949 resultados para Exotic quarkonia


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Die kollineare Laserspektroskopie hat sich in den vergangenen drei Jahrzehnten zur Bestimmung der Kernladungsradien mittelschwerer und schwerer kurzlebiger Atomkerne in ausgezeichneter Weise bewährt. Auf die Isotope sehr leichter Elemente konnte sie allerdings erst kürzlich erweitert werden. Dieser Bereich der Nuklidkarte ist von besonderem Interesse, denn die ersten ab-initio Modelle der Kernphysik, die den Aufbau eines Atomkerns basierend auf individuellen Nukleonen und realistischenWechselwirkungspotentialen beschreiben, sind gegenwärtig nur für die leichtesten Elemente anwendbar. Außerdem existiertrnin dieser Region eine besonders exotische Form von Atomkernen, die sogenanntenrnHalokerne. Die Isotopenkette der Berylliumisotope zeichnet sich durch das Auftreten des Ein-Neutronen Halokerns 11Be und des Zwei- oder Vier-Neutronen-Halos 14Be aus. Dem Isotop 12Be kommt durch seine Position zwischen diesen beiden Exoten und den im Schalenmodell erwarteten magischen Schalenabschluss N = 8 eine besondere Bedeutung zu.rnIm Rahmen dieser Arbeit wurden mehrere frequenzstabilisierte Lasersysteme für die kollineare Laserspektroskopie aufgebaut. An TRIGA-SPEC stehen nun unter anderem ein frequenzverdoppeltes Diodenlasersystem mit Trapezverstärker und frequenzkammstabilisierter Titan-Saphirlaser mit Frequenzverdopplungsstufe für die Spektroskopie an refraktären Elementen oberhalb von Molybdän zur Verfügung, die für erste Testexperimente eingesetzt wurden. Außerdem wurde die effiziente Frequenzvervierfachung eines Titan-Saphirlasers demonstriert. An ISOLDE/CERN wurde ein frequenzkammstabilisierter und ein jodstabilisierter Farbstofflaser installiert und für die Laserspektroskopie an 9,10,11,12Be eingesetzt. Durch das verbesserte Lasersystem und den Einsatz eines verzögerten Koinzidenznachweises für Photonen und Ionen gelang es die Empfindlichkeitrnder Berylliumspektroskopie um mehr als zwei Größenordnungen zu steigern und damit die früheren Messungen an 7−11Be erstmals auf das Isotop 12Be auszuweiten. Außerdem wurde die Genauigkeit der absoluten Übergangsfrequenzen und der Isotopieverschiebungen der Isotope 9,10,11Be signifikant verbessert.rnDurch den Vergleich mit Ergebnissen des Fermionic Molecular Dynamics Modells kann der Trend der Ladungsradien der leichteren Isotope durch die ausgeprägte Clusterstruktur der Berylliumkerne erklärt werden. Für 12Be wird ersichtlich, dass der Grundzustand durch eine (sd)2 Konfiguration statt der vom Schalenmodell erwarteten p2 Konfiguration dominiert wird. Dies ist ein klares Indiz für das bereits zuvor beobachtete Verschwinden des N = 8 Schalenabschlusses bei 12Be.

