32 research outputs found
Variation in the chemical composition of adipose tissue of three species of ursids
No full textThe relationship between the water content and lipid content of adipose tissue was compared between 25 polar bears (Ursus maritimus) and 25 black bears (Ursus americanus) to determine if it was affected by species differences in the fatty-acid composition of adipose tissue. The adipose tissue of polar bears had a lower water content and a higher proportion of long-chain fatty acids than did the adipose tissue of black bears, when compared at equal lipid content. The relationship between the body water and lipid contents was also compared among 11 polar bears, 18 black bears, and 6 brown bears (Ursus arctos) to determine if this relationship could be affected by species differences in the relationship between the water and lipid contents of adipose tissue. The body-water content in marine (polar) bears was less than that in terrestrial (black and brown) bears, and the differences in body-water content between the two groups became more apparent as the body-lipid content increased. These results suggest that the fatty-acid composition of adipose tissue can affect the body-water content, especially in fat bears. These findings have implications for the use of isotope-dilution models to predict body composition in bears.</jats:p
Serum corticosteroid binding globulin expression is modulated by fasting in polar bears (Ursus maritimus)
No full textComparison of methanol and isopropanol as wash solvents for determination of hair cortisol concentration in grizzly bears and polar bears
No full textMethodological differences among laboratories are recognized as significant sources of variation in quantification of hair cortisol concentration (HCC). An important step in processing hair, particularly when collected from wildlife, is the choice of solvent used to remove or “wash” external hair shaft cortisol prior to quantification of HCC. The present study systematically compared methanol and isopropanol as wash solvents for their efficiency at removing external cortisol without extracting internal hair shaft cortisol in samples collected from free-ranging grizzly bears and polar bears. Cortisol concentrations in solvents and hair were determined in each of one to eight washes of hair with each solvent independently.
• There were no significant decreases in internal hair shaft cortisol among all eight washes for either solvent, although methanol removed detectable hair surface cortisol after one wash in grizzly bear hair whereas hair surface cortisol was detected in all eight isopropanol washes.
• There were no significant differences in polar bear HCC washed one to eight times with either solvent, but grizzly bear HCC was significantly greater in hair washed with isopropanol compared to methanol.
• There were significant differences in HCC quantified using different commercial ELISA kits commonly used for HCC determinations
Trends in body condition in polar bears (Ursus maritimus) from the Southern Hudson Bay subpopulation in relation to changes in sea ice
Get PDFSea ice is declining over much of the Arctic. In Hudson Bay the ice melts completely each summer, and advances in break-up have resulted in longer ice-free seasons. Consequently, earlier break-up is implicated in declines in body condition, survival, and abundance of polar bears (Ursus maritimus Phipps, 1774) in the Western Hudson Bay (WH) subpopulation. We hypothesised that similar patterns would be evident in the neighbouring Southern Hudson Bay (SH) subpopulation. We examined trends 1980–2012 in break-up and freeze-up dates within the entire SH management unit and within smaller coastal break-up and freeze-up zones. We examined trends in body condition for 900 bears captured during 1984–1986, 2000–2005, and 2007–2009 and hypothesised that body condition would be correlated with duration of sea ice. The ice-free season in SH increased by about 30 days 1980–2012. Body condition declined in all age and sex classes, but the decline was less for cubs than for other social classes. If trends towards a longer ice-free season continue in the future, further declines in body condition and survival rates are likely, and ultimately declines in abundance will occur in the SH subpopulation.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Decentralization : the way forward for rural development?
