An increasing amount of evidence suggests that as temperatures increase, montane animals are moving upward in elevation (IPCC 2007, Parmesan and Yohe 2003). As suitable habitats rise in elevation and then disappear altogether, these animals could be pushed to extinction. The American pika, Ochotona princeps, is a montane mammal that lives in western North America, usually at elevations above 1500 m (Smith and Weston 1990). Recent evidence suggests that pika population numbers are dropping in response to rising temperatures (Beever et al. 2010). The pika is a small herbivorous lagomorph, a relative of hares and rabbits. Its habitat is tightly restricted to talus slopes (rockfields) and the surrounding vegetation (Grayson 2005). Pikas have a high tolerance for cold temperatures, and do not hibernate during the long montane winter. However, they have very little tolerance for even mildly warm temperatures, and have been found to die when confined above ground at 25.5˚ C (Smith 1974b). To better understand pika persistence, we resurveyed 17 historic pika sites in the Lassen Peak region of northern California in August and September, 2009. Six of the historic sites were abandoned, as well as an additional 11 of 17 new sites surveyed. At each site we collected habitat information, and analyzed the data for factors that were correlated with site occupancy. We also installed 38 iButton thermal dataloggers in abandoned and occupied pika use sites, to determine if temperature affects occupancy. The dataloggers remained in pika sites for 14 months and recorded temperature every 1.5 hours. Abandoned pika sites had higher average temperatures and more days below 0˚ C. They also had greater shrub cover, less forb and graminoid cover, and a greater percentage of litter substrate. These findings suggest that the current warming trend may be having a negative impact on pikas in the Lassen Peak Region. As temperatures rise, pikas may be declining due to unsuitable temperatures and altered vegetative communities. In addition to the Lassen surveys, I investigated pika behavior in different temperature regimes in the Sierra Nevada. If pikas are able to adapt to climate change, it is possible that populations of pikas in different temperature regimes may exhibit behavioral plasticity, or have evolved genetic differences, such that these populations have different daily activity schedules. To determine if there is a difference in pika behavior at different elevations I observed pikas in one low and one high elevation site within the Bishop Creek drainage system in the Sierra Nevada. I conducted behavioral observations of pikas in four time blocks throughout the day in August and September, 2010. I recorded specific behaviors, such as foraging and haying (vegetation collecting), and compared these activities between low and high elevation pikas at different times of day. In August, pikas in the low elevation site exhibited a different activity profile than those in the high elevation site. Low elevation pikas were significantly more crepuscular (most active at dawn and dusk) during this month. I also observed more foraging behavior in the high elevation than the low elevation site, in both August and September. Reduced activity at higher temperatures may have negative impacts on pikas as temperatures increase. Low elevation pikas may be stressed due to reduced time spent foraging and haypile (overwinter vegetation cache) gathering. However, if pikas were able to switch their activity schedules to a more nocturnal schedule, they could escape higher daytime temperatures. To detect the possibility of nocturnal behavior in low elevation pikas, I set up four infra-red remote cameras in the low elevation site. I had variable success in capturing pika behavior with the cameras, and detected no evidence of nocturnal behavior. More research on the possibility of nocturnal behavior in pikas would be worthwhile, in part to determine what chance, if any, pikas have of adapting to rising global temperatures.

Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / To describe the structural strains and cultural conflicts that take place when two social systems confront each other, the concept of Transitional Role was used to analyze the sociological adaptation in the social system, and the concept of Perceptual Distortion of Transitional Roles by different groups was usee to analyze the strain and conflict that continued. In order to locate, describe and analyze Transitional Roles in Ghana, Nigeria and Sierra Leone, the social science reserach in five categories of Husbands and Wives, Buyers and Sellers, Priests and Pastors, Administrators and Agitators and Servants and Masters was examined. In order to evaluate the Perceptual Distortion of the Transitional Roles described, the available social science reserach was compared with two samples of novels (those by West Africans and those by Europeans) about West Africa. The following were the findings: (1) Social strain and culture conflict affect both groups, West African and European. (2) Social strains exist in all the above aspects of colonial life. (3) Despite severe dual systemic strain, the colonial social system operated as one viable social system. (4) Not all social strains are resolved immediately by the creation of Transitional Roles and therefore, the historical development of Transitional Roles indicates that they continue to change. (5) Social circles formed around transitional roles and as these social circles proliferated, the basis of a new society was established. Thus a positive resolution of social strain has been located and described in the development of Transitional Roles. The findings of this study resulting from the application of Levels of Transition to culture conflict indicate that: (1) the European novelists see culture conflict as maladjustment existing with the individual African either in the form of reversion to an earlier evolutionary stage or in the form of poor imitation of British culture; and they do not see their own involvement in culture conflict; (2) the African novelists, in contrast, locate culture conflict between the various Levels of Transition or within social relationships between the numerous West African social circles, and secondarily between British and West African Transitional Roles. The findings of this study resulting from the evaluation of Perceptual Distortion suggest that (1) Transitional Role incumbents are more accurate observers than are stabilized role incumbents. (2) Perceivers observe members of their own social system of origin more accurately than they perceive a foreign social system. (3) Segregation, "Time Lag" and ideology distort perception. This analysis substantiates the proposition that novels are of limited value as sources of sociological insights unless they are compared with social science research and unless the orientation in terms of social membership of the novelist is known. The reading public in the est, to the extent that it has depended upon European novels as its source of information about West Africa, is inadequately informed. Americans who rely on this fictional material have looked at West Africa primarily through European eyes. / 2031-01-01

