Showing papers by "University of Minnesota published in 1979"

Remote sensing and image interpretation

Abstract: A textbook prepared primarily for use in introductory courses in remote sensing is presented. Topics covered include concepts and foundations of remote sensing; elements of photographic systems; introduction to airphoto interpretation; airphoto interpretation for terrain evaluation; photogrammetry; radiometric characteristics of aerial photographs; aerial thermography; multispectral scanning and spectral pattern recognition; microwave sensing; and remote sensing from space.

Circumplex Model of Marital and Family Systems: I. Cohesion and Adaptability Dimensions, Family Types, and Clinical Applications

Abstract: The conceptual clustering of numerous concepts from family therapy and other social science fields reveals two significant dimensions of family behavior, cohesion and adaptability. These two dimensions are placed into a circumplex model that is used to identify 16 types of marital and family systems. The model proposes that a balanced level of both cohesion and adaptability is the most functional to marital and family development. It postulates the need for a balance on the cohesion dimension between too much closeness (which leads to enmeshed systems) and too little closeness (which leads to disengaged systems). There also needs to be a balance on the adaptability dimension between too much change (which leads to chaotic systems) and too little change (which leads to rigid systems). The model was developed as a tool for clinical diagnosis and for specifying treatment goals with couples and families.

Virus-associated hemophagocytic syndrome: a benign histiocytic proliferation distinct from malignant histiocytosis.

Abstract: Nineteen patients whose bone marrow smears showed histiocytic hyperplasia with prominent hemophagocytosis were found to have a clinicopathologic syndrome associated with active viral infection. High fever, constitutional symptoms, liver function, and coagulation abnormalities and peripheral blood cytopenias were characteristic findings. Hepatosplenomegaly, lymphadenopathy, bilateral pulmonary infiltrates, and skin rash were often present. Fourteen of the patients were immunosuppressed. Active infection by herpes group viruses was documented in 14 patients and by adenovirus in 1. The bone marrow of most patients also showed decreased granulopoiesis and erythropoiesis with normal to increased numbers of megakaryocytes. Treatment generally consisted of supportive therapy and withdrawal of immunosuppressive drugs. Thirteen patients recovered. Lymph node biopsy and autopsy material showed generalized histiocytic hyperplasia with hemophagocytosis. The relationship of this disorder to familial hemophagocytic reticulosis, familial erythrophagocytic lymphohistiocytosis, histiocytic medullary reticulosis, and malignant histiocytosis is discussed. Immunosuppressive and cytotoxic therapy may be contraindicated in the treatment of this virus-associated syndrome.

A Predictive Approach to Model Selection

Abstract: This article offers a synthesis of Bayesian and sample-reuse approaches to the problem of high structure model selection geared to prediction. Similar methods are used for low structure models. Nested and nonnested paradigms are discussed and examples given.

Self-monitoring processes

Abstract: Publisher Summary The chapter discusses the identification, consequences, and processes of self-monitoring. Empirical research on self-monitoring processes began with the construction and validation of the Self-Monitoring Scale, an instrument designed to translate the self-monitoring construct in an instrument that reliably and validly identifies it. Self-monitoring is the proposition that individuals can and should exercise control over their expressive behavior, self-presentation, and nonverbal displays of affect. Self-monitoring processes meaningfully channel and influence worldviews, behavior in social situations, and the unfolding dynamics of interactions with other individuals. It is the intent of this chapter to trace the origins and development of the social psychological construct of self-monitoring, to chart the behavioral and interpersonal consequences of self-monitoring, and to probe the cognitive and psychological processes of self-monitoring. The chapter provides some guidelines for conceptualizing and investigating the interplay of individuals and their situations.

Space and Place: Humanistic Perspective

Abstract: Space and place together define the nature of geography. Spatial analysis or the explanation of spatial organisation is at the forefront of geographical research. Geographers appear to be confident of both the meaning of space and the methods suited to its analysis. The interpretation of spatial elements requires an abstract and objective frame of thought, quantifiable data, and ideally the language of mathematics. Place, like space, lies at the core of geographical discipline. Indeed an Ad Hoc Committee of American geographers (1965, 7) asserted that “the modern science of geography derives its substance from man’s sense of place”. In the geographical literature, place has been given several meanings (Lukermann, 1964; May, 1970). As location, place is one unit among other units to which it is linked by a circulation net; the analysis of location is subsumed under the geographer’s concept and analysis of space. Place, however, has more substance than the word location suggests: it is a unique entity, a ‘special ensemble’ (Lukermann, 1964, p. 70); it has a history and meaning. Place incarnates the experiences and aspirations of a people. Place is not only a fact to be explained in the broader frame of space, but it is also a reality to be clarified and understood from the perspectives of the people who have given it meaning.

