11 research outputs found

    Transverse and longitudinal momentum spectra of fermions produced in strong SU(2) fields

    Full text link
    We study the transverse and longitudinal momentum spectra of fermions produced in a strong, time-dependent non-Abelian SU(2) field. Different time-dependent field strengths are introduced. The momentum spectra are calculated for the produced fermion pairs in a kinetic model. The obtained spectra are similar to the Abelian case, and they display exponential or polynomial behaviour at high p_T, depending on the given time dependence. We investigated different color initial conditions and discuss the recognized scaling properties for both Abelian and SU(2) cases.Comment: 10 pages, 11 figures; version accepted to PR

    Theoretical prerequisites for substantiating the parameters of a rotary ripper for interrow potato cultivation

    Get PDF
    The article is devoted to the study of the process of interaction of the rotary ripper’s working bodies with the soil. The classification of rotary machines and implements according to the energy transmitted to the working body and the location of the rotation axis is outlined. The article notes that the main characteristics of the rotor work body motion are the trajectory type, the magnitude and direction of velocity of its most characteristic point, and in some cases, the magnitude and direction of acceleration. The article presents the results of theoretical research in the field of kinematics of interaction of rotary working tools with the soil. The design of the rotary ripper is presented and the description of the trajectory of its working bodies is made, the value of movement of the scraper plate in the contact area with the soil is established. We analyzed the segment of the path from the beginning of contact with the soil (the beginning of dragging the surface layer of soil) and the end of contact (the end of dragging the surface layer of soil), on the line of which weed combing, loosening and destruction of soil crust occurs

    Intrinsic Order and Disorder in the Bcl-2 Member Harakiri: Insights into Its Proapoptotic Activity

    Get PDF
    Harakiri is a BH3-only member of the Bcl-2 family that localizes in membranes and induces cell death by binding to prosurvival Bcl-xL and Bcl-2. The cytosolic domain of Harakiri is largely disorder with residual α-helical conformation according to previous structural studies. As these helical structures could play an important role in Harakiri's function, we have used NMR and circular dichroism to fully characterize them at the residue-atomic level. In addition, we report structural studies on a peptide fragment spanning Harakiri's C-terminal hydrophobic sequence, which potentially operates as a transmembrane domain. We initially checked by enzyme immunoassays and NMR that peptides encompassing different lengths of the cytosolic domain are functional as they bind Bcl-xL and Bcl-2. The structural data in water indicate that the α-helical conformation is restricted to a 25-residue segment comprising the BH3 domain. However, structure calculation was precluded because of insufficient NMR restraints. To bypass this problem we used alcohol-water mixture to increase structure population and confirmed by NMR that the conformation in both milieus is equivalent. The resulting three-dimensional structure closely resembles that of peptides encompassing the BH3 domain of BH3-only members in complex with their prosurvival partners, suggesting that preformed structural elements in the disordered protein are central to binding. In contrast, the transmembrane domain forms in micelles a monomeric α-helix with a population close to 100%. Its three-dimensional structure here reported reveals features that explain its function as membrane anchor. Altogether these results are used to propose a tentative structural model of how Harakiri works

    Theoretical prerequisites for substantiating the parameters of a rotary ripper for interrow potato cultivation

    No full text
    The article is devoted to the study of the process of interaction of the rotary ripper’s working bodies with the soil. The classification of rotary machines and implements according to the energy transmitted to the working body and the location of the rotation axis is outlined. The article notes that the main characteristics of the rotor work body motion are the trajectory type, the magnitude and direction of velocity of its most characteristic point, and in some cases, the magnitude and direction of acceleration. The article presents the results of theoretical research in the field of kinematics of interaction of rotary working tools with the soil. The design of the rotary ripper is presented and the description of the trajectory of its working bodies is made, the value of movement of the scraper plate in the contact area with the soil is established. We analyzed the segment of the path from the beginning of contact with the soil (the beginning of dragging the surface layer of soil) and the end of contact (the end of dragging the surface layer of soil), on the line of which weed combing, loosening and destruction of soil crust occurs

    Development and theoretical study of the impact of the working body on the soil

    No full text
    The article presents the theoretical results of the performance indicators of the defoliator. They depend on the parameters and modes of the defoliator operation. It operates on the basis of the description of the justification, which is provided in the work. The combined defoliator is aimed at removing potato tops with working bodies. They are multiple in number and they combine the consistency of their rotation including their vertical axis. Moreover, with the horizontal axis they are in the zone of their interaction without touching each other

    The Rationale for the Optimal Continuous-Variable Quantum Key Distribution Protocol

    No full text
    This article describes the current technical level of developments in the field of continuous-variable quantum key distribution (CV-QKD). Various classifications are described, the criteria are analyzed, and the optimal protocol is selected. The analysis is focused around device-dependent schemes with a theoretical emphasis, and therefore, a detailed analysis of device-independent CV-QKD and side-channel attacks is out of the scope of the work. However, the latter, one way or another, is taken into account when describing possible classifications. The choice of the optimal protocol was carried out, first of all, from the potential possibility of integration into existing network telecommunication infrastructures. Predominantly, the general classification is carried out in such a way that it is possible to draw up a specific protocol, depending on the task of implementation
    corecore