732 resultados para solitary Oxaea flavescens


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Recent developments in nonlinear optics reveal an interesting class of pulses with a parabolic intensity profile in the energy-containing core and a linear frequency chirp that can propagate in a fiber with normal group-velocity dispersion. Parabolic pulses propagate in a stable selfsimilar manner, holding certain relations (scaling) between pulse power, width, and chirp parameter. In the additional presence of linear amplification, they enjoy the remarkable property of representing a common asymptotic state (or attractor) for arbitrary initial conditions. Analytically, self-similar (SS) parabolic pulses can be found as asymptotic, approximate solutions of the nonlinear Schr¨odinger equation (NLSE) with gain in the semi-classical (largeamplitude/small-dispersion) limit. By analogy with the well-known stable dynamics of solitary waves - solitons, these SS parabolic pulses have come to be known as similaritons. In practical fiber systems, inherent third-order dispersion (TOD) in the fiber always introduces a certain degree of asymmetry in the structure of the propagating pulse, eventually leading to pulse break-up. To date, there is no analytic theory of parabolic pulses under the action of TOD. Here, we develop aWKB perturbation analysis that describes the effect of weak TOD on the parabolic pulse solution of the NLSE in a fiber gain medium. The induced perturbation in phase and amplitude can be found to any order. The theoretical model predicts with sufficient accuracy the pulse structural changes induced by TOD, which are observed through direct numerical NLSE simulations.

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Recent developments in nonlinear optics reveal an interesting class of pulses with a parabolic intensity profile in the energy-containing core and a linear frequency chirp that can propagate in a fiber with normal group-velocity dispersion. Parabolic pulses propagate in a stable selfsimilar manner, holding certain relations (scaling) between pulse power, width, and chirp parameter. In the additional presence of linear amplification, they enjoy the remarkable property of representing a common asymptotic state (or attractor) for arbitrary initial conditions. Analytically, self-similar (SS) parabolic pulses can be found as asymptotic, approximate solutions of the nonlinear Schr¨odinger equation (NLSE) with gain in the semi-classical (largeamplitude/small-dispersion) limit. By analogy with the well-known stable dynamics of solitary waves - solitons, these SS parabolic pulses have come to be known as similaritons. In practical fiber systems, inherent third-order dispersion (TOD) in the fiber always introduces a certain degree of asymmetry in the structure of the propagating pulse, eventually leading to pulse break-up. To date, there is no analytic theory of parabolic pulses under the action of TOD. Here, we develop aWKB perturbation analysis that describes the effect of weak TOD on the parabolic pulse solution of the NLSE in a fiber gain medium. The induced perturbation in phase and amplitude can be found to any order. The theoretical model predicts with sufficient accuracy the pulse structural changes induced by TOD, which are observed through direct numerical NLSE simulations.

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Historically, research has placed considerable emphasis on developing a systematic body of knowledge about education in which little voice has been given to teachers themselves. The critical role that teachers play in this generative process such as reflecting, acting and theorizing upon practices that shape life in the classroom has largely been ignored in favor of technical innovation and organizational procedure. As schools struggle to reform and restructure, an understanding of how teachers interpret their practices in context and how the culture of schools influence, constrain, or encourage these practices become critical aspects of school success or failure. ^ This study examined the perspectives on inclusion of seven middle school teachers as they attempted to include exceptional students in regular classes. The study utilized three forms of data collection: observations were made of participant interactions as they led their everyday school lives; document analysis was used as a means to gain an understanding of programs affecting exceptional students, and interviews were used to give voice to teacher's perceptions regarding inclusion, allowing description in their own words rather than those imposed by an outside inquirer. Data collection and analysis sought to identify emerging themes, categories and patterns, allowing for the creation of substantive theory grounded in empirical data. ^ The key issues that emerged in the study were considered in terms of three general categories. The first, teaching and learning, revealed stark contrasts in opinions regarding the type of human support thought necessary for successful inclusion. Regular educators clung to the traditional notion of solitary teachers directing all class activity, while exceptional educators preferred a more team-oriented approach. The second, school structure, revealed that highly collaborative structures were only partially successful in creating additional conversation between regular and exceptional educators. Collegiality was affected by lack of staff experience with the process as well as its implementation in a top-down fashion. The third, school culture and climate, revealed that regular educators believed the school was prepared for a limited amount of inclusion. Although exceptional educators acknowledged school readiness, they did not believe that inclusion was an important item on the school's reform agenda. ^

