1,773 research outputs found
Simulation Application for the LHCb Experiment
We describe the LHCb detector simulation application (Gauss) based on the
Geant4 toolkit. The application is built using the Gaudi software framework,
which is used for all event-processing applications in the LHCb experiment. The
existence of an underlying framework allows several common basic services such
as persistency, interactivity, as well as detector geometry description or
particle data to be shared between simulation, reconstruction and analysis
applications. The main benefits of such common services are coherence between
different event-processing stages as well as reduced development effort. The
interfacing to Geant4 toolkit is realized through a facade (GiGa) which
minimizes the coupling to the simulation engine and provides a set of abstract
interfaces for configuration and event-by-event communication. The Gauss
application is composed of three main blocks, i.e. event generation, detector
response simulation and digitization which reflect the different stages
performed during the simulation job. We describe the overall design as well as
the details of Gauss application with a special emphasis on the configuration
and control of the underlying simulation engine. We also briefly mention the
validation strategy and the planing for the LHCb experiment simulation.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 6 pages, LaTeX, 9 eps figures. PSN
TUMT00
The differential impact of two anesthetic techniques on cortisol levels in Nigerian surgical patients
Background: Surgical procedures are associated with a complexity of stress response characterized by neurohumoral, immulogic, and metabolic alterations. Aim: The aim was to compare the effects on the stress response by isoflurane‑based intratracheal general anesthesia (ITGA) and bupivacaine‑based epidural anesthesia (EA), using cortisol as a biochemical marker. Materials and Methods: Following the approval of the Hospital Ethical Board, informed written consent from patients recruited into this study was obtained. One group received general anesthesia with relaxant technique (group A) while the other group had bupicaine epidural anesthesia with catheter placement for top‑ups (group B) for their surgeries. Both groups were assessed for plasma cortisol levels – baseline, 30 minutes after skin the start of surgery and at skin closure. Results: There was no statistically significant difference in the baseline mean heart rate, mean arterial pressure (mean MAP) and the mean duration of surgery between the two groups; the baseline mean plasma cortisol level was 88.70 ± 3.85 ng/ml for group A and 85.55 ± 2.29 ng/ml for group B, P=0.148. At 30 minutes after the start of surgery the plasma cortisol level in the GA group was 361.60 ± 31.27 ng/ml while it was 147.45 ± 22.36 ng/ml in the EA group, showing a significant difference, P=0.001. At skin closure the mean plasma cortisol value of 384.65 ± 48.04 ng/ml recorded in the GA group was found to be significantly higher than the value of 140.20 ± 10.74 ng/ml in the GA group, P<0.002. Conclusion: Using plasma cortisol as a measure, bupivacaine‑based epidural anesthesia significantly reduces the stress response to surgical stimuli when compared with isoflurane‑based tracheal general anesthesia.Keywords: Cortisol levels, epidural anesthesia, general anesthesia, surgeryNigerian Journal of Clinical Practice •Jan-Mar 2012 • Vol 15 • Issue
Comparison of maternal satisfaction following epidulral and general anaesthesia for repeat caesarean section
Objective: To assess maternal satisfaction following two anaesthetic techniques (general and epidural anaesthesia) for repeat Caesarean section.Design: Prospective study.Setting: University of Port Harcourt Teaching Hospital, Nigeria.Subjects: One hundred and twenty parturients scheduled for elective Caesarean section.Results: The demographic data and mean satisfaction scores obtained from questionnaire and visual analogue scale (VAS) were subjected to analysis using the Student’s t-test with the computerised statistical calculator SPSS Windows 10.0. The mean satisfaction score of the parturients in the epidural anaesthesia population using the questionnaire was 149.0±10.65 while that in the general anaesthesia population was 105.3±12.42. The mean satisfaction score from the VAS was 9.0±1.50 for those who had epidural anaesthesia while it was 2.6±0.70 in the general anaesthesia population. The differences in the mean satisfaction scores from both instruments of measurement were statistically significant at
Large ferroelectric polarization in the new double perovskite NaLaMnWO induced by non-polar instabilities
Based on density functional theory calculations and group theoretical
analysis, we have studied NaLaMnWO compound which has been recently
synthesized [Phys. Rev. B 79, 224428 (2009)] and belongs to the family of double perovskites. At low temperature, the structure has
monoclinic symmetry, with layered ordering of the Na and La ions and
rocksalt ordering of Mn and W ions. The Mn atoms show an antiferromagnetic
(AFM) collinear spin ordering, and the compound has been reported as a
potential multiferroic. By comparing the low symmetry structure with a parent
phase of symmetry, two distortion modes are found dominant. They
