Evanescent straight tapered-fiber coupling of ultra-high Q optomechanical micro-resonators in a low-vibration helium-4 exchange-gas cryostat

We developed an apparatus to couple a 50-micrometer diameter whispering-gallery silica microtoroidal resonator in a helium-4 cryostat using a straight optical tapered-fiber at 1550nm wavelength. On a top-loading probe specifically adapted for increased mechanical stability, we use a specifically-developed "cryotaper" to optically probe the cavity, allowing thus to record the calibrated mechanical spectrum of the optomechanical system at low temperatures. We then demonstrate excellent thermalization of a 63-MHz mechanical mode of a toroidal resonator down to the cryostat's base temperature of 1.65K, thereby proving the viability of the cryogenic refrigeration via heat conduction through static low-pressure exchange gas. In the context of optomechanics, we therefore provide a versatile and powerful tool with state-of-the-art performances in optical coupling efficiency, mechanical stability and cryogenic cooling.Comment: 8 pages, 6 figure

Results of a self-triggered prototype system for radio-detection of extensive air showers at the Pierre Auger Observatory

We describe the experimental setup and the results of RAuger, a small radio-antenna array, consisting of three fully autonomous and self-triggered radio-detection stations, installed close to the center of the Surface Detector (SD) of the Pierre Auger Observatory in Argentina. The setup has been designed for the detection of the electric field strength of air showers initiated by ultra-high energy cosmic rays, without using an auxiliary trigger from another detection system. Installed in December 2006, RAuger was terminated in May 2010 after 65 registered coincidences with the SD. The sky map in local angular coordinates (i.e., zenith and azimuth angles) of these events reveals a strong azimuthal asymmetry which is in agreement with a mechanism dominated by a geomagnetic emission process. The correlation between the electric field and the energy of the primary cosmic ray is presented for the first time, in an energy range covering two orders of magnitude between 0.1 EeV and 10 EeV. It is demonstrated that this setup is relatively more sensitive to inclined showers, with respect to the SD. In addition to these results, which underline the potential of the radio-detection technique, important information about the general behavior of self-triggering radio-detection systems has been obtained. In particular, we will discuss radio self-triggering under varying local electric-field conditions.Comment: accepted for publication in JINS

\epsilon-regularity for systems involving non-local, antisymmetric operators

We prove an epsilon-regularity theorem for critical and super-critical systems with a non-local antisymmetric operator on the right-hand side. These systems contain as special cases, Euler-Lagrange equations of conformally invariant variational functionals as Rivi\`ere treated them, and also Euler-Lagrange equations of fractional harmonic maps introduced by Da Lio-Rivi\`ere. In particular, the arguments presented here give new and uniform proofs of the regularity results by Rivi\`ere, Rivi\`ere-Struwe, Da-Lio-Rivi\`ere, and also the integrability results by Sharp-Topping and Sharp, not discriminating between the classical local, and the non-local situations

Boundary regularity via Uhlenbeck-Rivi\`ere decomposition

We prove that weak solutions of systems with skew-symmetric structure, which possess a continuous boundary trace, have to be continuous up to the boundary. This applies, e.g., to the H-surface system with bounded H and thus extends an earlier result by P. Strzelecki and proves the natural counterpart of a conjecture by E. Heinz. Methodically, we use estimates below natural exponents of integrability and a recent decomposition result by T.Rivi\`ere.Comment: 20 page

Management and orientation of geriatric patients admitted to emergencies for a fall: results of the French prospective OREGoN cohort study

Falls in older adults are a frequent reason for admission to the emergency department, associated with greater morbidity and mortality risks, and justify specialized geriatric expertise. Our objective was to determine i) the number of older fallers admitted to the emergency department for a serious fall, and ii) the proportion of those who were referred to a geriatrician in the following 12 months. METHODS: We included all patients aged 75 and over admitted to the emergency department of the University hospital of Angers, France, for a fall between 1st October and 1st November 2015. The consensual criteria proposed by the French national authority for health (2009) were used to define serious falls. RESULTS: Of the 214 older fallers admitted to the emergency department, 213 (99.5%) had at least one severity criterion for the fall. Only 40 older patients (18.7%) were referred to a geriatrician during the following 12 months. They exhibited more frequently a post-fall syndrome (p=0.007), more than 3 fall risk factors (p <0.001), and took more often an anticoagulant (p=0.032) than those who had not been referred to a geriatrician. CONCLUSIONS: Although almost all older fallers admitted to the emergency room had experienced a serious fall, only a minority of them received a geriatric assessment in the following year

Cryogenic properties of optomechanical silica microcavities

We present the optical and mechanical properties of high-Q fused silica microtoroidal resonators at cryogenic temperatures (down to 1.6 K). A thermally induced optical multistability is observed and theoretically described; it serves to characterize quantitatively the static heating induced by light absorption. Moreover the influence of structural defect states in glass on the toroid mechanical properties is observed and the resulting implications of cavity optomechanical systems on the study of mechanical dissipation discussed.Comment: 4 pages, 3 figure

