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Showing papers by "Rutgers University published in 1991"


Journal ArticleDOI
TL;DR: A meta-analysis of the relationships between organizational innovation and 13 potential determinants resulted in statistically significant associations for specialization, functional differencing, and functional differences as mentioned in this paper. But, the authors did not consider the role of organizational innovation in organizational innovation.
Abstract: A meta-analysis of the relationships between organizational innovation and 13 of its potential determinants resulted in statistically significant associations for specialization, functional differe...

6,743 citations


Journal ArticleDOI
TL;DR: A model of the information search process is presented derived from a series of five studies investigating common experiences of users in information seeking situations, suggesting a gap between the users’ natural process of information use and the information system and intermediaries’ traditional patterns of information provision.
Abstract: The article discusses the users’ perspective of information seeking. A model of the information search process is presented derived from a series of five studies investigating common experiences of users in information seeking situations. The cognitive and affective aspects of the process of information seeking suggest a gap between the users’ natural process of information use and the information system and intermediaries’ traditional patterns of information provision.

2,062 citations


Journal ArticleDOI
TL;DR: The authors showed that the physical attractiveness stereotype established by studies of person perception is not as strong or general as suggested by the often-used summary phrase what is beautiful is good, and that the average magnitude of this beauty-is-good effect was moderate, and the strength of the effect varied considerably from study to study Consistent with their implicit personality theory framework, a substantial portion of this variation was explained by the specific content of the inferences that subjects were asked to make.
Abstract: This review demonstrates that the physical attractiveness stereotype established by studies of person perception is not as strong or general as suggested by the often-used summary phrase what is beautiful is good. Although subjects in these studies ascribed more favorable personality traits and more successful life outcomes to attractive than unattractive targets, the average magnitude of this beauty-is-good effect was moderate, and the strength of the effect varied considerably from study to study Consistent with our implicit personality theory framework, a substantial portion of this variation was explained by the specific content of the inferences that subjects were asked to make: The differences in subjects* perception of attractive and unattractive targets were largest for indexes of social competence; intermediate for potency, adjustment, and intellectual competence; and near zero for integrity and concern for others. The strength of the physical attractiveness stereotype also varied as a function of other attributes of the studies, including the presence of individuating information.

1,688 citations


Journal ArticleDOI
TL;DR: In this paper, the authors examined the impact of a realistic merger preview, a program of realistic communications, on employees of an organization that had just announced a merger, and found that the preview reduced dysfunctional outcomes of the merger.
Abstract: This study examined the impact of a realistic merger preview, a program of realistic communications, on employees of an organization that had just announced a merger. Employees in one plant received the preview and those in another received limited information. Results based on four collections of data indicated that the preview reduced dysfunctional outcomes of the merger. Those effects continued over the duration of the study and, in some cases, measured attributes returned to levels comparable to their levels before the merger was announced. We discuss implications for organizations contemplating mergers or acquisitions and for researchers interested in such activities.

1,284 citations


Journal ArticleDOI
TL;DR: In this article, the authors explore how organizations convert infrequent events into interpretations of history, and how they balance the need to achieve agreement on interpretations with the need of interpreting history correctly.
Abstract: Organizations learn from experience. Sometimes, however, history is not generous with experience. We explore how organizations convert infrequent events into interpretations of history, and how they balance the need to achieve agreement on interpretations with the need to interpret history correctly. We ask what methods are used, what problems are involved, and what improvements might be made. Although the methods we observe are not guaranteed to lead to consistent agreement on interpretations, valid knowledge, improved organizational performance, or organizational survival, they provide possible insights into the possibilities for and problems of learning from fragments of history.

1,124 citations


Journal ArticleDOI
TL;DR: A variety of bone graft and bone graft substitute materials are discussed, among the osteoconductive materials outlined are the hydroxyapatite and tricalcium phosphate ceramics and some reportedly osteoactive polymers.
Abstract: The morbidity associated with autogenous bone graft harvest and the recent concern regarding the transmission of live virus through use of allografts, have been the impetus for research into a variety of materials that could take the place of these standard materials for bone grafting. The positive results reported with various ceramics and/or bone derivatives suggest the possibility of a material with osteoconductive and/or osteoinductive properties for use with or in place of bone graft. This review discusses a variety of bone graft and bone graft substitute materials. Among the osteoconductive materials outlined are the hydroxyapatite and tricalcium phosphate ceramics as well as some reportedly osteoactive polymers. While osteoconduction is a favorable quality, much interest has focussed on the use of osteoinductive or osteogenic materials such as demineralized bone matrix or bone derivatives,that is, BMP, osteogenin, etc. It is increasingly apparent that these materials require a carrier vehicle for optimal expression of osteoactivity. Therefore, the review finishes with a comparison of the various materials suggested for use as carriers.

