Selective feeding in response to depletion of particular reserves was examined in the American cockroach, Periplaneta americana. Animals deprived of specific nutrients and subsequently provided with dietary choices, responded so as to restore their altered reserves. Since two foods of differing energy content were used, the fundamental hypothesis of optimality theory could be tested (i.e. do cockroaches behave so as to maximize energy intake?). Adult male cockroaches were placed in a computer-monitored artificial habitat containing routes to shelter, water, protein and carbohydrate. Measures of behaviour were compared over treatments. Treatments included control cockroaches (no starvation), cockroaches fed agar (originally fed protein and sugar), protein-starved cockroaches (originally fed sugar only) and starved cockroaches (no food in the pre-treatment). In all treatments, more time was spent feeding than drinking. In controls, feeding on carbohydrate took precedence over protein (for intake and duration). Protein-starved cockroaches showed increased intake (over controls) for protein, as expected, but also increased intake for both carbohydrate and water. Starved and agar-fed cockroaches displayed decreased carbohydrate and water intake while protein consumption increased. The compensatory responses showed large initial peaks that gradually approached control behaviour. The results indicate that feeding behaviour is strongly responsive to reserve state and reserves act as an integral part of a dynamic system which operates homeostatically. The fact that depletion of the protein reserve resulted in increased ingestion of both protein and carbohydrate strongly suggests that reserves are linked. Considerable variation in daily feeding was observed which may be related to overshoot/undershoot responses typical of homeostatic systems where time lags exist. The results are strongly at variance with the predictions of optimal foraging theory. Cockroaches appear to feed to homeostatic set points, largely regulated by reserves. Reserves are largely ignored in optimal foraging theory. Furthermore, the animals regulate intake of nitrogen (protein) and/or energy, and do not simply maximize energy intake. / Thesis / Master of Science (MS)

Master of Science

This thesis examines the extent to which institutional transparency is counterproductive and potentially politicizing within the U.S. Federal Reserve system. It exemplifies a Venn diagram intersection of political and economic theory – and given the meaningful change in behavior at the Fed – to some extent organizational theory as well. This political economy orientation may be illustrated by providing a historical context – and then addressing the relevant catalysts for change: legislative action, financial crises, and the increase in social media technology. In terms of a “broader view,” these changes have occurred against a backdrop of significant changes in the application of Keynesian theories. As a result, this thesis defines modern transparency at the Federal Reserve, including its benefits and potential drawbacks, by connecting the changes in policies and procedures over the last quarter century - and by showing the impact of the evolution of modern New Keynesian interventionist programs within this new environment. The conclusions shown the New Keynesian coincidental contributions to modern interventionalist policies. But the benefits that come from improved transparency have opened the door to unintended consequences – and the main takeaway is the potential for political bias among bankers and the time inconsistencies that come from short-term modifications to otherwise long-term problems. The “secrets of the temple” are no longer secrets…but Greider would agree that the concentration of power and political influence remains the same. / M.A. / This thesis explores to what extent is increased transparency counterproductive and potentially politicizing within the U.S. Federal Reserve system. The Fed is primarily responsible for maintaining price stability, facilitating full employment, and maintaining the health of the banking system, placing it both directly and indirectly at the center of power and influence within American politics. FOMC decisions directly affect American citizens. For instance, their interest rate policies influence the cost of a mortgage, a car loan, a student loan, or possibly the value of 401k accounts – and in the 21st century, the average American is more tied to “credit” than ever before. This analysis will consider how this initiative developed, its original intent, its evolution, and why it may result in significant unintended political consequences. The conclusions illustrated that there are benefits that come from improved transparency. However, improved transparency may have opened the door to unintended consequences.

A distribution center that services value-added operations in addition to its normal operations faces a design problem: How to configure the forward/reserve departments for both of these operations. Analytical models are developed to analyze the tradeoff between floorspace and labor efficiency. Our results indicate that the best distribution center design is dependent on a company's customer demand profile as well as the relative cost of floorspace and labor. / Master of Science

