Showing papers by "University of Iowa published in 1972"
TL;DR: In this article, the credibility of the rationales and procedural descriptions of two therapy, three placebo, and one component-control procedure frequently used in analogue outcome research was evaluated, and the results indicated that the control conditions were, in general, less credible than the therapy conditions.
1,417 citations
Book•
01 Jan 1972TL;DR: In this article, the authors present a reference handbook and research tool to improve measurement in the study of work organizations and to facilitate the teaching of introductory courses in this subject, focusing solely on work organizations, that is, social systems in which members work for money.
Abstract: Addresses the standardization of the measurements and the labels for concepts commonly used in the study of work organizations. As a reference handbook and research tool, seeks to improve measurement in the study of work organizations and to facilitate the teaching of introductory courses in this subject. Focuses solely on work organizations, that is, social systems in which members work for money. Defines measurement and distinguishes four levels: nominal, ordinal, interval and ratio. Selects specific measures on the basis of quality, diversity, simplicity and availability and evaluates each measure for its validity and reliability. Employs a set of 38 concepts ‐ ranging from “absenteeism” to “turnover” as the handbook’s frame of reference. Concludes by reviewing organizational measurement over the past 30 years and recommending future measurement reseach.
1,343 citations
TL;DR: A method for generating values of continuous symmetric random variables that is relatively fast, requires essentially no computer memory, and is easy to use is developed.
Abstract: A method for generating values of continuous symmetric random variables that is relatively fast, requires essentially no computer memory, and is easy to use is developed. The method, which uses a uniform zero-one random number source, is based on the inverse function of the lambda distribution of Tukey. Since it approximates many of the continuous theoretical distributions and empirical distributions frequently used in simulations, the method should be useful to simulation practitioners.
430 citations
361 citations
TL;DR: The problem of the stria terminalis projection field has been examined by use of two versions of the cupric‐silver technique as well as variations of the Fink‐Heimer and Nauta‐Gygax techniques applied to material fixed under different conditions using brains from very young rats surviving 30 hours to four days after production of lesions.
Abstract: The problem of the stria terminalis projection field has been examined by use of two versions of the cupric-silver technique as well as variations of the Fink-Heimer and Nauta-Gygax techniques applied to material fixed under different conditions using brains from very young rats surviving 30 hours to four days after production of lesions at different levels of the course of the stria terminalis and related structures. The findings are as follows:
(1)
A dorsal subventricular portion of the stria terminalis divides into retrocommissural and supracommissural contingents which together account for degenerating terminals seen in the ipsilateral bed nuclei of the stria terminalis and of the anterior commissure, and in the medial preoptic-hypothalamic junction area. The supracommissural bundle also disseminates into the laterobasal septum, nucleus accumbens, olfactory tubercle, the posterior and medial divisions of the anterior olfactory nucleus, and the granular layer of the accessory olfactory bulb. Additional fibers end in the paucicellular capsule of the ventromedial hypothalamic nucleus, also in a small lateral parvocellular tuberal nuclear area, and throughout the premammillary nuclei. A small truly commissural division of the dorsal component was traced to the contralateral cortical amygdaloid nucleus and to small clusters of medial amygdaloid cells.
(2)
A ventral juxtacapsular portion of the stria terminalis was traced to the ipsilateral strial bed nucleus, medial preoptic-hypothalamic junction area, the entire ventromedial hypothalamic nucleus, the lateral tuberal area and the premammillary nuclei. The lateralmost fibers of the dorsal strial component as well as those of the ventral component which lie lateral to the “commissural bundle” appear to terminate exclusively in the lateral portions of the bed nucleus of the stria.
(3)
A “commissural bundle” or component, after crossing the midline in the anterior commissure, ends in the bed nucleus of the posterior limb of the latter, in the olfactory tubercle, prepiriform cortex, lateral amygdaloid nucleus and the strial bed nucleus. It is thus a decussation rather than a commissure. No contribution from stria terminalis to stria medullaris could be identified.
349 citations
TL;DR: The similarities between birds and insects seem sufficient to indicate, at least provisionally, that the theory developed for insects applies also to birds with appropriate modifications for longer life span and more complex social behavior; comparisons between insects and fish lead to the same conclusion.
