961 resultados para Curson, Jon: New World warblers


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"The greater part of this poem was delivered before the Harvard chapter of the Phi beta kappa society in June, 1911..."-Verso of p. 63.

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"From the Smithsonian report for 1957."

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Motion is a powerful cue for figure-ground segregation, allowing the recognition of shapes even if the luminance and texture characteristics of the stimulus and background are matched. In order to investigate the neural processes underlying early stages of the cue-invariant processing of form, we compared the responses of neurons in the striate cortex (V1) of anaesthetized marmosets to two types of moving stimuli: bars defined by differences in luminance, and bars defined solely by the coherent motion of random patterns that matched the texture and temporal modulation of the background. A population of form-cue-invariant (FCI) neurons was identified, which demonstrated similar tuning to the length of contours defined by first- and second-order cues. FCI neurons were relatively common in the supragranular layers (where they corresponded to 28% of the recorded units), but were absent from layer 4. Most had complex receptive fields, which were significantly larger than those of other V1 neurons. The majority of FCI neurons demonstrated end-inhibition in response to long first- and second-order bars, and were strongly direction selective, Thus, even at the level of V1 there are cells whose variations in response level appear to be determined by the shape and motion of the entire second-order object, rather than by its parts (i.e. the individual textural components). These results are compatible with the existence of an output channel from V1 to the ventral stream of extrastriate areas, which already encodes the basic building blocks of the image in an invariant manner.

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Recent studies have revealed marked differences in the basal dendritic structure of layer III pyramidal cells in the cerebral cortex of adult simian primates. In particular, there is a consistent trend for pyramidal cells of increasing complexity with anterior progression through occipitotemporal cortical visual areas. These differences in pyramidal cell structure, and their systematic nature, are believed to be important for specialized aspects of visual processing within, and between, cortical areas. However, it remains unknown whether this regional specialization in the pyramidal cell phenotype is unique to simians, is unique to primates in general or is widespread amongst mammalian species. In the present study we investigated pyramidal cell structure in the prosimian galago (Otolemur garnetti). We found, as in simians, that the basal dendritic arbors of pyramidal cells differed between cortical areas. More specifically, pyramidal cells became progressively more spinous through the primary (V1), second (V2), dorsolateral (DL) and inferotemporal ( IT) visual areas. Moreover, pyramidal neurons in V1 of the galago are remarkably similar to those in other primate species, in spite of large differences in the sizes of this area. In contrast, pyramidal cells in inferotemporal cortex are quite variable among primate species. These data suggest that regional specialization in pyramidal cell phenotype was a likely feature of cortex in a common ancestor of simian and prosimian primates, but the degree of specialization varies between species. Copyright (C) 2005 S. Karger AG, Basel.

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We tested current hypotheses on the functional organization of the third visual complex, a particularly controversial region of the primate extrastriate cortex. In anatomical experiments, injections of retrograde tracers were placed in the dorsal cortex immediately rostral to the second visual area (V2) of New World monkeys (Callithrix jacchus), revealing the topography of interconnections between the third tier cortex and the primary visual area (V1). The data indicate the presence of a dorsomedial area (DM), which represents the entire upper and lower quadrants of the visual field, and which receives strong, topographically organized projections from the superficial layers of V1. The visuotopic organization and boundaries of DM were confirmed by electrophysiological recordings in the same animals and by architectural characteristics which were distinct from those found in ventral extrastriate cortex rostral to V2. There was no electrophysiological or histological evidence for a transitional area between V2 and DM. In particular, the central representation of the upper quadrant in DM was directly adjacent to the representation of the horizontal meridian that marks the rostral border of V2. The present results argue in favor of the hypothesis that the third visual complex in New World monkeys contains different areas in its dorsal and ventral components: area DM, near the dorsal midline, and a homolog of area 19 of other mammals, located more lateral and ventrally. The characteristics of DM suggest that it may correspond to visual area 6 (V6) of Old World monkeys. (C) 2005 Wiley-Liss, Inc.

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Questions whether the focus on freedom of expression under the Defamation Act 2013 could undermine the value of corporate reputation as a commercial asset.

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Napjainkban a nemzetközi kapcsolatok meghatározó jelensége a gazdasági világválság, amelynek kezelése kapcsán egyre gyakrabban merül fel a politikusok és az elemzők szóhasználatában az „új világrend” fogalma. ____ In treating the current global economic crisis, politicians and analysts increasingly refer to a "new world order". The paper examines this concept, its different meanings and historical evolution, as well as the role it plays in the rhetoric of the Obamaadministration.

