Circuit Electromechanics with a Non-Metallized Nanobeam

We have realized a nano-electromechanical hybrid system consisting of a silicon nitride beam dielectrically coupled to a superconducting microwave resonator. We characterize the sample by making use of the Duffing nonlinearity of the strongly driven beam. In particular, we calibrate the amplitude spectrum of the mechanical motion and determine the electromechanical vacuum coupling. A high quality factor of 480,000 at a resonance frequency of 14 MHz is achieved at 0.5 K. The experimentally determined electromechanical vacuum coupling of 11.5 mHz is quantitatively compared with finite element based model calculations.Comment: Typos and one reference have been correcte

Long-term observation of midlatitude quasi 2-day waves by a water vapor radiometer

A mesospheric water vapor data set obtained by the middle atmospheric water vapor radiometer (MIAWARA) close to Bern, Switzerland (46.88°&thinsp;N, 7.46°&thinsp;E) during October 2010 to September 2017 is investigated to study the long-term evolution and variability of quasi 2-day waves (Q2DWs). We present a climatological overview and an insight on the dynamical behavior of these waves with the occurring spectrum of periods as seen from a midlatitude observation site. Such a large and nearly continuous measurement data set as ours is rare and of high scientific value. The core results of our investigation indicate that the activity of the Q2DW manifests in burst-like events and is higher during winter months (November–February) than during summer months (May–August) for the altitude region of the mesosphere (up to 0.02&thinsp;hPa in winter and up to 0.05&thinsp;hPa in summer) accessible for the instrument. Single Q2DW events reach at most about 0.8&thinsp;ppm in the H2O amplitudes. Further, monthly mean Q2DW amplitude spectra are presented and reveal a high-frequency variability between different months. A large fraction of identified Q2DW events (20&thinsp;%) develop periods between 38 and 40&thinsp;h. Further, we show the temporal evolution of monthly mean Q2DW oscillations continuously for all months and separated for single months over 7 years. The analysis of autobicoherence spectra gives evidence that Q2DWs are sometimes phase coupled to diurnal oscillations to a high degree and to waves with a period close to 18&thinsp;h.</p

Schwere Lithiumintoxikationen bei normalen Serumspiegeln

Anliegen Unser Ziel ist es, Faktoren zu identifizieren, die das Risiko einer Lithiumintoxikation trotz normaler Serumspiegel erhöhen. Methode Wir beschreiben zwei eigene Fälle und bewerten diese im Kontext der Literatur. Ergebnisse Alter, Begleiterkrankungen und psychopharmakologische Komedikation erhöhen das Risiko einer Lithiumintoxikation bei normalen Serumspiegeln. Diskussion Bei älteren, multimorbiden Patienten sollte eine engmaschige klinische Kontrolle inklusive Spiegelbestimmung und EEG erfolgen, bei klinischen Anzeichen der Intoxikation sollte auch bei unauffälligen Spiegeln ein Absetzen erwogen werden

Practicing Critical Research: Applying a Feminist Textual Analysis to the Film 300

This single-class activity was developed to give students hands-on experience with critical research. The purpose of this activity is to assist students in developing critical, textual analysis skills by applying a feminist lens to the hyper-masculine film 300, specifically analyzing symbolic representations of power

EFSUMB Guidelines on Interventional Ultrasound (INVUS), Part VI - Ultrasound-guided vascular interventions

The sixth part of the Guidelines on Interventional Ultrasound produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) assesses the evidence for ultrasound guidance and assistance in vascular interventions. Based on convincing data, real-time sonographic guidance for central venous access is strongly recommended as a key safety measure. Systematic analysis of scientific literature shows that in difficult situations and special circumstances US guidance may also improve the efficacy and safety of peripheral venous and arterial access and endovascular interventions. Moreover, the recommendations of this guideline endorse the use of ultrasound to detect complications of vascular access and US-guided interventional treatment of arterial pseudoaneurysms.publishersversionPeer reviewe

Significant decline of mesospheric water vapor at the NDACC site near Bern in the period 2007 to 2018

The middle atmospheric water vapor radiometer MIAWARA is located close to Bern in Zimmerwald (46.88∘&thinsp;N, 7.46∘&thinsp;E; 907 m) and is part of the Network for the Detection of Atmospheric Composition Change (NDACC). Initially built in the year 2002, a major upgrade of the instrument's spectrometer allowed middle atmospheric water vapor to be continuously measured since April 2007. Thenceforward to May 2018, a time series of more than 11 years has been gathered, that makes a first trend estimate possible. For the trend estimation, a robust multilinear parametric trend model has been used. The trend model encompasses a linear term, a solar activity tracker, the El Niño–Southern Oscillation (ENSO) index and the Quasi-Biennial Oscillation (QBO) as well as the annual and semi-annual oscillation. In the time period April 2007 to May 2018 we find a significant decline in water vapor by -0.6±0.2&thinsp;ppm per decade between 61 and 72 km. Below the stratopause level (∼48 km) a smaller reduction of H2O of up to -0.3±0.1&thinsp;ppm per decade is detected.</p

