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We propose and implement an open-source computational workflow, suitable for explorative studies of perovskites. We validate said workflow on a set of lanthanide manganites, and apply it to study the defect-induced phase transition in LaMnO3.

Background Endoscopic vacuum therapy (EVT) is an effective treatment option for leakage of the upper gastrointestinal (UGI) tract. The aim of this study was to evaluate the clinical impact of quality improvements in EVT management on patients’ outcome. Methods All patients treated by EVT at our center during 2012–2021 were divided into two consecutive and equal-sized cohorts (period 1 vs. period 2). Over time several quality improvement strategies were implemented including the earlier diagnosis and EVT treatment and technical optimization of endoscopy. The primary endpoint was defined as the composite score MTL30 (mortality, transfer, length-of-stay > 30 days). Secondary endpoints included EVT efficacy, complications, in-hospital mortality, length-of-stay (LOS) and nutrition status at discharge. Results A total of 156 patients were analyzed. During the latter period the primary endpoint MTL30 decreased from 60.8 to 39.0% (P = .006). EVT efficacy increased from 80 to 91% (P = .049). Further, the need for additional procedures for leakage management decreased from 49.9 to 29.9% (P = .013) and reoperations became less frequent (38.0% vs.15.6%; P = .001). The duration of leakage therapy and LOS were shortened from 25 to 14 days (P = .003) and 38 days to 25 days (P = .006), respectively. Morbidity (as determined by the comprehensive complication index) decreased from 54.6 to 46.5 (P = .034). More patients could be discharged on oral nutrition (70.9% vs. 84.4%, P = .043). Conclusions Our experience confirms the efficacy of EVT for the successful management of UGI leakage. Our quality improvement analysis demonstrates significant changes in EVT management resulting in accelerated recovery, fewer complications and improved functional outcome.

Robust computational workflows are important for explorative computational studies, especially for cases where detailed knowledge of the system structure or other properties is not available. In this work, we propose a computational protocol for appropriate method selection in density functional theory, based strictly on open source software. The protocol is applicable to perovskite systems and does not require a starting crystal structure. We validate this protocol using a set of crystal structures of lanthanide manganates, confirming that PBE+U is a reasonable choice for this purpose, along with the OLYP and HCTH120 density functional approximations. We also highlight that +U values derived from linear response theory are robust and their use leads to improved results. We investigate whether the performance of methods for predicting the bond length of related gas phase diatomics correlates with their performance for bulk structures, showing that care is required when interpreting benchmark results. Finally, using defective LaMnO3 as a case study, we investigate whether the three selected methods can computationally reproduce the experimentally determined fraction of MnIV+ at which the orthorhombic to rhombohedral phase transition occurs. The results are mixed, with HCTH120 providing a good quantitative agreement, while PBE+U better capturing the qualitative aspects of this phase transition.

Automation of experiments is a key component on the path of digitalization in catalysis and related sciences.

Die Buchbranche in herausfordernden Zeiten: Interview mit Peter Kraus vom Cleff, Hauptgeschäftsführer des Börsenvereins des Deutschen Buchhandels

Community efforts in the computational molecular sciences (CMS) are evolving toward modular, open, and interoperable interfaces that work with existing community codes to provide more functionality and composability than could be achieved with a single program. The Quantum Chemistry Common Driver and Databases (QCDB) project provides such capability through an application programming interface (API) that facilitates interoperability across multiple quantum chemistry software packages. In tandem with the Molecular Sciences Software Institute and their Quantum Chemistry Archive ecosystem, the unique functionalities of several CMS programs are integrated, including CFOUR, GAMESS, NWChem, OpenMM, Psi4, Qcore, TeraChem, and Turbomole, to provide common computational functions, i.e., energy, gradient, and Hessian computations as well as molecular properties such as atomic charges and vibrational frequency analysis. Both standard users and power users benefit from adopting these APIs as they lower the language barrier of input styles and enable a standard layout of variables and data. These designs allow end-to-end interoperable programming of complex computations and provide best practices options by default.

International audience; In Peierls-distorted materials, photoexcitation leads to a strongly coupled transient response between structural and electronic degrees of freedom, always measured independently of each other. Here we use transient reflectivity in the extreme ultraviolet to quantify both responses in photoexcited bismuth in a single measurement. With the help of first-principles calculations based on density-functional theory (DFT) and time-dependent DFT, the real-space atomic motion and the temperature of both electrons and holes as a function of time are captured simultaneously, retrieving an anticorrelation between the A$_{1g}$ phonon dynamics and carrier temperature. The results reveal a coherent, bidirectional energy exchange between carriers and phonons, which is a dynamical counterpart of the static Peierls-Jones distortion, providing validation of previous theoretical predictions.

