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Showing papers by "University of Chicago published in 1979"


Journal ArticleDOI
TL;DR: Personality was studied as a conditioner of the effects of stressful life events on illness onset to support the prediction that high stress/low illness executives show, by comparison with high Stress/high illness executives, more hardiness.
Abstract: Personality was studied as a conditioner of the effects of stressful life events on illness onset. Two groups of middle and upper level executives had comparably high degrees of stressful life events in the previous 3 years, as measured by the Holmes and Rahe Schedule of Recent Life Events. One group (n = 86) suffered high stress without falling ill, whereas the other (n = 75) reported becoming sick after their encounter with stressful life events. Illness was measured by the Wyler, Masuda, and Holmes Seriousness of Illness Survey. Discriminant function analysis, run on half of the subjects in each group and cross-validated on the remaining cases, supported the prediction that high stress/low illness executives show, by comparison with high stress/high illness executives, more hardiness, that is, have a stronger commitment to self, an attitude of vigorousness toward the environment, a sense of meaningfulness, and an internal locus of control.

3,598 citations


Book
01 Jan 1979
TL;DR: In this article, a number of alternative measures are considered, almost all based upon a probabilistic model for activity to which the cross-classification may typically lead, and only the case in which the population is completely known is considered, so no question of sampling or measurement error appears.
Abstract: When populations are cross-classified with respect to two or more classifications or polytomies, questions often arise about the degree of association existing between the several polytomies. Most of the traditional measures or indices of association are based upon the standard chi-square statistic or on an assumption of underlying joint normality. In this paper a number of alternative measures are considered, almost all based upon a probabilistic model for activity to which the cross-classification may typically lead. Only the case in which the population is completely known is considered, so no question of sampling or measurement error appears. We hope, however, to publish before long some approximate distributions for sample estimators of the measures we propose, and approximate tests of hypotheses. Our major theme is that the measures of association used by an empirical investigator should not be blindly chosen because of tradition and convention only, although these factors may properly be g...

2,672 citations


Journal ArticleDOI
TL;DR: The decline in synaptic density observed between ages 2--16 years was accompanied by a slight decrease in neuronal density, and human cerebral cortex is one of a number of neuronal systems in which loss of neurons and synapses appears to occur as a late developmental event.

2,413 citations


Journal ArticleDOI
TL;DR: In this article, the second-order Raman spectrum of pyrolytic graphite has been studied and the dependence of the first-order graphite Raman spectra on crystallite size has been shown.
Abstract: First- and second-order Raman scattering from graphite has been studied. The second-order spectra of single crystals and of highly oriented pyrolytic graphite are continuous and exhibit several well-defined bands which can be attributed to features in the density of vibrational states as determined from current lattice-dynamics models. The density of states deduced from the lattice-dynamics model of Nicklow, Wakabayashi, and Smith provides the best replication of the second-order Raman spectrum, but is nevertheless somewhat deficient in this regard, and in need of improvement. The dependence of the first- and second-order graphite Raman spectra on crystallite size has also been studied for a series of samples with typical dimensions ${L}_{c}$ and ${L}_{a}$ as small as 30 \AA{}. With decreasing crystal size the features in the second-order spectrum broaden noticeably and additional broad features appear in both the first- and second-order spectra. The additional first- and second-order features are also attributed to structure in the vibrational density of states and arise from the wave-vector selection-rule relaxation that results from finite-crystal-size effects. Evidence is presented to demonstrate that the above described spectral features are intrinsic and not associated with impurity excitations.

1,907 citations


Journal ArticleDOI
TL;DR: In this paper, a theory of the underlying metastable phase, the amorphous phase, is developed, which is useful for describing the behavior of the viscosity of dense liquids and glasses.
Abstract: The free-volume model, which has been useful for describing the behavior of the viscosity $\ensuremath{\eta}$ of dense liquids and glasses, is extended to account for their thermodynamic behavior as well. Experimental results for the heat capacity ${C}_{p}$ and the volume $\overline{v}$ show that the system falls out of complete, metastable thermodynamic equilibrium at the glass transition temperature ${T}_{g}$. As a first step in understanding these universal phenomena, a theory of the underlying metastable phase, the amorphous phase, is developed. Recent molecular-dynamic calculations demonstrating the existence of a cellular structure in liquids and the properties of the local free energy of the molecular cells permit us to formulate more precisely and justify in more detail the standard free-volume model. In particular, it is possible to define the free volume and distinguish solid-like and liquidlike cells. This leads to the introduction of percolation theory, which is used to describe the gradual development of the communal entropy of the amorphous phase. We then determine the probability distribution of the cellular volume as a function of the fraction of liquidlike cells, $p$. The equilibrium liquid-glass transition is associated with the increase of $p$ with temperature. This occurs via a phase transition which is most probably first order. The results of our theory give a generalized equation for the viscosity which agrees accurately with experimental results at all temperatures. Results for ${C}_{p}$ and $\overline{v}$ are also obtained. This equilibrium theory can provide the basis for a relaxation theory of the kinetic effects observed around and below ${T}_{g}$. The relationship between the entropy theory and the free-volume model is also clarified.

