Showing papers by "Oklahoma State University–Stillwater published in 1984"
TL;DR: In a feeding trial involving newborn dairy calves supplementation of the diet with the more bile resistant strain of Lactobacillus acidophilus caused greater increases of numbers of facultative lactobabilli in the upper small intestines than did the strain exhibiting lower resistance to bile.
450 citations
TL;DR: On confirme l'hypothese selon laquelle la variation de l'intensite de la predation and the competition pour l'alimentation sont responsables of l'importance de l'savantage quant a la survie des jeunes de grandes dimensions.
Abstract: On confirme l'hypothese selon laquelle la variation de l'intensite de la predation et la competition pour l'alimentation sont responsables de l'importance de l'avantage quant a la survie des jeunes de grandes dimensions. Implications evolutives de ces resultats
260 citations
239 citations
175 citations
TL;DR: It is proposed that B. asper myotoxin causes cell injury by disrupting the integrity of skeletal muscle plasma membrane and that myotoxicity is at least partially due to the phospholipase A activity of the toxin.
162 citations
150 citations
TL;DR: Breath hydrogen production was used as a measure of lactose malabsorption in human test subjects following the consumption of both heated and unheated cultured yogurt, indicating that lactose hydrolysis was improved in the small intestine of the individuals consuming the unheating cultured yogurt.
142 citations
TL;DR: It is proposed that the myotoxin induces myonecrosis by first altering the integrity of the plasma membrane, thereby increasing the permeability to calcium, other ions, and molecules which leads to death of the cell.
132 citations
TL;DR: In this paper, the authors analyzed the disordering and flow processes occurring beyond the intrinsic elastic limit of the bcc crystal and showed that a simple linear shear orients and disorders these crystals by forcing (110) planes to stack normal to the shear gradient and to slide relative to each other with a 111g direction parallel to the solvent flow.
Abstract: Highly charged submicrometer plastic spheres suspended in water at low ionic strength will order spontaneously into bcc crystals or polycrystals. A simple linear shear orients and disorders these crystals by forcing (110) planes to stack normal to the shear gradient and to slide relative to each other with a 111g direction parallel to the solvent flow. In this paper we analyze in detail the disordering and flow processes occurring beyond the intrinsic elastic limit of the bcc crystal. We are led to a model in which the flow of a colloidal crystal is interpreted as a fundamentally different process from that found in atomic crystals. In the colloidal crystal the coupling of particle motion to the background fluid forces a homogeneous flow, where every layer is in motion relative to its neighboring layers. In contrast, the plastic flow in an atomic solid is defect mediated flow. At the lowest applied stress, the local bcc order in the colloidal crystal exhibits shear strains both parallel and perpendicular to the direction of the applied stress. The magnitude of these deformations is estimated using the configurational energy for bcc and distorted bcc crystals, assuming a screened Coulomb pair interaction between colloidal particles. As the applied stress is increased, the intrinsic elastic limit of the crystal is exceeded and the crystal begins to flow with adjacent layers executing an oscillatory path governed by the balance of viscous and screened Coulomb forces. The path takes the structure from the ${\mathrm{bcc}}_{1}$ and ${\mathrm{bcc}}_{2}$ twins observed at zero shear to a distorted two-dimensional hcp structure at moderate shear rates, with a loss of interlayer registration as the shear is increased. This theoretical model is consistent with other experimental observations, as well.
123 citations
TL;DR: The newly-formulated extractant and procedure yielded the greatest amount of ATP from soil when compared with the 12 best methods suggested by previous studies.