correspond to MnO and WO octahedron \textit{tilt} modes, often
found in many simple perovskites. While in the latter these common tilting
instabilities yield non-polar phases, in NaLaMnWO the additional presence
of the - cation ordering is sufficient to make these rigid unit modes
as a source of the ferroelectricity. Through a trilinear coupling with the two
unstable tilting modes, a significant polar distortion is induced, although the
system has no intrinsic polar instability. The calculated electric polarization
resulting from this polar distortion is as large as 16 . Despite its secondary character, this polarization is coupled with
the dominant tilting modes and its switching is bound to produce the switching
of one of two tilts, enhancing in this way a possible interaction with the
magnetic ordering. The transformation of common non-polar purely steric
instabilities into sources of ferroelectricity through a controlled
modification of the parent structure, as done here by the cation ordering, is a
phenomenon to be further explored.Comment: Physical Chemistry Chemical physics (in press
Modifications of Gait as Predictors of Natural Osteoarthritis Progression in STR/Ort Mice
OBJECTIVE: Osteoarthritis (OA) is a common chronic disease for which disease-modifying therapies are not currently available. Studies to seek new targets for slowing the progress of OA rely on mouse models, but these do not allow for longitudinal monitoring of disease development. This study was undertaken to determine whether gait can be used to measure disease severity in the STR/Ort mouse model of spontaneous OA and whether gait changes are related to OA joint pain. METHODS: Gait was monitored using a treadmill-based video system. Correlations between OA severity and gait at 3 treadmill speeds were assessed in STR/Ort mice. Gait and pain behaviors of STR/Ort mice and control CBA mice were analyzed longitudinally, with monthly assessments. RESULTS: The best speed to identify paw area changes associated with OA severity in STR/Ort mice was found to be 17 cm · seconds(−1). Paw area was modified with age in CBA and STR/Ort mice, but this began earlier in STR/Ort mice and correlated with the onset of OA at 20 weeks of age. In addition, task noncompliance appeared at 20 weeks. Surprisingly, STR/Ort mice did not show any signs of pain with OA development, even when treated with the opioid antagonist naloxone, but did exhibit normal pain behaviors in response to complete Freund's adjuvant–induced arthritis. CONCLUSION: The present results identify an animal model in which OA severity and OA pain can be studied in isolation from one another. The findings suggest that paw area and treadmill noncompliance may be useful tools to longitudinally monitor nonpainful OA development in STR/Ort mice. This will help in providing a noninvasive means of assessing new therapies to slow the progression of OA
Characterizing and prognosticating chronic lymphocytic leukemia in the elderly: prospective evaluation on 455 patients treated in the United States.
BACKGROUND: Median age at diagnosis of patients with chronic lymphocytic leukemia (CLL) is \u3e 70 years. However, the majority of clinical trials do not reflect the demographics of CLL patients treated in the community. We examined treatment patterns, outcomes, and disease-related mortality in patients ≥ 75 years with CLL (E-CLL) in a real-world setting.
METHODS: The Connect® CLL registry is a multicenter, prospective observational cohort study, which enrolled 1494 adult patients between 2010-2014, at 199 US sites. Patients with CLL were enrolled within 2 months of initiating first line of therapy (LOT1) or a subsequent LOT (LOT ≥ 2). Kaplan-Meier methods were used to evaluate overall survival. CLL- and infection-related mortality were assessed using cumulative incidence functions (CIF) and cause-specific hazards. Logistic regression was used to develop a classification model.
RESULTS: A total of 455 E-CLL patients were enrolled; 259 were enrolled in LOT1 and 196 in LOT ≥ 2. E-CLL patients were more likely to receive rituximab monotherapy (19.3 vs. 8.6%; p \u3c 0.0001) and chemotherapy-alone regimens (p \u3c 0.0001) than younger patients. Overall and complete responses were lower in E-CLL patients than younger patients when given similar regimens. With a median follow-up of 3 years, CLL-related deaths were higher in E-CLL patients than younger patients in LOT1 (12.6 vs. 5.1% p = 0.0005) and LOT ≥ 2 (31.3 vs. 21.5%; p = 0.0277). Infection-related deaths were also higher in E-CLL patients than younger patients in LOT1 (7.4 vs. 2.7%; p = 0.0033) and in LOT ≥ 2 (16.2 vs. 11.2%; p = 0.0786). A prognostic score for E-CLL patients was developed: time from diagnosis to treatment \u3c 3 months, enrollment therapy other than bendamustine/rituximab, and anemia, identified patients at higher risk of inferior survival. Furthermore, higher-risk patients experienced an increased risk of CLL- or infection-related death (30.6 vs 10.3%; p = 0.0006).
CONCLUSION: CLL- and infection-related mortality are higher in CLL patients aged ≥ 75 years than younger patients, underscoring the urgent need for alternative treatment strategies for these understudied patients.
TRIAL REGISTRATION: The Connect CLL registry was registered at clinicaltrials.gov: NCT01081015 on March 4, 2010
- …