581 resultados para Lingual retainer
Resumo:
In recent years, Twitter has become one of the most important microblogging services of the Web 2.0. Among the possible uses it allows, it can be employed for communicating and broadcasting information in real time. The goal of this research is to analyze the task of automatic tweet generation from a text summarization perspective in the context of the journalism genre. To achieve this, different state-of-the-art summarizers are selected and employed for producing multi-lingual tweets in two languages (English and Spanish). A wide experimental framework is proposed, comprising the creation of a new corpus, the generation of the automatic tweets, and their assessment through a quantitative and a qualitative evaluation, where informativeness, indicativeness and interest are key criteria that should be ensured in the proposed context. From the results obtained, it was observed that although the original tweets were considered as model tweets with respect to their informativeness, they were not among the most interesting ones from a human viewpoint. Therefore, relying only on these tweets may not be the ideal way to communicate news through Twitter, especially if a more personalized and catchy way of reporting news wants to be performed. In contrast, we showed that recent text summarization techniques may be more appropriate, reflecting a balance between indicativeness and interest, even if their content was different from the tweets delivered by the news providers.
Resumo:
Usinig original data on 1,5000 mandibles, but mainly previously published data, I present a overview of the distribution characteristics of mandibular torus and a hypothesis concerning its cause. Pedigree studies have established that genetic factors influence torus development. Extrinsic factors are strongly implicated by other evidence: prevalence among Arctic peoples, effect of dietary change, age regression, preponderance in males and on the right side, effect of cranial deformation, concurrence with palatine torus and maxillary alveolar exostoses, and clinical evidence. I propose that the primary factor is masticatory stress. According to a mechanism suggested by orthodontic research, the horizontal component of bite force tips the lower canine, premolars and first molar so that their root apices exert pressure on the periodontal membrane, causing formation of new bone on the lingual cortical plate of the alveolar process. Thus formed, the hyperostosis is vulnerable to trauma and its periosteal covering becomes bruised causing additional deposition of bone. Genes influence torus indirectly through their effect on occlusion. A patern of increased expressivity with incidence suggests that a quasicontinuous model may provide a better fit to pedigree data than single locus models previously tested.
Resumo:
Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz
Resumo:
Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz
Resumo:
Includes index.
Resumo:
Primary Objective. To extend the capabilities of current electropalatography (EPG) systems by developing a pressure-sensing EPG system. An initial trial of a prototype pressure-sensing palate will be presented. Research Design. The processes involved in designing the pressure sensors are outlined, with Hall effect transistors being selected. These units are compact, offer high sensitivity and are inexpensive. An initial prototype acrylic palate was constructed with five embedded pressure sensors. Syllable repetitions were recorded from one adult female. Main Outcomes, Results and Future Directions. The pressure-sensing palate was capable of recording dynamic tongue-to-palate pressures, with minimal to no interference to speech detected perceptually. With a restricted number of sensors, problems were encountered in optimally positioning the sensors to detect the consonant lingual pressures. Further developments are planned for various aspects of the pressure-sensing system. Conclusions. Although only in the prototype stage, the pressure-sensing palate represents the new generation of EPG. Comprehensive analysis of tongue-to-palate contacts, including pressure measures, is expected to enable more specific and effective therapeutic techniques to be developed for a variety of speech disorders.
Resumo:
Cementum is known to be growth-hormone (GH)-responsive, but to what extent is unclear. This study examines the effects of extremes of GH status on cementogenesis in three lines of genetically modified mice; GH excess (giant), GH antagonist excess (dwarf), and GH receptor-deleted (GHR-KO) (dwarf). Age-matched mandibular molar tissues were processed for light microscope histology. Digital images of sections of first molar teeth were captured for morphometric analysis of lingual root cementum. Cross-sectional area of the cellular cementum was a sensitive guide to GH status, being reduced nearly 10-fold in GHR-KO mice, three-fold in GH antagonist mice, and increased almost two-fold in giant mice (p
Resumo:
The present study employed electropalatography (EPG) and a nonspeech measure of lingual function to examine, in detail, the articulatory production deficits of two individuals with Parkinson disease (PD) and hypokinetic dysarthria. Participants read 10 repetitions of CV words contained within the carrier phrase I saw a _ today while wearing an EPG artificial palate. Target consonants included the alveolar stop /t/, lateral approximant /l/, and the alveolar fricative /s/ in the /a/ vowel environment. The results of the two participants were compared to an age-matched control group. Examination of the perceptual features of articulatory production, lingual strength, fine force control and endurance, tongue-palate contact patterns, and segment durations were conducted. Results of the study revealed quite different articulatory deficits in the two participants. Specifically, the articulation of Participant One (P1) was characterized by a fast rate of speech, undershooting of articulatory targets, and reduced duration of consonant closures. In contrast, Participant Two (P2) demonstrated tongue-palate contact patterns indicative of impaired lingual control in the presence of both normal and increased articulatory segment durations. Potential reasons for the differing articulatory deficits were hypothesized. The current study demonstrated that assessment with EPG identified potential causes of consonant imprecision in two individuals with hypokinetic dysarthria. Directions for speech pathology intervention, salient from the results of the study, were also noted.