Abstract: An extraction mixture comprised of 0.67 m H3PO4, 2 m urea, 20% DMSO, 1.8 mg of adenosine, 20 mM EDTA, and 1% Zwittergent 3,10 and a procedure to extract ATP from soil have been developed. The reagents and method were tested on six different Oklahoma soils and yielded a recovery of 99% of the ATP from added Escherichia coli cells. The extraction mixture was designed to minimize interference from soil-derived materials. The phosphoric acid provides acid to extract ATP and to inactivate proteins, and phosphate to saturate phosphate-binding sites. It also complexes or precipitates metal ions. The EDTA chelates metal ions, prevents inhibition of luciferase, and aids lysis of bacterial cells. The adenosine serves to saturate ATP binding-sites. Urea denatures proteins and prevents hydrogen bonding of the released ATP. DMSO, the Polytron treatment, and Zwittergent 3,10 remove cells from surfaces and lyse them. An internal standard of E. coli cells is used to determine efficiency of extraction and assay. When compared with the 12 best methods suggested by previous studies, the newly-formulated extractant and procedure yielded the greatest amount of ATP from soil.
114 citations
TL;DR: The sporadic occurrence of the parasite in domestic cats and the uniform!y fatal syndrome it produces suggest that domestic cats are accidental hosts for this organism.
Abstract: Cytauxzoon feiis was reported first in the United States from domestic cats from Missouri (Wagner, 1975, J. Am. Vet. Med. Assoc. 167: 874; Wagner, 1976, J. Am. Vet. Med. Assoc. 168: 585-588). Since that time there have been reports of the parasite from Texas (Bendele et a!., 1976, Southwest Vet. 29: 244-246), Louisiana (Hauck et a!., 1982, J. Am. Vet. Med. Assoc. 180: 1472-1474) and many other locations in the U.S. (Kier et a!., 1979, Mo. Vet. 29: 15-18). The sporadic occurrence of the parasite in domestic cats and the uniform!y fatal syndrome it produces suggest that domestic cats are accidental hosts for this organism. A recent study indicated that 60% of 20 free-ranging bobcats from Oklahoma harbored an intraerythrocytic piroplasm that was morphologically indistinguishable from C. felis (Glenn et a!., 1982, J. Am. Vet. Med. Assoc. 181: 1251-1253). Blood from these naturally infected bobcats subinoculated intrapenitoneally into domestic cats did not, however, cause fatal cytauxzoonosis. Instead a persistent erythroparasitemia developed, but the cats remained asym ptomatic. Experimental infections of bobcats induced by inoculation of tissues and blood collected from domestic cats in the final stages of the fatal disease has, however, shown that bobcats are susceptible to both a fatal and nonfatal form of the disease (Kier et a!., 1982, Am. J. Vet. Res. 43: 102-105; Glenn et a!., 1983, J. Am. Vet. Med. Assoc. 183: 1155-1158). To date, the bobcat has not
TL;DR: In this paper, the authors developed a taxonomy of high-, medium-, and low-status residential areas (neighborhoods) in Dallas, Texas, which formed the basis of several crosstabulations in which the relative frequency of aggravated assaults was the dependent variable.
Abstract: Relations between human beings and the physical environment have been the foci of research and speculation for at least two millennia. One such focus has dealt with the relationships between climate and crime. This paper develops four hypotheses concerning the interaction between violent behavior and the thermal environment. These hypotheses relate to the structural density of local areas, alcohol consumption across the city, calendar effects, and neighborhood context. We developed a taxonomy of high-, medium-, and low-status residential areas (“neighborhoods”) in Dallas, Texas. These groupings formed the basis of several crosstabulations in which the relative frequency of aggravated assaults was the dependent variable. Neighborhood types differed markedly in the amplitude of their summer peaking of assaults, low-status neighborhoods having a peak not amenable to explanation entirely on the basis of month length or number of weekend days in the months. Assaults directly linked to alcohol sales es...
TL;DR: This paper provides a survey and evaluation of static flowshop scheduling rules and suggests which of the popular scheduling rules hold promise for application to practical flowshop problems.
