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Fabrication of x-ray gratings for interferometric imaging by conformal seedless gold electroplating

We present a method to produce small pitch gratings for X-ray interferometric imaging applications, allowing the phase sensitivity to be increased and/or the length of the laboratory setup to be minimized. The method is based on fabrication of high aspect ratio silicon microstructures using deep reactive ion etching (Bosch technique) of dense grating arrays and followed by conformal electroplating

Fast acquisition protocol for X-ray scattering tensor tomography

Microstructural information over an entire sample is important to understand the macroscopic behaviour of materials. X-ray scattering tensor tomography facilitates the investigation of the microstructural organisation in statistically large sample volumes. However, established acquisition protocols based on scanning small-angle X-ray scattering and X-ray grating interferometry inherently require l

Exploration of the X-ray Dark-Field Signal in Mineral Building Materials

Mineral building materials suffer from weathering processes such as salt efflorescence, freeze-thaw cycling, and microbial colonization. All of these processes are linked to water (liquid and vapor) in the pore space. The degree of damage following these processes is heavily influenced by pore space properties such as porosity, pore size distribution, and pore connectivity. X-ray computed micro-to

Release of prolactin as well as adrenocorticotropin after administration of arginine-vasopressin to healthy men

The study was undertaken to obtain simultaneous measurements of circulating anterior pituitary hormone levels after the i.v. injection of arginine-vasopressin (AVP). Nine healthy men, mean age 31 years (range 24-41), received single blind with at least one week apart, after resting in the supine position for 30 min, AVP 0.26 microgram/kg body weight i.v. (Pitressin, Parke-Davis) or saline in rando

Metasurface-Enabled Holographic Lithography for Impact-Absorbing Nanoarchitected Sheets

Nanoarchitected materials represent a class of structural meta-materials that utilze nanoscale features to achieve unconventional material properties such as ultralow density and high energy absorption. A dearth of fabrication methods capable of producing architected materials with sub-micrometer resolution over large areas in a scalable manner exists. A fabrication technique is presented that emp

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Polsk översättning av min engelska artikel i The Conversation

Optimization of the visibility of a tunable dual-phase x-ray grating interferometer

Dual-phase x-ray grating interferometry (DP-XGI) is a recently developed imaging technique that can retrieve structural information in the sub-micro scale over areas in the millimeter range. This is performed by use of the scattering signal, which is sensitive to structures that lie below the intrinsic spatial resolution of the imaging system. A quantitative understanding of the microstructure is

Tomographic Reconstruction of the Small-Angle X-Ray Scattering Tensor with Filtered Back Projection

Small-angle x-ray scattering tensor tomography provides three-dimensional information on the unresolved material anisotropic microarchitecture, which can be hundreds of times smaller than an image pixel. We develop a direct filtered back-projection method based on algebraic filters that enables rapid tensor-tomographic reconstructions and is a few orders of magnitude faster compared to established

Envelope modulated x-ray grating interferometry

X-ray dark-field and phase contrast imaging using grating interferometry (GI) have demonstrated great potential for medical and industrial applications. GI relies on the fabrication of high-quality absorption gratings, which has revealed to be quite challenging. This paper proposes an interferometer for dark-field and differential phase contrast imaging using a single phase-shifting element. This

Macroscopic mapping of microscale fibers in freeform injection molded fiber-reinforced composites using X-ray scattering tensor tomography

Fiber-reinforced composites deliver lightweight but strong structures that are crucial in applications ranging from aerospace to the automotive industry. The advent of freeform injection molding has made the manufacturing of complex fiber-reinforced composites with full design freedom possible. Prediction of the mechanical properties, dictated by the local microfiber orientation, is essential for

Vertical III-V nanowire tunnel field-effect transistors : a circuit perspective

The energy scaling of integrated circuits has reached its limit because the operating voltage of Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFET) based switches has reached its minimum value. MOSFETs are limited by thermionic emission and cannot achieve a subthreshold swing (SS) below 60 mV/decade at room temperature. Tunnel Field-Effect Transistors (TFET), which operate on field modula

Needs, barriers and facilitators for a healthier lifestyle in haemodialysis patients : The GoodRENal project

Background: Malnutrition, sedentary lifestyle, cognitive dysfunction and poor psychological well-being are often reported in patients on haemodialysis (HD). Aims: We aimed to explore needs, barriers and facilitators—as perceived by patients, their carers, and healthcare professionals (HCPs) for increasing the adherence to the diet, to physical activity and cognition and psychological well-being. M

Path Planning Using Wasserstein Distributionally Robust Deep Q-learning

We investigate the problem of risk averse robot path planning using the deep reinforcement learning and distributionally robust optimization perspectives. Our problem formulation involves modelling the robot as a stochastic linear dynamical system, assuming that a collection of process noise samples is available. We cast the risk averse motion planning problem as a Markov decision process and prop

Moving Target Detection Using a Distributed MIMO Radar System With Synchronization Errors

This article addresses the detection and estimation problems of a distributed multiple-input and multiple-output (MIMO) radar system with synchronization errors. In such cases, the outputs of all waveform-specific matched filters contain errors in the resulting time delay estimates, which will cause biases in the corresponding estimation of the active range cells. To overcome the impact resulting

Professional Activism : AIDS and Civil Society in Sweden, 1982–2000

The Swedish HIV/AIDS epidemic accelerated the hybridisation of welfare, as volunteer organisations rapidly professionalised and expanded their welfare services. The media’s horror scenarios prompted a sense of urgency which, in turn, motivated politicians and state funding agencies to channel large amounts of money into Swedish volunteer organisations. These included RFSL (the National Union for S