5,404 research outputs found

    Remarks on a normal subgroup of GA_n

    Full text link
    We show that the subgroup generated by locally finite polynomial automorphisms of k^n is normal in GA_n. Also, some properties of normal subgroups of GA_n containing all diagonal automorphisms are given.Comment: 5 page

    Reevaluation of Neutron Electric Dipole Moment with QCD Sum Rules

    Full text link
    We study the neutron electric dipole moment in the presence of the CP-violating operators up to the dimension five in terms of the QCD sum rules. It is found that the OPE calculation is robust when exploiting a particular interpolating field for neutron, while there exist some uncertainties on the phenomenological side. By using input parameters obtained from the lattice calculation, we derive a conservative limit for the contributions of the CP violating operators. We also show the detail of the derivation of the sum rules.Comment: 33 pages, 5 figure

    Estudo da diversidade de begomovirus em tomateiro cultivado na região da caatinga do Brasil.

    Get PDF
    O presente trabalho teve como objetivo analisar a diversidade de begomovirus infectando tomateiro no Nordeste brasileiro.Resumo 673-

    A one-sided Prime Ideal Principle for noncommutative rings

    Full text link
    Completely prime right ideals are introduced as a one-sided generalization of the concept of a prime ideal in a commutative ring. Some of their basic properties are investigated, pointing out both similarities and differences between these right ideals and their commutative counterparts. We prove the Completely Prime Ideal Principle, a theorem stating that right ideals that are maximal in a specific sense must be completely prime. We offer a number of applications of the Completely Prime Ideal Principle arising from many diverse concepts in rings and modules. These applications show how completely prime right ideals control the one-sided structure of a ring, and they recover earlier theorems stating that certain noncommutative rings are domains (namely, proper right PCI rings and rings with the right restricted minimum condition that are not right artinian). In order to provide a deeper understanding of the set of completely prime right ideals in a general ring, we study the special subset of comonoform right ideals.Comment: 38 page

    Pressure-induced phase transition and bi-polaronic sliding in a hole-doped Cu_2O_3 ladder system

    Full text link
    We study a hole-doped two-leg ladder system including metal ions, oxygen, and electron-lattice interaction, as a model for Sr_{14-x}Ca_xCu_{24}O_{41-\delta}. Single- and bi-polaronic states at 1/4-hole doping are modeled as functions of pressure by applying an unrestricted Hartree-Fock approximation to a multiband Peierls-Hubbard Hamiltonian. We find evidence for a pressure-induced phase transition between single-polaron and bi-polaron states. The electronic and phononic excitations in those states, including distinctive local lattice vibrational modes, are calculated by means of a direct-space Random Phase approximation. Finally, as a function of pressure, we identify a transition between site- and bond-centered bi-polarons, accompanied by a soft mode and a low-energy charge-sliding mode. We suggest comparisons with available experimented data

    Pathophysiological mechanisms in neurodevelopmental disorders caused by rac GTPases dysregulation: What’s behind neuro-RACopathies

    Get PDF
    Rho family guanosine triphosphatases (GTPases) regulate cellular signaling and cytoskele-tal dynamics, playing a pivotal role in cell adhesion, migration, and cell cycle progression. The Rac subfamily of Rho GTPases consists of three highly homologous proteins, Rac 1–3. The proper function of Rac1 and Rac3, and their correct interaction with guanine nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs) are crucial for neural development. Pathogenic variants affecting these delicate biological processes are implicated in different medical conditions in humans, primarily neurodevelopmental disorders (NDDs). In addition to a direct deleterious effect produced by genetic variants in the RAC genes, a dysregulated GTPase activity resulting from an abnormal function of GEFs and GAPs has been involved in the pathogenesis of distinctive emerging conditions. In this study, we reviewed the current pertinent literature on Rac-related disorders with a primary neurological involvement, providing an overview of the current knowledge on the pathophysiological mechanisms involved in the neuro-RACopathies

    Incidência de begomovírus de tomateiro em amostras de soja coletadas durante o período do vazio fitossanitário em 2013/2014.

    Get PDF
    O objetivo deste trabalho foi avaliar a incidência de Tomato severe rugose virus (ToSRV), o principal begomovírus de tomateiro, em amostras de soja coletadas durante o período de vazio fitossanitário do tomateiro (novembro a janeiro).Resumo 15
    corecore