Extrapolation of density functional theory results from 2- and 3-ζ calculations is a promising method for extracting higher accuracy data from calculations of systems at the affordability limit. In this work, the author presents formulas for the determination of extrapolation parameters, which account for the makeup of the density functional approximation. The formulas are fitted to reproduce the complete basis set limit energies of PBE and related density functional approximations, using a set of 30 singlet diatomics. Their performance is extensively evaluated using standard benchmark data sets. The current systematically derived expressions are shown to be transferrable outside the PBE family of functional approximations, with the resulting extrapolation parameters outperforming the previous, less-systematic values. A good performance of [2,3]-ζ extrapolations for interaction energies of systems with significant noncovalent character is confirmed and holds even in systems of ∼100 atoms in size.

An accurate semi-experimental equilibrium structure of 8-hydroxyquinoline (8-HQ) has been determined combining experiment and theory. The cm-wave rotational spectrum of 8-HQ was recorded in a pulsed supersonic jet using broadband dual-path reflection and narrowband Fabry-Perot-type resonator Fourier-transform microwave spectrometers. Accurate rotational and quartic centrifugal distortion constants and 14 N quadrupole coupling constants are determined. Rotational constants of all 13 C, 18 O and 15 N singly substituted isotopologues in natural abundance and those of a chemically synthesized OD isotopologue were used to obtain geometric parameters for all the heavy atoms and the hydroxyl hydrogen from a number of structure determination models. Theoretical approaches allowed for the determination of a semi-experimental equilibrium structure, reSE in which computed rovibrational and electronic corrections were utilized to convert vibrational ground state constants into equilibrium constants. Despite the molecule having only a horizontal plane of symmetry and possessing 11 individual heavy atoms, microwave spectroscopy has allowed for a reliable and accurate structure determination. A mass dependent, rm2 structure was determined and proved to be equally reliable by comparison with the B3LYP-D3(BJ)/aVTZ equilibrium structure.

Boron nitride and related boron-containing materials have recently been suggested as very promising catalysts in the oxidative dehydrogenation of propane. The high selectivity toward propylene at comparably high conversion significantly exceeds the performance of established vanadium-based catalysts. In the current work we show that the high selectivity toward propylene and ethylene is fully consistent with a gas-phase conversion mechanism and that it can be modeled reasonably well by the recent detailed microkinetic reaction mechanism of Hashemi and co-workers [ Proc. Combust. Inst. 2019, 37, 461]. Our analysis, using six heterogeneous catalytic reaction pathways, each representing a hypothetical limit case, shows that the boron nitride catalyst is responsible for initiating the gas-phase chemistry. The increased conversion of propane in cases with water cofeed, as well as the trends in the selectivities of minor species upon dilution of the catalytic bed and upon varying the C3H8/O2 inlet ratio, as observed by Venegas and Hermans [ Org. Process Res. Dev. 2018, 22, 1644], are here explained as gas-phase phenomena. Hence, the oxidative dehydrogenation of propane over boron nitride catalysts is an example of a coupled gas and catalytic chemistry system. The current work also highlights the importance of modeling of the complete heated zone, including the rear heat shields and reactor padding if present.

Abstract The performance in heterogeneous catalysis is an example of a complex materials function, governed by an intricate interplay of several processes (e.g., the different surface chemical reactions, and the dynamic restructuring of the catalyst material at reaction conditions). Modeling the full catalytic progression via first-principles statistical mechanics is impractical, if not impossible. Instead, we show here how a tailored artificial-intelligence approach can be applied, even to a small number of materials, to model catalysis and determine the key descriptive parameters (“materials genes”) reflecting the processes that trigger, facilitate, or hinder catalyst performance. We start from a consistent experimental set of “clean data,” containing nine vanadium-based oxidation catalysts. These materials were synthesized, fully characterized, and tested according to standardized protocols. By applying the symbolic-regression SISSO approach, we identify correlations between the few most relevant materials properties and their reactivity. This approach highlights the underlying physicochemical processes, and accelerates catalyst design. Impact statement Artificial intelligence (AI) accepts that there are relationships or correlations that cannot be expressed in terms of a closed mathematical form or an easy-to-do numerical simulation. For the function of materials, for example, catalysis, AI may well capture the behavior better than the theory of the past. However, currently the flexibility of AI comes together with a lack of interpretability, and AI can only predict aspects that were included in the training. The approach proposed and demonstrated in this IMPACT article is interpretable. It combines detailed experimental data (called "clean data") and symbolic regression for the identification of the key descriptive parameters (called "materials genes") that are correlated with the materials function. The approach demonstrated here for the catalytic oxidation of propane will accelerate the discovery of improved or novel materials while also enhancing physical understanding.

