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1Scientific Reports | 6:30828 | DOI: 10.1038/srep30828 www.nature.com/scientificreports A Comparison of Rule-based Analysis with Regression Methods in Understanding the Risk Factors for Study Withdrawal in a Pediatric Study Mona Haghighi1, Suzanne Bennett Johnson2, Xiaoning Qian3, Kristian F. Lynch4, Kendra Vehik4, Shuai Huang5 & The TEDDY Study Group† Regression models are extensively used in man

https://www.teddy.lu.se/sites/teddy.lu.se/files/2021-11/61%2010042016_679_61_MP99_Haghighi_SciRep_2016.pdf - 2026-09-19

Wear in forming tools and contact problems between sheet-metal and tool-material are common problems in manufacturing industries and sheet-metal-parts production. In this paper recent tool material experiences are presented. Quantitative determination of wear has been performed using micro hardness indentions made on the tool surface prior to pressings and thereafter measured. Wear tests are perfo

In the last decades, the growing competitiveness of the market has continuously driven the forming companies to highly optimize their products regarding offered performance at minimum cost. In order to achieve better products, studies where conducted with different material models when simulating the forming process of titanium. The material is often used in heat exchanger applications. Titanium h

Hydrogen normally occurs as hydroxyl ions related to defects at specific crystallographic sites in the structures, and is normally characterized by infrared spectroscopy (FTIR). For quantification purposes the FTIR technique has proven to be less precise since calibrations against independent methods are needed. Hydrogen analysis by the NMP technique can solve many of the problems, due to the low

In the new sub-micron beamline at the Lund Nuclear Microprobe facility a special large area HPGe X-ray detector has been installed. It consists of eight 100-mm(2)-size detector elements arranged in an annular formation around the beam entrance hole. Different parameters like FWHM, FWTM, peak-to-background ratio and peak-to-valley ratio for each individual detector element as well as their sum spec

Finger jointing of unseasoned Norway Spruce was studied with respect to tensile strength, adhesive penetration and durability. Finger joints were manufactured with 1) unseasoned wood and one component polyurethane (PUR) adhesive, 2) dried wood and PUR adhesive and 3) dried wood and phenol resorcinol formaldehyde (PRF) adhesive. Two levels of wood density were used. The tensile strength of the f

The Department of Physics at Lund University is participating in a European Union project called EUMAPP (European Union Microdose AMS Partnership Programme), in which sample preparation and accelerator mass spectrometry (AMS) measurements of biological samples from microdosing studies have been made. This paper describes a simplified method of converting biological samples to solid graphite for C-

This contribution presents a sample preparation methodology to enable the identification, with synchrotron radiation-based analytical techniques, of the gettering sites of metallic impurities on the internal walls of implantation-induced nanocavities in Si substrates. Preliminary results for the Cu-Si and Cu-Cu bond lengths on the internal surface of the nanocavities are reported. (C) 2002 Elsevie

The creation spectra of F centres by synchrotron radiation of 5-35 eV have been measured for Na6Al6Si6O24(NaI)(2x) and Na6Al6Si6O24(NaBr)(2x) optical ceramics at 8 and 80 K. The exciting photons cause the excitation and ionization of halogen ions (6-8 eV) and of an aluminosilicate carcass (8.5-31 eV) or the excitation of Na+ ions (32-35 eV). An exciting photon of 20-26 and 27-31 eV creates two or

Methods of VUV electron beam ion trap (EBIT) spectroscopy are applied to the study of Pm-like tungsten (W13+). These data show that theory appears well capable of dealing with these multi-electron (61) ions, at least for high ionization stages. A comparison of other spectroscopic methods applied to the study of other ions of the Pm I sequence is also given, and finally a search for the Pm-like W l

A system for ion beam tomography has been implemented in conjunction with the new sub-micron bearriline at the Lund Nuclear Microprobe laboratory. The first version of the system is dedicated to STIM (scanning transmission ion microscopy) tomography for three-dimensional mass density analysis, but future development will allow also PIXE (particle induced X-ray emission) tomography for elemental an

The permeability of skin to nanoparticles of titanium dioxide (TiO2) used in sunscreens as a reflector of the UV wavelengths of sunlight, was examined using nuclear microscopy techniques. Special attention was given to the permeation characteristics of these nanoparticles across the outer layers of skin, the stratum corneum, in healthy and psoriatic skin condition. Aspects that may influence the i

A new sub-micron beamline for high-resolution nuclear microprobe applications has been constructed at the Lund nuclear microprobe facility. The design and construction of the main experimental chamber.. sample viewing system and computer controlled precision sample stage movement is presented in this paper. The chamber is especially designed for using a large area annular HPGe detector. The advant

The evolution of carbon-oxygen-related defects upon isochronal annealing (75-325 degrees C in 25 degrees C steps for 30 min at each temperature) in electron irradiated Si crystals has been studied by means of local vibrational mode (LVM) spectroscopy. A complicated annealing behaviour of the LVMs related to the C4 (ICiOi) defect has been observed. At about 200 degrees C the bands at 940 and 1024 c

The interaction of ink and newspaper has been investigated and the specific question of penetration of ink into the paper has been addressed with a nuclear microprobe using particle induced X-ray emission, The penetration depth of the newsprint is a critical factor in terms of increasing the quality of newsprint and minimising the amount of ink used. The objective of the experiment was to relate t

A new experimental setup for quantitative hydrogen isotopic-ratio microscopy in thin samples (up to 12 mu m) is under development at the Lund Ion Beam Analysis Facility. This technique is derived from the proton-proton scattering technique and has been proven to have the same beneficial features, namely a detection limit below 1 wt-ppm and a depth resolution better than 1 mu m. The method gives ab

The possibility to study variations in the oxygen isotopic ratio with photon tagged nuclear reaction analysis (pNRA) is evaluated in the current work. The experiment described in the article was performed at Lund Ion Beam Analysis Facility (LIBAF) with a 2 MeV deuteron beam. Isotopic fractionation of light elements such as carbon, oxygen and nitrogen is the basis of many analytical tools in hydrol

OBJECTIVE: Q-space trajectory imaging (QTI) enables detailed characterization of tissue microstructure. Achieving high spatial resolution is challenging due to low signal-to-noise ratio (SNR), particularly on clinical MRI systems with limited gradient capabilities and coil options. This study assessed the potential of denoising methods to improve the resolution of QTI in the brain on a radiotherap

Towards the improvement of the understanding of force/stress distribution in granular media under load, a new experimental approach is suggested. Neutron diffraction, a non-conventional experimental technique, has been successfully used to map the evolution of intragranular strains in sand specimens loaded in a novel plane-strain apparatus. Representative preliminary results from recent experiment