Showing papers by "University of Missouri published in 1981"
TL;DR: A review of the use of the technique of solute fluorescence quenching to study the structure and dynamics of proteins and a number of factors are discussed that must be considered in analyzing such data.
1,644 citations
TL;DR: The research results reviewed here suggest that zinc plays an important role in the maintenance of membrane structure and function and physiological pathology is manifested rapidly after dietary zinc deprivation.
619 citations
TL;DR: The dauer larva of Caenorhabditis elegans is a developmentally arrested stage induced by starvation or overcrowding and Mutant phenotypes suggest that the pathway corresponds to neural processing of environmental stimuli.
Abstract: The dauer larva of Caenorhabditis elegans is a developmentally arrested stage induced by starvation or overcrowding. Mutant genes controlling the ability to form dauer larvae interact in a way which allows them to be ordered in a pathway. Mutant phenotypes suggest that the pathway corresponds to neural processing of environmental stimuli.
509 citations
TL;DR: The extension of the Knuth-Bendtx algorithm has produced complete sets of reductions for free commutattve groups, commutative rings wtth umt, and distributive lattices.
Abstract: An extenston of the Knuth-Bendix algorithm for finding complete sets of reductions is described. The extension is intended to handle equational theories which can be split into two parts, R and T, such that each equation m R can be construed as a reduction and T represents an equational theory for which a finite, complete umficat~on algorithm ~s known. The extension ts demonstrated in the case when T is the theory of a fimte number of associaUve and commutatwe functions and to which the extension is presently restricted An tmplementatlon of the extended Knuth-Bendtx algorithm has produced complete sets of reductions for free commutattve groups, commutative rings wtth umt, and distributive lattices.
451 citations
TL;DR: In this article, the estimation of fixed and random effects when the variances and covariances are known is presented in Bayesian terms, point estimates of the unknown variances are computed using the EM algorithm for maximum likelihood estimation from incomplete data.
Abstract: Estimation techniques for linear covariance components models are developed and illustrated with special emphasis on explaining computational processes. The estimation of fixed and random effects when the variances and covariances are known is presented in Bayesian terms, Point estimates of the unknown variances and covariances are computed using the EM algorithm for maximum likelihood estimation from incomplete data. The techniques are illustrated with data on law schools, field mice, and professional football teams.
435 citations
TL;DR: In this article, the capability of waste tire rubber for removing inorganic mercury from solution was evaluated and it was shown that the diffusion of mercury through pores in the rubber sorbent was the rate limiting step regarding mercury uptake.
198 citations
TL;DR: Learning disabilities is a generic term that refers to a heterogeneous group of disorders manifested by significant difficulties in the acquisition and use of listening, speaking, reading, writing, reasoning or mathematical abilities.
Abstract: Learning disabilities is a generic term that refers to a heterogeneous group of disorders manifested by significant difficulties in the acquisition and use of listening, speaking, reading, writing, reasoning or mathematical abilities. These disorders are intrinsic to the individual and presumed to be due to central nervous system dysfunction. Even though a learning disability may occur concomitantly with other handicapping conditions (e.g., sensory impairment, mental retardation, social and emotional disturbance) or environmental influences (e.g., cultural differences, insufficient/inappropriate instruction, psychogenic factors), it is not the direct result of those conditions or influences.
189 citations
TL;DR: Using temperature‐sensitive mutants, it is determined that the same defects which block entry into the dauer stage also prevent recovery of dauer larvae.
