989 resultados para Middle facial third


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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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The two elcctrophysiological tests currently favoured in the clinical measurement of hearing threshold arc the brainstorm evoked potential (BAEP) and the slow vertex response (SVR). However, both tests possess disadvantages. The BAEP is the test of choice in younger patients as it is stable at all levels of arousal, but little information has been obtained to date at a range of frequencies. The SVR is frequency specific but is unreliable in certain adult subjects and is unstable during sleep or in young children. These deficiencies have prompted research into a third group of potentials, the middle latency response (MLR) and the 40HZ responses. This research has compared the SVR and 40HZ response in waking adults and reports that the 40HZ test can provide a viable alternative to the SVR provided that a high degree of subject relaxation is ensured. A second study examined the morphology of the MLR and 40HZ during sleep. This work suggested that these potentials arc markedly different during sleep and that methodological factors have been responsible for masking these changes in previous studies. The clinical possibilities of tone pip BAEPs were then examined as these components were proved to be the only stable responses present in sleep. It was found that threshold estimates to 5OOHz, lOOOHz and 4000Hz stimuli could be made to within 15dBSL in most cases. A final study looked more closely at methods of obtaining frequency specific information in sleeping subjects. Threshold estimates were made using established BAEP parameters and this was compared to a 40HZ procedure which recorded a series of BAEPs over a 100msec. time sweep. Results indicated that the 40mHz procedure was superior to existing techniques in estimating threshold to low frequency stimuli. This research has confirmed a role for the MLR and 40Hz response as alternative measures of hearing capability in waking subjects and proposes that the 40Hz technique is useful in measuring frequency specific thresholds although the responses recorded derive primarily from the brainstem.

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The tobacco industry's future depends on increasing tobacco use in low-income and middle-income countries (LMICs), which face a growing burden of tobacco-related disease, yet have potential to prevent full-scale escalation of this epidemic. To drive up sales the industry markets its products heavily, deliberately targeting non-smokers and keeps prices low until smoking and local economies are sufficiently established to drive prices and profits up. The industry systematically flaunts existing tobacco control legislation and works aggressively to prevent future policies using its resource advantage to present highly misleading economic arguments, rebrand political activities as corporate social responsibility, and establish and use third parties to make its arguments more palatable. Increasingly it is using domestic litigation and international arbitration to bully LMICs from implementing effective policies and hijacking the problem of tobacco smuggling for policy gain, attempting to put itself in control of an illegal trade in which there is overwhelming historical evidence of its complicity. Progress will not be realised until tobacco industry interference is actively addressed as outlined in Article 5.3 of the Framework Convention on Tobacco Control. Exemplar LMICs show this action can be achieved and indicate that exposing tobacco industry misconduct is an essential first step.

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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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The purpose of this study was to investigate the effects of cross-age peer writing response groups on the writing and reading achievement of third and fourth grade students. Students' attitudes about writing and their perceptions of themselves as writers were also measured at the end of the study. ^ One hundred and twenty-two third and fourth grade students enrolled in a public school in a middle-class, multi-cultural neighborhood participated in the study. Four existing classes of students were randomly assigned to either the experimental condition (EC) or the control condition (CC). Both groups were pretested and posttested for writing and reading achievement. The intervention, cross-age peer writing groups, met for eleven weeks. ^ Three hypotheses were examined in this study: (a) writing improvement score, (b) reading comprehension improvement score, and (c) students' attitudes toward writing and their perception of themselves as writers based on the five scales measured on the Writer Self-Perception Scale. ^ ANOVAs were done on the pretests and posttests for writing and the Stanford Achievement Test reading comprehension subtest scores for the year of the study and the previous year. ANOVAs were also done for the five areas of the Writer Self-Perception Scale. Cross-tabulations were also used to compare improvement level verses treatment group, and grade level. ^ Analysis of the data revealed that there was no evidence that the tutoring (EC) groups made more progress than the non-tutoring (CC) groups in writing and reading. There was evidence of growth in writing, especially by the fourth graders. Most importantly, the fourth grade tutors, the experimental group, had the most positive feelings about writing and themselves as writers. ^

