1,776 research outputs found
A Catalog of the Highest-energy Cosmic Rays Recorded during Phase I of Operation of the Pierre Auger Observatory
A catalog containing details of the highest-energy cosmic rays recorded through the detection of extensive air showers at the Pierre Auger Observatory is presented with the aim of opening the data to detailed examination. Descriptions of the 100 showers created by the highest-energy particles recorded between 2004 January 1 and 2020 December 31 are given for cosmic rays that have energies in the range 78–166 EeV. Details are also given on a further nine very energetic events that have been used in the calibration procedure adopted to determine the energy of each primary. A sky plot of the arrival directions of the most energetic particles is shown. No interpretations of the data are offered.Fil: Binet, V. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Física de Rosario (IFIR-CONICET); Argentina.Fil: Micheletti, M. I. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Física de Rosario (IFIR-CONICET); Argentina
La Fatigue Intellectuelle
Mode of access: Internet
Prevalence and determinants of chronic kidney disease in the Swiss population.
QUESTIONS UNDER STUDY: The prevalence of chronic kidney disease (CKD) is increasing worldwide, corresponding to an increased risk of cardiovascular disease. The latest study on prevalence of CKD involving the three linguistic regions of Switzerland dates back to 2002-2003 and definitions have changed since then. We aimed to assess the current prevalence and determinants of CKD in the Swiss general population.
METHODS: We analysed the data of 1353 participants from a cross-sectional population-based survey performed in 2010-2012 in the three linguistic regions of Switzerland. The prevalence of CKD and the derived cardiovascular risk categories were assessed according to the Kidney Disease - Improving Global Outcomes (KDIGO) 2012 classification, using estimated glomerular filtration rate (GFR; CKD-Epidemiological Collaboration equation) and albuminuria level. Multivariate logistic regression was used to analyse factors associated with CKD.
RESULTS: We included 660 men and 693 women, equally distributed in four age categories (15-29, 30-44, 45-59 and over 60 years). The overall prevalence of CKD was 10.4%. The prevalence in the low, moderate, high and very high risk KDIGO categories were 89.6%, 8.4%, 1.6% and 0.5%, respectively. The prevalence of CKD was similar in all linguistic regions. In multivariate analysis, female gender, older age, diabetes and uric acid were independently associated with CKD in persons ≥45 y. In younger participants, diabetes and lower educational level were associated with CKD.
CONCLUSIONS: In the general Swiss population, CKD affects one in ten adults. Subjects older than 60 years, as well as patients with diabetes and hypertension, show a high prevalence of CKD. Systematic screening may be recommended in this population
Associations of sodium, potassium and protein intake with blood pressure and hypertension in Switzerland.
Nutritional factors play an important role in the regulation of blood pressure and in the development of hypertension. In this analysis, we explored the associations of 24-hour urinary Na+, K+ and urea excretion with blood pressure levels and the risk of hypertension in the Swiss population, taking regional linguistic differences into account.
The Swiss Survey on Salt is a population based cross-sectional study that included 1336 subjects from the three main linguistic regions (French, German and Italian) of Switzerland. Blood pressure was measured with a validated oscillometric Omron HEM 907 device. Hypertension was defined as current antihypertensive treatment or a mean systolic blood pressure >140 mm Hg and/or diastolic >90 mm Hg, based on eight blood pressure measurements performed at two visits. Na+, K+ and urea excretion were assessed in 24-hour urine collections. We use multiple logistic/linear regressions to explore the associations of urine Na+, K+ and urea with blood pressure / hypertension, taking into account potential confounders and effect modifiers.
The prevalence of hypertension was 30%, 26% and 17% in the German-, French- and Italian- speaking regions respectively, (p-value across regions <0.001). In the Swiss adult population, besides age, sex, and body mass index, urinary Na+ excretion was positively associated with systolic blood pressure and hypertension. Urinary K+ excretion tended to be negatively associated with blood pressure but this was not significant (p = 0.08). Hypertensive people had a higher 24-hour urinary Na+/K+ ratio than normotensive people (p = 0.003). Urinary urea excretion was associated with neither blood pressure nor hypertension. Participants from the German-speaking region had a higher likelihood of having a high systolic blood pressure.