Abstract: As a sensory response to starvation or overcrowding, Caenorhabditis elegans second-stage larvae may molt into a developmentally arrested state called the dauer larva When environmental conditions become favorable for growth, dauer larvae mold and resume development Some mutants unable to form dauer larvae are simultaneously affected in a number of sensory functions, including chemotaxis and mating The behavior and sensory neuroanatomy of three such mutants, representing three distinct genetic loci, have been determined and compared with wild-type strain Morphological abnormalities in afferent nerve endings were detected in each mutant Both amphid and outer labial sensilla are affected in the mutant CB1377 (daf-6)X, while another mutant, CB1387 (daf-10)IV, is abnormal in amphidial cells and in the tips of the cephalic neurons The most pleitropic mutant, CB1379 (che-3)I, exhibits gross abnormalities in the tips of virtually all anterior and posterior sensory neurons The primary structural defect in CB1377 appears to be in the nonneuronal amphidial sheath cells The disruption of neural organization in CB1377 is much greater in the adult than in the L2 stage Of all the anterior sense organs examined, only the amphids are morphologically affected in all three mutants Thus, one or more of the amphidial neurons may mediate the sensory signals for entry into the dauer larva stage in normal animals Using temperature-sensitive mutants we determined that the same defects which block entry into the dauer stage also prevent recovery of dauer larvae
189 citations
TL;DR: The relationship between root growth and predawn leaf water potential suggested that root growth was a contributing factor to the drought resistance of white oak.
Abstract: Root growth of white oak (Quercus alba L.) was observed under field conditions using a rhizotron. The effects of temperature, soil water potential, and leaf water potential were evaluated on three measures of root growth and development: root elongation rate, number of growing roots, and root growth intensity (sum of projected root area compared to the total root viewing area). Root elongation rate was linearly related to changes in soil temperature and soil water potential. At soil temperatures less than 17deg;C, temperature was the dominant factor affecting rate of growth, bat at temperatures greater than 17°C soil water potential became the important factor. Unlike root elongation rate, the number of growing roots and root growth intensity increased at cold soil temperatures (8°C) and at soil water potentials of-0.3 to -0.8 MPa. At high soil water potentials (-0.1 MPa) root elongation rate reached a maximum while the number of growing roots and root growth intensity were low. These differences showed that root growth and development were not exclusively affected by the soil environment. In addition, the relationship between root growth and predawn leaf water potential suggested that root growth was a contributing factor to the drought resistance of white oak.
189 citations
TL;DR: The records of 100 consecutive cases of subarachnoid hemorrhage due to ruptured aneurysm were reviewed to determine the incidence and the prognostic implications of seizures during the acute phase.
Abstract: The records of 100 consecutive cases of subarachnoid hemorrhage due to ruptured aneurysm were reviewed to determine the incidence and the prognostic implications of seizures during the acute phase. Seizures occurred in 26% of the patients. Sixty-three per cent of the seizures occurred near the onset
148 citations
TL;DR: Seven grass species on an abundance continuum from common to sparse on a Missouri tallgrass prairie were examined for two diaspore traits (morphology and weight), for three dispersal traits (terminal velocity, and mean and maximum lateral movement propagules released in still air from a height of 1 m), and for two parental traits (culm biomass at maturity and culm height at dispersal.
Abstract: Seven grass species on an abundance continuum from common to sparse on a Missouri tallgrass prairie were examined for two diaspore traits (morphology and weight), for three dispersal traits (terminal velocity, and mean and maximum lateral movement propagules released in still air from a height of 1 m), and for two parental traits (culm biomass at maturity and culm height at dispersal). Dispersal ability, measured in the laboratory as the lateral movement of propagules in the upper 5% (right tail) of the distribution of distances, is inversely correlated (r, =-0.94) with biomass abundance. Under constant conditions, seeds of sparse species travel farther than seeds of common species. Dispersal ability is more closely related to a populational attribute (abundance) than to a more proximate characteristic (diaspore weight). Diaspore weight is closely related (r, = 0.97) to culm biomass of the parent, in apparently simple allometry, and more weakly related (r, = 0.71) to biomass abundance. Large parents make large seeds. The sparsest species, which is small in stature, has light (0.08 to 0.19 mg), flattened diaspores with low terminal velocities (82 to 87 cm sec-1) and achieves lateral movement (up to 460 mm) by tumbling and gliding. Species of intermediate abundance have intermediate stature and diaspore weight (1.0 to 1.8 mg), unornamented