1,000 citations


Posted Content
TL;DR: The authors analyzes compensation schemes which pay according to an individual's ordinal rank in an organization rather than his output level and shows that wages based upon rank induce the same efficient allocation of resources as an incentive reward scheme based on individual output levels.
Abstract: This paper analyzes compensation schemes which pay according to an individual's ordinal rank in an organization rather than his output level. When workers are risk neutral, it is shown that wages based upon rank induce the same efficient allocation of resources as an incentive reward scheme based on individual output levels. Under some circumstances, risk-averse workers actually prefer to be paid on the basis of rank. In addition, if workers are heterogeneous inability, low-quality workers attempt to contaminate high-quality firms, resulting in adverse selection. However, if ability is known in advance, a competitive handicapping structure exists which allows all workers to compete efficiently in the same organization.

890 citations


Journal ArticleDOI
TL;DR: In this article, the correlations of Hottel, Whillier, Liu and Jordan between diffuse and hemispherical, and between instantaneous (hourly) values and daily totals of solar radiation are recalibrated against pyrheliometer data for five stations in the U.S.

865 citations


Journal ArticleDOI
TL;DR: In this paper, a class of models for the analysis of association in a contingency table with ordered rows and ordered columns is proposed, including the null association model, the uniform association model and models that describe the possible effects of the rows and columns on the association.
Abstract: A class of models is proposed for the analysis of association in a contingency table with ordered rows and ordered columns. Association is measured in terms of the odds-ratios in 2 × 2 subtables formed from adjacent rows and adjacent columns. This class includes the null association model, the uniform association model, and models that describe the possible effects of the rows and/or columns on the association. With these models, the association in the table can be analyzed in a manner analogous to the usual two-way analysis of variance, and parsimonious descriptions of this association can be obtained often. Applications are discussed here, some well-known sets of data are reanalyzed, and new insights into these data are obtained.

830 citations


Journal ArticleDOI
TL;DR: Oxygen isotopic fractionations have been determined between quartz and water, albite and water and anorthite and water at temperatures from 300 to 825°C, and pressures from 15 to 25 kbar as mentioned in this paper.

781 citations


Journal ArticleDOI
TL;DR: Data on the threshold visibility of spatially localized, aperiodic patterns are used to derive the properties of a general model for threshold spatial vision that quantitatively predicts the spatial modulation transfer function (cosine grating thresholds) under both sustained and transient conditions with no free parameters.

741 citations


Journal ArticleDOI
TL;DR: In this article, a multilocation newsboy problem with normal demand at each location and identical linear holding and penalty cost functions is considered, and an expression is derived for the resulting expected holding and penalties as a function of the demand parameters for each location means, variances, and correlation coefficients.
Abstract: This paper concerns a multilocation newsboy problem with normal demand at each location and identical linear holding and penalty cost functions at each location. Consolidation of demand from several facilities is considered, and an expression is derived for the resulting expected holding and penalty costs as a function of the demand parameters for each location means, variances, and correlation coefficients. The expression is used to demonstrate that i the expected holding and penalty costs in a decentralized system exceed those in a centralized system; ii the magnitude of the saving depends on the correlation of demands; and iii if demands are identical and uncorrelated, the costs increase as the square root of the number of consolidated demands.

