4,055 research outputs found
Variational Formulation of Macro-Particle Models for Electromagnetic Plasma Simulations
A variational method is used to derive a self-consistent macro-particle model
for relativistic electromagnetic kinetic plasma simulations. Extending earlier
work [E. G. Evstatiev and B. A. Shadwick, J. Comput. Phys., vol. 245, pp.
376-398, 2013], the discretization of the electromagnetic Low Lagrangian is
performed via a reduction of the phase-space distribution function onto a
collection of finite-sized macro-particles of arbitrary shape and
discretization of field quantities onto a spatial grid. This approach may be
used with both lab frame coordinates or moving window coordinates; the latter
can greatly improve computational efficiency for studying some types of
laser-plasma interactions. The primary advantage of the variational approach is
the preservation of Lagrangian symmetries, which in our case leads to energy
conservation and thus avoids difficulties with grid heating. Additionally, this
approach decouples particle size from grid spacing and relaxes restrictions on
particle shape, leading to low numerical noise. The variational approach also
guarantees consistent approximations in the equations of motion and is amenable
to higher order methods in both space and time. We restrict our attention to
the 1-1/2 dimensional case (one coordinate and two momenta). Simulations are
performed with the new models and demonstrate energy conservation and low
noise.Comment: IEEE Transaction on Plasma Science (TPS) Special Issue: Plenary and
Invited Papers of the Pulsed Power and Plasma Science Conference (PPPS 2013
Do BRAF Inhibitors Improve Survival in Patients With BRAF V600E Mutant Melanoma?
OBJECTIVE: The objective of this selective EBM review is to determine whether or not “Do BRAF inhibitors improve survival in patients with BRAF V600E mutant melanoma?”
STUDY DESIGN: Review of primary literature sources that examined survival rates in BRAF V600E mutant melanoma patients receiving treatment with a BRAF inhibitor.
DATA SOURCES: Two randomized controlled trials and one cohort study evaluating the use of BRAF inhibitors in patients with BRAF V600E mutant melanoma were found using OVID, Medline, and PubMed.
OUTCOMES MEASURED: Overall survival and progression free survival were the outcomes measured to determine survival rates in patients with BRAF V600E mutant melanoma.
RESULTS: Chapman et al demonstrates an overall survival rate of 84% for Vemurafenib (95% CI, 78-89) compared to 64% for Dacarbazine (95% CI, 56-73). Progression free survival was 5.3 months for Vemurafenib compared to 1.6 months for Dacarbazine. Sosman et al, a cohort study, demonstrates an overall survival rate of 58% (95% CI, 49-67) after 12 months. Progression free survival was 6.8 months (95% CI, 5.6-8.1). Hauschild et al demonstrates an overall survival rate of 57% for Dabrafenib compared to 22% for Dacarbazine. Progression free survival was 5.1 months for Dabrafenib compared to 2.7 months for Dacarbazine.
CONCLUSIONS: All studies reported longer periods of progression free survival and an increase in overall response rates. This suggests that BRAF inhibitors improve survival in patients with V600E mutant melanoma
Role of critical spin fluctuations in ultrafast demagnetization of transition-metal rare-earth alloys
Ultrafast magnetization dynamics induced by femtosecond laser pulses have
been measured in ferrimagnetic Co0.8Gd0.2, Co.74Tb.26 and Co.86Tb.14 alloys.
Using element sensitivity of X-ray magnetic circular dichroism at the Co L3, Tb
M5 and Gd M5 edges we evidence that the demagnetization dynamics is element
dependent. We show that a thermalization time as fast as 280 fs is observed for
the rare-earth in the alloy, when the laser excited state temperature is below
the compensation temperature. It is limited to 500 fs when the laser excited
state temperature is below the Curie temperature (Tc). We propose critical spin
fluctuations in the vicinity of TC as the mechanism which reduces the
demagnetization rates of the 4f electrons in transition-metal rare-earth alloys
whereas at any different temperature the limited demagnetization rates could be
avoided.Comment: 11 pages, 4 figure
Pediatric Psychologists’ Career Satisfaction: 2015 Society of Pediatric Psychology Workforce Survey Results.
