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Biologia populacional e dieta de Stellifer rastrifer (Jordan, 1889) S. stellifer (Bloch, 1790) e S. brasiliensis (Schultz, 1945) (Perciformes, Sciaenidae) na Enseada de Caraguatabuba (SP) / Population biology and diet of Stellifer rastrifer (Jordan, 1889), S. stellifer (Bloch, 1790) and S. brasiliensis (Schultz, 1945) (Perciformes, Sciaenidae) from Caraguatatuba Bay (SP)Maira Pombo 21 September 2010 (has links)
A fim de colaborar com o conhecimento dos vários aspectos das diferentes populações e suas interações para o manejo e conservação dos recursos naturais, foram analisadas a dinâmica populacional e a dieta de três espécies do gênero Stellifer (Sciaenidae), coletadas de agosto de 2003 a outubro de 2004 em áreas rasas da Enseada de Caraguatatuba, com influência mínima dos rios e estuários da região. Os indivíduos de Stellifer rastrifer (n=3183), S. brasiliensis (n=357) e S. stellifer (n=116) concentraram-se em geral na porção sul da enseada e houve diferença entre o tamanho das três espécies (S. rastrifer > S. stellifer > S. brasiliensis), que apresentaram um padrão de variação do comprimento ao longo do tempo bastante semelhante. Todas se mostraram essencialmente carcinófagas, com variação sazonal dos itens alimentares e alta sobreposição alimentar entre elas. Stellifer rastrifer permitiu uma análise de aspectos reprodutivos e de crescimento. A quantidade de fêmeas com gônadas em maturação e maduras foi muito pequena, bem como os valores do índice gonadossomático foram baixos indicando que a área não seja usada para desova. Os valores estimados para os parâmetros de crescimento (L?=20,9, K=0,37 e Z=2,81) indicam que haja uma segregação espacial entre jovens e adultos e que a taxa de mortalidade encontrada deva incluir em sua composição uma elevada taxa de migração dos jovens para áreas mais profundas, onde se supõe que completem seu desenvolvimento. / Intending to collaborate with some knowledge about ecosystems functioning for its suitable management and the conservation of natural resources, it was analyzed the populational dynamics and diet of three species belonging to the genus Stellifer (Sciaenidae), collected from August 2003 to October 2004, in shallow areas of Caraguatatuba Bay, where there was the least influence as possible of rivers and estuaries placed in the region. Species were Stellifer rastrifer (n=3183), S. brasiliensis (n=357) and S. Stellifer (n=116), wich focused at the southern area of the Bay. Species were significantly different from each other for size (S. rastrifer > S. stellifer > S. brasiliensis), although they have shown a quite similar pattern of length variation over time. They all fed upon basically crustaceans, with marked seasonal variation of food items and high dietary overlap among them. Stellifer rastrifer abundance allowed reproductive aspects analysis and the determination of growth parameters. The number of mature gonads in females was very small and gonadosomatic index values throughout the year were low, thus indicating that it is not a sapwn area. The growth parameters calculated (L?=20.9, K=0.37 and Z=2,81) indicate that there is a spatial segregation by size and that the mortality rate must, therefore, include a high rate of older individuals migration to deeper areas, where it is assumed that they complete their development.
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Geopolitics Versus Globalization: United StatesAydogmus, Muslum 01 January 2008 (has links) (PDF)
This thesis aims to discuss the argument of exhaustion of economic globalization as an American foreign policy principle. This study argues that economic globalization is intended to restore declining American hegemony started in 1970s, but it has eventually given way to the argument of &ldquo / return of the geopolitics&rdquo / . The return of the geopolitics is an imperial, expansionist drive as a new foreign policy imperative for United States. The new developments in the international arena in the post-cold war era and especially after the September 11, 2001 brought the end of the globalization as an American project. Globalization is replaced with geopolitics in the transition period from hegemony to empire in United States foreign policy. Because there are new threats for United States in the twenty-first century such as the rise of new global actors in world politics or international competition for oil resources in the strategic regions of the world. In this framework, this study focuses on the rise of new, alternative &ldquo / great powers&rdquo / (European Union, China etc...).
