Distributed Radiation Monitoring System for Linear Accelerators based on CAN Bus

Abstract—Gamma and neutron radiation is produced during the normal operation of linear accelerators like Free-Electron Laser in Hamburg (FLASH) or X-ray Free Electron Laser (X-FEL). Gamma radiation cause general degeneration of electronics devices and neutron fluence can be a reason of soft error in memories and microcontrollers. X-FEL accelerator will be built only in one tunnel, therefore most of electronic control systems will be placed in radiation environment. Exposing control systems to radiation may lead to many errors and unexpected failure of the whole accelerator system. Thus, the radiation monitoring system able to monitor radiation doses produced near controlling systems is crucial. Knowledge of produced radiation doses allows to detect errors caused by radiation, make plans of essential exchange of control systems and prevent accelerator from serious damages. The paper presents the project of radiation monitoring system able to monitor radiation environment in real time

Spin dynamics in a Curie-switch

Ferromagnetic resonance properties of F$_1$/f/F$_2$/AF multilayers, where weakly ferromagnetic spacer f is sandwiched between strongly ferromagnetic layers F$_1$ and F$_2$, with F$_1$ being magnetically soft and F$_2$ - magnetically hard due to exchange pinning to antiferromagnetic layer AF, are investigated. Spacer-mediated exchange coupling is shown to strongly affect the resonance fields of both F$_1$ and F$_2$ layers. Our theoretical calculations as well as measurements show that the key magnetic parameters of the spacer, which govern the ferromagnetic resonance in F$_1$/f/F$_2$/AF, are the magnetic exchange length ($\Lambda$), effective saturation magnetization at $T=0$ $(m_0)$, and effective Curie temperature ($T_{\text{C}}^{\text{eff}}$). The values of these key parameters are deduced from the experimental data for multilayers with f = Ni$_x$Cu$_{100-x}$, for the key ranges in Ni-concentration ($x=54\div70$ at. %) and spacer thickness ($d=3\div 6$ nm). The results obtained provide a deeper insight into thermally-controlled spin precession and switching in magnetic nanostructures, with potential applications in spin-based oscillators and memory devices.Comment: 9 pages, 7 figures, 24 reference

Design of an electrochemical micromachining machine

Electrochemical micromachining (μECM) is a non-conventional machining process based on the phenomenon of electrolysis. μECM became an attractive area of research due to the fact that this process does not create any defective layer after machining and that there is a growing demand for better surface integrity on different micro applications including microfluidics systems, stress-free drilled holes in automotive and aerospace manufacturing with complex shapes, etc. This work presents the design of a next generation μECM machine for the automotive, aerospace, medical and metrology sectors. It has three axes of motion (X, Y, Z) and a spindle allowing the tool-electrode to rotate during machining. The linear slides for each axis use air bearings with linear DC brushless motors and 2-nm resolution encoders for ultra precise motion. The control system is based on the Power PMAC motion controller from Delta Tau. The electrolyte tank is located at the rear of the machine and allows the electrolyte to be changed quickly. This machine features two process control algorithms: fuzzy logic control and adaptive feed rate. A self-developed pulse generator has been mounted and interfaced with the machine and a wire ECM grinding device has been added. The pulse generator has the possibility to reverse the pulse polarity for on-line tool fabrication.The research reported in this paper is supported by the European Commission within the project “Minimizing Defects in Micro-Manufacturing Applications (MIDEMMA)” (FP7-2011-NMPICT- FoF-285614)

Proceso de diseño del Centro de Interpretación Cañadón del Duraznillo, Golfo San Jorge, Santa Cruz, Argentina

