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International audience; Purpose. Motion-mask segmentation from thoracic computed tomography (CT) images is the process of extracting the region that encompasses lungs and viscera, where large displacements occur during breathing. It has been shown to help image registration between different respiratory phases. This registration step is, for example, useful for radiotherapy planning or calculating local lung ventilation. Knowing the location of motion discontinuity, that is, sliding motion near the pleura, allows a better control of the registration preventing unrealistic estimates. Nevertheless, existing methods for motion-mask segmentation are not robust enough to be used in clinical routine. This article shows that it is feasible to overcome this lack of robustness by using a lightweight deep-learning approach usable on a standard computer, and this even without data augmentation or advanced model design.Methods. A convolutional neural-network architecture with three 2D U-nets for the three main orientations (sagittal, coronal, axial) was proposed. Predictions generated by the three U-nets were combined by majority voting to provide a single 3D segmentation of the motion mask. The networks were trained on a database of nonsmall cell lung cancer 4D CT images of 43 patients. Training and evaluation were done with a K-fold cross-validation strategy. Evaluation was based on a visual grading by two experts according to the appropriateness of the segmented motion mask for the registration task, and on a comparison with motion masks obtained by a baseline method using level sets. A second database (76 CT images of patients with early-stage COVID-19), unseen during training, was used to assess the generalizability of the trained neural network.Results. The proposed approach outperformed the baseline method in terms of quality and robustness: the success rate increased from urn:x-wiley:00942405:media:mp15347:mp15347-math-0001 to urn:x-wiley:00942405:media:mp15347:mp15347-math-0002 without producing any failure. It also achieved a speed-up factor of 60 with GPU, or 17 with CPU. The memory footprint was low: less than 5 GB GPU RAM for training and less than 1 GB GPU RAM for inference. When evaluated on a dataset with images differing by several characteristics (CT device, pathology, and field of view), the proposed method improved the success rate from urn:x-wiley:00942405:media:mp15347:mp15347-math-0003 to urn:x-wiley:00942405:media:mp15347:mp15347-math-0004.Conclusion. With 5-s processing time on a mid-range GPU and success rates around urn:x-wiley:00942405:media:mp15347:mp15347-math-0005, the proposed approach seems fast and robust enough to be routinely used in clinical practice. The success rate can be further improved by incorporating more diversity in training data via data augmentation and additional annotated images from different scanners and diseases. The code and trained model are publicly available.

International audience; Although neural networks have proven very successful in a number of medical image analysis applications, their use remains difficult when targeting subtle tasks such as the identification of barely visible brain lesions, especially given the lack of annotated datasets. Good candidate approaches are patch-based unsupervised pipelines which have both the advantage to increase the number of input data and to capture local and fine anomaly patterns distributed in the image, while potential inconveniences are the loss of global structural information. We illustrate this trade-off on Parkinson's disease (PD) anomaly detection comparing the performance of two anomaly detection models based on a spatial auto-encoder (AE) and an adaptation of a patch-fed siamese auto-encoder (SAE). On average, the SAE model performs better, showing that patches may indeed be advantageous.

An online survey among French-speaking Belgians (N=7711) investigated self-reported changes in alcohol consumption during the first COVID-19-related lockdown (March 17th - May 4th 2020). Population-weighted estimates indicated that 31.37% of the population increased consumption during lockdown, 30.32% decreased consumption and 38.31% reported unchanged consumption. The magnitude of change was higher for "decreasers" than "increasers", resulting in a slight reduction in overall consumption. A multiple regression analysis revealed that age, occupational status, number of cohabitants, perceived alcohol accessibility, drinking motivations and previous consumption predicted consumption changes. The lockdown was thus associated with consumption modifications among French-speaking Belgians, without a prevailing direction of change.

