A mixed-mode shell-model theory for nuclear structure studies

We introduce a shell-model theory that combines traditional spherical states, which yield a diagonal representation of the usual single-particle interaction, with collective configurations that track deformations, and test the validity of this mixed-mode, oblique basis shell-model scheme on $^{24}$Mg. The correct binding energy (within 2% of the full-space result) as well as low-energy configurations that have greater than 90% overlap with full-space results are obtained in a space that spans less than 10% of the full space. The results suggest that a mixed-mode shell-model theory may be useful in situations where competing degrees of freedom dominate the dynamics and full-space calculations are not feasible.Comment: 20 pages, 8 figures, revtex 12p

Mimesis stories: composing new nature music for the shakuhachi

Nature is a widespread theme in much new music for the shakuhachi (Japanese bamboo flute). This article explores the significance of such music within the contemporary shakuhachi scene, as the instrument travels internationally and so becomes rooted in landscapes outside Japan, taking on the voices of new creatures and natural phenomena. The article tells the stories of five compositions and one arrangement by non-Japanese composers, first to credit composers’ varied and personal responses to this common concern and, second, to discern broad, culturally syncretic traditions of nature mimesis and other, more abstract, ideas about the naturalness of sounds and creative processes (which I call musical naturalism). Setting these personal stories and longer histories side by side reveals that composition creates composers (as much as the other way around). Thus it hints at much broader terrain: the refashioning of human nature at the confluence between cosmopolitan cultural circulations and contemporary encounters with the more-than-human world

Kondo effect in the Kohn-Sham conductance of multiple levels quantum dots

At zero temperature, the Landauer formalism combined with static density functional theory is able to correctly reproduce the Kondo plateau in the conductance of the Anderson impurity model provided that an exchange-correlation potential is used which correctly exhibits steps at integer occupation. Here we extend this recent finding to multi-level quantum dots described by the constant-interaction model. We derive the exact exchange-correlation potential in this model for the isolated dot and deduce an accurate approximation for the case when the dot is weakly coupled to two leads. We show that at zero temperature and for non-degenerate levels in the dot we correctly obtain the conductance plateau for any odd number of electrons on the dot. We also analyze the case when some of the levels of the dot are degenerate and again obtain good qualitative agreement with results obtained with alternative methods. As in the case of a single level, for temperatures larger than the Kondo temperature, the Kohn-Sham conductance fails to reproduce the typical Coulomb blockade peaks. This is attributed to {\em dynamical} exchange-correlation corrections to the conductance originating from time-dependent density functional theory.Comment: 8 pages, 4 figures, submitted to special issue of pss(b

Mode-hop-free tuning over 135 GHz of external cavity diode lasers without anti-reflection coating

We report an external cavity diode laser (ECDL), using a diode whose front facet is not antireflection (AR) coated, that has a mode-hop-free (MHF) tuning range greater than 135 GHz. We achieved this using a short external cavity and by simultaneously tuning the internal and external modes of the laser. We find that the precise location of the pivot point of the grating in our laser is less critical than commonly believed. The general applicability of the method, combined with the compact portable mechanical and electronic design, makes it well suited for both research and industrial applications.Comment: 5 pages, 5 figure

Oro, plata y mercurio, nervios de la monarquía de España

Editada en la Fundación Empresa PúblicaEl carácter distintivo de la monarquía española durante toda la Edad Moderna fue el dominio de las principales zonas del planeta productoras de plata y mercurio, lo que le proporcionó una ventaja monetaria comparativa prácticamente inexpugnable, especialmente durante el período de siglo y medio que siguió a la introducción del patrón-plata en la China de los Ming, en que la relación bimetálica plata/oro resultó extremadamente favorable para la plata. Esto permitió que el poder imperial descansase sobre una combinación sencilla de políticas extractivas, logísticas y financieras, cuyo indicador privilegiado es el mercado del azogue, que se reconstruye en este trabajo.The distinctive character of the Spanish monarchy all along the modern age was the domination on the main producing zones of silver and mercury in the planet, which provided practically uncontestable a comparative monetary advantage to her, specially during the period of century and a half following the introduction of the silver-standard in the Ming's China, during which the bimetallic relation was extremely favorable for the silver. This allowed the imperial power to rest on an very simple combination of extractive, logistic and fínancial policies, whose privileged indicator is the market of the mercury, that reconstructs in this work.Publicad

