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Pacemaker Versus Defibrillator Therapy in Patients Eligible for Cardiac Resynchronisation Therapy: Evidence from the German Device Registry
No full textBackground: According to current guidelines, cardiac resynchronisation therapy (CRT) is recommended in patients with significantly impaired left ventricular systolic function and left bundle branch block. However, the decision between pacemaker (CRT-P) and defibrillator (CRT-D) in patients eligible for CRT remains a matter of debate. Register data have shown a higher all-cause mortality in CRT-P in comparison to patients with a CRT-D. Here, we investigated clinical determinants of the selection of CRT-P vs. CRT-D and clinical outcome in large registry data from a multi-centre ‘real-life’ registry on patients with CRT defibrillator or pacemaker therapy. Methods: The German Device Registry (DEVICE) is a nationwide, prospective registry with one-year follow-up investigating 5451 patients receiving device implantations in 50 German centres. The present analysis of DEVICE focused on all patients from the register receiving cardiac resynchronization therapy. Results: Out of 1603 patients receiving cardiac resynchronisation therapy, 1536 (95.8%) received a CRT defibrillator system and 67 (4.2%) a CRT pacemaker system. Patients in the CRT-P group had a significantly better left ventricular systolic function compared to the CRT-D group (median 35% vs. 25%), and significantly less often had a history of myocardial infarction (9.0% vs. 25.2%). A preexisting pacemaker and a history of stroke/peripheral embolism were identified as determinants for the selection of CRT-P vs. CRT-D. Overall mortality after one-year follow-up was 8.0%. Patients with ischemic cardiomyopathy receiving CRT-P therapy had a higher one-year mortality than patients receiving CRT-D (21.2% vs. 8.9%, p = 0.020). On the other hand, patients with non-ischemic cardiomyopathy did not display differences between these two treatment groups (CRT-P 8.1%, CRT-D 6.6%, p = 0.72). Conclusions: Data from the German device registry show that most patients receiving cardiac synchronization therapy have an implanted CRT-D system. In comparison to patients with CRT-D, those with CRT-P more often had a non-ischemic cardiomyopathy and a preexisting pacemaker system. The outcomes between these two treatment groups were different as regards ischemic cardiomyopathy only
Quantum control in size selected semiconductor quantum dot thin films
No full textWe introduce a novel technique for coherent control that employs resonant internally generated fields in CdTe quantum dot (QD) thin films at the L-point. The bulk band gap of CdTe at the L-point amounts to 3.6 eV, with the transition marked by strong Coulomb coupling. Third harmonic generation (λ_3 = 343 nm, hν = 3.61 eV) for a fundamental wavelength of λ_1 = 1,030 nm is used to control quantum interference of three-photon resonant paths between the valence and conduction bands. Different thicknesses of the CdTe QDs are used to manipulate the phase relationship between the external fundamental and the internally generated third harmonic, resulting in either suppression or strong enhancement of the resonant third harmonic, while the nonresonant components remain nearly constant. This development could pave the way for new quantum interference–based applications in ultrafast switching of nanophotonic devices
Regulations on Sex Toy Industry in Europe
No full textThe European sex toy market is witnessing a strategic sales growth. The lockdown to contain the Corona Pandemic situation is boosting the market scenario. Countries such as the UK, Germany, France, Italy, and Spain are key growing countries driving the demand for sex toys in Europe. Against this background, this article explores the sex toy industry in Europe and the few laws that govern it. It discusses that a lack of regulation of these products has allowed manufacturers to exploit the inexpensive but highly toxic materials used in the making of sex toys to the detriment of consumers, and the implications inclined towards improving the protection of consumers in Europe
Stealthy Hyperuniform Surface Structures for Efficiency Enhancement of Organic Solar Cells
