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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Diverzita a taxonomie zástupců rodu Geastrum ve Střední Americe / Diversity and taxonomy of members of genus Geastrum in Central America

Zehnálek, Petr January 2017 (has links)
In temperate zone, especially Europe and North America, is the genus Geastrum very well inspected group of Gasteromycetes with long lasting and comprehensive history of research. Our knowledge of the diversity in other areas of distribution, especially in tropics, is more than limited. The aim of this diploma thesis is to contribute for cognition of diversity of this genus in Panama, Costa Rica and Colombia I have collected 86 samples belonging to genus Geastrum during three expeditions to Panama (Chiriqué province) in the years 2015, 2016, 2017. I have characterized those based on morphological and molecular data. I have also studied morphology of 40 borrowed herbarium specimens from Costa Rica, Colombia and Panama. I have successfully sequenced four locuses of DNA from my own samples (ITS, LSU, RPB1 and ATP6). This method had lover efficiency in herbarium specimens due to present contaminations, age of specimens or probably badly stored. Molecular phylogenetic analysis was carried out by Bayesian method and its results have in agreement with morphologic traits shown many lineages new for Panama and moreover at least four new species completely new to science. Variability in species complexes (e.g. G. lageniforme, G. saccatum, G. velutinum) is presented in more detail with emphasis to lineages...
172

Panamanian Politics and Panama’s Relationship with the United States Leading up To the Hull-Alfaro Treaty

Hamilton, Sheila 27 August 2014 (has links)
This thesis explains the origins of the 1936 Hull-Alfaro Treaty between Panama and the United States. It examines how Panamanian politics and Panama’s relationship with the United States changed over the decades leading up to this new treaty. The Panama Railway and then the Panama Canal placed Panama in a unique position within the growing American Empire as the isthmus linked the United States to the resources it needed to fuel its domestic industry and to markets for its manufactured goods. Recurrent political unrest and economic challenges within Panama forced the Panamanian government to attempt to renegotiate its relationship with the United States. This work analyzes the changes within Panamanian society, United States foreign relations, and world affairs that led to the 1936 treaty succeeding where other treaty negotiations had not. / Graduate / 0336 / skookum_1998@hotmail.com
173

Neogene Changes in Caribbean Paleoproductivity and the Diversity and Paleobiogeography of Deep-sea Benthic Foraminifera

Pletka, Crystal 28 March 2016 (has links)
The Neogene history of Caribbean deep-sea benthic foraminifera was investigated by calculating changes in paleoproductivity, diversity and paleobiogeography ~26 to 2 Ma, which includes the progressive closure of the Central American Seaway. Three hypotheses were tested: (1) Paleoproductivity values prior to closure of the Central American Seaway are similar in both the Caribbean and equatorial Pacific and then diverge by the time of early shoaling events; (2) Diversity values of benthic foraminifera prior to the closure of the Central American Seaway were similar in the Caribbean and EEP, and had changed by the time of early shoaling; and (3) during the Miocene and into the Pleistocene, the progressive constriction of the CAS affected deep-sea benthic foraminiferal assemblages by increasing their dissimilarity between the Caribbean and equatorial Eastern Pacific. These hypotheses were tested with 104 samples from five Caribbean and EEP deep-sea cores by calculating paleoproductivity with multiple proxies, determining diversity indices and calculating biogeographic similarity coefficients. The data supported the first two hypotheses: The greatest change in paleoproductivity occurred at ~8 Ma during seaway constriction, when values diverged between the Caribbean and EEP. After complete seaway closure at ~4 Ma, the Caribbean became oligotrophic, noted by a decrease in high-organic flux species, and an increase in Nuttalides umbonifera, an indicator species. The largest changes in species-level diversity occurred with the barrier to deep-water flow at ~12 Ma, and Caribbean diversity increased at ~8 Ma with seaway constriction. However, the third hypothesis was rejected: Increases in assemblage similarity actually occurred during most major paleoceanographic events, with the only decrease in Caribbean-EEP similarity occurring at ~12 Ma, coincident with a drop in diversity and emplacement of the Panama isthmian sill. Thus, the barrier to deep-water flow at ~12 Ma affected the composition of tropical American benthic foraminifera more than the largest change in paleoproductivity at ~8 Ma, or closure of the Central American Seaway at ~4 Ma.
174

