|   | 
Details
   web
Records
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 Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 0021-9673 ISBN Medium
Area Expedition Conference
Notes PMID:17196214 Approved no
Call Number Serial 1842
Permanent link to this record
 

 
Author Suzuki, Y.; Toquenaga, Y.
Title Effects of information and group structure on evolution of altruism: analysis of two-score model by covariance and contextual analyses Type Journal Article
Year 2005 Publication Journal of theoretical biology Abbreviated Journal J. Theor. Biol.
Volume 232 Issue 2 Pages 191-201
Keywords *Altruism; Analysis of Variance; *Communication; Cooperative Behavior; *Evolution; Game Theory; *Group Structure; Humans; Models, Genetic; Models, Psychological; Selection (Genetics); Trust
Abstract An altruistic individual has to gamble on cooperation to a stranger because it does not know whether the stranger is trustworthy before direct interaction. Nowak and Sigmund (Nature 393 (1998a) 573; J. Theor. Biol. 194 (1998b) 561) presented a new theoretical framework of indirect reciprocal altruism by image scoring game where all individuals are informed about a partner's behavior from its image score without direct interaction. Interestingly, in a simplified version of the image scoring game, the evolutionarily stability condition for altruism became a similar form of Hamilton's rule, i.e. inequality that the probability of getting correct information is more than the ratio of cost to benefit. Since the Hamilton's rule was derived by evolutionarily stable analysis, the evolutionary meaning of the probability of getting correct information has not been clearly examined in terms of kin and group selection. In this study, we applied covariance analysis to the two-score model for deriving the Hamilton's rule. We confirmed that the probability of getting correct information was proportional to the bias of altruistic interactions caused by using information about a partner's image score. The Hamilton's rule was dependent on the number of game bouts even though the information reduced the risk of cooperation to selfish one at the first encounter. In addition, we incorporated group structure to the two-score model to examine whether the probability of getting correct information affect selection for altruism by group selection. We calculated a Hamilton's rule of group selection by contextual analysis. Group selection is very effective when either the probability of getting correct information or that of future interaction, or both are low. The two Hamilton's rules derived by covariance and contextual analyses demonstrated the effects of information and group structure on the evolution of altruism. We inferred that information about a partner's behavior and group structure can produce flexible pathways for the evolution of altruism.
Address Integrative Environmental Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Ten-Nou-Dai, Tsukuba, Ibaraki 305-8572, Japan. yukari@pe.ies.life.tsukuba.ac.jp
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 (up) 0022-5193 ISBN Medium
Area Expedition Conference
Notes PMID:15530489 Approved no
Call Number refbase @ user @ Serial 556
Permanent link to this record
 

 
Author de Waal, F.B.M.; Dindo, M.; Freeman, C.A.; Hall, M.J.
Title The monkey in the mirror: hardly a stranger Type Journal Article
Year 2005 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc. Natl. Acad. Sci. U.S.A.
Volume 102 Issue 32 Pages 11140-11147
Keywords Analysis of Variance; Animals; Cebus/*physiology; *Discrimination (Psychology); Empathy; Female; Male; Observation; *Recognition (Psychology); *Self Concept; Sex Factors
Abstract It is widely assumed that monkeys see a stranger in the mirror, whereas apes and humans recognize themselves. In this study, we question the former assumption by using a detailed comparison of how monkeys respond to mirrors versus live individuals. Eight adult female and six adult male brown capuchin monkeys (Cebus apella) were exposed twice to three conditions: (i) a familiar same-sex partner, (ii) an unfamiliar same-sex partner, and (iii) a mirror. Females showed more eye contact and friendly behavior and fewer signs of anxiety in front of a mirror than they did when exposed to an unfamiliar partner. Males showed greater ambiguity, but they too reacted differently to mirrors and strangers. Discrimination between conditions was immediate, and blind coders were able to tell the difference between monkeys under the three conditions. Capuchins thus seem to recognize their reflection in the mirror as special, and they may not confuse it with an actual conspecific. Possibly, they reach a level of self-other distinction intermediate between seeing their mirror image as other and recognizing it as self.
Address Living Links Center, Emory University, Atlanta, GA 30322, USA. dewaal@emory.edu
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 (up) 0027-8424 ISBN Medium
Area Expedition Conference
Notes PMID:16055557 Approved no
Call Number refbase @ user @ Serial 164
Permanent link to this record
 

