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Technology status of spray calcination--vitrification of high-level liquid waste for full-scale application
Spray calcination and vitrification technology for stabilization of high-level nuclear wastes has been developed to the point that initiation of technology transfer to an industrial-sized facility could begin. This report discusses current process and equipment development status together with additional R and D studies and engineering evaluations needed. Preliminary full-scale process and equipment descriptions are presented. Technology application in a full-scale plant would blend three distinct maintenance design philosophies, depending on service life anticipated: (1) totally remote maintenance with limited viewing and handling equipment, (2) totally remote maintenance with extensive viewing and handling equipment, and (3) contact maintenance
Target structure independent elastic scattering at low momentum transfers
Analyzing powers and cross sections for the elastic scattering of polarized
7Li by targets of 6Li, 7Li and 12C are shown to depend only on the properties
of the projectile for momentum transfers of less than 1.0 fm-1. The result of a
detailed analysis of the experimental data within the framework of the coupled
channels model with ground state reorientation and transitions to the excited
states of the projectile and targets included in the coupling schemes are
presented. This work suggests that nuclear properties of weakly-bound nuclei
can be tested by elastic scattering experiments, independent of the target
used, if data are acquired for momentum transfers less than ~1.0 fm-1.Comment: 9 pages, 4 figures, 1 table, accepted in Phys. Lett.
Simultaneous Optical Model Analyses of Elastic Scattering, Breakup, and Fusion Cross Section Data for the He + Bi System at Near-Coulomb-Barrier Energies
Based on an approach recently proposed by us, simultaneous
-analyses are performed for elastic scattering, direct reaction (DR)
and fusion cross sections data for the He+Bi system at
near-Coulomb-barrier energies to determine the parameters of the polarization
potential consisting of DR and fusion parts. We show that the data are well
reproduced by the resultant potential, which also satisfies the proper
dispersion relation. A discussion is given of the nature of the threshold
anomaly seen in the potential
Wildfire selectivity for land cover type: does size matter ?
Previous research has shown that fires burn certain land cover types disproportionally to their abundance. We used quantile
regression to study land cover proneness to fire as a function of fire size, under the hypothesis that they are inversely
related, for all land cover types. Using five years of fire perimeters, we estimated conditional quantile functions for lower
(avoidance) and upper (preference) quantiles of fire selectivity for five land cover types - annual crops, evergreen oak
woodlands, eucalypt forests, pine forests and shrublands. The slope of significant regression quantiles describes the rate of
change in fire selectivity (avoidance or preference) as a function of fire size. We used Monte-Carlo methods to randomly
permutate fires in order to obtain a distribution of fire selectivity due to chance. This distribution was used to test the null
hypotheses that 1) mean fire selectivity does not differ from that obtained by randomly relocating observed fire perimeters;
2) that land cover proneness to fire does not vary with fire size. Our results show that land cover proneness to fire is higher
for shrublands and pine forests than for annual crops and evergreen oak woodlands. As fire size increases, selectivity
decreases for all land cover types tested. Moreover, the rate of change in selectivity with fire size is higher for preference
than for avoidance. Comparison between observed and randomized data led us to reject both null hypotheses tested
(a = 0.05) and to conclude it is very unlikely the observed values of fire selectivity and change in selectivity with fire size are
due to chance.Funding: This paper was supported by the Fundação para a Ciência e Tecnologia Ph.D. Grant SFRH/BD/40398/2007. JMCP participated in this research under the
framework of research projects ‘‘Forest fire under climate, social and economic changes in Europe, the Mediterranean and other fire-affected areas of the world
(FUME)’’, EC FP7 Grant Agreement No. 243888. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the
manuscrip
Shell Gap Reduction In Exotic N = 17 Nuclei
An experimental spectroscopic investigation of some neutron rich Mg and Al isotopes around the shell closure N=20 has been performed. The delayed neutron and spectra, following the -decay of Mg and Al have been measured using the delayed neutron detector array TONNERRE coupled with high efficiency EXOGAM clover detectors, a LEPS detector and eight low-energy neutron detectors. A detailed analysis of such spectra allows one to construct the level schemes of their daughters, ^{32,33)Al and Si. The resulting spectroscopic information will provide stringent tests of large scale shell model calculations including np - nh excitations aimed at the understanding of the structural effects occurring in this region
spectroscopy of Ne and Na
Expérience GANILThe spectroscopy of Ne and Na was studied from the reaction of Ne with a deuterium target in inverse kinematics at 9.7 MeV/nucleon. The selectivity of the (d,p),(d,t), and (d,n) transfer reactions provides new spectroscopic information on low-lying states. The validity of the sd shell-model space for these nuclei is discussed
Experimental evidence for subshell closure in He and indication of a resonant state in He below 1 MeV
NESTERThe spectroscopy of the unstable He and unbound He nuclei is investigated via the p(He, d) transfer reaction with a 15.7A MeV He beam from the SPIRAL facility. The emitted deuterons were detected by the telescope array MUST. The results are analyzed within the coupled-channels Born approximation framework, and a spectroscopic factor S=4.4±1.3 for neutron pickup to the He_g.s.^{8}^{7}E^*\GammaE^*$=2.9±0.1 MeV. Both are in agreement with previous separate measurements. The reproduction of the first excited state below 1 MeV would be a challenge for the most sophisticated nuclear theories
Promising insights into the health related quality of life for children with severe obesity
Background
Childhood obesity is a growing health concern known to adversely affect quality of life in children and adolescents. The Patient Reported Outcomes Measurement Information System (PROMIS) pediatric measures were developed to capture child self-reports across a variety of health conditions experienced by children and adolescents. The purpose of this study is to begin the process of validation of the PROMIS pediatric measures in children and adolescents affected by obesity.
Methods
The pediatric PROMIS instruments were administered to 138 children and adolescents in a cross-sectional study of patient reported outcomes in children aged 8–17 years with age-adjusted body mass index (BMI) greater than the 85th percentile in a design to establish known-group validity. The children completed the depressive symptoms, anxiety, anger, peer relationships, pain interference, fatigue, upper extremity, and mobility PROMIS domains utilizing a computer interface. PROMIS domains and individual items were administered in random order and included a total of 95 items. Patient responses were compared between patients with BMI 85 to < 99th percentile versus ≥ 99th percentile.
Results
136 participants were recruited and had all necessary clinical data for analysis. Of the 136 participants, 5% ended the survey early resulting in missing domain scores at the end of survey administration. In multivariate analysis, patients with BMI ≥ 99th percentile had worse scores for depressive symptoms, anger, fatigue, and mobility (p < 0.05). Parent-reported exercise was associated with better scores for depressive symptoms, anxiety, and fatigue (p < 0.05).
Conclusions
Children and adolescents ranging from overweight to severely obese can complete multiple PROMIS pediatric measures using a computer interface in the outpatient setting. In the 5% with missing domain scores, the missing scores were consistently found in the domains administered last, suggesting the length of the assessment is important. The differences in domain scores found in this study are consistent with previous reports investigating the quality of life in children and adolescents with obesity. We show that the PROMIS instrument represents a feasible and potentially valuable instrument for the future study of the effect of pediatric obesity on quality of life
Breakup of F on Pb near the Coulomb barrier
Angular distributions of oxygen produced in the breakup of F incident
on a Pb target have been measured around the grazing angle at beam
energies of 98 and 120 MeV. The data are dominated by the proton stripping
mechanism and are well reproduced by dynamical calculations. The measured
breakup cross section is approximately a factor of 3 less than that of fusion
at 98 MeV. The influence of breakup on fusion is discussed.Comment: 7 pages, 8 figure
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