Journal ArticleDOI
TL;DR: A stage theory of adult life seems oversimplified because the timing of life events is becoming less regular, age is losing its customary social meanings, and the trends are toward the fluid life cycle and an age-irrelevant society.
Abstract: Psychologists are increasingly interested in the life cycle as the unit for study and in such questions as whether adult development, like child development, is to be perceived as a succession of stages. A stage theory of adult life seems oversimplified for several reasons. First, the timing of life events is becoming less regular, age is losing its customary social meanings, and the trends are toward the fluid life cycle and an age-irrelevant society. Second, the psychological themes and preoccupations reported by young, middle-aged, and older persons are recurrent ones that appear and reappear in new forms and do not follow in a single fixed order. Third, intrapsychic changes occur slowly with age and not in stepwise fashion. These factors may have implications for the psychiatrist who, in helping the patient make a meaningful life story from a life history, deals always with issues of time, timing, and aging.


Journal ArticleDOI
TL;DR: Bifurcation theory and group theory are used to demonstrate the existence of a variety of doublyperiodic patterns, hexagons, rolls, etc., as solutions to the field equations for the net activity.
Abstract: Neuronal activity in a two-dimensional net is analyzed in the neighborhood of an instability. Bifurcation theory and group theory are used to demonstrate the existence of a variety of doublyperiodic patterns, hexagons, rolls, etc., as solutions to the field equations for the net activity. It is suggested that these simple geometric patterns are the cortical concomitants of the "form constants" seen during visual hallucinosis.

Journal ArticleDOI
TL;DR: In this article, a non-recursive simultaneous equation model was proposed for the 1972 and 1976 elections using CPS data, and the results showed that policy preferences appear to have much more influence on voting decisions and party attachments much less, than was previously thought.
Abstract: Past studies have offered diverse estimates of the role of policy preferences, party loyalties, candidate personalities and other factors in voting decisions. Most have postulated recursive (that is, one-way) causal relationships among the central variables. This study specifies a non-recursive simultaneous equation model and estimates its parameters for the 1972 and 1976 elections using CPS data. The estimates differ markedly from those of simple recursive models. Policy preferences appear to have much more influence on voting decisions, and party attachments much less, than was previously thought. Candidate evaluations strongly affect voters' perceptions of closeness to candidates on policy issues. Party identification may be influenced by short-term factors. Differences between 1972 and 1976 reflect the issue-oriented McGovern candidacy. Simultaneous equation models offer no cure-all; in the absence of accepted theory many specifications are open to controversy. But future research must take account of reciprocal causal paths.


Journal ArticleDOI
TL;DR: None of the Diekmann's lying-in study group has had carcinoma to date, but one must keep in mind the reported increased risk of testicular carcinoma in testes that are or were cryptorchid.


Journal ArticleDOI
TL;DR: The chemical composition of Mars is estimated from the cosmochemical model of Ganapathy and Anders (1974) with additional petrological and geophysical constraints as mentioned in this paper, and it is noted that the mantle is an iron-rich garnet wehrlite, nearly identical to the bulk moon composition of Morgan at al. (1978) and that the core is sulfur poor (3.5% S).

Journal ArticleDOI
TL;DR: Temperature-sensitive nalA mutants of Escherichia coli have been used to investigate the structure and functions of deoxyribonucleic acid (DNA) gyrase, proving definitively that n alA is the structural gene for subunit A and the nalidixic acid target are one and the same protein.
Abstract: Temperature-sensitive nalA mutants of Escherichia coli have been used to investigate the structure and functions of deoxyribonucleic acid (DNA) gyrase. Extracts of one such mutant (nalA43) had thermosensitive DNA gyrase subunit A activity but normal gyrase subunit B activity, proving definitively that nalA is the structural gene for subunit A. Extracts of a second nalA (Ts) mutant (nalA45) had a 50-fold deficiency of gyrase subunit A activity. The residual DNA supertwisting was catalyzed by the mutant DNA gyrase rather than by a novel supertwisting enzyme. The nalA45(Ts) extract was also deficient in the nalidixic acid target, which is defined as the protein necessary to confer drug sensitivity to in vitro DNA replication directed by a nalidixic acid-resistant mutant extract. Thus, gyrase subunit A and the nalidixic acid target are one and the same protein, the nalA gene product. Shift of the nalA43(Ts) mutant to a nonpermissive temperature resulted in a precipitous decline in the rate of [(3)H]thymidine incorporation, demonstrating an obligatory role of the nalA gene product in DNA replication. The rates of incorporation of [(3)H]uridine pulses and continuously administered [(3)H]uracil were quickly reduced approximately twofold upon temperature shift of the nalA43(Ts) mutant, and therefore some but not all transcription requires the nalA gene product. The thermosensitive growth of bacteriophages phiX174 and T4 in the nalA43(Ts) host shows that these phages depend on the host nalA gene product. In contrast, the growth of phage T7 was strongly inhibited by nalidixic acid but essentially unaffected by the nalA43(Ts) mutation. The inhibition of T7 growth by nalidixic acid was, however, eliminated by temperature inactivation of the nal43 gene product. Therefore, nalidixic acid may block T7 growth by a corruption rather than a simple elimination of the nalidixic acid target. Possible mechanisms for such a corruption are considered, and their relevance to the puzzling dominance of drug sensitivity is discussed.