Get PDFSpecial strategies are needed to address the widespread incidence of rural poverty in developing countries, but initiatives aimed at improving the rural standard of living have not consistently reduced poverty. The author examines the rationale for a specific rural focus in poverty reduction programs and reviews recent attempts to encourage rural development. He discusses the role decentralization could play in rural development programs and analyzes recent efforts to implement decentralized rural development programs. The author concludes that although decentralization initiatives have a long history, much more needs to be understood about various components of decentralization before sound advice can be given to policymakers. He suggests a conceptual model - based on a"souffle"theory of decentralization - that incorporates the essential elements of political, fiscal, and institutional decentralization as they related to rural development outcomes. Like a souffle that requires just the right combination of milk, eggs, and heat to rise, a successful program of decentralization must include just the right combination of political, fiscal, and institutional elements to improve rural development outcomes.Economic Theory&Research,Decentralization,Agricultural Knowledge&Information Systems,Environmental Economics&Policies,Regional Rural Development,Economic Theory&Research,Environmental Economics&Policies,Regional Rural Development,Poverty Assessment,Agricultural Knowledge&Information Systems
Electroactive polymers from β-substituted thiophenes
Get PDFThe work reported in this thesis can be broken down into three main areas. The first describes the synthesis of a series of β-substituted thiophenes bearing long, lipophilic chains (either ether, polyether or amido in nature). Cyclic voltammetry studies on the monomers revealed their oxidation potential but did not prove to be a successful method of electropolymerisation. This was achieved using constant current electrolysis and further studies involving FTIR, ESCA and SEM were carried out on the most highly conducting polymer. This polymer was also solution processible in its conducting form. The second area also describes the synthesis of a series of β-substituted thiophenes, but this time the pendant side group consists of bulky phenoxy moieties (liquid crystals, phenol ethers and aminophenol ethers). In this case the cyclic voltammetry studies carried out did appear to provide a successful means of generating polymers. Finally, the synthesis of a series of β-substituted thiophenes bearing pendant macrocyclic substituents (an N-0-5 cycle, an oxo-cyclam and a 14-0-4 cycle) are described. Their cyclic voltammetry behaviour is reported in detail and the results of experiments to determine metal ion selectivity is also described, in the case of the 14-0-4 cycle
Talking tails : quantifying the development of tail biting in pigs
No full textTail biting is an adverse behaviour characterised by manipulation of a pig’s tail by another pig resulting in tail damage and a possible tail biting outbreak. Tail biting is a common problem in the pig husbandry causing economic losses and reduced animal welfare worldwide. To prevent tail biting, the majority of newborn piglets are tail docked, a procedure which is not only painful but generates more and more public concern. This emphasizes the need to prevent the occurrences of tail biting without having to dock a pig’s tail. So far, research focused mainly on the risk factors that can induce tail biting. However, the way a tail biting outbreak evolves in a group of pigs (the ‘aetiology’) is still poorly understood. For that reason, the main aim of this thesis was to gain more insight in the aetiology of a tail biting outbreak. This will not only enhance our understanding of the current preventive and curative treatments of tail biting, but can also generate more effective measures to prevent, predict and counteract a tail biting outbreak. Therefore, the development of tail biting behaviour and tail damage was studied in relation to preventive and curative measures, group composition and indicators for an upcoming tail biting outbreak. The results showed that the provision of twice daily a handful of long straw strongly reduced tail biting. Furthermore, this measure was also effective in counteracting an ongoing tail biting outbreak (an outbreak was defined as the first day with a minimum of one piglet with a tail wound or two piglets with bite marks in a pen), although this outbreak could not be totally eliminated. In pens without straw almost all pigs performed and received tail biting behaviour at low levels prior to a tail biting outbreak. However, considerable variation in tail biting behaviour between pigs was found. In most pens one or a few pigs could be identified as pronounced biters prior to the tail biting outbreak. Although less clear, often one or a few pigs could similarly be identified as pronounced victims. In mixed-sex pens male pigs developed tail damage most rapidly, while in single-sex pens the quickest tail damage development was found in all-female groups. These results indicate that female pigs are more likely to become biters and male pigs are more likely to become victims. More detailed study of pronounced biters and victims showed that prior to a tail biting outbreak, biters not only directed more of their biting behaviour to their penmates’ tail, but also to the enrichment device. Victims were the heavier pigs in the pen and tended to be more often male and more restless preceding an outbreak. Victims also performed more aggressive behaviour, while biters tended to receive more aggressive behaviour. Furthermore, it was found that tail posture is a predictor for tail damage. Pigs with their tail between the legs had a higher chance of tail damage 2-3 days later. Based on the results of this research an aetiology model of a tail biting outbreak was developed. Subsequently practical suggestions were given to prevent (e.g. providing effective environmental enrichment), predict (e.g. observing the pigs’ tail posture) and counteract (e.g. removing the biter) a tail biting outbreak. This provides opportunities to omit tail docking without the negative consequence of tail biting. <br/
