developing Countries : A Framework and Some Questions

This paper surveys fiscal policy in developing countries from the point of view of long-run growth. The first section reviews existing methodologies to estimate the effects of fiscal policy shocks and of systematic fiscal policy, with time series or with cross-sectional methods, and their applicability to developing countries. The second section surveys optimal fiscal policy in developing countries, by considering the role of the intertemporal government budget, and sustainability and solvency. It also reviews the fuzzy debate on "fiscal space" and "macroeconomic space" - and the usefulness (or lack thereof) of these terms for policy analysis. The third section asks what theory tells us about the optimal cyclical behavior of fiscal policy in developing countries. It shows that it very much depends on the assumptions about the interactions between credit market imperfections at the individual, firms, or government level, and on the supply of external funds to the country. Different sets of assumptions lead to different implications about optimal cyclical behavior. The available evidence on the cyclical behavior of fiscal policy, and possible reasons for the observed prevalence of a procyclical behavior in developing countries, is also reviewed. If one agrees that fiscal policy is indeed less countercyclical than we think is optimal, the issue is how to correct the problem. One obvious question is why government do not self-insure, i.e. why they do not accumulate assets in upturns and decumulate them in downturns. This leads to the analysis of fiscal rules and stabilization funds, in the fourth section. The last section concludes with what the author considers important research and policy questions in each part.
Convenient synthesis of L-proline benzyl ester

Mesylates or tosylates of delta-hydroxy-L-norvaline esters spontaneously afford L-proline esters upon exposure to aqueous buffer in near quantitative yield. This novel reaction has led to the development of a simple route to optically active proline esters.
The magnification of sn 1997ff, the farthest known supernova

With a redshift of z {approx} 1.7, SN 1997ff is the most distant type Ia supernova discovered so far. This SN is close to several bright, z = 0.6-0.9 galaxies, and we consider the effects of lensing by those objects on the magnitude of SN 1997ff. We estimate their velocity dispersions using the Tully-Fisher and Faber-Jackson relations corrected for evolution effects, and calculate, applying the multiple-plane lensing formalism, that SN 1997ff is magnified by 0.34{+-}0.12 mag. Due to the spatial configuration of the foreground galaxies, the shear from individual lenses partially cancels out,and the total distortion induced on the host galaxy is considerably smaller than that produced by a single lens having the same magnification. After correction for lensing, the revised distance to SN 1997ff is m-M = 45.49 {+-} 0.34 mag, which improves the agreement with the {Omega}{sub M} = 0.35, {Omega}{Lambda} = 0.65 cosmology expected from lower-redshift SNe Ia, and is inconsistent at the {approx} 3 sigma confidence level with a uniform gray dust model or a simple evolution model.
Modelling fully convective stars in eclipsing binaries: KOI-126 and CM Draconis

We present models of the components of the systems KOI-126 and CM Draconis, the two eclipsing binary systems known to date to contain stars with masses low enough to have fully convective interiors. We are able to model satisfactorily the system KOI-126, finding consistent solutions for the radii and surface temperatures of all three components, using a solar-like value of the mixing-length parameter α in the convection zone and phoenix NextGen 1D model atmospheres for the surface boundary conditions. Depending on the chemical composition, we estimate the age of the system to be in the range 3–5 Gyr. For CM Draconis, on the other hand, we cannot reconcile our models with the observed radii and Teff using the current metal-poor composition estimate based on kinematics. Higher metallicities lessen but do not remove the discrepancy. We then explore the effect of varying the mixing-length parameter α. As previously noted in the literature, a reduced α can be used as a simple measure of the lower convective efficiency due to rotation and induced magnetic fields. Our models show a sensitivity to α (for α < 1.0) sufficient to partially account for the radius discrepancies. It is, however, impossible to reconcile the models with the observations on the basis of the effect of the reduced α alone. We therefore suggest that the combined effects of high metallicity and α reduction could explain the observations of CM Draconis. For example, increasing the metallicity of the system towards super-solar values (i.e. Z= 2 Z⊙) yields an agreement within 2σ with α= 1.0.
Positive expressions for skew divided difference operators

