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Planar refractive lenses made of SiC for high intensity nanofocusing

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

3D nano-tomography using coherent X-rays

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

The spatiotemporal distribution of historical malaria cases in Sweden: a climatic perspective

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

The Strong Screening Rule For SLOPE

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

Patterns of pathologic lymph nodes in anal cancer : a PET-CT-based analysis with implications for radiotherapy treatment volumes

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

The Struggles of Light Bound in Matter : Modelling Optical Excitations in Nanostructures

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

Inflows of foreign direct investments in Central Asian countries between 1991 and 2020

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

Spectral characterization of magic angles in twisted bilayer graphene

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

Respiratory Induced Modulation in f-Wave Characteristics During Atrial Fibrillation

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

Genetic Diversity and Population Structure in Bryophyte With Facultative Nannandry

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

Heart rate and adverse outcomes in patients with prevalent atrial fibrillation

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

Electronic correlations at paramagnetic (001) and (110) NiO surfaces : Charge-transfer and Mott-Hubbard-type gaps at the surface and subsurface of (110) NiO

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

Mediatisation and social sustainability – an ambivalent relationship

Mediatisation is one of the central concepts by which to understand how the intensifying media and communications environment constructs our social world. The aim of research is to examine the conditions of sustainability communication in a media economy of visibility and recognition. To this end, we focus on how the phenomenon overtourism is constructed as a social sustainability challenge in new

Neuronal Replacement in Stem Cell Therapy for Stroke : Filling the Gap

Stem cell therapy using human skin-derived neural precursors holds much promise for the treatment of stroke patients. Two main mechanisms have been proposed to give rise to the improved recovery in animal models of stroke after transplantation of these cells. First, the so called by-stander effect, which could modulate the environment during early phases after brain tissue damage, resulting in mod