3,792 research outputs found
From the ISR to RHIC--measurements of hard-scattering and jets using inclusive single particle production and 2-particle correlations
Hard scattering in p-p collisions, discovered at the CERN ISR in 1972 by the
method of leading particles, proved that the partons of Deeply Inelastic
Scattering strongly interacted with each other. Further ISR measurements
utilizing inclusive single or pairs of hadrons established that high pT
particles are produced from states with two roughly back-to-back jets which are
the result of scattering of constituents of the nucleons as desribed by Quantum
Chromodynamics (QCD), which was developed during the course of these
measurements. These techniques, which are the only practical method to study
hard-scattering and jet phenomena in Au+Au central collisions at RHIC energies,
are reviewed, as an introduction to present RHIC measurements.Comment: To appear in the proceedings of the workshop on Correlations and
Fluctuations in Relativistic Nuclear Collisions, MIT, Cambridge, MA, April
21-23, 2005, 10 pages, 9 figures, Journal of Physics: Conference Proceeding
Results from RHIC with Implications for LHC
Results from the PHENIX experiment at RHIC in p-p and Au+Au collisions are
reviewed from the perspective of measurements in p-p collisions at the CERN-ISR
which serve as a basis for many of the techniques used. Issues such as J/Psi
suppression and hydrodynamical flow in A+A collisions require data from
LHC-Ions for an improved understanding. Suppression of high pT particles in
Au+Au collisions, first observed at RHIC, also has unresolved mysteries such as
the equality of the suppression of inclusive pi0 (from light quarks and gluons)
and direct-single electrons (from the decay of heavy quarks) in the transverse
momentum range 4< pT < 9 GeV/c. This disfavors a radiative explanation of
suppression and leads to a fundamental question of whether the Higgs boson
gives mass to fermions. Observation of an exponential distribution of direct
photons in central Au+Au collisions for 1< pT <2 GeV/c where hard-processes are
negligible and with no similar exponential distribution in p-p collisions
indicates thermal photon emission from the medium at RHIC, making PHENIX at the
moment ``the hottest experiment in Physics''.Comment: Invited lectures at the International School of Subnuclear Physics,
47th Course, "The most unexpected at LHC and the status of High Energy
Frontier'', Erice, Sicily, Italy, August 29-September 7. 2009. 32 pages, 22
figure
Why the xE distribution triggered by a leading particle does not measure the fragmentation function but does measure the ratio of the transverse momenta of the away-side jet to the trigger-side jet
Hard-scattering of point-like constituents (or partons) in p-p collisions was
discovered at the CERN-ISR in 1972 by measurements utilizing inclusive single
or pairs of hadrons with large transverse momentum (). It was generally
assumed, following Feynman, Field and Fox, as shown by data from the CERN-ISR
experiments, that the distribution of away side hadrons from a single
particle trigger [with ], corrected for of fragmentation would
be the same as that from a jet-trigger and follow the same fragmentation
function as observed in or DIS. PHENIX attempted to measure the
fragmentation function from the away side
distribution of charged particles triggered by a in p-p collisions at
RHIC and showed by explicit calculation that the distribution is actually
quite insensitive to the fragmentation function. Illustrations of the original
arguments and ISR results will be presented. Then the lack of sensitivity to
the fragmentation function will be explained, and an analytic formula for the
distribution given, in terms of incomplete Gamma functions, for the case
where the fragmentation function is exponential. The away-side distribution in
this formulation has the nice property that it both exhibits scaling and
is directly sensitive to the ratio of the away jet to that of
the trigger jet, , and thus can be used, for example, to measure
the relative energy loss of the two jets from a hard-scattering which escape
from the medium in A+A collisions. Comparisons of the analytical formula to
RHIC measurements will be presented, including data from STAR and PHENIX,
leading to some interesting conclusions.Comment: 6 pages, 5 figures, Proceedings of Poster Session, 19th International
Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter
2006), November 14-20, 2006, Shanghai, P. R. Chin
Effectiveness of continence promotion for older women via community organisations: A cluster randomised trial
This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/3.0/Objectives: The primary objective of this cluster randomised controlled trial was to compare the effectiveness of the three experimental continence promotion interventions against a control intervention on urinary symptom improvement in older women with untreated incontinence recruited from community organisations. A second objective was to determine whether changes in incontinence-related knowledge and new uptake of risk-modifying behaviours explain these improvements.
Setting: 71 community organisations across the UK.
Participants: 259 women aged 60 years and older with untreated incontinence entered the trial; 88% completed the 3-month follow-up.
Interventions: The three active interventions consisted of a single 60 min group workshop on (1) continence education (20 clusters, 64 women); (2) evidence-based self-management (17 clusters, 70 women); or (3) combined continence education and self-management (17 clusters, 61 women). The control intervention was a single 60 min educational group workshop on memory loss, polypharmacy and osteoporosis (17 clusters, 64 women).
Primary and secondary outcome measures: The primary outcome was self-reported improvement in incontinence 3 months postintervention at the level of the individual. The secondary outcome was change in the International Consultation on Incontinence Questionnaire (ICIQ) from baseline to 3-month follow-up. Changes in incontinence-related knowledge and behaviours were also assessed.
