Showing papers by "New York University published in 1985"

A Role Theory Perspective on Dyadic Interactions: The Service Encounter:

Abstract: This article proposes that the dyadic interaction between a service provider and a customer is an important determinant of the customer's global satisfaction with the service. Based on role theory,...

Clustering Countries on Attitudinal Dimensions: A Review and Synthesis

Abstract: Eight empirical studies using attitudinal data to cluster countries are reviewed. The major dimensions accounting for similarities among countries are discussed, and a final synthesis of clusters is presented.

Selecting Software Test Data Using Data Flow Information

Abstract: This paper defines a family of program test data selection criteria derived from data flow analysis techniques similar to those used in compiler optimization It is argued that currently used path selection criteria, which examine only the control flow of a program, are inadequate quate Our procedure associates with each point in a program at which a variable is defined, those points at which the value is used Several test data selection criteria, differing in the type and number of these associations, are defined and compared

Elaborated Reichardt detectors

Abstract: The elaborated Reichardt detector (ERD) proposed by van Santen and Sperling [ J. Opt. Soc. Am. A1, 451 ( 1984)], based on Reichardt’s motion detector [ Z. Naturforsch. Teil B12, 447 ( 1957)], is an opponent system of two mirror-image subunits. Each subunit receives inputs from two spatiotemporal filters (receptive fields), multiplies the filter outputs, and temporally integrates the product. Subunit outputs are algebraically subtracted to yield ERD output. ERD’s can correctly indicate direction of motion of drifting sine waves of any spatial and temporal frequency. Here we prove that with a careful choice of either temporal or spatial filters, the subunits can themselves become quite similar or equivalent to the whole ERD; with suitably chosen filters, the ERD is equivalent to an elaborated version of a motion detector proposed by Watson and Ahumada [NASA Tech. Memo. 84352 (1983)]; and for every choice of filters, the ERD is fully equivalent to the detector proposed by Adelson and Bergen [ J. Opt. Soc. Am. A2, 284– 299 ( 1985)]. Some equivalences between the motion detection (in x, t) by ERD’s and spatial pattern detection (in x, y) are demonstrated. The responses of the ERD and its variants to drifting sinusoidal gratings, to other sinusoidally modulated stimuli (on–off gratings, counterphase flicker), and to combinations of sinusoids are derived and compared with data. ERD responses to two-frame motion displays are derived, and several new experimental predictions are tested experimentally. It is demonstrated that a system containing ERD’s of various sizes can solve the correspondence problem in two-frame motion of random-bar stimuli and shows the predicted phase dependencies when confronted with displays composed of triple sinusoids combined either in amplitude modulation phase or in quasi-frequency modulation phase. Finally, it is shown that, while the ERD may in some instances give larger responses to nonrigid than to rigid displacements, the subunits (and hence the ERD) are especially well behaved with continuous movement of rigid or smoothly deforming objects.

Assessing the Impact of Country of Origin on Product Evaluations: A New Methodological Perspective:

Abstract: A new methodological approach for examining the impact of country of origin on product evaluations is proposed. It takes the form of a multiattribute attitudinal model analyzed by means of a system...

Early detection of malignant melanoma: The role of physician examination and self‐examination of the skin

Abstract: The combination of routine physician examination of the skin coupled with self-examination provides a realistic opportunity for the identification of early malignant melanomas. Removal of such thin lesions can significantly reduce the mortality rate from this potentially serious form of cutaneous cancer.

Contingency Perspectives of Organizational Strategy: A Critical Review of the Empirical Research

Abstract: A two-level scheme for reviewing contingency theory research on organizational strategy is proposed. This scheme employs a systems model for delineating the domain of contingency perspectives on strategy research at the first level and incorporates relevant analytical dimensions at the second level. Patterns observed reinforce criticisms of contingency theory research in other macro-organizational areas. Recommendations pertaining to both theoretical and methodological issues are offered to strategy researchers conducting contingency theory-based empirical investigations.

Uniform decay estimates and the lorentz invariance of the classical wave equation

Abstract: On etudie le comportement asymptotique des solutions de □u=0 ou □=∂ t 2 −∂ 1 2 ...−∂ n 2 pour des conditions initiales u=0, u t =g(x) en t=0, avec g reguliere a support compact dans R n

Law, custom, and social order : the colonial experience in Malawi and Zambia

Abstract: This book explores the historical formation during the colonial period of that part of African law known as customary law. In treating the emergence of the customary law as part of the history of the social and economic transformation of African societies under colonial rule, it also provides an interpretation of the ways in which people tried to control the disrupting effects of the changes which they experienced. Martin Chanock shows how African ideas, aspirations and activities regarding law were shaped by interaction with the legal ideas of the British colonisers, their understandings of African societies, and the judicial institutions of the colonial state. These thematic considerations are illustrated by studies of how the customary law developed alongside criminal law in colonial society in Malawi and Zambia as part of the moral weaponry of a changing social order, and more specifically by describing the role of the customary law of the family in conflicts between men and women in the new colonial political economy.

