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The quest to develop efficient electrocatalysts for water‐splitting is still an ongoing challenge. Intense efforts have been dedicated over the years to design effective methods to improve the electrocatalytic performances. In recent times, the single‐source (molecular) precursor (SSP) approach has gained enormous attention from the scientific community as it operates at low temperatures and leads to the formation of unique nanostructured materials, with fine‐tuned chemical and physical properties, resulting in high and stable catalytic activities. Herein, the recent developments in molecule‐to‐material chemistry and their applications toward the oxygen evolution reaction, hydrogen evolution reaction, and overall water‐splitting are summarized. Furthermore, the review focuses on understanding the reconstruction process of the SSP‐derived materials and the adopted techniques (in situ and ex situ) to obtain insights into the active structures for catalysis. The future possibilities of applying these materials for value‐added organic electro‐oxidation/reduction reactions are also explored.

Four commercial titanium dioxide (TiO2) photocatalysts, namely P25, P90, PC105, and PC500, were immobilized onto steel plates using a sol-gel binder and investigated for phenol degradation under 365 nm UV-LED irradiation. High-performance liquid chromatography (HPLC) and total organic carbon (TOC) analyses were performed to study the impact of three types of oxygen sources (air, dispersed synthetic air, and hydrogen peroxide) on the photocatalytic performance. The photocatalyst films were stable and there were significant differences in their performance. The best result was obtained with the P90/UV/H2O2 system with 100% degradation and about 70% mineralization within 3 h of irradiation. The operating conditions varied, showing that water quality is crucial for the performance. A wastewater treatment plant was developed based on the lab-scale results and water treatment costs were estimated for two cases of irradiation: UV-LED (about 600 EUR/m3) and sunlight (about 60 EUR/m3). The data show the high potential of immobilized photocatalysts for pollutant degradation under advanced oxidation process (AOP) conditions, but there is still a need for optimization to further reduce treatment costs.

Background: Detection of atrial fibrillation (AF) is one of the primary diagnostic goals for patients on a stroke unit. Physician-based manual analysis of continuous ECG monitoring is regarded as the gold standard for AF detection but requires considerable resources. Recently, automated computer-based analysis of RR intervals was established to simplify AF detection. The present prospective study analyzes both methods head to head regarding AF detection specificity, sensitivity, and overall effectiveness. Methods: Consecutive stroke patients without history of AF or proof of AF in the admission ECG were enrolled over the period of 7 months. All patients received continuous ECG telemetry during the complete stay on the stroke unit. All ECGs underwent automated analysis by a commercially available program. Blinded to these results, all ECG tracings were also assessed manually. Sensitivity, specificity, time consumption, costs per day, and cost-effectiveness were compared. Results: 216 consecutive patients were enrolled (70.7 ± 14.1 years, 56% male) and 555 analysis days compared. AF was detected by manual ECG analysis on 37 days (6.7%) and automatically on 57 days (10.3%). Specificity of the automated algorithm was 94.6% and sensitivity 78.4% (28 [5.0%] false positive and 8 [1.4%] false negative). Patients with AF were older and had more often arterial hypertension, higher NIHSS at admission, more often left atrial dilatation, and a higher CHA2DS2-VASc score. Automation significantly reduced human resources but was more expensive compared to manual analysis alone. Conclusion: Automatic AF detection is highly specific, but sensitivity is relatively low. Results of this study suggest that automated computer-based AF detection should be rather complementary to manual ECG analysis than replacing it. [ABSTRACT FROM AUTHOR]

Main criticisms about single-pass VDD stimulation in patients with AV block and normal sinus node function concern atrial undersensing in a lead with floating atrial electrodes, and loss of AV synchrony if sinus node dysfunction develops after implantation. We evaluated the concept of a preshaped singlepass lead designed to place the atrial ring electrodes in a constant position close to, or in contact with, the atrial wall. A preshaped lead (Model 2775, Medtronic Inc.) was implanted in 14 patients and followed for up to 2 years. Mean P wave amplitudes (PWAs) were 3.1 mVat implantation, 1.2 mV at predischarge, and 1.3 mV after 12 months. In all patients, minimal PWAs were well above maximal atrial sensitivity of the pacemaker in all body positions during the complete follow-up; atrial undersensing was not observed. Effective atrial stimulation was possible in all patients at implantation (mean stimulation threshold 2.5 V at 0.50 ms), in 11 patients on the first day after implant (mean stimulation threshold 0.22 ms at 5.0 V), in 10 patients after 1 month (mean stimulation threshold 0.57 ms at 5.0 V), and in 10 patients after 1 year (mean stimulation threshold 0.65 ms at 5.0 V). Intermittent phrenic nerve stimulation could be provoked in six patients. In conclusion, the concept of a preshaped single-pass lead facilitated implantation, improved atrial sensing performance, and allowed atrial stimulation in some patients. Still, further improvements are necessary to decrease the atrial stimulation thresholds to acceptable values in all patients. [ABSTRACT FROM AUTHOR]

The article focuses on pacemakers event counters. Pacemaker performance in terms of stimulation threshold, sensing amplitudes, impedances, etc., can be evaluated in modern devices telemetrically during a follow-up visit by multiple measurements and maneuvers, but only the rhythm state of the patient and pacemaker function during a time period of a few minutes will be taken into account. VDD single lead systems represent an excellent example of pacemaker systems in which diagnostic pacemaker functions are crucial to determine long-term deyice performance.

Abstract Electrochemical water oxidation with single atom catalysts (SACs) has garnered immense interest because of their high atom utilization, extraordinary activity, and elucidation of the reaction mechanism. In SACs, while the atomic sites offer active centers for substrate binding and reaction intermediates, their interaction with the solid support is crucial for the stabilization and enhancement of catalytic activity. Coordinated elements surrounding the atomic site create a ligand‐like environment that influences electrochemical properties. As a result, tuning the coordination environment of SACs allows for modulation of their oxygen evolution reaction (OER) activity. In light of this, the question arises: What is the role of the support in stabilizing single atoms (SAs) and controlling their electrochemical activity during water oxidation? This review addresses this question using recent examples. Spectroscopic characterizations and density functional theory (DFT) calculations provide a direct answer: In SACs, the atomic centers exhibit strong interactions with the support via neighboring atoms, influencing OER activity.