Showing papers by "University of North Texas published in 1976"
TL;DR: A marked increase in the levels of NAD is observed in 3T3 cells, but not in SVT2 cells, at cell densities just prior to where 3T 3 cells enter density-dependent inhibition of growth, correlated with the cessation of DNA synthesis.
204 citations
98 citations
TL;DR: The vertical stratification sampler recovered significantly greater populations in the surface 20 cm, but not in the total 40 cm, than a modified Hess sq.
Abstract: Vertical stratification samplers were developed for sampling the grave-sand substrate of a Brazos River, Texas riffle Fifteen of 25 species recovered, occurred below 10 cm Mean percentages of total organisms recovered were 664%, 20%, 61% and 75% per 10 cm level, respectively, from the surface down Dominant insects were Neochoroterpes mexicanas naiads and chironomid, Simulium, Cheumatopsyche and Stenelmis larvae Seasonal population peaks of these five groups in the top 10 cm correspond with observed emergence peaks The smaller size classes were generally predominant in the 0–10 cm level Larvae of Stenelmis were the most evenly distributed among the various 10 cm levels in all size classes A movement of Cheumatopsyche and Neochoroterpes to lower levels was observed following a large flood, suggesting an escape response to increased silt load and scouring
85 citations
TL;DR: This study indicates that interactions of the C7-methylene bridge with the bonds of theC2C3 ethylene bridge are responsible for the nonequivalence of Jexo,exo and Jendo,endo in norbornanes, and that in Norbornenes interaction of the olefin functionality with bonds ofThe ethylene Bridge is responsible for bridging Jexi, exo back fortuitously close to Jenda,endo.
70 citations
TL;DR: In this article, the authors state that teacher morale is too often placed at the bottom of the list of administrators' priorities, and that teachers' morale has a direct reflection on the operation of the school.
Abstract: It is a well-known fact that teacher morale has a direct reflection on the operation of the school. Yet, the authors state, teacher morale is too often placed at the bottom of the list of administr...
55 citations
TL;DR: Electrophoretic patterns of 14 proteins encoded by 15 genetic loci were examined from 35 populations of seven species of North American blackbirds and revealed a genetic basis for considering the seven species as members of two groups previously established from morphological evidence.
Abstract: 1 1 Electrophoretic patterns of 14 proteins encoded by 15 genetic loci were examined from 35 populations of seven species of North American blackbirds, family Icteridae 2 2 Analysis of allelic variation revealed a genetic basis for considering the seven species as members of two groups previously established from morphological evidence These are the Agelaiine group, which includes two species of meadowlarks, genus Sturnella, and the Red-winged Blackbird, Agelaius phoeniceus, and the Quiscaline group which includes the Brewer's Blackbird, Euphagus cyanocephalus, and two species of grackles, Cassidix mexicana and Quisculus quiscula The more primitive Brownheaded Cowbird, Molothrus ater, was found to be most similar to members of the Quiscaline group 3 3 A phylogeny of the taxa is presented including divergence times for the seven species Speciation of the forms appears to have been within the last 160,000 years, with a major portion of the divergence occurring during the Pleistocene glaciation
47 citations
TL;DR: The enzyme was shown to be homogeneous by a variety of criteria and was found to be a dimer composed of two apparently identical catalytic and physical properties and their interconvertible nature suggest that they do not represent true isozymes.
42 citations
TL;DR: The life cycle was multivoltine, with 3 relatively distinct generations, and nymphs underwent 16 and 19 instars in the overwintering and combined summer generations, respectively, and could be sexed beginning in the 7th.
Abstract: Studies were conducted from 1971–73. Emergence occurred from late afternoon to near sunset March through November. Life span after emergence was less than 24 h, and both subimagoes and imagoes exhibited a seasonal variation in total body length. Mating occurs in flight, with ♂ swarms occurring over land during the morning. Females fly upstream, alight on the water and extrude all eggs at once. A seasonal-generation periodicity in fecundity was noted. Eggs are barrel shaped, .18 mm long × .12 mm wide, have elaborate chorionic sculpturing, and peg-like attachment structures. Incubation at 25± 1°C required 13–15 days. First instar nymphs measured .45 mm total body length, had 5-segment cerci and antennae and displayed no gills. The life cycle was multivoltine, with 3 relatively distinct generations. Nymphs underwent 16 and 19 instars in the overwintering and combined summer generations, respectively, and could be sexed beginning in the 7th. Sex ratios of 1264 nymphs and 549 subimagoes were 1:1. Nymphs fed on detritus (90%) and algae, with seasonal variation in varieties and percentages. Mean standing crop on biweekly (or monthly) sampling dates was 880 individuals/m2. Mean cohort turnover ratio, mean annual turnover ratio and total annual production (dry wt) were 5.1, 15.4, and 247.9 mg/m2, respectively for the 3 generations.
