7 resultados para STAR-FORMATION HISTORY

em Digital Commons at Florida International University


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Star formation occurs when the gas (mostly atomic hydrogen; H I) in a galaxy becomes disturbed, forming regions of high density gas, which then collapses to form stars. In dwarf galaxies it is still uncertain which processes contribute to star formation and how much they contribute to star formation. Blue compact dwarf (BCD) galaxies are low mass, low shear, gas rich galaxies that have high star formation rates when compared to other dwarf galaxies. What triggers the dense burst of star formation in BCDs but not other dwarfs is not well understood. It is often suggested that BCDs may have their starburst triggered by gravitational interactions with other galaxies, dwarf-dwarf galaxy mergers, or consumption of intergalactic gas. However, there are BCDs that appear isolated with respect to other galaxies, making an external disturbance unlikely.^ Here, I study six apparently isolated BCDs from the LITTLE THINGS sample in an attempt to understand what has triggered their burst of star formation. LITTLE THINGS is an H I survey of 41 dwarf galaxies. Each galaxy has high angular and velocity resolution H I data from the Very Large Array (VLA) telescope and ancillary stellar data. I use these data to study the detailed morphology and kinematics of each galaxy, looking for signatures of starburst triggers. In addition to the VLA data, I have collected Green Bank Telescope data for the six BCDs. These high sensitivity, low resolution data are used to search the surrounding area of each galaxy for extended emission and possible nearby companion galaxies.^ The VLA data show evidence that each BCD has likely experienced some form of external disturbance despite their apparent isolation. These external disturbances potentially seen in the sample include: ongoing/advanced dwarf-dwarf mergers, an interaction with an unknown external object, and external gas consumption. The GBT data result in no nearby, separate H I companions at the sensitivity of the data. These data therefore suggest that even though these BCDs appear isolated, they have not been evolving in isolation. It is possible that these external disturbances may have triggered the starbursts that defines them as BCDs.^

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This study inquires into the institutional identity of the Church of Jesus Christ of Latter-day Saints since its founding in 1830. The study takes a historical stance in discussing the relationship between American public perceptions and the Church's developing internal identity, tracing these changes through three distinct historical stages. Building on the works of historians and sociologists such as Jan Shipps, Armand Mauss, and Terryl Givens, this study hopes to contribute to the understanding of new religious movements and the progression from sect to church. The study finds that Mormon identity and American perceptions of Mormons have had an inter-influential relationship, each responding and re-forming in turn. The LDS Church has progressed from sect to church as tensions with the host society have lessened. Currently, the Church is at an optimum level of tension with the host society, maintaining a distinct identity while enjoying conventional acceptance.

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This study examined the perceptions of state governmental officials and administrators from the state university system, community college system, and independent institutions concerning the ability of various groups to influence state-level higher education policy formation. The study was conducted in Florida for the period 1989-94. Florida has a history of legislative involvement in higher education, a unique system of state universities and community colleges, and a limited number of private institutions of higher education. This study was grounded in the works of Mortimer and McConnell (1978), Millett (1987), Marshall, Mitchell, and Wirt (1989) and Finitfer, Baldwin, and Thelin (1991).^ The study represented the application of an embedded, single-case design. A survey was the primary collection instrument. Respondents were asked questions concerning: (a) personal involvement in higher education, (b) perceptions of the ability of various groups to influence higher education policy, (c) the names of particular individuals considered key players in higher education policy formation, (d) important state-level documents, (e) personal knowledge of key areas of policy formation, and (f) emerging higher education issues in Florida. Quantitative and qualitative methods were used to analyze the different sections of the survey.^ The findings indicated that a power and influence hierarchy exists among the various groups that attempt to influence higher education policy and that this hierarchy is recognized by state government officials and higher education administrators. While an analysis of variance of the various groups revealed a few differences between state government officials and higher education personnel, the high overall agreement was an important finding. Leading members of the legislature, especially the Chair of the Senate Higher Education Committee, and key staff members, especially from the Senate Ways & Means Committee, were considered the most influential. Representatives from higher education institutions and research organizations were considered among the least influential. Emerging issues identified by the respondents included: (a) the political nature of state-level policy formation, (b) the role of legislative staff, (c) the competition for state moneys, (d) legislative concern for state-wide budgetary efficiency, and (e) legislative attempts to define quality and supervise academic program development for higher education. ^

