Showing papers by "University of Oklahoma published in 1974"

Measured Turbulence and Its Effect on Thrombus Formation

Abstract: Turbulence is one of the hydraulic disturbances implicated in thrombus formation, even though absolute proof of its contributory effect is lacking. Because of the importance of a possible effect of turbulence on thrombus formation, the relation was studied in eight dogs. In each dog, two arteriovenous shunts were established, one from each femoral artery to the contralateral femoral vein. Only one shunt contained a turbulence-producing device; otherwise, the shunts were identical in shape, size, and material. The intensity of turbulence distal to the turbulence generator was quantified in vitro by measuring the relative magnitude of the randomly fluctuating velocities. In each of the eight dogs, more thrombi, by weight, accumulated in the turbulent shunt than in the laminar shunt (P < 0.001). Thrombi from the turbulent shunt weighed 180 ± 30 (SE) mg, whereas those from the laminar shunt weighed 0.9 ± 0.6 mg. The weight of thrombi that accumulated within the turbulent system appeared to be related to the i...

An Empirical Comparison of the Anova F-Test, Normal Scores Test and Kruskal-Wallis Test Under Violation of Assumptions

Abstract: The present research compares the ANOVA F-test, the Kruskal-Wallis test, and the normal scores test in terms of empirical alpha and empirical power with samples from the normal distribution and two exponential distributions. Empirical evidence supports the use of the ANOVA F-test even under violation of assumptions when testing hypotheses about means. If the researcher is willing to test hypotheses about medians, the Kruskal-Wallis test was found to be competitive to the F-test. However, in the cases investigated, the normal scores test was not consistently better than the F-test or the Kruskal-Wallis test and could not be recommended on the basis of this research.

Composite Material Mechanics: Structural Mechanics

Abstract: Introduction T purpose of this Survey is to review and bring together in an orderly fashion some of the principal contributions to the field of structural mechanics of structures containing composite materials. The topics of micromechanics and fracture, while quite important, are not considered in this Survey. Emphasis is given to the macromechanical structural analysis of various structural elements, including response under conditions of stable static loading, buckling, and dynamics. The Survey unfolds in the following sequence: Straight and Curved Laminated Bars, Laminated Plates, Laminated Shells, Sandwich Structures, Applications to Practical Structural Systems, and Future Trends. The authors hope that this contribution will be a useful reference tool for researchers and engineers already involved in structural aspects of advanced composites, as well as for those who are just entering the field. No Survey can do full justice to such a wide field as compositematerial structural mechanics. The references cited give only a glimpse of the extensive literature in this field. The authors apologize for not citing a number of important contributions in the field.

Effects of Music on Physiological Response

Abstract: For this study the heart rates of twenty-two members of a college-level music appreciation class were recorded while students listened to the first movement of Beethoven's fifth symphony. The measu...

Chromosome evolution in the genus Dipodomys and its taxonomic and phylogenetic implications.

Abstract: The mitotic chromosomes of 18 species of kangaroo rats, Dipodomys , are evaluated as indicators of relationships between species and species-groups Five major species groups, similar to those based on morphological data (Lidicker, 1960), are indicated from karyotypic studies. However, some important rearrangements in these groups both in content and linear order seem necessary as D. microps and D. deserti are placed in the Heermanni Group. The origins and phylogenetic relationships of the species-groups and lines of sibling species are discussed.

Thermoregulatory function of the parietal eye in the lizard Anolis carolinensis.

Abstract: Animals were acclimitized to a daily cycle of 15-25°C and a photoperiod of LD 12:12. Parietalectomized animals in an experimental thermal gradient (15°C-40°C, LD 12:12) selected significantly higher temperatures than controls at all hours of the day except from 0800-1200. These results suggest that the lizard parapineal plays a direct role in thermoregulation in addition to the indirect function as an illuminometer.

Relationship between nutrient concentration, phytoplankton density, and zooplankton density in nutrient enriched experimental ponds

Abstract: The effects of different levels of nutrient input on the plankton community was investigated in a two-year controlled fertilization study of eight experimental ponds. There were four treatments, each replicated: a control, to which no fertilizer was added, and three levels of nutrient addition. Limnological parameters including phytoplankton and zooplankton densities were measured frequently during both summers and less frequently during the rest of the year. Inorganic nitrogen and phosphorus concentrations in the treated ponds increased. Phytoplankton and zooplankton density increased with treatment level but was variable. There was a limited relationship between the average chlorophyll a concentration per summer and the average cladoceran dry weight per summer. Above chlorophyll a concentrations greater than 60–70 mg/m3 other factors such as a pH zooplankton mortality effect, prevailed.