For permutations $$v,w \in \mathfrak S_n$$v,w?Sn, Macdonald defines the skew divided difference operators $$\partial _{w/v}$$?w/v as the unique linear operators satisfying $$\partial _w(PQ) = \sum _v v(\partial _{w/v}P) \cdot \partial _vQ$$?w(PQ)=?vv(?w/vP)·?vQ for all polynomials $$P$$P and $$Q$$Q. We prove that $$\partial _{w/v}$$?w/v has a positive expression in terms of divided difference operators $$\partial _{ij}$$?ij for $$i
A method for controlling phase difference between propagation channels for short-range MIMO transmission

Higher data rate wireless transmission systems are needed to meet the needs for high-speed wireless transmission of high definition videos and large files. In wireless communications, the multiple-input multiple-output (MIMO) transmission technique [1] has been gathering attention because it can increase the wireless transmission rate without expanding the frequency bandwidth through the use of multiple antennas at the transmitter and receiver. The MIMO technique has found practical consumer use in high-speed wireless LAN systems [2].
Exporter dynamics database

This paper introduces the Exporter Dynamics Database. The database includes exporter characteristics and measures of exporter growth based on firm-level customs information from 38 developing and seven developed countries, primarily for the period between 2003 and 2010. The measures are available at different levels of aggregation, including: a) country-year, b) country-year-product, and c) country-year-destination. Several new stylized facts about exporter behavior across countries emerge from the database. (i) Larger or more developed economies have more exporters, larger and more diversified exporters, and lower entry and exit rates than smaller or developing economies. (ii) In the short run, expansions along the intensive margin (exporter size) contribute more to export growth than expansions along the extensive margin (number of exporters). (iii) Exit rates are highly correlated with entry rates and both are negatively correlated with survival rates, average exporter size, and diversification. (iv) The number of exporters and the entry and exit rates in a country-product group are partially driven by country and product-group effects; however, the average size of exporters in a country-product group is not. Although the first three facts can be explained by models incorporating firm heterogeneity and uncertainty, the fourth fact is more difficult to explain with existing models. Several findings are confirmed in this database, including the importance of large multi-product firms. This database can be a valuable tool to improve the understanding of the micro-foundations of export growth, by providing new insights about exporter characteristics and dynamics.
Counter-Measures for Relay Failures due to Dynamic Welding: A Robust Engineering Design

In prior work, contact welding phenomena were observed in automotive relays during break of motor inrush current. The switching performance of the type of relay investigated could be correlated with the parameters: over-travel, coil suppression, and the break current. In the present work the author further explores the impact of both the contact material (silver tin oxide versus fine grain silver) and the contact surface topography (brand new and pre-aged contacts). He further assesses the robustness of the system “relay” with those parameters using the Taguchi methods for robust design. Furthermore, the robustness of two alternative automotive relay types will be discussed.
ON THE BIFURCATION FROM CONTINUOUS TO SEGMENTED CHIP FORMATION IN METAL CUTTING

We describe a new approach to modeling chip formation in orthogonal machining. Metal cutting is interpreted as a nonlinear dynamical process with thermo-mechanical feedback, that is similar in many ways to an open chemical reactor. As the cutting speed is increased, there is a bifurcation from steady-state to periodic oscillatory behavior in the stress and temperature fields in the workpiece material at the tooltip, which explains the observed change from continuous to segmented chip formation. We argue that this change in behavior corresponds to a singular Poincare-Andronov-Hopf bifurcation in the material flow.
Development as diffusion: Manufacturing productivity and sub-Saharan Africa's missing middle

We consider economic development of sub-Saharan Africa from the perspective of slow convergence of productivity, both across sectors and firms within sectors. Why have âproductivity enclavesâ, islands of high productivity in a sea of smaller low-productivity firms, not diffused more rapidly? We summarize and analyse three sets of factors: First, the poor business climate, which constraints the allocation of production factors between sectors and firms. Second, the complex political economy of business-government relations in Africaâs small economies, and third, the distribution of firm capabilities. The roots for these factors lie in subSaharan Africaâs geography and its distinctive history, including the legacy of its colonial period on state formation and market structure.
Economic well-being and anti-Semitic, xenophobic, and racist attitudes in Germany

