The Amplitude of Non-Equilibrium Quantum Interference in Metallic Mesoscopic Systems

We study the influence of a DC bias voltage V on quantum interference corrections to the measured differential conductance in metallic mesoscopic wires and rings. The amplitude of both universal conductance fluctuations (UCF) and Aharonov-Bohm effect (ABE) is enhanced several times for voltages larger than the Thouless energy. The enhancement persists even in the presence of inelastic electron-electron scattering up to V ~ 1 mV. For larger voltages electron-phonon collisions lead to the amplitude decaying as a power law for the UCF and exponentially for the ABE. We obtain good agreement of the experimental data with a model which takes into account the decrease of the electron phase-coherence length due to electron-electron and electron-phonon scattering.Comment: New title, refined analysis. 7 pages, 3 figures, to be published in Europhysics Letter

Detection of very-high-energy gamma-ray emission from the vicinity of PSR B1706-44 with H.E.S.S

The energetic pulsar PSR B1706-44 and the adjacent supernova remnant (SNR) candidate G 343.1-2.3 were observed by H.E.S.S. during a dedicated observational campaign in 2007. A new source of very-high-energy (VHE; E > 100 GeV) gamma-ray emission, HESS J1708-443, was discovered with its centroid at RA(J2000) = 17h08m10s and Dec(J2000) = -44d21', with a statistical error of 3 arcmin on each axis. The VHE gamma-ray source is significantly more extended than the H.E.S.S. point-spread function, with an intrinsic Gaussian width of 0.29 +/- 0.04 deg. Its energy spectrum can be described by a power law with a photon index Gamma = 2.0 +/- 0.1 (stat) +/- 0.2 (sys). The integral flux measured between 1-10 TeV is ~17% of the Crab Nebula flux in the same energy range. The possible associations with PSR B1706-44 and SNR G343.1-2.3 are discussed.Comment: 4+ pages, 2 figures; v1 submitted to ICRC Proceedings on 15 May 2009; v2 has additional references and minor change

SPI Measurements of the Diffuse Galactic Hard X-ray Continuum

INTEGRAL Spectrometer SPI data from the first year of the Galactic Centre Deep Exposure has been analysed for the diffuse continuum from the Galactic ridge. A new catalogue of sources from the INTEGRAL Imager IBIS has been used to account for their contribution to the celestial signal. Apparently diffuse emission is detected at a level ~10% of the total source flux. A comparison of the spectrum of diffuse emission with that from an analysis of IBIS data alone shows that they are consistent. The question of the contribution of unresolved sources to this ridge emission is still open.Comment: Proceedings of the 5th INTEGRAL Workshop, Munich 16-20 February 2004. ESA SP-552. Reference to Terrier et al. (2004) updated to include astro-ph versio

Improvement of walking speed prediction by accelerometry and altimetry, validated by satellite positioning

Activity monitors based on accelerometry are used to predict the speed and energy cost of walking at 0% slope, but not at other inclinations. Parallel measurements of body accelerations and altitude variation were studied to determine whether walking speed prediction could be improved. Fourteen subjects walked twice along a 1.3km circuit with substantial slope variations (−17% to +17%). The parameters recorded were body acceleration using a uni-axial accelerometer, altitude variation using differential barometry, and walking speed using satellite positioning (DGPS). Linear regressions were calculated between acceleration and walking speed, and between acceleration/altitude and walking speed. These predictive models, calculated using the data from the first circuit run, were used to predict speed during the second circuit. Finally the predicted velocity was compared with the measured one. The result was that acceleration alone failed to predict speed (meanr=0.4). Adding altitude variation improved the prediction (meanr=0.7). With regard to the altitude/acceleration-speed relationship, substantial inter-individual variation was found. It is concluded that accelerometry, combined with altitude measurement, can assess position variations of humans provided inter-individual variation is taken into account. It is also confirmed that DGPS can be used for outdoor walking speed measurements, opening up new perspectives in the field of biomechanic

