931 research outputs found
Neutron capture cross section measurements of 238U, 241Am and 243Am at n_TOF
Proposal: Neutron capture cross section measurements of 238U, 241Am and 243Am at n_TOFThe increase of the world energy demand and the need of low carbon energy sources have triggered the renaissance and/or enhancement of nuclear energy in many countries. Fundamental nuclear physics can contribute in a practical way to the sustainability and safety of the nuclear energy production and the management of the nuclear waste. There exists a series of recent studies which address the most relevant isotopes, decay data, nuclear reaction channels and energy ranges which have to be investigated in more detail for improving the design of different advanced nuclear systems [1] and nuclear fuel cycles [2]. In this proposal, we aim at the measurement of the neutron capture cross sections of 238U, 241Am and 243Am. All three isotopes are listed in the NEA High Priority Request List [37], are recommended for measurements [1] and play an important role in the nuclear energy production and fuel cycle scenarios. The measurements will provide as well valuable nuclear structure data necessary for the improvement of nuclear models and the statistical interpretation of the nuclear propertiesPostprint (author's final draft
Fm receiver, re test console, appendix i final report
Input bandpass filter, limiter, conventional and phase lock FM detector, output low pass filter, and offset frequency for FM receive
Menâs and womenâs migration in coastal Ghana
This article uses life history calendar (LHC) data from coastal Ghana and event history statistical methods to examine inter-regional migration for men and women, focusing on four specific migration types: rural-urban, rural-rural, urban-urban, and urban-rural. Our analysis is unique because it examines how key determinants of migrationĂąâŹâincluding education, employment, marital status, and childbearingĂąâŹâdiffer by sex for these four types of migration. We find that women are significantly less mobile than men overall, but that more educated women are more likely to move (particularly to urban areas) than their male counterparts. Moreover, employment in the prior year is less of a deterrent to migration among women. While childbearing has a negative effect on migration, this impact is surprisingly stronger for men than for women, perhaps because womenâs search for assistance in childcare promotes migration. Meanwhile, being married or in union appears to have little effect on migration probabilities for either men or women. These results demonstrate the benefits of a LHC approach and suggest that migration research should further examine menâs and womenâs mobility as it relates to both human capital and household and family dynamics, particularly in developing settings.event history analysis, Ghana, life history, migration, Sub-Saharan Africa, urbanization
Memory effect, conformal symmetry and gravitational plane waves
We discuss in some detail the interaction of classical particles, including
the scattering and memory effect, with a pulse of gravitational plane wave. The
key point is the conformal symmetry of gravitational plane waves. In
particular, we obtain, in the limit of short pulse, some results for impulsive
gravitational waves. Furthermore, in the general case, we give certain
conditions which allow us to completely describe the interaction in terms of
the singular Baldwin-Jeffery-Rosen coordinates.Comment: editorial corrections, references added, 19 page
Electrodynamics of the vortex lattice in untwinned YBaCuO by complex impedance measurements
We report complex impedance measurements in an untwinned YBaCuO crystal. Our
broad frequency range covers both the quasi static response and the resistive
response of the vortex lattice. It allow us to characterize the irreversibility
line without the need of any frequency dependent pinning parameters. We confirm
the validity of the two modes model of vortex dynamic, and extract both the
surface critical current and the flux flow resistivity around the first order
transition . This latter is identified by the abrupt loss of pinning and
by an unexpected step of at .Comment: accepted for publication in EPJ
The neutron time-of-flight facility n-TOF at CERN: Phase II
Neutron-induced reactions are studied at the neutron time-of-flight facility n-TOF at CERN. The facility uses 6âŒns wide pulses of 20 GeV/c protons impinging on a lead spallation target. The large neutron energy range and the high instantaneous neutron flux combined with high resolution are among the key characteristics of the facility. After a first phase of data taking during the period 2001-2004, the facility has been refurbished with an upgraded spallation target and cooling system for a second phase of data taking which started in 2009. Since 2010, the experimental area at 185 m where the neutron beam arrives, has been modified into a worksector of type A, allowing the extension of the physics program to include neutron-induced reactions on radioactive isotopes
Assimilation to the Unmarked
Steel, JC ORCiD: 0000-0003-3608-7542Intravitreal injection of recombinant adeno-associated virus (AAV) might be an alternative approach for retinal gene therapy for certain applications. Although the jelly-like substance consists mainly of water, anti-viral antibodies against various viruses such as HIV or HSV have been observed in the human vitreous and anti-AAV neutralising antibodies (NAbs) in rhesus macaque vitreous have also been detected. In this study, the human vitreous humour was obtained from 70 post mortem unpaired eye cups and 10 paired eye cups from the Queensland Eye Bank. The transduction efficiency of 1-3 · 108 vcg of recombinant AAV-2, -5, -6 and -8 expressing secreted nanoluciferase was measured following transduction of ARPE-19 and Cos-7 cells at vitreous humour dilutions from 1:2 to 1:10
000. At vitreous humour dilution of 1:2, a reduction in transduction of over 50% was observed for AAV2 in 50.5% of samples and for AAV6 in 66.2% of samples. Only 23.2% of tested samples showed similar reduction in transduction efficiency for AAV5, and for AAV8 only 2.5% of samples inhibited transduction by 50% at 1:2 dilution. Differences in serum antibody levels have been previously observed in a similar Australian population, but low transduction inhibition at vitreous humour dilutions of 1:100 suggests that the concentration of NAbs within the vitreous humour is lower than in human serum. In addition, this study also reported an increase in transduction efficiency for AAV8 at highest vitreous humour concentrations, supporting previous reports that human albumin can increase AAV transduction but only in some serotypes
First results of the new n_TOF spallation target commissioning
The Neutron Time of Flight facility n_TOF located at CERN started to take data in 2001 . Due to an increase of radioactivity released in the cooling water the experiment was stopped by end of 2004 . In 2008 a new spallation target has been installed . In 2009 the collaboration has performed the full commissioning of the facility, consisting in the determination of the fluence, the beam profile, and the energy resolution of the neutron beam. After a brief description of the new target assembly, very preliminary results concerning the shape of the neutron fluence and its absolute value will be given. Measurements of the neutron beam profile will also be shown.Postprint (published version
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