Showing papers by "University of Illinois at Chicago published in 1969"
TL;DR: The mesiobuccal roots of 208 teeth were sectioned buccolingually from the mesial aspect and the canal configurations were categorized as discussed by the authors, and the frequency of occurrence of the bifurcated or double canal must be taken into consideration when surgical treatment is planned and as a possible cause of otherwise unexplained failure.
285 citations
TL;DR: In this paper, a variational technique based on two different inequalities for the Helmholtz free energies is used to calculate the equilibrium thermodynamic properties of simple fluids, and a system with hard-sphere potential function is used as the reference system.
Abstract: A variational technique which is based on two different inequalities for the Helmholtz free energies is used to calculate the equilibrium thermodynamic properties of simple fluids. A system with hard‐sphere potential function is used as the reference system. Helmholtz free energy of the original system is calculated by variation around the Helmholtz free energy of the reference system, and the other thermodynamic properties are calculated from free energy. By choosing a hard‐sphere reference system, it is possible to calculate the equilibrium thermodynamic properties of fluids from very low densities to densities close to solid, and from high temperatures in the gas phase to low temperatures in the liquid phase, in the ranges where experimental and machine‐calculated data are available. It is shown that the present variational technique is a better approach to the prediction of the equilibrium thermodynamic properties of liquids and vapor–liquid phase transition than any other approach so far developed. W...
222 citations
TL;DR: It is shown that bees are highly responsive to plant spacing and that bee-mediated pollen dispersal and associated gene dispersal is strongly correlated with plant spacing, the plant species and floral mechanism notwithstanding.
Abstract: Pollen dispersal and pollen-mediated gene dispersal in flowering plants are effected primarily by animals and air currents. It is generally accepted that the dispersal of pollen within a colony of a given species is under the control of these agents and beyond the control of the colony. This view may be valid in the case of anemophilous plants where alterations of colony parameters ostensibly would have no effect upon the characteristics of pollen flow, since these parameters would not affect the transferal agent. However, in entomophilous plants, pollen and associated gene movements are mediated by vectors which may be sensitive to stimuli emanating from the colony. If pollinators respond to such stimuli, permutations of which would alter foraging behavior, the colony, wittingly or unwittingly, would control the dispersal of its pollen and genes. A recent study on pollinator flight patterns in Liatris aspera (Levin and Kerster, 1969) has shown that plant density and spacing control the feeding-flight behavior of bees and the movement of pollen which they bear. The present investigation was undertaken to determine whether the dependence of bee-flight characteristics and bee-mediated pollen dispersal upon plant spacing is a general phenomenon. We will show that bees are highly responsive to plant spacing and that bee-mediated pollen dispersal and associated gene dispersal is strongly correlated with plant spacing, the plant species and floral mechanism notwithstanding.
190 citations
TL;DR: Doleserpeton is unique among nonlissamphibian tetrapods in that it possesses pedicellate, bicuspid teeth together with nearly monospondylous vertebrae in which the main central element is a pleurocentrum.
Abstract: A new genus and family of rhachitomous labyrinthodont amphibian, related to the Upper Paleozoic Dissorophidae and Trematopsidae, may be ancestral to some or all of the modern Amphibia. Doleserpeton occurs in Lower Permian fissure fill deposits in southwestern Oklahoma. It is unique among nonlissamphibian tetrapods in that it possesses pedicellate, bicuspid teeth together with nearly monospondylous vertebrae in which the main central element is a pleurocentrum. Doleserpeton may have been utilizing the food resources of the upland, terrestrial environment in a novel fashion for rhachitomes.
190 citations
188 citations
177 citations
TL;DR: In this paper, the authors describe an extension of a popular method of solving second-order ordinary differential equations with two end-point boundary conditions to nth-order ODEs and to partial differential equations that are second order in one direction.
