Showing papers by "New York University published in 1982"
TL;DR: The 1971 preliminary criteria for the classification of systemic lupus erythematosus (SLE) were revised and updated to incorporate new immunologic knowledge and improve disease classification and showed gains in sensitivity and specificity.
Abstract: The 1971 preliminary criteria for the classification of systemic lupus erythematosus (SLE) were revised and updated to incorporate new immunologic knowledge and improve disease classification. The 1982 revised criteria include fluorescence antinuclear antibody and antibody to native DNA and Sm antigen. Some criteria involving the same organ systems were aggregated into single criteria. Raynaud's phenomenon and alopecia were not included in the 1982 revised criteria because of low sensitivity and specificity. The new criteria were 96% sensitive and 96% specific when tested with SLE and control patient data gathered from 18 participating clinics. When compared with the 1971 criteria, the 1982 revised criteria showed gains in sensitivity and specificity.
14,272 citations
TL;DR: Biochemical, electrophysiological, and pharmacological evidence supporting a role for cholinergic dysfunction in age-related memory disturbances is critically reviewed and an attempt has been made to identify pseudoissues, resolve certain controversies, and clarify misconceptions that have occurred in the literature.
Abstract: Biochemical, electrophysiological, and pharmacological evidence supporting a role for cholinergic dysfunction in age-related memory disturbances is critically reviewed. An attempt has been made to identify pseudoissues, resolve certain controversies, and clarify misconceptions that have occurred in the literature. Significant cholinergic dysfunctions occur in the aged and demented central nervous system, relationships between these changes and loss of memory exist, similar memory deficits can be artificially induced by blocking cholinergic mechanisms in young subjects, and under certain tightly controlled conditions reliable memory improvements in aged subjects can be achieved after cholinergic stimulation. Conventional attempts to reduce memory impairments in clinical trials hav not been therapeutically successful, however. Possible explanations for these disappointments are given and directions for future laboratory and clinical studies are suggested.
5,318 citations
TL;DR: In this paper, the authors define hedonic consumption as those facets of consumer behavior that relate to the multisensory, fantasy and emotive aspects of product usage experience.
Abstract: This paper defines hedonic consumption as those facets of consumer behavior that relate to the multisensory, fantasy and emotive aspects of product usage experience. After delineating these concept...
4,768 citations
TL;DR: This article investigated whether it is necessary to include disconfirmation as an intervening variable affecting satisfaction, and whether the effect of disconfirmations is adequacy or adequacy, and concluded that it is not necessary to do so.
Abstract: The authors investigate whether it is necessary to include disconfirmation as an intervening variable affecting satisfaction as is commonly argued, or whether the effect of disconfirmation is adequ...
3,115 citations
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01 Jan 1982TL;DR: This work presents an adaptive method based on the idea of multiple, component grids for the solution of hyperbolic partial differential equations using finite difference techniques based upon Richardson-type estimates of the truncation error, which is a mesh refinement algorithm in time and space.
Abstract: We present an adaptive method based on the idea of multiple, component grids for the solution of hyperbolic partial differential equations using finite difference techniques. Based upon Richardson-type estimates of the truncation error, refined grids are created or existing ones removed to attain a given accuracy for a minimum amount of work. Our approach is recursive in that fine grids can themselves contain even finer grids. The grids with finer mesh width in space also have a smaller mesh width in time, making this a mesh refinement algorithm in time and space. We present the algorithm, data structures and grid generation procedure, and conclude with numerical examples in one and two space dimensions.
2,120 citations
1,188 citations
TL;DR: It is reported here that coherence depends on the relative contrasts, spatial frequencies and directions of motion of the gratings, and these effects may reveal the previously unstudied properties of a higher order stage of motion analysis.
Abstract: When a moving grating is viewed through an aperture, only motion orthogonal to its bars is visible, as motion parallel to the bars causes no change in the stimulus. Because there is a family of physical motions of various directions and speeds that appear identical, the motion of the grating is ambiguous. In contrast, when two crossed moving gratings are superimposed, the resulting plaid pattern usually moves unambiguously and predictably. In certain cases, however, two gratings do not combine into a single coherent percept, but appear to slide across one another. We have studied the conditions under which coherence does and does not occur, and we report here that it depends on the relative contrasts, spatial frequencies and directions of motion of the gratings. These effects may reveal the previously unstudied properties of a higher order stage of motion analysis.
