An Open Source Testing Tool for Evaluating Handwriting Input Methods

This paper presents an open source tool for testing the recognition accuracy of Chinese handwriting input methods. The tool consists of two modules, namely the PC and Android mobile client. The PC client reads handwritten samples in the computer, and transfers them individually to the Android client in accordance with the socket communication protocol. After the Android client receives the data, it simulates the handwriting on screen of client device, and triggers the corresponding handwriting recognition method. The recognition accuracy is recorded by the Android client. We present the design principles and describe the implementation of the test platform. We construct several test datasets for evaluating different handwriting recognition systems, and conduct an objective and comprehensive test using six Chinese handwriting input methods with five datasets. The test results for the recognition accuracy are then compared and analyzed.Comment: 5 pages, 3 figures, 11 tables. Accepted to appear at ICDAR 201

Head-to-head comparison of amplified plasmonic exosome Aβ42 platform and single-molecule array immunoassay in a memory clinic cohort

Background: Various blood biomarkers reflecting brain amyloid‐β (Aβ) load have recently been proposed with promising results. However, to date, no comparative study among blood biomarkers has been reported. Our objective is to examine the diagnostic performance and cost effectiveness of three blood biomarkers on the same cohort. Methods: Using the same cohort (n=68), we compared the performance of the single‐molecule array (Simoa)‐Aβ40 and Aβ42, Aβ42/Aβ40 and the amplified plasmonic exosome (APEX)‐Aβ42 blood biomarkers using amyloid PET as the reference standard. We also determined the extent to which these blood tests can reduce the recruitment cost of clinical trials by identifying Amyloid positive (Aβ+) participants. Results: Compared to Simoa biomarkers, APEX‐Aβ42 showed significantly higher correlations with amyloid PET retention values and excellent diagnostic performance (sensitivity=100%, specificity=93.3%, AUC=0.995). When utilized for clinical trial recruitment, our simulation showed that pre‐screening with blood biomarkers followed by a confirmatory amyloid PET imaging would roughly half the cost (56.8% reduction for APEX‐Aβ42 and 48.6% for Simoa‐Aβ42/Aβ40) as compared to the situation where only PET imaging is used. Moreover, with a 100% sensitivity; APEX‐Aβ42 pre‐screening does not increase the required number of initial participants. Conclusions: With its high diagnostic performance, APEX is an ideal candidate for Aβ+ subject identification, monitoring, primary care screening, and could efficiently enrich clinical trials with Aβ+ participants while halving recruitment costs

Fabrication of Porous TiO2 Hollow Spheres and Their Application in Gas Sensing

In this work, porous TiO2 hollow spheres with an average diameter of 100 nm and shell thickness of 20 nm were synthesized by a facile hydrothermal method with NH4HCO3 as the structure-directing agent, and the formation mechanism for this porous hollow structure was proved to be the Ostwald ripening process by tracking the morphology of the products at different reaction stages. The product was characterized by SEM, TEM, XRD and BET analyses, and the results show that the as-synthesized products are anatase phase with a high surface area up to 132.5 m2/g. Gas-sensing investigation reveals that the product possesses sensitive response to methanal gas at 200°C due to its high surface area

Modélisation des vaisseaux basée sur l'imagerie spécifique au patient : Application à l'évaluation des pathologies de l'aorte thoracique