The main purpose of this research was to understand the civil war in Sierra Leone and its antecedents, and to analyse the package of reconstruction reforms which came along in the post-war era and their relevance for and impact on the local challenges for longer term peace. Continued corruption among the political class, the persistent disenfranchisement of important social groups, and emerging tensions along political party lines suggested that, ten years on from the Lomé Peace Accord, there may have been a malaise in the peacebuilding plan. To investigate the complex issues, and to support the hypothesis that the model for reconstruction was not best suited to local conditions and local priorities, the work first made a deep interrogation of the historic political, cultural and economic factors which led to the violent conflict. This scrutiny of the local experience allowed the conceptualisation of a germane ¿framework for peace` which represented the most pressing priorities of the local community and the central challenges for peace. The framework reflected the main concerns of the local populace and was used as an analytical tool to better understand the relevance of the model for reconstruction vis-à-vis the local context. Through a critical analysis of the post-war reforms and their impact on the social dimensions of recovery, in particular macro-economic reforms and the promotion of democracy, conclusions were drawn about the appropriateness and efficacy of the model of reconstruction experienced in Sierra Leone and how it supported local priorities for peace. The enquiry found that, in general, the model for reconstruction was not best suited to the local context because of its inflexibility to support the local peacebuilding and its many challenges. In some ways the model for reconstruction heightened residual tensions from the conflict because it failed to address key issues for reform such as governance and social justice. / Economic and Social Research Council

Over the last two decades the frequency of humanitarian interventions in Africa, delivered by a wide range of actors, has increased. The British military intervention in the Sierra Leonean civil war in the early 2000s is often cited as an example of successful intervention and solidified Security Sector Reform (SSR) as a key component of state-building and development. Yet in-depth analysis of the long-term legacies of this ‘successful’ intervention are sparse and there remains a notable dearth in research exploring the British involvement from the perspectives of those directly involved or affected. This qualitative research provides a novel outlook by exploring micro-level experiences, thus addressing this lacuna through examining the legacies within Sierra Leone and in British foreign policy from an experiential perspective. The Responsibility to Protect (R2P) is used as a framework in order to draw out implications for global intervention practice, as arguably R2P must also be accompanied by a responsibility to fully understand the legacy of this social phenomenon. A themed analysis of original data explores the link between official narratives and the perspectives of those on the ground, often exposing a disconnect and identifying important nuances within the interpretation of the success of the British intervention. Through a critical analysis of these experiences significant questions are raised regarding the dynamics between intervening forces and the affected population; perceptions of legitimacy; accountability; and the implications for R2P more broadly.

Liberal peacebuilding, the means by which transition societies can be reconfigured and reconstructed to bring about lasting peace, focussed on chieftaincy reform and decentralization as part of the peacebuilding package in Sierra Leone. The main focus of this research is to explore the efficacy of these structures as durable peacebuilding mechanisms in a transition society like Sierra Leone. The core argument is that liberal peacebuilding based on the reform of chieftaincy and decentralisation has failed to deliver effective peacebuilding mechanisms in Sierra Leone. Chieftaincy reform should have taken into consideration the specific context of the nature of chieftaincy in the country which in most cases transcends issues of leadership to one of collective identity. The decentralisation process is also fraught with a host of problems ranging from tension between the councils and the chiefs on the one hand, to the unwillingness on the part of central government to cede some of its powers to the local government. The control of central government over the councils and the decentralisation process is still very visible. The relevance of this research is that it enhances our understanding of key debates and policy intervention practices on post-war peacebuilding and state reconstruction in transition societies. It also contributes to the existing literature on post-conflict peacebuilding by positing that there is a huge challenge to the Liberal Peace paradigm in bringing about peace in war-torn societies. / Commonwealth Commission