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Cetaceans are aquatic mammals that rely primarily on sound for most daily tasks. A compendium of sounds is emitted for orientation, prey detection, and predator avoidance, and to communicate. Communicative sounds are among the most studied Cetacean signals, particularly those referred to as tonal sounds. Because tonal sounds have been studied especially well in social dolphins, it has been assumed these sounds evolved as a social adaptation. However, whistles have been reported in ‘solitary’ species and have been secondarily lost three times in social lineages. Clearly, therefore, it is necessary to examine closely the association, if any, between whistles and sociality instead of merely assuming it. Several hypotheses have been proposed to explain the evolutionary history of Cetacean tonal sounds. The main goal of this dissertation is to cast light on the evolutionary history of tonal sounds by testing these hypotheses by combining comparative phylogenetic and field methods. This dissertation provides the first species-level phylogeny of Cetacea and phylogenetic tests of evolutionary hypotheses of cetacean communicative signals. Tonal sounds evolution is complex in that has likely been shaped by a combination of factors that may influence different aspects of their acoustical structure. At the inter-specific level, these results suggest that only tonal sound minimum frequency is constrained by body size. Group size also influences tonal sound minimum frequency. Species that live in large groups tend to produce higher frequency tonal sounds. The evolutionary history of tonal sounds and sociality may be intertwined, but in a complex manner rejecting simplistic views such as the hypothesis that tonal sounds evolved ‘for’ social communication in dolphins. Levels of social and tonal sound complexity nevertheless correlate indicating the importance of tonal sounds in social communication. At the intraspecific level, tonal sound variation in frequency and temporal parameters may be product of genetic isolation and local levels of underwater noise. This dissertation provides one of the first insights into the evolution of Cetacean tonal sounds in a phylogenetic context, and points out key species where future studies would be valuable to enrich our understanding of other factors also playing a role in tonal sound evolution. ^

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Since multimedia data, such as images and videos, are way more expressive and informative than ordinary text-based data, people find it more attractive to communicate and express with them. Additionally, with the rising popularity of social networking tools such as Facebook and Twitter, multimedia information retrieval can no longer be considered a solitary task. Rather, people constantly collaborate with one another while searching and retrieving information. But the very cause of the popularity of multimedia data, the huge and different types of information a single data object can carry, makes their management a challenging task. Multimedia data is commonly represented as multidimensional feature vectors and carry high-level semantic information. These two characteristics make them very different from traditional alpha-numeric data. Thus, to try to manage them with frameworks and rationales designed for primitive alpha-numeric data, will be inefficient. An index structure is the backbone of any database management system. It has been seen that index structures present in existing relational database management frameworks cannot handle multimedia data effectively. Thus, in this dissertation, a generalized multidimensional index structure is proposed which accommodates the atypical multidimensional representation and the semantic information carried by different multimedia data seamlessly from within one single framework. Additionally, the dissertation investigates the evolving relationships among multimedia data in a collaborative environment and how such information can help to customize the design of the proposed index structure, when it is used to manage multimedia data in a shared environment. Extensive experiments were conducted to present the usability and better performance of the proposed framework over current state-of-art approaches.

