Impact of the drought on the fodder self-sufficiency of organic and conventional highland dairy farms

Eight highland dairy farms in the French Massif Central (4 organic and 4 conventional) were surveyed from 2000 to 2005 to understand the forage system functioning and the specificities of organic farms. During this period two important droughts occurred, which highly affected the fodder self-sufficiency of the organic farms, having consequences on more than a year of production. The conventional farms were less affected than the organic ones, and the farmers developed varied strategies including a reduction of the LU and the use of more maize. To maintain the stability of the milk production, organic farms had to increase the reliance on external fodder resources. The lack of security forage stores can explain the sensitivity of these farms and their incapacity to recover a good level of self-sufficiency

Description of the unsteady flow pattern from peak efficiency to near surge in subsonic centrifugal compressor stage

This paper aims to describe the flow structure modifications when the operating point moves from peak efficiency to near stall condition in a moderate pressure ratio centrifugal compressor stage consisted of a splittered unshrouded impeller and a vaned diffuser. The investigations are based on three-dimensional U-RANS simulation results. The flow is described in the impeller and in the vaned diffuser through time-averaged flow quantities and unsteady fluctuations. Results show that at low mass flow rate, the effects of secondary flow in the impeller are more pronounced, inducing both, high time-averaged values and temporal fluctuations of the flow angle near the shroud at the diffuser inlet, leading to vane suction side boundary layer separation. Pressure waves due to impeller diffuser interaction spread through the vaned diffuser generating unsteadiness which intensifies at near surge condition

Data on face-to-face contacts in an office building suggests a low-cost vaccination strategy based on community linkers

Empirical data on contacts between individuals in social contexts play an important role in providing information for models describing human behavior and how epidemics spread in populations. Here, we analyze data on face-to-face contacts collected in an office building. The statistical properties of contacts are similar to other social situations, but important differences are observed in the contact network structure. In particular, the contact network is strongly shaped by the organization of the offices in departments, which has consequences in the design of accurate agent-based models of epidemic spread. We consider the contact network as a potential substrate for infectious disease spread and show that its sparsity tends to prevent outbreaks of rapidly spreading epidemics. Moreover, we define three typical behaviors according to the fraction $f$ of links each individual shares outside its own department: residents, wanderers and linkers. Linkers ($f\sim 50\%$) act as bridges in the network and have large betweenness centralities. Thus, a vaccination strategy targeting linkers efficiently prevents large outbreaks. As such a behavior may be spotted a priori in the offices' organization or from surveys, without the full knowledge of the time-resolved contact network, this result may help the design of efficient, low-cost vaccination or social-distancing strategies

Experimental investigation of practical unforgeable quantum money

Wiesner's unforgeable quantum money scheme is widely celebrated as the first quantum information application. Based on the no-cloning property of quantum mechanics, this scheme allows for the creation of credit cards used in authenticated transactions offering security guarantees impossible to achieve by classical means. However, despite its central role in quantum cryptography, its experimental implementation has remained elusive because of the lack of quantum memories and of practical verification techniques. Here, we experimentally implement a quantum money protocol relying on classical verification that rigorously satisfies the security condition for unforgeability. Our system exploits polarization encoding of weak coherent states of light and operates under conditions that ensure compatibility with state-of-the-art quantum memories. We derive working regimes for our system using a security analysis taking into account all practical imperfections. Our results constitute a major step towards a real-world realization of this milestone protocol.Comment: 10 pages, 5 figure

Valérie Toureille, Crime et châtiment au Moyen Âge (ve-xve siècle)

V. Toureille, Maître de conférences en histoire du Moyen Âge à l’Université de Cergy-Pontoise, propose dans cet ouvrage une belle synthèse sur le sujet impliqué par son titre. Ce dernier se présente sous la forme de quatre chapitres thématiques : le premier est consacré à la société médiévale et au crime, le second, tout en traitant des figures du crime, s’interroge sur la faisabilité de dresser « l’ébauche d’une sociologie criminelle », le troisième s’intéresse au criminel devant ses juges e..

Eshu’s tricks: Fragments for a communicational analysis of voting

Voting is a sort of black hole in work on political communication in information and communication sciences. As for electoral studies in political science, they provide increasingly precise information about who electors are and the circumstances under which they decide how to vote, but they struggle to enlighten what voters mean by their votes. This paper outlines a fresh approach to voting as a communicational process. In a context of crisis of representation, recent work in ICS encourages the use of “incommunication” to analyse the relationship that forms during political elections between governors and governed. A diversion by way of political anthropology will lead to mention of Eshu (Elegba, Legba), who in Africa forms a synthesis between communication that is inherent in all forms of power and the individual and collective expression of the guardians of power