1,007 citations


Journal ArticleDOI
TL;DR: Self-evaluations of health status have been shown to predict mortality, above and beyond the contribution to prediction made by indices based on the presence of health problems, physical disability, and biological or life-style risk factors.
Abstract: Self-evaluations of health status have been shown to predict mortality, above and beyond the contribution to prediction made by indices based on the presence of health problems, physical disability, and biological or life-style risk factors. Several possible reasons for this association are discussed: (a) methodological shortcomings of previous studies render the association spurious; (b) other psychosocial influences on mortality are involved and explain the association; and (c) self-evaluations of health status have a direct and independent effect of their own. Four-year follow-up mortality data from the Yale Health and Aging Project (N = 2812) are used to explore these possibilities. The analysis controls for the contribution of numerous indicators of health problems, disability and risk factors, and also makes adjustments of standard errors for the complex sample design. The findings favor the third possibility, an independent effect, to the extent that the particular set of psychosocial factors examined did not explain the basic association, and to the extent that the control variables were an adequately comprehensive set.

982 citations


Journal ArticleDOI
S. Chan Choi1
TL;DR: In this article, the authors studied three noncooperative games of different power structures between the two manufacturers and the retailer, i.e., two Stackelberg and one Nash games, and showed that an exclusive dealer channel provides higher profits to all than a common retailer channel given a power structure.
Abstract: In recent studies of channel competition, it has been found that channel intermediaries reduce the intensity of direct competition between manufacturers. The underlying channel structure in most studies consists of two manufacturers and two retailers each of whom sells only one manufacturer's product exclusively. This paper adds to this growing literature of channel competition by analyzing a channel structure with two competing manufacturers and one intermediary a common retailer that sells both manufacturers' products. Unlike some exclusive dealers or retail outlets of a manufacturer, however, a common retailer is often a powerful player in the market. This paper studies three noncooperative games of different power structures between the two manufacturers and the retailer, i.e., two Stackelberg and one Nash games. It is shown that some of the results depend critically on the form of the demand function. With a linear demand function, a manufacturer is better off by maintaining exclusive dealers while a retailer has an incentive to deal with several producers. All channel members as well as consumers are better off when no one dominates the market. The common retailer benefits more than the manufacturers do from a symmetric decrease in the manufacturing cost. As products are less differentiated, all channel members' prices and profits increase: a counterintuitive result. When the demand function is nonlinear, however, an exclusive dealer channel provides higher profits to all than a common retailer channel given a power structure. As products are more differentiated, a manufacturer's profit decreases when a common retailer is used, but increases when an exclusive dealer is used. These results underscore the importance of choosing a correct demand function for a channel decision.

