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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.
291

A prática coral juvenil transitando em ambientes formais e não formais : perspectivas aplicadas à educação musical /

Daroz, Irandi Fernando. January 2014 (has links)
Orientador: Marisa Trench de Oliveira Fonterrada / Banca: Dorotéa Machado Kerr / Banca: Fábio Miguel / Banca: Rosa Simões / Banca: Leila Rosa Vertamatti / Resumo: Das práticas artísticas coletivas, a música ocupa um papel de destaque, pois ela está presente entre os jovens em termos autobiográficos constituindo-se um poderoso instrumento de comunicação. Este estudo parte da necessidade de entender as culturas juvenis e seus modos de representação, principalmente no que se refere à escuta musical, de modo que esta preocupação possa indicar formas mais atrativas da prática do canto coral com jovens. Destacamos a importância desta prática como possibilidade de resgatar valores humanos quanto à sensibilidade, subjetividade e afetividade em contraposição aos problemas enfrentados atualmente pela sociedade quanto à alienação promovida pela mídia e pela indústria cultural, que muitas vezes ressaltam o que é superficial e passageiro em detrimento de relações mais profundas e permanentes da música como lazer ativo, capaz de promover experiências estéticas importantes, desencadear processos criativos e estimular aspectos de fruição. Para tanto nos reportamos à "Sociosofia" do cotidiano, desvelada nas teorias de José Machado Pais, Michel Maffesoli, Giles Deleuze, Félix Guattari e Mihaly Csikszentmihalyi. Destacamos ainda a prática coral juvenil como instrumento eficaz e acessível à Educação Musical na perspectiva de entender como dar-se-ia a inserção desta atividade em ambiente escolar. Consideramos a importância de centralizar o processo de aprendizagem no conhecimento musical do aluno/cantor para que sejam delineadas estratégias de intervenção que possam expandir essas referências por um processo de ressignificação da memória musical, promovendo diálogo entre as culturas popular e erudita. Nesta perspectiva foi imprescindível caracterizar o trabalho do regente coral transitando em ambientes formais (na escola), não formais ou informais (fora da escola) para identificar particularidades e condutas profissionais ajustadas ... / Abstract: Among the collective artistic practices, music plays an important role because it is present among youth in autobiographical terms constituting a powerful communication tool. This study stems from the need to understand youth cultures and their modes of representation, especially in regard to music listening, so this concern may indicate more attractive forms of the choral singing practice with young people. We stress the importance of this activity as a mean to retrieve human values in what regards the sensibility, subjectivity and affectivity in contrast to the current problems faced by society such as the alienation promoted by media and the cultural industry, which often emphasize what is superficial and the fleeting rather than the deeper and permanent relations of music as a active leisure able to promote relevant ethic-aesthetic experiences, start creative processes and stimulating aspects of fruition. Therefore, we refer to the everyday "Sociosophy" unveiled in the theories of José Machado Pais, Michel Maffesoli, Giles Deleuze, Félix Guattari e Mihaly Csikszentmihalyi. We also highlight the youth choir practice as an effective and accessible tool to music education from the perspective of understanding how to include this activity in the school environment. We consider the importance of centralizing the learning process in the student/singer's musical knowledge in order to outline strategies for intervention that can expand these references by a process of re-signification of the musical memory, promoting a dialogue between the scholarly and popular cultures. In this perspective it was essential to characterize the work of the choir conductor both in formal settings (in school), non-formal or informal (outside of school) to identify characteristics and professional behaviors adjusted to the Brazilian reality, noting that, in most cases, the choir is the only possible access to music literacy / Doutor
292

Comparative Profiling of coral symbiont communities from the Caribbean, Indo-Pacific, and Arabian Seas

