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Summary  

We have developed cleanroom compatible techniques for processing bone samples for characterization of their uranium and plutonium content. The bone samples are dried and ashed in quartz crucibles placed inside cleanroom compatible thermal ashing furnaces. The bone ash is dissolved in ultra-pure acids prepared by sub-boiling distillation. The uranium and plutonium in the samples are isolated and purified by ion-exchange chromatography and measured by thermal ionization mass spectrometry. The technique is capable of detecting 74 picograms of 238U and 8 femtograms of 239Pu in 100 mg bone ash samples. If the ash contains larger amounts of uranium and plutonium, the technique can be used to isotopically fingerprint the material to identify potential origins.

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Summary  

Extensive soil and sediment sampling was conducted along the Colorado Front Range and the plains east of the Front Range at locations believed to only be exposed to global fallout. The average 240Pu/239Pu atom ratio in the samples collected in Colorado was determined to be 0.165±0.008. A limited number of samples were collected at various locations in the Arctic at approximately 70° N latitude. Analyses of these samples predict that the 240Pu/239Pu atom ratio in environmental samples collected at 70° N latitude at locations only containing fallout is 0.183±0.009. These results provide data that help to precisely define the 240Pu/239Pu atom ratios representative of global fallout at the two locations studied.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Wagner, S. Boone, J. Chamberlin, C. Duffy, D. Efurd, K. Israel, N. Koski, D. Kottmann, D. Lewis, P. Lindahl, F. Roensch, and R. Steiner

Abstract  

Utilization of thermal ionization mass spectrometry as a routine analytical service provided to the Los Alamos National Laboratory Bioassay Program has evolved significantly since its implementation just over three years ago. Converting this unique research tool designed to support nuclear weapons testing to a quasi-production mode for the routine analysis of ~300 urine samples/year for ultra-low levels of plutonium has required resolution of numerous practical issues. These issues include clean-room sample preparation, adequate tracer recovery, customer specified turn-around times, throughput, water and urine blank values, statistical data reduction, and quality control and performance evaluation sample requirements.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. P. LaMont, T. R. LaBone, J. R. Cadieux, W. M. Findley, G. Hall, C. R. Shick, D. W. Efurd, and R. E. Steiner

Summary  

The lung dissolution rates for PuO2 were determined using a 100 day in vitro experiment. A very small amount of the PuO2 rapidly dissolved with a half-time of approximately 10 days, while the majority of the material (>99%) dissolved with a half-time of approximately 5 . 105 days. This dissolution half time is significantly longer than what is recommended by the ICRP, and would result in higher calculated doses for inhalation intakes of PuO2 than those currently estimated by the ICRP 66 human respiratory tract model for radiological protection.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: L. Tandon, E. Hastings, J. Banar, J. Barnes, D. Beddingfield, D. Decker, J. Dyke, D. Farr, J. FitzPatrick, D. Gallimore, S. Garner, R. Gritzo, T. Hahn, G. Havrilla, B. Johnson, K. Kuhn, S. LaMont, D. Langner, C. Lewis, V. Majidi, P. Martinez, R. McCabe, S. Mecklenburg, D. Mercer, S. Meyers, V. Montoya, B. Patterson, R. Pereyra, D. Porterfield, J. Poths, D. Rademacher, C. Ruggiero, D. Schwartz, M. Scott, K. Spencer, R. Steiner, R. Villarreal, H. Volz, L. Walker, A. Wong, and C. Worley

Abstract  

The goal of nuclear forensics is to establish an unambiguous link between illicitly trafficked nuclear material and its origin. The Los Alamos National Laboratory (LANL) Nuclear Materials Signatures Program has implemented a graded “conduct of operations” type analysis flow path approach for determining the key nuclear, chemical, and physical signatures needed to identify the manufacturing process, intended use, and origin of interdicted nuclear material. This analysis flow path includes both destructive and non-destructive characterization techniques and has been exercized against different nuclear materials from LANL’s special nuclear materials archive. Results obtained from the case study will be presented to highlight analytical techniques that offer the critical attribution information.

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Including gaming disorder in the ICD-11: The need to do so from a clinical and public health perspective

Commentary on: A weak scientific basis for gaming disorder: Let us err on the side of caution (van Rooij et al., 2018)

Journal of Behavioral Addictions
Authors: Hans-Jürgen Rumpf, Sophia Achab, Joël Billieux, Henrietta Bowden-Jones, Natacha Carragher, Zsolt Demetrovics, Susumu Higuchi, Daniel L. King, Karl Mann, Marc Potenza, John B. Saunders, Max Abbott, Atul Ambekar, Osman Tolga Aricak, Sawitri Assanangkornchai, Norharlina Bahar, Guilherme Borges, Matthias Brand, Elda Mei-Lo Chan, Thomas Chung, Jeff Derevensky, Ahmad El Kashef, Michael Farrell, Naomi A. Fineberg, Claudia Gandin, Douglas A. Gentile, Mark D. Griffiths, Anna E. Goudriaan, Marie Grall-Bronnec, Wei Hao, David C. Hodgins, Patrick Ip, Orsolya Király, Hae Kook Lee, Daria Kuss, Jeroen S. Lemmens, Jiang Long, Olatz Lopez-Fernandez, Satoko Mihara, Nancy M. Petry, Halley M. Pontes, Afarin Rahimi-Movaghar, Florian Rehbein, Jürgen Rehm, Emanuele Scafato, Manoi Sharma, Daniel Spritzer, Dan J. Stein, Philip Tam, Aviv Weinstein, Hans-Ulrich Wittchen, Klaus Wölfling, Daniele Zullino, and Vladimir Poznyak

The proposed introduction of gaming disorder (GD) in the 11th revision of the International Classification of Diseases (ICD-11) developed by the World Health Organization (WHO) has led to a lively debate over the past year. Besides the broad support for the decision in the academic press, a recent publication by van Rooij et al. (2018) repeated the criticism raised against the inclusion of GD in ICD-11 by Aarseth et al. (2017). We argue that this group of researchers fails to recognize the clinical and public health considerations, which support the WHO perspective. It is important to recognize a range of biases that may influence this debate; in particular, the gaming industry may wish to diminish its responsibility by claiming that GD is not a public health problem, a position which maybe supported by arguments from scholars based in media psychology, computer games research, communication science, and related disciplines. However, just as with any other disease or disorder in the ICD-11, the decision whether or not to include GD is based on clinical evidence and public health needs. Therefore, we reiterate our conclusion that including GD reflects the essence of the ICD and will facilitate treatment and prevention for those who need it.

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