Benzene-1,4-Di(dithiocarboxylate) Linker-Based Coordination Polymers of Mn2+, Zn2+, and Mixed-Valence Fe2+/3.

Three new coordination polymers (CPs) constructed from the linker 1,4-di(dithiocarboxylate) (BDDTC2-)─the sulfur-analog of 1,4-benzenedicarboxylate (BDC2-)─together with Mn-, Zn-, and Fe-based inorganic SBUs are reported with description of their structural and electronic properties. Single-crystal X-ray diffraction revealed structural diversity ranging from one-dimensional chains in [Mn(BDDTC)(DMF)2] (1) to two-dimensional (2D) honeycomb sheets observed for [Zn2(BDDTC)3][Zn(DMF)5(H2O)] (2). Gas adsorption experiments confirmed a 3D porous structure for the mixed-valent material [Fe2(BDDTC)2(OH)] (3). 3 contains a 1:1 ratio of Fe2+/3+ ions, as evidenced by 57Fe Mössbauer, X-band EPR, and X-ray absorption spectroscopy. Its empirical formula was established by elemental analysis, thermal gravimetric analysis, infrared vibrational spectroscopy, and X-ray absorption spectroscopy in lieu of elusive single-crystal X-ray diffraction data. In contrast to the Mn- and Zn-based compounds 1 and 2, the Fe2+/3+ CP 3 showed remarkably high electrical conductivity of 5 × 10-3 S cm-1 (according to van der Pauw measurements), which is within the range of semiconducting materials. Overall, our study confirms that sulfur derivatives of typical carboxylate linkers (e.g., BDC) are suitable for the construction of electrically conducting CPs, due to acceptedly higher covalency in metal-ligand bonding compared to the electrically insulating carboxylate CPs or metal-organic frameworks. At the same time, the direct comparison between insulating CPs 1 and 2 with CP 3 emphasizes that the electronic structure of the metal is likewise a crucial aspect to construct electrically conductive materials.

Impact of right heart function on outcome in patients with functional mitral regurgitation and chronic heart failure undergoing percutaneous edge-to-edge-repair.

AIMS: To evaluate the impact of right ventricular dysfunction (RVD) on outcome after transcatheter mitral valve repair (TMVR) in patients with chronic heart failure (CHF) and severe functional mitral regurgitation (FMR). METHODS AND RESULTS: One hundred thirty patients (median age 72.7 ± 10.7 years; 63.8% male) at high operative risk (LogEuroSCORE 23.8 ± 13.9%) with FMR and CHF (left ventricular ejection fraction 32 ± 7%) were enrolled and separated into two groups according to the RVD. RVD was assessed by the tricuspid annular plane systolic excursion (TAPSE) method (A: TAPSE ≤ 16 mm, n = 58; B: TAPSE > 16 mm, n = 72). The rate of successful reduction of mitral regurgitation (MR ≤2+) by TMVR was similar in both groups (94.6% vs 91.2%; P: n.s.) with low in-hospital major adverse event rates. During a median follow-up period of 10.5 ± 4 months, the Kaplan-Meier analysis revealed a significantly higher all-cause mortality in group A (43.1% vs 23.6%; log-rank P = 0.039) and a significantly higher rate of hospital readmission due to congestive heart failure (56.9% vs 26.4%; log-rank P < 0.001). At long-term follow-up, 25% of patients in group A remained in NYHA functional class IV (none in group B). Preexisting RVD as assessed by TAPSE and Doppler tissue imaging (DTI-S') was an independent predictor of all-cause mortality after TMVR (hazard ratio 2.84; 95% confidence interval 1.15-7.65; P = 0.039; hazard ratio 4.70; 95% confidence interval 1.14-20.21; P = 0.044, respectively). CONCLUSIONS: Patients with CHF and RVD were with regard to functional capacity less often responder and showed an unfavorable long-term outcome. Thus, patients with CHF and RVD seem to benefit less frequently from TMVR.

Zirconium Oxynitride Thin Films for Photoelectrochemical Water Splitting.