977 citations


Book
01 Jan 1991
TL;DR: In this article, the authors discuss the importance of unbiased error rate estimation and find the right complexity fit to estimate the true performance of a learning system and compare it to the expected patterns of classifier behavior.
Abstract: Preface 1 Overview of Learning Systems 1.1 What is a Learning System? 1.2 Motivation for Building Learning Systems 1.3 Types of Practical Empirical Learning Systems 1.3.1 Common Theme: The Classification Model 1.3.2 Let the Data Speak 1.4 What's New in Learning Methods 1.4.1 The Impact of New Technology 1.5 Outline of the Book 1.6 Bibliographical and Historical Remarks 2 How to Estimate the True Performance of a Learning System 2.1 The Importance of Unbiased Error Rate Estimation 2.2. What is an Error? 2.2.1 Costs and Risks 2.3 Apparent Error Rate Estimates 2.4 Too Good to Be True: Overspecialization 2.5 True Error Rate Estimation 2.5.1 The Idealized Model for Unlimited Samples 2.5.2 Train-and Test Error Rate Estimation 2.5.3 Resampling Techniques 2.5.4 Finding the Right Complexity Fit 2.6 Getting the Most Out of the Data 2.7 Classifier Complexity and Feature Dimensionality 2.7.1 Expected Patterns of Classifier Behavior 2.8 What Can Go Wrong? 2.8.1 Poor Features, Data Errors, and Mislabeled Classes 2.8.2 Unrepresentative Samples 2.9 How Close to the Truth? 2.10 Common Mistakes in Performance Analysis 2.11 Bibliographical and Historical Remarks 3 Statistical Pattern Recognition 3.1 Introduction and Overview 3.2 A Few Sample Applications 3.3 Bayesian Classifiers 3.3.1 Direct Application of the Bayes Rule 3.4 Linear Discriminants 3.4.1 The Normality Assumption and Discriminant Functions 3.4.2 Logistic Regression 3.5 Nearest Neighbor Methods 3.6 Feature Selection 3.7 Error Rate Analysis 3.8 Bibliographical and Historical Remarks 4 Neural Nets 4.1 Introduction and Overview 4.2 Perceptrons 4.2.1 Least Mean Square Learning Systems 4.2.2 How Good Is a Linear Separation Network? 4.3 Multilayer Neural Networks 4.3.1 Back-Propagation 4.3.2 The Practical Application of Back-Propagation 4.4 Error Rate and Complexity Fit Estimation 4.5 Improving on Standard Back-Propagation 4.6 Bibliographical and Historical Remarks 5 Machine Learning: Easily Understood Decision Rules 5.1 Introduction and Overview 5.2 Decision Trees 5.2.1 Finding the Perfect Tree 5.2.2 The Incredible Shrinking Tree 5.2.3 Limitations of Tree Induction Methods 5.3 Rule Induction 5.3.1 Predictive Value Maximization 5.4 Bibliographical and Historical Remarks 6 Which Technique is Best? 6.1 What's Important in Choosing a Classifier? 6.1.1 Prediction Accuracy 6.1.2 Speed of Learning and Classification 6.1.3 Explanation and Insight 6.2 So, How Do I Choose a Learning System? 6.3 Variations on the Standard Problem 6.3.1 Missing Data 6.3.2 Incremental Learning 6.4 Future Prospects for Improved Learning Methods 6.5 Bibliographical and Historical Remarks 7 Expert Systems 7.1 Introduction and Overview 7.1.1 Why Build Expert Systems? New vs. Old Knowledge 7.2 Estimating Error Rates for Expert Systems 7.3 Complexity of Knowledge Bases 7.3.1 How Many Rules Are Too Many? 7.4 Knowledge Base Example 7.5 Empirical Analysis of Knowledge Bases 7.6 Future: Combined Learning and Expert Systems 7.7 Bibliographical and Historical Remarks References Author Index Subject Index

813 citations


Journal ArticleDOI
TL;DR: The physico-mechanical properties of degradable polymers used for medical applications have been characterized and flexural storage modulus as a function of temperature was determined by dynamic mechanical analysis.

736 citations


Journal ArticleDOI
TL;DR: This article found that entrepreneurs spend significantly more time searching for information in their off hours and through nonverbal scanning than executives and paid special attention to risk cues about new opportunities, while executives tended to focus on the economics of the opportunity.

Journal ArticleDOI
TL;DR: It is suggested that simple manipulations of the configuration of extracellular elements can dramatically alter the behavior of cultured hepatocytes.
Abstract: In an effort to reconstruct the cellular polarity normally found in the liver, adult rat hepatocytes were sandwiched between two layers of hydrated rat tail tendon collagen matrix. Functionally, sandwiched hepatocytes maintained the secretion of albumin, transferrin, fibrinogen, bile acids, and urea for at least 6 weeks, whereas cells cultured on a single layer of collagen gel ceased such secretion in 1-2 weeks. After 1 week of culture on a single layer of collagen gel, hepatocytes could still recover these lost functions when a second layer of collagen gel was applied. The exact nature of the substrate for constructing the sandwich system appeared to be unimportant as long as it allowed cellular attachment. Hepatocytes cultured in the sandwich system appeared to maintain a distribution of actin filaments similar to the in vivo state, whereas cells cultured on a single layer of collagen gel showed abnormal formation of stress fibers. These studies suggest that simple manipulations of the configuration of extracellular elements can dramatically alter the behavior of cultured hepatocytes.

