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Author Andersen, N.H.; Norgaard, A.; Jensen, T.J.; Ulstrup, J. url  openurl
  Title (down) Sequential unfolding of the two-domain protein Pseudomonas stutzeri cytochrome c4 Type Journal Article
  Year 2002 Publication Journal of Inorganic Biochemistry Abbreviated Journal  
  Volume 88 Issue 3-4 Pages 316-327  
  Keywords P. stutzeri cytochrome c4; Sequential unfolding; Di-haem protein; Unfolding  
  Abstract P. stutzeri cytochrome c4 is a di-haem protein, composed of two globular domains each with His-Met coordinated haem, and a hydrogen bond network between the domains. The domain foldings are highly symmetric but with specific differences including structural differences of ligand coordination, and different spin states of the oxidised haem groups. We have studied unfolding of oxidised P. stutzeri cyt c4 induced thermally and by chemical denaturants. Horse heart cyt c was a reference molecule. Isothermal unfolding induced by guanidinium chloride and acid was followed by Soret, α/β, and 701-nm band absorption, and by far-UV circular dichroism spectroscopy. Multifarious patterns emerge, but the two domains clearly unfold sequentially. One phase, assigned to unfolding of the N-terminal domain, proceeds at guanidinium concentrations up to [approximate]1.0 M. This is followed by two overlapping phases at higher concentrations. The intermediate state maintains Fe-Met coordination, assigned to the C-terminal domain. Interdomain interaction is reflected in decreasing values of the cooperativity parameters. Differential scanning calorimetry shows a single peak, but two peaks appear when guanidinium chloride up to 0.4 M is present. This reflects different chemical action in chemical and thermal unfolding. Acid-induced unfolding kinetics was addressed by pH jumps using diode array stopped-flow techniques. Three kinetic phases in the 701 nm Fe-Met marker band, and four phases in the Soret and α/β bands, spanning 4-1000 ms could be distinguished on pH jumps from 7.5 to the range 2.5-3.5. In this range of time and pH cyt c appears to unfold in no more than two phases. Spectral properties of the kinetic intermediates could be identified. Sequential domain unfolding, formation of high-spin states, and an intermediate state with Fe-Met coordination to a single haem group are features of the unfolding kinetics.  
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  Call Number refbase @ user @ Serial 3973  
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Author Parrish, J.K.; Viscido, S.V.; Grunbaum, D. url  openurl
  Title (down) Self-Organized Fish Schools: An Examination of Emergent Properties Type Journal Article
  Year 2002 Publication Biol Bull Abbreviated Journal Biol Bull  
  Volume 202 Issue 3 Pages 296-305  
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  Abstract Heterogeneous, “aggregated” patterns in the spatial distributions of individuals are almost universal across living organisms, from bacteria to higher vertebrates. Whereas specific features of aggregations are often visually striking to human eyes, a heuristic analysis based on human vision is usually not sufficient to answer fundamental questions about how and why organisms aggregate. What are the individual-level behavioral traits that give rise to these features? When qualitatively similar spatial patterns arise from purely physical mechanisms, are these patterns in organisms biologically significant, or are they simply epiphenomena that are likely characteristics of any set of interacting autonomous individuals? If specific features of spatial aggregations do confer advantages or disadvantages in the fitness of group members, how has evolution operated to shape individual behavior in balancing costs and benefits at the individual and group levels? Mathematical models of social behaviors such as schooling in fishes provide a promising avenue to address some of these questions. However, the literature on schooling models has lacked a common framework to objectively and quantitatively characterize relationships between individual-level behaviors and group-level patterns. In this paper, we briefly survey similarities and differences in behavioral algorithms and aggregation statistics among existing schooling models. We present preliminary results of our efforts to develop a modeling framework that synthesizes much of this previous work, and to identify relationships between behavioral parameters and group-level statistics. N1 -  
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  Call Number Equine Behaviour @ team @ Serial 5254  
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Author Hemelrijk, C.K. url  openurl
  Title (down) Self-Organization and Natural Selection in the Evolution of Complex Despotic Societies Type Journal Article
  Year 2002 Publication Biol Bull Abbreviated Journal Biol Bull  
  Volume 202 Issue 3 Pages 283-288  
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  Abstract Differences between related species are usually explained as separate adaptations produced by individual selection. I discuss in this paper how related species, which differ in many respects, may evolve by a combination of individual selection, self-organization, and group-selection, requiring an evolutionary adaptation of only a single trait. In line with the supposed evolution of despotic species of macaques, we take as a starting point an ancestral species that is egalitarian and mildly aggressive. We suppose it to live in an environment with abundant food and we put the case that, if food becomes scarce and more clumped, natural selection at the level of the individual will favor individuals with a more intense aggression (implying, for instance, biting and fierce fighting). Using an individual-centered model, called DomWorld, I show what happens when the intensity of aggression increases. In DomWorld, group life is represented by artificial individuals that live in a homogeneous world. Individuals are extremely simple: all they do is flock together and, upon meeting one another, they may perform dominance interactions in which the effects of winning and losing are self-reinforcing. When the intensity of aggression in the model is increased, a complex feedback between the hierarchy and spatial structure results; via self-organization, this feedback causes the egalitarian society to change into a despotic one. The many differences between the two types of artificial society closely correspond to those between despotic and egalitarian macaques in the real world. Given that, in the model, the organization changes as a side effect of the change of one single trait proper to an egalitarian society, in the real world a despotic society may also have arisen as a side effect of the mutation of a single trait of an egalitarian species. If groups with different intensities of aggression evolve in this way, they will also have different gradients of hierarchy. When food is scarce, groups with the steepest hierarchy may have the best chance to survive, because at least a small number of individuals in such a group may succeed in producing offspring, whereas in egalitarian societies every individual is at risk of being insufficiently fed to reproduce. Therefore, intrademic group selection (selection within an interbreeding group) may have contributed to the evolution of despotic societies. N1 -  
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  Call Number Equine Behaviour @ team @ Serial 5201  
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Author Clement, T.S.; Zentall, T.R. openurl 
  Title (down) Second-order contrast based on the expectation of effort and reinforcement Type Journal Article
  Year 2002 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process  
  Volume 28 Issue 1 Pages 64-74  
  Keywords Animals; Columbidae; Discrimination Learning; Random Allocation; *Reinforcement (Psychology)  
  Abstract Pigeons prefer signals for reinforcement that require greater effort (or time) to obtain over those that require less effort to obtain (T. S. Clement, J. Feltus, D. H. Kaiser, & T. R. Zentall, 2000). Preference was attributed to contrast (or to the relatively greater improvement in conditions) produced by the appearance of the signal when it was preceded by greater effort. In Experiment 1, the authors of the present study demonstrated that the expectation of greater effort was sufficient to produce such a preference (a second-order contrast effect). In Experiments 2 and 3, low versus high probability of reinforcement was substituted for high versus low effort, respectively, with similar results. In Experiment 3, the authors found that the stimulus preference could be attributed to positive contrast (when the discriminative stimuli represented an improvement in the probability of reinforcement) and perhaps also negative contrast (when the discriminative stimuli represented reduction in the probability of reinforcement).  
  Address Department of Psychology, University of Kentucky, Lexington, Kentucky 40506-0044, USA  
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  Series Volume Series Issue Edition  
  ISSN 0097-7403 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11868235 Approved no  
  Call Number refbase @ user @ Serial 241  
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Author Huebener, E. url  isbn
openurl 
  Title (down) Schmeichelnder Sitz, atmender Schenkel, flüsternder Zügel Type Book Whole
  Year 2002 Publication Olms Presse, Hildesheim Abbreviated Journal  
  Volume Issue 2. erweiterte Auflage Pages 220  
  Keywords  
  Abstract HÜBENER, EBERHARD, Schmeichelnder Sitz, atmender Schenkel,

