Facts, Norms and Expected Utility Functions

In this paper we want to explore an argumentative pattern that provides a normative justification for expected utility functions grounded on empirical evidence, showing how it worked in three different episodes of their development. The argument claims that we should prudentially maximize our expected utility since this is the criterion effectively applied by those who are considered wisest in making risky choices (be it gamblers or businessmen). Yet, to justify the adoption of this rule, it should be proven that this is empirically true: i.e., that a given function allows us to predict the choices of that particular class of agents. We show how expected utility functions were introduced and contested in accordance to this pattern in the 18th century and how it recurred in the 1950s when M. Allais made his case against the neobernoullians.Expected utility;Normative theory;

Influence of water on the circulation of the West Nile Virus in horses in Southern France

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Fungicide-Driven Evolution and Molecular Basis of Multidrug Resistance in Field Populations of the Grey Mould Fungus Botrytis cinerea

The grey mould fungus Botrytis cinerea causes losses of commercially important fruits, vegetables and ornamentals worldwide. Fungicide treatments are effective for disease control, but bear the risk of resistance development. The major resistance mechanism in fungi is target protein modification resulting in reduced drug binding. Multiple drug resistance (MDR) caused by increased efflux activity is common in human pathogenic microbes, but rarely described for plant pathogens. Annual monitoring for fungicide resistance in field isolates from fungicide-treated vineyards in France and Germany revealed a rapidly increasing appearance of B. cinerea field populations with three distinct MDR phenotypes. All MDR strains showed increased fungicide efflux activity and overexpression of efflux transporter genes. Similar to clinical MDR isolates of Candida yeasts that are due to transcription factor mutations, all MDR1 strains were shown to harbor activating mutations in a transcription factor (Mrr1) that controls the gene encoding ABC transporter AtrB. MDR2 strains had undergone a unique rearrangement in the promoter region of the major facilitator superfamily transporter gene mfsM2, induced by insertion of a retrotransposon-derived sequence. MDR2 strains carrying the same rearranged mfsM2 allele have probably migrated from French to German wine-growing regions. The roles of atrB, mrr1 and mfsM2 were proven by the phenotypes of knock-out and overexpression mutants. As confirmed by sexual crosses, combinations of mrr1 and mfsM2 mutations lead to MDR3 strains with higher broad-spectrum resistance. An MDR3 strain was shown in field experiments to be selected against sensitive strains by fungicide treatments. Our data document for the first time the rising prevalence, spread and molecular basis of MDR populations in a major plant pathogen in agricultural environments. These populations will increase the risk of grey mould rot and hamper the effectiveness of current strategies for fungicide resistance management

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M>70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0<e≤0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Circulation enzootique du virus West Nile en population équine : identification de facteurs de risque environnementaux en Camargue, France

Our objective was to assess risk of endemic circulation of the West Nile Virus (WNV) in horses in Camargue, where WNV caused several outbreaks (1962, 2000 and 2004). Epidemiology of WN disease is much complex, due to the great number of vector and host species potentially involved. Mainly transmitted by vectors, WNV circulation is deeply influenced by environmental factors. Horses were chosen as indicator of WNV circulation, because they are particularly sensitive to infection by this virus. The method applied in our studies is based on the use of direct link between environment and endemic circulation of WNV, by studying seropositivity in horses (IgG). In the first two studies, some environmental risk factors have been identified, such as land cover classes (heterogeneous agricultural areas, flooded vegetation) or landscape metrics (Interspersion and Juxtaposition Index). Risk map of endemic WNV circulation were computed for French Mediterranean coast. Individual risk factors, like breed, age and activity of horses were also identified. In the third study, WNV transmission processes in Camargue were assessed. In the study region, WNV would be introduced by migrating birds and amplified by Culex modestus and many competent bird species. Dilution effect would have no impact on WNV amplification in Camargue. WNV would be transmitted to horses by both C. modestus and C. pipiens. Our results could permit to target monitoring of this disease in France and apply control measures well adapted to local conditions.L'objectif était d'évaluer le risque de circulation enzootique du virus West Nile (WN) chez le cheval en Camargue, région dans laquelle ce virus a déjà causé plusieurs épizooties. L'épidémiologie de la maladie de WN est très complexe, du fait de l'implication potentielle d'un grand nombre d'espèces de vecteurs et d'hôtes. De par sa transmission principalement vectorielle, la circulation du virus WN est fortement influencée par des facteurs environnementaux. L'espèce équine a été choisie comme témoin de la circulation du virus WN, car le cheval est particulièrement sensible à l'infection par ce virus. La méthode appliquée est basée sur l'utilisation du lien direct existant entre l'environnement et la circulation enzootique du virus WN, par l'étude de la séropositivité (IgG) chez le cheval. Dans les deux premières études présentées, certains facteurs de risque environnementaux ont été identifiés, comme des classes d'occupation du sol (zones agricoles hétérogènes, végétation inondée) ou des indices de paysage (Indice d'Imbrication et de Juxtaposition), ayant conduit à l'élaboration d'une carte de risque pour cette circulation dans le bassin méditerranéen français. Des facteurs de risque individuels, comme la race, l'âge et l'activité du cheval, ont également été identifiés. Dans la troisième étude présentée, des hypothèses de transmission du virus en Camargue ont été testées. Dans la région d'étude, le virus serait introduit par les oiseaux migrateurs et amplifié par Culex modestus et plusieurs espèces d'oiseaux compétentes. L'effet de dilution n'aurait pas d'impact sur l'amplification du virus en Camargue. Le virus serait transmis au cheval par C. modestus et C. pipiens