Postavení vybraných středoamerických států ve světové ekonomice / The Position of Selected Central American Countries in the World Economy

Kocián, Jakub January 2014 (has links)
The aim of this diploma thesis is to analyse position of selected Central American countries in the world economy. Selected countries are Nicaragua, Costa Rica and Panama. The thesis is divided into five main chapters. The first chapter provides general information about Central America. The second, third a fourth chapter characterize general and economic information, international trade, foreign direct investments and future possibilities and perspectives of selected countries. In the last part I describe socioeconomic comparison of selected countries.
175

Biological control of Fusarium oxysporum f.sp. cubense using non-pathogenic F. oxysporum endophytes

Belgrove, Aneen 26 June 2008 (has links)
Fusarium oxysporum f.sp. cubense Schlecht (Foc), causal agent of Fusarium wilt of banana (Panama disease), is considered to be one of the most serious threats to banana production in the world. There is no effective control measure for Fusarium wilt, except for the replacement of susceptible with resistant banana varieties. However, resistant varieties are not always acceptable to producers and local consumer markets. A greater awareness of the detrimental effect of chemicals on the environment has stimulated research on biological control of plant pathogens. The use of indigenous microorganims, such as non-pathogenic F. oxysporum and the bacterium Pseudomonas fluorescens, therefore, offers not only an environmentally safe but also an economical approach to combat Fusarium wilt of banana as part of an integrated disease management strategy. Non-pathogenic F. oxysporum and P. fluorescens isolates have previously been isolated from the root rhizosphere in disease suppressive soils. These isolates have the ability to reduce the incidence of Fusarium wilt in greenhouse pathogenicity trials. In this study we had hoped to expand on existing knowledge on the biological control of Fusarium wilt of banana with non-pathogenic endophytic F. oxysporum and P. fluorescens. Isolates that significantly suppress disease development in greenhouse trials were tested under field conditions. Physiological and histological studies were also performed to understand the modes of action of putative biological control agents. For the histological investigations, non-pathogenic F. oxysporum isolates were modified with green and red fluorescent proteins. Chapter 1 depicts a general overview of the biological control of Fusarium wilt diseases of agricultural crops. This chapter addresses the biology and pathogenesis of F. oxysporum, before strategies to control Fusarium wilt are discussed. The application of biological control organisms was analysed in terms of potentially useful organisms, where they can be isolated, and their possible modes of action. Finally, factors that influence biological control of Fusarium wilt diseases are discussed. A good source of prospective biocontrol agents is suppressive soils. In Chapter 2, non-pathogenic F. oxysporum isolates were collected from healthy banana roots in disease suppressive soil. Random Fragment Length Polymorphisms of the intergenic spacer region were then applied to group the non-pathogenic F. oxysporum isolates into genotypes, from which candidates were selected for biological control studies. The selected endophytes were then inoculated onto banana roots to determine their ability to act as biocontrol agents against Foc. The isolates that protected banana best against Fusarium wilt in the greenhouse, together with P. fluorescens WCS 417, were tested in the field to determine whether these isolates could effectively reduce disease incidence in an uncontrolled environment. The ability of non-pathogenic F. oxysporum and P. fluorescens WCS 417 to induce systemic resistance in Cavendish banana plants against Foc was investigated in Chapter 3 with the use of a split-root technique. The putative biocontrol agents were inoculated, separately and in combination, on one half of the roots in a split-root experiment, while the other half was challenged by a pathogenic isolate of Foc. Five different phenolic acids were assayed which included total soluble phenolic acids, non-conjugated (free acids) phenolic acids, ester-bound phenolic acids, glycosidebound phenolic acids and cell wall-bound phenolic acids. The knowledge gained will contribute to the understanding of how the biocontrol agents may induce defense responses in banana roots against Foc. Non-pathogenic isolates of F. oxysporum were transformed with the green fluorescent protein (GFP) and DsRed-Express genes in Chapter 4. These isolates were used to visualise their interactions with a GFP-transformed Foc isolate on the banana root in a non-destructive manner by means of confocal laser scanning microscopy (CLSM) in Chapter 5. The ability of non-pathogenic F. oxysporum and P. fluorescens WCS 417 to induce structural changes was also investigated with a split-root system using the CLSM. Antibioses as a mode of action of the two potential biocontrol agents was tested in vitro. Understanding the modes of action of non-pathogenic F. oxysporum and P. fluorescens WCS 417 are important when considering strategies for the implementation of these isolates in an integrated disease management strategy against Fusarium wilt of banana. / Dissertation (MSc (Plant Pathology))--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted
176

