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	Author	Hagen, S.J.; Eaton, W.A.
	Title	Two-state expansion and collapse of a polypeptide			Type	Journal Article
	Year	2000	Publication	Journal of Molecular Biology	Abbreviated Journal	J Mol Biol
	Volume	301	Issue	4	Pages	1019-1027
	Keywords	Animals; Computer Simulation; Cytochrome c Group/chemistry/metabolism; Horses; Kinetics; Lasers; Models, Chemical; Peptides/chemistry/metabolism; Protein Conformation; Protein Denaturation; *Protein Folding; Spectrometry, Fluorescence; Temperature; Thermodynamics
	Abstract	The initial phase of folding for many proteins is presumed to be the collapse of the polypeptide chain from expanded to compact, but still denatured, conformations. Theory and simulations suggest that this collapse may be a two-state transition, characterized by barrier-crossing kinetics, while the collapse of homopolymers is continuous and multi-phasic. We have used a laser temperature-jump with fluorescence spectroscopy to measure the complete time-course of the collapse of denatured cytochrome c with nanosecond time resolution. We find the process to be exponential in time and thermally activated, with an apparent activation energy approximately 9 k(B)T (after correction for solvent viscosity). These results indicate that polypeptide collapse is kinetically a two-state transition. Because of the observed free energy barrier, the time scale of polypeptide collapse is dramatically slower than is predicted by Langevin models for homopolymer collapse.
	Address	Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Building 5, Bethesda, MD, 20892-0520, USA
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0022-2836	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:10966803			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3790
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	Author	Paz-y-Miño C. G.; Bond, A.B.; Kamil, A.C.; Balda, R.P.
	Title	Pinyon jays use transitive inference to predict social dominance			Type	Journal Article
	Year	2004	Publication	Nature	Abbreviated Journal	Nature
	Volume	430	Issue	7001	Pages	778-781
	Keywords	Animals; Cognition/physiology; Group Structure; Male; Social Dominance; Songbirds/*physiology
	Abstract	Living in large, stable social groups is often considered to favour the evolution of enhanced cognitive abilities, such as recognizing group members, tracking their social status and inferring relationships among them. An individual's place in the social order can be learned through direct interactions with others, but conflicts can be time-consuming and even injurious. Because the number of possible pairwise interactions increases rapidly with group size, members of large social groups will benefit if they can make judgments about relationships on the basis of indirect evidence. Transitive reasoning should therefore be particularly important for social individuals, allowing assessment of relationships from observations of interactions among others. Although a variety of studies have suggested that transitive inference may be used in social settings, the phenomenon has not been demonstrated under controlled conditions in animals. Here we show that highly social pinyon jays (Gymnorhinus cyanocephalus) draw sophisticated inferences about their own dominance status relative to that of strangers that they have observed interacting with known individuals. These results directly demonstrate that animals use transitive inference in social settings and imply that such cognitive capabilities are widespread among social species.
	Address	Center for Avian Cognition, School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588, USA
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1476-4687	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:15306809			Approved	no
	Call Number	refbase @ user @; Equine Behaviour @ team @ room B 3.029			Serial	352
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	Author	Shettleworth, S.J.
	Title	Cognitive science: rank inferred by reason			Type	Journal Article
	Year	2004	Publication	Nature	Abbreviated Journal	Nature
	Volume	430	Issue	7001	Pages	732-733
	Keywords	Animals; Cognition/physiology; Group Structure; Male; Social Dominance; Songbirds/*physiology
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1476-4687	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:15306792			Approved	no
	Call Number	refbase @ user @			Serial	365
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	Author	Conradt, L.; Roper, T.J.
	Title	Group decision-making in animals			Type	Journal Article
	Year	2003	Publication	Nature	Abbreviated Journal	Nature
	Volume	421	Issue	6919	Pages	155-158
	Keywords	Animals; Behavior, Animal/physiology; Decision Making; Democracy; Group Processes; *Models, Biological; Population Density; Social Behavior
	Abstract	Groups of animals often need to make communal decisions, for example about which activities to perform, when to perform them and which direction to travel in; however, little is known about how they do so. Here, we model the fitness consequences of two possible decision-making mechanisms: 'despotism' and 'democracy'. We show that under most conditions, the costs to subordinate group members, and to the group as a whole, are considerably higher for despotic than for democratic decisions. Even when the despot is the most experienced group member, it only pays other members to accept its decision when group size is small and the difference in information is large. Democratic decisions are more beneficial primarily because they tend to produce less extreme decisions, rather than because each individual has an influence on the decision per se. Our model suggests that democracy should be widespread and makes quantitative, testable predictions about group decision-making in non-humans.