Abstract: This paper provides a survey and evaluation of static flowshop scheduling rules. A total of sixteen scheduling heuristics, including several revisions and combinations of previously reported methods, are summarized. These scheduling rules are evaluated using a discrete event simulation model. The results for the simulation model are analysed using both statistical and nonstatistical methods. The results from the study suggest which of the popular scheduling rules hold promise for application to practical flowshop problems.
TL;DR: Silverleaf nightshade (Solanum elaeagnifolium) is a perennial weed that has become increasingly troublesome over the past several decades because of extensive use of soil-applied herbicides.
Abstract: Silverleaf nightshade (Solanum elaeagnifolium) is a perennial weed that has become increasingly troublesome over the past several decades. Extensive use of soil-applied herbicides, accompanied by a reduction in annual weed competition and reduced tillage, have contributed to its spread and establishment as a serious pest. Crop plants are affected directly via competition and allelopathy or indirectly as the nightshade plants serve as hosts for destructive phytophagous insects or fungal pathogens. Probably native to the southwestern United States and northern Mexico,S. elaeagnifolium is now found in many semiarid regions of the world. Plants were used by the Pima, Kiowa and Navajo Indians in the preparation of food and in the tanning of leather. Containing the toxic glycoalkaloids solanine and solasonine, plants can cause livestock poisonings. The fruits, however, are a source of solasodine, which is used in the commercial manufacture of steroidal hormones.
TL;DR: Paraffin-coated polystyrene capsules, the same as used for commercial ultrasonic transmitters, were surgically implanted into the abdominal cavity of adult channel catfish Ictalurus punctatus, and surgical implantation of transmitters had not increased mortality or decreased growth compared to fish without implants.
Abstract: Paraffin-coated polystyrene capsules, the same as used for commercial ultrasonic transmitters, were surgically implanted into the abdominal cavity of adult channel catfish Ictalurus punctatus. Capsules had a weight in water equal to either 1% or 2% of the fish's body weight. After an average 112 days from surgery, surgical implantation of transmitters had not increased mortality or decreased growth compared to fish without implants. However, 25 of 35 fish with implants had lost their capsules; the loss rate was greater for the capsules that were 2% of body weight (16 of 18 lost) than for the capsules that were 1% of the body weight (9 of 17). Of the 10 capsules retained, five were in the abdominal cavity, four were in the intestinal lumen, and one was enveloped in a mesentery. Loss of surgical implants of dummy transmitter capsules involved encapsulation, adhesive peritonitis, and, in some cases at least, the formation of an accessory or adventitious loop of intestine that grew about the encapsul...
TL;DR: Polyvalent (Crotalidae) antivenin was tested for its ability to neutralize the hemorrhagic activity of two crotaline venoms when mixed with them prior to injection and results show that both methods are useful for quantitating hemorrhage induced by Crotalus viridis viridis andCrotalus atrox venoms.
TL;DR: The Borrego Springs shear-zone section of the Eastern Peninsular Ranges Mylonite Zone (EPRMZ) contains unequivocal evidence for ductile shearing with an east-over-west sense of movement as discussed by the authors.
Abstract: The Borrego Springs shear-zone section of the Eastern Peninsular Ranges Mylonite Zone (EPRMZ) contains unequivocal evidence for ductile shearing with an east-over-west sense of movement. Field evidence includes the presence of S and C planes and shear bands. All lines of microstructural evidence are internally consistent and support the field observations. It appears that the data are compatible only with post–mid-Cretaceous west-directed thrusting on the EPRMZ.
TL;DR: The Mehlich III and ammonium bicarbonate-DTPA multi-element soil extraction solutions offer increased convenience in soil testing laboratory operations as mentioned in this paper, and they can be used in a variety of applications.
Abstract: Multi‐element soil extraction solutions offer increased convenience in soil testing laboratory operations. The recently developed Mehlich III and ammonium bicarbonate‐DTPA multi‐element extraction ...