Little is known about the career satisfaction of pediatric psychologists, who specialize in psychological research, teaching, and clinical service in the context of pediatric health care. As part of the larger Society of Pediatric Psychology Workforce Survey and in collaboration with the American Psychological Association Center for Workforce Studies, this study aimed to (1) describe the career domains which pediatric psychologists perceive to be important and their satisfaction in each domain, and (2) compare satisfaction of pediatric psychologists across work settings, number of positions, appointment duration, professional roles, career stage, academic rank, and gender. Responses from 336 pediatric psychologists demonstrated high career satisfaction. Domains of career satisfaction that received mean scores indicating high importance include balance of work and personal lives, peer/collegial support, and flexibility and choice in the workplace, but on average respondents reported being only somewhat satisfied in these domains. Total satisfaction scores were significantly higher among pediatric psychologists in 9–10-month appointments, primarily research careers, and at higher academic ranks, but scores were similar across employment settings and genders. To enhance career satisfaction and retention, pediatric psychologists may seek additional mentorship or explore new employment roles, and administrators and managers may consider adopting workplace policies or making environmental changes that could address specific areas of need
Edward Byrne Memorial Justice Grant, Nebraska Strategic Plan, 2012-2015
The Consortium for Crime and Justice Research (CCJR) at the University of Nebraska at Omaha was tasked by the Nebraska Commission on Law Enforcement and Criminal Justice to facilitate the development of a three-year strategic plan for the use of Edward Byrne Memorial Justice Assistant Grant (JAG) funds. The Crime Commission serves as the State Administering Agency that is responsible for funding projects that fit into one or more of the seven JAG purpose areas: law enforcement programs; planning, evaluation, and technology improvement programs; prevention and education programs; drug treatment and enforcement programs; corrections and community corrections programs; prosecution and court programs; and crime victim and witness programs
An Analysis of U.S. Student Drug and Alcohol Policies through the Lens of a Professional Ethic for School Leadership
This study explored the moral complexity of student drug and alcohol policies that are often disciplinary, punitive, and exclusionary in nature. The Ethic of the Profession (Shapiro & Stefkovich, 2001, 2005, 2010; Stefkovich, 2006), a professional ethical construct for educational leadership and for school workers writ large, was employed as a theoretical framework to evaluate a bounded case of seven school districts’ pupil policies. This research utilized textual analysis of school policies from the school communities represented in the study in addition to interview data employed in a larger systemic study from which this research is drawn. Findings contribute to a fuller understanding of the valuation process of local administrators when drafting policy in relation to an Ethic of the Profession. Practical implications include the impact of such school policies on the immediate and long-range needs of at-risk students
Phase I Trial of a Lactobacillus crispatus Vaginal Suppository for Prevention of Recurrent Urinary Tract Infection in Women
Objectives: We performed a phase I trial to assess the safety and tolerance of a Lactobacillus vaginal suppository for prevention of recurrent UTI.
Methods: Premenopausal women with a history of recurrent UTI were randomized to use L. crispatus CTV-05 or placebo vaginal suppositories daily for five days.
Results: 30 women were randomized (15 to L. crispatus CTV-05). No severe adverse events occurred. Mild to moderate vaginal discharge and genital irritation were reported by women in both study arms. Seven women randomized to L. crispatus CTV-05 developed pyuria without associated symptoms. Most women had high concentrations of vaginal
H202-producing lactobacilli before randomization. L. crispatus,
L. jensenii, and L. gasseri were the most common
Lactobacillus species identified, with stable prevalence over time.
Conclusions: L. crispatus CTV-05 can be given as a vaginal suppository with minimal sideeffects to healthy women with a history of recurrent UTI. Mild inflammation of the urinary tract was noted in some women
Edward Byrne Memorial Justice Assistance Grant (JAG) Program: Evaluation Report
The Consortium for Crime and Justice Research (CCJR) at the University of Nebraska – Omaha is conducting an evaluation of projects supported by Nebraska’s 2012 Edward Byrne Memorial Justice Assistance Grant (Byrne JAG) Program funds. The primary goal of the evaluation is to provide the Nebraska Commission on Law Enforcement and Criminal Justice (Crime Commission) a summary of the law enforcement, training, prevention, and associated activities occurring as a direct or indirect result of the infusion of Bryne JAG funds. In other words, the intent of the evaluation is to provide a summary of the funded activities and resulting products from Byrne JAG dollars. A subsidiary goal is to track the use of evidence-based practices (EBPs) supported by JAG funds. Because federal funding agencies continue to emphasize the use of practices that are supported by research evidence, we are tracking the use of EBPs, as well as fidelity to the model of the practices that have been adopted.
This report provides an overview of activities and products of funded agencies based on required performance indicator data submitted for October to December 2012 and January to March 2013. Because the funded task forces report similar data, their feedback is included in one section. In addition to the task forces, information is provided to summarize the activities of Banister’s Leadership Academy, the Nebraska Crime Commission, The Indian Center, the Law Enforcement Training Center, the Nebraska Department of Corrections, the Douglas County Attorney’s Office, and the Nebraska Attorney General’s Office
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