The global outbreak of coronavirus disease 2019 (COVID-19) and the resulting lockdown measures have raised concerns regarding their effect on alcohol consumption. We investigated alcohol use during lockdown in a population of college students, usually characterized by social and heavy drinking. We also tested the predictive role of pre-lockdown drinking motives on alcohol consumption during lockdown. We collected data from 1951 French-speaking Belgian students during the lockdown period (April 1st - May 3rd, 2020) through a cross-sectional online survey. Participants self-reported their daily alcohol consumption (1) during a typical week in normal circumstances (i.e., before lockdown), and (2) since lockdown onset. We also assessed drinking motives and severity of alcohol use before lockdown. Our findings showed that 68.2% of the sample reported a lower alcohol consumption during lockdown compared to before lockdown, 17.2% conversely reporting a higher consumption. Enhancement, social and coping motives were all associated with heavy drinking before lockdown. Enhancement and social motives predicted lower alcohol consumption during lockdown among heavy drinkers. Conversely, coping motives, as well as social motives among low drinkers, predicted higher consumption during lockdown. Conformity motives, as well as enhancement motives among low and moderate drinkers, did not predict alcohol consumption before or during lockdown. Overall, several pre-lockdown drinking motives reliably predicted alcohol consumption during lockdown and could thus be used to identify at-risk populations and to tailor intervention programs on alcohol misuse during sanitary crises.

Biopreservation represents a complementary approach to traditional hurdle technologies for reducing microbial contaminants (pathogens and spoilers) in food. In the dairy industry that is concerned by fungal spoilage, biopreservation can also be an alternative to preservatives currently used (e.g. natamycin, potassium sorbate). The aim of this study was to develop antifungal fermentates derived from two dairy substrates using a sequential approach including an in vitro screening followed by an in situ validation. The in vitro screening of the antifungal activity of fermentates derivating from 430 lactic acid bacteria (LAB) (23 species), 70 propionibacteria (4 species) and 198 fungi (87 species) was performed against four major spoilage fungi (Penicillium commune, Mucor racemosus, Galactomyces geotrichum and Yarrowia lipolytica) using a cheese-mimicking model. The most active fermentates were obtained from Lactobacillus brevis, Lactobacillus buchneri, Lactobacillus casei/paracasei and Lactobacillus plantarum among the tested LAB, Propionibacterium jensenii among propionibacteria, and Mucor lanceolatus among the tested fungi. Then, for the 11 most active fermentates, culture conditions were optimized by varying incubation time and temperature in order to enhance their antifungal activity. Finally, the antifungal activity of 3 fermentates of interest obtained from Lactobacillus rhamnosus CIRM-BIA1952, P. jensenii CIRM-BIA1774 and M. lanceolatus UBOCC-A-109193 were evaluated in real dairy products (sour cream and semi-hard cheese) at a pilot-scale using challenge and durability tests. In parallel, the impact of these ingredients on organoleptic properties of the obtained products was also assessed. In semi-hard cheese, application of the selected fermentates on the cheese surface delayed the growth of spoilage molds for up to 21 days, without any effect on organoleptic properties, P. jensenii CIRM-BIA1774 fermentate being the most active. In sour cream, incorporation of the latter fermentate at 2 or 5% yielded a high antifungal activity but was detrimental to the product organoleptic properties. Determination of the concentration limit, compatible with product acceptability, showed that incorporation of this fermentate at 0.4% prevented growth of fungal contaminants in durability tests but had a more limited effect against M. racemosus and P. commune in challenge tests. To our knowledge, this is the first time that the workflow followed in this study, from in vitro screening using dairy matrix to scale-up in cheese and sour cream, is applied for production of natural ingredients relying on a large microbial diversity in terms of species and strains. This approach allowed obtaining several antifungal fermentates which are promising candidates for dairy products biopreservation.

