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Showing papers by "Johns Hopkins University published in 1969"


Journal ArticleDOI
TL;DR: This paper discusses the development of a 64-item self-report measure of empathy, constructed by comparing the responses of groups with high- and low-rated empathy, using the combined MMPI-CPI item pool.
Abstract: The concept of empathy—the intellectual or imaginative apprehension of another's condition or state of mind— is central for understanding a broad range of social phenomena including, in particular, moral development. Within this latter context, an empathic disposition can be regarded as the capacity to adopt a broad moral perspective, that is, to take "the moral point of view." This paper discusses the development of a 64-item self-report measure of empathy, constructed by comparing the responses of groups with high- and low-rated empathy, using the combined MMPI-CPI item pool. After providing evidence concerning the scale's reliability and validity, an attempt is made to show its relevance for specifically moral conduct by relating empathy scale scores to real life indexes of socially appropriate behavior and to certain previously wellvalidated measures of personality. Some form of empathic disposition, roletaking ability, or social sensitivity is assumed by all approaches to personality which take the interpersonal situation as a major focus of concern. Accordingly, most writers in the role-theoretical tradition (Cottrell, 1942; Gough, 1948; Mead, 1934; Sarbin, 1968) have given careful attention to this aspect of social functioning. Mead, for example, has argued that role-taking ability is the key variable in social and moral development; extending this line of reasoning he equates the "g" factor in intelligence with social sensitivity, the origins of which can be found in the central nervous system. In a similar vein, Cottrell and Dymond (1949) also maintained that empathy is the basic process in all social interaction. Empathy, seen as an everyday manifestation of the disposition to adopt a broad moral

1,368 citations


Journal ArticleDOI
TL;DR: The intracellularly recorded response characteristics of each type of neuron in a vertebrate retina are described, and the response of each neuron to the responses of those neurons to which it is synaptically coupled are related.
Abstract: the optic nerve, it has been possible to specify many of the functions performed bv the vertebrate retina. These include brightness detection (16, 18, 27), centersurround contrast detection (1, 8, 20, 23), and motion detection (3, 4, 26-28). It has not been possible, however, to determine how the retina organizes the visual message recorded at the optic nerve, primarily because intracellular recording from single cells distal to the ganglion cells has been difficult. Detailed structural studies of the vertebrate retina, such as the one in the preceding paper (14), provide a framework within which the functional organization of the retina can be described. The anatomical studies show a limited number of clearly defined synaptic structures at which interaction between specific neurons can take place. In this paper we shall describe the intracellularly recorded response characteristics of each type of neuron in a vertebrate retina, and then relate the response of each neuron to the responses of those neurons to which it is synaptically coupled. By following the responses through the synaptic pathways, we can begin to describe how information from the visual field is abstracted and encoded in the retina. Intracellular recording throughout most retinas has been difficult because even the finest available micropipettes fail to penetrate the small retinal neurons consistently without damage. Bortoff (5-7) showed that this difficulty could be overcome by recording in an animal with larger retinal neurons: the mudpuppy, Nectwus maculosus. As described in the preceding paper (14),

1,356 citations



Journal ArticleDOI
TL;DR: In this paper, a simple LSD (least significant difference) rule is presented for simultaneously testing the differences between n treatments considered in all possible pairs, which is based on the same multiple decision theory model except for a modified and extended use of a conjugate chi-square density in the prior.
Abstract: A simple LSD (least significant difference) rule is presented for simultaneously testing the differences between n treatments considered in all possible pairs. This rule is a simpler, fully completed, version of the Bayes rule presented for special cases in Duncan [4]. It is based on the same multiple decision theory model except for a modified and extended use of a conjugate chi-square density in the prior. The new rule has the same intuitively appealing dependence on the between-treatment F ratio, varying from a sensitive comparisonwise-α-like rule when F is large or moderate, to a conservative experimentwise-α-like rule when F is small. Tables of t for computing the LSD are presented for three choices of a type-1 to type-2 error-seriousness ratio, k = 50, 100 and 500 (analogous to the usual choices of α = .10, .05 and .01 in testing a single difference), and for full ranges of F and its degree of freedom q and f.