	Address	School of Biological Sciences, University of Sussex, Brighton BN1 9QG, UK. l.conradt@sussex.ac.uk
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0028-0836	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:12520299			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	5136
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	Author	Kihara, H.; Nakatani, H.; Hiromi, K.; Hon-Nami, K.
	Title	Kinetic studies on redox reactions of hemoproteins. I. Reduction of thermoresistant cytochrome c-552 and horse heart cytochrome c by ferrocyanide			Type	Journal Article
	Year	1977	Publication	Biochimica et Biophysica Acta	Abbreviated Journal	Biochim Biophys Acta
	Volume	460	Issue	3	Pages	480-489
	Keywords	Animals; Bacteria; Cytochrome c Group; Ferrocyanides; Horses; Kinetics; Mathematics; Oxidation-Reduction; Spectrophotometry; Spectrophotometry, Ultraviolet; Temperature; Thermodynamics
	Abstract	The oxidation-reduction reaction of horse heart cytochrome c and cytochrome c (552, Thermus thermophilus), which is highly thermoresistant, was studied by temperature-jump method. Ferrohexacyanide was used as reductant. (Formula: see text.) Thermodynamic and activation parameters of the reaction obtained for both cytochromes were compared with each other. The results of this showed that (1) the redox potential of cytochrome c-552, + 0.19 V, is markedly less than that of horse heart cytochrome c. (2) deltaHox of cytochrome c-552 is considerably lower than that of horse heart cytochrome c. (3) deltaSox and deltaSred of cytochrome c-552 are more negative than those of horse heart cytochrome c. (4) kred of cytochrome c-552 is much lower than that of horse heart cytochrome c at room temperature.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0006-3002	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:195599			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3815
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	Author	Ridge, J.A.; Baldwin, R.L.; Labhardt, A.M.
	Title	Nature of the fast and slow refolding reactions of iron(III) cytochrome c			Type	Journal Article
	Year	1981	Publication	Biochemistry	Abbreviated Journal	Biochemistry
	Volume	20	Issue	6	Pages	1622-1630
	Keywords	Animals; Ascorbic Acid; *Cytochrome c Group; Guanidines; Horses; Kinetics; Oxidation-Reduction; Protein Conformation; Spectrum Analysis
	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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0006-2960	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:6261802			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3809
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	Author	Jacobs, A.; Maumy, M.; Petit, O.
	Title	*The influence of social organisation on leadership in brown lemurs (Eulemur fulvus fulvus) in a controlled environment*			Type	Journal Article
	Year	2008	Publication	Behavioural Processes	Abbreviated Journal	Behav. Process.
	Volume	79	Issue	2	Pages	111-113
	Keywords	Animals; Decision Making; Dominance-Subordination; Exploratory Behavior; Female; Group Structure; Leadership; Lemur/psychology; Male; Sex Factors; *Social Environment
	Abstract	Studies on leadership during group movements in several lemur species showed that females were responsible for the travelling choices concerning time and direction. Interestingly, in these species females are dominant over males. We investigated the influence of social organisation upon leadership processes by studying a lemur species in which social organisation is characterized by the absence of female dominance: the brown lemur (Eulemur fulvus fulvus). The study was conducted on a semi-free ranging group of 11 individuals and the analysis performed on 69 group movements showed that all the individuals could initiate a group movement. In 34 cases, the whole group moved. There was no significant difference in the number of start attempts or in the number of group members involved from one initiator to another. Moreover, there was no effect of sex or age of the initiator on the number of individuals following it or on the speed of the joining process. Therefore, the leadership observed is widely distributed to all group members. These results support the hypothesis of an influence of social organisation upon the decision-making processes but still remain to be studied in a more relevant ecological context.