Origin of solvent-induced polymorphism in self-assembly of trimesic acid monolayers at solid-liquid interfaces

Encoding information in the chemical structure of tectons is the pivotal strategy in self-assembly for the realization of targeted supramolecular structures. However, frequently observed polymorphism in supramolecular monolayers provides experimental evidence for a decisive additional influence of environmental parameters, such as solute concentration or type of solvent, on structure selection. While concentration-induced polymorphism is comparatively well understood, the thermodynamical and molecular origins of solvent-induced polymorphism remain elusive. To shed light on this fundamental aspect of self-assembly, we explore the solvent-induced polymorphism of trimesic acid (TMA) monolayers on graphite as prototypical example. Using the homologous series of fatty acids as solvents, TMA self-assembles into the anticipated chickenwire polymorph for longer chain fatty acids, whereas the more densely packed, but still porous flower polymorph emerges in shorter chain fatty acids. According to our initial working hypothesis, the origin of this solvent-induced polymorphism lies in a solvent-dependence of the free energy gain. Utilizing an adapted Born-Haber cycle constructed from measured TMA sublimation and dissolution enthalpies as well as Density Functional Theory calculated monolayer binding energies, we quantitatively assessed the self-assembly thermodynamics of both polymorphs in hexanoic, heptanoic, and nonanoic acid. Yet, in contrast to the experimental findings, these results suggest superior thermodynamical stability of the chickenwire polymorph in all solvents. On the other hand, additional experiments comprising variable temperature Scanning Tunneling Microscopy corroborate that the flower polymorph is thermodynamically most stable in hexanoic acid. To resolve this apparent contradiction, we propose a thermodynamical stabilization of the flower polymorph in hexanoic acid through the stereochemically specific co-adsorption of shape-matched solvent molecules in its unique smaller elongated pores. This alternative explanation gains further support from experiments with side-substituted hexanoic acid solvents. Combination of a quantitative thermodynamic analysis and studies with systematic variations of the solvent’s molecular structure holds great promise to enhance the understanding of thus far underexplored solvent effects

Diurnal changes in middle atmospheric H2O and O3: Observations in the Alpine region and climate models

International audienceIn this paper we investigate daily variations in middle atmospheric water vapor and ozone based on data from two ground-based microwave radiometers located in the Alpine region of Europe. Temperature data are obtained from a lidar located near the two stations and from the SABER experiment on the TIMED satellite. This unique set of observations is complemented by three different three-dimensional (3-D) chemistry-climate models (Monitoring of Stratospheric Depletion of the Ozone Layer (MSDOL), Laboratoire de Météorologie Dynamique Reactive Processes Ruling the Ozone Budget in the Stratosphere (LMDz-REPROBUS), and Solar Climate Ozone Links (SOCOL)) and the 2-D atmospheric global-scale wave model (GSWM). The first part of the paper is focused on the first Climate and Weather of the Sun-Earth System (CAWSES) tidal campaign that consisted of a period of intensive measurements during September 2005. Variations in stratospheric water vapor are found to be in the order of 1% depending on altitude. Meridional advection of tidal nature is likely to be the dominant driving factor throughout the whole stratosphere, while vertical advection becomes more important in the mesosphere. Observed ozone variations in the upper stratosphere and lower mesosphere show amplitudes of several percent in accordance with photochemical models. Variations in lower stratospheric ozone are not solely governed by photochemistry but also by dynamics, with the temperature dependence of the photochemistry becoming more important. The second part presents an investigation of the seasonal dependence of daily variations. Models tend to underestimate the H2O diurnal amplitudes, especially during summer in the upper stratosphere. Good agreement between models and observations is found for ozone in the upper stratosphere, which reflects the fact that the O3 daily variations are driven by the photochemistry that is well modeled

Beyond the Jaynes-Cummings model: circuit QED in the ultrastrong coupling regime

In cavity quantum electrodynamics (QED), light-matter interaction is probed at its most fundamental level, where individual atoms are coupled to single photons stored in three-dimensional cavities. This unique possibility to experimentally explore the foundations of quantum physics has greatly evolved with the advent of circuit QED, where on-chip superconducting qubits and oscillators play the roles of two-level atoms and cavities, respectively. In the strong coupling limit, atom and cavity can exchange a photon frequently before coherence is lost. This important regime has been reached both in cavity and circuit QED, but the design flexibility and engineering potential of the latter allowed for increasing the ratio between the atom-cavity coupling rate and the cavity transition frequency above the percent level. While these experiments are well described by the renowned Jaynes-Cummings model, novel physics is expected in the ultrastrong coupling limit. Here, we report on the first experimental realization of a superconducting circuit QED system in the ultrastrong coupling limit and present direct evidence for the breakdown of the Jaynes-Cummings model.Comment: 5 pages, 3 figure