820 citations


Journal ArticleDOI
TL;DR: The structure of the human, but mainly of the rhesus monkey, retina as examined by Golgi-staining techniques is described and interpreted on evidence from both light and electron microscopy.
Abstract: The structure of the human, but mainly of the rhesus monkey, retina as examined by Golgi-staining techniques is described and interpreted on evidence from both light and electron microscopy. One type of rod bipolar cell and two types of cone bipolar cell are recognized. The rod bipolar is exclusively connected to rods. The midget bipolar is postsynaptic to only one cone but each cone is also presynaptic to a diffuse cone (flat) bipolar. Such flat bipolar cells are in synaptic relationship with about seven cones. No other bipolar cell types have been found. The brush bipolar of Polyak is interpreted as probably a distorted rod bipolar, while Polyak's centrifugal bipolar is a misinterpretation of the morphology of diffuse amacrine cells. When presumptive centrifugal bipolars were observed they appeared to be a developmental stage of amacrine cells. In the outer plexiform layer two types of horizontal cell have been defined. Each type of horizontal cell has a single axon and two kinds of horizontal cell axon terminals are recognized. In the inner plexiform layer there are two main classes of amacrine cells: the stratified amacrines and the diffuse amacrines. Each class of amacrine has a wide variety of shapes. Polyak's midget ganglion cell is confirmed and his five other kinds of ganglion cell are classified into diffuse and stratified ganglion cells according to the level at which their dendrites branch within the inner plexiform layer. A fuller summary is given by the diagram and in the legend of figure 98, p. 174. A new type of midget bipolar is described in the Appendix (p. 177).

552 citations


Journal ArticleDOI
TL;DR: In this article, a constant stress is applied to the surface of an initially quiescent tank of fluid with a uniform density gradient, and the development of the turbulent layer by entrainment of the underlying fluid is described.
Abstract: An experiment is described in which a constant stress is applied to the surface of an initially quiescent tank of fluid with a uniform density gradient. The development of the turbulent layer by entrainment of the underlying fluid is described and it is found that the entrainment coefficient E, the ratio of the entrainment velocity ue to the friction velocity u* is given in terms of the depth D of the mixed layer and the density jump δρ across the entrainment interface by the relation \[ E = \frac{u_e}{U_{*}} = 2.5\frac{\rho_0u^2_{*}}{g\delta\rho D}. \] The rate of increase of potential energy of the stratified fluid was found to be proportional to the rate of dissipation of kinetic energy per unit area in the turbulent layer. The form of these results is consistent with those found by Turner with an agitation tank, but the parameters used here allow direct application to entrainment in the ocean.

479 citations



Journal ArticleDOI
TL;DR: The components and properties of a phosphoenolpyruvate: glucose phosphotransferase system are reviewed, along with the evidence implicating this system in sugar transport across bacterial membranes.
Abstract: The components and properties of a phosphoenolpyruvate: glucose phosphotransferase system are reviewed, along with the evidence implicating this system in sugar transport across bacterial membranes. Some possible physiological implications of sugar transport mediated by the phosphotransferase system are also considered.

294 citations


Journal ArticleDOI
TL;DR: In this article, the semantic field of animal terms in English was investigated with five experimental techniques: free listing, pair ratings, triad ratings, verbal associations, and paired-associates learning.

265 citations


Journal ArticleDOI
TL;DR: Comparison of theoretical results and experimental values for transmittance through rabbit cornea shows that the quasi-regular quasi-random structure revealed by the electron microscope is not in conflict with transparency.
Abstract: The physical basis for the transparency of the cornea to visible light is investigated theoretically in terms of the molecular structure as depicted by electron microscopy. Electron micrographs show that the major portion of the cornea contains long cylindrical fibrils arranged in a quasi-random fashion, with local order extending over distances comparable to the wavelength of light. Heretofore, the generally accepted explanation of transparency has been in terms of a supposed crystalline arrangement of the fibrils, because this was the only distribution that could ensure transparency on a simple theoretical basis. Thus, the non-crystalline structure shown by the electron microscope has been widely regarded as an artifact due to the fixation procedure. In the present work, the light scattering from the fibrils is formulated in terms of their radial distribution function, which is determined by numerical analysis of electron micrographs. Comparison of theoretical results and experimental values for transmittance through rabbit cornea shows that the quasi-regular quasi-random structure revealed by the electron microscope is not in conflict with transparency.

