164 research outputs found
Приветствие Л. М. Рошаля
Greeting from L.M. RoshalПриветствие Л. М. Рошал
X-ray prerequisites for transverse platypodia
Background. Static deformation of the forefoot is one of the common orthopedic pathologies, most often found in women. X-ray index of the first metatarsocuneiform joint (M1C1) is important during preoperative planning to determine the surgeon volume for surgical treatment of static forefoot deformity.Objective. To determine the radiometric prerequisites for the development of transverse platypodia depending on the structure of the first metatarsopharyngeal joint to improve the results of surgical treatment of patients.Material and Methods. From 2015 to 2017, a retrospective study of X-rays of 236 feet (118 patients) performed in a standard dorsoplant projection at rest and with a functional load was carried out.Results. The analysis of the obtained X-ray patterns revealed a direct dependence between the inclination of the articular surface of the medial sphenoid bone and angles of inclination of the articular surface of the base of the first phalanx of the first finger, the head of the first metatarsal bone (PASA), the intertarsal angle (M1M2) and the deflection angle of the first finger (M1P1).Conclusion. Further study of the dependence of the degree of transverse platypodia to the angle of inclination of the articular surface of the medial sphenoid bone and the use of the angle P1C1 as a prognostic indicator, in our opinion, will improve the quality of preoperative planning of surgical treatment of patients with transverse platypodia to reduce the risk of relapse
Hydrodynamic modeling of deconfinement phase transition in heavy-ion collisions at NICA-FAIR energies
We use (3+1) dimensional ideal hydrodynamics to describe the space-time
evolution of strongly interacting matter created in Au+Au and Pb+Pb collisions.
The model is applied for the domain of bombarding energies 1-160 AGeV which
includes future NICA and FAIR experiments. Two equations of state are used: the
first one corresponding to resonance hadron gas and the second one including
the deconfinement phase transition. The initial state is represented by two
Lorentz-boosted nuclei. Dynamical trajectories of matter in the central box of
the system are analyzed. They can be well represented by a fast shock-wave
compression followed by a relatively slow isentropic expansion. The parameters
of collective flows and hadronic spectra are calculated under assumption of the
isochronous freeze-out. It is shown that the deconfinement phase transition
leads to broadening of proton rapidity distributions, increase of elliptic
flows and formation of the directed antiflow in the central rapidity region.
These effects are most pronounced at bombarding energies around 10 AGeV, when
the system spends the longest time in the mixed phase. From the comparison with
three-fluid calculations we conclude that the transparency effects are not so
important in central collisions at NICA-FAIR energies (below 30 AGeV).Comment: 38 pages, 28 figure
MRD detection in multiple myeloma: comparison between MSKCC 10-color single-tube and EuroFlow 8-color 2-tube methods
[EN] In patients with multiple myeloma, obtaining posttreatment minimal residual disease (MRD) negativity is associated with longer progression-free survival and overall survival. Here, we compared the diagnostic performance of a single 10-color tube with that of a EuroFlow 8-color 2-tube panel for MRD testing. Bone marrow samples from 41 multiple myeloma patients were tested in parallel using the 2 approaches. Compared with the sum of the cells from the EuroFlow two 8-color tubes, the Memorial Sloan Kettering Cancer Center (MSKCC) single 10-color tube had a slight reduction in total cell number with a mean ratio of 0.85 (range, 0.57-1.46; P < .05), likely attributable to permeabilization of the cells. Percent of plasma cells showed a high degree of concordance (r2 = 0.97) as did normal plasma cells (r2 = 0.96), consistent with no selective plasma cell loss. Importantly, concordant measurement of residual disease burden was seen with abnormal plasma cells (r2 = 0.97). The overall concordance between the 2 tests was 98%. In 1 case, there was a discrepancy near the limit of detection of both tests in favor of the slightly greater theoretical sensitivity of the EuroFlow 8-color 2-tube panel (analytical sensitivity limit of MSKCC single 10-color tube: 6 cells in 1 million with at least 3 million cell acquisitions; EuroFlow 8-color 2-tube panel: 2 cells in 1 million with the recommended 10 million cell acquisitions)
Macrophage tropism of HIV-1 depends on efficient cellular dNTP utilization by reverse transcriptase
