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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

Fragrance allergy in patients with hand eczema - a clinical study

Fragrance allergy and hand eczema are both common among dermatological patients. Fragrance mix (FM) and its constituents have a recognized relevance to exposure to fine fragrances and cosmetic products. Based on extensive chemical analysis and database search, a new selection of fragrances was established, including 14 known fragrance allergens present in products to which hand exposure would occu

Rapana thomasiana hemocyanin (RtH): Comparison of the two isoforms, RtH1 and RtH2, at 19 angstrom 16 angstrom resolution

Three-dimensional (3D) reconstructions of the two 8.4 MDa Rapana thomasiana hemocyanin isoforms, RtH1 and RtH2, have been obtained by cryoelectron microscopy of molecules embedded in vitreous ice and single particle image processing. The final 3D structures of the RtH1 and RtH2 didecamers at 19 angstrom and 16 angstrom resolution, respectively, are very similar to earlier reconstructions of gastro

Implementation of water calorimetry in a 180 MeV scanned pulsed proton beam including an experimental determination of k(Q) for a Farmer chamber

Water calorimetric measurements have been performed in a 180 MeV scanned pulsed proton beam and the absorbed dose determined has been compared with the results obtained using two NE2571 Farmer chambers and the IAEA TRS-398 code of practice. The depth of measurement in water corresponded to a residual range of R-res = 16.5 cm, corresponding to a mean energy of about 150 MeV. Ionization chambers wer

Solid-liquid-vapor metal-catalyzed etching of lateral and vertical nanopores.

Etching is an essential tool for the creation of nanostructures, where patterned metal structures can be used as masks. Here, we investigate HCl gas etching of InP substrates decorated with Au nanoparticles, and find that the etch rate is strongly increased at the Au-InP interfaces. The {111}A facets of the InP are preferentially etched. The metal nanoparticles follow in the etch direction, thereb

Emerging understanding of the ecosystem silica filter

The annual fixation of dissolved Si (DSi) into terrestrial vegetation has been estimated to range from 60 to 200 Tmole, or 10-40 times more than the yearly export of DSi and biogenic Si (BSi) from the terrestrial geobiosphere to the coastal zone. Ecosystems form a large filter between primary mobilization of DSi from silicate weathering and its eventual export to the oceans, and a large reservoir