Search results for " Axis"

Real and Complex Singularities

2016

In this paper a Minkowski analogue of the Euclidean medial axis of a closed and smooth plane curve is introduced. Its generic local configurations are studied and the types of shocks that occur on these are also determined.

INTEGRAL/SPI ground calibration

2003

Three calibration campaigns of the spectrometer SPI have been performed before launch in order to determine the instrument characteristics, such as the effective detection area, the spectral resolution and the angular resolution. Absolute determination of the effective area has been obtained from simulations and measurements. At 1 MeV, the effective area is 65 cm^2 for a point source on the optical axis, the spectral resolution ~2.3 keV. The angular resolution is better than 2.5 deg and the source separation capability about 1 deg. Some temperature dependant parameters will require permanent in-flight calibration.

Right ventricular diastolic function in post-surgical Tetralogy of Fallot patients: A pilot study to make a comparison between echocardiography and c…

2021

Background: right ventricular (RV) systolic dysfunction is associated with poor outcomes in Tetralogy of Fallot (ToF) patients. Conversely, the influence of diastolic dysfunction in this setting is poorly known. In addition, evaluation of RV diastolic function by cardiac MRI is rarely performed.Materials and methods: twenty-four surgically treated ToF patients were enrolled in the study (54% males; median age at study: 28 (18–50) years; median age at surgery: 1.9 (0.4–8.2) years. They were studied by echocardiography to assess RV diastolic function in terms of traditional and TDI-derived parameters. At cardiac MRI, RV diastolic function was assessed by using phase-contrast analysis of flow …

Improved Assessment of Pathological Regurgitation in Patients with Prosthetic Heart Valves by Multiplane Transesophageal Echocardiography

1997

The aim of this study was to evaluate the diagnostic increment of individually optimized axes in the assessment of pathological prosthetic valve regurgitation. Forty-two patients with pathologically regurgitant prostheses in the aortic (n = 21), mitral (n = 15), and tricuspid (n = 6) positions were examined by multiplane transesophageal echocardiography. The investigation was performed utilizing the transverse axis first, the longitudinal axis second, and the intermediate axes afterwards. The presence of regurgitation, the differentiation between trans- and perivalvular origin, and the localization of perivalvular leakages at the sewing ring were evaluated. Findings in the biplane and inter…

An innovative mechanical converter for sea wave application

2017

This paper describes an innovative mechanical converter, usable in sea wave energy sector. This system transforms a variable bidirectional linear motion into a unidirectional rotary motion.

Fitted dosimetric parameters of high dose-rate 192Ir sources according to the AAPM TG43 formalism

2001

The purpose of this study is to find fitted functional forms to the anisotropy function, F(r,θ), and the radial dose function, g(r), in order to characterize dose-rate distributions around all the high-intensity 192 Ir sources currently in use. Dosimetry data are at present available as tables for: the microSelectron HDR (“classic” and “new” design models), the PDR source, and the VariSource HDR source, expressed in terms of the AAPM Task Group No. 43 recommendations. There is only one paper out which introduces a functional form to fit the anisotropy function, but only for symmetric sources with respect to the transverse axis. However, dosimetric data of the HDR and PDR sources mentioned a…

Molecular dynamics in low-molar and polymeric ferroelectric liquid crystals

1991

Broadband dielectric spectroscopy covering the frequency range from 10−1 Hz to 109 Hz was employed to study the molecular dynamics in low-molar and polymeric ferrroelectric liquid crystals. At frequencies below 106 Hz the ferroelectric modes, soft and Goldstone mode are observed. In the frequency regime from 106 Hz to 109 Hz a fast relaxation process is found, which is assigned to the hindered rotation of the mesogens around their long molecular axis. It turns out that the molecular dynamics is not principally different between low-molar and polymeric systems.

2021

Four drugs are currently approved for the treatment of Alzheimer’s disease (AD) by the FDA. Three of these drugs—donepezil, rivastigmine, and galantamine—belong to the class of acetylcholine esterase inhibitors. Memantine, a NMDA receptor antagonist, represents the fourth and a combination of donepezil and memantine the fifth treatment option. Recently, the gut and its habitants, its microbiome, came into focus of AD research and added another important factor to therapeutic considerations. While the first data provide evidence that AD patients might carry an altered microbiome, the influence of administered drugs on gut properties and commensals have been largely ignored so far. However, t…

Die feinstruktur der fl�igelschuppen einiger Lycaeniden (Insecta, Lepidoptera)

1970

Green, blue and violet colours of Lycaenidae examined by us — with the exception of Rapala arata (Theclinae) — are due to iridescent scales which are arranged before a dark background. The iridescent scales are constructed according to the Urania-type and may be diverted from pigmented scales by laying in equidistant lamellae and little cuticular bars, which maintain the distance between the lamellae. The ribs in the longitudinal axis of the scales contain lamellae and bars only in the Plebejinae, in Lycaeninae and Theclinae they are small and sit on the plain upperside of the scale with a narrow base.

Suppression of nodal expression in prospective dorsal cells of the early sea urchin embryo by the hbox12 homeodomain regulator

2014

Dorsal/Ventral (DV) axis formation in the sea urchin embryo depends upon the expression of nodal on the ventral side, which behaves as a DV organizing centre. However, only fuzzy clues are known as to the early symmetry-breaking steps that lead to the positioning of such an organizer. An extremely interesting candidate for this role is the hbox12 homeobox-containing gene. In Paracentrotus lividus, hbox12 expression is antecedent and complementary with respect to that of nodal, being confined in prospective dorsal cells. We show that ectopic expression of Hbox12 provokes DV abnormalities and attenuates nodal as well as nodal-dependent gene transcription. By blastomere transplantation, we als…