Disappointment Models: an axiomatic approach

URL des Documents de travail : http://ces.univ-paris1.fr/cesdp/cesdp2011.htmlDocuments de travail du Centre d'Economie de la Sorbonne 2010.102 - ISSN : 1955-611X - Version originale Décembre 2010, révisée en Mai et Décembre 2011In this paper, a fully choice-based theory of disappointment is developed. It encompasses, as particular cases, EU theory, Gul's theory of disappointment (1991) and the models of Loomes and Sugden (1986). According to the new theory, the risk premium of a random prospect is the sum of two premiums: a concavity premium that is nothing but the usual Arrow-Pratt premium and a second premium that may be identified to expected disappointment. The corresponding representing functional belongs to the class of lottery-dependent utility models (Becker and Sarin 1987) since disappointment is the deficit between the utility of the realized outcome and its expected value. However, unlike the lottery-dependent approach, the theory is choice-based and its axioms are experimentally testable.Nous proposons, dans cette étude, une axiomatisation du comportement d'un individu en univers incertain. Cette axiomatisation permet d'effectuer une synthèse de nombreuses théories antérieures : théorie de l'utilité espérée, théorie de la déception (Gul 1991), modèles à la Loomes et Sugden (1986) ou modèles à fonctionnelle "loterie-dépendante" (Becker and Sarin 1987). La prime de risque exigée par un investisseur y est la somme d'une prime d'Arrow-Pratt et d'une seconde prime, égale à l'espérance de la déception. Celle-ci n'est autre que la différence entre la satisfaction éprouvée ex ante et l'utilité espérée du revenu aléatoire

Comparative functional genomics and the bovine macrophage response to strains of the Mycobacterium genus

Mycobacterial infections are major causes of morbidity and mortality in cattle and are also potential zoonotic agents with implications for human health. Despite the implementation of comprehensive animal surveillance programs, many mycobacterial diseases have remained recalcitrant to eradication in several industrialized countries. Two major mycobacterial pathogens of cattle are Mycobacterium bovis and Mycobacterium avium subspecies paratuberculosis (MAP), the causative agents of bovine tuberculosis (BTB) and Johne's disease (JD), respectively. BTB is a chronic, granulomatous disease of the respiratory tract that is spread via aerosol transmission, while JD is a chronic granulomatous disease of the intestines that is transmitted via the fecal-oral route. Although these diseases exhibit differential tissue tropism and distinct complex etiologies, both M. bovis and MAP infect, reside, and replicate in host macrophages - the key host innate immune cell that encounters mycobacterial pathogens after initial exposure and mediates the subsequent immune response. The persistence of M. bovis and MAP in macrophages relies on a diverse series of immunomodulatory mechanisms, including the inhibition of phagosome maturation and apoptosis, generation of cytokine-induced necrosis enabling dissemination of infection through the host, local pathology, and ultimately shedding of the pathogen. Here, we review the bovine macrophage response to infection with M. bovis and MAP. In particular, we describe how recent advances in functional genomics are shedding light on the host macrophage-pathogen interactions that underlie different mycobacterial diseases. To illustrate this, we present new analyses of previously published bovine macrophage transcriptomics data following in vitro infection with virulent M. bovis, the attenuated vaccine strain M. bovis BCG, and MAP, and discuss our findings with respect to the differing etiologies of BTB and JD

Argentine tango: Another behavioral addiction?

