L'assurance contre les tremblements de terre

L'assuranee des batiments et du mobilier contre les tremblements de terre n'a, jusqu'à présent, pas connu le développement auquel on pouvait s'attendre en considérant les dégâts souvent énormes causés par ces phénomènes. Elle est pratiquée presque exclusivement dans les régions particulièrement dangereuses comme la Californie, le Japon et quelques autres pays, et même dans ces territoires les valeurs assurées sont peu importantes comparées a celles de l'assurance contre l'incendie par exempl

Measurements of a Quantum Dot with an Impedance-Matching On-Chip LC Resonator at GHz Frequencies

We report the realization of a bonded-bridge on-chip superconducting coil and its use in impedance-matching a highly ohmic quantum dot (QD) to a $\rm{3~GHz}$ measurement setup. The coil, modeled as a lumped-element $LC$ resonator, is more compact and has a wider bandwidth than resonators based on coplanar transmission lines (e.g. $\lambda/4$ impedance transformers and stub tuners) at potentially better signal-to-noise ratios. In particular for measurements of radiation emitted by the device, such as shot noise, the 50$\times$ larger bandwidth reduces the time to acquire the spectral density. The resonance frequency, close to 3.25 GHz, is three times higher than that of the one previously reported wire-bonded coil. As a proof of principle, we fabricated an $LC$ circuit that achieves impedance-matching to a $\rm{\sim 15~k\Omega}$ load and validate it with a load defined by a carbon nanotube QD of which we measure the shot noise in the Coulomb blockade regime.Comment: 7 pages, 6 figure

Wind estimates from cloud motions: Preliminary results from phases 1, 2, and 3 of an in situ aircraft verification experiment

Low level aircraft equipped with Inertial Navigation Systems (INS) were used to define the vertical extent and horizontal motion of a cloud and to measure the ambient wind field. A high level aircraft, also equipped with an INS, took photographs to describe the horizontal extent of the cloud field and to measure cloud motion. The aerial photographs were also used to make a positive identification in a satellite picture of the cloud observed by the low level aircraft. The experiment was conducted over the tropical oceans in the vicinity of Florida, Puerto Rico, Panama and in the Western Gulf of Mexico. Results for tropical cumulus clouds indicate excellent agreement between the cloud motion and the wind at the cloud base. The magnitude of the vector difference between the cloud motion and the cloud base wind is less than 1.3 m/sec for 67% of the cases with track lengths of 1 hour or longer. The cirrus cloud motions agreed best with the mean wind in the cloud layer with a vector difference of about 1.6 m/sec

Absolutely continuous spectrum for a random potential on a tree with strong transverse correlations and large weighted loops

We consider random Schr\"odinger operators on tree graphs and prove absolutely continuous spectrum at small disorder for two models. The first model is the usual binary tree with certain strongly correlated random potentials. These potentials are of interest since for complete correlation they exhibit localization at all disorders. In the second model we change the tree graph by adding all possible edges to the graph inside each sphere, with weights proportional to the number of points in the sphere.Comment: 25 pages, 4 figure

Shot noise of a quantum dot measured with GHz stub impedance matching

The demand for a fast high-frequency read-out of high impedance devices, such as quantum dots, necessitates impedance matching. Here we use a resonant impedance matching circuit (a stub tuner) realized by on-chip superconducting transmission lines to measure the electronic shot noise of a carbon nanotube quantum dot at a frequency close to 3 GHz in an efficient way. As compared to wide-band detection without impedance matching, the signal to noise ratio can be enhanced by as much as a factor of 800 for a device with an impedance of 100 k$\Omega$. The advantage of the stub resonator concept is the ease with which the response of the circuit can be predicted, designed and fabricated. We further demonstrate that all relevant matching circuit parameters can reliably be deduced from power reflectance measurements and then used to predict the power transmission function from the device through the circuit. The shot noise of the carbon nanotube quantum dot in the Coulomb blockade regime shows an oscillating suppression below the Schottky value of $2eI$, as well an enhancement in specific regions.Comment: 6 pages, 4 figures, supplementar

Placebos in der Psychotherapieforschung – eine systematische Analyse am Beispiel der systematischen Desensibilisierung

