922 resultados para Facial prosthesis
Resumo:
For a series of six-coordinate Ru(II)(CO)L or Rh(III)(X–)L porphyrins which are facially differentiated by having a naphthoquinol- or hydroquinol-containing strap across one face, we show that ligand migration from one face to the other can occur under mild conditions, and that ligand site preference is dependent on the nature of L and X–. For bulky nitrogen-based ligands, the strap can be displaced sideways to accommodate the ligand on the same side as the strap. For the ligand pyrazine, we show 1 H NMR evidence for monodentate and bidentate binding modes on both faces, dependent on ligand concentration and metalloporphyrin structure, and that inter-facial migration is rapid under normal conditions. For monodentate substituted pyridine ligands there is a site dependence on structure, and we show clear evidence of dynamic ligand migration through a series of ligand exchange reactions.
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In this paper we propose a new method for face recognition using fractal codes. Fractal codes represent local contractive, affine transformations which when iteratively applied to range-domain pairs in an arbitrary initial image result in a fixed point close to a given image. The transformation parameters such as brightness offset, contrast factor, orientation and the address of the corresponding domain for each range are used directly as features in our method. Features of an unknown face image are compared with those pre-computed for images in a database. There is no need to iterate, use fractal neighbor distances or fractal dimensions for comparison in the proposed method. This method is robust to scale change, frame size change and rotations as well as to some noise, facial expressions and blur distortion in the image
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Periprosthetic fractures are increasingly frequent. The fracture may be located over the shaft of the prosthesis, at its tip or below (21). The treatment of explosion fractures is difficult because the shaft blocks the application of implants, like screws, which need to penetrate the medullary cavity. The cerclage, as a simple periosteal loop, made of wire or more recently cable, does not only avoid the medullary cavity. Its centripetal mode of action is well suited for reducing and maintaining radially displaced fractures. Furthermore, the cerclage lends itself well for minimally invasive internal fixation. New insight challenges the disrepute of which the cerclage technology suffered for decades. The outcome of cerclage fixation benefits from an improved understanding of its technology, mechano-biology and periosteal blood supply. Preconceived and generally accepted opinions like "strangulation of blood supply" need to be re-examined. Recent mechanical evaluations (22) demonstrate that the wire application may be improved but cable is superior in hand- ling, maintenance of tension and strength. Beside the classical concepts of absolute and relative stability a defined stability condition needs consideration. It is typical for cerclage. Called "loose-lock stability" it specifies the situation where a loosened implant allows first unimpeded displacement changing abruptly into a locked fixation preventing further dislocation.
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The design of artificial intelligence in computer games is an important component of a player's game play experience. As games are becoming more life-like and interactive, the need for more realistic game AI will increase. This is particularly the case with respect to AI that simulates how human players act, behave and make decisions. The purpose of this research is to establish a model of player-like behavior that may be effectively used to inform the design of artificial intelligence to more accurately mimic a player's decision making process. The research uses a qualitative analysis of player opinions and reactions while playing a first person shooter video game, with recordings of their in game actions, speech and facial characteristics. The initial studies provide player data that has been used to design a model of how a player behaves.
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When compared with similar joint arthroplasties, the prognosis of Total Ankle Replacement (TAR) is not satisfactory although it shows promising results post surgery. To date, most models do not provide the full anatomical functionality and biomechanical range of motion of the healthy ankle joint. This has sparked additional research and evaluation of clinical outcomes in order to enhance ankle prosthesis design. However, the limited biomechanical data that exist in literature are based upon two-dimensional, discrete and outdated techniques1 and may be inaccurate. Since accurate force estimations are crucial to prosthesis design, a paper based on a new biomechanical modeling approach, providing three dimensional forces acting on the ankle joint and the surrounding tissues was published recently, but the identified forces were suspected of being under-estimated, while muscles were . The present paper reports an attempt to improve the accuracy of the analysis by means of novel methods for kinematic processing of gait data, provided in release 4.1 of the AnyBody Modeling System (AnyBody Technology, Aalborg, Denmark) Results from the new method are shown and remaining issues are discussed.