Abstract: Physiological and ecological results from a variety of species are consistent with what seem to be valid general statements concerning insect migration These are as follows: (i)During migration locomotory functions are enhanced and vegetative functions such as feeding and reproduction are suppressed (ii) Migration usually occurs prereproductively in the life of the adult insect (the oogenesis-flight syndrome) (iii)Since migrant individuals are usually prereproductive, their reproductive values, and hence colonizing abilities, are at or near maximum (iv) Migrants usually reside in temporary habitats (v)Migrants have a high potential for population increase, r, which is also advantageous for colonizers (vi)Both the physiological and ecological parameters of migration are modifiable by environmental factors (that is, phenotypically modifiable)to suit the prevailing conditions Taken together, these criteria establish a comprehensive theory and adumbrate the basic strategy for migrant insects This basic strategy is modified to suit the ecological requirements of individual species Comparative studies of these modifications are of considerable theoretical and practical interest, the more so since most economically important insects are migrants No satisfactory general statements can as yet be made with respect to the genotype and migration Certainly we expect colonizing populiations to possess genotypes favoring a high r, but genotypic variation in r depends on the heritabilities of life table statistics, and such measurements are yet to be made (10, 53) The fact that flight duration can be increased by appropriate selection in Oncopeltus fasciatus, and the demonstration of additive genetic variance for this trait in Lygaeus kalmii, suggest that heritability studies of migratory behavior would also be worth pursuing Most interesting of course, will be possible genetic correlations between migration and life history parameters Also, migration often transports genotypes across long distances with considerable mixing of populations An understanding of its operation therefore carries with it implications for population genetics, zoogeography, and evolutionary theory Finally, at least parts of the above general theory would seem to be applicable to forms other than insects Bird and insect migrations, for example, are in many respects ecologically and physiologically similar Birds, like insects, emphasize locomotory as opposed to vegetative functions during long-distance flight; the well-known Zugenruhe or migratory restlessness is a case in point Further, many birds migrateat nigt at a time when they would ordinarily roost(vegetative activity) Because their life spans exceed single seasons, bird migrants are not prereproductive in the same sense that insect migrants are, and hence reproductive values do not have the same meaning(but note that some insects are also interreproductive migrants) The situaion is complicated further by the fact that in many birds adult survivorship is virtually independent of age so that colonizing ability tends to be also (10, 54) Nevertheless, birds arrive on their nesting grounds in reproductive condition with the result that migration is a colonizing episode It is also phenotypically modifiable by environmental factors, some of which, for example, photoperiod, influence insects as well (55) The similarities between birds and insects thus seem sufficient to indicate, at least provisionally, that the theory developed for insects applies also to birds with appropriate modifications for longer life span and more complex social behavior; comparisons between insects and fish (56) lead to the same conclusion In birds especially, and also in other forms, various functions accessory to migration such as reproductive endocrinology, energy budgets, and orientation mechanisms have been studied extensively (55, 56) But there is need in vertebrates for more data andtheoy on the ecology and physiology of migratory behavior per se in order tobetter understand its evolution and its role in ecosystem function (5, 57) Migration in any animal cannot be understood until viewed in its entirety as a physiological, behavioral, and ecological syndrome
318 citations
01 Jan 1972
TL;DR: The connections of the amygdala have been extensively studied by Heimer and Nauta as discussed by the authors, who used the Fink-Heimer (1967) and electron microscopic methods to detect the connections.
Abstract: Much has been written about the connections of the amygdala, first of descriptions of normal material as stained with Weigert or Bielschowski type techniques, later of experimental material impregnated with Glees (1946) and Nauta-Gygax (1954) silver procedures. Reviews on the subject can be found in publications by Gloor (1955), Valverde (1965), Nauta and Haymaker (1969) and, in the present meeting, by Professor Lammers (1971). However, despite the pioneer value of such works, it was not until very recently that more reliable information has been produced, specifically by Heimer and Nauta (1969) who utilized the Fink-Heimer (1967) and electron microscopic methods. Further elaboration of their findings has been presented by Leonard and Scott (1971), who also employed the Fink-Heimer technique, and these contributions find strong support in additional electron microscopic observations by Raisman (1970, 1971).
291 citations
TL;DR: A realization for arbitrary logic function, using AND and EXCLUSIVE-OR gates, based on Reed-Muller canonic expansion is given that has many of these desirable properties of "easily testable networks".