O caquizeiro (Diospyros kaki L.) é uma planta caducifólia pertencente à família Ebenaceae, tendo como centro de origem a região central da China. Entre os estados brasileiros, São Paulo é o que apresenta maior produção de caquis com 49.727 t. A cercosporiose (Pseudocercospora kaki), também conhecida como mancha angular, é a principal doença foliar da cultura. Alguns autores atribuem à cercosporiose a queda precoce de folhas, maturação antecipada dos frutos e a redução da produção na safra seguinte. Entretanto, não existem trabalhos com o patossistema P. kaki - D. kaki que deem suporte a essas pressuposições. Diante disso, os objetivos desse trabalho foram comparar a susceptibilidade de quatro cultivares de caquizeiro e avaliar o efeito da cercosporiose na fisiologia da planta. Os experimentos foram conduzidos em condições naturais de campo, com as cultivares Fuyu, Rama Forte, Taubaté e Giombo, por serem as mais cultivadas no estado de São Paulo. Nos experimentos desenvolvidos buscou-se conhecer o grau de resistência das quatro cultivares à cercosporiose, avaliando a incidência, severidade e queda de folhas ao longo de dois ciclos de cultivo, assim como avaliar o controle químico na redução da doença em cvs. Taubaté e Rama Forte e, consequentemente, no acúmulo de reservas na raiz e na qualidade dos frutos colhidos. Foram avaliadas também os danos na fotossíntese em folhas das quatro cultivares com diferentes intensidades de cercosporiose. Como resultados pode-se constatar, que a cv. Fuyu é a mais susceptível à cercosporiose, seguida com resistência média \'Giombo\' e \'Rama Forte\' e com maior resistência a cv. Taubaté. A intensidade da cercosporiose, para severidades da doença de até 7% não influencia na queda de folhas. O controle químico reduziu a intensidade de doença nas cvs. Taubaté e Rama Forte, entretanto, entre as intensidades de cercosporiose avaliadas em plantas tratadas e não tratadas, não há redução no acúmulo de reservas no sistema radicular, assim como na qualidade físico-química dos frutos colhidos. Mesmo a cercosporiose afetando a fotossíntese, no processo fotoquímico, tanto na área lesionada como na área adjacente à lesão, a intensidade da doença observada no campo não foi suficiente para causar redução da produção à cultura. / The persimmon (Diospyros kaki L.) is a deciduous plant of the botanical family Ebenaceae, native to central China. Among the Brazilian states, São Paulo has the highest production of persimmon with 49,727 ton/year. The angular leaf spot of persimmon (Pseudocercospora kaki), also known as cercosporiosis, is the main leaf disease of the crop. Some authors attribute to the cercosporiosis the premature defoliation, early maturation of the fruits and the reduction of the yield in the next crop cycle. However, there are no previous studies with the Pseudocercospora kaki pathosystem that support these hypotheses. Therefore, the objectives of this study were to compare the susceptibility of four persimmon cultivars and evaluate the effect of angular leaf spot on plant physiology. A field experiment was conducted with Fuyu, Rama Forte, Taubaté and Giombo cultivars, the four most cultivated in the state of São Paulo. The degree of resistance to cercosporiosis was determined by the incidence and severity of the disease and by defoliation of the plants in two crop cycles. Chemical spraying for the disease reduction was also evaluated in cvs. Taubaté and Rama Forte. The reduction of the carbohydrate reserve accumulation in the roots and the quality of the fruits harvested were tested. The photosynthesis reduction was also evaluated in leaves of the four cultivars with different intensities of cercosporiosis. The Fuyu cultivar was the most susceptible to cercosporiosis, followed by moderate resistance of \'Giombo\' and \'Rama Forte\' and high resistance of cv. Taubaté. The intensity of cercosporiosis, for disease severity up to 7% does not influence leaf drop. Though the chemical control reduced the disease intensity in cvs. Taubaté and Rama Forte, treated and untreated plants showed no differences in the reserves accumulation in the roots, as well as in the physicochemical quality of the harvested fruits. Even though cercosporiosis affects photosynthesis in the photochemical process on both the necrotic and remaining green leaf area, the intensity of the disease observed in the field was not enough to cause yield reduction to the culture.

This study assessed change in the dietary intake and weight, height and body mass index (BMI. kg/ml) measurements of children (grades 4--6) who have participated in the Kahnawake Schools Diabetes Prevention Program (KSDPP). Children from two independent cross sectional samples were assessed at baseline in 1994 (n = 156) and in 1998 (n = 146). Diet was assessed using a single 24-hour recall. Results showed no overall change in energy, fat and sucrose intake. Food groups were created as indicators of diet quality. Results showed a decrease in the frequency of consumption of foods in the high fat food group (p < 0.05) and an increase in the average amount of white sugar consumed (p < 0.05). A decrease in the number of servings of fruit was shown, but also a trend towards their increased frequency of consumption. No significant changes were found in weight, height or BMI. Dietary and anthropometric data were combined but results showed no significant changes in diet by BMI category. Changes in diet are challenging to both measure and implement. These results could be used to identify more specific future interventions.