Circulation enzootique du virus West Nile en population équine : identification de facteurs de risque environnementaux en Camargue, France

Our objective was to assess risk of endemic circulation of the West Nile Virus (WNV) in horses in Camargue, where WNV caused several outbreaks (1962, 2000 and 2004). Epidemiology of WN disease is much complex, due to the great number of vector and host species potentially involved. Mainly transmitted by vectors, WNV circulation is deeply influenced by environmental factors. Horses were chosen as indicator of WNV circulation, because they are particularly sensitive to infection by this virus. The method applied in our studies is based on the use of direct link between environment and endemic circulation of WNV, by studying seropositivity in horses (IgG). In the first two studies, some environmental risk factors have been identified, such as land cover classes (heterogeneous agricultural areas, flooded vegetation) or landscape metrics (Interspersion and Juxtaposition Index). Risk map of endemic WNV circulation were computed for French Mediterranean coast. Individual risk factors, like breed, age and activity of horses were also identified. In the third study, WNV transmission processes in Camargue were assessed. In the study region, WNV would be introduced by migrating birds and amplified by Culex modestus and many competent bird species. Dilution effect would have no impact on WNV amplification in Camargue. WNV would be transmitted to horses by both C. modestus and C. pipiens. Our results could permit to target monitoring of this disease in France and apply control measures well adapted to local conditions.L'objectif était d'évaluer le risque de circulation enzootique du virus West Nile (WN) chez le cheval en Camargue, région dans laquelle ce virus a déjà causé plusieurs épizooties. L'épidémiologie de la maladie de WN est très complexe, du fait de l'implication potentielle d'un grand nombre d'espèces de vecteurs et d'hôtes. De par sa transmission principalement vectorielle, la circulation du virus WN est fortement influencée par des facteurs environnementaux. L'espèce équine a été choisie comme témoin de la circulation du virus WN, car le cheval est particulièrement sensible à l'infection par ce virus. La méthode appliquée est basée sur l'utilisation du lien direct existant entre l'environnement et la circulation enzootique du virus WN, par l'étude de la séropositivité (IgG) chez le cheval. Dans les deux premières études présentées, certains facteurs de risque environnementaux ont été identifiés, comme des classes d'occupation du sol (zones agricoles hétérogènes, végétation inondée) ou des indices de paysage (Indice d'Imbrication et de Juxtaposition), ayant conduit à l'élaboration d'une carte de risque pour cette circulation dans le bassin méditerranéen français. Des facteurs de risque individuels, comme la race, l'âge et l'activité du cheval, ont également été identifiés. Dans la troisième étude présentée, des hypothèses de transmission du virus en Camargue ont été testées. Dans la région d'étude, le virus serait introduit par les oiseaux migrateurs et amplifié par Culex modestus et plusieurs espèces d'oiseaux compétentes. L'effet de dilution n'aurait pas d'impact sur l'amplification du virus en Camargue. Le virus serait transmis au cheval par C. modestus et C. pipiens

Importance of Wetlands Management for West Nile Virus Circulation Risk, Camargue, Southern France

To assess environmental and horse-level risk factors associated with West Nile Virus (WNV) circulation in Camargue, Southern France, a serosurvey was conducted on non-vaccinated horses (n = 1159 from 134 stables) in 2007 and 2008. Fifteen Landsat images were examined to quantify areas with open water and flooded vegetation around sampled horses. Mean percentages of areas of open water and flooded vegetation, as well as variations in these percentages between 3 periods (November to February = NOT, March to July = END and August to October = EPI), were calculated for buffers of 2 km radius around the stables. Results of the final logistic regression showed that the risk of WNV seropositivity in horses decreased with their date of acquisition and age. Results also demonstrated the significant role of environmental variables. Horse serological status was associated with variations of open water areas between the NOT (November to February) and END (March to July) periods, as well as between END and EPI (August to October). WNV spillover was found more intense in areas where water level decreased strongly from winter to spring and from spring to summer