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Many U.S. students do not perform well on mathematics assessments with respect to algebra topics such as linear functions, a building-block for other functions. Poor achievement of U.S. middle school students in this topic is a problem. U.S. eighth graders have had average mathematics scores on international comparison tests such as Third International Mathematics Science Study, later known as Trends in Mathematics and Science Study, (TIMSS)-1995, -99, -03, while Singapore students have had highest average scores. U.S. eighth grade average mathematics scores improved on TIMMS-2007 and held steady onTIMMS-2011. Results from national assessments, PISA 2009 and 2012 and National Assessment of Educational Progress of 2007, 2009, and 2013, showed a lack of proficiency in algebra. Results of curriculum studies involving nations in TIMSS suggest that elementary textbooks in high-scoring countries were different than elementary textbooks and middle grades texts were different with respect to general features in the U.S. The purpose of this study was to compare treatments of linear functions in Singapore and U.S. middle grades mathematics textbooks. Results revealed features currently in textbooks. Findings should be valuable to constituencies who wish to improve U.S. mathematics achievement. Portions of eight Singapore and nine U.S. middle school student texts pertaining to linear functions were compared with respect to 22 features in three categories: (a) background features, (b) general features of problems, and (c) specific characterizations of problem practices, problem-solving competency types, and transfer of representation. Features were coded using a codebook developed by the researcher. Tallies and percentages were reported. Welch's t-tests and chi-square tests were used, respectively, to determine whether texts differed significantly for the features and if codes were independent of country. U.S. and Singapore textbooks differed in page appearance and number of pages, problems, and images. Texts were similar in problem appearance. Differences in problems related to assessment of conceptual learning. U.S. texts contained more problems requiring (a) use of definitions, (b) single computation, (c) interpreting, and (d) multiple responses. These differences may stem from cultural differences seen in attitudes toward education. Future studies should focus on density of page, spiral approach, and multiple response problems.

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A cyclic marl-limestone succession of Middle-Late Campanian age has been investigated with respect to a Milankovitch-controlled origin of geochemical data. In general, the major element geochemistry of the marl-limestone rhythmites can be explained by a simple two-component mixing model with the end-members calcium carbonate and 'average shale'-like material. Carbonate content varies from 55 to 90%. Non-carbonate components are clay minerals (illite, smectite) and biogenic silica from sponge spicules, as well as authigenically formed zeolites (strontian heulandite) and quartz. The redox potential suggests oxidizing conditions throughout the section. Trace element and stable isotopic data as well as SEM investigations show that the carbonate mud is mostly composed of low-magnesium calcitic tests of planktic coccolithophorids and calcareous dinoflagellate cysts (calcispheres). Diagenetic overprint results in a decrease of 2% d18O and an increase in Mn of up to 250 ppm. However, the sediment seems to preserve most of its high Sr content compared to the primary low-magnesium calcite of co-occurring belemnite rostra. The periodicity of geochemical cycles is dominated by 413 ka and weak signals between 51 and 22.5 ka, attributable to orbital forcing. Accumulation rates within these cycles vary between 40 and 50 m/Ma. The resulting cyclic sedimentary sequence is the product of (a) changes in primary production of low-magnesium calcitic biogenic material in surface waters within the long eccentricity and the precession, demonstrated by the CaCO3 content and the Mg/Al, Mn/Al and Sr/Al ratios, and (b) fluctuations in climate and continental weathering, which changed the quality of supplied clay minerals (the illite/smectite ratio), demonstrated by the K/Al ratio. High carbonate productivity correlates with smectite-favouring weathering (semi-arid conditions, conspicuously dry and moist seasonal changes in warmer climates). Ti as the proxy indicator for the detrital terrigenous influx, as well as Rb, Si, Zr and Na, shows only low frequency signals, indicating nearly constant rates of supply throughout the more or less pure pelagic carbonate deposition of the long-lasting third-order Middle-Upper Campanian sedimentary cycle.

