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Nakagawa, S. (2004). A farewell to Bonferroni: the problems of low statistical power and publication bias. beheco, 15(6), 1044–1045.
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Maury, M., Murphy, K., Kumar, S., Mauerer, A., & Lee, G. (2005). Spray-drying of proteins: effects of sorbitol and trehalose on aggregation and FT-IR amide I spectrum of an immunoglobulin G. Eur. J. Pharm. Biopharm., 59(2), 251–261.
Abstract: An immunoglobulin G (IgG) was spray-dried on a Büchi 190 laboratory spray-dryer at inlet and outlet air temperatures of 130 and 190°C, respectively. The IgG solution contains initially 115mg/ml IgG plus 50mg/ml sorbitol. After dialysis, at least 80% of low molecular weight component was removed. After spray-drying the dialyzed IgG and immediate redissolution of the powder, an increase in aggregates from 1 to 17% occurred. A major shift towards increase β-sheet structure was detected in the spray-dried solid, which, however, reverted to native structure on redissolution of the powder. A correlation between aggregation determined by size exclusion chromatography and alterations in secondary structure determined by Fourier transformation infra-red spectroscopy could not therefore be established. On spray-drying a non-dialyzed, sorbitol-containing IgG only some 0.7% aggregates were formed. The sorbitol is therefore evidently able to stabilize partially the IgG during the process of spray-drying. Addition of trehalose to the liquid feed produced quantitatively the same stabilizing action on the IgG during spray-drying as did the sorbitol. This finding again points towards a water replacement stabilization mechanism. The IgG spray-dried powder prepared from the dialyzed liquid feed showed continued substantial aggregation on dry storage at 25°C. This was substantially less in the non-dialyzed, sorbitol-containing spray-dried powder. Addition of trehalose to both dialyzed and non-dialyzed system produced substantial improvement in storage stability and reduction in aggregate formation in storage. The quantitative stabilizing effect of the trehalose was only slightly higher than that of the sorbitol. Taken together, these results indicate that both the sorbitol and trehalose stabilize the IgG primarily by a water replacement mechanism rather than by glassy immobilization. The relevance of this work is its questioning of the importance of the usually considered dominance of glassy stabilization of protein in dried systems of high glass transition temperature, such as trehalose. The low glass transition temperature sorbitol produces almost equal process and storage stability in this case.
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Lonsdorf, E. V. (2005). Sex differences in the development of termite-fishing skills in the wild chimpanzees, Pan troglodytes schweinfurthii, of Gombe National Park, Tanzania. Anim. Behav., 70(3), 673–683.
Abstract: By the age of 5.5 years, all of the young chimpanzees of Gombe National Park have acquired a skill known as 'termite fishing'. Termite fishing involves inserting a flexible tool made from vegetation into a termite mound and extracting the termites that attack and cling to the tool. Although tool use is a well-known phenomenon in chimpanzees, little is known about how such skills develop in the wild. Prior studies have found adult sex differences in frequency, duration and efficiency of tool-using tasks, with females scoring higher on all measures. To investigate whether these sex differences occurred in youngsters, I performed a 4-year longitudinal field study during which I observed and videotaped young chimpanzees' development of the termite-fishing behaviour. Critical elements of the skill included identifying a hole, making a tool, inserting a tool into a hole and extracting termites. These elements appeared in the same order during the development of all subjects, but females typically peaked at least a year earlier than males in their performance of the skills that precede termite fishing. In addition, young females successfully termite-fished an average of 27 months earlier than young males and were more proficient at the skill after acquisition had occurred. Furthermore, the techniques of female offspring closely resembled those of their mothers whereas the techniques of male offspring did not, suggesting that the process by which termite fishing is learned differs for male and female chimpanzees.
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Pongrácz, P., Miklósi, Á., Vida, V., & Csányi, V. (2005). The pet dogs ability for learning from a human demonstrator in a detour task is independent from the breed and age. Appl. Anim. Behav. Sci., 90(3), 309–323.
Abstract: There are many indications and much practical knowledge about the different tasks which various breeds of dogs are selected for. Correspondingly these different breeds are known to possess different physical and mental abilities. We hypothesized that commonly kept breeds will show differences in their problem solving ability in a detour task around a V-shaped fence, and also, that breed differences will affect their learning ability from a human demonstrator, who demonstrates a detour around the fence. Subjects were recruited in Hungarian pet dog schools. We compared the results of the 10 most common breeds in our sample when they were tested in the detour task without human demonstration. There was no significant difference between the latencies of detour, however, there was a trend that German Shepherd dogs were the quickest and Giant Schnauzers were the slowest in this test. For testing the social learning ability of dogs we formed three breed groups (“utility”, “shepherd” and “hunting”). There were no significant differences between these, all the breed groups learned equally well from the human demonstrator. However, we found that dogs belonging to the “shepherd” group looked back more frequently to their owner than the dogs in the “hunting” group. Further, we have found that the age of pet dogs did not affect their social learning ability in the detour task. Our results showed that the pet status of a dog has probably a stronger effect on its cognitive performance and human related behaviour than its age or breed. These results emphasize that socialization and common activities with the dog might overcome the possible breed differences, if we give the dogs common problem solving, or social learning tasks.
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Murphy, J., & Arkins, S. (2006). Laterality and visuo-spatial ability in the equine: Functional measures of sport horse selection? BSAP Occasional Publication, 35, 159–170.
