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Cuprate coated conductors are promising materials for the development of large-scale applications, having superior performance over other superconductors. Tailoring their vortex pinning landscape through nanostructure engineering is one of the major challenges to fulfill the specific application requirements. In this work, we have studied the influence of the growth temperature on the generation of intrinsic pinning defects in YBa2Cu3O7-δ films grown by chemical solution deposition using low Ba precursor solutions. We have analysed the critical current density as a function of the temperature, applied magnetic field magnitude and orientation, J c(T,H,θ), to elucidate the nature and strength of pinning sites and correlate the microstructure of the films with their superconducting performance. An efficient pinning landscape consisting of stacking faults and associated nanostrain is naturally induced by simply tuning the growth temperature without the need to add artificial pinning sites. Samples grown at an optimized temperature of 750 °C show very high self-field J c values correlated with an overdoped state and improved J c(T,H,θ) performances., This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom Research and Training Programme 2014–2018 and 2019–2020 under Grant Agreement No. 633 053. The views and opinions expressed herein do not necessarily reflect those of the European Commission. TEM analysis was funded from the EU Horizon 2020 research and innovation program under grant agreement 823717—ESTEEM3. The authors acknowledge financial support from Spanish Ministry of Economy and Competitiveness through the 'Severo Ochoa' Programme for Centres of Excellence in R&D (SEV-2015-0496 and CEX2019-000917-S), SuMaTe RTI2018-095853-B-C21, co-financed by the European Regional Development Fund), the Catalan Government with Grant 2017-SGR-1519 and the EU COST action NANOCOHYBRI CA16218. We also acknowledge the Scientific Services at ICMAB. J A like to thank the UAB PhD program in Materials Science., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).

Among other Fe-based superconductors, Fe(Se,Te) is particularly interesting because of the low structural anisotropy, large upper critical fields, low field dependence of the critical current density and low toxicity. It can also be grown as an epitaxial film on a metallic oriented substrate, making the fabrication of a Fe-based coated conductor (CC) possible. Less strict requirements on the template microstructure allow for the design of a simplified design compared to REBCO CCs. This design requires a buffer layer to promote the oriented growth of the superconducting film and avoid diffusion from the metallic template. In this work, CeO2 based buffer layers are prepared on single crystals via two chemical deposition techniques, metal organic decomposition (MOD) and polymer assisted deposition (PAD). With the design of a suitable thermal treatment, it is possible to obtain oriented buffers with large flat grains and low values of surface roughness. Fe(Se,Te) films are deposited on these templates via laser deposition, and excellent samples are obtained when a Fe(Se,Te) seed layer is used to favour chemical matching with the buffer: sharp superconducting transitions around 16 K and critical current densities exceeding 1 MA cm-2 at 4.2 K in self-field are observed. These results are the demonstration of the feasibility of a Fe-based CC architecture, with all the relative advantages concerning process simplification and cost reduction.

We present a novel compact wideband waveguide T-junction power divider, especially suited for millimeter-wave and THz frequencies. It incorporates substrate-based elements into a waveguide structure to provide the output port's isolation and matching. The internal port is introduced at the apex of the T-junction formed as an E-probe on a substrate. This facilitates efficient coupling of the reflected energy from the output port to a novel thin-film-based resistive termination integrated with the E-probe onto the same substrate and fabricated by means of thin-film technology. A power divider was designed, simulated, and fabricated for the frequency band 150–220 GHz to experimentally verify the theoretical and simulated performance. The results showed excellent agreement between the simulations and measurements with the devices demonstrating a remarkable return loss of 20 dB for both the input and output ports for a three-port device with equal split and isolation better than 17 dB between the output ports. Furthermore, the measured insertion loss is less than 0.3 dB and the amplitude and phase imbalance are 0.15 dB and 0°, respectively. Moreover, the divider's remarkable tolerance to the dimensions and sheet resistance of the resistive material of the built-in absorbing load makes the device a very practical component for millimeter-wave and THz systems, in particular radio-astronomy receivers.

