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Hoff, M. P., Nadler, R. D., & Maple, T. L. (1981). Development of infant independence in a captive group of lowland gorillas. Dev Psychobiol, 14(3), 251–265.
Abstract: In March 1976, 3 lowlands gorillas (Gorilla gorilla gorilla) were born to primiparous females living with an adult male in a large compound at the field station of the Yerkes Regional Primate Research Center of Emory University. Observations of parent and infant behavior began at the birth of the infants, using several methods of data collection. This report focuses on the development of independence in these infants over the 1st 1 1/2 years of life. As expected, measures of mother-infant contact and proximity decreased with age. Several measures suggested that infant independence developed as an interactive process between mothers and infants, with primary responsibility changing over the months of study. Maternal behaviors that served to maintain mother-infant contact were found to decrease with age, with an eventual shift to infant responsibility for contact maintenance. Additionally, the adult male appeared to influence developing independence as reflected in the maternal protectiveness evoked by his behavior.
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Boice, R. (1981). Behavioral comparability of wild and domesticated rats. Behav Genet, 11(5), 545–553.
Abstract: The oft-repeated concern for the lack of behavioral comparability of domestic rats with wild forms of Rattus norvegicus is unfounded. Laboratory rats appear to show the potential for all wild-type behaviors, including the most dramatic social postures. Moreover, domestics are capable of assuming a feral existence without difficulty, one where they readily behave in a fashion indistinguishable from wild rats. The one behavioral difference that is clearly established concerns performance in laboratory learning paradigms. The superiority of domestics in these laboratory tasks speaks more to quieting the concerns of degeneracy theorists than to problems of using domestic Norway rats as subjects representative of their species.
Keywords: Animals; *Behavior, Animal; Female; Genetics, Behavioral; Intelligence; Learning; Male; Rats/*genetics
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Clutton-Brock, J. (1981). Domesticated animals from early times. Austin: Univ of Texas Press. |
Kihara, H. (1981). Comparison of the redox reactions of various types of cytochrome c with iron hexacyanides. Biochimica et Biophysica Acta (BBA) – Bioenergetics, 634, 93–104.
Abstract: The dynamic behavior of various types of cytochromes c in the redox reaction with iron hexacyanides was studied using a temperature-jump method in order to elucidate the molecular mechanism of the redox reaction of cytochromes with their oxidoreductants. Transmittance after the temperature jump changed through a single exponential decay for all cytochromes investigated. Under a constant concentration of anion, the redox reaction of various types of cytochrome c with iron hexacyanides was analyzed according to the scheme: Ki=kt/k-i (i=1,2,3) where C(III) and C(II) are ferric and ferrous cytochromes, respectively, Fe(III) and Fe(II) are ferri- and ferrocyanides, respectively, C(III) [middle dot] Fe(II) is the ferricytochrome-ferrocyanide complex and C(II) [middle dot] Fe(III) is the ferrocytochrome-ferricyanide complex. When step B is slower than the other two steps A and C, τ-1 can be represented approximately as where the bar over the variables denotes the equilibrium value. In a large excess of ferrocyanide against cytochrome, we can estimate k2, k-2, K1 and K3 independently. In the case of horse cytochrome c at 18[degree sign]C in 0.1 M phosphate buffer at pH 7 with 0.3 M KNO3, the estimated parameters are k2 = 100 +/- 50 s-1, k-2 = (3.5 +/- 1.0) [middle dot] 103 s-1, K1 = 15 +/- 7 M-1 and K3 = (8.5 +/- 1.5) [middle dot] 10-4 M. From the same experiments for seven cytochromes (cytochrome c from horse, tuna, Candida krusei, Saccharomyces oviformis, Rhodospirillum rubrum cytochrome c2, Spirulina platensis cytochrome c-554 and Thermus thermophilus cytochrome c-552), the following results can be deduced. (1) Each parameter defined in the scheme above (k2, k-2, K1, K3) diverged beyond the error range. Above all, k2 values of cytochromes c-554 and c-552 are as large as 1 [middle dot] 104 s-1 and much larger than those for the other cytochromes (to 50 approx. 700 S-1). (2) The variance of k2K1 and k-2/K3 are relatively less than the variances of individual parameters (k2, k-2, K1 and K3), which suggests that the values of k2K1 and k-2/K3 have been conserved during the course of evolution.
