cssi/SciSciGPT-SciSciNet huggingface dataset:
Physical Activity and Weight Management Across the Lifespan

This review discusses key findings and recommendations related to the role of physical activity in weight gain prevention, weight loss, and weight-loss maintenance across the lifespan. For weight gain prevention, epidemiological and clinical studies suggest that regular physical activity is critical, with increases above the recommended 30 min daily for health (e.g., to 45 to 60 min daily) potentially desirable for curtailing weight gain. For weight loss, clinical studies suggest that physical activity interventions alone usually produce only modest results. Combining physical activity with dietary interventions increases the chance of success, especially at higher levels of physical activity (e.g., 200 to 300 min or more weekly). For weight-loss maintenance, high levels of physical activity (e.g., 40 to 90 min daily) may be necessary. To manage weight across the lifespan, a comprehensive approach to physical activity is needed supported by public policy interventions that help make physical activity a part of daily life.
Ethical and practical issues regarding research in children. The European perspective

Children, like all humans, are exposed to compounds in the environment and sometimes to drugs. The effect of this exposure cannot simply be deducted from studies in adults or animals. Effects might be different and even more dramatic than in adults due to the stage of growth and development of the infant. Around 80% of drugs used in young individuals are not licensed for use in this age group. Almost three new chemical compounds enter the environment each day. Toxicological studies in infants and children therefore are needed and ethically acceptable. However, appropriate safeguards must be taken into account. According to the Good Clinical Practice Directive of the European Parliament (2001/20) not only therapeutic, but also non-therapeutic research in infants and children is allowed, provided the study can only be conducted in children, and the results of the study in children will be of benefit to the group represented and no more than minimal harm and risk is inflicted to the children. Many more toxicological studies are needed in children and infants. Not conducting these studies is detrimental for this age group.
Direct numerical simulation of sensitivity coefficients in low Reynolds number turbulent channel flow

The sensitivity equation method (SEM) has been implemented in direct numerical simulations (DNS) of smooth-wall turbulent channel flow to quantify Reynolds number effects on the mean flow field. The present approach towards sensitivity analysis represents a departure from conventional parametric studies wherein multiple numerical simulations are performed with discrete increments in the value of the parameter of interest, in this case the Reynolds number. In the present study, sensitivity derivatives (or sensitivity coefficients) represent the rate of change of the primitive variables with respect to the Reynolds number, and are determined directly by numerically solving the discretized continuous sensitivity equations concurrently with the discretized Navier–Stokes equations. Simulations have been performed at Reynolds numbers of 100 and 180, based on the friction velocity and channel half-width, using a finite volume computational scheme. Wall-normal profiles of the mean streamwise velocity and Reynolds...
Co-Production of Prolonged, Complex, and Negative Services An Examination of Medication Adherence in Chronically Ill Individuals

This study examines customer coproduction in a prolonged, complex, and negative service context—medication adherence in chronically ill individuals. We integrate services and medical perspectives t...
Comprehensive System for Classification and Nomenclature of Organic Reactions

Previous authors' ideas on reaction classification have been incorporated into a unified and comprehensive system to record the bonding change in any reaction. The system offers a “reaction logo” as a single drawing of the bonding change at the reaction center. It also provides a smooth hierarchy of increasing detail from the two monocyclic basic forms (homovalent and ambivalent), through their subclasses of unchanging shell σ-bonds on the reaction center, to the full detail of the individual atom types in the reaction center. A simple linear notation incorporates all of this information in a form such as −3L[OCCCOH], for the reaction center of the aldol reaction.
Dynamic rupture on a bimaterial interface governed by slip-weakening friction

SUMMARY We perform 2-D finite-difference calculations of mode II rupture along a bimaterial interface governed by slip-weakening friction, with the goal of clarifying rupture properties and the conditions leading to the development of unilateral wrinkle-like pulses. The simulations begin with an imposed bilateral rupture in a limited source region. Rupture properties outside the imposed source are examined for ranges of values of the degree of material contrast γ across the fault, the difference between static fs and dynamic fd coefficients of friction, and the difference between static friction and initial shear stress. The results show that mode II rupture evolves with propagation distance along a bimaterial interface, for broad ranges of realistic conditions, to a unilateral wrinkle-like pulse in the direction of slip on the compliant side of the fault. These conditions span in our calculations the ranges fs − fd 2‐ 5 per cent. When the difference between the static friction and initial shear stress is smaller, the evolution to unilateral wrinkle-like pulses occurs for smaller values of γ . The amount of slip increases with propagation distance, due to the incorporation of slip-weakening friction, in contrast to earlier results based on Coulomb and Prakash‐Clifton friction laws with slipindependent coefficient. In all cases leading to wrinkle-like pulses, the rupture velocity in the preferred (+) propagation direction is V + ≈ CGR, where CGR is the generalized Rayleigh wave speed. Simulations with imposed rupture speed in the source region close to the slower P wave speed P − can excite, in addition to the primary wrinkle-like pulse in the preferred direction with V + ≈ CGR, a weak pulse in the opposite (−) direction with V − ≈ P − . In some cases leading to bilateral crack-like propagation (e.g. fs − fd = 0.7), the rupture velocities in the opposite directions are V + ≈ P + (the faster P wave speed) and V − ≈ P − , with the initial supershear crack front in the + direction followed by a pulse with V + r ≈ CGR.
Organocatalytic mannich-type reactions of trifluoroethyl thioesters.