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Lo studio si tratta di mettere in evidenza il cambiamento che ha subito il termine Oriente nel secolo XX in alcuni testi della letteratura italiana contemporanea. L’opera di Edward Said, L’Orientalismo è un testo di riferimento per i nostri studi. Nel quale abbiamo focalizzato l’attenzione su alcuni aspetti salienti: il concetto di orientalismo; l’interesse nei confronti dell’Oriente sul piano politico, scientifico, letterario; l’impossibilità di separare lo studioso dalle circostanze biografiche e sociali. Siamo riusciti, quindi, a stabilire che il cambiamento dell’immagine orientale dipende da tre fattori: lo scrittore (emittente), il soggetto (la fonte) ed il lettore (destinatario), dai quali si origina l’oggetto (il testo). Basandoci su questi tre elementi abbiamo cercato di inquadrare l’interesse letterario per l’Oriente vista da una triplice prospettiva: imperialismo, fascino ed erotismo. Per studiare le prime due prospettive, abbiamo scelto due opere. La prima presenta l’immagine dell’imperialismo, si tratta di Sanya, La moglie egiziana e il Romanzo dell’Oriente Moderno (1927) di Bruno Corra. La seconda prospettiva dove troviamo l’immagine dell’Oriente fascinoso è nello scritto di Annie Vivanti, La terra di Cleopatra (1925). Il punto centrale della tesi si tratta di studiare Annie Messina (1910-1996), è una scrittrice che ha uno stile peculiare ed un approccio tutto suo al tema dell’Oriente. I testi studiati sono : "Il mirto e la rosa" (1982), "Il banchetto dell'emiro" (1997) e "La principessa e il wâlî" (1996), tutti pubblicati dalla casa editrice Sellerio.L’unico pubblicato da Mondadori è "La palma di Rusafa" (1989). L’ultima parte del lavoro abbiamo esposto un profilo storico e socio-religioso della letteratura erotica araba. In cui abbiamo rintracciato le origini dell’immagine erotico dell’Oriente e il tema dell’omosessualità, mettendo a confronto il testo omosessuale di Messina con la letteratura italiana contemporanea.

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The complex nature of the nucleon-nucleon interaction and the wide range of systems covered by the roughly 3000 known nuclides leads to a multitude of effects observed in nuclear structure. Among the most prominent ones is the occurence of shell closures at so-called ”magic numbers”, which are explained by the nuclear shell model. Although the shell model already is on duty for several decades, it is still constantly extended and improved. For this process of extension, fine adjustment and verification, it is important to have experimental data of nuclear properties, especially at crucial points like in the vicinity of shell closures. This is the motivation for the work performed in this thesis: the measurement and analysis of nuclear ground state properties of the isotopic chain of 100−130Cd by collinear laser spectroscopy.rnrnThe experiment was conducted at ISOLDE/CERN using the collinear laser spectroscopy apparatus COLLAPS. This experiment is the continuation of a run on neutral atomic cadmium from A = 106 to A = 126 and extends the measured isotopes to even more exotic species. The required gain in sensitivity is mainly achieved by using a radiofrequency cooler and buncher for background reduction and by using the strong 5s 2S1/2 → 5p 2P3/2 transition in singly ionized Cd. The latter requires a continuous wave laser system with a wavelength of 214.6 nm, which has been developed during this thesis. Fourth harmonic generation of an infrared titanium sapphire laser is achieved by two subsequent cavity-enhanced second harmonic generations, leading to the production of deep-UV laser light up to about 100 mW.rnrnThe acquired data of the Z = 48 Cd isotopes, having one proton pair less than the Z = 50 shell closure at tin, covers the isotopes from N = 52 up to N = 82 and therefore almost the complete region between the neutron shell closures N = 50 and N = 82. The isotope shifts and the hyperfine structures of these isotopes have been recorded and the magnetic dipole moments, the electric quadrupole moments, spins and changes in mean square charge radii are extracted. The obtained data reveal among other features an extremely linear behaviour of the quadrupole moments of the I = 11/2− isomeric states and a parabolic development in differences in mean square nuclear charge radii between ground and isomeric state. The development of charge radii between the shell closures is smooth, exposes a regular odd-even staggering and can be described and interpreted in the model of Zamick and Thalmi.

