CompNet: Complementary Segmentation Network for Brain MRI Extraction

Brain extraction is a fundamental step for most brain imaging studies. In this paper, we investigate the problem of skull stripping and propose complementary segmentation networks (CompNets) to accurately extract the brain from T1-weighted MRI scans, for both normal and pathological brain images. The proposed networks are designed in the framework of encoder-decoder networks and have two pathways to learn features from both the brain tissue and its complementary part located outside of the brain. The complementary pathway extracts the features in the non-brain region and leads to a robust solution to brain extraction from MRIs with pathologies, which do not exist in our training dataset. We demonstrate the effectiveness of our networks by evaluating them on the OASIS dataset, resulting in the state of the art performance under the two-fold cross-validation setting. Moreover, the robustness of our networks is verified by testing on images with introduced pathologies and by showing its invariance to unseen brain pathologies. In addition, our complementary network design is general and can be extended to address other image segmentation problems with better generalization.Comment: 8 pages, Accepted to MICCAI 201

Evaluation des propriétés antimicrobiennes de quatre plantes de la flore togolaise utilisées en médecine traditionnelle dans le traitement des diarrhées infantiles

Ce travail a été entrepris afin de justifier l'utilisation traditionnelle de quatre plantes de la flore togolaise dans le traitement des diarrhées infantiles. Les potentiels antibactériens et antifongiques des extraitshydroéthanoliques des feuilles de Byrsocarpus coccineus, Leptadenia hastata, Phyllanthus muellerianus, Pupalia lappacea, et d'écorces de racine de Phyllanthus muellerianus, ont été évalués in vitro par la méthode de dilution en milieu liquide associée à l'étalement sur milieux gélosés. Les germes : Escherichia coli, Shigella flexneri, Salmonella typhi, Salmonella enteritidis et Candida albicans, souvent incriminés dans les maladies diarrhéiques infantiles ont été testés. Les extraits hydroéthanoliques de ces plantes ont inhibé à divers degrés lacroissance in vitro des germes testés, à l'exception de ceux des feuilles de P. lappacea et de B. coccineus qui ont été inactifs respectivement sur C. albicans et S. flexneri. Les concentrations minimales inhibitrices desextraits ont varié de 0,5 à 4 mg/ml. Le test phytochimique a montré que tous ces extraits contiennent des alcaloïdes, des flavonoïdes, des tanins et des saponosides, sauf les extraits des feuilles de P. lappacea et de L.hastata qui ne possèdent respectivement pas d'alcaloïdes et de tanins.Mots clés: Infections diarrhéiques, extraits végétaux, antimicrobiens, phytochimie

Experimental investigation on the effects of the geometry of microchannels based heat sinks on the flow boiling of HFE-7100

In this paper, nine Microchannel Heat sinks (MCHs) all with channel lengths of 20 mm and heights of 1 mm but with different aspect ratios 1.33; 2 and 4, wall thicknesses 0.25-0.75 were tested in single and two-phase flows using the HFE-7100 as the working fluid. Three different scenarios were established, changing only the inlet temperature of the fluid: ambient (18-25 degrees C), intermediate (38-42 degrees C) and near saturation (55-58 degrees C). In all experiments the flow at the inlet was in the laminar region with Reynolds (Re) number values ranging from 50 to 130. A thermographic camera was placed below the microchannel heat sink, to observe the cooling process during the flows. Thus, the main objective of this study is to evaluate the effects of channel geometry on both the overall heat transfer coefficient and the pressure losses. The results demonstrate that, for both single and two phase flow, narrower channels exhibit better thermal performance but higher-pressure losses than wider channels. When maintaining channel width constant and varying thicknesses, channels with wider walls presented higher overall heat transfer coefficients and lower pressure losses

Hygienic quality of ready-to-eat salads sold in the street and a modern restaurant in Lomé, TOGO

Poisoning following salads consumption was often reported in Lomé. This study was carried out to evaluate contamination of salads sold in Lomé. Sixty salad samples from modern restaurant (Domino), seventy from street sellers and forty of fresh vegetables from two markets were randomly collected. Microbiological quality of samples was examined on the basis of AFNOR methods and criteria. Salad selling occurs in room temperature. That modern restaurant uses cold to preserve foods. Microbial analyzes revealed that, Total viable count (TVC) load ranged from 2.15x104 – 9.2x1010 and 1.8x103 – 2.7x107 with 10% and 86.66% of satisfactory quality samples respectively for Domino and Street salads. Total and thermo-tolerant coliforms load ranged from 60-3.4x106 and 0-6.2x103 respectively for street salads with 14.28% and 57.15% of satisfactory samples. Domino samples located between 0-7x103 and 0-2.5x103 with 96.66% and 81.33% of conformity respectively. E. coli and S. aureus were isolated (0-2.5x103 and 0-103) respectively with 77.14% and 84.28% of satisfactory samples for street salads. These bacteria did not induce any conform samples. Salmonella spp were not found in salads and raw vegetable. Application of good hygiene practices rules would help to reduce disease risk related to the presence of pathogenic germs like E. coli and S. aureus.© 2015 International Formulae Group. All rights reserved.Keywords: Food poisoning, Vegetable food, microbiological safet

