479 resultados para nodule


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Nodule is 19'54" musical work for two electronic music performers, two laptop computers and a custom built, sensor-based microphone controller - the e-Mic (Extended Mic-stand Interface Controller). This interface was developed by one of the co-authors, Donna Hewitt. The e-Mic allows a vocal performer to manipulate their voice in real time by capturing physical gestures via an array of sensors - pressure, distance, tilt – in addition to ribbon controllers and an X-Y joystick microphone mount. Performance data are then sent to a computer, running audio-processing software, which is used to transform the audio signal from the microphone in real time. The work seeks to explore the liminal space between the electro-acoustic music tradition and more recent developments in the electronic dance music tradition. It does so on both a performative (gestural) and compositional (sonic) level. Visually, the performance consists of a singer and a laptop performer, hybridising the gestural context of these traditions. On a sonic level, the work explores hybridity at deeper levels of the musical structure than simple bricolage or collage approaches. Hybridity is explored at the level of the sonic gesture (source material), in production (audio processing gestures), in performance gesture, and in approaches to the use of the frequency spectrum, pulse and meter. The work was designed to be performed in a range of contexts from concert halls, to clubs, to rock festivals, across a range of staging and production platforms. As a consequence, the work has been tested in a range of audience contexts, and has allowed the transportation of compositional and performance practices across traditional audience demographic boundaries.

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The presence of Mn-Fe nodules in the epipedons (surface horizons) of paleosols of presumed Upper Neogene age in the northwestern Venezuelan Andes have been interpreted as products of inorganic oxidation and reduction processes operating over the full range of glacial and interglacial cycles that affected paleosol morphogenesis. New microscopic/chemical data from combined SEM-EDS-FIB analyses of representative Mn-Fe nodules indicate microbes play an important role in Mn/Fe precipitation leading to their genesis in alpine Mollisols (Argiustolls). Although the prevailing new data are based mainly on fossil forms of filamentous bacteria and fungi and other biogenic pseudomorphs that may represent the former resident bacteria, the presence of extant microbes must await field experiments/collection, followed by a molecular microbiology approach to determine the biological drivers of metal precipitation. As in other terrestrial niche environments, microbes are seen here to play a role, perhaps a key one, in the morphogenesis of paleosols of importance in upper Neogene paleoenvironmental reconstruction.

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The incidental discovery of a solitary pulmonary nodule while performing a CT scan of the chest is a very common clinical problem. The differential diagnosis is large but the main clinical challenge is to exclude or ascertain a neoplasia. The evaluation of preexisting risk factors and the analysis of morphological characteristics of the nodule allow the clinician to solve this challenge in a significant number of cases. When the nature of the lesion remains indeterminate a careful follow-up with volumetric determination is necessary for decision making.

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Root nodule symbiosis (RNS) is one of the most efficient biological systems for nitrogen fixation and it occurs in 90% of genera in the Papilionoideae, the largest subfamily of legumes. Most papilionoid species show evidence of a polyploidy event occurred approximately 58 million years ago. Although polyploidy is considered to be an important evolutionary force in plants, the role of this papilionoid polyploidy event, especially its association with RNS, is not understood. In this study, we explored this role using an integrated comparative genomic approach and conducted gene expression comparisons and gene ontology enrichment analyses. The results show the following: (1) approximately a quarter of the papilionoid-polyploidy-derived duplicate genes are retained; (2) there is a striking divergence in the level of expression of gene duplicate pairs derived from the polyploidy event; and (3) the retained duplicates are frequently involved in the processes crucial for RNS establishment, such as symbiotic signalling, nodule organogenesis, rhizobial infection and nutrient exchange and transport. Thus, we conclude that the papilionoid polyploidy event might have further refined RNS and induced a more robust and enhanced symbiotic system. This conclusion partly explains the widespread occurrence of the Papilionoideae.

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A method is presented for identification of lung nodules. It includes three stages: image acquisition, background removal, and nodule detection. The first stage improves image quality. The second stage extracts long lobe regions. The third stage detects lung nodules. The method is based on the random forest learner. Training set contains nodule, non-nodule, and false-positive patterns. Test set contains randomly selected images. The developed method is compared against the support vector machine. True-positives of 100% and 85.9%, and false-positives of 1.27 and 1.33 per image were achieved by the developed method and the support vector machine, respectively.

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Lung nodule refers to lung tissue abnormalities that may become cancerous. An automated system that detects nodules of common sizes within lung images is developed. It consists of acquisition, pre-processing, background removal, nodule detection, and false positives reduction. The system can assist expert radiologists in their decision making.

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Lung nodules can be detected through examining CT scans. An automated lung nodule classification system is presented in this paper. The system employs random forests as it base classifier. A unique architecture for classification-aided-by-clustering is presented. Four experiments are conducted to study the performance of the developed system. 5721 CT lung image slices from the LIDC database are employed in the experiments. According to the experimental results, the highest sensitivity of 97.92%, and specificty of 96.28% are achieved by the system. The results demonstrate that the system has improved the performances of its tested counterparts.