Journal ArticleDOI
TL;DR: Three mutations at different loci (syn loci) which alter the social behavior of infected cells from clumping of rounded cells to polykaryocytosis, and a mutation which determines the accumulation of one major glycoprotein are mapped.
Abstract: We have mapped the location in herpes simplex virus (HSV) DNA of (i) three mutations at different loci ( syn loci) which alter the social behavior of infected cells from clumping of rounded cells to polykaryocytosis, (ii) a mutation which determines the accumulation of one major glycoprotein [VP8.0(C 2 )], and (iii) the sequences encoding four major virus glycoproteins [VP8.0(C 2 ), VP7(B 2 ), VP8.5(A), and VP19E(D 2 )]. The experimental design and results were as follows. (i) Analysis of HSV-1 × HSV-2 recombinants showed that the sequences encoding the VP19E(D 2 ) glycoprotein map in the S component, whereas the sequences encoding the other three major glycoproteins are in two locations in the L component of HSV DNA. The templates specifying the HSV-1 and HSV-2 glycoprotein VP8.0(C 2 ) appear not to be colinear; we isolated recombinants specifying glycoproteins comigrating in sodium dodecyl sulfate-polyacrylamide gels with VP8.0(C 2 ) of both HSV-1 and HSV-2. (ii) Marker rescue of a ts mutant defective in accumulation of glycoprotein VP7(B 2 ) showed that the mutation maps within a region containing the sequences encoding that glycoprotein. (iii) Marker transfer experiments involving transfection of rabbit skin cells with donor HSV-1(F) DNA and fragments from several donor strains causing fusion of Vero or both Vero and HEp-2 cells revealed the existence of three syn loci specifying the social behavior of cells and one locus ( Cr ) determining the accumulation of glycoprotein VP8.0(C 2 ). The Cr locus maps to the right of the template specifying VP8.0(C 2 ) glycoprotein. Loci syn 1 and syn 2 map at or near the Cr locus but can be segregated from it. Locus syn 3 maps at or near the template specifying glycoproteins VP7(B 2 ) and VP8.5(A). The expression of mutations in the syn 1 and syn 3 loci appear to be cell type dependent, in that recombinants with these mutations fuse Vero cells but not HEp-2 cells. Recipients of the syn 2 locus or of both syn 2 and syn 1 loci fuse both Vero and HEp-2 cells. Images

Journal ArticleDOI
TL;DR: It is demonstrated that substance P and [Met5]-enkephalin-positive reactions are selectively localized to subcellular organelles in axon terminals in the locus coeruleus and A2 region of rat brain.


Journal ArticleDOI
TL;DR: In this paper, the authors discuss the conditions under which conventional tools, such as financial ratios and measures of industry central tendency, achieve the intended objectives of analysis (e.g., size control).

Journal ArticleDOI
TL;DR: In this paper, the path-dependent phase factor P exp(i∫σAμdzμ) in gauge theory is studied and it is shown that it satisfies differential equations which are equivalent to those for a quantized string if the gauge fields meet certain constraints.

Journal ArticleDOI
TL;DR: This paper explored the role of climate amenities in net migration behavior over the life-cycle, by race, and found that holding constant climate is seen to greatly improve the performance of traditional economic variables.