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Aims: Epidemiological evidence suggests that adipokines may be associated with the onset of type 2 diabetes, but the evidence to date is limited and inconclusive. This study examined the association between adiponectin and leptin and the subsequent diagnosis of type 2 diabetes in a UK population based cohort of non-diabetic middle-aged men.
Methods: Baseline serum levels of leptin and adiponectin were measured in 1839 nondiabetic men aged 50–60 years who were participating in the prospective populationbased PRIME study. Over a mean follow-up of 14.7 years, new cases of type 2 diabetes were determined from self-reported clinical information with subsequent validation by general practitioners.
Results: 151 Participants developed type 2 diabetes during follow-up. In Cox regression models adjusted for age, men in the top third of the leptin distribution were at increased risk (hazard ratio (HR) 4.27, 95% CI 2.67–6.83) and men in the top third of the adiponectin
distribution at reduced risk (HR 0.24, 95% CI 0.14–0.42) relative to men in the bottom third. However, significance was lost for leptin after additional adjustment for BMI, waist to hip ratio, lifestyle factors and biological risk factors, including C-reactive protein (CRP). Further adjustment for HOMA-IR also resulted in loss of significance for adiponectin.
Conclusions: This study provides evidence that adipokines are associated with men’s future type 2 diabetes risk but not independently of other risk factors.

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The goal of this thesis is twofold. Firstly, it investigates the actual, native use of spatial-deictic demonstratives in Japanese, Finnish and Swedish. Secondly, it investigates and elucidates the interlanguage of Finnish-speaking and Swedish-speaking learners of Japanese regarding their use of Japanese spatial-deictic demonstratives in the light of respective native use and, in comparison to the descriptions of demonstratives in the teaching materials used. Thus, the present study deals with analyses of two sets of empirical data: data produced by native-speaking informants (L1 data) and data produced by language learners (L2 data). These were elicited by Discourse Completion Tasks (DCTs) designed, collected and analyzed using both quantitative and qualitative methods by the author. The results showed that the actual use of demonstratives by the native informants was not always in accordance with the way described in grammars. The typological similarities between Japanese and Finnish were in this study not reflected in the native use of demonstratives, and some uses were not solely based on the spatial relations between the referent, the speaker and the addressee, but rather on social-interactional factors. The main findings regarding the learner data revealed some differences in the usage rate of the demonstratives between the two Finnish-speaking groups and the one Swedish-speaking learner group studied. There were, however, no particular differences found between them regarding the type of demonstrative used. It is suggested that these differences are first and foremost connected both with the teaching materials used and the more or less heterogeneous linguistic environment in which the learners reside, and only thereafter with the typological similarities or differences between their respective native languages, Finnish and Swedish, and the target language, Japanese. It is further argued that the learners’ use of the different Japanese demonstratives, that is the type of demonstrative used, could be explained in terms of familiarity with the grammar. That is, when the situations used in the DCTs were exemplified in teaching materials and were familiar to them, the learners seemed to use Japanese demonstratives as they are described in the teaching materials and as the native Japanese speakers use them. When the situations used in the DCTs were not exemplified in the teaching materials, the learners seem to rely more on their native language. The results, thus, suggest that the learners’ interlanguage is influenced by the grammar of the target language known to the learners, but also by the number of languages (or varieties) that the learners have contact with at the time of learning. The results of the present study have implications for the teaching of Japanese in at least two ways. Firstly, the importance of grammar instruction must be emphasized since its effect on the learners’ language is apparent. Secondly, the contents of teaching materials should be revised on the basis of the native speakers’ actual use of the grammar.