We investigate the role of gas-phase phenomena in the heterogeneous oxidative dehydrogenation of propane over hexagonal boron nitride. We apply a recently developed gas-phase combustion model for low-temperature combustion of propane and couple it with several surface microkinetic mechanisms to probe the selectivity limits using the open-source flame solver Cantera. We show that while the conversion of propane is surface-driven, the selectivities are significantly influenced by the gas-phase, especially when dilute catalyst beds are used.

The “Seven Pillars” of oxidation catalysis proposed by Robert K. Grasselli represent an early example of phenomenological descriptors in the field of heterogeneous catalysis. Major advances in the theoretical description of catalytic reactions have been achieved in recent years and new catalysts are predicted today by using computational methods. To tackle the immense complexity of high-performance systems in reactions where selectivity is a major issue, analysis of scientific data by artificial intelligence and data science provides new opportunities for achieving improved understanding. Modern data analytics require data of highest quality and sufficient diversity. Existing data, however, frequently do not comply with these constraints. Therefore, new concepts of data generation and management are needed. Herein we present a basic approach in defining best practice procedures of measuring consistent data sets in heterogeneous catalysis using “handbooks”. Selective oxidation of short-chain alkanes over mixed metal oxide catalysts was selected as an example.

Basis set extrapolation is a common technique in wavefunction theory used to squeeze better performance out of the highest affordable level of theory by combining it with lower quality calculations. In this work, I present analogous techniques for basis set extrapolation in density functional theory, focusing on [2,3]-ζ calculations and including double hybrid and dispersion-corrected functionals. My recommendations are based on basis set limit data from finite element calculations and estimates of basis set limits for double hybrid corrections, and they are validated using the GMTKN55 and NCDT datasets. A short review of extrapolation methods for Hartree-Fock calculations based on modern finite element data is carried out to inform this work. Extrapolation of [2,3]-ζ calculations in def2-Xzvpd and cc-pvXz-pp basis sets with the proposed recipes routinely matches and sometimes outperforms 4-ζ calculations at a fraction of the cost. The methods are implemented in Psi4, allowing for an automated and intuitive application.

Psi4 is a free and open-source ab initio electronic structure program providing Hartree–Fock, density functional theory, many-body perturbation theory, configuration interaction, density cumulant theory, symmetry-adapted perturbation theory, and coupled-cluster theory. Most of the methods are quite efficient thanks to density fitting and multi-core parallelism. The program is a hybrid of C++ and Python, and calculations may be run with very simple text files or using the Python API, facilitating post-processing and complex workflows; method developers also have access to most of Psi4’s core functionality via Python. Job specification may be passed using The Molecular Sciences Software Institute (MolSSI) QCSchema data format, facilitating interoperability. A rewrite of our top-level computation driver, and concomitant adoption of the MolSSI QCArchive Infrastructure project, make the latest version of Psi4 well suited to distributed computation of large numbers of independent tasks. The project has fostered the development of independent software components that may be reused in other quantum chemistry programs.

We report a benchmark-quality equilibrium-like structure of the Xe⋯OCS complex, obtained from microwave spectroscopy. The experiments are supported by a wide array of highly accurate calculations, expanding the analysis to the complexes of He, Ne, Ar, Kr, Xe, and Hg with OCS. We investigate the trends in the structures and binding energies of the complexes. The assumption that the structure of the monomers does not change significantly upon forming a weakly bound complex is also tested. An attempt at reproducing the r(2)m structure of the Xe⋯OCS complex with correlated wavefunction theory is made, highlighting the importance of relativistic effects, large basis sets, and inclusion of diffuse functions in extrapolation recipes.

