Briery Creek Lake (BCL) has low abundance of young largemouth bass (LMB) compared to Sandy River Reservoir (SRR), which could jeopardize the trophy-LMB management goal in BCL. I assessed factors that may limit recruitment of LMB in BCL: angling, predation, competition, growth, and food availability. Age-0 LMB were monitored from nesting through their first summer with nest surveys, light traps, and electrofishing. Nesting success was higher in BCL (53%) than SRR (31%). Initial light trap catch-per-unit-effort (CPUE) was higher in BCL than SRR but, by July, light trap and electrofishing CPUE was higher in SRR than BCL. LMB nest success, growth, and CPUE did not differ between areas in BCL that were experimentally closed and areas left open to angling. Predation on age-0 LMB did occur in BCL, but was not higher than predation in SRR. Diet overlap between age-0 LMB and bluegill in BCL was >60% during June, indicating potential for competition. Zooplankton samples indicated that density of copepods was similar between reservoirs (2.3/liter); however, the average size of copepods was smaller in BCL (0.42 mm) than SRR (0.71 mm). I examined the activity of trypsin, which digests and converts protein. Trypsin activity was lower in BCL than SRR on 23 and 27 June, indicating that a nutritional deficiency exists for age-0 LMB in BCL. This deficiency was likely caused by the reduced zooplankton size in BCL and led to slower growth of age-0 LMB during June in BCL (0.8 mm/day) than SRR (1.2 mm/day). The fact that age-0 LMB CPUE in BCL dropped lower than SRR by July, despite BCL having a greater nesting success and higher CPUE in early June, indicates that a recruitment bottleneck for LMB occurred in June. Maintaining the trophy LMB fishery in BCL requires management options that consider the factors in June that affect recruitment. I recommend decreasing the presently overabundant aquatic macrophytes in BCL, thus allowing for increased nutrient availability for phytoplankton, the primary food source of zooplankton. This could increase the density and size structure of zooplankton, and thereby increase food availability for age-0 LMB. / Ph. D.

Same types of systems with the same age usually have different amounts of cumulated usage. These systems when in operation usually have different performance and effectiveness. In this case the existing models of the univariate measures of system effectiveness are inadequate and incomplete. For example, the univariate availability measures for these same-aged systems are all the same even though with different amounts of usage. This is the motivation for this research to pursue a bivariate approach in reliability and maintenance modeling. This research presents a framework for bivariate modeling of a single-unit system. Five key efforts are identified and organized as: (i) bivariate failure modeling, (ii) bivariate renewal modeling, (iii) bivariate corrective maintenance (CM) modeling, (iv) bivariate preventive maintenance (PM) modeling, and (v) bivariate availability modeling. The results provide a foundation for further study of bivariate and multivariate models. For bivariate failure modeling, several bivariate failure models are constructed to represent the possible correlation structures of the two system aging variables, time and usage. The behavior of these models is examined under various correlation structures. The developed models are used to analyze example maintenance problems. Models for bivariate renewal, bivariate CM, and bivariate PM are derived based on the constructed bivariate failure models and the developed bivariate renewal theory. For bivariate CM modeling, corrective maintenance is modeled as an alternating bivariate renewal process or simply an ordinary bivariate renewal process. For bivariate PM modeling, PM models are examined under a bivariate age replacement preventive maintenance policy. The Laplace transforms of the renewal functions (and densities) for these models are obtained. Definitions for bivariate availability functions are developed. Based on the derived CM and PM models, the Laplace transforms for their corresponding bivariate availability models are constructed. The idea of the quality of availability measure is also defined in terms of bivariate availability models. The most significant observation is that this framework provides a new way to study the reliability and maintenance of equipment for which univariate measures are incomplete. Therefore, a new area of reliability research is identified. The definitions offered may be modified and the approach to model formulation presented may be used to define other models. / Ph. D.

