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Central exclusive chi (c) meson production at the Tevatron revisited
Motivated by the recent experimental observation of exclusive c events at
the Tevatron, we revisit earlier studies of central exclusive scalar c0 meson production,
before generalising the existing formalism to include c1 and c2 mesons. Although c0
production was previously assumed to be dominant, we find that the c1 and c2 rates for
the experimentally considered c ! J/
! μ+μ−
decay process are in fact comparable
to the c0 rate. We have developed a new Monte Carlo event generator, SuperCHIC,
which models the central exclusive production of the three c states via this decay chain,
and have explored possible ways of distinguishing them, given that their mass differences
are not resolvable within the current experimental set-up. Although we find that the
severity of current experimental cuts appears to preclude this, the acceptance does not
change crucially between the three states and so our conclusions regarding the overall rates
remain unchanged. This therefore raises the interesting possibility that exclusive c1 and
c2 production has already been observed at the Tevatron
Hungry for change: the Sydney Food Fairness Alliance
The Sydney Food Fairness Alliance is one of a growing number of nascent food movements in Australia to have emerged out of concern for the country’s food future, as well as the deleterious effect the present food system is having on its citizens’ health and the continent’s fragile environment. The Alliance’s structure and activities clearly position it as a new social movement (NSM) engaged in collective action on a specific issue, in this instance, food security/justice, and operating outside the political sphere while aiming to influence and affect societal change. Food security as a human right lies at the heart of the Alliance’s philosophy, and equitable, sustainable food policies for New South Wales are a core focus of its advocacy work. The authors argue that the Alliance is a distinctive food movement in that it positions itself as an \u27umbrella\u27 organization representing a wide range of stakeholders in the food system. This chapter reflects on the values, achievements, issues of concern, strengths and weaknesses, and future of the Sydney Food Fairness Alliance.
This resource is Chapter 8 in \u27Food Security in Australia: Challenges and Prospects for the Future\u27 published by Springer in 2013
Sensory Electrical Stimulation Improves Foot Placement during Targeted Stepping Post-Stroke
Proper foot placement is vital for maintaining balance during walking, requiring the integration of multiple sensory signals with motor commands. Disruption of brain structures post-stroke likely alters the processing of sensory information by motor centers, interfering with precision control of foot placement and walking function for stroke survivors. In this study, we examined whether somatosensory stimulation, which improves functional movements of the paretic hand, could be used to improve foot placement of the paretic limb. Foot placement was evaluated before, during, and after application of somatosensory electrical stimulation to the paretic foot during a targeted stepping task. Starting from standing, twelve chronic stroke participants initiated movement with the non-paretic limb and stepped to one of five target locations projected onto the floor with distances normalized to the paretic stride length. Targeting error and lower extremity kinematics were used to assess changes in foot placement and limb control due to somatosensory stimulation. Significant reductions in placement error in the medial–lateral direction (p = 0.008) were observed during the stimulation and post-stimulation blocks. Seven participants, presenting with a hip circumduction walking pattern, had reductions (p = 0.008) in the magnitude and duration of hip abduction during swing with somatosensory stimulation. Reductions in circumduction correlated with both functional and clinical measures, with larger improvements observed in participants with greater impairment. The results of this study suggest that somatosensory stimulation of the paretic foot applied during movement can improve the precision control of foot placement
Towards the glueball spectrum from unquenched lattice QCD
We use a variational technique to study heavy glueballs on gauge
configurations generated with 2+1 flavours of ASQTAD improved staggered
fermions. The variational technique includes glueball scattering states. The
measurements were made using 2150 configurations at 0.092 fm with a pion mass
of 360 MeV. We report masses for 10 glueball states. We discuss the prospects
for unquenched lattice QCD calculations of the oddballs.Comment: 19 pages, 4 tables and 8 figures. One figure added. Now matches the
published versio
Ultracold dense gas of deeply bound heteronuclear molecules
Recently, the quest for an ultracold and dense ensemble of polar molecules
has attracted strong interest. Polar molecules have bright prospects for novel
quantum gases with long-range and anisotropic interactions, for quantum
