Showing papers by "University of Massachusetts Amherst published in 1988"
TL;DR: This paper analyzed the relationship between perceptions of firms' corporate social responsibility and measures of their financial performance and found that a firm's prior performance, assessed by both stock-market returns and accounting-based measures, is more closely related to corporate social concern than is subsequent performance.
Abstract: Using Fortune magazine's ratings of corporate reputations, we analyzed the relationships between perceptions of firms’ corporate social responsibility and measures of their financial performance. Results show that a firm's prior performance, assessed by both stock-market returns and accounting-based measures, is more closely related to corporate social responsibility than is subsequent performance. Results also show that measures of risk are more closely associated with social responsibility than previous studies have suggested.
2,862 citations
TL;DR: Especially noteworthy among several differences in risk factor levels by demographic subgroup, were a higher body mass index among black than white women and much higher prevalence of cigarette smoking among persons with no more than a high school education than among those with more education.
1,486 citations
TL;DR: In this paper, the authors used complementary DNA libraries constructed from peripheral tissues to determine whether the messenger RNA encoding APP in these tissues is identical to that expressed in brain, and identified a second APP mRNA that encodes an additional internal domain with a sequence characteristic of a Kunitz-type serine protease inhibitor.
Abstract: Amyloid B-protein/amyloid A4 is a peptide present in the neuritic plaques, neurofibrillary tangles and cerebrovascular deposits in patients with Alzheimer's disease and Down's syndrome (trisomy 21)1–4 and may be involved in the pathogenesis of Alzheimer's disease5. Recent molecular genetic studies have indicated that amyloid protein is encoded as part of a larger protein by a gene on human chromosome 21 (refs 6–9). The amyloid protein precursor (APP) gene is expressed in brain and in several peripheral tissues, but the specific biochemical events leading to deposition of amyloid are not known. We have now screened complementary DNA libraries constructed from peripheral tissues to determine whether the messenger RNA encoding APP in these tissues is identical to that expressed in brain, and we identify a second APP mRNA that encodes an additional internal domain with a sequence characteristic of a Kunitz-type serine protease inhibitor. The alternative APP mRNA is present in both brain and peripheral tissues of normal individuals and those with Alzheimer's disease, but its pattern of expression differs from that of the previously reported APP mRNA.
1,122 citations
TL;DR: In this paper, a nonexponential empirical model was proposed to predict moisture contents after long exposure from experimental data obtained in relatively short time, i.e., well before the moisture level appeared to reach a plateau.
Abstract: Published sorption curves in the form of moisture vs time relationships of milk powder and rice, exposed to moist atmosphere or soaked In water, were fitted by a two parameter, nonexponential empirical model. The model enabled prediction of moisture contents after long exposure from experimental data obtained in relatively short time, i.e., well before the moisture level appeared to reach a plateau. The model implied that the moisture equilibrium was somewhat higher than that determined on the assumption that the sample reached a constant weight, but there was no conclusive evidence that this was really the case.
930 citations
TL;DR: In spite of the higher cell yields obtained with octanoate and nonanoate, the use of hexanoates and heptanoate yielded higher-molecular-weight polymers, which represent an entirely new class of biodegradable thermoplastics.
Abstract: Pseudomonas oleovorans was grown in homogeneous media containing n-alkanoic acids, from formate to decanoate, as the sole carbon sources. Formation of intracellular poly(β-hydroxyalkanoates) was observed only for hexanoate and the higher n-alkanoic acids. The maximum isolated polymer yields were approximately 30% of the cellular dry weight with growth on either octanoate or nonanoate. In most cases, the major repeating unit in the polymer had the same chain length as the n-alkanoic acid used for growth, but units with two carbon atoms less or more than the acid used as a carbon source were also generally present in the polyesters formed. Indeed, copolymers containing as many as six different types of β-hydroxyalkanoate units were formed. The weight average molecular weights of the poly(β-hydroxyalkanoate) copolymers produced by P. oleovorans ranged from 90,000 to 370,000. In spite of the higher cell yields obtained with octanoate and nonanoate, the use of hexanoate and heptanoate yielded higher-molecular-weight polymers. These copolyesters represent an entirely new class of biodegradable thermoplastics.
