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Author Gonzalez-Fernandez, J.M.; Atta, S.E.
Title Facilitated transport of oxygen in the presence of membranes in the diffusion path Type Journal Article
Year 1982 Publication Biophysical Journal Abbreviated Journal (up) Biophys J
Volume 38 Issue 2 Pages 133-141
Keywords Animals; Biological Transport, Active; Cell Membrane/*metabolism; Diffusion; Dogs; Horses; Humans; Kinetics; Mathematics; *Models, Biological; Muscles/*metabolism; Oxygen/*metabolism
Abstract Most of the experimental observations on facilitated transport have been done with millipore filters, and all the theoretical studies have assumed homogeneous spatial properties. In striated muscle there exist membranes that may impede the diffusion of the carrier myoglobin. In this paper a theoretical study is undertaken to analyze the transport in the presence of membranes in the diffusion path. For the numerical computations physiologically relevant values of the parameters were chosen. The numerical results indicate that the presence of membranes tends to decrease the facilitation. For the nonlinear chemical kinetics of the reaction of oxygen with the carrier, this decrement also depends on the location of the membranes. At the higher oxygen concentration side of each membrane the flow of combined oxygen is transferred to the flow of dissolved oxygen. The reverse process occurs at the lower concentration side. Jump discontinuities of the concentration of the oxygen-carrier compound at each membrane are associated with these transfers. The decrement of facilitation is due to the cumulative effect of these jump discontinuities.
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 0006-3495 ISBN Medium
Area Expedition Conference
Notes PMID:7093418 Approved no
Call Number Equine Behaviour @ team @ Serial 3806
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Author Rands, S.A.; Cowlishaw, G.; Pettifor, R.A.; Rowcliffe, J.M.; Johnstone, R.A.
Title The emergence of leaders and followers in foraging pairs when the qualities of individuals differ Type Journal Article
Year 2008 Publication BMC Evolutionary Biology Abbreviated Journal (up) BMC Evol Biol
Volume 8 Issue Pages 51
Keywords Animals; *Feeding Behavior; *Food Chain; *Models, Biological; *Social Dominance
Abstract BACKGROUND: Foraging in groups offers animals a number of advantages, such as increasing their likelihood of finding food or detecting and avoiding predators. In order for a group to remain together, there has to be some degree of coordination of behaviour and movement between its members (which may in some cases be initiated by a decision-making leader, and in other cases may emerge as an underlying property of the group). For example, behavioural synchronisation is a phenomenon where animals within a group initiate and then continue to conduct identical behaviours, and has been characterised for a wide range of species. We examine how a pair of animals should behave using a state-dependent approach, and ask what conditions are likely to lead to behavioural synchronisation occurring, and whether one of the individuals is more likely to act as a leader. RESULTS: The model we describe considers how the energetic gain, metabolic requirements and predation risks faced by the individuals affect measures of their energetic state and behaviour (such as the degree of behavioural synchronisation seen within the pair, and the value to an individual of knowing the energetic state of its colleague). We explore how predictable changes in these measures are in response to changes in physiological requirements and predation risk. We also consider how these measures should change when the members of the pair are not identical in their metabolic requirements or their susceptibility to predation. We find that many of the changes seen in these measures are complex, especially when asymmetries exist between the members of the pair. CONCLUSION: Analyses are presented that demonstrate that, although these general patterns are robust, care needs to be taken when considering the effects of individual differences, as the relationship between individual differences and the resulting qualitative changes in behaviour may be complex. We discuss how these results are related to experimental observations, and how the model and its predictions could be extended.
Address Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. sean.rands@bristol.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 1471-2148 ISBN Medium
Area Expedition Conference
Notes PMID:18282297 Approved no
Call Number Equine Behaviour @ team @ Serial 5126
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Author Biro, D.; Sumpter, D.J.T.; Meade, J.; Guilford, T.
Title From Compromise to Leadership in Pigeon Homing Type Journal Article
Year 2006 Publication Current Biology Abbreviated Journal (up) Curr Biol
Volume 16 Issue 21 Pages 2123-2128
Keywords Animal Migration; Animals; Columbidae/*physiology; Decision Making; *Flight, Animal; *Homing Behavior; Models, Biological; Orientation; *Social Behavior; *Social Dominance
Abstract Summary A central problem faced by animals traveling in groups is how navigational decisions by group members are integrated, especially when members cannot assess which individuals are best informed or have conflicting information or interests , , , and . Pigeons are now known to recapitulate faithfully their individually distinct habitual routes home , and , and this provides a novel paradigm for investigating collective decisions during flight under varying levels of interindividual conflict. Using high-precision GPS tracking of pairs of pigeons, we found that if conflict between two birds' directional preferences was small, individuals averaged their routes, whereas if conflict rose over a critical threshold, either the pair split or one of the birds became the leader. Modeling such paired decision-making showed that both outcomes--compromise and leadership--could emerge from the same set of simple behavioral rules. Pairs also navigated more efficiently than did the individuals of which they were composed, even though leadership was not necessarily assumed by the more efficient bird. In the context of mass migration of birds and other animals, our results imply that simple self-organizing rules can produce behaviors that improve accuracy in decision-making and thus benefit individuals traveling in groups , and .