Results: The highest rate of urinary symptom improvement occurred in the combined intervention group (66% vs 11% of the control group, prevalence difference 55%, 95% CI 43% to 67%, intracluster correlation 0). 30% versus 6% of participants reported significant improvement respectively (prevalence difference 23%, 95% CI 10% to 36%, intracluster correlation 0). The number-needed-to-treat was 2 to achieve any improvement in incontinence symptoms, and 5 to attain significant improvement. Compared to controls, participants in the combined intervention reported an adjusted mean 2.05 point (95% CI 0.87 to 3.24) greater improvement on the ICIQ from baseline to 3-month follow-up. Changes in knowledge and self-reported risk-reduction behaviours paralleled rates of improvement in all intervention arms.
Conclusions: Continence education combined with evidence-based self-management improves symptoms of incontinence among untreated older women. Community organisations represent an untapped vector for delivering effective continence promotion interventions.Canadian Institutes of Health Research – Institute on
Aging and the Economic and Social Research Council (UK
A fundamental test of the Higgs Yukawa coupling at RHIC in A+A collisions
Searches for the intermediate boson, , the heavy quantum of the Weak
Interaction, via its semi-leptonic decay, , in the 1970's instead
discovered unexpectedly large hadron production at high , notably ,
which provided a huge background of from internal and external
conversions. Methods developed at the CERN ISR which led to the discovery of
direct-single- in 1974, later determined to be from the semi-leptonic
decay of charm which had not yet been discovered, were used by PHENIX at RHIC
to make precision measurements of heavy quark production in p-p and Au+Au
collisions, leading to the puzzle of apparent equal suppression of light and
heavy quarks in the QGP. If the Higgs mechanism gives mass to gauge bosons but
not to fermions, then a proposal that all 6 quarks are nearly massless in a
QGP, which would resolve the puzzle, can not be excluded. This proposal can be
tested with future measurements of heavy quark correlations in A+A collisionsComment: 12 pages, 16 figures, 26th Winter Workshop on Nuclear Dynamics, Ocho
Rios, Jamaica WI, January 2-9, 2010. Corrected citation of 1974 direct single
lepton discover
Mucocutaneous disease and related clinical characteristics in hospitalized children and adolescents with COVID-19 and multisystem inflammatory syndrome in children.
Background
Little is known about mucocutaneous disease in acutely ill children and adolescents with COVID-19 and multisystem inflammatory syndrome in children (MIS-C). Objective
To characterize mucocutaneous disease and its relation to clinical course among hospitalized patients with COVID-19 and MIS-C. Methods
Descriptive cohort study of prospectively and consecutively hospitalized eligible patients between May 11, 2020 and June 5, 2020. Results
In COVID-19 patients, 4 of 12 (33%) had rash and/or mucositis, including erythema, morbilliform pattern, and lip mucositis. In MIS-C patients, 9 of 19 (47%) had rash and/or mucositis, including erythema, morbilliform, retiform purpura, targetoid and urticarial patterns, along with acral edema, lip mucositis, tongue papillitis, and conjunctivitis. COVID-19 patients with rash had less frequent respiratory symptoms, pediatric intensive care unit admission, invasive ventilation, and shorter stay versus COVID-19 patients without rash. MIS-C patients with rash had less frequent pediatric intensive care unit admission, shock, ventilation, as well as lower levels of C-reactive protein, ferritin, D-dimer, and troponin (vs MIS-C without rash). Neutrophil-to-lymphocyte ratio was similar for patients with and without rash in both groups. None of the MIS-C patients met criteria for Kawasaki disease. Limitations
Small sample sizes. Conclusions
Mucocutaneous disease is common among children and adolescents with COVID-19 and MIS-C. Laboratory trends observed in patients with rash may prognosticate a less severe course
A compilation, classification, and comparison of lists of spontaneous speaking vocabulary of children in kindergarten, Grade I, Grade II, and Grade III
Thesis (Ed.M.)--Boston UniversityLanguage development has been studied for many years.
The beginning vocabularies are easy to count ana record.
As tne child grows and moves about, his speaking vocabulary
increases very rapidly. Some estimates suggest
that a minimum speaking vocabulary at six years would include
three thousand words.
New words have come into children's speaking vocabularies
as a result of modern technology since World War II.
Lists of spontaneous vocabulary furnish material for teachers
and text book writers. The purpose of this study is
to analyze two lists recorded in 1954 and 1955.
An attempt has been made to classify the new list.
The lists were compared with three existing lists, Rinsland,
International Kindergarten Union and Gates
Transverse momentum fluctuations and percolation of strings
The behaviour of the transverse momentum fluctuations with the centrality of
the collision shown by the Relativistic Heavy Ion Collider data is naturally
explained by the clustering of color sources. In this framework, elementary
color sources --strings-- overlap forming clusters, so the number of effective
sources is modified. These clusters decay into particles with mean transverse
momentum that depends on the number of elementary sources that conform each
cluster, and the area occupied by the cluster. The transverse momentum
fluctuations in this approach correspond to the fluctuations of the transverse
momentum of these clusters, and they behave essentially as the number of
effective sources.Comment: 16 pages, RevTex, 4 postscript figures. Enhanced version. New figure
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