Showing papers by "Columbia University published in 1989"

A 17,000-year glacio-eustatic sea level record: influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation

Abstract: Coral reefs drilled offshore of Barbados provide the first continuous and detailed record of sea level change during the last deglaciation. The sea level was 121 ± 5 metres below present level during the last glacial maximum. The deglacial sea level rise was not monotonic; rather, it was marked by two intervals of rapid rise. Varying rates of melt-water discharge to the North Atlantic surface ocean dramatically affected North Atlantic deep-water production and oceanic oxygen isotope chemistry. A global oxygen isotope record for ocean water has been calculated from the Barbados sea level curve, allowing separation of the ice volume component common to all oxygen isotope records measured in deep-sea cores.

Delay of gratification in children

Abstract: To function effectively, individuals must voluntarily postpone immediate gratification and persist in goal-directed behavior for the sake of later outcomes. The present research program analyzed the nature of this type of future-oriented self-control and the psychological processes that underlie it. Enduring individual differences in self-control were found as early as the preschool years. Those 4-year-old children who delayed gratification longer in certain laboratory situations developed into more cognitively and socially competent adolescents, achieving higher scholastic performance and coping better with frustration and stress. Experiments in the same research program also identified specific cognitive and attentional processes that allow effective self-regulation early in the course of development. The experimental results, in turn, specified the particular types of preschool delay situations diagnostic for predicting aspects of cognitive and social competence later in life.

A modified labeling theory approach to mental disorders : an empirical assessment

Abstract: Critics of labeling theory vigorously dispute Scheff's (1966) provocative etiological hypothesis and downplay the importance of factors such as stigma and stereotyping. We propose a modified labeling perspective which claims that even if labeling does not directly produce mental disorder, it can lead to negative outcomes. Our approach asserts that socialization leads individuals to develop a set of beliefs about how most people treat mental patients. When individuals enter treatment, these beliefs take on new meaning. The more patients believe that they will be devalued and discriminated against, the more they feel threatened by interacting with others. They may keep their treatment a secret, try to educate others about their situation, or withdraw from social contacts that they perceive as potentially rejecting. Such strategies can lead to negative consequences for social support networks, jobs, and self-esteem. We test this modified labeling perspective using samples of patients and untreated community residents, and find that both believe that "most people" will reject mental patients. Additionally, patients endorse strategies of secrecy, withdrawal, and education to cope with the threat they perceive. Finally, patients' social support networks are affected by the extent to which they fear rejection and by the coping responses they adopt to deal with their stigmatized status.

Developing critical thinkers: Challenging adults to explore alternative ways of thinking and acting.

Abstract: Part 1 Understanding critical thinking in adult life: what it means to think critically recognizing critical thinking learning to think critically in adult life how critical thinking sustains a healthy democracy. Part 2 Practical approaches for developing critical thinkers: effective strategies fro facilitating critical thinking helping others examine the assumptions underlying their thoughts and actions techniques for developing alternative ways of thinking. Part 3 Helping adults to think critically in different arenas of life: using the workplace as a resource for thinking and learning analyzing political issues and commitments developing critical judgements about television reporting encouraging active learning through personal relationships being a skilled facilitator of critical thinking. Epilogue: the risks and rewards to helping others learn to think critically. Abbreviations. References. Indexes: name subject.

Nuts and bolts for the social sciences

Abstract: This 1989 book is intended as an introductory survey of the philosophy of the social sciences. It is essentially a work of exposition which offers a toolbox of mechanisms - nuts and bolts, cogs and wheels - that can be used to explain complex social phenomena. Within a brief compass, Jon Elster covers a vast range of topics. His point of departure is the conflict we all face between our desires and our opportunities. How can rational choice theory help us understand our motivation and behaviour? More significantly, what happens when the theory breaks down but we still cleave to a belief in the power of the rational? Elster describes the fascinating range of forms of irrationality - wishful thinking, the phenomenon of sour grapes, discounting the future in noncooperative behaviour. This is a remarkably lucid and comprehensive introduction to the social sciences for students of political science, philosophy, sociology and economics.