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Introdução: A parentalidade é um papel muito valorizado socialmente. No entanto, para casais com infertilidade o desempenho deste papel pode implicar tratamentos de fertilidade, alguns deles com recurso a gâmetas de dador. Para os casais que recorrem a gâmetas de dador, surge uma outra preocupação: contar à criança a origem da sua conceção ou manter segredo. Ainda que as motivações que influenciam este processo de decisão tenham sido alvo de estudo, em Portugal a investigação relativa a este tema é escassa. Objetivos: A presente investigação pretendeu desenvolver e estudar a validade facial do Questionário de Motivações para Revelar/Não Revelar a Parentalidade não Genética por Doação de Gâmetas (QMRDG), o qual se destina a avaliar as principais motivações que influenciam o processo de tomada de decisão dos pais que recorrem a gâmetas de dador relativamente a contar ou não contar ao/à seu/sua filho/a a origem da sua conceção. Pretendeu-se ainda explorar a relação entre os sintomas emocionais negativos e o sentido de competência parental nos diferentes grupos em estudo (pais que já contaram à criança, pais que decidiram não contar e pais que ainda não contaram). Metodologia: Estudo exploratório conduzido numa amostra de 21 participantes que recorrem a tratamento de fertilidade com recurso a gâmetas de dador, tendo tido filhos resultantes desse mesmo tratamento, com idades compreendidas entre os 30 e 49 anos. Os participantes preencheram um conjunto de questionários numa plataforma online, tendo o estudo sido divulgado pela Associação Portuguesa de Fertilidade. Resultados: Os dados obtidos indicam que a maioria dos pais ainda não contou ao/à seu/sua filho/a sua origem genética devido ao facto de a criança ser ainda muito pequena, encontrando-se estes com intenção de revelar à criança. Dos pais que já contaram, as motivações que mais influenciaram a decisão basearam-se na falta de motivos para omitir, na importância dada à honestidade, no direito do conhecimento das origens genéticas e na transparência no seio familiar. Face às motivações para não contar, das que mais influenciaram os pais salienta-se a pouca importância dada à genética. O QMRDG revelou possuir validade facial não tendo sido reportada a existência de itens ambíguos ou de difícil compreensão. Discussão: A tendência dos pais no presente estudo foi de contar ao/à seu/sua filho/a a origem da sua conceção, sendo também esta a tendência reportada em estudos mais recentes. Verificou-se a existência de algumas limitações no estudo, nomeadamente o tamanho da amostra. No entanto, o QMRDG mostrou possuir validade facial, podendo constituir-se como um instrumento útil na prática clínica e na investigação com pessoas que estejam a realizar tratamento de fertilidade com recurso a gâmetas de dador. / Introduction: Parenting is a highly valued social role. However, for couples dealing with infertility this role can involve fertility treatments, and for some of them donorassisted reproduction. For couples who use third party reproduction, another concern can emerge: tell the child about the donor conception, or preserve secrecy. Although arguments for decision making have been studied, in Portugal research on this topic is scanty. Objectives: The current study sought out to develop and study the facial validity of Motivations for Disclosing/Not Disclosing Non-genetic Parenthood through Gamete Donation (QMRDG), which is designed to assess motivations that influence the decision-making process of parents who use gamete donation regarding tell or not to tell to his/her son/daughter his/her conception. The existence of differences concerning emotional negative symptoms and parenting sense of competence in three groups (parents that already disclosed, parents that decided not to disclose and parents that did not decide what to do) was also explored. Methods: This exploratory study was conducted in sample of 21 participants who undergone third-party reproduction treatment and became parents. Participants´ age ranged from 30 to 49 years. Participants completed a set of questionnaires through an online platform. The study was advertised by Associação Portuguesa de Fertilidade. Results: Data showed that most parents did not disclose to their child their donor conception due to the fact that the child is still very young, but their intention seems to be to disclose in the future. For parents who have disclosed, core motivations for that decision are based on the lack of reasons for omitting, on the importance of honesty, on the right to know genetic origins and on transparency in the family. Concerning motivations for not disclosing the little importance given to genetics emerges as one of the most important ones. QMRDG revealed good facial validity. The existence of ambiguous or difficult to understand items has not been reported. Discussion: In our study parent’s tendency was to disclose to his/her son/daughter his/her donor conception and this is also the trend reported in recent studies. There are some methodological limitations that should be considered mainly due to the sample size. However, the QMRDG proved to be an instrument showing facial validity, and it can be a useful tool in clinical practice and research with people who are pursuing fertility treatment with gamete donation.

