2,513 research outputs found
Full- Scale Load Test of Caisson on Chicago Hardpan
The results of a full-scale load test on a belled caisson bearing on hardpan in the downtown Chicago area are presented herein and are discussed in terms of current design practice and the results of other pertinent full-scale tests and a small-scale model test. Current specifications for allowable bearing pressures are shown to be conservative, and previously established settlement limits required to mobilize side resistance are reconfirmed. The settlement measured during the test is in good agreement with that predicted by use of pressuremeter test data. The confinement of the bell in a hard clay layer appears to be beneficial in that it serves to limit the development of major cracking at the base
Electromagnetic Calorimeter for HADES
We propose to build the Electromagnetic calorimeter for the HADES di-lepton
spectrometer. It will enable to measure the data on neutral meson production
from nucleus-nucleus collisions, which are essential for interpretation of
dilepton data, but are unknown in the energy range of planned experiments (2-10
GeV per nucleon). The calorimeter will improve the electron-hadron separation,
and will be used for detection of photons from strange resonances in elementary
and HI reactions.
Detailed description of the detector layout, the support structure, the
electronic readout and its performance studied via Monte Carlo simulations and
series of dedicated test experiments is presented.
The device will cover the total area of about 8 m^2 at polar angles between
12 and 45 degrees with almost full azimuthal coverage. The photon and electron
energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV])
which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in
Ni+Ni collisions at 8 AGeV. A purity of the identified leptons after the hadron
rejection, resulting from simulations based on the test measurements, is better
than 80% at momenta above 500 MeV/c, where time-of-flight cannot be used.Comment: 40 pages, 38 figures version2 - the time schedule added, information
about PMTs in Sec.III update
Picosecond transfer from short-term to long-term memory in analog antiferromagnetic memory device
Experiments in materials with a compensated ordering of magnetic moments have
demonstrated a potential for approaching the thermodynamic limit of the fastest
and least-dissipative operation of a digital memory bit. In addition, these
materials are very promising for a construction of energy-efficient analog
devices with neuromorphic functionalities, which are inspired by
computing-in-memory capabilities of the human brain. In this paper, we report
on experimental separation of switching-related and heat-related resistance
signal dynamics in memory devices microfabricated from CuMnAs antiferromagnetic
metal. We show that the memory variable multilevel resistance can be used as a
long-term memory (LTM), lasting up to minutes at room temperature. In addition,
ultrafast reflectivity change and heat dissipation from nanoscale-thickness
CuMnAs films, taking place on picosecond to hundreds of nanoseconds time
scales, can be used as a short-term memory (STM). Information about input
stimuli, represented by femtosecond laser pulses, can be transferred from STM
to LTM after rehearsals at picosecond to nanosecond times in these memory
devices, where information can be retrieved at times up to 10^15 longer than
the input pulse duration. Our results open a route towards ultra-fast low-power
implementations of spiking neuron and synapse functionalities using a resistive
analog antiferromagnetic memory.Comment: 21 pages, 4 figure
'Working out’ identity: distance runners and the management of disrupted identity
This article contributes fresh perspectives to the empirical literature on the sociology of the body, and of leisure and identity, by analysing the impact of long-term injury on the identities of two amateur but serious middle/long-distance runners. Employing a symbolic interactionist framework,and utilising data derived from a collaborative autoethnographic project, it explores the role
of ‘identity work’ in providing continuity of identity during the liminality of long-term injury and
rehabilitation, which poses a fundamental challenge to athletic identity. Specifically, the analysis
applies Snow and Anderson’s (1995) and Perinbanayagam’s (2000) theoretical conceptualisations
in order to examine the various forms of identity work undertaken by the injured participants, along
the dimensions of materialistic, associative and vocabularic identifications. Such identity work was
found to be crucial in sustaining a credible sporting identity in the face of disruption to the running
self, and in generating momentum towards the goal of restitution to full running fitness and reengagement
with a cherished form of leisure.
KEYWORDS: identity work, symbolic interactionism, distance running, disrupted identit
Aintegumenta and Aintegumenta-Like6 regulate auxin-mediated flower development in Arabidopsis
<p>Abstract</p> <p>Background</p> <p>Two related genes encoding AP2/ERF-type transcription factors, <it>AINTEGUMENTA </it>(<it>ANT</it>) and <it>AINTEGUMENTA-LIKE6 </it>(<it>AIL6</it>), are important regulators of floral growth and patterning in Arabidopsis. Evidence suggests that these genes promote several aspects of flower development in response to auxin. To investigate the interplay of <it>ANT</it>, <it>AIL6 </it>and auxin during floral development, I have examined the phenotypic consequences of disrupting polar auxin transport in <it>ant</it>, <it>ail6 </it>and <it>ant ail6 </it>mutants by either genetic or chemical means.</p> <p>Results</p> <p>Plants containing mutations in <it>ANT </it>or <it>AIL6 </it>alone or in both genes together exhibit increased sensitivity to disruptions in polar auxin transport. Both genes promote shoot growth, floral meristem initiation and floral meristem patterning in combination with auxin transport. However, differences in the responses of <it>ant </it>and <it>ail6 </it>single mutants to perturbations in auxin transport suggest that these two genes also have non-overlapping activities in each of these developmental processes.</p> <p>Conclusions</p> <p>The enhanced sensitivity of <it>ant </it>and <it>ail6 </it>mutants to alterations in polar auxin transport suggests that these mutants have defects in some aspect of auxin physiology. The inability of <it>ant ail6 </it>double mutants to initiate flowers in backgrounds disrupted for auxin transport confirm the proposed roles for these two genes in floral meristem initiation.</p
Nuclear matter effects on production in asymmetric Cu+Au collisions at = 200 GeV
We report on production from asymmetric Cu+Au heavy-ion collisions
at =200 GeV at the Relativistic Heavy Ion Collider at both
forward (Cu-going direction) and backward (Au-going direction) rapidities. The
nuclear modification of yields in CuAu collisions in the Au-going
direction is found to be comparable to that in AuAu collisions when plotted
as a function of the number of participating nucleons. In the Cu-going
direction, production shows a stronger suppression. This difference is
comparable in magnitude and has the same sign as the difference expected from
shadowing effects due to stronger low- gluon suppression in the larger Au
nucleus. The relative suppression is opposite to that expected from hot nuclear
matter dissociation, since a higher energy density is expected in the Au-going
direction.Comment: 349 authors, 10 pages, 4 figures, and 4 tables. Submitted to Phys.
