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.; Pallás 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., Daròs, J.-A., & Hernández, 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., AMBRÓS, S., HERNÁNDEZ, 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/b978-0-12-801498-1.00031-0Daròs, 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). Structure–function analysis of the ribozymes of chrysanthemum chlorotic mottle viroid: a loop–loop 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

Poor nutritional status is associated with other geriatric domain impairments and adverse postoperative outcomes in onco-geriatric surgical patients – 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 ≥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 ratio’s (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

What do cyclists need to see to avoid single-bicycle crashes?

The number of single-bicycle crash victims is substantial in countries with high levels of cycling. To study the role of visual characteristics of the infrastructure, such as pavement markings, in single-bicycle crashes, a study in two steps was conducted. In Study 1, a questionnaire study was conducted among bicycle crash victims (n = 734). Logistic regression was used to study the relationship between the crashes and age, light condition, alcohol use, gaze direction and familiarity with the crash scene. In Study 2, the image degrading and edge detection method (IDED-method) was used to investigate the visual characteristics of 21 of the crash scenes. The results of the studies indicate that crashes, in which the cyclist collided with a bollard or road narrowing or rode off the road, were related to the visual characteristics of bicycle facilities. Edge markings, especially in curves of bicycle tracks, and improved conspicuity of bollards are recommended. Statement of Relevance: Elevated single-bicycle crash numbers are common in countries with high levels of cycling. No research has been conducted on what cyclists need to see to avoid this type of crash. The IDED-method to investigate crash scenes is new and proves to be a powerful tool to quantify 'visual accessibility'. © 2011 Taylor & Francis