Direct organocatalytic Mannich-type reactions of thioesters provide for the expedient and diastereoselective synthesis of protected β-amino acids. A variety of thioesters were found to be reactive with different imines under mild conditions to provide β-amino acids in good yields. This chemistry was extended to a diastereo- and enantioselective variant.
Pattern Recognition for Automatic Visual Inspection

Three major approaches to pattern recognition, (1) template matching, (2) decision-theoretic approach, and (3) structural and syntactic approach, are briefly introduced. The application of these approaches to automatic visual inspection of manufactured products are then reviewed. A more general method for automatic visual inspection of IC chips is then proposed. Several practical examples are included for illustration.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Derived functors and Hilbert polynomials

Let R be a commutative Noetherian ring, I an ideal, M and N finitely generated R -modules. Assume V ( I ) [xcap ] Supp ( M ) [xcap ] Supp ( N ) consists of finitely many maximal ideals and let λ(Ext i ( N / I n N , M )) denote the length of Ext i ( N / I n N , M ). It is shown that λ(Ext i ( N / I n N , M )) agrees with a polynomial in n for n [Gt ] 0, and an upper bound for its degree is given. On the other hand, a simple example shows that some special assumption such as the support condition above is necessary in order to conclude that polynomial growth holds.
Lowering the barrier to applying machine learning

Researchers have used machine learning algorithms to solve hard problems in a variety of domains, enabling exciting, new applications of computing. However, research results have not transferred to software solutions. In part, this is because developing software with machine learning algorithms is itself difficult. My dissertation work aims to understand why using machine learning is difficult and to create tools that lower the bar so that more developers can effectively use machine learning.
A method for producing a shaped contour radiation pattern using a single shaped reflector and a single feed

Eliminating the corporate feed network in shaped contour beam antennas will reduce the expense, weight, and RF loss of the antenna system. One way of producing a shaped contour beam without using a feed network is to use a single shaped reflector with a single feed element. For a prescribed contour beam and feed, an optimization method for designing the reflector shape is given. As a design example, a shaped reflector is designed to produce a continental-United-States (CONUS) coverage beam. The RF performance of the shaped reflector is then verified by physical optics. >
A Sentence Compression Based Framework to Query-Focused Multi-Document Summarization

We consider the problem of using sentence compression techniques to facilitate queryfocused multi-document summarization. We present a sentence-compression-based framework for the task, and design a series of learning-based compression models built on parse trees. An innovative beam search decoder is proposed to efficiently find highly probable compressions. Under this framework, we show how to integrate various indicative metrics such as linguistic motivation and query relevance into the compression process by deriving a novel formulation of a compression scoring function. Our best model achieves statistically significant improvement over the state-of-the-art systems on several metrics (e.g. 8.0% and 5.4% improvements in ROUGE-2 respectively) for the DUC 2006 and 2007 summarization task.
Peptide Nanostructures with π‐Ways: Photophysical Consequences of Peptide/π‐Electron Molecular Self‐Assembly

This article provides a summary of the electronic outcomes that result as oligopeptides with embedded π-conjugated units are drawn together into hierarchical 1D assemblies reminiscent of amyloid plaques or other protein deposits associated with neurodegenerative diseases. The baseline photophysics of prototype molecules are presented, followed by a description of how subtle molecular variations further perturb these responses in manners relevant to several cutting-edge optoelectronic applications. For example, the influence of amino acid residue steric bulk/hydrophobicity and peptide N-to-C sequence variation are explicated, showing excited-state variations in the excimeric or excitonic nature of the intermolecular π-electron delocalization that result as the π-conjugated peptides are driven to assemble into extended 1D fibrillar assemblies.
Nonparametric option pricing under shape restrictions