propagules, high terminal velocities (191 to 209 cm sec-1) and intermediate dispersal ability (up to 388 mm). The three most common species have heavy propagules (2.2 to 2.8 mg), ornamented with long hairs. Although the ornamentation slows fall (96 to 194 cm sec-1), it acts as a "guide parachute," orienting the propagule so that it falls nearly straight downward. The common species, which morphologically appear adapted to longer dispersal, achieve little lateral movement (up to 235 mm) under laboratory conditions. Terminal velocity is a misleading descriptor of dispersal because diaspores with similar terminal velocities have differing movement patterns. When diaspores of two species (one tall common species and one short sparse species) are released in still air from their natural height, differences in maximum fall distance observed under constant height of release are lost. When dispersal is observed in the field by means of sticky seed traps, the slopes of the dispersal curves (regression coefficient of ln-transformed number of seeds caught on distance from the clump) do not differ from common and sparse species, despite the fact that seeds of the common species are released from greater heights. The orderly differences in dispersal behavior among species due to subtleties of morphology observed under laboratory conditions are masked in
TL;DR: Spontaneous kicking of a single leg in normal, month-old infants who are crying in anticipation of a feeding shows a morphological and temporal structure similar to that of asingle limb in mature locomotion in a number of species, supporting the probability that human locomotion is controlled by a central program.
TL;DR: I analysed the triggering contexts of over 14,000 bouts of rhythmical stereotypies of the legs, arms, and whole torso observed in 20 normal infants during their first year to find non-alert states and interactions with the caregiver were disproportionately associated with leg and torso stereotypies.
TL;DR: This purified sphingomyelinase D was identified as a poisonous toxin that can developed typical dermonecrotic spider lesions when injected into experimental animals at levels expected to be delivered in a normal bite.
TL;DR: White pollen in corn (in contrast to normal yellow) is determined by the double recessive condition for the anthocyanin factor c2 with a newly discovered factor, whp.
Abstract: White pollen in corn (in contrast to normal yellow) is determined by the double recessive condition for the anthocyanin factor c2 with a newly discovered factor, whp. The pigmentation is determined by the genotype of the sporophyte bearing the pollen rather than by the genotype of the pollen grain itself. Pollinations made with white pollen have been unsuccessful. Deposition of flavonoids in the pollen grain appears to be essential to normal pollen function.
TL;DR: Although the fermentation produced increased availability of nutrients, it did not produce change in the proximate analyses and protein and carbohydrate appeared to be more available after the fermentation than before the fermentation.
Abstract: A natural lactic fermentation of ground grain sorghum produced significant increases (P < 0.001) in available lysine/leucine, isoleucine, and methionine. The protein quality, expressed as relative nutritive value, increased significantly (P < 0.001) as a result of fermentation. Niacin and thiamin increased significantly (P < 0.001) and riboflavin also increased (P < 0.05) during the fermentation. Protein and carbohydrate appeared to be more available after the fermentation than before the fermentation. Although the fermentation produced increased availability of nutrients, it did not produce change in the proximate analyses.
TL;DR: Temperature-sensitive mutants representing six different genes have been subjected to temperature-shift and -pulse experiments in order to define the times of temperature sensitivity (TSPs), and the exceptional mutant, daf-14, has its TSP within the first larval stage.
TL;DR: The data suggest an H+/NO3− cotransport mechanism for nitrate uptake and Lemna gibba cells with a low Em showed no depolarisation or even slight hyperpolarisation upon nitrate addition.
TL;DR: Under the framework of a stochastic point process of failures, this paper discusses basic ways to characterize reliability and results pertaining to the appealing alternative of superimposed processes are reviewed.
Abstract: Under the framework of a stochastic point process of failures, this paper discusses basic ways to characterize reliability. The distinction between the failure rate of a process, useful for repairable systems, and the failure rate of a distribution, useful for nonrepairable systems, is drawn. The paper then concentrates on modeling the wearout characteristics of repairable system reliability. Neither the homogeneous Poisson nor the renewal processes will suffice for this purpose. The nonhomogeneous Poisson process is appealing as a general wearout model, but it too has nonintuitive features; for example, the distribution of first failure determines the entire process. This leads us to search for other alternatives and to consider the reliability characteristics of general point processes of failures. Results pertaining to the appealing alternative of superimposed processes are reviewed.