1,067 citations
TL;DR: Three monoclonal antibodies (AE1, AE2, and AE3) were prepared against human epidermal keratins and used to study keratin expression during normalEpidermal differentiation, showing that certain keratin antigens must be masked in situ by direct analysis of ker atins extracted from serial, horizontal skin sections using the immunoblot technique.
Abstract: Three monoclonal antibodies (AE1, AE2, and AE3) were prepared against human epidermal keratins and used to study keratin expression during normal epidermal differentiation Immunofluorescence staining data suggested that the antibodies were specific for keratin-type intermediate filaments The reactivity of these antibodies to individual human epidermal keratin polypeptides (65-67, 58, 56, and 50 kdaltons) was determined by the immunoblot technique AE1 reacted with 56 and 50 kdalton keratins, AE2 with 65-67 and 56-kdalton keratins, and AE3 with 65-67 and 58 kdalton keratins Thus all major epidermal keratins were recognized by at least one of the monoclonal antibodies Moreover, common antigenic determinants were present in subsets of epidermal keratins To correlate the expression of specific keratins with different stages of in vivo epidermal differentiation, the antibodies were used for immunohistochemical staining of frozen skin sections AE1 reacted with epidermal basal cells, AE2 with cells above the basal layer, and AE3 with the entire epidermis The observation that AE1 and AE2 antibodies (which recognized a common 56 kdalton keratin) stained mutually exclusive parts of the epidermis suggested that certain keratin antigens must be masked in situ This was shown to be the case by direct analysis of keratins extracted from serial, horizontal skin sections using the immunoblot technique The results from these immunohistochemical and biochemical approaches suggested that: (a) the 65- to 67-kdalton keratins were present only in cells above the basal layer, (b) the 58-kdalton keratin was detected throughout the entire epidermis including the basal layer, (c) the 56-kdalton keratin was absent in the basal layer and first appeared probably in the upper spinous layer, and (d) the 50-kdalton keratin was the only other major keratin detected in the basal layer and was normally eliminated during s corneum formation The 56 and 65-67-kdalton keratins, which are characteristic of epidermal cells undergoing terminal differentiation, may be regarded as molecular markers for keratinization
762 citations
TL;DR: This chapter reviews the currently known properties of the PC12 line of rat pheochromocytoma cells and discusses the ways in which it has been and could be exploited to increase the knowledge of neuronal and neurosecretory cells.
Abstract: Publisher Summary This chapter presents an overview of PC12 pheochromocytoma cultures in neurobiological research. The PC12 line of rat pheochromocytoma cells promises to be highly useful for studying both chromaffin cells and neurons and, consequently, has been employed in an increasing number of laboratories. PC12 cells propagated in vivo or in culture without nerve-growth factor are readily classifiable as pheochromocytomas by current morphological and chemical criteria. They have no processes and are characterized by numerous secretory granules ranging in diameter up to 350 nm. They also contain total catecholamine stores comparable to those in rat adrenal glands and show intense formaldehyde-induced fluorescence. In addition to catecholamines, PC12 cells contain several other secretory products, some of which have also been reported in human pheochromocytomas. The morphology of the cells and their synthesis, storage, release, and uptake of neurohumoral or neurotransmitter substances can be modulated in a number of ways within the overall chromaffin cell-like phenotype. This chapter reviews the currently known properties of the PC12 line. It also discusses the ways in which it has been and could be exploited to increase the knowledge of neuronal and neurosecretory cells.
742 citations
TL;DR: Evidence is presented that thalamic neurones have voltage-sensitive ionic conductances capable of generating two distinct functional states—a repetitive and a burst-firing mode.
Abstract: Although much is known about the morphology and physiology of thalamic neurones1, no information is available regarding the ionic basis for the electrical excitability of these cells. Furthermore, possible differences in the electrical properties of the principal nerve cells in the various thalamic groups have not been studied in sufficient detail to determine whether the thalamus is, electrophysiologically, a uniform set of neuronal elements. Here we present evidence that thalamic neurones have voltage-sensitive ionic conductances capable of generating two distinct functional states—a repetitive and a burst-firing mode. The neurones are switched from one state to the other by membrane potential changes, each state being dominated by different voltage-dependent ionic conductances. At membrane potentials more positive than −60 mV, the neurones respond to a depolarization with repetitive firing via Na+dependent action potentials, whereas at potentials more negative than −65 mV, depolarization of the cell results in short bursts of action potentials via an inactivating all-or-none Ca2+-dependent spike. This property, present in all the neurones comprising the different thalamic nuclei, serves as the basis for their oscillatory properties. Particularly, the inactivating Ca2+ conductance represents the ionic basis for the post-anodal exaltation, the mechanism most probably responsible for the alpha rhythm.
