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Oxygen sparging of residue salts
Oxygen sparge is a process for treating salt residues at Los Alamos National Laboratory by sparging oxygen through molten salts. Oxygen reacts with the plutonium trichloride in these salts to form plutonium dioxide. There is further reaction of the plutonium dioxide with plutonium metal and the molten salt to form plutonium oxychloride. Both of the oxide plutonium species are insoluble in the salt and collect atthe bottom of the crucible. This results in a decrease of a factor of 2--3 in the amount of salt that must be treated, and the amount of waste generated by aqueous treatment methods
ICTV Virus Taxonomy Profile: Avsunviroidae
[EN] Members of the family Avsunviroidae have a single-stranded circular RNA genome that adopts a rod-like or branched conformation and can form, in the strands of either polarity, hammerhead ribozymes involved in their replication in plastids through a symmetrical RNA-RNA rolling-circle mechanism. These viroids lack the central conserved region typical of members of the family Pospiviroidae. The family Avsunviroidae includes three genera, Avsunviroid, Pelamoviroid and Elaviroid, with a total of four species. This is a summary of the ICTV Report on the taxonomy of the family Avsunviroidae, which is available at /http:/www.ictv.global/report/avsunvirodae.Production of this summary, the online chapter and associated resources was funded by a grant from the Wellcome Trust (WT108418AIA).Di Serio, F.; Li, S.; Matousek, J.; Owens, R.; PallĂĄs Benet, V.; Randles, J.; Sano, T.... (2018). ICTV Virus Taxonomy Profile: Avsunviroidae. Journal of General Virology. 99(5):611-612. https://doi.org/10.1099/jgv.0.001045S611612995Flores, R., DarĂČs, J.-A., & HernĂĄndez, C. (2000). Avsunviroidae family: Viroids containing hammerhead ribozymes. Advances in Virus Research, 271-323. doi:10.1016/s0065-3527(00)55006-4Hutchins, C. J., Rathjen, P. D., Forster, A. C., & Symons, R. H. (1986). Self-cleavage of plus and minus RNA transcripts of avocado sunblotch viroid. Nucleic Acids Research, 14(9), 3627-3640. doi:10.1093/nar/14.9.3627Kuhn, D. N., Geering, A. D. W., & Dixon, J. (2017). Avocado Sunblotch Viroid. Viroids and Satellites, 297-305. doi:10.1016/b978-0-12-801498-1.00028-0FLORES, R., DELGADO, S., RODIO, M.-E., AMBRĂS, S., HERNĂNDEZ, C., & SERIO, F. D. (2006). Peach latent mosaic viroid: not so latent. Molecular Plant Pathology, 7(4), 209-221. doi:10.1111/j.1364-3703.2006.00332.xFlores, R., Gago-Zachert, S., Serra, P., De la Peña, M., & Navarro, B. (2017). Chrysanthemum Chlorotic Mottle Viroid. Viroids and Satellites, 331-338. doi:10.1016/b978-0-12-801498-1.00031-0DarĂČs, J.-A. (2016). Eggplant latent viroid: a friendly experimental system in the familyAvsunviroidae. Molecular Plant Pathology, 17(8), 1170-1177. doi:10.1111/mpp.12358Dufour, D., de la Peña, M., Gago, S., Flores, R., & Gallego, J. (2008). Structureâfunction analysis of the ribozymes of chrysanthemum chlorotic mottle viroid: a loopâloop interaction motif conserved in most natural hammerheads. Nucleic Acids Research, 37(2), 368-381. doi:10.1093/nar/gkn91
Novel Collective Effects in Integrated Photonics
Superradiance, the enhanced collective emission of energy from a coherent
ensemble of quantum systems, has been typically studied in atomic ensembles. In
this work we study theoretically the enhanced emission of energy from coherent
ensembles of harmonic oscillators. We show that it should be possible to
observe harmonic oscillator superradiance for the first time in waveguide
arrays in integrated photonics. Furthermore, we describe how pairwise
correlations within the ensemble can be measured with this architecture. These
pairwise correlations are an integral part of the phenomenon of superradiance
and have never been observed in experiments to date.Comment: 7 pages, 3 figure
Reconstructing the 3-D Trajectories of CMEs in the Inner Heliosphere
A method for the full three-dimensional (3-D) reconstruction of the
trajectories of coronal mass ejections (CMEs) using Solar TErrestrial RElations
Observatory (STEREO) data is presented. Four CMEs that were simultaneously
observed by the inner and outer coronagraphs (COR1 and 2) of the Ahead and
Behind STEREO satellites were analysed. These observations were used to derive
CME trajectories in 3-D out to ~15Rsun. The reconstructions using COR1/2 data
support a radial propagation model. Assuming pseudo-radial propagation at large
distances from the Sun (15-240Rsun), the CME positions were extrapolated into
the Heliospheric Imager (HI) field-of-view. We estimated the CME velocities in
the different fields-of-view. It was found that CMEs slower than the solar wind
were accelerated, while CMEs faster than the solar wind were decelerated, with
both tending to the solar wind velocity.Comment: 17 pages, 10 figures, 1 appendi
General distress, hopelessness-suicidal ideation and worrying in adolescence:concurrent and predictive validity of a symptom-level bifactor model for clinical diagnoses
BACKGROUND:
Clinical disorders often share common symptoms and aetiological factors. Bifactor models acknowledge the role of an underlying general distress component and more specific sub-domains of psychopathology which specify the unique components of disorders over and above a general factor.