254 citations


Journal ArticleDOI
TL;DR: All enzymatic activities associated with nitrate reductase are heat-labile but to varying degrees, with the NADPH-nitrate and -cytochrome c reductases being most sensitive, and FADH2- and reduced methyl viologen-nitrates reduct enzyme activities being progressively less so, in that order.

Journal ArticleDOI
TL;DR: The possible function of the protein-bound RNA in chick embryo chromatin is examined by experiments involving chromatin reconstitution and DNA-RNA hybridization of the template products.

Journal ArticleDOI
TL;DR: Weingartner et al. as discussed by the authors developed a dynamic programming algorithm for optimal capital allocation subject to budget constraints, including multilevel projects, reinvesting returns, borrowing and lending, capital deferrals, and project interactions.
Abstract: Dynamic programming algorithms are developed for optimal capital allocation subject to budget constraints. We extend the work of Weingartner [Weingartner, H. M. 1966. Capital budgeting of interrelated projects: Survey and synthesis. Management Sci.127, March 485--516.] and Weingartner and Ness [Weingartner, H. M., D. N. Ness. 1967. Methods for the solution of the multi-dimensional 0/1 knapsack problem. Oper. Res.151, January--February 83--108.] by including multilevel projects, reinvesting returns, borrowing and lending, capital deferrals, and project interactions. We are able to handle dynamic programming models with several state variables because the optimal returns are monotone non-decreasing step functions. Computational experience with a variety of problems is reported.

Journal ArticleDOI
TL;DR: In this paper, α-amylase from Aspergillus oryzae was purified by gel filtration and ion-exchange chromatography, and showed that the mixture contained glucosamine, mannose, galactose, arabinose, and xylose.

Journal ArticleDOI
TL;DR: The synaptic contacts made by carp retinal neurons were studied with electron microscopic techniques and Serial synapses between amacrine processes and reciprocal synapsesbetween amacine processes and bipolar terminals are described.
Abstract: The synaptic contacts made by carp retinal neurons were studied with electron microscopic techniques. Three kinds of contacts are described: (1) a conventional synapse in which an accumulation of agranular vesicles is found on the presynaptic side along with membrane densification of both pre- and postsynaptic elements; (2) a ribbon synapse in which a presynaptic ribbon surrounded by a halo of agranular vesicles faces two postsynaptic elements; and (3) close apposition of plasma membranes without any vesicle accumulation or membrane densification.

Journal ArticleDOI
TL;DR: This paper gives an enumerative algorithm for the set-partitioning problem, that is, theset-covering problem with equality constraints, and presents computational results for real and randomly generated problems.
Abstract: This paper gives an enumerative algorithm for the set-partitioning problem, that is, the set-covering problem with equality constraints, and presents computational results for real and randomly generated problems. The fact that many problems can be solved more rapidly than the corresponding linear programs demonstrates the efficiency of the algorithm; for example, a randomly generated problem with 1,400 variables and 100 constraints was solved in 15 minutes.

Journal ArticleDOI
TL;DR: In this paper, the formation of bedded chert in the High Magadi beds has been investigated and it has been shown that the cherts of the “Chert Series” are stratigraphically equivalent to the magadiite horizons.
Abstract: The High Magadi beds can be divided into a lower and an upper sequence, separated by a bed rich in Tilapia nilotica remains. The lower sequence contains one or more magadiite horizons. Through digging of trenches it has been possible to establish that the cherts of the “Chert Series” are stratigraphically equivalent to the magadiite horizons. The transition magadiite-chert has been observed in many places and may occur over a distance of less than 50 cm. It is accomplished by removal of sodium by percolating waters. The resulting bedded chert may preserve the fine lamination present in magadiite. The conversion is accompanied by many textural and structural features such as large desiccation polygons, buckling, reticulation, extrusion, casts of mud-cracks and calcite. The precipitation of magadiite is postulated to have taken place in annual increments in a stratified lake at the brine-epilimnion interface. The maximum duration is estimated at 4,000–6,000 years. Solubility measurements indicate that most Magadi waters at the present time are supersaturated with respect to magadiite and kenyaite, though no precipitation has been observed. The presence of chert chips in intraformational gravels indicates that the conversion to chert was already initiated during the magadiite precipitation interval. The inorganic mechanism for the formation of bedded chert observed at Magadi is suggested to apply also to the Dales Gorge Member of the Precambrian Brockman Iron Formation of W. Australia. Evidence for magadiite as chert precursor is found in the depositional rates, the presence of riebeckite and in textures such as macules and cross-pods. The proposed model is extended to include Precambrian banded iron formations in general and the restriction of these formations to the early history of the earth is explained by the likely compositions of waters from closed basins.