Arif, Chatchanit 12 1900 (has links)
Coral reef ecosystems are in rapid decline due to global and local anthropogenic factors. Being among the most diverse ecosystems on Earth, a loss will decrease species diversity, and remove food source for people along the coast. The coral together with its symbionts (i.e. Symbiodinium, bacteria, and other microorganisms) is called the ‘coral holobiont’. The coral host offers its associated symbionts suitable habitats and nutrients, while Symbiodinium and coral-associated bacteria provide the host with photosynthates and vital nutrients. Association of corals with certain types of Symbiodinium and bacteria confer coral stress tolerance, and lack or loss of these symbionts coincides with diseased or bleached corals. However, a detailed understanding of the coral holobiont diversity and structure in regard to diseases and health states or across global scales is missing. This dissertation addressed coral-associated symbiont diversity, specifically of Symbiodinium and bacteria, in various coral species from different geographic locations and different health states. The main aims were (1) to expand the scope of existing technologies, (2) to establish a standardized framework to facilitate comparison of symbiont assemblages over coral species and sites, (3) to assess Symbiodinium diversity in the Arabian Seas, and (4) to elucidate whether coral health states have conserved bacterial footprints. In summary, a next generation sequencing pipeline for Symbiodinium diversity typing of the ITS2 marker is developed and applied to describe Symbiodinium diversity in corals around the Arabian Peninsula. The data show that corals in the Arabian Seas are dominated by a single Symbiodinium type, but harbor a rich variety of types in low abundant. Further, association with different Symbiodinium types is structured according to geographic locations. In addition, the application of 16S rRNA gene microarrays to investigate how differences in microbiome structure relate to differences in health and disease demonstrate that coral species share common microbial footprints in phenotypically similar diseases that are conserved between regional seas. Moreover, corals harbor bacteria that are species-specific and distinct from the diseased microbial footprints. The existence of conserved coral disease microbiomes allows for cataloging diseases based on bacterial assemblage over coral species boundaries and will greatly facilitate future comparative analyses.
293

Standardized short-term bleaching assays resolve differences in coral thermotolerance across microhabitat reef sites

Perna, Gabriela 04 1900 (has links)
Coral bleaching is now the main driver of reef degradation. The common notion is that most corals bleach and suffer mortality at just 1-2°C above their mean summer maximum temperatures, but some species and genotypes resist or recover better than others. Here we conducted a series of 18-hour short-term heat stress assays side-by-side with a long-term heat stress experiment to assess the ability of both approaches to resolve putative differences in coral thermotolerance and provide a measure of in situ reef temperature thresholds. Using a suite of measures (photosynthetic performance, coral whitening, chlorophyll a, host protein, algal symbiont counts, and algal type association), we assessed bleaching sensitivity/resilience of Stylophora pistillata colonies from the exposed and protected sides of a near-shore coral reef in the central Red Sea. As suggested by the differential mortality during a previous bleaching event, coral colonies from the protected site exhibited less impacted physiological performance in comparison to their exposed site counterparts, and these differences were resolved using both experimental setups. Notably, the long-term experiment provided better resolution with regard to the different measures collected, but at the price of portability, cost, and duration of the experiment. Variability in resilience to ocean warming is critical to reef persistence, yet we lack standardized diagnostics to rapidly assess bleaching severity or resilience across different corals and locations. Using a newly developed portable experimental system termed CBASS (the Coral Bleaching Automated Stress System), we demonstrate that mobile, short-term heat stress assays can resolve fine-scale differences in coral thermotolerance across reef sites. Based on our results, photosynthetic efficiency measured by non-invasive PAM fluorometry provides a rapid and representative proxy of coral resilience. Our system holds the potential to be employed for large-scale determination of in situ bleaching temperature thresholds across reef sites and species. Such data can then be used to identify resistant genotypes (and reefs) for downstream experimental examination and to complement existing remote-sensing approaches.
294

Phenotypic and transcriptomic differences between colonies of staghorn coral inhabiting disparate microenvironments – implications for coral restoration