TL;DR: The 12-year-old child falls far short of an adult rate of production but is learning a similar set of connectivity forms, and developmental progress takes the form of increasing use of the same conjuncts, plus additional logical relations and an increasing repertoire of lexical items per relation.
Abstract: Natural language samples of 114 children aged 6 to 12 years are analysed for instances of discourse connectivity via adverbial conjuncts and disjuncts. Conjunct use is just emerging at 6 and is limited to the encoding of a subset of possible logical relations with only one lexical item per relation (transitional now, inferential then, result so and concessive though). Developmental progress takes the form of increasing use of the same conjuncts, plus additional logical relations and an increasing repertoire of lexical items per relation. Disjunct use is rare at all ages and largely limited to really and probably. Developmental interactions between form, content and use (discourse context) are probed. The 12-year-old child falls far short of an adult rate of production but is learning a similar set of connectivity forms.
TL;DR: A straight-line relationship was found between the time at peak maximum and the rate coefficient in computer-simulated curves and provided a way to estimate a value for the rate coefficients of the L -ascorbic acid/dichromate reaction which agreed with the one obtained from batch kinetic determinations.
TL;DR: It is proposed that impairment of regeneration after injection of crude venom is a consequence of diminished blood supply to some areas of the muscle.
TL;DR: In this paper, a generalized equation of state (EOS) can be used in a reservoir simulator to calculate the phase equilibria necessary for the prediction of fluid compositions, densities, and viscosities during a displacement process.
Abstract: Numerical simulation of miscible EOR processes requires calculation of the phase equilibria that exist between solvent and oil over the entire solvent/oil composition range. One calculation approach is to tabulate K-values from experimental data and allow the simulator to access the table when necessary. This approach can lead to erroneous conclusions for CO/sub 2/ miscible processes if there are insufficient tabulated phase equilibrium data to cover all possible compositions, in particular those cases where three phases exist at some point in the displacement. This paper presents a different approach to the problem. If a generalized equation of state (EOS) can match experimental data, then it can be used in a reservoir simulator to calculate the phase equilibria necessary for the prediction of fluid compositions, densities, and viscosities during a displacement process. Previous work has shown how a generalized Redlich-Kwong equation can be used to calculate typical hydrocarbon phase behavior relationships that exist in condensate and black oil reservoir systems. The equation parameters have been modified further for use in hydrocarbon/CO/sub 2/ calculations over a wide range of CO/sub 2/ concentrations. Appropriate mixing rules for description of the phase equilibria in CO/sub 2//hydrocarbon systems have been developed. Experimental binary vapor/liquid equilibriummore » (VLE) data have been used to evaluate the constants in the EOS for pure CO/sub 2/ as well as interaction terms used within the mixing rules. Predictions of phase equilibria then have been made and compared with experimental data for a synthetic multicomponent hydrocarbon/CO/sub 2/ system and a crude oil/CO/sub 2/ system.« less
TL;DR: It is known that the Riemann hypothesis implies for all k ≥ 0 (see Ramachandra [2] and Heath-Brown [1]), but there is not even a conjectural value of ck for any other k as mentioned in this paper.
Abstract: LetIt is conjectured that for any k,for some constant ck. It is well known that (2) holds for k = 0, 1 and 2 with c0 = 1, C1 = 1, and c2 = (2π2)-1, but there is not even a conjectural value of ck for any other k. However, it is known that the Riemann hypothesis impliesfor all k ≥ 0 (see Ramachandra [2] and Heath-Brown [1]).
TL;DR: In this paper, the experimental parameters which affect catalytic activity and their mechanisms of action are presented, as well as an analysis of experimental parameters and their mechanism of action for polymeric phase transfer catalysts.