Influential Observations in Linear Regression

Abstract: Characteristics of observations which cause them to be influential in a least squares analysis are investigated and related to residual variances, residual correlations, and the convex hull of the observed values of the independent variables. It is shown how deleting an observation can substantially alter an analysis by changing the partial F-tests, the studentized residuals, the residual variances, the convex hull of the independent variables, and the estimated parameter vector. Outliers are discussed briefly, and an example is presented.

On the determination of Born–Oppenheimer nuclear motion wave functions including complications due to conical intersections and identical nuclei

Abstract: We show how the presence of a conical intersection in the adiabatic potential energy hypersurface can be handled by including a new vector potential in the nuclear‐motion Schrodinger equation. We show how permutational symmetry of the total wave function with respect to interchange of nuclei can be enforced in the Born–Oppenheimer approximation both in the absence and the presence of conical intersections. The treatment of nuclear‐motion wave functions in the presence of conical intersections and the treatment of nuclear‐interchange symmetry in general both require careful consideration of the phases of the electronic and nuclear‐motion wave functions, and this is discussed in detail.

Malignant small cell tumor of the thoracopulmonary region in childhood. A distinctive clinicopathologic entity of uncertain histogenesis

Abstract: This report describes a unique clinicopathologic entity characterized as a malignant small cell tumor of the thoracopulmonary region in 20 children and adolescents (average age 14.5 years). There was a female predilection (75%) for this tumor which appeared to originate in the soft tissues of the chest wall or the peripheral lung. The neoplasm tended to recur locally and did not seem to disseminate as widely as some of the other small cell tumors of childhood (rhabdomyosarcoma, Ewing's sarcoma, neuroblastoma and malignant lymphoma). However, the median survival was only 8 months. Electron microscopy of 3 cases suggested a neuroepithelial derivation, but, at the present, the histogeneis remains a subject for further investigation.

Thyroid hormone action at the cellular level

Abstract: A large body of circumstantial evidence suggests that the basic unit of thyroid hormone action is the triiodothyronine nuclear receptor complex. This complex stimulates the formation, directly or indirectly, of a diversity of messenger RNA (mRNA) sequences. A generalized increase in mRNA as well as a disproportionate increase in a limited number of RNA sequences have been demonstrated. Regulation of thyroid hormone effects may be carried out largely at a local cellular level. Highly selective alterations in sensitivity to the triiodothyronine nuclear receptor complex may occur at specific target genes. Metabolic factors and hormones participate in such regulation. In a given tissue, alterations in the total number of receptor sites has not been shown to be useful as an index of thyroid hormone response, and local modulation of the response to the triiodothyronine receptor complex by a variety of factors other than triiodothyronine may be carried out at a postreceptor level.

Criterion of minimum state density in the transition state theory of bimolecular reactions

Abstract: We discuss two minimum‐density‐of‐states criteria for the location of generalized transition states for chemical reactions. One is due to Bunker and Pattengill; the other is due to Wong and Marcus. We prove that both provide upper bounds on the exact classical equilibrium rate constant. In addition, we show that for several‐dimensional systems both methods are exact at threshold, and in the limit of an infinite number of dimensions they agree with the variational theory of reactions of Wigner, Horiuti, and Keck. However, it is also shown that for a finite number of degrees of freedom both methods yield rate constants which are only as accurate as or less accurate than rate constants given by the variational theory of reactions. We note that, where tested by others for actual systems, the differences of the results obtained with the variational and Bunker–Pattengill criteria have been minor.

An Outbreak of Infections Caused by Strains of Staphylococcus aureus Resistant to Methicillin and Aminoglycosides. I. Clinical Studies

Abstract: In a 22-month period, strains of Staphylococcus aureus resistant to methicillin and multiple aminoglycosides, (designated MARS) were recovered from 108 inpatients with nosocomial infections at a hospital in the midwestern United States. Sixty-six of these patients were staying in a burn unit, and 42 were on other hospital wards. Among the patients with burns, MARS were recovered from the burn wounds of 64%; 32% of the patients with burns had MARS bacteremia. The patients without burns were age-matched with patients with nosocomial infections caused by antibiotic-susceptible strains of S. aureus. Patients from whom MARS were isolated had a longer mean hospital stay (79.6 days vs. 36.9 days; P less than 0.01), developed infection later (26.5 days vs. 13.5 days after admission; P less than 0.01), and had received antibiotic therapy before infection more often (81% vs. 38% of patients; P less than 0.01) than patients in the comparative population. Types of infection and incidences of death and bacteremia were similar in the two groups. Antibiotic-resistant strains of S. aureus may cause serious infections and significant mortality.