Frequently, economic theory places shape restrictions on functional relationships between economic variables. This paper develops a method to constrain the values of the first and second derivatives of nonparametric locally polynomial estimators. We apply this technique to estimate the state price density (SPD), or risk-neutral density, implicit in the market prices of options. The option pricing function must be monotonic and convex. Simulations demonstrate that nonparametric estimates can be quite feasible in the small samples relevant for day-to-day option pricing, once appropriate theory-motivated shape restrictions are imposed. Using S&P 500 option prices, we show that unconstrained nonparametric estimators violate the constraints during more than half the trading days in 1999, unlike the constrained estimator we propose.
Moral advice and moral theory

Monists, pluralists, and particularists disagree about the structure of the best explanation of the rightness (wrongness) of actions. In this paper I argue that the availability of good moral advice gives us reason to prefer particularist theories and pluralist theories to monist theories. First, I identify two distinct roles of moral theorizing—explaining the rightness (wrongness) of actions, and providing moral advice—and I explain how these two roles are related. Next, I explain what monists, pluralists, and particularists disagree about. Finally, I argue that particularists and pluralists are better situated than monists to explain why it is a good idea to think before we act, and that this gives us reason to favor particularism and pluralism over monism.
Genes Associated With Alcohol Outcomes Show Enrichment of Effects With Broad Externalizing and Impulsivity Phenotypes in an Independent Sample

Objective: The purpose of this study was to evaluate evidence for association with a panel of genes previously associated with alcohol-related traits in a new sample of adolescent and young adult in- dividuals (N = 2,128; 51% female) collected as part of the Collaborative Study on the Genetics of Alcoholism (COGA). We tested for association with phenotypes related to externalizing behavior, including diagnostic symptom counts for disorders on the externalizing spectrum (alcohol dependence, conduct disorder, adult antisocial personality disorder, and illicit drug dependence), and related behavioral/personality traits (Achenbach Externalizing, NEO Extraversion, NEO Conscientiousness, Zuckerman's Sensation Seeking, and the Barratt Impulsivity Scale) based on the substantial literature suggesting that these behaviors may be alternate manifestations of a shared genetic liability. Method: We tested for overall enrichment of the set of 215 genotyped single-nucleotide polymorphisms (SNPs) for each of the phenotypes. We conducted secondary analyses comparing results for sensation seeking with results for the other phenotypes. Results: For all phenotypes, there was signifi - cant enrichment of association results (p < .05) compared with chance expectations. The greatest number of signifi cant results was observed with the phenotype Sensation Seeking. Secondary analyses indicated that the number of SNPs yielding p < .05 with Sensation Seeking was signifi cantly greater than that observed for each of the other phenotypes. Conclusions: We fi nd evidence for enrichment of association results across a spectrum of externalizing phenotypes with a panel of candidate genes/SNPs selected based on previous suggestion of association with alcohol-related outcomes. In particular, we fisignifi cant enrichment of effects with sensation seeking, suggesting that this may be a particularly salient behavior associated with risk for alcohol-related problems. (J. Stud. Alcohol Drugs, 76, 38-46, 2015)
Conditional Spectral Analysis of Replicated Multiple Time Series With Application to Nocturnal Physiology

ABSTRACTThis article considers the problem of analyzing associations between power spectra of multiple time series and cross-sectional outcomes when data are observed from multiple subjects. The motivating application comes from sleep medicine, where researchers are able to noninvasively record physiological time series signals during sleep. The frequency patterns of these signals, which can be quantified through the power spectrum, contain interpretable information about biological processes. An important problem in sleep research is drawing connections between power spectra of time series signals and clinical characteristics; these connections are key to understanding biological pathways through which sleep affects, and can be treated to improve, health. Such analyses are challenging as they must overcome the complicated structure of a power spectrum from multiple time series as a complex positive-definite matrix-valued function. This article proposes a new approach to such analyses based on a tensor-pr...
Moral hazard, hold-up, and the optimal allocation of control rights

I examine the optimal allocation of control rights in a model with manager moral hazard, where the manager and investor may hold up each other ex post. The control allocation determines both the likelihood of hold-up and the agents’ renegotiation payoffs. In equilibrium, only two control allocations are optimal: either exclusive investor control or a contingent control allocation that allows the manager to remain in control if, and only if, interim performance is good. Thus, my model explains why it may be optimal to link control to thefirm’s performance such that managers retain control only following good performance.
The Physics of Cosmic Acceleration

The discovery that the cosmic expansion is accelerating has been followed by an intense theoretical and experimental response in physics and astronomy. The discovery implies that our most basic not...
Recalibration of Bartels' geomagnetic activity indices Kp and ap to include universal time variations