flüsternder Zügel

Vom feinfühligen, partnerschaftlichen Umgang mit dem Pferd und über Nöte

der bundesdeutschen Reiterei. Mit einem Geleitwort von Dr. Reiner Klimke

2. ergänzte Aufl. Hildesheim 2002. 223 S. mit 63 Abb., davon 3 farbig. Gebunden. Reihe:

(NOVA HIPPOLOGICA.) ISBN: 3-487-08408-2

Dieses Buch beantwortet eine Reihe zentraler Fragen zur Reitlehre und zum

Umgang mit dem Pferd gründlich und leicht verständlich. Es ist daher hilfreich

für alle, die sich am und auf dem Pferd gern helfen lassen. Ob sie nun nur zum

Vergnügen oder mit turniersportlichen Ambitionen reiten. Ob sie lernen oder

lehren.

Der vorliegenden zweiten Auflage ist eine neue Arbeit des Autors beigebunden:

Nachdem eine Video-Analyse seinen “selbsttätigen Schenkel” bestätigt hat, wird

jetzt endlich auch das “Sitz-Rätsel” definitiv gelöst.

Die Video-Technik hat ermöglicht, das Zusammenspiel von Gangart, Bewegungen

von Pferderumpf und -rücken, Sitz des Reiters und Hilfengebung zum Nutzen

des Reiter-Rückgrats, der keineswegs beliebig belastbaren Wirbelsäule des

Pferdes und kultivierten, feinfühligen Reitens zu entschlüsseln.

Reitunterricht kann anders aussehen. Irrwege sind vermeidbar geworden.
 
