Orientadores: Fernando Roberto Martins, Roque Cielo Filho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T23:27:14Z (GMT). No. of bitstreams: 1 Eisenlohr_PedroVasconcellos_D.pdf: 5031801 bytes, checksum: e52fd0b20ded59b879aa03884e6f9b19 (MD5) Previous issue date: 2012 / Resumo: Na América do Sul, há pouco conhecimento sobre as relações florísticas entre Domínios de florestas e savanas. Considerando os Domínios do Cerrado e Amazônico no Brasil e a área de transição entre eles, investigamos os padrões de similaridade e de gradientes (Capítulo 1), de diversidade alfa (Capítulo 2) e de distribuição geográfica potencial (Capítulo 3) da flora arbórea e suas correlações com variáveis ambientais e estruturas espaciais. Aplicamos análises multivariadas, estimativas de diversidade de espécies, modelos lineares gerais e ferramentas espaciais, incluindo análise de autocorrelação espacial e modelagem de distribuição geográfica de espécies, sobre dados florísticos e ambientais em um banco de dados constituído por 90 levantamentos. No Capítulo 1, encontramos que a conexão entre os Domínios ocorre como um gradiente fortemente correlacionado com a precipitação anual, opondo climas pluviais (Domínio Amazônico) a climas continentais (Domínio do Cerrado). As florestas de várzea amazônicas constituem um bloco florístico isolado e a grande área de Transição mostra afinidade florística a ambos os Domínios. A flora tem forte padrão espacial: autocorrelaciona-se positivamente a curtas distâncias e negativamente a grandes distâncias, indicando diminuição da similaridade com o aumento da distância geográfica. O diâmetro do tronco do menor indivíduo incluído na amostra (DMI) também foi uma variável importante para explicar a variação florística. No Capítulo 2, a diversidade alfa correlacionou-se significativamente com variáveis de precipitação e de temperatura, mostrou-se influenciada pelo espaço e apresentou correlação significativa com o DMI. Alguns resultados dos modelos globais foram aparentemente contraditórios com a literatura e decorrem, pelo menos em parte, de variações locais. No Capítulo 3, detectamos que espécies do Cerrado, influenciadas primariamente pela sazonalidade de precipitação, seriam encontradas principalmente na Floresta Semidecídua Atlântica, no sudeste do Brasil, e espécies amazônicas, influenciadas predominantemente por variáveis térmicas, seriam encontradas em outras florestas pluviais do norte e noroeste da América do Sul e em algumas áreas sazonalmente secas, inclusive no Brasil Central, onde predomina o Domínio do Cerrado. As principais conclusões desta Tese foram: 1) A flora arbórea desses Domínios e da transição apresenta forte padrão espacial, que segue um gradiente linear em grande escala separando parte considerável das floras dos dois Domínios. 2) A variação de diversidade alfa não foi significativa entre os Domínios e a Transição, indicando que transições em larga escala não necessariamente representam áreas de maior diversidade que os Domínios adjacentes. 3) Além das variáveis geoclimáticas, o diâmetro do menor indivíduo incluído na amostra também foi um importante preditor dos padrões de similaridade e diversidade alfa ao longo da área de estudo, mas o mesmo não ocorreu com o número de indivíduos amostrados. 4) Conforme alguns autores já haviam indicado, é possível encontrar elevada performance de modelos de distribuição potencial mesmo para espécies com número relativamente baixo de registros (<25). 5) A adequabilidade climática de espécies amazônicas em parte do Domínio do Cerrado suporta a hipótese de expansão da Floresta Amazônica, que ocorreria desde o Pleistoceno e acompanharia as flutuações climáticas de períodos secos e frios a períodos quentes e úmidos / Abstract: In South America, little is known about the floristic links between forests and savannas domains. Considering the Cerrado and Amazonian Domains in Brazil and the transition area between them, we investigated the patterns of similarity and gradients (Chapter 1), alpha diversity (Chapter 2) and potential geographical distribution (Chapter 3) of the tree flora and its correlations with environmental variables and spatial structures. We applied multivariate analysis, estimates of species diversity, general linear models and spatial tools, including spatial autocorrelation analysis and modeling of species geographic distribution, on floristic and environmental data in a database consisting of 90 surveys. In Chapter 1, we found that the connection between the Domains occurs as a gradient strongly correlated with the annual precipitation, opposing pluvial (Amazonian Domain) to continental climates (Cerrado Domain). Amazonian floodplain forests constitute an isolated block and the large transition zone presents floristic affinities with both Domains. The flora has a strong spatial