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Nondestructive imaging with both a large field of view and a high spatial resolution is crucial to understand complex materials and processes in science and technology. X-ray ptychography can provide highest spatial resolution but is limited in the field of view by the acquisition time and coherent flux at modern x-ray sources. By multi-beam ptychography, the sample can be imaged in parallel by se

We report on the manufacturing and testing of the first nanofocusing refractive lenses made of single-crystal silicon carbide. We introduce the fabrication process based on lithography, followed by deep isotropic etching. The lenses were characterized at the energy of 12 keV at the beamline P06 of the synchrotron radiation source PETRA III. A focal spot of 186 nm x 275 nm has been achieved with a

X-rays allow to non-destructively investigate biological, chemical or physical processes at thenano-scale. Their high penetration depth in matter allows to investigate samples even in-side sample environments, which would be difficult with complementary methods such astransmission electron microscopy (TEM). The microscopy technique ptychography has beenestablished in X-ray imaging in recent years.X-rays allow to non-destructively investigate biological, chemical or physical processes at the nano-scale. Their high penetration depth in matter allows to investigate samples even inside sample environments, which would be difficult with complementary methods such as transmission electron microscopy (TEM). The microscopy technique ptychography has been established in X-ray imaging in recent year

BackgroundUnderstanding of the impacts of climatic variability on human health remains poor despite a possibly increasing burden of vector-borne diseases under global warming. Numerous socioeconomic variables make such studies challenging during the modern period while studies of climate–disease relationships in historical times are constrained by a lack of long datasets. Previous studies have ide

Extracting relevant features from data sets where the number of observations n is much smaller then the number of predictors p is a major challenge in modern statistics. Sorted L-One Penalized Estimation (SLOPE)—a generalization of the lasso---is a promising method within this setting. Current numerical procedures for SLOPE, however, lack the efficiency that respective tools for the lasso enjoy, p

Background: This study investigates the patterns of PET-positive lymph nodes (LNs) in anal cancer. The aim was to provide information that could inform future anal cancer radiotherapy contouring guidelines. Methods: The baseline [18F]-FDG PET-CTs of 190 consecutive anal cancer patients were retrospectively assessed. LNs with a Deauville score (DS) of ≥3 were defined as PET-positive. Each PET-posit

If scientists with PhDs don’t understand what Google results are and what they can tell us, what hope do the rest of us have?

This thesis addresses three different topics on the interaction between light and matter in open quantum systems. The first topic concerns two-dimensional spectroscopy and the spectral contributions from different nonlinear action signals with a focus on how to differentiate between them. The second topic concerns the thermalization of excited electrons in hot-carrier solar cells with a focus on h

This report aims at identifying common causes, patterns, and effects of changing foreign investments across the countries of Central Asia. Experience of neighboring countries in Central Asia as a distinct region of the world attracting foreign investment is particularly relevant for each country in the area. Therefore, the comparative analysis of the Central Asian countries presented in this repor

Twisted bilayer graphene (TBG) has been experimentally observed to exhibit almost flat bands when the twisting occurs at certain magic angles. In this Letter we show that in the approximation of vanishing AA coupling, the magic angles (at which there exist entirely flat bands) are given as the eigenvalues of a non-Hermitian operator, and that all bands start squeezing exponentially fast as the ang

The autonomic nervous system (ANS) is an important factor in cardiac arrhythmia, and information about ANS activity during atrial fibrillation (AF) may contribute to personalized treatment. In this study we aim to quantify respiratory modulation in the f-wave frequency trend from resting ECG. First, an f-wave signal is extracted from the ECG by QRST cancelation. Second, an f-wave model is fitted t

Among plants, gender dimorphism occurs in about 10% of all angiosperms and more than 50% of all moss taxa, with dwarf males (DM) found exclusively in some unisexual mosses. In this study, we explore the role of male dwarfism as a reproductive strategy in the widespread acrocarpous moss Dicranum scoparium, which has facultative male dwarfism, having both dwarf males (DMs) and normal-sized males (NM

OBJECTIVE: The optimal target heart rate in patients with prevalent atrial fibrillation (AF) is not well defined. The aim of this study was to analyse the associations between heart rate and adverse outcomes in a large contemporary cohort of patients with prevalent AF.METHODS: From two prospective cohort studies, we included stable AF outpatients who were in AF on the baseline ECG. The main outcom

We explore the interplay of electron-electron correlations and surface effects in the prototypical correlated insulating material, NiO. In particular, we compute the electronic structure, magnetic properties, and surface energies of the (001) and (110) surfaces of paramagnetic NiO using a fully charge self-consistent DFT+ dynamical mean-field theory method. Our results reveal a complex interplay b

Ekosystemtjänster är alla nyttor som ett fungerande ekosystem ger människan. Att bevara jordbruksmarkens ekosystemtjänster kan vara kostsamt för jordbrukare och då krävs det att de nyttor som tjänsterna ger syns och att bevarandet av ekosystemtjänster är lönsamt. Vi har utvecklat verktyg för att kvantifiera och värdera ekosystemtjänster. Vi presenterar dessa verktyg och visar att:- När det blir lä

Alexander Lingas, Anna Stavrakopoulou, and Thomas Arentzen discuss and present the poetry and music of Byzantium's most outstanding female composer.