Address Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom. daro.biro@zoo.ox.ac.uk
Corporate Author Thesis
Publisher Place of Publication Editor
Language Englisch Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-9822 ISBN Medium
Area Expedition Conference
Notes PMID:17084696 Approved no
Call Number Serial 2026
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Author Harcourt, J.L.; Ang, T.Z.; Sweetman, G.; Johnstone, R.A.; Manica, A.
Title Social feedback and the emergence of leaders and followers Type Journal Article
Year 2009 Publication Current Biology : CB Abbreviated Journal (up) Curr Biol
Volume 19 Issue 3 Pages 248-252
Keywords Analysis of Variance; Animals; Appetitive Behavior/physiology; *Feedback; Great Britain; *Leadership; Markov Chains; Models, Biological; Monte Carlo Method; Smegmamorpha/*physiology; *Social Behavior; Video Recording
Abstract In many animal groups, certain individuals consistently appear at the forefront of coordinated movements [1-4]. How such leaders emerge is poorly understood [5, 6]. Here, we show that in pairs of sticklebacks, Gasterosteus aculeatus, leadership arises from individual differences in the way that fish respond to their partner's movements. Having first established that individuals differed in their propensity to leave cover in order to look for food, we randomly paired fish of varying boldness, and we used a Markov Chain model to infer the individual rules underlying their joint behavior. Both fish in a pair responded to each other's movements-each was more likely to leave cover if the other was already out and to return if the other had already returned. However, we found that bolder individuals displayed greater initiative and were less responsive to their partners, whereas shyer individuals displayed less initiative but followed their partners more faithfully; they also, as followers, elicited greater leadership tendencies in their bold partners. We conclude that leadership in this case is reinforced by positive social feedback.
Address Department of Zoology, University of Cambridge, Cambridge, 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 0960-9822 ISBN Medium
Area Expedition Conference
Notes PMID:19185497 Approved no
Call Number Equine Behaviour @ team @ Serial 5123
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Author Munoz-Sanz, A.
Title [Christopher Columbus flu. A hypothesis for an ecological catastrophe] Type Journal Article
Year 2006 Publication Enfermedades Infecciosas y Microbiologia Clinica Abbreviated Journal (up) Enferm Infecc Microbiol Clin
Volume 24 Issue 5 Pages 326-334
Keywords Animals; Atlantic Islands; Birds; Chickens; Disease Outbreaks/*history; Disease Reservoirs; Disease Susceptibility; Ecology; Europe/ethnology; History, 15th Century; Horses; Humans; Indians, South American; Influenza A virus/classification/genetics/pathogenicity; Influenza in Birds/epidemiology/history/transmission/virology; Influenza, Human/epidemiology/*history/mortality/transmission; Models, Biological; Orthomyxoviridae Infections/epidemiology/history/veterinary/virology; Poultry Diseases/epidemiology/history/transmission/virology; Reassortant Viruses/genetics/pathogenicity; Species Specificity; Sus scrofa; Swine Diseases/history/transmission/virology; Terminology; West Indies/epidemiology
Abstract When Christopher Columbus and his men embarked on the second Colombian expedition to the New World (1493), the crew suffered from fever, respiratory symptoms and malaise. It is generally accepted that the disease was influenza. Pigs, horses and hens acquired in Gomera (Canary Islands) traveled in the same ship. The pigs may well have been the origin of the flu and the intermediary hosts for genetic recombination of other viral subtypes. The Caribbean archipelago had a large population of birds, the natural reservoir of the avian influenza virus. In this ecological scenario there was a concurrence of several biological elements that had never before coexisted in the New World: pigs, horses, the influenza virus and humans. We propose that birds are likely to have played an important role in the epidemiology of the flu occurring on the second Colombian trip, which caused a fatal demographic catastrophe, with an estimated mortality of 90% among the natives.
Address Unidad de Patologia Infecciosa, Hospital Universitario Infanta Cristina, Servicio Extremeno de Salud, Universidad de Extremadura, Badajoz, Espana. infectio@unex.es
Corporate Author Thesis
Publisher Place of Publication Editor
Language Spanish Summary Language Original Title La gripe de Cristobal Colon. Hipotesis sobre una catastrofe ecologica
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0213-005X ISBN Medium
Area Expedition Conference
Notes PMID:16762260 Approved no
Call Number Equine Behaviour @ team @ Serial 2624
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Author Rollot, Y.; Lecuyer, E.; Chateau, H.; Crevier-Denoix, N.