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Facial expression is one of the main issues of face recognition in uncontrolled environments. In this paper, we apply the probabilistic linear discriminant analysis (PLDA) method to recognize faces across expressions. Several PLDA approaches are tested and cross-evaluated on the Cohn-Kanade and JAFFE databases. With less samples per gallery subject, high recognition rates comparable to previous works have been achieved indicating the robustness of the approaches. Among the approaches, the mixture of PLDAs has demonstrated better performances. The experimental results also indicate that facial regions around the cheeks, eyes, and eyebrows are more discriminative than regions around the mouth, jaw, chin, and nose.
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Background The risk factors and co-factors for sporadic childhood BL are unknown. We investigated demographic and age-specific characteristics of childhood BL (0–14 years) in the U.S. Procedure BL age-standardized incidence rates (2000 U.S. standard population), were calculated using data obtained from 12 registries in the NCI’s Surveillance, Epidemiology, and End Results program for cases diagnosed from 1992 through 2005. Incidence rate ratios and 95% confidence intervals (95% CI) were calculated by gender, age-group, race, ethnicity, calendar-year period, and registry. Results Of 296 cases identified, 56% were diagnosed in lymph nodes, 21% in abdominal organs, not including retroperitoneal lymph nodes, 14% were Burkitt cell leukemia, and 9% on face/head structures. The male-to-female case ratio was highest for facial/head tumors (25:1) and lowest for Burkitt cell leukemia (1.6:1). BL incidence rate was 2.5 (95% CI 2.3–2.8) cases per million person-years and was higher among boys than girls (3.9 vs. 1.1, p<0.001) and higher among Whites and Asians/Pacific Islanders than among Blacks (2.8 and 2.9 vs.1.2, respectively, p<0.001). By ethnicity, BL incidence was higher among non-Hispanic Whites than Hispanic Whites (3.2 vs. 2.0, p=0.002). Age-specific incidence rate for BL peaked by age 3–5 years (3.4 cases per million), then stabilized or declined with increasing age, but it did not vary with calendar-year or registry area. Conclusions Our results indicate that early childhood exposures, male-sex, and White race may be risk factors for sporadic childhood BL in the United States. Keywords: epidemiology, pediatric cancer, non-Hodgkin lymphoma, HIV/AIDS
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Endemic Burkitt lymphoma (BL) is etiologically associated with Epstein-Barr virus (EBV) and ecologically linked to Plasmodium falciparum malaria. However, these infections imperfectly correlate with BL epidemiology. To obtain recent epidemiological data, we studied district- and county-specific BL incidence and standardized incidence ratios using data collected from 1997 through 2006 at Lacor Hospital in northern Uganda, where studies were last done more than 30 years ago. Among 500 patients, median age was 6 years (inter-quartile range 5-8) and male-to-female ratio was 1.8:1. Among those known, most presented with abdominal (56%, M: F 1.4:1) vs. only facial tumors (35%, M: F 3.0:1). Abdominal tumors occurred in older (mean age: 7.0 vs. 6.0 years; p<0.001) and more frequently in female children (68% vs. 50%; OR 2.2, 95% CI 1.5-3.5). The age-standardized incidence was 2.4 per 100,000, being 0.6 in 1-4 year olds, 4.1 in 5-9 year olds and 2.8 in 10-14 year olds and varied 3-4-fold across districts. The incidence was lower in districts that were far from Lacor and higher in districts that were close to Lacor. While districts close to Lacor were also more urbanized, the incidence was higher in the nearby perirural areas. We highlight high BL incidence and geographic variation in neighboring districts in northern Uganda. While distance from Lacor clearly influenced the patterns, the incidence was lower in municipal than in surrounding rural areas. Jaw tumors were characterized by young age and male gender, but presentation has shifted away from facial to mostly abdominal. Keywords: Africa, cancer, malaria, Epstein-Barr virus, clustering, epidemiology
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We examine methodologies and methods that apply to multi-level research in the learning sciences. In so doing we describe how multiple theoretical frameworks informs the use of different methods that apply to social levels involving space-time relationships that are not accessible consciously as social life is enacted. Most of the methods involve analyses of video and audio files. Within a framework of interpretive research we present a methodology of event-oriented social science, which employs video ethnography, narrative, conversation analysis, prosody analysis, and facial expression analysis. We illustrate multi-method research in an examination of the role of emotions in teaching and learning. Conversation and prosody analyses augment facial expression analysis and ethnography. We conclude with an exploration of ways in which multi-level studies can be complemented with neural level analyses.
