Publications by authors named "Raabe G"

Background: The diagnostic accuracy of colon capsule endoscopy (CCE) depends on a well-cleansed bowel. Evaluating the cleansing quality can be difficult with a substantial interobserver variation.

Objectives: Our primary aim was to establish a standard of agreement for bowel cleansing in CCE based on evaluations by expert readers.

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The controlled synthesis of nanoparticles with tailored shapes and morphologies has garnered significant attention, driven by the ever-growing demand for advanced materials with defined properties. In nanoparticle formation, various parameters influence the final product, and among these, the solvent plays a pivotal role, as it constitutes the major component of the reaction medium. In this work, the critical role of solvents in controlling the growth of zinc oxide (ZnO) nanoparticles was investigated, with a focus on simple primary alcoholic solvents as the reaction medium.

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The SAMPL9 blind challenge aims to predict the toluene/water partition coefficient of 16 active pharmaceutical ingredients. In this work, the transfer free energy between the solvation in water and toluene is predicted by molecular dynamics simulations using the MBAR method [M. R.

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This study explores the potential of robust, strongly basic type I ion exchange resins-specifically, Amberlyst A26 OH and Lewatit K 6465-as catalysts for the aldol condensation of citral and acetone, yielding pseudoionone. Emphasis is placed on their long-term stability and commendable performance in continuous operational settings. The aldol reaction, which traditionally is carried out using aqueous sodium hydroxide as the catalyst, holds the potential for enhanced sustainability and reduced waste production through the use of basic ion exchange resins in heterogeneous catalysis.

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To reduce the climate impact of thermal engines such as heat pumps or refrigeration machines, refrigerants with a low global warming potential need to be paired with fitting lubricants. As the contamination of those liquid components influences the efficiency and lifetime of these machines, knowledge about their solubility behavior is of great interest. Molecular simulations offer mighty tools to investigate these solubilities while giving structural insight into the systems.

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Electrocatalytic hydrogenation of furfural on metal surfaces has become an important research subject due to the potential of the reaction product 2-methylfuran as a renewable energy resource. Identifying effective determinants in this reaction process requires a thorough investigation of the complex electrode-electrolyte interactions, which considers a variety of the influential components. In this work, in operando electrochemical Raman Spectroscopy and Molecular Dynamics simulations were utilized to investigate different characteristics of the interface layer in the electrocatalytic hydrogenation of furfural.

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A 46-year-old male referred to the Emergency Department with pain in the left flank. The patient suffered from Crohn's disease. He had not experienced any fever, and a urine strip showed signs of blood.

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Unlabelled: Access to clinically recommended applied behavior analysis (ABA) services has been significantly impacted for many consumers in light of the global COVID-19 pandemic. Local shelter-in-place orders and safety concerns have resulted in a movement toward telepractice models across educational and medically necessary ABA services, including at the level of the behavior technician. With this novel mode of technician-level intervention, practitioners have faced many learner, caregiver, and setting variables that have served as barriers to accessing telepractice intervention.

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Despite the high advances of classical molecular simulation to study bulk phases, classical force fields (FFs) to describe interactions at interfaces are rarely available in the literature. In this study, FFs to describe fluid | solid interfaces are developed by matching forces and energies from ab initio simulation and by using a newly developed genetic algorithm (GA). The interfacial FFs are parameterized to be combined with existing classical bulk FFs.

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The COVID-19 pandemic has significantly impacted the everyday lives of many individuals across the globe. The school closures across the majority of the United States have presented administrators, educators, and behavior analysts with the unprecedented task of deciding how best to teach and support our students, especially those accessing special education services. The current article describes the steps our program took, in light of school closures, to advocate for and ultimately create and implement a model that allows special education students to access the behavior-analytic educational supports they had received on campus (e.

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Rational drug design featuring explicit solubility considerations can greatly benefit from molecular dynamics simulations, as they allow for the prediction of the Gibbs free energy of solvation and thus relative solubilities. In our previous work (A. Mecklenfeld, G.

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Accurate solvation free energy ΔG predictions require well parametrized force fields. In order to refit Lennard-Jones (LJ) parameters for improved ΔG predictions for a variety of compound classes and chemical environments, a large number of ΔG calculations is required. As the calculation of ΔG is computational expensive, there is need for efficient but precise calculation methods.

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The dissociation of hierarchically formed dimeric triple lithium bridged triscatecholate titanium(IV) helicates with hydrocarbyl esters as side groups is systematically investigated in DMSO. Primary alkyl, alkenyl, alkynyl as well as benzyl esters are studied in order to minimize steric effects close to the helicate core. The H NMR dimerization constants for the monomer-dimer equilibrium show some solvent dependent influence of the side chains on the dimer stability.

