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Comparing five different iterative reconstruction algorithms for computed tomography in an ROC study

The purpose of this study was to evaluate lesion conspicuity achieved with five different iterative reconstruction techniques from four CT vendors at three different dose levels. Comparisons were made of iterative algorithm and filtered back projection (FBP) among and within systems. An anthropomorphic liver phantom was examined with four CT systems, each from a different vendor. CTDIvol levels of

Development of an efficient statistical volumes of fluid-Lagrangian particle tracking coupling method

The breakup of a liquid jet into irregular liquid structures and droplets leading to the formation of a dilute spray has been simulated numerically. To overcome the shortcomings of certain numerical methods in specific flow regimes, a combined approach has been chosen. The intact liquid core, its primary breakup and the dense spray regime are simulated using the volumes of fluid (VOF) method in co

A niobium water target for routine production of [(18)F]Fluoride with a MC 17 cyclotron.

A [(18)F]Fluoride water target was constructed for a Scanditronix MC 17 cyclotron, without a beam line, with a typical wide beam of ∼30×5mm(2). Niobium was used as target chamber material. One hour irradiation with 45μA protons yields about 110GBq [(18)F]Fluoride. The saturation yield is 8.0±0.6GBq/μA (EOB). The FDG yield is 60±5% (EOS) with a TracerLab MX (G.E. Healthcare). More than 100GBq FDG i

Aspects of ‘physiognomic depiction’ in pictures : from macchia to microgenesis

“Figurativity”, roughly paraphrased as that which is not accounted for by the system, is a residue concept of both Piaget’s theory of cognitive development and of Greimasean semiotics. In the latter case, however, figurativity has been related to the second, so-called plastic layer of the picture, which is opposed to the pictorial layer, by means of which the picture is doing its job of depicting

Watching the dynamics of electrons and atoms at work in solar energy conversion

The photochemical reactions performed by transition metal complexes have been proposed as viable routes towards solar energy conversion and storage into other forms that can be conveniently used in our everyday applications. In order to develop efficient materials, it is necessary to identify, characterize and optimize the elementary steps of the entire process on the atomic scale. To this end, we

Pharmacokinetic digital phantoms for accuracy assessment of image-based dosimetry in (177)Lu-DOTATATE peptide receptor radionuclide therapy.

Patient-specific image-based dosimetry is considered to be a useful tool to limit toxicity associated with peptide receptor radionuclide therapy (PRRT). To facilitate the establishment and reliability of absorbed-dose response relationships, it is essential to assess the accuracy of dosimetry in clinically realistic scenarios. To this end, we developed pharmacokinetic digital phantoms correspondin

Use of astigmatic re-focusing at HP-XPS end-station

In this paper we present the refocusing optics for the new high pressure photoelectron spectroscopy (HP-XPS) branch line at MAX-lab, based on a plane grating monochromator with vertically collimated beam. For the HP-XPS instrument, the required spot size is dictated by the small geometric acceptance of the HP-XPS electron energy analyzer. Whereas a pair of bendable mirrors in a KB configuration ha

Assessment of myocardium at risk with contrast enhanced steady-state free precession cine cardiovascular magnetic resonance compared to single-photon emission computed tomography

Background: Final infarct size following coronary occlusion is determined by the duration of ischemia, the size of myocardium at risk (MaR) and reperfusion injury. The reference method for determining MaR, single-photon emission computed tomography (SPECT) before reperfusion, is impractical in an acute setting. The aim of the present study was to evaluate whether MaR can be determined from the con

Palaeogeographic, climatic and tectonic change in southeastern Australia: the Late Neogene evolution of the Murray Basin

The Murray Basin is a low-lying but extensive intracratonic depocentre in southeastern Australia, preserving an extraordinary record of Late Neogene sedimentation. New stratigraphic and sedimento-logic data allow the long-term evolution of the basin to be re-evaluated and suggest a significant role for: (1) tectonism in controlling basin evolution, and (2) progressive and step-wise climatic change

Characterization of the New Serum Protein Reference Material ERM-DA470k/IFCC: Value Assignment by Immunoassay

BACKGROUND: The availability of a suitable matrix reference material is essential for standardization of the immunoassays used to measure serum proteins. The earlier serum protein reference material ERM-DA470 (previously called CRM470), certified in 1993, has led to a high degree of harmonization of the measurement results. A new serum protein material has now been prepared and its suitability in

Functioning Numbness Instead of Feelings as a Direction : Young Adults’ Experiences of Antidepressant Use

In this article we explore, through in-depth interviews, young adults’ experiences of depression and antidepressant use in contemporary neoliberal society. We show that medication initially brings relief and an ability to function. However, in the longer perspective the dominating experience of antidepressants is emotional numbness. We suggest that this functioning yet numb subject is well suited

Gevrey hypoellipticity for a class of kinetic equations

In this paper, we study the Gevrey regularity of weak solutions for a class of linear and semi-linear kinetic equations, which are the linear model of spatially inhomogeneous Boltzmann equations without an angular cutoff

The classical versus the Cabrera presentation system for resting electrocardiography: Impact on recognition and understanding of clinically important electrocardiographic changes.

The classical system for presentation of the 12-lead electrocardiogram (ECG) reflects the electrical activity of the heart as viewed in the transverse plane by 6 leads with a single anatomically ordered sequence, V1-V6; but in the frontal plane by 6 leads with dual sequences, I, II, and III, and aVR, aVL, and aVF. However, there is also a single anatomically ordered sequence of leads, called the C

Herbal medicine, Chaplin, and "The Kid"

At variance with other largely safe complementary alternative medicines like homeopathy and acupuncture, which only carry the risk of inducing patients to shun effective treatment, herbal remedies are real, albeit impure, drugs and therefore fully capable of producing undesirable consequences if misused. The advantages they offer are uncertain since genuine evidence of efficacy and effectiveness i

Three-Dimensional Design Optimization Of An Anode-Supported SOFC Using FEM

Abstract in UndeterminedSolid oxide fuel cells (SOFCs) are promising as energy producing devices, which at this stage of development will require extensive analysis and benefit from numerical modeling. A 3D model is developed based on the FEM for a single cell planar SOFC design optimization. Ion, electron, heat, gas-phase species and momentum transport equations are implemented and coupled to the

Late Holocene expansion of Siberian dwarf pine (Pinus pumila) in Kamchatka in response to increased snow cover as inferred from lacustrine oxygen-isotope records

Holocene records of cellulose-inferred lake-water delta O-8 were produced from two lake-sediment sequences obtained in central and northern Kamchatka, Russian Far East. The sediment records share similar fluctuations in delta O-8 during the interval of ca. 5000-800 cal yr BP that correspond (inversely) with changes in K+ content of the GISP2 ice-core record from Greenland, a proxy for the relative

Evaluation of Analytical Measures of Map Legibility

The generation of maps in real-time web-services introduces challenges concerning map legibility. As these services lack the important input of a traditional cartographer, analytical measures of the legibility are called for. The aim of this study was to develop such legibility measures, and to evaluate them with the help of expert users. Measures of the amount of information, spatial distribution