300 research outputs found
Acetylcholinesterase of human erythrocytes and neuromuscular junctions: homologies revealed by monoclonal antibodies.
THE ACCUSED IS ENTERING THE COURTROOM: THE LIVE-TWEETING OF A MURDER TRIAL.
© 2017 Informa UK Limited, trading as Taylor & Francis GroupThe use of social media is now widely accepted within journalism as an outlet for news information. Live tweeting of unfolding events is standard practice. In March 2014, Oscar Pistorius went on trial in the Gauteng High Court for murder. Hundreds of journalists present began live-tweeting coverage, an unprecedented combination of international interest, permission to use technology and access which resulted in massive streams of consciousness reports of events as they unfolded. Based on a corpus of Twitter feeds of twenty-four journalists covering the trial, this study analyses the content and strategies of these feeds in order to present an understanding of how microblogging is used as a live reporting tool. This study shows the development of standardised language and strategies in reporting on Twitter, concluding that journalists adopt a narrow range of approaches, with no significant variation in terms of gender, location, or medium. This is in contrast to earlier studies in the field (Awad, 2006, Hedman, 2015; Kothari, 2010; Lariscy, Avery, Sweetser, & Howes, 2009 Lasorsa, 2012; Lasorsa, Lewis, & Holton, 2011; Sigal, 1999, Vis, 2013).Peer reviewe
Electric dipole moments of Hg, Xe, Rn, Ra, Pu, and TlF induced by the nuclear Schiff moment and limits on time-reversal violating interactions
We have calculated the atomic electric dipole moments (EDMs) induced in
^{199}Hg, ^{129}Xe, ^{223}Rn, ^{225}Ra, and ^{239}Pu by their respective
nuclear Schiff moments S. The results are (in units 10^{-17}S(e {fm}^{3})^{-1}e
cm): d(^{199}Hg)=-2.8, d(^{129}Xe)=0.38, d(^{223}Rn)=3.3, d(^{225}Ra)=-8.5,
d(^{239}Pu)=-11. We have also calculated corrections to the parity- and
time-invariance-violating (P,T-odd) spin-axis interaction constant in TlF.
These results are important for the interpretation of atomic and molecular
experiments on EDMs in terms of fundamental P,T-odd parameters.Comment: 16 page
Nucleon Edm from Atomic Systems and Constraints on Supersymmetry Parameters
The nucleon EDM is shown to be directly related to the EDM of atomic systems.
From the observed EDM values of the atomic Hg system, the neutron EDM can be
extracted, which gives a very stringent constraint on the supersymmetry
parameters. It is also shown that the measurement of Nitrogen and Thallium
atomic systems should provide important information on the flavor dependence of
the quark EDM. We perform numerical analyses on the EDM of neutron, proton and
electron in the minimal supersymmetric standard model with CP-violating phases.
We demonstrate that the new limit on the neutron EDM extracted from atomic
systems excludes a wide parameter region of supersymmetry breaking masses above
1 TeV, while the old limit excludes only a small mass region below 1 TeV.Comment: 10 pages, 7 figure file
Using Heat to Characterize Streambed Water Flux Variability in Four Stream Reaches
Estimates of streambed water fl ux are needed for the interpretation of streambed chemistry and reactions. Continuous temperature and head monitoring in stream reaches within four agricultural watersheds (Leary Weber Ditch, IN; Maple Creek, NE; DR2 Drain, WA; and Merced River, CA) allowed heat to be used as a tracer to study the temporal and spatial variability of fluxes through the streambed. Synoptic methods (seepage meter and differential discharge measurements) were compared with estimates obtained by using heat as a tracer. Water flux was estimated by modeling one-dimensional vertical flow of water and heat using the model VS2DH. Flux was influenced by physical heterogeneity of the stream channel and temporal variability in stream and ground-water levels. During most of the study period (April–December 2004), flux was upward through the streambeds. At the IN, NE, and CA sites, high-stage events resulted in rapid reversal of flow direction inducing short-term surface-water flow into the streambed. During late summer at the IN site, regional ground-water levels dropped, leading to surface-water loss to ground water that resulted in drying of the ditch. Synoptic measurements of flux generally supported the model flux estimates. Water flow through the streambed was roughly an order of magnitude larger in the humid basins (IN and NE) than in the arid basins (WA and CA). Downward flux, in response to sudden high streamflows, and seasonal variability in flux was most pronounced in the humid basins and in high conductivity zones in the streambed
Hadronic EDMs, the Weinberg Operator, and Light Gluinos
We re-examine questions concerning the contribution of the three-gluon
Weinberg operator to the electric dipole moment of the neutron, and provide
several QCD sum rule-based arguments that the result is smaller than - but
nevertheless consistent with - estimates which invoke naive dimensional
analysis. We also point out a regime of the MSSM parameter space with light
gluinos for which this operator provides the dominant contribution to the
neutron electric dipole moment due to enhancement via the dimension five color
electric dipole moment of the gluino.Comment: 6 pages, RevTeX, 3 figures; v2: references added; v3: typos
corrected, to appear in Phys. Rev.