Abstract: The purpose of this note is to describe the simple extension of a popular method of solving second-order ordinary differential equations with two end-point boundary conditions to nth order ordinary differential equations and to partial differential equations that are second order in one direction. The orginal method is simply a version of Gaussian elimination; and the extension (to be described) has, we have discovered, been published, sliihtly differently, before. We feel, however, that the present note will be of value, since the extension has proven very useful to both of us, and is seldom used among numerical analysts and meteorologists. We begin by reviewing second-order ordinary differential equations. Consider 8x is the grid interval used in finite-difference approximation to equation (1),
172 citations
TL;DR: The results support the concept of dual hypothalamic feeding systems in the medial and lateral regions and suggest, however, that other neural or hormonal mechanisms may contribute to the hyperphagia-obesity syndrome.
170 citations
TL;DR: This report is based on the review of the cardiac findings at necropsy in 31 patients who died in the early postoperative period following single or multiple valve replacement at the Presbyterian-&.
155 citations
TL;DR: Reasonable grounds exist for asserting that there is a significant relationship of psychological factors to nonorganic TMJ dysfunction, that these factors can be treated, and that this treatment results in relief of physical symptoms as well.
Abstract: Reasonable grounds exist for asserting that there is a significant relationship of psychological factors to nonorganic TMJ dysfunction, that these factors can be treated, and that this treatment results in relief of physical symptoms as well.
146 citations
TL;DR: In this paper, the Mandel-Cryer effect is analyzed in terms of its physical motivation and influence on failure conditions and the lateral distribution of excess pore pressure and maximum shear stress.
Abstract: This paper analyzes the one-, pseudo three- and three-dimensional theories of consolidation. The particular problem of a strip load on a half-plane is solved for the complete stress field. The Mandel-Cryer effect is noted and analyzed in terms of its physical motivation and influence on failure conditions. Attention is drawn to the lateral distribution of excess pore pressure and maximum shear stress. The effect of pore pressure spreading is noted. Three-dimensional pseudo and three-dimensional theories are compared. The pseudo theory is not a good approximation to three-dimensional consolidation. An analysis of thick clay layers is made using London clay an an example. Predictions of the progress of consolidation by three-dimensional theory are approximately one order of magnitude faster than by conventional theory. It is concluded that three-dimensional theory models the consolidation process better than other comparable theories. It is recommended that field experience by developed to enable appropriate interpretation of this theory.
TL;DR: Many variables determine how a person acquires a TMJ problem, how he reacts to it, and how he responds to therapy, and it is necessary to subdivide the total patient population in accordance with those variables.
Abstract: Many variables determine how a person acquires a TMJ problem, how he reacts to it, and how he responds to therapy. Although clinical symptoms may be similar among TMJ patients, it is necessary to subdivide the total patient population in accordance with those variables. Only in this way can a meaningful diagnosis and a rational approach to therapy be provided for each individual patient.
TL;DR: In this article, the authors discuss the judgment process as the means by which a person measures certain of his or her cognitions and perceptions and discuss theories of judgment in terms of that model.
Abstract: Publisher Summary This chapter discusses the judgment process as the means by which a person measures certain of his or her cognitions and perceptions. It introduces concept of the personal reference scale as a device for subjectively representing a set of stimuli. A reference scale measures a subjective quantity. The chapter develops logical criteria for inferring sameness and difference of quantity and scale and describes heuristic model of the reference scale for application in those situations in which it can be assumed that a reference scale and a physical scale measure the same quantity, or that two reference scales measure the same quantity. The chapter discusses theories of judgment in terms of that model. Theories of judgment, some of which have been contributed by social psychologists and some by psychophysicists, were surveyed in terms of the reference scale model. Most of them, it was revealed, can be viewed as theories of scale, rather than as theories of subjective quantities. Furthermore, all were seen to be fragmentary, referring primarily to one component of the reference scale model. An adequate theory of judgment would surely encompass all facets of the judge's reference scale.
TL;DR: Embryologically in single ventricle the authors are dealing with persistence of the primitive state of the bulboventricular loop, due to a lack of expansion of the atrial canal to the right during the process of absorption of the bulbus.
