Showing papers by "University of Rochester published in 1977"

The need for a new medical model: a challenge for biomedicine

Abstract: The dominant model of disease today is biomedical, and it leaves no room within tis framework for the social, psychological, and behavioral dimensions of illness. A biopsychosocial model is proposed that provides a blueprint for research, a framework for teaching, and a design for action in the real world of health care.

Photon Antibunching in Resonance Fluorescence

Abstract: The phenomenon of antibunching of photoelectric counts has been observed in resonance fluorescence experiments in which sodium atoms are continuously excited by a dye-laser beam. It is pointed out that, unlike photoelectric bunching, which can be given a semiclassical interpretation, antibunching is understandable only in terms of a quantized electromagnetic field. The measurement also provides rather direct evidence for an atom undergoing a quantum jump.

Development of β-adrenergic receptor subsensitivity by antidepressants

Abstract: CONSIDERABLE evidence exists that the tricyclic antidepressant drugs are selective inhibitors of monoamine uptake into monoaminergic nerve terminals1,2. These drugs also potentiate pharmacological responses to the monoamines in both the peripheral and central nervous systems3–6. These effects do not explain the discrepancy between the time-course of the biochemical and pharmacological responses which are elicited by these antidepressant drugs within minutes or hours and their clinical antidepressant action which requires treatment for weeks for efficacy to be reached. Furthermore, desipramine, an antidepressant drug, can potentiate neuronal responses to noradrenaline and dopamine in the caudate nucleus7, although it does not block the catecholamine uptake in this area of the brain1,2. Finally the antidepressant iprindole does not influence noradrenaline turnover8 or metabolism9,10 or its uptake into catecholaminergic neurones11, but is effective in potentiating the responses of single cortical and caudate neurones to monoamines12. Vetulani and his associates13 suggested that the therapeutic action of tricyclic antidepressants may be related to postsynaptic adaptive changes in the sensitivity of the noradrenergic adenylate cyclase receptor system rather than to acute presynaptic events. The purpose of the experiments described here was to explore the molecular basis for antidepressant-induced noradrenergic subsensitivity by examining the kinetic properties of the β-adrenergic receptors in the microsomal suspension of rat brain by using a potent β-adrenergic receptor antagonist 3H-dihydroalprenolol as a radiolabelled ligand14–19. Our results indicate that the main mechanism is a reduction in the number of receptors.

Prediction of outcome in schizophrenia. III. Five-year outcome and its predictors.

Abstract: † Recent studies of schizophrenia have begun to demonstrate the complex nature of its outcome characteristics and their predictors. However, generalization of findings has been limited by methodological problems such as relatively short-term followup, the use of retrospective data, or employment of evaluation techniques without demonstrated reliability. This report describes a prospective, five-year follow-up using reliable evaluation techniques to determine whether specific relations between predictors and outcome variables represent behavior patterns persisting over an extended period. Results demonstrate the prognostic importance and specificity of certain predictors over five years. These results support the view that outcome function is comprised of persisting open-linked systems of behavior.

The time-dependent physical spectrum of light*

Abstract: We investigate the time-dependent spectrum of light from an observational point of view and define a time-dependent “physical spectrum” of light based on the counting rate of a photodetector. The tunable element, the filter, that allows observation of different spectral components of the light is shown to play an essential role in the time-dependent spectrum. Its bandwidth cannot be taken arbitrarily narrow. We establish the connection between our physical spectrum and other time-dependent spectra associated with Page, Lampard, Silverman, and Kolmogorov, as well as with the Wiener-Khintchine power spectrum. Also, we show the conditions under which these earlier definitions can be used as the first approximations to the complete physical spectrum, and give an expression for the correction terms.

Toward the operational identification of adverse drug reactions.

Abstract: The evaluation of adverse drug reactions in clinical practice is somewhat arbitrary and is characterized by considerable differences of opinion. This report presents a decision table algorithm approach toward the development of an operational system for the identification of adverse drug reactions. The algorithm incorporates an estimate of the certainty of the link between the untoward clinical event and the suspect drug, and examines the underlying causes of the identified drug reactions. Use of such a system is a first step toward reducing ambiguity in the evaluation of adverse drug reactions.

Chlorinated biphenyl induction of aryl hydrocarbon hydroxylase activity: a study of the structure-activity relationship.