The fear and hatred of others who are different has economic consequences because such feelings are likely to translate into discrimination in labor, credit, housing, and other markets. The implications range from earnings inequality to intergenerational mobility. Using German data from 1996 and 2006, we analyze the determinants of racist and xenophobic feelings towards foreigners in general, and against specific groups such as Italians, Turks, and Asylum Seekers. We also analyze racist and anti-Semitic feelings towards German citizens who differ in ethnicity (Aussiedler from Eastern Europe) or in religion (German Jews). Individuals’ perceived (or actual) economic well-being is negatively related to the strength of these feelings. Education, and having contact with foreigners mitigate racist, anti-Semitic and xenophobic feelings. People who live in states which had provided above-median support of the Nazi party in the 1928 elections have stronger anti-Semitic feelings today. The results are not gender-driven. They are not an artifact of economic conditions triggering feelings about job priority for German males, and they are not fully driven by fears about foreigners taking away jobs. The results of the paper are consistent with the model of Glaeser (Q J Econ 120(1):45–86, 2005) on hate, and with that of Akerlof and Kranton (Q J Econ 105(3):715–753, 2000; J Econ Perspect 19(1):9–32, 2005) on identity in the utility function.
On the relevance of freedom and entitlement in development : new empirical evidence (1975-2007)

Reviewing the economic performance -- good and bad -- of more than 100 countries over the past 30 years, this paper finds new empirical evidence supporting the idea that economic freedom and civil and political liberties are the root causes of why some countries achieve and sustain better economic outcomes. For instance, a one unit change in the initial level of economic freedom between two countries (on a scale of 1 to 10) is associated with an almost 1 percentage point differential in their average long-run economic growth rates. In the case of civil and political liberties, the long-term effect is also positive and significant with a differential of 0.3 percentage point. In addition to the initial conditions, the expansion of freedom conditions over time (economic, civil, and political) also positively influences long-run economic growth. In contrast, no evidence was found that the initial level of entitlement rights or their change over time had any significant effects on long-term per capita income, except for a negative effect in some specifications of the model. These results tend to support earlier findings that beyond core functions of government responsibility -- including the protection of liberty itself -- the expansion of the state to provide for various entitlements, including so-called economic, social, and cultural rights, may not make people richer in the long run and may even make them poorer.
On the Utility Consistency of Poverty Lines

Although poverty lines are widely used as deflators for inter-group welfare comparisons, their internal consistency is rarely given close scrutiny. A priori considerations suggest that commonly used methods cannot be relied upon to yield poverty lines that are consistent in terms of utility, or for capabilities more generally. The theory of revealed preference offers testable implications of utility consistency for "poverty baskets" under given preferences. A case study of Russia's official poverty lines reveals numerous violations of revealed preference criteria — violations that are not solely attributable to heterogeneity in preferences associated with climatic differences.
Coarse embeddings of metric spaces into Banach spaces

There are several characterizations of coarse embeddability of locally finite metric spaces into a Hilbert space. In this note we give such characterizations for general metric spaces. By applying these results to the spaces L p (μ), we get their coarse embeddability into a Hilbert space for 0 < p < 2. This together with a theorem by Banach and Mazur yields that coarse embeddability into l 2 and into Lp(0,1) are equivalent when 1 ≤ p < 2. A theorem by G.Yu and the above allow us to extend to L p (μ), 0 < p < 2, the range of spaces, coarse embeddings into which is guaranteed for a finitely generated group Γ to satisfy the Novikov Conjecture.
Noise Correction in Genomic Data

