3,304 research outputs found
Nonparametric Regression using the Concept of Minimum Energy
It has recently been shown that an unbinned distance-based statistic, the
energy, can be used to construct an extremely powerful nonparametric
multivariate two sample goodness-of-fit test. An extension to this method that
makes it possible to perform nonparametric regression using multiple
multivariate data sets is presented in this paper. The technique, which is
based on the concept of minimizing the energy of the system, permits
determination of parameters of interest without the need for parametric
expressions of the parent distributions of the data sets. The application and
performance of this new method is discussed in the context of some simple
example analyses.Comment: 10 pages, 4 figure
High efficiency thermionic converter studies
Research in thermionic energy conversion technology is reported. The objectives were to produce converters suitable for use in out of core space reactors, radioisotope generators, and solar satellites. The development of emitter electrodes that operate at low cesium pressure, stable low work function collector electrodes, and more efficient means of space charge neutralization were investigated to improve thermionic converter performance. Potential improvements in collector properties were noted with evaporated thin film barium oxide coatings. Experiments with cesium carbonate suggest this substance may provide optimum combinations of cesium and oxygen for thermionic conversion
New Source of CP violation in B physics ?
In this talk we discuss how the down type left-right squark mixing in
Supersymmetry can induce a new source of CP violation in the time dependent
asymmtries in B --> phi K process. We use QCD improved factorization process to
calculate the hadronic matrix element for the process and find the allowed
parameter space for and , the magnitude and phase of the down
type LR(RL) squark mixing parameter . In the same allowed
regin we calculate the expected CP asymmtries in the
process.Comment: 16 pages, Latex, 2 postscript figures, invited talk presented by N.G.
Deshpande at the 9th Adriatic meeting, Dubrovnik, Croatia, 4-14 September,
2003. With updated reference
Binary systems of neutral mesons in Quantum Field Theory
Quasi-degenerate binary systems of neutral mesons of the kaon type are
investigated in Quantum Field Theory (QFT). General constraints cast by
analyticity and discrete symmetries P, C, CP, TCP on the propagator (and on its
spectral function) are deduced. Its poles are the physical masses; this
unambiguously defines the propagating eigenstates. It is diagonalized and its
spectrum thoroughly investigated. The role of ``spurious'' states, of zero norm
at the poles, is emphasized, in particular for unitarity and for the
realization of TCP symmetry. The K_L-K_S mass splitting triggers a tiny
difference between their CP violating parameters \epsilon_L and \epsilon_S,
without any violation of TCP. A constant mass matrix like used in Quantum
Mechanics (QM) can only be introduced in a linear approximation to the inverse
propagator, which respects its analyticity and positivity properties; it is
however unable to faithfully describe all features of neutral mesons as we
determine them in QFT, nor to provide any sensible parameterization of eventual
effects of TCP violation. The suitable way to diagonalize the propagator makes
use of a bi-orthogonal basis; it is inequivalent to a bi-unitary transformation
(unless the propagator is normal, which cannot occur here). Problems linked
with the existence of different ``in'' and ``out'' eigenstates are smoothed
out. We study phenomenological consequences of the differences between the QFT
and QM treatments. The non-vanishing of semi-leptonic asymmetry \delta_S -
\delta_L does not signal, unlike usually claimed, TCP violation, while A_TCP
keeps vanishing when TCP is realized. We provide expressions invariant by the
rephasing of K0 and K0bar.Comment: 44 pages, 2 figures. Version to appear in Int. J. Mod. Phys.