856 citations
TL;DR: It is shown that the root locations of the entire family can be completely determined by examining only the roots of the polynomials contained in the exposed edges of the polytope.
Abstract: The presence of uncertain parameters in a state space or frequency domain description of a linear, time-invariant system manifests itself as variability in the coefficients of the characteristic polynomial. If the family of all such polynomials is polytopic in coefficient space, we show that the root locations of the entire family can be completely determined by examining only the roots of the polynomials contained in the exposed edges of the polytope. These procedures are computationally tractable, and this criterion improves upon the presently available stability tests for uncertain systems, being less conservative and explicitly determining all root locations. Equally important is the fact that the results are also applicable to discrete-time systems.
794 citations
694 citations
TL;DR: In this article, the authors investigated factors controlling the concentration of dissolved hydrogen gas in anaerobic sedimentary environments and found that only microorganisms catalyze the oxidation of H 2 coupled to the reduction of nitrate, Mn(IV), Fe(III), sulfate, or carbon dioxide.
642 citations
TL;DR: This article argued that the major dichotomy is between a Laryngeal node and a place node, and that the manners of articulation in the segment itself rather than any of its subsidiary parts.
Abstract: A fundamental problem in phonological theory is the fact that processes often operate on consistent subsets of the distinctive features within a segment, like the features that characterize place of articulation. Recent research has responded to this problem by proposing a hierarchical organization of the features into functionally related classes, grouped under nodes of a tree structure. This ‘geometry’ resembles earlier theories that accomplish the same thing with multivalued features. This article reviews and expands the evidence for feature geometry. Within the segment, it is argued, the major dichotomy is between a Laryngeal node and a Place node. The manners of articulation – sonority, consonantality, nasality, and continuance – inhere in the segment itself rather than any of its subsidiary parts. Within the Place node, the division is into major articulators, each with its own subordinate features. Evidence is drawn from processes of assimilation and debuccalization and from the assimilatory and dissimilatory effects of the Obligatory Contour Principle.
620 citations
TL;DR: Readers' eye movements were recorded as they read sentences containing lexically ambiguous words or unambiguous control words in this paper, where the ambiguous words had either two equally likely interpretations (equibiased words) or one highly dominant interpretation (non-equibiases) in half the trials, while in the remaining trials the disambiguating clause followed the target word.
561 citations
TL;DR: Results from this study suggest that an adaptation takes place such that the muscle is more resistant to damage and any damage that does occur is repaired at a faster rate.
Abstract: This study examined exercise-induced muscle damage, repair, and rapid adaptation Eight college-age women performed three eccentric exercises of the forearm flexors One arm performed 70 maximal contractions (70-MAX condition), and the other arm performed 24 maximal contractions (24-MAX) followed 2 wk later by 70 maximal contractions (70-MAX2) Criterion measures of serum creatine kinase, muscle soreness and pain, isometric strength, and muscle shortening were assessed before, immediately after, and for 5 days after each exercise Significant changes in all criterion measures were found after the 70-MAX exercise with a slow recovery that was not complete by day 5 after exercise The 24-MAX condition showed only small changes in the criterion measures Changes in the criterion measures after the 70-MAX2 exercise were significantly smaller than those after the 70-MAX exercise Results from this study, with regard to the ability of the muscle to adapt to exercise-induced damage, suggest that an adaptation takes place such that the muscle is more resistant to damage and any damage that does occur is repaired at a faster rate It is also clear that a relatively small insult will produce this adaptation
TL;DR: The importance of tropospheric O(3) within the chemical climatology of the authors' environment and its effects on vegetation is re-emphasized, with the fact that plant health is the product of its interaction with the physical and chemical Climatology and pathogens and pests.
TL;DR: In this paper, Lysimetry and tracer tests are used to evaluate recharge at arid sites, particularly in siting waste disposal facilities, where reliable recharge estimates are needed.