Hintergrund: Die Voraussetzungen der randomisierten, Placebo-kontrollierten Evaluation - die Ununterscheidbarkeit der Therapiebedingungen für die Patienten und die Verblindung der Therapeuten - sind in der Psychotherapieforschung nicht uneingeschränkt gegeben. Das Ziel dieser qualitativen systematischen Übersichtsarbeit ist es, am Beispiel der systematischen Desensibilisierung (SD) die Vorgehensweisen zur Bestimmung der Behandlungsspezifität zu beschreiben und deren theoretische und praktische Implikationen zu diskutieren. Methodik: Auf der Basis einer systematischen Literaturrecherche in PsycINFO und PubMed für den Zeitraum von 1976-2015 wurden Psychotherapiestudien gesucht, in denen Patienten mit Angstsymptomen einer SD- oder Placebo-Gruppe zugewiesen und verglichen wurden. Nach Extraktion der gewählten Moderator-Variablen konnten 11 Studien eingeschlossen werden. Ergebnisse: Die Ergebnisse zu den spezifischen Effekten der SD waren nicht einheitlich. Eine durchgeführte Moderator-Analyse zeigte, dass der Nachweis spezifischer Effekte von der Glaubwürdigkeit des Placebos und dem dabei erlebten Ausmaß emotionaler Erfahrungen abhängig ist. Schlussfolgerung: Ob ein bestimmtes psychotherapeutisches Verfahren als spezifisch einzustufen ist, hängt von der Operationalisierung der Placebo-Kontrolle ab. Insbesondere bei SD scheint die Einschränkung des zu bearbeitenden Themas und in der Folge die Unterbindung der emotionalen Erfahrung des Patienten innerhalb der Kontrollbedingung eine Voraussetzung dafür zu sein, spezifische Effekte der SD zu finden

Locating the Source of Diffusion in Large-Scale Networks

How can we localize the source of diffusion in a complex network? Due to the tremendous size of many real networks--such as the Internet or the human social graph--it is usually infeasible to observe the state of all nodes in a network. We show that it is fundamentally possible to estimate the location of the source from measurements collected by sparsely-placed observers. We present a strategy that is optimal for arbitrary trees, achieving maximum probability of correct localization. We describe efficient implementations with complexity O(N^{\alpha}), where \alpha=1 for arbitrary trees, and \alpha=3 for arbitrary graphs. In the context of several case studies, we determine how localization accuracy is affected by various system parameters, including the structure of the network, the density of observers, and the number of observed cascades.Comment: To appear in Physical Review Letters. Includes pre-print of main paper, and supplementary materia

Partielle Quadrizepssehnenruptur bei einem sechsjährigen Jungen

Zusammenfassung: Bei Kindern werden Ausrissfrakturen der Patella häufiger beobachtet als Rupturen der Quadrizepssehne. Bei verdächtigen Verletzungen der Quadrizepssehne ist differenzialdiagnostisch ein Vergleich zwischen beiden Patellae mit Hilfe von konventionellem Röntgen und Ultraschall sinnvoll. Eine Arthroskopie empfiehlt sich für die Diagnose von begleitenden intraartikulären Knieläsionen und ermöglicht die Kniegelenkspülung mit Evakuierung des Hämarthro

The effects of catecholamine depletion on the neural response to fearful faces in remitted depression

Recent evidence suggests that increased psychophysiological response to negatively valenced emotional stimuli found in major depressive disorder (MDD) may be associated with reduced catecholaminergic neurotransmission. Fourteen unmedicated, remitted subjects with MDD (RMDD) and 13 healthy control subjects underwent catecholamine depletion with oral α-methyl-para-tyrosine (AMPT) in a randomized, placebo-controlled, double-blind crossover trial. Subjects were exposed to fearful (FF) and neutral faces (NF) during a scan with [15O]H2O positron emission tomography to assess the brain-catecholamine interaction in brain regions previously associated with emotional face processing. Treatment with AMPT resulted in significantly increased, normalized cerebral blood flow (CBF) in the left inferior temporal gyrus (ITG) and significantly decreased CBF in the right cerebellum across conditions and groups. In RMDD, flow in the left posterior cingulate cortex (PCC) increased significantly in the FF compared to the NF condition after AMPT, but remained unchanged after placebo, whereas healthy controls showed a significant increase under placebo and a significant decrease under AMPT in this brain region. In the left dorsolateral prefrontal cortex (DLPFC), flow decreased significantly in the FF compared to the NF condition under AMPT, and increased significantly under placebo in RMDD, whereas healthy controls showed no significant differences. Differences between AMPT and placebo of within-session changes in worry-symptoms were positively correlated with the corresponding changes in CBF in the right subgenual prefrontal cortex in RMDD. In conclusion, this study provided evidence for a catecholamine-related modulation of the neural responses to FF expressions in the left PCC and the left DLPFC in subjects with RMDD that might constitute a persistent, trait-like abnormality in MDD