 
Author Moses, S.N.; Villate, C.; Ryan, J.D.
Title An investigation of learning strategy supporting transitive inference performance in humans compared to other species Type Journal Article
Year 2006 Publication Neuropsychologia Abbreviated Journal Neuropsychologia
Volume 44 Issue 8 Pages 1370-1387
Keywords Adult; Analysis of Variance; Association Learning/*physiology; *Cognition; *Concept Formation; Female; Humans; *Logic; Male; Pattern Recognition, Visual/physiology; Photic Stimulation/methods; Reaction Time/physiology
Abstract Generalizations about neural function are often drawn from non-human animal models to human cognition, however, the assumption of cross-species conservation may sometimes be invalid. Humans may use different strategies mediated by alternative structures, or similar structures may operate differently within the context of the human brain. The transitive inference problem, considered a hallmark of logical reasoning, can be solved by non-human species via associative learning rather than logic. We tested whether humans use similar strategies to other species for transitive inference. Results are crucial for evaluating the validity of widely accepted assumptions of similar neural substrates underlying performance in humans and other animals. Here we show that successful transitive inference in humans is unrelated to use of associative learning strategies and is associated with ability to report the hierarchical relationship among stimuli. Our work stipulates that cross-species generalizations must be interpreted cautiously, since performance on the same task may be mediated by different strategies and/or neural systems.
Address Rotman Research Institute, Baycrest Centre for Geriatric Care, Toronto, Canada. smoses@rotman-baycrest.on.ca
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 (up) 0028-3932 ISBN Medium
Area Expedition Conference
Notes PMID:16503340 Approved no
Call Number refbase @ user @ Serial 153
Permanent link to this record
 

 
Author Sundaresan, S.R.; Fischhoff, I.R.; Dushoff, J.; Rubenstein, D.I.
Title Network metrics reveal differences in social organization between two fission-fusion species, Grevy's zebra and onager Type Journal Article
Year 2007 Publication Oecologia Abbreviated Journal Oecologia
Volume 151 Issue 1 Pages 140-149
Keywords Analysis of Variance; Animals; Behavior, Animal/*physiology; *Environment; Equidae/*physiology; Female; India; Kenya; Male; *Models, Theoretical; *Social Behavior; *Social Environment
Abstract For species in which group membership frequently changes, it has been a challenge to characterize variation in individual interactions and social structure. Quantifying this variation is necessary to test hypotheses about ecological determinants of social patterns and to make predictions about how group dynamics affect the development of cooperative relationships and transmission processes. Network models have recently become popular for analyzing individual contacts within a population context. We use network metrics to compare populations of Grevy's zebra (Equus grevyi) and onagers (Equus hemionus khur). These closely related equids, previously described as having the same social system, inhabit environments differing in the distribution of food, water, and predators. Grevy's zebra and onagers are one example of many sets of coarsely similar fission-fusion species and populations, observed elsewhere in other ungulates, primates, and cetaceans. Our analysis of the population association networks reveals contrasts consistent with their distinctive environments. Grevy's zebra individuals are more selective in their association choices. Grevy's zebra form stable cliques, while onager associations are more fluid. We find evidence that females associate assortatively by reproductive state in Grevy's zebra but not in onagers. The current approach demonstrates the utility of network metrics for identifying fine-grained variation among individuals and populations in association patterns. From our analysis, we can make testable predictions about behavioral mechanisms underlying social structure and its effects on transmission processes.
Address Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA. ssundare@princeton.edu
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 (up) 0029-8549 ISBN Medium
Area Expedition Conference
Notes PMID:16964497 Approved no
Call Number Serial 1863
Permanent link to this record
 

 
Author Brosnan, S.F.; de Waal, F.B.M.
Title Responses to a simple barter task in chimpanzees, Pan troglodytes Type Journal Article
Year 2005 Publication Primates Abbreviated Journal Primates
Volume 46 Issue 3 Pages 173-182
Keywords Analysis of Variance; Animals; Choice Behavior/*physiology; Conditioning (Psychology)/physiology; Learning/*physiology; Pan troglodytes/*physiology; Reward; Sex Factors; *Social Behavior; *Token Economy
Abstract Chimpanzees (Pan troglodytes) frequently participate in social exchange involving multiple goods and services of variable value, yet they have not been tested in a formalized situation to see whether they can barter using multiple tokens and rewards. We set up a simple barter economy with two tokens and two associated rewards and tested chimpanzees on their ability to obtain rewards by returning the matching token in situations in which their access to tokens was unlimited or limited. Chimpanzees easily learned to associate value with the tokens, as expected, and did barter, but followed a simple strategy of favoring the higher-value token, regardless of the reward proffered, instead of a more complex but more effective strategy of returning the token that matched the reward. This response is similar to that shown by capuchin monkeys in our previous study. We speculate that this response, while not ideal, may be sufficient to allow for stability of the social exchange system in these primates, and that the importance of social barter to both species may have led to this convergence of strategies.
Address Living Links, Yerkes National Primate Research Center, Atlanta, GA 30322, USA. sbrosna@emory.edu
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 (up) 0032-8332 ISBN Medium
Area Expedition Conference
Notes PMID:15824938 Approved no
Call Number refbase @ user @ Serial 167
Permanent link to this record
 

