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At least 19 recordsLinked to original sources
PubMed1976

Competitive behavior and perceived aggression.

In groups of 39 males and 39 female undergraduates played a reaction-time game in which descriptions of a player's shock settings were constant or consistently below or above another player's; wins were varied. Ratings of aggression, offensiveness, positivity on semantic scales showed naive subjects considered the offensive or defensive nature of obseved behavior in making ratings.

Aggression↗
PubMed1992

Environmental concern and cooperative-competitive behavior in a simulated commons dilemma.

Commons-dilemma simulation games are designed to examine behavior associated with preservation and destruction of slowly regenerating natural resources. In Experiment 1, 120 introductory psychology students in the United States were assigned to high- or low-environmental-concern conditions based on a median split of their scores from a pretest. They then played either a points game, in which they selected numerical points from a slowly regenerating pool, or a tree game, in which they harvested trees from a jointly managed forest. After the game, subjects were asked to sign a petition for an environmental cause, to participate in a litter pick-up, and to participate in a recycling drive. Neither environmental concern nor proenvironmental behaviors were related to commons dilemma performance. In Experiment 2, 57 other introductory psychology students were assessed on environmental concern and Machiavellian personality, size of other players' harvesting choices, and other players' altruistic choices, all correlated with subjects' outcomes in the game. Overall, cooperation and competition were more important than environmental concern in predicting behavior in the commons dilemma simulation game.

Adult↗
PubMed1978

Behavioral competition: a mechanism for schedule interactions.

Rats pressing a lever for food reinforcement showed large positive-contrast effects when provided with the opportunity for a competing wheel-running response. Positive and negative behavioral contrast may reflect reallocation of competing interim and terminal responses between schedule components following changes in the reinforcement conditions in one component.

Animals↗
PubMed1992

On-line visualization of the competitive behavior of antagonistic bacteria.

To study the interaction between cocultured Listeria monocytogenes and an antagonistic Leuconostoc strain producing an anti-Listeria bacteriocin, flow cytometry, a technique allowing on-line and real-time analysis, was used along with classical microbiological methods. Culture methods and flow cytometric measurements of the mixed culture over time point to a bactericidal action of the lactic acid-producing bacterial strain against L. monocytogenes cells.

Bacteriocins↗
PubMed1992

A crisis related analysis of perceived spectators' behavior in competition.

Spectator behavior in competition is analyzed in terms of spectators' response (positive or negative), or lack of response in reaction to a player's action, or which is independent of a player's action, in a home or away game. This study investigated the perceived contribution of these variables to extreme psychological arousal states (crisis, noncrisis). Forty-eight elite ball-game players responded to a questionnaire asking them to estimate the occurrence probability of the Bayesian combinations among these variables under crisis and noncrisis conditions. An RM-ANOVA procedure revealed that under the crisis condition a negative response, an unsuccessful action, and a home game were rated as more probable, whereas under the noncrisis condition the reverse would be true. The athlete's psychological state was more strongly related to spectator response than to game location or athlete's action. Results are discussed theoretically in reference to the crisis construct.

Arousal↗
PubMed1992

Musical reinforcement of practice behaviors among competitive swimmers.

This study determined whether music could be used as a reinforcer for increasing productive and decreasing nonproductive behavior of 6 competitive swimmers during the dry-land portion of practice session. The swimmers were randomly assigned to either the contingent reinforcement group, who received music for productive behavior, or the noncontingent group, who received music regardless of their training productivity. An ABAB design showed that a large and immediate increase in productive practice behavior and decrease in nonproductive practice behavior occurred during the contingent phase compared to the baseline phase. Subjects rated the musical reinforcement favorably and elected to have the procedure continued.

Child↗
PubMed1979

The prediction of swimming performance in competition from behavioral information.

The swimming performances of the Canadian Team at the 1976 Olympic Games were categorized as being improved or worse than previous best times in the events contested. The two groups had been previously assessed on the Psychological Inventories for Competitive Swimmers. A stepwise multiple-discriminant analysis of the inventory responses revealed that 13 test questions produced a perfect discrimination of group membership. The resultant discriminant functions for predicting performance classification were applied to the test responses of 157 swimmers at the 1977 Canadian Winter National Swimming Championships. Using the same performance classification criteria the accuracy of prediction was not better than chance in three of four sex by performance classifications. This yielded a failure to locate a set of behavioral factors which determine swimming performance improvements in elite competitive circumstances. The possibility of sets of factors which do not discriminate between performances in similar environments or between similar groups of swimmers was raised.

