167,618 research outputs found
Towards a controlled study of the QCD critical point
The phase diagram of QCD, as a function of temperature T and quark chemical
potential mu, may contain a critical point (mu_E,T_E) whose non-perturbative
nature makes it a natural object of lattice studies. However, the sign problem
prevents the application of standard Monte Carlo techniques at non-zero baryon
density. We have been pursuing an approach free of the sign problem, where the
chemical potential is taken as imaginary and the results are Taylor-expanded in
mu/T about mu=0, then analytically continued to real mu.
Within this approach we have determined the sensitivity of the critical
chemical potential mu_E to the quark mass, d(\mu_E)^2/dm_q|_{\mu_E=0}. Our
study indicates that the critical point moves to {\em smaller} chemical
potential as the quark mass {\em increases}. This finding, contrary to common
wisdom, implies that the deconfinement crossover, which takes place in QCD at
mu=0 when the temperature is raised, will remain a crossover in the mu-region
where our Taylor expansion can be trusted. If this result, obtained on a coarse
lattice, is confirmed by simulations on finer lattices now in progress, then we
predict that no {\em chiral} critical point will be found for mu_B \lesssim 500
MeV, unless the phase diagram contains additional transitions.Comment: 4 pages, 6 figures, proceedings of Quark Matter 2008, Jaipur (India),
Feb. 2008, to appear in J. Phys.
A Controlled Study on the Characterisation of Bioaerosols Emissions from Compost
Bioaerosol emissions arising from biowaste treatment are an issue of public concern. To better characterise the bioaerosols, and to assess a range of measurement methods, we aerosolised green waste compost under controlled conditions. Viable and non-viable Andersen samplers, cyclone samplers and a real time bioaerosol detection system (Spectral Intensity Bioaerosol Sensor (SIBS)) were deployed simultaneously. The number-weighted fraction of fluorescent particles was in the range 22–26% of all particles for low and high emission scenarios. Overall fluorescence spectral profiles seen by the SIBS exhibited several peaks across the 16 wavelength bands from 298 to 735 nm. The size-fractionated endotoxin profile showed most endotoxin resided in the 2.1–9 μm aerodynamic diameter fraction, though up to 27% was found in a finer size fraction. A range of microorganisms were detected through culture, Matrix Assisted Laser Desorption and Ionisation Time of Flight Mass Spectrometry (MALDI-TOF) and quantitative polymerase chain reaction (qPCR), including Legionella pneumophila serogroup 1. These findings contribute to our knowledge of the physico-chemical and biological characteristics of bioaerosols from composting sites, as well as informing future monitoring approaches and data interpretation for bioaerosol measurement
Sexual harassment and eating disorders in female elite athletes - A controlled study
The aims were to examine the percentage of female elite athletes and controls reporting sexual harassment and abuse (SHAB), and whether a higher percentage of female athletes with eating disorders (ED) had experienced SHAB. A questionnaire was administered to the total population of female elite athletes (n=660) and controls (n=780) aged 15-39 years. SHAB were measured through 11 questions, ranging from light to severe SHAB. In addition, questions about dietary-, menstrual- and training history and the Eating Disorder Inventory were included. The response rate was 88% for athletes and 71% for controls. Athletes (n=121) and controls (n=81) classified as “at risk” for ED and non-ED controls participated in a clinical interview. A higher percentage of controls, compared with athletes reported experiences of SHAB in general (59% vs. 51%, p<0.001). A lower percentage of athletes had experienced SHAB in sports than outside sport (28% vs.39%, p<0.001). A higher percentage of ED athletes than non-ED athletes had experienced SHAB (66% vs.48%) (p<0.01), both inside sport and outside sport. In spite of the fact that a higher percentage of controls compared with athletes had experienced SHAB, it is necessary to formulate clear guidelines, set up educational workshops and implement intervention programs for both ED and SHAB in sport
A controlled study of community-based exercise training in patients with moderate COPD.