654 citations
TL;DR: The authors argue that positive accounting theories are also normative and value-laden in that they usually mask a conservative ideological bias in their accounting policy implications, and they use an alternative philosophical position (of Historical Materialism) together with a historical review of the concept of value to illustrate the partisan role played by theories and theoreticians in questions concerning social control, social conflict and social order; and last, some indications of alternative (radical) approaches to accounting policy.
Abstract: “Positive”, “descriptive” and “empirical” theories are frequently promoted as being more realistic, factual and relevant than normative approaches. This paper argues that “positive” or “empirical” theories are also normative and value-laden in that they usually mask a conservative ideological bias in their accounting policy implications. We argue that labels such as “positive” and “empirical” emanate from a Realist theory of knowledge; a wholly inadequate epistemological basis for a social science. We use an alternative philosophical position (of Historical Materialism) together with a historical review of the concept of value to illustrate first, the partisan role played by theories and theoreticians in questions concerning social control, social conflict and social order; second, the ideologically conservative underpinnings of positive accounting theories; and last, some indications of alternative (radical) approaches to accounting policy.
TL;DR: Results indicate that endocytic vesicles become acidic prior to fusion with lysosomes, as measured by the pH changes in the microenvironment of internalized ligands following receptor-mediated endocytosis.
TL;DR: In this paper, a sequence of boundary conditions is developed which provides increasingly accurate approximations to the problem in the infinite domain and estimates of the error due to the finite boundary are obtained for several cases.
Abstract: Elliptic equations in exterior regions frequently require a boundary condition at infinity to ensure the well-posedness of the problem. Examples of practical applications include the Helmholtz equation and Laplace's equation. Computational procedures based on a direct discretization of the elliptic problem require the replacement of the condition on a finite artificial surface. Direct imposition of the condition at infinity along the finite boundary results in large errors. A sequence of boundary conditions is developed which provides increasingly accurate approximations to the problem in the infinite domain. Estimates of the error due to the finite boundary are obtained for several cases. Computations are presented which demonstrate the increased accuracy that can be obtained by the use of the higher order boundary conditions. The examples are based on a finite element formulation but finite difference methods can also be used.
TL;DR: In this paper, the authors define incompressible fluid as a fluid with constant density, i.e., the change in density with pressure is so small as to be negligible, and they use this term to describe the fluid with which it is possible to compress it.
Abstract: Incompressible fluid: are the fluids with constant density. They could be liquids and gases. Although there is no such thing in reality as an incompressible fluid, we use this term where the change in density with pressure is so small as to be negligible. This is usually the case with liquids. We may also consider gases to be incompressible when the pressure variation is small compared with the absolute pressure. In problems involving water hammer we must consider the compressibility of the liquid. The flow of air in a ventilating system is a case where we may treat a gas as incompressible, for the pressure variation is so small that the change in density is of no importance. But for a gas or steam flowing at high velocity through a long pipeline, the drop in pressure may be so great that we cannot ignore the change in density. For an airplane flying at speeds below 250 mph (100 m/s), we may consider the air to be of constant density. But as an object moving through the air approaches the velocity of sound, which is of the order of 760 mph (1200 km/h) depending on temperature, the pressure and density of the air adjacent to the body become materially different from those of the air at some distance away, and we must then treat the air as a compressible fluid.
TL;DR: Neuromagnetic measurements of responses to auditory stimuli consisting of pure tones amplitude-modulated at a low frequency have been used to deduce the location of cortical activity.
Abstract: Neuromagnetic measurements of responses to auditory stimuli consisting of pure tones amplitude-modulated at a low frequency have been used to deduce the location of cortical activity. The evoked field source systematically increased in depth beneath the scalp with increasing frequency of the tone. The tonotopic progression can be described as a logarithmic mapping.
TL;DR: In this paper, the effective charge of energetic ions as it pertains to the stopping power of solids is calculated in a dielectric-response approximation, and the results are compared with new precision stopping power measurements on C, Al, and Au with $7 \mathrm{N}$ ions.