Background: Achilles tendinopathy is a common and debilitating condition among female ballet dancers due to the large repetitive loading forces placed on their Achilles tendons during rehearsals and performances. Tendon health problems in females are exacerbated by a lack of understanding about how energy availability influences tendons. Ballet dancers, as aesthetic athletes, are vulnerable to low energy availability and can enter a spectrum disorder, relative energy deficiency in sport, that consists of low energy availability (with or without disordered eating), menstrual cycle dysfunction, and low bone mineral density (BMD). Aims: 1) To investigate the relationship between insufficient caloric intake and Achilles tendon health in pre-professional ballet dancers. 2) To evaluate if symptoms of relative energy deficiency in sport such as low BMD and menstrual irregularity can be matched with Achilles tendon structural damage in pre-professional ballet dancers. 3) To analyze if there is a relationship between BMD and nutrition in pre-professional ballet dancers. Methods: 30 pre-professional ballet dancers were recruited. Over the course of a 16-week training and performance period, the dancers underwent four ultrasound imaging sessions and two MRI sessions investigating their Achilles tendons. They also underwent one full body DXA scan and completed four ASA24 dietary recall surveys. The dancers additionally filled out questionnaires describing their menstrual history and current Achilles tendon health. At the end of the study, dancers were organized into calorie sufficiency groups (sufficient or insufficient). Results: Within both calorie groups, the Achilles tendon was significantly thicker at the end of the study as compared to the start of the study (p=.046). Within both calorie groups, echogenicity was significantly higher at the first two ultrasound imaging sessions than it was at the last two (p<.05). Additionally, the calorie sufficient group's tendons had a significantly higher echogenicity than the calorie insufficient group at the first two ultrasound imaging sessions (p<.05). There were significantly more dancers in the calorie insufficient group that experienced changes to their menstrual cycle (p=.007). Conclusion: Participants in the calorie sufficient group had significantly more hyperechoic tendons than those in the calorie insufficient group at the start of the study, and all participants saw a significant drop in tendon echogenicity halfway through the study. The results of this study suggest that a better understanding of how average caloric intake affects tendon health in dancers is necessary in order to help treat and prevent AT injuries in this dance population.

The use of availability measures is very informative when analyzing the performance of repairable components. The derivation and evaluation of such measures is usually focused on describing the status of the component over time. It is not generally acknowledged that the resulting availability measure is in fact an expected value with respect to frequency. In a population of n independent, identical components, the number functioning at any point in time is a random variable. The distribution of this random variable is determined and described here. The intuitive view that this frequency distribution is binomial is verified. This is accomplished using direct analysis and Monte Carlo simulation. Two general cases are considered: (1) components with exponential life and repair time distributions, and (2) components with Weibull life distributions and exponential repair time distributions. The analysis leads to more accurate models of component behavior in terms of frequency including an exact confidence bound on the number of components functioning at any point in time. In addition, the time evolution of the frequency distribution is described and the relationships between the frequency distribution and the life and repair time distribution parameters are explored. Finally, the implications for availability decision analyses are shown. The overall result is a new perspective on availability which should prove to be very useful. / Master of Science