Reconstructive tomography and applications to ultrasonics

Abstract: Computer technology has brought about a revolution in radiology. By combining the computer with X rays it is possible (in principle) to obtain tomographic images of any cross section in the human body. These techniques are now used for medical diagnosis in all the major hospitals of the world. But X rays are not the only kind of radiation for which computer-assisted tomography is feasible. Microwaves, electron beams, ultrasound, fast subatomic particles from accelerators, gamma rays from such sources as positron annihilation, and even magnetic fields can also be used. This paper is mainly concerned with ultrasound. Acoustic energy can often give a view of a cross section not available with X rays or other types of radiation. A mapping of acoustic and elastic discontinuities can be expected to give a basically different pattern than a mapping of X-ray absorption and scattering coefficients. Several methods of ultrasonic tomography are discussed including methods based on geometric optics and a Doppler-oriented approach. A major portion of the paper is concerned with introducing ways to take into account diffraction effects. Because of the wavelength differences, these effects are far more important for ultrasound than for X rays.

A uniform genetic nomenclature for the nematode Caenorhabditis elegans.

Abstract: A uniform system of genetic nomenclature for the nematode Caenorhabditis elegans is described. Convenient ways are specified to designate genes, mutations and strains, and to attempt to avoid name duplications.

Presentation of the steroid psychoses.

Abstract: This study suggests that patients receiving daily doses of 40 mg of prednisone or its equivalent, are at greater risk for developing steroid psychosis. Psychotic reactions were twice as likely to occur during the first 5 days of treatment as subsequently. Premorbid personality, history of previous p

An Alternative Conceptualization of Political Tolerance: Illusory Increases 1950s–1970s

Abstract: This article proposes an alternative conceptualization of political tolerance, a new measurement strategy consistent with that conceptualization, and some new findings based upon this measurement strategy. Briefly put, we argue that tolerance presumes a political objection to a group or to an idea, and if such an objection does not arise, neither does the problem of tolerance. Working from this understanding, we argue that previous efforts to measure tolerance have failed because they have asked respondents about groups preselected by the investigators. Those groups selected as points of reference in measuring tolerance have generally been of a leftist persuasion. Our measurement strategy allowed respondents themselves to select a political group to which they were strongly opposed. They were then asked a series of questions testing the extent to which they were prepared to extend procedural claims to these self-selected targets. Using this approach, we found little change between the 1950s and the 1970s in levels of tolerance in the United States, a result that contradicts much recent research on the problem.

Electrostatic noise at the plasma frequency beyond the earth's bow shock

Abstract: Scarf et al. (1971) and Dunckel (1974) have shown that there are, very frequently, intense electrostatic waves whose frequency is near the plasma frequency upstream of the earth's bow shock and that these waves are correlated with the presence of energetic electrons from the bow shock. Also, Fredericks et al. (1971) have postulated a two-stream instability. The paper investigates these phenomena further, by comparing electrostatic noise at or near the ambient solar wind plasma frequency with times when the interplanetary magnetic field probably connects to the shock. Evidence is presented that Scarf et al. and Fredericks et al. were correct in their explanation of the phenomenon, and that the double-humped distribution would be expected only in a region too small to be resolved by the plasma measurements made so far.

Differential polarized phase fluorometric investigations of diphenylhexatriene in lipid bilayers. Quantitation of hindered depolarizing rotations.

