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Detection of calcification clusters in digital breast tomosynthesis slices at different dose levels utilizing a SRSAR reconstruction and JAFROC

Purpose: To investigate detection performance for calcification clusters in reconstructed digital breast tomosynthesis (DBT) slices at different dose levels using a Super Resolution and Statistical Artifact Reduction (SRSAR) reconstruction method. Method: Simulated calcifications with irregular profile (0.2 mm diameter) where combined to form clusters that were added to projection images (1-3 clus

Core excitations of naphthalene: Vibrational structure versus chemical shifts

High-resolution x-ray photoelectron emission (XPS) and near-edge x-ray absorption fine structure (NEXAFS) spectra of naphthalene are analyzed in terms of the initial state chemical shifts and the vibrational fine structure of the excitations. Carbon atoms located at peripheral sites experience only a small chemical shift and exhibit rather similar charge-vibrational coupling, while the atoms in th

The role of rosiglitazone treatment in the modulation of islet hormones and hormone-like peptides: a combined in situ hybridization and immunohistochemical study

Rosiglitazone, peroxisome proliferator-activated receptor-gamma agonist, is an insulin sensitizing agent in peripheral tissues. This study investigated islet hormones and hormone-like peptides expression patterns in rosiglitazone treated streptozotocin (STZ)-diabetic rats by using immunohistochemistry and in situ hybridization methods. Animals were divided into four groups. I. Group: Intact contro

Laser-induced fluorescence imaging for studies of cultural heritage - art. no. 66180P

Laser-induced fluorescence for remote imaging of historical monuments is an established technique, which in this work has been used in measurement campaigns at the Coliseum and the Baptistery of San Giovanni in Laterano in Rome, Italy. The results presented here are examples that show that biodeteriogens can be monitored and that. materials can be identified. Also, cleaned and soiled areas on the

Note on soft graviton theorem by KLT relation

Recently, new soft graviton theorem proposed by Cachazo and Strominger has inspired a lot of works. In this note, we use the KLT-formula to investigate the theorem. We have shown how the soft behavior of color ordered Yang-Mills amplitudes can be combined with KLT relation to give the soft behavior of gravity amplitudes. As a byproduct, we find two nontrivial identities of the KLT momentum kernel

Ecosystem productivity and carbon cycling in intact and annually burnt forest at the dry southern limit of the Amazon rainforest (Mato Grosso, Brazil)

Background: The impact of fire on carbon cycling in tropical forests is potentially large, but remains poorly quantified, particularly in the locality of the transition forests that mark the boundaries between humid forests and savannas. Aims: To present the first comprehensive description of the impact of repeated low intensity, understorey fire on carbon cycling in a semi-deciduous, seasonally d

In vitro experiment using porcine artery for evaluation of ultrasonic measurement of arterial luminal surface profile

Introduction In early-stage atherosclerosis, the luminal surface of the arterial wall becomes rough because of detachment of endothelial cells and degeneration of the internal elastic layer. Therefore, it would be useful if minute luminal surface roughness of the carotid arterial wall, which occurs in the early stage of atherosclerosis, could be measured noninvasively with ultrasound. The injured

Fluorescence enhancement of single DNA molecules confined in Si/SiO2 nanochannels

We demonstrate that the detected emission intensity from YOYO-labeled DNA molecules confined in 180 nm deep Si/SiO2 nano-funnels changes significantly and not monotonically with the width of the funnel. This effect may be of importance for quantitative fluorescence microscopy and for experiments with a tight photon budget.

Simulations of time series of atmospherically distorted wavefronts

A comparatively simple way to generate time series of atmospherically distorted wave fronts is described and tested. Temporal power spectra of Zernike aberrations, extracted from the time series, agree very well with theoretical predictions. A method for generation of longer time series is also shown to give results in accordance with theory, except for the lowest temporal frequencies modeled. A w

Supply chain security - mitigation measures and a logistics multi-layered framework

Statistics show that large amounts of goods moved in distribution chains incur the risk for being stolen, counterfeited or contaminated. At the same time terror threats for smuggling weapons of mass destructions, or intentionally altering products, are pushing governments to require higher security from logistics and transport operators. As a consequence, supply chain managers have to face the dif

Knowledge Links in High-Technology Industries: Markets, Networks, or Milieu? The Case of the Vienna Biotechnology Cluster

In recent years, the innovation process in biotechnology has become a subject of major interest to scholars from different disciplines. Despite an ever growing body of work, the nature of knowledge links and their particular geography remain a highly disputed issue. The purpose of this paper is to shed some light on this topic. We will develop a model of knowledge interactions distinguishing betwe

Investigation of the risk factors for tuberculosis: a case-control study in three countries in West Africa

BACKGROUND: Host-related and environment-related factors have been shown to play a role in the development of tuberculosis (TB), but few studies were carried out to identify their respective roles in resource-poor countries. METHODS: A multicentre case-control study was conducted in Guinee, Guinea Bissau, and The Gambia, from January 1999 to March 2001. Cases were newly detected smear positive TB

The publics perception of the prehospital emergency care in the county of Skane, southern Sweden

Abstract Introduction: The prehospital emergency care has had a rapid progress in Sweden in terms of technology, treatments and personnel education demands. In the County of Skane there is at least one specialized nurse in every ambulance. Possible misuses of the resources by the public have been acknowledged. Aim: To investigate the public’s use, knowledge and expectations of the prehospital emer

Longitudinal relaxation in dipole-coupled homonuclear three-spin systems: Distinct correlations and odd spectral densities.

A system of three dipole-coupled spins exhibits a surprisingly intricate relaxation behavior. Following Hubbard's pioneering 1958 study, many authors have investigated different aspects of this problem. Nevertheless, on revisiting this classic relaxation problem, we obtain several new results, some of which are at variance with conventional wisdom. Most notably from a fundamental point of view, we

Analysis of case-control association studies with known risk variants

Motivation: The question of how to best use information from known associated variants when conducting disease association studies has yet to be answered. Some studies compute a marginal P-value for each Several Nucleotide Polymorphisms independently, ignoring previously discovered variants. Other studies include known variants as covariates in logistic regression, but a weakness of this standard