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Spatial-Temporal Characteristics, Source-Specific Variation and Uncertainty Analysis of Health Risks Associated with Heavy Metals in Road Dust in Beijing, ChinaMen, Cong, Liu, Ruimin, Wang, Qingrui, Miao, Yuexi, Wang, Yifan, Jiao, Lijun, Li, Lin, Cao, Leiping, Shen, Zhenyao, Li, Ying, Crawford-Brown, Douglas 01 June 2021 (has links)
Based on the concentrations of ten heavy metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, Zn, Fe) in 144 road dust samples collected from 36 sites across 4 seasons from 2016 to 2017 in Beijing, this study systematically analyzed the levels and main sources of health risks in terms of their temporal and spatial variations. A combination of receptor models (positive matrix factorization and multilinear engine-2), human health risk assessment models, and Monte Carlo simulations were used to apportion the seasonal variation of the health risks associated with these heavy metals. While non-carcinogenic risks were generally acceptable, Cr and Ni induced cautionary carcinogenic risks (CR) to children (confidence levels was approximately 80% and 95%, respectively). Additionally, fuel combustion posed cautionary CR to children in all seasons, while the level of CR from other sources varied, depending on the seasons. Heavy metal concentrations were the most influential variables for uncertainties, followed by ingestion rate and skin adherence factor. The values and spatial patterns of health risks were influenced by the spatial pattern of risks from each source.
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The role of marine offshore protected areas in protecting large pelagics. Practical case: Cocos Island National Park (Costa Rica) / El papel de las áreas marinas protegidas en alta mar en la protección de grandes pelágicos. Caso práctico: Parque Nacional Isla del Coco (Costa Rica)González-Andrés, Cristina 26 February 2021 (has links)
No description available.
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Spatial-Temporal Patterns of Urban Growth in Shanghai, China: Monitoring, Analysis, and SimulationZhang, Qian January 2009 (has links)
Supporting huge population, megacities are definitely the hot spots of production, consumption, and waste generation. Without careful investment and planning, megacities will be overwhelmed by burgeoning negative impacts on the environment, natural resources, and human health, as well as a host of social and economic issues. The unprecedented combination of economic and population growth since the Reform and Open Policy has led China into transition from a largely rural society to a predominantly urban one. Chinese cities, without question, have not escaped the danger of the series of problems during the rapid progress of urbanization. Therefore, monitoring the spatial-temporal patterns of urban sprawl and their impact on the environment is of critical importance for urban planning and sustainable development, especially in developing Chinese cities such as Shanghai. To date, few studies have focused on the urban trajectories of Shanghai over the past 30 years from a remote sensing perspective. Most of the studies were concentrated on the technical issues of image processing and classification. Moreover, research on spatial metrics has focused on analyzing remote sensing classification results rather than on the use of interpreting, assessing, and verifying urban simulation results. Furthermore, many researches merely focused on baseline projection and very few studies took into consideration urban growth scenarios so far. As yet there have been no reported scenario simulations of future Shanghai growth with several land-use categories within urban areas. The overall objective of this research is to investigate the integration of remote sensing, spatial metrics, and spatial-temporal models in the monitoring, analysis, and simulation of urban growth in Shanghai, China. The specific objectives are to: 1). monitor urban dynamics over time with multi-sensor remote sensing images; 2). quantify spatial-temporal properties of urban growth and representing the urban morphological structures by means of spatial metrics; and 3). simulate the geographic extent, patterns, and detailed catalogs of urban growth under different scenarios using Markov-Cellular Automata (Markov-CA) model to support decision making for a more sustainable Shanghai. Through this study, the combined approach using remotely sensed data with change detection techniques, spatial metrics, and a scenarios-based simulation model proved to be effective to understand, represent, and predict the spatial-temporal dynamics of urban growth. In detail, the segmented-based hierarchy classification and visual interpretation were effective methods to extract urban and industrial land with high-resolution remotely sensed images. Direct change detection using variables derived from tasseled cap transformation was efficient for