Abstract: Of 16 halogenated biphenyls examined for their capacity to induce hepatic aryl hydrocarbon hydroxylase activity in the chicken embryo, only three congeners, 3,4,39,49-tetrachlorobiphenyl, 3,4,5,39,49,59-hexachlorobiphenyl, and 3,4,5,39,49,59-hexabromobiphenyl, were active. They were approximately equipotent in the chicken embryo, with ED50 values of approximately 90 nmoles/kg. These three chlorobiphenyl congeners also induced hepatic aryl hydrocarbon hydroxylase activity in C57BL/6J mice and rats, and they competitively bound the hepatic cytosol binding species thought to be the receptor for the induction of this enzyme. Among the halogenated biphenyls, there appear to be two structural requirements for induction of aryl hydrocarbon hydroxylase activity: the presence of at least 2 adjacent halogen atoms in the lateral positions of each benzene ring (positions 3,4,39,49 or 3,4,5,39,49,59) and the absence of halogen atoms adjacent to the biphenyl bridge (positions 2,6,29, and 69); such substitutions lead to marked nonplanarity of the molecule. The halobiphenyl congeners that induced aryl hydrocarbon hydroxylase activity did not induce aminopyrine N-demethylase activity (a measure of phenobarbital-like activity); however, some of the congeners that failed to induce aryl hydrocarbon hydroxylase activity did induce aminopyrine N-demethylase. This suggests that while the commercial mixture of chlorobiphenyls, Aroclor 1254, induces a mixed pattern of microsomal monooxygenase activity resembling the combined administration of 3-methylcholanthrene and phenobarbital, any given chlorobiphenyl congener appears to produce only a 3-methylcholanthrene-like or a phenobarbital-like response (or the congener may be devoid of both activities). 3,4,39,49-Tetrachlorobiphenyl, the prototype of the halobiphenyls that induce hepatic aryl hydrocarbon hydroxylase activity, is an approximate isostereomer of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,7,8-tetrachlorodibenzofuran, and 3,4,39,49-tetrachloroazoxybenzene, all of which induce hepatic aryl hydrocarbon hydroxylase activity but which are over 100-fold more potent. Conversion of 3,4,39,49-tetrachlorobiphenyl to a more rigid, planar analogue, 2,3,6,7-tetrachlorobiphenylene, produced a compound roughly equipotent to TCDD in inducing hepatic aryl hydrocarbon hydroxylase activity in the chicken embryo.

Storage-Retrieval Interleaving in Automatic Warehousing Systems

Abstract: This paper extends work previously reported on storage assignment rules for automatic warehousing systems to include interleaving; that is, the sequencing of storage and retrieve requests. Using both continuous analytical models and discrete evaluation procedures, this paper compares the operating performance of several storage assignment/interleaving policies. The results indicate that significant reductions in crane travel time and distance are obtainable in some real-world and/or previously modeled situations via the proposed storage assignment/interleaving policies. These reductions may be directly translated into increased throughput capacity for existing systems. The storage assignment/interleaving policies may also be used to improve the design of proposed systems to achieve a more desirable balance between throughput and storage capacity. Although the system examined is a high-rise automatic warehouse, the results presented have implications for the warehousing function in general.

Impression creep; a new creep test

Abstract: A new indentation creep test is introduced in which the indenter is a circular cylinder with a flat end Unlike conventional indentation tests, a steady-state velocity is observed in this new test shortly after a transient period during which the indenter makes a shallow impression on the surface of the specimen; hence the name “impression creep” This steady-state velocity is found to have the same stress and temperature dependences as the conventional undirectional creep tests using bulk specimens Three possible mechanisms are analysed in detail, bulk diffusion, surface diffusion, and dislocation creep They have different stress and indenter-size (radius) dependences Experimental results on succinonitrile crystals are reported

Coherence and radiometry with quasihomogeneous planar sources

Abstract: The concept of a quasihomogeneous source is introduced. Unlike a source that is strictly homogeneous in its statistical properties, a quasihomogeneous source may be finite. Many physical sources, both primary and secondary ones, are adequately approximated by this model. Coherence and radiometric properties of light generated by such sources (assumed, for simplicity, to be planar) are discussed and an important reciprocity relation is shown to exist between light in the far zone and in the source plane. This relation implies that the degree of coherence in the far zone is given by the classic form of the van Cittert-Zernike theorem, even though the source may have a high degree of spatial coherence over arbitrarily large areas. The reciprocity relation also provides a generalization of a recently derived result that expresses the angular dependence of the radiant intensity in terms of the degree of spatial coherence of light in the source plane. The dependence of all the basic radiometric quantities on the distribution of the optical intensity across the source and on the degree of spatial coherence of the light emerging from the source is discussed and is illustrated, for some typical sources, by computed curves.

Radiocarbon Dating Using Electrostatic Accelerators: Negative Ions Provide the Key

Abstract: Mass spectrometric methods have long been suggested as ways of measuring14C/12C ratios for carbon dating. One problem has been to distinguish between14N and14C. With negative ions and a tandem electrostatic accelerator, the14N background is virtually absent and fewer than three14C atoms in 1016atoms of12C have been easily measured.

Human gastric pacesetter potential: Site of origin, spread, and response to gastric transection and proximal gastric vagotomy

Abstract: Gastric electrical activity was recorded from twenty-six patients at celiotomy. The human gastric pacemaker was localized to an area in the midcorpus along the greater curve. Pacesetter potentials were generated regularly by the pacemaker at a mean frequency of 3.2 cycles/min and were propagated circumferentially and aborally from the pacemaker, increasing in amplitude and velocity as they approached the pylorus. The pattern of pacesetter potentials in patients with gastric ulcer, gastric cancer, and duodenal ulcer was similar to that of patients without such diseases. Complete transection of the gastric corpus isolated the distal stomach from the natural pacemaker and resulted in the appearance of a new pacemaker in the distal stomach with a slower frequency. The fact that proximal gastric vagotomy did not greatly alter the frequency of generation or the pattern of propagation of the pacesetter potential provided further evidence that both are myogenic phenomena.