Osteogenesis Imperfecta (OI) is a genetic collagenous disease caused by mutations in one or both of the genes COLIA1 and COLIA2. There are at least four known phenotypes of OI, of which type II is the severest and often lethal. We applied a noise correction mechanism called polishing to a data set of amino acid sequences and associated information of point mutations of COLIA1. Polishing makes use of the inter-relationship between attribute and class values in the data set to identify and selectively correct components that are noisy. Preliminary results suggest that polishing is a viable mechanism for improving data quality, resulting in a more accurate classification of the lethal OI phenotype.
EMRinger: side chain-directed model and map validation for 3D cryo-electron microscopy

Advances in high-resolution cryo-electron microscopy (cryo-EM) require the development of validation metrics to independently assess map quality and model geometry. We report EMRinger, a tool that assesses the precise fitting of an atomic model into the map during refinement and shows how radiation damage alters scattering from negatively charged amino acids. EMRinger (https://github.com/fraser-lab/EMRinger) will be useful for monitoring progress in resolving and modeling high-resolution features in cryo-EM.
Reciprocal exchange networks: implications for macroeconomic stability

Decades of US and Swiss experience show that reciprocal exchange networks or "barter rings" are counter-cyclical-waxing as the business cycle wanes, and vice versa. These networks have important policy implications for new forms of e-commerce. Most studies of the Internet's macroeconomic impact focus on the stabilizing effect of greater price and inventory flexibility. The pre-Internet experience of these systems, however, suggests that expanded credit availability may be even more stabilizing-for networks that do not depend on monetary exchange.
Field experiments in strategy research

Strategy research often aims to empirically establish a causal relationship between an independent variable and a dependent variable such as firm performance. For many important strategy research questions, however, traditional empirical techniques are not sufficient to establish causal effects with high confidence. We propose that field experiments have potential to be used more widely in strategy research, leveraging methodological innovations from other disciplines to address persistent puzzles in the literature. We first review the advantages and disadvantages of using field experiments to answer questions in strategy. We define two types of experiments, “strategy field experiments” and “process field experiments,” and present an original example of each variety. The first study explores the liability of foreignness and the second study tests theories regarding corporate culture.
Local Fractional Frequency Shifts Used as Tracers of Magnetic Activity

Using data from SOI-MDI (Haber et al, 2000), we compute the local frequencies of high-degree p modes and f modes. The frequencies are obtained through ring-diagram mode fitting. The Dense-Pack data set consists of a mosaic of 189 overlapping tiles, each tracked separately at the surface rotation rate over 1664-min time intervals during the Dynamics Programs. Each tile is 16° square and the tile centers are separated by 7.5° in latitude and longitude. For each sampling day and for each tile, we have computed the frequency shift measured relative to the temporal and spatial average of the entire set of frequencies. The motion of active regions as they rotate across the solar disk is vividly traced by these measurements. Active regions appear as locations of large positive frequency shifts. If the shifts are averaged over the solar disk and are scaled down to the appropriate wave number regime, the magnitude and frequency dependence of the shifts are consistent with the measured changes in global oscillation frequencies that occur over the solar cycle. As with the frequency shifts of low-degree global oscillations, the frequency dependence of the shifts indicates that the physical phenomena inducing the shifts is confined to the surface layers of the Sun.
When does a central bank׳s balance sheet require fiscal support?

Abstract Using a simple, general equilibrium model, we argue that it would be appropriate for a central bank with a large balance sheet composed of long-duration nominal assets to have access to, and be willing to ask for, support for its balance sheet by the fiscal authority. Otherwise its ability to control inflation may be at risk. This need for balance sheet support — a within-government transaction — is distinct from the need for fiscal backing of inflation policy that arises even in models where the central bank׳s balance sheet is merged with that of the rest of the government.
Dissipation in the Moon: A Review of the Experimental Evidence and Physical Implications

