An "Accidental" Symmetry Operator for the Dirac Equation in the Coulomb Potential

On the basis of the generalization of the theorem about K-odd operators (K is the Dirac's operator), certain linear combination is constructed, which appears to commute with the Dirac Hamiltonian for Coulomb field. This operator coincides with the Johnson and Lippmann operator and is intimately connected to the familiar Laplace-Runge-Lenz vector. Our approach guarantees not only derivation of Johnson-Lippmann operator, but simultaneously commutativity with the Dirac Hamiltonian follows.Comment: 6 page

Continuous ultrafiltration/diafiltration using a 3D‐printed two membrane single pass module

A 3D printed ultrafiltration/diafiltration (UF/DF) module is presented allowing the continuous, simultaneous concentration of retained (bio‐)molecules and reduction or exchange of the salt buffer. Differing from the single‐pass UF concepts known from the literature, DF operation does not require the application of several steps or units with intermediating dilution. In contrast, the developed module uses two membranes confining the section in which the molecules are concentrated while the sample is passing. Simultaneously to this concentration process, the two membranes allow a perpendicular in and outflow of DF buffer reducing the salt content in this section. The module showed the continuous concentration of a dissolved protein up to a factor of 4.6 while reducing the salt concentration down to 47% of the initial concentration along a flow path length of only 5 cm. Due to single‐pass operation the module shows concentration polarization effects reducing the effective permeability of the applied membrane in case of higher concentration factors. However, because of its simple design and the capability to simultaneously run UF and DF processes in a single module, the development could be economically beneficial for small scale UF/DF applications

Honesty mediates the relationship between serotonin and reaction to unfairness

How does one deal with unfair behaviors? This subject has long been investigated by various disciplines including philosophy, psychology, economics, and biology. However, our reactions to unfairness differ from one individual to another. Experimental economics studies using the ultimatum game (UG), in which players must decide whether to accept or reject fair or unfair offers, have also shown that there are substantial individual differences in reaction to unfairness. However, little is known about psychological as well as neurobiological mechanisms of this observation. We combined a molecular imaging technique, an economics game, and a personality inventory to elucidate the neurobiological mechanism of heterogeneous reactions to unfairness. Contrary to the common belief that aggressive personalities (impulsivity or hostility) are related to the high rejection rate of unfair offers in UG, we found that individuals with apparently peaceful personalities (straightforwardness and trust) rejected more often and were engaged in personally costly forms of retaliation. Furthermore, individuals with a low level of serotonin transporters in the dorsal raphe nucleus (DRN) are honest and trustful, and thus cannot tolerate unfairness, being candid in expressing their frustrations. In other words, higher central serotonin transmission might allow us to behave adroitly and opportunistically, being good at playing games while pursuing self-interest. We provide unique neurobiological evidence to account for individual differences of reaction to unfairness

Microstructure and mechanical effects of spark plasma sintering in alumina monolithic ceramics

The specific effects of spark plasma sintering (SPS) on the creep behavior, microstructure and mechanical properties of alumina monolithic ceramic were investigated. SPS introduces strains that concentrate at grain boundaries and inhibit crack growth, resulting in an improvement in the flexural strength and fracture toughness. However, creep blocks grain boundary movements and decreases the reliability of the material. These strains can be removed by a post-sintering thermal treatment, which plays an important role in the distribution of dislocations. Crown Copyright (c) 2012 Published by Elsevier Ltd. on behalf of Acta Materialia Inc. All rights reserved.The authors would like to acknowledge the help of the EU for the financial support received under the IP-NANOKER NMP3-CT-2005-515784. A.B. acknowledges the Spanish Ministry of Science and Innovation for her Juan de la Cierva Contract (JCI-2011-10498). The authors are grateful to the Central Support Service in Experimental Research (SCSIE), University of Valencia for providing the HR-TEM facility.Alvarez-Clemares, I.; Borrell Tomás, MA.; Agouram, S.; Torrecillas, R.; Fernandez, A. (2013). Microstructure and mechanical effects of spark plasma sintering in alumina monolithic ceramics. Scripta Materialia. 68(8):603-606. https://doi.org/10.1016/j.scriptamat.2012.12.016S60360668

Long-term prognosis for 1-year relapse-free survivors of CD34 cell-selected allogeneic hematopoietic stem cell transplantation : a landmark analysis

Altres ajuts: This research was supported in part by National Institutes of Health award number P01 CA23766 and NIH/NCI Cancer Center Support Grant P30 CA008748. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.CD34 selection significantly improves GVHD-free survival in allogeneic hematopoietic cell transplantation (allo-HSCT). Specific information regarding long-term prognosis and risk factors for late mortality after CD34-selected allo-HSCT is lacking, however. We conducted a single-center landmark analysis in 276 patients alive without relapse 1 year after CD34-selected allo-HSCT for AML (n=164), ALL (n=33), or MDS (n=79). At 5 years' follow-up after the 1-year landmark (range 0.03-13 years), estimated RFS was 73% and OS 76%. The 5-year cumulative incidence of relapse and NRM were 11% and 16%, respectively. In multivariate analysis, HCT-CI score ≥ 3 correlated with marginally worse RFS (HR 1.78, 95% CI 0.97-3.28, p=0.06) and significantly worse OS (HR 2.53, 95% CI 1.26-5.08, p=0.004). Despite only 24% of patients with acute GVHD within 1 year, this also significantly correlated with worse RFS and OS, with increasing grades of acute GVHD associating with increasingly poorer survival on multivariate analysis (p<0.0001). Of 63 deaths after the landmark, GVHD accounted for 27% of deaths and was the most common cause of late mortality, followed by relapse and infection. While prognosis is excellent for patients alive without relapse 1 year after CD34-selected allo-HSCT, risks of late relapse and NRM persist, particularly due to GVHD