Retroviruses utilize cellular dNTPs to perform proviral DNA synthesis in infected host cells. Unlike oncoretroviruses, which replicate in dividing cells, lentiviruses, such as human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus, are capable of efficiently replicating in non-dividing cells (terminally differentiated macrophages) as well as dividing cells (i.e. activated CD4+ T cells). In general, non-dividing cells are likely to have low cellular dNTP content compared with dividing cells. Here, by employing a novel assay for cellular dNTP content, we determined the dNTP concentrations in two HIV-1 target cells, macrophages and activated CD4+ T cells. We found that human macrophages contained 130-250-fold lower dNTP concentrations than activated human CD4+ T cells. Biochemical analysis revealed that, unlike oncoretroviral reverse transcriptases (RTs), lentiviral RTs efficiently synthesize DNA even in the presence of the low dNTP concentrations equivalent to those found in macrophages. In keeping with this observation, HIV-1 vectors containing mutant HIV-1 RTs, which kinetically mimic oncoretroviral RTs, failed to transduce human macrophages despite retaining normal infectivity for activated CD4+ T cells and other dividing cells. These results suggest that the ability of HIV-1 to infect macrophages, which is essential to establishing the early pathogenesis of HIV-1 infection, depends, at least in part, on enzymatic adaptation of HIV-1 RT to efficiently catalyze DNA synthesis in limited cellular dNTP substrate environments
Radiological background of transverse flatfoot
The article deals the data of radiological indicators of deformity of the forefoot in 68 patients (91 feet), and determined the degree of transverse flatfoot, based on the average-normal indicators: M1M2, M1P1, M1M5. The dependence of the degree of valgus deviation of the first finger on the angle of inclination of the articular surfaces of the medial sphenoid bone and the first metatarsophalangeal joint (M1C1) was also revealed.В статье рассмотрены данные рентгенологических показателей деформации переднего отдела стопы у 68 пациентов (на 91 стопе), и определены степени поперечного плоскостопия, исходя из средненормальных показателей: М1М2 ,М1Р1, М1М5. Также выявлена зависимость степени вальгусного отклонения первого пальца от угла наклона суставных поверхностей медиальной клиновидной кости и первого плюснефалангового сустава (М1С1)
Investigation of the Chaotic Dynamics of an Electron Beam with a Virtual Cathode in an External Magnetic Field
The effect of the strength of the focusing magnetic field on chaotic dynamic
processes occurring inan electron beam with a virtual cathode, as well as on
the processes whereby the structures form in the beamand interact with each
other, is studied by means of two-dimensional numerical simulations based on
solving a self-consistent set of Vlasov-Maxwell equations. It is shown that, as
the focusing magnetic field is decreased,the dynamics of an electron beam with
a virtual cathode becomes more complicated due to the formation andinteraction
of spatio-temporal longitudinal and transverse structures in the interaction
region of a vircator. The optimum efficiency of the interaction of an electron
beam with the electromagnetic field of the vircator isachieved at a
comparatively weak external magnetic field and is determined by the
fundamentally two-dimensional nature of the motion of the beam electrons near
the virtual cathode.Comment: 12 pages, 8 figure
Experimental and Theoretical Investigation into the Effect of the Electron Velocity Distribution on Chaotic Oscillations in an Electron Beam under Virtual Cathode Formation Conditions
The effect of the electron transverse and longitudinal velocity spread at the
entrance to the interaction space on wide-band chaotic oscillations in intense
multiple-velocity beams is studied theoretically and numerically under the
conditions of formation of a virtual cathode. It is found that an increase in
the electron velocity spread causes chaotization of virtual cathode
oscillations. An insight into physical processes taking place in a virtual
cathode multiple velocity beam is gained by numerical simulation. The
chaotization of the oscillations is shown to be associated with additional
electron structures, which were separated out by constructing charged particle
distribution functions.Comment: 9 pages, 8 figure
Characterization of Coupled Ground State and Excited State Equilibria by Fluorescence Spectral Deconvolution
Fluorescence probes with multiparametric response based on the relative variation in the intensities of several emission bands are of great general utility. An accurate interpretation of the system requires the determination of the number, positions and intensities of the spectral components. We have developed a new algorithm for spectral deconvolution that is applicable to fluorescence probes exhibiting a two-state ground-state equilibrium and a two-state excited-state reaction. Three distinct fluorescence emission bands are resolved, with a distribution of intensities that is excitation-wavelength-dependent. The deconvolution of the spectrum into individual components is based on their representation as asymmetric Siano-Metzler log-normal functions. The application of the algorithm to the solvation response of a 3-hydroxychromone (3HC) derivative that exhibits an H-bonding-dependent excited-state intramolecular proton transfer (ESIPT) reaction allowed the separation of the spectral signatures characteristic of polarity and hydrogen bonding. This example demonstrates the ability of the method to characterize two potentially uncorrelated parameters characterizing dye environment and interactions
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