The ap index (and derived indices) can be recalibrated by using Mayaud's am index to recover the correct universal time variations. Such variations were artificially removed in the original ap index. A number of tests are performed to show that the corrected index is capable of revealing the desired variations. These tests include comparisons of the universal time variations on days of opposite interplanetary magnetic sector polarity. The finding that geomagnetic activity was considerably higher during intervals of toward polarity prior to 1963 is strongly confirmed.
High‐Throughput Strategies for the Discovery of Catalysts

Are there more efficient ways to discover new catalysts? Classical efforts, while very successful, have been typically quite linear in design. In contrast, early efforts using diversity-based techniques such as parallel synthesis and screening (right) to rapidly identify and optimize new catalysts are beginning to yield some promising results.
Impact of agronomic uncertainty in biomass production and endogenous commodity prices on cellulosic biofuel feedstock composition

This paper evaluates the effect of agronomic uncertainty on bioenergy crop production as well as endogenous commodity and biomass prices on the feedstock composition of cellulosic biofuels under a binding mandate in the United States. The county-level simulation model focuses on both field crops (corn, soybean, and wheat) and biomass feedstocks (corn stover, wheat straw, switchgrass, and miscanthus). In addition, pasture serves as a potential area for bioenergy crop production. The economic model is calibrated to 2022 in terms of yield, crop demand, and baseline prices and allocates land optimally among the alternative crops given the binding cellulosic biofuel mandate. The simulation scenarios differ in terms of bioenergy crop type (switchgrass and miscanthus) and yield, biomass production inputs, and pasture availability. The cellulosic biofuel mandates range from 15 to 60 billion liters. The results indicate that the 15 and 30 billion liter mandates in the high production input scenarios for switchgrass and miscanthus are covered entirely by agricultural residues. With the exception of the low production input for miscanthus scenario, the share of agricultural residues is always over 50% for all other scenarios including the 60 billion liter mandate. The largest proportion of agricultural land dedicated to either switchgrass or miscanthus is found in the Southern Plains and the Southeast. Almost no bioenergy crops are grown in the Midwest across all scenarios. Changes in the prices for the three commodities are negligible for cellulosic ethanol mandates because most of the mandate is met with agricultural residues. The lessons learned are that (1) the share of agricultural residue in the feedstock mix is higher than previously estimated and (2) for a given mandate, the feedstock composition is relatively stable with the exception of one scenario.
Universal anisotropic condensation transition of gases in nanotube bundles

Gases adsorbed within bundles of carbon nanotubes (inside of the nanotubes or in the interstitial channels between the tubes) exhibit a variety of phase transitions with the help of interactions between molecules in neighboring channels or tubes. Because the channels/tubes are widely separated, these transverse interactions are weaker than the (longitudinal) interactions within the same channel. The transition temperatures that result are therefore lower than those of typical two- or three-dimensional transitions of the same species of molecules. We discuss here the condensation transition of such a gas to form a liquid, expressing the transition behavior in universal form, where the reduced critical temperature T*c is a universal function of the reduced transverse interaction.
Direct and indirect algorithms for on-line learning of disjunctions

It is easy to design on-line learning algorithms for learning k out of n variable monotone disjunctions by simply keeping one weight per disjunction. Such algorithms use roughly O(nk) weights which can be prohibitively expensive. Surprisingly, algorithms like Winnow require only n weights (one per variable or attribute) and the mistake bound of these algorithms is not too much worse than the mistake bound of the more costly algorithms. The purpose of this paper is to investigate how exponentially many weights can be collapsed into only O(n) weights. In particular, we consider probabilistic assumptions that enable the Bayes optimal algorithm's posterior over the disjunctions to be encoded with only O(n) weights. This results in a new O(n) algorithm for learning disjunctions which is related to the Bylander's BEG algorithm originally introduced for linear regression. Besides providing a Bayesian interpretation for this new algorithm, we are also able to obtain mistake bounds for the noise free case resembling those that have been derived for the Winnow algorithm. The same techniques used to derive this new algorithm also provide a Bayesian interpretation for a normalized version of Winnow.
Quantifier Scope and Constituency

Traditional approaches to quantifier scope typically need stipulation to exclude readings that are unavailable to human understanders. This paper shows that quantifier scope phenomena can be precisely characterized by a semantic representation constrained by surface constituency, if the distinction between referential and quantificational NPs is properly observed. A CCG implementation is described and compared to other approaches.
The residue number system

In this paper we develop and investigate the properrties of a novel system, called the residue code or residue number system. The residue number system is of particular interest because the arithmetic operations of addition and multiplication may be executed in the same time as required for an addition operation. The main difficulty of the residue code relative to arithmetic operations is the determination of the relative magnitude of two numbers expressed in the residue code. The residue code is probably of little utility for general-purpose computation, but the code has many characteristics which recommend its use for special-purpose computations.
Evaluating And Selecting Technology‐Based Projects