Due to their scalability and global abundance of sunlight, photovoltaic panels are a promising option as a renewable energy source. Implementation of photovoltaic technologies on a large scale requires a careful business-case assessment, aimed at the selection of the technological option most appropriate for the local conditions in terms of long-term performance. For this purpose, five types of modules representative of current options on the market were tested under field conditions for five years at a test facility in Germany. The degradation rates of module performance were computed from the obtained photovoltaic power normalized by both recorded and modeled solar irradiance. The results emphasize the relevance of using modeled irradiance data in addition to recorded solar irradiance in order to extract reliable degradation rates. The available methodological tools still have to be adapted to every dataset for the most accurate result. Eventually, robust degradation rates were extracted from experimental power data, based on modeled clear-sky irradiance, and a combination of aggregation and regression strategies. The results show distinctive degradation behaviors of the five available commercial photovoltaic modules in response to the local conditions.

Among noble metal catalysts, rhodium (Rh) is unique in its ability to perform a one-step synthesis of ethanol from syngas. The first steps following the adsorption of syngas on Rh surfaces are assumed to be responsible for the conversion of CO and the selectivity effects between C1 , C2 , and oxygenated species. In the current work, constrained ab initio molecular dynamics are applied to investigate the kinetics of CO dissociation and hydrogenation over flat and stepped Rh surfaces. The obtained barriers for the Rh(111) surface are in good agreement with the literature data. On the stepped Rh(211) surface, a large site-dependent variation in barrier height is shown, with the upper terrace exhibiting behavior comparable to the Rh(111) surface, whereas the barriers over the lower terrace site are generally significantly lower. The rate constants are calculated using transition state theory for both surfaces, and are applied successfully in a microkinetic model, confirming the predicted impact on CO conversion and CH4 /C1 -oxygenate/C2 Hn selectivity. In addition to the high-accuracy energetics and rate constants reported for CO dissociation/hydrogenation and the presentation of an updated microkinetic mechanism for Rh catalysts, the applicability of constrained molecular dynamics for reaction barrier calculation is confirmed, and sensitive pathways affecting the selectivity between formaldehyde/methanol over Rh catalysts are highlighted.

Accurate data sets including noncovalent interactions have become essential for benchmarking computational methods. However, while there is much focus on obtaining an accurate description of relative energies, reliable prediction of accurate equilibrium geometries is also important. To facilitate the benchmarking of computed geometries, the current work includes an accurate data set of semiexperimental equilibrium geometries of noncovalent complexes that can be directly compared to ab initio data. The structures are based on high-accuracy spectroscopic data, combined with vibrational corrections at the double-hybrid density functional level. The current work is designed to complement available data sets of semiexperimental geometries of small rigid molecules and ab initio geometries of complexes. The benchmark-quality data comprises 16 complexes and includes dispersion interactions, hydrogen bonding, CH/π···π interactions, and trimers. In addition to the reference data, accurate counterpoise-corrected geometries have been obtained up to the CCSD level, along with interaction energies. A short overview of the performance of computational methods, including dispersion-corrected B3LYP and B2PLYP functionals, is also included.

A reaction class-based framework for the development of heterogeneous mechanisms is applied to study the (partial) oxidation of ethane over platinum. The rate parameters for the surface chemistry were derived using a systematic application of variational transition state theory (VTST) for adsorption, desorption, and Eley–Rideal reactions coupled with two-dimensional (2D) collision theory for reactions occurring on the surface. The approach removes the need for the experimental determination of surface sticking coefficients and the associated major uncertainties. The barrier heights were determined using the unity bond index–quadratic exponential potential (UBI–QEP) method. The combined gas- and surface-phase chemistry was evaluated against independent data sets obtained from three experimental configurations. The associated 18 cases cover a wide range of residence times, stoichiometries (0.1 < ϕ < 10.4), and inlet pressures (1–12 bar). The work highlights the generality of the VTST approach that is shown to outperform the customary sticking coefficient-based methods for key aspects. A sensitivity analysis highlights the importance of the O2 and CO adsorption pathways.

Please see the abstract within the article.

The polarized interface between two immiscible liquids plays a central role in many technological processes. In particular, for electroanalytical and ion extraction applications, an external electric field is typically used to selectively induce the transfer of ionic species across the interfaces. Given that it is experimentally challenging to obtain an atomistic insight into the ion transfer process and the structure of liquid-liquid interfaces, atomistic simulations have often been used to fill this knowledge gap. However, due to the long-range nature of the electrostatic interactions and the use of 3D periodic boundary conditions, the use of external electric fields in molecular dynamics simulations requires special care. Here, we show how the simulation setup affects the dielectric response of the materials and demonstrate how by a careful design of the system it is possible to obtain the correct electric field on both sides of a liquid-liquid interface when using standard 3D Ewald summation methods. In order to prove the robustness of our approach, we ran extensive molecular dynamics simulations with a rigid-ion and polarizable force field of the water/1,2-dichloroethane interface in the presence of weak external electric fields.