Behavior↗
PubMed1976

Conformations of lysine-sensitive aspartokinase.

1. The technique of differential thermal and proteolytic inactivation has been employed as a conformational probe for the lysine-sensitive aspartokinase (EC 2.7.2.4) of Escherichia coli B. 2. L-Amino acid inhibitors of this enzyme each induce a characteristic enzyme conformation. This is evidenced by rates of thermal and proteolytic inactivation and Arrhenius activation energies for thermal inactivation which are characteristic of the amino acid present. 3. Phenylalanine and leucine binding are mutually exclusive as evidenced by competitive behavior in thermal inactivation experiments, suggesting a hydrophobic amino acid binding site with broad specificity. 4. The phenylalanine-dependent conformation and the leucine-dependent conformation differ considerably. In comparison with the native enzyme, the former is more labile to proteolysis by trypsin whereas the latter is more stable. First-order rate constants for thermal inactivation of the phenylalanine- and leucine-dependent conformations are, respectively, about one-half and one-tenth that of the native enzyme. 5. Items 3 and 4 taken together suggest that the conformations are ligand induced and do not arise via ligand stabilization of spontaneously arising conformers.

Aspartate Kinase↗
PubMed1992

Protein-DNA interactions at the H4-site III upstream transcriptional element of a cell cycle regulated histone H4 gene: differences in normal versus tumor cells.

Upstream sequences of the H4 histone gene FO108 located between nt -418 to -213 are stimulatory for in vivo transcription. This domain contains one protein/DNA interaction site (H4-Site III) that binds factor H4UA-1. Based on methylation interference, copper-phenanthroline protection, and competition assays, we show that H4UA-1 interacts with sequences between nt -345 to -332 containing an element displaying sequence-similarity with the thyroid hormone response element (TRE). Using gel retardation assays, we also demonstrate that H4UA-1 binding activity is abolished at low concentrations of Zn2+ (0.75 mM), a characteristic shared with the thyroid hormone (TH) receptor DNA binding protein. Interestingly, phosphatase-treatment of nuclear proteins inhibits formation of the H4UA-1 protein/DNA complex, although a complex with higher mobility (H4UA-1b) can be detected; both complexes share identical protein-DNA contacts and competition behaviors. These findings suggest that phosphorylation may be involved in the regulation of H4-Site III protein/DNA interactions by directly altering protein/protein associations. H4-Site III interactions were examined in several cell culture systems during cell growth and differentiation. We find that H4UA-1 binding activity is present during the cell cycle of both normal diploid and transformed cells. However, during differentiation of normal diploid rat calvarial osteoblasts, we observe a selective loss of the H4UA-1/H4-Site III interaction, concomitant with an increase of the H4UA-1b/H4-Site III complex, indicating modifications in the heteromeric nature of protein/DNA interactions during downregulation of transcription at the cessation of proliferation. Transformed cells have elevated levels of H4UA-1, whereas H4UA-1b is predominantly present in normal diploid cells; this alteration in the ratio of H4UA-1 and H4UA-1b binding activities may reflect deregulation of H4-Site III interactions in transformed cells. We propose that H4-Site III interactions may contribute, together with protein/DNA interactions at proximal regulatory sequences, in determining the level of H4-FO108 histone gene transcription.

Base Sequence↗
PubMed1976

A behavioral classification of welfare children from survey data.

From survey data on 1000 urban Welfare AFDC children aged six to eighteen, a hierarchical cluster analysis yielded six distinct behavioral types of Welfare children. Characteristics of each type, and its relationship to treatment, ethnicity, and other variables are discussed. Advantages of this system of behavioral classification for research and population assessment are outlined.

Achievement↗
PubMed1992

[An analysis of the joint activities of primates in a situation of delayed spatial choice].

