Showing papers by "New York University published in 1986"
University of Miami1, New York University2, Stanford University3, University of Michigan4, George Washington University5, Indiana University6, University of Pittsburgh7, Queen's University8, North Shore-LIJ Health System9, Johns Hopkins University10, SUNY Downstate Medical Center11, University of Alabama at Birmingham12, University of Florida13, Harvard University14, Boston University15, Case Western Reserve University16, Washington University in St. Louis17, Menorah Medical Center18, Stony Brook University19, University of Kansas20
TL;DR: Variables from the medical history, physical examination, laboratory tests, and radiographs were used to develop sets of criteria that serve different investigative purposes and these proposed criteria utilize classification trees, or algorithms.
Abstract: For the purposes of classification, it should be specified whether osteoarthritis (OA) of the knee is of unknown origin (idiopathic, primary) or is related to a known medical condition or event (secondary). Clinical criteria for the classification of idiopathic OA of the knee were developed through a multicenter study group. Comparison diagnoses included rheumatoid arthritis and other painful conditions of the knee, exclusive of referred or para-articular pain. Variables from the medical history, physical examination, laboratory tests, and radiographs were used to develop sets of criteria that serve different investigative purposes. In contrast to prior criteria, these proposed criteria utilize classification trees, or algorithms.
6,160 citations
TL;DR: In this article, the effect of the bid-ask spread on asset pricing was studied and it was shown that market-observed expexted return is an increasing and concave function of the spread.
4,129 citations
TL;DR: In this article, the authors empirically tested whether different models are needed to predict the adoption of technical process innovations that contain a high degree of new knowledge radical innovations and a low degree of incremental innovations.
Abstract: This paper proposes and empirically tests whether different models are needed to predict the adoption of technical process innovations that contain a high degree of new knowledge radical innovations and a low degree of new knowledge incremental innovations. Results from a sample of 40 footwear manufacturers suggest that extensive knowledge depth measured by the number of technical specialists is important for the adoption of both innovation types. Larger firms are likely to have both more technical specialists and to adopt radical innovations. The study did not find associations between the adoption of either innovation type and decentralized decision making, managerial attitudes toward change, and exposure to external information. By implication, managers trying to encourage technical process innovation adoption need not be as concerned about modifying centralization of decision making, managerial attitudes and exposure to external information as would managers trying to encourage other types of innovation adoption, e.g., innovations in social services where these factors have been found to be important. Instead, investment in human capital in the form of technical specialists appears to be a major facilitator of technical process innovation adoption.
2,389 citations
TL;DR: The construct of prosocial organizational behavior is defined and 13 specific forms are described in this article, which vary according to whether they are functional or dysfunctional for organizational effectiveness, prescribed or not prescribed as part of one's organizational role, and directed toward an individual or organizational target.
Abstract: The construct of prosocial organizational behavior is defined and 13 specific forms are described. They vary according to whether they are functional or dysfunctional for organizational effectiveness, prescribed or not prescribed as part of one's organizational role, and directed toward an individual or organizational target. Potential predictors and determinants drawn from the social psychological literature suggest an agenda for research in organizational settings.
1,832 citations
TL;DR: As the conception of what marketing is has evolved, so must the methods of inquiry also evolve as discussed by the authors, and marketing now is viewed as a socially constructed enterprise. Thus, what is needed are inputs from inputs from th...
Abstract: As the conception of what marketing is has evolved, so must the methods of inquiry also evolve. Marketing now is viewed as a socially constructed enterprise. Thus, what is needed are inputs from th...
996 citations
TL;DR: The results demonstrate that user involvement in the development of information systems will enhance both system usage and the user's satisfaction with the system.
Abstract: "User involvement" in information system development is generally considered an important mechanism for improving system quality and ensuring successful system implementation. The common assumption that user involvement leads to system usage and/or information satisfaction is examined in a survey of 200 production managers. Alternative models exploring the causal ordering of the three variables are developed and tested via path analysis. The results demonstrate that user involvement in the development of information systems will enhance both system usage and the user's satisfaction with the system. Further, the study provides evidence that the user's satisfaction with the system will lead to greater system usage.
948 citations
TL;DR: The dispersion relations are solved for waves guided by a thin, lossy metal film surrounded by media of dielectric constant and both radiative waves can be interpreted as spatial transients, which could have physical significance near a transverse plane.