Lesneski, Kathryn C. 04 February 2021 (has links)
In the Caribbean, Acropora cervicornis (staghorn coral) exemplifies the worldwide anthropogenic decline of reef-building corals. From the mid-Pleistocene through the mid-1900s, A. cervicornis was a dominant framework builder, providing complex habitat for reef organisms. Since the 1980s, populations of A. cervicornis have declined by as much as 98%. Despite the overall decline, scattered remnants persist, and some appear to be thriving. As in recent studies on other acroporids, if we can identify variation in traits related to resilience in the remaining A. cervicornis, and understand the genetic basis of such variation, we could better forecast the species’ future response to climate change, and inform ongoing restoration efforts. Here, I compare phenotypic and transcriptomic indicators of resilience in A. cervicornis from two nearby but environmentally-disparate habitats on Turneffe Atoll, Belize: Calabash Caye forereef and Blackbird Caye backreef. Blackbird exhibits significantly higher flow, light, average temperature, and temperature variation. Over four years, I conducted a longitudinal study of 122 tagged coral colonies. Corals from Blackbird and Calabash, which I confirmed to be genetically distinct based upon single nucleotide polymorphisms, exhibited pronounced differences in traits related to resilience including the proportion of healthy tissue, chlorophyll, growth, and wound-healing. By most measures, Blackbird corals displayed superior indicators of resilience. Through a two-year reciprocal transplant study involving 120 corals, I identified substantial environmental plasticity in these traits, e.g., Blackbird corals transplanted to Calabash exhibited higher chlorophyll levels and more rapid wound healing than when grown in Blackbird, exceeding the native Calabash corals. RNA sequencing and assembly of site-specific transcriptomes revealed greater diversity of transcripts and genes from photosynthetic symbionts at Blackbird but greater diversity of bacterial associates at Calabash. Single nucleotide polymorphism (SNP) analyses using RNAseq data determined that corals from the two sites were separate putative populations. Principal components analysis of gene expression in natives and transplants revealed a clear distinction based on site of origin, but also a clear effect of environment. Thousands of differentially expressed genes distinguished the sites, including many genes implicated in heat stress, oxidative stress and UV-light stress. This genetic and phenotypic diversity of remnant staghorn populations on Turneffe represents a potential basis for future re-expansion of this important framework builder through natural or assisted shifts toward resilient populations. / 2023-02-03T00:00:00Z
295

The Need for Permanent Mooring Buoys in  the Gulf of Thailand : A Minor Field Study

Andersson, Maria, Ring, Mikaela January 2013 (has links)
The purpose of this paper is to evaluate the need for permanent mooring buoys at the popular off-shore islands of Pattaya, Thailand. By investigating the ecological, social and economic gains and losses of installing such buoys, the project aims to examine whether such buoys would help support a more sustainable development in the area. In order to fulfil the aims and objectives of the project, a literature study, two different questionnaires, interviews, line intercept transects (LIT) and a boat traffic survey were performed.  The results prove that every dive store operator, 71% of the dive instructors/dive masters and 65% of the tourist divers that took part in the interviews or questionnaires have observed anchor damages in the area. This is supported by the results of the LITs, which, although differing greatly between depths, reveal a top score of 44% damaged corals (of which 20% were apparent anchor damages) at snorkelling depth at site 3. At diving depth the damage indexes were generally lower, revealing a top score of 38% damaged corals at Site 2, but no definite anchor damages. The boat traffic survey showed that 192 boats were active in the area, of which 47 used an anchor, during a 3 hour period a Saturday morning. The results also prove that dive store operators and questionnaire participants generally agree that divers wish to see healthy reefs and great aquatic biodiversity when visiting a dive site. The interviews showed that all dive store operators have a positive attitude towards an installation of mooring buoys in the area, which could protect the local reefs and thereby their own business. 85% of the tourist divers that took part in the questionnaires stated they would be willing to pay extra (where a majority of those with a WTP would be willing to pay 7-13 USD) if they could be guaranteed to see healthy coral reefs and a great diversity in species and 88% stated they would be willing to pay extra (where a majority of those with a WTP would be willing to pay 0.7-1.7 USD)  to support a permanent mooring buoy system.  The interviews and the questionnaires also prove that healthy coral reefs hold a special sentimental value, providing invaluable recreational opportunities to humankind.  Conclusively the results indicate that there is a need for permanent mooring buoys in the area. The ecological, social and economic gains of installing permanent mooring buoys seem to overshadow the cost of installation and maintenance of the buoys, meaning the buoys would most certainly improve the conditions for a more sustainable development in the area.
296