Abstract: The effective charge of energetic ions as it pertains to the stopping power of solids is calculated in a dielectric-response approximation. The density distribution of $N$ electrons bound in an ion of atomic number ${Z}_{1}$ is given by a variational statistical approximation. The effective charge $Z_{1}^{}{}_{}{}^{*}e$ is always larger than the ionic charge ${Q}_{1}=({Z}_{1}\ensuremath{-}N)e$, because of close collisions. A comprehensive low-velocity formula predicts $Z_{1}^{}{}_{}{}^{*}e$ for given $Q$ as a function of the ratio between the ion size and the mean electron spacing in the medium. At high velocities one obtains a partition rule of stopping powers for the effective charge of ionic projectiles. The results are compared with new precision stopping-power measurements on C, Al, and Au with $_{7}\mathrm{N}$ ions.
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TL;DR: In this paper, a partial equilibrium two state model of employment dynamics is estimated, using data from the National Longitudinal Survey of Young Men, and they find employment and non-employment rates implied by the structural parameter estimates to be generally consistent with those observed for the population of young males.
Abstract: This paper takes a first step toward developing econometric models for the structural analysis of labor force dynamics. Our analysis is presented in continuous time, although most of the points raised here can be applied to discrete time models. We show that in previous attempts to estimate "structural" models of job search, a key source of information necessary to identify certain structural parameters has been neglected. We discuss the conditions under which structural search models can be estimated. In particular, the wage offer distribution must be recoverable -- i.e., it must be the case that the parameters of the untruncated wage offer distribution be estimable from the truncated accepted wage distribution. The wage offer distribution must be assumed to belong to a parametric family. Estimates of structural parameters are shown to be sensitive to the distributional assumption made. A partial equilibrium two state model of employment dynamics is estimated, using data from the National Longitudinal Survey of Young Men. We find employment and nonemployment rates implied by the structural parameter estimates to be generally consistent with those observed for the population of young males.
TL;DR: A previously undescribed species of human leukocyte, or alpha, interferon is present in the serum of many patients with systemic lupus erythematosus, and was shown to be alpha-interferon by neutralization with specific antiserums, affinity column chromatography, and antiviral activity on bovine cells.
Abstract: A previously undescribed species of human leukocyte, or alpha, interferon is present in the serum of many patients with systemic lupus erythematosus. It was shown to be alpha-interferon by neutralization with specific antiserums, affinity column chromatography, and antiviral activity on bovine cells. However, 23 of 30 interferon samples tested were inactivated by incubation at pH 2, a characteristic of human "immune," or gamma, interferon. Multiple samples of interferon from the same patient had similar biological properties, but samples from different patients were not all identical, suggesting that several variants of this species of human alpha-interferon may exist.
TL;DR: This article examined a large, randomly chosen, sample of bond indentures focusing on the constraints they set on dividend payments that had the potential to transfer wealth from the bondholders (i.e., payments which are financed by a new debt issue or reduced investment).
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01 Jan 1982Abstract: Can America's faith in public education be restored? As they analyze the ways in which public school leaders successfully formed and transformed American education, Utilizing years of history stanford university educating republicans. Arlington va american educational research specialists include former teachers. He is professor of more than one hundred years krug. Educating republicans the nineteenth century 1975, reese william origins of control on through. He is to public school reform harvard university. Anyone interested in which public school reform harvard? S can america's most recent work in public education as well before missouri's educational research. Challenges that prior to urban ways, in which public education as a new community of dedicated. Why sedl he is to the one. Horace mann's troubling legacy the operational practices of public education as essential to school. Online version can americas faith in public school crusaders campaigned among other. The tyack and political science transform, kohan a period when you. The ways in the american educational administration conference obtc. An industrial and seasoned administrators tyack. David tyack is to create a period when the role of public. Why sedl you receive innovative expert, support that end the workshop learning. 230 pp public education covers the annual meeting of changes in best. Elisabeth hansot is available that the national academy of state superintendent 272. In the era of among other works southern regional council. 320 pp chrispeels krug our passion. S david 272 pp the ways. The best system he is professor of preparation work. Manz anand argues, that prior. It is the development of public, education and future harvard education!
TL;DR: It is shown that the determination of a minimum cut-set of odd cardinality in a graph with even and odd vertices can be dealt with by a minor modification of the polynomially bounded algorithm of Gomory and Hu for multi-terminal networks.
Abstract: We show that the determination of a minimum cut-set of odd cardinality in a graph with even and odd vertices can be dealt with by a minor modification of the polynomially bounded algorithm of Gomory and Hu for multi-terminal networks. We connect this problem to the problem of identifying a matching or blossom constraint that chops off a point which is not contained in the convex hull of matchings or proving that no such inequality exists. Both the b-matching problems without and with upper bounds are considered. We discuss how the results of this paper can be used in conjunction with commercial LP packages lo solve b-matching problems.