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This essay attempts to discuss the decolonial memorialscape in Germany and Sierra Leone, bringing into focus the few existing examples. Coming from the visual arts, my wish is to bring art-practice into the communication for development feld. This means allowing associations, emotions and subjective observations to be part of the research on memorial-cultures, understanding images and layout as integral parts of a political-aesthetic thesis. The examples from Germany and Sierra Leone are not only understood in their national frameworks, but rather in their un/common coloniality. The essay explores at frst the material world of colonial-critical memorials, an undertaking that I deemed to be achievable in view of the limited number of memorials both countries have. The research feld is still very complex and therefore the essay itself is a condensed and fragmented frst step along peripheral paths. Listening to voices from Freetown as well as observing activities around a memorial in the German city of Bremen helped me gain an enlarged understanding of memorials. Communication aspects and performative approaches surrounding a sculptural form are able to give memorials living and discursive dimensions. The hypothesis that memorials could be helpful for the decolonialization of colonizing – as well as colonized - societies could not be fully answered as the examples described all have their weaknesses. If immaterial, sometimes ephemeral forms like writings, theatre, activism and spiritual ceremonies are included in the memorialscape, the answer is clearly positive, even though the majority in Germany would not be reached by these actions. In contrast to Germany, in Sierra Leone I found a millieux de mémoire (Pierre Nora) which might not be that active in the defnition of Aleida Assmann, but which, with the empowering impacts of the West African concept of Sankofa, is able to create creole realms of memory. Besides the image of the path along the fragmented, multilingual Dékolonεlízashɔn process, different bodies of water became powerful imaginations for decolonial memorials, connecting different times and places. The element of water itself is a palimpsest and at the same time an unchanging Mahnmal. A Mahnmal which is absent from the collective memory (Maurice Halbwachs) in Germany and can therefore be perceived as a void – unlike in the collective memory-culture of The Black Atlantic (Paul Gilroy). With reference to the examples described and analyzed, proposals are included and put forward for discussion.

The current scale and scope of peacekeeping missions is unprecedented and with this increasing reliance on peacekeeping as a tool to manage threats to peace and security come questions about who should keep the peace. Is it, as many assume, the United Nations? Is it a regional organization, such as the African Union? Or is it an individual state? Each of these different types of peacekeeping operations have different strengths and weaknesses associated with them in terms of legitimacy, institutional capacity, local and regional awareness, resources, and military effectiveness. This dissertation analyzes types of peacekeeping operations to determine which is the most effective in restoring peace and stability and why. I use a structured, focused comparative case study methodology to examine eight cases of peacekeeping, across two countries, the Democratic Republic of Congo and Sierra Leone, each of which has been subject to all three types of peacekeeping operations. This approach allows me to hold a number of control variables constant, providing a clear test of the impact of the type of intervention. I found that the type of PKO makes a difference to the success or failure of that mission. PKOs run by lead states are more likely to be successful because they are more willing to use force and they are more likely to have the resources and capabilities necessary to implement that force. Further, I found that two types of PKOs working together can use their strengths to compensate for each other’s weaknesses. I also present a quantitative study with a larger sample size that both substantiates my findings and allows me to generalize them to a wider universe of cases. / Political Science