Journal ArticleDOI
TL;DR: Sperm nuclei contain a unique structure termed the sperm nuclear annulus to which the entire complement of DNA appears to be anchored when the nuclear matrix is disrupted during decondensation, and the structural organization of sperm DNA is likely to be just as vital to the proper functioning of the spermatozoa.
Abstract: Mammalian sperm DNA is the most tightly compacted eukaryotic DNA, being at least sixfold more highly condensed than the DNA in mitotic chromosomes. To achieve this high degree of packaging, sperm DNA interacts with protamines to form linear, side-by-side arrays of chromatin. This differs markedly from the bulkier DNA packaging of somatic cell nuclei and mitotic chromosomes, in which the DNA is coiled around histone octamers to form nucleosomes. The overall organization of mammalian sperm DNA, however, resembles that of somatic cells in that both the linear arrays of sperm chromatin and the 30-nm solenoid filaments of somatic cell chromatin are organized into loop domains attached at their bases to a nuclear matrix. In addition to the sperm nuclear matrix, sperm nuclei contain a unique structure termed the sperm nuclear annulus to which the entire complement of DNA appears to be anchored when the nuclear matrix is disrupted during decondensation. In somatic cells, proper function of DNA is dependent upon the structural organization of the DNA by the nuclear matrix, and the structural organization of sperm DNA is likely to be just as vital to the proper functioning of the spermatozoa.

Journal ArticleDOI
TL;DR: In this article, uniform estimates and blow-up behavior for solutions of −δ(u) = v(x)eu in two dimensions are presented, with a focus on partial differential equations.
Abstract: (1991). Uniform estimates and blow–up behavior for solutions of −δ(u)=v(x)eu in two dimensions. Communications in Partial Differential Equations: Vol. 16, No. 8-9, pp. 1223-1253.

Journal ArticleDOI
TL;DR: In this paper, dehydrated sugar solutions were used as models of thermal behavior of amorphous foods, and of the effect of temperature, moisture content and time on physical state of such foods.
Abstract: Dehydrated sugar solutions were used as models of thermal behavior of amorphous foods, and of the effect of temperature, moisture content and time on physical state of such foods. The transition temperatures determined were glass transition (Tg), crystallization (Tcr) and melting (Tm) which all decreased with increasing moisture. Tg of a sucrose/ fructose model had a slightly lower value than the empirical “sticky point,” at all moisture contents studied. Crystallization of sucrose was delayed by addition of fructose or starch. Crystallization above Tg was time-dependent, and the relaxation time of this process followed the WLF equation.

Journal Article
TL;DR: The inhibitory effects of curcumin, chlorogenic acid, caffeic acid, and ferulic acid on TPA-induced tumor promotion in mouse epidermis parallel their inhibitory effect on T PA-induced epidermal inflammation and epider mal lipoxygenase and cyclo oxygengenase activities.
Abstract: Topical application of curcumin, the yellow pigment in turmeric and curry, strongly inhibited 12- O -tetradecanoylphorbol-13-acetate (TPA)-induced ornithine decarboxylase activity, DNA synthesis, and tumor promotion in mouse skin (Huang et al. , Cancer Res., 48: 5941–5946, 1988). Chlorogenic acid, caffeic acid, and ferulic acid (structurally related dietary compounds) were considerably less active. In the present study, topical application of curcumin markedly inhibited TPA- and arachidonic acid-induced epidermal inflammation (ear edema) in mice, but chlorogenic acid, caffeic acid, and ferulic acid were only weakly active or inactive. The in vitro addition of 3, 10, 30, or 100 µm curcumin to cytosol from homogenates of mouse epidermis inhibited the metabolism of arachidonic acid to 5-hydroxyeicosatetraenoic acid (5-HETE) by 40, 60, 66, or 83%, respectively, and the metabolism of arachidonic acid to 8-HETE was inhibited by 40, 51, 77, or 85%, respectively [IC 50 (concentration needed for 50% inhibition) = 5–10 µm]. Chlorogenic acid, caffeic acid, or ferulic acid (100 µm) inhibited the metabolism of arachidonic acid to 5-HETE by 36, 10, or 16%, respectively, and these hydroxylated cinnamic acid derivatives inhibited the metabolism of arachidonic acid to 8-HETE by 37, 20, or 10%, respectively (IC 50 > 100 µm). The metabolism of arachidonic acid to prostaglandin E 2 , prostaglandin F 2α , and prostaglandin D 2 by epidermal microsomes was inhibited approximately 50% by the in vitro addition of 5–10 µm curcumin. Chlorogenic acid, caffeic acid, and ferulic acid (100 µm) were inactive. In vitro rat brain protein kinase C activity was not affected by 50–200 µm curcumin, chlorogenic acid, caffeic acid, or ferulic acid. The inhibitory effects of curcumin, chlorogenic acid, caffeic acid, and ferulic acid on TPA-induced tumor promotion in mouse epidermis parallel their inhibitory effects on TPA-induced epidermal inflammation and epidermal lipoxygenase and cyclooxygenase activities.