Journal ArticleDOI
TL;DR: The program described here is an implementation of the generator described by Lewis et al. and indirectly attributed to D.H. Lehmer, and produces a sequence of positive integers, IX, by the recursion.
Abstract: There are a number of situations in which it is desirable to have a random number generator that is machine independent. In general, it is useful if a program written in a high-level language produces results which are the same from machine to machine as long as the input to the program is the same. For example, the pseudorandom number generator used by the Control Data Corporation in its GPSS simulation program is the same as in IBM's GPSS, even though the generator is known to have defective statistical behavior. Apparently, compatibility is more valuable than statistical goodness. The program described here is an implementation of the generator described by Lewis et al. [6] and indirectly attributed to D.H. Lehmer. The code for the program appears in Figure 1. The generator produces a sequence of positive integers, IX, by the recursion:

Journal ArticleDOI
TL;DR: Concanavalin A (Con A)–activated suppressor cell activity was determined in multiple sclerosis patients who had been assigned to one of three subgroups, those with active disease, those recovering from a flare‐up, and those with stable disease.
Abstract: Concanavalin A (Con A)-activated suppressor cell activity was determined in multiple sclerosis (MS) patients who had been assigned to one of three subgroups, those with active disease, those recovering from a flare-up, and those with stable disease. The level of suppression induced by the Con A-activated suppressor cells on the mitogenic response of autologous peripheral blood lymphocytes was reduced in patients with active disease (3 +/- 8%) compared with stable patients (30 +/- 8%), patients recovering from a flare-up (62 +/- 5%), and controls (40 +/- 5%). As a measure of the actual amounts of suppressor factors released, the effect of supernatants from the Con A-activated cells on the proliferative activity of a dividing cell line (L cells) was determined concurrently. The inhibitory effect of supernatants from activated cells was reduced in active and stable MS patients (7 +/- 3%) compared to controls (21 +/- 4%). Three of 4 with active MS showed mildly elevated immune complex levels as measured by the Raji cell technique; each of these patients had low suppressor activity. Levamisole (1 microgram per milliliter) failed to alter suppressor cell activity in our in vitro system.

Journal ArticleDOI
TL;DR: In this article, the invariant cross-sections of hadrons at large transverse momentum were measured at a laboratory angle of 77 mrad, which corresponds to angles near 90\ifmmode^\circ\else\textdegree\fi{} in the c.m. system of the incident proton and a single nucleon at rest.
Abstract: Measurements of the invariant cross section $\frac{E{d}^{3}\ensuremath{\sigma}}{{d}^{3}p}$ are presented for the production of hadrons ($\ensuremath{\pi}$, $K$, $p$, and $\overline{p}$) at large transverse momentum (${p}_{\ensuremath{\perp}}$) by 200-, 300-, and 400-GeV protons incident on ${\mathrm{H}}_{2}$, ${\mathrm{D}}_{2}$, Be, Ti, and W targets. The measurements were made at a laboratory angle of 77 mrad, which corresponds to angles near 90\ifmmode^\circ\else\textdegree\fi{} in the c.m. system of the incident proton and a single nucleon at rest. The range in ${p}_{\ensuremath{\perp}}$ for the data is $0.77\ensuremath{\le}{p}_{\ensuremath{\perp}}\ensuremath{\le}6.91$ GeV/c, corresponding to values of the scaling variable ${x}_{\ensuremath{\perp}}=\frac{2{p}_{\ensuremath{\perp}}}{\sqrt{s}}$ from 0.06 to 0.64. For $p\ensuremath{-}p$ collisions, the pion cross sections can be represented in the region ${x}_{\ensuremath{\perp}}g35$ by the form $(\frac{1}{{{p}_{\ensuremath{\perp}}}^{n}}){(1\ensuremath{-}{x}_{\ensuremath{\perp}})}^{b}$, with $n=8$ and $b=9$. The ratio of ${\ensuremath{\pi}}^{+}$ to ${\ensuremath{\pi}}^{\ensuremath{-}}$ production grows as a function of ${x}_{\ensuremath{\perp}}$ to a value larger than 2 at ${x}_{\ensuremath{\perp}}\ensuremath{\gtrsim}0.5$. The ratios of the production of ${K}^{+}$ and protons to ${\ensuremath{\pi}}^{+}$ and of ${K}^{\ensuremath{-}}$ and antiprotons to ${\ensuremath{\pi}}^{\ensuremath{-}}$ also scale with ${x}_{\ensuremath{\perp}}$ for $p\ensuremath{-}p$ collisions. The ${K}^{\ifmmode\pm\else\textpm\fi{}}$, $p$, and $\overline{p}$ fitted values for $n$ and $b$ are given. Particle ratios are also presented for ${\mathrm{D}}_{2}$, Be, Ti, and W targets and the dependences on atomic weight ($A$) are discussed.