254 research outputs found
Cross-sections for the multiparticle reaction at = 40 95 MeV
The bremsstrahlung flux-averaged cross-sections and the cross-sections per equivalent photon
were measured for the
photonuclear multiparticle reaction at bremsstrahlung end-point
energies ranging from 40 MeV to 95 MeV. The experiments were performed using
the beam from the NSC KIPT electron linear accelerator LUE-40 with the use of
the -activation technique. The bremsstrahlung quantum flux was
calculated with the program GEANT4 and, in addition, was monitored by means of
the reaction. The cross-sections
were computed using the TALYS1.9 code with the default options. The
measured average cross-sections
and have appeared to be
higher by factors of 2.0 to 2.4 than the theoretical results. The experimental
results have been found to be in good agreement with the data of other
laboratories. Consideration is given to special features of calculation of
and for the
reaction, with occurrence of
three photodisintegration channels. The paper also discusses
the possibility of using the
reaction for monitoring the bremsstrahlung -quantum flux in the photon
energy region above 30 MeV.Comment: 16 pages, 6 figures, 1 tabl
Saturation of Coulomb sum rules in the 6^Li case
The Coulomb sums S_L(q) of the 6^Li nucleus have been obtained from electron
scattering measurements at 3-momentum transfers q = 1.125 - 1.625 fm^{-1}. It
is found that at q > 1.35 fm^{-1} the Coulomb sum of the nucleus becomes
saturated: S_L(q) = 1.Comment: 6 pages, 4 figures, 1 tabl
Bone marrow fibrosis – the basis of mielofibrosis: pathogenesis, prognostication and antifibrogenic targeted strategies.
Bone marrow fibrosis is a key patological feature and major diagnostic criterion of mielofibrosis. Although bone marrow fibrosis is manifested in a variety of malignant and non-malignant disease states, the deposition of reticulin and collagen fibrosis in the bone marrow of patients with myelofibrosis is believed to be mediated by the mielofibrosis of hematopoietic stem/progenitor cells, contributing to an impaired microenvironment toward malignant over normal hematopoiesis. The increased expression of proinflammatory cytokines, transforming growth factor-β, impaired megakaryocyte function and aberrant JAK-STAT signaling are the peculiarities of pathogenesis of bone marrow fibrosis. Hematopoietic stem cell transplantation remains the only therapeutic approach that reliably results in resolution of bone marrow fibrosis in patients with mielofibrosis. In the work we review the pathogenesis, biological consequences and prognostic results of impact of bone marrow fibrosis. We discuss the rationale of various anti-fibrogenic treatment strategies targeting at clonal hematopoietic stem/progenitor cells, aberrant signaling pathway, fibrogenic cytokines, and tumor microenvironment
Simulation of non-stationary processes in centrifugal cascades
The model of nonstationary hydraulic and dividing processes in rectangular symmetrical counterstream centrifugal cascades is considered. The calculation technique of centrifugal cascade parameters of transition processes has been developed. The results of numerical computation are presented
Bence-Jones protein as the form of nano-scaled β-stacked supramolecular aggregates
Abstract. The formation in β-structured protein aggregates in tissues and fluids of the body is one of the most dangerouse complications of various diseases. The most famous of them are amyloidoses, but they such deposits are observed at other, much more widespread, diseases. The generally accepted approach to amyloids’detectionis based on high-specific coloring by Congo Red dye. However, the Abbe's diffraction limit excludes the seeing of the objects smaller than 0.61 wavelengths (about 240 nm). Such nanoscale formations are capable to disrup the functioning of surrounding tissues, to causethe complications and recurrences of the disease, and to pass through biological barriers with the following accumulation in body’s fluids. It’s likely that these conditions are the cause of the urinary congophilia, that is associated with preeclampsia at pregnancy and chronic kidney disease. Nor the less suspicious object is the Bens-Jones protein that appears in the urine at multiple myeloma and some other diseases, which are in more or less extent,are related to the disturbance of protein metabolism.
The purpose of this study was to clarify the aggregate state of the Bens-Jones protein as a possible β-structured supramolecular associate.
Methods.The subject of the study was the freshly received urine from a patient with multiple myeloma. The presence of the Bens-Jones protein was checked by thermopacification of the acidified sample. For control, the urine was used by a healthy person with the addition of certain amounts of human serum albumin ("Reanal", Hungary) with a concentration of 0, 0.01, 0.1 and 1%.
Result. The obtained data testify to the appropriateness of such a point of view and create preresquites for the expanding of diagnostic possibilities.
Conclusions.The results obtained during the study testify to the peculiarity of the structure of the Bens-Jones protein, which is nano-sized beta-structured supramolecula
Production of Hf in photoproton reaction Ta at energy = 35-95 MeV
The production of the nuclei in the photoproton
reaction was studied at end-point bremsstrahlung
energies = 35-95 MeV. The experiment was performed at the
electron linear accelerator LUE-40 NSC KIPT with the use of the
activation and off-line -ray spectroscopy.
The experimental values of the bremsstrahlung flux-averaged cross-sections
for the
reaction were determined, and at
MeV obtained for the first time.
The measured values, also as the literature data, are significantly exceed
the theoretical flux-averaged cross-sections . The values were calculated using the cross-section
computed with the TALYS1.95 code for six different level density
models.
A comparative analysis of the calculated total cross-sections for the
reactions and
was performed. It was shown that the
photoproton to photoneutron strength ratio is
consistent with the estimates based on the isospin selection rules and the
value from the experiment.Comment: 9 pages, 4 figures, 2 table
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