42 citations
TL;DR: This study has utilized data from 22 genetic loci from 25 populations of pocket gophers including all 5 species of the genus Geomys to compare genetic variation and patterns of geographic distribution, degree of isolation, protein specificity, adaptive strategy, and speciation in the genus.
Abstract: With the recent development in the use of electrophoresis, there has been a surge of interest in studying genetic variation in populations and genetic differentiation of vertebrate species (Selander and Johnson, 1973). It has become increasingly obvious that one can correlate patterns of genetic variation with geographic distribution, strategies of adaptation, and the interrelationships of enzyme polymorphism and metabolism (Selander and Kaufman, 1973; Johnson, 1974; Nevo et al., 1974). Specifically, the following should be investigated to determine if correlations exist between protein variation and the biology of the organism: (1) patterns of protein variation and geographic distribution; (2) patterns of protein variation and substrate specificity of the protein; (3) patterns of protein variation and adaptive strategy; and (4) patterns of genic divergence, speciation, and evolutionary time. To test for such correlations, we chose to investigate genic variation in a genus of fossorial rodents, Geomys. At present, four species of the Geomys complex of pocket gophers inhabit a large area of the central and southeastern United States, while one species, G. tropicalis, is found only in a small area in southern Tamaulipas, Mexico (Hall and Kelson, 1959). The ranges of the five species reflect past distribution with isolation of three of the forms into disjunct populations. Geomys bursarius has the most extensive range from the western great plains, south to the Texas coast, and north into Canada. Geomys personatus is restricted to the Texas Rio Grande valley north to the Rio Grande River and is contiguous with G. bursarius from Corpus Christi to the San Antonio River. Geomys arenarius is isolated in extreme western Texas and south-central New Mexico, and G. pinetis is isolated in Alabama, Georgia, and Florida. The evolution of the genus Geomys is well-documented, based on fossil evidence. According to Russell (1968), Geomys personatus and G. arenarius probably diverged from the southern and western portions of populations of G. bursarius during Wisconsin or Recent time. Geomys pinetis and G. bursarius were separated and diverged from the ancestral stock during the midIllinoian glacial period, with post-glacial habitats of the Mississippi Valley preventing reestablishment of the forms in that region. Chromosomal evolution in the genus Geomys has been characterized by Davis et al. (1971), Kim (1972), and Baker et al. (1973). More recently, Selander et al. (1975) compared interspecific chromosomal differences and genic divergence in four species of Geomys, and although some of their data are similar to ours, they studied only four of the five extant species. In this study we have utilized data from 22 genetic loci from 25 populations of pocket gophers including all 5 species of the genus. In the process we have attempted to compare genetic variation and patterns of geographic distribution, degree of isolation, protein specificity, adaptive strategy, and speciation in the genus Geomys.
41 citations
TL;DR: In this article, the authors compare theoretical predictions of the binary-encounter, semiclassical, and plane-wave Born approximations (PWBA) with the measured x-ray production cross sections.
Abstract: $K$-shell x-ray production corss sections for $^{12}\mathrm{C}$, $^{14}\mathrm{N}$, and $^{16}\mathrm{O}$ ions on thin targets of Ni, Rb, Ag, and Sb were measured over the incident-ion energy range of 0.4-2.4 MeV/amu. Comparisons to theoretical predictions of the binary-encounter, semiclassical, and plane-wave Born approximations (PWBA) show that these theories overpredict the magnitude of the measured cross sections. The PWBA calculations with perturbation corrections for binding energy and Coulomb deflection effects included are in better agreement with the measured data for $\frac{E}{M}l1.2$ MeV/amu. Comparison of the data to the perturbed PWBA calculations which also include corrections of electron polarization effects in the case of $^{12}\mathrm{C}$ on Ni gives good agreement between these theoretical estimates and the measured $K$-shell x-ray production cross sections.
31 citations
TL;DR: Ventilation and oxygen consumption rates of green sunfish exposed to bentonite clay suspensions were measured at 5, 15, 25, and 35 C as discussed by the authors, showing that increased ventilation rates under highly turbid conditions are a means of compensating for reduced respiratory efficiency and a strategy for maintaining a constant oxygen uptake.
Abstract: Ventilation and oxygen consumption rates of green sunfish exposed to bentonite clay suspensions were measured at 5, 15, 25, and 35 C. Ventilation rates were not affected by bentonite clay suspensions below 2,125 FTU (Formazin Turbidity Units) at 5 C, 1,012 FTU at 15 C, and 898 FTU at 25 C. At turbidity levels exceeding 1,012 FTU at 15 C and 898 FTU at 25 C ventilation rates increased 50-70%. Tests were inconclusive at 35 C due to high mortality. Oxygen consumption rates were not affected by turbid suspensions of up to 3,500 FTU at any of the four temperatures. Evidence suggests that increased ventilation rates under highly turbid conditions are a means of compensating for reduced respiratory efficiency and a strategy for maintaining a constant oxygen uptake. The costs of increased ventilation rates were probably met by a reduction in activity.