Recent analyses of lunar ranging observations have revealed strong evidence of dissipation in the moon’s rotation (Ferrari et al. 1980; Cappallo et al. 1981). If interpreted as solid body friction, these results imply a tidal Q of about 25 (±5) at a frequency of one cycle per month. There is little evidence from other studies of the interior structure of the moon to support such a low solid-body Q. Yoder (1981) finds that turbulent fluid friction between the mantle and a core of radius ~300 km is a plausible mechanism to explain the observed dissipation. An iron or iron-sulfide core of this size is consistent with moment-of-inertia (Blackshear and Gapcynski 1977, Ferrari et al. 1980) and seismic (Goins et al. 1979) data, and is not excluded by conductivity data (Goldstein 1979). Stevenson and Yoder (1980) have proposed a model for formation of a solid iron inner core surrounded by a fluid iron sulfide layer of thickness 65–180 km.
The Informal Logic of Mathematical Proof

Informal and formal logic are complementary methods of argument analysis. Informal logic provides a pragmatic treatment of features of argumentation which cannot be reduced to logical form. This paper shows how paying attention to aspects of mathematical argumentation captured by informal, but not formal, logic can offer a more nuanced understanding of mathematical proof and discovery.
HORIZONS AND PLANE WAVES: A REVIEW

We review the attempts to construct black hole/string solutions in asymptotically plane wave spacetimes. First, we demonstrate that geometries admitting a covariantly constant null Killing vector cannot admit event horizons, which implies that pp-waves can't describe black holes. However, relaxing the symmetry requirements allows us to generate solutions which do possess regular event horizons while retaining the requisite asymptotic properties. In particular, we present two solution generating techniques and use them to construct asymptotically plane wave black string/brane geometries.
Technological Change and Immigration Policy

We propose a dynamic general equilibrium model to address the effects of technological progress on immigrant skill composition. Our results from this positive model suggest that neutral and skill-biased technological change imply essentially different immigration policies. On the one hand, skill-neutral change implies an immigrant skill distribution that is dominated by the native skill distribution; on the other hand, skill-biased change implies an immigrant over-representation at the top and bottom of the skill distribution. This result is interesting because of its unexpected nature. It implies that if technology changes as it has in the last decades and education has an increasing cost, then it is optimal to allow some low-skill immigration along with high-skill immigration. We show consistency of our model's predictions with data from the United States and Canada.
Contracting, Contesting, and Co-Optation: Civil Society Organizations’ Strategies under New Institutional Arrangements in Brazil

Civil society has exploded in Latin America as democratization has continued over the last 30 years. Civil society organizations (CSOs) are thought to improve governance and oversight and to increase social capital. Nonetheless, we have limited knowledge about what motivates CSOs’ political strategies, which include participating in formal political institutions, attending demonstrations, and providing services. We build knowledge here by evaluating data from a unique survey of nine hundred CSOs across seven Brazilian cities. Our findings showcase several parallel processes: poorer CSOs continue to rely on the state and actively participate in political processes despite protesting at greater rates than wealthier CSOs; therefore, we contend that institutional and political process arguments better explain poorer CSOs’ behavior. We also argue that relatively wealthy CSOs’ disengagement reflects greater resource mobilization, more professionalization, and an increase in social capital. Our results show that multilayered explanations improve our understanding of CSO behavior and state-society relations in Brazil and Latin America.
A triple lacunary generating function for Hermite polynomials

Some of the classical orthogonal polynomials such as Hermite, Laguerre, Charlier, etc. have been shown to be the generating polynomials for certain combinatorial objects. These combinatorial interpretations are used to prove new identities and generating functions involving these polynomials. In this paper we apply Foata's approach to generating functions for the Hermite polynomials to obtain a triple lacunary generating function. We define renormalized Hermite polynomials $h_n(u)$ by $$\sum_{n= 0}^\infty h_n(u) {z^n\over n!}=e^{uz+{z^2\!/2}}.$$ and give a combinatorial proof of the following generating function: $$ \sum_{n= 0}^\infty h_{3n}(u) {{z^n\over n!}}= {e^{(w-u)(3u-w)/6}\over\sqrt{1-6wz}} \sum_{n= 0}^\infty {{(6n)!\over 2^{3n}(3n)!(1-6wz)^{3n}} {z^{2n}\over(2n)!}}, $$ where $w=(1-\sqrt{1-12uz})/6z=uC(3uz)$ and $C(x)=(1-\sqrt{1-4x})/(2x)$ is the Catalan generating function. We also give an umbral proof of this generating function.
Hyper-responsive Toll-like receptor 7 and 9 activation in NADPH oxidase-deficient B lymphoblasts

