Projeto interdisciplinar de literatura, filosofia, matemática, ciências e suas tecnologias: IFSOFIA

Trabalho apresentado no 31º SEURS - Seminário de Extensão Universitária da Região Sul, realizado em Florianópolis, SC, no período de 04 a 07 de agosto de 2013 - Universidade Federal de Santa Catarina.O projeto busca fomentar a prática de leitura e reflexões a partir de textos clássicos de Filosofia, Literatura e Matemática. Além disso, uma posterior contribuição ao desenvolvimento dos estudos e da aprendizagem dos envolvidos. Não há dúvidas de que o conhecimento científico é produzido pelas mentes que pensam. Pensam a partir de problemas vivenciados – seja através de situações concretas ou mesmo da interpretação de leituras das mais variadas literaturas. Para tanto, criou-se um grupo de leitura interdisciplinar a fim de se expandir tais atividades imprescindíveis ao domínio da palavra e da escrita. Em outras palavras, não há como despertar a autonomia na aprendizagem teórica de alguém que não sabe ler. A leitura é imprescindível a toda e qualquer atividade de pesquisa exploratória ou mesmo bibliográfica. A própria elaboração do relatório de estágio que os alunos apresentam ao final de seus cursos pressupõe a capacidade de sistematizar a interpretação de uma investigação de determinada pesquisa em suas respectivas áreas do conhecimento. A leitura é um dos fundamentos imprescindíveis não apenas ao desenvolvimento de uma pesquisa, mas também à constituição de um sujeito que queira contribuir com a evolução de uma dada ciência. Aprender é um ato de criação que envolve não apenas raciocínio e imaginação da mente, mas também leitura. A leitura da palavra, de códigos, ou mesmo de diferentes visões de mundo é sinal de que o conhecimento científico vai além de uma mera observação. Ele depende de um raciocínio que opere com hipóteses, experimentações, generalizações, especificações; precisa ir além do meramente observável. A leitura atenta, reflexiva e analítica é um dos momentos essenciais para todo e qualquer avanço cognitivo. Aqui se fundamenta a presente prática interdisciplinar de incentivo a nossos alunos se prepararem para o universo acadêmico da pesquisa, do trabalho, das ciências e suas tecnologias

Are elevation and open-water conversion of salt marshes connected?

Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 47(3), (2020): e2019GL086703, doi:10.1029/2019GL086703.Salt marsh assessments focus on vertical metrics such as accretion or lateral metrics such as open‐water conversion, without exploration of how the dimensions are related. We exploited a novel geospatial data set to explore how elevation is related to the unvegetated‐vegetated marsh ratio (UVVR), a lateral metric, across individual marsh “units” within four estuarine‐marsh systems. We find that elevation scales consistently with the UVVR across systems, with lower elevation units demonstrating more open‐water conversion and higher UVVRs. A normalized elevation‐UVVR relationship converges across systems near the system‐mean elevation and a UVVR of 0.1, a critical threshold identified by prior studies. This indicates that open‐water conversion becomes a dominant lateral instability process at a relatively conservative elevation threshold. We then integrate the UVVR and elevation to yield lifespan estimates, which demonstrate that higher elevation marshes are more resilient to internal deterioration, with an order‐of‐magnitude longer lifespan than predicted for lower elevation marshes.This study was supported by the USGS through the Coastal Marine Hazards/Resources Program, the National Park Service through the Natural Resource Preservation Program, and the U.S. Fish and Wildlife Service through the Science Support Partnership. Erika Lentz, Elizabeth Pendleton, Meagan Gonneea, Joel Carr, and two anonymous reviewers provided constructive advice on the study. S.F. was partly supported by US National Science Foundation award 1637630 (PIE LTER), 1832221 (VCR LTER). The geospatial data used in this study are published in the Coastal Wetlands Synthesis Products catalog on ScienceBase (https://www.sciencebase.gov/catalog/item/5b73325ee4b0f5d5787c5ff3)