Breath Analysis as a Technique in Clinical Chemistry

Abstract: Breath possesses unique advantages as a specimen for clinical chemical analyses, including the continuous equilibrium of gases and volatile substances between expired alveolar air and the pulmonary blood circulation. Substances amenable to analysis in breath include O2, CO2, CO, and other gases, volatile organic compounds, and many drugs with sufficiently high vapor pressures at physiological temperatures. Practical aspects of breath sampling and breath analysis are discussed, exemplified by breath-alcohol analysis. The requirements for obtaining breath samples in equilibrium with the pulmonary blood circulation are delineated, and experimental data are presented for the significant breath-sample characteristics bearing on design of breath collection and storage systems (end-expiratory temperature, breath volumes).

Ultraviolet-induced individual cell keratinization.

Abstract: Characteristic cells have been demonstrated as being individually dispersed throughout the superficial epidermis 24 h after being exposed to ultraviolet light. These „sunburn cells” with cosinophilic cytoplasm and pyknotic nuclei observed by light microscopy are also observed to be dyskeratotic by using electron microscopy.

Isolation of Skin Test-Active Preparations from Yeast-Phase Cells of Blastomyces dermatitidis

Abstract: Cell wall and cytoplasmic fractions were isolated from mechanically disrupted yeast-phase cells of Blastomyces dermatitidis in an effort to obtain a reliable skin-test antigen. The biological activities of these fractions were compared with those of two blastomycin preparations. The cytoplasmic antigens exhibited a low index of specificity yet exceeded the specificities of the blastomycins. The skin test-active component(s) of the cytoplasmic material had a molecular weight between 10,000 and 30,000 and could easily be concentrated by ultrafiltration on a PM-10 membrane. Unlike the cytoplasmic antigens and blastomycins, an alkali-soluble, water-soluble cell wall antigen effectively distinguished guinea pigs that were sensitized to B. dermatitidis from those sensitized to Histoplasma capsulatum. The biological activity of the yeast-phase antigen could be quantitated, on a weight basis, after purification by ultrafiltration (PM-10 membrane).

Student-faculty evaluation.

Abstract: Desirable attributes of SFE can be vitiated by its premature utilization in a formal and quantitative sense. This is because it is possible to teach for a specific student evaluation, given a particular questionnaire. Consequently, because of the importance of SFE, the questionnaire must be designed to meet the expectations of the students, as well as the aspirations of the respective institutions. Indiscriminate use of SFE will increase the gap between first-rate and second-rate institutions-first-rate institutions will continue to attract more demanding students, a fact that will be reflected in SFE's, whereas second-rate institutions, in an effort to maintain levels of enrollment, may tend to formulate SFE's that emphasize popularity and mediocrity of education. Careful construction of the format of SFE, on the other hand, could do much toward increasing the quality of teaching, as well as the motivation of students and teachers, in many institutions.

Sinusoidal response of composite-material plates with material damping.

Abstract: A general forced-vibration analysis is presented for laminated anisotropic rectangular plates including material damping. The theory used is the laminated version of the Mindlin plate theory and includes thickness-shear flexibility and rotatory and coupling inertia. A solution is obtained by the Rayleigh-Ritz method, extended to include the energy dissipated and the work done by the excitation. The analysis is applied to prediction of the resonant frequencies and associated nodal patterns and damping ratios of the first five modes for a series of rectangular plates with free edges. The plates considered consist of unidirectional boron-fiber/epoxy composite material with respective fiber orientations of 0, 10, 30, 45, 60, and 90 deg.

Degradative Effect of Phenol on Endotoxin and Lipopolysaccharide Preparations from Serratia marcescens

Abstract: It has been established that the well-known deproteinizing action of hot 45% aqueous phenol on whole cells or isolated and purified endotoxin of Serratia marcescens 08 is caused by the cleavage of a phenol-sensitive linkage within the lipid moiety. As a result of this degradation, both the lipopolysaccharide and simple protein fragments retained a part of the lipid moiety. Although not proceeding at the same fast rate as the cleavage of the lipid moiety, such phenol treatment also caused a partial hydrolysis of the O-specific side chain and ester-bound fatty acids. Hydrolysis of the O-specific side chain accounted for 5% of the lipopolysaccharide and that of ester-bound fatty acids accounted for 11% of the total fatty acid content after 60 min of treatment. It is suggested that the presence of these degradation products is one of the main causes of the heterogeneity of endotoxin and lipopolysaccharide preparations.