Osmoadjustment in the Coral Holobiont

Röthig, Till 04 1900 (has links)
Coral reefs are under considerable decline. The framework builders in coral reefs are scleractinian corals, which comprise so-called holobionts, consisting of cnidarian host, algal symbionts (genus Symbiodinium), and other associated microbes. Corals are commonly considered stenohaline osmoconformers, possessing limited capability to adjust to salinity changes. However, corals differ in their ability to cope with different salinities. The underlying mechanisms have not yet been addressed. To further understand putative mechanisms involved, I examined coral holobiont osmoregulation conducting a range of experiments on the coral Fungia granulosa. In my research F. granulosa from the Red Sea exhibited pronounced physiological reactions (decreased photosynthesis, cessation of calcification) upon short-term incubations (4 h) to high salinity (55). However, during a 29-day in situ salinity transect experiment, coral holobiont photosynthesis was unimpaired under high salinity (49) indicating acclimatization. F. granulosa microbiome changes after the 29-day high salinity exposure aligned with a bacterial community restructuring that putatively supports the coral salinity acclimatization (osmolyte synthesis, nutrient fixation/cycling). Long-term incubations (7 d) of cultured Symbiodinium exhibited cell growth even at ‘extreme’ salinity levels of 25 and 55. Metabolic profiles of four Symbiodinium strains exposed to increased (55) and decreased (25) salinities for 4 h indicated distinct carbohydrates and amino acids to be putatively involved in the osmoadjustment. Importantly, under high salinity the osmolyte floridoside was consistently increased. This could be corroborated in the coral model Aiptasia and in corals from the Persian/Arabian Gulf, where floridoside was also markedly increased upon short- (15 h) and long-term (>24 months) exposure to high salinity, confirming an important role of floridoside in the osmoadjustment of cnidarian holobionts. This thesis demonstrates osmoacclimatization of F. granulosa and osmoadjustment of cultured Symbiodinium. All three main compartments (i.e. coral host, Symbiodinium, bacteria) seem to contribute to the coral holobionts salinity adjustment. However, the exact mechanisms of coral host and bacteria contribution remain to be determined. Floridoside likely constitutes a conserved osmolyte increasing the salinity resilience of Symbiodinium and also of the cnidarian/coral holobiont. Floridoside further possess’ antioxidative properties, possibly providing a protection from reactive oxygen species formation as a result of salinity stress or/and other environmental stressors.
297

Coral-Associated Bacterial Community Dynamics in Healthy, Bleached, and Disease States