Development and Application of Decision-Making Tool for Rural Spring-Sourced Gravity-Fed Community Managed Water Systems

Galicia, Oswaldo 14 March 2019 (has links)
People all over the world still lack access to safe drinking water service. Those with access experience several issues during the first few years of installation that impede on their overall access. In order to improve water services, not only is a proper decision-making tool necessary, taking into account key factors that impact sustainable water service, but proper monitoring and evaluation is also important in ensuring service for the long term. There are several developed assessment tools used for monitoring and evaluation of water systems post-construction, applicable in various scenarios. However, there are only few tools available to facilitate the decision-making process for stakeholders implementing water systems in the field. Ideally, one tool could be used across various life-cycle stages, like planning (decision-making) and post-construction (monitoring and evaluation). Currently, several stakeholder groups are working in Panama to improve the access of safe drinking water for rural and indigenous populations living in mountainous areas, where spring-sourced gravity-fed community-managed systems are common. Effective sustainability assessment tools including Rural Water and Sanitation Information System, SIASAR in Spanish, provide useful frameworks to create a decision making tool for this development context. This research focused on developing a Decision-Making Tool using three key assessment tools (SIASAR, Peace Corps Panama WASH Index, & Schweitzer’s Sustainability Assessment Tool), field experience, and relevant literature incorporating technical, social, economic, and environmental factors. The Decision-Making Tool was developed to build or rehabilitate a rural spring-sourced gravity-fed community-managed water system and also serve as a practical monitoring and evaluation tool. The tool has a total of 10 indicators and 20 measures used to score various scenarios or alternatives as sustainability unlikely, sustainability possible, or sustainability likely. The tool was successfully applied as a monitoring and evaluation (M&E) tool for the rural indigenous community of Quebrada Cacao in the province of Bocas del Toro in Panama. A total of 5 alternatives scenarios with estimated costs, labor expenditure and environmental impact were developed using EPANET and SimaPro to help improve the community’s rural spring-sourced gravity-fed community managed water system. Using analytical hierarchy process with weights set by three stakeholder groups in Panama (Quebrada Cacao’s water committee, Panama’s Ministry of Health, and Peace Corps Panama), these five alternative scenarios were scored using the Decision-Making Tool. As a result, a feasible alternative was recommended for the community of Quebrada Cacao using the developed Decision-Making Tool. The tool was also successfully applied as a monitoring and evaluation tool, providing a baseline to develop applicable alternatives to improve the community’s sustainability score. This Decision-Making Tool fulfills an important gap useful for both planning and monitoring and evaluation. It provides a successful tool for application in Panama for building or rehabilitating rural spring-sourced gravity-fed community managed water systems and for other countries with a similar context. Finally, the tool also considers technical, economic, social, and environmental factors, ensuring a more holistic definition of sustainability when building or rehabilitating these water systems. Overall, this Decision-Making Tool can help reduce the number of people without access to safe drinking water around the world and also help ensure systems function sustainably for the long term.
177

Selected aspects of educational philosophy with particular reference to their implementation in the basic education program at Jinks Junior High School, Panama City, Florida