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Der Orient als geographischer Topos paust sich durch populäre Medien wie kaum ein anderer. Besonders das Kino vermag es diese Imagination aufscheinen zu lassen. Der cineastisch-imaginierte Orient existiert parallel zur Lebenswelt und konstituiert auf diese Weise eine ganz eigene Wirklichkeit. Gegenstand der Arbeit ist es die Konstruktionsprinzipien des cineastischen Orients zu entschlüsseln sowie eine dafür geeignete Analyseform zu entwickeln. Der Arbeit liegt ein Grundverständnis zugrunde, dass das Unterhaltungskino als ein besonderes Medium alltäglicher Imaginationen betrachtet und auf diese Weise Welt und Wirklichkeit generierend ist. Der empirisch-analytische Teil der Arbeit entwickelt aus tradiertem filmanalytischem Handwerkszeug eine geographische Filmlektüre. Die Analyse, bzw. Lektüre, der ausgewählten Filme durchleuchtet die vom Kino transportierten Mythen und die sich wiederholenden Narrative des cineastischen Orients. Die Lektüre orientiert sich dabei an visuellen und handlungszentrierten filmischen Topoi und liest diese als filmische Standardorte. Zudem werden existierende personengebundene Stereotype herausgearbeitet, die als Grundlage der Kreation des Anderen und als Konstruktionsprinzip des Fremden verstanden werden. Diese haben Konsequenzen für eine filmisch kommunizierte und geschaffene populäre Geopolitik und ermöglichen ein Verständnis der diskursiv-gesellschaftlichen Strukturen der Filme. Die innere Logik des cineastischen Orients ist dabei nicht nur auf Bilder oder nur auf die narrativen Elemente ausgerichtet, sondern erschließt sich aus deren Kombination. Die detaillierte Lektüre der in den Kommunikations-Prozess involvierten Sequenzen und Einstellungen zeigen schließlich, wie die globalen Bilderwelten des Kinos zum Bestandteil einer intermedial hervorgebrachten und im Laufe der Zeit gewachsenen Geographie geworden sind und welche Bedeutung und Funktion die filmimmanente Geographie für die Dramaturgie des cineastischen Orients besitzt.

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Loss of small herbaria is an unfortunate global trend, and initiation of new collections at small academic institutions is an increasingly rare occurrence. In 2006, a new herbarium was established at the State University of New York College at Plattsburgh. The PLAT herbarium has since grown to more than 7,000 specimens, many of them representative of the flora of northeastern New York (especially Clinton County). Previous to 2006, this region was without a recognized herbarium, the nearest in-state collections being more than 150 miles away. Although botanists have previously worked in the region, relatively few plant species were recorded for Clinton County by the New York Flora Atlas – a resource providing species distribution records based on specimens accessioned in herbarium collections. Given the dearth of available distribution data for Clinton County (including the eastern Adirondack Mountains and the western Lake Champlain valley), this project sought to provide records of previously unreported species by comparing NY Flora Atlas maps with current holdings. 203 species will now be added to the NY Flora Atlas for Clinton County, roughly half of those considered exotic. This exercise has amplified the importance of supporting and maintaining small regional herbaria as repositories of valuable biodiversity information. Likewise, this project also highlights the enduring value of training in floristics and taxonomy.

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As the number of solutions to the Einstein equations with realistic matter sources that admit closed time-like curves (CTC's) has grown drastically, it has provoked some authors [10] to call for a physical interpretation of these seemingly exotic curves that could possibly allow for causality violations. A first step in drafting a physical interpretation would be to understand how CTC's are created because the recent work of [16] has suggested that, to follow a CTC, observers must counter-rotate with the rotating matter, contrary to the currently accepted explanation that it is due to inertial frame dragging that CTC's are created. The exact link between inertialframe dragging and CTC's is investigated by simulating particle geodesics and the precession of gyroscopes along CTC's and backward in time oriented circular orbits in the van Stockum metric, known to have CTC's that could be traversal, so the van Stockum cylinder could be exploited as a time machine. This study of gyroscopeprecession, in the van Stockum metric, supports the theory that CTC's are produced by inertial frame dragging due to rotating spacetime metrics.