With the purpose of improving the conservation management of Ithala Game Reserve and other similar reserves, the aims of this study were to determine the reserve's large mammalian herbivores' habitat occupancy, numbers and demographics, to investigate the feasibility of road strip counts as a census method for the same herbivores and to establish what environmental factors influence their habitat occupancy, numbers and demographics. Four years of demographic data were collected by vehicle transects on giraffe, kudu, wildebeest and impala. During the final two years additional positional data, using GPS, were collected on these and the reserve's other large herbivores. Sightings were recorded on the basis of habitat type occupied, a GIS was then used to define area sampled and hence derive habitat occupancy densities. GIS was further used to determine both absolute population sizes and, by over-laying other available GIS data, the relevance of distance to surface water, soil type and degree of slope to species' habitat preferences. Species showed non-random, significant habitat selections broadly in line with established preferences. Deterioration in habitat quality in winter generally lead to changes in habitat selection and the extent and nature of these changes related to the severity of resource pressure for individual species. This in turn was influenced by the species digestive strategy i.e. ruminant versus non-ruminant, grazer versus browser. Generally species showed a dry season move down the slope, moving, in some cases, onto heavier soils. Hartebeest, warthog, wildebeest and impala were strongly attracted to winter grass flushes. Lack of predation may be influencing the habitat selection decisions of impala and giraffe and kudu females, as well as allowing giraffe, wildebeest and impala to attain comparatively high densities. Giraffe density (effectively 1.8 km - 2) was abnormally high and their habitat quality poor, leading to a decline in numbers and low fecundity-related demographics. Wildebeest density (6 km -2) was also abnormally high and this may be instrumental in the poor performance of the rare tsessebe population, which is in decline and shows low fecundity-related demo graphics, increased dry season pressure on other grazers in general and impala 111 unexpectedly preferring browse habitats, rather than grasslands, in the wet season. Wildebeest fecundity declined in response to lower rainfall over the early period of lactation. Herbivores with an open social structure generally showed a dry season decrease in group size, although wildebeest and hartebeest showed, atypically, an Increase. Giraffe, zebra and impala adult sex ratios were comparatively less female biased, probably due to minimal predation. Territorial behaviour, virtually year round by wildebeest bulls and over the rut by impala bulls, imposed spatial sexual segregation between breeding and bachelor herds in these species. Outside of these periods, and generally in species not exhibiting territoriality, social sexual segregation was maintained and appeared to relate to differing activity budgets. Areas of concern for management are highlighted. Numbers results were generally acceptable and the method is proposed as a cost effective alternative in reserves with diverse topography. Underlying environmental determinants of habitat occupancy, numbers and demographics, together with associated annual or seasonal changes, were habitat quality, competition and predation. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2005.

Two management blocks were set aside in Umfolozi Game Reserve (UGR) to compare different management approaches. In one, the non-cull block, a noninterventionist policy was followed and no large mammals were removed, while the other, the cull block was subjected to the same game removal treatment as the remainder of the reserve. The main objectives of this study were to determine the relationships between vegetation, soil surface variables and both soil loss and rainfall run-off, to derive predictive models for run-off and soil loss based on vegetation and soil surface variables, to determine the relationship between different levels of soil erosion and the production potential of soils, and to determine the relationship between different levels of soil erosion and herbaceous species diversity. Rainfall simulator trials and natural run-off plots were used to collect quantitative data on soil loss and run-off. Bivariate scattergrams showed that the relationship between soil surface and vegetation variables plotted against soil loss was curvilinear. "Susceptibility to erosion" showed the highest positive correlation, and "surface cover" the highest negative correlation with soil loss. The relationship between annual run-off and both the soil surface and vegetation variables was also curvilinear, with "soil capping" showing the highest positive and "litter cover" the highest negative correlation with run-off. Using multiple regression analysis it was found that "susceptibility to erosion" and predictors of annual soil loss. "surface cover" were the best "Soil capping" and "percentage contribution of run-off. forbs" were the best predictors of annual No clear relationship between either soil loss and stocking rate, or run-off and stocking rate was apparent in the two experimental blocks, and the differences in soil loss and run-off could not be explained by differences in stocking rate alone. There were however defects in the experimental design which invalidated the assumption that the stocking ~ate diffe~entia1 management blocks would inc~ease with time. between the two Because of the above deficiency, an a1te~native study a~ea on the weste~n bounda~y fence, which allowed fo~ pai~ed sampling sites on eithe~ side of the fence, was chosen. Ge~lach t~oughs we~e used to measu~e soil loss. The g~eatest va~iabi1ity in soil loss was explained by the position of the plots on the slope ~athe~ than whethe~ the plots we~e in UGR o~ in adjacent KwaZu1u. Simi1a~ly, diffe~ences in topog~aphy, ~athe~ than diffe~ences in 1anduse, exe~ted an ove~~iding effect on A-ho~izon depth, he~bage accumulation and g~ass species ~ichness. Conside~ing the ~esu1ts obtained, the opinion that a noninte~ventionist policy would lead to a decline in vegetation p~oductivity and to a 10ng-te~m ~eduction in species dive~sity appea~s to be unfounded. Finally, based on the data collected and on a ~eview of cu~~ent scientific 1ite~atu~e, changes to the Natal Pa~ks Boa~d soils policy and objectives a~e suggested, and the objectives a~e t~ans1ated into ope~ationa1 management goals. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1988.

Thesis (Ph. D.)--University of Hong Kong, 1995. / Photocopy of the original. Includes bibliographical references (leaf 130-157).

Thesis (Ph. D.)--University of Hong Kong, 1993.