Abstract: Arid-site recharge, while generally low, can be highly variable. Recharge under similar climate and soil conditions but with different plant cover and topography can vary from zero to more than the annual precipitation. Simple estimates of recharge based on fixed fractions of annual precipitation are misleading because they do not reflect the plant and soil factors controlling recharge. Detailed water balance models, successful for irrigated agriculture, fail to predict evapotranspiration accurately under conditions where plants suffer seasonal water stress and cover is sparse. Recharge, when estimated as a residual in water balance models, may be in error by as much as an order of magnitude. Similar errors can occur when soil water flow models are used with measured or estimated soil hydraulic conductivities and tension gradients. Lysimetry and tracer tests offer the best hope for evaluating recharge at arid sites, particularly in siting waste disposal facilities, where reliable recharge estimates are needed. Quantification of drainage using lysimetry over several years under a given set of soil, plant, and climate conditions for a specific site can provide a basis for calibrating models for recharge prediction. Tracer tests using such long-lived tracers as 36Cl or perhaps stable isotopes (180, deuterium) can provide qualitative estimates of recent recharge at a given site.
TL;DR: The prevalence and severity of the behaviors increased with global severity of dementia, but did not differ in either frequency or type when patients with three diagnoses were compared: Alzheimer's disease, multi‐infarct dementia, and mixed AD and MID (MIX).
Abstract: Patients with dementia often manifest troublesome and disruptive behaviors in addition to intellectual impairments. This study evaluated behavioral disturbances in 126 demented patients examined sequentially, using questionnaires administered to primary caregivers to quantify the types and severity of behavioral disturbances. Eighty-three percent of the patients exhibited one or more of the targeted behaviors. The most common troublesome and disruptive behaviors clustered into three categories: aggressive, ideational, and vegetative. The prevalence and severity of the behaviors increased with global severity of dementia, but did not differ in either frequency or type when patients with three diagnoses were compared: Alzheimer's disease (AD), multi-infarct dementia (MID), and mixed AD and MID (MIX). The occurrence and severity of the target behaviors correlated modestly with the severity of dementia. Impairments of mental status correlated weakly with only a single troublesome and disruptive behavior—assaultiveness.
These results suggest that troublesome and disruptive behaviors are a very frequent component of dementing disorders, are related to disease severity, and parallel (but are probably not determined by) intellectual deficit.
TL;DR: Results indicate that the type II IGF receptor contains cooperative, high-affinity binding sites for both IGF-II and Man-6-P-containing proteins.
Abstract: Amino acid sequences deduced from rat complementary DNA clones encoding the insulin-like growth factor II (IGF-II) receptor closely resemble those of the bovine cation-independent mannose-6-phosphate receptor (Man-6-P receptorCI), suggesting they are identical structures. It is also shown that IGF-II receptors are adsorbed by immobilized pentamannosyl-6-phosphate and are specifically eluted with Man-6-P. Furthermore, Man-6-P specifically increases by about two times the apparent affinity of the purified rat placental receptor for 125I-labeled IGF-II. These results indicate that the type II IGF receptor contains cooperative, high-affinity binding sites for both IGF-II and Man-6-P-containing proteins.
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01 Jun 1988TL;DR: In this article, the authors describe three mechanisms that improve network coherence: an organizational structure that provides a long-term framework for network coordination to guide each node's local control decisions; a planner at each node that develops sequences of problem-solving activities based on the current situation; and meta-level communication about the current state of local problem solving that enables nodes to dynamically refine the organization.
Abstract: When two or more computing agents work on interacting tasks, their activities should be coordinated so that they cooperate coherently. Coherence is particularly problematic in domains where each agent has only a limited view of the overall task, where communication between agents is limited, and where there is no ``controller'' to coordinate the agents. Our approach to coherent cooperation in such domains is developed in the context of a distributed problem-solving network where agents cooperate to solve a single problem. The approach stresses the importance of sophisticated local control by which each problem-solving node integrates knowledge of the problem domain with (meta-level) knowledge about network coordination. This allows nodes to make rapid, intelligent local decisions based on changing problem characteristics with only a limited amount of intercommunication to coordinate these decisions. We describe three mechanisms that improve network coherence: 1) an organizational structure that provides a long-term framework for network coordination to guide each node's local control decisions; 2) a planner at each node that develops sequences of problem-solving activities based on the current situation; and 3) meta-level communication about the current state of local problem solving that enables nodes to dynamically refine the organization. We present a variety of problem-solving situations to show the benefits and limitations of these mechanisms, and we provide simulation results showing the mechanisms to be particularly cost effective in more complex problem-solving situations. We also discuss how these mechanisms might be of more general use in other distributed computing applications.