– Cantal is the third French Protected Denomination of Origin cheese. The Cantal cheesemaking process is similar to Cheddar cheese. Both processes involve a milling and a dry salting step which results in a homogeneous salted curd. In order to determine the key parameters of the manufacturing process acting on the specific characteristics of this cheese variety, an extensive and kinetic study repeated three times was carried out at nine stages from the raw milk to 120 d ripened cheese. The microbial ecosystem was explored by numeration and by direct extraction of DNA and PCR-Temporal Temperature Gradient Electrophoresis. Lysis of the lactic acid bacteria was checked by quantification of the intracellular lactate dehydrogenase activity. Carbon sources changes, solubilisation of minerals, proteolysis, lipolysis, and formation of neutral volatile compounds were also assessed. Cheese microstructure modifications and bacterial localisation were determined by confocal scanning laser microscopy. The controlled manufacturing conditions and the use of a complex mixture of starters led to very similar ripened cheeses. The compositional attributes (in particular total solids, fat, nitrogen forms), the lipolysis (0.7 ± 0.2% fat) and proteolysis final extent (34.4 g·kg–1 free amino acids in juice) were similar as well as major neutral volatiles compounds (2-butanone, ethanol and 2-butanol). Nevertheless, lactose and citrate metabolisms differed between the three trials and some free amino acids (Arg, Pro, Ser, Cit, Homocys) concentrations varied drastically during the ripening time course. CLSM micrographs showed that fat globules were disrupted during pressing and bacteria were preferentially localised at the fat/protein interface. As the lactic starter species were the same in the three trials and predominant during the cheese manufacture, the observed differences could result of one or several of the followings: (i) the raw milk microflora which showed to be different leading to growth or metabolism activity of particular subdominant populations during the process and the ripening; (ii) the more or less early lysis of the lactic starters; (iii) the possible interactions between raw milk microflora and the added starters. This extensive characterization of Cantal cheese provides a strong basis for building a rational concept of the key steps in which either technological actions or complementary microbial inoculation could be done in order to limit day to day variations.; Le fromage de Cantal est, en tonnage, la 3ème Appellation d'Origine Contrôlée française. Son procédé de fabrication, similaire à celui du Cheddar, implique une étape de broyage et salage à sec, qui résulte en un caillé salé homogène. Afin de déterminer les paramètres clé du procédé de fabrication agissant sur les caractéristiques spécifiques de cette variété de fromage, une étude approfondie et cinétique avec trois répétitions a été menée à 9 stades, du lait cru au fromage affiné 120 jours. L'écosystème microbien a été exploré par énumération et par extraction directe de l'ADN et PCR-Temporal Temperature Gradient Electrophoresis. La lyse des bactéries lactiques a été appréhendée par mesure de l'activité de la lactate déshydrogénase intracellulaire. Les changements intervenant dans les sources carbonées, la solubilisation des minéraux, la protéolyse, la lipolyse et l'apparition des composés volatiles neutres ont aussi été évalués. Les modifications de la microstructure du fromage ainsi que la localisation des bactéries ont été déterminées pas microscopie confocale à balayage laser (CLSM). La mise en oeuvre de conditions de fabrication très contrôlées et l'utilisation d'un levain complexe a conduit à des fromages affinés très similaires, tant sur le plan de la composition (en particulier l'extrait sec total, la matière grasse, les formes azotées) des niveaux de lipolyse (0.7 ± 0.2 % de la matière grasse) et de protéolyse (34,4 g·kg-1 d'acides aminés libres dans le jus) que sur le plan des teneurs en composés volatiles majoritaires (2-butanone, éthanol et 2-butanol). Néanmoins, les métabolismes du lactose et du citrate différaient entre les trois essais, ainsi que les concentrations en certains acides aminés libres (Arg, Pro, Ser, Cit, Homocys) qui variaient fortement au cours de l'affinage. Les photographies obtenues par CLSM montraient que les globules gras étaient brisés lors du pressage et que les bactéries étaient préférentiellement localisées à l'interface matière grasse/protéine. Comme le levain utilisé comportaient les mêmes espèces pour les trois essais et que celles-ci s'avéraient dominantes au cours de la fabrication, les différences observées peuvent résulter : (i) des variations observées dans la flore indigène du lait cru conduisant à la croissance ou l'activité métabolique de populations sous-dominantes particulières pendant la fabrication ou l'affinage ; (ii) de la lyse plus ou moins précoce des espèces du levain ; (iii) des interactions possibles entre la flore indigène du lait cru et le levain ajouté. Cette caractérisation approfondie du fromage Cantal offre une base solide pour construire un concept rationnel des étapes-clé au cours desquelles soit des actions technologiques, soit une inoculation microbienne complémentaire peuvent être réalisées afin de limiter les variations journalières et d'optimiser la qualité globale.

