7,682 research outputs found
Magnetic reconnection in plasma under inertial confinement fusion conditions driven by heat flux effects in Ohm's law
In the interaction of high-power laser beams with solid density plasma there
are a number of mechanisms that generate strong magnetic fields. Such fields
subsequently inhibit or redirect electron flows, but can themselves be advected
by heat fluxes, resulting in complex interplay between thermal transport and
magnetic fields.We show that for heating by multiple laser spots reconnection
of magnetic field lines can occur, mediated by these heat fluxes, using a fully
implicit 2D Vlasov-Fokker-Planck code. Under such conditions, the reconnection
rate is dictated by heat flows rather than Alfv\`enic flows. We find that this
mechanism is only relevant in a high plasma. However, the Hall
parameter can be large so that thermal transport is
strongly modified by these magnetic fields, which can impact longer time scale
temperature homogeneity and ion dynamics in the system
The Role of Private Sector Payment Rules and a Proposed Approach for Evaluating Future Changes to Payments Law
Private sector payment organizations should continue to play the primary role in establishing rights and responsibilities for payment transactions between their participating financial institutions, provided that their rules are consistent with customer protections established by federal and state governmental authorities for the customer-financial institution relationship. Current payments law structure, relying on a combination of private sector rules, baseline statutory consumer protections, and (in the case of check payments) a somewhat variable uniform check collection statute, has shown remarkable flexibility in facilitating and responding to the unprecedented scope and pace of change that has occurred in the retail payments world over the last twenty years. The financial services industry should continue to support these two separate spheres of payment laws, private sector rules and government-mandated baseline consumer protection rules. The payment system stakeholders should not attempt to further regulate or limit, either by legislation or by regulation, the ability of private sector payment organizations to establish rules governing the relationships between their participating financial institutions
The Role of Private Sector Payment Rules and a Proposed Approach for Evaluating Future Changes to Payments Law
Private sector payment organizations should continue to play the primary role in establishing rights and responsibilities for payment transactions between their participating financial institutions, provided that their rules are consistent with customer protections established by federal and state governmental authorities for the customer-financial institution relationship. Current payments law structure, relying on a combination of private sector rules, baseline statutory consumer protections, and (in the case of check payments) a somewhat variable uniform check collection statute, has shown remarkable flexibility in facilitating and responding to the unprecedented scope and pace of change that has occurred in the retail payments world over the last twenty years. The financial services industry should continue to support these two separate spheres of payment laws, private sector rules and government-mandated baseline consumer protection rules. The payment system stakeholders should not attempt to further regulate or limit, either by legislation or by regulation, the ability of private sector payment organizations to establish rules governing the relationships between their participating financial institutions
Physicians' values and their career stage
Professional values of 241 practicing physicians were determined from factor analyzing their responses to 25 questionnaire items dealing with an ideal medical school in their vicinity. The seven factors (values)--(1) Academic, (2) Professional Separatism, (3) Support, (4) Social Welfare, (5) Research/Specialization, (6) Status/ Prestige, and (7) Convenience--were examined for their relationship to background characteristics (e.g., training) and practice (e.g., specialty). Few differences were found. However, when values were analyzed by age and career stage, significant fluctuations were found. Levinson's adult development theory was able to account for a sizeable portion of the observed variations. Practical and theoretical consequences are discussed in connection with physician stress at critical career stages.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25255/1/0000698.pd