METHODS:
A bifactor model jointly calibrated data on subjective distress from The Mood and Feelings Questionnaire and the Revised Children's Manifest Anxiety Scale. The bifactor model encompassed a general distress factor, and specific factors for (a) hopelessness-suicidal ideation, (b) generalised worrying and (c) restlessness-fatigue at age 14 which were related to lifetime clinical diagnoses established by interviews at ages 14 (concurrent validity) and current diagnoses at 17 years (predictive validity) in a British population sample of 1159 adolescents.
RESULTS:
Diagnostic interviews confirmed the validity of a symptom-level bifactor model. The underlying general distress factor was a powerful but non-specific predictor of affective, anxiety and behaviour disorders. The specific factors for hopelessness-suicidal ideation and generalised worrying contributed to predictive specificity. Hopelessness-suicidal ideation predicted concurrent and future affective disorder; generalised worrying predicted concurrent and future anxiety, specifically concurrent generalised anxiety disorders. Generalised worrying was negatively associated with behaviour disorders.
LIMITATIONS:
The analyses of gender differences and the prediction of specific disorders was limited due to a low frequency of disorders other than depression.
CONCLUSIONS:
The bifactor model was able to differentiate concurrent and predict future clinical diagnoses. This can inform the development of targeted as well as non-specific interventions for prevention and treatment of different disorders
Origins of the Ambient Solar Wind: Implications for Space Weather
The Sun's outer atmosphere is heated to temperatures of millions of degrees,
and solar plasma flows out into interplanetary space at supersonic speeds. This
paper reviews our current understanding of these interrelated problems: coronal
heating and the acceleration of the ambient solar wind. We also discuss where
the community stands in its ability to forecast how variations in the solar
wind (i.e., fast and slow wind streams) impact the Earth. Although the last few
decades have seen significant progress in observations and modeling, we still
do not have a complete understanding of the relevant physical processes, nor do
we have a quantitatively precise census of which coronal structures contribute
to specific types of solar wind. Fast streams are known to be connected to the
central regions of large coronal holes. Slow streams, however, appear to come
from a wide range of sources, including streamers, pseudostreamers, coronal
loops, active regions, and coronal hole boundaries. Complicating our
understanding even more is the fact that processes such as turbulence,
stream-stream interactions, and Coulomb collisions can make it difficult to
unambiguously map a parcel measured at 1 AU back down to its coronal source. We
also review recent progress -- in theoretical modeling, observational data
analysis, and forecasting techniques that sit at the interface between data and
theory -- that gives us hope that the above problems are indeed solvable.Comment: Accepted for publication in Space Science Reviews. Special issue
connected with a 2016 ISSI workshop on "The Scientific Foundations of Space
Weather." 44 pages, 9 figure
Solum depth spatial prediction comparing conventional with knowledge-based digital soil mapping approaches
Solum depth and its spatial distribution play an important role in different types of environmental studies. Several approaches have been used for fitting quantitative relationships between soil properties and their environment in order to predict them spatially. This work aimed to present the steps required for solum depth spatial prediction from knowledge-based digital soil mapping, comparing the prediction to the conventional soil mapping approach through field validation, in a watershed located at Mantiqueira Range region, in the state of Minas Gerais, Brazil. Conventional soil mapping had aerial photo-interpretation as a basis. The knowledge-based digital soil mapping applied fuzzy logic and similarity vectors in an expert system. The knowledge-based digital soil mapping approach showed the advantages over the conventional soil mapping approach by applying the field expert-knowledge in order to enhance the quality of final results, predicting solum depth with suited accuracy in a continuous way, making the soil-landscape relationship explicit
Poor nutritional status is associated with other geriatric domain impairments and adverse postoperative outcomes in onco-geriatric surgical patients â a multicentre cohort study
Background: Nutritional status (NS), though frequently affected in onco-geriatric patients, is no standard
part of a geriatric assessment. The aim of this study was to analyse the association between a preoperatively
impaired NS and geriatric domain impairments and adverse postoperative outcomes in onco-geriatric surgical patients.
Methods: 309 patients â„70 years undergoing surgery for solid tumours were prospectively recruited. Nine screening tools were preoperatively administered as part of a geriatric assessment. NS was based on BMI, weight loss and food intake. Odds ratioâs (OR) and 95% confidence intervals (95%CI) were estimated using logistic regression analysis. The occurrence of 30-day adverse postoperative outcomes was recorded.
Results: At a median age of 76 years, 107 patients (34.6%) had an impaired NS. Decreased performance
status and depression were associated with an impaired NS, when adjusted for tumour characteristics and comorbidities (ORPS>1 3.46; 95%CI 1.56-7.67. ORGDS>5 2.11; 95%CI 1.05-4.26). An impaired NS was an independent predictor for major complications (OR 3.3; 95%CI 1.6-6.8). Ten out of 11 patients who deceased had an impaired NS.
Conclusion: An impaired NS is prevalent in onco-geriatric patients considered to be fit for surgery. It is associated with decreased performance status and depression. An impaired NS is a predictor for adverse postoperative outcomes. NS should be incorporated in a geriatric assessment
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