In this work, we compare the results obtained with 89 computational methods for predicting noncovalent bond lengths in weakly bound complexes. Evaluations for the performance in noncovalent interaction energies and covalent bond lengths obtained from five other data sets are included. The overall best performing density functional is the ωB97M-V method, achieving balanced results across all three categories. For noncovalent geometries, the best methods include B97M-V, B3LYP-D3(BJ) and DSD-PBEPBE-D3(BJ). The effects of systematic improvement of the density functional approximation and of dispersion corrections are also discussed.

open 12 si MIUR “PRIN 2015” funds (Grant Number 2015F59J3R) By combining rotational spectroscopy in supersonic expansion with the capability of state-of-the-art quantum-chemical computations in accurately determining structural and energetic properties, the genuine nature of a sulfur–sulfur chalcogen bond between dimethyl sulfide and sulfur dioxide has been unveiled in a gas-jet environment free from collision, solvent and matrix perturbations. A SAPT analysis pointed out that electrostatic S⋅⋅⋅S interactions play the dominant role in determining the stability of the complex, largely overcoming dispersion and C−H⋅⋅⋅O hydrogen-bond contributions. Indeed, in agreement with the analysis of the quadrupole-coupling constants and of the methyl internal rotation barrier, the NBO and NOCV/CD approaches show a marked charge transfer between the sulfur atoms. Based on the assignment of the rotational spectra for 7 isotopologues, an accurate semi-experimental equilibrium structure for the heavy-atom backbone of the molecular complex has been determined, which is characterized by a S⋅⋅⋅S distance (2.947(3) Å) well below the sum of van der Waals radii. embargoed_20191010 Obenchain, Daniel A.; Spada, Lorenzo; Alessandrini, Silvia; Rampino, Sergio; Herbers, Sven; Tasinato, Nicola; Mendolicchio, Marco; Kraus, Peter; Gauss, Jürgen; Puzzarini, Cristina; Grabow, Jens-Uwe*; Barone, Vincenzo Obenchain, Daniel A.; Spada, Lorenzo; Alessandrini, Silvia; Rampino, Sergio; Herbers, Sven; Tasinato, Nicola; Mendolicchio, Marco; Kraus, Peter; Gauss, Jürgen; Puzzarini, Cristina; Grabow, Jens-Uwe*; Barone, Vincenzo

A bundled waveguide approach is introduced for multi-beam satellite applications providing remarkable mass reductions compared with standard single waveguide interconnections. Several waveguide paths are associated closely in a profile sharing common separation walls. Novel waveguide components (e.g. bends, transformers, etc.) have been developed, to allow convenient combination of bundled waveguide sections (with and without flange interconnections) for the realization of arbitrarily routed (bundled) waveguide runs with optimal interfacing at the antenna and payload subsystems. The use of cigar-shape waveguide cross sections for the bundled profiles yield low insertion loss and improved manufacturing properties. The realization of first bundled waveguide runs at 20GHz prove the applicability and advantages of the approach.

Background A ‘third hand’ is useful for holding the endoscope during surgery. The SOLOASSIST camera holder (AktorMed GmbH, Germany), which is used for abdominal surgery, is supposed to be modified for head and neck surgery. The aim of this study was to determine the intraoperative hand-held endoscopic range of motion for different surgical procedures and to define the required technical changes. Methods The intraoperative movements of the hand-held endoscope during sinus surgery, rigid laryngoscopy, and lateral skull base surgery were measured and calculated. Results The endoscopic range of motion during surgery revealed diverse geometric bodies and volumes. For use in the ENT area, the system must be expanded by a manual release function for the driven axes and two additional lockable axes at the distal end of the arm. Conclusion Intraoperative endoscopic range of motions in head and neck surgery are highly specific and, as expected, differ from the endoscopic movements in abdominal surgery. Copyright © 2015 John Wiley & Sons, Ltd.