Abstract: Single ventricle is that condition in which both atrioventricular (A-V) orifices enter a common ventricular sinus, from which the arterial trunks emerge with their coni. The following types of single ventricle were found: (1) with regular (noninverted) transposition in levocardia; (2) with inverted transposition in levocardia; (3) with normal position of arterial trunks in levocardia; (4) in dextrocardia, and (5) in mesocardia. This entity is differentiated from common ventricle which is basically a heart with a large ventricular septal defect. Single ventricle does not include mitral and tricuspid atresia by definition, nor does it include straddling tricuspid orifice, in which two distinct ventricles are present. The concept of single ventricle herein defined differs from de la Cruz and Miller's concept of double-inlet left ventricle which includes straddling tricuspid orifice. Embryologically in single ventricle we are dealing with persistence of the primitive state of the bulboventricular loop, due to a lack of expansion of the atrial canal to the right during the process of absorption of the bulbus.
TL;DR: Size of lesion and age at operation were major factors in determniting the degree of behavioral change in free-ranging rhesus monkeys.
Abstract: The eflect of uncinectomny on the social behavior of free-ranging rhesus monkeys was observed on Cayo Santiago Island. Operated subjects showed social indifjerence, failed to display appropriate aggressive and submissive gestures. were expelled from their social group, and evenitlually died. Two juvenile subjects with the lesion restricted to amygdala survived and have rejoinied their social group. Size of lesion and age at operation were major factors in determniting the degree of behavioral change.
TL;DR: Natural mammalian hibernation was continuously maintained under laboratory conditions throughout spring and summer seasons in a colony of thirteen-lined ground squirrels by serial transfusional passage of blood from hibernations animals to active animals.
Abstract: Natural mammalian hibernation was continuously maintained under laboratory conditions throughout spring and summer seasons in a colony of thirteen-lined ground squirrels by serial transfusional passage of blood from hibernations animals to active animals. This procedure successfully produced hibernation in animals until late summer, at which time naturally occurring (spontaneous) hibernations occurred in the colony, thus terminating the experiment.
TL;DR: It is found that incidence of CHD in this cohort was associated with educational status, but that the form of the relationship varied according to the clinical form by which the disease was first manifested.
TL;DR: A method is derived to calculate the burst distribution from the simple partitioned Markov chain model and the calculated result is compared with the Burst distribution simulated from the actual error data collected from the HF communication link between Chicago and San Diego.
Abstract: A simple partitioned Markov chain model was proposed recently for characterization of the HF channel. The model is uniquely determined by the gap distribution. In this paper a method is derived to calculate the burst distribution from the model. The calculated result is compared with the burst distribution simulated from the actual error data collected from the HF communication link between Chicago and San Diego by IIT Research Institute for the Naval Electronics Laboratory Center. The model is also applied to a random channel and the result is compared with the simulation from the error sequence generated by a random number generator. In both cases there is a good agreement between the calculated and simulated results. It is illustrated that the model can be used for evaluating and designing the error detecting and correcting codes for the HF channel. The model is flexible as the number of states is not rigidly fixed hence it could be applied to a wide variety of HF channels. There is some indication that the model correlates to the multipath reduction factor (MRF). If verified it could add significance to the model since the maximum usable frequency (MUF) can be determined many months ahead by the available propagation prediction.
TL;DR: In this article, the Paley design admits automorphism groups which are transitive on incident point-block pairs but are not 2-transitive on points, and the results of these results generalize many results of Liineburg [13] whose approach is different.