The effects of psychologically based intervention programs on worker productivity: a meta-analysis

Abstract: A meta-analysis of the effects on worker productivity of 11 types of psychologically based organizational interventions showed that such programs, on average, raised worker productivity by nearly one-half standard deviation. The strength of effects was found to vary by type of intervention, criterion of productivity, contextual factors in organizations, and features of research design. Also discussed in the paper are comparisons of conclusions reached through meta-analysis versus traditional methods of literature review.

The mirror effect in recognition memory.

Abstract: The mirror effect in recognition memory refers to the fact that, with several different classes of stimuli, performance on new items from each class mirrors (is correlated with) performance on the corresponding classes of old items. Classes of stimuli that are accurately recognized as old when old are also accurately recognized as new when new; those that are poorly recognized as old when old are also poorly recognized as new when new. The statement above is shown not to be a tautology. A survey demonstrates that the effect holds for several types of variables (ways to classify stimuli)—word frequency, concreteness, meaningfulness, and others. The survey includes a total of 80 findings. The theoretical implications of the effect are considered.

Does Attitude toward the Ad Affect Brand Attitude under a Brand Evaluation Set

Abstract: The results of an experiment examining the use of attitude toward the ad and brand-related beliefs in brand attitude formation under two different processing “sets”—brand evaluation and nonbrand ev...

Spaces for the assessment of knowledge

Abstract: The information regarding a particular field of knowledge is conceptualized as a large, specified set of questions (or problems). The knowledge state of an individual with respect to that domain is formalized as the subset of all the questions that this individual is capable of solving. A particularly appealing postulate on the family of all possible knowledge states is that it is closed under arbitrary unions. A family of sets satisfying this condition is called a knowledge space. Generalizing a theorem of Birkhoff on partial orders, we show that knowledge spaces are in a one-to-one correspondence with AND/OR graphs of a particular kind. Two types of economical representations of knowledge spaces are analysed: bases, and Hasse systems, a concept generalizing that of a Hasse diagram of a partial order. The structures analysed here provide the foundation for later work on algorithmic procedures for the assessment of knowledge.

The Cholinergic Hypothesis: A Historical Overview, Current Perspective, and Future Directions

Abstract: When one considers that Alzheimer’s disease was initially characterized in the first decade of this century,’ it seems remarkable that the disease remains such a mystery. The relative etiologic roles played by various genetic, toxic, viral, and immunologic influences remain ill-defined, and the origin and direct functional implications of its most characteristic neuropathological markers, neurofibrillary tangles and amyloid plaques, likewise are unknown. Although it has been shown that inadequate blood supply to the brain does not provide a tenable explanation for the primary symptoms of Alzheimer’s disease: the final neurological pathways that are responsible remain obscure. One possible exception to this is the recent accumulation of evidence suggesting that a breakdown of central cholinergic transmission plays an important role in the earliest and primary symptoms of the disease, manifested as a severe and progressive cognitive disturbance highlighted by an inability to remember recent With normal aging, a similar, though less severe, memory loss has been documented6*’ (sometimes referred to as benign senescent forgetfulness*) with similar evidence for a parallel role of cholinergic dys f~nc t ion .~*~*~*’~ The logic and empirical support for this line of thinking have collectively become known as the “cholinergic hypothesis of geriatric memory dysf~nction.”~-~ Stated in its most simple and direct terms, the cholinergic hypothesis asserts that significant, functional disturbances in cholinergic activity occur in the brains of aged and especially demented patients, these disturbances play an important role in the memory loss and related cognitive problems associated with old age and dementia, and proper enhancement or restoration of cholinergic function may significantly reduce the severity of the cognitive loss. One should note that the cholinergic hypothesis states nothing about etiological factors responsible for aging or dementia. Rather, it attempts to explain only the most direct, cause-effect relationship associated with the primary symptoms (i.e., memory loss). Likewise, the hypothesis does not address the additional roles that cholinergic dysfunction may play in other neurobehavioral disturbances of aging or dementia. Finally, no exclusive or solitary involvement of the cholinergic system in age-related

Distribution of decay-accelerating factor in the peripheral blood of normal individuals and patients with paroxysmal nocturnal hemoglobinuria.