 
Author Murai, C.; Tomonaga, M.; Kamegai, K.; Terazawa, N.; Yamaguchi, M.K.
Title Do infant Japanese macaques ( Macaca fuscata) categorize objects without specific training? Type Journal Article
Year 2004 Publication Primates Abbreviated Journal Primates
Volume 45 Issue 1 Pages 1-6
Keywords Analysis of Variance; Animals; *Cognition; *Concept Formation; *Generalization, Stimulus; Japan; Macaca/*psychology; Male
Abstract In the present study, we examined whether infant Japanese macaques categorize objects without any training, using a similar technique also used with human infants (the paired-preference method). During the familiarization phase, subjects were presented twice with two pairs of different objects from one global-level category. During the test phase, they were presented twice with a pair consisting of a novel familiar-category object and a novel global-level category object. The subjects were tested with three global-level categories (animal, furniture, and vehicle). It was found that they showed significant novelty preferences as a whole, indicating that they processed similarities between familiarization objects and novel familiar-category objects. These results suggest that subjects responded distinctively to objects without training, indicating the possibility that infant macaques possess the capacity for categorization.
Address Department of Psychology, Graduate School of Letters, Kyoto University, Sakyo, Kyoto 606-8501, Japan. cmurai@bun.kyoto-u.ac.jp
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 (up) 0032-8332 ISBN Medium
Area Expedition Conference
Notes PMID:14505179 Approved no
Call Number Equine Behaviour @ team @ Serial 2813
Permanent link to this record
 

 
Author Zentall, T.R.; Kaiser, D.H.; Clement, T.S.; Weaver, J.E.; Campbell, G.
Title Presence/absence-sample matching by pigeons: divergent retention functions may result from the similarity of behavior during the absence sample and the retention interval Type Journal Article
Year 2000 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process
Volume 26 Issue 3 Pages 294-304
Keywords Analysis of Variance; Animals; *Behavior, Animal; *Choice Behavior; *Columbidae; *Conditioning, Operant; Cues
Abstract Divergent choose-absence retention functions typically found in pigeons following presence/absence-sample matching have been attributed to the development of a single-code/default coding strategy. However, such effects may result from adventitious differential responding to the samples. In Experiment 1, retention functions were divergent only when differential sample responding could serve as the basis for comparison choice. In Experiment 2, when pecking did not occur during the retention interval, a choose-absence bias was found, but when pecking occurred during the retention interval, a choose-presence bias resulted. In Experiment 3, positive transfer was found when a stimulus associated with the absence of pecking replaced the absence sample but not when a stimulus associated with pecking replaced the presence sample. Thus, presence/absence-sample matching may not encourage the development of a single-code/default coding strategy in pigeons.
Address Department of Psychology, University of Kentucky, Lexington 40506, USA. zentall@pop.uky.edu
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 (up) 0097-7403 ISBN Medium
Area Expedition Conference
Notes PMID:10913994 Approved no
Call Number refbase @ user @ Serial 247
Permanent link to this record
 

 
Author Shettleworth, S.J.; Plowright, C.M.
Title How pigeons estimate rates of prey encounter Type Journal Article
Year 1992 Publication Journal of experimental psychology. Animal behavior processes Abbreviated Journal J Exp Psychol Anim Behav Process
Volume 18 Issue 3 Pages 219-235
Keywords Analysis of Variance; Animals; *Appetitive Behavior; Columbidae; Conditioning, Operant; Food Preferences/*psychology; Motivation; *Predatory Behavior; *Probability Learning; *Reinforcement Schedule; Social Environment
Abstract Pigeons were trained on operant schedules simulating successive encounters with prey items. When items were encountered on variable-interval schedules, birds were more likely to accept a poor item (long delay to food) the longer they had just searched, as if they were averaging prey density over a short memory window (Experiment 1). Responding as if the immediate future would be like the immediate past was reversed when a short search predicted a long search next time (Experiment 2). Experience with different degrees of environmental predictability appeared to change the length of the memory window (Experiment 3). The results may reflect linear waiting (Higa, Wynne, & Staddon, 1991), but they differ in some respects. The findings have implications for possible mechanisms of adjusting behavior to current reinforcement conditions.
Address Department of Psychology, University of Toronto, Ontario, Canada
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 (up) 0097-7403 ISBN Medium
Area Expedition Conference
Notes PMID:1619391 Approved no
Call Number refbase @ user @ Serial 382
Permanent link to this record
 

 
Author Milgram, N.W.; Head, E.; Muggenburg, B.; Holowachuk, D.; Murphey, H.; Estrada, J.; Ikeda-Douglas, C.J.; Zicker, S.C.; Cotman, C.W.
Title Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy Type Journal Article
Year 2002 Publication Neuroscience and Biobehavioral Reviews Abbreviated Journal Neurosci Biobehav Rev
Volume 26 Issue 6 Pages 679-695
Keywords Age Factors; Aging/*physiology; Analysis of Variance; Animals; Antioxidants/*pharmacology; Blood Chemical Analysis/methods; Cognition/*physiology; *Diet; Discrimination Learning/*drug effects/*physiology; Distance Perception/drug effects/physiology; Dogs/physiology; Female; Male; Psychomotor Performance/physiology; Retention (Psychology)/drug effects/physiology; Spatial Behavior/*drug effects/*physiology; Task Performance and Analysis; Time Factors; Vitamin E/blood
Abstract The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition.
Address Life Science Division, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ont., Canada M1C 1A4. milgram@psych.utoronto.ca
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 (up) 0149-7634 ISBN Medium
Area Expedition Conference
Notes PMID:12479842 Approved no
Call Number Equine Behaviour @ team @ Serial 2806
Permanent link to this record