Place de la néotectonique dans l'évaluation de l'aléa sismique : exemple de la Provence ( France)

Mémoire HS n° 15 - Géologie Alpine Risques naturels dans le Sud-est de la France - Colloque Association des Géologues du Sud-est - Avignon, 19 et 20 octobre 1989La néotectonique participe de façon déterminante à toute étude d'évaluation de l'aléa sismique. A cette fin, la Provence occidentale (France) a récemment fait l'objet d'un nouveau bilan néotectonique. Celui-ci s'est appuyé, d'une part sur l'examen critique de données extraites d'une compilation bibliographique et d'autre part sur des éléments nouveaux résultant d'observations de terrain ou d'investigations particulières telles que la comparaison des nivellements et l'analyse morphostructurale. Les résultats obtenus ont permis de prouver l'activité tectonique quaternaire de certaines failles et de révéler plusieurs traits néotectoniques nouveaux. Ces résultats, qui ont constitué des éléments primordiaux lors de l'élaboration du schéma sismotectonique global de la Provence occidentale ont été intégré dans deux types d'études d'aléa sismique: d'une part lors de la réalisation des Plans d'Expositions aux Risques Sismiques et d'autre part, lors des études des dangers concernant les installations industrielles à haut risque des Bouches-du-Rhône. En outre, d'un point de vue fondamental , la relation néotectonique-aléa sismique confrontée à des problèmes pratiques posés par l'ingénieur, a permis de faire avancer notablement la réflexion sur la notion de faille active en domaine intraplaque de sismicité faible à modérée

Subclinical giant cell arteritis in polymyalgia rheumatica: Concurrent conditions or a common spectrum of inflammatory diseases?

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common conditions in older adults. Their clinical connection has been recognized over time, with many patients experiencing both conditions separately, simultaneously or in temporal sequence to each other. Early GCA detection is essential to prevent vascular damage, but identifying subclinical GCA in PMR patients remains a challenge and routine screening is not standard practice. Subclinical GCA prevalence in newly diagnosed PMR patients ranges from 23 to 29%, depending on the screening method. Vessel wall imaging and temporal artery biopsy can detect subclinical GCA. Epidemiology and trigger factors show similarities between the two conditions, but PMR is more common than GCA. Genetic and pathogenesis studies reveal shared inflammatory mechanisms involving dendritic cells, pro-inflammatory macrophages, and an IL-6 signature. However, the inflammatory infiltrates differ, with extensive T cell infiltrates seen in GCA while PMR shows an incomplete profile of T cell and macrophage-derived cytokines. Glucocorticoid treatment is effective for both conditions, but the steroid requirements vary. PMR overall mortality might be similar to the general population, while GCA patients with aortic inflammatory aneurysms face increased mortality risk. The GCA-PMR association warrants further research. Considering their kinship, recently the term GCA-PMR Spectrum Disease (GPSD) has been proposed

Constraining leptonic emission scenarios for the PeVatron candidate HESS J1702-420 with deep XMM-Newton observations

The unidentified TeV source HESS J1702-420 has recently been proposed as a new hadronic PeVatron candidate, based on the discovery of a small-scale emission sub-region with extremely hard gamma-ray spectrum up to 100 TeV (named HESS J1702-420A). Given the difficulty to discriminate between a hadronic or leptonic origin of the TeV emission, based on the H.E.S.S. measurement alone, we opted for a multi-wavelength approach. A deep X-ray observation was carried out using the XMM-Newton satellite, with the goal of probing a possible association with a hidden leptonic accelerator. No evidence of a clear counterpart for HESS J1702-420A was found in the X-ray data. After excluding an association with all nearby X-ray point sources, we derived strict upper limits on the diffuse X-ray emission and average magnetic field in the HESS J1702-420A region. We additionally report the serendipitous discovery of a new extended X-ray source, whose association with HESS J1702-420A is not obvious but cannot be ruled out either. A set of scripts dedicated to the multi-wavelength modeling of X-ray and gamma-ray data, based on Gammapy, Naima and Xspec, was developed in the context of this work and is made publicly available along with this paper.Comment: Accepted for publication in Astronomy & Astrophysics, 13 pages, 11 figures, 3 table