Resumo:
Electropalatography (EPG) was used as a biofeedback tool in a case study of a 30-year-old male with disordered articulation following traumatic brain injury (TBI). Based on qualitative measures of the participant's intelligibility, improved articulation of the fricatives /s/ and /integral/ were selected as treatment targets. Therapy was administered three times a week for 5 weeks. Results showed that word and sentence intelligibility increased approximately 10%, and error patterns for lingual articulation indicated that fricative -> stop and other fricative errors decreased considerably. EPG measures for /s/ exhibited a significantly more anterior main focus of articulatory contact post therapy. Consonant durations were significantly longer during weeks 3 and 4, and this finding was associated with the emergence of an articulatory contact pattern with a groove rather than complete closure. This articulatory pattern appeared inconsistently and was found to vary across articulations of /s/ but also within a single consonant production. For /integral/, the amount of contact was significantly reduced post therapy and an increase in duration was noted during week 4, similar to that occurring in the production of /s/. Spatial and timing measures were more variable than in normal speakers of English and indicated a general increase in variability across weeks for both /s/ and /integral/. It was concluded that, although the correct fricative patterns appeared only intermittently during production of the consonants, there seemed to be sufficient information for the listener to be able to classify the sound as a fricative. As a part of an intervention program, visual EPG biofeedback therapy would appear to have a definite role in assisting dysarthric speakers exhibiting difficulties with lingual articulation in understanding their errors, learning how to exploit kinesthetic, and acoustic sources of feedback, and how to make appropriate adjustments in tongue articulation to increase the level of speech intelligibility.
Resumo:
The morphology and functional occlusion of the cheekteeth of 57 dugongs Dugong dugon of both sexes were examined using reflected light and scanning electron microscopy, radiography, hardness testing and skull manipulation. The functional morphology of the horny oral pads was also described. Mouthparts and body size allometry was examined for ontogenetic and gender-related trends. We found that the worn erupted cheekteeth of the dugong are simple flat pegs composed of soft degenerative dentine. During occlusion, the mandible moves in a mainly antero-lingual direction, with the possibility of mandibular retraction in some individuals. Anterior parts of the cheektooth row may become non-functional as a dugong ages. As a function of body size, dugong cheekteeth are extremely small compared with those of other mammalian herbivores, and with other hindgut fermenters in particular. The morphology, small size and occlusal variability of the cheekteeth suggest that there has not been strong selective pressure acting to maintain an effective dentition. In contrast, great development of the horny pads and associated skull parameters and their lower size variability suggest that the horny pads may have assumed the major role in food comminution.
Resumo:
Document classification is a supervised machine learning process, where predefined category labels are assigned to documents based on the hypothesis derived from training set of labelled documents. Documents cannot be directly interpreted by a computer system unless they have been modelled as a collection of computable features. Rogati and Yang [M. Rogati and Y. Yang, Resource selection for domain-specific cross-lingual IR, in SIGIR 2004: Proceedings of the 27th annual international conference on Research and Development in Information Retrieval, ACM Press, Sheffied: United Kingdom, pp. 154-161.] pointed out that the effectiveness of document classification system may vary in different domains. This implies that the quality of document model contributes to the effectiveness of document classification. Conventionally, model evaluation is accomplished by comparing the effectiveness scores of classifiers on model candidates. However, this kind of evaluation methods may encounter either under-fitting or over-fitting problems, because the effectiveness scores are restricted by the learning capacities of classifiers. We propose a model fitness evaluation method to determine whether a model is sufficient to distinguish positive and negative instances while still competent to provide satisfactory effectiveness with a small feature subset. Our experiments demonstrated how the fitness of models are assessed. The results of our work contribute to the researches of feature selection, dimensionality reduction and document classification.
Resumo:
Previous studies have indicated that consonant imprecision in Parkinson's disease (PD) may result from a reduction in the amplitude of lingual movements or articulatory undershoot. While this has been postulated, direct measurement of the tongue's contact with the hard palate during speech production has not been undertaken. Therefore, the present study aimed to use electropalatography (EPG) to determine the exact nature of tongue-palate contact in a group of individuals with PD and consonant imprecision (n=9). Furthermore, the current investigation also aimed to compare the results of the participants with PD to a group of aged (n=7) and young (n=8) control speakers to determine the relative contribution of ageing of the lingual musculature to any articulatory deficits noted. Participants were required to read aloud the phrase 'I saw a ___ today' with the artificial palate in-situ. Target words included the consonants /l/, /s/ and /t/ in initial position in both the /i/ and /a/ vowel environments. Phonetic transcription of phoneme productions and description of error types was completed. Furthermore, representative frames of contact were employed to describe the features of tongue-palate contact and to calculate spatial palatal indices. Results of the perceptual investigation revealed that perceived undershooting of articulatory targets distinguished the participant group with PD from the control groups. However, objective EPG assessment indicated that undershooting of the target consonant was not the cause of the perceived articulatory errors. It is, therefore, possible that reduced pressure of tongue contact with the hard palate, sub-lingual deficits or impaired articulatory timing resulted in the perceived undershooting of the target consonants.
