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Over the last decades, the use of artificial intelligence, machine learning and deep learning in medical fields has skyrocketed. Well known for their results in segmentation, motion management and posttreatment outcome tasks, investigations of machine learning and deep learning models as fast dose calculation or quality assurance tools have been present since 2000. The main motivation for this increasing research and interest in artificial intelligence, machine learning and deep learning is the enhancement of treatment workflows, specifically dosimetry and quality assurance accuracy and time points, which remain important time-consuming aspects of clinical patient management. Since 2014, the evolution of models and architectures for dose calculation has been related to innovations and interest in the theory of information research with pronounced improvements in architecture design. The use of knowledge-based approaches to patient-specific methods has also considerably improved the accuracy of dose predictions. This paper covers the state of all known deep learning architectures and models applied to external radiotherapy with a description of each architecture, followed by a discussion on the performance and future of deep learning predictive models in external radiotherapy. [ABSTRACT FROM AUTHOR]

In the marine sector, hydraulic machinery suffers severe damage from cavitation erosion. Although amorphous carbon (a-C) coatings are an effective measure to enhance the cavitation erosion resistance (CER), their widespread application is hindered by their metastable nature characterized by internal stress. In this study, a planification strategy was employed via different sp 2 /sp 3 distributions (including uniform ones with different sp 2 /sp 3 levels and periodically transitional ones with different periods), aiming to construct a pure a-C coating that enhances CER on 316L stainless steel by modulating the bias during magnetron sputtering. The effects of the sp 2 /sp 3 distributions on the microstructure, chemical bonding, adhesion strength, fracture toughness, corrosion resistance and CER was investigated and compared with the coatings featuring uniform sp 2 /sp 3 distributions. The results show that the periodic-mode coatings exhibit much higher CER due to their lower internal stress, excellent adhesion strength, enhanced fracture toughness and high corrosion resistance. After the cavitation erosion test for 4 h, the periodic-mode coatings only show striped structures without any coating delamination, along with less graphitization tendency during cavitation erosion. Hence, the design approach of periodic sp 2 /sp 3 carbon bonds provides a promising new direction for marine equipment with improved CER and potential applications in various other environments. [Display omitted] • A planification strategy is successfully employed to optimize a-C coatings by modulating the distribution of carbon bonds. • The periodic transition of sp 2 and sp 3 bonds in a-C coatings effectively mitigates the internal stress. • The periodic-mode a-C coatings exhibit superior adhesion strength and fracture toughness compared to the constant-mode coatings. • The periodic-mode coatings show improved cavitation erosion resistance with the striped morphology appearing four times later than the constant-mode coatings. • The enhanced cavitation resistance of periodic-mode coatings is due to low internal stress, high toughness, and reduced graphitization. [ABSTRACT FROM AUTHOR]

The formal Event-B method makes it possible to obtain systems or software correct by construction. The modeling activity aims to establish formal models in Event-B. As for the proof activity, it aims at correcting these models. A proven Event-B model is not necessarily valid. We propose to open the Event-B formal method on PDDL in order to further validate Event-B models. We aim to validate the dynamic properties related to the sequence of events authorized on Event-B models. PDDL is a de facto standard language for planning problems. It is equipped with planners to automatically generate solution-plans. To achieve this, we successfully used the MDE approach, Xtext to create an integrated development environment specific to the Event-B language and the Xtend tool to implement our transformation EventB2PDDL and produce PDDL descriptions using a top-down approach. [ABSTRACT FROM AUTHOR]

The 2020 recommendations for good brachytherapy procedures ("Recorad") are updated based on the 2016 article. This new brachytherapy article took into account recent data published in the literature as well as international recommendations. The different brachytherapy steps are successively described from the treatment preparation (brachytherapy technique prescription; procedure and material, dedicated images for planification, dose distribution analysis and validation) to the end of the procedure as well as post-treatment surveillance. [ABSTRACT FROM AUTHOR]