On shoplifting and tax fraud: An action-theoretic analysis of crime
Get PDFThe article evaluates different theories of action in the area of crime research. A narrow version of rational choice theory assumes actors to choose in an instrumental, outcome-oriented way. It hypothesises that individuals weight the costs and benefits of criminal acts with subjective probabilities. In contrast, a wide version of the theory allows individuals to derive utility directly from choosing certain actions. Previous studies either do not directly test these theories or yield inconsistent results. We show that a meaningful test of these rival rational choice explanations can only be conducted if a broader view is adopted that takes into account the interplay of moral norms and instrumental incentives. Such a view can be derived from the Model of Frame Selection (Kroneberg 2005) and the Situational Action Theory of Crime Causation (Wikström 2004). Based on these theories, we analyze the willingness to engage in shoplifting and tax fraud in a sample of 2,130 adults from Dresden, Germany. In line with our theoretical expectations, we find that only respondents who do not feel bound by moral norms consider instrumental incentives. Where norms have been strongly internalised and in the absence of neutralisation techniques which legitimise norm-breaking, instrumental incentives are irrelevant.
"Disney is the Tiffany’s and I am the Woolworth's of the business": A critical re-analysis of the business philosophies, production values and studio practices of animator-producer Paul Houlton Terry
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Animator-producer Paul Houlton Terry has been portrayed as having little passion for the animation he produced and being more concerned with making a profit than producing entertaining cartoons with high production values. The purpose of the dissertation is to re-evaluate Terry‘s legacy to animated cartooning by analyzing his business philosophies, production values, and studio practices.
Application of four psychodynamic factors to the early life and career of Terry, 1887-1929, found that his economic decision making was characterized by: an external locus of control, risk-averse financial behaviour, extreme saving behaviour through precaution, and shrewd money management practices. Based on Terry‘s historical responses to twelve major economic, technological, or institutional forces of change for the period 1929-1955, the psychodynamic factors were found to provide accurate explanations for his studio practices and production decisions.
There was no evidence to support the conclusion that three early career disappointments undermined Terry‘s intrinsic motivation to create animated cartoons. Rather, Terry‘s lack of risk taking, external locus of control, tight studio production schedule, desire to compete with neighbour studio Fleischer, difficulty in separating financial rewards from creative processes in animation, and practice of undertaking surveillance measures on staff may have undermined his and his studio‘s creativity. Archival research found Terry to possess strong passions for and to have made significant creative contributions to the field of animation.
Biographical research found that Terry retained a stable nucleus of highly talented artists who dedicated a significant portion of their working careers to the studio. An analysis of the cel aesthetics of a random sample of animated cartoons produced during the years 1930-1955 found that Terry created animated cartoons with above average cel aesthetics when compared to the other studios thereby supporting an inference that Terry was motivated to producing quality crafted animation. Further research is suggested into the role psychodynamic factors and economic decision-making play in the film production process and a clarification of Terry‘s legacy to the field of animated cartoons
Real Options under Choquet-Brownian Ambiguitys
Get PDFReal options models characterized by the presence of “ambiguity” (or “Knightian uncertainty”) have been recently proposed. But based on recursive multiple-priors preferences, they typically describe ambiguity through a range of Geometric Brownian motions and solve it by application of a maxmin expected utility criterion among them (worst case). This reduces acceptable individual preferences to the single case of an extreme form of pessimism. In contrast, by relying on dynamically consistent “Choquet-Brownian” motions to represent the ambiguous cash flows expected from a project, we show that a much broader spectrum of attitudes towards ambiguity may be accounted for, improving the explanatory and application potentials of these appealing expanded real options models. In the case of a perpetual real option to invest, ambiguity aversion may delay the moment of exercise of the option, while the opposite holds true for an ambiguity seeking decision maker. Furthermore, an intricate relationship between risk and ambiguity appears strikingly in our model.