Evaluating and selecting projects is both an art and a science that, for most cases, has to go beyond a simple cost-benefit analysis. Virtually every organization selects and implements projects, ranging from product development to organizational improvements and from customer contracts to R&D activities and bid proposals. Well-organized project evaluation and selection process provides the framework for systematic data gathering and informed decision making toward resource allocation. Quantitative approaches are often favored to support project evaluation and selections if the decisions require economic justification. Effective project evaluation and selection requires a broad-scanning process across all segments of the enterprise and its environment to deal with the risks, uncertainties, ambiguities, and imperfections of data available for assessing the value of a new project venture relative to other opportunities. Finally, organizational strategy must be aligned and integrated with the evaluation/selection process, early and throughout its evaluation cycle. Keywords: broad-scanning process; cost-benefit analysis; organizational strategy; project evaluation; project selections; quantitative approaches
Variational Transition State Theory

In recent years our research group has made a systematic effort to study the validity of transition state theory (TST). We have found that the conventional theory is sometimes remarkably accurate, but in many other cases it leads to large errors. Fortunately we have found that a much more reliable theory that has many of the advantages of conventional TST can also be formulated, and it can be applied to practical problems with an effort that is much closer to that required for conventional transition state theory than to that required for quantal dynamics calculations. The two most important features in the improved approach to transition state theory state theory are the variational determination of the transition state and the incorporation of tunneling contributions by multidimensional semiclassical approximations. 13 refs.
New π-Delocalized Persistent Radicals

Progress in the theoretical and experimental investigation of heterocyclic radicals suitable for incorporation into the structure of a liquid crystalline molecule is described. Five classes of heterocyclic systems are discussed, including their methods of preparation, stability and further functionalization to form potentially mesogenic materials.
Rapid phospho-turnover by receptor tyrosine kinases impacts downstream signaling and drug binding.

SUMMARY Epidermal growth factor receptors (ErbB1–4) are oncogenic receptor tyrosine kinases (RTKs) that regulate diverse cellular processes. In this study, we combine measurement and mathematical modeling to quantify phospho-turnover at ErbB receptors in human cells and to determine the consequences for signaling and drug binding. We find that phosphotyrosine residues on ErbB1 have half-lives of a few seconds and therefore turn over 100–1000 times in the course of a typical immediate-early response to ligand. Rapid phospho-turnover is also observed for EGF-activated ErbB2 and ErbB3, unrelated RTKs, and multiple intracellular adaptor proteins and signaling kinases. Thus, the complexes formed on the cytoplasmic tail of active receptors and the downstream signaling kinases they control are highly dynamic and antagonized by potent phosphatases. We develop a kinetic scheme for binding of antiErbB1 drugs to receptors and show that rapid phospho-turnover significantly impacts their mechanisms of action.
Process planning: a knowledge-based and optimization perspective

Process planning for a part involves preparation of a plan that outlines the processing route, operations, machine tools, and so on. The decomposition of the process-planning task into eight phases is discussed. For each phase, problems and suitable solution approaches are discussed. Most process-planning problems are solved using a knowledge-based approach or a combination of optimization and knowledge-based approaches. The knowledge-based approach solves the qualitative subproblems, and the optimization perspective tackles the quantitative aspect of the subproblems. The concepts presented are illustrated with examples. >
Copper-in-Charcoal-Catalyzed, Tandem One-Pot Diazo Transfer-Click Reactions

Copper-in-charcoal (Cu/C) is an effective heterogeneous catalyst for tandem diazo transfer/ click reactions. In the presence of Cu/C, various azides can be generated in situ from the corresponding amines, and subsequently undergo [3+ 2] cycloaddition with terminal alkynes to afford triazoles in good yields. The catalyst is also easily recycled.
High-speed low-power ECL circuit with AC-coupled self-biased dynamic current source and active-pull-down emitter-follower stage

The design of an ECL circuit with AC-coupled self-biased dynamic current source and active-pull-down emitter-follower stage for low-power high-speed gate array applications is presented. The circuit features an AC-coupled dynamic current source to improve the power-delay of the logic stage (current switch). A self-biasing scheme for the dynamic current source and the active-pull-down transistor with no additional devices and power in the biasing circuit is described. Based on a 0.8- mu m double-poly, self-aligned bipolar technology at a power consumption of 1.0 mW/gate, the circuit offers 1.62* (1.90*) improvement in the speed (load driving capability) of a loaded gate compared with the conventional ECL circuit. >
Reasoning Under the Principle of Maximum Entropy for Modal Logics K45, KD45, and S5

