Aims
Availability of normative reference values for cardiac chamber quantitation is a prerequisite for accurate clinical application of echocardiography. In this study, we report normal reference ...ranges for cardiac chambers size obtained in a large group of healthy volunteers accounting for gender and age. Echocardiographic data were acquired using state-of-the-art cardiac ultrasound equipment following chamber quantitation protocols approved by the European Association of Cardiovascular Imaging.
Methods
A total of 734 (mean age: 45.8 ± 13.3 years) healthy volunteers (320 men and 414 women) were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. A comprehensive echocardiographic examination was performed on all subjects following pre-defined protocols. There were no gender differences in age or cholesterol levels. Compared with men, women had significantly smaller body surface areas, and lower blood pressure. Quality of echocardiographic data sets was good to excellent in the majority of patients. Upper and lower reference limits were higher in men than in women. The reference values varied with age. These age-related changes persisted for most parameters after normalization for the body surface area.
Conclusion
The NORRE study provides useful two-dimensional echocardiographic reference ranges for cardiac chamber quantification. These data highlight the need for body size normalization that should be performed together with age-and gender-specific assessment for the most echocardiographic parameters.
Microwave attenuation measurements at 25 and 38 GHz made on a 2.3-km microwave link are employed to estimate drop size distributions (DSD), rainfall rate, and rainfall accumulation. A theoretical ...model for the propagation of microwaves in a link system sets forth the basis for the development of a dual-wavelength analytical technique to invert two parameters of a path-average gamma DSD. The DSDs obtained from the technique are evaluated in conjunction with point measurements performed with a 2-D video disdrometer. Additionally, the DSDs yield path-average rainfall rates and rainfall accumulation which are compared with path-average measurements from a network of optical and tipping bucket rain gauges located beneath the link path, and with estimates based on empirical power law relations.
The strain-life approach is a powerful tool for the assessment of steel constructions experiencing low cycle as well as high cycle fatigue. However, among the various modifications and variations of ...the original concept, the decision to choose a proper one is challenging. Especially since common guidelines do not provide clear recommendations or do not cover the strain-life approach at all. In this contribution, we compared widely accepted versions as well as somewhat newer ideas of the approach regarding the determination of local strains, mean stress correction or strength hypothesis in an extensive numerical study including three geometries with different sharp notches. We essentially emphasized the incorporation of plastic material behavior directly in the finite-element (FE) calculation using a plastic material law. There are partly similar investigations, but they focus exclusively on elastic calculations with subsequent plasticity corrections. Based on the results, recommendations for the application of the approach are given and aspects worth focusing on in further research are suggested. Additionally, a local and global sensitivity analysis of the material parameters was performed for both, that is elastic calculations combined with a plasticity correction as well as plastic FE-computations. The performed analysis identifies the fatigue strength exponent and the fatigue ductility exponent as the parameters most influencing the estimated fatigue life, given their maximum correlation coefficients of 0.56 and 0.91 respectively. The observed results seem to critically assess current approximation methods of strain-life material properties, since these two parameters are often assumed to be constant values for a range of steel grades.
•Influence of different methods concerning plasticity, mean stress and strength hypothesis on the fatigue lives is shown•Sensitivity analysis concerning material properties of the strain-life approach•Effects of different approaches to incorporate plasticity on the size of the highly stressed area are discussed•Stress and strain distributions near the notch in depending relation of plasticity correction methods are compared•Fundamental understanding is provided regarding influencing factors on the approximated fatigue life
In this work, x-ray multiple diffraction has been used as a three-dimensional high-resolution probe to study the Fe+ ion implantation process in Si(0 0 1). The semiconducting *b-FeSi2 ...crystallographic phase has been synthesized by Fe ion co-implantation in Si(0 0 1) followed by ion-beam-induced epitaxial crystallization (IBIEC) and thermal treatment. This phase was clearly detected by the conventional techniques, micro-Raman scattering spectroscopy, transmission electron microscopy (TEM) and grazing incidence x-ray diffraction. Synchrotron radiation rocking curves (*w-scans) and mapping of the Bragg surface diffraction (BSD) of the Si matrix, as-implanted, after the IBIEC process and thermally treated, have enabled the detection of co-implanted regions formation that present distinct lattices in comparison with the matrix one clearly observed by TEM. Also, the compressive strain of both regions in depth by rocking curve and in-plane has been determined by using BSD, which is one order of magnitude smaller.
Correlations between morphological and genetic data provide evidence to delineate species or evolutionarily significant units, which then become the units to conserve in management plans. Here, we ...examine the distribution and genetic differentiation of two morphotypes of short‐finned pilot whale (Globicephala macrorhynchus) in the Pacific Ocean. Mitochondrial control region sequences from 333 samples were combined with 152 previously published sequences to describe genetic variability globally and population structure in the Pacific. Although genetic variability is low, we found strong differentiation at both broad and local levels across the Pacific. Based on genetics, two types are distributed throughout the Pacific, one predominantly in the eastern Pacific and the other in the western and central Pacific. In the eastern Pacific Ocean, no correlation was found between distribution and sea surface temperature. The two types have broad latitudinal ranges, suggesting their distributions are likely driven by more complex factors, such as prey distribution, rather than sea surface temperature.