Abstract: Desirable properties of "easily testable networks" are given. A realization for arbitrary logic function, using AND and EXCLUSIVE-OR gates, based on Reed-Muller canonic expansion is given that has many of these desirable properties. If only permanent stuck-at-0 (s-a-0) or stuck-at-1 (s-a-1) faults occur in a single AND gate or only a single EXCLUSIVE-OR gate is faulty, the following results are derived on fault detecting test sets for the proposed networks: 1) only (n/4) tests, independent of the function being realized, are required if the primary inputs are fault-free; 2) only 2n, additional inputs (which depend on the function realized) are required if the primary inputs can be faulty, where n, is the number of variables appearing in even number of product terms in the Reed-Muller canonical expansion of the function; and 3) the additional 2ne inputs are not required if the network is provided with an observable point at the output of an extra AND gate.
278 citations
TL;DR: In the mammalian cerebellum, a new type of junction which resembles the septate junctions (SJs) of invertebrate epithelia is observed between axonal branches forming the tip of the brush of basket fibers around the initial segment of the Purkinje cell axon.
Abstract: "Gap" junctions, the morphological correlate for low-resistance junctions, are demonstrated between some mossy fiber terminals and granule cell dendrites in some lower vertebrate cerebella (gymnotid and frog). Most of the gap junctions (GJs) seen in the gymnotid-fish cerebellum exhibit an asymmetrical configuration, the electron-opaque cytoplasmic material underlying the junction being more extensive in the dendritic than in the axonal side. In the frog cerebellum, the GJs have a symmetrical distribution of such electron-opaque material. In both species the GJs are encountered at the same synaptic interface as the conventional synaptic zone (CSZ), constituting "mixed synapses" in a morphological sense. The axonal surface covered by CSZs is larger than that covered by GJs. In mammalian cerebellum, GJs are observed only in the molecular layer, between perikarya, dendrites, or perikarya and dendrites of the inhibitory interneurons. These GJs are intermixed with attachment plates and intermediary junctions interpreted as simply adhesive. In the mammalian cerebellum, a new type of junction which resembles the septate junctions (SJs) of invertebrate epithelia is observed between axonal branches forming the tip of the brush of basket fibers around the initial segment of the Purkinje cell axon. It is suggested that such junctions may be modified forms of septate junctions. The physiological implications of the possible existence of high-resistance cross-bridges between basket cell terminals, which may compartmentalize the extracellular space and thus regulate extracellular current flow, must be considered.
213 citations
TL;DR: During the rainy season bird-flowered plants at high elevations are more effectively pollinated than closely related bee-flowers plants.
Abstract: During the rainy season bird-flowered plants at high elevations are more effectively pollinated than closely related bee-flowered plants With good flight conditions the effectiveness of birds and bees is essentially equal Thus, the higher incidence of bird flowers at higher elevations is attributable in part to the competitive advantage gained through greater reproductive success
196 citations
TL;DR: The data show that cholesterol in both its free form and its ester form is depleted from experimentally induced coronary atheromatosis by dietary regression regimens, and suggest that most of the cholesterol depletion occurs during the first half of regression.
Abstract: Lipids were measured in the coronary arteries of monkeys on an atherogenic diet and in the arteries of matched monkeys on the atherogenic diet followed by regression diets. Cholesterol content was 51 mg/g dry weight in the arteries of monkeys with atheromatosis; after 40 months on the regression diets it was 18 mg/g. Cholesteryl ester was 69% lower and free cholesterol 53% lower after the regression diets. Decreases in triglycerides and phospholipids were not significant. The cholesterol content of the arteries of two monkeys autopsied after 20 months on the regression diets was close to the mean value after 40 months. The data show that cholesterol in both its free form and its ester form is depleted from experimentally induced coronary atheromatosis by dietary regression regimens. The data also suggest that most of the cholesterol depletion occurs during the first half of regression; the susceptibility of the residual excess arterial cholesterol to mobilization from the vessel wall by dietary means is questionable.
TL;DR: The finding that this patient showed essentially normal ability to discriminate unfamiliar faces supports the contention that prosopagnosia cannot be solely explained in terms of a general visuoperceptive impairment.