In an era of global-scale climate change, agricultural production faces a unique challenge due to its reliance on stochastic natural endowments, including temperature, precipitation, and water availability for irrigation. This dissertation presents a series of essays to examine how agricultural producers react and adapt to challenges presented by climate change and scarce irrigation water allocated through the prior appropriation doctrine. The dissertation approaches the problem from three distinct perspectives: institutional differences, climate and water availability, as well as producers' expectation on future endowments. Chapter 2 presents an institutional perspective, in which I investigate how different water allocation mechanisms within the prior appropriation doctrine result in differences in producers' crop allocation decisions. I find that water users in irrigation districts are able to plant more water-intensive crops than farmers outside irrigation districts. Chapter 3 presents the interaction between nature and human systems, in which I examine how the physiological complementarity of temperature and water availability diffuses from crop yield (at the intensive margin) to crop allocation strategies (at the extensive margin). Using a theoretical model I show that the observed complementarity reflects a combination of two mechanisms: yield impact through physiological complementarity, and adaptation response through shifting crop allocation patterns. Using an empirical model, I find that farmers adapt to changing climate conditions by growing more profitable crop mixes when presented with more growing degree-days (GDD), precipitation and groundwater access. Chapter 4 presents a behavioral perspective, in which I test how producers' expectation formation processes lead to short term over-adjustments to weather and water availability fluctuations. Using a fixed-effect regression on lagged weather and water realizations, I find that agricultural producers engage in a combination of cognitive biases, including the availability heuristic and the reinforcement strategy. Adopting these alternative learning mechanisms causes farmers to significantly over-react to more recent fluctuations in weather and water availability when making ex ante acreage and crop allocation decisions. / Ph. D. / In an era of global-scale climate change, agricultural production faces a unique challenge due to its reliance on variable natural factors, including temperature, precipitation, and water availability for irrigation. This dissertation presents a series of essays to examine how agricultural producers react and adapt to challenges presented by climate change and scarce irrigation water allocated through the prior appropriation doctrine. Chapter 2 presents an institutional perspective, in which I investigate how different water allocation regimes result in differences in producers’ cropping decisions. I find that irrigation districts benefit its users by allowing them to plant more water-intensive crops than farmers outside irrigation districts. Chapter 3 presents a natural science perspective, in which I examine how temperature and water availability jointly affect agricultural production and adaptation. I find that farmers significantly adapt to changing climate conditions by growing more profitable crop mixes when presented with higher temperature, precipitation, and groundwater access. Chapter 4 presents a behavioral perspective, in which I test how agricultural decision making are affected by how producers form expectations over future climate. I find that agricultural producers engage in a combination of cognitive biases when forming expectations, and as a result over-react to more recent fluctuations in weather and water availability when making acreage and crop allocation decisions.

The number of overweight adults has risen to two-thirds of the population, thus increases in energy intake, particularly from beverages are of great concern. Sugar-sweetened beverage (SSB) intake has increased by 222 calories in recent decades, which contributes a significant source of added sugars to the American diet. It has been reported that water consumers have a lower overall energy intake (~194 kcals) as compared to non-consumers of water therefore substituting water for SSBs may facilitate weight loss and weight management. Evidence also indicates that diet quality follows a socioeconomic gradient, and that the environment has a powerful influence on beverage consumption. Thus, modifying the food environment could be a promising strategy for promoting healthier beverage consumption behavior. A large portion of the US population spends their day at a worksite making the worksite a viable setting for implementing environmental approaches to promote effective behavior change. At this time, it is unclear if a reduction of SSB intake would be a viable dietary weight management intervention strategy. Therefore, our purpose was to determine if water, SSB intake, SSB energy, total beverage intake, and total beverage energy varies with individual and environmental factors among overweight and obese employees from 28 worksites involved in a randomized controlled weight management trial. These findings may contribute to the development of tailored weight management programs aimed to improve beverage consumption patterns. / Master of Science

Yes / Our global age is practically defined by the ubiquity of the Internet; the worldwide interconnection of cyber networks that facilitates accessibility to virtually all ICT and other elements of critical infrastructural facilities, with a click of a button. This is regardless of the user’s location and state of equilibrium; whether static or mobile. However, such interconnectivity is not without security consequences. A telecommunication system is indeed a communication system with the distinguishing key word, the Greek tele-, which means "at a distance," to imply that the source and sink of the system are at some distance apart. Its purpose is to transfer information from some source to a distant user; the key concepts being information, transmission and distance. These would require a means, each, to send, convey and receive the information with safety and some degree of fidelity that is acceptable to both the source and the sink. Chapter K begins with an effort to conceptualise the telecommunication network security environment, using relevant ITU-T2* recommendations and terminologies for secure telecommunications. The chapter is primarily concerned with the security aspect of computer-mediated telecommunications. Telecommunications should not be seen as an isolated phenomenon; it is a critical resource for the functioning of cross-industrial businesses in connection with IT. Hence, just as information, data or a computer/local computer-based network must have appropriate level of security, so also a telecommunication network must have equivalent security measures; these may often be the same as or similar to those for other ICT resources, e.g., password management. In view of the forgoing, the chapter provides a brief coverage of the subject matter by first assessing the context of security and the threat-scape. This is followed by an assessment of telecommunication network security requirements; identification of threats to the systems, the conceivable counter or mitigating measures and their implementation techniques. These bring into focus various cryptographic/crypt analytical concepts, vis a vis social engineering/socio-crypt analytical techniques and password management. The chapter noted that the human factor is the most critical factor in the security system for at least three possible reasons; it is the weakest link, the only factor that exercises initiatives, as well as the factor that transcends all the other elements of the entire system. This underscores the significance of social 2*International Telecommunications Union - Telecommunication Standardisation Sector 12 engineering in every facet of security arrangement. It is also noted that password security could be enhanced, if a balance is struck between having enough rules to maintain good security and not having too many rules that would compel users to take evasive actions which would, in turn, compromise security. The chapter is of the view that network security is inversely proportional to its complexity. In addition to the traditional authentication techniques, the chapter gives a reasonable attention to locationbased authentication. The chapter concludes that security solutions have a technological component, but security is fundamentally a people problem. This is because a security system is only as strong as its weakest link, while the weakest link of any security system is the human infrastructure. A projection for the future of telecommunication network security postulates that, network security would continue to get worse unless there is a change in the prevailing practice of externality or vicarious liability in the computer/security industry; where consumers of security products, as opposed to producers, bear the cost of security ineffectiveness. It is suggested that all transmission devices be made GPS-compliant, with inherent capabilities for location-based mutual authentication. This could enhance the future of telecommunication security. / Petroleum Technology Development Fund

