Natural Isotopic Abundance 13C and 15N Multidimensional Solid-State NMR Enabled by Dynamic Nuclear Polarization

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Resolution Enhancement in Multidimensional Solid-State NMR Spectroscopy of Proteins using Spin-State Selection

A new experimental approach is introduced which leads to significant resolution enhancement in multidimensional 13C-13C correlation experiments of microcrystalline systems. Spin-state-selective techniques, adapted for solid-state NMR, are used for removing the J-coupling contribution to the 13C lineshapes. Combination of the spin-state-selective elements and standard ZQ or DQ solid-state NMR mixing sequences allows to perform a spin-state-selective polarization transfer. In addition to the resolution improvement, the new technique enables to distinguish "direct" cross peaks involving covalently bound nuclei from "relayed" cross peaks

The influence of human interaction on guinea pigs: behavioral and thermographic changes during animal-assisted therapy

Guinea pigs are often involved in animal-assisted therapy (AAT) but there is little knowledge about the effects of human contact on guinea pigs involved in AAT. The aim of this study was to investigate effects of availability of a retreat, presence of conspecifics, prior experience with AAT, and human interaction on indicators of welfare in guinea pigs involved in AAT. Guinea pigs of both sexes and different ages (n=20) were assigned to a randomized, controlled within-subject trial with repeated measurements. Each guinea pig was tested in four settings: (I) therapy with retreat possibility with conspecifics, (II) therapy with retreat possibility without conspecifics, (III) therapy without retreat possibility, and (IV) setting without human interaction. We measured changes in eye temperature, as a proxy to infer stress levels, at 5-s intervals with a thermographic camera. All sessions were video recorded and the guinea pigs' behavior was coded using continuous recording and focal animal sampling. For the statistical analysis we used generalized linear mixed models, with therapy setting as a fixed effect and individual guinea pig as a random effect. We observed a temperature increase relative to baseline in settings (I) therapy with retreat with conspecifics present and (III) therapy without retreat. The percentage of time a guinea pig was petted was positively correlated with a rise in the eye temperature independent of the setting. Time spent eating was reduced in all therapy settings (I-III) compared to the setting without HAI (human animal interaction) (IV). In the setting with retreat (I), guinea pigs showed more active behaviors such as locomotive behavior or startling compared to the setting without retreat (III) and the setting without HAI (IV). When no retreat was available (III), they showed more passive behaviors, such as standing still or freezing compared to therapy with retreat (I). Based on our results we identified the behaviors "reduced eating", "increased startle" and "increased freezing" as indicators of an increased stress level. Petting the guinea pigs was correlated with a rise in the eye temperature and might be a factor which can cause stress. Our results support the suggestion that guinea pigs involved in AAT should have a retreat possibility, should have access to conspecifics, and should be given time to adapt to a new setting. In this way, stress might be reduced

A Three-Hybrid Approach to Scanning the Proteome for Targets of Small Molecule Kinase Inhibitors

AbstractIn this study, we explored the application of a yeast three-hybrid (Y3H)-based compound/protein display system to scanning the proteome for targets of kinase inhibitors. Various known cyclin-dependent kinase (CDK) inhibitors, including purine and indenopyrazole analogs, were displayed in the form of methotrexate-based hybrid ligands and deployed in cDNA library or yeast cell array-based screening formats. For all inhibitors, known cell cycle CDKs as well as novel candidate CDK-like and/or CDK-unrelated kinase targets could be identified, many of which were independently confirmed using secondary enzyme assays and affinity chromatography. The Y3H system described here may prove generally useful in the discovery of candidate drug targets

Wege in die Ernährungszukunft der Schweiz - Leitfaden zu den grössten Hebeln und politischen Pfaden für ein nachhaltiges Ernährungssystem

Aus wissenschaftlicher Sicht ist klar: Unser Ernährungssystem ist nicht nachhaltig. Um unsere Lebens- und Wirtschaftsgrundlagen zu erhalten, braucht es eine Neuausrichtung über die gesamte Wertschöpfungskette. Diese ist gleichzeitig ein Schlüssel zur Erreichung der Agenda 2030 für nachhaltige Entwicklung. SDSN Schweiz hat das wissenschaftliche Gremium Ernährungszukunft Schweiz initiiert, um einen Wegweiser zu entwickeln. Er soll es der Schweiz erlauben, Chancen rechtzeitig anzupacken und unkontrollierbare Kostenfolgen zu vermeiden. Das wissenschaftliche Gremium hat international wegweisende Pionierarbeit geleistet. In einem interdisziplinären wissenschaftlichen Prozess wurde zum ersten Mal für ein Land ein umfassender Handlungspfad zur Neuausrichtung des Ernährungssystems im Einklang mit den Zielen für nachhaltige Entwicklung ausgearbeitet. Die beteiligten Forschenden schaffen damit eine wichtige Grundlage für die weitere politische Diskussion in der Schweiz und international

Multi-dimensional magnetic resonance imaging in a stray magnetic field

International audienc

Efficient 2D double-quantum solid-state NMR spectroscopy with large spectral widths

International audience2D double-quantum single-quantum correlation spectra with arbitrary spectral widths can be recorded with SR26 and related supercycled recoupling sequences when applying Supercycle-Timing-Compensation (STiC) phase shifts. This concept widely extends the applicability of supercycled sequences, most importantly for obtaining long-range distance constraints for structure determination with solid-state NMR