Health economic evaluation of rivaroxaban in the treatment of patients with chronic coronary artery disease or peripheral artery disease
AIMS: In the COMPASS trial, rivaroxaban 2.5âmg twice daily (bid) plus acetylsalicylic acid (ASA) 100âmg once daily (od) performed better than ASA 100âmg od alone in reducing the rate of cardiovascular disease, stroke, or myocardial infarction (MI) in patients with coronary artery disease (CAD) and peripheral artery disease (PAD). A Markov model was developed to assess the cost-effectiveness of rivaroxaban plus ASA vs. ASA alone over a lifetime horizon, from the UK National Health System perspective. METHODS AND RESULTS: The base case analysis assumed that patients entered the model in the event-free health state, with the possibility to experience â€2 events, transitioning every three-month cycle, through acute and post-acute health states of MI, ischaemic stroke (IS), or intracranial haemorrhage (ICH), and death. Costs, quality-adjusted life-years (QALYs), life years-all discounted at 3.5%-and incremental cost-effectiveness ratios (ICERs) were calculated. Deterministic and probabilistic sensitivity analyses were conducted, as well as scenario analyses. In the model, patients on rivaroxaban plus ASA lived for an average of 14.0âyears with no IS/MI/ICH, and gained 9.7 QALYs at a cost of ÂŁ13 947, while those receiving ASA alone lived for an average of 12.7âyears and gained 9.3 QALYs at a cost of ÂŁ8126. The ICER was ÂŁ16 360 per QALY. This treatment was cost-effective in 98% of 5000 iterations at a willingness-to-pay threshold of ÂŁ30 000 per QALY. CONCLUSION: This Markov model suggests that rivaroxaban 2.5âmg bid plus ASA is a cost-effective alternative to ASA alone in patients with chronic CAD or PAD
Intensity modulated radiation therapy (IMRT): differences in target volumes and improvement in clinically relevant doses to small bowel in rectal carcinoma
Filling the Knowledge-to-Action Gap with Open Access Pedagogy: An Alternative Assignment Model
Knowledge translation (KT) is key to the scientific process, yet academic work produced often does not reach the public. In this article a unique undergraduate KT term assignment is presented where students summarize a large body of research into an artifact for public use. This assignment model may increase student engagement and learning outcomes while filling the knowledge-to-action translation gap. The option dovetails studentsâ and employersâ need for demonstrative performance prior to hiring, the academic push for publicly and freely available scientific knowledge (e.g., open access), and challenges involved with engagement with advanced material in both in-person and remote environments. The assignment is presented in the context of benefitting effective KT and enhancing open access to information; it is then analyzed using the American Psychological Associationâs (APA) goals for undergraduates alongside Bloomâs Taxonomy of Learning. Various APA goals accomplished through the assignment, benefits, limitations, and future directions are highlighted
The remittances behaviour of the second generation in Europe: altruism or self-interest?
Whereas most research on remittances focuses on first-generation migrants, the aim of this paper is to investigate the remitting behaviour of the host country-born children of migrants - the second generation - in various European cities. Some important studies found that migrant transnationalism is not only a phenomenon for the first generation, but
also apply to the second and higher generations, through, among other things, family visits, elder care, and remittances. At the same time, the maintenance of a strong ethnic identity in the âhostâ society does not necessarily mean that second-generation migrants have strong transnational ties to their âhomeâ country.
The data used in this paper is from âThe Integration of the European Second Generationâ (TIES) project. The survey collected information on approximately 6,250 individuals aged 18-35 with at least one migrant parent from Morocco, Turkey or former Yugoslavia, in 15 European cities, regrouped in 8 âcountriesâ. For the purpose of this paper, only
analyses for Austria (Linz and Vienna); Switzerland (Basle and Zurich); Germany (Berlin and Frankfurt); France (Paris and Strasbourg); the Netherlands (Amsterdam and Rotterdam); Spain (Barcelona and Madrid); and Sweden (Stockholm) will be presented.
Hadronic decays of eta and eta-prime with coupled channels
The hadronic decays eta -> pi pi pi, eta-prime -> pi pi pi and eta-prime ->
eta pi pi are investigated within a U(3) chiral unitary approach. Final state
interactions are included by deriving the effective s-wave potentials for meson
meson scattering from the chiral effective Lagrangian and iterating them in a
Bethe-Salpeter equation. With only a small set of parameters we are able to
explain both rates and spectral shapes of these decays.Comment: 23 page
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