We investigated the integration of transient liquid-assisted growth (TLAG) approach for epitaxial YBa2Cu3O7−x (YBCO) films by physical deposition methodologies (pulsed laser deposition (PLD)), as an additional opportunity for high-throughput growth of YBCO. As a prerequisite, highly flat and amorphous YBCO precursor films were deposited by PLD at temperatures below 400 °C on single-crystalline SrTiO3 (STO) and LaMnO3 (LMO)/STO, as well as industrial coated conductor architectures. Contrary to TLAG based on chemical solution deposition, where BaCO3 elimination is a key factor for the YBCO growth, TLAG-PLD growth is controlled by the transformation of Ba-Cu-O (s) to a transient liquid. High-quality c-axis YBCO films were successfully grown on different substrates, as demonstrated by high-resolution x-ray diffraction and transmission electron microscopy. In-situ resistance measurements revealed that the growth rates around 1000 nm s−1 can be achieved, outperforming the capabilities of standard PLD growth of REBa2Cu3O7 films by few orders of magnitude. Experimental conditions such as temperature, oxygen partial pressure, and heating ramp, were optimized to obtain critical temperature (T c) values up to 90 K. Critical current densities of 15 MA cm−2 at 5 K and 1.7 MA cm−2 at 77 K were obtained for YBCO films of 450 nm on LMO/STO., The authors acknowledge European Research Council for the ULTRASUPERTAPE project (ERC-2014-ADG-669504), IMPACT project (ERC-2019-PoC-874964) and SMS-INKS project (ERC-2022-PoC-101081998), as well as the EU COST actions CA16218 (NANOCOHYBRI), CA20116 (OPERA) and CA21144 (SUPERQUMAP). We also thank financial support from the Spanish Ministry of Economy and Competitiveness, and Spanish Ministry of Science, Innovation and Universities through the 'Severo Ochoa' Programme for Centres of Excellence in R&D (SEV-2015-0496 and CEX2019-000917-S), FUNFUTURE-FIP-2020-DATOPTICON, SUPERENERTECH project (PID2021-127297OB-C21), and SUMATE project (RTI2018-095853-B-C21, co-financed by the European Regional Development Fund). We also acknowledge support from the Catalan Government with 2017-SGR-1519 and the Catalan energy network XRE4S (2018 XARDI 00002). A Q thanks the Spanish Ministry of Science, Innovation and Universities for his 'Juan de la Cierva' postdoctoral fellowship (Grant No. IJC2018-035034-I). L S acknowledges financial support from Spanish Ministry of Science, Innovation and Universities through the FPI grants PRE2019-090621. Dr Silvia Rasi and Dr Roxana Vlad are thanked for fruitful discussions. We acknowledge the Scientific Services at ICMAB and ICN2 Electron Microscopy Division. Authors also acknowledge the use of instrumentation as well as the technical advice provided by the National Facility ELECMI ICTS, node 'Laboratorio de Microscopías Avanzadas' at University of Zaragoza. SuNAM Co. is acknowledged for providing metallic substrates., With funding from the Spanish government through the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000917-S).

Pt–Re bimetallic catalysts have many applications, ranging from catalytic reforming to the reduction of carboxylic acid derivatives. However, the exact role of Re in these systems has remained a ma...

Development of modulators targeting specific interactions of ubiquitin‐based conjugates with their partners is a formidable task since it requires a suitable screening assay and homogeneous ubiquitin conjugates. We developed a novel high‐throughput strategy for screening ligands for Lys48‐linked tetraubiquitin chain in a relatively simple, fast, and affordable manner. This approach combined with a state‐of‐the‐art toolbox of chemical protein synthesis and a specially optimized Cys deprotection protocol enabled us to design highly potent, Lys48‐linked tetraubiquitin chain selective “next generation” dimeric peptide modulators. The dimeric peptide exhibited cancer cell permeability and induced cell death with higher efficiency compared to its monocyclic analogue. These features make our dimeric peptide a promising candidate for further studies using in vivo models. Our assay can be adopted for other various ubiquitin chains in their free or anchored forms as well as conjugates for Ub‐like modifiers., A fluorescence‐based competitive assay was developed, which enabled the high‐throughput screening of various cyclic peptides targeting the Lys48‐linked tetraubiquitin chain. This assay combined with chemical tools enabled the design of a potent dimeric cyclic peptide, which induced cell death with higher efficiency compared to its monocyclic analogue.

We report on a novel waveguide-to-substrate transition with prospective use for broadband mixer design. The transition employs a substrateless finline, i.e., a unilateral finline structure with the substrate removed between the fins. This distinctive feature diminishes the overall insertion loss and facilitates matching with the waveguide. The transition is designed on a thin silicon substrate covered by a superconducting niobium thin layer. An auxiliary Au layer situated on top of the Nb layer provides grounding for the fins and facilitates the mounting process in the split-block waveguide mount. Aiming to compare simulations with measurements, a back-to-back transition arrangement for the 211–373 GHz frequency band was designed, fabricated, and characterized at cryogenic temperatures. The simulation results for the back-to-back structure show an insertion loss of less than 0.6 dB in the whole band, i.e., 0.3 dB per transition. Furthermore, a remarkable fractional bandwidth of 55% with a return loss better than 15 dB is predicted. Experimental verification shows consistent results with simulations.

We report on a novel compact wideband 90 degrees twist with performance tolerant to small geometry variation and hence improved manufacturability through direct milling. The experimental verification shows 44% fractional bandwidth with return loss better than 20 dB over the 140-220 GHz band. The performance, compactness, and tolerance to manufacturing inaccuracy make it very suitable for use in various waveguide systems from microwave to millimeter-wave range.

