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1.
Rep Prog Phys ; 81(9): 094301, 2018 09.
Article in English | MEDLINE | ID: mdl-29952755

ABSTRACT

The European Strategy Forum on Research Infrastructures (ESFRI) has selected in 2006 a proposal based on ultra-intense laser fields with intensities reaching up to 1022-1023 W cm-2 called 'ELI' for Extreme Light Infrastructure. The construction of a large-scale laser-centred, distributed pan-European research infrastructure, involving beyond the state-of-the-art ultra-short and ultra-intense laser technologies, received the approval for funding in 2011-2012. The three pillars of the ELI facility are being built in Czech Republic, Hungary and Romania. The Romanian pillar is ELI-Nuclear Physics (ELI-NP). The new facility is intended to serve a broad national, European and International science community. Its mission covers scientific research at the frontier of knowledge involving two domains. The first one is laser-driven experiments related to nuclear physics, strong-field quantum electrodynamics and associated vacuum effects. The second is based on a Compton backscattering high-brilliance and intense low-energy gamma beam (<20 MeV), a marriage of laser and accelerator technology which will allow us to investigate nuclear structure and reactions as well as nuclear astrophysics with unprecedented resolution and accuracy. In addition to fundamental themes, a large number of applications with significant societal impact are being developed. The ELI-NP research centre will be located in Magurele near Bucharest, Romania. The project is implemented by 'Horia Hulubei' National Institute for Physics and Nuclear Engineering (IFIN-HH). The project started in January 2013 and the new facility will be fully operational by the end of 2019. After a short introduction to multi-PW lasers and multi-MeV brilliant gamma beam scientific and technical description of the future ELI-NP facility as well as the present status of its implementation of ELI-NP, will be presented. The science and examples of societal applications at reach with these electromagnetic probes with much improved performances provided at this new facility will be discussed with a special focus on day-one experiments and associated novel instrumentation.

2.
Phys Rev Lett ; 118(16): 162502, 2017 Apr 21.
Article in English | MEDLINE | ID: mdl-28474931

ABSTRACT

A search for shape isomers in the ^{66}Ni nucleus was performed, following old suggestions of various mean-field models and recent ones, based on state-of-the-art Monte Carlo shell model (MCSM), all considering ^{66}Ni as the lightest nuclear system with shape isomerism. By employing the two-neutron transfer reaction induced by an ^{18}O beam on a ^{64}Ni target, at the sub-Coulomb barrier energy of 39 MeV, all three lowest-excited 0^{+} states in ^{66}Ni were populated and their γ decay was observed by γ-coincidence technique. The 0^{+} states lifetimes were assessed with the plunger method, yielding for the 0_{2}^{+}, 0_{3}^{+}, and 0_{4}^{+} decay to the 2_{1}^{+} state the B(E2) values of 4.3, 0.1, and 0.2 Weisskopf units (W.u.), respectively. MCSM calculations correctly predict the existence of all three excited 0^{+} states, pointing to the oblate, spherical, and prolate nature of the consecutive excitations. In addition, they account for the hindrance of the E2 decay from the prolate 0_{4}^{+} to the spherical 2_{1}^{+} state, although overestimating its value. This result makes ^{66}Ni a unique nuclear system, apart from ^{236,238}U, in which a retarded γ transition from a 0^{+} deformed state to a spherical configuration is observed, resembling a shape-isomerlike behavior.

3.
Food Sci Biotechnol ; 25(Suppl 1): 157-161, 2016.
Article in English | MEDLINE | ID: mdl-30263501

ABSTRACT

Food poisoning outbreaks frequently occur in many countries resulting in economic loss. A formula for calculation of economic loss due to food poisoning outbreaks in Indonesia was developed. Estimation of the loss was developed based on experiences in several countries. Related data were also collected from local health facilities, food industry officials, and other sources to improve the accuracy of the formula. Calculation of the economic loss was performed based on cases of food poisoning outbreaks recorded in 2013. Economic loss was estimated based on direct health-care costs, direct non-health-care costs, and indirect non-health-care costs. The economic loss of food poisoning outbreaks in Indonesia in 2013 was approximately US$ 78 million. The high-cost of economic loss due to food poisoning outbreaks suggests a need for additional and serious efforts for controlling all aspects of food safety.

4.
J Radiol Prot ; 35(2): 285-95, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25826271

ABSTRACT

Low energy heavy charged particle accelerators are generators of ionizing radiation, due to the ion beam interactions into the machine components, targets and surrounding materials. Nowadays there are available computational tools allowing realistic estimates of radiation doses and residual activity of the activated components. These evaluations are further used to design the radiological safety system required by licensing and operation of the equipment.This paper presents results of measurements and numerical simulations of the radiation doses and residual activity, at the recently commissioned Bucharest 3 MV Cockcroft-Walton type Tandetron accelerator presently used mainly for Ion Beam Analysis (IBA) research.


Subject(s)
Models, Statistical , Particle Accelerators/instrumentation , Radiation Exposure/analysis , Radiation Protection/instrumentation , Radiation Protection/methods , Radiometry/methods , Computer Simulation , Equipment Design , Equipment Failure Analysis , Hungary , Radiation Dosage , Radiometry/instrumentation , Scattering, Radiation
5.
Appl Radiat Isot ; 70(7): 1337-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22154387

ABSTRACT

We report on a gamma-ray coincidence analysis using a mixed array of hyperpure germanium and cerium-doped lanthanum tri-bromide (LaBr3:Ce) scintillation detectors to study nuclear electromagnetic transition rates in the pico-to-nanosecond time regime in 33,34P and 33S following fusion-evaporation reactions between an 18O beam and an isotopically enriched 18O implanted tantalum target. Energies from decay gamma-rays associated with the reaction residues were measured in event-by-event coincidence mode, with the measured time difference information between the pairs of gamma-rays in each event also recorded using the ultra-fast coincidence timing technique. The experiment used the good full-energy peak resolution of the LaBr3:Ce detectors coupled with their excellent timing responses in order to determine the excited state lifetime associated with the lowest lying, cross-shell, Iπ=4- "intruder" state previously reported in the N=19 isotone 34P. The extracted lifetime is consistent with a mainly single-particle M2 multipolarity associated with a f7/2→d5/2 single particle transition.