Abstract: The dispersion relations are solved for waves guided by a thin, lossy metal film surrounded by media of dielectric constant ${\ensuremath{\epsilon}}_{1}$ and ${\ensuremath{\epsilon}}_{3}$. For symmetric structures (${\ensuremath{\epsilon}}_{1}$=${\ensuremath{\epsilon}}_{3}$), there are the usual two Fano modes whose velocity and attenuation vary with film thickness. For very thin films, one of these modes can attain multicentimeter propagation distances when \ensuremath{\lambda}g1 \ensuremath{\mu}m. In addition, there are two leaky waves which correspond to waves localized at the ${\ensuremath{\epsilon}}_{1}$ (or ${\ensuremath{\epsilon}}_{3}$) dielectric-metal interface whose fields decay exponentially across the metal film and radiate an angular spectrum of plane waves into ${\ensuremath{\epsilon}}_{3}$ (or ${\ensuremath{\epsilon}}_{1}$, respectively). Both radiative waves can be interpreted as spatial transients, which could have physical significance near a transverse plane. When ${\ensuremath{\epsilon}}_{1}$\ensuremath{
e}${\ensuremath{\epsilon}}_{3}$, there are still four distinct solutions for a given film thickness, two radiative and two nonradiative. For lossy films, there are always two nonradiative solutions for thick enough films. As the thickness goes to infinity, the four solutions reduce to two waves, each radiative and nonradiative pair becoming degenerate. The physical interpretation of these solutions and their dependence on dielectric constant and wavelength are discussed.
936 citations
TL;DR: In this article, the authors proposed diagnostic criteria and measures of clinical change for age-associated memory impairment and developed a set of diagnostic criteria based on the report of a national institute of mental health work group.
Abstract: (1986). Age‐associated memory impairment: Proposed diagnostic criteria and measures of clinical change — report of a national institute of mental health work group. Developmental Neuropsychology: Vol. 2, No. 4, pp. 261-276.
919 citations
TL;DR: In this paper, a functional central limit theorem for additive functionals of stationary reversible ergodic Markov chains was proved under virtually no assumptions other than the necessary ones, and they used these results to study the asymptotic behavior of a tagged particle in an infinite particle system performing simple excluded random walk.
Abstract: We prove a functional central limit theorem for additive functionals of stationary reversible ergodic Markov chains under virtually no assumptions other than the necessary ones. We use these results to study the asymptotic behavior of a tagged particle in an infinite particle system performing simple excluded random walk.
909 citations
TL;DR: To understand the role of proteinases in tumor invasion, the effects of inhibitors of metallo-, serine-, and cysteine-proteinases on this process were studied using 125I-iododeoxyuridine-labeled B16/BL6 cells grown on human amnion basement membrane.
785 citations
TL;DR: It is suggested that neurotransmitters may rapidly activate specific gene transcription in nondividing neuronally differentiated cells and a functional role for neurotransmitter induction of c-fos and actin expression in the nervous system is suggested.
Abstract: Cholinergic agonists rapidly and transiently induced transcription of the c-fos protooncogene and one or more actin genes in neuronally differentiated PC12 cells. Transcription was activated within minutes after stimulation of the nicotinic acetylcholine receptor and required an influx of extracellular Ca2+ ions through voltage-sensitive calcium channels. Nicotine activation proceeded by a different pathway from activation by nerve growth factor, whose stimulation of these genes is independent of extracellular Ca2+ ions. These findings suggest that neurotransmitters may rapidly activate specific gene transcription in nondividing neuronally differentiated cells. They also suggest a functional role for neurotransmitter induction of c-fos and actin expression in the nervous system.
TL;DR: In this paper, the authors examined the distribution of the values of patent rights in the United Kingdom, France, and Germany during the post-1950 period, based on the behavior of patentees with respect to payment of renewal fees on their patents.
Abstract: This paper examines the distribution of the values of patent rights in the United Kingdom, France, and Germany during the post-1950 period. These values are inferred from the behavior of patentees with respect to payment of renewal fees on their patents. A simple economic model of renewal decisions is combined with data on the proportion of patents renewed at alternative ages and the renewal fee schedules to produce estimates of the distribution (and the total) value of patent rights in these countries. Moreover, the data indicate that there have been changes in the value distribution, and we follow these changes over the period. The empirical results of particular interest concern: the total value of patent rights and the relationship between changes in it and changes in the quantity of patents, the skew in the distribution of patent values, and the rate of obsolescence on the returns to patents.