Phonon-induced spin relaxation of conduction electrons in aluminum

Spin-flip Eliashberg function $\alpha_S^2F$ and temperature-dependent spin relaxation time $T_1(T)$ are calculated for aluminum using realistic pseudopotentials. The spin-flip electron-phonon coupling constant $\lambda_S$ is found to be $2.5\times 10^{-5}$. The calculations agree with experiments validating the Elliott-Yafet theory and the spin-hot-spot picture of spin relaxation for polyvalent metals.Comment: 4 pages; submitted to PR

Modulation of potassium channels inhibits bunyavirus infection

Bunyaviruses are considered to be emerging pathogens facilitated by the segmented nature of their genome that allows reassortment between different species to generate novel viruses with altered pathogenicity. Bunyaviruses are transmitted via a diverse range of arthropod vectors, as well as rodents, and have established a global disease range with massive importance in healthcare, animal welfare and economics. There are no vaccines or anti-viral therapies available to treat human bunyavirus infections and so development of new anti-viral strategies is urgently required. Bunyamwera virus (BUNV; genus Orthobunyavirus) is the model bunyavirus, sharing aspects of its molecular and cellular biology with all Bunyaviridae family members. Here, we show for the first time that BUNV activates and requires cellular potassium (K+) channels to infect cells. Time of addition assays using K+ channel modulating agents demonstrated that K+ channel function is critical to events shortly after virus entry but prior to viral RNA synthesis/replication. A similar K+ channel dependence was identified for other bunyaviruses namely Schmallenberg virus (Orthobunyavirus) as well as the more distantly related Hazara virus (Nairovirus). Using a rational pharmacological screening regimen, twin-pore domain K+ channels (K2P) were identified as the K+ channel family mediating BUNV K+ channel dependence. As several K2P channel modulators are currently in clinical use, our work suggests they may represent a new and safe drug class for the treatment of potentially lethal bunyavirus disease

Costimulation blockade with Belatacept in renal transplantation

Background: Renal transplantation is the standard of care for patients with end-stage renal disease. Although maintenance immunosuppression with calcineurin inhibitors yields excellent one-year survival, it is associated over the long term with high rates of death and graft loss, owing in part to the adverse renal, cardiovascular, and metabolic effects of these agents. The use of potentially less toxic agents, such as belatacept, a selective blocker of T-cell activation, may improve outcomes. Methods: We randomly assigned renal-transplant recipients to receive an intensive or a less-intensive regimen of belatacept or cyclosporine. All patients received induction therapy with basiliximab, mycophenolate mofetil, and corticosteroids. The primary objective was to demonstrate the noninferiority of belatacept over cyclosporine in the incidence of acute rejection at six months (with an upper bound of the 95 percent confidence interval around the treatment difference of less than 20 percent). Results: At six months, the incidence of acute rejection was similar among the groups: 7 percent for intensive belatacept, 6 percent for less-intensive belatacept, and 8 percent for cyclosporine. At 12 months, the glomerular filtration rate was significantly higher with both intensive and less-intensive belatacept than it was with cyclosporine (66.3, 62.1, and 53.5 ml per minute per 1.73 m2, respectively), and chronic allograft nephropathy was less common with both regimens of belatacept than with cyclosporine (29 percent, 20 percent, and 44 percent, respectively). Lipid levels and blood-pressure values were similar or slightly lower in the belatacept groups, despite the greater use of lipid-lowering and antihypertensive medications in the cyclosporine group. Conclusions: Belatacept, an investigational selective costimulation blocker, did not appear to be inferior to cyclosporine as a means of preventing acute rejection after renal transplantation. Belatacept may preserve the glomerular filtration rate and reduce the rate of chronic allograft nephropathy