monitoring impervious surface sprawl. Spatial metrics is a quick and executable way to assessing the impact of urban sprawl on landscape dynamic. Markov-CA model is a useful tool to simulate the scenarios of future urban developments and therefore provides the policy options for sustainable urban planning. The research results of urban trajectories and impervious surface sprawl showed that Shanghai experienced high-speed urban sprawl and the rate of urban expansion, however, was not homogeneous spatially and temporally. The general annual urban expansion speed was 34.8 km2 per year; nevertheless, it reached 80.2 km2 per year recent six years from 2001 to 2007, while it touched the bottom speed around 14.3 km2 per year during 1979-1989. The expanded area in the Puxi region was 5.23 times of its original area while that of Pudong region was 19.94 times of its original area during 1979-2007. The research results of landscape analysis demonstrated that greenbelt becomes fractured while infrastructural and commercial area is more and more aggregated in the central Shanghai area, and satellite images such as SPOT Pan, XS and Landsat TM with 10-30 meter resolution are sufficient for the landscape dynamic research in central Shanghai area. The results of scenarios-based simulation indicated that built-up areas in Shanghai will increase significantly in 2025 and Shanghai will experience less urban sprawl and retain a better environment in 2025 under service-oriented center (SOC) than under baseline (NS) or manufacturing-dominant center (MDC) scenario. If favorable policy for MDC scenario is adopted, however, there will be a lot of manufacturing industries gathering in Shanghai and more agricultural lands will be encroached. The present research focused on the analysis of physical and morphological aspects of urban growth. Urban land-use dynamics are, however, intrinsically linked with socio-economic, political, or demographic drivers. Trying to fill in the missing link between traditional urban geography and urban remote sensing & urban simulation and to improve understanding of the interactions between human and natural aspects in the urban socio-ecosystem is the major focus in the next phase of the Ph.D. research. Keywords: Urban growth, Spatial-temporal pattern, Remote sensing, Spatial metrics, Scenarios-based simulation, Shanghai / QC 20110224
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Semiparametric Varying Coefficient Models for Matched Case-Crossover StudiesOrtega Villa, Ana Maria 23 November 2015 (has links)
Semiparametric modeling is a combination of the parametric and nonparametric models in which some functions follow a known form and some others follow an unknown form. In this dissertation we made contributions to semiparametric modeling for matched case-crossover data.
In matched case-crossover studies, it is generally accepted that the covariates on which a case and associated controls are matched cannot exert a confounding effect on independent predictors included in the conditional logistic regression model. Any stratum effect is removed by the conditioning on the fixed number of sets of the case and controls in the stratum. However, some matching covariates such as time, and/or spatial location often play an important role as an effect modification. Failure to include them makes incorrect statistical estimation, prediction and inference. Hence in this dissertation, we propose several approaches that will allow the inclusion of time and spatial location as well as other effect modifications such as heterogeneous subpopulations among the data.
To address modification due to time, three methods are developed: the first is a parametric approach, the second is a semiparametric penalized approach and the third is a semiparametric Bayesian approach. We demonstrate the advantage of the one stage semiparametric approaches using both a simulation study and an epidemiological example of a 1-4 bi-directional case-crossover study of childhood aseptic meningitis with drinking water turbidity.
To address modifications due to time and spatial location, two methods are developed: the first one is a semiparametric spatial-temporal varying coefficient model for a small number of locations. The second method is a semiparametric spatial-temporal varying coefficient model, and is appropriate when the number of locations among the subjects is medium to large. We demonstrate the accuracy of these approaches by using simulation studies, and when appropriate, an epidemiological example of a 1-4 bi-directional case-crossover study.
Finally, to explore further effect modifications by heterogeneous subpopulations among strata we propose a nonparametric Bayesian approach constructed with Dirichlet process priors, which clusters subpopulations and assesses heterogeneity. We demonstrate the accuracy of our approach using a simulation study, as well a an example of a 1-4 bi-directional case-crossover study. / Ph. D.