Este trabajo examina el proceso de diseño del Centro de Interpretación Cañadón del Duraznillo, ubicado en el Golfo San Jorge, Santa Cruz, Argentina. Desde los primeros esbozos morfológicos hasta la selección de materiales y detalles constructivos, dicho proceso fue guiado por simulaciones y estudios de las condiciones ambientales específicas a este caso particular, como así también recomendaciones generales apropiadas para este clima y localización geográfica a partir de bibliografía especializada y experiencias proyectuales anteriores. Los estudios desarrollados incluyeron simulaciones de asoleamiento, radiación solar, viento, iluminación natural y características térmicas de los materiales de la envolvente. El objetivo de este artículo es presentar un caso específico de arquitectura de bajo impacto ambiental y alto grado de eficiencia energética y examinar la productividad metodológica del diseño arquitectónico asistido por estudios en un laboratorio de estudios bioambientales.Fil: Kozak, Daniel Matias. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Saavedra 15. Centro de Estudios Urbanos y Regionales; ArgentinaFil: de Schiller, S.. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo. Centro de Investigacion Habitat y Energia; ArgentinaFil: Evans, J. M.. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo. Centro de Investigacion Habitat y Energia; ArgentinaFil: Adamo, G.. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo. Centro de Investigacion Habitat y Energia; ArgentinaFil: Abálsamo, D.. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo. Centro de Investigacion Habitat y Energia; Argentin

Identification of genes expressed by immune cells of the colon that are regulated by colorectal cancer-associated variants.

A locus on human chromosome 11q23 tagged by marker rs3802842 was associated with colorectal cancer (CRC) in a genome-wide association study; this finding has been replicated in case-control studies worldwide. In order to identify biologic factors at this locus that are related to the etiopathology of CRC, we used microarray-based target selection methods, coupled to next-generation sequencing, to study 103 kb at the 11q23 locus. We genotyped 369 putative variants from 1,030 patients with CRC (cases) and 1,061 individuals without CRC (controls) from the Ontario Familial Colorectal Cancer Registry. Two previously uncharacterized genes, COLCA1 and COLCA2, were found to be co-regulated genes that are transcribed from opposite strands. Expression levels of COLCA1 and COLCA2 transcripts correlate with rs3802842 genotypes. In colon tissues, COLCA1 co-localizes with crystalloid granules of eosinophils and granular organelles of mast cells, neutrophils, macrophages, dendritic cells and differentiated myeloid-derived cell lines. COLCA2 is present in the cytoplasm of normal epithelial, immune and other cell lineages, as well as tumor cells. Tissue microarray analysis demonstrates the association of rs3802842 with lymphocyte density in the lamina propria (p = 0.014) and levels of COLCA1 in the lamina propria (p = 0.00016) and COLCA2 (tumor cells, p = 0.0041 and lamina propria, p = 6 × 10(-5)). In conclusion, genetic, expression and immunohistochemical data implicate COLCA1 and COLCA2 in the pathogenesis of colon cancer. Histologic analyses indicate the involvement of immune pathways

The Dressing Factor and Crossing Equations

We utilize the DHM integral representation for the BES dressing factor of the world-sheet S-matrix of the AdS_5xS^5 light-cone string theory, and the crossing equations to fix the principal branch of the dressing factor on the rapidity torus. The results obtained are further used, in conjunction with the fusion procedure, to determine the bound state dressing factor of the mirror theory. We convincingly demonstrate that the mirror bound state S-matrix found in this way does not depend on the internal structure of a bound state solution employed in the fusion procedure. This welcome feature is in perfect parallel to string theory, where the corresponding bound state S-matrix has no bearing on bound state constituent particles as well. The mirror bound state S-matrix we found provides the final missing piece in setting up the TBA equations for the AdS_5xS^5 mirror theory.Comment: LaTex, 48 pages, 10 figures; v2: a new section added where the dressing factor of the mirror theory is found; v3: formula (6.12) is corrected, a new figure is added, accepted for publication in J.Phys.

Structural Stability of Intelectin-1

We study the structural stability of helical and non-helical regions in chain A of human intelectin-1. Using a geometrical model introduced previously, a computational analysis based on the recently reported crystal structure of this protein by Kiessling et al. [Nature Struct. Mole. Bio. 22 (2015), 603] is carried out to quantify the resiliency of the native state to steric perturbations. Response to these perturbations is characterized by calculating, relative to the native state, the lateral, radial and angular displacements of n-residue segments of the polypeptide chain centered on each residue. By quantifying the stability of the protein through six stages of unfolding, we are able to identify regions in chain A of intelectin-1 which are markedly affected by structural perturbations versus those which are relatively unaffected, the latter suggesting that the native-state geometry of these regions is essentially conserved. Importantly, residues in the vicinity of calcium ions comprise a conserved region, suggesting that Ca ions play a role not only in the coordination of carbohydrate hydroxyl groups, but in preserving the integrity of the structure