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  Language Deutsch Summary Language Original Title  
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  ISSN 0948-9708 ISBN 3-487-08408-2 Medium  
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  Notes Approved no  
  Call Number Reiten Lesen Denken @ eberhardhuebener @ Serial 874  
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Author Kirkpatrick, J.F.; Turner, A. openurl 
  Title (down) Reversibility of action and safety during pregnancy of immunization against porcine zona pellucida in wild mares (Equus caballus) Type Journal Article
  Year 2002 Publication Reproduction (Cambridge, England) Supplement Abbreviated Journal Reprod Suppl  
  Volume 60 Issue Pages 197-202  
  Keywords Animals; *Animals, Wild; Antigens/administration & dosage; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; Fertility; *Horses; Immunization, Secondary/veterinary; Membrane Glycoproteins/administration & dosage; Population Control; Pregnancy; *Receptors, Cell Surface; Safety; Swine; Time Factors; Vaccines, Contraceptive/*administration & dosage  
  Abstract Contraceptive management of publicly valued wildlife species requires safeguards to ensure that these populations are preserved in a healthy state. In addition, reversibility of contraceptive effects and safety in pregnant animals are major concerns. A population of wild horses has been immunized against porcine zona pellucida (PZP) over a 12 year period on Assateague Island National Seashore, MD (ASIS). Mares initially received one or two 65 microg inoculations and once a year 65 microg booster inoculations, all delivered by dart. All young mares aged > 2 years were treated with PZP for 3 consecutive years regardless of whether they have bred successfully and they were then removed from treatment until they had foaled. All mares vaccinated for 1 or 2 consecutive years became fertile again and 69% of mares treated for 3 consecutive years returned to fertility. All five mares treated for 4 or 5 consecutive years have also returned to fertility, but over longer periods of time. Mares treated for 7 consecutive years have not returned to fertility, but several, while still infertile, have started ovulating again. There was no difference in survival rates between foals born to treated and untreated mares, and PZP treatment of pregnant mares did not affect subsequent fertility of their female offspring.  
  Address Science and Conservation Center, ZooMontana, Billings 59106, USA. zoolab@wtp.net  
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  ISSN 1477-0415 ISBN Medium  
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  Notes PMID:12220160 Approved no  
  Call Number refbase @ user @ Serial 141  
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Author Dingemanse, N.J.; Both, C.; Drent, P.J.; van Oers, K.; van Noordwijk, A.J. url  doi
openurl 
  Title (down) Repeatability and heritability of exploratory behaviour in great tits from the wild Type Journal Article
  Year 2002 Publication Animal Behaviour Abbreviated Journal Anim. Behav.  
  Volume 64 Issue 6 Pages 929-938  
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  Abstract We investigated whether individual great tits, Parus major, vary consistently in their exploratory behaviour in a novel environment and measured the repeatability and heritability of this trait. Wild birds were caught in their natural habitat, tested in the laboratory in an open field test on the following morning, then released at the capture site. We measured individual consistency of exploratory behaviour for recaptured individuals (repeatability) and estimated the heritability with parent-offspring regressions and sibling analyses. Measures of exploratory behaviour of individuals at repeated captures were consistent in both sexes and study areas (repeatabilities ranged from 0.27 to 0.48). Exploration scores did not differ between the sexes, and were unrelated to age, condition at fledging or condition during measurement. Heritability estimates were 0.22-0.41 (parent-offspring regressions) and 0.37-0.40 (sibling analyses). We conclude that (1) consistent individual variation in open field behaviour exists in individuals from the wild, and (2) this behavioural variation is heritable. This is one of the first studies showing heritable variation in a behavioural trait in animals from the wild, and poses the question of how this variation is maintained under natural conditions. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.  
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  ISSN 0003-3472 ISBN Medium  
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  Call Number Equine Behaviour @ team @ Serial 5389  
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Author Boyd, L.; Bandi, N. url  doi
openurl 
  Title (down) Reintroduction of takhi, Equus ferus przewalskii, to Hustai National Park, Mongolia: time budget and synchrony of activity pre- and post-release Type Journal Article
  Year 2002 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.  
  Volume 78 Issue 2-4 Pages 87-102  
  Keywords Equids; Przewalski's horses; Takhi; Behaviour patterns; Time budgets; Behavioural synchrony; Reintroduction  