We propose modal Markov logic as an extension of propositional Markov logic to reason under the principle of maximum entropy for modal logics K45, KD45, and S5. Analogous to propositional Markov logic, the knowledge base consists of weighted formulas, whose weights are learned from data. However, in contrast to Markov logic, in our framework we use the knowledge base to dene a probability distribution over non-equivalent epistemic situations (pointed Kripke structures) rather than over atoms, and use this distribution to assign probabilities to modal formulas. As in all probabilistic representations, the central task in our framework is inference. Although the size of the state space grows doubly exponentially in the number of propositions in the domain, we provide an algorithm that scales only exponentially in the size of the knowledge base. Finally, we briey discuss the case of languages with an innite number of propositions.
Temperature and Carbon Assimilation Regulate the Chlorosome Biogenesis in Green Sulfur Bacteria

Green photosynthetic bacteria adjust the structure and functionality of the chlorosome—the light-absorbing antenna complex—in response to environmental stress factors. The chlorosome is a natural self-assembled aggregate of bacte- riochlorophyll (BChl) molecules. In this study, we report the regulation of the biogenesis of the Chlorobaculum tepidum chloro- some by carbon assimilation in conjunction with temperature changes. Our studies indicate that the carbon source and thermal stress culture of C. tepidum grows slower and incorporates fewer BChl c in the chlorosome. Compared with the chlorosome from other cultural conditions we investigated, the chlorosome from the carbon source and thermal stress culture displays (a) smaller cross-sectional radius and overall size, (b) simplified BChl c homologs with smaller side chains, (c) blue-shifted Qy absorption maxima, and (d) a sigmoid-shaped circular dichroism spectra. Using a theoretical model, we analyze how the observed spectral modifications can be associated with structural changes of BChl aggregates inside the chlorosome. Our report suggests a mech- anism of metabolic regulation for chlorosome biogenesis.
An ortho-directed C–H borylation/Suzuki coupling sequence in the formation of biphenylbenzylic amines

A C–H borylation/Suzuki–Miyaura coupling sequence is reported using benzylic amines to direct the C–H borylation to the ortho C–H bond. Both aryl bromides and iodides were coupled to the resulting arylboronate esters. A series of biphenylbenzylic amines are reported, requiring a single purification in the two-step reaction sequence.
Were Former Andersen Clients Treated More Leniently Than Other Clients? Evidence from Going‐Concern Modified Audit Opinions

In the wake of the collapse of Enron and Andersen, several questions were raised about Enron's accounting and the behavior of its auditor. An important question is whether ex‐Andersen's clients received more conservative treatment by their new auditors, either due to a greater perceived litigation risk because of their previous association with Andersen or because of a “correction” of alleged lax auditing by Andersen. We examine going‐concern modified audit opinions for former clients of Arthur Andersen, and compare them with opinions issued for other newly acquired clients. We find that auditors were less likely to issue going‐concern modified audit opinions to small clients who switched from Andersen than to their existing clients. However, this trend reverses with an increase in client size, with large former Andersen clients more likely to receive going‐concern opinions. Our results are consistent with suggestions that increased litigation risk associated with the larger ex‐Andersen clients led to inc...
Multidimensional analysis of the frequencies and rates of cytokine secretion from single cells by quantitative microengraving

The large diversity of cells that comprise the human immune system requires methods that can resolve the individual contributions of specific subsets to an immunological response. Microengraving is process that uses a dense, elastomeric array of microwells to generate microarrays of proteins secreted from large numbers of individual live cells (∼104–105 cells/assay). In this paper, we describe an approach based on this technology to quantify the rates of secretion from single immune cells. Numerical simulations of the microengraving process indicated an operating regime between 30 min–4 h that permits quantitative analysis of the rates of secretion. Through experimental validation, we demonstrate that microengraving can provide quantitative measurements of both the frequencies and the distribution in rates of secretion for up to four cytokines simultaneously released from individual viable primary immune cells. The experimental limits of detection ranged from 0.5 to 4 molecules/s for IL-6, IL-17, IFNγ, IL-2, and TNFα. These multidimensional measures resolve the number and intensities of responses by cells exposed to stimuli with greater sensitivity than single-parameter assays for cytokine release. We show that cells from different donors exhibit distinct responses based on both the frequency and magnitude of cytokine secretion when stimulated under different activating conditions. Primary T cells with specific profiles of secretion can also be recovered after microengraving for subsequent expansion in vitro. These examples demonstrate the utility of quantitative, multidimensional profiles of single cells for analyzing the diversity and dynamics of immune responses in vitro and for identifying rare cells from clinical samples.
Asymmetric Vortices on a Slender Body of Revolution