Hadaidi, Ghaida A. 11 1900 (has links)
Coral reefs are the proverbial rainforests of the ocean, but these spectacular structures are under threat from globally rising sea surface temperatures and ocean acidification. The Red Sea and the Persian/Arabian Gulf (PAG) display unusually high sea surface temperatures, and therefore, provide a model for studying environmental change. Corals are so-called holobionts consisting of the coral host, photosynthetic algae (Symbiodiniaceae), along with other microorganisms, such as bacteria, archaea, fungi, and viruses. While the importance of bacteria to coral holobiont functioning is acknowledged, little is known about changes in the microbial communities under natural environmental stressors in the Red Sea and the PAG. Accordingly, I investigated microbial community and mucus differences in bleached, healthy, and diseased corals. Analysis of the composition of mucus-associated microbial communities of bleached and healthy Porites lobata colonies from the Red Sea and the PAG were stable, although some regional differences were present. In a distinct study investigating coral disease, a broad range of corals in the Red Sea were shown to be infected with black band disease (BBD). Investigating the microbial community associated with BBD revealed the presence of the three main indicators for BBD (cyanobacteria, sulfate-reducing bacteria (SRB), and sulfide-oxidizing bacteria (SOB). Last, I investigated the chemical composition (carbohydrates) of the surface mucus layer of a range of Red Sea corals. Given that coral mucus represents a first line of defense, I was interested to examine whether mucus carbohydrate composition would point to a role of adaptation to the extreme environment of the Red Sea. This analysis showed that mucus consists of conserved sugars that are globally conserved. In summary, this thesis characterizes the microbial communities associated with a range of coral species in different health states (bleached, healthy, and diseased). The microbial community patterns I characterized support the notion that bacteria contribute to coral holobiont health and possibly adaptation to extreme environmental conditions in the Red Sea and PAG.
298

Decadal-Scale Changes on Coral Reefs in Quintana Roo, Mexico

Nicholls, Thaddeus Allen 01 December 2008 (has links)
In 1988 data on coral reef community composition were collected from two areas, Akumal and Chemuyil, Quintana Roo, Mexico, ranging from 5-35m depth. These areas were revisited in 2005 and data were collected by the same methods and at the same depths as in 1988. Data from 1988 and 2005 were compared to determine if the coral reefs had undergone significant changes, and what specific changes had occurred. Chi-square analysis determined that community composition data collected in 1988 are significantly different from data collected in 2005 at all sites and depths within the categories of corals, gorgonians, sponges, and macroalgae. Mann-Whitney U analyses were performed on abundance data for coral, gorgonians, sponges, macroalgae, crustose coralline algae, erect coralline algae/calcareous algae, filamentous/multi-species turf algae, and non-living substrate. Results from the Mann-Whitney U analysis varied between sites; however significant trends of increasing macroalgae, crustose coralline algae and filamentous/multi-species turf, and declining non-living substrate were observed at almost all sites. H' biodiversity indices J' evenness values and species number (S) were calculated for all sites over the two time periods, with no discernable trends observed. Increases in crustose coralline algae and filamentous/multi-species turf algae suggest that eutrophication and overfishing may be responsible for the trends observed on the reefs at Akumal and Chemuyil. Anecdotal accounts also suggest that eutrophication from septic water flowing through the highly porous karst limestone of the Yucatan Peninsula may be the largest malefactor causing the observed changes. The increase in filamentous/multi-species turf algae exhibited by the data suggests that eutrophication is predominantly responsible for the alternate states of the reefs. Furthermore, evidences indicative of other forms of stress on the reefs, such as bleaching, scraped or broken coral heads, disease, and sedimentation, were rarely observed.
299

Spatiotemporal Change in the Benthic Community of Southeast Florida

Jones, Nicholas P 10 July 2018 (has links)
High-latitude reefs have been postulated as refugia, centers for resilience or the first areas to undergo re-organization under climate change. The Southeast Florida Reef Tract (SEFRT) is a high-latitude reef system (>25 °N) running parallel to the highly urbanized coastline of southeast Florida. With a benthic community comprised of a mixture of coral reef associated assemblages, the SEFRT is towards the northern limit of stony coral cover due to temperature constraints. This study analyzed spatial variations in benthic cover, spatiotemporal changes in the benthic community and the impact of spatial and temporal fluctuations in temperature on benthic cover on the SEFRT, from 2007-2016. Photographic data from two long term monitoring projects was used to calculate the percent cover of taxonomic assemblages in the benthic community. In situ temperature data and modelled data from HYCOM were used in combination to assess the impact of temperature fluctuations and thermal stress events. Data was split on a latitudinal gradient into six defined ecosystem regions based on biogeographic boundaries and at major port channels. These accounted for any possible range expansion and spatiotemporal variations on the SEFRT. Statistical analysis via generalized linear models (GLM) identified significant changes in the major benthic taxa, stony coral, octocoral, sponges and macroalgae. Ecosystem regions showed strong clustering by their taxonomic composition and this was in part created by temperature variation. Stony coral cover significantly declined on the SEFRT and a concomitant significant increase in macroalgae cover may create a negative feedback loop which hinders recovery. Spatiotemporal variations in benthic cover were found between ecosystem regions and thermal stress events, both hot and cold, had immediate and latent impacts on benthic cover. This has resulted in biotic homogenization on the SEFRT with a retraction of outlier regions towards the mean. Anthropogenically influenced high-latitude reefs are significantly impacted by thermal stress. As oceans continue to warm, populations expand, coastlines continue to develop and pollutants persist, the benefits of potential thermal refugia are negated.
300