BackgroundThe effectiveness of clinic-based pulmonary rehabilitation in advanced COPD is well established, but few data exist for less severe patients treated in alternative settings. The purpose of this study was to investigate whether a novel, community-based exercise program (CBE) was feasible and effective for patients with moderate COPD.MethodsNineteen patients with moderate COPD (mean FEV1 62%) and self-reported exercise impairment were randomized to 12-weeks of progressive endurance and strength training at a local health club under the guidance of a certified personal trainer, or to continuation of unsupervised habitual physical activity. Outcomes assessed at baseline and 12 weeks included session compliance, intensity adherence, treadmill endurance time, muscle strength, dyspnea, and health status.ResultsCompliance was 94% and adherence was 83%. Comparisons between CBE and control groups yielded the following mean (SEM) differences in favor of CBE: endurance time 134 (74) seconds versus -59 (49) seconds (P=0.041) and TDI 5.1 (0.8) versus -0.2 (0.5) (P<0.001). The CBE group increased muscle strength (weight lifted) by 11.8 kilograms per subject per week of training (P<0.001). SGRQ was not significantly changed.ConclusionsWe demonstrated the feasibility and effectiveness of a novel community-based exercise program involving health clubs and personal trainers for patients with moderate COPD.Trial registrationClinicalTrials.gov Identifier NCT01985529
A controlled study of cold dust content in galaxies from
At , the formation of new stars is dominated by dusty galaxies whose
far-IR emission indicates they contain colder dust than local galaxies of a
similar luminosity. We explore the reasons for the evolving IR emission of
similar galaxies over cosmic time using: 1) Local galaxies from GOALS ; 2) Galaxies at from the 5MUSES
(); 3) IR luminous galaxies spanning
from GOODS and Spitzer xFLS (). All
samples have Spitzer mid-IR spectra, and Herschel and ground-based
submillimeter imaging covering the full IR spectral energy distribution,
allowing us to robustly measure ,
, and for every galaxy. Despite similar infrared
luminosities, dusty star forming galaxies have a factor of 5 higher
dust masses and 5K colder temperatures. The increase in dust mass is linked
with an increase in the gas fractions with redshift, and we do not observe a
similar increase in stellar mass or star formation efficiency.
, a proxy
for , is strongly correlated with independently of redshift. We
measure merger classification and galaxy size for a subsample, and there is no
obvious correlation between these parameters and or . In dusty star forming galaxies, the
change in can fully
account for the observed colder dust temperatures, suggesting that any change
in the spatial extent of the interstellar medium is a second order effect.Comment: Accepted for publication in ApJ. 21 pages, 11 figure
Medication overuse headache, addiction and personality pathology: a controlled study by SWAP-200
Background: Medication Overuse Headache (MOH) is a type of chronic headache, whose mechanisms are still unknown. Some empirical investigations examining the addiction-like behaviors and processes, as well as personality characteristics underlying MOH development, reached contrasting findings. This study aimed at detecting personality and its disorders (PDs) in MOH patients, with a specific attention to the features of addiction. Methods: Eighty-eight MOH patients have been compared with two clinical populations including 99 patients with Substance Use Disorder (SUD) and 91 with PDs using the Shedler-Westen Assessment Procedure-200 (SWAP-200). MANCOVAs were performed to evaluate personality differences among MOH, SUD and PD groups, controlling for age and gender. Results: MOH patients showed lower traits of the SWAP-200’s clusters A and B disorders than SUD and PD patients, whom presented more severe levels of personality impairment. No differences in the SWAP-200’s cluster C have been found, indicating common personality features in these populations. At levels of specific PDs, MOH patients presented higher obsessive and dysphoric traits, as well as better overall psychological functioning than SUD and PD patients. Conclusions: The study supported the presence of a specific pattern of personality in MOH patients including obsessive (perfectionist) and dysphoric characteristics, as well as good enough psychological resources. No similarities with drug addicted and personality-disordered patients were found. Practitioners’ careful understanding of the personality of MOH patients may be useful to provide more effective treatment strategies and patient-tailored intervention programs
