103,059 research outputs found
On Multiple Polynomials of Capelli Type
No full textThis paper deals with the class of Capelli polynomials in free associative algebra F{Z} (where F is an arbitrary field, Z is a countable set) generalizing the construction of multiple Capelli polynomials. The fundamental properties of the introduced Capelli polynomials are provided. In particular, decomposition of the Capelli polynomials by means of the same type of polynomials is shown. Furthermore, some relations between their T -ideals are revealed. A connection between double Capelli polynomials and Capelli quasi-polynomials is established
Capelli elements of the group algebra
No full textInspired by the Capelli identities for group determinants obtained by T\^oru
Umeda, we give a basis of the center of the group algebra of any finite group
by using Capelli identities for irreducible representations.
The Capelli identities for irreducible representations are modifications of
the Capelli identity. These identities lead to Capelli elements of the group
algebra. These elements construct a basis of the center of the group algebra
Molecular Motion in Crystalline Naphthalene: Analysis of Multi-Temperature X-ray and Neutron Diffraction Data
No full textSingle crystals of h8-naphthalene have been examined by both X-ray and neutron diffraction over a range of temperatures from 5 to 295 K. The aim of this case study was to measure the anisotropic displacement parameters (ADPs) of carbons and hydrogens and to interpret them using the model of thermal motion proposed by Bürgi and Capelli (Acta Cryst. 2000, A56, 403). The traditional rigid-body analysis expresses the low-frequency motions in terms of molecular translations and librations only, whereas the Bürgi-Capelli treatment also includes the high-frequency internal modes. We show that a considerable improvement occurs by representing the internal modes by a single second-rank tensor and that a further improvement follows by including a Grüneisen parameter to account for volume thermal expansion. By applying the treatment to multi-temperature diffraction data, there is a considerable reduction in the ratio of number of adjustable parameters/number of independent observations
ON THE ASYMPTOTICS OF CAPELLI POLYNOMIALS
No full textAbstract. We present old and new results about Capelli polynomials, Z2-graded Capelli
polynomials and Capelli polynomials with involution and their asymptotics.
Let Capm = Pσ2Sm (sgnσ)tσ(1)x1tσ(2) · · · tσ(m−1)xm−1tσ(m) be the m-th Capelli
polynomial of rank m. In the ordinary case (see [33]) it was proved the asymptotic
equality between the codimensions of the T -ideal generated by the Capelli polynomial
Capk2+1 and the codimensions of the matrix algebra Mk(F ). In [9] this result was
extended to superalgebras proving that the Z2-graded codimensions of the T2-ideal generated by the Z2-graded Capelli polynomials Cap0 M+1 and Cap1 L+1 for some fixed M,
L, are asymptotically equal to the Z2-graded codimensions of a simple finite dimensional
superalgebra. Recently, the authors proved that the ∗-codimensions of a ∗-simple finite dimensional algebra are asymptotically equal to the ∗-codimensions of the T-∗-ideal
generated by the ∗-Capelli polynomials Cap+ M+1 and Cap− L+1, for some fixed natural
numbers M and L
Effects of 17 days bed rest on maximal voluntary isometric torque and neuromuscular activation of leg muscles.
No full textMaximal voluntary isometric torque values of the ankle plantar (T-im,T-PF) and dorsal flexors (T-im,T-DF) were assessed in eight healthy adult males at 5 degrees and 15 degrees of dorsal flexion (DF) and at 5 degrees, 15 degrees and 25 degrees of plantar flexion (PF) with the knee at right angles, before (two times), during (three times) and after (three times) 17 days of 6 degrees head-down tilt bedrest (BR). Integrated electromyograms (iEMG) were also recorded from the gastrocnemius medialis and tibialis anterior. T-im,T-PF and the iEMG of the gastrocnemius medialis were significantly larger (by 14% and by 27%, respectively) at the end of recovery than before BR. This was probably the consequence of training and/or habituation leading to: (1) increased activation of the plantar flexors and (2) decreased co-activation of the antagonist muscles. Neither T-im,T-DF nor the tibialis anterior iEMG changed significantly. The effects of BR on muscle performance were evaluated as follows. The net torque generated by a given muscle group was assumed to be the algebraic sum of the torque generated by the agonists and by the antagonists. Thus, for the plantar flexors T-im,T-PF = alpha iEMG(Gm) - beta iEMG(Ta), where: (1) iEMG(Gm) and iEMG(Ta) are the iEMGs of gastrocnemius medialis and of tibialis anterior during maximal PF; and (2) the constants alpha and beta represent the electromechanical coupling of the plantar (a) and dorsal (beta) flexors. Similarly for the dorsal flexors: T-im,T-DF = beta iEMG(Ta) - alpha iEMG(Gm), where iEMG(Ta) and iEMG(Gm) are the iEMGs of tibialis anterior and gastrocnemius medialis during maximal DF. Torque and iEMG values were assessed for all subjects under all experimental conditions. Thus, since the biomechanical leverage of the system was constant, alpha and beta could be calculated. During BR, alpha decreased by 25% and it dropped by a further 30% during recovery. In contrast, beta remained almost unchanged. This suggests that, in spite of training and/or habituation, BR significantly impaired the maximal isometric performance of the plantar flexors, an effect that continued during the initial 10 days of recovery
Caratteristiche tipologiche ed archeometriche di un’area produttiva del XIII secolo da scoprire
No full textProposte per una scheda descrittiva delle sezioni sottili e per una classificazione minero-petrografica delle ceramiche
No full textLe ceramiche con rivestimenti vetrosi al piombo: conoscenze scientifiche e problemi archeologici
No full text
Evoluzione metodologica nelle ricerche archeometriche di provenienza. Il riesame delle ceramiche medievali di Castel Delfino nel quadro delle produzioni e delle importazioni liguri
No full text- …