Journal ArticleDOI
TL;DR: Aydin et al. as mentioned in this paper found that the attitudes of specific others' actual attitudes have only a small effect on one's attitude and that differences in attitudes among occupational groups may have been due to implementation policies.
Abstract: We thank the organizational respondents for their patience and insights and Dr. Lynne Markus for her role in initiating the larger research project. We thank David Krackhardt, Bill Stevenson, Howard Nixon, Jr., Joseph Schmitz, and the anonymous reviewers, Editor John Freeman and Managing Editor Linda Pike for their comments. We also thank Steve Borgatti, Lin Freeman, and Bill Richards for providing network analysis software. The research was conducted while Dr. Aydin was a doctoral student at the University of Southern California. This study explicates and tests three network-based mechanisms whereby individuals' attitudes toward an integrated health information system may be influenced by the attitudes of proximate sources of social information. Estimates of the attitudes of generalized others are not convincingly associated with the actual attitudes of specified others. Overall, specific others' actual attitudes have only a small effect on one's attitude. Social information operates positively through communication and work-unit mechanisms (especially when weighted by importance), and negatively through the mean attitude of one's structurally equivalent position, but not through overall organizational proximity or spatial proximity. Differences in attitudes among occupational groups may have been due to implementation policies.'

Journal ArticleDOI
01 Jan 1991-Neuron
TL;DR: It is reported that a subpopulation of neurons in dissociated cell cultures of embryonic rat hippocampus expresses calbindin-D28k (Mr 28,000 calcium-binding protein) immunoreactivity and that these neurons are relatively resistant to neurotoxicity induced by either glutamate or calcium ionophore.

Journal ArticleDOI
TL;DR: In this paper, the authors focus on three dominant theoretical models: indirect victimization, community concern, and incivilities, and conclude that these models do not capture the true nature of fear of crime.
Abstract: Current work on fear of crime centers largely around three dominant theoretical models: indirect victimization, community concern, and incivilities. Previous work (Taylor and Hale 1986) confirms th...

Journal ArticleDOI
Nasser Yalpani1, Paul Silverman1, T M Wilson1, D A Kleier1, Ilya Raskin1 
TL;DR: The hypothesis that salicylic acid acts as an endogenous signal that triggers local and systemic induction of PR-1 proteins and, possibly, some components of systemic acquired resistance in NN tobacco is supported.
Abstract: Systemic induction of pathogenesis-related (PR) proteins in tobacco, which occurs during the hypersensitive response to tobacco mosaic virus (TMV), may be caused by a minimum 10-fold systemic increase in endogenous levels of salicylic acid (SA). This rise in SA parallels PR-1 protein induction and occurs in TMV-resistant Xanthi-nc tobacco carrying the N gene, but not in TMV-susceptible (nn) tobacco. By feeding SA to excised leaves of Xanthi-nc (NN) tobacco, we have shown that the observed increase in endogenous SA levels is sufficient for the systemic induction of PR-1 proteins. TMV infection became systemic and Xanthi-nc plants failed to accumulate PR-1 proteins at 32 degrees C. This loss of hypersensitive response at high temperature was associated with an inability to accumulate SA. However, spraying leaves with SA induced PR-1 proteins at both 24 and 32 degrees C. SA is most likely exported from the primary site of infection to the uninfected tissues. A computer model predicts that SA should move rapidly in phloem. When leaves of Xanthi-nc tobacco were excised 24 hr after TMV inoculation and exudates from the cut petioles were collected, the increase in endogenous SA in TMV-inoculated leaves paralleled SA levels in exudates. Exudation and leaf accumulation of SA were proportional to TMV concentration and were higher in light than in darkness. Different components of TMV were compared for their ability to induce SA accumulation and exudation: three different aggregation states of coat protein failed to induce SA, but unencapsidated viral RNA elicited SA accumulation in leaves and phloem. These results further support the hypothesis that SA acts as an endogenous signal that triggers local and systemic induction of PR-1 proteins and, possibly, some components of systemic acquired resistance in NN tobacco.