A novel re-configuration approach for high-Q cavity filters is shown to provide re-allocation of center frequency and bandwidth with only two actuations drives. It relies on a side-wall cavity arrangement that allows independent movement of the cavity end-walls at both sides; i.e. all cavity end-walls at each side are associated with one remote-controlled drive unit for a synchronous adjustment. Thus, the lengths of the cavities and the electro-magnetic (EM) field strength at the coupling discontinuities can be varied to accommodate flexible center frequency and bandwidth re-allocations. This basic principle has been considered for the implementation of 2- and 5-order filters at 11.2GHz using TE113 dual-mode cavities. The designs have been focused to satisfy the same demands imposed on comparable fixed filters, namely the realization of responses with convenient located transmission zeros (TZ) and the same high unloaded Q for all reallocations. The special design considerations for this reconfigurable filter development are introduced. The results of the EM-analysis of the 5-order filter and the measured remote controlled hardware of the 2-order design prove the feasibility of remote controlled center frequency and bandwidth reallocation with only two actuation drives.

A systematic approach for the development of heterogeneous mechanisms is applied and evaluated for the catalytic partial oxidation of methane over platinum (Pt) and rhodium (Rh). The derived mechanisms are self-consistent and based on a reaction class-based framework comprising variational transition state theory (VTST) and two-dimensional collision theory for the calculation of pre-exponential factors with barrier heights obtained using the unity bond index–quadratic exponential potential (UBI–QEP) method. The surface chemistry is combined with a detailed chemistry for the gas phase, and the accuracy of the approach is evaluated over Pt for a wide range of stoichiometries (0.3 ≤ ϕ ≤ 4.0), pressures (2 ≤ P (bar) ≤ 16), and residence times. It is shown that the derived mechanism can reproduce experimental data with an accuracy comparable to that of the prevalent collision theory approach and without the reliance on experimental data for sticking coefficients. The derived mechanism for Rh shows encouraging agreement for a similar set of conditions, and the robustness of the approach is further evaluated by incorporating partial updates via more accurate DFT-determined barrier heights. Substantial differences are noted for some channels (e.g., where reaction progress is strongly influenced by early transition states) though the impact on the overall agreement with experimental data is moderate for the current systems. Remaining discrepancies are explored using sensitivity analyses to establish key parameters. The study suggests that the overall framework is well-suited for the efficient generation of heterogeneous reaction mechanisms, that it can serve to identify key parameters where high accuracy ab initio methods are required, and that it permits the inclusion of such updates as part of a gradual refinement process.

Endoscope holders are utilized by a variety of surgeons but are not commonplace in head and neck surgery. The SOLOASSIST active camera holder, which is currently used for abdominal surgery, will soon be adapted for head and neck surgery in collaboration with AKTORmed GmbH SOLO SURGERY (Barbing, Germany). In our pre-feasibility study, we analyzed the use of the existing endoscope holder on anatomical specimens during head and neck surgery. Based on these results, we are proceeding towards the development of a new endoscope holder for head and neck surgery. First, we drafted the technical concepts and discussed the advantages and disadvantages of the system. Then, we used anatomic specimens to measure the forces that occur intraoperatively during sinus surgery. Next, we designed a computer-aided design (CAD) model. Finally, we developed the first production prototype and used it for a frontal skull base procedure on an anatomical specimen. We present the three most promising concepts for a new holder. The resulting total force (F res = √(X (2) + Y (2) + Z (2))) was calculated to be 3.2 N during sinus surgery. We could observe all necessary intraoperative landmarks with the endoscope and its holder in a sinus and frontal skull base surgery. We developed a production prototype of a new endoscope holder and demonstrate satisfactory results in the use of anatomic specimens for skull base surgery.

A unique high Q dual-mode cavity filter design for remote controlled reallocation of center frequency and bandwidth is introduced. It builds on a sidewall arrangement of cylindrical cavities that allows independent movement of the end-walls at both sides. The dual mode cavities are coupled as doublets for the realization of transmission zeros. All cavity end-walls situated at the same side are synchronously adjusted, i.e., the reconfiguration of the overall filter requires only two actuation drives1. This solution has been validated by 2-order and 5-order filter designs implemented with TE 113 dual-mode cavities at 11.2GHz. The results of the EM-analysis of the 5-order filter and the measured remote controlled hardware of the 2-order design demonstrate the capability of center frequency and bandwidth reallocation.

