Développement et validation d’un système automatique de classification de la dégénérescence maculaire liée à l’âge

RÉSUMÉ La dégénérescence maculaire liée à l’âge (DMLA) est une des principales causes de déficience visuelle menant à une cécité irréversible chez les personnes âgées dans les pays industrialisés. Cette maladie regroupe une variété d’anomalies touchant la macula, se présentant sous diverses formes. Un des moyens les plus couramment utilisés pour rapidement examiner la rétine est la photographie de fond d’œil. À partir de ces images, il est déjà possible de détecter et de poser un diagnostic sur l’avancée de la maladie. Une classification recommandée pour évaluer la DMLA est la classification simplifiée de l’AREDS qui consiste à diviser la maladie en quatre catégories : non-DMLA, précoce, modérée, et avancée. Cette classification aide à déterminer le traitement spécifique le plus optimal. Elle se base sur des critères quantitatifs mais également qualitatifs, ce qui peut entrainer des variabilités inter- et intra-expert. Avec le vieillissement de la population et le dépistage systématique, le nombre de cas de DMLA à être examinés et le nombre d’images à être analysées est en augmentation rendant ainsi le travail long et laborieux pour les cliniciens. C’est pour cela, que des méthodes automatiques de détection et de classification de la DMLA ont été proposées, afin de rendre le processus rapide et reproductible. Cependant, il n’existe aucune méthode permettant une classification du degré de sévérité de la DMLA qui soit robuste à la qualité de l’image. Ce dernier point est important lorsqu’on travaille dans un contexte de télémédecine. Dans ce projet, nous proposons de développer et valider un système automatique de classification de la DMLA qui soit robuste à la qualité de l’image. Pour ce faire, nous avons d’abord établi une base de données constituée de 159 images, représentant les quatre catégories de l’AREDS et divers niveaux de qualité d’images. L’étiquetage de ces images a été réalisé par un expert en ophtalmologie et nous a servi de référence. Ensuite, une étude sur l’extraction de caractéristiques nous a permis de relever celles qui étaient pertinentes et de configurer les paramètres pour notre application. Nous en avons conclu que les caractéristiques de texture, de couleur et de contexte visuel semblaient les plus intéressantes. Nous avons effectué par après une étape de sélection afin de réduire la dimensionnalité de l’espace des caractéristiques. Cette étape nous a également permis d’évaluer l’importance des différentes caractéristiques lorsqu’elles étaient combinées ensemble.----------ABSTRACT Age-related macular degeneration (AMD) is the leading cause of visual deficiency and legal blindness in the elderly population in industrialized countries. This disease is a group of heterogeneous disorders affecting the macula. For eye examination, a common used modality is the fundus photography because it is fast and non-invasive procedure which may establish a diagnostic on the stage of the disease. A recommended classification for AMD is the simplified classification of AREDS which divides the disease into four categories: non-AMD, early, moderate and advanced. This classification is helpful to determine the optimal and specific treatment. It is based on quantitative criteria but also on qualitative ones, introducing inter- and intra-expert variability. Moreover, with the aging population and systematic screening, more cases of AMD must be examined and more images must be analyzed, rendering this task long and laborious for clinicians. To address this problem, automatic methods for AMD classification were then proposed for a fast and reproducible process. However, there is no method performing AMD severity classification which is robust to image quality. This last part is especially important in a context of telemedicine where the acquisition conditions are various. The aim of this project is to develop and validate an automatic system for AMD classification which is robust to image quality. To do so, we worked with a database of 159 images, representing the different categories at various levels of image quality. The labelling of these images is realized by one expert and served as a reference. A study on feature extraction is carried out to determine relevant features and to set the parameters for this application. We conclude that features based on texture, color and visual context are the most interesting. After, a selection is applied to reduce the dimensionality of features space. This step allows us to evaluate the feature relevance when all the features are combined. It is shown that the local binary patterns applied on the green channel are the most the discriminant features for AMD classification. Finally, different systems for AMD classification were modeled and tested to assess how the proposed method classifies the fundus images into the different categories. The results demonstrated robustness to image quality and also that our method outperforms the methods proposed in the literature. Errors were noted on images presenting diabetic retinopathy, visible choroidal vessels or too much degradation caused by artefacts. In this project, we propose the first AMD severities classification robust to image quality