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Desegregation of social and public spaces was the most visible result of the Civil Rights Movement. After 1960, the integration of schools in Mississippi became a source of conflict. The social change of Civil Rights attacked the social order of White Resistance that supported the state superstructure. The public schools were a place for the discovery of identity for Blacks. The integrated on of the schools caused many Whites to leave rather than be integrated with Blacks. Desegregation of schools was also a slow process because the local and state government could not enforce the decisions of the US Courts, leading Blacks to realize their place in American society could only be secured through individual action. ^ This work explains the role of schooling during the integration of the Holly Springs Separate School System. The process of forging a new identity by local Blacks is examined against the forces of social change and resistance. I addition, this work examines the perils for the Blacks as they faced the uncertainty of change in the crucial Civil Rights years between 1964 and 1974. ^ This work analyzes how the Black community dealt with the problems triggered by the desegregation of the school system in Holly Springs, of a constructed social condition, a psychological state of being, the realities of racism and segregation, and the change and resistance between the individual and the collective. It is based on six months of field work investigation. Although the schools were a crucial aspect of community life for Blacks and Whites, Blacks did form their identity in them. Other institutions, such churches were more crucial. Second, the aspect of politeness and belief in law made the experience in Holly Springs unique to that place, and thus, warrants further study to determine its place within the Civil Rights Movement. Finally, while the political and economic control of Holly Springs remained with Whites, desegregation led to the resegregation of the public schools: as Whites left to private schools. ^

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The Balmis expedition, sent to America by the Spanish monarch Charles IV in 1803, was a watershed in the history of Medicine as it made smallpox vaccination available for the first time, effectively prevented the disease from spreading, and saved thousands of lives. Immunization required complex administrative measures and political decisions including the creation of Vaccination Boards, all of which involved different sectors of Spanish American society. This dissertation argues that at the beginning of the nineteenth century the Spanish American colonial state had reached some level of maturity and cohesion that made it capable of executing this complex project in public health. The significance of this mobilization and the every-day experience in implementing this new public health measure is the center of this work. It is situated geographically in Venezuela and Cuba, entities which took different evolutionary paths in the nineteenth century. The organization and functioning of Vaccination Boards in these two areas are used to illustrate the state formation process, and sharp political differences in this critical period.

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Since the arrival of the first African slaves to Cuba in 1524, the issue of race has had a long-lived presence in the Cuban national discourse. However, despite Cuba’s colonial history, it has often been maintained by some historians that race relations in Cuba were congenial with racism and racial discrimination never existing as deep or widespread in Cuba as in the United States (Cannon, 1983, p. 113). In fact, it has been argued that institutionalized racism was introduced into Cuban society with the first U.S. occupation, during 1898–1902 (Cannon, 1983, p. 113). This study of Cuba investigates the influence of the United States on the development of race relations and racial perceptions in post-independent Cuba, specifically from 1898-1902. These years comprise the time period immediately following the final fight for Cuban Independence, culminating with the Cuban-Spanish-American War and the first U.S. occupation of Cuba. By this time, the Cuban population comprised Africans as well as descendants of Africans, White Spanish people, indigenous Cubans, and offspring of the intermixing of the groups. This research studies whether the United States’ own race relations and racial perceptions influenced the initial conflicting race relations and racial perceptions in early and post-U.S. occupation Cuba. This study uses a collective interpretative framework that incorporates a national level of analysis with a race relations and racial perceptions focus. This framework reaches beyond the traditionally utilized perspectives when interpreting the impact of the United States during and following its intervention in Cuba. Attention is given to the role of the existing social, political climate within the United States as a driving influence of the United States’ involvement with Cuba. This study reveals that emphasis on the role of the United States as critical to the development of Cuba’s race relations and racial perceptions is credible given the extensive involvement of the U.S. in the building of the early Cuban Republic and U.S. structures serving as models for reconstruction. U.S. government formation in Cuba aligned with a governing system reflecting the existing governing codes of the U.S. during that time period.

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This study examined the perceptions of state governmental officials and administrators from the state university system, community college system, and independent institutions concerning the ability of various groups to influence state-level higher education policy formation. The study was conducted in Florida for the period 1989-94. Florida has a history of legislative involvement in higher education, an unique system of state universities and community colleges, and a limited number of private institutions of higher education. This study was grounded in the works of Mortimer and McConnell (1978), Millett (1987), Marshall, Mitchell, and Wirt (1989) and Finitfer, Baldwin, and Thelin (1991). The study represented the application of an embedded, single-case design. A survey was the primary collection instrument. Respondents were asked questions concerning: (a) personal involvement in higher education, (b) perceptions of the ability of various groups to influence higher education policy, (c) the names of particular individuals considered key players in higher education policy formation, (d) important state-level documents, (e) personal knowledge of key areas of policy formation, and (f) emerging higher education issues in Florida. Quantitative and qualitative methods were used to analyze the different sections of the survey. The findings indicated that a power and influence hierarchy exists among the various groups that attempt to influence higher education policy and that this hierarchy is recognized by state government officials and higher education administrators. While an analysis of variance of the various groups revealed a few differences between state government officials and higher education personnel, the high overall agreement was an important finding. Leading members of the legislature, especially the Chair of the Senate Higher Education Committee, and key staff members, especially from the Senate Ways & Means Committee, were considered the most influential. Representatives from higher education institutions and research organizations were considered among the least influential. Emerging issues identified by the respondents included: (a) the political nature of state-level policy formation, (b) the role of legislative staff, (c) the competition for state moneys, (d) legislative concern for state-wide budgetary efficiency, and (e) legislative attempts to define quality and supervise academic program development for higher education.