A leader-dominant baboon of a couple took practically all the food in the situation of spatial delayed choice. The subdominant baboon managed to get some food, too, using fast changes of behavioral tactics during the experimental session. The obvious negative state of the subdominant baboon resulted in a severe neurotic breakdown. Long delays in the experimental scheme enabled the subdominant to get up to 50% of the food reinforcement due to the dominant baboons mistakes. The role of changes in the tactics of the monkeys is discussed.

Animals↗
PubMed1992

Modulation of the mitochondrial megachannel by divalent cations and protons.

In patch-clamp experiments on rat liver mitoplasts, the 1.3 nanosiemens (in 150 mM KCl) mitochondrial megachannel was activated by Ca2+ and competitively inhibited by Mg2+, Mn2+, Ba2+, and Sr2+. Cyclosporin A, which inhibits the megachannel, also showed a competitive behavior versus Ca2+. The pore is regulated by pH in the physiological range; lower pH values cause its closure in a Ca(2+)-reversible manner. The modulating sites involved in these effects are located on the matrix side of the membrane. As illustrated in the companion paper (Bernardi, P., Vassanelli, S., Veronese, P., Colonna, R., Szabó, I., and Zoratti, M. (1992) J. Biol. Chem. 267, 2934-2939), the calcium-induced permeability transition of mitochondria is affected by these various agents in a similar manner. The results support the identification of the megachannel with the pore believed to be involved in the permeabilization process. The kinetic characteristics of the single channel events support the idea that the megachannel is composed of cooperating subunits.

Animals↗
PubMed1976

Reduced nicotinamide adenine dinucleotide phosphate, a structural and conformational probe of chicken liver fatty acid synthetase.

Structural and conformational organization of chicken liver fatty acid synthetase has been probed using its fluorescent coenzyme, NADPH. Three NADPH binding sites per mole of the enzyme complex, of apparently identical dissociation constant (KD = 0.6 muM) can be titrated at temperatures above 12 degrees. These results are in disagreement with the earlier studies of Hsu and Wagner (Hsu, R. Y., and Wagner, B. J. (1970) Biochemistry, 9, 245-251) in which four such sites could be titrated. At 12 degrees, the composite sites split into two subsets: a pair of sites with a KD of 0.3 muM and a third site with a Kd of 1.1 muM. At lower temperatures (5 degrees or 2 degrees), the site with weak affinity disappears, leaving a pair of sites with a Kd of 0.5 muM. Similar observations were made when the enzyme was modified with phenylmethylsulfonyl fluoride, a specific and selective inhibitor of fatty acyl-CoA deacylase (s) of the pigeon liver enzyme complex (Kumar, S. (1975) J. Biol. Chem. 250, 5150-5158). Partial modification with phenylmethylsulfonyl fluoride elicits a NADPH binding response similar to the binding observed at 12 degrees, i.e. two sets of binding sites with nonidentical dissociation constants. Further modification corresponding to the complete loss of deacylase function results in a set of two apparently identical binding sites, and the third site is not available for titration. The modified enzyme retains the two reductase functions as measured by the model substrates, acetoacetyl-N-acetylcysteamine and crotonyl-CoA. Furthermore, the addition of acetyl- and malonyl-CoA (100 muM each) to the modified enzyme lowers the NADPH binding affinity by a factor of 3. Other observations show that the quantum yield, as measured by the ratio of fluorescence intensity of bound and free NADPH, changes with temperature and ionic strength. Lowering the temperature from 30 degrees to 2 degrees increases the enhancement ratio by 50%, whereas increase in ionic strength from 0.05 to 0.2 M potassium phosphate lowers it to 50% of the original level. Measurement of NADPH binding in the presence of NADP+, NADH, NAD+ and adenosine-2'-monophospho-5'-diphosphoribose demonstrates that NADP+ shows competitive behavior for NADPH sites (KD = 10.6 muM), whereas NADH and NAD+ show noncompetitive (KD (apparent) = nearly 600 muM) and rather complicated interactions implicating nonspecific conformational alteration of the enzyme complex. The behavior of adenosine 2'-monophospho-5'-diphosphoribose is intermediate between NADP+ and NADH. These data are discussed in terms of substrate-mediated conformational changes and the moles of each of the reductase enzymes per mole of the enzyme complex, the polarity of the NADPH binding region, and the probable structure of the nicotinamide moiety when bound to the enzyme.

Animals↗