82 research outputs found
Antibunched photons emitted by a dc-biased Josephson junction
We show experimentally that a dc biased Josephson junction in series with a high-enough-impedance microwave resonator emits antibunched photons. Our resonator is made of a simple microfabricated spiral coil that resonates at 4.4 GHz and reaches a 1.97kΩ characteristic impedance. The second order correlation function of the power leaking out of the resonator drops down to 0.3 at zero delay, which demonstrates the antibunching of the photons emitted by the circuit at a rate of 6Ă10^7 photons per second. Results are found in quantitative agreement with our theoretical predictions. This simple scheme could offer an efficient and bright single-photon source in the microwave domain
Acting Intuition into Sense: How Film Crews Make Sense with Embodied Ways of Knowing
This study contributes to a holistic understanding of sensemaking by going beyond the mindâbody dualism. To do so, we focus analytically on a phenomenon that operates at the nexus of mind and body: intuition. By observing four film crews, we unpack how people act their intuition into sense â that is, how they transform, through action, an initial sense (intuition) that is tacit, intimate, and complex into one that is publicly displayed, simpler, and ordered (i.e., a developed sense). Our model identifies two sensemaking trajectories, each of which involves several bodily actions (e.g., displaying feelings, working hands-on, speaking assertively). These actions enable intuition to express a facet of itself and acquire new properties. This study makes three important contributions. First, it develops the holistic-relational character of sensemaking by locating it in the relations among multiple loci (cognition, language, body, and materiality) rather than in each one disjunctively. Second, it theorizes embodied sensemaking as a transformative process entailing a rich repertoire of bodily actions. Third, it extends sensemaking research by attending to the physicality and materiality of language in embodied sensemaking
Generating Two Continuous Entangled Microwave Beams Using a dc-Biased Josephson Junction
We show experimentally that a dc-biased Josephson junction in series with two microwave resonators emits entangled beams of microwaves leaking out of the resonators. In the absence of a stationary phase reference for characterizing the entanglement of the outgoing beams, we measure second-order coherence functions to prove the entanglement. The experimental results are found in quantitative agreement with theory, proving that the low-frequency noise of the dc bias is the main limitation for the coherence time of the entangled beams. This agreement allows us to evaluate the entropy of entanglement of the resonators, estimate the entanglement flux at their output, and to identify the improvements that could bring this device closer to a useful bright source of entangled microwaves for quantum-technological applications
Caractérisation des processus hydrologiques sur le super-site de la Donga : haut bassin de l'Ouémé (Bénin), ORE AMMA-CATCH
Intuition: Myth or a Decision-making Tool?
Faced with todayâs ill-structured business environment of fast-paced change and rising uncertainty, organizations have been searching for management tools that will perform satisfactorily under such ambiguous conditions. In the arena of managerial decision making, one of the approaches being assessed is the use of intuition. Based on our definition of intuition as a non-sequential information-processing mode, which comprises both cognitive and affective elements and results in direct knowing without any use of conscious reasoning, we develop a testable model of integrated analytical and intuitive decision making and propose ways to measure the use of intuition
Mechanistic Insights on the Inhibition of C5 DNA Methyltransferases by Zebularine