Origin, maintenance and spread of antibiotic resistance genes within plasmids and chromosomes of bloodstream isolates of Escherichia coli
The work was funded by the Scottish Executive via the Chief Scientists Office through the provision of a grant to establish the Scottish Healthcare Associated Infection Prevention Institute (SHAIPI).Blood stream invasion by Escherichia coli is the commonest cause of bacteremia in the UK and elsewhere with an attributable mortality of about 15–20 %; antibiotic resistance to multiple agents is common in this microbe and is associated with worse outcomes. Genes conferring antimicrobial resistance, and their frequent location on horizontally transferred genetic elements is well-recognised, but the origin of these determinants, and their ability to be maintained and spread within clinically-relevant bacterial populations is unclear. Here, we set out to examine the distribution of antimicrobial resistance genes in chromosomes and plasmids of 16 bloodstream isolates of E. coli from patients within Scotland, and how these genes are maintained and spread. Using a combination of short and long-read whole genome sequencing methods, we were able to assemble complete sequences of 44 plasmids, with 16 Inc group F and 20 col plasmids; antibiotic resistance genes located almost exclusively within the F group. blaCTX-M15 genes had re-arranged in some strains into the chromosome alone (five strains), while others contained plasmid copies alone (two strains). Integrons containing multiple antibiotic genes were widespread in plasmids, notably many with a dfrA7 gene encoding resistance to trimethoprim, thus linking trimethoprim resistance to the other antibiotic resistance genes within the plasmids. This will allow even narrow spectrum antibiotics such as trimethoprim to act as a selective agent for plasmids containing antibiotic resistance genes mediating much broader resistance, including blaCTX-M15. To our knowledge, this is the first analysis to provide complete sequence data of chromosomes and plasmids in a collection of pathogenic human bloodstream isolates of E. coli. Our findings reveal the interplay between plasmids and integrative and conjugative elements in the maintenance and spread of antibiotic resistance genes within pathogenic E. coli.Publisher PDFPeer reviewe
Cost-effectiveness of rosuvastatin in comparison with generic atorvastatin and simvastatin in a Swedish population at high risk of cardiovascular events
Background: To assess the long-term cost-effectiveness of rosuvastatin therapy compared with generic simvastatin and generic atorvastatin in reducing the incidence of cardiovascular events and mortality in a Swedish population with Framingham risk ≥20%. Methods: A probabilistic Monte Carlo simulation model based on data from JUPITER (the Justification for the Use of statins in Prevention: an Intervention Trial Evaluating Rosuvastatin) was used to estimate the long-term cost-effectiveness of rosuvastatin 20 mg daily versus simvastatin or atorvastatin 40 mg for the prevention of cardiovascular death and morbidity. The three-stage model included cardiovascular event prevention simulating the 4 years of JUPITER, initial prevention beyond the trial, and subsequent cardiovascular event prevention. A Swedish health care payer perspective (direct costs only) was modeled for a lifetime horizon, with 2008/2009 as the costing period. Univariate and probabilistic sensitivity analyses were performed. Results: The incremental cost per quality-adjusted life-year (QALY) gained with rosuvastatin 20 mg over simvastatin or atorvastatin 40 mg ranged from SEK88,113 (rosuvastatin 20 mg versus simvastatin 40 mg; Framingham risk ≥30%; net avoidance of 34 events/1000 patients) to SEK497,542 (versus atorvastatin 40 mg: Framingham risk ≥20%; net avoidance of 11 events/1000 patients) over a lifetime horizon. Probabilistic sensitivity analyses indicated that at a willingness-to-pay threshold of SEK500,000/QALY, rosuvastatin 20 mg would be cost-effective for approximately 75%–85% of simulations relative to atorvastatin or simvastatin 40 mg. Sensitivity analyses indicated the findings to be robust. Conclusion: Rosuvastatin 20 mg is cost-effective over a lifetime horizon compared with generic simvastatin or atorvastatin 40 mg in patients at high cardiovascular risk in Sweden
SN 2017ein and the Possible First Identification of a Type Ic Supernova Progenitor
We have identified a progenitor candidate in archival Hubble Space Telescope
(HST) images for the Type Ic SN 2017ein in NGC 3938, pinpointing the
candidate's location via HST Target-of-Opportunity imaging of the SN itself.
