930 resultados para Codes and repertoires of language


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This dissertation establishes a novel data-driven method to identify language network activation patterns in pediatric epilepsy through the use of the Principal Component Analysis (PCA) on functional magnetic resonance imaging (fMRI). A total of 122 subjects’ data sets from five different hospitals were included in the study through a web-based repository site designed here at FIU. Research was conducted to evaluate different classification and clustering techniques in identifying hidden activation patterns and their associations with meaningful clinical variables. The results were assessed through agreement analysis with the conventional methods of lateralization index (LI) and visual rating. What is unique in this approach is the new mechanism designed for projecting language network patterns in the PCA-based decisional space. Synthetic activation maps were randomly generated from real data sets to uniquely establish nonlinear decision functions (NDF) which are then used to classify any new fMRI activation map into typical or atypical. The best nonlinear classifier was obtained on a 4D space with a complexity (nonlinearity) degree of 7. Based on the significant association of language dominance and intensities with the top eigenvectors of the PCA decisional space, a new algorithm was deployed to delineate primary cluster members without intensity normalization. In this case, three distinct activations patterns (groups) were identified (averaged kappa with rating 0.65, with LI 0.76) and were characterized by the regions of: (1) the left inferior frontal Gyrus (IFG) and left superior temporal gyrus (STG), considered typical for the language task; (2) the IFG, left mesial frontal lobe, right cerebellum regions, representing a variant left dominant pattern by higher activation; and (3) the right homologues of the first pattern in Broca's and Wernicke's language areas. Interestingly, group 2 was found to reflect a different language compensation mechanism than reorganization. Its high intensity activation suggests a possible remote effect on the right hemisphere focus on traditionally left-lateralized functions. In retrospect, this data-driven method provides new insights into mechanisms for brain compensation/reorganization and neural plasticity in pediatric epilepsy.

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This dissertation establishes a novel data-driven method to identify language network activation patterns in pediatric epilepsy through the use of the Principal Component Analysis (PCA) on functional magnetic resonance imaging (fMRI). A total of 122 subjects’ data sets from five different hospitals were included in the study through a web-based repository site designed here at FIU. Research was conducted to evaluate different classification and clustering techniques in identifying hidden activation patterns and their associations with meaningful clinical variables. The results were assessed through agreement analysis with the conventional methods of lateralization index (LI) and visual rating. What is unique in this approach is the new mechanism designed for projecting language network patterns in the PCA-based decisional space. Synthetic activation maps were randomly generated from real data sets to uniquely establish nonlinear decision functions (NDF) which are then used to classify any new fMRI activation map into typical or atypical. The best nonlinear classifier was obtained on a 4D space with a complexity (nonlinearity) degree of 7. Based on the significant association of language dominance and intensities with the top eigenvectors of the PCA decisional space, a new algorithm was deployed to delineate primary cluster members without intensity normalization. In this case, three distinct activations patterns (groups) were identified (averaged kappa with rating 0.65, with LI 0.76) and were characterized by the regions of: 1) the left inferior frontal Gyrus (IFG) and left superior temporal gyrus (STG), considered typical for the language task; 2) the IFG, left mesial frontal lobe, right cerebellum regions, representing a variant left dominant pattern by higher activation; and 3) the right homologues of the first pattern in Broca's and Wernicke's language areas. Interestingly, group 2 was found to reflect a different language compensation mechanism than reorganization. Its high intensity activation suggests a possible remote effect on the right hemisphere focus on traditionally left-lateralized functions. In retrospect, this data-driven method provides new insights into mechanisms for brain compensation/reorganization and neural plasticity in pediatric epilepsy.

