Fourth virial coefficients of asymmetric nonadditive hard-disc mixtures

The fourth virial coefficient of asymmetric nonadditive binary mixtures of hard disks is computed with a standard Monte Carlo method. Wide ranges of size ratio ($0.05\leq q\leq 0.95$) and nonadditivity ($-0.5\leq \Delta\leq 0.5$) are covered. A comparison is made between the numerical results and those that follow from some theoretical developments. The possible use of these data in the derivation of new equations of state for these mixtures is illustrated by considering a rescaled virial expansion truncated to fourth order. The numerical results obtained using this equation of state are compared with Monte Carlo simulation data in the case of a size ratio $q=0.7$ and two nonadditivities $\Delta=\pm 0.2$.Comment: 9 pages, 7 figures; v2: section on equation of state added; tables moved to supplementary material (http://jcp.aip.org/resource/1/jcpsa6/v136/i18/p184505_s1#artObjSF

Los Papiros de Herculano en la España de finales del siglo XVIII y comienzos del XIX

The aim of this article is to explore the interest aroused by the Herculaneum papyri among Spanish intellectuals in the 18th and 19th centuries. For this purpose, the authors draw on the testimony of travellers, scholars and prominent writers like Francisco Pérez Báyer, Nicolás de Azara, Esteban de Arteaga, Leandro Fernández de Moratín, Pedro Antonio de Alarcón, Pedro Montengón and Juan Andrés y Morell. While the first five writers reflect upon the topic in a general manner, Montegón and Andrés do deal with it in greater detail

Thermal decomposition of single hydroxychlorides of nickel, copper and cobalto

The thermal decomposition reactions of Ni(OH)Cl.l½H20 in still air and in nitrogen and β-CO2(OH)3Cl and γ-Cu2(OH)3Cl in nitrogen atmosphere, have been studied by DTA and TG analysis, and the intermediates and final products have been characterized by x-ray diffraction and infrared spectroscop. The thermal evolution ot the above indicated compounds under dynamic vacuum conditions has be en studied with the aid of an x-ray high teaperature diffraction chamber. They reveals that in these conditions, the pure metallic nickel, copper and cobalt can be obtained at comparative low temperature. The infrared spectra of thése hydroxychlorides have been tentatively assigned

Experiencies in obtaining polymeric composites reinforced with natural fiber from Ecuador

Esta revisión presenta los reportes de las investigaciones relacionadas con el desarrollo de nuevos materiales compuestos poliméricos reforzados con fibras naturales y desechos agroindustriales provenientes del Ecuador. Se analizan las fibras vegetales con potencial para ser empleadas como reforzante en compuestos poliméricos. Se sintetizan los resultados relevantes de las diferentes investigaciones analizadas. Aspectos como el tipo de matriz, la morfología de las fibras, los tratamientos superficiales y las propiedades mecánicas son presentados.This review presents the research reports related to the development of new polymeric composites reinforced with natural fibers and agro-industrial wastes from Ecuador. Vegetable fibers with potential are analyzed to be used as reinforcement in polymeric composites. It summarizes the relevant results from the different investigations analyzed. Aspects such as the type of matrix, the fiber morphology, surface treatment and mechanical properties are presented

Competing roles of DNA end resection and non-homologous end joining functions in the repair of replication-born double-strand breaks by sister-chromatid recombination

While regulating the choice between homologous recombination and non-homologous end joining (NHEJ) as mechanisms of double-strand break (DSB) repair is exerted at several steps, the key step is DNA end resection, which in Saccharomyces cerevisiae is controlled by the MRX complex and the Sgs1 DNA helicase or the Sae2 and Exo1 nucleases. To assay the role of DNA resection in sister-chromatid recombination (SCR) as the major repair mechanism of spontaneous DSBs, we used a circular minichromosome system for the repair of replication-born DSBs by SCR in yeast. We provide evidence that MRX, particularly its Mre11 nuclease activity, and Sae2 are required for SCR-mediated repair of DSBs. The phenotype of nuclease-deficient MRX mutants is suppressed by ablation of Yku70 or overexpression of Exo1, suggesting a competition between NHEJ and resection factors for DNA ends arising during replication. In addition, we observe partially redundant roles for Sgs1 and Exo1 in SCR, with a more prominent role for Sgs1. Using human U2OS cells, we also show that the competitive nature of these reactions is likely evolutionarily conserved. These results further our understanding of the role of DNA resection in repair of replication-born DSBs revealing unanticipated differences between these events and repair of enzymatically induced DSBs.Ministerio de Ciencia e Innovación BFU2006-05260, BFU2010-16372, CSD2007-015, SAF2010-21017, SAF2010-14877Junta de Andalucía BIO102, CVI4567European Community’s Seventh Framework Programme HEALTH-F2-2010-259893Cancer Research UK C6/A11224, C6946/A14492Wellcome Trust 09209