Imaging is involved in the management of uterine cervical cancer with several objectives: 1/to assess local and lymph node extension of the initial disease; 2/evaluate treatment response to conservative therapy; 3/detect recurrences. Pelvic MRI is the first-line examination in all these indications. It is the key element for delineation after image fusion when the indication of chemoradiation therapy is made. It is also essential for guiding the placement of applicators and optimising the dosimetry of brachytherapy. The diffusion-weighted acquisition is a sequence sensitive to the motion of water molecules. It allows distinguishing water molecules with free diffusion from water molecules with diffusion restricted by obstacles such as cell membranes or the cytoskeleton. The diffusion is thus connected to the cellularity of the explored tissue, and the cancers, being hypercellular, will present a high signal. It thus provides additional information thanks to a high contrast between the tumour and the surrounding tissues, facilitating detection, evaluation of the volume and extent of the disease. [ABSTRACT FROM AUTHOR]

Imaging is critical to each step of precision radiation therapy, i.e. planning, setup, delivery and assessment of response. Hadrontherapy can be considered to deliver more precise dose distribution that may better spare normal tissues from intermediate low doses of radiation. In addition, hadrontherapy using high linear energy transfer ions may also be used for dose escalation on biological target volumes defined by functional imaging. However, the physical characteristics of hadrontherapy also make it more demanding in terms of imaging accuracy and image-based dose calculation. Some of the developments needed in imaging are specific to hadrontherapy. The current review addresses current status of imaging in proton therapy and the drawbacks of photon-based imaging for hadrons. It also addresses requirements in hadrontherapy planning with respect to multimodal imaging for proper target and organ at risk definition as well as to target putative radioresistant areas such as hypoxic ones, and with respect to dose calculation using dual energy CT, MR-proton therapy, proton radiography. Imaging modalities, such as those used in photon-based radiotherapy (intensity modulated and stereotactic radiotherapy), are somewhat already implemented or should be reaching "routine" hadrontherapy (at least proton therapy) practice in planning, repositioning and response evaluation optimizable within the next five years. Online monitoring imaging by PET, as currently developed for hadrontherapy, is already available. Its spatiotemporal limits restrict its use but similar to prompt gamma detection, represents an area of active research for the next 5 to 10 years. Because of the more demanding and specific dose deposit characteristics, developments image-guided hadrontherapy, such as specific proton imaging using tomography or ionoacoustics, as well as delivery with MR-proton therapy, may take another 10 years to reach the clinics in specific applications. Other aspects are briefly described such as range monitoring. Finally, the potential of imaging normal tissue changes and challenges to assess tumour response are discussed. [ABSTRACT FROM AUTHOR]

Gantry collision is a concern in linac-based stereotactic radiosurgery (SRS). Without collision screening, the planner may compromise optimal planning, unnecessary re-planning delays can occur, and incomplete treatments may be delivered. To address these concerns, we developed a software for collision prediction based on simple machine measurements. Three types of collision were identified; gantry-couch mount, gantry-couch and gantry-patient. Trigonometric formulas to calculate the distance from each potential point of collision to the gantry rotation axis were generated. For each point, collision occurs when that distance is greater than the gantry head to gantry rotational axis distance. The colliding arc for each point is calculated. A computer code incorporating these formulas was generated. The inputs required are the couch coordinates relative to the isocenter, the patient dimensions, and the presence or absence of a circular SRS collimator. The software outputs the collision-free gantry angles, and for each point, the shortest distance to the gantry or the colliding sector when collision is identified. The software was tested for accuracy on a TrueBEAM® machine equipped with BrainLab® accessories for 80 virtual isocenter-couch angle configurations with and without a circular collimator and a parallelepiped phantom. The software predicted the absence of collision for 19 configurations. The mean absolute error between the measured and predicted gantry angle of collision for the remaining 61 cases was 0.86 (0.01–2.49). This tool accurately predicted collisions for linac-based intracranial SRS and is easy to implement in any radiotherapy facility. [ABSTRACT FROM AUTHOR]

