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Optimizing selectivity of the Cerebellar Cognitive Affective Syndrome Scale by use of correction formulas, and validation of its German version
No full textUnraveling the relationship between PET surfaces and their hydrolases
No full textPlastics, especially polyethylene terephthalate (PET), are vital in modern life, with global production exceeding 400 million tons annually. This extensive use has led to significant plastic waste pollution, highlighting the need for effective recycling strategies. PET, one of the most recycled plastics, is a prime candidate for degradation into its original monomers through engineered PET hydrolases – enzymes with industrial potential. While previous engineering efforts have mainly focused on enhancing thermostability and catalytic efficiency, the crucial aspect of enzyme adsorption to PET surfaces has received less attention. This review specifically addresses the mechanisms of enzyme adsorption, detailing relevant experimental methods and simulation techniques while emphasizing the potential for engineering more effective PET hydrolases
Long‐Range Cation Disorder Enhances Comprehensive Performance in Mn‐Rich Layered Sodium Cathodes
No full textInvestigation of Dynamic Material Changes During the Preparation of ZnPd Nanoparticles Supported on ZnO and their Catalytic Application in Methanol Steam Reforming onthe Atomic Level
No full textGiven its high energy density and sustainability, hydrogen is regarded as a crucial energy carrier in the pursuit of a carbon-free energy economy. In the search for a storage medium of hydrogen, methanol is emerging as a promising chemical storage. The recovery of hydrogen is achieved through the process of methanol steam reforming, whereby methanol and water are transformed into hydrogen and carbon dioxide. The intermetallic ZnPd nanoparticle supported on ZnO has been demonstrated to function as an excellent catalyst for the reforming, due to its high CO₂ selectivity and activity. However, the favourable catalytic performance is first established during catalysis. The reason for the enhancement of the catalytic properties appears to be a dynamic structural evolution of the catalyst, as evidenced by the formation of ZnO patches. The nanostructural dynamics and the underlying cause of the improved catalytic properties can be elucidated by analysing the synthesis and catalysis of the catalytic system in situ. The comprehensive work studies the preparation, structural evolution, and catalytic application of ZnPd nanoparticles supported on ZnO during methanol steam reforming (MSR), using in situ scanning transmission electron microscopy (STEM). The preparation stages, including calcination of supported palladium nitrate and reduction of palladium oxide, were analysed. In situ calcination revealed that palladium nitrate transforms into palladium oxide at ~170 °C, leading to nanoparticle growth, with a stable size window between 200-400 °C. At temperatures above 460 °C, PdO decomposes into elemental palladium, triggering particle mobility, agglomeration, and ZnO nanorod formation. Further heating above 660 °C under high vacuum caused ZnO faceting and decomposition, which was facilitated by the evaporation of elemental zinc and oxygen. In situ reduction of supported PdO resulted in the formation of intermetallic ZnPd via two distinct formation mechanisms: hydrogen spillover-induced ZnO migration and encapsulation of Pd nanoparticles, followed by ZnPd nucleation and core-shell structure formation. The findings align with those of ex situ experiments and existing literature, confirming that the electron beam enhances the reaction but does not activate it. In situ STEM experiments in open and closed cell configurations demonstrated that methanol acts as a strong reducing agent for ZnO, while hydrogen and water steam stabilise the system. Under MSR conditions, ZnPd nanoparticles are subject to compositional and morphological changes, including Zn enrichment and nanoparticle faceting. The formation of ZnO patches, which was observed for the first time in situ, was found to preferentially occur on ZnPd facets and Znenriched areas. This formation requires a precise balance between hydrogen, water, and methanol and thus is sensitively dependent on the chemical potential. The research provides novel insights into the dynamic behaviour of ZnPd/ZnO catalysts under operational conditions, advancing the methodology for studying catalysts in steam environments and contributing to the broader understanding of catalytic systems
Spherical neutron polarimetry at MAGiC
