Casting Fe-Al-based intermetallics microalloyed with Li and Ag

The effect on the mechanical properties at room temperature of Li and Ag additions to the Fe–Al (40 at.%)-based alloy produced by conventional casting were evaluated in this work. Alloying elements were added into a previously molted Fe–(40 at.%) aluminum-based alloy, stirred, and then cast into sand molds to directly produce tensile specimens. To determine the mechanical properties, tensile tests and hardness measurements were performed. The additions of both Ag and Li showed an increase in ductility and tensile strength of the intermetallic alloys. In addition, hardness was substantially increased with the Li addition. Lithium additions promoted a solid solution hardening, whereas 3 at.% of Ag additions promoted ductility due to a microstructural modification and to the formation of a soft Ag 3 Al phase. Characterization by both optical and electronic microscopy, energy dispersive spectroscopy microanalysis, and x-ray diffraction supported the mechanical characterization.Peer ReviewedPostprint (author's final draft

The baryo-quarkonium picture for hidden-charm and bottom pentaquarks and LHCb Pc(4380) and Pc(4450) states

We study baryo-charmonium [ηc- and J/ψ-N⁎, ηc(2S)-, ψ(2S)- and χc(1P)-N] and baryo-bottomonium [ηb(2S)-, ϒ(2S)- and χb(1P)-N] bound states, where N is the nucleon and N⁎ a nucleon resonance. In the baryo-quarkonium model, the five qqqQQ¯ quarks are arranged in terms of a heavy quarkonium core, QQ¯, embedded in light baryonic matter, qqq, with q=u or d. The interaction between the QQ¯ core and the light baryon can be written in terms of the QCD multipole expansion. The spectrum of baryo-charmonium states is calculated and the results compared with the existing experimental data. In particular, we can interpret the recently discovered Pc(4380) and Pc(4450) pentaquarks as ψ(2S)-N and χc2(1P)-N bound states, respectively. We observe that in the baryo-bottomonium sector the binding energies are, on average, slightly larger than those of baryo-charmonia. Because of this, the hidden-bottom pentaquarks are more likely to form than their hidden-charm counterparts. We thus suggest the experimentalists to look for five-quark states in the hidden-bottom sector in the 10.4–10.9 GeV energy region. Keywords: Baryo-charmonium, QCD multipole expansion, Pentaquarks, Pc(4380) and Pc(4450

Etiology of subclinic mastitis in Patzcuaro Michoacan

[No abstract available

[Use of rituximab in resistant thrombocytopenic purpura]. [Rituximab en púrpura trombocitopénica inmune refractaria.]

immune thrombocytopenic purpura is characterized by bleeding disorders associated with decreased platelet count secondary to antiplatelet autoantibodies. The aim of this study was to evaluate the utility of rituximab in the management of refractory immune thrombocytopenic purpura. four women with immune thrombocytopenic purpura unresponsiveness to standard therapy were evaluated in relation to clinical response and total platelets counts at different time intervals after rituximab administration. All four patients developed petechiae; two of them associated with ecchymosis, one with hematemesis and one more with transvaginal bleeding. The mean baseline platelet count was 5350/μL; in the 60th day after the first dose of rituximab the average was 175 250/μL. Complete remission was considered in three patients. rituximab is a therapeutic option for refractory inmune thrombocytopenic purpura. Nevertheless, more studies are needed to evaluate its efficacy and safety

Casting Fe-Al-based intermetallics microalloyed with Li and Ag

The effect on the mechanical properties at room temperature of Li and Ag additions to the Fe–Al (40 at.%)-based alloy produced by conventional casting were evaluated in this work. Alloying elements were added into a previously molted Fe–(40 at.%) aluminum-based alloy, stirred, and then cast into sand molds to directly produce tensile specimens. To determine the mechanical properties, tensile tests and hardness measurements were performed. The additions of both Ag and Li showed an increase in ductility and tensile strength of the intermetallic alloys. In addition, hardness was substantially increased with the Li addition. Lithium additions promoted a solid solution hardening, whereas 3 at.% of Ag additions promoted ductility due to a microstructural modification and to the formation of a soft Ag 3 Al phase. Characterization by both optical and electronic microscopy, energy dispersive spectroscopy microanalysis, and x-ray diffraction supported the mechanical characterization.Peer Reviewe

Diquark correlations in hadron physics: Origin, impact and evidence

The last decade has seen a marked shift in how the internal structure of hadrons is understood. Modern experimental facilities, new theoretical techniques for the continuum bound-state problem and progress with lattice-regularised QCD have provided strong indications that soft quark+quark (diquark) correlations play a crucial role in hadron physics. For example, theory indicates that the appearance of such correlations is a necessary consequence of dynamical chiral symmetry breaking, viz. a corollary of emergent hadronic mass that is responsible for almost all visible mass in the universe; experiment has uncovered signals for such correlations in the flavour-separation of the proton's electromagnetic form factors; and phenomenology suggests that diquark correlations might be critical to the formation of exotic tetra- and penta-quark hadrons. A broad spectrum of such information is evaluated herein, with a view to consolidating the facts and there from moving toward a coherent, unified picture of hadron structure and the role that diquark correlations might play. (C) 2020 Published by Elsevier B.V

Diquark correlations in hadron physics : origin, impact and evidence

The last decade has seen a marked shift in how the internal structure of hadrons is understood. Modern experimental facilities, new theoretical techniques for the continuum bound-state problem and progress with lattice-regularised QCD have provided strong indications that soft quark+quark (diquark) correlations play a crucial role in hadron physics. For example, theory indicates that the appearance of such correlations is a necessary consequence of dynamical chiral symmetry breaking, viz. a corollary of emergent hadronic mass that is responsible for almost all visible mass in the universe; experiment has uncovered signals for such correlations in the flavour-separation of the proton’s electromagnetic form factors; and phenomenology suggests that diquark correlations might be critical to the formation of exotic tetra- and penta-quark hadrons. A broad spectrum of such information is evaluated herein, with a view to consolidating the facts and therefrom moving toward a coherent, unified picture of hadron structure and the role that diquark correlations might play.peerReviewe