1,243 research outputs found
Is it Really a Choice? How Charter Schools Without Choice May Result in Students Without a Free Appropriate Public Education
Friedel Oscillations in Relativistic Nuclear Matter
We calculate the low-momentum N-N effective potential obtained in the OBE
approximation, inside a nuclear plasma at finite temperature, as described by
the relativistic - model. We analyze the screening effects
on the attractive part of the potential in the intermediate range as density or
temperature increase. In the long range the potential shows Friedel-like
oscillations instead of the usual exponential damping. These oscillations arise
from the sharp edge of the Fermi surface and should be encountered in any
realistic model of nuclear matter.Comment: 11 pages in preprint format, typeset using REVTEX, 3 included figures
in tar, compressed, uuencoded forma
Polypharmacy and comorbidities during pregnancy in a cohort of women with migraine
Objective: To describe longitudinal patterns of medication use throughout pregnancy in women with migraine. Methods: We used the IBM MarketScan healthcare claims database in the US to create a cohort of pregnancies enrolled between 2011–2015 resulting in live or stillbirth. Migraine headache was identified based on ICD-9-CM diagnosis codes or procedure codes recorded in clinical encounters. Outcomes were patterns of prescriptions filled for medications that may be used to prevent migraine (antiepileptics, antihypertensives, antidepressants) or treat acute episodes (opioids, triptans, acetaminophen) and of other comorbid conditions (hypertension, psychiatric diagnoses, epilepsy). We used group-based multi-trajectory models to cluster women into similar longitudinal patterns of prescription fills. Results: Of 859,501 pregnancies, 8168 had migraine. Within migraineurs, before pregnancy, the most commonly filled prescription was for a triptan (43.2%), followed by opioids (26.7%), acetaminophen (26.2%), antidepressants (24.9%), antiepileptics (18.6%) and antihypertensives (12.3%). Antiepileptics, antidepressants, and triptans were frequently discontinued early in pregnancy with few new users, while antihypertensives were discontinued by some users, but continued or initiated by a minority of users late in pregnancy. Opioids and acetaminophen were used intermittently throughout pregnancy. Comorbidities included hypertension (10.8%), epilepsy (4.7%), depression (14.0%), and anxiety (15.6%). Polypharmacy involving both preventive and acute medications was most common before pregnancy (31.4%) and declined in first trimester (14.7%). In all, 25.9% of women filled prescriptions for two or more acute medications before pregnancy. Conclusions: Medication use patterns during pregnancy for women with migraine are complex. Patterns of polypharmacy and comorbidity during pregnancy highlight an under-studied area relevant for maternal and child health outcomes
Testing postcombustion CO2 capture with CaO in a 1.7 MWt pilot facility
AbstractCalcium looping, CaL, is a new and rapidly developing technology that makes use of CaO as a high temperature regenerable sorbent of CO2. Previous theoretical and lab scale studies have shown that this technology could lead to a substantial reduction in the cost of CO2 capture and energy penalties because heat can be effectively recovered from this high temperature solid looping system. We report in this paper on the first results from a pilot plant designed to demonstrate the viability of postcombustion capture of CO2 using CaL under conditions comparable to those expected in a large scale plant. The pilot includes two interconnected circulating fluidized bed reactors of 15 m height: a CO2 absorber (carbonator) able to treat up to 2400kg/h (equivalent to about 1.7 MWth), and an oxy-fired CFB calciner with a firing power between 1-3 MWth. CO2 capture efficiencies over 90% have been experimentally observed, including continuous operation with highly cycled solids in the system (i.e. with modest CO2 carrying capacities). SO2 capture is shown to be extremely high, with concentrations of SO2 well below 10 ppmv at the exit of the carbonator. Closure of carbon and sulfur balances is satisfactory. These results should be valuable base for model validation and scaling up purposes in future stages of the EU FP7 “CaOling” project, under which this investigation has been carried out
Experimental Analysis of the Multipactor Effect With RF Pulsed Signals
© 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The main goal of this letter is the analysis of the
multipactor effect within a coaxial waveguide excited by an
RF pulsed signal. The variation of the multipactor RF voltage
thresholdwiththe
ON
interval length of the pulse has been
analyzed. To reach this aim, an in-house multipactor simulation
code based on the Monte-Carlo algorithm has been implemented.
The numerical simulations show that the multipactor RF voltage
threshold increases as the
ON
pulse interval diminishes.