Title Development of a 3D model of the equine distal forelimb and of a GRF shoe for noninvasive determination of in vivo tendon and ligament loads and strains Type Journal Article
Year 2004 Publication Equine Veterinary Journal Abbreviated Journal (up) Equine Vet J
Volume 36 Issue 8 Pages 677-682
Keywords Animals; Biomechanics; Floors and Floorcoverings; Forelimb/*physiology/ultrasonography; Gait/physiology; Horses/*physiology; Image Processing, Computer-Assisted; Imaging, Three-Dimensional/methods/*veterinary; Ligaments, Articular/*physiology; Locomotion/*physiology; Models, Biological; Shoes; Tendons/*physiology; Toe Joint/physiology/ultrasonography
Abstract REASONS FOR PERFORMING STUDY: As critical locomotion events (e.g. high-speed and impacts during racing, jump landing) may contribute to tendinopathies, in vivo recording of gaits kinematic and dynamic parameters is essential for 3D reconstruction and analysis. OBJECTIVE: To propose a 3D model of the forelimb and a ground reaction force recording shoe (GRF-S) for noninvasively quantifying tendon and ligament loads and strains. METHODS: Bony segments trajectories of forelimbs placed under a power press were recorded using triads of ultrasonic kinematic markers linked to the bones. Compression cycles (from 500-6000 N) were applied for different hoof orientations. Locations of tendon and ligament insertions were recorded with regard to the triads. The GRF-S recorded GRF over the hoof wall and used four 3-axis force sensors sandwiched between a support shoe and the shoe to be tested. RESULTS: Validation of the model by comparing calculated and measured superficial digital flexor tendon strains, and evaluation of the role of proximal interphalangeal joint in straight sesamoidean ligament and oblique sesamoidean ligament strains, were successfully achieved. Objective comparisons of the 3 components of GRF over the hoof for soft and hard grounds could be recorded, where the s.d. of GRF norm was more important on hard ground at walk and trot. CONCLUSIONS: Soft grounds (sand and rubber) dissipate energy by lowering GRF amplitude and diminish bounces and vibrations at impact. At comparable speed, stance phase was longer on soft sand ground. POTENTIAL RELEVANCE: The conjugate use of the GRF-S and the numerical model would help to quantify and analyse ground/shoe combination on comfort, propulsion efficiency or lameness recovery.
Address UMR INRA-ENVA de Biomecanique et Pathologie Locomotrice du Cheval, Ecole Nationale Veterinaire d'Alfort, 7, Avenue du General de Gaulle, 94704 Maisons-Alfort, 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 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:15656495 Approved no
Call Number Equine Behaviour @ team @ Serial 3769
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Author Galloux, P.; Barrey, E.
Title Components of the total kinetic moment in jumping horses Type Journal Article
Year 1997 Publication Equine Veterinary Journal. Supplement Abbreviated Journal (up) Equine Vet J Suppl
Volume Issue 23 Pages 41-44
Keywords Algorithms; Animals; Exertion/*physiology; Female; Gravitation; Horses/*physiology; Kinetics; Locomotion/*physiology; Male; Models, Biological; Movement/*physiology; Video Recording
Abstract Thirty horses were filmed with a panning camera operating at 50 frames/s as they jumped over a 1.20 x 1.20 m fence. The markers of 9 joints on the horse and 7 joints on the rider were tracked in 2D with the TrackEye system. The centre of gravity and moment of inertia of each segment were calculated using a geometric algorithm and a cylindric model, respectively. The kinetic moment of each part of the horse was calculated after filtering, and resampling of data. This method showed the relative contribution of each body segment to the body overall rotation during the take-off, jump and landing phases. It was found that the trunk, hindlimbs and head-neck had the greatest influence. The coordination between the motion of the body segments allowed the horse to control its angular speed of rotation over the fence. This remained nearly constant during the airborne phase (120 +/- 5 degrees/s). During the airborne phase, the kinetic moment was constant because its value was equal to the moment of the external forces (722 +/- 125 kg x m2/s).
Address Ecole Nationale d'Equitation, Terrefort, Saumur, 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 ISBN Medium
Area Expedition Conference
Notes PMID:9354287 Approved no
Call Number Equine Behaviour @ team @ Serial 3797
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Author Reimers, M.; Schwarzenberger, F.; Preuschoft, S.