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Bruns, E. (1981). Estimation of the breeding value of stallions from the tournament performance of their offspring. Livestock Production Science, 8(5), 465–473.
Abstract: Data from horse-riding competitions recorded in Germany in 1976 and 1977 have been analysed to estimate genetic parameters for performance traits of riding horses measured in dressage, jumping competitions and trials. The performance traits analysed were logarithmic earnings per start, relative place number, and place value. The results are the following. 1. (1) Heritability and repeatability estimates for performance in dressage shows are 0.2 and 0.4 respectively. Corresponding estimates for performance in jumping competitions are 20% less. No genetic differences are found between stallions for performance in trials.2. (2) A selection index for estimating the breeding value of stallions was constructed by using the repeated performances of their offspring in dressage and jumping shows. For this purpose, performance data for at least ten progeny should be available. The correlation between the breeding values estimated from the dressage and jumping performances of the same stallions was approximately zero.3. (3) Reliable progeny-testing requires that the assumptions of mating stallions at random, selecting progeny randomly, and distributing them equally across environmental effects be fulfilled.4. (4) The genetic use of breeding values of stallions estimated from the performance of their progeny is opposed by the prolongation of the generation interval. This can be partly overcome by sampling young stallions and making use of the test results for young progeny only.
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Saigo, S. (1981). Kinetic and equilibrium studies of alkaline isomerization of vertebrate cytochromes c. Biochim Biophys Acta, 669(1), 13–20.
Abstract: Equilibria and kinetics of alkaline isomerization of seven ferricytochromes c from vertebrates were studied by pH-titration and pH-jump methods in the pH region of 7-12. In the equilibrium behavior, no significant difference was detected among the cytochromes c, whereas marked differences in the kinetic behavior were observed. According to the kinetic behavior of the isomerization, the cytochromes c examined fall into three classes: Group I (horse, sheep, dog and pigeon cytochromes c), Group II (tuna and bonito cytochromes c) and Group III (rhesus monkey cytochrome c). The kinetic results are interpreted in terms of the sequential scheme: Neutral form in equilibrium with fast Transient form in equilibrium with slow Alkaline form where the neutral and alkaline forms are the species stable at neutral and alkaline pH, respectively, and the transient form is a kinetic intermediate. From comparison of the primary sequences of the seven cytochromes c and the classification of these cytochromes c, it is concluded that the amino acid substitution Phe/Tyr at the 46-th position has a major influence on the kinetic behavior. In Group II and III cytochromes c, the ionization of Tyr-46 is suggested to bring about loosening of the heme crevice and thus facilitate the ligand replacement involved in the isomerization.
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Andersson, P., Kvassman, J., Lindstrom, A., Olden, B., & Pettersson, G. (1981). Effect of NADH on the pKa of zinc-bound water in liver alcohol dehydrogenase. Eur J Biochem, 113(3), 425–433.
Abstract: Equilibrium constants for coenzyme binding to liver alcohol dehydrogenase have been determined over the pH range 10--12 by pH-jump stop-flow techniques. The binding of NADH or NAD+ requires the protonated form of an ionizing group (distinct from zinc-bound water) with a pKa of 10.4. Complex formation with NADH exhibits an additional dependence on the protonation state of an ionizing group with a pKa of 11.2. The binding of trans-N,N-dimethylaminocinnamaldehyde to the enzyme . NADH complex is prevented by ionization of the latter group. It is concluded from these results that the pKa-11.2-dependence of NADH binding most likely derives from ionization of the water molecule bound at the catalytic zinc ion of the enzyme subunit. The pKa value of 11.2 thus assigned to zinc-bound water in the enzyme . NADH complex appears to be typical for an aquo ligand in the inner-sphere ligand field provided by the zinc-binding amino acid residues in liver alcohol dehydrogenase. This means that the pKa of metal-bound water in zinc-containing enzymes can be assumed to correlate primarily with the number of negatively charged protein ligands coordinated by the active-site zinc ion.