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The Exeter stems vary in length from 90 to 150 mm. The shorter stems generally have lower offsets. The purpose of this study was to determine if length of stem, with fixed offset, affected rotational stability. Mechanical testing was carried out on 10 implant-cement constructs with 2 loading profiles, rising from chair and stair climbing, at different simulated implant lengths using purpose-built apparatus. This paper presents a mechanism for clinically observed rotational stability and explains the mechanical characteristics required for rotational stability in Exeter femoral stems. © 2012.
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Summary: Objective: We performed spike triggered functional MRI (fMRI) in a 12 year old girl with Benign Epilepsy with Centro-temporal Spikes (BECTS) and left-sided spikes. Our aim was to demonstrate the cerebral origin of her interictal spikes. Methods: EEG was recorded within the 3 Tesla MRI. Whole brain fMRI images were acquired, beginning 2–3 seconds after spikes. Baseline fMRI images were acquired when there were no spikes for 20 seconds. Image sets were compared with the Student's t-test. Results: Ten spike and 20 baseline brain volumes were analysed. Focal activiation was seen in the inferior left sensorimotor cortex near the face area. The anterior cingulate was more active during baseline than spikes. Conclusions: Left sided epileptiform activity in this patient with BECTS is associated with fMRI activation in the left face region of the somatosensory cortex, which would be consistent with the facial sensorimotor involvement in BECT seizures. The presence of BOLD signal change in other regions raises the possibility that the scalp recorded field of this patient with BECTs may reflect electrical change in more than one brain region.
In the pursuit of effective affective computing : the relationship between features and registration
Resumo:
For facial expression recognition systems to be applicable in the real world, they need to be able to detect and track a previously unseen person's face and its facial movements accurately in realistic environments. A highly plausible solution involves performing a "dense" form of alignment, where 60-70 fiducial facial points are tracked with high accuracy. The problem is that, in practice, this type of dense alignment had so far been impossible to achieve in a generic sense, mainly due to poor reliability and robustness. Instead, many expression detection methods have opted for a "coarse" form of face alignment, followed by an application of a biologically inspired appearance descriptor such as the histogram of oriented gradients or Gabor magnitudes. Encouragingly, recent advances to a number of dense alignment algorithms have demonstrated both high reliability and accuracy for unseen subjects [e.g., constrained local models (CLMs)]. This begs the question: Aside from countering against illumination variation, what do these appearance descriptors do that standard pixel representations do not? In this paper, we show that, when close to perfect alignment is obtained, there is no real benefit in employing these different appearance-based representations (under consistent illumination conditions). In fact, when misalignment does occur, we show that these appearance descriptors do work well by encoding robustness to alignment error. For this work, we compared two popular methods for dense alignment-subject-dependent active appearance models versus subject-independent CLMs-on the task of action-unit detection. These comparisons were conducted through a battery of experiments across various publicly available data sets (i.e., CK+, Pain, M3, and GEMEP-FERA). We also report our performance in the recent 2011 Facial Expression Recognition and Analysis Challenge for the subject-independent task.
