551 research outputs found
A model of non-perturbative gluon emission in an initial state parton shower
We consider a model of transverse momentum production in which
non-perturbative smearing takes place throughout the perturbative evolution, by
a simple modification to an initial state parton shower algorithm. Using this
as the important non-perturbative ingredient, we get a good fit to data over a
wide range of energy. Combining it with the non-perturbative masses and cutoffs
that are a feature of conventional parton showers also leads to a reasonable
fit. We discuss the extrapolation to the LHC.Comment: 14 pages, 6 figures; version accepted by JHE
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Association of the rs2242446 polymorphism in the norepinephrine transporter gene SLC6A2 and anxious arousal symptoms of posttraumatic stress disorder
To the Editor: Recently, we found that greater norepinephrine transporter (NET) availability in the locus ceruleus of trauma survivors with posttraumatic stress disorder (PTSD) was associated with increased severity of anxious arousal (ie, hypervigilance and exaggerated startle) symptoms, but not any of the other empirically derived symptom clusters that characterize this disorder.1 This finding suggests that greater NET availability in the locus ceruleus may serve a compensatory function of clearing elevated synaptic norepinephrine and maintaining anxious arousal symptoms in persons with PTSD
Association of the rs2242446 polymorphism in the norepinephrine transporter gene SLC6A2 and anxious arousal symptoms of posttraumatic stress disorder
To the Editor: Recently, we found that greater norepinephrine transporter (NET) availability in the locus ceruleus of trauma survivors with posttraumatic stress disorder (PTSD) was associated with increased severity of anxious arousal (ie, hypervigilance and exaggerated startle) symptoms, but not any of the other empirically derived symptom clusters that characterize this disorder.1 This finding suggests that greater NET availability in the locus ceruleus may serve a compensatory function of clearing elevated synaptic norepinephrine and maintaining anxious arousal symptoms in persons with PTSD
Joint statement on the role of respiratory rehabilitation in the COVID-19 crisis: the Italian position paper.
Due to an exponential growth of the number of subjects affected by coronavirus disease 2019 (COVID-19), the entire Italian healthcare system had to respond promptly and in a very short time with the need of semi-intensive and intensive care units. Moreover, trained dedicated COVID-19 teams consisting of physicians coming from different specialties (intensivists or pneumologists and infectivologists), while respiratory therapists and nurses have been recruited to work on and on with rest.
However, due to still limited and evolving knowledge of COVID-19 disease, there are little recommendations for need in respiratory rehabilitation and physiotherapy interventions. The presentation of this manuscript is the result of a consensus promoted by the Italian societies of respiratory health care professionals who contacted pulmonologists directly involved in the treatment and rehabilitation of COVID-19. The aim was to formulate the more proper and common suggestions to be applied in different hospital settings in offering rehabilitative programs and physiotherapy workforce planning in COVID-19 patients.
Two main areas of intervention were identified: organization and treatment, which were described in this paper to face with the emergency
Characterization of grape (Vitis vinifera L.) berry sunburn symptoms by reflectance
Sunburn can affect grape quality both for chemical modifications and by visual impact of the browning. Optical properties of 17 white grape accessions were investigated in the visible region using a noninvasive instrument. Reflectance spectra were obtained using a Jaz System spectrometer. Browning was induced by exposing grape bunches to direct sunlight at 12:30 p.m. for 5 h. During the experiment, the global solar radiation ranged from 2.6 to 2.7 MJ m-2 h-1 and the air temperature from 24.3 to 29.2 \ub0C; the exposed berries reached a temperature of 34.2 \ub0C in comparison to the 30.4 \ub0C of the shaded ones. Differences between the spectra of controlled and exposed berries mainly emphasized the loss in chlorophyll and the formation of brown compounds. A positive correlation between the chlorophyll concentration and berry browning was proposed. Developing rapid, noninvasive, and low-cost methods based on reflectance spectroscopy could support grapevine variety characterization with respect to sunburn susceptibility as well as study of the physiological processes involved in the symptoms' appearance
Non-perturbative effects and the resummed Higgs transverse momentum distribution at the LHC
We investigate the form of the non-perturbative parameterization in both the