Abstract: From a geometric point of view, the most interesting designs (see w 2 for definitions) are generally those admitting fairly large automorphism groups. The methods of finite permutation groups may be applied to such designs, and vice versa, as in [5, 6, 8, 11, 13 and 143. We shall prove several general results which are useful in the study of automorphism groups of designs, and then use some of these to characterize some designs admitting large automorphism groups. Further applications are found in [11]. A Hadamard design is a symmetric design with k = (v- 1)/2 (see [3] or [17] for the connection with Hadamard determinants). The best known examples of such designs - other than the Desarguesian projective spaces over GF(2) - are the Paley designs ([15]; cf. [183 and [11]). The points of a Paley design are the elements ofF = GF(v), where v > 3 is a prime power -=- 3 (rood 4), while the blocks are the translates under F + of the set Q of non-zero squares of F. This design admits an automorphism group of odd order {x --+ x ~ t + a[t E Q, a ~ F, ~Aut(F)} which is transitive on incident point-block pairs; this group is not always the full automorphism group (cf. [11]). Theorem 1.1. Paley designs are the only Hadamard designs admitting automorphism groups which are transitive on incident point-block pairs but which are not 2-transitive on points, A larger class of designs will also be considered, all related to F. Our characterizations of some of these designs generalize many of the results of Liineburg [13], whose approach is different.
TL;DR: Most of the data indicate that excess free acetylcholine in the brain increases seizure susceptibility, whereas norepinephrine decreases it.
Abstract: SUMMARY
The influence on seizure susceptibility of changed concentrations of free neurotransmitters at their receptor sites in brain has been examined in the light of findings from two approaches to the problem. The first involves direct observations of the effects of intracarotid, intracisternal or intraventricular injections of the neurohumors as well as the local application of these chemicals to exposed brain tissue. The second involves inferences drawn from the actions of a variety of drugs that alter the synthesis, storage, release or reuptake of the transmitters. Most of the data indicate that excess free acetylcholine in the brain increases seizure susceptibility, whereas norepinephrine decreases it. Dopamine, serotohin^and y-aminobutyric acid appear to have anticonvulsant activity, but the evidence is less persuasive than that for norepinephrine.
RESUME
Ľinfluence des changements de concentration des neurotransmetteurs libres au niveau de leurs recepteurs dans le cerveau sur la susceptibilityeaľegard de crises a eteetudiee a la lumiere des constatations faites suivant deux manieres differentes ďaborder le probleme. La premiere de ces methodes repose sur des observations directes des effets ďinjections intra-carotidiennes, intra-cisternales ou intra-ventriculaires de neuro-humeurs ainsi que des effets ďapplications locales de ces substances chimiques sur des tissus cerebraux mis a nu. La deuxieme se fonde sur des deductions tirees des effets de differents medicaments qui entrainent des modifications dans la synthese, la mise en reserve, la liberation ou la re-absorption des transmetteurs. La plupart des donnees ainsi recueillies indiquent qu'un exces ďacetylcholine libre dans le cerveau augmente la susceptibilitye aux crises tandis que la norepinephrine la diminue. La dopamine, la serotonine et ľacide gamma-aminobutyrique semblent avoir une activite anticonvulsive, mais les indications dans ce sens sont moins probantes que pour la norepinephrine.
TL;DR: The normal coagulation process is currently viewed as a sequential interaction of several co-agulation factors (and platelet phospholipid) leading to fibrin formation.
TL;DR: Five uraemic patients in whom deafness followed ethacrynic-acid treatment are described, and in three the deafness was permanent.
TL;DR: Quantitative analyses were made of carbohydrates and amino acids in Collocalia mucoid, finding that the most abundant amino acids are serine, threonine, aspartic acid, glutamic acid, proline, and valine.
TL;DR: The physical characteristics of the nodule and other findings on physical examination did not reliably differentiate between benign and malignant solitary nodules, and it is advised that solitary thyroid nodules should be excised.
TL;DR: In this article, the storage and loss moduli were measured for laminated glass fiber reinforced epoxy composite beams at frequencies up to 9400 Hz, with relatively insensitive storage moduli.
Abstract: Measurements of storage and loss moduli are reported for laminated glass fiber reinforced epoxy composite beams at frequencies up to 9400 Hz. The storage moduli were relatively insensitive and the ...
TL;DR: Findings suggest the presence of a transhydrogenase activity in intact erythrocytes and it appears that NAD + content may be influenced by factors other than those affecting glycolysis directly.
TL;DR: It is indicated that extrarenal erythropoietin is probably identical to that of renal origin, and its production is regulated by the intensity of hypoxia.