Showing papers by "University of Arkansas published in 1969"
TL;DR: The rostral connections of the inferior colliculus with areas other than the medial geniculate body indicate that it may function in roles in addition to that of a mass somatomotor reflex center.
Abstract: Projections of the feline inferior colliculus were studied using the Nauta-Laidlaw method to demonstrate degenerating axons. A subtentorial stereotaxic approach was used to avoid corticofugal degeneration. Direct connections from the inferior colliculus to the anterior midline cerebellar cortex were observed. There is a topographical relationship of fibers of the brachium of the inferior colliculus and parabrachial region to the superior colliculus. A definite projection to the superior colliculi including a pathway through its commissure was found from the parabrachial region. A projection exists from the inferior colliculus to the dorsolateral portion of the central gray as far as the pretectum. There is a projection along the medial portion of the superior colliculus to the pretectum. Projections to the midbrain reticular formation, central gray and superior colliculi were substantial. Thalamic projections include a distribution of fibers to the magnocellular and rostral portion of the principal divisions of the medial geniculate body and to the lateral posterior thalamic nucleus. The rostral connections of the inferior colliculus with areas other than the medial geniculate body indicate that it may function in roles in addition to that of a mass somatomotor reflex center. Possible roles of the inferior colliculus in attention, habituation, and integration of corticovisual and auditory impulses are suggested.
124 citations
TL;DR: In this article, it was shown that the expression I =k ⌆ pi In (pi/pi0), wherek is a positive constant, is the unique expression for the information contained in a message which alters the probabilities from thepi0 to thepi.
Abstract: Consider a random experiment whose possible outcomes arez1,z2,...,zn. Let the prior probabilities be p10, ...,pn0, and let the posterior probabilities bep1,...,pn. It is shown that, subject to certain prescribed and intuitively reasonable conditions, the expressionI =k ⌆ pi In (pi/pi0), wherek is a positive constant, is the unique expression for the information contained in a message which alters the probabilities from thepi0 to thepi.
106 citations
TL;DR: This chapter brings together the various aspects of beetle transmission of plant viruses and shows how beetles in the family, Chrysomelidae, commonly called leaf beetles, have been shown to transmit plant viruses.
Abstract: Publisher Summary Although the majority of plant viruses are transmitted by insects with sucking mouthparts, some viruses are transmitted by insects with biting mouthparts. Of the insects with biting mouthparts that transmit viruses, the beetles are the most important vectors. Viruses transmitted by beetles apparently cannot be transmitted by insects with sucking mouthparts. Until recently it has been generally assumed that when a biting insect behaves as a vector, it only does so by carrying infective sap from diseased to healthy plants on its mouthparts. However, when a beetle is an efficient vector and retains virus up to 20 days as the cucumber beetle does with squash mosaic virus, some additional mechanism of transmission probably is involved. This chapter brings together the various aspects of beetle transmission of plant viruses. Viruses transmitted by beetles have many properties in common. Usually, they are relatively stable, develop a high titer in infected plants, can be readily transmitted by manual inoculation, have spherical or polyhedral particles from 25 to 30 mp in diameter, and are highly antigenic. Host ranges and symptoms are usually not correlated with any specific features of the virus particles or with their vectors. The beetle-transmitted viruses can be divided into two groups depending on the length of time the viruses are retained by their vectors. The larger group consists of the viruses that are retained by their vectors for a prolonged period of time. The other group is made up of those viruses that are retained by their vectors for short periods of time, usually 24-48 hours. Only beetles in the family, Chrysomelidae, commonly called leaf beetles, have been shown to transmit plant viruses. All but two of the beetles belong in two subfamilies-Galerucinae (Galerucine leaf beetles) and Halticinste (flea beetles).
79 citations
TL;DR: Anaphase was characterized in both fungi by separation of chromosomes to poles established by the centrioles, and in F. oxysporum anaphase separation of chromosome separation was observed in vivo.