TL;DR: It is suggested that middle managers with low or negative commitment to the strategies formulated by senior management create significant obstacles to effective implementation.
Abstract: This article suggests that middle managers with low or negative commitment to the strategies formulated by senior management create significant obstacles to effective implementation.
TL;DR: It is demonstrated that purified E. coli-derived recombinant human TNF inhibits encephalomyocarditis virus replication in "aged" human fibroblasts, suggesting that IFN-beta 2 has biological functions distinct from the other interferons.
TL;DR: This article used newsstand prices of American magazines to investigate the determinants of the frequency of nominal price change and concluded that higher inflation leads to more frequent price adjustment and that the real cost of price changes varies with the size of a real price change.
TL;DR: If neutrinos are Majorana particles in a ''see-saw'' scheme the couplings photino--lepton--Scalar-lepton lead to sizable rates for the processesMuon and electron lepton-number nonconservation due to renormalization effects of the scalar-Lepton mass matrix in spontaneously broken N = 1 supergravity theories.
Abstract: We discuss muon and electron lepton-number nonconservation due to renormalization effects of the scalar-lepton mass matrix in spontaneously broken $N=1$ supergravity theories. Differently from the case of massless or Dirac neutrinos, we find that if neutrinos are Majorana particles in a "seesaw" scheme the couplings photino-lepton-scalar-lepton lead to sizable rates for the processes $\ensuremath{\mu}\ensuremath{\rightarrow}e\ensuremath{\gamma}$ and $\ensuremath{\mu}+\mathrm{nucleus}\ensuremath{\rightarrow}e+\mathrm{nucleus}$. We discuss the constraints derived from the present experimental bounds.
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TL;DR: In this article, the authors present a survey of recent lterature that has analyzed the nature of credit relations between developed and developing countries, focusing on the problem of enforcing the two sides of a loan contract.
Abstract: This paper attempts to survey, and to put into perspective, recent lterature that has analyzed the nature of credit relations between developed and developing countries.This analysis has made use of recent advances in the economics of information and strategic interaction. Traditional concepts of solvency and liquidity are of little help in understanding problems of soverign debt. Creditors do not have the means to seize the assets of a borrower in default. Hence the borrower who is expected eventually to repay his debts should be able to borrow to meet any current debt-service obligations. A problem that is essential to a theory of international lending is that of enforcement. The difficulty is one of ensuring that the two sides of a loan contract adhere to it, in particular that the borrower repays the lender and the lenders can commit themselves to penalize the borrower if he does not.
TL;DR: QF categorization provides a relatively insensitive measure of individual differences in drinking behavior as compared to TL-derived data, which can be used to generate a variety of potentially useful dependent variables, whereas the QF method generates a single variable.
TL;DR: The results indicate that growth factors modulate the proteolytic balance of cultured cells by altering the amounts of PAs and their inhibitors.
Abstract: Cultured human embryonic lung fibroblasts were used as a model to study the effects of transforming growth factor-beta (TGF beta) on the plasminogen activator (PA) activity released by nontumorigenic cells into the culture medium. The cells were exposed to TGF beta under serum-free conditions, and the changes in PA activity and protein metabolism were analyzed by caseinolysis-in-agar assays, zymography, and polypeptide analysis. Treatment of the cells with TGF beta caused a significant decrease in the PA activity of the culture medium as analyzed by the caseinolysis-in-agar assays. The quantitatively most prominent effect of TGF beta on confluent cultures of cells was the induction of an Mr 47,000 protein, as detected by metabolic labeling. The Mr 47,000 protein was a PA inhibitor as judged by reverse zymography. It was antigenically related to a PA inhibitor secreted by HT-1080 tumor cells as demonstrated with monoclonal antibodies. The induced Mr 47,000 inhibitor was deposited into the growth substratum of the cells, as detected by metabolic labeling, immunoblotting analysis, and reverse zymography assays of extracellular matrix preparations. TGF beta also decreased the amounts of urokinase-type and tissue-type PAs accumulated in the conditioned medium, as detected by zymography. Epidermal growth factor antagonized the inhibitory effects of TGF beta by enhancing the amounts of the PAs. These results indicate that growth factors modulate the proteolytic balance of cultured cells by altering the amounts of PAs and their inhibitors.
