59,996 research outputs found
Abstract Tensor Systems as Monoidal Categories
The primary contribution of this paper is to give a formal, categorical
treatment to Penrose's abstract tensor notation, in the context of traced
symmetric monoidal categories. To do so, we introduce a typed, sum-free version
of an abstract tensor system and demonstrate the construction of its associated
category. We then show that the associated category of the free abstract tensor
system is in fact the free traced symmetric monoidal category on a monoidal
signature. A notable consequence of this result is a simple proof for the
soundness and completeness of the diagrammatic language for traced symmetric
monoidal categories.Comment: Dedicated to Joachim Lambek on the occasion of his 90th birthda
The Infrared Nucleus of the Wolf-Rayet Galaxy Henize 2-10
We have obtained near-infrared images and mid-infrared spectra of the
starburst core of the dwarf Wolf-Rayet galaxy He 2-10. We find that the
infrared continuum and emission lines are concentrated in a flattened ellipse
3-4'' or 150 pc across which may show where a recent accretion event has
triggered intense star formation. The ionizing radiation from this cluster has
an effective temperature of 40,000 K, corresponding to stars, and
the starburst is years old.Comment: 17 pages Latex, 7 postscript figures, 1 postscript table, accepted to
A
What Drives Car Attitudes: An Analysis of How Demographics and Environmental Views Relate to Car Attitudes
Successfully marketing new, clean, car technologies to consumers requires an advertising strategy that fits consumersâ priorities and attitudes towards cars. We created a survey to study how attitudes towards cars are associated with demographics and environmental views. Our study examined car preferences and environmental concerns of a sample of Gettysburg College students in comparison to a national sample obtained from Amazonâs Mechanical Turk. Overall, we concluded that environmental beliefs are a significantly better prediction of car behaviors than demographics. We found that on average people would pay more for a car with a higher fuel economy, but not enough to cover the higher price of newer, cleaner technologies, such as hybrid cars. Gettysburg College studentsâ environmental concern scores were significantly higher on average than that of the general American population. Survey respondents from both samples supported devoting more research and resources to hybrid, electric, and biofuel technologies. However, in regards to their personal purchases they ranked safety and other qualities of the car as higher priorities than greenhouse gas emissions or fuel economy. According to our results, marketing electric cars as safe and reliable is a better strategy than marketing their high fuel economy
Quasi-elastic neutrino charged-current scattering cross sections on oxygen
The charged-current quasi-elastic scattering of muon neutrinos on oxygen
target is computed for neutrino energies between 200 MeV and 2.5 GeV using the
relativistic distorted-wave impulse approximation with relativistic optical
potential, which was earlier successfully applied to describe electron-nucleus
data. We study both neutrino and electron processes and show that the reduced
exclusive cross sections for neutrino and electron scattering are similar. The
comparison with the relativistic Fermi gas model (RFGM), which is widely used
in data analyses of neutrino experiments, shows that the RFGM fails completely
when applied to exclusive cross section data and leads to overestimated values
of inclusive and total cross sections. We also found significant nuclear-model
dependence of exclusive, inclusive and total cross sections for about 1 GeV
energy.Comment: 30 pages, 11 figures; final version to appear in Phys. Rev.
BĂŒchwald-Hartwig reaction applied to synthesis of new luminescent liquid crystal triarylamines derived from isoxazoles
© 2015 Taylor & Francis Group, LLC. The present work describes the synthesis and characterization of novel series of triarylamines isoxazoles (TAA) addressed to the organic photovoltaic materials. Diarylisoxazoles were synthesized by sequential [3+2] 1,3-dipolar cycloaddition reaction between arylnitrile oxides and selected arylalkenes followed by MnO2-oxidation. Isoxazoles were coupled to diarylamines by BĂŒchwald-Hartwig reaction to afford desired compounds 6a-k. Some TAA display liquid-crystalline behaviour and UV-Vis absorption and fluorescence emission were analysed for all samples of TAA 6a-k
Neutrons transition densities for the multiplet of states in Zr
The neutron transition densities of the levels in Zr were
extracted in the process of analysing ({\bf p},p') scattering at 400 Mev. Its
comparison with the proton transition densities for these levels was
undertaken. The radial shapes of the experimental neutron and proton transition
densities for each state were found to be different.Comment: 9 pages, 4 figure
Microwave oven fabricated hybrid memristor devices for non-volatile memory storage
© 2014 IOP Publishing Ltd. Novel hybrid non-volatile memories made using an ultra-fast microwave heating method are reported for the first time. The devices, consisting of aligned ZnO nanorods embedded in poly (methyl methacrylate), require no forming step and exhibit reliable and reproducible bipolar resistive switching at low voltages and with low power usage. We attribute these properties to a combination of the high aspect ratio of the nanorods and the polymeric hybrid structure of the device. The extremely easy, fast and low-cost solution based method of fabrication makes possible the simple and quick production of cheap memory cells
T-Cell Subsets Predict Mortality in Malnourished Zambian Adults Initiating Antiretroviral Therapy.
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedTo estimate the prognostic value of T-cell subsets in Zambian patients initiating antiretroviral therapy (ART), and to assess the impact of a nutritional intervention on T-cell subsets.This work was supported by European and Developing Countries Clinical Trials Partnership grant # IP.2009.33011.004; trial foods were prepared and supplied by Nutriset, Malauney, Franc
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