Transvenous management of pulmonary embolic disease

Abstract: Clinical pulmonary embolic disease was categorized into four classes according to hemodynamic and respiratory effects of the occlusion at the time of diagnosis. A new approach to management of massive embolization (Class III and IV) by transvenous catheter embolectomy was attempted in ten patients with initial success in eight. Three additional deaths occurred postoperatively, two from recurrent embolization prior to vena caval plication. In view of this preventable complication, a wire filter device was developed for insertion at the time of embolectomy. The filter has also been utilized in 15 additional patients with lesser degrees of embolization (Class II). The conal shape of the device permits preservation of flow after embolic capture and followup venacavagrams in nine patients up to 20 months postoperative shows patency in all. Complications occurred in both groups related both to the underlying disorder and to the catheter technics.

Prostaglandins of rat testis

Abstract: The purpose of the study was to determine whether prostaglandins were present in mammalian testis, a tissue that has a large concentration of polyenoic fatty acids that are potential precursors of prostaglandins. Acid-soluble lipids of rat testis were extracted, purified, and fractionated by thin layer and column chromatographies.3H-Prostaglandins were added as internal reference standards to monitor recoveries and facilitate identification. Initial identification of prostaglandin species was done by chromatography. Further identification was done by elution of the prostaglandin zones followed by rechromatographies (both thin layer and column), measurements of UV absorption spectra, and by gas liquid chromatography. The results of these analyses indicate that prostaglandin E1, 11α,15(S)-dihydroxy-9-oxo-β-trans-prostenoic acid; prostaglandin E2, 11α-15(S)-dihydroxy-9-oxo-5-cis-13-trans-prostadienoic acid; and prostaglandin F1, 9α,11α,15(S)-trihydroxy-13-trans-prostenoic acid occur in rat testicular tissue and that prostaglandin F2α, 9α, 11α, 15(S)-trihydroxy-5-cis-13-trans-prostadienoic acid and prostaglandin E2, 11α,15(S)-dihydroxy-9-oxo-5-cis-13-trans-prostadienoic acid may be the primary species of this tissue. Prostaglandin B1, 15(S)-hydroxy-9-oxo-8(12),13-trans-prostadienoic acid and prostaglandin B2, 15(S)-hydroxy-9-oxo-5-cis,8(12),13-trans-prostatrienoic acid also were detected, and some evidence was obtained for the presence of prostaglandin metabolites.

Immunochemical localization of parathyroid hormone in cancer tissue from patients with ectopic hyperparathyroidism.

Abstract: Immunoreactive parathyroid hormone (PTH) in nonparathyroid malignant tumors associated with hypercalcemia and hypophosphatemia in the absence of demonstrable bone metastases was determined by radioimmunoassay and immunofluorescent techniques. Six of seven tumors contained material with immunological cross-reactivity to bovine PTH by radioimmunoassay and immunofluorescence. The intensity of the immunofluorescent stain varied considerably in the different tumors. From 15 to 90% of neoplastic cells were stained specifically with fluorescein-labeled anti-PTH. In contrast, normal parathyroid glands and parathyroid adenomas showed uniform distribution of immunofluorescence in all parenchymal cells. In one malignant tumor, PTH was localized also by immunoautoradiography. In every case PTH was detected only in the cytoplasm of parenchymal cells. One patient lacked detectable PTH in his tumor, yet showed regression of the hypercalcemia to normal values after removal of large masses of neoplastic tissue and recurrence of hypercalcemia when new growth occurred. Dilutional radioimmunoassay curves of nonparathyroid malignant tumors were in most cases different from those obtained with extracts of normal parathyroid glands and parathyroid adenomas. Although both nonparathyroid neoplasmas and parathyroid extracts demonstrated immunoheterogeneity by gel filtration, greater heterogeneity was found in nonparathyroid malignant tumors. In those tumors in which immunological cross-reactivity to PTH was detected, the capability of secreting PTH may be restricted to derepressed cell clones amidst other neoplastic cells, whereas the greater heterogeneity of ectopic PTH may reflect hormone cleavage by proteolytic enzymes in the tumor that is less specific than the Pro-PTH cleaving enzyme in the parathyroids.