TL;DR: In this paper, the authors examined Rosenhead's point-vortex approximation and sought to understand better the source of this difficulty, using discrete Fourier analysis, it was shown that perturbations introduced spuriously by computer roundoff error are responsible for the irregular point vortex motion that occurs at a smaller time as the number of points is increased, this source of computational error is controlled here by using either higher precision arithmetic or a new filtering technique.
Abstract: The initial-value problem for perturbations of a flat, constant-strength vortex sheet is linearly ill posed in the sense of Hadamard, owing to Kelvin-Helmholtz instability. Previous numerical studies of this problem have experienced difficulty in converging when the mesh was refined. The present work examines Rosenhead’s point-vortex approximation and seeks to understand better the source of this difficulty. Using discrete Fourier analysis, it is shown that perturbations introduced spuriously by computer roundoff error are responsible for the irregular point-vortex motion that occurs at a smaller time as the number of points is increased. This source of computational error is controlled here by using either higher precision arithmetic or a new filtering technique. Computations are presented which use a linear-theory growing eigenfunction of small amplitude/wavelength ratio as the initial perturbation. The results indicate the formation of a singularity in the vortex sheet at a finite time as previously found for other initial data by Moore and Meiron, Baker & Orszag using different techniques of analysis. Numerical evidence suggests that the point vortex approximation converges up to but not beyond the time of singularity formation in the vortex sheet. For large enough initial amplitude, two singularities appear along the sheet at the critical time.
TL;DR: On presente une theorie pour l'instabilite non visqueux d'une onde courte tridimensionnelle de l'ecoulement elliptique bidimensionnels simple.
Abstract: On presente une theorie pour l'instabilite non visqueux d'une onde courte tridimensionnelle de l'ecoulement elliptique bidimensionnel simple
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TL;DR: In this article, the authors estimate a model of production and investment based on the theory of dynamic duality and are particularly interested in the effects of R&D spillovers and in calculating the social and private rates of return.
Abstract: In this paper we estimate a model of production and investment based on the theory of dynamic duality and are particularly Interested in the effects of R&D spillovers and in calculating the social and private rates of return We identify and estimate three effects associated with the intraindustry R&D spillover First, costs decline as knowledge expands for the externality-receiving firms Second, production structures are affected, as factor demands change in response to the spillover Third, the rates of capital accumulation are affected by the R&D spillover These cost-reducing, factor-biasing and capital adjustment effects of the spillover are estimated for four industries The existence of R&D spillovers implies that the social and private rates of return to R&D capital differ We estimate that the social return exceeds the private return in each industry However, there is significant variation across industries in the differential between the social and private rates of return
TL;DR: A lower bound on the length of paths generated by any algorithm operating with uncertainty is formulated, and two nonheuristic path planning algorithms are described.
Abstract: The problem of path planning is studied for the case of a mobile robot moving in an environment filled with obstacles whose shape and positions are not known. Under the accepted model, the automaton knows its own and the target coordinates, and has a "sensory" feedback which provides it with local information on its immediate surroundings. Ibis information is shown to be sufficient to guarantee reaching a global objective (the target), while generating reasonable (if not optimal) paths. A lower bound on the length of paths generated by any algorithm operating with uncertainty is formulated, and two nonheuristic path planning algorithms are described. In the algorithms, motion planning is done continuously (dynamically), based on the automaton's current position and on its feedback. The effect of additional sources of information (e.g., from a vision sensor) on the outlined approach is discussed.
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24 Oct 1986TL;DR: SETL improves programmer speed and pro ductivity significantly, and also enhances program clarity and readability, and the classroom consequence is that students, freed of some of the burden of petty programming detail, can advance their knowledge of significant algorithms and of broader strategic issues in program development more rapidly than with more conventional programming languages.
Abstract: The programming language SETL is a relatively new member of the so-called "very-high-level" class of languages, some of whose other well-known mem bers are LISP, APL, SNOBOL, and PROLOG. These languages all aim to reduce the cost of programming, recognized today as a main obstacle to future progress in the computer field, by allowing direct manipulation of large composite objects, considerably more complex than the integers, strings, etc., available in such well-known mainstream languages as PASCAL, PL/I, ALGOL, and Ada. For this purpose, LISP introduces structured lists as data objects, APL introduces vectors and matrices, and SETL introduces the objects characteristic for it, namely general finite sets and maps. The direct availability of these abstract, composite objects, and of powerful mathematical operations upon them, improves programmer speed and pro ductivity significantly, and also enhances program clarity and readability. The classroom consequence is that students, freed of some of the burden of petty programming detail, can advance their knowledge of significant algorithms and of broader strategic issues in program development more rapidly than with more conventional programming languages."
