Automatic quantification of the microvascular density on whole slide images, applied to paediatric brain tumours

Angiogenesis is a key phenomenon for tumour progression, diagnosis and treatment in brain tumours and more generally in oncology. Presently, its precise, direct quantitative assessment can only be done on whole tissue sections immunostained to reveal vascular endothelial cells. But this is a tremendous task for the pathologist and a challenge for the computer since digitised whole tissue sections, whole slide images (WSI), contain typically around ten gigapixels. We define and implement an algorithm that determines automatically, on a WSI at objective magnification $40\times$, the regions of tissue, the regions without blur and the regions of large puddles of red blood cells, and constructs the mask of blur-free, significant tissue on the WSI. Then it calibrates automatically the optical density ratios of the immunostaining of the vessel walls and of the counterstaining, performs a colour deconvolution inside the regions of blur-free tissue, and finds the vessel walls inside these regions by selecting, on the image resulting from the colour deconvolution, zones which satisfy a double-threshold criterion. A mask of vessel wall regions on the WSI is produced. The density of microvessels is finally computed as the fraction of the area of significant tissue which is occupied by vessel walls. We apply this algorithm to a set of 186 WSI of paediatric brain tumours from World Health Organisation grades I to IV. The segmentations are of very good quality although the set of slides is very heterogeneous. The computation time is of the order of a fraction of an hour for each WSI on a modest computer. The computed microvascular density is found to be robust and strongly correlates with the tumour grade. This method requires no training and can easily be applied to other tumour types and other stainings

Reluctant Cross-Metathesis Reactions: The Highly Beneficial Effect of Microwave Irradiation

carbene complexes ; catalysis ; cross coupling ; metathesis ; olefinationInternational audienceThe beneficial effect of microwave irradiation versus classical thermal conditions is demonstrated through a series of comparative cross-metathesis reactions

Analyse prosodique de marques de l'impolitesse dans une perspective interactionnelle et didactique

Is it possible to lower communicative and intercultural misunderstanding by learning impolite intonational patterns in L2 - here French L2? The field of this essay falls within the crossing of phonetics - and within it of prosody as far as it is concerned with fondamental frequency changes - pragmatics and second languages didactics - especially politeness and impoliteness vocal expression. This research might be a first step towards the elucidation of intonational related misunderstandings between L1 and L2 speakers, and therefore comes under the field of intercultural and languages contacts. This work is based on the idea that it is possible to identify prosodic characteristics and tokens for genuine impoliteness in French, which was made from ecological conversational sets produced by French native speakers. Possible consequences in the above fields of research are considered as well as a few didactic trails in both intonational and intercultural fields.Dans quelle mesure est-il possible de réduire l'apparition de malentendus communicationnels et/ou interculturels par l'apprentissage en langue seconde, ici le français, d'intonations (im)polies ? La recherche menée dans ce mémoire s'inscrit dans un domaine au croisement de la phonétique - plus particulièrement de la prosodie en ce qu'elle s'intéresse aux variations de la fréquence fondamentale - et de la pragmatique et didactique de l'oral - plus précisément de l'expression de la politesse et de l'impolitesse. Sa visée ressortit aussi au domaine de l'interculturel et des contacts de langues, en ce qu'elle pourra constituer le point de départ de recherches portant sur l'élucidation de malentendus possiblement dus à l'intonation, malentendus communicationnels et/ou interculturels entre locuteurs de langues maternelles et locuteurs de langues allophones. Ce mémoire s'appuie sur l'hypothèse qu'il est possible de déterminer un certain nombre de traits ou marques prosodiques intrinsèquement impolis en français. Il s'agira, à partir d'énoncés produits en langue française par des locuteurs natifs du français, de tenter d'identifier et d'isoler des marqueurs acoustiques pertinents de l'impolitesse, pour envisager les retombées éventuelles dans les champs de recherche concernés et faire part de quelques pistes didactiques dans les domaines conjoints de l'intonation et de l'interculturel

RFID tags for cryogenic applications: Experimental and numerical analysis of thermo-mechanical behaviour

International audienceRFID solutions will improve the traceability of biological samples stored at low temperature (77 K) in biobanks. To achieve this goal, the reliability of RFID tags is essential. In this paper, we focus on the reliability aspect of RFID tags in harsh environment and more specifically to assembly design optimization through numerical simulations and accelerated life tests. A package-dimensioned model and a wire-interconnect centered model have been used to assess stress distribution in the package and wire bonds. We also develop a specific versatile test bench to apply thermal cycling while monitoring the functionality of the tags. We investigate three different tag configurations and demonstrate that the main failure mode is related to wire breaks. The occurrence of this failure depends mainly on the nature and thickness of the encapsulant resin which induce compressive and tensile stresses during thermal cycling. FEM results are in good agreement with observed failures