Title Rehabilitation of research chimpanzees: stress and coping after long-term isolation Type Journal Article
Year 2007 Publication Hormones and Behavior Abbreviated Journal (up) Horm Behav
Volume 51 Issue 3 Pages 428-435
Keywords Adaptation, Psychological/*physiology; Animals; *Animals, Laboratory; Exploratory Behavior; Hydrocortisone/analysis/metabolism; Male; Models, Biological; *Pan troglodytes; Social Dominance; Social Environment; *Social Isolation/psychology; Stress/*rehabilitation/veterinary; Time
Abstract We report on the permanent retirement of chimpanzees from biomedical research and on resocialization after long-term social isolation. Our aim was to investigate to what extent behavioral and endocrine measures of stress in deprived laboratory chimpanzees can be improved by a more species-typical social life style. Personality in terms of novelty responses, social dominance after resocialization and hormonal stress susceptibility were affected by the onset of maternal separation of infant chimpanzees and duration of deprivation. Chimpanzees, who were separated from their mothers at a younger age and kept in isolation for more years appeared to be more timid personalities, less socially active, less dominant and more susceptible to stress, as compared to chimpanzees with a less severe deprivation history. However, permanent retirement from biomedical research in combination with therapeutic resocialization maximizing chimpanzees' situation control resulted in reduced fecal cortisol metabolite levels. Our results indicate that chimpanzees can recover from severe social deprivation, and may experience resocialization as less stressful than solitary housing.
Address Department of Natural Sciences, Institute of Biochemistry, University of Veterinary Medicine, Veterinarplatz 1, 1210 Vienna, Austria. reimers@wild-vet.at
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 0018-506X ISBN Medium
Area Expedition Conference
Notes PMID:17292368 Approved no
Call Number Equine Behaviour @ team @ Serial 4188
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Author Rosa, P.A.J.; Azevedo, A.M.; Aires-Barros, M.R.
Title Application of central composite design to the optimisation of aqueous two-phase extraction of human antibodies Type Journal Article
Year 2007 Publication Journal of Chromatography. A Abbreviated Journal (up) J Chromatogr A
Volume 1141 Issue 1 Pages 50-60
Keywords Analysis of Variance; Animals; Antibodies/*chemistry/*isolation & purification; Buffers; Chemical Fractionation/*methods; Horses; Humans; Hydrophobicity; Isoelectric Point; Models, Biological; Molecular Weight; Myoglobin/chemistry/isolation & purification; Osmolar Concentration; Phase Transition; Polyethylene Glycols; Serum Albumin/chemistry/isolation & purification; Sodium Chloride
Abstract The partition of human antibodies in aqueous two-phase systems (ATPSs) of polyethylene glycol (PEG) and phosphate was systematically studied using first pure proteins systems and then an artificial mixture of proteins containing 1mg/ml human immunoglobulin G (IgG), 10mg/ml serum albumin and 2mg/ml myoglobin. Preliminary results obtained using pure proteins systems indicated that the PEG molecular weight and concentration, the pH value and the salts concentration had a pronounced effect on the partitioning behaviour of all proteins. For high ionic strengths and pH values higher than the isoelectric point (pI) of the contaminant proteins, IgG could be selectively recovered on the top phase. According to these results, a face centred composite design was performed in order to optimise the purification of IgG from the mixture of proteins. The optimal conditions for the isolation of IgG were observed for high concentrations of NaCl and low concentrations of both phase forming components. The best purification was achieved using an ATPS containing 8% (w/w) PEG 3350, 10% (w/w) phosphate pH 6 and 15% (w/w) NaCl. A recovery yield of 101+/-7%, a purity of 99+/-0% and a yield of native IgG of 97+/-4% were obtained. Back extraction studies of IgG to a new phosphate phase were performed and higher yields were obtained using 10% phosphate buffer at pH 6. The total extraction yield was 76% and the purity 100%.
Address IBB Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Tecnico, Av Rovisco Pais, 1049-001 Lisbon, Portugal
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 0021-9673 ISBN Medium
Area Expedition Conference
Notes PMID:17196214 Approved no
Call Number Serial 1842
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Author Tobin, T.; Combie, J.D.
Title Performance testing in horses: a review of the role of simple behavioral models in the design of performance experiments Type Journal Article
Year 1982 Publication Journal of Veterinary Pharmacology and Therapeutics Abbreviated Journal (up) J Vet Pharmacol Ther
Volume 5 Issue 2 Pages 105-118
Keywords Analgesics, Opioid/pharmacology; Animals; Apomorphine/pharmacology; Behavior, Animal/*drug effects; Dose-Response Relationship, Drug; Fentanyl/pharmacology; Horses/*physiology; Methylphenidate/pharmacology; *Models, Biological; Motor Activity/drug effects
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 0140-7783 ISBN Medium
Area Expedition Conference
Notes PMID:6125601 Approved no
Call Number refbase @ user @ Serial 1957
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