pattern, positively autocorrelated over short distances and negative autocorrelated at large distances, indicating decreasing similarity with increasing geographic distance. The trunk diameter of the smallest individual sampled (DSI) was also an important variable to explain the floristic variations. In Chapter 2, the alpha diversity correlated significantly with precipitation and temperature variables, was influenced by the space and showed significant correlation with DSI. Some results of global models were apparently contradictory to the literature and result from local variations, at least in part. In Chapter 3, we detected that Cerrado' species, primarily influenced by the precipitation seasonality, would be found mainly in the Atlantic Semideciduous Forest in southeastern Brazil, and amazonian species, influenced predominantly by thermal variables, would be found in other rain forests of the north and northwest of South America and in some seasonally dry areas, including Central Brazil, where Cerrado Domain predominates. The main conclusions of this thesis were: 1) The tree flora of these Domains and the transition has a strong spatial pattern, which follows a large-scale linear gradient separating considerable proportion of the flora of both Domains. 2) The variation in alpha diversity was not significant between both Domains and Transition, indicating that large-scale transitions do not necessarily represent more diverse areas than the adjacent Domains. 3) Besides the geoclimatic variables, the diameter of the smallest individual sampled was also an important predictor of similarity and alpha diversity patterns along the study area - this did not occur with the number of individuals sampled. 4) According to some authors have stated, it is possible to find high-performance models of potential distribution even for species with relatively low number of records (<25). 5) The climatic suitability of Amazonian species in part of the Cerrado Domain supports the hypothesis of expansion of the Amazonian Rainforest, which would occur since the Pleistocene climatic fluctuations and accompany dry and cold periods to hot and humid ones / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal

No description available.

Orientador: Flavio Antonio Maes dos Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-07T23:32:15Z (GMT). No. of bitstreams: 1 Costa_RafaelCarvalhoda_M.pdf: 1027231 bytes, checksum: c931924474731a019f3be441174bbcb0 (MD5) Previous issue date: 2006 / Resumo: O domínio dos cerrados compreende uma grande variação de tipos vegetacionais, com fisionomias indo de campestres a florestais. Estas diferenças estão relacionadas a vários fatores ecológicos que podem ter influência em aspectos de populações vegetais como relações alométricas e padrão espacial. Comparações desses aspectos entre espécies são importantes na distinção entre diferentes estratégias de espécies do cerrado que as permitam ocupar tipos diferentes de habitats. Nesse sentido, este estudo analisou variações em 1) relações alométricas entre altura e diâmetro e 2) padrão espacial de espécies de Vochysiaceae, em fragmentos de cerrado de diferentes fisionomias. As espécies comparadas entre fragmentos, Qualea grandiflora Mart. e Vochysia tucanorum Mart, diferiram em plasticidade da relação entre altura e diâmetro entre fragmentos: Q. grandiflora apresentou diferenças de forma e V. tucanorum diferenças de tamanho. A variação de Q. grandiflora parece não ser resposta ao estresse causado pelo vento, pois as diferenças encontradas não corresponderam às ocorrências dos indivíduos em fisionomias abertas ou fechadas. As variações de V. tucanorum sugerem um efeito do estresse causado pelo vento, mas não foram possíveis comparações independentes dos fatores fogo e vento entre fragmentos. Comparações de espécies de Vochysiaceae com uma espécie externa ao grupo, no mesmo fragmento, indicam tendência filogenética da variação de forma no nível genérico (Qualea x Vochysia). Por outro lado, semelhanças entre Q. grandiflora e Eriotheca gracilipes (K.Schum.) A.Robyns indicam convergência relacionada à ação de fatores ecológicos, como distúrbios, por exemplo.Quanto aos padrões espaciais, Q. grandiflora e V. tucanorum diferiram nas escalas estudadas: entre e no interior de fragmentos. Na escala ampla, os padrões parecem consistentes com informações da literatura sobre o habitat preferencial das espécies. Na escala restrita, os padrões de classes de tamanho sugerem diferenças entre as espécies nos processos determinantes dos padrões espaciais. Q. grandiflora, cujos padrões foram aleatórios na menor classe de tamanho e passaram a agregados nas demais, teria padrões determinados por condições específicas ao estabelecimento de indivíduos em classes de tamanho maiores. Tais condições estariam estruturadas no espaço. V.tucanorum