14. Légendes des terres sereines de Pham Duy Khiêm

La France et le Vietnam ont une tradition de contes et de légendes dont l’origine se perd dans la nuit des temps, histoires effrayantes ou tristes que l’on raconte aux enfants sans savoir vraiment d’où elles viennent. Écrivain vietnamien d’expression française, Pham Duy Khiêm a recueilli ces récits et leur a donné une forme littéraire en français. Nous tenterons de mesurer dans cette expérience inédite de passage d’une langue à l’autre qui dépasse le simple exercice de traduction et d’adaptat..

SuperCDMS: Recent results on low-mass WIMPs

We present the rst search for weakly interacting massive particles (WIMPs) using the back- ground rejection capabilities of SuperCDMS 1. A blind analysis of data from an exposure of 577 kg-days leads to an upper limit on the spin-independent WIMP-nucleon cross section of 1:2 10????42 cm2 at 8 GeV. This result probes new parameter space for WIMP-nucleon scat- tering cross section for light WIMPs with masses < 6 GeV/c2 and is in tension with WIMP interpretations of recent experiments

Processing of structural neuroimaging data in young children:bridging the gap between current practice and state-of-the-art methods

The structure of the brain is subject to very rapid developmental changes during early childhood. Pediatric studies based on Magnetic Resonance Imaging (MRI) over this age range have recently become more frequent, with the advantage of providing in vivo and non-invasive high-resolution images of the developing brain, toward understanding typical and atypical trajectories. However, it has also been demonstrated that application of currently standard MRI processing methods that have been developed with datasets from adults may not be appropriate for use with pediatric datasets. In this review, we examine the approaches currently used in MRI studies involving young children, including an overview of the rationale for new MRI processing methods that have been designed specifically for pediatric investigations. These methods are mainly related to the use of age-specific or 4D brain atlases, improved methods for quantifying and optimizing image quality, and provision for registration of developmental data obtained with longitudinal designs. The overall goal is to raise awareness of the existence of these methods and the possibilities for implementing them in developmental neuroimaging studies

Excess GeV radiation and cosmic ray origin

Recent EGRET observations of the diffuse Galactic gamma-ray emission reveal a spectrum which is incompatible with the assumption that the cosmic ray spectra measured locally hold throughout the Galaxy: the spectrum above 1 GeV, where the emission is supposedly dominated by pi^0-decay, is harder than that derived from the local cosmic ray proton spectrum. We demonstrate that in case of a SNR origin of cosmic ray nucleons part of this gamma-ray excess may be attributed to the dispersion of the spectral indices in these objects. In global averages, as are gamma-ray line-of-sight integrals, this dispersion leads to a positive curvature in the composite spectrum, and hence to modified pi^0-decay gamma-ray spectra.Comment: accepted for publication in Astronomy and Astrophysic

XÁC ĐỊNH HÀM LƯỢNG NICOTIN TRONG NƯỚC TIỂU BẰNG PHƯƠNG PHÁP CHIẾT LỎNG - RẮN VÀ GC/MS

Mục đích của chúng tôi là nghiên cứu quy trình phân tích định lượng nicotin trong nước tiểu bằng phương pháp chiết lỏng rắn và phương pháp sắc kí khí khối phổ (GC-MS). Trong phần 1, chúng tôi đã báo cáo quy trình tách chiết nicotin từ nước tiểu bằng kỹ thuật chiết lỏng-rắn, pha rắn là octadecyl silica (C18) và quy trình định lượng nicotine bằng phương pháp GC-MS. Trong phần 2, chúng tôi báo cáo về kết quả phân tích định tính nicotine và các chất chuyển hóa chính của nó và áp dụng quy trình định lượng nicotine để phân tích 20 mẫu nước tiểu của những người không hút thuốc lá và 10 mẫu nước tiểu của những người hút thuốc lá ở nhà máy thuốc lá Khánh hòa. Kết quả phân tích cho thấy hàm lượng nicotine trong nước tiểu nằm trong khoảng 0,042 mg/l tới 2,074 mg/l