Impact of Covid-19 on Mental Health among Healthcare Workers in India: A Mixed-Methods Systematic Review

Healthcare workers (HCWs) experienced significant mental health challenges during the COVID-19 pandemic. This review aimed comprehensively assess the impact of the COVID-19 pandemic on the mental health of HCWs in India. A mixed-methods review adopted a results-based convergent approach incorporating quantitative and qualitative data. A comprehensive literature search was conducted in relevant databases: PubMed-MEDLINE, CINAHL, Web of Science, and ProQuest. All available full-text studies in the English language that assessed the mental health outcomes (anxiety, stress, depression) of HCWs during the pandemic and published till February 28, 2022, were included. A total of 31 studies were included in this review (27 quantitative studies, three qualitative studies, and one mixed-method study). The pooled prevalence of depression, anxiety, and stress was 32.96%, 29.49%, and 33.47 %, respectively among the HCWs in India. The qualitative analysis resulted in the themes: challenges faced, and coping strategies used during the COVID-19 pandemic. Integration of quantitative and qualitative findings using social determinants of health framework resulted in various contributing factors and coping strategies. There is a need for a supportive work environment, mental health support, and mental health policies for HCWs in India

The effectiveness of integrating educational robotic activities into higher education Computer Science curricula: a case study in a developing country

In this paper, we present a case study to investigate the effects of educational robotics on a formal undergraduate Computer Science education in a developing country. The key contributions of this paper include a longitudinal study design, spanning the whole duration of one taught course, and its focus on continually assessing the effectiveness and the impact of robotic-based exercises. The study assessed the students' motivation, engagement and level of understanding in learning general computer programming. The survey results indicate that there are benefits which can be gained from such activities and educational robotics is a promising tool in developing engaging study curricula. We hope that our experience from this study together with the free materials and data available for download will be beneficial to other practitioners working with educational robotics in different parts of the world

Elastic properties of graphyne-based nanotubes

Graphyne nanotubes (GNTs) are nanostructures obtained from rolled up graphyne sheets, in the same way carbon nanotubes (CNTs) are obtained from graphene ones. Graphynes are 2D carbon-allotropes composed of atoms in sp and sp2 hybridized states. Similarly to conventional CNTs, GNTs can present different chiralities and electronic properties. Because of the acetylenic groups (triple bonds), GNTs exhibit large sidewall pores that influence their mechanical properties. In this work, we studied the mechanical response of GNTs under tensile stress using fully atomistic molecular dynamics simulations and density functional theory (DFT) calculations. Our results show that GNTs mechanical failure (fracture) occurs at larger strain values in comparison to corresponding CNTs, but paradoxically with smaller ultimate strength and Young's modulus values. This is a consequence of the combined effects of the existence of triple bonds and increased porosity/flexibility due to the presence of acetylenic groups

Phosphate/Silicate Ratio Allows for Fine-Tuning of Bioactive Glass Crystallisation and Glass-Ceramic Microstructure

A combination of XRD, solid-state NMR and state-of-the-art imaging techniques were used to investigate how the calcium orthophosphate/calcium silicate ratio affects the crystallisation of bioactive glasses in the system SiO2-P2O5-CaO-CaF2. In the phosphate-free glass, xonotlite, wollastonite and cuspidine crystallised. From 2.4 mol% P2O5, fluorapatite also formed, while the amount of wollastonite decreased. Crystallisation tendency was low for low phosphate contents, while above 3 mol% P2O5 it increased. The phosphate-free glass showed a volume crystallisation mechanism with constant activation energy. By contrast, the glass with the largest phosphate to silicate ratio showed both volume and surface crystallisation, causing a pronounced decrease in activation energy with crystallisation degree. This work shows that by changing the phosphate/silicate ratio we can determine which crystal phases form, obtaining for example fluorapatite-free or wollastonite-free glass-ceramics, depending on the desired application and properties such as mechanical strength or activity in contact with physiological solutions