[Imaging in intensive care units]. / Bildgebung auf der Intensivstation.

Imaging is essential in the diagnosis and treatment of critically ill patients. Although bedside ultrasound and chest x­rays are the major tools in the initial assessment, there are a variety of imaging options available to physicians in the intensive care unit such as computed tomography, magnetic resonance imaging, or nuclear medicine. Bedside diagnostic tools or radiology intervention procedures also play an important role in the management of critically ill patients. The choice of imaging modality is sometimes difficult and should be based on current recommendations or guidelines, available equipment, and the experience of the examiner. With the increasing importance of costs, the diagnostic and therapeutic benefits of the imaging process must be maximized in line with minimizing costs. The various indications, strengths, and weaknesses of the imaging modalities are summarized and the diagnostic findings using clinical examples are discussed. The focus of this article is on imaging of the thorax and the diagnostic imaging methods used in the intensive care unit.

[Ten key messages regarding embolic stroke of undetermined source and cryptogenic stroke]. / 10 Kernaussagen zum Embolic Stroke of Undetermined Source und kryptogenen Schlaganfall.

Cryptogenic stroke is a cerebral infarction where no source of cardioembolic events, no microangiopathy with lacunar infarcts, and no macroangiopathy with high-grade stenosis of the cerebral arteries can be detected. However, cryptogenic stroke is not operationally defined. The new concept of the embolic stroke of undetermined source (ESUS) is defined as a nonlacunar stroke in cerebral imaging and exclusion of significant stenosis of the cerebral arteries by angiographic or ultrasound techniques. Cardiac embolic sources must be excluded by ECG monitoring and echocardiography. At the moment, secondary prevention in patients with ESUS is performed with acetylsalicylic acid. The question of whether non-vitamin K oral anticoagulants (NOAK) are effective in these patients for secondary prevention is currently being investigated in randomized trials. The acute treatment of cryptogenic stroke/ESUS does not differ from other stroke subtypes because the stroke etiology is often not known initially, but can be identified during the course of treatment in the stroke unit.

High temperature Seebeck coefficient and resistance measurement system for thermoelectric materials in the thin disk geometry.

A versatile apparatus to measure the cross-plane Seebeck coefficient and the resistivity of bulk samples shaped as disks or thin plates, over a temperature range of 300 K-620 K with possible extension to higher temperatures, is presented. It is constructed from readily available equipment and instrumentation with parts that are easily manufactured. The Seebeck coefficient is measured over an average region of the sample under steady-state conditions. The sample resistance is measured using a four-point alternating current method and scaled to room temperature measurements with known geometry to calculate resistivity. A variety of sample shapes are supported. Most importantly, the support of the thin disk geometry allows for the very same samples to be used in a laser flash instrument. The design allows for rough vacuum, high vacuum, or purging with inert gases in the sample chamber. Measurements on thermoelectric ZnSb and a Ni reference material are presented.

Electronic structure of thermoelectric Zn-Sb.

The electronic structures of the two main compounds of the binary zinc antimonides that are stable at room temperature, Zn(1)Sb(1) and ß-Zn(4)Sb(3), were probed with x-ray photoelectron spectroscopy. Additionally, electron energy loss measurements and density functional theory calculations are presented. The compounds are found to share a very similar electronic structure. They both feature only small charge transfers and differ moderately in their screening potentials. These results are in line with recent theoretical works on the Zn-Sb system and are discussed in light of the reported thermoelectric performance of the materials.

Calorimetric evidence for a Fulde-Ferrell-Larkin-Ovchinnikov superconducting state in the layered organic superconductor kappa-(BEDT-TTF)2Cu(NCS)2.

The specific heat of the layered organic superconductor kappa-(BEDT-TTF)(2)Cu(NCS)(2), where BEDT-TTF is bisethylenedithio-tetrathiafulvalene, has been studied in magnetic fields up to 28 T applied perpendicular and parallel to the superconducting layers. In parallel fields above 21 T, the superconducting transition becomes first order, which signals that the Pauli-limiting field is reached. Instead of saturating at this field value, the upper-critical-field increases sharply and a second first-order transition line appears within the superconducting phase. Our results give strong evidence that the phase, which separates the homogeneous superconducting state from the normal state is a realization of a Fulde-Ferrell-Larkin-Ovchinnikov state.