Salt marsh erosion rates and boundary features in a shallow Bay

Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Earth Surface 121 (2016): 1861–1875, doi:10.1002/2016JF003975.Herein, we investigate the relationship between wind waves, salt marsh erosion rates, and the planar shape of marsh boundaries by using aerial images and the numerical model Coupled-Ocean-Atmosphere-Wave-Sediment-Transport Modeling System (COAWST). Using Barnegat Bay, New Jersey, as a test site, we found that salt marsh erosion rates maintain a similar trend in time. We also found a significant relationship between salt marsh erosion rates and the shape of marsh boundaries which could be used as a geomorphic indicator of the degradation level of the marsh. Slowly eroding salt marshes are irregularly shaped with fractal dimension higher than rapidly deteriorating marshes. Moreover, for low-wave energy conditions, there is a high probability of isolated and significantly larger than average failures of marsh portions causing a long-tailed distribution of localized erosion rates. Finally, we confirm the existence of a significant relationship between salt marsh erosion rate and wind waves exposure. Results suggest that variations in time in the morphology of salt marsh boundaries could be used to infer changes in frequency and magnitude of external agents.Department of the Interior Hurricane Sandy Recovery program Grant Number: GS2-2D; NSF DEB Grant Number: 0621014; OCE Grant Number: 12382122017-04-2

Stage-discharge relationship in tidal channels

Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here by permission of Association for the Sciences of Limnology and Oceanography for personal use, not for redistribution. The definitive version was published in Limnology and Oceanography: Methods 15 (2017): 394–407, doi:10.1002/lom3.10168.Long-term records of the flow of water through tidal channels are essential to constrain the budgets of sediments and biogeochemical compounds in salt marshes. Statistical models which relate discharge to water level allow the estimation of such records from more easily obtained records of water stage in the channel. Here we compare four different types of stage-discharge models, each of which captures different characteristics of the stage-discharge relationship. We estimate and validate each of these models on a two-month long time series of stage and discharge obtained with an Acoustic Doppler Current Profiler in a salt marsh channel. We find that the best performance is obtained by models that account for the nonlinear and time-varying nature of the stage-discharge relationship. Good performance can also be obtained from a simplified version of these models, which captures nonlinearity and nonstationarity without the complexity of the fully nonlinear or time-varying models.This research was supported by the National Science Foundation (awards OCE1354251, OCE1354494, and OCE1238212).2018-04-2

Effects of sediment disturbance regimes on Spartina seedling establishment: implications for salt marsh creation and restoration

Seedling establishment is an important process relevant for the restoration of salt marsh within the framework of sustainable coastal defense schemes. Recent studies have increasingly highlighted how the short-term (i.e., the day-to-day) sediment dynamics can form major bottlenecks for seedling establishment. Until recently, studies on quantifying the threshold values of such short-term sediment dynamics for marsh seedlings remain rare. As accretion/erosion trends and dynamics may differ greatly under global change, we study the effects of short-term sediment disturbance-regimes on seedling establishment of two globally distributed foundation species: Spartina alterniflora and Spartina anglica. Seedlings with different disturbance-free periods were exposed to a set of different accretion/erosion-regimes in the laboratory. Seedling survival appeared to be much more sensitive to erosion than accretion, seedlings with short disturbance-free periods were more sensitive than seedlings with longer ones, and S. alterniflora was more sensitive than S. anglica. Seedlings were less sensitive to gradual changes in sediment height (accretion/erosion) than to abrupt changes where time for morphological adjustment is lacking. Critical erosion depth (the maximum erosion that seedlings are able to withstand) was shown to mainly depend on sedimentation history. Our results confirm that the establishment of Spartina seedlings requires a flooding disturbance-free “window of opportunity” and that sediment disturbances affect their survival both directly and via morphological adjustment. These results provide fundamental insights into seedling establishment that can be used for designing engineering measures to create suitable conditions and enable marsh creation/restoration for nature goals or as part of coastal defense schemes under global change

