539 research outputs found
Study of an auroral zone rocket experiment Final report
Measurement of flux and energy spectra of protons, energetic particles, hydrogen atoms, and electrons in auroral zone by Nike-Tomahawk sounding rocke
Phenomenology of Sterile Neutrinos
The indications in favor of short-baseline neutrino oscillations, which
require the existence of one or more sterile neutrinos, are reviewed. In the
framework of 3+1 neutrino mixing, which is the simplest extension of the
standard three-neutrino mixing which can partially explain the data, there is a
strong tension in the interpretation of the data, mainly due to an
incompatibility of the results of appearance and disappearance experiments. In
the framework of 3+2 neutrino mixing, CP violation in short-baseline
experiments can explain the difference between MiniBooNE neutrino and
antineutrino data, but the tension between the data of appearance and
disappearance experiments persists because the short-baseline disappearance of
electron antineutrinos and muon neutrinos compatible with the LSND and
MiniBooNE antineutrino appearance signal has not been observed.Comment: 8 pages. Invited paper to NUFACT 11, XIIIth International Workshop on
Neutrino Factories, Super beams and Beta beams, 1-6 August 2011, CERN and
University of Geneva (Submitted to IOP conference series
A Comparison of Three Different Warm-Ups on 800-Meter Running Performance in Elite Division I Track Athletes – A Pilot Study
International Journal of Exercise Science 14(6): 1400-1407, 2021. Track and Field athletes perform different types of warm-ups at varying levels of volume and/or intensity prior to competition. Theoretically, this prepares sport specific muscles for activity by increasing muscle temperature, thus mitigating the chance for injury. There is a paucity of information regarding the optimum level for warm-ups regarding maximizing performance in middle distance events. The aim of this study was to examine the effects of three different warm-ups on 800-meter performance. Thirteen Division I student-athletes (seven males and six females) from the Southeastern Conference (SEC) who were middle distance runners participated in this study. We utilized a randomized, cross-over study design to test low, medium, and high-volume warm-up protocols on 800-meter performance. Trials were conducted over a span of three weeks on a SEC University outdoor track. We used a 2 (Sex) x 3 (Warm-Up Protocol) mixed-factor ANOVA, and our results show a main effect of warm-up volume that is not moderated by sex. Post-hoc tests reveal a high-volume warm-up yields superior results for the 800-meter run in comparison to a medium volume warm-up, which provides better results than a low-volume warm-up. These findings may be of value in providing information in program design for coaches on the most effective warm-up protocols for 800-meter runners. Identifying the best warm-up protocol to prime an 800-meter runner for peak performance may not only assist in preventing injury, but enhance performance thus leading to an increased of achievement, and confidence in personal ability
A phase Ib/II study of cabozantinib (XL184) with or without erlotinib in patients with non-small cell lung cancer.
PurposeCabozantinib is a multi-kinase inhibitor that targets MET, AXL, and VEGFR2, and may synergize with EGFR inhibition in NSCLC. Cabozantinib was assessed alone or in combination with erlotinib in patients with progressive NSCLC and EGFR mutations who had previously received erlotinib.MethodsThis was a phase Ib/II study (NCT00596648). The primary objectives of phase I were to assess the safety, pharmacokinetics, and pharmacodynamics and to determine maximum tolerated dose (MTD) of cabozantinib plus erlotinib in patients who failed prior erlotinib treatment. In phase II, patients with prior response or stable disease with erlotinib who progressed were randomized to single-agent cabozantinib 100 mg qd vs cabozantinib 100 mg qd and erlotinib 50 mg qd (phase I MTD), with a primary objective of estimating objective response rate (ORR).ResultsSixty-four patients were treated in phase I. Doses of 100 mg cabozantinib plus 50 mg erlotinib, or 40 mg cabozantinib plus 150 mg erlotinib were determined to be MTDs. Diarrhea was the most frequent dose-limiting toxicity and the most frequent AE (87.5% of patients). The ORR for phase I was 8.2% (90% CI 3.3-16.5). In phase II, one patient in the cabozantinib arm (N = 15) experienced a partial response, for an ORR of 6.7% (90% CI 0.3-27.9), with no responses for cabozantinib plus erlotinib (N = 13). There was no evidence that co-administration of cabozantinib markedly altered erlotinib pharmacokinetics or vice versa.ConclusionsDespite responses with cabozantinib/erlotinib in phase I, there were no responses in the combination arm of phase II in patients with acquired resistance to erlotinib. Cabozantinib did not appear to re-sensitize these patients to erlotinib
An exact analytical solution for generalized growth models driven by a Markovian dichotomic noise
Logistic growth models are recurrent in biology, epidemiology, market models,
and neural and social networks. They find important applications in many other
fields including laser modelling. In numerous realistic cases the growth rate
undergoes stochastic fluctuations and we consider a growth model with a
stochastic growth rate modelled via an asymmetric Markovian dichotomic noise.