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01 Jun 1988TL;DR: In this article, a new approach for structuring distributed processing systems, called functionally accurate, cooperative (FA/C), is proposed, which is especially suited to applications in which the data necessary to achieve a solution cannot be partitioned in such a way that a node can complete a task without seeing the intermediate state of task processing at other nodes.
Abstract: A new approach for structuring distributed processing systems, called functionally accurate, cooperative (FA/C), is proposed. The approach differs from conventional ones in its emphasis on handling distribution-caused uncertainty and errors as an integral part of the network problem-solving process. In this approach nodes cooperatively problem-solve by exchanging partial tentative results (at various levels of abstraction) within the context of common goals. The approach is especially suited to applications in which the data necessary to achieve a solution cannot be partitioned in such a way that a node can complete a task without seeing the intermediate state of task processing at other nodes. Much of the inspiration for the FA/C approach comes from the mechanisms used in knowledge-based artificial intelligence (Al) systems for resolving uncertainty caused by noisy input data and the use of approximate knowledge. The appropriateness of the FA/C approach is explored in three application domains: distributed interpretation, distributed network traffic-light control, and distributed planning. Additionally, the relationship between the approach and the structure of management organizations is developed. Finally, a number of current research directions necessary to more fully develop the FA/C approach are outlined. These research directions include distributed search, the integration of implicit and explicit forms of control, and distributed planning and organizational self-design.
TL;DR: Having CD any time was associated with an increased rate of long-term functional problems in this depressed cohort, and girls who had attention deficit disorder seemed to be at higher risk for CD during study observation.
TL;DR: Evidence that nuclear reprogramming had taken place in nuclear transplant rabbits indicates that serial transfers could result in the expanded multiplication of mammalian embryos.
Abstract: The first six genetically verified nuclear transplant rabbits have been produced in this study. Individual eight-cell stage embryo blastomeres were transferred and fused with enucleated mature oocytes of which six full-term offspring were produced out of 164 manipulated eggs. The following efficiency rates were determined for the nuclear transplantation procedure: chromosomal removal from oocytes, 92%; fusion rate, 84%; activation rate, 46%; embryo transfer rate, 27%. Additional reasons for the low efficiency rate of nuclear transplant embryos may include limited development due to aging in recipient oocytes and asynchronous transfers of manipulated embryos to recipient females. The successful development to term may have been due to the ability of the mature oocyte to reprogram the eight-cell stage nuclei. The number of cells in blastocysts derived from isolated eight-cell blastomeres (18 +/- .08) was lower than that of nonmanipulated pronuclear (106 +/- 5.1) and nuclear transplant embryos derived from eight-cell stage nuclei (91 +/- 10.2) (p less than 0.001). This evidence along with the significant amount of nuclear swelling in nuclear transplant embryos and a delay in the time of blastocyst formation indicate that nuclear reprogramming had taken place in these embryos. Successful nuclear reprogramming indicates that serial transfers could result in the expanded multiplication of mammalian embryos.
TL;DR: Stress, a concept addressing the consequences of disruptive events on individuals and populations, can be a useful integrative idea as discussed by the authors, where adaptation focuses on "adaptive" or positive consequences, stress redresses an imbalance by focusing on the costs and limits of adaptation.
Abstract: Stress, a concept addressing the consequences of disruptive events on individuals and populations, can be a useful integrative idea. The stress process has much in common with its sister concept of adaptation. However, where adaptation focuses on “adaptive” or positive consequences, stress redresses an imbalance by focusing on the costs and limits of adaptation.