6.
Rom J Morphol Embryol ; 52(1 Suppl): 249-62, 2011.
Article in English | MEDLINE | ID: mdl-21424062

ABSTRACT

INTRODUCTION: Endoscopic evaluation is one of the most important explorations in the diagnosis of gastric cancer, increasing its value by adding biopsy sampling and histopathologic examination, especially in early forms of gastric malignant proliferations. The aim of this study was to evaluate some descriptive parameters of macroscopic and microscopic aspects of gastric carcinomas defined with the help of endoscopic investigation and gastric biopsies sampled during endoscopic examination, and their correlation with patient survival. MATERIALS AND METHODS: The study was performed on a group of 119 patients diagnosed with gastric carcinoma. The study material was represented by: tissue fragments obtained by endoscopic biopsy, clinical observation charts, histopathologic diagnosis records, ledgers for records of endoscopic investigation, and endoscopic images recorded for each patient. Biopsies were taken preferentially from areas with the highest risk of malignancy. Tumor fragments were subjected to conventional histological processing techniques (fixation and inclusion in paraffin) and then were stained with HIM. The study included two chapters: the imagistic study and the pathologic study. The parameters assessed were: the site of the lesion within the stomach, the endoscope macroscopic appearance, the microscopic appearance of the endoscope biopsy sample, and the survival, followed up until 48 months. RESULTS: The most frequently observed macroscopic aspect was the fungating one, in more than two thirds of all cases, followed by the infiltrating one, but all with a poor survival - about 25-30% at 24 months. The most frequent location was the antro-pyloric region, with the highest survival rate of 25% at 24 months, followed by the gastric corpus and the lesser curvature. Most of the tumors were restricted to a single segment of the stomach. The most frequent microscopic aspect was the tubular one (75% of all cases) with its poorly differentiated variant (39 of the 91 cases). The 24 months survival was under 50% for all morphological types of carcinoma, with the lowest ones in the tubular and mucinous types (around 25%). The secretory pattern was identified on biopsy samples stained with HE in only 15% of the cases, and did not influence the survival of the patients. CONCLUSIONS: The combined histologic and endoscopic morphologic investigation allowed the shaping of an accurate morphologic and prognostic preoperative profile in gastric carcinomas.


Subject(s)
Gastroscopy/methods , Stomach Neoplasms/diagnosis , Stomach Neoplasms/pathology , Biopsy , Cell Differentiation , Humans , Recurrence , Stomach/pathology , Stomach Neoplasms/metabolism , World Health Organization
7.
Rom J Morphol Embryol ; 52(1 Suppl): 349-61, 2011.
Article in English | MEDLINE | ID: mdl-21424074

ABSTRACT

INTRODUCTION: Imagistic examinations have an essential role in the assessment of gastric cancer both in earlier and advanced stages. Among these, endoscopic ultrasound (EUS) especially contributes to the diagnosis by direct visualization of the tumor and to the staging and prognosis assessment through the evaluation of the gastric wall and regional lymph nodes. Computer tomography (CT) examination also has an important role, especially in advanced stages, in the assessment of the prognosis, contributing to TNM staging. The aim of this study is a comparative assessment of tumor invasion degree by these two imagistic methods and the correlation of the imagistic diagnosis with histopathologic assessment results on surgical specimens. MATERIALS AND METHODS: The basis of the study was represented by a group of 38 patients with gastric carcinoma investigated both by endoscopic ultrasound and computer tomography from which 15 cases with surgical excision of the tumor followed by microscopic examination were selected. Studied material was represented by: patients' medical charts, registers for ultrasound endoscopy and CT investigation, endoscopic and CT images, surgical excision samples and pathology reports. Tumor fragments were processed by classical histological techniques (fixation and paraffin wax embedding) and staining (HE). RESULTS: Comparing the CT examination with ultrasound endoscopy results showed that CT examination overestimated the invasion grade of the gastric wall (T) but accurately defined the grade of lymph node invasion (N) and metastases (M). Comparing the results of ultrasound endoscopic examination with those from histopathological examination showed that the first method underestimated the grade of invasion of the gastric wall (T) while the latter correctly defined the grade of lymph node invasion (N) and metastases (M). Comparing CT examination results with histopathological ones showed that CT overestimated both the grade of invasion of the gastric wall (T), lymph node invasion (N) and metastases (M). CONCLUSIONS: In the preoperative assessment of the invasion stage of gastric carcinoma (TNM), ultrasound endoscopy is the elective imagistic investigation for predicting the grade of invasion of the gastric wall while CT examination is a more accurate assessment of lymph node extension and metastases, the precise definition of invasion stage being only the result of histopathological examination on surgical specimens.


Subject(s)
Stomach Neoplasms/diagnostic imaging , Stomach Neoplasms/pathology , Adenocarcinoma/pathology , Aged , Endoscopy , Humans , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasm Staging , Stomach Neoplasms/surgery , Tomography, X-Ray Computed , Ultrasonography
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