Improved pulse shape discrimination in EJ-301 liquid scintillators Lang, R.F.; Masson, D.; Pienaar, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
06/2017, Letnik:
856
Journal Article
Recenzirano
Odprti dostop
Digital pulse shape discrimination has become readily available to distinguish nuclear recoil and electronic recoil events in scintillation detectors. We evaluate digital implementations of pulse ...shape discrimination algorithms discussed in the literature, namely the Charge Comparison Method, Pulse-Gradient Analysis, Fourier Series and Standard Event Fitting. In addition, we present a novel algorithm based on a Laplace Transform. Instead of comparing the performance of these algorithms based on a single Figure of Merit, we evaluate them as a function of recoil energy. Specifically, using commercial EJ-301 liquid scintillators, we examined both the resulting acceptance of nuclear recoils at a given rejection level of electronic recoils, as well as the purity of the selected nuclear recoil event samples. We find that both a Standard Event fit and a Laplace Transform can be used to significantly improve the discrimination capabilities over the whole considered energy range of 0−800keVee. Furthermore, we show that the Charge Comparison Method performs poorly in accurately identifying nuclear recoils.
Learning Objectives
After completing this course, the reader will be able to:
Identify which advanced breast cancer patients in the three subsets studied (with nonvisceral metastases, with visceral ...metastases without liver involvement, and with liver metastases) responded most favorably to first‐line therapy.
Describe the limitations of first‐line treatment in the three subsets of patients with advanced breast cancer.
Explain how KPS assessment correlates with overall survival in patients with advanced breast cancer with different sites of metastatic lesions.
Access and take the CME test online and receive 1 hour of AMA PRA category 1 credit at CME.TheOncologist.com
Purpose. The letrozole study 025 is a large (n = 907), international, double‐blind, randomized, phase III trial in postmenopausal women with advanced breast cancer. This subanalysis compares the efficacies of letrozole and tamoxifen as first‐line therapy in postmenopausual women with advanced breast cancer according to site of metastatic lesions and Karnofsky Performance Status (KPS).
Materials and Methods. Nine hundred seven patients with advanced breast cancer were randomly assigned to once‐daily oral letrozole (2.5 mg; Femara®; Novartis Pharma AG; Basel, Switzerland) or tamoxifen (20 mg; Tamofen®; Leiras OY; Turku, Finland). Time to progression (TTP) was estimated using the Kaplan‐Meier product‐limit method. Treatments were compared by Cox proportional hazards regression models.
Results. Letrozole treatment significantly prolonged TTP in all subsets of patients: those with nonvisceral metastases, those with visceral metastases without liver involvement, and those with liver metastases. The reduction in risk of progression ranged from 25%, for patients with nonvisceral metastases, to 36%, for patients with liver metastases. The distributions of baseline KPS scores for both treatment groups were similar (57% had KPS scores ≥90). Time to worsening of 20 points or more in KPS score was significantly longer with letrozole than with tamoxifen, but modest numbers of patients experienced such deterioration (letrozole, 20%, tamoxifen, 22%, in patients without visceral metastases; 23%–24% in patients with liver metastases; and letrozole, 14%, tamoxifen, 30%, in patients with visceral metastases without liver involvement).
Conclusion. These data demonstrate the consistent superiority of letrozole over tamoxifen and support the use of letrozole as a new standard of endocrine therapy in postmenopausal women with advanced breast cancer.
We investigate depletion interactions near a wall caused by polydisperse silica-coated gibbsite platelets, using total internal reflection fluorescence microscopy (TIRF) to characterize the ...sphere-wall interaction potential. As no theoretical model for polydisperse platelets exists, we extend a model for monodisperse depletant cylinders by assuming negligible thickness and averaging over the disc size distribution, finding nearly perfect matching with experimental data. The resulting averaged depletion potentials have, as predicted by the extended model, the same depth as monodisperse potentials, but differ in range and shape according to the size distribution. We compare mean particle sizes and standard deviations derived by TIRF with results from TEM measurements.
The CRESST experiment monitors 300
g CaWO
4 crystals as targets for particle interactions in an ultra low background environment. In this paper, we analyze the background spectra that are recorded by ...three detectors over many weeks of data taking. Understanding these spectra is mandatory if one wants to further reduce the background level, and allows us to cross-check the calibration of the detectors. We identify a variety of sources, such as intrinsic contaminations due to primordial radioisotopes and cosmogenic activation of the target material. In particular, we detect a 3.6
keV X-ray line from the decay of
41Ca with an activity of
(
26
±
4
)
μ
Bq
, corresponding to a ratio
41
Ca
/
40
Ca
=
(
2.2
±
0.3
)
×
10
-
16
.
The XENON1T experiment searches for dark matter particles through their scattering off xenon atoms in a 2 metric ton liquid xenon target. The detector is a dual-phase time projection chamber, which ...measures simultaneously the scintillation and ionization signals produced by interactions in target volume, to reconstruct energy and position, as well as the type of the interaction. The background rate in the central volume of XENON1T detector is the lowest achieved so far with a liquid xenon-based direct detection experiment. In this work we describe the response model of the detector, the background and signal models, and the statistical inference procedures used in the dark matter searches with a 1 metric ton×year exposure of XENON1T data, that leads to the best limit to date on WIMP-nucleon spin-independent elastic scatter cross section for WIMP masses above 6 GeV/c2.
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