TL;DR: A method is described, which is capable of fractionating histones obtained from any animal source into five major groups, and possesses the considerable advantage that the starting material is whole histone rather than a nucleoprotein preparation.
Abstract: A method is described, which is capable of fractionating histones obtained from any animal source into five major groups. Although the method is based on procedures initially developed by E. W. Johns (1964), involving differential solubility in solutions of acids and of ethanol, it gives a cleaner separation and possesses the considerable advantage that the starting material is whole histone rather than a nucleoprotein preparation.
TL;DR: The heme-polypeptide interactions in cytochrome c must be essential to stabilization of the globular conformation of the native protein.
TL;DR: In this paper, the first results of satellite experiments to measure magnetospheric convection electric fields using the double-probe technique were compared with the initial findings of the electric field experiment on the polar orbiting OGO-6 satellite.
Abstract: This paper reviews the first results of satellite experiments to measure magnetospheric convection electric fields using the double-probe technique. The earliest successful measurements were made with the low-altitude (680-2530 km) polar orbiting Injun-5 spacecraft. The Injun-5 results are compared with the initial findings of the electric field experiment on the polar orbiting OGO-6 satellite. Electric field measurements from the OGO-6 satellite have substantiated many of the initial Injun-5 observations with improved accuracy and sensitivity. The OGO-6 detector revealed the persistent occurrence of anti-sunward convection across the polar cap region at velocities not generally detectable with the Injun-5 experiment. The OGO-6 observations also provided information indicating that the location of the electric field reversal shifts equatorward during periods of increased magnetic activity. The implications of the electric field measurements for magnetospheric and auroral structure are summarized, and a list of specific recommendations for improving future experiments is presented.
TL;DR: The inability to regulate water intake in the absence of food, one of the characteristic and long lasting effects of the LH syndrome, appears to be due to destruction of the NSB and the consequent decline in telencephalic content of catecholamines.
TL;DR: In this paper, a local-time survey of low energy proton and electron intensities precipitated into the earth's atmosphere during periods of magnetic quiescence was constructed, where the main contributors to electron energy influx are inverted V precipitation poleward of the trapping boundary and the plasma sheet intensities equatorward.
Abstract: A local-time survey of the low energy proton and electron intensities precipitated into the earth's atmosphere during periods of magnetic quiescence was constructed. A typical, individual satellite crossing of this region in each of eight local-time sectors was selected from a library of similar observations with the polar-orbiting satellite Injun 5. The trapping boundary for more energetic electron intensities, E 45 keV, is a natural coordinate for delineating the boundary between the two major types of lower energy, 50 or = E or = 15,000 eV. The main contributors to electron energy influx are inverted V precipitation poleward of the trapping boundary and the plasma sheet intensities equatorward. These are interpreted in terms of a magnetospheric model.
TL;DR: Hundreds of thousands of people suffer from thermal burns each year in the United States; prior to the development of modern treatments such as sulfamylon, silver nitrate, and sophisticated supportive measures, many of these patients survive.
Abstract: Hundreds of thousands of people suffer from thermal burns each year in the United States. Prior to the development of modern treatments such as sulfamylon, silver nitrate, and sophisticated supportive measures, those with severe and mutilating burns usually died. Now many of these patients survive. To be burned is an intensely traumatic experience— catastrophic, painful, deforming, debilitating, and even dirty, because of the invariable presence of infection. Further, the burn victim, unlike most other victims of trauma, must continue to wear the badge of his trauma for the rest of his life.
TL;DR: In this article, the authors examined the role of nutritional factors and the significant role they played in the causation of atherosclerosis and coronary heart disease and how to correct hyperlipidemia with a low cholesterol, moderately low fat diet.
TL;DR: It is postulated that electron-withdrawing and electron-donating groups at the N1-position influence the strength of the hydrogen bonds which form and, hence, the tendency of these compounds to exhibit more than one crystalline form.
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TL;DR: In this paper constructions are given for combining two, three, or four codes to obtain new codes, many of which have more codewords than any comparable code previously known to us.