A novel reconfigurable (de-)multiplexer DEMUX solution is introduced that allows flexible re-allocation of bandwidths and center frequencies of the associated high-Q cavity channel filters. The filters are interconnected with a manifold. For the reconfiguration of the responses, a synchronous movement of the cavity end-walls of each filter is considered. This is the final implementation of the DEMUX requires only two actuation drives per filter for the re-allocation of bandwidths and center frequencies. The solution has been proven by an elementary 2-channel DEMUX configuration with 4-order filters using TM 120 mode cavity types. The results of the overall DEMUX design demonstrate the feasibility of this new general approach.

The rotational constants of s-trans and s-cis methyl methacrylate and methacrylic acid are determined from microwave spectra. All singly substituted heavy-atom isotopologs of the four species are measured in natural abundance. The experimental rotational constants are combined with anharmonic vibrational corrections using the Coulomb-attenuating method, Becke, three-parameter, Lee-Yang-Parr density functional with Grimme’s D3 dispersion corrections and the Becke-Johnson damping function, yielding precise semi-experimental equilibrium rotational constants. These constants are used to determine semi-experimental equilibrium structures with sub-picometer accuracy, suitable for benchmarking purposes.The rotational constants of s-trans and s-cis methyl methacrylate and methacrylic acid are determined from microwave spectra. All singly substituted heavy-atom isotopologs of the four species are measured in natural abundance. The experimental rotational constants are combined with anharmonic vibrational corrections using the Coulomb-attenuating method, Becke, three-parameter, Lee-Yang-Parr density functional with Grimme’s D3 dispersion corrections and the Becke-Johnson damping function, yielding precise semi-experimental equilibrium rotational constants. These constants are used to determine semi-experimental equilibrium structures with sub-picometer accuracy, suitable for benchmarking purposes.

A systematic and self-consistent approach is applied to study the combustion of hydrogen and syngas over platinum using coupled detailed gas phase and surface reaction mechanisms. The surface chemistry is derived using a reaction class-based framework comprising variational transition state theory (VTST), two-dimensional collision theory and the unity bond index-quadratic exponential potential for barrier heights. The latter approach is augmented by the inclusion of more accurate data, such as the heat of adsorption of CO, and VTST is used to systematically remove the need for the surface sticking coefficients associated with adsorption and desorption processes. Transition-state theory estimates for several reaction classes are produced by combining the M06 family of density functionals with the Stuttgart/Dresden effective core potential for metal atoms. The developed method reproduces experimental data with an accuracy comparable or better than the previously used collision theory approach and without the reliance on experimental parameters. The presented framework is well-suited for the efficient generation of novel heterogeneous reaction mechanisms and also serves to identify key parameters where high accuracy ab initio methods may be required. The latter is exemplified via the sensitivity of selected results to the adsorption of carbon monoxide on platinum.

Mucormycosis are an emerging group of life-threatening fungal infections caused by filamentous fungi of the Mucorales family. Mucormycosis are most common in stem-cell transplant recipients and patients with underlying hematologic malignancies, poorly controlled diabetes mellitus, trauma, neutropenia, corticosteroid and deferoxamine therapy due to deficiency of phagocytic function, elevated serum levels of available iron and host-pathogen interaction. The fungi penetrate blood vessels causing endothelial damage and extensive angioinvasion with infarction, necrosis, and thrombosis of different tissues. Mucormycosis carries a very high mortality in cases of pulmonary disease, with even higher rates when there is difficulty establishing the diagnosis. We present a case of 67-year-old man with pulmonary form of mucormycosis presenting as opportunistic infection post induction chemotherapy for acute myeloid leukemia FAB M2. We treated the patient with intravenous amphotericin B for 4 weeks and endobronchial resection, after which he clinically and radiographically improved. Overall, early consideration of mucormycosis can lead to an earlier diagnosis, medical and surgical therapy, and an increased survival rate. Furthermore, we provide a real example of multiple thinking strategies, needed for a patient oriented clinical practice. Overall, this case is a challenging example between clinical judgment and available validated guidelines.

The microwave spectra of 10 teflic acid isotopologues were recorded in the frequency range of 3-25 GHz using supersonic jet-expansion Fourier transform microwave spectroscopy. Despite being asymmetric in its equilibrium structure, the delocalization of the hydrogen atom leads to a symmetric top vibrational ground state structure. In this work, we present the zero point structure obtained from the experimental rotational constants and an approach to determine the semi-experimental equilibrium structure aided by ab initio data. The Te–O bond length determined in the equilibrium structure is accurate to the picometer and can be used as a benchmark for computational methods treating relativistic effects.