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An automated lung nodule detection system can help spot lung abnormalities in CT lung images. Lung nodule detection can be achieved using template-based, segmentation-based, and classification-based methods. The existing systems that include a classification component in their structures have demonstrated better performances than their counterparts. Ensemble learners combine decisions of multiple classifiers to form an integrated output. To improve the performance of automated lung nodule detection, an ensemble classification aided by clustering (CAC) method is proposed. The method takes advantage of the random forest algorithm and offers a structure for a hybrid random forest based lung nodule classification aided by clustering. Several experiments are carried out involving the proposed method as well as two other existing methods. The parameters of the classifiers are varied to identify the best performing classifiers. The experiments are conducted using lung scans of 32 patients including 5721 images within which nodule locations are marked by expert radiologists. Overall, the best sensitivity of 98.33% and specificity of 97.11% have been recorded for proposed system. Also, a high receiver operating characteristic (ROC) Az of 0.9786 has been achieved.

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The anatomy and ultrastructure of root nodules of Anadenanthera peregrina var. falcata (Leguminosae-Mimosoideae) were analysed, as was plant growth. To ensure that nodules developed, seedlings were inoculated with a mixture of six strains of rhizobia. Nodules were produced that differed in appearance-and probably also effectiveness-but their structure was similar and they showed characteristics typical of indeterminate nodules, such as persistent meristematic tissue and a gradient of cells at different stages of development. Many starch grains were present in inner cortex cells and interstitial cells of infected tissue. Infected cells were densely packed with bacteroids, which contained many poly-beta-hydroxybutyrate granules. The high incidence of these granules, together with high levels of starch accumulation in interstitial cells, suggested low N-2-fixation efficiency of the rhizobia isolates used for inoculation. In the symbiosomes of early-senescent infected cells, reticulum-like structures, small vesicles and a fibrillar material were observed; these may be related to bacteroid degradation. In the cytoplasm of late-senescent infected cells, many vesicles and membrane-like structures were observed, probably associated with membrane degradation of bacteroids and peribacteroids. The total biomass of plants inoculated with rhizobia was low and their xylopodia and shoots had low levels of N compared with non-inoculated plants fertilized with ammonium nitrate. However, inoculated plants did not show N-deficiency symptoms and grew better than non-inoculated plants without N fertilization. These growth results, together with ultrastructural observations of nodules, suggest that nitrogen fixation of rhizobia isolates associated with Anadenanthera peregrina var. falcata roots is poor. (C) 2002 Annals of Botany Company.

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Insects manifest effective immune responses that include both cellular and humoral components. Morphological and quantitative aspects of cellular and Immoral cooperation during nodule formation in Chrysomya megacephala hemolymph against Saccharomyces cerevisae yeast cells were demonstrated for the first time. The analyses were performed in non-injected larvae (NIL), saline-injected larvae (SIL) and yeast-injected larvae (YIL). The hemolymph of injected groups was collected 0.5, 1, 2, 4, 12, 24, 36, or 48-h post-injection. Morphological aspects of YIL nodulation were investigated using transmission electron microscopy (TEM). Quantitative analyses consisted of total (THC) and differential hemocyte counts (DHC) in all the groups and total yeast count (TYC) in YIL, which were performed in an improved Neubauer chamber. Nodule formation was initiated at approximately 2-h post-injection. Twelve hours after the injection, TEM revealed the presence of an amorphous membrane, at the same time that circulating hemocyte number decreased significantly contrasting the increase of yeast number. Our results showed the ability of C megacephala hemolymph to perform humoral encapsulation when hemocyte population is insufficient to eliminate the microorganisms, warranting consideration in future investigations on the relative roles played by cellular and humoral elements of innate immunity of this calliphorid. (c) 2007 Elsevier B.V. All rights reserved.

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Endometrial stromal sarcoma is a rare neoplasm of the uterus. Extrauterine locations of this neoplasm, excluding metastases or local extension, are even more unusual and are usually associated with the presence of endometriosis. The authors report a case of endometrial stromal sarcoma presenting as a vaginal wall nodule, without any sign of primary uterine tumor after extensive evaluation or presence of endometriosis. The morphology, immunohistochemical profile, differential diagnoses, and pathogenesis are discussed, as well as a review of the literature on this issue. © 2004 Elsevier Inc. All rights reserved.

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The Sister Mary Joseph (SMJ) nodule is a clinical sign of metastatic cancer involving the umbilicus. The vast majority of these instances represent adenocarcinomas arising from ovarian or colorectal primaries. We present a patient who presented with ascites and the SMJ lesion that turned out to be a metastatic gastrointestinal stromal tumor after fine needle aspiration biopsy was performed. The lesion was subsequently histologically confirmed. Gastrointestinal stroma tumor involving the umbilicus is exceedingly uncommon and only rarely presents in this fashion. The cytomorphological features, differential diagnosis, and comparison with the tissue specimen are made. © 2006 Elsevier Inc. All rights reserved.

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This letter describes a novel algorithm that is based on autoregressive decomposition and pole tracking used to recognize two patterns of speech data: normal voice and disphonic voice caused by nodules. The presented method relates the poles and the peaks of the signal spectrum which represent the periodic components of the voice. The results show that the perturbation contained in the signal is clearly depicted by pole's positions. Their variability is related to jitter and shimmer. The pole dispersion for pathological voices is about 20% higher than for normal voices, therefore, the proposed approach is a more trustworthy measure than the classical ones. © 2007.