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Variation in recruitment rates of rocky shore intertidal invertebrates in response to alterations in physical forcings, chlorophyll-a concentration and temperature: the effect of cold fronts / Variação nas taxas de recrutamento de invertebrados do entremarés de costas rochosas em resposta a alterações nas forçantes físicas, concentração de clorofila-a e temperatura: o efeito das frentes friasMazzuco, Ana Carolina de Azevedo 14 December 2015 (has links)
Marine communities are affected by oceanographic processes, which influence ecological interactions, such as recruitment rates, that are essential regulators of community dynamics. These relationships are not constant; they change in space and time or among taxa. We defend the thesis that oceanographic processes of climatic origin influencing larval abundance at the study region, regulate and establish the trends in settlement and recruitment of invertebrates (cirripeds and bivalves) at rocky shore intertidal. We first investigated the recruitment at different temporal scales and its relationships with physical forcings, chlorophyll-a concentration and sea surface temperature. Second, we focused on the spatial synchrony and contrasts of recruitment, and interspecific trends. Third, we described and evaluated the co-variation between cold fronts and the larval abundance and settlement. We concluded that there is a high degree of correlation between recruitment/settlement and the variation of the wind field, which set temporal trends. Cold fronts are important regulators of settlement, but higher recruitment was associated to NE-E winds. Barnacle recruitment is more susceptible to the environmental variations compared to bivalves. Regional recruitment is not spatially synchronic with differences in the scale of 100 km. This study highlights the importance of oceanic-climatic phenomena as predictors of spatio-temporal trends of recruitment showing that climatic fluctuations might have contrasting effects on rocky shore communities. / As comunidades marinhas são afetadas por processos oceanográficos que influenciam as interações ecológicas, como as taxas de recrutamento, reguladores essenciais da dinâmica dessas comunidades. Essas relações não são constantes, elas mudam no espaço e no tempo, ou entre taxa. Aqui nós defendemos a tese que processos oceanográficos de origem climática, por influenciarem a abundância larval região de estudo, regulam e estabelecem tendências do assentamento e recrutamento de invertebrados (cirripedes e bivalves) do entremarés de costas rochosas. Primeiramente, nós investigamos o recrutamento em diferentes escalas de tempo e sua relação com forçantes físicas, concentração de clorofila-a e temperatura da superfície do mar. Em um segundo momento, nós focamos na sincronia e nos contrastes espaciais do recrutamento, e as tendências inter-específicas. Por fim, descrevemos e avaliamos a co-variância entre frentes frias, abundância larval e assentamento. Concluímos que há um alto grau de correlação entre recrutamento/ assentamento e a variação do campo de ventos, o qual estabelece as tendências temporais. As frentes frias são reguladores importantes do assentamento, mas o recrutamento mais alto está associado a ventos de NE-E. O recrutamento de cirripedes é mais susceptível às variações ambientais se comparado aos bivalves. O recrutamento regional não é sincrônico no espaço, com diferenças na escala de 100km. Este estudo destaca a importância dos fenômenos oceano-climáticos na previsão de tendências espaço-temporais do recrutamento, mostrando que flutuações climáticas podem ter efeitos contrastantes nas comunidades de costas rochosas.
