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TECHNICAL BASIS DOCUMENT FOR CRITERIA AND PROCESSES FOR THE CERTIFICATION OF NON-RADIOACTIVE HAZARDOUS AND NON-HAZARDOUS WASTES
This Technical Basis Document (TBD) identifies how the values presented in the ''Criteria and Processes for the Certification of Non-Radioactive Hazardous and Non-Hazardous Wastes'' were derived. The original moratorium document (UCRL-AR-109662) applied only to hazardous wastes generated in Radioactive Materials Management Areas (RMMAs) that were destined for off-site Treatment, Storage, and Disposal Facilities (TSDFs) that did not possess a radioactive materials license. Since its inception, the original moratorium document has become the de facto free-release procedure for potentially volumetrically contaminated materials of all varieties. This was promulgated in a February 4, 1992 memo from Jyle Lytle, Deputy Assistant Secretary for Waste Management, entitled ''Update: Moratorium on Shipment of Potentially Radioactive Hazardous and Toxic Wastes''. In this memo, Ms. Lytle states, ''While the moratorium does not apply to non-hazardous/non-TSCA solid wastes and non-waste materials, the same release criteria apply''. Over the past few years, a considerable quantity of data and operating experience has been developed, which has shown the limitations of UCRL-AR-109662. The original Moratorium is out of date, and many of the organizations and procedures that it references are no longer in existence. In addition, the original document lacked sufficient detail to be used as an LLNL-wide procedure for free release, as it only addressed hazardous wastes. The original moratorium document also used highly optimistic ''action limits'', which were based on theoretically achievable minimum detectable activity (MDA) levels for various matrices. Years of operating experience has shown that these action limits are simply not achievable for certain analyses in certain matrices, either due to limitations in sample size, or underestimates of the contribution of naturally-occurring radioactive materials, resulting in the mis-characterization of samples of these matrices as radioactive, when no radioactivity was added by LLNL operations. The new moratorium document updates the organizations involved in Moratorium Declarations, specifically addresses non-hazardous waste matrices, and allows for alternative types of analysis. The new moratorium document formalizes the process of release of potentially volumetrically-contaminated waste materials from radiological controls at LLNL
Fluid Acquisition and Resupply Experiments on Space Shuttle Flights STS-53 and STS-57
The Fluid Acquisition and Resupply Experiment (FARE) program, managed by the Marshall Space Flight Center Space Propulsion Branch with Martin Marietta Civil Space and Communications as the contractor, consisted of two flights designated FARE I and FARE II. FARE I flew in December 1992 on STS-53 with a screen channel liquid acquisition device (LAD) and FARE II flew in June 1993 on STS-57 with a vane-type LAD. Thus, the FARE I and II flights represent the two basic LAD categories usually considered for in-space fluid management. Although both LAD types have been used extensively, the usefulness of the on-orbit data has been constrained by the lack of experimentation beyond predicted performance limits, including both propellant fill and expulsion. Therefore, the FARE tests were designed to obtain data that would satisfy two primary objectives: (1) Demonstrate the performance of the two types of LADs, screen channel and vane, and (2) support the anchoring of analytical models. Both flights were considered highly successful in meeting these two primary objectives
Genomic correlates of recombination rate and its variability across eight recombination maps in the western honey bee (Apis mellifera L.)
Background: Meiotic recombination has traditionally been explained based on the structural requirement to stabilize homologous chromosome pairs to ensure their proper meiotic segregation. Competing hypotheses seek to explain the emerging findings of significant heterogeneity in recombination rates within and between genomes, but intraspecific comparisons of genome-wide recombination patterns are rare. The honey bee (Apis mellifera) exhibits the highest rate of genomic recombination among multicellular animals with about five cross-over events per chromatid. Results: Here, we present a comparative analysis of recombination rates across eight genetic linkage maps of the honey bee genome to investigate which genomic sequence features are correlated with recombination rate and with its variation across the eight data sets, ranging in average marker spacing ranging from 1 Mbp to 120 kbp. Overall, we found that GC content explained best the variation in local recombination rate along chromosomes at the analyzed 100 kbp scale. In contrast, variation among the different maps was correlated to the abundance of microsatellites and several specific tri- and tetra-nucleotides. Conclusions: The combined evidence from eight medium-scale recombination maps of the honey bee genome suggests that recombination rate variation in this highly recombining genome might be due to the DNA configuration instead of distinct sequence motifs. However, more fine-scale analyses are needed. The empirical basis of eight differing genetic maps allowed for robust conclusions about the correlates of the local recombination rates and enabled the study of the relation between DNA features and variability in local recombination rates, which is particularly relevant in the honey bee genome with its exceptionally high recombination rate. © 2014 Ross et al
Sensitivity of air pollution exposure and disease burden to emission changes in China using machine learning emulation
Machine learning models can emulate chemical transport models, reducing computational costs and enabling more experimentation. We developed emulators to predict annualâmean fine particulate matter (PM(2.5)) and ozone (O(3)) concentrations and their associated chronic health impacts from changes in five major emission sectors (residential, industrial, land transport, agriculture, and power generation) in China. The emulators predicted 99.9% of the variance in PM(2.5) and O(3) concentrations. We used these emulators to estimate how emission reductions can attain air quality targets. In 2015, we estimate that PM(2.5) exposure was 47.4Â ÎŒg m(â3) and O(3) exposure was 43.8 ppb, associated with 2,189,700 (95% uncertainty interval, 95UI: 1,948,000â2,427,300) premature deaths per year, primarily from PM(2.5) exposure (98%). PM(2.5) exposure and the associated disease burden were most sensitive to industry and residential emissions. We explore the sensitivity of exposure and health to different combinations of emission reductions. The National Air Quality Target (35Â ÎŒg m(â3)) for PM(2.5) concentrations can be attained nationally with emission reductions of 72% in industrial, 57% in residential, 36% in land transport, 35% in agricultural, and 33% in power generation emissions. We show that complete removal of emissions from these five sectors does not enable the attainment of the WHO Annual Guideline (5Â ÎŒg m(â3)) due to remaining air pollution from other sources. Our work provides the first assessment of how air pollution exposure and disease burden in China varies as emissions change across these five sectors and highlights the value of emulators in air quality research
On the Particle Data Group evaluation of Psi' and chi_c Branching Ratios
I propose a new evaluation of and branching ratios
which avoids the correlations affecting the current Particle Data Group
evaluation.
