30 research outputs found
Projective superspace and hyperkahler sigma models on cotangent bundles of Hermitian symmetric spaces
We review the projective-superspace construction of four-dimensional N=2
supersymmetric sigma models on (co)tangent bundles of the classical Hermitian
symmetric spaces.Comment: 4 pages. Contribution to the proceedings of PASCOS-07, 2-7 July 2007,
Imperial College, Londo
Recent developments with the new tools for collimation simulations in Xsuite
Simulations of single-particle tracking involving collimation systems need dedicated tools to perform the different tasks needed. These include the accurate description of particle-matter interactions when a tracked particle impacts a collimator jaw; a detailed aperture model to identify the longitudinal location of losses; and others. One such tool is the K2 code in SixTrack, which describes the scattering of high-energy protons in matter. This code has recently been ported into the Xsuite tracking code that is being developed at CERN. Another approach is to couple the tracking with existing tools, such as FLUKA or Geant4, that offer better descriptions of particle-matter interactions and can treat lepton and ion beams. This includes the generation of secondary particles and fragmentation when tracking ions. In addition to the development of coupling with Geant4, the SixTrack-FLUKA coupling has recently been translated and integrated into the Xsuite environment as well. In this paper, we present the ongoing development of these tools. A thorough testing of the new implementation was performed, using as case studies various collimation layout configurations for the LHC Run 3
The Influence of Age and Sex on Genetic Associations with Adult Body Size and Shape : a Large-Scale Genome-Wide Interaction Study
Genome-wide association studies (GWAS) have identified more than 100 genetic variants contributing to BMI, a measure of body size, or waist-to-hip ratio (adjusted for BMI, WHRadjBMI), a measure of body shape. Body size and shape change as people grow older and these changes differ substantially between men and women. To systematically screen for age- and/or sex-specific effects of genetic variants on BMI and WHRadjBMI, we performed meta-analyses of 114 studies (up to 320,485 individuals of European descent) with genome-wide chip and/or Metabochip data by the Genetic Investigation of Anthropometric Traits (GIANT) Consortium. Each study tested the association of up to ~2.8M SNPs with BMI and WHRadjBMI in four strata (men ≤50y, men >50y, women ≤50y, women >50y) and summary statistics were combined in stratum-specific meta-analyses. We then screened for variants that showed age-specific effects (G x AGE), sex-specific effects (G x SEX) or age-specific effects that differed between men and women (G x AGE x SEX). For BMI, we identified 15 loci (11 previously established for main effects, four novel) that showed significant (FDR<5%) age-specific effects, of which 11 had larger effects in younger (<50y) than in older adults (≥50y). No sex-dependent effects were identified for BMI. For WHRadjBMI, we identified 44 loci (27 previously established for main effects, 17 novel) with sex-specific effects, of which 28 showed larger effects in women than in men, five showed larger effects in men than in women, and 11 showed opposite effects between sexes. No age-dependent effects were identified for WHRadjBMI. This is the first genome-wide interaction meta-analysis to report convincing evidence of age-dependent genetic effects on BMI. In addition, we confirm the sex-specificity of genetic effects on WHRadjBMI. These results may provide further insights into the biology that underlies weight change with age or the sexually dimorphism of body shape
Adsorption and Electrodeposition on SnO[sub 2] and WO[sub 3] Electrodes in 1 M LiClO[sub 4]PC In Situ Light Scattering and In Situ Atomic Force Microscopy Studies
Electrostatic Deposition of the Oxidized Kraft Lignin onto the Surface of Aminosilicas: Thermal and Structural Characteristics of Hybrid Materials
In recent years, functional polymeric compounds have
been widely
used to modify the silica surface, which allows one to obtain the
corresponding organomineral composites for broad application prospects.
In this case, lignina cross-linked polyphenolic macromoleculeis
of great interest according to its valuable properties and possible
surplus as a by-product of pulp and paper industry and various biorefinery
processes. Hybrid materials based on kraft softwood lignin and silica
were obtained via the electrostatic attraction of oxidized lignin
to the aminosilica surface with different porosities, which were prepared
by the amination of the commercial silica gel with an average pore
diameter of 6 nm, and the silica prepared in the lab with the oxidized
kraft lignin and lignin–silica samples with an average pore
diameter of 38 nm was investigated by physicochemical methods: two-dimensional
nuclear magnetic resonance (NMR), 31P NMR, Fourier transform
infrared spectroscopy, thermogravimetric analysis in nitrogen and
air atmosphere, scanning electron microscopy, and adsorption methods.
After oxidation, the content of carboxylic groups almost doubled in
the oxidized lignin, compared to that in the native one (0.74 mmol/g
against 0.44 mmol/g, respectively). The lignin content was deposited
onto the surface of aminosilica, depending on the porosity of the
silica material and on the content of amino groups on its surface,
giving lignin–aminosilica with 20% higher lignin content than
the lignin–aminosilica gel. Both types of lignin–silica
composites demonstrate a high sorptive capacity toward crystal violet
dye. The suggested approach is an easy and low-cost way of synthesis
of lignin–silica composites with unique properties. Such composites
have a great potential for use as adsorbents in wastewater treatment
processes
Understanding the Dispersive Action of Nanocellulose for Carbon Nanomaterials
This work aims at understanding the
excellent ability of nanocelluloses to disperse carbon nanomaterials
(CNs) in aqueous media to form long-term stable colloidal dispersions
without the need for chemical functionalization of the CNs or the
use of surfactant. These dispersions are useful for composites with
high CN content when seeking water-based, efficient, and green pathways
for their preparation. To establish a comprehensive understanding
of such dispersion mechanism, colloidal characterization of the dispersions
has been combined with surface adhesion measurements using colloidal
probe atomic force microscopy (AFM) in aqueous media. AFM results
based on model surfaces of graphene and nanocellulose further suggest
that there is an association between the nanocellulose and the CN.
This association is caused by fluctuations of the counterions on the
surface of the nanocellulose inducing dipoles in the sp<sup>2</sup> carbon lattice surface of the CNs. Furthermore, the charges on the
nanocellulose will induce an electrostatic stabilization of the nanocellulose–CN
complexes that prevents aggregation. On the basis of this understanding,
nanocelluloses with high surface charge density were used to disperse
and stabilize carbon nanotubes (CNTs) and reduced graphene oxide
particles in water, so that further increases in the dispersion limit
of CNTs could be obtained. The dispersion limit reached the value
of 75 wt % CNTs and resulted in high electrical conductivity (515
S/cm) and high modulus (14 GPa) of the CNT composite nanopapers
Health Impacts of Nonmotorized Travel, Telecommuting, and the Built Environment: A County-Level Analysis
Salutogenesis Post-Graduate Education: Experience From the European Perspective on the ETC-PHHP Health Promotion Summer Schools (1991-2020)
In this chapter, the authors, representing The Netherlands, Spain, Germany, Italy, Norway, the United Kingdom and Poland, trace the development of higher education in salutogenesis in Europe, spanning 30 years. At this time, the annual summer schools of the European Training Consortium in Public Health and Health Promotion (ETC-PHHP) have trained more than 700 participants from 60 countries. Perhaps the most distinguished member of the summer school’s faculty - at least from the perspective of advancing salutogenesis as a theory for health promotion - is Aaron Antonovsky, who participated in the 1992 edition of the course in Gothenburg, Sweden