Journal ArticleDOI
01 Apr 1991-Gene
TL;DR: Four new Escherichia coli cloning vectors are described, pUC6S, p UC21, pUK21 and pOK12, which contain a polylinker or multiple cloning site (MCS) with the recognition sequences for 28 restriction enzymes allowing blue/white screening for inserts.

Book ChapterDOI
01 Jan 1991
TL;DR: Classical as mentioned in this paper is a recently developed knowledge representation system that concentrates on the definition of structured concepts, their organization into taxonomies, the creation and manipulation of individual instances of such concepts, and the key inferences of subsumption and classification.
Abstract: CLASSIC is a recently developed knowledge representation system that follows the paradigm originally set out in the KL-ONE system: It concentrates on the definition of structured concepts, their organization into taxonomies, the creation and manipulation of individual instances of such concepts, and the key inferences of subsumption and classification. Rather than simply presenting a description of CLASSIC, we complement a brief system overview with a discussion of how to live within the confines of a limited object-oriented deductive system. By analyzing the representational strengths and weaknesses of CLASSIC, we consider the circumstances under which it is most appropriate to use (or not use) it. We elaborate a knowledge engineering methodology for building KL-ONE-style knowledge bases, with emphasis on the modeling choices that arise in the process of describing a domain. We also address some of the key difficult issues encountered by new users, including primitive vs. defined concepts, and differences between roles and concepts, as well as representational “tricks-of-the-trade,” which we believe to be generally useful. Much of the discussion should be relevant to many of the current systems based on KL-ONE.

Journal ArticleDOI
TL;DR: In this paper, the authors considered the problem of global stabilization for a class of cascade systems, where the first part of the cascade is a linear controllable system and the second part is a nonlinear system receiving the inputs from the states of the first one.
Abstract: The problem of global stabilization is considered for a class of cascade systems. The first part of the cascade is a linear controllable system and the second part is a nonlinear system receiving the inputs from the states of the first part. With zero input, the equilibrium of the nonlinear part is globally asymptotically stable. In linear systems, a peaking phenomenon occurs when high-gain feedback is used to produce eigenvalues with very negative real parts. It is established that the destabilizing effects of peaking can be reduced if the nonlinearities have sufficiently slow growth. A detailed analysis of the peaking phenomenon is provided. The tradeoffs between linear peaking and nonlinear growth conditions are examined. >

Journal ArticleDOI
TL;DR: Equilibrium point analysis is used to evaluate system behavior in a packet reservation multiple access (PRMA) protocol based network and the probability of packet dropping given the number of simultaneous conversations is derived.
Abstract: Equilibrium point analysis is used to evaluate system behavior in a packet reservation multiple access (PRMA) protocol based network. The authors derive the probability of packet dropping given the number of simultaneous conversations. The authors establish conditions for system stability and efficiency. Numerical calculations based on the theory show close agreement with computer simulations. They also provide valuable guides to system design. Because PRMA is a statistical multiplexer, the channel becomes congested when too many terminals are active. For a particular example it is shown that speech activity detection permits 37 speech terminals to share a PRMA channel with 20 slots per frame, with a packet dropping probability of less than 1%. >