Past studies have suggested that the neuropeptide oxytocin (OT) could play a crucial role in human trusting behavior. Specifically, people on OT would be more willing to entrust someone with their money than would people on a placebo. Because alternative explanations-which do not involve trust-exist for these studies' findings, the present study aimed to rule out confounds and test how OT influences trust behavior in a totally different context. The variable at stake was not money but confidential information. Sixty participants were randomly assigned to receive either OT or a placebo. Results showed that oxytocin does increase trust, and that its effects extend beyond money. Specifically, participants on OT were 44 times more trusting that their privacy would not be violated than participants on placebo.

Indigenous yeasts can be detected at high populations in raw milk Cantal cheese, a French Protected Denomination of Origin (PDO) hard cheese. To investigate their use as adjunct cultures to promote flavour development in Cantalet (small Cantal) cheese, three strains isolated from raw milk Cantal cheese, Kluyveromyces lactis, Yarrowia lipolytica, and Pichia fermentans were added at 3 (E3) and 5 (E5) log(10) colony-forming units (cfu)/mL to microfiltered milk at a ratio of 80/10/10 viable cells, respectively. The global microbial, compositional and biochemical changes induced by the presence of yeasts in cheese were determined. Adjunct yeasts did not grow but stayed at viable populations of approximately 4 and 6 log(10) cfu/g in E3 and E5 cheeses, respectively, throughout the ripening period. They were mainly constituted of K. lactis, while P. fermentans and Y. lipolytica were not detectable after 3 and 45 days of ripening, respectively. Several species of indigenous yeasts were also detected in E3 cheeses at the beginning of ripening only, and in the control cheeses without yeasts added. Lactoccoci survived for longer periods in the presence of yeast adjuncts, while, conversely, the viability of Streptococcus thermophilus decreased more rapidly. The addition of yeasts did not influence cheese composition and total free amino acid content. In contrast, it slightly increased lipolysis in both E3 and E5 cheeses and markedly enhanced the formation of some volatile aroma compounds. The concentrations of ethanol, ethyl esters and some branched-chain alcohols were 6 to 10 fold higher in E5 cheeses than in the control cheeses, and only slightly higher in E3 cheeses. This study shows that K. lactis has a potential as cheese adjunct culture in Cantalet cheese and that, added at populations of 4-5 log(10) cfu/g cheese, it enhances the formation of flavour compounds.

Yeasts are commonly detected in cheese. Two yeast species, Kluyveromyces lactis and Pichia fermentans, were isolated at high populations from raw-milk Cantalet cheese, a French Protected Denomination of Origin hard cheese. To investigate the interest of these 2 species as adjunct cultures to promote flavor development of Cantalet cheese, they were added at 10(5) cfu/mL to microfiltered milk. The global microbiological, biochemical, and flavor changes induced by the presence of the yeasts in cheese were determined. Adjunct yeasts were present at 10(6) cfu/g in curd, declined to 10(4) to 10(5) cfu/g in cheese, and did not influence gross composition, content of free amino acids, or content of free fatty acids. By using 8-way gas chromatography-olfactometry in parallel with gas chromatography-mass spectrometry, 30 odorous compounds of Cantalet cheese were identified. The olfactory profiles of K. lactis cheeses contained significantly greater levels of 8 odorous compounds (ethanol, ethyl hexanoate, 4 aldehydes, and 2 branched-chain acids) compared with the control and P. fermentans cheeses. Sensory analysis of cheeses flavor discriminated K. lactis cheeses on only 2 attributes (acetaldehyde and alcohol odors). This study shows that yeast contribution is species-specific and that K. lactis, at a population of 10(6) viable cells/g, can influence Cantalet cheese flavor.