Abstract: In this paper constructions are given for combining two, three, or four codes to obtain new codes. The Andryanov-Saskovets construction is generalized. It is shown that the Preparata double-error-correcting codes may be extended by about (block length) ^{1/2} symbols, of which only one is a check symbol, and that e -error-correcting BCH codes may sometimes be extended by (block !ength) ^{1/e} symbols, of which only one is a check symbol. Several new families of linear and nonlinear double-error-correcting codes are obtained. Finally, an infinite family of linear codes is given with d/n = \frac{1}{3} , the first three being the (24,2^12, 8) Golay code, a (48,2^15, 16) code, and a (96,2^18, 32) code. Most of the codes given have more codewords than any comparable code previously known to us.
TL;DR: Differences exist over very short segments of the esophagus, in the nerves, muscle, or both, which may partially account for peristaltic movements.
TL;DR: In this article, a comparison of low-energy charged-particle intensities measured with the low-altitude satellite Injun 5 and a ground-based observation of an auroral arc at Fort Churchill on December 21, 1968, during late local evening has established that an intense precipitation band of electron intensities provides the primary energy influx for the auroral light.
Abstract: A comparison of low-energy charged-particle intensities measured with the low-altitude satellite Injun 5 and a ground-based observation of an auroral arc at Fort Churchill on December 21, 1968, during late local evening has established that an intense precipitation band of electron intensities provides the primary energy influx for the auroral light. This precipitation event was located poleward of and adjacent to the trapping boundary for more energetic electron (above 45 keV) intensities. Proton and electron intensities similar to those in the plasma sheet in the magnetotail were observed in a substantially less-intense zone positioned equatorward of and adjacent to the trapping boundary. The intense precipitation band of electron intensities poleward of the trapping boundary is interpreted as the signature of direct acceleration of magnetosheath electrons into the earth's atmosphere.
TL;DR: Flesh points on the tongue body of two normal speakers were simulated by attaching small radiopaque markers to the lingual surface by lateral-view cinefluorography.
Abstract: Flesh points on the tongue body of two normal speakers were simulated by attaching small radiopaque markers to the lingual surface. Lateral-view cinefluorography was used to record the displacement...
TL;DR: In this paper, the authors examined the interactions between the intestinal flagellate, Hexamita muris, and the epithelial cells of the duodenal crypts where trophozoites of this parasite were particularly concentrated in infected rats.
TL;DR: Field and intracellular potentials recorded at the level of the trochlear nucleus (TN) following stimulation of the ipsi- or contralateral vestibular nerve (Vi, Vc) or the cerebellar flocculus (Floc).
Abstract: Field and intracellular potentials were recorded at the level of the trochlear nucleus (TN) following stimulation of the ipsi- or contralateral vestibular nerve (Vi, Vc) or the cerebellar flocculus (Floc). Vi and Vc stimulation produced clear presynaptic field potentials in the TN as the vestibulo-trochlear volleys ascending from the vestibular nucleus reached the trochlear motoneurons (TMns). Paired Vi-Vi or Vc-Vc stimulation at different intervals demonstrated a clear depression of the second of the two presynaptic potentials in the TN. A similar finding was obtained intracellularly from TMns. These results indicate a marked reduction in the excitability of the vestibular neurons following the conditioning stimulus. This period of subnormality may last for as long as 40 msec. Electrical stimulation of Vi and Vc generated an IPSP and EPSP respectively in TMns. In most instances these synaptic potentials occurred in a repetitive fashion after a single stimulation to either nerve. This reverberatory-like tendency of the vestibulo-trochlear pathways was absent in decerebellate animals, implying a cerebellar modulatory mechanism on vestibulo-trochlear transmission. Floccular stimulation produced a strong monosynaptic depression of the field and intracellular potentials evoked in the TN by Vi activation. In chronic experiments where the vestibular nerve had been transected, Floc stimulation generated a disinhibition of TMns through its suppression of the ipsilateral inhibitory vestibular neurons which project to the TN. Contralateral Floc stimulation produced a clear disfacilitation of TMns by the inhibition of contralateral excitatory vestibular neurons. Direct evidence was obtained for commissural inhibition acting on both the inhibitory and excitatory vestibular neurons projecting to the TN. The functional implications of the interaction between ipsi- and contralateral vestibular nuclei and the cerebellum and vestibular nuclei are considered in the Discussion.
TL;DR: A new approach is described for increasing the dissolution rates of relatively insoluble powders by equilibration of the drug in an organic solvent on an insoluble excipient with an extensive surface based on the concept of increasing the surface available for contact with dissolution media.