These correlations explain the apparent technique-dependent discrepancies
between the available determinations of the
and under the hypotesis that the current
values of the branching ratios are
overestimated.
In the process I also noticed that Particle Data Group has not restated many
of the older measurements, when necessary, for the new value of , which significantly affects the evaluation of some
relevant and exclusive branching ratios.Comment: 13 pages. Revised version. Submitted to Phys. Rev.
Fragmentation production of doubly heavy baryons
Baryons with a single heavy quark are being studied experimentally at
present. Baryons with two units of heavy flavor will be abundantly produced not
only at future colliders, but also at existing facilities. In this paper we
study the production via heavy quark fragmentation of baryons containing two
heavy quarks at the Tevatron, the LHC, HERA, and the NLC. The production rate
is woefully small at HERA and at the NLC, but significant at and
machines. We present distributions in various kinematical variables
in addition to the integrated cross sections at hadron colliders.Comment: 13 pages, macro package epsfig needed, 6 .eps figure files in a
separate uuencoded, compressed and tarred file; complete paper available at
http://www.physics.carleton.ca/~mad/papers/paper.p
Optimal Renormalization Scale and Scheme for Exclusive Processes
We use the BLM method to fix the renormalization scale of the QCD coupling in
exclusive hadronic amplitudes such as the pion form factor and the
photon-to-pion transition form factor at large momentum transfer.
Renormalization-scheme-independent commensurate scale relations are established
which connect the hard scattering subprocess amplitudes that control exclusive
processes to other QCD observables such as the heavy quark potential and the
electron-positron annihilation cross section. The commensurate scale relation
connecting the heavy quark potential, as determined from lattice gauge theory,
to the photon-to-pion transition form factor is in excellent agreement with
data assuming that the pion distribution amplitude is
close to its asymptotic form . We also reproduce the
scaling and normalization of the data at large
momentum transfer. Because the renormalization scale is small, we argue that
the effective coupling is nearly constant, thus accounting for the nominal
scaling behavior of the data. However, the normalization of the space-like pion
form factor obtained from electroproduction experiments is
somewhat higher than that predicted by the corresponding commensurate scale
relation. This discrepancy may be due to systematic errors introduced by the
extrapolation of the electroproduction data to the
pion pole.Comment: 22 pages, Latex, 7 Latex figures. Several references added,
discussion of scale fixing revised for clarity. Final version to appear in
Phys. Rev.
Precision Measurement of the Mass Difference
We have measured the vector-pseudoscalar mass splitting , significantly more precise than the previous
world average. We minimize the systematic errors by also measuring the
vector-pseudoscalar mass difference using the radiative
decay , obtaining
. This is
then combined with our previous high-precision measurement of
, which used the decay . We also
measure the mass difference MeV, using the
decay modes of the and mesons.Comment: 18 pages uuencoded compressed postscript (process with uudecode then
gunzip). hardcopies with figures can be obtained by sending mail to:
[email protected]
Photon-Photon and Pomeron-Pomeron Processes in Peripheral Heavy Ion Collisions
We estimate the cross sections for the production of resonances, pion pairs
and a central cluster of hadrons in peripheral heavy-ion collisions through
two-photon and double-pomeron exchange, at energies that will be available at
RHIC and LHC. The effect of the impact parameter in the diffractive reactions
is introduced, and imposing the condition for realistic peripheral collisions
we verify that in the case of very heavy ions the pomeron-pomeron contribution
is indeed smaller than the electromagnetic one. However, they give a
non-negligible background in the collision of light ions. This diffractive
background will be more important at RHIC than at LHC.Comment: 22 pages, 1 Postscript figures, 4 tables, to appear in Phys. Rev.
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