Background: Behavioral addiction is an emerging concept based on the resemblance between symptoms or feelings provided by drugs and those obtained with various behaviors such as gambling, etc. Following an observational study of a tango dancer exhibiting criteria of dependence on this dance, we performed a survey to assess whether this case was unique or frequently encountered in the tango dancing community. Methods: We designed an online survey based on both the DSM-IV and Goodman's criteria of dependence; we added questions relative to the positive and negative effects of tango dancing and a self-evaluation of the degree of addiction to tango. The questionnaire was sent via Internet to all the tango dancers subscribing to “ToutTango”, an electronic monthly journal. The prevalence of dependence was analyzed using DSM-IV, Goodman's criteria and self-rating scores separately. Results: 1,129 tango dancers answered the questionnaire. Dependence rates were 45.1, 6.9 and 35.9%, respectively, according to the DSM-IV, Goodman's criteria and self-rating scores. Physical symptoms of withdrawal were reported by 20% of the entire sample and one-third described a strong craving for dancing. Positive effects were high both in dependent and non-dependent groups and were markedly greater than negative effects. Long practice of tango dancing did not modify the dependence rate or reduce the level of positive effects. Conclusions: Tango dancing could lead to dependence as currently defined. However, this dependence is associated with marked and sustained positive effects whilst the negative are few. Identifying the precise substratum of this dependence needs further investigation

Disappointment Models : an axiomatic approach

In this paper, a fully choice-based theory of disappointment is developed. It encompasses, as particular cases, EU theory, Gul's theory of disappointment (1991) and the models of Loomes and Sugden (1986). According to the new theory, the risk premium of a random prospect is the sum of two premiums : a concavity premium that is nothing but the usual Arrow-Pratt premium and a second premium that may be identified to expected disappointment. The corresponding representing functional belongs to the class of lottery-dependent utility models (Becker and Sarin 1987) since disappointment is the deficit between the utility of the realized outcome and its expected value. However, unlike the lottery-dependent approach, the theory is choice-based and its axioms are experimentally testable.Axiomatization ; disappointment aversion ; random prospect ; risk premium ; expected utility.

Multidetachment analogue models of fold reactivation in transpression : the NW Persian Gulf

Two deformation events have been documented in the NW Persian Gulf during the Late Cretaceous and the Late Cenozoic. The most distinctive feature in this part of the Persian Gulf is the reactivation of the Late Cretaceous NNE-SSW Arabian trending folds by NE-SW shortening during the Late Cenozoic Zagros orogeny. In general, if a set of folds with horizontal axes is shortened roughly parallel to its fold axis, a dome-basin fold interference pattern is produced. In the NW Persian Gulf, reactivation of some old folds occurred instead of a fold interference pattern. Reactivation may be influenced by the following factors: i) the presence of incompetent layers (i.e. evaporites), ii) a variable overburden, iii) basement faults, and iv) obliquity between the younger deformation shortening axis and fold axis. It is this last factor that we investigated by means of analogue modelling. The experimental apparatus is similar to that commonly used for experiments with brittle-ductile systems at the Laboratory of Experimental Tectonics of Géosciences Rennes. The model consisted of an alternation of ductile and brittle horizontal layers with a stratigraphy similar to the one found in the NW Persian Gulf. The model was deformed by two deformation events with an angle a between the two directions of shortening. After deformation, the resulting structure resembled a fold facing the static wall with internal thrust faults and detachment faults arranged into a geometry similar to a fish tail. In the second shortening event, the fold was reactivated without formation of an interference pattern. Moreover, the displacement on both the reactivated and newly formed faults varied between almost pure thrust faults for low a and oblique thrust faults with a strike-slip component for high a. The models suggest that the presence of incompetent layers plays an important role in fold reactivation and confirm that basement faults are not necessary

GOexpress: an R/Bioconductor package for the identification and visualisation of robust gene ontology signatures through supervised learning of gene expression data

Background: Identification of gene expression profiles that differentiate experimental groups is critical for discovery and analysis of key molecular pathways and also for selection of robust diagnostic or prognostic biomarkers. While integration of differential expression statistics has been used to refine gene set enrichment analyses, such approaches are typically limited to single gene lists resulting from simple two-group comparisons or time-series analyses. In contrast, functional class scoring and machine learning approaches provide powerful alternative methods to leverage molecular measurements for pathway analyses, and to compare continuous and multi-level categorical factors. Results: We introduce GOexpress, a software package for scoring and summarising the capacity of gene ontology features to simultaneously classify samples from multiple experimental groups. GOexpress integrates normalised gene expression data (e.g., from microarray and RNA-seq experiments) and phenotypic information of individual samples with gene ontology annotations to derive a ranking of genes and gene ontology terms using a supervised learning approach. The default random forest algorithm allows interactions between all experimental factors, and competitive scoring of expressed genes to evaluate their relative importance in classifying predefined groups of samples. Conclusions: GOexpress enables rapid identification and visualisation of ontology-related gene panels that robustly classify groups of samples and supports both categorical (e.g., infection status, treatment) and continuous (e.g., time-series, drug concentrations) experimental factors. The use of standard Bioconductor extension packages and publicly available gene ontology annotations facilitates straightforward integration of GOexpress within existing computational biology pipelines.Department of Agriculture, Food and the MarineEuropean Commission - Seventh Framework Programme (FP7)Science Foundation IrelandUniversity College Dubli