In this paper we first review the interdisciplinary roots of the stress concept. While most stress research derives from research in environmental physiology, Selyean concepts of stress (involving increased catecholamine and corticosteroid output) have forced an expansion toward greater concern for perceptual and psychosocial stressors. What is largely missing from all traditions, however, is concern for sociopolitical processes which are not easily adapted to and consequently are persistent and pervasive causes of stress.
Studies of stress in prehistoric, historical, and contemporary populations by biological anthropologists vary, in a complementary way, as to ability to delineate aspects of the stress process. Whereas the paleopathological methods of the prehistorian provide a suite of skeletal indicators of stress response, and the demographic measures of the historian provide a detailed analysis of consequence, a wide variety of techniques for examining all levels of the stress process are potentially available to those studying contemporary populations. In order to better utilize information from different levels of analysis one needs to focus on measures of stress, such as infant mortality, which are accessible at all levels. Biological anthropologists are in a unique position to elucidate the human condition if, via concepts such as stress, attention is paid to both human adaptive and political economic processes.
TL;DR: The results of theoretical and experimental studies of stabilizing and disruptive frequency-dependent selection in bacterial populations are reviewed and the importance of this kind of selection in the adaptation and evolution of these organisms and their accessory elements (plasmid, phage and transposons) is speculated.
Abstract: There are many situations in which the direction and intensity of natural selection in bacterial populations will depend on the relative frequencies of genotypes. In some cases, this selection will favour rare genotypes and result in the maintenance of genetic variability; this is termed stabilizing frequency-dependent selection. In other cases, selection will only favour genotypes when they are common. Rare types cannot invade and genetic variability will not be maintained; this is known as disruptive frequency-dependent selection. Phage-mediated selection for bacteria with novel restriction-modification systems is frequency-dependent and stabilizing. In mass culture, selection for the production of toxins and allelopathic agents is likely to be frequency-dependent but disruptive. This also occurs in selection favouring genes and transposable elements that cause mutations. Here I review the results of theoretical and experimental studies of stabilizing and disruptive frequency-dependent selection in bacterial populations, and speculate on the importance of this kind of selection in the adaptation and evolution of these organisms and their accessory elements (plasmid, phage and transposons).
03 Nov 1988
TL;DR: The Arcadia research project is investigating the construction of software environments that are tightly integrated, yet flexible and extensible enough to support experimentation with alternative software processes and tools.
Abstract: Early software environments have supported a narrow range of activities (programming environments) or else been restricted to a single “hard-wired” software development process. The Arcadia research project is investigating the construction of software environments that are tightly integrated, yet flexible and extensible enough to support experimentation with alternative software processes and tools. This has led us to view an environment as being composed of two distinct, cooperating parts. One is the variant part, consisting of process programs and the tools and objects used and defined by those programs. The other is the fixed part, or infrastructure, supporting creation, execution, and change to the constituents of the variant part. The major components of the infrastructure are a process programming language and interpreter, object management system, and user interface management system. Process programming facilitates precise definition and automated support of software development and maintenance activities. The object management system provides typing, relationships, persistence, distribution and concurrency control capabilities. The user interface management system mediates communication between human users and executing processes, providing pleasant and uniform access to all facilities of the environment. Research in each of these areas and the interaction among them is described.
TL;DR: The AIMS examination is best conducted within the context of an ongoing treatment program, the authors say, and should be part of the informed consent process necessary with patients treated with neuroleptic drugs.
Abstract: The Abnormal Involuntary Movement Scale (AIMS) examination has been widely recommended for periodic screening for tardive dyskinesia and follow-up of patients diagnosed with the disorder. However, few guidelines exist about how to use the examination in clinical practice. The authors discuss for whom, when, and how the AIMS examination can be used in a multidisciplinary setting; amplify the original instructions for the examination; and propose conventions to clarify scoring. Noting that the AIMS examination is not specific for tardive dyskinesia, they discuss a clinical approach to the patient who is found to have abnormal movements. The AIMS examination is best conducted within the context of an ongoing treatment program, the authors say, and should be part of the informed consent process necessary with patients treated with neuroleptic drugs.
TL;DR: The differential diagnosis includes other diseases characterized by PIE and the more recently recognized bronchiolitis obliterans and organizing pneumonia, a disorder which is also marked by peripheral pulmonary infiltrates.