Virial series for fluids of hard hyperspheres in odd dimensions

A recently derived method [R. D. Rohrmann and A. Santos, Phys. Rev. E. {\bf 76}, 051202 (2007)] to obtain the exact solution of the Percus-Yevick equation for a fluid of hard spheres in (odd) $d$ dimensions is used to investigate the convergence properties of the resulting virial series. This is done both for the virial and compressibility routes, in which the virial coefficients $B_j$ are expressed in terms of the solution of a set of $(d-1)/2$ coupled algebraic equations which become nonlinear for $d \geq 5$. Results have been derived up to $d=13$. A confirmation of the alternating character of the series for $d\geq 5$, due to the existence of a branch point on the negative real axis, is found and the radius of convergence is explicitly determined for each dimension. The resulting scaled density per dimension $2 \eta^{1/d}$, where $\eta$ is the packing fraction, is wholly consistent with the limiting value of 1 for $d \to \infty$. Finally, the values for $B_j$ predicted by the virial and compressibility routes in the Percus-Yevick approximation are compared with the known exact values [N. Clisby and B. M. McCoy, J. Stat. Phys. {\bf 122}, 15 (2006)]Comment: 9 pages, 6 figure

Reparación del cartílago articular con injerto libre de pericondrio estudio experimental

Ante la incapacidad de regeneración espontánea de lesiones profundas y amplias del cartílago articular, estudiamos la reparación cartilaginosa con plastias de pericondrio tomadas de la región condro-costal e implantándolas con su cara condrogénica sobre una lesión osteocondral realizada en la superficie articular rotuliana. Macroscópica e histológicamente, a la octava semana, el neocartílago formado tenía igual apariencia que el cartílago hialino normal, no existiendo separación entre el cartílago remanente y el neoformado a partir de la plastia. Estos resultados corroboran el gran potencial condrogénico del pericondrioFaced with the incapacity of spontaneous regeneration of deep and extensive lesions of the articular cartilage we studied the cartilaginous repair with pericondrium grafts taken from the chondro-costal region. Grafts were implanted with their condrogenic face over an osteochondral defect located at the surface of the patella. At the 8th week, the neocartilage formed had macroscopically and histologically, the same appearance as the normal hyaline cartilage, with no separation between the remaining cartilage and the neocartilage induced by the graft. These results corroborate the high chondrogenic potential of the perichondrium

Structural and magnetic properties of Ni0.8Fe0.2/Ti nanoscale multilayers

The influence of the thickness of the Ni0.8Fe0.2 (Permalloy, Py) layers on the structural and magnetic properties of magnetron sputtered Py/Ti multilayers was studied. The thickness of the Py layers was varied in the interval of 8 to 30 Å. X-ray reflectivity scans evidence the existence of a well-defined layered structure in all the samples considered, but also the presence of a complex intermixed interface. The shape of both the temperature dependence of magnetization and the hysteresis loops of the multilayered structures depends strongly on Py thickness. Magnetic and reflectivity measurements were comparatively analyzed in order to better understand the structure of the samples, and specifically, their interfaces. In particular, the presence of small superparamagnetic Py at the interfaces of the samples, especially evident in the samples with the thinnest Py layers, seems confirmed by the magnetic measurements, agreeing well with the reflectivity results. © 2018 by the authors.1 Instituto Regional de Investigación Científica Aplicada (IRICA) and Departamento de Física Aplicada, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain; [email protected] (J.A.G.); [email protected] (J.P.A.) 2 Department of Solid State Magnetism, Institute of Natural Sciences and Mathematics, Ural Federal University, 620002 Ekaterinburg, Russia; [email protected] (A.V.S.); [email protected] (G.V.K.) 3 Departamento de Electricidad y Electrónica, Universidad del País Vasco (UPV/EHU), 48080 Bilbao, SpainFunding: The research was supported by the Ministry of Education and Science of the Russian Federation (Agreement no. 02.A03.21.0006) and by the Spanish projects MAT2014-58034-R (MINECO/AEI/FEDER, EU) and PEII-2014-042-P (JCCM/FEDER, EU)

Modeling the acquisition front-end in high resolution gamma-ray imaging

The availability of synthetic realistic data eases design optimization, algorithm evaluation and verification of any digital system where a significant amount of digital signal processing is performed. The evolution of positron emission tomography cameras towards continuous sampling of individual position-sensitive photomultiplier anodes with processing algorithms implemented on digital programmable logic devices creates a new framework where new approaches to the γ-event detection are possible. We have developed a system model of the acquisition chain, including multi-layer phoswich, photomultiplier, front-end analog electronics, data acquisition and digital processing. This processing includes estimation algorithms for the most relevant event parameters: energy, layer-of-interaction, time picking-off and event location. The selected simulation platform couples gently to digital hardware simulation tools, in such a way that implemented models may generate real-like stimuli for the digital system under development. The modeling of the whole front-end electronics enables deeper understanding and tuning of different system trade-offs and provides a rapid and soft transition between specification and hardware developmentPublicad