En este trabajo de tesis se seleccionaron tres especies entre nueve recolectadas en las Sierras Australes Bonaerenses, cuyos extractos mostraron inhibición de la enzima acetilcolinesterasa (ACE): Senecio ventanensis, Grindelia argentina y Grindelia ventanensis. No se hallaron antecedentes fitoquímicos o de actividades biológicas en literatura de estas asteráceas endémicas. Mediante el fraccionamiento bioguiado de los extractos activos se buscó aislar los metabolitos secundarios responsables de la actividad inhibitoria de ACE. Los alcaloides pirrolizidínicos N-óxido de usaramina (1), N-óxido de retrorsina (2) y N-óxido de integerrimina (3) fueron aislados a partir del extracto etanólico de S. ventanensis y un par de diastereoisómeros del 3,6-epidioxi-1,10-bisaboladieno (4 y 5) a partir de su sub-extracto diclorometánico. Por otra parte, distintos ácidos clorogénicos fueron detectados en fracciones activas del sub-extracto butanólico de G. argentina: ácido 5-Ocafeoilquínico (6), ácido 5-O-p-cumaroilquínico (7), ácido 5-O-p-feruloilquínico (8) y ácido-3,5- dicafeoil-epi-quínico (9). Por último, el fraccionamiento bioguiado del extracto etanólico de G. ventanensis, el más activo, condujo al aislamiento de un diterpenoide labdano de la serie normal identificado como ácido 17-hidroxicatívico (10). Considerando la actividad anticolinesterasa de 10 y su extracción sencilla y en buen rendimiento, se prepararó una serie de veinte derivados nuevos del ácido catívico (16-19) a través de transformaciones sobre el grupo carboxilo (C15) de 10, introduciendo un espaciador de 2 a 6 carbonos y una amina terciaria. La mayoría de los derivados fueron más activos que el compuesto natural 10. El derivado con un anillo de pirrolidina unido al diterpenoide por un espaciador de cuatro carbonos (16c) fue el inhibidor más potente tanto de ACE como de butirilcolinesterasa; asimismo mostró inhibición significativa de ACE en células de neuroblastoma humanas SH-SY5Y, sin efecto citotóxico. El estudio cinético enzimático y el modelado molecular revelaron que 16c se une tanto al sitio activo catalítico como al sitio aniónico periférico de ACE. Por otro lado, los derivados 11-14 se obtuvieron mediante transformaciones químicas sencillas de 10, pero su actividad inhibitoria de ACE no fue mejorada por las derivatizaciones realizadas. La inhibición de la producción de óxido nítrico (NO) observada para el extracto etanólico de G. argentina llevó a su fraccionamiento bioguiado, permitiendo el aislamiento de tres saponinas tipo oleanano nuevas, grindeliósidos A-C (20-22), y una flavona conocida, hispidulina (23). Los metabolitos fueron evaluados por su actividad inhibitoria de la producción de NO inducida por LPSIFN- g en macrófagos RAW264.7 y por su actividad citotóxica contra la línea celular de leucemia humana CCRF-CEM y de fibroblastos de pulmón MRC-5. Hispidulina redujo marcadamente la producción de NO inducida por LPS-IFN-g, mientras que grindeliósidos A-C mostraron citotoxicidad, siendo grindeliósido C el más activo contra ambas líneas celulares. / In this work three of nine species collected in the Sierras Australes Bonaerenses were selected because of the acetylcholinesterase (AChE) inhibition showed by their extracts: Senecio ventanensis, Grindelia argentina y Grindelia ventanensis. There is no phytochemical or biological activities previous record in the literature for these endemic species of the Asteraceae family. The isolation of the metabolites responsible of the activity was conducted by a bioassay guided fractionation. The pyrrolizidine alkaloids usaramine N-oxide (1), retrorsine N-oxide (2) and integerrimine N-oxide (3) were isolated from the ethanolic extract of S. ventanensis and a pair of distereoisomers of 3,6-epidioxy-1,10-bisaboladiene (4 and 5) from its dichloromethane sub-extract. Additionally, different chlorogenic acids were detected in the active fractions of G. argentina butanolic sub-extract: 5-O-caffeoylquinic acid (6), 5-O-p-coumaroylquinic acid (7), 5-O-feruloylquinic acid (8), and 3,5-dicaffeoyl-epi-quinic acid (9). Finally, the bioactivity guided fractionation of the ethanolic extract of G. ventanensis, the most active one, led us to isolate a normal labdane diterpenoid identified as 17-hydroxycativic acid (10). Taking into account the anticholinesterase activity of 10 and its easy extraction in good yield, a set of twenty new cativic acid derivatives (16-19) was prepared from 10 through transformations on the carboxylic group at C15, introducing a C2-C6 linker and a tertiary amine group. Most of the tested compounds were better AChE and butyrylcholinesterase (BChE) inhibitors than the natural diterpenoid 10. The derivative with a four carbon spacer and a pyrrolidine moiety (16c) was the most potent AChE and BChE inhibitor; in addition it exhibited significant inhibition of AChE activity in SHSY5Y human neuroblastoma cells and was non-cytotoxic. Enzyme kinetic studies and molecular modeling revealed that 16c targeted both the catalytic active site and the peripheral anionic site of AChE. On the other hand, derivatives 11-14 were obtained through simple structural modifications of 10, but their AChE inhibitory activity was not improved by the derivatizations. The inhibitory activity of nitric oxide (NO) production of the ethanolic extract of G. argentina prompted us to isolate three new oleanane-type saponins, grindeliosides A-C (20-22), and a known flavone, hispidulin (23). The isolated compounds were evaluated for their inhibitory activities against LPS/IFN-g induced NO production in RAW 264.7 macrophages and for their cytotoxic activities against the human leukemic cell line CCRF-CEM and MRC-5 lung fibroblasts. Hispidulin markedly reduced LPS/IFN- g induced NO production while grindeliosides A–C were found to be cytotoxic, with grindelioside C being the most active against both cell lines.