TL;DR: Data suggest that vasopressin-sensitive neurons in the anterior hypothalamus are involved in the control of intraspecific aggression in male hamsters.
TL;DR: This paper reviewed findings from a panel study of Boston area unemployed men and their families and summarized the psychological effects of unemployment on workers and their wives, particularly for the first half year of joblessness.
Abstract: This paper reviews findings from a panel study of Boston area unemployed men and their families. Psychological effects of unemployment on workers and their wives are summarized, particularly for the first half year of joblessness. Family responses to job loss are also examined, including the role of the marital relationship in buffering workers' stress. Finally, policy and service implications of this research are discussed. Consideration is given not only to the mental health needs of workers, but to frequently overlooked qualities of efficacy and resilience among the unemployed.
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TL;DR: This paper presents a meta-modelling framework that automates the very labor-intensive and therefore time-heavy and expensive process of manually cataloging and cataloging individual objects in a scene.
Abstract: THE SCHEMA SYSTEM EMBODIES A KNOWLEDGE-BASED APPROACH TO SCENE INTERPRE- TATION. LOW-LEVEL ROUTINES ARE APPLIED TO EXTRACT IMAGE DESCRIPTORS CALLED TOKENS, AND THESE TOKENS ARE FURTHER ORGANIZED BY INTERMEDIATE-LEVEL ROUT- INES INTO MORE ABSTRACT STRUCTURES THAT CAN BE ASSOCIATED WITH OBJECT INST- ANCES. THE THOUSANDS OF TOKENS THAT ARE EXTRACTED FROM AN IMAGE CAN BE GROUPED IN A COMBINATORIALLY EXPLOSIVE MANNER. THEREFORE, KNOWLEDGE IN THE SCHEMA SYSTEM IS NOT LIMITED TO THE DESCRIPTIONS OF OBJECTS; IT INCLUDES INFORMATION ABOUT HOW EACH OBJECT CAN BE RECOGNIZED. OBJECT SCHEMAS CONTROL THE INVOCATION AND EXECUTION OF THE LOW-LEVEL AND INTERMEDIATE-LEVEL ROUT- INES WITH THE GOAL OF FORMING HYPOTHESES ABOUT OBJECTS IN THE SCENE. THE SYSTEM DESCRIBED PRODUCES IMAGE INTERPRETATIONS BASED ON TWO-DIMENSIONAL REASONING, ALTHOUGH NOTHING IN THE SYSTEM ORGANIZATION AND CONTROL STRATEG- IES PRECLUDE THE INCLUSION OF THREE-DIMENSIONAL INFORMATION. THE SCHEMA FRAMEWORK EXPLOITS COARSE-GRAINED PARALLELISM IN A COOPERA- TIVE INTERPRETATION PROCESS. SCHEMA INSTANCES RUN CONCURRENTLY, AND AN OB- JECT SCHEMA OFTEN HAS AVAILABLE A VARIETY OF STRATEGIES FOR IDENTIFICATION, EACH ONE INVOKING KNOWLEDGE SOURCES TO GATHER SUPPORT FOR THE PRESENCE OF A HYPOTHESIZED OBJECT. INTER-SCHEMA COMMUNICATION IS CARRIED OUT ASYNCHRON- OUSLY THROUGH A GLOBAL BLACKBOARD. IN THIS WAY SCHEMA INSTANCES COOPERATE TO IDENTIFY AND LOCATE THE SIGNIFICANT OBJECTS PRESENT IN THE SCENE.
TL;DR: This work formalizes a notion of loading information into connectionist networks that characterizes the training of feed-forward neural networks and introduces a perspective on shallow networks, called the Support Cone Interaction (SCI) graph, which is helpful in distinguishing tractable from intractable subcases.
TL;DR: Recombinant DNA clones encoding the neurotensin/neuromedin N precursor protein have been isolated from both bovine hypothalamus cDNA and rat genomic libraries using a heterologous canine cDNA probe suggesting that within a species identical precursors are synthesized in both the central nervous system and intestine.