Abstract: Vegetative nuclei of fungi Ceratocystis fagacearum and Fusarium oxysporum were studied both in the living condition with phase-contrast microscopy and after fixation and staining by HCl-Giemsa, aceto-orcein, and acid fuchsin techniques. Nucleoli, chromosomes, centrioles, spindles, and nuclear envelopes were seen in living hyphae of both fungi. The entire division process occurred within an intact nuclear envelope. Spindles were produced between separating daughter centrioles. At metaphase the chromosomes became attached to the spindle at different points. In F. oxysporum the metaphase chromosomes were clear enough to allow counts to be made, and longitudinal splitting of the chromosomes into chromatids was observed. Anaphase was characterized in both fungi by separation of chromosomes to poles established by the centrioles, and in F. oxysporum anaphase separation of chromosomes was observed in vivo. Continued elongation of the spindles further separated the daughter nuclei. Maturing daughter nuclei of both fungi were quite motile; and in C. fagacearum the centriole preceded the bulk of the nucleus during migration. The above observations on living cells were corroborated by observations on fixed and stained material.
78 citations
TL;DR: There is limited information concerning biological availability of individual amino acids in grain and protein concentrates, but amino acid values are rapidly being determined for feeds and lysine availability is determined by fecal and growth analysis.
72 citations
TL;DR: The results indicate that the odor of the species is learned, that the intensity of the odor is important, but that age is not a critical variable in the early learning of thespecies odor in the rat.
Abstract: The odor of rat litter-mates was experimentally modified from 3-10, 11-18, or 22-29 days of age. Acetophenone or ethyl benzoate were used during the experimental period and the natural odor was present during the other two periods. After living in the natural odor colony for another 2 weeks, Ss were compared on duration of time near each olfactory stimulus animal in an eight hour test. Ss preferred the stimulus animal characterized by the experimental odor with which they were reared. Age of exposure was not a significant factor. These results indicate that the odor of the species is learned, that the intensity of the odor is important, but that age is not a critical variable in the early learning of the species odor in the rat.
65 citations
TL;DR: Quantitative studies reveal that the alpha-amylase-catalyzed cleavage of the α- d -(1→4) bonds in starch proceeds with retention of configuration, and a reaction mechanism involving general acid-catalysis by imidazole, and ring distortion to produce an oxycarbonium-ion intermediate, is proposed.
57 citations
TL;DR: In this article, complexes of lanthanides of the type LnCl3-3HMPA have been prepared and characterized by means of analytical, conductivity and infrared spectral studies (HMPA = O = P[N(CH3)2]3).
46 citations
TL;DR: In this paper, the authors presented a 40-item fear survey schedule with five conceptually pure factors accounting for at least 90 per cent of the variance in the variance of the survey schedule.
43 citations
TL;DR: Results show that the hippocampal rudiment, central gray, subthalamus and posterior hypothalamus are intimately involved in mechanisms of neurohypophysial hormones release by determined by milk-ejection, pressor, evoked potential and degeneration techniques.
43 citations
TL;DR: Cytoplasmic inclusions associated with pokeweed mosaic virus (PMV) infection are similar to those which have been reported for other long, flexuous rod-shaped viruses.
TL;DR: In this article, the relationship of fossils to structures and mineral concentrations in most of these concretions illustrates the significance of organic decomposition and the resultant gases in very early diagenesis.
TL;DR: A four-year-old boy with a severe phobia for loud sudden noises was successfully treated with behavior modification utilizing muscle relaxation and in vivo conditioning in six sessions.
TL;DR: The consumer’s demand for better meat products has stimulated extensive research for the production of better poultry items and the influence of energy level, horminization, and protein level on tenderness evaluation and chemical composition of the carcass is compared.
TL;DR: In this article, functions with closed graphs are studied and the authors propose a function with closed graph functions with a closed graph (FFG) for the first time. The American Mathematical Monthly: Vol. 76, No. 8, pp. 930-932
Abstract: (1969). Functions with Closed Graphs. The American Mathematical Monthly: Vol. 76, No. 8, pp. 930-932.
TL;DR: Studies show that when intact rat liver mitochondria are incubated with 74As-inorganic arsenate a new radioactive substance is produced which has been isolated and shown to possess properties that would be expected for a stable low molecular weight arsenate ester.
TL;DR: Counter statements based on recent research are presented for Lieberman's criticisms of earlier work (Truax, 1966).