We find an exact analytical solution for the probability distribution providing
a powerful tool with applications ranging from biology to astrophysics and
laser physics
Linear systems with adiabatic fluctuations
We consider a dynamical system subjected to weak but adiabatically slow
fluctuations of external origin. Based on the ``adiabatic following''
approximation we carry out an expansion in \alpha/|\mu|, where \alpha is the
strength of fluctuations and 1/|\mu| refers to the time scale of evolution of
the unperturbed system to obtain a linear differential equation for the average
solution. The theory is applied to the problems of a damped harmonic oscillator
and diffusion in a turbulent fluid. The result is the realization of
`renormalized' diffusion constant or damping constant for the respective
problems. The applicability of the method has been critically analyzed.Comment: Plain Latex, no figure, 21 page
Random paths and current fluctuations in nonequilibrium statistical mechanics
An overview is given of recent advances in nonequilibrium statistical
mechanics about the statistics of random paths and current fluctuations.
Although statistics is carried out in space for equilibrium statistical
mechanics, statistics is considered in time or spacetime for nonequilibrium
systems. In this approach, relationships have been established between
nonequilibrium properties such as the transport coefficients, the thermodynamic
entropy production, or the affinities, and quantities characterizing the
microscopic Hamiltonian dynamics and the chaos or fluctuations it may generate.
This overview presents results for classical systems in the escape-rate
formalism, stochastic processes, and open quantum systems
Characterization of a periodically driven chaotic dynamical system
We discuss how to characterize the behavior of a chaotic dynamical system
depending on a parameter that varies periodically in time. In particular, we
study the predictability time, the correlations and the mean responses, by
defining a local--in--time version of these quantities. In systems where the
time scale related to the time periodic variation of the parameter is much
larger than the ``internal'' time scale, one has that the local quantities
strongly depend on the phase of the cycle. In this case, the standard global
quantities can give misleading information.Comment: 15 pages, Revtex 2.0, 8 figures, included. All files packed with
uufile
Measured quantum probability distribution functions for Brownian motion
The quantum analog of the joint probability distributions describing a
classical stochastic process is introduced. A prescription is given for
constructing the quantum distribution associated with a sequence of
measurements. For the case of quantum Brownian motion this prescription is
illustrated with a number of explicit examples. In particular it is shown how
the prescription can be extended in the form of a general formula for the
Wigner function of a Brownian particle entangled with a heat bath.Comment: Phys. Rev. A, in pres
The influence of charge detection on counting statistics
We consider the counting statistics of electron transport through a double
quantum dot with special emphasis on the dephasing induced by a nearby charge
detector. The double dot is embedded in a dissipative enviroment, and the
presence of electrons on the double dot is detected with a nearby quantum point
contact. Charge transport through the double dot is governed by a non-Markovian
generalized master equation. We describe how the cumulants of the current can
be obtained for such problems, and investigate the difference between the
dephasing mechanisms induced by the quantum point contact and the coupling to
the external heat bath. Finally, we consider various open questions of
relevance to future research.Comment: 15 pages, 2 figures, Contribution to 5-th International Conference on
Unsolved Problems on Noise, Lyon, France, June 2-6, 200
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