teve uma diminuição de agregação nas classes maiores indicando a ação de algum fator de mortalidade dependente de densidade. Os resultados indicam diferenças importantes entre as espécies de cerrado estudadas no que diz respeito à plasticidade de forma e padrão espacial, tais resultados podem representar tendências para espécies arbóreas do cerrado de uma maneira geral. No entanto, estudos com um número maior de espécies incluindo um número maior de fisionomias são necessários para propor generalizações mais seguras / Abstract: The Brazilian savannas, known as cerrado, comprises a wide range of physiognomies, from grasslands to forests. This physiognomic variation is probably related to changes in a number of ecological factors that can influence features of plant populations as plant form and spatial pattern. Comparisons among species are important to identify distinct strategies that enable cerrado plants to occupy different kinds of habitats. Following this approach, this study compared height x diameter allometric relationship and spatial pattern among populations of cerrado tree species of Vochysiaceae in fragments of different physiognomies. The relationship between height and diameter of two studied species was compared among fragments. Qualea grandiflora Mart. and Vochysia tucanorum Mart. shown different trends, the first had variable allometric coefficients and the second had differences only in allometric constants. For Q. grandiflora, variation of allometric coefficients does not seem to be related to wind stress since the estimated parameters do not correspond to differences between closed and open physiognomies. Variation of allometric constants for V. tucanorum suggests differences related to wind stress but we weren¿t able to make independent comparisons of open x closed and fire x protected fragments for this species. We compared the allometries of close and distant related sympatric species searching evidence for a phylogenetic effect. We found differences among Vochysia x Qualea as evidence for such effect. However, we have not found statistical differences among Q. grandiflora and Eriotheca gracilipes (K.Schum.) A.Robyns, a species used as a taxonomic control. This finding evinces form convergence among cerrado tree species, probably due to ecological factors like disturbance. Q. grandiflora and V. tucanorum also differed when compared in a two-scale spatial pattern study considering four cerrado fragments with different physiognomies. The species¿ differences in large scale (considering density patterns among fragments) were consistent with literature information on preferential habitat of each one. V. tucanorum was more aggregated than Q. grandiflora being restricted to a fire protected fragment of closed physiognomy. In local scale (spatial patterns of five soil level diameter classes-SLD in plots of 50 x 200 m), differences among species were they co-occurred suggest distinct process acting upon different stages of plant development structuring their populations. The first size class (SLD < 5cm) of Q. grandiflora had a change from random spatial pattern to aggregated in larger SLD classes. A space-structured factor can be responsible for higher recruitment chances only in certain places promoting the observed change from random to aggregated pattern in larger SLD classes of Q. grandiflora. V. tucanorum had a change from aggregated to random pattern with SLD class what can be a consequence of density dependent process related to competition or natural enemies. Our findings points out to the importance of differences among cerrado tree species concerning plant form and spatial pattern. However, studies including more species and cerrado physiognomies are required to make generalizations concerning the trends found here / Mestrado / Mestre em Ecologia

No description available.

Agricultural soil properties exhibit variation over field plot scales that can ultimately effect the yield. This study performs multiple spatial pattern analyses in order to design spatially dependent regression models to better understand the interaction between these soil properties. The Cation Exchange Capacity (CEC) and Calcium-Magnesium Ratio (CaMgR) are analyzed with respect to Calcium, Magnesium, and soil moisture values. The CEC and CaMgR are then used to determine impact on the yield values present for the field. Results of this study show a significant measure of model parsimony (0.979) for the Geographically Weighted Regression (GWR) model of the CEC with free Ca, Mg, and soil moisture as explanatory variables. The model for CaMgR using the same explanatory variables has a much lower measure of model fit. The yield model using the CEC and CaMgR as explanatory variables is also low, which is representative of the underlying processes also impacting yield.

