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Three-dimensional X-ray fourier transform holography : The Bragg case

A novel approach to determine the structure of nanoscale crystals in three dimensions is proposed by the use of coherent x-ray Fourier transform holography in Bragg geometry. The full internal description is directly obtained by a single Fourier transform of the 3D intensity hologram. Together with the morphology, Bragg geometry gives access to the 3D displacement field within the crystal. This re

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

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

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

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

A superbright X-ray laboratory microsource empowered by a novel restoration algorithm

The properties of nanoscale materials vary with the size and shape of the building blocks, which can be measured by (grazing-incidence) small-angle X-ray scattering along with the mutual positions of the nanoparticles. The accuracy in the determination of such parameters is dependent on the signal-to-noise ratio of the X-ray scattering pattern and on the visibility of the interference fringes. Her

Exploring Narratives on Negative Emissions Technologies in the Post-Paris Era

The 2015 Paris Agreement specified that the goal of international climate policy is to strengthen the global response to climate change by restricting the average global warming this century to “well below” 2°C above pre-industrial levels and to pursue efforts to limit it to 1.5°C. In this context, “Negative Emissions Technologies” (NETs)—technologies that remove additional greenhouse gases (GHGs)

Diamonds for X-ray optical applications at 3rd and 4 th generation X-ray sources

There is currently interest in low strain HPHT diamond due to its expected application as various types of X-ray optical elements at Synchrotrons, where the X-ray intensity is becoming progressively too severe for the existing materials. The diamond crystals need to be synthesised with unprecedented lattice quality. In recent measurements at the ID19 beamline of European Synchrotron Radiation Faci

Combining dense and sparse labeling in optical DNA mapping

Optical DNA mapping (ODM) is based on fluorescent labeling, stretching and imaging of single DNA molecules to obtain sequence-specific fluorescence profiles, DNA barcodes. These barcodes can be mapped to theoretical counterparts obtained from DNA reference sequences, which in turn allow for DNA identification in complex samples and for detecting structural changes in individual DNA molecules. Ther

Analysis and optimization by micro-beam X-ray diffraction of Al- GaInAs heterostructures obtained by Selective Area Growth for optoelectronic applications

Growth of AlGaInAs/InP heterostructures by Selective Area Metal Organic Vapour Phase Epitaxy is investigated in this paper using advanced characterization techniques and numerical modelling. Synchrotron radiation and X-Ray optics allow to have micro or sub-micro X-Ray probe. With this probe, it is possible to characterize our samples by X-Ray Diffraction on very restricted area. This technique was

Importance of family history of colorectal carcinoma in situ versus invasive colorectal cancer : A nationwide cohort study

Background: The aim of this study was to explore the risk of invasive colorectal cancer (CRC) in relatives of patients with colorectal carcinoma in situ (CCIS), which is lacking in the literature. Patients and Methods: We collected data from Swedish family-cancer datasets and calculated standardized incidence ratio (SIR) and cumulative risk of CRC in family histories of CCIS in first- and second-d

Laminar burning velocity of lean methane/air flames under pulsed microwave irradiation

Laminar burning velocity of lean methane/air flames exposed to pulsed microwave irradiation is determined experimentally as part of an effort to accurately quantify the enhancement resulting from exposure of the flame to pulsed microwaves. The experimental setup consists of a heat flux burner mounted in a microwave cavity, where the microwave has an average power of up to 250 W at an E-field in th

Betting on the underdog : The influence of social networks on vote choice

People are commonly expected not to waste their vote on parties with small probabilities of being elected. Yet, many end up voting for underdogs. We argue that voters gauge the popular support for their preferred party from their social networks. When social networks function as echo chambers, a feature observed in real-life networks, voters overestimate underdogs' chances of winning. We conduct v

Long-term safety of Gadofosveset in clinical practice

Purpose: The purpose of this study was to systematically search for long-term complications, including Nephrogenic Systemic Fibrosis (NSF), in patients who were previously administered the gadolinium-based contrast agent Gadofosveset at our institute. Materials and methods: All patients who were administered Gadofosveset at our institute between 2006 and 2009 were identified in our Radiological In

GEANT4-based calibration of an organic liquid scintillator

A light-yield calibration of an NE 213A organic liquid scintillator detector has been performed using bothmonoenergetic and polyenergetic gamma-ray sources. Scintillation light was detected in a photomultipliertube, and the corresponding pulses were subjected to waveform digitization on an event-by-event basis. Theresulting Compton edges have been analyzed using a GEANT4 simulation of the detector

A comparative analysis of the dynamics of Plasmodium relictum (GRW4) development in the blood during single and co-infections

Although co-infections and interactions of parasites are a very common phenomenon in the wild, information received from studies on avian Plasmodium spp. is scarce and fragmented due to its complex nature. Different interactions of parasites and domination of one parasite may have a detrimental effect on transmission success of another pathogen. Untangling these interactions and competitive behavi

Non-Standard Errors

In statistics, samples are drawn from a population in a data generating process (DGP). Standard errors measure the uncertainty in sample estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence generating process (EGP). We claim that EGP variation across researchers adds uncertainty: non-standard errors. To study them, we let 164 teams test six hypoth