115 research outputs found
Local triple derivations on real C*-algebras and JB*-triples
We study when a local triple derivation on a real JB*-triple is a triple
derivation. We find an example of a (real linear) local triple derivation on a
rank-one Cartan factor of type I which is not a triple derivation. On the other
hand, we find sufficient conditions on a real JB*-triple E to guarantee that
every local triple derivation on E is a triple derivation
2-local triple homomorphisms on von Neumann algebras and JBW-triples
We prove that every (not necessarily linear nor continuous) 2-local triple
homomorphism from a JBW-triple into a JB-triple is linear and a triple
homomorphism. Consequently, every 2-local triple homomorphism from a von
Neumann algebra (respectively, from a JBW-algebra) into a C-algebra
(respectively, into a JB-algebra) is linear and a triple homomorphism
Local triple derivations on C*-algebras
We prove that every bounded local triple derivation on a unital C*-algebra is
a triple derivation. A similar statement is established in the category of
unital JB*-algebras.Comment: 12 pages, submitte
Seasons and planting densities interaction on forage production of eight hybrids maize, Ecuador
ABSTRACT
Objective. To assess the interaction effect of the season and planting densities on the production of eight INIAP corn hybrids. Materials and methods. A research process was conducted in 2013. It was applied a split - split plot design with three replication and Tukey test was used. It was evaluated two planting seasons (28 January and 8 April), they were placed in large plots. Two planting densities (65,500 y 125,000 plants/ha), that were located in the subplots and eight INIAP corn hybrids arranged in the sub- subplots. The evaluated variables were Fresh Matter, Dry Matter, Plant Height and Crude Protein Results. Fresh Matter and Crude Protein productions were influenced by planting seasons. Plant densities affected the production of Fresh Matter, Dry Matter and Plant Height, as well as the interaction season by corn INIAP hybrids. While INIAP corn hybrids showed statistical differences in the production of Fresh, Dry Matter, Plant Height and Crude Protein. The eight INIAP hybrids productions were: Fresh Matter (58.86 ton/ha ±5.19); Dry Matter (21.45 ton/ha ±4.71); Plant Height (2.46 m ±0.16) and Crude Protein (10.6±1.12). Conclusions. The performance showed by hybrids INIAP CML-172, INIAP 6021 and INIAP 551 were very acceptable forage material and could be used for silage purposes.
RESUMEN
Objetivo. Evaluar el efecto de la interaccioÌn eÌpoca y densidad de siembra en ocho hiÌbridos de maiÌz para produccioÌn de forraje sobre la obtencioÌn de materia fresca MF, seca MS, altura de planta AP y proteiÌna cruda PC. Materiales y meÌtodos. Se empleoÌ un disenÌo de parcela dos veces dividida con tres repeticiones. Se evaluoÌ el efecto de dos eÌpocas de siembra (28 de enero y el 8 de abril) que se dispusieron en la parcelas grandes, dos densidades de siembra (65.500 y 125.000 plantas/ha) que se ubicaron en las subparcelas y ocho hiÌbridos de maiÌz INIAP dispuestas en las sub-subparcelas. Las variables evaluadas fueron produccioÌn de MF, MS, AP y PC. Resultados. La eÌpoca de siembra tuvo su influencia sobre la produccioÌn de MF y contenido de PC. La densidad de cultivo y eÌpoca de siembra afectoÌ la produccioÌn de MF, MS y AP por hiÌbridos de maiÌz. Mientras que los hiÌbridos INIAP de maiÌz mostraron diferencias estadiÌsticas (p<0.001) en la produccioÌn de MF, MS, AP y PC. La produccioÌn de los ocho hiÌbridos INIAP fue de MF (58.86 Ton/ha ±5.19); MS (21.45 Ton/ha ±4.71); AP (2.46 m±0.16) y PC (10.6±1.12). Conclusiones. Los rendimientos mostrados por los hiÌbridos INIAP CML 172, INIAP 6021 e INIAP 551 son materiales aceptables con relacioÌn a las variables evaluadas y pueden ser empleados especialmente para ensilaje
Intramolecular hydrogen bond activation: Thiourea-organocatalyzed enantioselective 1,3-dipolar cycloaddition of salicylaldehyde-derived azomethine ylides with nitroalkenes
An organocatalytic strategy for the synthesis of tetrasubstituted pyrrolidines with monoactivated azomethine ylides in high enantiomeric excess and excellent exo/endo selectivity is presented. The key to success is the intramolecular activation via hydrogen bonding through an o-hydroxy group, which allows the dipolar cycloaddition to take place in the presence of azomethine ylides bearing only one activating group. The intramolecular hydrogen bond in the azomethine ylide and the intermolecular hydrogen bond with the catalyst have been demonstrated by DFT calculations and mechanistic proofs to be crucial for the reaction to proceedThe Spanish Government (CTQ2015-64561-R, CTQ2016-
76061-P) and the European Research Council (ERC-CG,
contract number 647550) are acknowledged. We acknowledge
the generous allocation of computing time at the CCC (UAM).