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Ridge, J. A., Baldwin, R. L., & Labhardt, A. M. (1981). Nature of the fast and slow refolding reactions of iron(III) cytochrome c. Biochemistry, 20(6), 1622–1630.
Abstract: The fast and slow refolding reactions of iron(III) cytochrome c (Fe(III) cyt c), previously studied by Ikai et al. (Ikai, A., Fish, W. W., & Tanford, C. (1973) J. Mol. Biol. 73, 165--184), have been reinvestigated. The fast reaction has the major amplitude (78%) and is 100-fold faster than the slow reaction in these conditions (pH 7.2, 25 degrees C, 1.75 M guanidine hydrochloride). We show here that native cyt c is the product formed in the fast reaction as well as in the slow reaction. Two probes have been used to test for formation of native cyt c. absorbance in the 695-nm band and rate of reduction of by L-ascorbate. Different unfolded species (UF, US) give rise to the fast and slow refolding reactions, as shown both by refolding assays at different times after unfolding (“double-jump” experiments) and by the formation of native cyt c in each of the fast and slow refolding reactions. Thus the fast refolding reaction is UF leads to N and the slow refolding reaction is Us leads to N, where N is native cyt c, and there is a US in equilibrium UF equilibrium in unfolded cyt c. The results are consistent with the UF in equilibrium US reaction being proline isomerization, but this has not yet been tested in detail. Folding intermediates have been detected in both reactions. In the UF leads to N reaction, the Soret absorbance change precedes the recovery of the native 695-nm band spectrum, showing that Soret absorbance monitors the formation of a folding intermediate. In the US leads to N reaction an ascorbate-reducible intermediate has been found at an early stage in folding and the Soret absorbance change occurs together with the change at 695 nm as N is formed in the final stage of folding.
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Saigo, S. (1981). A transient spin-state change during alkaline isomerization of ferricytochrome c. J Biochem (Tokyo), 89(6), 1977–1980.
Abstract: Kinetic difference spectra during the alkaline isomerization of ferricytochrome c were obtained by the pH-jump method in the range of 540 to 655 nm. The spectrum of the transient intermediate, which appears during the course of the isomerization, was reproduced from the spectra. The intermediate showed an intense absorption band at 600 nm, indicating that it is a high spin or mixed spin species. This is in contrast to the stable neutral and alkaline forms which are low spin species. The transient spin-state change during the isomerization was also observed upon rapid oxidation of ferrocytochrome c at alkaline pH.
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Heird, J. C., Lennon, A. M., & Bell, R. W. (1981). Effects of early experience on the learning ability of yearling horses. J. Anim Sci., 53(5), 1204–1209.
Abstract: Twenty-four yearling Quarter Horse fillies were divided into three groups (I) very limited handling, (II) intermediate handling and (III) extensive handling. At about 14 months of age, each horse was preconditioned for 2 weeks and then run in a simple place-learning T-maze test in which it had to locate its feed. Thirty trials were run daily for 20 days, with the location of the feed changed each day. To retire from the maze, a horse had to meet the criterion: 11 correct responses in 12 tries, with the last eight being consecutive. Horses in Group II required the fewest trials to reach criterion. These horses also learned more and had the highest percentage of correct responses (P less than .05). Mean trainability tended to predict learning ability; however, trainability and trials to criterion were not significantly correlated. Mean emotionality scores indicated a tendency for horses in the intermediately handled group to be less emotional than those in Group I or III. Results indicated that horses with an intermediate amount of handling scored higher on an intermediate test of learning. All handled horses scored higher on learning tests than those not handled.
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