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The purpose of this project is to ascertain the ways in which Orange is the New Black uses its platform to either complicate or reify narratives about the prison system, prisoners and their relationship to the state. This research uses the works of Giorgio Agamben, Colin Dayan, Michelle Alexander and Lisa Guenther to situate the ways the state uses the prison and social narratives about the prison to extend its control on certain populations beyond prison walls through police presence, parole, the war on drugs and prison fees. From that basis, this work argues that while Orange does challenge some narratives about race and sexuality, because of its reliance on “bad choices” as a humanizing trope and its reliance on certain racialized stereotypes for entertainment, the show ultimately does more to reify existing narratives that support state interests.

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Cetaceans are aquatic mammals that rely primarily on sound for most daily tasks. A compendium of sounds is emitted for orientation, prey detection, and predator avoidance, and to communicate. Communicative sounds are among the most studied Cetacean signals, particularly those referred to as tonal sounds. Because tonal sounds have been studied especially well in social dolphins, it has been assumed these sounds evolved as a social adaptation. However, whistles have been reported in ‘solitary’ species and have been secondarily lost three times in social lineages. Clearly, therefore, it is necessary to examine closely the association, if any, between whistles and sociality instead of merely assuming it. Several hypotheses have been proposed to explain the evolutionary history of Cetacean tonal sounds. The main goal of this dissertation is to cast light on the evolutionary history of tonal sounds by testing these hypotheses by combining comparative phylogenetic and field methods. This dissertation provides the first species-level phylogeny of Cetacea and phylogenetic tests of evolutionary hypotheses of cetacean communicative signals. Tonal sounds evolution is complex in that has likely been shaped by a combination of factors that may influence different aspects of their acoustical structure. At the inter-specific level, these results suggest that only tonal sound minimum frequency is constrained by body size. Group size also influences tonal sound minimum frequency. Species that live in large groups tend to produce higher frequency tonal sounds. The evolutionary history of tonal sounds and sociality may be intertwined, but in a complex manner rejecting simplistic views such as the hypothesis that tonal sounds evolved ‘for’ social communication in dolphins. Levels of social and tonal sound complexity nevertheless correlate indicating the importance of tonal sounds in social communication. At the intraspecific level, tonal sound variation in frequency and temporal parameters may be product of genetic isolation and local levels of underwater noise. This dissertation provides one of the first insights into the evolution of Cetacean tonal sounds in a phylogenetic context, and points out key species where future studies would be valuable to enrich our understanding of other factors also playing a role in tonal sound evolution.

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The metabolic rate of organisms may either be viewed as a basic property from which other vital rates and many ecological patterns emerge and that follows a universal allometric mass scaling law; or it may be considered a property of the organism that emerges as a result of the organism's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from previous compilations by other authors. Data were read from tables or digitized from graphs. Only measurements made on individuals of know size, or groups of individuals of similar and known size were included. We show that clearance and respiration rates have life-form-dependent allometries that have similar scaling but different elevations, such that the mass-specific rates converge on a rather narrow size-independent range. In contrast, ingestion and growth rates follow a near-universal taxa-independent ~3/4 mass scaling power law. We argue that the declining mass-specific clearance rates with size within taxa is related to the inherent decrease in feeding efficiency of any particular feeding mode. The transitions between feeding mode and simultaneous transitions in clearance and respiration rates may then represent adaptations to the food environment and be the result of the optimization of tradeoffs that allow sufficient feeding and growth rates to balance mortality.

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The metabolic rate of organisms may either be viewed as a basic property from which other vital rates and many ecological patterns emerge and that follows a universal allometric mass scaling law; or it may be considered a property of the organism that emerges as a result of the organism's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from previous compilations by other authors. Data were read from tables or digitized from graphs. Only measurements made on individuals of know size, or groups of individuals of similar and known size were included. We show that clearance and respiration rates have life-form-dependent allometries that have similar scaling but different elevations, such that the mass-specific rates converge on a rather narrow size-independent range. In contrast, ingestion and growth rates follow a near-universal taxa-independent ~3/4 mass scaling power law. We argue that the declining mass-specific clearance rates with size within taxa is related to the inherent decrease in feeding efficiency of any particular feeding mode. The transitions between feeding mode and simultaneous transitions in clearance and respiration rates may then represent adaptations to the food environment and be the result of the optimization of tradeoffs that allow sufficient feeding and growth rates to balance mortality.

