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Papers by Marius Stefanescu

Fusion Engineering and Design, 2010

The Cernavoda Nuclear Power Plant is the biggest operational source of tritium, in Europe and one... more The Cernavoda Nuclear Power Plant is the biggest operational source of tritium, in Europe and one of the most important in the world. The recovery of tritium from the moderator of operating Candu reactors and from the reactors to operate, represents a good opportunity for Romania to be involved in international collaboration programs in the field of nuclear fusion.

Journal of Biosciences, 1999

Journal of Clinical Pathology, 1972

An investigation on human peripheral blood lymphocyte chromosomes in chronic active hepatitis was... more An investigation on human peripheral blood lymphocyte chromosomes in chronic active hepatitis was carried out. A higher percentage of chromatid and chromosome lesions was recorded in all patients studied as compared with control groups-normal individuals, healthy subjects who had suffered from acute viral hepatitis, patients with alcoholic liver disease, and patients with mechanical jaundice due to cancer. The possible origin of these abnormalities is discussed.

Romanian Journal of Legal Medicine, 2009

Physics in Medicine and Biology, 2007

In present-day medical practice it is often necessary to nonrigidly align image data. Current reg... more In present-day medical practice it is often necessary to nonrigidly align image data. Current registration algorithms do not generally take the characteristics of tissue into account. Consequently, rigid tissue, such as bone, can be deformed elastically, growth of tumours may be concealed, and contrast-enhanced structures may be reduced in volume. We propose a method to locally adapt the deformation field at structures that must be kept rigid, using a tissue-dependent filtering technique. This adaptive filtering of the deformation field results in locally linear transformations without scaling or shearing. The degree of filtering is related to tissue stiffness: more filtering is applied at stiff tissue locations, less at parts of the image containing nonrigid tissue. The tissue-dependent filter is incorporated in a commonly used registration algorithm, using mutual information as a similarity measure and cubic B-splines to model the deformation field. The new registration algorithm is compared with this popular method. Evaluation of the proposed tissue-dependent filtering is performed on 3D computed tomography (CT) data of the thorax and on 2D digital subtraction angiography (DSA) images. The results show that tissue-dependent filtering of the deformation field leads to improved registration results: tumour volumes and vessel widths are preserved rather than affected.

Studia Geophysica Et Geodaetica, 1978

Using heat flow and heat generation measurements together with deep seismic sounding and gravity ... more Using heat flow and heat generation measurements together with deep seismic sounding and gravity data, a reasonable geothermal model has been constructed for the Romanian Carpathian Bend. At the level of the MOHO discontinuity the calculated temperatures exhibit conspicuous differences between inner and outer border of the Carpathian Bend and a horizontal gradient of 200–300 °C/100 km in the region is not to be excluded.

Renewable Energy, 2008

Currently, hydrogen may be stored as a compressed gas or as cryogenic liquid. Neither method appe... more Currently, hydrogen may be stored as a compressed gas or as cryogenic liquid. Neither method appears to be practical for many applications in which hydrogen use would otherwise be attractive. For example, gaseous storage of stationary fuel is not feasible because of the large volume or weight of the storage vessels. Liquid hydrogen could be used extensively but the liquefaction

Abstract The research project aims to analyse the influence of the natural, economic and social s... more Abstract The research project aims to analyse the influence of the natural, economic and social shocks on the accomplishment of the objectives of sustainable development at the microeconomic level. The implementation of the proposals and solutions delivered by the ...

The paper presents the manufacturing and the characterization of two novel devices on GaN/Si. The... more The paper presents the manufacturing and the characterization of two novel devices on GaN/Si. The first device is a SAW structure for the GHz frequency range manufactured using nanolithografic techniques on GaN. Fingers and intedigits spacing 300nm wide have been successful developed in a single metal PMMA layer. An operating frequency close to 4 GHz has been obtained. For the

Experimental Cell Research, 1972

Human peripheral blood lymphocyte cultures were irradiated with a dose of X-rays split in two equ... more Human peripheral blood lymphocyte cultures were irradiated with a dose of X-rays split in two equal fractions. The first fraction of dose was given shortly after culture initiation and the second one at 0, 2, 4, 18, 20, 22 and 24 h thereafter. Dicentric and ring chromosomes were scored at 54 h of cultivation. The aberration yields were essentially the same regardless of whether the radiation was given in a single burst or in two fractions separated by intervals of up to 20 h. The results unexpectedly revealed that no rejoining took place during this period. A drop in aberration yield occurred when the interval between exposures increased to 24 h, suggesting that at this time the system responsible for the rejoining of broken chromosome ends becomes operative. It was also noticed that no rejoining took place in small non-stimulated lymphocytes incubated at 37°C for 6 h prior to cultivation. These findings may explain the production of two-hit aberrations in peripheral blood lymphocytes of persons chronically exposed to small doses and very small dose rates of ionizing radiations.