When analyzing complex scenes, humans often focus their attention on an object at a particular spatial location in the presence of background noises and irrelevant visual objects. The ability to decode the attended spatial location would facilitate brain computer interfaces (BCI) for complex scene analysis. Here, we tested two different neuroimaging technologies and investigated their capability to decode audio-visual spatial attention in the presence of competing stimuli from multiple locations. For functional near-infrared spectroscopy (fNIRS), we targeted dorsal frontoparietal network including frontal eye field (FEF) and intra-parietal sulcus (IPS) as well as superior temporal gyrus/planum temporal (STG/PT). They all were shown in previous functional magnetic resonance imaging (fMRI) studies to be activated by auditory, visual, or audio-visual spatial tasks. We found that fNIRS provides robust decoding of attended spatial locations for most participants and correlates with behavioral performance. Moreover, we found that FEF makes a large contribution to decoding performance. Surprisingly, the performance was significantly above chance level 1s after cue onset, which is well before the peak of the fNIRS response. For electroencephalography (EEG), while there are several successful EEG-based algorithms, to date, all of them focused exclusively on auditory modality where eye-related artifacts are minimized or controlled. Successful integration into a more ecological typical usage requires careful consideration for eye-related artifacts which are inevitable. We showed that fast and reliable decoding can be done with or without ocular-removal algorithm. Our results show that EEG and fNIRS are promising platforms for compact, wearable technologies that could be applied to decode attended spatial location and reveal contributions of specific brain regions during complex scene analysis.

A regional IPM project was initiated with four rounds of sampling for white grubs on the fairways of nine golf courses located on the Lower Peninsula of eastern Virginia, from 2000 through 2002. Fifteen regressor variables were collected and measured that included local-scale variables, golf course management practices and spatial pattern metrics derived from satellite images that underwent two methods of a supervised classification of six land-cover types (turf, woods, wetland, urban, bare soil and water) on four landscape scales derived from 10 km x 10 km buffer zones surrounding each golf course. Pearson's correlation coefficients were calculated to reduce the number of variables to a few that were highly correlated with white grub densities. Mallow's C(p) calculations were performed on the reduced variable sets to extract those that would be highly predictive. A multiple linear regression was performed using the Mallow's variables to develop eight regression equations (two classification methods x four landscape scales) that were used to predict regional white grub presence and abundance in 2003 on six additional golf courses located on the Lower Peninsula. The best model was the 6 km x 6 km buffer zones model from the second classification method, which included one local-scale variable (golf course age) and three spatial pattern metrics (total turf area, total turf area-to-total urban area ratio, and a woods interspersion-juxtaposition index). The mean difference between actual and predicted values was -0.15, standard deviation = 0.79, R2 = 81.38%. Additionally, a study was conducted to determine whether the number of white grubs collected from transects of sampled golf course fairways was significantly different from those found in the roughs. White grub counts from the roughs were significantly higher (mean = 0.283 grubs/transect, standard error = 0.0135) than those from fairways (mean = 0.146 grubs/transect, standard error = 0.0188); t = -4.31, df = 735, P = 0.0001. / Ph. D.