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Variation in recruitment rates of rocky shore intertidal invertebrates in response to alterations in physical forcings, chlorophyll-a concentration and temperature: the effect of cold fronts / Variação nas taxas de recrutamento de invertebrados do entremarés de costas rochosas em resposta a alterações nas forçantes físicas, concentração de clorofila-a e temperatura: o efeito das frentes friasAna Carolina de Azevedo Mazzuco 14 December 2015 (has links)
Marine communities are affected by oceanographic processes, which influence ecological interactions, such as recruitment rates, that are essential regulators of community dynamics. These relationships are not constant; they change in space and time or among taxa. We defend the thesis that oceanographic processes of climatic origin influencing larval abundance at the study region, regulate and establish the trends in settlement and recruitment of invertebrates (cirripeds and bivalves) at rocky shore intertidal. We first investigated the recruitment at different temporal scales and its relationships with physical forcings, chlorophyll-a concentration and sea surface temperature. Second, we focused on the spatial synchrony and contrasts of recruitment, and interspecific trends. Third, we described and evaluated the co-variation between cold fronts and the larval abundance and settlement. We concluded that there is a high degree of correlation between recruitment/settlement and the variation of the wind field, which set temporal trends. Cold fronts are important regulators of settlement, but higher recruitment was associated to NE-E winds. Barnacle recruitment is more susceptible to the environmental variations compared to bivalves. Regional recruitment is not spatially synchronic with differences in the scale of 100 km. This study highlights the importance of oceanic-climatic phenomena as predictors of spatio-temporal trends of recruitment showing that climatic fluctuations might have contrasting effects on rocky shore communities. / As comunidades marinhas são afetadas por processos oceanográficos que influenciam as interações ecológicas, como as taxas de recrutamento, reguladores essenciais da dinâmica dessas comunidades. Essas relações não são constantes, elas mudam no espaço e no tempo, ou entre taxa. Aqui nós defendemos a tese que processos oceanográficos de origem climática, por influenciarem a abundância larval região de estudo, regulam e estabelecem tendências do assentamento e recrutamento de invertebrados (cirripedes e bivalves) do entremarés de costas rochosas. Primeiramente, nós investigamos o recrutamento em diferentes escalas de tempo e sua relação com forçantes físicas, concentração de clorofila-a e temperatura da superfície do mar. Em um segundo momento, nós focamos na sincronia e nos contrastes espaciais do recrutamento, e as tendências inter-específicas. Por fim, descrevemos e avaliamos a co-variância entre frentes frias, abundância larval e assentamento. Concluímos que há um alto grau de correlação entre recrutamento/ assentamento e a variação do campo de ventos, o qual estabelece as tendências temporais. As frentes frias são reguladores importantes do assentamento, mas o recrutamento mais alto está associado a ventos de NE-E. O recrutamento de cirripedes é mais susceptível às variações ambientais se comparado aos bivalves. O recrutamento regional não é sincrônico no espaço, com diferenças na escala de 100km. Este estudo destaca a importância dos fenômenos oceano-climáticos na previsão de tendências espaço-temporais do recrutamento, mostrando que flutuações climáticas podem ter efeitos contrastantes nas comunidades de costas rochosas.
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Traffic data sampling for air pollution estimation at different urban scales / Échantillonnage des données de trafic pour l’estimation de la pollution atmosphérique aux différentes échelles urbainesSchiper, Nicole 09 October 2017 (has links)
La circulation routière est une source majeure de pollution atmosphérique dans les zones urbaines. Les décideurs insistent pour qu’on leur propose de nouvelles solutions, y compris de nouvelles stratégies de management qui pourraient directement faire baisser les émissions de polluants. Pour évaluer les performances de ces stratégies, le calcul des émissions de pollution devrait tenir compte de la dynamique spatiale et temporelle du trafic. L’utilisation de capteurs traditionnels sur route (par exemple, capteurs inductifs ou boucles de comptage) pour collecter des données en temps réel est nécessaire mais pas suffisante en raison de leur coût de mise en oeuvre très élevé. Le fait que de telles technologies, pour des raisons pratiques, ne fournissent que des informations locales est un inconvénient. Certaines méthodes devraient ensuite être appliquées pour étendre cette information locale à une grande échelle. Ces méthodes souffrent actuellement des limites suivantes : (i) la relation entre les données manquantes et la précision de l’estimation ne peut être facilement déterminée et (ii) les calculs à grande échelle sont énormément coûteux, principalement lorsque les phénomènes de congestion sont considérés. Compte tenu d’une simulation microscopique du trafic couplée à un modèle d’émission, une approche innovante de ce problème est mise en oeuvre. Elle consiste à appliquer des techniques de sélection statistique qui permettent d’identifier