Abstract: Differential polarized phase fluorometry has been used to investigate the depolarizing rotations of 1,6-diphenyl-1,3,5-hexatriene (DPH) in isotropic solvents and in lipid bilayers. For DPH dissolved in isotropic solvents, there is a precise agreement between the observed and predicted values for maximum differential tangents, indicating that in these media DPH is a free isotropic rotator. In lipid bilayers the tangent defects (i.e., the differences between the calculated and the observed maximum differential tangents) are too large to be explained by anisotropy in the depolarizing rotations but are accounted for by hindered isotropic torsional motions for the fluorophore [Weber, G (1978) Acta Phys. Pol A 54, 173]. This theory describes the depolarizing rotations of the fluorophore by its rotational rate R (in radians/second) and the limiting fluorescence anisotropy (r) at times long compared with the fluorescence lifetime. Through the combined use of both steady-state anisotropy measurements and differential phase measurements, we have demonstrated that one may obtain unique solutions for both R and r. For DPH embedded in vesicles prepared from dimyristoyl-, dipalmitoyl-, and distearoylphosphatidylcholines, the depolarizing motions are highly hindered at temperatures below the transition temperature (Tc) but are unhindered above Tc. The apparent rotational rates of the probe do not change significantly at Tc. These data suggest that the changes observed in the steady-state anisotropy near Tc derive primarily from changes in the degree to which the probe's rotations are hindered, and only to a small extent from changes in rotational rate. For DPH embedded in bilayers that contained 25 mol % cholesterol, no clear transition occurred and the rotations appeared to be hindered at all temperatures. The rotational motions of DPH embedded in dioleolyphosphatidylcholine were found to be far less hindered, but the rotational rates were similar to those obtained in the saturated phosphatidylcholines. Finally, the data show that in an anisotropic environment, such as that of a lipid bilayer, steady-state fluorescence anisotropy measurements alone cannot yield quantitatively meaningful rotational rates. Extrapolation of steady-state aniosotropy data to the quantitation of membrane viscosity is therefore difficult, if not invalid; however, qualitative comparisons can be useful.

Outcome Functions Yielding Wairasian and Lindahi Allocations at Nash Equilibrium Points

Abstract: In this paper we shall present " balanced outcome functions " These are functions which, for any given set of messages by individual agents in the economy, determine as their outcome an economic allocation satisfying the resource balance constraints of the economyie the constraints that, for any good, total demand must not exceed total supply Now, it has been known for a long time that outcome functions realizing the Walrasian (or Lindahl) equilibrium correspondence can easily be constructed provided an auctioneer is permitted and balance not required In unpublished work, Schmeidler has presented a balanced outcome function without an auctioneer which realizes the Walrasian correspondence when there are at least three traders; a later variant (in a forthcoming paper by the Author) appears also to work for two traders As he himself noted, his outcome function is not individually feasible It is also discontinuous Groves and Ledyard (1977) proposed balance outcome functions whose equilibrium correspondences yield allocations which are Pareto optimal but not individually rational (in the sense that traders can be worse off than if they refused to trade at all), and hence not Lindahl allocations Here again it is required that there be at least three traders The outcome functions used by Groves and Ledyard are quadratic, and so smooth For the pure exchange economy with at least three traders Hurwicz (1976) has constructed analogous balanced outcome functions which are Pareto optimal but not individually rational, as well as non-balanced outcome functions which are Pareto optimal (but not individually rational) when there are two traders Shapley, Shubik, Schmeidler, Pazner and Postlewaite have also constructed feasible outcome functions that can yield allocations outside the Pareto optimal set Either the outcome functions or the message spaces depend, however, on the initial endowment vectors, so that agents have to know one anothers' endowments Thus, these outcome functions are not informationally decentralized In the present paper we show balanced outcome functions that are smooth and, without employing an auctioneer, yield equivalence between Nash and Walrasian (or, where appropriate, Lindahl) allocations, for three or more traders Our outcome functions are smooth, but not individually feasible away from equilibrium

Thermal fluctuation of fine ferromagnetic particles

Abstract: Fine ferromagnetic particles jump spontaneously from one locally stable state to another; they surmount intervening energy bartiers with the aid of thermal agitation. A theory of this phenomenon has as its primary goal the calculation of time constants. The elements of such a theory are presented. The emphasis is on calculations that require only elementary methods and on results that are simple enough to be easily applicable. The reader is assumed to be acquainted with the basic properties of ferromagnetic materials but not necessarily with Brownian-motion theory, on which the present theory is based.

Ballistic transport in semiconductor at low temperatures for low-power high-speed logic

Abstract: At low temperatures, a mean free path of electrons in semiconductors may exceed device dimensions. Current-voltage characteristics, potentials, electrical field, and carrier distributions are calculated for a two-terminal device under such conditions when the electron transport is ballistic. Current-voltage characteristics of a "ballistic" FET are analyzed using an approach similar to the Shockley model. It is shown that very high drift velocities can be obtained at low voltages leading to high speed and low power consumption in possible applications in logic circuits. For example, GaAs logic devices with characteristic dimensions about a micrometer or less at 77 K will be comparable with or better than Josephson tunneling logic gates.