TL;DR: In this paper, the authors present a mediation paradigm which serves as the basis for an analysis of the process and a review of the various mediation techniques, and suggest suggested procedures for future mediation research.
Abstract: Mediation is a complex social process which facilitates interpersonal, intergroup, and international negotiations. However, at present, neither the nature nor the potential of mediation is adequately understood because insufficient effort has been devoted to the analysis and study of the process. In order to enhance our understanding and the potential utility of the procedure, this article presents a mediation paradigm which serves as the basis for an analysis of the process and a review of the various techniques. Subsequently, the paradigm and review underpin suggested procedures for future mediation research.
TL;DR: It is found that a net calcium influx into fusion-competent myoblasts is a requisite step in membrane fusion, in addition to the previously demonstrated requirement for extracellular calcium.
01 Mar 1981-Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology
TL;DR: For instance, the authors found that females preferred the standard call at low to moderate but not high sound pressure levels (SPL) or higher than the synthetic call at 48 to 85 dB.
Abstract: 1.
Four hundred and ninety-nine females ofHyla cinerea made 820 responses in two-choice playback experiments conducted at sound pressure levels (SPL's) between 48 and 85 dB. About one-third of the animals responded at 48 dB, and the percentage increased as a function of SPL.
2.
Females did not show a preference for a standard synthetic call with two components (0.9 + 3.0 kHz) of equal relative amplitude over a single-component (0.9 kHz) call at 48 dB SPL, but chose the bimodal stimulus at 54 dB and higher SPL's (Table 1).
3.
Females chose the standard call over calls in which the high-frequency peak was attenuated by 12 or 6 dB only when the playback level (overall SPL) of the two sounds was 72 dB or higher (Figs. 1 and 2).
4.
Females chose the standard call over one in which the low-frequency peak was attenuated by 12 dB over the entire range of playback levels (48 to 85 dB); when the low-frequency peak was attenuated by 6 dB, females preferred the standard call at low to moderate but not high SPL's (Figs. 3 and 4).
5.
The behavioral results are related to acoustic communication in the natural environment and to basic neurophysiological data from the auditory system ofH. cinerea.
TL;DR: This article found that the enhanced persuasion found in the multiple-source/multiple-argument condition is the result of additional message elaboration elicited by the combination of different sources an argument, but when the message was accompanied by a distractor, this persuasive advantage disappeared.
Abstract: Holding constant information about the number of sources and number of arguments to which they might be exposed, subjects viewed one source presenting three different arguments, three sources presenting different versions of a single argument, or three sources presenting three different arguments (one each) in favor of a counterattitudinal position. For hayf of the subjects, this message was accompanied by a distraction task. In the single task conditions, replicating Harkins and Petty (1981), three-source/three-arguments subjects were more persuaded than subjects in the other two conditions, but when the message was accompanied by a distractor, this persuasive advantage disappeared. Since distraction also led to disruption of favorable thought production, but left recall unaffected, these data are consistent with the view that the enhanced persuasion found in the multiple-source/multiple-argument condition is the result of additional message elaboration elicited by the combination of different sources an...
TL;DR: Electrophoretic assessment of maize mutants lacking cytochrome f and b6 activity supports the suggestion that the four polypeptides characterized here correspond to the subunits of photosynthetic cytochromes.
TL;DR: This article reviewed 13 studies dealing with empirical relationships between perceived task scope and employee performance and found that most studies use less than adequate measures of employee performance, and although a causal relationship is assumed, reciprocal or reverse causality may exist.