La scanographie quadridimensionnelle, également appelée 4D-CT, a vu le jour au début des années 2000. C'est une méthode d'acquisition dynamique des données tomodensitométriques synchronisée avec la respiration du patient. Elle permet une observation anatomique en fonction du temps. Différents systèmes ont été commercialisés et utilisés en clinique, notamment pour la planification des radiothérapies. Cet outil permet une meilleure estimation des changements de forme et de position de la tumeur et des organes à risque. Avec le développement des techniques innovantes et l'essor des irradiations stéréotaxiques, la scanographie quadridimensionnelle constitue un outil précieux pour estimer les incertitudes liées aux mouvements respiratoires. Cette technique présente également certaines limites, avec notamment le risque d'artéfacts. La qualité de l'examen peut ainsi être dégradée chez certains patients avec une respiration irrégulière. Nous vous proposons ici une synthèse sur cette technique détaillant son principe de fonctionnement, ses avantages et ses principales limites. The four-dimensional scannography, also called 4D-CT, was created in the early 2000s. This method enables the aquistion of CT-scans synchronised with the patient's breathing. It allows an anatomical observation depending on the time. Different systems have been marketed. They are commonly used in treatment planning. It allows to take into account respiratory motion, considering the changes of shape and position of the tumor and organs. In the age of new techniques and stereotactic irradiations, 4D-CT is a valuable tool for estimating the uncertainties associated with respiratory movements, This technique also presents some limitations, including artifacts. The quality of the examination can be degraded in some patients with irregular respiration. Here we propose a summary of this technique detailing its principle of operation, its advantages and its main limits. [ABSTRACT FROM AUTHOR]