les emplacements les plus pertinents pour estimer les émissions des véhicules du réseau à différentes échelles spatiales et temporelles. Ce travail explore l’utilisation de méthodes statistiques intelligentes et naïves, comme outil pour sélectionner l’information la plus pertinente sur le trafic et les émissions sur un réseau afin de déterminer les valeurs totales à plusieurs échelles. Ce travail met également en évidence quelques précautions à prendre en compte quand on calcul les émissions à large échelle à partir des données trafic et d’un modèle d’émission. L’utilisation des facteurs d’émission COPERT IV à différentes échelles spatio-temporelles induit un biais en fonction des conditions de circulation par rapport à l’échelle d’origine (cycles de conduite). Ce biais observé sur nos simulations a été quantifié en fonction des indicateurs de trafic (vitesse moyenne). Il a également été démontré qu’il avait une double origine : la convexité des fonctions d’émission et la covariance des variables de trafic. / Road traffic is a major source of air pollution in urban areas. Policy makers are pushing for different solutions including new traffic management strategies that can directly lower pollutants emissions. To assess the performances of such strategies, the calculation of pollution emission should consider spatial and temporal dynamic of the traffic. The use of traditional on-road sensors (e.g. inductive sensors) for collecting real-time data is necessary but not sufficient because of their expensive cost of implementation. It is also a disadvantage that such technologies, for practical reasons, only provide local information. Some methods should then be applied to expand this local information to large spatial extent. These methods currently suffer from the following limitations: (i) the relationship between missing data and the estimation accuracy, both cannot be easily determined and (ii) the calculations on large area is computationally expensive in particular when time evolution is considered. Given a dynamic traffic simulation coupled with an emission model, a novel approach to this problem is taken by applying selection techniques that can identify the most relevant locations to estimate the network vehicle emissions in various spatial and temporal scales. This work explores the use of different statistical methods both naïve and smart, as tools for selecting the most relevant traffic and emission information on a network to determine the total values at any scale. This work also highlights some cautions when such traffic-emission coupled method is used to quantify emissions due the traffic. Using the COPERT IV emission functions at various spatial-temporal scales induces a bias depending on traffic conditions, in comparison to the original scale (driving cycles). This bias observed in our simulations, has been quantified in function of traffic indicators (mean speed). It also has been demonstrated to have a double origin: the emission functions’ convexity and the traffic variables covariance.
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Inversion of Nonlinear Dispersive Wave and its Application in Determining Tsunami Wave SoureLi, Lieh-Yu 13 April 2011 (has links)
In this study, the method of deciding the water level of the initial tsunami is proposed by using spatial-temporal focusing (Coalescence) theory and waveform inversion reciprocal with Green function. Tsunami and earthquake are so closely bonded that the current tsunami numerical model is dependent on the parameters of the fault and the initial tsunami water level by calculating the theory of
half flexibility. But in fact, it is not easy to have the parameters of seabed fault so that the initial tsunami water level is very hard to get a accurate value. On the other hand, although the parameters of fault can be speculated by seismic waves, because ground is uneven medium, therefore, it is still a lot of improvement to get the parameters of fault by using seismic waves. For the tsunami simulation, if you have the value of the initial tsunami water level, the fault parameters can be estimated.Since the propagation of tsunami in the ocean is a linear behavior, the propagating process is affected by the topography of the ocean and the nonlinear effect
so minimal that it is to satisfy the linear shallow water equations and the requirement of reversibility;However, in fact, the values of the water level measured by the tide stations on the coast are influenced by the shoaling effect so that the reversibility of linear system can not be directly applied to Coastal areas.Therefore, the overall Inversion procedure on this study consists of two parts; the first one is that the usage of variable
coefficient Korteweg-de Vries (vKdV) equation and the Coalescence theory inverses the data gathered by the Coastal tide stations to the water level data where the depth is more than 50m on the linear region, and compares the above results with the stimulation and confirms the accuracy of the inversed waveform;The second one is that according to the reversibility of the linear system the use of least squares and least squares QR- decomposition (LSQR) method reproduce the initial tsunami wave source that compares with the initial tsunami wave source by stimulating and has a very good conformity. The seismic parameters can be easily decided by the above results.
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