The symmetric and asymmetric leeward-side flow fields on an inclined ogive-cylinder have been investigated using a number of experimental techniques. Naturally occurring and perturbed flow fields were studied at a moderate Reynolds number and at many incidence angles. By close examination of the steady side force behavior at different roll orientations of the tip, it has been established that micro-variations in the tip geometry of the model have a large influence on the downstream development of the flow field. Under certain conditions, a bistable flow field was observed.
Gravitational Waves from Merging Compact Binaries

Largely motivated by the development of highly sensitive gravitational-wave detectors, our understanding of merging compact binaries and the gravitational waves they generate has improved dramatically in recent years. Breakthroughs in numerical relativity now allow us to model the coalescence of two black holes with no approximations or simplifications. There has also been outstanding progress in our analytical understanding of binaries. We review these developments, examining merging binaries using black hole perturbation theory, post-Newtonian expansions, and direct numerical integration of the field equations. We summarize these approaches and what they have taught us about gravitational waves from compact binaries. We place these results in the context of gravitational-wave generating systems, analyzing the impact gravitational-wave emission has on their sources, as well as what we can learn about them from direct gravitational-wave measurements.
On tokamak equilibrium

Large-aspect-ratio tokamak equilibrium is studied, including effects, such as ellipticity of the flux surfaces, of second order in the inverse aspect ratio. To facilitate the interpretation of experimental data, the analysis uses simple coordinates that are readily evaluated, rather than co-ordinates based on the exact flux surfaces. An explicit formula for the safety factor, including second-order terms, is presented, along with a brief discussion of rotational effects. The analysis assumes near-circularity of the outermost closed surface and low plasma pressure.
The Vanadium(V) Oxoazides [VO(N3)3], [(bipy)VO(N3)3], and [VO(N3)5]2−

Vanadium(V) oxoazide [VO(N3)3] was prepared through a fluoride–azide exchange reaction between [VOF3] and Me3SiN3 in acetonitrile solution. When the highly impact- and friction-sensitive compound [VO(N3)3] was reacted with 2,2′-bipyridine, the adduct [(bipy)VO(N3)3] was isolated. The reaction of [VO(N3)3] with [PPh4]N3 resulted in the formation and isolation of the salt [PPh4]2[VO(N3)5]. The adduct [(bipy)VO(N3)3] and the salt [PPh4]23[VO(N3)5] were characterized by vibrational spectroscopy and single-crystal X-ray structure determination, making these compounds the first structurally characterized vanadium(V) azides.
A model-based approach to robot joint control

Despite efforts to design precise motor controllers, robot joints do not always move exactly as desired. This paper introduces a general model-based method for improving the accuracy of joint control. First, a model that predicts the effects of joint requests is built based on empirical data. Then this model is approximately inverted to determine the control requests that will most closely lead to the desired movements. We implement and validate this approach on a popular, commercially available robot, the Sony Aibo ERS-210A.
Health Insurance for the Poor: Initial Impacts of Vietnam's Health Care Fund for the Poor

Vietnam's Health Care Fund for the Poor (HCFP) uses government revenues to finance health care for the poor, ethnic minorities living in selected mountainous provinces designated as difficult, and all households living in communes officially designated as highly disadvantaged. The program, which started in 2003, did not as of 2004 include all these groups, but those who were included (about 15 percent of the population) were disproportionately poor. Estimates of the program's impact-obtained using single differences and propensity score matching on a trimmed sample-suggest that HCFP has substantially increased service utilization, especially in-patient care, and has reduced the risk of catastrophic spending. It has not, however, reduced average out-of-pocket spending, and appears to have had negligible impacts on utilization among the poorest decile.
Size and industry effects in the performance of agricultural cooperatives

Abstract The objective of this study is to determine if there are important size and industry effects of financial performance of agricultural cooperatives. The performance of 43 dairy, food, grain, and farm supply cooperatives in the U.S. was analyzed over the period 1970–1987 using financial ratios derived from accounting data. The analysis revealed significant size and industry effects. Large regional cooperatives are more efficient in utilizing their assets to generate sales, while small regional cooperatives have higher profitability. The findings suggest that the emphasis on growth may not always produce beneficial results among agricultural cooperatives. Among the four industries studied, the dairy regional cooperatives appear to be the strongest performers, while the food marketing cooperatives are characterized by the lowest performance measures. Since both dairy and food cooperatives engage in value-added processing, this difference in performance makes it difficult to reach clear conclusions about possible advantages of disadvantages or vertical integration relative to traditional cooperative activities. Trend analysis indicates that the profitability of the agricultural cooperatives in all industry and size categories declined in response to the downturn in U.S. agriculture after 1980. While the decline in profitability was at similar rates for both large and small cooperatives, the variation of efficiency and leverage was in opposite directions. Large cooperatives may be expected to continue improving their asset utilization without relative improvement in profitability, and increasing the level of their debt in relation to equity.
The information paradox: Conflicts and resolutions