In mammals DNA methylation occurs at position 5 of cytosine in a CpG context and regulates gene expression. It plays an important role in diseases and inhibitors of DNA methyltransferases (DNMTs)âthe enzymes responsible for DNA methylationâare used in clinics for cancer therapy. The most potent inhibitors are 5-azacytidine and 5-azadeoxycytidine. Zebularine (1-(ÎČ-D-ribofuranosyl)-2(1H)- pyrimidinone) is another cytidine analog described as a potent inhibitor that acts by forming a covalent complex with DNMT when incorporated into DNA. Here we bring additional experiments to explain its mechanism of action. First, we observe an increase in the DNA binding when zebularine is incorporated into the DNA, compared to deoxycytidine and 5-fluorodeoxycytidine, together with a strong decrease in the dissociation rate. Second, we show by denaturing gel analysis that the intermediate covalent complex between the enzyme and the DNA is reversible, differing thus from 5-fluorodeoxycytidine. Third, no methylation reaction occurs when zebularine is present in the DNA. We confirm that zebularine exerts its demethylation activity by stabilizing the binding of DNMTs to DNA, hindering the methylation and decreasing the dissociation, thereby trapping the enzyme and preventing turnover even at other sites
Effect of Rainfall Regime and Slope on Runoff in a Gullied Loess Region on the Loess Plateau in China
Agroforesterie et services écosystémiques en zone tropicale
Respectueux de lâenvironnement et garantissant une sĂ©curitĂ© alimentaire soutenue par la diversification des productions et des revenus quâils procurent, les systĂšmes agroforestiers apparaissent comme un modĂšle prometteur dâagriculture durable dans les pays du Sud les plus vulnĂ©rables aux changements globaux. Cependant, ces systĂšmes agroforestiers ne peuvent ĂȘtre optimisĂ©s quâĂ condition de mieux comprendre et de mieux maĂźtriser les facteurs de leurs productions. Lâouvrage prĂ©sente un ensemble de connaissances rĂ©centes sur les mĂ©canismes biophysiques et socio-Ă©conomiques qui sous-tendent le fonctionnement et la dynamique des systĂšmes agroforestiers. Il concerne, dâune part les systĂšmes agroforestiers Ă base de cultures pĂ©rennes, telles que cacaoyers et cafĂ©iers, de rĂ©gions tropicales humides en AmĂ©rique du Sud, en Afrique de lâEst et du Centre, dâautre part les parcs arborĂ©s et arbustifs Ă base de cultures vivriĂšres, principalement de cĂ©rĂ©ales, de la rĂ©gion semi-aride subsaharienne dâAfrique de lâOuest. Il synthĂ©tise les derniĂšres avancĂ©es acquises grĂące Ă plusieurs projets associant le Cirad, lâIRD et leurs partenaires du Sud qui ont Ă©tĂ© conduits entre 2012 et 2016 dans ces rĂ©gions. Lâensemble de ces projets sâarticulent autour des dynamiques des systĂšmes agroforestiers et des compromis entre les services de production et les autres services socio-Ă©cosystĂ©miques que ces systĂšmes fournissent
Evaluating LSM-based water budgets over a West African basin assisted with a river routing scheme
Within the framework of the African Monsoon Multidisciplinary Analysis (AMMA) Land Surface Model Intercomparison Project phase 2 (ALMIP-2), this study evaluates the water balance simulated by the Interactions between Soil, Biosphere, and Atmosphere (ISBA) over the upper Oueme River basin, in Benin, using a mesoscale river routing scheme (RRS). The RRS is based on the nonlinear Muskingum-Cunge method coupled with two linear reservoirs that simulate the time delay of both surface runoff and base flow that are produced by land surface models. On the basis of the evidence of a deep water-table recharge in that region, a reservoir representing the deep-water infiltration (DWI) is introduced. The hydrological processes of the basin are simulated for the 2005-08 AMMA field campaign period during which rainfall and streamflow data were intensively collected over the study area. Optimal RRS parameter sets were determined for three optimization experiments that were performed using daily streamflow at five gauges within the basin. Results demonstrate that the RRS simulates streamflow at all gauges with relative errors varying from -20% to 3% and Nash-Sutcliffe coefficients varying from 0.62 to 0.90. DWI varies from 24% to 67% of the base flow as a function of the subbasin. The relatively simple reservoir DWI approach is quite robust, and further improvements would likely necessitate more complex solutions (e.g., considering seasonality and soil type in ISBA); thus, such modifications are recommended for future studies. Although the evaluation shows that the simulated streamflows are generally satisfactory, further field investigations are necessary to confirm some of the model assumptions
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