Abstract: Polymer-supported phase transfer catalysts are insoluble polymers having covalently bound functional groups active as catalysts for reactions between anions and neutral organic substrates. The active functional groups may be quaternary ammonium or phosphonium ions, crown ethers, cryptands, grafted poly(ethylene glycols), or analogues of dipolar aprotic solvents. The polymer most often used is polystyrene, but other synthetic polymers, silica gel, and alumina have been used also. The reactions are carried out in triphase mixtures of organic liquid, solid or aqueous inorganic salt; and solid catalyst. The chemical reactions take place within the polymer matrix or on the polymer surface. With heterogeneous catalysts the reaction rates may be limited by mass transfer of reactants to the catalyst surface, intraparticle diffusion of reactants to the active sites, or intrinsic reactivity at the active sites. An analysis of the experimental parameters which affect catalytic activity and their mechanisms of action is presented.
TL;DR: By studying the effects of kinematic parameters on the general 3R robots, the optimum regional structure and the optimum orientational structure are arrived in this paper.
TL;DR: The conclusions reached in this article are that evaluators cannot abandon significance tests, but should use and interpret them differently than in conventional social science research.
Abstract: Significance tests have certain normative implications that are not commonly recognized and present serious complications for evaluation research. One of the conclusions reached in this article is that evaluators often make normative decisions, albeit unintentionally, when they use the traditional .05 significance level in studies with small numbers of cases. Another conclusion, however, is that evaluators cannot abandon significance tests, but should use and interpret them differently than in conventional social science research.
TL;DR: Findings suggest that basophils are involved in bovine immunity to ticks as has been established in the guinea pig model.
TL;DR: In this paper, the energy transfer from Eu,Mn to Mn is shown to occur in RbMg${\mathrm{F}}_{3}$:Eu,mn crystals.
Abstract: Energy transfer from ${\mathrm{Eu}}^{2+}$ to ${\mathrm{Mn}}^{2+}$ ions is shown to occur in RbMg${\mathrm{F}}_{3}$:Eu,Mn crystals. Emission and excitation spectra indicate that the energy transfer is a resonant process between the ${\mathrm{Eu}}^{2+}$ $^{6}P_{\frac{7}{2}}\ensuremath{\rightarrow}^{8}S_{\frac{7}{2}}$ emission and the ${\mathrm{Mn}}^{2+}^{6}A_{1g}\ensuremath{\rightarrow}^{4}T_{2g}^{2}$ absorption levels. The energy transfer is so efficient, even at low dopant concentrations of \ensuremath{\sim}2000 ppm, that at these low concentrations energy transfer must occur between copious ${\mathrm{Eu}}^{2+}$-${\mathrm{Mn}}^{2+}$ close pairs. These ${\mathrm{Eu}}^{2+}$-${\mathrm{Mn}}^{2+}$ pairs from preferentially in the lattice. For higher ${\mathrm{Mn}}^{2+}$ concentrations the energy transfer occurs not only among ${\mathrm{Eu}}^{2+}$-${\mathrm{Mn}}^{2+}$ pairs, but also between ${\mathrm{Eu}}^{2+}$and ${\mathrm{Mn}}^{2+}$ ions.
TL;DR: In this paper, a questionnaire was completed by 230 parents of patients from three quite different pediatric practices in the south-central United States and the results indicated that age, educational level, and income were associated with level of child development knowledge.
Abstract: Parents' general knowledge of child development and the demographic factors associated with that knowledge were studied. A questionnaire was completed by 230 parents of patients from three quite different pediatric practices in the south-central United States. Chi square analysis was used as the major statistical technique. Results indicated that age, educational level, and income were associated with level of child development knowledge. Parents reported the sources and educational techniques that were most helpful to them in the past and present. The majority (81%) of the questions that parents wished to direct to pediatricians, given sufficient time, were concerned with psycho- social issues. It appears that the pediatric practice is a logical means of providing information to parents about their children's health concerns, both behavioral and physical. These results emphasize the importance of training pediatricians in behavioral issues and in improving their communication skills. The results are presented to help pediatricians select the anticipatory guidance and educational techniques that might be provided to parents through the pediatric practice.