Journal ArticleDOI
TL;DR: In this paper, the authors checked the two-dimensionalality of the flow by measuring mean velocity and turbulence level profiles at different spanwise positions, and the flow was found uniform over 75% of the span (wind-tunnel width) at the trailing edge at the last downstream station, where wake measurements were taken.
Abstract: First the two-dimensionality of the flow was checked by measuring mean velocity and turbulence level profiles at different spanwise positions, and the flow was found uniform over 75% of the span (wind-tunnel width) at the trailing edge and over 60% of the span at the last downstream station, x = 240 cm, where wake measurements were taken. No detectable periodic components were found in the wake at any downstream station as evidenced either by wave analyzer or by correlation measurements taken with two probes located symmetrically to the centerline and placed near the location of maximum shear stress in the wake. The characteristics of the turbulent boundary layer at the trailing edge (x = 0) were the following: conventional thickness (U/Um = 0.99) d = 5.50 cm, momentum thickness d = 0.58 cm, and shape parameter H = 5*/6 = 1.44. At the same location, the friction velocity was found to be u*/Um = 0.046. This value was obtained by using Clauser's logarithmic law.5 The wall slope method using hot-wire measurements with correction for proximity of the boundary due to Wills 4 yielded a value of u*/Ua = 0.037. The thickness of the trailing edge expressed nondimensionally was quite small, u*h/v = 3; in other words, much smaller than the viscous sublayer. All data is presented in dimensionless form using 00, the momentum thickness at the trailing edge and the undisturbed flow velocity Um as reference quantities. Symmetry of the wake was found to be excellent and representative

Journal ArticleDOI
TL;DR: In this article, the stability of almost fully developed viscous flow in a rotating pipe is considered and it is shown that the flow is unstable for Reynolds numbers R = Wor0/v greater than Rc [asymp ] 82[sdot ]9.
Abstract: The stability of almost fully developed viscous flow in a rotating pipe is considered. In cylindrical polar co-ordinates (r, o, z) this flow has the velocity components \[ \{W_0o(1),\quad\Omega r[1+o(\epsilon)],\quad W_0[1-r^2/r^2_0+o(1)]\},_{+}^{+} \] where e = Wo/2Ωr0 and is bounded externally by the rigid cylinder r = r0, which rotates about its axis with angular velocity Ω. In the limit of small e, the disturbance equations can be solved in terms of Bessel functions and it is shown that, in that limit, the flow is unstable for Reynolds numbers R = Wor0/v greater than Rc [asymp ] 82[sdot ]9. The unstable disturbances take the form of growing spiral waves, which are stationary relative to the rotating cylinder and the critical disturbance at R = Rc has azimuthal wave-number 1 and axial wavelength 2πr0/e. Furthermore, it is shown that the most rapidly growing disturbance for R > Rc has an azimuthal wave-number which increases with R. Some of the problems involved in testing the results by experiment are discussed and a possible application to the theory of vortex breakdown is mentioned. In an appendix this instability is shown to be an example of inertial instability.