a randomized controlled study
Background Uncertainty persists regarding the optimal ventilatory strategy in
trauma patients developing acute respiratory distress syndrome (ARDS). This
work aims to assess the effects of two mechanical ventilation strategies with
high positive end-expiratory pressure (PEEP) in experimental ARDS following
blunt chest trauma. Methods Twenty-six juvenile pigs were anesthetized,
tracheotomized and mechanically ventilated. A contusion was applied to the
right chest using a bolt-shot device. Ninety minutes after contusion, animals
were randomized to two different ventilation modes, applied for 24 h: Twelve
pigs received conventional pressure-controlled ventilation with moderately low
tidal volumes (VT, 8 ml/kg) and empirically chosen high external PEEP
(16cmH2O) and are referred to as the HP-CMV-group. The other group (n = 14)
underwent high-frequency inverse-ratio pressure-controlled ventilation (HFPPV)
involving respiratory rate of 65breaths · min−1, inspiratory-to-expiratory-
ratio 2:1, development of intrinsic PEEP and recruitment maneuvers, compatible
with the rationale of the Open Lung Concept. Hemodynamics, gas exchange and
respiratory mechanics were monitored during 24 h. Computed tomography and
histology were analyzed in subgroups. Results Comparing changes which occurred
from randomization (90 min after chest trauma) over the 24-h treatment period,
groups differed statistically significantly (all P values for group effect
<0.001, General Linear Model analysis) for the following parameters (values
are mean ± SD for randomization vs. 24-h): PaO2 (100 % O2) (HFPPV 186 ± 82 vs.
450 ± 59 mmHg; HP-CMV 249 ± 73 vs. 243 ± 81 mmHg), venous admixture (HFPPV 34
± 9.8 vs. 11.2 ± 3.7 %; HP-CMV 33.9 ± 10.5 vs. 21.8 ± 7.2 %), PaCO2 (HFPPV
46.9 ± 6.8 vs. 33.1 ± 2.4 mmHg; HP-CMV 46.3 ± 11.9 vs. 59.7 ± 18.3 mmHg) and
normally aerated lung mass (HFPPV 42.8 ± 11.8 vs. 74.6 ± 10.0 %; HP-CMV 40.7 ±
8.6 vs. 53.4 ± 11.6 %). Improvements occurring after recruitment in the HFPPV-
group persisted throughout the study. Peak airway pressure and VT did not
differ significantly. HFPPV animals had lower atelectasis and inflammation
scores in gravity-dependent lung areas. Conclusions In this model of ARDS
following unilateral blunt chest trauma, HFPPV ventilation improved
respiratory function and fulfilled relevant ventilation endpoints for trauma
patients, i.e. restoration of oxygenation and lung aeration while avoiding
hypercapnia and respiratory acidosis
a controlled study design
This study aimed to analyse the impact of an 8-week core strength training (CST) programme in youth karate practitioners on core endurance, agility, flexibility, sprinting, jumping, and kick performance. This study followed a randomized parallel design. Twenty-nine participants (age: 12.86 ± 0.81 years old; height: 152.55 ± 10.37 cm; weight: 42.93 ± 8.85 kg) were allocated to a CST programme (n = 16) performed thrice weekly or to a control group (n = 13) only performing the sport-specific (karate) training. Participants were assessed three times (baseline, mid and post-intervention) for the following tests: (i) flexor endurance test (FET); (ii) back extensor test (BET); (iii) lateral musculature test (LMT); (iv) flexibility; (v) chance of direction (COD); (vi) countermovement jump (CMJ); (vii) back muscle strength (BMS); (viii) horizontal jump (LJ); (ix) sprint test; and (x) karate kick test (KKT). Between-group analysis revealed significant advantages for the CST group on the FET (p 0.05). The within-group changes revealed significant improvements in the CST group at flexibility (p = 0.002), COD (p < 0.001), CMJ (p < 0.001), BMS (p < 0.002), 20 m sprint (p = 0.033), and KKT (p < 0.001). In addition, within-group changes in the control group were also significant in flexibility (p = 0.024) and right kick (p < 0.042). We conclude that the CST programme improves core endurance and karate kick performance; however, it is not effective enough for other physical performance parameters in KR practitioners.9E1A-F9DD-3EB8 | Filipe Manuel ClementeN/
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