Journal ArticleDOI
TL;DR: This behavior successfully forecast the ability of both flavonoids to suppress tumor multiplicity and ultimately tumor development.
Abstract: Dietary quercetin (QU) and rutin (RU), phenolic flavonoids commonly found in many fruits and vegetables, were provided to CF1 female mice for 50 weeks to assess the ability of these compounds to inhibit azoxymethanol (AOM)-induced colonic neoplasia. In addition to a control group fed an AIN 76A diet, five other groups received that diet to which was added either 0.1, 0.5 or 2.0% QU and 1.0 or 4.0% RU. Acute studies revealed that, among saline controls, no alteration of any proliferative parameters of colonic epithelial cells was observed among those groups receiving any dose of QU or RU. However, among the AOM-treated mice, both 2% QU and 4% RU significantly reduced hyperproliferation and inhibited the shift of S-phase cells to the middle and upper portion of crypts. Moreover, mice fed these concentrations of QU and RU had significantly fewer AOM-induced focal areas of dysplasia (FADs) than those fed the control diet (0.2 +/- 0.4 and 0.4 +/- 0.5 versus 3.6 +/- 2.3 respectively). Tumors occurred more frequently in the distal half of the colon, regardless of treatment. Compared with controls, mice fed 2% QU had a significantly reduced tumor incidence (25.0% versus 5.9%, P = 0.03). Those fed 4% RU showed only a trend toward inhibition (25% versus 9.7%, P = 0.11). Nevertheless, both 2% QU and 4% RU suppressed tumor multiplicity, i.e. fewer tumors/animal arose in these groups than in the AOM-treated control mice (1.2 versus 2.3, P = 0.005; 1.1 versus 2.3, P = 0.003 respectively). Clearly, QU and RU exhibit significant activity in reducing AOM-induced hyperproliferation of colonic epithelial cells and FAD incidence. This behavior successfully forecast the ability of both flavonoids to suppress tumor multiplicity and ultimately tumor development.

Journal ArticleDOI
01 Oct 1991-Brain
TL;DR: Results suggest that increases in cerebrospinal fluid within the sulci of these cortical regions accompany grey matter decreases, and smaller reductions in volume are observed in subcortical grey matter nuclei.
Abstract: In the present study using magnetic resonance imaging (MRI), age changes in the morphology of the cerebral cortex, greatest in the frontal and parietal convexities, were observed during adolescence. Results suggest that increases in cerebrospinal fluid (CSF) within the sulci of these cortical regions accompany grey matter decreases. Smaller reductions in volume are also observed in subcortical grey matter nuclei. These apparent grey matter volume reductions presumably reflect processes of late brain maturation. The changes may be related to decreasing neural plasticity.

Journal ArticleDOI
Lee Jussim1
TL;DR: In this article, a reflection-construction model of relations between social perception and social reality is presented, and the model is used to model the relationship between perception and reality in social perception.
Abstract: This article presents a reflection-construction model of relations between social perception and social reality.

Journal ArticleDOI
TL;DR: In this article, the authors argue that organizational or corporate culture is strongly influenced by the characteristics of the industry in which the company operates and that companies within an industry share certain cultural elements that are required for survival.
Abstract: This article develops the argument that organizational or corporate culture is strongly influenced by the characteristics of the industry in which the company operates. Thus, companies within an industry share certain cultural elements that are required for survival. The article identifies three classes of industry variables that have the potential for creating industry-driven cultural elements: competitive environment, customer requirements, and societal expectations. The article also discusses implications of the industry influences on the potential for culture change.

Journal ArticleDOI
TL;DR: The influence of several variables on PRMA efficiency, defined as the number of conversations per channel, is examined and it is found that with 32-kb/s speech coding and 720- kb/s transmission (22.5 channels), PRMA supports up to 37 simultaneous conversations, or 1.64 conservations per channel.
Abstract: Packet-reservation multiple access (PRMA) is viewed as a merger of slotted ALOHA and time-division multiple access (TDMA). Dispersed terminals transmit packets of speech information to a central base station. When its speech activity detector indicates the beginning of a talkspurt, a terminal contends with other terminals for access to an available time slot. After the base station detects the first packet in the talkspurt, the terminal reserves future time slots for transmission of subsequent speech packets. The influence of several variables on PRMA efficiency, defined as the number of conversations per channel, is examined. The number of channels is the ratio of transmission rate to speech coding rate. It is found that with 32-kb/s speech coding and 720-kb/s transmission (22.5 channels), PRMA supports up to 37 simultaneous conversations, or 1.64 conservations per channel. The number of conversations per channel is at least 1.5 over a wide range of packet sizes (8 ms of speech per packet to 34 ms) and for all systems with 16 or more channels (transmission rate >or=512 kb/s, with 32-kb/s speech coding). Other factors studied are the sensitivity of the speech activity detector, the retransmission probability of the contention scheme, and the maximum time delay for the transmission of speech packets. >

Journal ArticleDOI
TL;DR: In this paper, the authors provide a formula for stabilizing feedback law using a bounded control, under the assumption that an appropriate control-Lyapunov function is known such a feedback, smooth away from the origin and continuous everywhere, is known via Artstein's Theorem.