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The purpose of this study was to determine if the perceived leadership styles of the leaders at New World School of the Arts were different according to their roles in the organization. The study focused on the top leaders of the organization: the Provost who heads the college program, and the Principal who heads the high school program.^ The Leadership Practices Inventory (LPI) Self and Observer developed by Kouzes and Posner (1990) was used to examine and compare the perceived differences between the leaders and the programs. The LPI measures five practices of exemplary leadership. The LPI Self and Observer was administered to the leaders, administrative subordinates, and faculty. In addition to the LPI a Demographic Inventory was used to collect data about the respondents.^ This study used a causal-comparative design to determine if differences existed between the leaders at NWSA as perceived by the leaders themselves and their respective administrative subordinates and faculty. T tests were conducted on the mean differences between the five leadership practices measured by the LPI. All tests were declared significant if exceeding the 5% level $(p={<}.05).$^ Significant differences were found within the college program across all five practice areas. To a lesser degree, significant differences were found within the high school in three practice areas: Inspiring, Enabling, and Modeling. Three significant differences were found between the college and high school in two practice areas, Enabling and Encouraging.^ There is little consensus of opinion within the college regarding the operative leadership style. Within the high school there is substantial similarity of perception regarding the operative leadership style. There is substantial similarity of perception between the programs regarding the operative leadership style. ^

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In cognitive tests, animals are often given a choice between two options and obtain a reward if they choose correctly. We investigated whether task format affects subjects' performance in a physical cognition test. In experiment 1, a two-choice memory test, 15 marmosets, Callithrix jacchus, had to remember the location of a food reward over time delays of increasing duration. We predicted that their performance would decline with increasing delay, but this was not found. One possible explanation was that the subjects were not sufficiently motivated to choose correctly when presented with only two options because in each trial they had a 50% chance of being rewarded. In experiment 2, we explored this possibility by testing eight naïve marmosets and seven squirrel monkeys, Saimiri sciureus, with both the traditional two-choice and a new nine-choice version of the memory test that increased the cost of a wrong choice. We found that task format affected the monkeys' performance. When choosing between nine options, both species performed better and their performance declined as delays became longer. Our results suggest that the two-choice format compromises the assessment of physical cognition, at least in memory tests with these New World monkeys, whereas providing more options, which decreases the probability of obtaining a reward when making a random guess, improves both performance and measurement validity of memory. Our findings suggest that two-choice tasks should be used with caution in comparisons within and across species because they are prone to motivational biases.

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Soybean Stem Fly (SSF), Melanagromyza sojae (Zehntner), belongs to the family Agromyzidae and is highly polyphagous, attacking many plant species of the family Fabaceae, including soybean and other beans. SSF is regarded as one of the most important pests in soybean fields of Asia (e.g., China, India), North East Africa (e.g., Egypt), parts of Russia, and South East Asia. Despite reports of Agromyzidae flies infesting soybean fields in Rio Grande do Sul State (Brazil) in 1983 and 2009 and periodic interceptions of SSF since the 1940s by the USA quarantine authorities, SSF has not been officially reported to have successfully established in the North and South Americas. In South America, M. sojae was recently confirmed using morphology and its complete mitochondrial DNA (mtDNA) was characterized. In the present study, we surveyed the genetic diversity of M. sojae, collected directly from soybean host plants, using partial mtDNA cytochrome oxidase I (COI) gene, and provide evidence of multiple (>10) maternal lineages in SSF populations in South America, potentially representing multiple incursion events. However, a single incursion involving multiple-female founders could not be ruled out. We identified a haplotype that was common in the fields of two Brazilian states and the individuals collected from Australia in 2013. The implications of SSF incursions in southern Brazil are discussed in relation to the current soybean agricultural practices, highlighting an urgent need for better understanding of SSF population movements in the New World, which is necessary for developing effective management options for this significant soybean pest. © FUNPEC-RP.

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The World Order is a concept in constant mutation that has lost a lot of what characterized it when it was established with the Peace of Westphalia. The conflicts also went through changes. They lost its State distinctiveness and became dispersed and chaotic due to multipolarization. These two concepts share some connections and both dissociated from their traditional definition. This paper aims to establish a connection between the contemporary World Order and the conflicts evolution. The threats to the stability of the World Order contribute to the current disorder and reflects how the conflicts distanced themselves from the clausewitzian battles. To understand how these threats impact the World Order stability and evince the conflicts evolution two cases of study were selected: the nuclear proliferation in Iran and the crisis in Ukraine. These two examples will help establishing the link between the contemporary World Disorder and the conflicts evolution.

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The present Ph.D. thesis proposes three studies on coworking spaces to understand how they foster thriving and organizing in the new world of work. The first study maps and analyzes the thematic structure and evolution of the academic debate that has emerged around coworking spaces in recent years. In doing so, it conducts a science mapping analysis of 351 publications on coworking spaces to detect and visualize key themes in the literature and their co-occurrence with subthemes. The second study proposes an interpretive review of 98 publications from multiple disciplines to shed light on how coworking spaces emerge as sites of organizing for professionals who are not formally connected to one another. It suggests five dimensions that articulate coworking spaces as sites of organizing – ‘materiality,’ ‘temporality,’ ‘affect,’ ‘identity,’ and ‘formalization.’ This study aims to go beyond the community-related understanding of coworking that has characterized most scholarly attention, instead focusing on coworking spaces’ organizational character. The third study investigates what drives thriving at work for remote workers in coworking spaces. In doing so, it acknowledges the potential complex set of interrelationships underpinning thriving at work and mobilizes complexity theory and qualitative comparative analysis to uncover six different, yet equifinal, configurations of antecedents driving remote workers’ thriving in coworking spaces.