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Excessive White Matter Hyperintensity Increases Susceptibility to Poor Functional Outcomes After Acute Ischemic Stroke
Objective: To personalize the prognostication of post-stroke outcome using MRI-detected cerebrovascular pathology, we sought to investigate the association between the excessive white matter hyperintensity (WMH) burden unaccounted for by the traditional stroke risk profile of individual patients and their long-term functional outcomes after a stroke. Methods: We included 890 patients who survived
Ion-induced nanopatterns on semiconductor surfaces investigated by grazing incidence x-ray scattering techniques
In this review we cover and describe the application of grazing incidence x-ray scattering techniques to study and characterize nanopattern formation on semiconductor surfaces by ion beam erosion under various conditions. It is demonstrated that x-rays under grazing incidence are especially well suited to characterize (sub)surface structures on the nanoscale with high spatial and statistical accur
Order parameter segregation in Ce0.7La0.3B6 : 4f octopole and 5d dipole magnetic order
The intriguing thermophysical properties of CeB6 have been subject to investigation for more than 20 years. In particular, an exotic ground state, phase IV, emerges under doping with La. We report resonant x-ray scattering results on the order parameter symmetries in phase IV of Ce0.7La0.3B6, which condenses below TIV=1.5K. The results reveal a degree of mesoscopic 5d dipole antiferromagnetic orde
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Biaxial strain and orbital order in la2/3Ca 1/3MnO3 thin films
Biaxially strain is an important parameter in the complex phase diagram of the doped manganites that can lead to a different groundstate compared to bulk single crystals at the same doping level. For coherently strained La 2/3Ca1/3MnO3 thin films on SrTiO3 substrates, we report an unusual direction dependence of the electrical transport properties. For transport perpendicular to the substrate indu
Transport anisotropy in biaxially strained La2/3Ca1/3MnO3 thin films
Due to the complex interplay of magnetic, structural, electronic, and orbital degrees of freedom, biaxial strain is known to play an essential role in the doped manganites. For coherently strained La2/3Ca1/3MnO3 thin films grown on SrTiO3 substrates, we measured the magnetotransport properties both parallel and perpendicular to the substrate and found an anomaly of the electrical transport propert
Efficient high area OFETs by solution based processing of a π-electron rich donor
We report on the preparation of high performance field-effect transistors (FETs) based on large areas of aligned films of a TTF derivative, namely, tetrakis-(octadecylthio)-tetrathiafulvalene (TTF-4SC18). TTF-4SC18 assembles into one-dimensional stacks in which the long alkyl chains promote intermolecular π-π overlapping due to their extremely closely packed nature. The films were prepared from so
Spin and orbital magnetic moments in carbon-encapsulated Fe50 Pt50 nanoparticles
X-ray absorption and magnetic circular dichroism spectra of as-deposited and postannealed Fe50 Pt50 /C granular multilayers were measured at both the Fe and Pt L2,3 edges. We demonstrate that the partial L 10 ordering of the FePt nanoparticles induced by thermal annealing results in an increase of the effective spin magnetic moments by 200% at the Fe site and by 65% at the Pt site, while the orbit
Early stage of ripple formation on Ge(001) surfaces under near-normal ion beam sputtering
We present a study of the early stage of ripple formation on Ge(001) surfaces irradiated by a 1 keV Xe+ ion beam at room temperature and near-normal incidence. A combination of a grazing incidence x-ray scattering technique and atomic force microscopy allowed us to observe a variation of the symmetry of the surface nanopattern upon increase of the ion fluence. The isotropic dot pattern formed duri
X-ray structure analysis of free-standing lipid membranes facilitated by micromachined apertures
Silicon and Teflon substrates have been structured by wet etching and a focused ion beam (FIB) to obtain very defined, clean apertures. Planar, free-standing lipid membranes (black lipid membranes (BLM)) with enhanced long-term stability have been prepared on these apertures by the methods of Montal and Müller1.2 as well as Müller and Rudin. 3 The stability and geometric control enables the use of