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Background: Women worldwide use various vaginal practices to clean or modify their vulva and vagina. Additional population-level information is needed on prevalence and motivations for these practices, characteristics of users, and their adverse effects. Methods: This was a household survey using multistage cluster sampling in Tete, Mozambique; KwaZulu-Natal, South Africa; Yogyakarta, Indonesia; and Chonburi, Thailand. In 2006–2007, vaginal practices and their motivations were examined using structured interviews with women 18–60 years of age (n=3610). Results: Prevalence, frequency, and motivations varied markedly. Two thirds of women in Yogyakarta and Chonburi reported one or more practices. In Yogyakarta, nearly half ingest substances with vaginal effects, and in Chonburi, external washing and application predominate. In Tete, half reported three or four current practices, and a quarter reported five or more practices. Labial elongation was near universal, and 92% of those surveyed cleanse internally. Two third's in KwaZulu-Natal practiced internal cleansing. Insertion of traditional solid products was rare in Chonburi and Yogyakarta, but one tenth of women in KwaZulu-Natal and nearly two thirds of women in Tete do so. Multivariate analysis of the most common practice in each site showed these were more common among less educated women in Africa and young urban women in Asia. Explicit sexual motivations were frequent in KwaZulu-Natal and Tete, intended for pleasure and maintaining partner commitment. Practices in Chonburi and Yogyakarta were largely motivated by femininity and health. Genital irritation was common at African sites. Conclusions: Vaginal practices are not as rare, exotic, or benign as sometimes assumed. Limited evidence of their biomedical consequences remains a concern; further investigation of their safety and sexual health implications is warranted.

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Degraded hillsides in Northern Pakistan are rehabilitated through social forestry campaigns using fast growing exotic trees. These plantations on former scrublands curtail access by livestock owned by landless pastoralists and create social tension. This study proposes an alternative strategy of planting indigenous fodder trees and shrubs that are well-suited to the local socio-ecological characteristics and can benefit all social segments. The choice of fodder tree species, their nutritional value and distribution within the complex socio-ecological system is explained. This study also explores the suitability of these trees at different elevations, sites and transhumant routes. Providing mobile herders with adequate fodder trees could relax social tensions and complement food security.

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Companion animals are increasingly brought along by their owners to foreign countries. Thus, small animal travel medicine is becoming more important. The field includes both prophylaxis and metaphylaxis against various infectious diseases, as well as their diagnosis and treatment. Dogs returning from Southern Europe, but also from more tropical regions, may be infected with exotic pathogens. In addition, imported pedigree or working dogs, and especially stray dogs imported through welfare organisations, are at high risk.The present overview summarises the clinical and practical aspects of exotic parasitic diseases that may affect such dogs, and the risk of such diseases becoming autochthonously transmitted in Switzerland. Furthermore, the zoonotic potential of these infections will be considered.

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Invasive and exotic species present a serious threat to the health and sustainability of natural ecosystems. These species often benefit from anthropogenic activities that aid their introduction and dispersal. This dissertation focuses on invasion dynamics of the emerald ash borer, native to Asia, and European earthworms. These species have shown detrimental impacts in invaded forest ecosystems across the Great Lakes region, and continue to spread via human-assisted long distance dispersal and by natural modes of dispersal into interior forests from areas of introduction. Successful forest management requires that the impact and effect of invasive species be considered and incorporated into management plans. Understanding patterns and constraints of introduction, establishment, and spread will aid in this effort. To assist in efforts to locate introduction points of emerald ash borer, a multicriteria risk model was developed to predict the highest risk areas. Important parameters in the model were road proximity, land cover type, and campground proximity. The model correctly predicted 85% of known emerald ash borer invasion sites to be at high risk. The model’s predictions across northern Michigan can be used to focus and guide future monitoring efforts. Similar modeling efforts were applied to the prediction of European earthworm invasion in northern Michigan forests. Field sampling provided a means to improve upon modeling efforts for earthworms to create current and future predictions of earthworm invasion. Those sites with high soil pH and high basal area of earthworm preferred overstory species (such as basswood and maples) had the highest likelihood of European earthworm invasion. Expanding beyond Michigan into the Upper Great Lakes region, earthworm populations were sampled across six National Wildlife Refuges to identify potential correlates and deduce specific drivers and constraints of earthworm invasion. Earthworm communities across all refuges were influenced by patterns of anthropogenic activity both within refuges and in surrounding ecoregions of study. Forest composition, soil pH, soil organic matter, anthropogenic cover, and agriculture proximity also proved to be important drivers of earthworm abundance and community composition. While there are few management options to remove either emerald ash borer or European earthworms from forests after they have become well established, prevention and early detection are important and can be beneficial. An improved understanding the factors controlling the distribution and invasion patterns of exotic species across the landscape will aid efforts to determine their consequences and generate appropriate forest management solutions to sustain ecosystem health in the presence of these invaders.