Journal ArticleDOI
TL;DR: An important part of the medical care of many chronically-ill patients is self-administration of oral medications at home over a long period of time.
Abstract: AN IMPORTANT PART of the medical care of many chronically-ill patients is self-administration of oral medications at home over a long period of time. Many improvements in the care available for such patients rest in the development of new pharmacologic agents more effective and less toxic than their predecessors. As each new agent is developed, however, it must be submitted to clinical trials comparing it in effectiveness and toxicity with other drugs already in use. Such trials comparing several drugs presume that the patients assigned to receive the drugs being tested actually take their medications as prescribed. It is known, however, that patients vary

Journal ArticleDOI
TL;DR: Three morphologic variations were seen: large destructive, punctate inner retinal, and punctate deep with subretinal fluid at the macula, which had different prognoses for vision, episode duration, and complications.
Abstract: Toxoplasmic retinochoroiditis in 63 referred patients first occurred between ages 7 and 57 with a mean age of 25 years. Each patient had an average of 2.7 episodes, with a range of 1 to 13. The episodes averaged 4.2 months, ranging from one week to two years. Three morphologic variations were seen: large destructive, punctate inner retinal, and punctate deep with subretinal fluid at the macula. These types had different prognoses for vision, episode duration, and complications. Recognition of variations is essential for design of therapeutic trials.

Journal ArticleDOI
TL;DR: The chemical steps and the products of the bioluminescence and chemiluminescent oxidations of firefly luciferin are elucidated and a regulatory mechanism involving dehydro‐luciferin is proposed for control of fireflies flashing.
Abstract: — The chemical steps and the products of the bioluminescent and chemiluminescent oxidations of firefly luciferin are elucidated. The colors of firefly bioluminescence can be explained in terms of different ionic excited states and spectral shifts due to changes in molecular environment. Firefly luciferase undergoes conformational changes during catalysis. There are two sites for light production per 100,000 mW. A regulatory mechanism involving dehydro-luciferin is proposed for control of firefly flashing.

Journal ArticleDOI
TL;DR: Distribution of enzymes and balance studies of malate utilization by Ascaris mitochondria suggest that cytoplasmic malate enters the mitochondrion, whereupon half is oxidized via the malic enzyme to pyruvate and acetate, while the remainder is reduced to succinate and propionate with the generation of ATP.

Journal ArticleDOI
TL;DR: In this paper, the authors considered the traction boundary value problem in the general case where O(U,, ti) may be nonlinear in both u,, zi,.



Journal ArticleDOI
TL;DR: Comparison of the binding energies of several heterocyclic compounds structurally related to benzothiazole suggests that the nitrogen atom of the benzothsiazole ring may be important in orienting the compound to a fixed position in the luciferinbinding site.

Journal ArticleDOI
TL;DR: The radiation of the resonant, fractional-turn, quadrafilar helix is shown to be cardioid shaped and circularly polarized regardless of axial length and diameter.
Abstract: The radiation of the resonant, fractional-turn, quadrafilar helix is shown to be cardioid shaped and circularly polarized regardless of axial length and diameter. Measured and calculated data relate the radiation pattern characteristics and geometrical parameters.

Journal ArticleDOI
05 Sep 1969-Science
TL;DR: Emission features from ionized carbon dioxide and carbon monoxide were measured and the Lyman alpha 1216-angstrom line of atomic hydrogen and the 1304-, 1356-, and 2972-angston lines of atomic oxygen were observed.
Abstract: Emission features from ionized carbon dioxide and carbon monoxide were measured in the 1900- to 4300-angstrom spectral region. The Lyman alpha 1216-angstrom line of atomic hydrogen and the 1304-, 1356-, and 2972-angstrom lines of atomic oxygen were observed.

Journal ArticleDOI
TL;DR: In this article, the variational method is applied to weak second-order resonant interactions among waves whose amplitudes and phase angles vary slowly with position and time, leading to the proof of local conservation of total mean wave energy and momentum laws.
Abstract: Whitham’s variational method is formulated so as to apply to weak second-order resonant interactions among waves whose amplitudes and phase angles vary slowly with position and time. The method is applied in detail to capillary-gravity wave interactions. An internal gravity waves problem is also discussed briefly. The method leads to new and substantial simplifications of the interaction equations. This makes possible the proof of local conservation of total mean wave energy and momentum laws. These, together with another integral of the motion, are found to be of central importance in classifying and characterizing the slow modulations of planewave-like form. Such a classification is given in detail for all initial values of phase angles and relative amplitudes. All progressive uniform waves in the capillary range are found to be unstable with perturbation growth rates which can be of first order in the wave slopes. In this formulation amplitude dependent first-order corrections of classical frequency and/or wave-number arise for all waves participating in a resonance. A few predictions which could be verified by simple experiments are made.