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The maned wolf (Chrysocyon brachyurus Illiger 1815) is the biggest canid in South America and it is considered a “near threatened” species by IUCN. Because of its nocturnal, territorial and solitary habits, there are still many understudied aspects of their behavior in natural environments, including acoustic communication. In its vocal repertoire, the wolf presents a longdistance call named “roar-bark” which, according to literature, functions for spacing maintenance between individuals and/or communication between members of the reproductive pair inside the territory. In this context, this study aimed: 1) to compare four methods for detecting maned wolf’s roar-barks in recordings made in a natural environment, in order to elect the most efficient one for our project; 2) to understand the night emission pattern of these vocalizations, verifying possible weather and moon phases influences in roarbark’s emission rates; and 3) to test Passive Acoustic Monitoring as a tool to identify the presence of maned wolves in a natural environment. The study area was the Serra da Canastra National Park (Minas Gerais, Brazil), where autonomous recorders were used for sound acquisition, recording all night (from 06pm to 06am) during five days in December/2013 and every day from April to July/2014. Roar-barks’ detection methods were tested and compared regarding time needed to analyze files, number of false positives and number of correctly identified calls. The mixed method (XBAT + manual) was the most efficient one, finding 100% of vocalizations in almost half of the time the manual method did, being chosen for our data analysis. By studying roarbarks’ temporal variation we verified that the wolves vocalize more in the early hours of the evening, suggesting an important social function for those calls at the beginning of its period of most intense activity. Average wind speed negatively influenced vocalization rate, which may indicate lower sound reception of recorders or a change in behavioral patterns of wolves in high speed wind conditions. A better understanding of seasonal variation of maned wolves’ vocal activity is required, but our study already shows that it is possible to detect behavioral patterns of wild animals only by sound, validating PAM as a tool in this species’ conservation.

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Lung cancer is one of the most common types of cancer and has the highest mortality rate. Patient survival is highly correlated with early detection. Computed Tomography technology services the early detection of lung cancer tremendously by offering aminimally invasive medical diagnostic tool. However, the large amount of data per examination makes the interpretation difficult. This leads to omission of nodules by human radiologist. This thesis presents a development of a computer-aided diagnosis system (CADe) tool for the detection of lung nodules in Computed Tomography study. The system, called LCD-OpenPACS (Lung Cancer Detection - OpenPACS) should be integrated into the OpenPACS system and have all the requirements for use in the workflow of health facilities belonging to the SUS (Brazilian health system). The LCD-OpenPACS made use of image processing techniques (Region Growing and Watershed), feature extraction (Histogram of Gradient Oriented), dimensionality reduction (Principal Component Analysis) and classifier (Support Vector Machine). System was tested on 220 cases, totaling 296 pulmonary nodules, with sensitivity of 94.4% and 7.04 false positives per case. The total time for processing was approximately 10 minutes per case. The system has detected pulmonary nodules (solitary, juxtavascular, ground-glass opacity and juxtapleural) between 3 mm and 30 mm.

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Neurilemmomas arising from Schwann cells, rarely found in oral cavity, are characterized by solitary occurrence, slow growth and smooth surface with variable clinical aspects, depending on the nerve origin. Most instances are typically asymptomatic. Microscopically, the histopathological characteristic consists of alternating regions of hypercellularity and hypocellularity such as Antoni A and Antoni B, respectively. The prognosis is favorable; complete surgical removal is the treatment of choice, no recurrence should be expected. The present report shows the case of neurilemmoma in bucal mucosa, in a 9-year-old child. Patient was referred to the Stomatology Clinic of School of Dentistry, Universidade Federal do Rio Grande do Norte, with complaint of nodular mass, with approximately one year development. Patient was submitted to excisional biopsy, with histopathological exam showing diagnosis of neurilemmoma. After 1 year follow-up there has been no recurrence of lesion.

