369 research outputs found
Global optical potential for nucleus-nucleus systems from 50 MeV/u to 400 MeV/u
We present a new global optical potential (GOP) for nucleus-nucleus systems,
including neutron-rich and proton-rich isotopes, in the energy range of MeV/u. The GOP is derived from the microscopic folding model with the
complex -matrix interaction CEG07 and the global density presented by S{\~
a}o Paulo group. The folding model well accounts for realistic complex optical
potentials of nucleus-nucleus systems and reproduces the existing elastic
scattering data for stable heavy-ion projectiles at incident energies above 50
MeV/u. We then calculate the folding-model potentials (FMPs) for projectiles of
even-even isotopes, C, O, Ne, Mg,
Si, S, Ar, and Ca, scattered by stable
target nuclei of C, O, Si, Ca Ni, Zr,
Sn, and Pb at the incident energy of 50, 60, 70, 80, 100, 120,
140, 160, 180, 200, 250, 300, 350, and 400 MeV/u. The calculated FMP is
represented, with a sufficient accuracy, by a linear combination of 10-range
Gaussian functions. The expansion coefficients depend on the incident energy,
the projectile and target mass numbers and the projectile atomic number, while
the range parameters are taken to depend only on the projectile and target mass
numbers. The adequate mass region of the present GOP by the global density is
inspected in comparison with FMP by realistic density. The full set of the
range parameters and the coefficients for all the projectile-target
combinations at each incident energy are provided on a permanent open-access
website together with a Fortran program for calculating the microscopic-basis
GOP (MGOP) for a desired projectile nucleus by the spline interpolation over
the incident energy and the target mass number.Comment: 25 pages, 13 figure
Efeito da solarização e biofumigação, durante o outono, na incidência de murcha-bacteriana e produtividade da batata.
Electrochemical Concentration of Aqueous [18F]Fluoride into an Aprotic Solvent in a Disposable Microfluidic Cell
A missing dimension in measures of vaccination impacts
Immunological protection, acquired from either natural infection or vaccination, varies among hosts, reflecting underlying biological variation and affecting population-level protection. Owing to the nature of resistance mechanisms, distributions of susceptibility and protection entangle with pathogen dose in a way that can be decoupled by adequately representing the dose dimension. Any infectious processes must depend in some fashion on dose, and empirical evidence exists for an effect of exposure dose on the probability of transmission to mumps-vaccinated hosts [1], the case-fatality ratio of measles [2], and the probability of infection and, given infection, of symptoms in cholera [3]. Extreme distributions of vaccine protection have been termed leaky (partially protects all hosts) and all-or-nothing (totally protects a proportion of hosts) [4]. These distributions can be distinguished in vaccine field trials from the time dependence of infections [5]. Frailty mixing models have also been proposed to estimate the distribution of protection from time to event data [6], [7], although the results are not comparable across regions unless there is explicit control for baseline transmission [8]. Distributions of host susceptibility and acquired protection can be estimated from dose-response data generated under controlled experimental conditions [9]–[11] and natural settings [12], [13]. These distributions can guide research on mechanisms of protection, as well as enable model validity across the entire range of transmission intensities. We argue for a shift to a dose-dimension paradigm in infectious disease science and community health
Slow Slip Events and Time-Dependent Variations in Locking Beneath Lower Cook Inlet of the Alaska-Aleutian Subduction Zone
We identify a series of abrupt changes in GPS site velocities in Lower Cook Inlet, Alaska, in late 2004, early 2010, and late 2011. The site motions during each time period are nearly linear. The surface deformations inferred from GPS for pre-2004 and 2010–2011 are similar to each other, as are 2004–2010 and post-2011. We estimate the slip distribution on the Alaska-Aleutian subduction plate interface accounting for upper plate block rotations and interpret this toggling between two deformation patterns as caused by transient slip. We find that by allowing negative slip deficit rates (i.e., creep rates in excess of relative plate motion), the data in Lower Cook Inlet are fit significantly better during pre-2004 and 2010–2011, suggesting the occurrence of slow slip events (SSEs) there during those time periods. The earlier SSE lasted at least 9 years (observations in that area began in 1995) with Mw ~7.8. The latter SSE had almost the same area as the earlier one and a duration of ~2 years with Mw ~7.2. During 2004–2010 and post-2011, the inversions result in only positive slip deficit rates (i.e., locking) in Lower Cook Inlet. Slip rates are nearly constant during the Lower Cook Inlet SSEs, and the events start and stop abruptly. Both of these properties contrast with observations of SSEs in Upper Cook Inlet and elsewhere. The Lower Cook Inlet SSEs are consistent with previously proposed duration-magnitude scaling laws and demonstrate that slow slip events can last as long as a decade
Development of 18F-Labeled Phosphonium Compounds for Imaging Mitochondria-rich Cells by Positron Emission Tomography
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