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Metals price risk management is a key issue related to financial risk in metal markets because of uncertainty of commodity price fluctuation, exchange rate, interest rate changes and huge price risk either to metals’ producers or consumers. Thus, it has been taken into account by all participants in metal markets including metals’ producers, consumers, merchants, banks, investment funds, speculators, traders and so on. Managing price risk provides stable income for both metals’ producers and consumers, so it increases the chance that a firm will invest in attractive projects. The purpose of this research is to evaluate risk management strategies in the copper market. The main tools and strategies of price risk management are hedging and other derivatives such as futures contracts, swaps and options contracts. Hedging is a transaction designed to reduce or eliminate price risk. Derivatives are financial instruments, whose returns are derived from other financial instruments and they are commonly used for managing financial risks. Although derivatives have been around in some form for centuries, their growth has accelerated rapidly during the last 20 years. Nowadays, they are widely used by financial institutions, corporations, professional investors, and individuals. This project is focused on the over-the-counter (OTC) market and its products such as exotic options, particularly Asian options. The first part of the project is a description of basic derivatives and risk management strategies. In addition, this part discusses basic concepts of spot and futures (forward) markets, benefits and costs of risk management and risks and rewards of positions in the derivative markets. The second part considers valuations of commodity derivatives. In this part, the options pricing model DerivaGem is applied to Asian call and put options on London Metal Exchange (LME) copper because it is important to understand how Asian options are valued and to compare theoretical values of the options with their market observed values. Predicting future trends of copper prices is important and would be essential to manage market price risk successfully. Therefore, the third part is a discussion about econometric commodity models. Based on this literature review, the fourth part of the project reports the construction and testing of an econometric model designed to forecast the monthly average price of copper on the LME. More specifically, this part aims at showing how LME copper prices can be explained by means of a simultaneous equation structural model (two-stage least squares regression) connecting supply and demand variables. A simultaneous econometric model for the copper industry is built: {█(Q_t^D=e^((-5.0485))∙P_((t-1))^((-0.1868) )∙〖GDP〗_t^((1.7151) )∙e^((0.0158)∙〖IP〗_t ) @Q_t^S=e^((-3.0785))∙P_((t-1))^((0.5960))∙T_t^((0.1408))∙P_(OIL(t))^((-0.1559))∙〖USDI〗_t^((1.2432))∙〖LIBOR〗_((t-6))^((-0.0561))@Q_t^D=Q_t^S )┤ P_((t-1))^CU=e^((-2.5165))∙〖GDP〗_t^((2.1910))∙e^((0.0202)∙〖IP〗_t )∙T_t^((-0.1799))∙P_(OIL(t))^((0.1991))∙〖USDI〗_t^((-1.5881))∙〖LIBOR〗_((t-6))^((0.0717) Where, Q_t^D and Q_t^Sare world demand for and supply of copper at time t respectively. P(t-1) is the lagged price of copper, which is the focus of the analysis in this part. GDPt is world gross domestic product at time t, which represents aggregate economic activity. In addition, industrial production should be considered here, so the global industrial production growth that is noted as IPt is included in the model. Tt is the time variable, which is a useful proxy for technological change. A proxy variable for the cost of energy in producing copper is the price of oil at time t, which is noted as POIL(t ) . USDIt is the U.S. dollar index variable at time t, which is an important variable for explaining the copper supply and copper prices. At last, LIBOR(t-6) is the 6-month lagged 1-year London Inter bank offering rate of interest. Although, the model can be applicable for different base metals' industries, the omitted exogenous variables such as the price of substitute or a combined variable related to the price of substitutes have not been considered in this study. Based on this econometric model and using a Monte-Carlo simulation analysis, the probabilities that the monthly average copper prices in 2006 and 2007 will be greater than specific strike price of an option are defined. The final part evaluates risk management strategies including options strategies, metal swaps and simple options in relation to the simulation results. The basic options strategies such as bull spreads, bear spreads and butterfly spreads, which are created by using both call and put options in 2006 and 2007 are evaluated. Consequently, each risk management strategy in 2006 and 2007 is analyzed based on the day of data and the price prediction model. As a result, applications stemming from this project include valuing Asian options, developing a copper price prediction model, forecasting and planning, and decision making for price risk management in the copper market.