No full textLow absorption in the thin active layer of conventional organic solar cells limits their power conversion efficiency. Structured surface layers are a common approach to diffracting incoming light, thus elongating its path through the active layer, thereby increasing the probability of absorption and hence the power conversion efficiency. While standard periodic structures diffract light into discrete angles, making them optimal only for specific wavelengths, random structures induce broadband, but nontailorable diffraction. Thus, instead, a stealthy hyperuniform structure, designed to exhibit beneficial diffraction properties is implemented: it directs the light into a predefined range of higher angles, prevents diffraction into small angles, and is thus ideal for a strong active path length enhancement. After numerical optimization of the feature height and diameter, the stealthy hyperuniform structure is fabricated in silicon by electron beam lithography and subsequently transferred into a transparent polymer via replica molding. Experimental diffraction images reveal a circular symmetric spectrum, inducing diffraction independent of the azimuthal angle and polarization of the incident light. The application of the stealthy hyperuniform structure on a poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl)benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione)]:3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d’]-s-indaceno[1,2-b:5,6-b′]dithiophene organic solar cell leads to a sharp increase in current density and power conversion efficiency
The significance of structural rich club hubs for the processing of hierarchical stimuli
No full textThe brain's structural network follows a hierarchy that is described as rich club (RC) organization, with RC hubs forming the well-interconnected top of this hierarchy. In this study, we tested whether RC hubs are involved in the processing of hierarchically higher structures in stimulus sequences. Moreover, we explored the role of previously suggested cortical gradients along anterior-posterior and medial-lateral axes throughout the frontal cortex. To this end, we conducted a functional magnetic resonance imaging (fMRI) experiment and presented participants with blocks of digit sequences that were structured on different hierarchically nested levels. We additionally collected diffusion weighted imaging data of the same subjects to identify RC hubs. This classification then served as the basis for a region of interest analysis of the fMRI data. Moreover, we determined structural network centrality measures in areas that were found as activation clusters in the whole-brain fMRI analysis. Our findings support the previously found anterior and medial shift for processing hierarchically higher structures of stimuli. Additionally, we found that the processing of hierarchically higher structures of the stimulus structure engages RC hubs more than for lower levels. Areas involved in the functional processing of hierarchically higher structures were also more likely to be part of the structural RC and were furthermore more central to the structural network. In summary, our results highlight the potential role of the structural RC organization in shaping the cortical processing hierarchy
Isolierung, Strukturaufklärung und Struktur-Wirkungs-Beziehungen antiprotozoaler Alkaloide aus Pachysandra terminalis sowie deren saisonale, organ- und standortbedingte Variabilität
No full textPflanzen der Familie Buxaceae enthalten Amino-Nortriterpene mit vielversprechender Wirkung
gegen Trypanosoma brucei rhodesiense und Plasmodium falciparum. In der vorliegenden Arbeit
lag der Fokus daher auf der Isolierung solcher Substanzen aus Pachysandra terminalis
(Buxaceae) sowie auf deren antiprotozoaler Wirkung. Insgesamt konnten 20 Alkaloide aus
Pachysandra terminalis isoliert und ihre Strukturen mittels UHPLC/+ESI-QqTOF-MS/MS sowie
1D- und 2D-NMR-Messungen aufgeklärt werden. Einige der Alkaloide zeigten in in vitro-Assays
vielversprechende antiprotozoale Aktivitäten. Erste (quantitative) Struktur-Wirkungs-
Beziehungen (QSARs) der Pachysandra-Alkaloide konnten mithilfe von 3D-QSAR-Modellen
abgeleitet werden. Zudem wurde Pflanzenmaterial von Pachysandra terminalis im Verlauf eines
Jahres an zwei Standorten in Münster (Deutschland) geerntet und mithilfe multivariater
Datenanalysen saisonale sowie organ- und standortabhängige Veränderungen im Alkaloidprofil
untersucht
Sacubitril Does Not Exert Proarrhythmic Effects in Combination with Different Antiarrhythmic Drugs