No description available.

O ácido elágico é um composto fenólico responsável por diversas atividades biológicas tais como antioxidante e/ou anticarcinogênica e está presente algumas frutas e nas nozes. As bagas, mais conhecidas como berries e a romã são as fontes mais conhecidas de ácido elágico, porém, não são alimentos usualmente consumidos na dieta brasileira. Desta forma, o objetivo deste trabalho foi realizar um screening em frutas e sementes em relação aos seus teores de ácido elágico e a partir do screening, selecionar uma fruta para estudo dos teores de ácido elágico durante sua maturação. Um total de 35 variedades de frutas (21 famílias botânicas) e 11 tipos de sementes (9 famílias botânicas) foram avaliadas por CLAE quanto ao teor de ácido elágico livre e total. O ácido elágico total foi quantificado após hidrólise dos elagitaninos utilizando TFA 2N a 120&#186;C por 90 minutos. O ácido elágico foi encontrado em 10 das 35 variedades de frutas e em 3 das 11 variedades de sementes avaliadas. Em frutas, seus teores variaram entre 0,28 e 8,5 mg/100 g b.u. de ácido elágico livre e entre 21,5 e 311 mg/100 g b.u. de ácido elágico total, sendo a jabuticaba, a grumixama e o cambuci (família Myrtaceae) as frutas que apresentaram os maiores teores. Entre as sementes, 3 amostras apresentaram entre 0,37 e 41 mg/100 g e entre 149 e 823 mg/100 g respectivamente de ácido elágico livre e total, sendo as nozes e a pecan (família Juglandaceae), as principais fontes. Em frutas que apresentaram ácido elágico, realizou-se ainda uma caracterização quanto aos teores de fenólicos totais, vitamina C e capacidade antioxidante. A partir destes resultados, a jabuticaba foi a fruta selecionada para estudo dos teores de ácido elágico em função dos estágios de maturação, onde se observou em todas as porções casca, polpa e semente, decréscimo nos seus teores com a maturação. / Ellagic acid is a phenolic compound present in fruis and nuts which acts as potent anti-oxidant and anti-carcinogenic. Berries and pomegranate are the main sources of ellagic acid, however, these fruits are not commonly consummed in the Brazilian diet. Thus, the objective of this work was screened fruits and nuts for content of ellagic acid and according to this, one fruit was selected for studing the ellagic acid content during maturation. Thirty five varieties of fruits (21 bothanical families) and eleven nut samples (9 bothanical families) were evaluated for content of ellagic acid by HPLC. Total ellagic acid content was quantified after ellagitannins hydrolysis using 2N TFA 120&#186;C for 90 min. Ellagic acid was detected in 10 of 35 fruits and in 3 of 11 nuts. The content of free ellagic acid in fruits varied from 0.28 to 8.5 mg/100 g (FW) and the total ellagic acid varied from 21.5 to 311 mg/100g (FW), whereas jabuticaba, grumixama and cambuci (Myrtaceae family) showed higher ellagic acid content. Among nuts, three samples showed free and total ellagic acid content ranging from 0.37 to 41 and from 149 to 823 mg/100 g (FW) respectively. Among them, walnut and pecan (Juglandaceae family) were the main sources. Total phenolic content, antioxidant capacity and ascorbic acid content were also evaluated in fruits which contained ellagic acid. According these results, jabuticaba was selected for determine the content of ellagic acid during maturation and it was observed decreasing in all parts - skin, pulp and seed - during maturation.