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The quarrel, in this study, tells about the language as social practical in the daily of Parnamirim State Prison that is integrated to the Rio Grande do Norte Penitentiary System - SISPERN, destined for men in fulfilment of penalty privative of freedom, in closed regimen. For the accomplishment of the research, the delimited objectives had been to analyze the language repertoires created in the prisional daily, trying to identify how it´s turned into distinct forms of resistance to the mechanisms of control in penitentiary system; to investigate which are the language repertoires created from the new sociability forms developed among prisoners and identify how the language repertoires are expressed in the daily prisional on relations/exercises of power not-institutionalized. In the methodological aspect, the study is in a qualitative boarding, that has as main instrument the interview. The inquiry was possible by means of using instruments for data collection, like as: the direct comment in the prisional daily duly registered as researcher´s ethnographical procedure, the analysis of interns´ cadastre handbooks and the application of half-structuralized interview, to the subjects of the research. The construction and understanding of the study object had been based on authors who argue on the arrest, as: Foucault, Goffman, Carvalho Filho and, in particular was searched the theorical referencial that approaches the language in a social and cultural perspective: Orlandi, Manfred, Bastos and Candiotto, amongst others. Beyond the normative endorsement of the Brazilian legislation, through the Law of Criminal Execution, of the Criminal Code and the Federal Constitution of the country and the legal apparatus in state scope. Still in the research methodological perspective, after the collection the data had been submitted to an analysis of the speech from Foucalt´s theory and in the Orlandi´s perspective, being also qualitative and quantitative. The results had evidenced that the social and juridical profile of the population in the site inquired is not different of others Brazilian prisons, composed for men, in its majority, with age band between 21 and 30 years old, prisoners for practicing crimes against the patrimony, against life, amongst others, and, in special, criminal recidivists. It evidenced, still, that the daily prisional of PSP is characterized for a sociocultural diversity expressed in the relations of power not institutionalized, that contributes for the formation and division of the groups, each one using a set of language codes/ repertoires sustentation. Therefore, the language, in the daily prisional, is one of the ways to understand the singularity of the sociability relations and as social practicing mediated by relations/exercises of power and antagonistic interests, in which each group aims first of all, their own interests. It represents the complexity of the social relations, in the prisional space, with diverse effects, in function of the situation and the moment. The language in the arrest, beyond the communication function, assumes and represents central element for the sociability human being, contributes for its changings and it´s configured as one of the resistance forms of prisoners against the controling, disciplining and monitoring mechanisms of penitentiary system

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A variety of language disturbances including aphasia have been described after subcortical stroke but less is known about the factors that influence the long-term recovery of stroke-induced language dysfunction. We prospectively examined the role of the affected hemisphere and the lesion site in the occurrence and recovery of language deficits in nonthalamic subcortical stroke. Forty patients with unilateral basal gangliastroke underwent language assessment within 1 week, 3 months and 1 year after stroke. Disturbances in at least one language domain were observed in 35 patients during the first week post stroke including aphasia diagnosed in 11 patients. Importantly, the appearance of deficits after stroke onset and the improvement of language function were not determined by the site of subcortical lesion, but instead were critically influenced by the affected hemisphere. In fact, the language impairments following left and right basal ganglia stroke mirrored the language dysfunction observed after cortical lesions in the same hemisphere. A significant overall language improvement was observed at 3 months after stroke, although residual deficits in languageexecutive function were the most commonly observed impairment at 1 year follow-up. Although a substantial improvement of language function can be expected after nonthalamic subcortical stroke, our findings suggest that language recovery may not be fully achieved at 1 year post

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Native speakers learn their mother tongue slowly, from birth, by the constant repetition of common words and phrases in a variety of contexts and situations, within the language community. As foreign language learners, we face considerable disadvantages when compared to children learning their mother tongue. Foreign language learners start later in life, have less time, have fewer opportunities to experience the language, and learn in the restricted environment of the classroom. Teachers and books give us information about many words and phrases, but it is difficult for us to know what we need to focus on and learn thoroughly, and what is less important. The rules and explanations are often difficult for us to understand. A large language corpus represents roughly the amount and variety of language that a native-speaker experiences in a whole lifetime. Learners can now access language corpora. We can check which words and phrases are important, and quickly discover their common meanings, collocations, and structural patterns. It is easier to remember things that we find out ourselves, rather than things that teachers or books tell us. Each click on the computer keyboard can show us the same information in different ways, so we can understand it more easily. We can also get many more examples from a corpus. Teachers and native-speakers can also use corpora, to confirm and enhance their own knowledge of a language, and prepare exercises to guide their students. Each of us can learn at our own level and at our own speed.