Cette thèse porte sur l’étude des propriétés mécaniques de la paroi de l’aorte dans le contexte des anévrismes thoraciques ascendants. Parmi les maladies cardiovasculaires, qui sont la première cause de décès, l’anévrisme de l’aorte thoracique ascendante (ATAA) est une pathologie majeure de l’aorte. L’ATAA est associé à un taux de morbidité et de mortalité élevé en cas d’événements aigus (rupture et/ou dissection). Mais l’épidémiologie des ATAA est difficile à étudier. Malgré les progrès des soins intensifs et de la chirurgie, la mortalité liée à l’intervention peut encore atteindre 25 %. La décision de procéder à une réparation chirurgicale de l’ATAA repose principalement sur la taille, la vitesse de croissance, les symptômes et les antécédents familiaux ou les troubles du tissu conjonctif. Ces paramètres principalement morphologiques sont de mauvais prédicteurs d’événements aigus. Du point de vue mécanique, l’hypothèse est que la rupture de l’anévrisme se produit lorsque la contrainte exercée sur la paroi dépasse la résistance de celle-ci. Par conséquent, l’évaluation des propriétés mécaniques de l’aorte peut aider à mieux stratifier les patients nécessitant une intervention et potentiellement améliorer l’évaluation du risque. L’objectif de ce travail est de développer une approche inverse pour la modélisation biomécanique de l’aorte à partir de données d’imagerie médicale, afin de quantifier régionalement les propriétés matérielles de l’aorte du patient et de calculer les cartes de contraintes. Après avoir présenté le contexte médical et biomécanique (chapitre 1), le chapitre 2 donne un aperçu des aspects méthodologiques de la modélisation par éléments finis directe et inverse des vaisseaux. Le flux de travail méthodologique que nous proposons est illustré sur un ensemble de données de patients. Dans le chapitre 3, nous fournissons une vue d’ensemble des concepts pertinents pour le développement de lois constitutives pour les matériaux renforcés par des fibres et en particulier la loi anisotrope HGO que nous avons sélectionnée pour la modélisation des tissus de l’aorte. L’implémentation de la loi HGO dans Abaqus est validée en utilisant un cylindre à paroi épaisse. La procédure de modélisation par éléments finis est décrite et étudiée au chapitre 4 sur des géométries synthétiques idéalisées et des géométries spécifiques au patient. Notamment, une étude de sensibilité des paramètres de la loi HGO sur les facteurs géométriques, la déformation et la contrainte est présentée et sera utilisée pour contrôler l’optimisation inverse. Enfin, l’approche de modélisation inverse pour l’estimation des paramètres du modèle spécifique au patient est présentée et discutée au chapitre 5 sur des cas synthétiques bien contrôlés. Nos premiers résultats à partir de données 3D-CT de patients sont présentés. Le rapport se termine par un résumé de nos principales contributions et conclusions, ainsi que par les perspectives de ce travail.This thesis is focused on the investigation of the mechanical properties of the aorta wall in the context of ascending thoracic aneurysms. Cardiovascular diseases are the leading cause of death worldwide (30% of total mortality). In the cardiovascular disease landscape, the ascending thoracic aorta aneurysm (ATAA) is one of the major pathologies of the aorta. ATAA is associated with a high morbidity and high mortality rate in case of acute events (rupture and/or dissection). But the epidemiology of ATAA is difficult to investigate because it is a clinically silent disease. Despite advances in intensive care and surgery, intervention related mortality is still as high as 25%. The decision for ATAA surgical repair is mostly based on size, speed of growth, symptoms and family history or connective tissue disorders. These mainly morphological parameters are poor predictors of acute events, i.e. dissection or rupture of the aortic wall. Functional parameters such as blood flow and mechanical properties of the arterial wall itself provide additional information that may aid the clinical decision making. Consequently, in the last decade, a direction in research has focused on the investigation of these mechanical parameters using finite element modeling (FEM). From the mechanical point of view, the hypothesis is that the rupture of aneurysm occurs when the wall stress exceeds the wall strength. Therefore, the evaluation of the aorta’s mechanical properties can help to better stratify patients in need of intervention and potentially improve risk assessment. The aim of the present work was to develop an inverse approach for patient-specific biomechanical aorta modeling from medical imaging data, in order to regionally quantify the material properties of patient’s aorta and compute the stress maps. After introducing the medical and the biomechanical context (Chapter 1), Chapter 2 provides an overview of the methodological aspects for forward and inverse FE Modeling of vessels. Our proposed methodological workflow is illustrated on one patient dataset. In chapter 3, we provide an overview of the concepts relevant to the development of constitutive laws for fiber-reinforced materials and in particular the anisotropic HGO law that we selected for aorta tissue modeling. The implementation of the HGO law within Abaqus is validated using a thick-wall cylinder. The forward FE modeling procedure is described and studied in Chapter 4 on both synthetic geometries and patient specific geometries. Notably, a sensitivity study of the HGO law parameters onto strain is presented and will be used to control the inverse optimization. Finally, the inverse modeling approach for the estimation of patient specific model’s parameters is introduced and discussed in Chapter 5. Our first results from patient 3D-CT data are presented. The report ends with a summary of our main contributions and findings, and the perspectives of this work

Resistant Starch-Based Edible Coating Composites for Spray-Dried Microencapsulation of Lactobacillus acidophilus, Comparative Assessment of Thermal Protection, In Vitro Digestion and Physicochemical Characteristics

Polysaccharides have excellent potential as food-grade coating materials for microencapsulation in pro- and prebiotics-based functional food industry. In this study, potato, maize, and rice resistant starches composite coatings with D-mannose, maltodextrin, and whey protein concentrate were prepared for the spray-dried microencapsulation of Lactobacillus acidophilus KLDS 1.1003. Assessment of different polysaccharide coatings to enhance the longevity of probiotics at high temperatures of spray-drying process, storage, and targeted delivery in the gastrointestinal tract were the key objectives of the present study. The highest microencapsulation efficiencies were shown by maize (95.80%) and potato (94.30%) resistant starches. Similarly, maize resistant starch (MRS)-based composites provided the highest thermal resistance, with Tg 38.77 ± 1.10–93.13 ± 0.81 °C and showed the least 2.1 log cycles viability loss in simulated GI tract. Viability losses during storage were in the following order: control > RRS > PRS > MRS, and the inactivation rate of the microencapsulated cells followed the first-order kinetics (R2 = 0.9264–0.9918). The resistant starch-based spray-dried microcapsules possessed 27.00 ± 0.03 to 52.28 ± 1.02 µm size range and SEM micrographs showed a unified smooth surface without cracks and ruptures. These findings will expand the potential use of natural food-grade coatings in functional foods and allied industries involving spray-dried products