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This study determined the rate and indication for revision between cemented, uncemented, hybrid and resurfacing groups from NJR (6 th edition) data. Data validity was determined by interrogating for episodes of misclassification. We identified 6,034 (2.7%) misclassified episodes, containing 97 (4.3%) revisions. Kaplan-Meier revision rates at 3 years were 0.9% cemented, 1.9% for uncemented, 1.2% for hybrids and 3.0% for resurfacings (significant difference across all groups, p<0.001, with identical pattern in patients <55 years). Regression analysis indicated both prosthesis group and age significantly influenced failure (p<0.001). Revision for pain, aseptic loosening, and malalignment were highest in uncemented and resurfacing arthroplasty. Revision for dislocation was highest in uncemented hips (significant difference between groups, p<0.001). Feedback to the NJR on data misclassification has been made for future analysis. © 2012 Wichtig Editore.
Resumo:
Articular cartilage is a highly resilient tissue located at the ends of long bones. It has a zonal structure, which has functional significance in load-bearing. Cartilage does not spontaneously heal itself when damaged, and untreated cartilage lesions or age-related wear often lead to osteoarthritis (OA). OA is a degenerative condition that is highly prevalent, age-associated, and significantly affects patient mobility and quality of life. There is no cure for OA, and patients usually resort to replacing the biological joint with an artificial prosthesis. An alternative approach is to dynamically regenerate damaged or diseased cartilage through cartilage tissue engineering, where cells, materials, and stimuli are combined to form new cartilage. However, despite extensive research, major limitations remain that have prevented the wide-spread application of tissue-engineered cartilage. Critically, there is a dearth of information on whether autologous chondrocytes obtained from OA patients can be used to successfully generate cartilage tissues with structural hierarchy typically found in normal articular cartilage. I aim to address these limitations in this thesis by showing that chondrocyte subpopulations isolated from macroscopically normal areas of the cartilage can be used to engineer stratified cartilage tissues and that compressive loading plays an important role in zone-dependent biosynthesis of these chondrocytes. I first demonstrate that chondrocyte subpopulations from the superficial (S) and middle/deep (MD) zones of OA cartilage are responsive to compressive stimulation in vitro, and that the effect of compression on construct quality is zone-dependent. I also show that compressive stimulation can influence pericelluar matrix production, matrix metalloproteinase secretion, and cytokine expression in zonal chondrocytes in an alginate hydrogel model. Subsequently, I focus on recreating the zonal structure by forming layered constructs using the alginate-released chondrocyte (ARC) method either with or without polymeric scaffolds. Resulting zonal ARC constructs had hyaline morphology, and expressed cartilage matrix molecules such as proteoglycans and collagen type II in both scaffold-free and scaffold-based approaches. Overall, my findings demonstrate that chondrocyte subpopulations obtained from OA joints respond sensitively to compressive stimulation, and are able to form cartilaginous constructs with stratified organization similar to native cartilage using the scaffold-free and scaffold-based ARC technique. The ultimate goal in tissue engineering is to help provide improved treatment options for patients suffering from debilitating conditions such as OA. Further investigations in developing functional cartilage replacement tissues using autologous chondrocytes will bring us a step closer to improving the quality of life for millions of OA patients worldwide.
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The foetal alcohol syndrome (FAS) was first identified as a syndrome in 1973. Since then a large body of research has accumulated. The full syndrome in which heavy alcohol use in pregnancy results in growth retardation, a characteristic facial dysmorphology and brain damage will be described. FAS is the commonest preventable, known cause of intellectual handicap, however, a large proportion of people with partial foetal alcohol syndrome have an intelligence in the normal range. Those with the full syndrome and with identified and diagnosed, intellectual handicap are more likely to receive appropriate services. Those with an intelligence in the normal range, suffer from severe psycho- social disabilities resulting in homelessness, mental illness and frequently criminality. There is a larger number of people with a partial syndrome who also suffer from high rates of secondary disability including learning problems and 70% of FAS people also have ADD or ADHD...