Chronic granulomatous disease (CGD) is an inherited immunodeficiency linked with mutations in the multi-subunit leucocyte NADPH oxidase. Myeloid-derived phagocytic cells deficient in NADPH oxidase fail to produce sufficient levels of reactive oxygen species to clear engulfed pathogens. In this study we show that oxidase also influences B-cell functions, including responses to single-stranded RNA or unmethylated DNA by endosomal Toll-like receptors (TLRs) 7 and 9. In response to TLR7/9 ligands, B-cell lines derived from patients with CGD with mutations in either the NADPH oxidase p40(phox) or p47(phox) subunits produced only low levels of reactive oxygen species. Remarkably, cytokine secretion and p38 mitogen-activated protein kinase activation by these oxidase-deficient B cells was significantly increased upon TLR7/9 activation when compared with oxidase-sufficient B cells. Increased TLR responsiveness was also detected in B cells from oxidase-deficient mice. NADPH oxidase-deficient patient-derived B cells also expressed enhanced levels of TLR7 and TLR9 mRNA and protein compared with the same cells reconstituted to restore oxidase activity. These data demonstrate that the loss of oxidase function associated with CGD can significantly impact B-cell TLR signalling in response to nucleic acids with potential repercussions for auto-reactivity in patients.
Is Urbanization in Sub-Saharan Africa Different?

In the past dozen years, a literature has developed arguing that urbanization has unfolded differently in post-independence Sub-Saharan Africa than in the rest of the developing world, with implications for African economic growth overall. While African countries are more urbanized than other countries at comparable levels of income, it is well-recognized that total and sector gross domestic product data are of very low quality, especially in Africa. When instead viewed from the perspective of effective technology, as suggested in endogenous growth frameworks (and as proxied by educational attainment), the African urbanization experience overall matches global patterns. There are differences, however, at the sector level. Agricultural trade effects that improve farm prices deter African urbanization, while they promote urbanization elsewhere. Potential reasons include differences in land ownership institutions and the likelihood of agricultural surpluses being invested in urban production. Positive shocks to modern manufacturing spur urbanization in the rest of the developing world, but effects are dependent on the level of development. Thus many countries in Africa, with their lower level of development, do not respond to these shocks. Finally, historical indicators of the potential for good institutions promote urbanization both inside and outside Africa.
A NEW PERSPECTIVE ON DIRECTOR BUSYNESS

We provide a new perspective to the multiple directorships literature, which focuses on outside directors. Inside directors, however, are important in both the boardroom and day-to-day operations of the firm. We find that any negative effect of director busyness is more pervasive for inside directors than for outside directors. Additional analysis reveals that bidding firms' acquisition announcement returns are decreasing in inside director board appointments, but there is no such effect for outside directors. These results highlight the importance of inside directors and demonstrate that firm performance can be compromised when they sit on multiple boards.
Pulsed taut-wire measurement of the magnetic alignment of the ITS induction cells

The mechanical and magnetic alignment of the first eight induction-cell, solenoid magnets of the Integrated Test Stand (ITS) for the Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility were measured by observing the deflection of a fine, taut wire carrying a pulsed current. To achieve the required alignment (less than 0.25 mm offset and less than 5 mrad tilt), the magnet design uses quadrufilar windings and iron field-smoothing rings. After detailed measurements of each solenoid magnet, the cells are assembled and then mechanically aligned using a laser and an alignment target moved along the cell centerline. After the cells are in final position, the pulsed wire method is used to verify the magnetic alignment. The measurements show an average offset of the magnetic axes from the mechanical axis of 0.15 mm, with a maximum offset of 0.3 mm. The average tilt of the magnetic axes was 0.7 mrad with a maximum tilt of 1.4 mrad. Tilts are corrected to less than 0.3 mrad, using dipole trim magnets assembled into each cell. Correction is limited by power supply resolution and by background noise. >