Studies of the cross section of gamma-neutron reactions on the
Nb nucleus were carried out on the bremsstrahlung of the linear electron accelerator LUE-75 which is located at the A. Alikhanyan ...National Science Laboratory (Yerevan Physics Institute). The experiment was done at 30 and 40 MeV bremsstrahlung end-point energies. The reaction cross sections for
Nb
Nb reactions were measured by the activation method with the spectrometric analysis using the High Purity Germanium detector (HPGe). The values of cross sections for different energies of photon beam were determined using the TALYS 1.95 and EMPIRE 3.2 nuclear codes. The energy distribution of photon spectra was performed using the GEANT4 package. The obtained experimental and theoretical results are compared with the available experimental data of other authors. Good agreement was observed between the theoretical and experimental data. The data on the reaction cross section for
Nb
Nb were obtained for the first time.
Development of a new type of Vibrating Wire Monitor (VWM), which has two mechanically coupled wires (vibrating and target), is presented. The new monitor has a much larger aperture size than the ...previous model of the VWM, and thus allows us to measure transverse beam halos more effectively. A prototype of such a large aperture VWM with a target wire length of 60 mm was designed, manufactured, and bench-tested. Initial beam measurements have been performed at the Fermilab High Intensity Neutrino Source (HINS) facility, and key results are presented.
In the recent years, an identification of regulatory mechanisms underlying the general adaptation syndrome as an organism’s response to drastic emotional stress-evoking environmental changes is ...gaining in its importance. The ability to control over visceral functions plays a crucial role in stress reactions due to a threat of neurodynamic imbalance in sympathetic-parasympathetic relationships with the heart as their most vulnerable element. Fast stress adaptation promotes restoration not only of the sympathetic-parasympathetic balance, but also of energy metabolism. Taurine is one of the major regulatory molecules that activate metabolic processes. The present work addresses the following issues: (1) the descending influence of the paraventricular nucleus (PVN) on neural reaction of the solitary tract nucleus (STN), which is the first link in the visceral sensitivity pathway, (2) the mechanisms of central control over visceral reactions as investigated by mathematical modelling and analysis of the heart rate variability (HRV), and (3) morphofunctional changes in brain structures, integrating and regulating the visceral sphere (hypothalamic PVN, amygdala), under psycho-emotional stress with and without intraperitoneal injection of taurine (50 mg/kg). Acute and semichronic experiments were conducted on white nonlinear rats under 5-h immobilization stress. An extremely strong centralization of the vegetative HRV parameters (HR, VBI, SSTI) was revealed, with these parameters normalized on days 7 and 14 post taurine injection. An interaction and interdependence of the central regulatory mechanisms of cardiovascular reactions as well as a considerable protective role of taurine, promoting fast restoration of adaptive properties of the central and peripheral visceral sensitivity components under the development of long-term psycho-emotional stress, were shown.
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