O ácido elágico é um composto fenólico responsável por diversas atividades biológicas tais como antioxidante e/ou anticarcinogênica e está presente algumas frutas e nas nozes. As bagas, mais conhecidas como berries e a romã são as fontes mais conhecidas de ácido elágico, porém, não são alimentos usualmente consumidos na dieta brasileira. Desta forma, o objetivo deste trabalho foi realizar um screening em frutas e sementes em relação aos seus teores de ácido elágico e a partir do screening, selecionar uma fruta para estudo dos teores de ácido elágico durante sua maturação. Um total de 35 variedades de frutas (21 famílias botânicas) e 11 tipos de sementes (9 famílias botânicas) foram avaliadas por CLAE quanto ao teor de ácido elágico livre e total. O ácido elágico total foi quantificado após hidrólise dos elagitaninos utilizando TFA 2N a 120&#186;C por 90 minutos. O ácido elágico foi encontrado em 10 das 35 variedades de frutas e em 3 das 11 variedades de sementes avaliadas. Em frutas, seus teores variaram entre 0,28 e 8,5 mg/100 g b.u. de ácido elágico livre e entre 21,5 e 311 mg/100 g b.u. de ácido elágico total, sendo a jabuticaba, a grumixama e o cambuci (família Myrtaceae) as frutas que apresentaram os maiores teores. Entre as sementes, 3 amostras apresentaram entre 0,37 e 41 mg/100 g e entre 149 e 823 mg/100 g respectivamente de ácido elágico livre e total, sendo as nozes e a pecan (família Juglandaceae), as principais fontes. Em frutas que apresentaram ácido elágico, realizou-se ainda uma caracterização quanto aos teores de fenólicos totais, vitamina C e capacidade antioxidante. A partir destes resultados, a jabuticaba foi a fruta selecionada para estudo dos teores de ácido elágico em função dos estágios de maturação, onde se observou em todas as porções casca, polpa e semente, decréscimo nos seus teores com a maturação. / Ellagic acid is a phenolic compound present in fruis and nuts which acts as potent anti-oxidant and anti-carcinogenic. Berries and pomegranate are the main sources of ellagic acid, however, these fruits are not commonly consummed in the Brazilian diet. Thus, the objective of this work was screened fruits and nuts for content of ellagic acid and according to this, one fruit was selected for studing the ellagic acid content during maturation. Thirty five varieties of fruits (21 bothanical families) and eleven nut samples (9 bothanical families) were evaluated for content of ellagic acid by HPLC. Total ellagic acid content was quantified after ellagitannins hydrolysis using 2N TFA 120&#186;C for 90 min. Ellagic acid was detected in 10 of 35 fruits and in 3 of 11 nuts. The content of free ellagic acid in fruits varied from 0.28 to 8.5 mg/100 g (FW) and the total ellagic acid varied from 21.5 to 311 mg/100g (FW), whereas jabuticaba, grumixama and cambuci (Myrtaceae family) showed higher ellagic acid content. Among nuts, three samples showed free and total ellagic acid content ranging from 0.37 to 41 and from 149 to 823 mg/100 g (FW) respectively. Among them, walnut and pecan (Juglandaceae family) were the main sources. Total phenolic content, antioxidant capacity and ascorbic acid content were also evaluated in fruits which contained ellagic acid. According these results, jabuticaba was selected for determine the content of ellagic acid during maturation and it was observed decreasing in all parts - skin, pulp and seed - during maturation.