No full textThe instrument MAGIC at ESS has been designed with an option for longitudinal XYZ polarisation analysis, highly performing in a wavelength band from 2 to 6 Å. A novel extension to the instrument MAGIC will be spherical neutron polarimetry. To date spherical neutron polarimetry has been routinely established only in zero-field techniques, e.g. Cryopad[1], for measuring the full polarisation tensor for single Bragg peaks on monochromatic instruments. Here we present a more powerful alternative route to spherical polarimetry based on a precession technique [2,3] that can be fully adapted to a pulsed, polychromatic neutron beam and enables us to cover simultaneously a large section of the reciprocal space in time-of-flight Laue diffraction. Implementing spherical polarimetry by precession on the instrument MAGIC requires precise magnetic field design. Two coils in the incoming beam path rotate the polarisation with respect to the field axis, determining inclination and precession angles. Both coils are ramped in time according to the neutrons’ speed. A common phase angle is achieved by an additional, time-independent spin-echo coil. Full simulations of the polarised neutron transport on the instrument MAGIC not only demonstrate the feasibility of spherical polarimetry but also its excellent performance. [1] F. Tasset, Zero field neutron polarimetry. Physica B: Cond. Mat. 156, 627-630 (1989).[2] W. Schweika, Time-of-flight and vector polarization analysis for diffuse neutron scattering. Physica B: Cond. Mat. 335,157 -163 (2003).[3] W. Schweika, S. Easton and K.U. Neumann. Vector Polarization Analysis on DNS. Neutron News, 16(2), 14-17 (2005)
Late emergence of pathological oscillatory activity in the retina of the Retinitis pigmentosa model RCS (Royal College of Surgeons) rat
No full textRetinitis pigmentosa (RP) is a leading cause of blindness. The best studied modelsof human RP are the rd1 and rd10 mouse and the RCS rat (Royal College of Surgeons).In many models after degeneration of the photoreceptors, a pathologicalrhythmic activity of the retina as well as lowered efficiency of electrical stimulationwere observed. In rd10 retina, both events were shown to be intimately linked. Surprisingly,to our knowledge no retinal oscillations have been reported in RCS retina.As oscillations might interfere with the performance of therapeutic approaches torestore vision, e.g., retinal prostheses, it is important to know, whether they are acommon feature of retinal degeneration. Electrical activity was recorded in retinaeof 3–19 months (M3-19) old RCS rats in vitro using planar and penetrating multielectrode-arrays. Short deflections in the local field potential resembling thoseobserved in oscillations in rd1 and rd10 retinae were only sporadically found inM3 RCS retinae. Oscillations at appr. 2 Hz occurred more often and were morepronounced the older the animals were. Yet, even at M18-19 oscillatory periodswere short and separated by long periods of non-oscillatory activity. In summary, inadvanced stages of degeneration, RCS retinae display oscillations similar to rd1 andrd10 retinae. However, in RCS retina oscillatory periods are shorter than in mousemodels and may, therefore, have escaped detection in earlier studies. These resultstogether with results observed in non-rodent models suggest that pathological rhythmicactivity is a common feature in RP models
Immune, Developmental, and Synaptic Pathways Define Bipolar Disorder Clinical Heterogeneity
No full textBehavior of Ashes and Inorganic Trace Elements During Combustion of Fuel Mixtures with Up to 100% Biomass
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Stratospheric Gravity waves in AIRS observations and high-resolution models
No full textAtmospheric gravity waves vary hugely in scale; with horizontal wavelengths ranging from a few to thousands of km. Typically, gravity waves are smaller than model grid-size and as a result, their effects are parametrised instead of being explicitly resolved. However, recent computational and scientific advancements have allowed for the development of higher resolution global-scale models. These models have horizontal resolutions of order a few km with around 1km vertical resolution in the stratosphere. At such scales, it should in principle be possible to accurately simulate the majority of GWs without relying on parametrisation.In this work, we use data from three models from the DYAMOND Initiative (DYnamics of the Atmospheric general circulation Modeled On Non-hydrostatic Domains). Specifically, IFS (Integrated Forecast System – produced by ECMWF) at 4km horizontal resolution, ICON (Icosahedral NonHydrostatic) at 5km horizontal resolution and GEOS (Goddard Earth Observing System model) at 3km horizontal resolution. All models are initialised with the same initial conditions and are free running for 40 days. We then compare the properties of resolved gravity waves with observations from the AIRS instrument (Atmospheric InfraRed Sounder) onboard NASA’s Aqua satellite. Importantly, we note that the AIRS observations are limited by the ‘observational filter’, wherein each observing system can only `see' a limited portion of the full GW spectrum. To account for this, an important step in this work is in resampling the model atmospheres as though viewed by the AIRS instrument.We compare the representation of resolved waves in the three models and AIRS observations across 40-days in Austral winter. We use a recently developed machine learning wave identification method to separate gravity waves in the dataset and determine gravity wave occurrence frequencies. Next, we use spectral analysis to estimate gravity wave amplitudes, wavelengths and calculate momentum fluxes and the intermittency of gravity waves. This work provides an essential evaluation of the accuracy of current gravity wave modelling capabilities