A longitudinal analysis of patient satisfaction with care and quality of life in ambulatory oncology based on the OUT-PATSAT35 questionnaire

BACKGROUND: In the oncology setting, there has been increasing interest in evaluating treatment outcomes in terms of quality of life and patient satisfaction. The aim of our study was to investigate the determinants of patient satisfaction, especially the relationship between quality of life and satisfaction with care and their changes over time, in curative treatment of cancer outpatients. METHODS: Patients undergoing ambulatory chemotherapy or radiotherapy in two centers in France were invited to complete the OUT-PATSAT35, at the beginning of treatment, at the end of treatment, and three months after treatment. This questionnaire evaluates patients’ perception of doctors and nurses, as well as other aspects of care organization and services. Additionally, for each patient, socio-demographic and clinical characteristics, and self-reported quality of life data (EORTC QLQ-C30) were collected. RESULTS: Of the 691 patients initially included, 561 answered the assessment at all three time points. By cross-sectional analysis, at the end of the treatment, patients who experienced a deterioration of their global health reported less satisfaction on most scales (p ≤ 0.001). Three months after treatment, the same patients had lower satisfaction scores only in the evaluation of doctors (p ≤ 0.002). Furthermore, longitudinal analysis showed a significant relationship between a deterioration in global health and a decrease in satisfaction with their doctor and, conversely, between an improvement in global health and an increase in satisfaction on the overall satisfaction scale. Global health at baseline was largely and significantly associated with all satisfaction scores measured at the following assessment time points (p < 0.0001). Younger age (<55 years), radiotherapy (versus chemotherapy) and head and neck cancer (versus other localizations) were clinical factors significantly associated with less satisfaction on most scales evaluating doctors. CONCLUSIONS: Pre-treatment self-evaluated global health was found to be the major determinant of patient satisfaction with care. The subsequent deterioration of global health, during and after treatment, emphasized the decrease in satisfaction scores, mainly in the evaluation of doctors. Early initiatives aimed at improving the delivery of care in patients with poor health status should lead to improved perception of the quality of care received

Automatic screening and grading of age-related macular degeneration from texture analysis of fundus images

Age-related macular degeneration (AMD) is a disease which causes visual deficiency and irreversible blindness to the elderly. In this paper, an automatic classification method for AMD is proposed to perform robust and reproducible assessments in a telemedicine context. First, a study was carried out to highlight the most relevant features for AMD characterization based on texture, color, and visual context in fundus images. A support vector machine and a random forest were used to classify images according to the different AMD stages following the AREDS protocol and to evaluate the features' relevance. Experiments were conducted on a database of 279 fundus images coming from a telemedicine platform. The results demonstrate that local binary patterns in multiresolution are the most relevant for AMD classification, regardless of the classifier used. Depending on the classification task, our method achieves promising performances with areas under the ROC curve between 0.739 and 0.874 for screening and between 0.469 and 0.685 for grading. Moreover, the proposed automatic AMD classification system is robust with respect to image quality

Chuyển đổi xanh cho các doanh nghiệp du lịch và khách sạn tại TP. Hồ Chí Minh thích ứng với biến đổi khí hậu

Du lịch và khách sạn là ngành mang lại hiệu quả kinh tế cao, nhưng cũng là ngành có nhiều tác động đến môi trường sinh thái. Trong bối cảnh biến đổi khí hậu (BĐKH) đang diễn ra mạnh mẽ, đồng thời với quá trình đô thị hóa tại TP. Hồ Chí Minh, hiện chuyển đổi xanh trong ngành khách sạn và du lịch sẽ góp phần giảm tiêu thụ tài nguyên, ô nhiễm môi trường và thúc đẩy phát triển kinh tế bền vững. Bài viết phân tích thực trạng chuyển đổi xanh ở các doanh nghiệp du lịch và khách sạn trên địa bàn TP. Hồ Chí Minh. Trên cơ sở đó, đề xuất một số giải pháp để giúp các doanh nghiệp này tham gia vào cuộc cách mạng xanh, góp phần vào sự phát triển bền vững của đất nước trong giai đoạn hiện nay. [Tourism and hotels are high economic efficiency industries but at the same time also have various impacts on the ecological environment. In the context that climate change has taken place strongly, with the urbanization process in Ho Chi Minh City, green transition in the hotel and tourism industries will contribute to reducing resource consumption, reducing environmental pollution, and promoting sustainable economic development. This article analyzes the status of green transition in tourism and hotel businesses in Ho Chi Minh City. On that basis, proposes some solutions to help these businesses participate in the green revolution, contributing to the sustainable development of the country in the current period.