Les interfaces cerveau-ordinateur (ou BCI en anglais pour Brain-Computer Interfaces) mettent en place depuis le système nerveux central un circuit artificiel secondaire qui remplace l’utilisation des nerfs périphériques, permettant entre autres à des personnes ayant une déficience motrice grave d’interagir, uniquement à l’aide de leur activité cérébrale, avec différents types d’applications, tels qu’un système d’écriture, une neuro-prothèse, un fauteuil roulant motorisé ou un bras robotique. Une technique répandue au sein des BCI pour enregistrer l’activité cérébrale est l’électroencéphalographie (EEG), étant donné que contrairement à d’autres techniques d’imagerie, elle est non invasif et peu coûteuse. En outre, l’imagination motrice (MI), c’est-à-dire les oscillations des neurones du cortex moteur générées lorsque les sujets imaginent effectuer un mouvement sans réellement l’accomplir, est appropriée car détectable dans l’EEG et liée à l’activité motrice pour concevoir des interfaces comme des neuro-prothèses non assujetties à des stimuli. Cependant, même si des progrès importants ont été réalisés au cours des dernières années, un contrôle 3D complet reste un objectif à atteindre. Afin d’explorer de nouvelles solutions pour surmonter les limitations existantes, nous présentons une approche multiclasses qui considère la détection des imaginations motrices combinées. Le paradigme proposé comprend l’utilisation de la main gauche, de la main droite, et des deux pieds ensemble. Ainsi, par combinaison, huit commandes peuvent être fournies pour diriger un bras robotisé comprenant quatorze mouvements différents qui offrent un contrôle 3D complet. À cette fin, un système de commutation entre trois modes (déplacement du bras, du poignet ou des doigts) a été conçu et permet de gérer les différentes actions en utilisant une même commande. Ce système a été mis en oeuvre sur la plate-forme OpenViBE. En outre, pour l’extraction de caractéristiques une nouvelle approche de traitement d’information fournie par les capteurs a été développée sur la base de l’emplacement spécifique des sources d’activité liées aux parties du corps considérées. Cette approche permet de regrouper au sein d’une seule classe les différentes actions pour lesquelles le même membre est engagé, d’une manière que la tâche multiclasses originale se transforme en un problème équivalent impliquant une série de modèles de classification binaires. Cette approche permet d’utiliser l’algorithme de Common Spatial pattern (CSP) dont la capacité à discriminer des rythmes sensorimoteurs a été largement montrée mais qui présente l’inconvénient d’être applicable uniquement pour différencier deux classes. Nous avons donc également contribué à une nouvelle stratégie qui combine un ensemble de CSP et la géométrie riemannienne. Ainsi des caractéristiques plus discriminantes peuvent être obtenues comme les distances séparant les données des centres des classes considérées. Ces stratégies ont été appliquées sur trois nouvelles approches de classification qui ont été comparées à des méthodes de discrimination multiclasses classiques en utilisant les signaux EEG d’un groupe de sujets sains naïfs, montrant ainsi que les alternatives proposées permettent non seulement d’améliorer l’existant, mais aussi de réduire la complexité de la classification / Brain-Computer Interfaces (BCIs) replace the natural nervous system outputs by artificial ones that do not require the use of peripheral nerves, allowing people with severe motor impairments to interact, only by using their brain activity, with different types of applications, such as spellers, neuroprostheses, wheelchairs, or among others robotics devices. A very popular technique to record signals for BCI implementation purposes consists of electroencephalography (EEG), since in contrast with other alternatives, it is noninvasive and inexpensive. In addition, due to the potentiality of Motor Imagery (MI, i.e., brain oscillations that are generated when subjects imagine themselves performing a movement without actually accomplishing it) to generate suitable patterns for scheming self-paced paradigms, such combination has become a common solution for BCI neuroprostheses design. However, even though important progress has been made in the last years, full 3D control is an unaccomplished objective. In order to explore new solutions for overcoming the existing limitations, we present a multiclass approach that considers the detection of combined motor imageries, (i.e., two or more body parts used at the same time). The proposed paradigm includes the use of the left hand, right hand, and both feet together, from which eight commands are provided to direct a robotic arm comprising fourteen different movements that afford a full 3D control. To this end, an innovative switching-mode scheme that allows managing different actions by using the same command was designed and implemented on the OpenViBE platform. Furthermore, for feature extraction a novel signal processing scheme has been developed based on the specific location of the activity sources that are related to the considered body parts. This insight allows grouping together