Abstract: Laterality in any organism or species can be manifest as morphological, sensory and functional degrees of asymmetry such as hemispheric dominance, handedness or sidedness and other motor functional behaviours and as such is equally important in equitation. The influence of the horses' sex on both the direction and the degree of the laterality was explored within and between 4 experimental procedures in the 1st study. The findings showed that the direction, but not the degree of idiosyncratic motor preference in the horses was strongly sex-related. Male horses exhibited significantly more left lateralized responses and female horses exhibited significantly more right lateralized responses. Visuo-spatial ability is also likely to be important in the performance horse. In many species, moderate to large differences in visuo-spatial ability have been reported between the sexes, with superior visuo-spatial ability being reported in males of all species investigated to date. As no known studies had addressed visuo-spatial ability in the equine, the objective of the 2nd study, was to determine if visuo-spatial ability differed between male and female horses. The results produced the first behavioural demonstration of superior visuo-spatial ability in male horses, similar to that reported in other species. There is evidence to suggest that visuospatial ability and motor laterality are associated with cerebral hemispheric asymmetry and may be intrinsically linked. Brain development and laterality have also been associated with hair patterning, and, in a 3rd study we attempted to identify predictors of lateral bias in motor behaviour in horses. We investigated the relationship between the direction of facial hair whorl rotation and the incidence/direction of laterality in the horse. The findings suggest that direction of facial hair whorl rotation may be a useful indicator of lateralised motor behavioural preferences in the horse. We then attempted to establish if laterality was evident at birth in a 4th study, where we explored if neonatal foals exhibited lateralised patterns during and immediately post the birthing process that were correlated with their facial hair whorl patterns. The results showed a significant association between the sex of the foal and the choice of foreleg presented initially during 2nd stage parturition. Significantly more colt foals led with the left foreleg and significantly more filly foals led with the right foreleg than expected purely by random and the behaviour was correlated with facial hair whorl patterns. The findings also suggest that lateralisation in the horse is determined in utero as has also been shown in humans. Comparisons of wholly intact male and female horses are warranted as they might elucidate additional linkages between motor behaviour, visuo-spatial ability and brain organisation and development in the horse. Further research in this area could lead to more appropriate competition conditions (better fence design/construction on cross-country tracks) and so eliminate unnecessary levels of risk associated with many equestrian sports.
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Kuczaj, S. A., Makecha, R., Trone, M., Paulos, R. D., & Ramos, J. A. (2006). Role of Peers in Cultural Innovation and Cultural Transmission: Evidence from the Play of Dolphin Calves. Int. J. Comp. Psychol, 19(2), 223–240.
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Bonin, S. J., Clayton, H. M., Lanovaz, J. L., & Johnston, T. (2007). Comparison of mandibular motion in horses chewing hay and pellets. Equine Vet. J., 39(3), 258–262.
Abstract: Summary Reasons for performing study: Previous studies have suggested that temporomandibular joint (TMJ) kinematics depend on the type of food being masticated, but accurate measurements of TMJ motion in horses chewing different feeds have not been published. Hypothesis: The temporomandibular joint has a larger range of motion when horses chew hay compared to pellets. Methods: An optical motion capture system was used to track skin markers on the skull and mandible of 7 horses as they chewed hay and pellets. A virtual marker was created on the midline between the mandibles at the level of the 4th premolar teeth to represent the overall motion of the mandible relative to the skull during the chewing cycle. Results: Frequency of the chewing cycles was lower for hay than for pellets. Excursions of the virtual mandibular marker were significantly larger in all 3 directions when chewing hay compared to pellets. The mean velocity of the virtual mandibular marker during the chewing cycle was the same when chewing the 2 feeds. Conclusions: The range of mediolateral displacement of the mandible was sufficient to give full occlusal contact of the upper and lower dental arcades when chewing hay but not when chewing pellets. Potential relevance: These findings support the suggestion that horses receiving a diet high in concentrate feeds may require more frequent dental prophylactic examinations and treatments to avoid the development of dental irregularities associated with smaller mandibular excursions during chewing.
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Giraldeau, L. - A., Lefebvre, L., & Morand-Ferron, J. (2007). Can a restrictive definition lead to biases and tautologies? Behav. Brain Sci., 30(4), 411–412.
Abstract: We argue that the operational definition proposed by Ramsey et al. does not represent a significant improvement for students of innovation, because it is so restrictive that it might actually prevent the testing of hypotheses on the relationships between innovation, ecology, evolution, culture, and intelligence. To avoid tautological thinking, we need to use an operational definition that is taxonomically unbiased and neutral with respect to the hypotheses to be tested.
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Wotschikowsky, U. (2007). Wölfe und Jäger in der Oberlausitz. Broschüre, Freundeskreis freilebender Wölfe, .
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Versace, E., Morgante, M., Pulina, G., & Vallortigara, G. (2007). Behavioural lateralization in sheep (Ovis aries). Behav. Brain. Res., 184(1), 72–80.
Abstract: This study investigates behavioural lateralization in sheep and lambs of different ages. A flock was tested in a task in which the animals were facing an obstacle and should avoid it on either the right or left side to rejoin flock-mates (adult sheep) or their mothers (lambs). A bias for avoiding the obstacle on the right side was observed, with lambs apparently being more lateralized than sheep. This right bias was tentatively associated with the left-hemifield laterality in familiar faces recognition which has been documented in this species. Differences between adult sheep and lambs were likely to be due to differences in social reinstatement motivation elicited by different stimuli (flock-mates or mothers) at different ages. Preferential use of the forelegs to step on a wood-board and direction of jaw movement during rumination was also tested in adult animals. No population bias nor individual-level lateralization was observed for use of the forelegs. At the same time, however, there was a large number of animals showing individual-level lateralization for the direction of jaw movement during rumination even though there was no population bias. These findings highlight that within the same species individual- and population-level lateralization can be observed in different tasks. Moreover, the results fit the general hypothesis that population-level asymmetries are more likely to occur in tasks that require social coordination among behaviourally asymmetric individuals.
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