Abstract: Decay-accelerating factor (DAF) is a 70,000 Mr protein that has been isolated from the membrane of red cells. The function of DAF is to inhibit the assembly of amplifying enzymes of the complement cascade on the cell surface, thereby protecting them from damage by autologous complement. We raised monoclonal antibodies to DAF and used them to study its distribution in cells from the peripheral blood of normal individuals and of patients with paroxysmal nocturnal hemoglobinuria (PNH), a disease characterized by the unusual susceptibility of red cells to the hemolytic activity of complement. The results of immunoradiometric assays and of fluorescence-activated cell sorter analysis showed that DAF was present not only on red cells but was widely distributed on the surface membrane of platelets, neutrophils, monocytes, and B and T lymphocytes. By Western blotting, we observed small but consistent differences in the Mr of DAF from the membranes of various cell types. Quantitative studies showed that phagocytes and B lymphocytes, which presumably enter more frequently in contact with immune complexes and other potential activators of complement, had the highest DAF levels. As previously reported by others, the red cells from PNH patients were DAF deficient. When the patients' red cells were incubated in acidified serum (Ham test), only the DAF-deficient cells were lysed. In addition, we detected defects in DAF expression on platelets and all types of leukocytes. The observed patterns of DAF deficiency in these patients were consistent with the concept that the PNH cells were of monoclonal origin. In one patient, abnormal and normal cells were found only in the erythroid, myeloid, and megakaryocytic lineages. In two other patients, the lymphocytes were also DAF deficient, suggesting that a mutation occurred in a totipotent stem cell. It appears, therefore, that the lesion leading to PNH can occur at various stages in the differentiation of hematopoietic cells.

Rat medulla oblongata. II. Dopaminergic, noradrenergic (A1 and A2) and adrenergic neurons, nerve fibers, and presumptive terminal processes

Abstract: The aim of this study was to determine the anatomical relationships between catecholaminergic neurons and cytoarchitectonically defined nuclei in the caudal medulla oblongata. Previous studies have demonstrated the existence of noradrenergic cell bodies (designated as the A1 and A2 cell groups) in the caudal medulla oblongata of the rat (Dahlstrom and Fuxe, '64), including the nTS. There is no information currently available with regard to details of the distribution of these noradrenergic neurons in the functionally distinct subnuclei of the medulla oblongata. In this study the location of catecholamine-synthesizing enzymes was examined in the serial sections of the caudal medulla oblongata of the rat: tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), and phenylethanolamine N-methyl transferase (PNMT). The immunoperoxidase method of Sternberger ('79) was used to demonstrate the location of immunoreactive neurons, nerve fibers, and presumptive terminal processes. This was followed by Nissl staining of the same sections to localize accurately the immunoreactivity. Noradrenergic neurons (TH- and DBH-positive and PNMT-negative) were localized in a number of subnuclei of the nucleus of the tractus solitarius (nTS), the area postrema (ap), and in the dorsal motor nucleus of the vagus (dmnX). The distribution of these noradrenergic cells was different at different rostrocaudal levels. In addition, adrenergic neurons (TH-, DBH-, and PMNT-positive) were identified dorsal to the tractus solitarius (TS), in the dorsal strip region (ds), the periventricular region (PVR), the dorsal parasolitarius region (dPSR), and the dmnX (rostral to obex). In addition, dopaminergic neurons (TH-positive and DBH- and PNMT-negative) were found in the ap and dmnX. The A1 cell group in the ventrolateral medulla consisted almost exclusively of noradrenergic neurons (TH- and DBH-positive and PNMT-negative). These results indicate that in the rat the A2 cell group is a mixed population of catecholaminergic neurons that are localized in well-defined regions of the dorsal medulla oblongata. The distribution of these neurons is very specific both in terms of rostrocaudal levels and cytoarchitectonic subdivisions of regions of the medulla known to be involved in central autonomic control. This supports the hypothesis that monoaminergic neurons in the dorsal medulla play important roles in the central regulation of visceral function.

Rationale for Development of a Synthetic Vaccine Against Plasmodium falciparum Malaria

Abstract: Protective immunity against malaria can be obtained by vaccination with irradiated sporozoites. The protective antigens known as circumsporozoite (CS) proteins, are polypeptides that cover the surface membrane of the parasite. The CS proteins contain species-specific immunodominant epitopes formed by tandem repeated sequences of amino acids. Here it is shown that the dominant epitope of Plasmodium falciparum is contained in the synthetic dodecapeptide Asn-Ala-Asn-Pro-Asn-Ala-Asn-Pro-Asn-Ala-Pro or (NANP)3. Monoclonal antibodies and most or all polyclonal human antibodies to the sporozoites react with (NANP)3, and polyclonal antibodies raised against the synthetic peptide (NANP)3 react with the surface of the parasite and neutralize its infectivity. Since (NANP)3 repeats are present in CS proteins of P. falciparum from many parts of the world, this epitope is a logical target for vaccine development.