TL;DR: Different genetic mechanisms may be involved in chromosomal translocation/c-myc activation, and these differences may be a function of differences in the stage of differentiation of eBL versus sBL.
Abstract: We have examined the position of the chromosomal breakpoint relative to the human c-myc gene (MYC) and the presence of other structural alterations of the same locus in 19 fresh samples of Burkitt lymphoma (BL) and 13 BL-derived cell lines. This panel includes the two pathogenetic forms of BL: the endemic (African-type) BL (eBL) and sporadic (American-type) BL (sBL). In all cases tested, including fresh samples and cell lines, structural alterations of the 5' portion of the gene were detected, suggesting that they may be necessary for c-myc activation. However, the site of chromosomal breakpoint and the type of structural alterations differ in eBL and sBL. In 16 of 18 sBL cases, chromosomal translocation truncates the gene within a 5' region that includes the first intron, the first exon, and 5' flanking sequences. Conversely, in 14 of 14 eBL samples, the chromosomal breakpoint is located outside the c-myc locus, yet the same 5' sequences are affected by several mutations identifiable by restriction enzyme polymorphisms. Different genetic mechanisms may therefore be involved in chromosomal translocation/c-myc activation, and these differences may be a function of differences in the stage of differentiation of eBL versus sBL.
TL;DR: Results suggest that immunologically induced interferon may be involved in controlling malaria infection under natural conditions.
Abstract: A specific DNA probe was used to study the effect of recombinant rat, mouse, and human gamma-interferon (gamma-IFN) on the course of sporozoite-induced malaria infections. In mice and rats infected with sporozoites of Plasmodium berghei, mouse and rat gamma-IFN's strongly inhibited the development of the exoerythrocytic forms in the liver liver cells of the hosts, but not the development of the erythrocytic stages. The degree of inhibition of the exoerythrocytic forms was proportional to the dose of gamma-IFN administered, but was independent of the number of sporozoites used for challenge. A 30 percent reduction in the development of exoerythrocytic forms in rat liver was achieved when 150 units (about 15 nanograms of protein) of rat gamma-IFN were injected a few hours before sporozoite challenge; the reduction was 90 percent or more with higher doses of gamma-IFN. The effect was less pronounced if the gamma-IFN was administered 18 hours before or a few hours after challenge. Human gamma-IFN also diminished the parasitemia in chimpanzees infected with sporozoites of the human malaria parasite Plasmodium vivax. The target of gamma-IFN activity may be the infected hepatocytes themselves, as shown by in vitro experiments in which small doses of the human lymphokine inhibited the development of exoerythrocytic forms of Plasmodium berghei in a human hepatoma cell line. These results suggest that immunologically induced interferon may be involved in controlling malaria infection under natural conditions.
TL;DR: Certain tumor characteristics were associated with a better prognosis, e.g., size below 5 cm in diameter, lack of invasion of collecting system, perirenal fat or regional lymph nodes, and predominance of clear or granular cells growing into a recognizable histologic pattern.
TL;DR: The manner in which cytolytic peptides interact with plasma membranes of eukaryotic cells, particularly the membranes of erythrocytes, has been discussed with emphasis on melittin, thiolactivated lysins and staphylococcal alpha-toxin.
TL;DR: It is reported that tumor necrosis factor (TNF) provokes superoxide anion generation from human neutrophils and movements of intracellular calcium may mediate the TNF-stimulated superoxideAnion generation.
TL;DR: In this paper, the degree of centralization inherent in the headquarters-foreign subsidiary relationship varies in response to a variety of company-wide and subsidiary level conditions, and several new contingency patterns are identified.
Abstract: Research to date on centralization in MNCs has produced many inconsistent findings. The present study attempts to add clarity to the situation by re-testing many of the existing hypotheses with data from a recent study of centralization in 50 large US, UK and European MNCs. It examines how the degree of centralization inherent in the headquarters-foreign subsidiary relationship varies in response to a variety of company-wide and subsidiary level conditions. The influence of company-wide conditions on centralization appears to be much clearer than the influence of subsidiary-level conditions. The study also identifies several new contingency patterns that appear to be at work in MNCs today.