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In this Data in Brief article, we present predictive data for the vapor-liquid equilibria of the binary mixtures of HFO-1123 with R-32, HFO-1234yf, HFO-1234ze(E), R-134a and CO from molecular simulation. The VLE in the binary mixtures are then modeled by the PCP-SAFT equation of state. Therefore we determined PCP-SAFT parameters for the pure HFO compounds as well as binary interaction parameters for all mixtures.

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In this article, the cross-coupling reaction (CCR) of exocyclic, axially chiral, and acyclic alkenyl (N-methyl)sulfoximines with alkyl- and arylzincs is described The CCR generally requires dual Ni catalysis and MgBr promotion, which is effective in diethyl ether but not in THF. NMR spectroscopy revealed a complexation of alkenyl sulfoximines by MgBr in diethyl ether, which suggests an acceleration of the oxidative addition through nucleofugal activation. The CCR of alkenyl sulfoximines generally proceeds in the presence of Ni(dppp)Cl as a precatalyst and MgBr with alkyl- and arylzincs with a high degree of stereoretention at the C and the S atom.

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An enantio- and regioselective allylic alkylation of sulfoximines with Morita-Baylis-Hillman carbonates was developed. The asymmetric reaction is directed by a quinidine-derived organocatalyst providing a range of optically active α-methylene β-sulfoximidoyl esters in high yields (up to 93%) with good to excellent enantiomeric excesses (up to 95%) under mild reaction conditions.

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The control of structural transformations triggered by external signals is important for the development of novel functional devices. In the present study, it is demonstrated that helicates can be designed to structurally respond to the presence of different counterions and to adopt either a compressed or an expanded structure. Reversible switching is not only possible between those two states, furthermore, the twist of the aggregate also can be controlled.

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The calculation of solvation free energies ΔG by molecular simulations is of great interest as they are linked to other physical properties such as relative solubility, partition coefficient, and activity coefficient. However, shortcomings in molecular models can lead to ΔG deviations from experimental data. Various studies have demonstrated the impact of partial charges on free energy results.

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A Cp*Rh(III) complex has been used as catalyst for the preparation of unprecedented 1,2-benzothiazepine 1-oxides by [4 + 3] cyclization of NH-sulfoximines with α,β-unsaturated ketones. For a wide range of substrates with various functional groups, moderate to good product yields were obtained.

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The enantioselective oxidative N-heterocyclic carbene-catalyzed [4+2] annulation reaction of β-methyl enals and cyclic trifluoromethyl ketimines has been developed. A series of biologically interesting dihydroquinazolinone derivatives bearing a trifluoromethyl group and a tetrasubstituted stereocenter are efficiently prepared with very good yields and excellent stereoselectivities.

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tBuCH=C(Li)S(O)(NSO Tol)Ph⋅L (L=2THF, TMEDA) (1⋅L) in THF solution is a monomer with a C-Li bond according to NMR spectroscopy and cryoscopy. It was identified as CIP through the scalar C, Li coupling and Li,{ H} NOE experiments. The CIP has a six-membered C-Li-O-S-N-S chelate ring structure.

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Thermodynamic properties are often modeled by classical force fields which describe the interactions on the atomistic scale. Molecular simulations are used for retrieving thermodynamic data from such models, and many simulation techniques and computer codes are available for that purpose. In the present round robin study, the following fundamental question is addressed: Will different user groups working with different simulation codes obtain coinciding results within the statistical uncertainty of their data? A set of 24 simple simulation tasks is defined and solved by five user groups working with eight molecular simulation codes: DL_POLY, GROMACS, IMC, LAMMPS, ms2, NAMD, Tinker, and TOWHEE.

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Well-defined hypervalent iodine(III) reagents incorporating transferable sulfoximidoyl groups were obtained through ligand exchange reactions of methoxy(tosyloxy)iodobenzene (MTIB) with NH sulfoximines in good to excellent yields. The solid-state structure of a representative product was characterized by X-ray crystallography. Utilizing these reagents in synthesis provides a new, transition-metal-free approach towards N-alkynylated sulfoximines.

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The ability of multiple CF3 -substituted arenes to act as acceptors for anions is investigated. The results of quantum-chemical calculations show that a high degree of trifluoromethyl substitution at the aromatic ring results in a positive quadrupole moment. However, depending on the polarizability of the anion and on the substitution at the arene, three different modes of interaction, namely Meisenheimer complex, side-on hydrogen bonding, or anion-π interaction, can occur.

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A novel one-pot, three-component diastereo- and enantioselective synthesis of spiropyrazolones has been developed involving the aldol condensation of an enal to generate α,β-unsaturated pyrazolones, which react with a second equivalent of enal through an N-heterocyclic carbene (NHC)-catalyzed [3+2] annulation. The desired spirocyclopentane pyrazolones are obtained in moderate to good yields and good to excellent stereoselectivities. Alternatively, starting from cyclic 1,3-diketones, 2,5-chromenediones are available through [2+4] annulation.

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