Effects of margin-parallel shortening and density contrasts on back-arc extension during subduction: Experimental insights and possible application to Anatolia

International audienceSo as to investigate the parameters influencing subduction and back-arc extension, we have done three series of laboratory experiments (32 in all) on physical models. Each model consisted of adjacent oceanic and continental plates, floating on an asthenosphere. In experiments of Series A, a wide rigid piston, moving horizontally, controlled the rate of convergence of the oceanic and continental plates, whereas, in Series B or C, a wide or narrow piston produced lateral compression, parallel to the continent-ocean boundary (COB) and perpendicular to the subduction direction. The parameters that we tested were (1) the velocity of plate convergence (Series A), (2) the width of the compressing piston (Series B and C), and (3) the density ratio between oceanic and continental plates (Series B and C). This density ratio was a key factor. For a ratio of 1.4, the amount of extension in the continental plate increased regularly throughout time; for a ratio of 1.3, the extension remained small, until the piston stopped moving laterally; and for a ratio of 1.1, there was little or no extension. The width of the compressing piston had a smaller effect, although a narrow piston provided more space, into which the continental plate could extend. One possible application of our models is to Anatolia. Despite similar geological settings, the areas north of the Hellenic and Cyprus subduction zones differ, in that extension is large in the former and much smaller in the latter. We suggest that one of the main driving forces for Aegean extension may have been a high density ratio between subducting oceanic lithosphere and a Hellenic-Balkanic upper plate

RNA-seq transcriptional profiling of peripheral blood leukocytes from cattle infected with Mycobacterium bovis

Bovine tuberculosis, caused by infection with Mycobacterium bovis, is a major endemic disease affecting cattle populations worldwide, despite the implementation of stringent surveillance and control programs in many countries. The development of high-throughput functional genomics technologies, including gene expression microarrays and RNA-sequencing (RNA-seq), has enabled detailed analysis of the host transcriptome to M. bovis infection, particularly at the macrophage and peripheral blood level. In the present study, we have analyzed the peripheral blood leukocyte (PBL) transcriptome of eight natural M. bovis-infected and eight age- and sex-matched non-infected control Holstein-Friesian animals using RNA-seq. In addition, we compared gene expression profiles generated using RNA-seq with those previously generated using the high-density Affymetrix(®) GeneChip(®) Bovine Genome Array platform from the same PBL-extracted RNA. A total of 3,250 differentially expressed (DE) annotated genes were detected in the M. bovis-infected samples relative to the controls (adjusted P-value ≤0.05), with the number of genes displaying decreased relative expression (1,671) exceeding those with increased relative expression (1,579). Ingenuity(®) Systems Pathway Analysis (IPA) of all DE genes revealed enrichment for genes with immune function. Notably, transcriptional suppression was observed among several of the top-ranking canonical pathways including Leukocyte Extravasation Signaling. Comparative platform analysis demonstrated that RNA-seq detected a larger number of annotated DE genes (3,250) relative to the microarray (1,398), of which 917 genes were common to both technologies and displayed the same direction of expression. Finally, we show that RNA-seq had an increased dynamic range compared to the microarray for estimating differential gene expression

Whole-transcriptome, high-throughput RNA sequence analysis of the bovine macrophage response to Mycobacterium bovis infection in vitro

