6,059 research outputs found
A Growing Commonality Among Lutherans?
A statistical report from the Office of LCUSA shows that as of February 1970 there were 50 pan-Lutheran councils and conferences of various sorts in operation, representing 27 states, and another 39 in the process of formation, including 6 additional states. The great majority of these councils have come into existence in major metropolitan centers
Reliability-Based Design of Thermal Protection Systems with Support Vector Machines
The primary objective of this work was to develop a computationally efficient and accurate approach to reliability analysis of thermal protection systems using support vector machines. An adaptive sampling approach was introduced informs a iterative support vector machine approximation of the limit state function used for measuring reliability. The proposed sampling approach efficient adds samples along the limit state function until the reliability approximation is converged. This methodology is applied to two samples, mathematical functions to test and demonstrate the applicability. Then, the adaptive sampling-based support vector machine approach is applied to the reliability analysis of a thermal protection system. The results of all three problems highlight the potential capability of the new approach in terms of accuracy and computational saving in determining thermal protection system reliability
Calibration Probe Uncertainty and Validation for the Hypersonic Material Environmental Test System
This paper presents an uncertainty analysis of the stagnation-point calibration probe surface predictions for conditions that span the performance envelope of the Hypersonic Materials Environmental Test System facility located at NASA Langley Research Center. A second-order stochastic expansion was constructed over 47 uncertain parameters to evaluate the sensitivities, identify the most significant uncertain variables, and quantify the uncertainty in the stagnation-point heat flux and pressure predictions of the calibration probe for a low- and high-enthalpy test condition. A sensitivity analysis showed that measurement bias uncertainty is the most significant contributor to the stagnation-point pressure and heat flux variance for the low-enthalpy condition. For the high-enthalpy condition, a paradigm shift in sensitivities revealed the computational fluid dynamics model input uncertainty as the main contributor. A comparison between the prediction and measurement of the stagnation-point conditions under uncertainty showed that there was evidence of statistical disagreement. A validation metric was proposed and applied to the prediction uncertainty to account for the statistical disagreement when compared to the possible stagnation-point heat flux and pressure measurements
Virtual knot groups and almost classical knots
We define a group-valued invariant of virtual knots and relate it to various
other group-valued invariants of virtual knots, including the extended group of
Silver-Williams and the quandle group of Manturov and Bardakov-Bellingeri. A
virtual knot is called almost classical if it admits a diagram with an
Alexander numbering, and in that case we show that the group factors as a free
product of the usual knot group and Z. We establish a similar formula for mod p
almost classical knots, and we use these results to derive obstructions to a
virtual knot K being mod p almost classical. Viewed as knots in thickened
surfaces, almost classical knots correspond to those that are homologically
trivial. We show they admit Seifert surfaces and relate their Alexander
invariants to the homology of the associated infinite cyclic cover. We prove
the first Alexander ideal is principal, recovering a result first proved by
Nakamura et al. using different methods. The resulting Alexander polynomial is
shown to satisfy a skein relation, and its degree gives a lower bound for the
Seifert genus. We tabulate almost classical knots up to 6 crossings and
determine their Alexander polynomials and virtual genus.Comment: 44 page
Sarcoidosis presenting as granulomatous myositis in a 16-year-old adolescent
BACKGROUND: Sarcoidosis is a multi-system disease characterized by the presence of non-caseating epithelioid granulomas in affected tissues, including skeletal muscle. These organized collections of immune cells have important pathophysiologic action including cytokine production leading to inflammation as well as enzymatic conversion of cholecalciferol to calcitriol via 1-α hydroxylase. There are limited reports of isolated granulomatous myositis causing hypercalcemia in pediatric patients. Our patient uniquely presented with symptoms from hypercalcemia and renal insufficiency caused by an overwhelming burden of granulomatous myositis in her lower extremities, but was otherwise asymptomatic. CASE PRESENTATION: A 16 year old Caucasian female presented with protracted symptoms of fatigue, nausea and prominent weight loss with laboratory evidence of hypercalcemia and renal insufficiency. She lacked clinical and physical findings of arthritis, weakness, rash, uveitis, fever, lymphadenopathy or respiratory symptoms. After extensive negative investigations, re-examination yielded subtle soft tissue changes in her lower extremities, with striking MRI findings of extensive myositis without correlative weakness or serum enzyme elevation. Biopsy showed the presence of non-caseating epithelioid granulomas and calcium oxalate crystals. The patient responded well to prednisone and methotrexate but relapsed with weaning of steroids. She reachieved remission with addition of adalimumab. CONCLUSIONS: Sarcoidosis should be considered in patients presenting with symptomatic hypercalcemia with no apparent causes and negative routine workup. The absences of decreased muscle strength or elevated muscle enzymes do not preclude the diagnosis of granulomatous myositis
The Indy Racing League and the Indianapolis 500: Increasing Competition in Open-Wheeled Automobile Racing in the United States
Over the course of its lengthy history, the popularity of open-wheeled automobile racing in the United States has waxed and waned. This is especially evident in recent years. The 1996 “split” between the Indy Racing League (IRL; later, the IndyCar Series) and Championship Auto Racing Teams (CART; later the Champ Car World Series) severely hurt the sport. Following the split there was a well-documented decline in fan interest from which the sport has not recovered. Less understood, however, is that under the Indy Racing League the Indianapolis 500, the premier event in open-wheeled racing in the United States, became more competitive. Ironically, while fan interest decreased in the Indy Racing League era, the quality of racing increased. The increased competition associated with the Indy Racing League is a historically significant development that bodes well for the future of the sport
An assessment of residents’ and fellows’ personal finance literacy: An unmet medical education need
Objectives: This study aimed to assess residents' and fellows' knowledge of finance principles that may affect their personal financial health. Methods: A cross-sectional, anonymous, web-based survey was administered to a convenience sample of residents and fellows at two academic medical centers. Respondents answered 20 questions on personal finance and 28 questions about their own financial planning, attitudes, and debt. Questions regarding satisfaction with one's financial condition and investment-risk tolerance used a 10-point Likert scale (1=lowest, 10=highest). Of 2,010 trainees, 422 (21%) responded (median age 30 years; interquartile range, 28-33). Results: The mean quiz score was 52.0% (SD = 19.1). Of 299 (71%) respondents with student loan debt, 144 (48%) owed over 25,000. Respondents' mean satisfaction with their current personal financial condition was 4.8 (SD = 2.5) and investment-risk tolerance was 5.3 (SD = 2.3). Indebted trainees reported lower satisfaction than trainees without debt (4.4 vs. 6.2, F (1,419) = 41.57, p < .001). Knowledge was moderately correlated with investment-risk tolerance (r=0.41, p < .001), and weakly correlated with satisfaction with financial status (r=0.23, p < .001). Conclusions: Residents and fellows had low financial literacy and investment-risk tolerance, high debt, and deficits in their financial preparedness. Adding personal financial education to the medical education curriculum would benefit trainees. Providing education in areas such as budgeting, estate planning, investment strategies, and retirement planning early in training can offer significant long-term benefits.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Characterizing quantum dynamics with initial system-environment correlations
We fully characterize the reduced dynamics of an open quantum system
initially correlated with its environment. Using a photonic qubit coupled to a
simulated environment we tomographically reconstruct a superchannel---a
generalised channel that treats preparation procedures as inputs---from
measurement of the system alone, despite its coupling to the environment. We
introduce novel quantitative measures for determining the strength of initial
correlations, and to allow an experiment to be optimised in regards to its
environment.Comment: 10 pages, 15 figure
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