Abstract: Counter statements based on recent research are presented for Lieberman's criticisms of earlier work (Truax, 1966).
TL;DR: In this article, the critical lengths and the natural frequencies of transverse vibration of vertical pipes having different end constraints are determined by the use of a power series, assuming that the pipes are subjected to a hydrostatic pressure.
Abstract: The critical lengths (or weights) and the natural frequencies of transverse vibration of vertical pipes having different end constraints are determined by the use of a power series. It is assumed that the pipes are subjected to a hydrostatic pressure. Due to gravity, the axial force in a pipe varies linearly along the length of the pipe. The critical lengths are given in a dimensionless form, and the frequencies are presented numerically as a function of the weight-length parameter. The physical interpretations of the results are also given.
TL;DR: In this article, the use of chronoamperometry has been shown to eliminate the need for a stirring apparatus in dissolved oxygen measurement, and increased the sensitivity of the measurement over that found when the electrodes were used in the conventional manner.
TL;DR: Aspergillus sclerotiorum Huber was observed to produce a bright red pigment (Compound A) when grown in mixed culture with a bacterium, Pseudomonas chlororaphis (Guignard & Sauvageau) Bergey et al. as discussed by the authors.
Abstract: Aspergillus sclerotiorum Huber was observed to produce a bright red pigment (Compound A) when grown in mixed culture with a bacterium, Pseudomonas chlororaphis (Guignard & Sauvageau) Bergey et al. ...
TL;DR: In this paper, a time-resolved spectroscopy of the $3.1D and $4.3D levels of helium by electron impact has been studied, and the cross sections for the direct excitation of these levels by 38-, 50-, and 100-eV electron impact are estimated.
Abstract: Excitation of the $3^{1,3}D$ and $4^{1,3}F$ levels of helium by electron impact has been studied by time-resolved spectroscopy of the $3^{1}D\ensuremath{\rightarrow}2^{1}P(\ensuremath{\lambda}6678\AA{})$ and $3^{3}D\ensuremath{\rightarrow}2^{3}P(\ensuremath{\lambda}5876\AA{})$ transitions. (Excitation of the $4^{1}F$ and $4^{3}F$ levels are observed as cascade components under time resolution.) Cross sections are estimated for the direct excitation of these levels by 38-, 50-, and 100-eV electron impact. Excitation of the $4F$ levels by direct electron impact are much larger than predicted by the Born approximation but much smaller than implied by previous experimental measurements. Direct excitation of the $3^{1}D$ and $4^{1}F$ by 100-eV electron impact is in excellent agreement and satisfactory agreement, respectively, with preliminary close-coupling approximation calculations. The collisional transfer $4^{1}P\ensuremath{\rightarrow}4^{3}F$ is much smaller relative to the $4^{1}P\ensuremath{\rightarrow}4^{1}F$ transfer than has previously been suggested.
TL;DR: The 1.287 MeV level (J π = 7 2 − ) in 53Cr was found to be populated in the β-decay of 1.54 min 57Mn.
TL;DR: Six protein fractions reported to be present in the blood serum of the cock were separated by zone electrophoresis on paper using aqueous veronal or borate buffer to find a pre-albumin moving ahead of albumin in the sera of laying hens.
TL;DR: Far-red light alone inhibited first internode elongation as effectively as red light of similar dosage, and the coleoptile tip showed the greatest sensitivity for red light reception in the internode response.
Abstract: Brief, low energy (approximately 400 Kerg cm(-2)) red light interruption of the early dark-growth period of Zea mays L. cv F-M Cross induced inhibition of first internode elongation which was maximal whenever light interruption occurred from 2.5 to 4 days of seedling age. Two-thirds of the maximal inhibition occurred in the tissues constituting the region 0 to 2 mm below the coleoptilar node at time of light treatment. The coleoptile tip showed the greatest sensitivity for red light reception in the internode response. Far-red light exposures following red light treatments reversed the red light effect. However, far-red light alone inhibited first internode elongation as effectively as red light of similar dosage.