BACKGROUND: Mycobacterium bovis, the causative agent of bovine tuberculosis, is an intracellular pathogen that can persist inside host macrophages during infection via a diverse range of mechanisms that subvert the host immune response. In the current study, we have analysed and compared the transcriptomes of M. bovis-infected monocyte-derived macrophages (MDM) purified from six Holstein-Friesian females with the transcriptomes of non-infected control MDM from the same animals over a 24 h period using strand-specific RNA sequencing (RNA-seq). In addition, we compare gene expression profiles generated using RNA-seq with those previously generated by us using the high-density Affymetrix® GeneChip® Bovine Genome Array platform from the same MDM-extracted RNA. RESULTS: A mean of 7.2 million reads from each MDM sample mapped uniquely and unambiguously to single Bos taurus reference genome locations. Analysis of these mapped reads showed 2,584 genes (1,392 upregulated; 1,192 downregulated) and 757 putative natural antisense transcripts (558 upregulated; 119 downregulated) that were differentially expressed based on sense and antisense strand data, respectively (adjusted P-value ≤ 0.05). Of the differentially expressed genes, 694 were common to both the sense and antisense data sets, with the direction of expression (i.e. up- or downregulation) positively correlated for 693 genes and negatively correlated for the remaining gene. Gene ontology analysis of the differentially expressed genes revealed an enrichment of immune, apoptotic and cell signalling genes. Notably, the number of differentially expressed genes identified from RNA-seq sense strand analysis was greater than the number of differentially expressed genes detected from microarray analysis (2,584 genes versus 2,015 genes). Furthermore, our data reveal a greater dynamic range in the detection and quantification of gene transcripts for RNA-seq compared to microarray technology. CONCLUSIONS: This study highlights the value of RNA-seq in identifying novel immunomodulatory mechanisms that underlie host-mycobacterial pathogen interactions during infection, including possible complex post-transcriptional regulation of host gene expression involving antisense RNA

Clinical management methods for out-patients with alcohol dependence

BACKGROUND: In France outpatient centres for the care of alcoholics are healthcare establishments providing medical, psychological and social support. Although they meet the practical needs of these patients, their degree of use in each of these domains and the respective mobilisation of different skills by the care team are not well understood. Our aim was therefore to determine in detail the management involved as a function of the severity of alcohol dependence. For this purpose, all the procedures involved were compiled in a thesaurus describing its type (psychological, medical, social, reception), its scheduled or unscheduled nature, its method (face-to-face, telephone, letter) and its duration. The severity of dependence was evaluated using the Addiction Severity Index (ASI). RESULTS: 45 patients were included and followed-up during 291 ± 114 days. The mean initial ASI scores (± SD) were: medical (M) = 0.39 ± 0.3, working-income (ER) = 0.5 ± 0.3, alcohol (A) = 0.51 ± 0.2, illicit drugs (D) = 0.07 ± 0.08, legal (L) = 0.06 ± 0.13, familial and social environment (FS) = 0.34 ± 0.26, psychological (P) = 0.39 ± 0.22. The total number of procedures was 1341 (29.8 per patient) corresponding to 754.4 hours (16.7 per patient). The intensity of management peaked during the first month of treatment, and then declined rapidly; the maximum incidence of abstinence was observed during the 3rd month of management. Interviews with patients, group therapy and staff meetings represented 68.7%, 9.9% and 13.9% of all procedures, respectively. In patients with severe dependence, as compared to moderate, management was twice as intense in the psychological and social domains, but not in the medical domain. The ASI questionnaire was completed a second time by 24 patients, after an average of 3.2 months. The improvement was significant in the M, A, D and P domains only. CONCLUSION: This study provided an overview of the methods employed in managing a sample of patients consulting an alcoholism centre in line with standards for medical, psychological and social establishments. The predominance of the social and psychological domains over the medical domain was clearly established. Relapses were common after the third month of treatment, but a remobilisation of teams made it possible to contain them. These results provide a framework for discussions on the organisation of healthcare systems and highly suggest that staff need to maintain a constant level of care throughout the treatment process