Many relativists have been long convinced that black hole evaporation leads to information loss or remnants. String theorists have however not been too worried about the issue, largely due to a belief that the Hawking argument for information loss is flawed in its details. A recently derived inequality shows that the Hawking argument for black holes with horizon can in fact be made rigorous. What happens instead is that in string theory, black hole microstates have no horizons. Thus the evolution of radiation quanta with E∼kT is modified by order unity at the horizon, and we resolve the information paradox.
From Financial Crash to Debt Crisis

Newly developed historical time series on public debt, along with data on external debts, allow a deeper analysis of the debt cycles underlying serial debt and banking crises. We test three related hypotheses at both “world” aggregate levels and on an individual country basis. First, external debt surges are an antecedent to banking crises. Second, banking crises (domestic and those in financial centers) often precede or accompany sovereign debt crises; we find they help predict them. Third, public borrowing surges ahead of external sovereign default, as governments have “hidden domestic debts” that exceed the better documented levels of external debt.
Making Globalization Work: Towards Global Economic Justice

Globalization as a corporate-led process has come under much justifiable criticism. This paper attempts to give the term analytic content distinct from its more ideological formulations.. It then focuses on a normative analysis of globalization from the capabilities perspective. A freedom-centered perspective such as the capabilities approach emphasizes policies and institutions that can enhance freedom globally and locally. A global governance structure based on transparent principles of both economic efficiency and social justice is shown to be a desirable state of affairs; however, the present fractured process of globalization is more likely to end up in a fragmenting regionalism or even national protectionism and rivalry. Multilateral cooperation on the basis of the framework advanced here is an urgent necessity.To this end the creation of international regimes of cooperation in areas ranging from trade and finance to ecological and women's and minorities rights issues must be put on the international and national social and political agendas
Periodic chirality transformations propagating on bacterial flagella

When a helical bacterial flagellum, clamped at one end, is placed in an external flow, it has been observed that regions of the flagellum transform to the opposite chirality, and travel as pulses down the length of the filament, the process repeating periodically [H. Hotani, J. Mol. Biol. 156, 791 (1982)]. We propose a theory for this phenomenon based on a treatment of the flagellum as an elastic object with multiple stable configurations. The simplest possible implementation of the model accurately reproduces key features seen in experiment.
An Air-Stable Low-Bandgap n-Type Organic Polymer Semiconductor Exhibiting Selective Solubility in Perfluorinated Solvents

A thin-film transistor: An n-type polymer semiconductor, poly(2,3-bis(perfluorohexyl)thieno[3,4-b]pyrazine), was synthesized through a Pd-catalyzed polycondensation employing a perfluorinated multiphase solvent system. This is the first example of an n-type polymer semiconductor with exclusive solubility in fluorinated solvents. The fabrication of organic field effect transistors containing this new n-type polymer semiconductor is shown.
Topics on abelian spin models and related problems

In these notes, we discuss a selection of topics on several models of planar statistical mechanics. We consider the Ising, Potts, and more generally abelian spin models; the discrete Gaussian free field; the random cluster model; and the six-vertex model. Emphasis is put on duality, order, disorder and spinor variables, and on mappings between these models.
Epitaxial Films of Cobalt Disilicide (100) Evaporated Onto Si (100) from a Mixed Source

Thin films of (100) oriented CoSi2 have been electron beam evaporated onto Si(100) substrates from a mixed Co-Si target. A sharp c(2×2) low energy electron diffraction (LEED) pattern resulted after annealing the films to 800 °C. Extended x-ray absorption fine structure (EXAFS) of the film indicated the phase to be CoSi2 Quantitative x-ray photoelectron spectroscopy (XPS) analysis revealed the surface of the film to be slightly Si rich, indicating the Si terminated CoSi2 variant. Analysis of transmission electron microscope (TEM) diffraction patterns also provided evidence of the (100) orientation of the film.
Executing a program on the MIT tagged-token dataflow architecture

The MIT Tagged-Token Dataflow Project has an unconventional, but integrated approach to general-purpose high-performance parallel computing. Rather than extending conventional sequential languages, Id, a high-level language with fine-grained parallelism and determinacy implicit in its operational semantics, is used. Id programs are compiled to dynamic dataflow graphs, which constitute a parallel machine language. Dataflow graphs are directly executed on the MIT tagged-token dataglow architecture (TTDA), a multiprocessor architecture. An overview of current thinking on dataflow architecture is provided by describing example Id programs, their compilation to dataflow graphs, and their execution on the TTDA. Related work and the status of the project are described. >