Résumé Objectifs Dans cet article est décrite l’évolution des soins psychiatriques sur l’actuel territoire de la République de Moldavie, faisant autre fois partie de l’État Moldave, puis province russe de 1812 à 1918, qui appartiendra ensuite à la Roumanie pour devenir soviétique de 1940 à 1991 et qui depuis est devenue République indépendante. Méthodes L’analyse longitudinale et rétrospective, en utilisant les méthodes empiriques et de comparaison des données bibliographiques, statistiques, des documents, des rapports de fonctionnement, de témoignages, a permis une synthèse et une description évolutive des soins psychiatriques en Moldavie. Résultats Suite à l’analyse effectuée, nous avons tracé les étapes du développement de la psychiatrie en Moldavie. Au Moyen Âge, depuis la constitution de l’État Moldave, il y avait une attitude humaniste envers les malades mentaux, l’église chrétienne, qui s’occupait de ces malades, était très tolérante et protectrice envers eux. La deuxième étape commence après l’annexion de la Moldavie à l’Empire Russe en 1812, avec l’ouverture des premiers lits dans des Hôpitaux généraux et l’ouverture en 1895 du premier hôpital psychiatrique, qui est devenu à l’époque, un des plus progressif et moderne parmi les Hôpitaux Psychiatriques de Russie, avec la plus courte durée de séjour, un nombre important des mesures de réhabilitation par le travail, par l’organisation des colonies de malades, par la vie dans la communauté. La même tendance s’est poursuivie pendant la période roumaine, quand ce territoire a retrouvé ses liens culturels et linguistiques, avec un progrès évident dans le traitement des maladies liées à la malnutrition (la pellagre) et une diminution importante du nombre de ces malades. La période soviétique a été marquée par des mouvements contradictoires. D’un côté, un développement important des soins hospitaliers, avec l’ouverture des nouveaux centres hospitaliers, une assurance suffisante de médicaments et des soins de réhabilitation. En même temps, un élargissement important des critères de diagnostic de la schizophrénie qui pouvaient servir de motif d’hospitalisation sous contrainte. Les personnes qui manifestaient des traits paranoïdes, borderline , schizoïdes, étaient hospitalisées avec le diagnostic de schizophrénie légère (lente), ce que sous-entendait un traitement obligatoire. En dehors de cela, un dispositif important de réhabilitation a été mis au service des patients. La période actuelle se caractérise par une ouverture importante de la société concernant les malades psychiques avec la diminution de nombre de lits intra-hospitaliers, l’ouverture des centres communautaires. En même temps, il y a un déficit important de médicaments de dernière génération qui ne sont pas accessibles à la majorité de la population. L’assurance maladie est mise en place depuis quelques années et les patients ont la possibilité de recevoir un minimum de soins. Discussion L’évolution des soins psychiatriques sur l’actuel territoire de la République Moldave, qui est passée en un siècle de temps du régime tsariste au capitalisme roumain, puis au système soviétique pour devenir un pays indépendant avec une aspiration européenne, a connu des changements importants avec un enrichissement des expériences à travers les époques et les régimes. Les bases de la psychiatrie moldave moderne ont été posées par la psychiatrie russe, qui était une continuité de l’école allemande de psychiatrie. Les questions les plus importantes, aujourd’hui, sont liées au futur développement et à la réorganisation de la santé mentale avec l’accent sur les soins ambulatoires et la réhabilitation. Les problèmes majeurs à dépasser sont la stigmatisation et la discrimination du malade mental, le développement des structures sociales, dans un contexte économique et démographique très difficile. Malgré cette situation, le projet de réforme de la santé mentale se développe dans le pays, implémenté par l’Institut Trimbus (Pays Bas), institut de Santé Mentale et des addictions et financé par le Gouvernement Suisse pour la période 2015-2018. Le but du projet est la mise en place du modèle communautaire de santé mentale avec comme objectif une diminution importante de nombre de lits dans les hôpitaux psychiatriques. Conclusion Ce travail nous permet de faire une rétrospective historique de la prise en charge des patients psychiatriques sur l’actuel territoire de la Moldavie, ainsi qu’une présentation de la situation actuelle d’un système de santé mentale en pleine mutation et l’alignement au modèle de psychiatrie communautaire, malgré une situation financière très difficile. Objectives This article describes the development of psychiatric care in the present territory of the Republic of Moldova, which was formerly a part of the Moldavian Principality, and then a Russian province from 1812 to 1918. Afterwards, it belonged to Romania, before becoming a Soviet republic from 1940 to 1991 when it became an independent country. Methods A longitudinal, retrospective analysis, using empirical methods and comparisons of bibliographic and statistical data, documents, activity reports, and evidence, enabled a synthesis and the description of the evolution of psychiatric care in Moldova. Results By way of this analysis, we have delineated the different stages in the development of psychiatry in Moldova. In the Middle Ages, after the establishment of the Moldavian Principality, there was a humanist attitude towards mental patients. The Christian church, which often had the charge of these patients, was tolerant and protective towards them. The second stage started after the annexation of Moldova to the Russian Empire in 1812, the establishment of the first beds in general hospitals, and the opening of the first psychiatric hospital in 1895, which became at the time one of the most progressive and modern among the psychiatric hospitals of Russia, with the shortest duration of hospitalisation, and a large number of rehabilitation measures entailing work projects, patient colonies, and life in the community. This tendency persisted during the Romanian period, when the territory retrieved its cultural and linguistic links, making visible progress in the treatment of patients in the area of malnutrition (pellagra), and achieving a considerable reduction in the number of patients with pellagra. The Soviet period saw contradictory trends. On the one hand, the considerable development of hospital care, as a result of the establishment of new hospital centres, adequate drug supplies and the availability of rehabilitation care. At the same time, there was a considerable broadening of the criteria for schizophrenia diagnosis, which could serve as grounds for coercive hospitalisation. Individuals who displayed paranoid, borderline, schizoid manifestations were hospitalised with a diagnosis of mild schizophrenia, which meant compulsory treatment. In addition to this, far-reaching rehabilitation provisions were developed for the patients. The current period is characterised by a wide receptiveness in society towards psychiatric patients, a significant reduction in inpatients beds and the opening of centres in the community. At the same time, there is a considerable shortage of last-generation drugs which are not available for the majority of the population. A medical insurance system has been in place for several years and patients can receive basic care. Discussion The development of psychiatric care in the present territory of the Republic of Moldova over one century, from the tsarist regime to Romanian capitalism, then to the Soviet system and finally the independent State with European aspirations, has seen significant changes and enriching experiences at all stages and under all regimes. The foundations of the modern Moldavian psychiatry were laid by Russian psychiatry which followed on from the German psychiatric school. At present, the main concerns are related to future development and to the reorganisation of mental health, with particular emphasis on outpatient care and rehabilitation. The main problems to be overcome are the stigmatisation and discrimination of psychic patients, and the need for social structures in a very difficult economic and demographic context. Despite this situation, a mental health reform project is being implemented in the country over the period 2015-2018 by Trimbos Institute (the Netherlands Institute of Mental Health and Addiction), financed by the Swiss Government. The aim of the project is to develop a community mental health model so as to considerably reduce the number of beds in psychiatric hospitals. Conclusion This work provides a retrospective account of psychiatric care in the present territory of the Republic of Moldova, and describes the current situation of the mental health system which is undergoing a process of fundamental change modelled on community psychiatry, despite the very difficult financial situation. [ABSTRACT FROM AUTHOR]