Mitochondrial DNA Deletions in Progressive External Ophthalmoplegia and Kearns-Sayre Syndrome

Abstract: We investigated the correlations of deletions of mitochondrial DNA in skeletal muscle with clinical manifestations of mitochondrial myopathies, a group of disorders defined either by biochemical abnormalities of mitochondria or by morphologic changes causing a ragged red appearance of the muscle fibers histochemically. We performed genomic Southern blot analysis of muscle mitochondrial DNA from 123 patients with different mitochondrial myopathies or encephalomyopathies. Deletions were found in the mitochondrial DNA of 32 patients, all of whom had progressive external ophthalmoplegia. Some patients had only ocular myopathy, whereas others had Kearns-Sayre syndrome, a multisystem disorder characterized by ophthalmoplegia, pigmentary retinopathy, heart block, and cerebellar ataxia. The deletions ranged in size from 1.3 to 7.6 kilobases and were mapped to different sites in the mitochondrial DNA, but an identical 4.9-kilobase deletion was found in the same location in 11 patients. Biochemical analysis showed decreased activities of NADH dehydrogenase, rotenone-sensitive NADH-cytochrome c reductase, succinate-cytochrome c reductase, and cytochrome c oxidase, four enzymes of the mitochondrial respiratory chain containing subunits encoded by mitochondrial DNA. We conclude that deletions of muscle mitochondrial DNA are associated with ophthalmoplegia and may result in impaired mitochondrial function. However, the precise relation between clinical and biochemical phenotypes and deletions remains to be defined.

Consumer Preference Formation and Pioneering Advantage

Abstract: Market pioneers outsell later entrants in both consumer and industrial markets. Entry barriers arising from preemptive positioning and switching costs have been advanced to explain this market shar...

Linkage of a prion protein missense variant to Gerstmann–Sträussler syndrome

Abstract: Gerstmann-Straussler syndrome is a rare familial neurodegenerative condition that is vertically transmitted, in an apparently autosomal dominant way. It can also be horizontally transmitted to non-human primates and rodents through intracerebral inoculation of brain homogenates from patients with the disease. The exact incidence of the syndrome is unknown but is estimated to be between one and ten per hundred million. Patients initially suffer from ataxia or dementia and deteriorate until they die, in one to ten years. Protease-resistant prion protein (PrP) and PrP-immunoreactive amyloid plaques with characteristic morphology accumulate in the brains of these patients. Current diagnostic criteria for Gerstmann-Straussler syndrome incorporate clinical and neuropathological features, as animal transmission studies can be unreliable. PrP is implicated in the pathogenesis and transmission of the condition and in scrapie, an equivalent animal disease. It was discovered by enriching scrapie-infected hamster brain fractions for infectivity. Because there is compelling evidence that the scrapie isoform of PrP is a necessary component of the infectious particle, it seemed possible that the PrP gene on the short arm of human chromosome 20 in Gerstmann-Straussler syndrome might be abnormal. We show here that PrP codon 102 is linked to the putative gene for the syndrome in two pedigrees, providing the best evidence to date that this familial condition is inherited despite also being infectious, and that substitution of leucine for proline at PrP codon 102 may lead to the development of Gerstmann-Straussler syndrome.

Strategic Change: The Effects Of Founding And History

Abstract: The research reported here examined the evolution of strategy over time and the conditions under which change in strategy is likely. Findings show that characteristics of an organization's founding imprint its initial strategy by contributing to an internal consensus around a given strategic approach. Conditions subsequent to founding also influence the degree to which an initial strategy is perpetuated. The study examined perspectives on organizational change and inertia and further developed them to explain the role of history and precedence in shaping strategic action.

Children and adults as intuitive scientists.

Abstract: The metaphor of children and lay adults as intuitive scientists has gained wide acceptance. Although useful in one sense, pertaining to scientific understanding, in another, pertaining to the process of scientific thinking, the metaphor may be fundamentally misleading. Research is reviewed indicating that processes of scientific thinking differ significantly in children, lay adults, and scientists. Hence, it is the instruments of scientific thinking, not just the products, that undergo "strong restructuring" (Carey, 1986). A framework for conceptualizing development of scientific thinking processes is proposed, centering on progressive differentiation and coordination of theory and evidence. This development is metacognitive, as well as strategic. It requires thinking about theories, rather than merely with them, and thinking about evidence, rather than merely being influenced by it, and, hence, reflects the attainment of control over the interaction of theories and evidence in one's own thinking. The metaphor of the lay adult—or the child—as an intuitive scientist has gained wide acceptance in the last decade. As the scientist explores the environment, constructs models as a basis for understanding it, and revises those models as new evidence is generated, so do lay people endeavor to make sense of their environments by processing data and constructing mental models based on these data. The highly influential volume by Nisbett and Ross (1980) and seminal research by Tversky and Kahneman that is highlighted in the Nisbett and Ross book have done much to promote the metaphor. More recently, it has been promoted as well by the literature on scientific understanding and conceptual change, discussed later, and to an extent by the general theory of induction proposed by Holland, Holyoak, Nisbett, and Thagard (1986), a theory whose principles are intended to apply to all forms of induction from the very simplest forms of concept formation to the thinking of scientists. As the research summarized by Nisbett and Ross documents, the particular inference rules that the intuitive scientist uses to interpret evidence and make inductive inferences are likely to be faulty. The intuitive scientist, for example, makes inferences based on insufficient sample size and overlooks base rates. Nevertheless, the process and goal of this intuitive scientific activity are thought to be analogous in the layperson and the professional scientist. In this article, I have a particular concern with the thinking of children and the ways in which it may or may not resemble that of scientists. I therefore focus on the metaphor of child as scientist, although I consider as well the thinking of lay adults and its resemblance to that of scientists. I explore two quite different senses in which this metaphor might be taken and conclude that, although it may be useful and productive in one sense, the child-as-scientist metaphor in another sense may be fundamentally misleading.