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Neurilemmomas arising from Schwann cells, rarely found in oral cavity, are characterized by solitary occurrence, slow growth and smooth surface with variable clinical aspects, depending on the nerve origin. Most instances are typically asymptomatic. Microscopically, the histopathological characteristic consists of alternating regions of hypercellularity and hypocellularity such as Antoni A and Antoni B, respectively. The prognosis is favorable; complete surgical removal is the treatment of choice, no recurrence should be expected. The present report shows the case of neurilemmoma in bucal mucosa, in a 9-year-old child. Patient was referred to the Stomatology Clinic of School of Dentistry, Universidade Federal do Rio Grande do Norte, with complaint of nodular mass, with approximately one year development. Patient was submitted to excisional biopsy, with histopathological exam showing diagnosis of neurilemmoma. After 1 year follow-up there has been no recurrence of lesion.

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Through the creation of this project in English, we have made a file of radiographic images that will be used by third year dental students in order to improve the practical teaching part of the subject of Oral Medicine, essentially by incorporating these files to the Virtual Campus. We have selected the most representative radiopaque radiographic images studied in pathology lectures given. We have prepared a file with 59 radiopaque radiographic images. These lesions have been divided according to their relationship and number with the tooth, into the following groups: “Anatomic radiopacities”, “Periapical radiopacities”, “Solitary radiopacities not necessarily contacting teeth”,“Multiple separate radiopacities”, and “Generalized radiopacities”. We created 4 flowcharts synthesizing the mayor explanatory bases of each pathological process in relation to other pathologies within each location. We have focused primarily in those clinical and radiographic features that can help us differentiate one pathology from another. We believe that by giving the student a knowledge base through each flowchart, as well as provide clinical cases, will start their curiosity to seek new cases on the Internet or try to look for images that we have not been able to locate due to low frequency. In addition, as this project has been done in English, it will provide the students with necessary tools to do a literature search, as most of the medical and dental literature is in English; thus far, providing the student with this material necessary to make the appropriate searched using keywords in English.

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The Carmelite friars were the last of the major mendicant orders to be established in Italy. Originally an eremitical order, they arrived from the Holy Land in the 1240s, decades after other mendicant orders, such as the Franciscans and Dominicans, had constructed churches and cultivated patrons in the burgeoning urban centers of central Italy. In a religious market already saturated with friars, the Carmelites distinguished themselves by promoting their Holy Land provenance, eremitical values, and by developing an institutional history claiming to be descendants of the Old Testament prophet Elijah. By the end of the 13th century the order had constructed thriving churches and convents and leveraged itself into a prominent position in the religious community. My dissertation analyzes these early Carmelite churches and convents, as well as the friars’ interactions with patrons, civic governments, and the urban space they occupied. Through three primary case studies – the churches and convents of Pisa, Siena and Florence – I examine the Carmelites’ approach to art, architecture, and urban space as the order transformed its mission from one of solitary prayer to one of active ministry.

My central questions are these: To what degree did the Carmelites’ Holy Land provenance inform the art and architecture they created for their central Italian churches? And to what degree was their visual culture instead a reflection of the mendicant norms of the time?

I have sought to analyze the Carmelites at the institutional level, to determine how the order viewed itself and how it wanted its legacy to develop. I then seek to determine how and if the institutional model was utilized in the artistic and architectural production of the individual convents. The understanding of Carmelite art as a promotional tool for the identity of the order is not a new one, however my work is the first to consider deeply the order’s architectural aspirations. I also consider the order’s relationships with its de facto founding saint, the prophet Elijah, and its patron, the Virgin Mary, in a more comprehensive manner that situates the resultant visual culture into the contemporary theological and historical contexts.