Résumé: La planification de la radiothérapie a connu récemment des développements considérables, avec l’émergence de techniques telles que la radiothérapie conformationnelle, la radiothérapie conformationnelle avec modulation d’intensité (RCMI) ou encore la radiothérapie en conditions stéréotaxiques. La délimitation de volumes cibles précis a ainsi pris toute son importance. Le recours à l’imagerie hybride par tomographie par émission de positions (TEP) couplée à la tomodensitométrie (TDM) permet l’accès à une information fonctionnelle associée à une information morphologique. La collaboration étroite entre oncologues radiothérapeutes et médecins nucléaires offre la promesse d’assurer une délinéation plus optimale des volumes tumoraux tout en préservant les organes à risques. Depuis quelques années, de plus en plus de travaux explorent ce domaine, et nous proposons ici une revue de la littérature, classée par localisation : digestive, gynécologique et prostatique, quant à l’utilisation de la TEP dans la délinéation des aires ganglionnaires pelviennes. [ABSTRACT FROM AUTHOR]

Abstract: The implementation of new techniques of imaging in the daily practice of the radiation oncologist is a major advance in these last 10 years. This allows optimizing the therapeutic intervals and locoregional control of the disease while limiting side effects. Among them, positron emission tomography (PET) offers an opportunity to the clinician to obtain data relative to the tumoral biological mechanisms, while benefiting from the morphological images of the computed tomography (CT) scan. Recently hybrid PET/CT has been developed and numerous studies aimed at optimizing its use in the planning, the evaluation of the treatment response and the prognostic value. The choice of the radiotracer (according to the type of cancer and to the studied biological mechanism) and the various methods of tumoral delineation, require a regular update to optimize the practices. We propose throughout this article, an exhaustive review of the published researches (and in process of publication) until December 2011, as user guide of PET/CT in all the aspects of the modern radiotherapy (from the diagnosis to the follow-up): biopsy guiding, optimization of treatment planning and dosimetry, evaluation of tumor response and prognostic value, follow-up and early detection of recurrence versus tumoral necrosis. In a didactic purpose, each of these aspects is approached by primary tumoral location, and illustrated with representative iconographic examples. The current contribution of PET/CT and its perspectives of development are described to offer to the radiation oncologist a clear and up to date reading in this expanding domain. [Copyright &y& Elsevier]

Abstract: Positron emission tomography is a functional imaging technique that allows the detection of the regional metabolic rate, and is often coupled with other morphological imaging technique such as computed tomography. The rationale for its use is based on the clearly demonstrated fact that functional changes in tumor processes happen before morphological changes. Its introduction to the clinical practice added a new dimension in conventional imaging techniques. This review presents the current and proposed indications of the use of positron emission/computed tomography for prostate, bladder and testes, and the potential role of this exam in radiotherapy planning. [Copyright &y& Elsevier]

Abstract: This article looks at the development of algorithm-based tools with a view to meeting future operational needs for intelligence. More precisely, it concerns the management of sensors and proposes a new heuristic capable of optimizing (globally speaking and subject to constraints) the planning of sensors to meet the intelligence needs expressed by the High Command. [Copyright &y& Elsevier]

Copyright of Psychologie Française is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Tourism Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Tourism Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Tourism Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Tourism Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Tourism Research is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Purpose of radiation treatment after conservative surgery for breast cancer is improvement of long-term local control rate and reduction of heart and pulmonary toxic events for women with long life expectancy. Breast irradiation with intensity modulation might be promising, as results of treatment planning (dose–volume histogram and normal tissue complication probability) showed. Project of our study is to evaluate the advantage of each following techniques: wedged plans, electronic compensation and intensity modulation. [Copyright &y& Elsevier]