526 research outputs found
Group analysis and renormgroup symmetries
An original regular approach to constructing special type symmetries for
boundary value problems, namely renormgroup symmetries, is presented. Different
methods of calculating these symmetries, based on modern group analysis are
described. Application of the approach to boundary value problems is
demonstrated with the help of a simple mathematical model.Comment: 17 pages, RevTeX LATeX file, to appear in Journal of Mathematical
Physic
Calculation of thermal parameters of SiGe microbolometers
The thermal parameters of a SiGe microbolometer were calculated using
numerical modeling. The calculated thermal conduction and thermal response time
are in good agreement with the values found experimentally and range between
2x10 and 7x10 W/K and 1.5 and 4.5 ms, respectively. High sensitivity
of microbolometer is achieved due to optimization of the thermal response time
and thermal conduction by fitting the geometry of supporting heat-removing legs
or by selection of a suitable material providing boundary thermal resistance
higher than 8x10 cmK/W at the SiGe interface.Comment: 11 pages, 6 figure
IMMUNOSUPPRESSION AS A COMPONENT OF MULTIPLE ORGAN DYSFUNCTION SYNDROME FOLLOWING CARDIAC SURGERY
Aim. To defne the role of myeloid-derived suppressor cells in the development of persistent multiple organ dysfunction followed cardiac surgeries with cardiopulmonary bypass.Methods. 40 patients who have undergone cardiac surgery were included in the study. Granulocyte myeloid-derived suppressor cells (G-MDSC) were defned as cells with the HLA-DR– / CD11β+ / CD15+ / CD33+ phenotype, and monocytic MDSC (M-MDSC) as cells with the HLA-DR– / CD11β+ / CD14+ / CD33+ phenotype using flow cytometry. Levels of cytokines, IL-1β, IL-6, TNF-α, and IL-10 were measured with an enzyme immunoassay. All patients were assigned to three groups: Group 1 – patients with the uncomplicated postoperative period (n = 14), Group 2 – patients with non-persistent MODS and its early resolution (n = 16), and Group 3 – patients with persistent MODS at day 7.Results. We observed an increase in M-MDSCs and G-MDSC at day 1 following cardiac surgery. The most pronounced increase was found in monocytic-myeloid derived suppressor cells, i.e. an 8-fold increase in M-MDSCs in all study groups at day 1 after surgery. The number of M-MDSCs remained high in patients with persistent MODS at day 7 after cardiac surgery. Levels of IL-6 and IL-10 increased at day 1 after surgery. IL-6 reached its peak level, signifcantly exceeding baseline levels. By day 7, blood levels of all cytokines have decreased, except IL-10 levels, which remained above the baseline in patients with persistent MODS.Conclusion. An increase in M-MDSCs and elevated serum levels of the anti-inflammatory cytokine IL-10 have been found in patients regardless of the presence or absence of the complications in the early postoperative period after cardiac surgery with cardiopulmonary bypass. Persistent MODS with the SOFA scoring > 5 scores at day 7 after cardiac surgery, is associated with an increase in M-MDSCs and elevated levels of the anti-inflammatory cytokine IL-10, related to higher rate of hospital infections, prolonged intensive care unit stay and higher mortality.Aim. To defne the role of myeloid-derived suppressor cells in the development of persistent multiple organ dysfunction followed cardiac surgeries with cardiopulmonary bypass.Methods. 40 patients who have undergone cardiac surgery were included in the study. Granulocyte myeloid-derived suppressor cells (G-MDSC) were defned as cells with the HLA-DR– / CD11β+ / CD15+ / CD33+ phenotype, and monocytic MDSC (M-MDSC) as cells with the HLA-DR– / CD11β+ / CD14+ / CD33+ phenotype using flow cytometry. Levels of cytokines, IL-1β, IL-6, TNF-α, and IL-10 were measured with an enzyme immunoassay. All patients were assigned to three groups: Group 1 – patients with the uncomplicated postoperative period (n = 14), Group 2 – patients with non-persistent MODS and its early resolution (n = 16), and Group 3 – patients with persistent MODS at day 7.Results. We observed an increase in M-MDSCs and G-MDSC at day 1 following cardiac surgery. The most pronounced increase was found in monocytic-myeloid derived suppressor cells, i.e. an 8-fold increase in M-MDSCs in all study groups at day 1 after surgery. The number of M-MDSCs remained high in patients with persistent MODS at day 7 after cardiac surgery. Levels of IL-6 and IL-10 increased at day 1 after surgery. IL-6 reached its peak level, signifcantly exceeding baseline levels. By day 7, blood levels of all cytokines have decreased, except IL-10 levels, which remained above the baseline in patients with persistent MODS.Conclusion. An increase in M-MDSCs and elevated serum levels of the anti-inflammatory cytokine IL-10 have been found in patients regardless of the presence or absence of the complications in the early postoperative period after cardiac surgery with cardiopulmonary bypass. Persistent MODS with the SOFA scoring > 5 scores at day 7 after cardiac surgery, is associated with an increase in M-MDSCs and elevated levels of the anti-inflammatory cytokine IL-10, related to higher rate of hospital infections, prolonged intensive care unit stay and higher mortality
ABOUT AN OPTIMIZATION OF SURGICAL TACTICS OF PANCREATONECROSIS
An. analysis of treatment of 174 patients with acute pancreatonecrosis with use of low-invasive surgical interventions (laparoscopic and puncture-draining surgery) was realized. It is shown that the efficiency of low-invasive surgery for pancreatonecrosis depends on the spread of pathological process. The use of step-by-step approach with use of low-invasive technologies as a start method greatly improves the results of treatment of patients with pancreatonecrosis. For limited forms of pancreatonecrosis low-invasive surgery is the method of choice, and. this surgical approach plays one of the leading roles in improving of treatment outcomes in the population of patients with pancreatonecrosis
First measurements of spin correlations in the np -> d pi^0 reaction
The transverse spin correlations Axx and Ayy in the np-> d pi^0 reaction have
been measured for the first time in quasi-free kinematics at the COSY-ANKE
facility using a polarised deuteron beam incident on a polarised hydrogen cell
target. The results obtained for neutron energies close to 353 MeV and 600 MeV
are in good agreement with the partial wave analysis of data on the
isospin-related pp-> d pi^+ reaction, though the present results cover also the
small-angle region, which was largely absent from these data
Analysing powers and spin correlations in deuteron-proton charge exchange at 726 MeV
The charge exchange of vector polarised deuterons on a polarised hydrogen
target has been studied in a high statistics experiment at the COSY-ANKE
facility at a deuteron beam energy of Td = 726 MeV. By selecting two fast
protons at low relative energy E_{pp}, the measured analysing powers and spin
correlations are sensitive to interference terms between specific
neutron-proton charge-exchange amplitudes at a neutron kinetic energy of Tn ~
1/2 Td =363 MeV. An impulse approximation calculation, which takes into account
corrections due to the angular distribution in the diproton, describes
reasonably the dependence of the data on both E_{pp} and the momentum transfer.
This lends broad support to the current neutron-proton partial-wave solution
that was used in the estimation
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