3DC2 : a multiple view interactive platform

International audienceCet article présente un prototype de 3DC21, un système interactif multi-opérateur multi-vues. Ce système a pour principale caractéristique la possibilité de présenter deux vues 3D stéréoscopiques distinctes à deux opérateurs travaillant sur la même surface interactive. Il a pour cible applicative des contextes de travail coopératif pour lesquels la 3D est primordiale. Il est démontré sur un scénario de surveillance urbaine à base de drones aéroportés

Atomic environment and interfacial structural order of TiAlN/Mo multilayers

Multilayered TiAlN/Mo coatings were deposited by dc reactive magnetron sputtering in a custom-made chamber. In order to assess the composition of these coatings, a combined study of Extended X-ray Absorption Fine Structure (EXAFS) and Rutherford Backscattering Spectrometry (RBS) experiments were performed. Through the simulation of the EXAFS spectra, giving the local environment of the titanium atoms inside the nitride (TiAlN), a cubic phase has been evidenced with aluminium atoms occupying titanium sites. For modulation periods in the range of 3.6–11.8 nm, RBS simulations on these multilayers also enabled the determination of the level of intermixing that occurs at the interfaces as a function of the negative bias voltage and number of layers. It was observed that the intermixing width could be as high as 2.1 nm for the roughest samples (larger periods) or as low as 0.4 nm for those with the sharpest interfaces (smaller periods).Comunidade Europeia (CE). Fundo Europeu de Desenvolvimento Regional (FEDER) -Ministério da Ciência e Tecnologia.Cooperação Científica e Tecnológica Internacional (ICCTI) - Ambassade de France in Portugal - Project no. 543 B3/2001.Fundação para a Ciência e a Tecnologia (FCT) - Programa Operacional “Ciência, Tecnologia, Inovação - POCTI/32670/CTM/2000

Standby and off-mode Power Demand of new Appliances in the Market

Proccedings are online at http://re.jrc.ec.europa.eu/energyefficiency/EEDAL/EEDAL11_Proceedings/19/138_Almeida_Anibal_ConsumerElectronics&ICT2.pdfPresentation available at http://www.eedal.dk/Conference/~/media/EEDAL/Sessions/Session%205/SELINA-EEDAL2011_Copenhagen_Gigli.ashxInternational audienceFor more than a decade, it has been recognized that the energy consumption in low power modes for electrical and electronic products is an important issue because it represent permanent loads (sometimes up to 24 hours per day) of a huge number of products. With the 1 W standby initiative of the International Energy Agency (IEA), several low power mode measurement campaigns have been led on a regular basis in a number of countries outside and inside Europe Union (EU). Based on these results and on the Energy-using Products Study Lot 6, the EU has prepared new regulation to limit the standby and off-mode power consumption of non-networked household electronic and electrical equipment, which is being applied since January 2010. The IEE project SELINA carried out a large scale monitoring campaign in shops in order to characterize the low power modes of new appliances being sold in the EU market. In order to ensure consistency of the collected data, a common measurement methodology was developed and the same high resolution measurement equipment was used by all partners. This publication analyzes the results of more than 6000 different equipments measured in the 12 EU countries involved in the project. Standby and off-mode values by product categories are analyzed and compared with data from other regions of the World. The measurements are also benchmarked against the new 2010/2013 EU standby and off mode regulation thresholds and the impact of the EU regulation is discussed. In parallel with the measurement campaign, an awareness study of the retailers was carried out. This survey helps to understand the customers' buying motivations and the influence of retailers' advice in their choices. An overview of the collected policies and initiatives to improve the low power mode energy consumption are reviewed

A novel lipase with dual localisation in Trypanosoma brucei

Experiment costs were supported by Université de Bordeaux (https://www.u-bordeaux.fr), CNRS (https://www.cnrs.fr) and the Agence Nationale de la Recherche through the grants GLYCONOV (grant number ANR-15-CE-15-0025-01) and ADIPOTRYP (grant number ANR19-CE15-0004-01). This work was also funded by the Laboratoire d’Excellence (LabEx) “French Parasitology Alliance For Health Care” (ANR-11-LABX-0024-PARAFRAP, https://labex-parafrap.fr). This work was also partially supported by the European Research Council (FatTryp, ref. 771714) and by Fundacao para a Ciencia e Tecnologia (CEECIND/03322/2018) awarded to LMF.Phospholipases are esterases involved in lipid catabolism. In pathogenic micro-organisms (bacteria, fungi, parasites) they often play a critical role in virulence and pathogenicity. A few phospholipases (PL) have been characterised so far at the gene and protein level in unicellular parasites including African trypanosomes (AT). They could play a role in different processes such as host–pathogen interaction, antigenic variation, intermediary metabolism. By mining the genome database of AT we found putative new phospholipase candidate genes and here we provided biochemical evidence that one of these has lipolytic activity. This protein has a unique non-canonical glycosome targeting signal responsible for its dual localisation in the cytosol and the peroxisomes-related organelles named glycosomes. We also show that this new phospholipase is excreted by these pathogens and that antibodies directed against this protein are generated during an experimental infection with T. brucei gambiense, a subspecies responsible for infection in humans. This feature makes this protein a possible tool for diagnosis.Publisher PDFPeer reviewe