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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 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 (up) 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 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 (up) 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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Author Dubois, F.; Giraldeau, L.-A.; Hamilton, I.M.; Grant, J.W.A.; Lefebvre, L.
Title Distraction sneakers decrease the expected level of aggression within groups: a game-theoretic model Type Journal Article
Year 2004 Publication The American Naturalist Abbreviated Journal Am Nat
Volume 164 Issue 2 Pages E32-45
Keywords *Aggression; Animals; Behavior, Animal/*physiology; Columbidae/*physiology; Competitive Behavior; Cooperative Behavior; *Game Theory; Hawks/*physiology; Models, Biological
Abstract Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp.
Address Departement des Sciences Biologiques, Universite du Quebec a Montreal, Case postale 8888 Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada. frede_dubois@yahoo.fr
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language (up) Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1537-5323 ISBN Medium
Area Expedition Conference
Notes PMID:15278850 Approved no
Call Number Serial 2130
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Author Dubois, F.; Giraldeau, L.-A.
Title The forager's dilemma: food sharing and food defense as risk-sensitive foraging options Type Journal Article
Year 2003 Publication The American Naturalist Abbreviated Journal Am Nat
Volume 162 Issue 6 Pages 768-779
Keywords Animals; Competitive Behavior/*physiology; *Environment; Feeding Behavior/*physiology; *Game Theory; *Models, Biological; Population Density; Population Dynamics
Abstract Although many variants of the hawk-dove game predict the frequency at which group foraging animals should compete aggressively, none of them can explain why a large number of group foraging animals share food clumps without any overt aggression. One reason for this shortcoming is that hawk-dove games typically consider only a single contest, while most group foraging situations involve opponents that interact repeatedly over discovered food clumps. The present iterated hawk-dove game predicts that in situations that are analogous to a prisoner's dilemma, animals should share the resources without aggression, provided that the number of simultaneously available food clumps is sufficiently large and the number of competitors is relatively small. However, given that the expected gain of an aggressive animal is more variable than the gain expected by nonaggressive individuals, the predicted effect of the number of food items in a clump-clump richness-depends on whether only the mean or both the mean and variability associated with payoffs are considered. More precisely, the deterministic game predicts that aggression should increase with clump richness, whereas the stochastic risk-sensitive game predicts that the frequency of encounters resulting in aggression should peak at intermediate clump richnesses or decrease with increasing clump richness if animals show sensitivity to the variance or coefficient of variation, respectively.
Address Departement des Sciences Biologiques, Universite du Quebec a Montreal, Case postale 8888, Succursale Centre-Ville, Montreal, Quebec H3C 3P8, Canada. fdubois@u-bourgogne.fr
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language (up) Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-0147 ISBN Medium
Area Expedition Conference
Notes PMID:14737714 Approved no
Call Number Serial 2132
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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 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 (up) 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 Kiltie, R.A.; Fan, J.; Laine, A.F.
Title A wavelet-based metric for visual texture discrimination with applications in evolutionary ecology Type Journal Article
Year 1995 Publication Mathematical Biosciences Abbreviated Journal Math Biosci
Volume 126 Issue 1 Pages 21-39
Keywords Animals; Carnivora; *Ecology; Equidae; *Evolution; Humans; Mathematics; Models, Biological; Moths; *Pattern Recognition, Visual; Pigmentation
Abstract Much work on natural and sexual selection is concerned with the conspicuousness of visual patterns (textures) on animal and plant surfaces. Previous attempts by evolutionary biologists to quantify apparency of such textures have involved subjective estimates of conspicuousness or statistical analyses based on transect samples. We present a method based on wavelet analysis that avoids subjectivity and that uses more of the information in image textures than transects do. Like the human visual system for texture discrimination, and probably like that of other vertebrates, this method is based on localized analysis of orientation and frequency components of the patterns composing visual textures. As examples of the metric's utility, we present analyses of crypsis for tigers, zebras, and peppered moth morphs.
Address Department of Zoology, University of Florida, Gainesville
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language (up) Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0025-5564 ISBN Medium
Area Expedition Conference
Notes PMID:7696817 Approved no
Call Number Equine Behaviour @ team @ Serial 2660
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Author Kaplan, A.I.; Borodovskii, M.I.
Title [Alternative animal behavior: a model and its statistical characteristics] Type Journal Article
Year 1989 Publication Nauchnye Doklady Vysshei Shkoly. Biologicheskie Nauki Abbreviated Journal Nauchnye Doki Vyss Shkoly Biol Nauki
Volume Issue 3 Pages 29-32
Keywords Animals; *Behavior, Animal; Cognition; Male; Mathematics; *Models, Biological; *Models, Statistical; Rats; Reinforcement (Psychology)
Abstract The rats' alternative behaviour in T-maze at simultaneous two-sided food refreshment in 13 trials a day during 6 days has been studied. It has been found that in the first testing days the indexes of alternative behaviour of animals correspond to the characteristics of the random alternation. However, on the 5-6th day of testing in the overwhelming majority of rats the true deviation of alternation index above or below than the theoretical values has been revealed. A question on the existence of two strategies of cognitive behaviour alteration and perseveration in rat population is under discussion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Russian Summary Language (up) Original Title Al'ternativnoe povedenie zhivotnykh: model' i statisticheskie kharakteristiki
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0470-4606 ISBN Medium
Area Expedition Conference
Notes PMID:2742929 Approved no
Call Number Equine Behaviour @ team @ Serial 2799
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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 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 (up) 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 Santamaria, S.; Bobbert, M.E.; Back, W.; Barneveld, A.; van Weeren, P.R.
Title Variation in free jumping technique within and among horses with little experience in show jumping Type Journal Article
Year 2004 Publication American Journal of Veterinary Research Abbreviated Journal Am J Vet Res
Volume 65 Issue 7 Pages 938-944
Keywords *Acceleration; Analysis of Variance; Animals; Biomechanics; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Models, Biological; Video Recording
Abstract OBJECTIVE: To quantify variation in the jumping technique within and among young horses with little jumping experience, establish relationships between kinetic and kinematic variables, and identify a limited set of variables characteristic for detecting differences in jumping performance among horses. ANIMALS: Fifteen 4-year-old Dutch Warmblood horses. PROCEDURE: The horses were raised under standardized conditions and trained in accordance with a fixed protocol for a short period. Subsequently, horses were analyzed kinematically during free jumping over a fence with a height of 1.05 m. RESULTS: Within-horse variation in all variables that quantified jumping technique was smaller than variation among horses. However, some horses had less variation than others. Height of the center of gravity (CG) at the apex of the jump ranged from 1.80 to 2.01 m among horses; this variation could be explained by the variation in vertical velocity of the CG at takeoff (r, 0.78). Horses that had higher vertical velocity at takeoff left the ground and landed again farther from the fence, had shorter push-off phases for the forelimbs and hind limbs, and generated greater vertical acceleration of the CG primarily during the hind limb push-off. However, all horses cleared the fence successfully, independent of jumping technique. CONCLUSIONS AND CLINICAL RELEVANCE: Each horse had its own jumping technique. Differences among techniques were characterized by variations in the vertical velocity of the CG at takeoff. It must be determined whether jumping performance later in life can be predicted from observing free jumps of young horses.
Address Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 12, NL-3584 CM Utrecht, The Netherlands
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language (up) Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-9645 ISBN Medium
Area Expedition Conference
Notes PMID:15281652 Approved no
Call Number Equine Behaviour @ team @ Serial 3772
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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 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 (up) 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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