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The purpose of this study is to investigate the effects of bilingual and monolingual videos on the reading comprehension of students with significant hearing impairments and/or deafness. Children with and without hearing losses need reading programs in which comprehension of meaning is the primary goal. This can occur only when print is represented in meaningful context, allowing children to create meaning from their own experience, background, and knowledge of language.^ Investigated in this study was whether students with significant hearing losses comprehended more information in a bilingual or monolingual instructional video format. There were three instructional videos produced: (a) the bilingual video which incorporated American Sign Language (ASL) with standard English captions, (b) a monolingual English video with standard English captions only, and (c) a monolingual ASL-only video. It was hypothesized that the effects of English captioning with ASL might serve as a bridge during instruction, increasing reading comprehension and written English for students. It was further hypothesized that this would allow students to integrate their own ASL knowledge to the printed text to construct meaning.^ Four separate analyses were conducted to see if the hypothesis was supported by the findings. However, all results indicated that there were no significant differences in students' written measures of reading comprehension recall across any of the three presentations of information (two monolingual and one bilingual condition). There were seven variables (word identification, word recall, sentence recall, story recall, written passage theme, written passage word count, and number of mature words) used to evaluate reading comprehension recall. No variable, either individually or grouped, demonstrated a significant difference between monolingual or bilingual instruction. ^

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The influence of initial perturbation geometry and material propel-ties on final fold geometry has been investigated using finite-difference (FLAC) and finite-element (MARC) numerical models. Previous studies using these two different codes reported very different folding behaviour although the material properties, boundary conditions and initial perturbation geometries were similar. The current results establish that the discrepancy was not due to the different computer codes but due to the different strain rates employed in the two previous studies (i.e. 10(-6) s(-1) in the FLAC models and 10(-14) s(-1) in the MARC models). As a result, different parts of the elasto-viscous rheological field were bring investigated. For the same material properties, strain rate and boundary conditions, the present results using the two different codes are consistent. A transition in Folding behaviour, from a situation where the geometry of initial perturbation determines final fold shape to a situation where material properties control the final geometry, is produced using both models. This transition takes place with increasing strain rate, decreasing elastic moduli or increasing viscosity (reflecting in each case the increasing influence of the elastic component in the Maxwell elastoviscous rheology). The transition described here is mechanically feasible but is associated with very high stresses in the competent layer (on the order of GPa), which is improbable under natural conditions. (C) 2000 Elsevier Science Ltd. All rights reserved.

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Objectives: Depression and dementia are highly prevalent in the elderly. Language impairment is an inherent component of Alzheimer`s disease (AD), which can also be encountered in depressed patients. The aim of this study wasto compare the profiles of language abilities in late-onset depression and mild AD groups. Methods: We studied 25 patients with late-onset depression (mean age 73.6 +/- 6.6 years; schooling 9.1 +/- 5.7 years) and 30 patients with mild AD (77.6 +/- 5.4 years; 7.5 +/- 7.1 years) using the Arizona Battery for Communication Disorders of Dementia (ABCD), compared to a group of 30 controls (73.8 +/- 5.8 years; 9.1 +/- 5.4 years). Cut-off scores to discriminate between Controls x Depression and Depression x AD were determined. Results: Depressed patients` scores were similar to AD in confrontation naming, concept definition, following commands, repetition and reading comprehension (sentence). Episodic memory and mental status subtests were useful in differentiating depressed patients from AD, a result that was reproduced when using analysis of covariance to control for the effect of age in the same subtests (p = 0.01 and 0.04, respectively). Conclusion: Language impairment resembling AD was found in the aforementioned language subtests of the ABCD in elderly depressed patients; the mental status and episodic memory subtests were useful to discriminate between AD and depression. The ABCD has proven to be a suitable tool for language evaluation in this population and should aid in the differentiation of AD and pseudodementia (as that of depression).

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Polymicrogyria (PMG) is a malformation of cortical development characterized by an excessive number of small gyri and abnormal cortical lamination, giving the cortical surface an irregular and gross appearance. The severity of clinical manifestations correlates with the extent of cortical involvement. The objective of the present study was to describe three families with linguistic features of developmental language disorder and reading impairment, and to establish a neuroanatomic correlation through neuroimaging. Subjects have been submitted to a comprehensive protocol including psychological assessment, language evaluation, neurological examination, and neuroimaging investigation. In our families, children usually had the diagnosis of developmental language disorder while adults had the diagnosis of reading impairment. MRI showed perisylvian polymicrogyria in several subjects of each family. Our data support the idea that there is a co-occurrence of developmental language disorder and reading impairment and both conditions may be associated with polymicrogyria. (c) 2007 Elsevier B.V. All rights reserved.

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In this paper, we will focus on the importance of languages as an asset to people and companies in knowledge-based society, giving special attention to the case of portuguese, not forgetting the role of Higher Education Institutions in preparing students to be part of the new creative multilingual and sucsessful class.