Treatment of gastrointestinal hemorrhage

Background: We assessed the value of selective arteriography in the diagnosis and management of acute gastrointestinal hemorrhage. Methods: We reviewed the records of 107 consecutive patients who had gastrointestinal hemorrhage and underwent selective arteriography between January 1992 and October 2003: 10 had upper gastrointestinal bleeding, 79 had lower gastrointestinal bleeding, and 18 had varicose bleeding with portal hypertension. Selective embolization was attempted in 15 patients to obtain hemostasis. Angiographic findings were reviewed and prospective reports were compared with the final diagnosis and outcome. Results: Of 129 angiographic studies, 36 correctly revealed the bleeding site and 93 were negative. Extravasation was seen in 24 cases at the level of stomach (n = 2), duodenum (n = 1), small bowel (n = 5), or colon (n = 16). Indirect signs of bleeding sources were identified in 12 patients (stomach in one, small bowel in four, large bowel in four, liver in three). Transcatheter embolization induced definitive hemostasis in 11 of 15 patients (73%), namely in the stomach (n = 2), small bowel (n = 3), colon (n = 7), and liver (n = 3). Three patients required surgery after embolization. Conclusion: Abdominal arteriography may localize gastrointestinal bleeding sources in approximately one-third of cases. Selective embolization may provide definitive hemostasis in most instance

Evaluation of therapists’ individual characteristics’ influence on recommendations to CLBP patients

IntroductionThis study measured different therapists’ biopsychosocial parameters and their influence on treatment recommendations for chronic low back pain (CLBP) patients. Based on previous studies and with a biopsychosocial approach, this work aimed to understand the variations in recommendations depending on personal dispositions.MethodsEighty-two therapists (aged 37±11 years, 34 men/48 women) were recruited within our rehabilitation clinic (CRR). Their physical activity was objectively assessed by tri-axial accelerometry and questionnaires have been used to evaluate the following variables: subjective physical activity (BAECKE), pain attitudes and beliefs (TSK and POAM-P), anxiety and depression (HADS), uncertainty intolerance (EII) and social desirability (MC-SDS). Objective stress level was measured by salivary cortisol.In order to measure the variability in recommendations, 3 validated vignettes for CLBP patients management were distributed.ResultsBehavioural patterns coping with pain (Avoidance, Overdoing and Pacing) do occur in therapists (10% Avoidance, 47% Pacing and 43% Overdoing) and do affect recommendations’ application. These 3 different patterns are also related to age, sex, BMI, depression and physical activity. Others relations are currently being analysed.ConclusionThis study suggests that we could categorise therapists depending onidiosyncratics variablespersonal dispositions. This classification would determine recommendations orientation for physical and professional activity. For future research studies, it would be interesting to deal in depth with these relations in order to individualize recommendations to get a better rehabilitation procedure

Systematic effects induced on IBIS detectors by background and inhomogeneity of the spatial response

The spatial distribution of the background events may affect the source detection capability of IBIS at high energies (> 200 keV) for both ISGRI and PICsIT layers. The observed background is found to be variable and spatially structured, and in some cases its properties strongly deviate from the expected statistical behaviour. Background correction methods are then necessary to improve the quality of the shadowgrams obtained from sources. In order to perform an efficient flat-fielding the response of the detector to both source gamma-rays and background events is investigated using data from Monte Carlo simulations and in-flight calibration observations.Comment: 5 pages, 1 latex file, 6 figures, accepted for publication on Astronomy and Astrophysics, INTEGRAL special issu