within a single class those conditions for which the same limb is engaged, in a manner that the original multiclass task is transformed into an equivalent problem involving a series of binary classification models. Such approach allows using the Common Spatial Pattern (CSP) algorithm; which has been shown to be powerful at discriminating sensorimotor rhythms, but has the drawback of being suitable only to differentiate between two classes. Based on this perspective we also have contributed with a new strategy that combines together the CSP algorithm and Riemannian geometry. In which the CSP projected trials are mapped into the Riemannian manifold, from where more discriminative features can be obtained as the distances separating the input data from the considered class means. These strategies were applied on three new classification approaches that have been compared to classical multiclass methods by using the EEG signals from a group of naive healthy subjects, showing that the proposed alternatives not only outperform the existing schema, but also reduce the complexity of the classification task

L'objectif de ce travail est de développer une méthode capable de déterminer automatiquement l'état de vigilance chez l'humain. Les applications envisageables sont multiples. Une telle méthode permettrait par exemple de détecter automatiquement toute modification de l'état de vigilance chez des personnes qui doivent rester dans un état de vigilance élevée (par exemple, les pilotes ou les personnels médicaux).Dans ce travail, les signaux électroencéphalographiques (EEG) de 58 sujets dans deux états de vigilance distincts (état de vigilance haut et bas) ont été recueillis à l'aide d'un casque à 58 électrodes posant ainsi un problème de classification binaire. Afin d'envisager une utilisation de ces travaux sur une application du monde réel, il est nécessaire de construire une méthode de prédiction qui ne nécessite qu'un faible nombre de capteurs (électrodes) afin de limiter le temps de pose du casque à électrodes ainsi que son coût. Au cours de ces travaux de thèse, plusieurs approches ont été développées. Une première approche propose d'utiliser un pré-traitement des signaux EEG basé sur l'utilisation d'une décomposition en ondelettes discrète des signaux EEG afin d'extraire les contributions de chaque fréquence dans le signal. Une régression linéaire est alors effectuée sur les contributions de certaines de ces fréquences et la pente de cette régression est conservée. Un algorithme génétique est utilisé afin d'optimiser le choix des fréquences sur lesquelles la régression est réalisée. De plus, cet algorithme génétique permet la sélection d'une unique électrode.Une seconde approche est basée sur l'utilisation du Common Spatial Pattern (CSP). Cette méthode permet de définir des combinaisons linéaires des variables initiales afin d'obtenir des signaux synthétiques utiles pour la tâche de classification. Dans ce travail, un algorithme génétique ainsi que des méthodes de recherche séquentielle ont été proposés afin de sélectionner un sous groupes d'électrodes à conserver lors du calcul du CSP.Enfin, un algorithme de CSP parcimonieux basé sur l'utilisation des travaux existant sur l'analyse en composantes principales parcimonieuse a été développé.Les résultats de chacune des approches sont détaillés et comparés. Ces travaux ont aboutit sur l'obtention d'un modèle permettant de prédire de manière rapide et fiable l'état de vigilance d'un nouvel individu.

Die derzeit in der Planungspraxis vorzufindende Ausweisung von Siedlungsflächen führt zu einer erheblichen Änderung der bisherigen Siedlungsstrukturen. Weiterhin tritt verstärkt das Problem des Bevölkerungsrückgangs und der Alterung auf. Sowohl im bundesdeutschen Durchschnitt, insbesondere aber in Ostdeutschland, sinkt damit die Nutzungsdichte. Die höhere Inanspruchnahme von Flächen für Siedlungs- und Verkehrszwecke führt außerdem zu einem Verlust einer nicht erneuerbaren Gutes und verändert das Landschaftsbild. Sowohl im Wohn- als auch im gewerblichen Bereich werden die vorhandenen Potenziale zu wenig genutzt. Während innerstädtische Flächen brachfallen, erfolgt die Ausweisung neuer Baugebiete im Außenbereich. Mit einem nachhaltigen regionalen Flächenmanagement sollen der Flächenverbrauch reduziert und eine zukunftsfähige Raumstruktur entwickelt werden. Vor der Diskussion geeigneter Instrumente ist eine kritische Auseinandersetzung mit den gegenwärtigen flächenpolitischen Zielen und deren Optimierung erforderlich. In diesem fünften Band der KoReMi-Schriftenreihe werden daher die flächenpolitischen Ziele unter Schrumpfungsbedingungen diskutiert. Dabei wird zunächst ein theoretischer flächenpolitischer Zielkatalog erarbeitet, der Handlungsziele und Maßnahmen enthält und eine Ableitung flächenpolitischer Strategien ermöglicht. Diesem Katalog werden die gegenwärtigen normativen Aussagen der Landes- und Regionalplanung in der Kernregion Mitteldeutschland gegenübergestellt. Die gewonnenen Erkenntnisse liefern eine wertvolle Grundlage für die Auseinandersetzung mit den gemeindlichen Entwicklungsperspektiven, die als Band 06 dieser Schriftenreihe veröffentlicht werden.