  Abstract A harem of takhi (Equus ferus przewalskii) was observed during introduction to the Hustain Nuruu Steppe Reserve of Mongolia. The goals were to examine whether the harem exhibited significant behavioural synchrony, whether release had an effect on time budget, and what the implications might be regarding acclimatisation to the wild. Behaviours were scan sampled every 10 min between the hours of 06:00 and 22:00, twice before release, twice immediately after release, and twice 2 years after reintroduction. Time budgets were constructed from these data. Considerable behavioural synchrony was evidenced both before and after release. Crepuscular grazing and midday resting were typical, regardless of the date relative to release. Upon release, the amount of time spent moving doubled for all age classes. It is suggested that this increase resulted from exploration. The amount of time spent grazing and standing remained unchanged; the increased amount of time spent moving came at the expense of resting. Two years later, the horses still spent more time moving than when captive. Somewhat less time was spent grazing, although the difference was not significant. More time was spent resting in 1996 than immediately after release. These time budgets provide evidence of successful acclimatisation to the wild. Trekking between favoured sites could account for the persistent increase in time spent moving, with concomitantly less time needed to meet nutritional needs by grazing and more time available for resting. Housing captive takhi in large enclosures is evidently insufficient to permit the amount of movement exhibited by this wild harem. The time budget of the 1- and 2-year olds was more similar to that of adults than foals, indicating approaching adulthood. That 1- and 2-year olds were nursed, without loss of body condition by the dam, provided additional evidence that the takhi achieved excellent nutritional status in the wild.  
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  Call Number Equine Behaviour @ team @ Serial 3690  
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Author Dudchenko, P.A.; Davidson, M. doi  openurl
  Title (down) Rats use a sense of direction to alternate on T-mazes located in adjacent rooms Type Journal Article
  Year 2002 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 5 Issue 2 Pages 115-118  
  Keywords Animals; *Cognition; Male; *Maze Learning; Rats; Rats, Inbred Strains; Space Perception  
  Abstract Lister hooded rats were trained on a forced-sample T-maze alternation task in an environment lacking spatial landmarks. An early study of spontaneous alternation on the T-maze had shown that rats use a “spatial sense” to select alternate maze arms across mazes. As this phenomenon may provide a useful tool for studying the neural substrates of a directional sense, we wished to confirm this finding on a different version of the T-maze task, with well-trained animals. We found that rats successfully selected the appropriate maze arm when the choice phase of the task was presented on a second maze, oriented in the same direction, and located in an adjacent room. However, choice performance fell to chance level when the second maze was oriented 90 degrees relative to the first. This result suggests that the rats do not simply alternate turns across the two environments, but rather that they rely on a sense of direction that is carried across environments.  
  Address Department of Psychology, University of Stirling, Stirling FK9 4LA, UK. p.a.dudchenko@stir.ac.uk  
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  ISSN 1435-9448 ISBN Medium  
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  Notes PMID:12150036 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2608  
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Author Campbell, F.M.; Heyes, C.M. url  doi
openurl 
  Title (down) Rats smell: odour-mediated local enhancement, in a vertical movement two-action test Type Journal Article
  Year 2002 Publication Animal Behaviour. Abbreviated Journal Anim. Behav.  
  Volume 63 Issue 6 Pages 1055-1063  
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  Abstract In two experiments, hungry rats, Rattus norvegicus, were present in one side of an operant chamber while a conspecific demonstrator in the adjacent compartment moved a single lever either up or down for a food reward. During a subsequent test session, in which these rats were allowed access to the lever for the first time, all responses were rewarded regardless of their direction. In experiment 1, rats that were prevented from observing the direction of lever movement by means of a screen showed a reliable demonstrator-consistent response bias, while rats that had observed the direction of lever movement and in addition had access to any odour cues deposited on the lever did not. In experiment 2, each rat observed another rat (the `viewed' demonstrator) moving a lever either up or down. They were then transferred into the test compartment of a different operant chamber in which another rat (the `box' demonstrator) had moved the lever in the same direction as the viewed demonstrator or in the opposite direction. These observer rats showed a reliable preference for their box demonstrator's direction, but responded in the opposite direction to their viewed demonstrator. Taken together, the results of these experiments suggest that directional responding by rats in a vertical movement two-action test is influenced by demonstrator-deposited odour cues in addition to visual experience of a demonstrator's behaviour. Furthermore, while odour-mediated local enhancement gave rise to demonstrator-consistent responding, visual observation of a conspecific appeared to have the reverse effect. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.  
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  Call Number Serial 2089  
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