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Biomedical subjects

L Popescu

Publications and source records attributed to L Popescu.

At least 19 recordsLinked to original sources
PubMed2006

Gamow-Teller strengths in the A = 14 multiplet: a challenge to the shell model.

A new experimental approach to the famous problem of the anomalously slow Gamow-Teller (GT) transitions in the beta decay of the A=14 multiplet is presented. The GT strength distributions to excited states in 14C and 14O were studied in high-resolution (d,2He) and (3He,t) charge-exchange reactions on 14N. No-core shell-model calculations capable of reproducing the suppression of the beta decays predict a selective excitation of Jpi=2+ states. The experimental confirmation represents a validation of the assumptions about the underlying structure of the 14N ground state wave function. However, the fragmentation of the GT strength over three 2+ final states remains a fundamental issue not explained by the present no-core shell model using a 6homega model space, suggesting possibly the need to include cluster structure in these light nuclei in a consistent way.

Journal Article↗
PubMed2005

Gamow-teller strengths in proton-rich exotic nuclei deduced in the combined analysis of mirror transitions.

Isospin symmetry is expected for the T(z)=+/-1-->0 isobaric analogous transitions in isobars with mass number A, where T(z) is the z component of isospin T. Assuming this symmetry, strengths of analogous Gamow-Teller (GT) transitions within A = 50 isobars were determined from a high energy-resolution study at 0 degrees in combination with the decay Q value and lifetime from the beta decay. This method can be applied to other pf-shell nuclei and can be used to study GT strengths of astrophysical interest.

Journal Article↗
PubMed2005

Changes of the nutrient loads of the Danube since the late eighties: An analysis based on long term changes along the whole Danube River and its main tributaries.

The Danube nutrient loads are affected by human impacts mainly from agriculture and wastewater discharges. Knowledge about the Danube nutrient loads and the changes of these loads over time is essential for understanding the changes within the ecosystem of the Black Sea, induced by these loads. The paper shows the long term changes of the nutrient load along the Danube estimated by measurements from different countries and institutions. The results show large differences between Dissolved Inorganic Nitrogen (DIN) and Total Phosphorus (TP). For TP, the Danube River loads show a strong decrease since 1988-1992, especially in the Middle and Lower basin. This change is probably partly connected to the dramatic economic changes in the Middle and Eastern European countries following the collapse of the communist system. The DIN load does not show a decreasing trend in the last decade. The data indicate that there may be a decreasing trend in the anthropogenic emissions, but that such a trend is counteracted by a significantly increasing trend of the Danube discharge in the last decade. The accuracy of the available data is analysed in the paper as well.

Environmental Monitoring↗
PubMed1995

Early re-feeding in the management of acute diarrhoea in infants of 0-1 year of age.

We compared early versus late re-feeding in the management of acute diarrhoea in the first year of life. In the study group (73 groups) breast feeding was resumed or early re-feeding was performed in non-breast-fed infants, so that the feeding regimen used prior to the onset of the disease was reached within 2-3 days. In the control group (49 patients) late re-feeding was performed so that the infants returned to their original feeding pattern after 4-6 days. there were no significant differences between the two groups in the number of stools and stool output per day, or in the duration of the disease. No weight gain or loss during the diet was noted more frequently in the late re-feeding group (67.2% versus 2.3.4%). This study confirms the favourable effect on body weight of early re-feeding in the management of acute diarrhoea.

Acute Disease↗
PubMed1975

Conservative treatment of cervico-facial suppurations.

The author prefers conservative treatment of suppurations in the cervico-facial area. It consists of evacuation of pus by puncture and simultaneous instillation of antibiotics. The technique for superficial and deep infections is described. On the basis of 470 cases treated the method is considered very efficient.

Face↗
PubMedDate not supplied

[Our experience in the conservative surgical treatment of coxarthrosis].

The authors present the substantiation of the use of conservative treatment in a series of 163 patients with coxarthrosis operated upon between 1983 and 1990. In 135 of these patients various types of osteotomies were performed: Pauwels valgisation or varus femoral osteotomy (42 cases), McMurray displacement osteotomy (41 cases), varus and displacement osteotomy (19 cases) and Chiari pelvic osteotomy (33 cases). In the remainder of 28 patients tenotomies and hip denervations were performed. The postoperative results, estimated by a strict clinico-radiological survey revealed a marked clinical improvement and radiographically a restoration of joint congruence in about 80% of the cases.

Hip Dislocation↗
PubMedDate not supplied

In vitro effects of pulsed near-ultraviolet laser exposure on human larynx carcinoma cells.

Effects of pulsed near-ultraviolet laser beam on structural characteristics and macromolecular synthesis of carcinoma HEp2 cells were investigated. Laser irradiation damage induced in these eukaryotic cells could be characterized by two development stages: a) a reversible stage with minor morphological damages (1.5 kJ/m2) and 2) an irreversible one, at higher fluences, characterized by cellular membrane damage, necrobiosis and cells detachment from the substrate (4.5 kJ/m2). A. Studies performed referring to macromolecular syntheses of low laser fluences (1.5 kJ/m2)--irradiated HEp2 cells showed the following aspects: a) syntheses inhibiton phase in the first cycles of cellular replication and b) syntheses stimulation phases in the following cycle with total repair of laser-induced molecular lesions. B. At high laser fluences (3-4.5 kJ/m2), metabolic lesions repair was partially or totally blocked after prolonged culturing at 37 degrees C. Ths paper suggests some mechanisms of laser action on macromolecular synthesis and correlates them with morphological changes induced by laser exposure of carcinoma cells.

Carcinoma↗
PubMedDate not supplied

[The Rubinstein-Taybi syndrome].

The paper reports on the case of an infant, diagnosed at 4 months, with Rubinstein-Taybi's syndrome. The main clinical manifestations of the syndrome, that allowed the case diagnosis, are presented. A series of succinct data on the syndrome and also the pathogenic hypotheses are reviewed.

Humans↗
PubMedDate not supplied

The continuous decrease in the number of SSPE annual cases ten years after compulsory anti-measles immunization.

The record of SSPE cases diagnosed immunochemically and serologically in our laboratory, standing for about 60% of the total new cases reported in our country, shows a significant decrease in the incidence in 1988-89 (from 5.21 new cases per year per million total population in 1987 to 1.82 cases in 1988). In 85% of the patients, SSPE onset occurred at the age of 10 years or more, suggesting the possibility of a primary measles infection before anti-measles immunization became compulsory. High serum and CSF anti-measles antibody titres in recently diagnosed patients show subclinical long-term courses. Further serologic tests for viruses inducing persistent infections (herpes viruses, AgHBs and HIV) do not show any difference when compared to a control group excepting an increased incidence of anti-cytomegalic titres.

Age Factors↗
PubMedDate not supplied

[The mechanisms of persistent measles virus infection in HEp-2 cells].

Persistent infection with Edmonston strain of measles virus was established in a highly susceptible clone of HEp-2 cells. The morphological and cytogenic aspects of persistent infection are presented. Carriage of measles virus in cells persistently infected is marked by important differences between standard Edmonston strain and virus stocks isolated from time to time from the carrier state. It is especially significant that cell fusion capacity decreased in amount concordant with the drop in the yield of infectious virus. Addition of UV inactivated Sendai virus, trypsin treatment or incubation at suboptimal temperatures precipitate the cytocidal effect of measles virus. Some clinical implications of reactivation of the lytic cycle in the carrier state are suggested.

Cell Line↗