Hydrogeochemical controls on brook trout spawning habitats in a coastal stream
Brook trout (Salvelinus fontinalis) spawn in fall and
overwintering egg development can benefit from stable, relatively warm
temperatures in groundwater-seepage zones. However, eggs are also sensitive
to dissolved oxygen concentration, which may be reduced in discharging
groundwater (i.e., seepage). We investigated a 2 km reach of the coastal
Quashnet River in Cape Cod, Massachusetts, USA, to relate preferred fish
spawning habitats to geology, geomorphology, and discharging groundwater
geochemistry. Thermal reconnaissance methods were used to locate zones of
rapid groundwater discharge, which were predominantly found along the central
channel of a wider stream valley section. Pore-water chemistry and temporal
vertical groundwater flux were measured at a subset of these zones during
field campaigns over several seasons. Seepage zones in open-valley
sub-reaches generally showed suboxic conditions and higher dissolved solutes
compared to the underlying glacial outwash aquifer. These discharge zones
were cross-referenced with preferred brook trout redds and evaluated during
10 years of observation, all of which were associated with discrete alcove
features in steep cutbanks, where stream meander bends intersect the glacial
valley walls. Seepage in these repeat spawning zones was generally stronger
and more variable than in open-valley sites, with higher dissolved oxygen and
reduced solute concentrations. The combined evidence indicates that regional
groundwater discharge along the broader valley bottom is predominantly
suboxic due to the influence of near-stream organic deposits; trout show no
obvious preference for these zones when spawning. However, the meander bends
that cut into sandy deposits near the valley walls generate strong oxic
seepage zones that are utilized routinely for redd construction and the
overwintering of trout eggs. Stable water isotopic data support the
conclusion that repeat spawning zones are located directly on preferential
discharges of more localized groundwater. In similar coastal systems with
extensive valley peat deposits, the specific use of groundwater-discharge points
by brook trout may be limited to morphologies such as cutbanks, where
groundwater flow paths do not encounter substantial buried organic material
and remain oxygen-rich.</p
Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
The current status of electric dipole moments of diamagnetic atoms which
involves the synergy between atomic experiments and three different theoretical
areas -- particle, nuclear and atomic is reviewed. Various models of particle
physics that predict CP violation, which is necessary for the existence of such
electric dipole moments, are presented. These include the standard model of
particle physics and various extensions of it. Effective hadron level combined
charge conjugation (C) and parity (P) symmetry violating interactions are
derived taking into consideration different ways in which a nucleon interacts
with other nucleons as well as with electrons. Nuclear structure calculations
of the CP-odd nuclear Schiff moment are discussed using the shell model and
other theoretical approaches. Results of the calculations of atomic electric
dipole moments due to the interaction of the nuclear Schiff moment with the
electrons and the P and time-reversal (T) symmetry violating
tensor-pseudotensor electron-nucleus are elucidated using different
relativistic many-body theories. The principles of the measurement of the
electric dipole moments of diamagnetic atoms are outlined. Upper limits for the
nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained
combining the results of atomic experiments and relativistic many-body
theories. The coefficients for the different sources of CP violation have been
estimated at the elementary particle level for all the diamagnetic atoms of
current experimental interest and their implications for physics beyond the
standard model is discussed. Possible improvements of the current results of
the measurements as well as quantum chromodynamics, nuclear and atomic
calculations are suggested.Comment: 46 pages, 19 tables and 16 figures. A review article accepted for
EPJ
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