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The exotic emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), was first discovered in North America in southeastern Michigan, USA, and Windsor, Ontario, Canada in 2002. Significant ash (Fraxinus spp.) mortality has been caused in areas where this insect has become well established, and new infestations continue to be discovered in several states in the United States and in Canada. This beetle is difficult to detect when it invades new areas or occurs at low density. Girdled trap tree and ground surveys have been important tools for detecting emerald ash borer populations, and more recently, purple baited prism traps have been used in detection efforts. Girdled trap trees were found to be more effective than purple prism traps at detecting emerald ash borer as they acted as sinks for larvae in an area of known low density emerald ash borer infestation. The canopy condition of the trap trees was not predictive of whether they were infested or not, indicating that ground surveys may not be effective for detection in an area of low density emerald ash borer population. When landing rates of low density emerald ash borer populations were monitored on non-girdled ash trees, landing rates were higher on larger, open grown trees with canopies that contain a few dead branches. As a result of these studies, we suggest that the threshold for emerald ash borer detection using baited purple prism traps hung at the canopy base of trees is higher than for girdled trap trees. In addition, detection of developing populations of EAB may be possible by selectively placing sticky trapping surfaces on non-girdled trap trees that are the larger and more open grown trees at a site.

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The herbaceous layer is a dynamic layer in a forest ecosystem which often contains the highest species richness in northern temperate forests. Few long-term studies exist in northern hardwood forests with consistent management practices to observe herbaceous species dynamics. The Ford Forest (Michigan Technological University) reached its 50th year of management during the winter of 2008-2009. Herbaceous species were sampled during the summers pre- and post-harvest. Distinct herbaceous communities developed in the 13-cm diameter-limit treatment and the uncut control. After the harvest, the diameter-limit treatments had herbaceous communities more similar to the 13-cm diameter-limit treatment than the uncut control; the herbaceous layer contained more exotic and early successional species. Fifty years of continuous management changed the herbaceous community especially in the diameter-limit treatments. Sites used in the development of habitat classification systems based on the presence and absence of certain herbaceous species can also be used to monitor vegetation change over time. The Guide to Forest Communities and Habitat Types of Michigan was developed to aid forest managers in understanding the potential productivity of a stand, and often aid in the development of ecologically-based forest management practices. Subsets of plots used to create the Western Upper Peninsula Guide were resampled after 10 years. During the resampling, both spring and summer vegetation were sampled and earthworm populations were estimated through liquid extraction. Spring sampling observed important spring ephemerals missed during summer sampling. More exotic species were present during the summer 2010 sampling than the summer 2000 sampling. Invasive European earthworms were also observed at all sample locations in all habitat types; earthworm densities increased with increasing habitat richness. To ensure the accuracy of the guide book, plots should be monitored to see how herbaceous communities are changing. These plots also offer unique opportunities to monitor for invasive species and the effects of a changing climate.