THÀNH PHẦN, MẬT ĐỘ VÀ SỰ PHÂN BỐ TRỨNG CÁ VÀ CÁ BỘT VÙNG ĐẦM THỊ NẠI, TỈNH BÌNH ĐỊNH

Kết quả của bài báo là một phần nội dung của nhiệm vụ độc lập cấp nhà nước “Nghiên cứu cơ sở khoa học nhằm xây dựng các giải pháp phát triển nuôi trồng thủy sản bền vững tại đầm Thị Nại, tỉnh Bình Định” do Viện Hải dương học chủ trì giai đoạn 2008-2010. Kết quả hai chuyến khảo sát vào mùa mưa (11/2008) và mùa khô (4/2009) với 18 trạm thu mẫu ở đầm Thị Nại đã thu được 20.588 trứng và 4.458 cá bột. Mật độ trung bình vào mùa mưa (11/2008) là 3,58 trứng và 49,34 cá bột/100m3; vào mùa khô (4/2009) là 951,38 trứng và 75,54 cá bột/100m3, cao hơn nhiều so với mùa mưa. Có sự khác biệt rõ nét về mật độ trứng cá và cá bột giữa các khu vực nghiên cứu và thời gian khảo sát. Vùng tập trung của trứng cá và cá bột là xung quanh cồn Chim ở giữa đầm và khu vực gần cửa đầm; mùa khô (4/2009) có nhiều loài cá đẻ hơn so với mùa mưa (11/2008). Thành phần trứng cá và cá bột gồm 30 họ thuộc 10 bộ, trong đó trứng cá thuộc họ cá mối (Synodontidae), giống cá cơm trổng (Stolephorus), cá cơm (Encrasicholina) và họ cá trích (Clupeidae) là xác định được, chiếm 13%, riêng họ cá mối chiếm 12,5%. Cá bột có 29 họ, họ cá bống (Gobiidae) chiếm ưu thế 81,58%, tiếp theo là họ cá trích (Clupeidae) chiếm 4,08%, họ cá lon (Blennidae) chiếm 3,68%, giống cá sơn biển (Ambasis sp) chiếm 1,35%. Các họ cá khác mỗi loại chiếm tỉ lệ dưới 1%.  Summary: The paper presented as a part of the results belonging to the national independent project “Studying on scientific fundamentals for formulating solutions on sustainable aquaculture development at Thi Nai lagoon, Binh Dinh province” carried out by Institute of Oceanography during 2008-2010. The results of two surveys during the rainy season (11/2008) and dry season (4/2009) with 18 stations within Thi Nai lagoon collected 20588 fish eggs and 4458 fish larvae. The average densities on the rainy season (11/2008) were 3.58 fish eggs and 49.34 fish larvae/100m3; the average densities on the dry season (4/2009) were 951.38 fish eggs and 75.54 fish larvae/100m3, which were much higher than those on the rainy season. There was distinct difference in densities of the fish eggs and larvae according to the surveyed areas and seasons. The high densities of fish eggs and fish larvae were observed at Chim hillock surrounding the center and nearby the mouth of the lagoon; more fish species bred during dry season (4/2009) compared to that during rainy season (11/2008). The composition of fish eggs and larvae included 30 families belonging to 10 orders, in which the fish eggs belonging to Synodontidae, Stolephorus, Encrasicholina and Clupeidae were identified, corresponding to 13%, in which Synodontidae 12.5%. Fish larvae included 29 families, in which Gobiidae 81.58%, followed by Clupeidae 4.08%, Blennidae 3.68%, Ambasis sp 1.35%. Other families, each of them below 1%