This would be the first identification of a stellar-like object as a progenitor
candidate for any Type Ic supernova to date. We also present observations of SN
2017ein during the first ~49 days since explosion. We find that SN 2017ein most
resembles the well-studied Type Ic SN 2007gr. We infer that SN 2017ein
experienced a total visual extinction of A_V~1.0--1.9 mag, predominantly
because of dust within the host galaxy. Although the distance is not well
known, if this object is the progenitor, it was likely of high initial mass,
~47--48 M_sun if a single star, or ~60--80 M_sun if in a binary system.
However, we also find that the progenitor candidate could be a very blue and
young compact cluster, further implying a very massive (>65 M_sun) progenitor.
Furthermore, the actual progenitor might not be associated with the candidate
at all and could be far less massive. From the immediate stellar environment,
we find possible evidence for three different populations; if the SN progenitor
was a member of the youngest population, this would be consistent with an
initial mass of ~57 M_sun. After it has faded, the SN should be reobserved at
high spatial resolution and sensitivity, to determine whether the candidate is
indeed the progenitor.Comment: Revised, following referee's comments, and accepted to ApJ; 21 pages,
10 figure
Post-hospitalization remote monitoring for patients with heart failure or chronic obstructive pulmonary disease in an Accountable Care Organization
BACKGROUND: Post-hospitalization remote patient monitoring (RPM) has potential to improve health outcomes for high-risk patients with chronic medical conditions. The purpose of this study is to determine the extent to which RPM for patients with congestive heart failure (CHF) and chronic obstructive pulmonary disease (COPD) is associated with reductions in post-hospitalization mortality, hospital readmission, and ED visits within an Accountable Care Organization (ACO).
METHODS: Nonrandomized prospective study of patients in an ACO offered enrollment in RPM upon hospital discharge between February 2021 and December 2021. RPM comprised of vital sign monitoring equipment (blood pressure monitor, scale, pulse oximeter), tablet device with symptom tracking software and educational material, and nurse-provided oversight and triage. Expected enrollment was for at least 30-days of monitoring, and outcomes were followed for 6 months following enrollment. The co-primary outcomes were (a) the composite of death, hospital admission, or emergency care visit within 180 days of eligibility, and (b) time to occurrence of this composite. Secondary outcomes were each component individually, the composite of death or hospital admission, and outpatient office visits. Adjusted analyses involved doubly robust estimation to address confounding by indication.
RESULTS: Of 361 patients offered remote monitoring (251 with CHF and 110 with COPD), 140 elected to enroll (106 with CHF and 34 with COPD). The median duration of RPM-enrollment was 54 days (IQR 34-85). Neither the 6-month frequency of the co-primary composite outcome (59% vs 66%, FDR p-value = 0.47) nor the time to this composite (median 29 vs 38 days, FDR p-value = 0.60) differed between the groups, but 6-month mortality was lower in the RPM group (6.4% vs 17%, FDR p-value = 0.02). After adjustment for confounders, RPM enrollment was associated with nonsignificantly decreased odds for the composite outcome (adjusted OR [aOR] 0.68, 99% CI 0.25-1.34, FDR p-value 0.30) and lower 6-month mortality (aOR 0.41, 99% CI 0.00-0.86, FDR p-value 0.20).
CONCLUSIONS: RPM enrollment may be associated with improved health outcomes, including 6-month mortality, for selected patient populations
Identification of the Origin of Monojet Signatures at the LHC
Several new physics scenarios can lead to monojet signatures at the LHC. If
such events are observed above the Standard Model background it will be
important to identify their origin. In this paper we compare and contrast these
signatures as produced in two very different pictures: vector or scalar
unparticle production in the scale-invariant/conformal regime and graviton
emission in the Arkani-Hamed, Dimopoulos and Dvali extra-dimensional model. We
demonstrate that these two scenarios can be distinguished at the LHC for a
reasonable range of model parameters through the shape of their respective
monojet and/or missing distributions.Comment: 17 pages, 6 figs; figure and discussions adde
- …