Amplitude integrated EEG (aEEG) is increasingly utilized in preterm infants. The aim of the study was to evaluate whether semiquantitative visual assessment of aEEG background during the first 72 hours of life is associated with long-term outcome in a group of premature infants born less than 28 weeks’ gestation. Infants were prospectively enrolled and monitored in the first 72 hours after birth. aEEG was classified daily according to background activity, appearance of cyclical activity and presence of seizures activity. Log-rank and multivariable cox analysis were used to explore associations of background aEEG activity with short and long-term outcome. Overall, 51 infants were enrolled into the study. Depressed aEEG background on the third day of life was associated with poor outcome ( P = .028). Similarly, absence of cycling on the third day of life was associated with death or poor outcome ( P = .004 and .012, respectively). In different multivariable models adjusted for gestational age, severe intraventricular hemorrhage or use of sedative medication, neither background nor cycling activities were associated with outcome. Depressed aEEG background and absence of aEEG cycling on the third day of life are associated with poor outcome in univariable analysis. Although continuous aEEG monitoring of premature infants can provide real-time assessment of cerebral function, its use as a predictive tool for long-term outcome using visual analysis requires caution as its predictive power is not greater than that of gestational age or intraventricular hemorrhage.

Stabilization of single metal atoms is a persistent challenge in heterogeneous catalysis. Especially supported late transitions metals are prone to undergo agglomeration to nanoparticles under reducing conditions. In this study, nitrogen-rich covalent triazine frameworks (CTFs) are used to immobilize iridium complexes. Upon reduction at 400°C, immobilized Ir(acac)(COD) on CTF does not form nanoparticles but transforms into a highly active Ir single atom catalyst. The resulting catalyst systems outperforms both the immobilized complex and supported nanoparticles in the dehydrogenation of formic acid as probe reaction. This superior performance could be traced back to decisive changes of the coordination geometry positively influencing activity, selectivity and stability. Spectroscopic analysis reveals an increase of electron density on the cationic iridium site by donation from the CTF macroligand after removal of the organic ligand sphere from the Ir(acac)(COD) precursor complex upon reductive treatment. This work demonstrates the ability of nitrogen moieties to stabilize molecular metal species against agglomeration and opens avenues for catalysts design using isolated sites in high-temperature applications under reducing atmosphere.

Chemical solution deposition of Gd-doped YBCO, Y1GdyBa2Cu3O7&minus, &delta, (YBCO-Gd), film was carried out following the metal-organic decomposition approach and in situ route. Two dopant concentrations, 5 and 10 mol %, were evaluated. The morphology and crystalline structure of the superconductor films were deeply investigated. In general, a homogeneous and well c-axis oriented film was observed by using scanning and transmission electron microscopy (SEM and TEM) and X-ray diffraction. However, compared to pure YBCO, YBCO-Gd samples showed an increased stacking faults concentration, as recognized by TEM. X-ray photoelectron spectroscopy allowed studying the Gd distribution in the films and gathered information about the Gd electronic environment. Superconducting properties were evaluated at different temperatures, magnetic field directions, and intensities. Higher zero-field critical current densities were measured with respect to undoped samples in the temperature range from 10 to 77 K with both Gd concentrations (i.e., 28, 27, and 13 MA&middot, cm&minus, 2, respectively, for YBCO-Gd 5%, YBCO-Gd 10%, and undoped YBCO at 10 K in self field condition). At low temperatures, this improvement was maintained up to 12 T, confirming the efficacy of Gd addition for the enhancement of transport properties of YBCO film.

Background: Prior studies have proven the safety and efficacy of transcatheter aortic valve implantation (TAVI) in patients with reduced left ventricular (LV) function. This study’s aim was to investigate periprocedural inflammatory responses after TAVI. Methods: Patients with severe symptomatic aortic stenosis and reduced LV function who underwent transfemoral TAVI were enrolled. A paired-matched analysis (1:2 ratio) was performed using patients with preserved LV function. Whole white blood cells (WBC) and subpopulation dynamics as well as the neutrophil to lymphocyte ratio (NLR) were evaluated at different times. Results: A total of 156 patients were enrolled, including 52 patients with LVEF &lt, 40% 35.00 [30.00, 39.25] and 104 with LVEF &gt, 50% 55.00 [53.75, 60.0], p &lt, 0.001. Baseline NLR in the reduced LV function group was significantly higher compared to the preserved LV function group, 2.85 [2.07, 4.78] vs. 3.90 [2.67, 5.26], p &lt, 0.04. After a six-month follow-up, the inflammatory profile was found to be similar in the two groups, NLR 2.94 [2.01, 388] vs. 3.30 [2.06, 5.35], p = 0.288. No significant mortality differences between the two groups were observed in the long-term outcome. Conclusions: TAVI for severe symptomatic aortic stenosis, with reduced LV function, was associated with an improvement in the inflammatory profile that may account for some of the observable benefits of the procedure in this subset of patients.

During Science Verification of the new SEPIA660 facility receiver at APEX, we carried out a shallow line survey of the archetypal Kleinmann-Low Nebula in the Orion star forming region (Orion-KL). These observations cover the tuning range towards the band edges, which has recently been extended beyond ALMA Band 9 specifications. At these frequencies, atmospheric transmission is very low but still sufficient to detect bright lines in Orion-KL. We present the collected spectra and compare with surveys from the literature, demonstrating the capabilities of the instrument., Published in The Messenger vol. 176, pp. 20-24, June 2019.