Chief executive compensation: A study of the intersection of markets and political processes

Abstract: A model of the determinants of chief executive (CEO) compensation is presented and tested. Based on a sample from the leisure industry, the study finds that CEO pay has complex links to several factors: firm size, complexity, performance, CEO power, board vigilance, and the CEO's human capital. The study includes a separate examination of CEO salary and bonus, as well as a test of pay determination across McEachern's (1975) ownership categories.

Infection-resistant compositions, medical devices and surfaces and methods for preparing and using same

Abstract: A method of preparing an infection-resistant medical device comprising one or more matrix-forming polymers selected from the group consisting of biomedical polyurethane, biomedical silicones and biodegradable polymers, and antimicrobial agents, especially a synergistic combination of a silver salt and chlorhexidine (or its salts); also disclosed are medical devices having the synergistic composition therein or compositions thereon

Studies of aglycosylated chimeric mouse-human IgG. Role of carbohydrate in the structure and effector functions mediated by the human IgG constant region.

Abstract: Chimeric mouse-human IgG was used to study the structural and functional roles of the carbohydrate present in the CH2 domain of human IgG molecules. To remove this N-linked carbohydrate, Asn-297, the oligosaccharide attachment residue, was changed to either Gln (a conservative replacement) or His for IgG1 or Lys for IgG3 (nonconservative replacements) by site-directed mutagenesis. Carbohydrate-deficient antibodies are properly assembled and secreted and bind Ag and protein A. However, aglycosylated IgG are more sensitive to most proteases than their corresponding wild-type IgG, indicating some conformational changes have occurred. Aglycosylated IgG do not bind to the human Fc gamma RI and do not activate C; depending on the isotype, C1q binding ability is either completely lost (IgG1) or dramatically decreased (IgG3). The serum half-life in mice of aglycosylated IgG1-Gln remains the same as wild-type IgG1, 6.5 +/- 0.5 days, whereas aglycosylated IgG3-Gln has a shorter half-life, 3.5 +/- 0.2 days, compared to that of wild-type IgG3, 5.1 +/- 0.4 days. These results indicate the carbohydrate interposed between CH2 domain of human IgG is necessary to maintain the appropriate structure for the maintenance of many of the effector functions dependent on the CH2 domain.

An autosomal dominant disorder with multiple deletions of mitochondrial DNA starting at the D-loop region.

Abstract: DELETIONS of muscle mitochondrial DNA (mtDNA) have recently been found in patients with mitochondrial myopathy1–3. However, as most of the described cases were sporadic, and individual deletions involved different portions of mtDNA1,2, the mechanism(s) producing the molecular lesions, as well as their mode of transmission, remain unclear. By studying families with mtDNA heteroplasmy4, valuable information can be obtained about the role of inheritable factors in the pathogenesis of these disorders. We have studied four members of a family with autosomal dominant mitochondrial myopathy. Multiple deletions, involving the same portion of muscle mtDNA, were identified in all patients. Sequence analysis of the mutant mtDNAs, performed after DNA amplification by the polymerase-chain reaction showed that all the deletions start within a 12-nucleotide stretch at the 5′ end of the D-loop region, a site of active communication between the nucleus and the mtDNA. The data indicate that a mutation of a nuclear-coded protein can destroy the integrity of the mitochondrial genome in a specific, heritable way.

Global patterns of tectonic stress

Abstract: Regional patterns of present-day tectonic stress can be used to evaluate the forces acting on the lithosphere and to investigate intraplate seismicity. Most intraplate regions are characterized by a compressional stress regime; extension is limited almost entirely to thermally uplifted regions. In several plates the maximum horizontal stress is subparallel to the direction of absolute plate motion, suggesting that the forces driving the plates also dominate the stress distribution in the plate interior.

Crystal structure of core streptavidin determined from multiwavelength anomalous diffraction of synchrotron radiation.

Abstract: A three-dimensional crystal structure of the biotin-binding core of streptavidin has been determined at 3.1-A resolution. The structure was analyzed from diffraction data measured at three wavelengths from a single crystal of the selenobiotinyl complex with streptavidin. Streptavidin is a tetramer with subunits arrayed in D2 symmetry. Each protomer is an 8-stranded beta-barrel with simple up-down topology. Biotin molecules are bound at one end of each barrel. This study demonstrates the effectiveness of multiwavelength anomalous diffraction (MAD) procedures for macromolecular crystallography and provides a basis for detailed study of biotin-avidin interactions.

