Circuits neuronaux et comportement. Analyse génétique de traitement olfactif et fonction

Responsable : Alexander Fleischmann Recherche Notre laboratoire s’intéresse aux circuits neuronaux qui sous-tendent la perception des odeurs. Nous utilisons une combinaison d’approches expérimentales chez la souris, incluant génétique moléculaire, imagerie in vivo et analyse du comportement, pour comprendre la logique du codage de l’information sensorielle par les différents relais olfactifs du cerveau. La perception des odeurs repose d’une part sur la reconnaissance des divers composants odo..

Circuits neuronaux et comportement / Neural circuits and behavior

Recherche Page web : https://www.college-de-france.fr/site/en-cirb/fleischmann.htm

Keeping Software Users on Board - Increasing Continuance Intention Through Incremental Feature Updates

Although feature updates are a ubiquitous phenomenon in both professional and private IT usage, they have to date received little attention in the IS post-adoption literature. Drawing on expectation-confirmation theory and the IS continuance literature, we investigate whether, when and how incremental feature updates affect users’ continuance intentions (CI). Based on a controlled laboratory experiment, we find a positive effect of feature updates on users’ CI. According to this effect, software vendors can increase their users’ CI by delivering updates incrementally rather than providing the entire feature set right with the first release. However, we also find that CI diminishes when the number of updates exceeds a tipping point in a given timeframe, disclosing update frequency as crucial boundary condition. Furthermore, we unveil that the beneficial effect of feature updates on CI operates through positive disconfirmation of expectations, resulting in increased user satisfaction. Implications for research and practice as well as directions for future research are discussed

Gains and Losses in Functionality – An Experimental Investigation of the Effect of Software Updates on Users’ Continuance Intentions

Although software updates are ubiquitous in professional and private IS usage, their impact on user behaviors has received little attention in post-adoption research. Based on expectation-confirmation-theory and the IS continuance model, we investigate the effects of gaining and loosing features through updates on expert and novice users’ continuance intentions (CI). In a vignette based experiment, we find that updates which add features to software after its release increase novices’ CI above and beyond a level generated by a monolithic software package that contains the entire feature set from the beginning. With diminished CI, experts show a contrary reaction to the same update. Losing features through an update, on the other hand, severely diminishes CI for experts and novices alike. Mediation analysis reveals positive disconfirmation of previous expectations as psychological mechanism behind novices’ counter-intuitive and somewhat non-rational responses to gaining features through an update. Implications for research and practice are derived

Driving Opposing Behaviors with Ensembles of Piriform Neurons

SummaryAnatomic and physiologic studies have suggested a model in which neurons of the piriform cortex receive convergent input from random collections of glomeruli. In this model, odor representations can only be afforded behavioral significance upon experience. We have devised an experimental strategy that permits us to ask whether the activation of an arbitrarily chosen subpopulation of neurons in piriform cortex can elicit different behavioral responses dependent upon learning. Activation of a small subpopulation of piriform neurons expressing channelrhodopsin at multiple loci in the piriform cortex, when paired with reward or shock, elicits either appetitive or aversive behavior. Moreover, we demonstrate that different subpopulations of piriform neurons expressing ChR2 can be discriminated and independently entrained to elicit distinct behaviors. These observations demonstrate that the piriform cortex is sufficient to elicit learned behavioral outputs in the absence of sensory input. These data imply that the piriform does not use spatial order to map odorant identity or behavioral output.PaperCli

Arbeitstagung der Konferenz der Einrichtungen für Frauen- und Geschlechterstudien im deutschsprachigen Raum (KEG) 2015

Wrede B, Fleischmann A, Pache I, Rietmann T. Arbeitstagung der Konferenz der Einrichtungen für Frauen- und Geschlechterstudien im deutschsprachigen Raum (KEG) 2015. IFFOnZeit. Onlinezeitschrift des Interdisziplinären Zentrums für Frauen- und Geschlechterforschung (IFF). 2015;(4):67-73

The Use of Intraosseous Needles for Injection of Contrast Media for Computed Tomographic Angiography of the Thoracic Aorta

Background The objective of this study is to evaluate the safety and quality of computed tomographic angiography of the thoracic aorta (CTA-TA) exams performed using intraosseous needle intravenous access (ION-IVA) for contrast media injection (CMI). Methods All CTA-TA exams at the study institution performed between 1/1/2013 and 8/14/2015 were reviewed retrospectively to identify those exams which had been performed using ION-IVA (ION-exams). ION-exams were then analyzed to determine aortic attenuation and contrast-to-noise ratio (CNR). Linear regression was used to determine how injection rate and other variables affected image quality for ION-exams. Patient electronic medical records were reviewed to identify any adverse events related to CTA-TA or ION-IVA. Results 17 (∼0.2%) of 7401 exams were ION-exams. ION-exam CMI rates varied between 2.5 and 4 ml/s. Mean attenuation was 312 HU (SD 88 HU) and mean CNR was 25 (SD 9.9). A strong positive linear association between attenuation and injection rate was found. No immediate or delayed complications related to the ION-exams, or intraosseous needle use in general, occurred. Conclusion For CTA-TA, ION-IVA appears to be a safe and effective route for CMI at rates up to 4 ml/s

The Proteome Analysis database: a tool for the in silico analysis of whole proteomes

The Proteome Analysis database (http://www.ebi.ac.uk/proteome/) has been developed by the Sequence Database Group at EBI utilizing existing resources and providing comparative analysis of the predicted protein coding sequences of the complete genomes of bacteria, archeae and eukaryotes. Three main projects are used, InterPro, CluSTr and GO Slim, to give an overview on families, domains, sites, and functions of the proteins from each of the complete genomes. Complete proteome analysis is available for a total of 89 proteome sets. A specifically designed application enables InterPro proteome comparisons for any one proteome against any other one or more of the proteomes in the databas