Behaviour of dairy cows on organic and non-organic farms

There is an increasing number of organic dairy farms in the UK. The aim of this study is to compare behaviour of dairy cows on organic and non-organic farms. Twenty organic and 20 non-organic farms throughout the UK were visited over two winters (2004/05 and 2005/06). Organic and non-organic farms were paired for housing type, herd size, milk production traits and location. The number of cows feeding was counted every fifteen minutes for 4.5 h after new feed was available post morning milking. Behaviour at the feed-face was recorded for 60 minutes and aggressive interactions between cows were quantified. Farm type had no effect on numbers of cows feeding. There were more interactions between cows feeding at open feed-faces compared to head-bale barriers. At open feed-faces, there were more interactions on organic farms than non-organic. It is possible that organic cows were hungrier than non-organic cows after the arrival of new feed

Dissipation and Tunnelling in Quantum Hall Bilayers

We discuss the interplay between transport and intrinsic dissipation in quantum Hall bilayers, within the framework of a simple thought experiment. We compute, for the first time, quantum corrections to the semiclassical dynamics of this system. This allows us to re-interpret tunnelling measurements on these systems. We find a strong peak in the zero-temperature tunnelling current that arises from the decay of Josephson-like oscillations into incoherent charge fluctuations. In the presence of an in-plane field, resonances in the tunnelling current develop an asymmetric lineshape.Comment: 4 pages, 3 figure

Universality in chaotic quantum transport: The concordance between random matrix and semiclassical theories

Electronic transport through chaotic quantum dots exhibits universal, system independent, properties, consistent with random matrix theory. The quantum transport can also be rooted, via the semiclassical approximation, in sums over the classical scattering trajectories. Correlations between such trajectories can be organized diagrammatically and have been shown to yield universal answers for some observables. Here, we develop the general combinatorial treatment of the semiclassical diagrams, through a connection to factorizations of permutations. We show agreement between the semiclassical and random matrix approaches to the moments of the transmission eigenvalues. The result is valid for all moments to all orders of the expansion in inverse channel number for all three main symmetry classes (with and without time reversal symmetry and spin-orbit interaction) and extends to nonlinear statistics. This finally explains the applicability of random matrix theory to chaotic quantum transport in terms of the underlying dynamics as well as providing semiclassical access to the probability density of the transmission eigenvalues.Comment: Refereed version. 5 pages, 4 figure

Modeling Vocal Fold Motion with a New Hydrodynamic Semi-Continuum Model

Vocal fold (VF) motion is a fundamental process in voice production, and is also a challenging problem for direct numerical computation because the VF dynamics depend on nonlinear coupling of air flow with the response of elastic channels (VF), which undergo opening and closing, and induce internal flow separation. A traditional modeling approach makes use of steady flow approximation or Bernoulli's law which is known to be invalid during VF opening. We present a new hydrodynamic semi-continuum system for VF motion. The airflow is modeled by a quasi-one dimensional continuum aerodynamic system, and the VF by a classical lumped two mass system. The reduced flow system contains the Bernoulli's law as a special case, and is derivable from the two dimensional compressible Navier-Stokes equations. Since we do not make steady flow approximation, we are able to capture transients and rapid changes of solutions, e.g. the double pressure peaks at opening and closing stages of VF motion consistent with experimental data. We demonstrate numerically that our system is robust, and models in-vivo VF oscillation more physically. It is also much simpler than a full two-dimensional Navier-Stokes system.Comment: 27 pages,6 figure

Investing in the World's Youth: A Global Initiative

Reviews a decade of the International Youth Foundation's accomplishments in dozens of countries. Looks at the impact on global youth-serving organizations, evolving structures and strategies, challenges and lessons, and emerging trends

I\u27D Give Everything For You

https://digitalcommons.library.umaine.edu/mmb-vp/1736/thumbnail.jp

Predicting Individual Research Productivity: More than a Question of Time

Despite professors’ education and socialization and the significant re- wards they receive for research activities and output, the 80/20 rule seems to apply; that is, there exists a system of stars who produce a disproportionate volume of research such that most research tends to be undertaken by a small percentage of the academy (Erkut, 2002). Although a growing body of research seeks to address this imbalance, studies of research productivity have tended to reveal its institutional and non-behavioural antecedents. As a result, there exists very little re- search that considers the strategies that individuals employ to improve their personal research productivity. This exploratory, questionnaire- based study of a sample of Canadian professors attempts to address this gap by examining the relationship among a number of strategies, what professors report as being their average annual number of publications over the past five years, and their perceptions of their level of research productivity. Not surprisingly, in this study, we found that the amount of time that individuals invested in research activities predicted their level of research productivity. Additionally, strategically focusing one’s research positively influenced journal publication levels, both directly and through its interaction with seeking resources (such as research grants). A strategic focus also positively predicted self-perceived re- search productivity through its interaction with managing ideas. Finally, although the perceived need to free up time from teaching and committee work was negatively related to journal publication levels, it was positively related to perceptions of productivity. Malgré l’importance accordée à la recherche par les universités, la règle des 80/20 s’applique toujours : la majorité de la recherche est menée par une minorité de professeurs (Erkut, 2002). Les études antérieures sur la productivité des chercheurs se sont surtout concentrées sur les antécédents institutionnels, accordant peu d’attention aux stratégies individuelles visant à améliorer la productivité personnelle. Cette étude exploratoire vise à répondre à cette lacune. L’enquête révèle que le nombre d’heures qu’un individu investit dans les activités de recherche est un prédicteur du niveau de productivité. De même, l’adoption d’une stratégie de focalisation des recherches est associée à un plus haut niveau de publication dans les revues scientifiques, en particulier pour les chercheurs qui ont également fait des recherches de financement (par exemple pour des subventions de recherche). En outre, l’interaction entre la focalisation stratégique des recherches et la gestion des idées favorise la perception de soi-même comme un chercheur productif. Enfin, le sentiment de devoir réduire le temps d’enseignement et de service à la collectivité s’est avéré négativement corrélé au niveau de publication dans les revues scientifiques, mais positivement corrélé à la perception de soi comme chercheur productif.Malgré l’importance accordée à la recherche par les universités, la règle des 80/20 s’applique toujours : la majorité de la recherche est menée par une minorité de professeurs (Erkut, 2002). Les études antérieures sur la productivité des chercheurs se sont surtout concentrées sur les antécédents institutionnels, accordant peu d’attention aux stratégies individuelles visant à améliorer la productivité personnelle. Cette étude exploratoire vise à répondre à cette lacune. L’enquête révèle que le nombre d’heures qu’un individu investit dans les activités de recherche est un prédicteur du niveau de productivité. De même, l’adoption d’une stratégie de focalisation des recherches est associée à un plus haut niveau de publication dans les revues scientifi ques, en particulier pour les chercheurs qui ont également fait des recherches de financement (par exemple pour des subventions de recherche). En outre, l’interaction entre la focalisation stratégique des recherches et la gestion des idées favorise la perception de soi-même comme un chercheur productif. Enfin, le sentiment de devoir réduire le temps d’enseignement et de service à la collectivité s’est avéré négativement corrélé au niveau de publication dans les revues scientifiques, mais positivement corrélé à la perception de soi comme chercheur productif