Climate change effects on cold-water coral reefs and their associated communities

Gasbarro, Ryan, 0000-0002-1719-7132 January 2023 (has links)
The distribution of biodiversity on the planet faces dramatic spatial reorganization from climate change. This is especially true in the marine realm, where species often live near their physiological limits. Thus, effective conservation agendas for marine biodiversity must be predicated upon robust multi-scenario projections of climate-driven changes in oceanographic conditions. However, much of the theory and empirical work on distributional changes in marine biodiversity comes from shallow-water ecosystems. The deep seafloor (> 200 m) has received comparably little attention despite mounting evidence of the accrual of climatic changes within this largest habitable area of the planet. Here, I present a number of case studies predicting the effects of climate change on the distributions of cold-water coral (CWC) reef habitats and their associated fauna, using both modelling approaches and empirical data collected on multiple oceanographic cruises to the CWC reefs of the southeast USA (SEUS) in 2018-2019. These reefs are persistent features of continental margins (~200 – 4000 m ) around the globe, important biodiversity and biogeochemical cycling hotspots, and sentinels of marine climate change. In Chapter 2, I fit global habitat suitability models (HSMs) using publicly available oceanographic and biogeographic products to predict the occurrence of reef-forming CWC species and the reef habitat they form, testing for taxonomic and regional differences in their ecological niches. I then use an ensemble of global climate model outputs as inputs for ensemble HSMs projecting the distributions of these same taxa to 2100 in a range of climate scenarios, and test for differences in distribution changes across species and bioregions. In Chapter 3, I use higher-resolution regional and global climate products and data from multiple oceanographic cruises to the SEUS to build HSMs for this region; this data collation revealed the largest known, essentially continuous CWC reef province on the planet. The models located pivotal climate refugia primarily at deeper (> 600 m) eastward reef sites – notably including those outside of areas designated to protect coral from bottom-contact fisheries – that may remain suitable to 2100 while shallower sites are projected to experience catastrophic declines. In Chapters 4 and 5 I present community ecological work based from research expeditions to CWC reefs of the SEUS described in Chapter 2. In Chapter 4, I use video imagery and in situ collections of intact seafloor communities to test how the abundance, taxonomic and functional diversity, and community structure of invertebrate communities in hard-substratum ecosystems along the SEUS margin, including CWC reefs and submarine canyons change along biocomplexity (e.g. the percentage of live coral cover), bathymetric, and oceanographic gradients. In Chapter 5, I synthesize invertebrate and fish data from SEUS CWC reefs to fit Bayesian community-level joint HSMs predicting the occurrence and abundance of these faunas as functions of their ecological traits. These models reveal strong distinctions fish and invertebrates in their climate and habitat preferences at CWC reefs, suggesting opposing responses to climate change. Overall, Chapters 3-5 expand upon baseline descriptions of reef habitats and coral-associated fauna in the SEUS, testing for mechanisms driving observed ecological patterns across large environmental gradients. Together, this volume improves our understanding of the ecological drivers of vulnerable marine ecosystem occurrence and biodiversity, augmenting conservation efforts for these critical components of the global ocean. / Biology

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