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How do prevailing narratives about Native Americans, particularly in the medium of film, conspire to promote the perspective of the dominant culture? What makes the appropriation of Indigenous images so metaphorically popular? In the past hundred years, little has changed in the forms of representation favored by Hollywood. The introductory chapter elucidates the problem and outlines the scope of this study. As each subsequent chapter makes clear, the problem is as relevant today as it has been throughout the entire course of filmic history. Chapter Two analyzes representational trends and defines each decade according to its favorite stereotype. The binary of the bloodthirsty savage is just as prevalent as it was during the 1920s and 30s. The same holds true for the drunken scapegoat and the exotic maiden, which made their cinematic debuts in the 1940s and 50s. But Hollywood has added new types as well. The visionary peacemaker and environmental activist have also made an appearance within the last forty years. What matters most is not the realism of these images, but rather the purposes to which they can be put toward validating whatever concerns the majority filmmakers wish to promote. Whether naïvely or not, such representations continue to evacuate Indigenous agency to the advantage of the majority. A brief historical overview confirms this legacy. Various disciplines have sought to interrogate this problem. Chapter three investigates the field of postcolonial studies, which makes inquiry into the various ways these narratives are produced, marketed, and consumed. It also raises the key questions of for whom, and by whom, these narratives are constructed. Additional consideration is given to their value as commodities in the mass marketplace. Typically the products of a boutique-multiculturalism, their storylines are apt to promote the prevailing point of view. Critical theory provides a foundational framework for chapter four. What is the blockbuster formula and how do the instruments of capital promote it? Concepts such as culture industry and repressive tolerance examine both the function and form of the master narrative, as well as its use to control the avenues of dissent. Moreover, the public sphere and its diminishment highlight the challenges inherent in the widespread promotion of an alternative set of narratives. Nonetheless, challenges to prevailing narratives do exist, particularly in the form of Trickster narratives. Often subject to persistent misrecognition, the Trickster demonstrates a potent form of agency that undeniably dismantles the hegemony of Western cinema. The final chapter examines some of the Trickster's more subtle and obscure productions. Usually subjugated to the realm of the mystical, rather than the mythical, these misinterpreted forms have the power to speak in circles around a majority audience. Intended for an Other audience, they are coded in a language that delivers a type of direction through indirection, promoting a poignant agency all their own.

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Acer saccharum Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as being the predisposing and inciting factors in different regions at different times. Some of the most common factors attributed to previous maple dieback episodes were insect defoliation outbreaks, inadequate precipitation, poor soils, atmospheric deposition, fungal pathogens, poor management, or a combination of these. The current sugar maple dieback was evaluated to determine the etiology, severity, and change in dieback on both industry and public lands. A network of 120 sugar maple health evaluation plots was established in the Upper Peninsula, Michigan, northern Wisconsin, and eastern Minnesota and evaluated annually from 2009-2012. Mean sugar maple crown dieback between 2009-2012 was 12.4% (ranging from 0.8-75.5%) across the region. Overall, during the sampling period, mean dieback decreased by 5% but individual plots and trees continued to decline. Relationships were examined between sugar maple dieback and growth, habitat conditions, ownership, climate, soil, foliage nutrients, and the maple pathogen sapstreak. The only statistically significant factor was found to be a high level of forest floor impacts due to exotic earthworm activity. Sugar maple on soils with lower pH had less earthworm impacts, less dieback, and higher growth rates than those on soils more favorable to earthworms. Nutritional status of foliage and soil was correlated with dieback and growth suggesting perturbation of nutrient cycling may be predisposing or contributing to dieback. The previous winter's snowfall totals, length of stay on the ground, and number of days with freezing temperatures had a significant positive relationship to sugar maple growth rates. Sapstreak disease, Ceratocystis virescens, may be contributing to dieback in some stands but was not related to the amount of dieback in the region. The ultimate goal of this research is to help forest managers in the Great Lakes Region prevent, anticipate, reduce, and/or salvage stands with dieback and loss in the future. An improved understanding of the complex etiology associated with sugar maple dieback in the Upper Great Lakes Region is necessary to make appropriate silvicultural decisions. Forest Health education helps increase awareness and proactive forest management in the face of changing forest ecosystems. Lessons are included to assist educators in incorporating forest health into standard biological disciplines at the secondary school curricula.