Sex differences in social participation

Abstract: Twenty female and 38 male first-year college students maintained a daily record of their social interactions for 2 weeks early in the fall semester and for 2 weeks late in the spring semester. Over all interactions, females decreased time per day in interaction more than males did, primarily by reducing the length of interactions, and reported decreased satisfaction with these interactions. In interactions with three best same-sex friends, females also decreased length more than males did but maintained a higher level of satisfaction Number of interactions with same-sex best friend decreased markedly for females but not for males. The results were interpreted as showing that females socialize more intensely in the new environment than males and make use of the same-sex best friend to deal with the social stimulation. Differences between the sexes on interaction measures in the spring were minimal. Social psychology is often denned as the study of social interaction, and social psychologists do indeed study social interaction in a variety of ways. Strangely enough, however, social scientists in general are hard pressed to answer some of the most basic questions about social interaction: questions such as how much time during a day do people spend in social interaction? With how many different people do they interact? How long is the average interaction? How many people are involved in the typical social encounter, and what is its sexual composition? What differences exist among people in their reactions to their social lives? For each of these questions and the many others that could be asked, a second question immediately follows: In what ways, if any, do males and females differ in their social behavior? Using sex-based characteristics is a nearly universal way of describing

Visual attention in reading: Eye movements reflect cognitive processes.

Abstract: Two hypotheses regarding the nature of fixation durations in reading were discussed. One position suggests that semantic processing lags behind the perceptual input of information. The other position suggests that semantic processing is more rapid and immediate. Eye movement data of skilled readers reading passages of text were analyzed. It was found that the main verb of the sentence received more visual attention than other key grammatical elements within a sentence. On the basis of the overall result pattern, it was argued that eye movements are affected by cognitive processes occurring at the time of the fixations.

U.S. House Members in Their Constituencies: An Exploration

Abstract: The paper addresses itself to two questions left underdeveloped in the literature on representative-constituent relations. First, what does the representative see when he or she sees a constituency? Second, what consequences do these perceptions have for his or her behavior? The paper reverses the normal Washington-oriented view of representative-constituent relations and approaches both questions by examining the representative in his or her constituency. The paper's observations are drawn from the author's travels with seventeen U.S. House members while they were working in their districts. Member perceptions of their constituency are divided into the geographical, the reelection, the primary and the personal constituencies. Attention is then given to the home style of House members. Home style is treated as an amalgam of three elements – allocation of resources, presentation of self, explanation of Washington activity. An effort is made to relate home style to the various perceived constituencies. Some observations are made relating constituency-oriented research to the existing literature on representation.

Isolation and characterization of MMS-sensitive mutants of Saccharomyces cerevisiae

Abstract: We have isolated mutants sensitive to methyl methanesulfonate (MMS) in Saccharomyces cerevisiae. Alleles of rad1, rad4, rad52, rad55 and rad57 were found amoung these mms mutants. Twenty-nine of the mms mutants which complement the existing radiation-sensitive (rad and rev) mutants belong to 22 new complementation groups. Mutants from five complementation groups are sensitive only to MMS. Mutants of 11 complementation groups are sensitive to UV or X rays in addition to MMS, mutants of six complementation groups are sensitive to all three agents. The cross-sensitivities of these mms mutants to UV and X rays are discussed in terms of their possible involvement in DNA repair. Sporulation is reduced or absent in homozygous diploids of mms mutants from nine complementation groups.

An Epidemiologic Study of Migraine and Headache in 10–20 Year Olds

Abstract: SYNOPSIS Headache histories of a random sample of 600 ten to twenty year-olds were obtained by standard interview and questionnaires were completed independently by the parents of those aged ten to fifteen. Parental headache histories and clinical evaluations were obtained on subsamples. Migraine was defined as headache with two of three features: unilaterality, nausea, or neurologic manifestations. The prevalence of migraine was higher in females but did not vary significantly with age, social class, menstrual status or history of cyclic or nervous vomiting, travel sickness or recurrent abdominal pain. The familial pattern of migraine was evident. Interview of ten to fifteen year-olds for history of unilateral headache or neurologic features was more sensitive than questioning their parents. Development and proper documentation of standard and reliable methods for headache identification are a prerequisite for the reliability and comparability of both clinical and epidemiologic studies of headache

Geometric Modeling of Mechanical Parts and Processes

Abstract: Geometry plays a crucial role in nearly all design and production activities in the discrete goods industries. Curiously, these industries' primary means for specifying geometry—two-dimensional graphics—has not changed significantly for more than a century. Dramatic changes are likely to occur in the next decade, however, because the deficiencies of current methods are retarding the progress of automation and are stimulating the development of new, computationally oriented schemes for handling mechanical geometry.