In addition, an experiment was carried out to validate the
proposed theoretical model, and demonstrating the excellent
agreement between the theory and the experimental data. Finally,
the results are compared with the 20-gap-crossing rule used in
the space standard document (ECSS-E20-1A).The work of O. Monerris Belda was supported by the European Regional Development Fund. The review of this letter was arranged by Editor A. Ortiz-Conde.Gonzalez Iglesias, D.; Monerris Belda, Ó.; Diaz, M.; Gimeno Martinez, B.; Boria Esbert, VE.; Raboso García-Baquero, D. (2015). Experimental Analysis of the Multipactor Effect With RF Pulsed Signals. IEEE Electron Device Letters. 36(10):1085-1087. doi:10.1109/LED.2015.2468068S10851087361
Application of the Analytic Hierarchy Process to Riparian Revegetation Policy Options
While riparian vegetation can play a major role in protecting land, water and natural habitat in catchments, there are high costs associated with tree planting and establishment and in diverting land from cropping. The distribution of costs and benefits of riparian revegetation creates conflicts in the objectives of various stakeholder groups, and elicitation of importance weights of objectives and determination of rankings of a number of policy options by these stakeholder groups becomes critical in decision-making. The analytic hierarchy process (AHP) is a multicriteria analysis technique that provides an appropriate tool to accommodate the conflicting views of various stakeholder groups. The AHP allows the users to assess the relative importance of multiple criteria (or multiple alternatives against a given criterion) in an intuitive manner. This paper presents an application of AHP to obtain preference weights of environmental, social and economic objectives which have been used in ranking riparian revegetation policy options in a small catchment (watershed) in north Queensland, Australia. The preference weights towards environmental, economic and social objectives have been obtained for the various stakeholder groups (landholders, representatives of local sugar mill staff, environmentalists, recreational fishers and the local community). The AHP technique has proved useful in eliciting objectives and ranking policy options as well as in checking for consistency of the statements of stakeholder groups. Implementation of this approach requires a complex data elicitation process
Limits on excited tau leptons masses from leptonic tau decays
We study the effects induced by excited leptons on the leptonic tau decay at
one loop level. Using a general effective lagrangian approach to describe the
couplings of the excited leptons, we compute their contributions to the
leptonic decays and use the current experimental values of the branching ratios
to put limits on the mass of excited states and the substructure scale.Comment: 10 pages, 6 figures, to be published in Phys. Rev.
Charged lepton Flavor Violation in Supersymmetry with Bilinear R-Parity Violation
The simplest unified extension of the Minimal Supersymmetric Standard Model
with bi-linear R-parity violation naturally predicts a hierarchical neutrino
mass spectrum, suitable to explain atmospheric and solar neutrino fluxes. We
study whether the individual violation of the lepton numbers L_{e,mu,tau} in
the charged sector can lead to measurable rates for BR(mu->e gamma)and
$BR(tau-> mu gamma). We find that some of the R-parity violating terms that are
compatible with the observed atmospheric neutrino oscillations could lead to
rates for mu->e gamma measurable in projected experiments. However, the Delta
m^2_{12} obtained for those parameters is too high to be compatible with the
solar neutrino data, excluding therefore the possibility of having measurable
rates for mu->e gamma in the model.Comment: 29 pages, 8 figures. Constraint from solar neutrino data included,
conclusions changed respect v
Psychiatric comorbidity in individuals with bullous pemphigoid and all bullous disorders in the Danish national registers
BACKGROUND: Bullous pemphigoid (BP) is an autoimmune blistering skin disease that takes a profound physical and mental toll on those affected. The aim of the study was to investigate the bidirectional association between BP and all bullous disorders (ABD) with a broad array of psychiatric disorders, exploring the influence of prescribed medications. METHODS: This nationwide, register-based cohort study encompassed 6,470,450 individuals born in Denmark and alive from 1994 to 2016. The hazard ratios (HRs) of a subsequent psychiatric disorder in patients with BP/ABD and the reverse exposure and outcome were evaluated. RESULTS: Several psychiatric disorders were associated with increased risk of subsequent BP (4.18-fold for intellectual disorders, 2.32-fold for substance use disorders, 2.01-fold for schizophrenia and personality disorders, 1.92-1.85-1.49-fold increased risk for organic disorders, neurotic and mood disorders), independent of psychiatric medications. The association between BP and subsequent psychiatric disorders was not significant after adjusting for BP medications, except for organic disorders (HR 1.27, CI 1.04-1.54). Similar results emerged with ABD. CONCLUSION: Psychiatric disorders increase the risk of a subsequent diagnosis of BP/ABD independent of medications, whereas medications used for the treatment of BP/ABD appear to account for the subsequent onset of psychiatric disorders. Clinically, an integrated approach attending to both dermatological and psychiatric symptoms is recommended, and dermatologists should remain vigilant for early symptoms of psychiatric disorders to decrease mental health comorbidity
Self Consistent Molecular Field Theory for Packing in Classical Liquids
Building on a quasi-chemical formulation of solution theory, this paper
proposes a self consistent molecular field theory for packing problems in
classical liquids, and tests the theoretical predictions for the excess
chemical potential of the hard sphere fluid. Results are given for the self
consistent molecular fields obtained, and for the probabilities of occupancy of
a molecular observation volume. For this system, the excess chemical potential
predicted is as accurate as the most accurate prior theories, particularly the
scaled particle (Percus-Yevick compressibility) theory. It is argued that the
present approach is particularly simple, and should provide a basis for a
molecular-scale description of more complex solutions.Comment: 6 pages and 5 figure
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