Suicidal Ideation and Suicide Attempts in Panic Disorder and Attacks

Abstract: Panic disorder, which is found in about 1.5 percent of the population at some time in their lives, includes recurrent episodes of sudden, unpredictable, intense fear accompanied by symptoms such as palpitations, chest pain, and faintness. Panic attacks, which do not meet these diagnostic criteria fully, are two to three times more prevalent. Since panic symptoms can mimic those of other medical disorders, patients with these symptoms use medical services frequently. To determine the risk of suicidal ideation and suicide attempts in panic disorder and attacks, we studied a random sample of 18,011 adults drawn from five U.S. communities. Subjects who had panic disorder, as compared with other psychiatric disorders, had more suicidal ideation and suicide attempts, with an adjusted odds ratio for suicide attempts of 2.62 (95 percent confidence interval, 1.83 to 3.74). The odds ratio was 17.99 (95 percent confidence interval, 12.18 to 26.58) when the group with panic disorder was compared with subjects who had no psychiatric disorder. Twenty percent of the subjects with panic disorder and 12 percent of those with panic attacks had made suicide attempts. These results could not be explained by the coexistence of major depression or of alcohol or drug abuse. We conclude that panic disorder and attacks are associated with an increased risk of suicidal ideation and suicide attempts. Physicians working in general medical settings and emergency departments should be alert to this problem.

Latitudinal variations in plankton δ 13 C: implications for CO 2 and productivity in past oceans

Abstract: Low C-13/C-12 in present-day Antarctic plankton has been ascribed to high CO2 availability. It is reported here, however, that this high-latitude C-13 depletion develops at CO2 partial pressures that are often below that of the present atmosphere and usually below that of equatorial upwelling systems. Nevertheless, because of much lower water temperatures and hence greater CO2 solubility at high latitude, the preceding pCO2 measurements translate into Antarctic surface-water CO2 (aq) concentrations that are as much as 2.5 times higher than in equatorial waters. It is calculated that an oceanic pCO2 level greater than 800 micro-atm is a warmer low-latitude Cretaceous ocean would have been required to produce the plankton C-13 depletion preserved in Cretaceous sediments.

Selective loss of hippocampal granule cells in the mature rat brain after adrenalectomy.

Abstract: Adrenalectomy of adult male rats resulted in a nearly complete loss of hippocampal granule cells 3 to 4 months after surgery. Nissl and immunocytochemical staining of hippocampal neurons revealed that the granule cell loss was selective; there was no apparent loss of hippocampal pyramidal cells or of gamma-amino butyric acid (GABA)-, somatostatin-, neuropeptide Y-, calcium binding protein-, or parvalbumin-containing hippocampal interneurons. The hippocampal CA1 pyramidal cells of adrenalectomized animals exhibited normal electrophysiological responses to afferent stimulation, whereas responses evoked in the dentate gyrus were severely attenuated. Corticosterone replacement prevented both the adrenalectomy-induced granule cell loss and the attenuated physiological response. Thus, the adrenal glands play a role in maintaining the structural integrity of the normal adult brain.

Intertemporally Dependent Preferences and the Volatility of Consumption and Wealth

Abstract: In this article we construct a model in which a consumer’s utility depends on the consumption history We describe a general equilibrium framework similar to Cox, Ingersoll, and Ross (1985a). A simple example is then solved in closedform in this general equilibrium setting to rationalize the observed stickiness of the consumption series relative to the fluctuations in stock market wealth. The sample paths of consumption generated from this model imply lower variability in consumption growth rates compared to those generated by models with separable utilizations. We then present a partial equilibrium model similar to Merton (1969, 1971) and extend Merton’s results on optimal consumption and portfolio rules to accommodate nonseparability in preferences. Asset pricing implications of our framework are briefly explored.

A direct repeat is a hotspot for large-scale deletion of human mitochondrial DNA

Abstract: Kearns-Sayre syndrome (KSS) and progressive external ophthalmoplegia (PEO) are related neuromuscular disorders characterized by ocular myopathy and ophthalmoplegia. Almost all patients with KSS and about half with PEO harbor large deletions in their mitochondrial genomes. The deletions differ in both size and location, except for one, 5 kilobases long, that is found in more than one-third of all patients examined. This common deletion was found to be flanked by a perfect 13-base pair direct repeat in the normal mitochondrial genome. This result suggests that homologous recombination deleting large regions of intervening mitochondrial DNA, which previously had been observed only in lower eukaryotes and plants, operates in mammalian mitochondrial genomes as well, and is at least one cause of the deletions found in these two related mitochondrial myopathies.