No full textBackground: Previous studies suggest a direct effect of sacubitril on cardiac electrophysiology and indicate potential arrhythmic interactions between sacubitril and antiarrhythmic drugs. Therefore, the aim of this study was to explore the electrophysiologic effects of combining sacubitril with the antiarrhythmic drugs d,l-sotalol and mexiletine in isolated hearts. Methods and results: A total of 25 rabbit hearts were perfused using a Langendorff setup. Following baseline data collection, hearts were treated with mexiletine (25 µM, 13 hearts) or d,l-sotalol (100 µM, 12 hearts). Monophasic action potential demonstrated an abbreviation of action potential duration (APD90) after administration of mexiletine. Spatial dispersion of repolarization remained unchanged after mexiletine treatment, whereas effective refractory periods (ERP) were significantly prolonged. D,l-sotalol prolonged cardiac repolarization and amplified spatial dispersion. Further infusion of sacubitril (5 µM) led to a significant reduction in APD90 and ERP in the mexiletine group. In the d,l-sotalol group, additional administration of sacubitril shortened cardiac repolarization duration without affecting spatial dispersion. No proarrhythmic effect was observed after mexiletine treatment as assessed by a predefined pacing protocol. Additional sacubitril treatment did not increase ventricular vulnerability. When potassium concentration was reduced, 30 episodes of torsade de pointes tachycardia occurred after d,l-sotalol treatment. Additional sacubitril treatment significantly suppressed torsade de pointes tachycardia (eight episodes) in the d,l-sotalol-group. Conclusions: In class IB- and class III-pretreated hearts, sacubitril shortened refractory periods and cardiac repolarization duration. The combination of sacubitril with the antiarrhythmic drugs d,l-sotalol and mexiletine demonstrates a safe electrophysiologic profile and sacubitril reduces the occurrence of class III-related proarrhythmia, i.e., torsade de pointes tachycardia
Text quality and changing perceptions of teacher feedback and affective-motivational variables: a study with secondary EFL students
No full textIntroduction: Feedback can support students' writing and has the potential to enhance writing motivation and reduce writing anxiety. However, for feedback to fulfill its potential, it has to be accepted by students and perceived as motivating. Methods: In this study, we investigate changes in less proficient English as a foreign language (EFL) students' (N = 53) writing motivation and affect, as well as their perceptions of teacher feedback and how these relate to students’ argumentative text quality. Measurements were taken before EFL teachers attended a professional learning intervention on feedback (T1) and 8 months later (T2). Results: From T1 to T2, students felt that general feedback quality improved, their writing self-efficacy increased, and their writing anxiety decreased. However, no significant changes in text quality could be observed between T1 and T2, and students continued to struggle with creating structure and coherence in their texts. Regression analyses revealed that feedback perceptions and affective-motivational variables did not predict students' text quality at T1. Yet at T2, students' perception of general feedback quality and the effect of feedback on writing motivation were significant predictors of text quality; self-efficacy and writing anxiety were not.
Discussion: Our results suggest that more attention needs to be paid to feedback’s motivational impact, especially among less proficient EFL writers
The jadeitites from Syros and Tinos, Cycladic Blueschist Unit, Greece: field observations, mineralogical, geochemical and geochronological characteristics
No full textThis study illustrates the field relationships of jadeitite-bearing block-in-matrix sequences on Syros and Tinos, Cycladic Blueschist Unit, and adds additional U–Pb zircon ages for jadeitites to the geochronological database. The results confirm the importance of Cretaceous (c. 80 Ma) and Eocene (c. 50 Ma) processes in their geological evolution. Interpretations suggesting that the jadeitites were formed by complete metasomatic replacement of a pre-existing rock are not fully supported by field observations. In at least some cases, the formation of jadeitite is likely due to precipitation from Na-Al-Si-rich aqueous fluids, which also caused variable metasomatic alteration of the host rock. Unambiguous age constraints for formation of the Syros and Tinos jadeitites are not available. A relationship to Eocene blueschist facies metamorphism recorded in the associated metamafic rocks seems plausible. However, since high-pressure overprinting of pre-Eocene jadeitite is also conceivable, there is a much larger time window for jadeitite formation, framed by Cretaceous (c. 80–76 Ma) protolith ages of various mélange blocks and the waning stages of blueschist facies metamorphism (c. 40 Ma). Field observations are consistent with the interpretation that the mélange-like occurrences on Syros and Tinos record, to varying extent, multi-stage processes that include detachment of mafic rocks from the subducting plate, local infiltration of Na-Al-Si-rich aqueous fluids, exhumation via a serpentinitic matrix in a subduction channel and reworking of the primary block-in-matrix fabric by sedimentary or tectonic processes during accretionary wedge formation