impact parameter (b) space and transverse momentum (p_T) space resummation
formalisms for the transverse momentum distribution of single massive bosons
produced at hadron colliders. We propose to analyse data on Upsilon
hadroproduction as a means of studying the non-perturbative contribution in
processes with two gluons in the initial state. We also discuss the theoretical
errors on the resummed Higgs transverse momentum distribution at the LHC
arising from the non-perturbative contribution.Comment: 22 pages, 10 figure
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Evaluating the structure and magnitude of the ash plume during the initial phase of the 2010 Eyjafjallajökull eruption using lidar observations and NAME simulations
The Eyjafjallajökull volcano in Iceland erupted explosively on 14 April 2010, emitting a plume of ash into the atmosphere. The ash was transported from Iceland toward Europe where mostly cloud-free skies allowed ground-based lidars at Chilbolton in England and Leipzig in Germany to estimate the mass concentration in the ash cloud as it passed overhead. The UK Met Office's Numerical Atmospheric-dispersion Modeling Environment (NAME) has been used to simulate the evolution of the ash cloud from the Eyjafjallajökull volcano during the initial phase of the ash emissions, 14–16 April 2010. NAME captures the timing and sloped structure of the ash layer observed over Leipzig, close to the central axis of the ash cloud. Relatively small errors in the ash cloud position, probably caused by the cumulative effect of errors in the driving meteorology en route, result in a timing error at distances far from the central axis of the ash cloud. Taking the timing error into account, NAME is able to capture the sloped ash layer over the UK. Comparison of the lidar observations and NAME simulations has allowed an estimation of the plume height time series to be made. It is necessary to include in the model input the large variations in plume height in order to accurately predict the ash cloud structure at long range. Quantitative comparison with the mass concentrations at Leipzig and Chilbolton suggest that around 3% of the total emitted mass is transported as far as these sites by small (<100 μm diameter) ash particles
A multicenter retrospective clinical study of CD5/CD10-negative chronic B cell leukemias.
CD5-negative chronic B cell lymphoproliferative disorders in leukemic phase (B-CLPD) are heterogeneous and relatively uncommon pathologies that often lack a histopathological definition because of the absence of accessible pathological tissue. We describe the clinical features and evolution-related variables of 156 patients with CD5/CD10-negative B-CLPD (median age 66 years, range 25-86). The median follow-up was 51 months (range 6-216), and overall 3- and 5-year survival was respectively 87 and 76%; 50 patients needed therapy at diagnosis, 56 during follow-up, and 50 remained untreated until the last control. A combined clinical, histological, cytomorphological, immunophenotypical, and cytogenetic diagnostic approach allowed the complete classification of only a minority of patients as being affected by splenic marginal zone or lymphoplasmacytic lymphoma; the majority of cases remained unclassifiable. Multivariate analysis showed that the clinicohematological variables adversely related to overall survival were serum LDH levels and age, whereas high serum LDH levels, hemoglobin levels of <11 g/dl, and splenomegaly related to treatment-free time (in "wait and see" cases); only splenomegaly related to time to progression (in treated patients). In conclusion, our retrospective study describes the clinical features and variables related to evolution in a large group of patients with CD5/CD10-negative chronic B-cell lymphoid leukemias and underlines the fact that a probable lymphoplasmacytic or marginal zone normal cell origin can be supposed in such leukemic forms, but never surely demonstrated
Steps towards the hyperfine splitting measurement of the muonic hydrogen ground state: pulsed muon beam and detection system characterization
The high precision measurement of the hyperfine splitting of the
muonic-hydrogen atom ground state with pulsed and intense muon beam requires
careful technological choices both in the construction of a gas target and of
the detectors. In June 2014, the pressurized gas target of the FAMU experiment
was exposed to the low energy pulsed muon beam at the RIKEN RAL muon facility.
The objectives of the test were the characterization of the target, the
hodoscope and the X-ray detectors. The apparatus consisted of a beam hodoscope
and X-rays detectors made with high purity Germanium and Lanthanum Bromide
crystals. In this paper the experimental setup is described and the results of
the detector characterization are presented.Comment: 22 pages, 14 figures, published and open access on JINS
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