	Address	IPHC-DEPE, Equipe d'ethologie des primates, UMR 7178, Centre National de la Recherche Scientifique-Universite Louis Pasteur and Centre de Primatologie, Strasbourg, France
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0376-6357	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:18586413			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	5127
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	Author	Saigo, S.
	Title	A transient spin-state change during alkaline isomerization of ferricytochrome c			Type	Journal Article
	Year	1981	Publication	Journal of Biochemistry	Abbreviated Journal	J Biochem (Tokyo)
	Volume	89	Issue	6	Pages	1977-1980
	Keywords	Animals; *Cytochrome c Group; Horses; Hydrogen-Ion Concentration; Isomerism; Kinetics; Myocardium/enzymology; Oxidation-Reduction; Spectrophotometry
	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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-924X	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:6270075			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3808
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	Author	Dyson, H.J.; Beattie, J.K.
	Title	Spin state and unfolding equilibria of ferricytochrome c in acidic solutions			Type	Journal Article
	Year	1982	Publication	The Journal of Biological Chemistry	Abbreviated Journal	J Biol Chem
	Volume	257	Issue	5	Pages	2267-2273
	Keywords	Animals; *Cytochrome c Group; Electron Spin Resonance Spectroscopy; Heme; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium; Protein Binding; Protein Conformation; Spectrophotometry; Temperature
	Abstract	Equilibrium, stopped flow, and temperature-jump spectrophotometry have been used to identify processes in the unfolding of ferricytochrome c in acidic aqueous solutions. A relaxation occurring in approximately 100 microseconds involves perturbation of a spin-equilibrium between two folded conformers of the protein with methionine-80 coordinated or dissociated from the heme iron. The protein unfolds more slowly, in milliseconds, with dissociation and protonation of histidine-18. These two transitions appear cooperative in equilibrium measurements at low (0.01 M) ionic strength, but are separated at higher (0.10 M) ionic strength. They are resolved under both conditions in the dynamic measurements. The spin-equilibrium description permits a unified explanation of a number of properties of ferricytochrome c in acidic aqueous solutions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-9258	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:6277891			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3807
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	Author	Abbruzzetti, S.; Viappiani, C.; Small, J.R.; Libertini, L.J.; Small, E.W.
	Title	Kinetics of histidine deligation from the heme in GuHCl-unfolded Fe(III) cytochrome C studied by a laser-induced pH-jump technique			Type	Journal Article
	Year	2001	Publication	Journal of the American Chemical Society	Abbreviated Journal	J Am Chem Soc
	Volume	123	Issue	27	Pages	6649-6653
	Keywords	Animals; Bacterial Proteins; Cytochrome c Group/chemistry; Guanidine/chemistry; Heme/chemistry; Histidine/chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Lasers; Ligands; Protein Folding
	Abstract	We have developed an instrumental setup that uses transient absorption to monitor protein folding/unfolding processes following a laser-induced, ultrafast release of protons from o-nitrobenzaldehyde. The resulting increase in [H(+)], which can be more than 100 microM, is complete within a few nanoseconds. The increase in [H(+)] lowers the pH of the solution from neutrality to approximately 4 at the highest laser pulse energy used. Protein structural rearrangements can be followed by transient absorption, with kinetic monitoring over a broad time range (approximately 10 ns to 500 ms). Using this pH-jump/transient absorption technique, we have examined the dissociation kinetics of non-native axial heme ligands (either histidine His26 or His33) in GuHCl-unfolded Fe(III) cytochrome c (cyt c). Deligation of the non-native ligands following the acidic pH-jump occurs as a biexponential process with different pre-exponential factors. The pre-exponential factors markedly depend on the extent of the pH-jump, as expected from differences in the pK(a) values of His26 and His33. The two lifetimes were found to depend on temperature but were not functions of either the magnitude of the pH-jump or the pre-pulse pH of the solution. The activation energies of the deligation processes support the suggestion that GuHCl-unfolded cyt c structures with non-native histidine axial ligands represent kinetic traps in unfolding.
	Address	Dipartimento di Fisica, Universita di Parma, Istituto Nazionale per la Fisica della Materia, 43100 Parma, Italy
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language	English	Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0002-7863	ISBN		Medium
	Area		Expedition		Conference
	Notes	PMID:11439052			Approved	no
	Call Number	Equine Behaviour @ team @			Serial	3788
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