Transition metal oxynitrides are a promising class of functional materials for photoelectrochemical (PEC) applications. Although these compounds are most commonly synthesized via ammonolysis of oxide precursors, such synthetic routes often lead to poorly controlled oxygen-to-nitrogen anion ratios, and the harsh nitridation conditions are incompatible with many substrates, including transparent conductive oxides. Here, we report direct reactive sputter deposition of a family of zirconium oxynitride thin films and the comprehensive characterization of their tunable structural, optical, and functional PEC properties. Systematic increases of the oxygen content in the reactive sputter gas mixture enable access to different crystalline structures within the zirconium oxynitride family. Increasing oxygen contents lead to a transition from metallic to semiconducting to insulating phases. In particular, crystalline Zr2ON2-like films have band gaps in the UV-visible range and are n-type semiconductors. These properties, together with a valence band maximum position located favorably relative to the water oxidation potential, make them viable photoanode candidates. Using chopped linear sweep voltammetry, we indeed confirm that our Zr2ON2 films are PEC-active for the oxygen evolution reaction in alkaline electrolytes. We further show that high-vacuum annealing boosts their PEC performance characteristics. Although the observed photocurrents are low compared to state-of-the-art photoanodes, these dense and planar thin films can offer a valuable platform for studying oxynitride photoelectrodes, as well as for future nanostructuring, band gap engineering, and defect engineering efforts.

Student tutors for hands-on training in focused emergency echocardiography--a randomized controlled trial.

BACKGROUND: Focused emergency echocardiography performed by non-cardiologists has been shown to be feasible and effective in emergency situations. During resuscitation a short focused emergency echocardiography has been shown to narrow down potential differential diagnoses and to improve patient survival. Quite a large proportion of physicians are eligible to learn focused emergency echocardiography. Training in focused emergency echocardiography usually comprises a lecture, hands-on trainings in very small groups, and a practice phase. There is a shortage of experienced echocardiographers who can supervise the second step, the hands-on training. We thus investigated whether student tutors can perform the hands-on training for focused emergency echocardiography. METHODS: A total of 30 volunteer 4th and 5th year students were randomly assigned to a twelve-hour basic echocardiography course comprising a lecture followed by a hands-on training in small groups taught either by an expert cardiographer (EC) or by a student tutor (ST). Using a pre-post-design, the students were evaluated by an OSCE. The students had to generate two still frames with the apical five-chamber view and the parasternal long axis in five minutes and to correctly mark twelve anatomical cardiac structures. Two blinded expert cardiographers rated the students' performance using a standardized checklist. Students could achieve a maximum of 25 points. RESULTS: Both groups showed significant improvement after the training (p < .0001). In the group taught by EC the average increased from 2.3±3.4 to 17.1±3.0 points, and in the group taught by ST from 2.7±3.0 to 13.9±2.7 points. The difference in improvement between the groups was also significant (p = .03). CONCLUSIONS: Hands-on training by student tutors led to a significant gain in echocardiography skills, although inferior to teaching by an expert cardiographer.

In vivo characterization of a versatile 8-channel digital biopotential recording system with sub-µVRMS input noise.

This work presents the design and testing of an integrated 8-channel CMOS biopotential recording chip, consisting of low-noise input stages, tunable second stage, a multiplexer, and two analog-to-digital converters (ADC). Through its variable supply concept, the integrated input-referred noise of the first stage is selectable from 1.5 down to 0.63 µVRMS (ISS = 200 µA), which is superior to standard laboratory recording systems. The device features variable lower and upper corner frequencies, and outputs two digital 16-bit data streams at 62.5 kS/s. The chip die was fabricated in X-Fab 0.35 µm CMOS technology and has an area of 10 mm2.

Micromonas (Peptostreptococcus) micros: unusual case of prosthetic joint infection associated with dental procedures.

Micromonas (Peptostreptococcus) micros is frequently associated with periodontal disease as well as respiratory, gastrointestinal and female genitourinary tract infections, but only rarely has been reported as a pathogenic agent of prosthetic joint infections. Here we describe a case of a 63-year-old woman with prosthetic joint infection of total hip arthroplasty caused by the anaerobic species Micromonas micros, associated with tooth extraction. Samples obtained intraoperatively and from the oral cavity were positive for the presence of M. micros by culture and by real-time PCR. This case report indicates that infections of prosthetic joints can be associated with dental procedures and that sensitive molecular techniques are necessary for their routine diagnostic.