Impact of Liquid Crystal Based Interference Mitigation and Precoding on the Multiuser Performance of VLC Massive MIMO Arrays

In visible light communication systems, the ability to suppress interference caused by other light sources is a major benefit towards performance improvements. Especially for large transmitter arrays or even multi-cell arrangements, the interference problem needs to be handled. In previous work, we have presented a liquid crystal display (LCD) used as an adaptive interference-suppression filter mounted in front of each photodetector. The display elements are switched on and off in such a way that light emitted by unwanted light sources ideally is blocked, but light emitted by desired light sources reaches the detector. The pattern generated by the LC display has strong impact on the system performance. In this paper, we propose combined precoding in conjunction with LCD-based interference suppression in order to increase the signal-to-interference-plus-noise ratio and to ensure user fairness in massive MIMO scenarios. The suggested precoding strategy uses a new heuristic optimization approach based on the Santa Claus problem on unrelated machines known from computer sciences, and employs only binary entries in the weighting matrix. Corresponding results are compared with a genetic evolutionary optimization strategy and with conventional zero-forcing precoding. Regarding performance evaluation, we perform numerical ray-tracing simulations and present a room-scale VLC testbed for experimental verification

Timing of Optical Maturation of Recently Exposed Material on Ceres

On Ceres, multispectral imaging data from the Dawn spacecraft show a distinct bluish characteristic for recently exposed material from the subsurface in, for example, crater ejecta. Ejecta blankets of presumably old craters show a more reddish spectrum. We selected areas in which fresh material from the Cerean subsurface was exposed at a specific time in the past, and no later geologic process is expected to have changed its surface composition or its cratering record. For each area, we determined two color ratios and the crater retention age. The measured color ratios show an exponential diminishment of the bluish characteristic over time. Although the cause of the color change remains uncertain, the time-dependent change in spectral properties is evident, which could help identify the process

Implementing an interprofessional point-of-care ultrasound protocol for dyspneic patients in an emergency department as a blended learning concept—Feasibility of Employing Thoracic Ultrasound in Shortness of Breath

ObjectiveDyspnea is a common symptom in the Emergency Department, with a wide variety of differential diagnoses. Previous research has demonstrated the diagnostic accuracy of Point-of-Care Ultrasound (POCUS) in this field of interest. Our goal was to better establish sonography in our emergency department with a practicable and time effective method. Therefore, we implemented a sonography protocol in an interprofessional emergency team using blended learning as a modern didactic approach and evaluated the learning and teaching success. We named the study FETUS, which stands for “Feasibility of Employing Thoracic Ultrasound in Shortness of Breath.”MethodsA demonstration of the POCUS protocol was given, followed by individual supervision during clinical routine. A written manual, a pocket card, and further materials for personal training supplemented the training. A post-training questionnaire measured several parameters regarding the training, e.g., subjective skill-acquisition or media use.Results32 medical and nursing staff participated in this study, 14 of whom completed the questionnaire. All training modalities offered were well received. A pre-post comparison of subjective sonographic competence shows a significant increase in both medical and nursing staff.The other items surveyed also indicate the success of the intervention undertaken.ConclusionThe use of different media as a blended learning approach can support the implementation of new measures in the ongoing working routine within an interprofessional team

Häusliche Pflege

HÄUSLICHE PFLEGE Häusliche Pflege / Bock, Isolde (Rights reserved) ( -

Absolute quantification of microparticles by flow cytometry in ascites of patients with decompensated cirrhosis: a cohort study

Background: Microparticles (MPs) are small (488.4 MP/mu L 94.7%, log rank p = 0.001) and such patients had a higher relative amount of ascites microparticles derived from neutrophils and lymphocytes. Low levels of ascites MPs, high MELD score and antibiotic treatment were independent risk factors for death within 30 days. Conclusions: Ascites MP levels predict short-term survival along with the liver function in patients with decompensated cirrhosis. Further studies which evaluate ascites MPs as disease specific biomarker with a validation cohort and which investigate its underlying mechanisms are needed. Neutrophils and lymphocytes contributed more frequently to the release of microparticles in patients with low ascites levels, possibly indicating an immune activation in this cohort