159 research outputs found
NLO QCD corrections to hadronic Higgs production with heavy quarks
The production of a Higgs boson in association with a pair of top-antitop or
bottom-antibottom quarks plays a very important role at both the Tevatron and
the Large Hadron Collider. The theoretical prediction of the corresponding
cross sections has been improved by including the complete next-to-leading
order QCD corrections. After a brief description of the most relevant technical
aspects of the calculation, we review the results obtained for both the
Tevatron and the Large Hadron ColliderComment: 6 pages, 6 figures, espcrc2.sty. Talk given at the International
Conference QCD03, 2-7 July 2003, Montpellier, France. To be published in
Nucl. Phys. B Proc. Supp
Magnetic Field Structures in a Facular Region Observed by THEMIS and Hinode
The main objective of this paper is to build and compare vector magnetic maps
obtained by two spectral polarimeters, i.e. THEMIS/MTR and Hinode SOT/SP, using
two inversion codes (UNNOFIT and MELANIE) based on the Milne-Eddington solar
atmosphere model. To this end, we used observations of a facular region within
active region NOAA 10996 on 23 May 2008, and found consistent results
concerning the field strength, azimuth and inclination distributions. Because
SOT/SP is free from the seeing effect and has better spatial resolution, we
were able to resolve small magnetic polarities with sizes of 1" to 2", and we
could detect strong horizontal magnetic fields, which converge or diverge in
negative or positive facular polarities. These findings support models which
suggest the existence of small vertical flux tube bundles in faculae. A new
method is proposed to get the relative formation heights of the multi-lines
observed by MTR assuming the validity of a flux tube model for the faculae. We
found that the Fe 1 6302.5 \AA line forms at a greater atmospheric height than
the Fe 1 5250.2 \AA line.Comment: 20 pages, 9 figures, 3 tables, accepted for publication in Solar
Physic
First measurement of direct photoproduction on the proton
We report on the results of the first measurement of exclusive
meson photoproduction on protons for GeV and GeV. Data were collected with the CLAS detector at the Thomas
Jefferson National Accelerator Facility. The resonance was detected via its
decay in the channel by performing a partial wave analysis of the
reaction . Clear evidence of the meson
was found in the interference between and waves at GeV. The -wave differential cross section integrated in the mass range of
the was found to be a factor of 50 smaller than the cross section
for the meson. This is the first time the meson has been
measured in a photoproduction experiment
Insertional mutation of the hairless locus on mouse Chromosome 14
Crosses between heterozygous transgenic mice from line 5053 produced offspring with progressive irreversible hair loss beginning at day 10. With increasing age, the skin of these animals became thicker and plicated in appearance. Histological analysis revealed the complete absence of normal hair follicles and numerous intradermic cystic structures, which enlarged with time and became filled with keratinaceous material. Test crosses demonstrated that the affected animals are homozygous for the transgene insertion. The clinicla and histological phenotype of the new mutant closely resembles that of the rhino allele at the hairless locus on Chromosome (Chr) 14. Complementation tests and linkage analysis indicate that the transgene has interrupted the hairless locus. It has been demonstrated previously that mutation at the hr locus is accompanied by a variety of immune deficiencies. Many of the older affected transgenic mice developed an impetigo-like skin eruption which responded to antibiotic ointment and which may reflect impaired immune function. The transgenic allele, hr TgN5053Mm , will be useful for identification of the transcription unit of the hairless locus.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47000/1/335_2004_Article_BF00360900.pd
Patient-reported ability to walk 4Â m and to wash: New clinical endpoints and predictors of survival in patients with pre-terminal cancer
BACKGROUND: Maintaining the ability to perform self-care is a critical goal in patients with cancer. We assessed whether the patient-reported ability to walk 4 m and wash oneself predict survival in patients with pre-terminal cancer. METHODS: We performed a prospective observational study on 169 consecutive hospitalized patients with cancer (52% female, 64 ± 12 years) and an estimated 1-12 months prognosis at an academic, inpatient palliative care unit. Patients answered functional questions for 'today', 'last week', and 'last month', performed patient-reported outcomes (PROs), and physical function assessments. RESULTS: Ninety-two (54%) patients reported the ability to independently walk 4 m and 100 (59%) to wash 'today'. The median number of days patients reported the ability to walk 4 m and wash were 6 (IQR 0-7) and 7 (0-7) days ('last week'); and 27 (5-30) and 26 (10-30) days ('last month'). In the last week, 32% of patients were unable to walk 4 m on every day and 10% could walk on 1-3 days; 30% were unable to wash on every day and 10% could wash on 1-3 days. In the last months, 14% of patients were unable to walk 4 m on every day and 10% could only walk on 1-10 days; 12% were unable to wash on every day and 11% could wash on 1-10 days. In patients who could walk 'today' average 4 m gait speed was 0.78 ± 0.28 m/s. Patients who reported impaired walking and washing experienced more symptoms (dyspnoea, exertion, and oedema) and decreased physical function (higher Eastern Cooperative Oncology Group Performance Status, and lower Karnofsky Performance Status and hand-grip strength [unable vs. able to walk 'today': 205 ± 87 vs. 252 ± 78 Newton, P = 0.001; unable vs. able to wash 'today': 204 ± 86 vs. 250 ± 80 Newton, P = 0.001]). During the 27 months of observation, 152 (90%) patients died (median survival 46 days). In multivariable Cox proportional hazards regression analyses, all tested parameters were independent predictors of survival: walking 4 m 'today' (HR 0.63, P = 0.015), 'last week' (per 1 day: HR 0.93, P = 0.011), 'last month' (per 1 day: HR 0.98, P = 0.012), 4 m gait speed (per 1 m/s: HR 0.45, P = 0.002), and washing 'today' (HR 0.67, P = 0.024), 'last week (per 1 day HR 0.94, p=0.019), and 'last month' (per 1 day HR 0.99, P = 0.040). Patients unable to walk and wash experienced the shortest survival and most reduced functional status. CONCLUSIONS: In patients with pre-terminal cancer, the self-reported ability to walk 4 m and wash were independent predictors of survival and associated with decreased functional status
Linear Collider Physics Resource Book for Snowmass 2001, 3: Studies of Exotic and Standard Model Physics
This Resource Book reviews the physics opportunities of a next-generation e+e- linear collider and discusses options for the experimental program. Part 3 reviews the possible experiments on that can be done at a linear collider on strongly coupled electroweak symmetry breaking, exotic particles, and extra dimensions, and on the top quark, QCD, and two-photon physics. It also discusses the improved precision electroweak measurements that this collider will make available.This Resource Book reviews the physics opportunities of a next-generation e+e- linear collider and discusses options for the experimental program. Part 3 reviews the possible experiments on that can be done at a linear collider on strongly coupled electroweak symmetry breaking, exotic particles, and extra dimensions, and on the top quark, QCD, and two-photon physics. It also discusses the improved precision electroweak measurements that this collider will make available
Characteristics of Early-Onset vs Late-Onset Colorectal Cancer: A Review.
The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer.
Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts.
The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes
Measurement of the cross section for isolated-photon plus jet production in pp collisions at âs=13 TeV using the ATLAS detector
The dynamics of isolated-photon production in association with a jet in protonâproton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fbâ1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photonâjet invariant mass and the scattering angle in the photonâjet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements
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