Unknown Date (has links)
Every teacher has what he assumes to be a philosophy of education; frequently it is a composite of aspects of conflicting philosophies of education. This philosophy may be virtually unexamined in that little thought is given to its underlying assumptions and its implications for teaching practices. However, everything the teacher does, every technique and method he employs is drawn from or based upon assumptive concepts of his philosophy or conflicting philosophies of education. Without philosophy, which may be considered in terms of its standard of values, every teacher lacks a point of reference from which to orient the education of young people. He is without a defensible method of evaluation or means of interpreting the goals and aims set up as guides in education. Hence, the vital importance of an integrated philosophy or system of values that will give direction to everyday thinking and that will, in reality, constitute an inclusive way of life. / "June 6, 1953." / Typescript. / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the degree of Master of Science." / Includes bibliographical references (leaves 53-54).
178

Developing Extensions to the Walker-Unger Model in Consideration of the Panama Papers Leaks

Delory, Algot, Matusevicius, Tadas January 2023 (has links)
In 2016, the ICIJ independent organization released the leaks of the Panama Papers. Using the data presented, this thesis aims to evaluate and examine the models developed for the quantification of money laundering, analyze the variables that define the appeal of certain tax havens, and develop extensions to the Walker-Unger model. The proportion of illicit funds flowing from a source country to a host country was calculated using the Walker-Unger model as a reference while considering 35 source and 10 host countries. The variables were adjusted for statistical analyses input through multiple fractional probit regressions, and the outcome was compared to the original Walker-Unger estimates. At a 5% significance level, the research found significance between the account proportion and the independent variables. Furthermore, the evidence showcased more significant values obtained with the regression model, implying that the Walker-Unger model has become irrelevant in this modern era. Due to the following reasons, this study provides a perspective into improving the model through several recommendations.
179

Go Fish: An Analysis Of Economic Rents In Panamanian Fisheries Against Ecosystem Service Values

Glassner, David 01 January 2013 (has links)
Global demand of fish for consumption in developing nations is expected to continue to rise in the near future, putting pressure on stocks that are already overexploited. In the territorial waters of Panama there is a constant struggle between commercial vessels with high yield, subsistence fishermen trying to feed a remote village, and ecosystem services struggling to sustain themselves. These services are the direct and indirect benefits received by the population in the form of food, raw materials, nutrient cycling, and disaster regulation. They are being degraded by illegal and unregulated fishing, bottom trawlers raking the benthos and destroying coral reefs, longlines responsible for thousands of sea turtle and bird deaths, and purse seines that decrease species biodiversity in fish stock. While the government has passed laws to reduce the environmental impact the industrial fisheries have, they lack effective enforcement. An alternative approach is to place monetary values on ecosystem services to show the monetary value of previously unrepresented natural capital. Application of this method to fisheries management can educate policy makers on the economic losses to expect if overfishing of the seas continues and provide the economic imperative to lessen impacts on oceanic ecosystems. Through comparative analysis it is shown that the market value of all fish catch in Panamanian waters is less than that which is provided by the ecosystem services in the area. Open ocean and coral reef ecosystem services provide a combined $103 billion per year while the highest grossing fish catch in Panamanian waters managed to net $356 million in 2004. There is an economic and political imperative to protect and promote sustainability of not only the fish stock, but all ecosystem services in the ocean.
180

Environmental Security In The Global Capitalist System: A World-systems Approach And Study Of Panama

Freeman, Mark Allen 01 January 2007 (has links)
The current global capitalist system is at odds with environmental protection and the protection of indigenous people that are directly linked to the land on which they live. In environmental security literature, many have argued that, theoretically and functionally, it is possible to link national security with environmental security. However possible this may be on paper, in practice, the global capitalist system prevents this from becoming a reality. Using a world-systems approach, this thesis will show that core countries seeking to expand capital by tapping into new markets, locating new sources of raw materials and even forming strategic military partnerships in periphery countries unavoidably degrade the natural environment and thus, adversely affect the lives and health of indigenous people. It is also the argument in this paper that the primary purpose of strategic military partnerships with periphery states, such as those formed in Panama and Colombia, are primarily meant to protect economic interests, thus perpetuating the capitalist cycle. The end result is that, while it is theoretically possible, through a different theoretical lens, to bridge the definitional and theoretical gulf between national security and environmental security, the reality of the system subverts this endeavor, and will continue to do so under its current configuration.

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