TL;DR: These studies indicate the prerequisite of dimer formation for catalytic activity but the independent action of the catalytic centers of the dimer.
Abstract: Dimeric phosphoglucose isomerase from rabbit muscle was immobilized by reaction with cyanogen-bromide-activated Sepharose 4B. The catalytic parameters and stability properties of the free and matrix-bound isomerases were essentially identical. Total monomerisation of the matrix-bound enzyme was achieved with 8 M urea as determined by a study in which one subunit was labelled with iodo[14C]acetate and the other with the 3H-labelled reagent. Although matrixbound monomers were devoid of isomerase activity, they were still capable of binding the substrate. Matrix-bound monomers exhibited the ability to redimerize with soluble isomerase subunits from either rabbit or human yielding catalytically active dimers. Yeast isomerase monomers, in contrast, did not yield active hybrids with the rabbit monomers. Furthermore, soluble subunits, which had been inactivated with pyridoxal 5′-phosphate were also capable of hybridizing with and inducing catalytic activity in the matrix-bound monomers. These studies indicate the prerequisite of dimer formation for catalytic activity but the independent action of the catalytic centers of the dimer.
TL;DR: This paper applied facial screening to a 7-year-old schizophrenic boy during a language training class and found that facial screening suppressed hand clapping but had no effect on correct verbal responses.
TL;DR: The correlation coefficient (r) for AHH and SAH co-inducibility was −0.08, indicating no correlation and suggesting the absence of association between the two enzymes in man.
Abstract: Aryl hydrocarbon hydroxylase and 16alpha-hydroxylase were examined in intact, cultured human lymphocytes. The two microsomal mixed-function oxygenases had different pH optima and showed competitive inhibition for enzyme induction and activity. Population distributions were lognormal for both enzymes, giving apparent evidence for polygenic control. Induced levels of AHH were slightly higher among first-order relatives of lung or colon cancer patients than in the control group. The correlation coefficient (r) for AHH and SAH coinducibility was -0.08, indicating no correlation and suggesting the absence of association between the two enzymes in man.
TL;DR: A novel technique is described for assay of aryl hydrocarbon hydroxylase in cultured human lymphocytes, the sensitivity is equal to that of previous methods, but this method requires fewer manipulations.
TL;DR: This study was designed to determine if intelligibility scores on a standard intelligibility measure for children, whereby the words on the test was modified by 35% FS/TC, would show improvement from a pre- to a post-testing session.
Abstract: Several electromechanical aids to education for hearing-impaired children have been studied One method that has received minimal attention is that of frequency-shifted/time-compressed (FS/TC) speech This study was designed to determine if intelligibility scores on a standard intelligibility measure for children, whereby the words on the test were modified by 35% FS/TC, would show improvement from a pre- to a post-testing session Nine hearing-impaired children were presented a 0 and 35% FS/TC speech pre-test, then trained for 15 days using 35% FS/TC speech signals, and subsequently were presented a 0 and 35% FS/TC speech post-test A second group of 9 hearing-impaired children were presented similar pre- and post-tests, but were trained under a 0% FS/TC speech condition The group trained under the 35% FS/TC speech condition showed score gains from the pre- to post-test session, whereas the 0% FS/TC speech group showed essentially no gains from the pre- to the post-test session The potential applicatio
TL;DR: It is postulated that the kinetic parameters of the enzyme are the results of its function, that of generating glucose 6-phosphate primarily for glycogen synthesis.
TL;DR: Seeds from Sophora secundiflora were extracted into three major fractions: lipids, alkaloids, and amino acids, and both the amino acid fraction and the alkaloid fractions caused minor pharmacological disorder when injected into rats, but when both fractions were simultaneously administered, they were lethal.
TL;DR: The genetic structure of 21 populations of P. pectoralis has been analyzed through electrophoretically demonstrable variation in proteins encoded by 17 to 21 structural loci and a wide range in levels of heterozygosity and genetic similarity was exhibited.
Abstract: The genetic structure of 21 populations of P. pectoralis has been analyzed through electrophoretically demonstrable variation in proteins encoded by 17 to 21 structural loci. A wide range in levels of heterozygosity, 0.0 to 0.178, with a mean of 0.05, and levels of genetic similarity, 0.691 to 0.991, with a mean of 0.829, were exhibited among populations of P. pectoralis . This variation in levels of heterozygosity and genetic similarity is thought to be the result of colonization and, hence, genetic contribution from populations from three Pleistocene refugia with differentiated gene pools. With the removal of the primary isolation barriers, gene exchange between populations derived from different refugia have produced populations with high levels of heterozygosity. Because individual populations of P. pectoralis have received their genetic makeup from one to three different gene pools, they exhibit lower levels of genetic similarity than observed among most conspecific populations of this genus.