information science, and for precision measurements. However, high-density
clouds of ultracold polar molecules have so far not been produced. Here, we
report a key step towards this goal. Starting from an ultracold dense gas of
heteronuclear 40K-87Rb Feshbach molecules with typical binding energies of a
few hundred kHz and a negligible dipole moment, we coherently transfer these
molecules into a vibrational level of the ground-state molecular potential
bound by >10 GHz. We thereby increase the binding energy and the expected
dipole moment of the 40K-87Rb molecules by more than four orders of magnitude
in a single transfer step. Starting with a single initial state prepared with
Feshbach association, we achieve a transfer efficiency of 84%. While dipolar
effects are not yet observable, the presented technique can be extended to
access much more deeply bound vibrational levels and ultimately those
exhibiting a significant dipole moment. The preparation of an ultracold quantum
gas of polar molecules might therefore come within experimental reach.Comment: 5 pages, 5 figure
Stellar Coronal and Wind Models: Impact on Exoplanets
Surface magnetism is believed to be the main driver of coronal heating and
stellar wind acceleration. Coronae are believed to be formed by plasma confined
in closed magnetic coronal loops of the stars, with winds mainly originating in
open magnetic field line regions. In this Chapter, we review some basic
properties of stellar coronae and winds and present some existing models. In
the last part of this Chapter, we discuss the effects of coronal winds on
exoplanets.Comment: Chapter published in the "Handbook of Exoplanets", Editors in Chief:
Juan Antonio Belmonte and Hans Deeg, Section Editor: Nuccio Lanza. Springer
Reference Work
Searching for the odderon in ultraperipheral proton-ion collisions at the LHC
We explore the possibility of observing odderon exchange in proton-ion collisions at the LHC, via the ultraperipheral photoproduction of C-even mesons. As well as the signal, we consider in detail the principle backgrounds, due to QCD-initiated production (i.e., double pomeron exchange) and γγ fusion. We find that while the photon-initiated background is dominant at very small momentum transfer, this can be effectively removed by placing a reasonable cut on the transverse momentum of the produced meson. In the case of QCD-initiated production, we show this is in general strongly suppressed by the small probability of no additional particle production in the central detector, namely the survival factor. In some scenarios, this suppression is sufficient to permit the observation of odderon exchange in Pb-p collisions in a clean environment, or else to place bounds on this. We in addition identify the cases of π0 and η(548) production as particularly promising channels. Here, the QCD-initiated background is absent for π0 due to isospin conservation and very small for η(548) due to its dominantly flavor octet nature and odd parity
Nutritional management of chronic renal failure by dietitians - the South African experience
Objective: The objective of this descriptive study was to assess the practices of South African dietitians regarding the dietary treatment of patients with chronic renal failure.Subjects and design: A questionnaire was mailed to 600 randomly selected dietitians registered with the Health Professions Council of South Africa. Practices were compared to international standards for pre-dialysis, haemodialysis (HD) and peritoneal dialysis (PD) patients.Results: A 26% response rate was obtained, with only 28% of these dietitians indicating that they counsel renal patients. The majority of dietitians met the international dietary recommendations, but a substantial number deviated from them. This was especially evident in PD patients, where the deviation ranged from 20% (4 dietitians) in the case of energy and phosphate, to 55% (11 dietitians) in the case of calcium. Parameters used for the assessment of nutritional status included body mass index (45% of dietitians), serum albumin (44%), clinical examinations (43%), bioelectrical impedance (37%) and diet history (36%). Methods used to monitor dietary compliance included biochemistry, dietary history, anthropometric measurements and clinical investigation. The most frequently used approaches in the management of protein-energy malnutrition included supplemental drinks (86%) and dietary enrichment at household level (76%).Conclusion: Although the majority of dietitians met international standards for most nutrients, there was some variation and uncertainty. Ongoing education will enable South African dietitians to treat renal patients competently and with confidence.South African Journal of Clinical Nutrition Vol. 18(2) 2005: 60-6
Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector
Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos2Δϕ modulation for all ΣETPb ranges and particle pT
Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector
Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente
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