Membrane complement receptors specific for bound fragments of C3.

Abstract: Publisher Summary Even though it has been long recognized that the major function of complement receptors was clearance of bacteria by way of opsonization, there are many unknown features about the functions of phagocyte complement receptors. The characterization of the function of complement receptors represents one of the final frontiers of complement research that has detailed the functions of the plasma complement components. Both afferent and efferent limbs of the inflammatory process are dependent upon this coordinating function of complement. The organization of host cell responses by complement is achieved through the interaction of cell membrane receptors with activation products of serum complement proteins. Although a number of different complement components are involved in this complex process, C3l plays a pivotal role. During complement activation, C3-derived fragments are both liberated into the fluid phase and covalently bound to the substrate. The fluid-phase C3 fragments function to induce leukocytosis , increase vascular permeability, and suppress antibody synthesis, whereas the bound C3 fragments participate in assembly of convertase enzymes that amplify C3 activation and further progression of the complement cascade. This chapter focuses on the membrane receptors for bound fragments of C3. The chapter reviews mechanisms for generation and degradation of C3-receptor ligands via the classical and alternative pathways and discusses the abnormalities of expression and/or function that have both clinical relevance and contribute to an understanding of the function of complement receptors in vivo .

The impact of role variables on IS personnel work attitudes and intentions

Abstract: This study examines the antecedents of job satisfaction, commitment, and turnover intentions for 229 information systems (IS) personnel employed within several industries The antecedents studied include boundary spanning, role ambiguity, and role conflict A model of these variables was built and tested using path analysis Role ambiguity was found to be the most dysfunctional variable for IS personnel, accounting for 103%, 202% and 222% of the variance in turnover intentions, commitment, and job satisfaction This information is used to make recommendations to IS management Finally, recommendations and directions are suggested regarding future research

The characteristics of takeover targets and other measures

Abstract: This study attempts to assess differences in the financial characteristics of target and non-target firms using logit analysis and a case-control methodology in which control groups are matched by size or industry. The results indicate that unregulated non-financial target firms are characterized by low q ratios (market/replacement values) and to a lesser extent high current financial liquidity. Measures of financial leverage were not found to be significant.

Anatomical connections of the nucleus prepositus of the cat.

Abstract: The afferent and efferent connections of the nucleus prepositus hypoglossi with brainstem nuclei were studied using anterograde and retrograde axonal transport techniques, and by intracellular recordings and injections of horseradish peroxidase into prepositus hypoglossi neurons. The results of experiments in which horseradish peroxidase was injected into the prepositus hypoglossi suggest that the major inputs to the prepositus hypoglossi arise from the ipsi- and contralateral perihypoglossal nuclei (particularly the prepositus hypoglossi and intercalatus), vestibular nuclei (particularly the medial, inferior, and ventrolateral nuclei), the paramedian medullary and pontine reticular formation, and from the cerebellar cortex (flocculus, paraflocculus, and crus I; the nodulus was not available for study). Regions containing fewer labeled cells included the interstitial n. of Cajal, the rostral interstitial n. of the medial longitudinal fasciculus, the n. of the posterior commissure, the superior colliculus, the n. of the optic tract, the extraocular motor nuclei, the spinal trigeminal n., and the central cervical n. The efferent connections of the prepositus hypoglossi were studied by injecting 3H-leucine into the prepositus hypoglossi, and by following the axons of intracellularly injected prepositus hypoglossi neurons. The results suggest that in addition to the cerebellar cortex, the most important extrinsic targets of prepositus hypoglossi efferents are the vestibular nuclei (particularly the medial, inferior, and ventrolateral nuclei, and the area X), the inferior olive (contralateral dorsal cap of Kooy and ipsilateral subnucleus b of the medial accessory olive), the paramedian medullary and pontine reticular formation, the reticular formation surrounding the parabigeminal n., the contralateral superior colliculus and pretectum, the extraocular motor nuclei (particularly the contralateral abducens nucleus and the ipsilateral medial rectus subdivision of the oculomotor nucleus), the ventral lateral geniculate n., and the central lateral thalamic nucleus. Other areas which were lightly labeled in the autoradiographic experiments were the contralateral spinal trigeminal n., the n. raphe pontis, the Edinger Westphal n., the zona incerta, and the paracentral thalamic n. Many of the efferent connections of the prepositus hypoglossi appear to arise from principal prepositus hypoglossi neurons whose axons collateralize extensively in the brainstem. On the other hand, small prepositus hypoglossi neurons project to the inferior olive, and multidendritic neurons project to the cerebellar flocculus, apparently without collateralizing in the brainstem.(ABSTRACT TRUNCATED AT 400 WORDS)