19,923 research outputs found
Plasma metabolites reflect seasonally changing metabolic processes in a long-distance migrant shorebird (Calidris canutus)
Migrant birds have tightly scheduled annual cycles consisting of several distinct life cycle (sub-)stages such as reproduction, migration, moult and overwintering, each of which have specific metabolic requirements (e.g., fattening during migration, protein build-up during moult). This study examines changes in fat and protein metabolism during the annual cycle of body mass and moult over 1.5 years in a captive flock of an arctic-breeding shorebird, the red knot Calidris canutus islandica. 2–5 h after food withdrawal, plasma uric acid levels were still decreasing and β-hydroxy-butyrate levels were low, indicating prolonged catabolism of dietary protein, probably linked with a conversion into lipids. Such a late-resorptive state is achieved much earlier in passerines, but only after several days in penguins and, thus, seems to depend on meal size or mass-specific metabolic rate. Substages of body mass gain and high body mass were characterized by increased plasma triglyceride levels reflecting increased turnover of lipids, and low levels of the ketone body β-hydroxy-butyrate, indicating that the bird is not short of glucose. The high uric acid levels during these substages indicated an increased breakdown of nutritional protein. During moult, plasma triglyceride levels were low, suggesting that lipids were less available than at other times of the year. It is concluded that plasma metabolite levels indicate the metabolic processes related to migratory fuelling and moult and the influence of exogeneous factors.
Jenni Cook Associate Professor, Department of Music - College of Liberal Arts
Professor Cook traveled to Ribeirão-Preto, Brazil, in June of 2012 for a site visit to complete details for a student exchange between the University of São-Paulo in Ribeirão-Preto and UNH. While there, she gave two lectures on Body Mapping, a lecture on Diction for Singers, a Master Class for singers and instrumentalists, and a recital of Brazilian Art Song and Songs by Women Composers. Professor Cook also spent time with her former student Melody Chapin ’10 currently in Brazil on a Fulbright Scholarship to develop an anthology of Brazilian Art Song
Oxidative stress in endurance flight: an unconsidered factor in bird migration
Migrating birds perform extraordinary endurance flights, up to 200 h non-stop, at a very high metabolic rate and while fasting. Such an intense and prolonged physical activity is normally associated with an increased production of reactive oxygen and nitrogen species (RONS) and thus increased risk of oxidative stress. However, up to now it was unknown whether endurance flight evokes oxidative stress. We measured a marker of oxidative damage (protein carbonyls, PCs) and a marker of enzymatic antioxidant capacity (glutathione peroxidase, GPx) in the European robin (Erithacus rubecula), a nocturnal migrant, on its way to the non-breeding grounds. Both markers were significantly higher in European robins caught out of their nocturnal flight than in conspecifics caught during the day while resting. Independently of time of day, both markers showed higher concentrations in individuals with reduced flight muscles. Adults had higher GPx concentrations than first-year birds on their first migration. These results show for the first time that free-flying migrants experience oxidative stress during endurance flight and up-regulate one component of antioxidant capacity. We discuss that avoiding oxidative stress may be an overlooked factor shaping bird migration strategies, e.g. by disfavouring long non-stop flights and an extensive catabolism of the flight muscles
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Philosophy at Cambridge, Newsletter of the Faculty of Philosophy
Philosophy at Cambridge. Newsletter of the Philosophy Faculty. Articles by: Simon Blackburn, 'From the Chairman' ; Philip Pettit, 'Hobbes, Berlin and Freedom' ; Matthew Kramer, 'What is Legal Philosophy?' ; 'A Conversation with Tim Crane' Interviewed by Simon Blackburn ; Alexis Papazoglou, 'The Philosophy of Wine- Review' ; Lubomira Radoilska, 'Autonomy and Mental Health Conference' ; Winston Fletcher, 'The Meaning of Harpic'
From Bison to Cattle: The Ecology of the Southern Plains 1500-1750
Bison made their home on the Southern Plains for millennia. However, their migratory patterns began to shift in the 17th and 18th centuries. My research investigated what caused this drastic shift and how it had far reaching effects on the ecology of the Southern Plains. Using archives from two prominent Catholic priests, I began to piece together why the bison left the Southern Plains. Rather than focus on the Europeans as the main players, I instead focused on the Indigenous peoples, the animals, and the land as the centralized actors in this project. I discovered that the introduction of cattle by the Spanish missions was the leading factor. As the cattle quickly consumed the resources, the bison had to find additional inhabitable spaces. Their swift departure from the Southern Plains resulted in upheaval for the Indigenous inhabitants and the ecology of the Plains themselves
The North is poorer and contributes far less to the national GDP than the South East, but compared to the national pay gap, it is fairer up North.
Ed Miliband recently addressed the subject of pay inequality in a speech at the Resolution Foundation’s launch of the Commission on Living Standards, highlighting the growing gap between the top and bottom wage earners in the country and concluding that the benefits of economic growth are not shared fairly. Jenni Viitanen argues that observations about the way in which economic growth tends to disproportionately benefit a narrow section of the wealthiest in society underscore the question of who and what remain in the shadows of the UK economy.
Are there industrial and agricultural convergence clubs in China?
This paper discusses growth differentials of Chinese provinces geared to agricultural activities and those focusing on industrial production over three decades of economic reform. Following trade theory and endogenous growth theory, we suggest that the fundamental differences between regions arise from their resource allocations at the start of reforms. Thus, capital-abundant regions have tended to specialize in industrial production, while the labor-abundant regions have concentrated on labor-intensive production (agriculture). Many of China's agricultural provinces suffer from oversupplies of labor, which has led large numbers of people to migrate within the country to work in non-farming sectors of economy. We show that provinces with high shares of industrial production (the industrial club) have converged, and that agricultural provinces shifting to industrial production have been catching up to initially industrialized provinces. Provinces that have stayed with an agricultural strategy (the agricultural club) show no evidence of convergence and appear to have been left behind in terms of economic development.growth; agriculture; convergence
Negative brand beliefs and brand usage
This research focuses on consumer brand usage segments and the responses they give to negative attributes in brand image studies. Analysis was conducted across three markets and four approaches for measuring brand beliefs with respondents who were current users, past users or had never tried a brand. The major finding of this study was that past users of a brand consistently have the highest tendency to elicit negative beliefs about brands. Further, those who have never used a brand typically have a lower propensity than current brand users to elicit negative brand beliefs. These results suggest that negative beliefs about a brand are developed as a result of purchase behaviour, rather than as mechanisms to reject a brand prior to purchase. These findings have implications for the role of negative beliefs in consideration of set formation and the trial of a new brand. They also provide insight into the patterns that may be expected when measuring and interpreting negative brand beliefs across different usage groups
Economic Freedom as a Driver for Growth in Transition
This paper reviews the political economy view of economic growth in post-communist economies making the transition to free markets, focusing on the role of economic policy and institutions. We test the hypothesis that better institutions, measured in terms of economic freedom, contribute to growth. The empirical results from the cross-section of transition economies confirm this hypothesis. The paper concludes that non-linearities are present in the growth model and that differences arise depending on how economic well-being is defined.growth; institutions; human capital
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