Rev. C. For v2, fixed LaTeX error in 3rd-to-last sentence. Plain text data
tables for the points plotted in figures for this and previous PHENIX
publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
Measurement of higher cumulants of net-charge multiplicity distributions in AuAu collisions at GeV
We report the measurement of cumulants () of the net-charge
distributions measured within pseudorapidity () in AuAu
collisions at GeV with the PHENIX experiment at the
Relativistic Heavy Ion Collider. The ratios of cumulants (e.g. ,
) of the net-charge distributions, which can be related to volume
independent susceptibility ratios, are studied as a function of centrality and
energy. These quantities are important to understand the quantum-chromodynamics
phase diagram and possible existence of a critical end point. The measured
values are very well described by expectation from negative binomial
distributions. We do not observe any nonmonotonic behavior in the ratios of the
cumulants as a function of collision energy. The measured values of and can be directly compared to lattice
quantum-chromodynamics calculations and thus allow extraction of both the
chemical freeze-out temperature and the baryon chemical potential at each
center-of-mass energy.Comment: 512 authors, 8 pages, 4 figures, 1 table. v2 is version accepted for
publication in Phys. Rev. C as a Rapid Communication. Plain text data tables
for the points plotted in figures for this and previous PHENIX publications
are (or will be) publicly available at http://www.phenix.bnl.gov/papers.htm
Inclusive cross section and double-helicity asymmetry for production at midrapidity in collisions at GeV
PHENIX measurements are presented for the cross section and double-helicity
asymmetry () in inclusive production at midrapidity from
collisions at ~GeV from data taken in 2012 and 2013 at
the Relativistic Heavy Ion Collider. The next-to-leading-order
perturbative-quantum-chromodynamics theory calculation is in excellent
agreement with the presented cross section results. The calculation utilized
parton-to-pion fragmentation functions from the recent DSS14 global analysis,
which prefer a smaller gluon-to-pion fragmentation function. The
results follow an increasingly positive asymmetry trend with
and with respect to the predictions and are in excellent
agreement with the latest global analysis results. This analysis incorporated
earlier results on and jet , and suggested a positive
contribution of gluon polarization to the spin of the proton for the
gluon momentum fraction range . The data presented here extend to a
currently unexplored region, down to , and thus provide additional
constraints on the value of . The results confirm the evidence for
nonzero using a different production channel in a complementary
kinematic region.Comment: 413 authors, 8 pages, 4 figures. v2 is version accepted as PRD Rapid
Communication. Plain text data tables for the points plotted in figures for
this and previous PHENIX publications are (or will be) publicly available at
http://www.phenix.bnl.gov/papers.htm
L\'evy-stable two-pion Bose-Einstein correlations in GeV AuAu collisions
We present a detailed measurement of charged two-pion correlation functions
in 0%-30% centrality GeV AuAu collisions by the
PHENIX experiment at the Relativistic Heavy Ion Collider. The data are well
described by Bose-Einstein correlation functions stemming from L\'evy-stable
source distributions. Using a fine transverse momentum binning, we extract the
correlation strength parameter , the L\'evy index of stability
and the L\'evy length scale parameter as a function of average
transverse mass of the pair . We find that the positively and the
negatively charged pion pairs yield consistent results, and their correlation
functions are represented, within uncertainties, by the same L\'evy-stable
source functions. The measurements indicate a decrease of the
strength of the correlations at low . The L\'evy length scale parameter
decreases with increasing , following a hydrodynamically
predicted type of scaling behavior. The values of the L\'evy index of stability
are found to be significantly lower than the Gaussian case of
, but also significantly larger than the conjectured value that may
characterize the critical point of a second-order quark-hadron phase
transition.Comment: 448 authors, 25 pages, 11 figures, 4 tables, 2010 data. v2 is version
accepted for publication in Phys. Rev. C. Plain text data tables for the
points plotted in figures for this and previous PHENIX publications are (or
will be) publicly available at http://www.phenix.bnl.gov/papers.htm
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