We confirm a high prevalence of elevated blood pressure in Swiss adults, including regional differences. In Switzerland, urinary Na+ excretion is associated positively with blood pressure and hypertension, independently of urinary K+ and urea excretion. The observed differences in blood pressure levels across linguistic regions are independent of the urinary Na+, K+ and urea excretion
Precision Measurement of the Neutron Spin Asymmetries and Spin-dependent Structure Functions in the Valence Quark Region
We report on measurements of the neutron spin asymmetries and
polarized structure functions at three kinematics in the deep
inelastic region, with , 0.47 and 0.60 and , 3.5 and 4.8
(GeV/c), respectively. These measurements were performed using a 5.7 GeV
longitudinally-polarized electron beam and a polarized He target. The
results for and at are consistent with previous world
data and, at the two higher points, have improved the precision of the
world data by about an order of magnitude. The new data show a zero
crossing around and the value at is significantly positive.
These results agree with a next-to-leading order QCD analysis of previous world
data. The trend of data at high agrees with constituent quark model
predictions but disagrees with that from leading-order perturbative QCD (pQCD)
assuming hadron helicity conservation. Results for and have a
precision comparable to the best world data in this kinematic region. Combined
with previous world data, the moment was evaluated and the new result
has improved the precision of this quantity by about a factor of two. When
combined with the world proton data, polarized quark distribution functions
were extracted from the new values based on the quark parton
model. While results for agree well with predictions from various
models, results for disagree with the leading-order pQCD
prediction when hadron helicity conservation is imposed.Comment: A typing error in A_\parallel(3He) at x=0.47 in Table VII of Phys.
Rev. C has been noticed and correcte
Precision Measurement of the Neutron Spin Asymmetry and Spin-Flavor Decomposition in the Valence Quark Region
We have measured the neutron spin asymmetry with high precision at
three kinematics in the deep inelastic region at , 0.47 and 0.60, and
, 3.5 and 4.8 (GeV/c), respectively. Our results unambiguously
show, for the first time, that crosses zero around and becomes
significantly positive at . Combined with the world proton data,
polarized quark distributions were extracted. Our results, in general, agree
with relativistic constituent quark models and with perturbative quantum
chromodynamics (pQCD) analyses based on the earlier data. However they deviate
from pQCD predictions based on hadron helicity conservation.Comment: 5 pages, 2 figures, this is the final version appeared in Phys. Rev.
Let
Has education lost sight of children?
The reflections presented in this chapter are informed by clinical and personal experiences of school education in the UK. There are many challenges for children and young people in the modern education system and for the professionals who support them. In the UK, there are significant gaps between the highly selective education provided to those who pay privately for it and to the majority of those educated in the state-funded system. Though literacy rates have improved around the world, many children, particularly boys, do not finish their education for reasons such as boredom, behavioural difficulties or because education does not ‘pay’. Violence, bullying, and sexual harassment are issues faced by many children in schools and there are disturbing trends of excluding children who present with behavioural problems at school whose origins are not explored. Excluded children are then educated with other children who may also have multiple problems which often just make the situation worse. The experience of clinicians suggests that school-related mental health problems are increasing in severity. Are mental health services dealing with the consequences of an education system that is not meeting children’s needs? An education system that is testing- and performance-based may not be serving many children well if it is driving important decisions about them at increasingly younger ages. Labelling of children and setting them on educational career paths can occur well before they reach secondary schools, limiting potential very early on in their developmental trajectory. Furthermore, the emphasis at school on testing may come at the expense of creativity and other forms of intelligence, which are also valuable and important. Meanwhile the employment marketplace requires people with widely different skills, with an emphasis on innovation, creativity, and problem solving. Is education losing sight of the children it is educating
Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC
The uncertainty on the calorimeter energy response to jets of particles is
derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the
calorimeter response to single isolated charged hadrons is measured and
compared to the Monte Carlo simulation using proton-proton collisions at
centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009
and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter
response to specific types of particles (positively and negatively charged
pions, protons, and anti-protons) is measured and compared to the Monte Carlo
predictions. Finally, the jet energy scale uncertainty is determined by
propagating the response uncertainty for single charged and neutral particles
to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3%
for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table,
submitted to European Physical Journal
Harmonic Sums and Mellin Transforms up to two-loop Order
A systematic study is performed on the finite harmonic sums up to level four.
These sums form the general basis for the Mellin transforms of all individual
functions of the momentum fraction emerging in the quantities of
massless QED and QCD up to two--loop order, as the unpolarized and polarized
splitting functions, coefficient functions, and hard scattering cross sections
for space and time-like momentum transfer. The finite harmonic sums are
calculated explicitly in the linear representation. Algebraic relations
connecting these sums are derived to obtain representations based on a reduced
set of basic functions. The Mellin transforms of all the corresponding Nielsen
functions are calculated.Comment: 44 pages Latex, contract number adde
Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC
Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson
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