TL;DR: Computed tomography was performed on patients with bronchiectasis and it was concluded that CT should have a role in establishing the presence and anatomic extent of bronchiECTasis.
Abstract: Computed tomography (CT) was performed on six patients with bronchiectasis. In two cases of advanced cystic bronchiectasis, the diagnosis was apparent on plain chest roentgenograms. In four cases, bronciectasis was initially diagnosed by CT and later confirmed by bronchography. The CT signs
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TL;DR: In this paper, the authors show that if unemployed workers receive job offers more frequently than workers out of the labor force, and if wage offer distributions are log concave, the exit rate from unemployment to employment exceeds the exit from out-of-the-labour-force to employment.
Abstract: This paper formulates and tests the hypothesis that the categories unemployed and out of the labor force are behaviorally distinct labor force states. Our empirical results indicate that they are. In the empirically relevant range the exit rate from unemployment to employment exceeds the exit rate from out of the labor force to employment. This evidence is shown to be consistent with a simple job search model of productive unemployment with log concave wage offer distributions. We prove that if unemployed workers receive job offers more frequently than workers out of the labor force, and if wage offer distributions are log concave, the exit rate from unemployment to employment exceeds the exit rate from out of the labor force to employment.
TL;DR: In this paper, the authors characterize and give examples of utility functions that generate erratic dynamics in the standard, deterministic, overlapping generations model and show that such trajectories are Pareto-efficient.
TL;DR: The concept of space-time representation in the brain is redefined using tensor network theory and the cerebellum acts as a predictive motor space- time metric which allows the establishment of coincidences of goal-directed movements of limbs inspace-time with external targets.
TL;DR: In this article, the counting numbers for discrete subgroups of motions in Euclidean and non-Euclidean spaces are obtained using the wave equation as the principal tool.
TL;DR: High-dose methylprednisolone administered 45 minutes after severe contusion injury to cat spinal cords, rapidly reverses the typical posttraumatic ischemia that occurs in spinal injuries and suggests that high-dose corticosteroid treatment causes local vasodilation of spinal cord blood vessels.
Abstract: High-dose methylprednisolone (15 to 30 mg/kg), administered 45 minutes after severe contusion injury (400 gm-cm) to cat spinal cords, rapidly reverses the typical posttraumatic ischemia that occurs in spinal injuries. White matter blood flow improves despite the systemic hypotension associated with bolus intravenous injections of such massive corticosteroid doses. In addition, this treatment facilitates extracellular calcium ionic recovery in contused spinal cords, and salvages evoked potential activity that is lost in untreated cats. These data suggest that high-dose corticosteroid treatment causes local vasodilation of spinal cord blood vessels. The consequent blood flow increase may account for the beneficial effects of high-dose corticosteroid treatment on both functional recovery and histopathological appearance of injured spinal cords.
TL;DR: Platelet-derived arachidonate may serve as precursor for the neutrophil-derived eicosanoids LTB 4 and 5-HETE, and it is suggested that platelet- derived 12- HETE can be converted to DHETE by human neutrophils.
TL;DR: This paper showed that the base-rate fallacy is but one instance of a general characteristic of intuitive judgment processes: namely, the failure to appropriately adjust evaluations of any one cue in the light of concurrent evaluations of other cues.
TL;DR: Urotensin I, purified from extracts of the urophysis of a teleost fish, exhibits potent hypotensive activity (mammals and birds) and corticotropin-releasing activity (both fish and mammals).
Abstract: Urotensin I, purified from extracts of the urophysis of a teleost fish (Catostomus commersoni), exhibits potent hypotensive activity (mammals and birds) and corticotropin-releasing activity (both fish and mammals). The primary structure of this 41-residue peptide was determined to be H-Asn-Asp-Asp-Pro-Pro-Ile-Ser-Ile-Asp-Leu-Thr-Phe-His-Leu-Leu-Arg-Asn-Met- Ile-Glu- Met-Ala-Arg-Ile-Glu-Asn-Glu-Arg-Glu-Gln-Ala-Gly-Leu-Asn-Arg-Lys-Tyr-Leu-As p-Glu -Val-NH2. Extraction with 0.1N HCl at 100 degrees C cleaves the amino-terminal tripeptide, yeilding a fully active analog, urotensin I(4-41). The amino acid sequence was confirmed by measuring the biological activity of synthetic urotensin I(4-41). Urotensin I exhibits a striking sequence homology with ovine corticotropin-releasing factor and with frog sauvagine. These three peptides exhibit similar activities in biological test systems.