1,371 research outputs found
The effect of social environment on the development of object play in domestic horse foals
No full textIntroductionFree-ranging horses exist in cohesive social groups that usually consist of one to six mares, their offspring and a stallion. Foals normally have several conspecifics to engage with in social play. Object play is described as “manipulation of an inanimate object with out obvious purpose or reward” (Hughes, 2002). It has been suggested that providing foals with objects at weaning may improve their welfare as a substitute for social play (Mills and Nankervis, 1999). Object play has been reported to substitute for social play in free-roaming dogs (Bekoff, 1974) and marmosets (Jolly, 1985).In the preceding two studies (Hughes, 2002) the authors studied 24 foals. In the first study the foals were from different breeds and kept either socially, or isolated from other foals. The breed of the foals was thought to be an important factor in the large differences in object play behaviour observed between the foals. Therefore, the second study included only Arabian foals. These foals were all kept with at least one other foal. However, individual differences were again observed. The aim of the study reported here was to determine whether social environment affects the display of object play in domestic horse foals within a single breed group.MethodsThree solitary and three socially kept Arabian foals were observed for 30 minutes, once a week from one week to three months of age. All the foals were handled daily by staff at the stud farms. They were maintained at pasture during the day and stabled with their dam at night. Two of the foals were located in the South of England, three were located in South Wales and one was located in the West Midlands of England. The size of the sample was small due to a foot and mouth disease outbreak in the UK, which restricted the type of land that could be visited. During these observations a Jolly Ball (Horseman’s Pride, Ravenna, OH, USA), a large ball (25cm in diameter) with a handle, was placed in the field to ensure that all the foals had the opportunity to manipulate an object. An observer using a hand held video camera filmed the observations. During observations the observer was located in the same field as the foals, but did not interact with them. The videotapes were then viewed and the duration of object play behaviour was timed using a stopwatch and recorded using check sheets.As in previous studies a “boldness” score was devised based on the foals’ interaction with the observer (observer score). Boldness was defined as the willingness of the foals to take risks. The observer score was then compared to an object score, based on the foals’ interaction with objects in the presence of the observer. These scores were as follows: 0 = Foal displays no interest in the object/observer; 1 = Foal orients toward the object/observer; 2 = Foal approaches object/observer; 3 = Foal sniffs object/observer; 4 = Foal makes physical contact with the object/observer.ResultsTotal duration of object manipulation was greater for solitary than social foals. The mean duration during observations for solitary foals was 1.65% versus 1.19% for social foals (Z=-2.04, P<0.05). Total duration of observer interaction was also greater for solitary than social foals. The mean duration during observations for solitary foals was 7.64% versus 2.33% for social foals (Z=-2.70, p<0.01). The solitary kept foals also had significantly higher object and observer scores than the socially kept foals (Object score: Z=-2.51, p<0.05; Observer score: Z=-2.79, p<0.01).DiscussionSolitary kept foals appear to be bolder with objects and people than socially kept foals. This could be because their owners have more time to spend with them and so they receive more handling. However, solitary kept foals also appear to manipulate objects more than socially kept foals. It is possible that the isolated foals are re-directing frustrated social play behaviour toward the object. The lower duration of object manipulation displayed by the socially kept foals may be due to competition between the foals for objects. It could also be that the socially kept foals play with objects less because they are able to engage in social play. In this case the composition of the social group could affect the levels of object manipulation observed.Social environment does appear to have an effect on the levels of object play displayed by foals. Isolated foals appear to manipulate objects for longer than socially kept foals. The initial results of this study indicate that object manipulation and play could be useful as a substitute for social play in socially isolated foals. However, the sample size for this study was small and further studies will be required to increase sample size and therefore reliability.<br/
Shore platforms and mass-movement: A reply
No full textImplicit in Mr Wright's note on shore platforms and mass-movement is a criticism of our findings on the role of mass-movement in shore platform development along the Gisborne coastline, New Zealand (McLean and Davidson, 1968). The lack of explicit criticism makes any reply difficult; we are not rebuked on our own evidence, nor is any fresh evidence presented from the same area to make it necessary for us to change or modify our original views
Katalog der Musikbibliothek Peters ...
No full textClassified, with author indexes.Preface signed: C.F. Peters. Dr. Emil Vogel, bibliothekar.Abth. 1. Theoretische Werke.--Abth. 2. Praktische Werke.Mode of access: Internet
Motion of quantum vortex lines near realistic rough boundaries
No full textWe numerically solve the three--dimensional, time--dependent Gross--Pitaevskii equation to model a superfluid flowing over a realistic rough boundary. Our model for the boundary is based on the atom--force microscope image of a NbTi vibrating wire used to generate turbulence in actual experiments. We find that near the boundary a dense region of quantum vortices is created, which forms a kind of `superfluid boundary layer'
Wave excitations in adjacent vortex filaments
No full textThe interactions of the nearest neighbour vortices are argued to play a significant role in the crossover range of scales that lies between the Kolmogorov-Richardson cascade and the Kelvin wave driven cascade in superfluid turbulence. In this work, we study how a wave excitation (a Kelvin wave or a soliton) on a vortex affects a nearby straight vortex. Our numerical simulations reveal that coherent excitations can hop from one vortex filament to another whilst retaining their coherent properties
Spectral properties of Andreev reflection from quantum turbulence in 3He-B: What do they tell about turbulent fluctuations?
No full textOne of the experimental techniques developed to measure quantum turbulence at low temperatures in 3He-B utilizes the Andreev reflection of thermal quasiparticle excitations from quantized vortices and vortex structures. We present the results of theoretical, numerical, and experimental study of Andreev scattering from quantum turbulence in 3He-B. We analyze the spectral properties of the Andreev reflection and compare these with the spectral properties of superfluid turbulence, and discuss the physical mechanisms responsible for the scaling of spectral densities. Finally, we discuss the relation between our findings and related observables in ordinary turbulence
A Fuzzy-based Scoring Rule for Author Ranking: an alternative to h-index
No full textThe measurement of the quality of research has reached nowadays an increasing interest not only for scientific reasons but also for the critical problem of researchers' ranking, due to the lack of grant assignments. The most commonly used approach is based on the so-called h-index, even if the current literature debated a lot about its pros and cons. This paper, after a brief review of the h-index and of alternative models, focuses on the characterization and the implementation of a modified scoring rule approach by means of a fuzzy inference system a là Sugeno
The role of mass-movement in shore platform development along the Gisborne coastline, New Zealand
No full textTidal shore platforms form a conspicuous part of the coastal scenery north of Gisborne, New Zealand. Some of these platforms are being extended landward under present-day conditions. Present widening results primarily from cliff-retreat by mass-movement. The coincidence in distribution of areas of wave convergence, mass-movement and shore platforms suggests a genetic connection between these marine and subaerial process and response elements. Various types of mass-movement are involved in cliff-retreat, notably slumps, flows, debris slides and soil and rock falls. While the products of such mass-movement forms are removed by wave action, extensive boulder fields on some shore platforms indicate that removal is not always complete. Not all of the shore platforms on this coast are being widened at present. Widening has ceased where active mass-movement is not occurring
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