Alongshore sediment bypassing as a control on river mouth morphodynamics

Author Posting. © American Geophysical Union, 2016. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Earth Surface 121 (2016): 664–683, doi:10.1002/2015JF003780.River mouths, shoreline locations where fluvial and coastal sediments are partitioned via erosion, trapping, and redistribution, are responsible for the ultimate sedimentary architecture of deltas and, because of their dynamic nature, also pose great management and engineering challenges. To investigate the interaction between fluvial and littoral processes at wave-dominated river mouths, we modeled their morphologic evolution using the coupled hydrodynamic and morphodynamic model Delft3D-SWAN. Model experiments replicate alongshore migration of river mouths, river mouth spit development, and eventual spit breaching, suggesting that these are emergent phenomena that can develop even under constant fluvial and wave conditions. Furthermore, we find that sediment bypassing of a river mouth develops though feedbacks between waves and river mouth morphology, resulting in either continuous bypassing pathways or episodic bar bypassing pathways. Model results demonstrate that waves refracting into the river mouth bar create a zone of low alongshore sediment transport updrift of the river mouth, which reduces sediment bypassing. Sediment bypassing, in turn, controls the river mouth migration rate and the size of the river mouth spit. As a result, an intermediate amount of river discharge maximizes river mouth migration. The fraction of alongshore sediment bypassing can be predicted from the balance between the jet and the wave momentum flux. Quantitative comparisons show a match between our modeled predictions of river mouth bypassing and migration rates observed in natural settings.NSF Grant Number: EAR-09521462016-10-2

O uso de fibrina rica em plaquetas na extração de terceiros molares : uma revisão sistemática

A extração de terceiros molares inferiores é um procedimento frequente, apresentando morbidade pós operatória relacionada à dor, edema e limitação funcional temporária. O presente estudo analisou a influência do uso de fibrina rica em plaquetas (L-PRF) em complicações pós-operatórias - dor, edema, trismo e alveolite, após cirurgia de extração de terceiros molares retidos, por meio de revisão sistemática da literatura. A hipótese é a de que a L-PRF atue como coadjuvante na redução de tais complicações. Estudos encontrados no PubMed, que alcançaram os critérios de elegibilidade (ensaios clínicos randomizados para extração de terceiros molares inferiores com uso de PRF, sem terapia adicional, para avaliação de condições pós-operatórias como dor, edema, trismo e alveolite) foram incluídos nesta revisão. A busca por títulos resultou em 42 artigos, dos quais 5 preencheram os critérios para análise quantitativa. O risco de viés foi avaliado. Os estudos incluíram total de 236 pacientes (472 cirurgias). Os resultados mostram influência na redução de complicações, com redução de dor, trismo e edema. O número reduzido de estudos e pacientes incluídos reduz a força de tais conclusões, no entanto.Extraction of mandibular third molars is a common procedure, presenting postoperative morbidity related to pain, edema and temporary functional limitation. The present study analyzed the influence of the use of platelet-rich fibrin (L-PRF) on postoperative complications - pain, edema, trismus and alveolitis, after extraction of impacted third molars, through systematic literature review. The hypothesis was that L-PRF is an adjunct in reducing such complications. Studies found in PubMed that met the eligibility criteria (randomized clinical trials for lower third molar extraction using PRF without additional therapy to assess postoperative conditions such as pain, edema, trismus and alveolitis) were included in this review. The search for titles resulted in 42 articles, of which 5 met the criteria for quantitative analysis. The risk of bias was assessed. The studies included a total of 236 patients (472 surgeries). The results showed L-PRF influence in the reduction of complications of pain, trismus and edema. The small number of studies and patients included reduces the strength of such findings, however

Interactions between barrier islands and backbarrier marshes affect island system response to sea level rise: Insights from a coupled model

Interactions between backbarrier marshes and barrier islands will likely play an important role in determining how low-lying coastal systems respond to sea level rise and changes in storminess in the future. To assess the role of couplings between marshes and barrier islands under changing conditions, we develop and apply a coupled barrier island-marsh model (GEOMBEST+) to assess the impact of overwash deposition on backbarrier marsh morphology and of marsh morphology on rates of island migration. Our model results suggest that backbarrier marsh width is in a constant state of change until either the backbarrier basin becomes completely filled or backbarrier marsh deposits have completely eroded away. Results also suggest that overwash deposition is an important source of sediment, which allows existing narrow marshes to be maintained in a long-lasting alternate state (similar to 500m wide in the Virginia Barrier Islands) within a range of conditions under which they would otherwise disappear. The existence of a narrow marsh state is supported by observations of backbarrier marshes along the eastern shore of Virginia. Additional results suggest that marshes reduce accommodation in the backbarrier bay, which, in turn, decreases island migration rate. As climate change results in sea level rise, and the increased potential for intense hurricanes resulting in overwash, it is likely that these couplings will become increasingly important in determining future system behavior