Resumo:
Previous investigations employing electropalatography (EPG) have identified articulatory timing deficits in individuals with acquired dysarthria. However, this technology is yet to be applied to the articulatory timing disturbance present in Parkinson's disease (PD). As a result, the current investigation aimed to use EPG to comprehensively examine the temporal aspects of articulation in a group of nine individuals with PD at sentence, word and segment level. This investigation followed on from a prior study (McAuliffe, Ward and Murdoch) and similarly, aimed to compare the results of the participants with PD to a group of aged (n=7) and young controls (n=8) to determine if ageing contributed to any articulatory timing deficits observed. Participants were required to read aloud the phrase I saw a ___ today'' with the EPG palate in-situ. Target words included the consonants /1/, /s/ and /t/ in initial position in both the /i/ and /a/ vowel environments. Perceptual investigation of speech rate was conducted in addition to objective measurement of sentence, word and segment duration. Segment durations included the total segment length and duration of the approach, closure/constriction and release phases of EPG consonant production. Results of the present study revealed impaired speech rate, perceptually, in the group with PD. However, this was not confirmed objectively. Electropalatographic investigation of segment durations indicated that, in general, the group with PD demonstrated segment durations consistent with the control groups. Only one significant difference was noted, with the group with PD exhibiting significantly increased duration of the release phase for /1a/ when compared to both the control groups. It is, therefore, possible that EPG failed to detect lingual movement impairment as it does not measure the complete tongue movement towards and away from the hard palate. Furthermore, the contribution of individual variation to the present findings should not be overlooked.
Resumo:
O objetivo do presente estudo consistiu em avaliar as alterações dentoesqueléticas e tegumentares promovidas pelo tratamento ortodôntico fixo com a retração anterior em duas fases, por meio de telerradiografias em norma lateral. Foram selecionados 14 pacientes com idade média de 14,6 anos que necessitavam de extrações dos quatro primeiros pré-molares, todos apresentando má oclusão de Classe I. A retração anterior foi realizada inicialmente pela retração dos caninos (previamente à colagem dos incisivos) e subsequentemente, pelos incisivos. Doze pacientes não utilizaram qualquer dispositivo para ancoragem e dois pacientes utilizaram como ancoragem o Arco Extra-Bucal (AEB) de uso noturno. Foram avaliadas as telerradiografias em norma lateral ao início, final da retração dos caninos e final de tratamento ortodôntico fixo. As telerradiografias foram escaneadas e mensuradas por meio do programa Radiocef® (RadiomemoryR- Belo Horizonte, Brasil). Os dados foram submetidos à Análise de Variância e teste de Tukey (p<0,05). Os resultados demonstraram poucas alterações esqueléticas, exceto por uma retrusão suave do ponto A e aumento do comprimento mandibular, da altura facial ântero-inferior e total e rotação suave anti-horária mandibular devido ao crescimento craniofacial. Após a retração dos caninos, houve uma inclinação para lingual e retrusão dos incisivos superiores e inferiores, que permaneceram estáveis para os incisivos superiores no período final de tratamento. Já os incisivos inferiores neste mesmo período, retruíram mais com uma inclinação semelhante àquela inicial. Além disso, não houve perda de ancoragem de forma estatisticamente significante. Estas alterações dentárias refletiram em retrusão dos lábios superior e inferior após a retração dos caninos, sendo que o lábio inferior continuou a retrair no período final de tratamento. Conclui-se que o tratamento com a retração em duas fases não representou perda de ancoragem estatisticamente significante, além de diminuir a convexidade facial.
Resumo:
O presente trabalho tem o objetivo de verificar as angulações e as inclinações dentárias obtidas no final do tratamento ortodôntico, em casos tratados com aparelho ortodôntico fixo e prescrição MBT e compará-las com os valores encontrados por Andrews para a oclusão normal natural. Foram utilizados 30 pares de modelos de gesso finais, de 30 pacientes, tratados, na faixa etária de 13 a 23 anos. Como pré-requisitos, estes pacientes não deveriam ter sido submetidos a qualquer tipo de intervenção ortopédica, uso de elásticos intermaxilares, compensações dento-alveolares e tratamentos realizados com extração. Para a mensuração da angulação mésio-distal e da inclinação vestíbulo-lingual utilizou-se um dispositivo, desenvolvido em pesquisa anterior, capaz de realizar tais medições. De acordo com a metodologia empregada e diante dos resultados obtidos, pôde-se concluir que as angulações das coroas dentárias tanto superiores quanto inferiores apresentaram valores positivos. Quanto às inclinações das coroas dentárias, em ambos os arcos dentários, foram encontrados valores positivos para os incisivos centrais e laterais, ao passo que caninos, pré-molares e primeiros molares apresentaram valore s negativos. Variações individuais estiveram presentes nas duas mensurações realizadas. Ao comparar nossos resultados com os de Andrews, obtivemos diferenças estatisticamente significantes para a maioria dos dentes, em ambas as medidas efetuadas.