TL;DR: In this article, the occurrence of plutonium-244 in the early solar system can be considered as proof that the transuranium elements were synthesized by the r-process in exploding stars (supernovae) and there remained uncertainties concerning the origin of iodine-129 and the interpretation of the isotopic compositions of xenon in meteorites.
Abstract: Plutonium-244 (half-life, 8.2 × 107 years) and iodine-129 (half-life, 1.7 × 107 years) existed in nature during the early history of the solar system. The occurrence of plutonium-244 in the early solar system can be considered as proof that the transuranium elements were synthesized by the r-process in exploding stars (supernovae). There remained, however, uncertainties concerning the origin of iodine-129 and the interpretation of the isotopic compositions of xenon in meteorites.
TL;DR: Radioactive creatine was given parenterally to normal and to dystrophic mice of Bar Harbor Strain 129 before their extensor digitorum longus muscles were removed for study in vitro, finding evidence of an intracellular abnormality in the metabolism of creatine in Dystrophic muscle.
Abstract: SummaryRadioactive creatine was given parenterally to normal and to dystrophic mice of Bar Harbor Strain 129 either 1 hr (short-term 14C-creatine) or 1 week (long-term 14C-creatine) before their extensor digitorum longus muscles were removed for study in vitro. After short-term 14C-creatine and under aerobic conditions, part of the radioactivity was lost more rapidly from dystrophic muscles than from normal muscles; but, under anaerobic conditions, the losses of radioactivity from normal and dystrophic muscles were similar because the rate of loss from normal muscles accelerated. After long-term 14C-creatine and under aerobic conditions, losses of radioactivity from both groups of muscles were small; but, under anaerobic conditions, part of the radioactivity was lost more slowly from dystrophic muscles than from normal muscles. These findings are evidence of an intracellular abnormality in the metabolism of creatine in dystrophic muscle.We are indebted to Mrs. Judy M. Dacus for technical assistance.
TL;DR: After five weeks of training, the combination group had made significantly greater improvements in the AAHPER fitness test and volleyball skill than either of the other groups.
Abstract: The purpose of the study was to determine the effects of different amounts of calisthenics and volleyball in tenth grade physical education classes on the AAHPER fitness test and volleyball skill. Seventy-six boys participated in the following classes: (a) combination of calisthenics and volleyball, (b) calisthenics, and, (c) volleyball. The subjects were tested prior to (T-1), during the third week (T-2) and at the conclusion of the five-week unit (25 class sessions) (T-3). The reliability coefficients were determined by test-retest prior to the unit. The differences among the three groups were determined by a one-way analysis of variance at T-1 and analysis of covariance at T-2 and T-3 (using the T-1 data as the covariates). Whenever there was a significant difference (.05 level) among the groups, Duncan's Multiple Range was used to determine which groups were significantly different from each other. After five weeks of training, the combination group had made significantly greater improvements...
TL;DR: In this article, the effect of changes in solvent composition and electrolyte concentration on the solvating properties of water and N-methylacetamide in aqueous solutions of AlCl3, Al(ClO4)3, ClO4), Al(NO3), NO3−1, ThNO3−4, Mg+2 > Li+1, and LiClO 4 was investigated.
TL;DR: Creatine entry into isolated extensor digitorum longus muscles of normal and of dystrophic mice was studied with the aid of creatine-14C as a tracer to find the creatine entry process in mouse muscle was found to differ from that of rat muscle by having a major nonsaturable component.
Abstract: SummaryCreatine entry into isolated extensor digitorum longus muscles of normal and of dystrophic mice was studied with the aid of creatine-14C as a tracer. The creatine entry process in mouse muscle was found to differ from that of rat muscle by having a major nonsaturable component.At all external creatine concentrations, entry of creatine into dystrophic muscles exceeded entry into normal muscles, even after correcting for a greatly expanded inulin space in dystrophic muscles. This finding is inconsistent with the hypothesis of inhibited creatine entry in vivo, leaving accelerated loss of creatine to explain the low creatine content of skeletal muscle of dystrophic mice.
TL;DR: In this paper, a new 0.40 ± 0.05 sec activity with a β end point energy of 7·0 ± 0·5 MeV was assigned to 64 Co.