S.D.-T. gratefully acknowledges the âRamoÌn y Cajalâ program
(RYC-2010-07019). Financial support from the Spanish
Ministry of Economy and Competitiveness, through the
âMaria de Maeztuâ Program of Excellence in R&D (MDM-
2014-0377
Energy dependence of Ï meson production at forward rapidity in pp collisions at the LHC
The production of mesons has been studied in pp collisions at LHC energies with the ALICE detector via the dimuon decay channel in the rapidity region . Measurements of the differential cross section are presented as a function of the transverse momentum () at the center-of-mass energies , 8 and 13 TeV and compared with the ALICE results at midrapidity. The differential cross sections at and 13 TeV are also studied in several rapidity intervals as a function of , and as a function of rapidity in three intervals. A hardening of the -differential cross section with the collision energy is observed, while, for a given energy, spectra soften with increasing rapidity and, conversely, rapidity distributions get slightly narrower at increasing . The new results, complementing the published measurements at and 7 TeV, allow one to establish the energy dependence of meson production and to compare the measured cross sections with phenomenological models. None of the considered models manages to describe the evolution of the cross section with and rapidity at all the energies.publishedVersio
First measurement of coherent Ï0 photoproduction in ultra-peripheral XeâXe collisions at âsNN = 5.44 TeV
The first measurement of the coherent photoproduction of Ï0 vector mesons in ultra-peripheral XeâXe collisions at sNN=5.44 TeV is presented. This result, together with previous HERA Îłp data and ÎłâPb measurements from ALICE, describes the atomic number (A) dependence of this process, which is particularly sensitive to nuclear shadowing effects and to the approach to the black-disc limit of QCD at a semi-hard scale. The cross section of the Xe+XeâÏ0+Xe+Xe process, measured at midrapidity through the decay channel Ï0âÏ+Ïâ, is found to be dÏ/dy=131.5±5.6(stat.)â16.9+17.5(syst.) mb. The ratio of the continuum to resonant contributions for the production of pion pairs is also measured. In addition, the fraction of events accompanied by electromagnetic dissociation of either one or both colliding nuclei is reported. The dependence on A of cross section for the coherent Ï0 photoproduction at a centre-of-mass energy per nucleon of the ÎłA system of WÎłA,n=65 GeV is found to be consistent with a power-law behaviour Ï(ÎłAâÏ0A)âAα with a slope α=0.96±0.02(syst.). This slope signals important shadowing effects, but it is still far from the behaviour expected in the black-disc limit.publishedVersio
Ï production in pâPb collisions at sNN=8.16Â TeV
Ïproduction in pâPbinteractions is studied at the centre-of-mass energy per nucleonânucleon collision âsNN=8.16TeV with the ALICE detector at the CERN LHC. The measurement is performed reconstructing bottomonium resonances via their dimuon decay channel, in the centre-of-mass rapidity intervals 2.03 <3.53and â4.46 <â2.96, down to zero transverse momentum. In this work, results on the Ï(1S) production cross section as a function of rapidity and transverse momentum are presented. The corresponding nuclear modification factor shows a suppression of the Ï(1S) yields with respect to ppcollisions, both at forward and backward rapidity. This suppression is stronger in the low transverse momentum region and shows no significant dependence on the centrality of the interactions. Furthermore, the Ï(2S) nuclear modification factor is evaluated, suggesting a suppression similar to that of the Ï(1S). A first measurement of the Ï(3S) has also been performed. Finally, results are compared with previous ALICE measurements in pâPbcollisions at âsNN=5.02TeV and with theoretical calculations
Effect of surgical experience and spine subspecialty on the reliability of the {AO} Spine Upper Cervical Injury Classification System
OBJECTIVE
The objective of this paper was to determine the interobserver reliability and intraobserver reproducibility of the AO Spine Upper Cervical Injury Classification System based on surgeon experience (< 5 years, 5â10 years, 10â20 years, and > 20 years) and surgical subspecialty (orthopedic spine surgery, neurosurgery, and "other" surgery).
METHODS
A total of 11,601 assessments of upper cervical spine injuries were evaluated based on the AO Spine Upper Cervical Injury Classification System. Reliability and reproducibility scores were obtained twice, with a 3-week time interval. Descriptive statistics were utilized to examine the percentage of accurately classified injuries, and Pearsonâs chi-square or Fisherâs exact test was used to screen for potentially relevant differences between study participants. Kappa coefficients (Îș) determined the interobserver reliability and intraobserver reproducibility.
RESULTS
The intraobserver reproducibility was substantial for surgeon experience level (< 5 years: 0.74 vs 5â10 years: 0.69 vs 10â20 years: 0.69 vs > 20 years: 0.70) and surgical subspecialty (orthopedic spine: 0.71 vs neurosurgery: 0.69 vs other: 0.68). Furthermore, the interobserver reliability was substantial for all surgical experience groups on assessment 1 (< 5 years: 0.67 vs 5â10 years: 0.62 vs 10â20 years: 0.61 vs > 20 years: 0.62), and only surgeons with > 20 years of experience did not have substantial reliability on assessment 2 (< 5 years: 0.62 vs 5â10 years: 0.61 vs 10â20 years: 0.61 vs > 20 years: 0.59). Orthopedic spine surgeons and neurosurgeons had substantial intraobserver reproducibility on both assessment 1 (0.64 vs 0.63) and assessment 2 (0.62 vs 0.63), while other surgeons had moderate reliability on assessment 1 (0.43) and fair reliability on assessment 2 (0.36).
CONCLUSIONS
The international reliability and reproducibility scores for the AO Spine Upper Cervical Injury Classification System demonstrated substantial intraobserver reproducibility and interobserver reliability regardless of surgical experience and spine subspecialty. These results support the global application of this classification system
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