Multilayer films from templated TiO2 and structural changes during their thermal treatment
This work is focused on synthesis, characterization, and determination of main parameters of the multilayer P123 templated TiO2 films. The mesoporous multilayer thin films consist of TiO2 nanoparticles on the F-doped SnO2 (FTO) conductive glass substrates. The films were grown by implementing the protocol of supramolecular templating with the amphiphilic triblock copolymer, Pluronic P123. The temp
Versatile vacuum chamber for in situ surface X-ray scattering studies
A compact portable vacuum-compatible chamber designed for surface X-ray scattering measurements on beamline ID01 of the European Synchrotron Radiation Facility, Grenoble, is described. The chamber is versatile and can be used for in situ investigation of various systems, such as surfaces, nanostructures, thin films etc., using a variety of X-ray-based techniques such as reflectivity, grazing-incid
X-ray scattering and diffraction from ion beam induced ripples in crystalline silicon
We report on periodic ripple formation on Si(001) surfaces after bombardment with Xe+ ions with energies between 5 and 35 keV under incidence angles of 65° and 70°. The sputter process leads to the formation of a rippled amorphous surface layer, followed by a rippled interface toward crystalline material. Using grazing-incidence small-angle scattering and diffraction, we show that the surface morp
Amyloid β 42 fibril structure based on small-angle scattering
Amyloid fibrils are associated with a number of neurodegenerative diseases, including fibrils of amyloid β42 peptide (Aβ42) in Alzheimer's disease. These fibrils are a source of toxicity to neuronal cells through surface-catalyzed generation of toxic oligomers. Detailed knowledge of the fibril structure may thus facilitate therapeutic development. We use small-angle scattering to provide informati
Novel synthesis of the TiO2(B) multilayer templated films
TiO2(B) mesoporous thin films were grown in two steps on the F-doped SnO2 conductive glass substrates. In the first step, a small amount of H3PO4, corresponding to 0.15-0.375 wt % P on TiO2 basis, was introduced into concentrated HCl which was subsequently used for hydrolysis of titanium ethoxide. The hydrolyzed colloidal TiO2 suspension was further mixed with a 1-butanol solution of the amphiphil
Transition from smoothing to roughening of ion-eroded GaSb surfaces
During ion sputtering of GaSb(100) surfaces a transient behavior from initial smoothing to roughening accompanied by self-organized pattern formation has been observed using in situ x-ray reflectivity and grazing incidence small angle scattering. The induced patterns show hexagonally ordered nanodot arrays with a spatial periodicity of 30 nm. The correlation length of the pattern increases with io
X-ray coherent diffraction imaging with an objective lens : Towards three-dimensional mapping of thick polycrystals
We demonstrate an X-ray coherent imaging method that combines high spatial resolution with the ability to map grains within thick polycrystalline specimens. An X-ray objective serves to isolate an embedded grain. Iterative oversampling routines and Fourier synthesis are used to reconstruct the shape and strain field from the far-field intensity pattern. In a demonstration experiment a ∼500-nm Pt g
Deployment of Negative Emissions Technologies at the National Level : A Need for Holistic Feasibility Assessments
The 2015 Paris Agreement aims to strengthen the global response to climate change, and to maintain an average global temperature well below 2°C, with aspirations toward 1.5°C, by means of balancing sources and sinks of greenhouse gas emissions. Following this, the importance of carbon dioxide removal in global emission pathways has been further emphasized, and Negative Emissions Technologies (NETs
Synthesis of CdS nanocrystals in polymeric films studied by in-situ GID and GISAXS
In this work, we describe the synthesis of CdS nanocrystals in thin polymeric films by in-situ Grazing Incidence Diffraction (GID) and Grazing Incidence Small Angle Scattering (GISAXS). The 2D GISAXS patterns indicate how the precursor structure is altered as the temperature is varied from 25°C to 300°C. At 150°C, the CdS nanocrystals start to arrange themselves in a hexagonal lattice with a latti