29 research outputs found
Boosted Top Quark Pair Production in Soft Collinear Effective Theory
We review a Soft Collinear Effective Theory approach to the study of
factorization and resummation of QCD effects in top-quark pair production. In
particular, we consider differential cross sections such as the top-quark pair
invariant mass distribution and the top-quark transverse momentum and rapidity
distributions. Furthermore, we focus our attention on the large invariant mass
and large transverse momentum kinematic regions, characteristic of boosted top
quarks. We discuss the factorization of the differential cross section in the
double soft gluon emission and small top-quark mass limit, both in Pair
Invariant Mass (PIM) and One Particle Inclusive (1PI) kinematics. The
factorization formulas can be employed in order to implement the simultaneous
resummation of soft emission and small mass effects up to
next-to-next-to-leading logarithmic accuracy. The results are also used to
construct improved next-to-next-to-leading order approximations for the
differential cross sections.Comment: 6 pages. Proceedings of the Second Annual Conference on Large Hadron
Collider Physics (LHCP 2014), Columbia University, New York, June 2-7, 201
The MDRD equation underestimates the prevalence of CKD among blacks and overestimates the prevalence of CKD among whites compared to the CKD-EPI equation: a retrospective cohort study
Abstract Background Black individuals are far more likely than white individuals to develop end stage renal disease (ESRD). However, earlier stages of chronic kidney disease (CKD) have been reported to be less prevalent among blacks. This disparity remains poorly understood. The objective of this study was to evaluate whether the lower prevalence of CKD among blacks in early stages of CKD might be due in part to an inability of the MDRD equation to accurately determine early stages of CKD in both the black and white population. Methods We conducted a retrospective cohort study of 97, 451 patients seen in primary care clinic in Veterans Integrated Service Network 2 (VISN 2) over a 7 year period to determine the prevalence of CKD using both the Modification of Diet in Renal Disease (MDRD) Study equation and the more recently developed CKD Epidemiology Collaboration (CKD-EPI) equation. Demographic data, comorbid conditions, prescription of medications, and laboratory data were recorded. Logistic regression and quantile regression models were used to compare the prevalence of estimated glomerular filtration rate (eGFR) categories between black and white individuals. Results The overall prevalence of CKD was lower when the CKD-EPI equation was used. Prevalence of CKD in whites was 53.2% by MDRD and 48.4% by CKD-EPI, versus 34.1% by MDRD and 34.5% by CKD-EPI in blacks. The cumulative logistic regression and quantile regression showed that when eGFR was calculated by the EPI method, blacks were as likely to present with an eGFR value less than 60 mL/min/1.73 m2 as whites. Using the CKD-EPI equation, blacks were more likely than white individuals to have stage 3b, 4 and 5 CKD. Using the MDRD method, the prevalence in blacks was only higher than in whites for stage 4 and 5 CKD. Similar results were obtained when the analysis was confined to patients over 65 years of age. Conclusions The MDRD equation overestimates the prevalence of CKD among whites and underestimates the prevalence of CKD in blacks compared to the CKD-EPI equation.</p
Patterns of medication use for the treatment of menopausal symptoms before and after the women’s health initiative; implications for decision-making practices of women and women’s health professionals
Baseline characteristic differences between patients prescribed sitagliptin vs. other oral antihyperglycemic agents: analysis of a US electronic medical record database
Inadequate pain relief among patients with primary knee osteoarthritis
ABSTRACT Background: Despite the widespread treatments for osteoarthritis (OA), data on treatment patterns, adequacy of pain relief, and quality of life are limited. The prospective multinational Survey of Osteoarthritis Real World Therapies (SORT) was designed to investigate these aspects. Objectives: To analyze the characteristics and the patient reported outcomes of the Portuguese dataset of SORT at the start of observation. Methods: Patients ≥50 years with primary knee OA who were receiving oral or topical analgesics were eligible. Patients were enrolled from seven healthcare centers in Portugal between January and December 2011. Pain and function were evaluated using the Brief Pain Inventory (BPI) and WOMAC. Quality of life was assessed using the 12-Item Short Form Health Survey (SF-12). Inadequate pain relief (IPR) was defined as a score >4/10 on item 5 of the BPI. Results: Overall, 197 patients were analyzed. The median age was 67.0 years and 78.2% were female. Mean duration of knee OA was 6.2 years. IPR was reported by 51.3% of patients. Female gender (adjusted odds ratio - OR 2.15 [95%CI 1.1, 4.5]), diabetes (OR 3.1 [95%CI 1.3, 7.7]) and depression (OR 2.24 [95%CI 1.2, 4.3]) were associated with higher risk of IPR. Patients with IPR reported worst outcomes in all dimensions of WOMAC (p < 0.001) and in all eight domains and summary components of SF-12 (p < 0.001). Conclusions: Our findings indicate that improvements are needed in the management of pain in knee OA in order to achieve better outcomes in terms of pain relief, function and quality of life
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Full supersymmetry simulation for ATLAS in DC1
This note reports results from a simulation of 100k events for one example of a minimal SUGRA supersymmetry case at the LHC using full simulation of the ATLAS detector. It was carried out as part ATLAS Data Challenge 1