Abstract: We review 13 studies dealing with empirical relationships between perceived task scope and employee performance. Results from these studies are contradictory and inconclusive. Most studies use less than adequate measures of employee performance. Moreover, although a causal relationship is assumed, reciprocal or reverse causality may exist. There is a clear need for further theoretical explication and improved laboratory and field research aimed at enhancing both construct validity and substantive considerations.
TL;DR: High phage production coupled with very low infectivity make fKN16 suitable as a vector for DNA cloning experiments requiring a high level of biological containment and may also be useful in studying the role of the gene III protein in the filamentous phage life cycle.
TL;DR: The enhanced intestinal sugar transport produced by high blood sugar is inhibited by phloretin but not by phlorizin and is completely eliminated in cycloheximide-treated animals.
Abstract: The increased sugar transport was examined in the isolated small intestine of streptozotocin-diabetic rats. In the small intestine of these animals, the rate of glucose absorption in vivo is slightly increased, but not that of galactose of 3-O-MG (3-O-Methylglucose); however, in the isolated small intestine, the mucosal-toserosal but not the serosal-to-mucosal flux of glucose, galactose, and 3-O-MG is increased. The enhanced sugar transport is due neither to the direct toxic effect of streptozotocin nor to a lack of circulating insulin. It is not the result of an increased intraepithelial sugar metabolism. Hyperglycemia, produced by i.v. glucose infusion, generates the same increase of the intestinal sugar transport as experimental diabetes but the high blood sugar has to be maintained for 4 h before the intestinal effect appears. Hyperglycemia and hypergalactosemia enhance the intestinal transport of glucose, galactose, and 3-O-MG, but not that of fructose; the transport of the latter is increased by hyperfructosemia. The enhanced intestinal sugar transport produced by high blood sugar is inhibited by phloretin but not by phlorizin and is completely eliminated in cycloheximide-treated animals. It is proposed that sustained high blood sugar induces the synthesis of new carrier sites which are most likely located in the basolateral membrane.
TL;DR: In this paper, El Khadem et al. investigated the reaction of d-glucose with benzoylhydrazine to give the bishydrazone of 3-deoxy-d-erythro -hexos-2-ulose.
TL;DR: The clinical and chromosomal findings in 8 patients with deletions of the long arm of chromosome 4.3 confirm that deletion of 4q31 leads to qter causes a recognizable syndrome, and further define the phenotype of that syndrome.
Abstract: We report the clinical and chromosomal findings in 8 patients with deletions of the long arm of chromosome 4. Four of these patients appear to have terminal deletions beginning in band 4q31, and therefore, lack the digital 1/3 of the long arm of chromosome 4. We confirm that deletion of 4q31 leads to qter causes a recognizable syndrome, and we further define the phenotype of that syndrome. A 5th patient has a horter terminal deletion, ie, 4q33 leads to qter. This deletion causes a milder phenotypic expression than that seen in the severe 4q terminal-deletion syndrome. The remaining 3 patients have interstitial deletions of the long arm of the 4th chromosome, including segments 4q21.1 leads to q25, 4q21.3 leads to q26, and 4q27 leads to q31.3. The phenotypic expression noted in these patients is variable in differs from the 4q terminal-deletion syndrome.
TL;DR: This article investigated the effects of sex (male-male vs. female-female) and sex typing (sex typed-sex typed, sex typed-androgynous, and androgynous-androgynyous) on dyadic posture mirroring between strangers in a waiting room context.
Abstract: This study investigated the effects of sex (male-male vs. female-female) and sex typing (sex typed-sex typed, sex typed-androgynous, and androgynous-androgynous) on dyadic posture mirroring between strangers in a “waiting room” context. Results revealed a significant interaction between sex composition and sex-typing composition such that among sex-typed pairs, females displayed more posture mirroring than males but among androgynous pairs, the effect was reversed with male dyads showing more posture sharing than female dyads. Results also showed a surprising negative relation between mirroring and rapport as well as a negative correlation between mirroring and verbalization. The suggestion made is that individual action in the form of talk and communal engagement in the form of mirroring may represent different modes of being involved in an interaction.