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Introduction Prediction of soft tissue changes following orthognathic surgery has been frequently attempted in the past decades. It has gradually progressed from the classic “cut and paste” of photographs to the computer assisted 2D surgical prediction planning; and finally, comprehensive 3D surgical planning was introduced to help surgeons and patients to decide on the magnitude and direction of surgical movements as well as the type of surgery to be considered for the correction of facial dysmorphology. A wealth of experience was gained and numerous published literature is available which has augmented the knowledge of facial soft tissue behaviour and helped to improve the ability to closely simulate facial changes following orthognathic surgery. This was particularly noticed following the introduction of the three dimensional imaging into the medical research and clinical applications. Several approaches have been considered to mathematically predict soft tissue changes in three dimensions, following orthognathic surgery. The most common are the Finite element model and Mass tensor Model. These were developed into software packages which are currently used in clinical practice. In general, these methods produce an acceptable level of prediction accuracy of soft tissue changes following orthognathic surgery. Studies, however, have shown a limited prediction accuracy at specific regions of the face, in particular the areas around the lips. Aims The aim of this project is to conduct a comprehensive assessment of hard and soft tissue changes following orthognathic surgery and introduce a new method for prediction of facial soft tissue changes.   Methodology The study was carried out on the pre- and post-operative CBCT images of 100 patients who received their orthognathic surgery treatment at Glasgow dental hospital and school, Glasgow, UK. Three groups of patients were included in the analysis; patients who underwent Le Fort I maxillary advancement surgery; bilateral sagittal split mandibular advancement surgery or bimaxillary advancement surgery. A generic facial mesh was used to standardise the information obtained from individual patient’s facial image and Principal component analysis (PCA) was applied to interpolate the correlations between the skeletal surgical displacement and the resultant soft tissue changes. The identified relationship between hard tissue and soft tissue was then applied on a new set of preoperative 3D facial images and the predicted results were compared to the actual surgical changes measured from their post-operative 3D facial images. A set of validation studies was conducted. To include: • Comparison between voxel based registration and surface registration to analyse changes following orthognathic surgery. The results showed there was no statistically significant difference between the two methods. Voxel based registration, however, showed more reliability as it preserved the link between the soft tissue and skeletal structures of the face during the image registration process. Accordingly, voxel based registration was the method of choice for superimposition of the pre- and post-operative images. The result of this study was published in a refereed journal. • Direct DICOM slice landmarking; a novel technique to quantify the direction and magnitude of skeletal surgical movements. This method represents a new approach to quantify maxillary and mandibular surgical displacement in three dimensions. The technique includes measuring the distance of corresponding landmarks digitized directly on DICOM image slices in relation to three dimensional reference planes. The accuracy of the measurements was assessed against a set of “gold standard” measurements extracted from simulated model surgery. The results confirmed the accuracy of the method within 0.34mm. Therefore, the method was applied in this study. The results of this validation were published in a peer refereed journal. • The use of a generic mesh to assess soft tissue changes using stereophotogrammetry. The generic facial mesh played a major role in the soft tissue dense correspondence analysis. The conformed generic mesh represented the geometrical information of the individual’s facial mesh on which it was conformed (elastically deformed). Therefore, the accuracy of generic mesh conformation is essential to guarantee an accurate replica of the individual facial characteristics. The results showed an acceptable overall mean error of the conformation of generic mesh 1 mm. The results of this study were accepted for publication in peer refereed scientific journal. Skeletal tissue analysis was performed using the validated “Direct DICOM slices landmarking method” while soft tissue analysis was performed using Dense correspondence analysis. The analysis of soft tissue was novel and produced a comprehensive description of facial changes in response to orthognathic surgery. The results were accepted for publication in a refereed scientific Journal. The main soft tissue changes associated with Le Fort I were advancement at the midface region combined with widening of the paranasal, upper lip and nostrils. Minor changes were noticed at the tip of the nose and oral commissures. The main soft tissue changes associated with mandibular advancement surgery were advancement and downward displacement of the chin and lower lip regions, limited widening of the lower lip and slight reversion of the lower lip vermilion combined with minimal backward displacement of the upper lip were recorded. Minimal changes were observed on the oral commissures. The main soft tissue changes associated with bimaxillary advancement surgery were generalized advancement of the middle and lower thirds of the face combined with widening of the paranasal, upper lip and nostrils regions. In Le Fort I cases, the correlation between the changes of the facial soft tissue and the skeletal surgical movements was assessed using PCA. A statistical method known as ’Leave one out cross validation’ was applied on the 30 cases which had Le Fort I osteotomy surgical procedure to effectively utilize the data for the prediction algorithm. The prediction accuracy of soft tissue changes showed a mean error ranging between (0.0006mm±0.582) at the nose region to (-0.0316mm±2.1996) at the various facial regions.

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Ischemic stroke is a major public health problem worldwide, considered as the third most costly health condition in developed countries, with urgent reperfusion remaining the paramount goal for its treatment. In line with the results of recent randomized control trials, the introduction of stent retrievers was a major advancement in the treatment of stroke; however, interventionalists sometimes encounter thrombi not-retrievable by applying conventional techniques. In this article, we present a case treated by an innovative double-stent retrieval in Y-configuration that may potentially help other clinicians in similar situations.