TL;DR: In this article, ionization cross sections are calculated from atomic $K$-shell fluorescence yields and compared to the theoretical predictions of the plane-wave Born approximation including binding energy, Coulomb deflection, and relativistic corrections.
Abstract: Absolute $K$-shell x-ray production cross sections for thin Ca, Sc, Ti, V, Fe, Ni, Cu, Zn, Ge, Rb, Sr, Y, Zr, and Pd targets have been measured for incident carbon ions in the energy range from 8 to 36 MeV. Ionization cross sections are calculated from atomic $K$-shell fluorescence yields and compared to the theoretical predictions of the plane-wave Born approximation including binding energy, Coulomb deflection, and relativistic corrections. $\frac{K\ensuremath{\alpha}}{K\ensuremath{\beta}}$ ratios and the shifts in the characteristic $K\ensuremath{\alpha}$ and $K\ensuremath{\beta}$ energies indicate the existence of multiple ionization in the low-$Z$ targets.
TL;DR: A simple method has been developed for the rapid isolation of crystalline glucosephosphate isomerase (EC 5.3.1.9) from rabbit muscle and results in a good recovery of the enzyme with specific activity of approximately 900 units per mg.
TL;DR: In this article, the authors suggest that the needs of inspirations will make you searching for some sources, even from the other people experience, internet, and many books, and suggest to have more inspirations, then.
Abstract: Inevitably, reading is one of the requirements to be undergone. To improve the performance and quality, someone needs to have something new every day. It will suggest you to have more inspirations, then. However, the needs of inspirations will make you searching for some sources. Even from the other people experience, internet, and many books. Books and internet are the recommended media to help you improving your quality and performance.
TL;DR: The vapor phase vacuum ultraviolet absorption spectra of dichlorosilane, dichloromethylsilane and dichlorodimethylsilane are reported for the region from 40 000 to 83 000 cm−1 (250-120 nm) as mentioned in this paper.
TL;DR: In this paper, the spin-tickling proton n.r. study of 13C-carboxyl-endo-1,2,3,4,7,7-hexachloronorbornene-5 carboxylic acid was carried out.
Abstract: A tabulation has been compiled for twenty 13CH coupling constants of various carboxylic acids and includes 2J(C,H), 3J(C,H) and 4J(C,H) values of olefins (both cis and trans); 3J(C,H), 4J(C,H) and 5J(C,H) values of aromatics; 3J(C,H) and 4J(C,H) values of acetylenes; and 2J(C,H) and 3J(C,H) values of rigid aliphatics. This tabulation has been completed in the present study by the spin-tickling proton n.m.r. study of 13C-carboxyl-endo-1,2,3,4,7,7-hexachloronorbornene-5-carboxylic acid, which has established that the 2J(C,H) value is negative and the 3J(C,H) values (both cis and trans) are positive in this system. A plot of these twenty J(C,H) values vs the corresponding J(H,H) values of geometrically equivalent model systems (where there is a proton in place of a carboxyl group) gives a correlation coefficient of 0·975 (with a slope of 0·62), indicating that carbon–proton and proton–proton couplings operate by similar mechanisms throughout this broad series of structural types.
TL;DR: The destructive distillation or pyrolysis of borane 9-borabicyclo[3.3.1]nonane, or dicycloenylborane adducts to vinylsilanes which have been treated with sodium methoxide in methanol gives significant yields of products resulting from protonolysis of the CB bond.
TL;DR: The authors found that liking has a more specific effect on personal disclosure than does knowing, but that liking and knowing do not differ in relative control over impersonal disclosure, and a correlational analysis involving subjects' perceptions of the experimental situation and dependent disclosure measures supported this interpretation.
01 Jun 1976
TL;DR: The design, execution, and assessment of therapeutic interaction and the observed language abilities of the client are reported and case information of a 10-year-old traumatic aphasic girl seen at the North Texas State University Speech and Hearing Center is presented.
TL;DR: Horizontal starch gel electrophoresis revealed five hemoglobin phenotypes in natural populations of the encinal mouse, Peromyscus pectoralis, from northeastern Mexico that were monomorphic for multiple-band phenotypes.
Abstract: Horizontal starch gel electrophoresis revealed five hemoglobin phenotypes in natural populations of the encinal mouse, Peromyscus pectoralis, from northeastern Mexico. Populations of the encinal mouse from Texas, Oklahoma, and northwestern and north central Mexico were monomorphic for multiple-band phenotypes. Analysis of the hemoglobin polymorphism indicates that two loci control this variation.