Fabrication of Capacitive Acoustic Resonators Combining 3D Printing and 2D Inkjet Printing Techniques

International audienceA capacitive acoustic resonator developed by combining three-dimensional (3D) printing and two-dimensional (2D) printed electronics technique is described. During this work, a patterned bottom structure with rigid backplate and cavity is fabricated directly by a 3D printing method, and then a direct write inkjet printing technique has been employed to print a silver conductive layer. A novel approach has been used to fabricate a diaphragm for the acoustic sensor as well, where the conductive layer is inkjet-printed on a pre-stressed thin organic film. After assembly, the resulting structure contains an electrically conductive diaphragm positioned at a distance from a fixed bottom electrode separated by a spacer. Measurements confirm that the transducer acts as capacitor. The deflection of the diaphragm in response to the incident acoustic single was observed by a laser Doppler vibrometer and the corresponding change of capacitance has been calculated, which is then compared with the numerical result. Observation confirms that the device performs as a resonator and provides adequate sensitivity and selectivity at its resonance frequency

Synthesis of functionalized tryptamines by Brønsted acid catalysed cascade reactions

An original synthetic protocol has been developed for the preparation of highly functionalized tryptamines from 2-hydroxycyclobutanone and secondary arylamines via a solvent-free Brønsted acid catalysed two-step reaction sequence

Palliative care in Dutch hospitals: A rapid increase in the number of expert teams, a limited number of referrals

Background: Palliative care expert teams in hospitals have positive effects on the quality of life and satisfaction with care of patients with advanced disease. Involvement of these teams in medical care is also associated with substantial cost savings. In the Netherlands, professional standards state that each hospital should have a palliative care team by 2017. We studied the number of hospitals that have a palliative care team and the characteristics of these teams. Methods: In April 2015, questionnaires were mailed to key palliative care professionals in all general, teaching and academic hospitals in the Netherlands. Out of 92 hospitals, 74 responded (80 %). Results: Seventy-seven percent of all participating hospitals had a palliative care team. Other services, such as outpatient clinics (22 %), palliative care inpatient units (7 %), and palliative day care facilities (4 %) were relatively scarce. The mean number of disciplines that were represented in the teams was 6,5. The most common disciplines were nurses (72 %) and nurse practitioners (54 %), physicians specialized in internal medicine (90 %) or anaesthesiology (75 %), and spiritual caregivers (65 %). In most cases, the physicians did not have labeled hours available for their work as palliative care consultant, whereas nurses and nurse practitioners did. Most teams (77 %) were only available during office hours. Twenty-six percent of the teams could not only be consulted by healthcare professionals but also by patients or relatives. The annual number of consultations for inpatients per year ranged from 2 to 680 (median: 77). On average, teams were consulted for 0.6 % of all patients admitted to the hospitals. Conclusion: The number of Dutch hospitals with a palliative care team is rapidly increasing. There are substantial differences between teams regarding the disciplines represented in the teams, the procedures and the number of consultations. The development of quality standards and adequate staffing of the teams could improve the quality and effectiveness of the teams

Organic ultrathin film adhesion on compliant substrate using scratch test technique

International audienceMany adhesion test techniques have been developed to measure the adhesion energy of thin films but they are hard to implement in the case of submicron organic thin films deposited on a flexible substrate. Recently the feasibility and repeatability of the scratch test technique as a tool for testing the adhesion and the damage behaviour of ultra-thin films on polymer substrates has been demonstrated. However, direct comparison of the critical load between samples was not straightforward since different failure mechanisms were induced. In the present work, we have performed nanoscratch experiments on submicron thin films deposited on a flexible substrate. The use of a tip radius of 5 μm enabled a unique delamination mechanism to be induced by localizing and maximizing the stress closer to the interface. We have observed an increase of the critical load on samples processed with an adhesive plasma treatment prior to thin film deposition, confirming the effectiveness of this treatment. We have also performed mechanical ageing tests on specimens and proved that the scratch test technique is sensitive enough to monitor the degradation of the interface properties. Finally, we have discussed some existing energy models. Taking into account some limitations, Laugier's model gives an upper bound for the adhesion energy