TWO-STAGE PROGNOSIS OF POSTOPERATIVE COMPLICATIONS IN PATIENTS WITH ACUTE PERITONITIS

Introduction. Acute peritonitis still remains one of the most severe and threatening abdominal cavity disease. An important component of the treatment of acute peritonitis is the ability to prognose adequately the possibility of postoperative complications, which allows to use appropriate preventive measures. For the case, numerous methods, based on the account of various parameters, are developed. But none of them is fully accepted, and useful. Purpose. To develop an informative scale for postoperative complications predicting. Material and method. The retrospective analysis of outcome of treatment of 169 patients with acute surgical pathology of abdominal organs complicated by various forms of peritonitis, 79 of whom developed postoperative complications results are presented. The dependence of occurrence and severity of complications on the nature of the underlying disease, clinical manifestations of peritonitis before surgery, anthropometric data research, laboratory methods, Mannheim peritonitis index parameters, comorbidity class, age were studied, using the analysis of variance. Results. A scale according to which the prediction of complications is conducted in two stages, was developed. Before the surgery, we estimate the previous risk according to the nature of the underlying disease, clinical manifestations of peritonitis, comorbidity class. According to identified changes, the finalestimation due to the nature of the underlying disease, Mannheim peritonitis index parameters, comorbidity class, stab neutrophil leukocytes number, use of programmedperitoneal cavity sanations is being made during the operation. These indicators provided a certain number of points. Due to this points, patients were referred to several groups: normal group (less than 18), increased (18-25), medium (26-34) and high (more than 35) the risk of complications. Conclusions. The developed scale makes it possible to apply the necessary preventive measures at all stages of treatment, since preoperative preparation

Target-ion source unit ionization efficiency measurement by method of stable ion beam implantation

The ionization efficiency is one of the most important parameters of an on-line used target-ion source system exploited for production of exotic radioactive beams. The ionization efficiency value determination as a characteristic of a target-ion source unit in the stage of its normalizing before on-line use is a very important step in the course of the preparation for an on-line experiment. At the IRIS facility (Petersburg Nuclear Physics Institute, Gatchina) a reliable and rather precise method of the target-ion source unit ionization efficiency measurement by the method of stable beam implantation has been developed. The method worked out exploits an off-line mass-separator for the implantation of the ion beams of selected stable isotopes of different elements into a tantalum foil placed inside the Faraday cup in the focal plane of the mass-separator. The amount of implanted ions has been measured with a high accuracy by the current integrator connected to the Faraday cup. After the implantation of needed amount of the investigated specie, tantalum foil has been implemented into the volume of the target-ion source unit prepared for the on-line utilization at the IRIS on-line separator. For the foil implementation the unit is equipped by a window, which is being closed by a plug after the inserting the tantalum foil with the defined amount of atoms of the measured specimen into the target volume. The first tests with the method used have supplied the ionization efficiency values (9020) % for Rb and (8520) % for Cs in the empty combined target-ion source unit, which was used as a reference one. For the combined target-ion source unit with UC target material inside prepared for on-line experiment the measured value of the ionization efficiency was (52 20) %, that likely can be explained by the carbonization of the inner surface of the target container that brings to the decrease of its work function

Isotope shift and hyperfine structure measurements for 155^{155}Yb by laser ion source technique

The change in the mean square charge radius and electromagnetic moments of the neutron deficient $^{155}$Yb isotope have been determined using resonance ionization spectroscopy in a laser ion source. The data point to an absence of a marked deformation change for Yb isotopes with N=84-86

Secondary neutrons as the main source of neutron-rich fission products in the bombardment of a thick U target by 1 GeV protons

The diffusion-effusion model has been used to analyse the release and yields of Fr and Cs isotopes from uranium carbide targets of very different thicknesses (6.3 and 148 g/cm2) bombarded by a 1 GeV proton beam. Release curves of several isotopes of the same element and production efficiency versus decay half-life are well fitted with the same set of parameters. Comparison of efficiencies for neutron-rich and neutron-deficient Cs isotopes enables separation of the contributions from the primary (p+238U) and secondary (n + 238U) reactions to the production of neutron-rich Cs isotopes. A rather simple calculation of the neutron contribution describes these data fairly well. The FLUKA code describes the primary and secondary-reaction contributions to the Cs isotopes production efficiencies for different targets quite well

Production of Cs and Fr isotopes from a high-density UC targets with different grain dimensions

International audienceA UC target material of 11.3 ± 0.5 g/cm3 uranium density with the grain size of 20 and 5 μm manufactured in a form of pills by the method of powder metallurgy has been tested on-line within the temperature range of 1800–2100 ◦C. The mass of uranium exposed to the beam was 4–7 g. The yields and release rates of Cs and Fr isotopes produced by fission and spallation reactions of 238U by 1 GeV protons have been measured. The yields of Cs and Fr isotopes obtained from the tested target materials have been compared, including yields of very short-lived Fr isotopes with half-lives down to 1 ms. Temperatureresistant materials (porous graphite and tantalum foil) have been used for the internal-container construction, which holds the UC target pills inside a tungsten external container heated by the resistant heating. The fastest release and the highest efficiency for short-lived isotopes have been obtained for the targets with the internal container manufactured from the tantalum foil. Results of on-line tests of a big mass target (730 g of 5 μm grain UC target material) have been discussed

Electron beam-plasma ionizing target for the production of neutron-rich nuclides

The production of neutron rich Ag, In and Sn isotopes from a UC target of high density has been investigate at the IRIS facility. An electron beam-plasma ion source has been used to ionize the species produced