In spite of its high production (18000 T yearly), very few studies have been devoted to Cantal, a French AOC ("Appellation d'Origine Contrôlée") cheese variety whose making process is close to that of Cheddar. To improve the knowledge of this type of cheese, two ripened Cantal cheeses issued from raw milk and two different industrial processes were biochemically, physicochemically, structurally and microbiologically characterised through the analysis of both cheese sectors and juices extracted by pressure. The results obtained were compared with Cheddar and Emmental cheeses. The main differences between Cheddar and Cantal cheeses of the same age were a higher rate of proteolysis for Cantal cheese shown by both the total nitrogen content and the TCA soluble nitrogen in the respective cheese juices, and higher CaT content as well as an increased molar CaT/PT ratio in the Cantal cheese. Free amino contents in the cheese aqueous phase were similar but individual variations suggested an effect of the secondary ripening microflora provided by the raw milk used. Microbial counts done on different media showed a dominant mesophilic and thermophilic lactic acid bacteria flora, a subdominant flora composed of various ripening bacteria and yeasts and a very low level of some coliforms and of Pseudomonas. An amount of 44 neutral volatile compounds were identified but 3 of them determined by GC-MS (ethanol, 2-butanone and 2-butanol) represented more than 95% of the total peak area. Some variations in these main compounds as well as in minor ones confirmed a difference in the native microflora in the two studied Cantal cheeses. Nevertheless, these data appeared in the range of those reported for Cheddar. The microstructure of fat determined by confocal laser scanning micrography showed that little is present in Cantal cheese as intact fat globules. Most of this component appeared as free fat included in the casein matrix with a high ability to oil off, especially the part which is near the crust. As well as offering a precise characterisation of many compositional aspects of ripened Cantal cheese, this study opens the way for further works on the process kinetics carried out in the making processes and for a better knowledge of the ecosystem metabolism., Microstructure, physico-chimie, flore microbienne et composés aromatiques du fromage de Cantal affiné. En dépit de sa production élevée (18 000 T/an), peu d'études ont été consacrées au Cantal (3e Appellation d'Origine Contrôlée française) dont le procédé de fabrication peut être rapproché de celui du Cheddar. Pour accroître les connaissances sur cette variété de fromage, deux fromages Cantal affinés, obtenus à partir de lait cru, selon deux procédés de fabrication ont été caractérisés analytiquement au plan biochimique, physico-chimique, microbiologique et microstructural, à la fois par l'analyse des fromages et de leurs jus respectifs obtenus par extraction sous pression. Les résultats obtenus ont été comparés aux données existantes sur le Cheddar et l'Emmental. Les principales différences mises en évidence entre Cantal et Cheddar concernent le niveau de protéolyse (teneurs en N × 6,38 et proportion de N soluble dans le TCA accrues par rapport aux jus extraits de Cheddar), une teneur en CaT ainsi qu'un rapport molaire CaT/PT plus élevés dans le Cantal. Si la teneur en acides aminés libres ne différait globalement pas de celle décrite pour le Cheddar, les variations déterminées au niveau individuel suggéraient que l'activité métabolique de la microflore d'affinage (probablement apportée par le lait cru mis en œuvre) était différente entre les deux Cantal étudiés. Les déterminations microbiologiques effectuées à l'aide de différents milieux de culture montraient que la flore était principalement constituée de bactéries lactiques mésophiles et thermophiles. Toutefois, une microflore d'affinage très variée (probablement, propionibacteria, corynebacteria, staphylocoques et microcoques ainsi que des levures), à des niveaux de 104 à 105 ufc*g-1 a pu être identifiée et comparée aux quelques données existantes de la littérature. Une très faible teneur en bactéries indésirables (coliformes et Pseudomonas) a également été dénombrée. Un total de 44 composés volatils neutres ont été caractérisés mais comme pour de nombreuses autres variétés fromagères incluant le Cheddar, trois d'entre eux (éthanol, 2-butanone et 2-butanol) représentent plus de 95 % de l'aire totale des pics déterminés par chromatographie gazeuse couplée à la spectrométrie de masse. La comparaison détaillée des teneurs en composés volatils des deux Cantal étudiés confirmaient la différence d'activité métabolique de la microflore native des laits mis respectivement en fabrication. L'analyse de la microstructure des fromages par microscopie confocale à laser, montrait que l'essentiel de la matière grasse du Cantal se trouvait sous forme non structurée en globules mais bien sous forme d'amas de taille variable ayant une propension aisée à s'extraire de la matrice caséique, et ce particulièrement pour la matière grasse voisine de la croûte du fromage. Les résultats obtenus précisent sur de nombreux aspects les paramètres de composition du Cantal affiné. Ils ouvrent également la voie à de nouveaux travaux tant sur les cinétiques d'obtention mises en œuvre au cours du procédé de fabrication de ces paramètres que sur une meilleure connaissance du métabolisme de l'écosystème d'acidification et d'affinage.