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Abstract  

Capillary electrophoresis (CE) is a useful method for rapid separations of metal cations. Under ideal conditions, CE can provide complete separation of the trivalent lanthanides in less than 10 min. Simple organic ligands must be included in the electrolyte matrix to achieve good resolution between the cations. In this paper, we demonstrate how to use complexation constants from the literature to design separation protocols for the trivalent f-elements.

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Abstract  

The simultaneous determination of multiple actinide isotopes in samples where total quantity is limited can sometimes present a unique challenge for radioanalytical chemists. In this study, re-determination of 238Pu, 239+240Pu, and 241Am for soils collected and analyzed approximately three decades ago was the goal, along with direct determination of 241Pu. The soils had been collected in the early 1970’s from a shallow land burial site for radioactive wastes called the Subsurface Disposal Area (SDA) at the Idaho National Lab (INL), analyzed for 238Pu, 239+240Pu, and 241Am, and any remaining soils after analysis had been archived and stored. We designed an approach to reanalyze the 238Pu, 239+240Pu, and 241Am and determine for the first time 241Pu using a combination of traditional and new radioanalytical methodologies. The methods used are described, along with estimates of the limits of detection for gamma-and alpha-spectrometry, and liquid scintillation counting. Comparison of our results to the earlier work documents the ingrowth of 241Am from 241Pu, and demonstrates that the total amount of 241Am activity in these soil samples is greater than would be expected due to ingrowth from 241Pu decay.

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Journal of Thermal Analysis and Calorimetry
Authors: V. Budarin, J. Clark, A. Gorlova, N. Boldyreva, and V. Yatsimirsky

Abstract  

Mesoporous activated carbons and silica gel (Kieselgel 100, Merck) were modified as follows: (i) treatment with vinyltrimethoxysilane; or (ii)chlorination with CCl4 followed by the reaction with a Grignard reagent. Modification of silica gel was proved by methods FTIR, NMR-13C and element analysis on carbon. The chemical modification of coals by alkans and olefins was supported by comparison of results of thermogravimetry for modified coals and modified silica gels. Polymerization of vinyl groups on carbon surface is shown by methods thermogravimetric analysis and differential scanning calorimetry.

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Abstract  

A convenient method for introducing desired trace elements into a silica matrix is described in order to have an ideal standard for instrumental neutron activation analysis.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Horlock, J. Clark, I. Goodier, J. Barnes, G. Bentley, P. Grant, and H. O’Brien

Abstract  

82Sr has now been produced by the spallation of Molybdenum by protons of up to 800 MeV. The radiochemical recovery of strontium is described together with a description of the analytical techniques used to estimate recovered yields of the various radionuclides generated. A radionuclide generator is described for the rapid recovery of82Rb, the 1.25 min half-life decay product of82Sr. An outline is given of the quality control procedure adopted to ensure that the82Rb is suitable for clinical use.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Zeisler, S. B. Clark, S. J. Parry, G. R. Choppin, S. B. Clark, P. R. Danesi, S. J. Parry, M. Rossbach, C. Williamson, Zhifang Chai, R. Zeisler, S. J. Parry, and S. F. Heller- Zeisler

Summary  

Since the 1970's, concern about the training of radiochemists in the US has been increasing along with the age of nuclear work force, while the number of academic institutions offering undergraduate courses and the number of radiochemistry faculty has been steadily decreasing. To address this problem, a summer program has been offered through the American Chemical Society to undergraduates since 1984. Students compete nationally for this opportunity, and those selected receive a 3,000 stipend. In addition, all other expenses are paid. In this manuscript, the curriculum is described, along with the need for additional training programs and their impact.

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Journal of Behavioral Addictions
Authors: Eve H. Limbrick-Oldfield, Mariya V. Cherkasova, Dawn Kennedy, Caylee-Britt Goshko, Dale Griffin, Jason J.S. Barton, and Luke Clark

Abstract

Background and aims

Individuals with gambling disorder display increased levels of risk-taking, but it is not known if it is associated with an altered subjective valuation of gains and/or losses, perception of their probabilities, or integration of these sources of information into expected value.

Methods

Participants with gambling disorder (n = 48) were compared with a healthy comparison group (n = 35) on a two-choice lottery task that involved either gains-only or losses-only gambles. On each trial, two lotteries were displayed, showing the associated probability and magnitude of the possible outcome for each. On each trial, participants chose one of the two lotteries, and the outcome was revealed.

Results

Choice behaviour was highly sensitive to the expected value of the two gambles in both the gain and loss domains. This sensitivity to expected value was attenuated in the group with gambling disorder. The group with gambling disorder used both probability and magnitude information less, and this impairment was greater for probability information. By contrast, they used prior feedback (win vs loss) to inform their next choice, despite the independence of each trial. Within the gambling disorder group, problem gambling severity and trait gambling-related cognitions independently predicted reduced sensitivity to expected value. The majority of observed effects were consistent across both gain and loss domains.

Discussion and Conclusions

Our results provide a thorough characterization of decision processes in gain and loss domains in gambling disorder, and place these problems in the context of theoretical constructs from behavioural economics.

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Journal of Behavioral Addictions
Authors: Margo Hilbrecht, David Baxter, Max Abbott, Per Binde, Luke Clark, David C. Hodgins, Darrel Manitowabi, Lena Quilty, Jessika SpÅngberg, Rachel Volberg, Douglas Walker, and Robert J. Williams

Abstract

Background and aims

The Conceptual Framework of Harmful Gambling moves beyond a symptoms-based view of harm and addresses a broad set of factors related to the risks and effects of gambling harmfully at the individual, family, and community levels. Coauthored by international research experts and informed by multiple stakeholders, Gambling Research Exchange (GREO) facilitated the framework development in 2013 and retains responsibility for regular updates and mobilization. This review article presents information about the revised version of the Conceptual Framework of Harmful Gambling completed in late 2018.

Methods

We describe eight interrelated factors depicted in the framework that represent major themes in gambling ranging from the specific (gambling environment, exposure, gambling types, and treatment resources) to the general (cultural, social, psychological, and biological influences). After outlining the framework development and collaborative process, we highlight new topics for the recent update that reflect changes in the gambling landscape and prominent discourses in the scientific community. Some of these topics include social and economic impacts of gambling, and a new model of understanding gambling related harm.

Discussion and conclusions

We address the relevance of the CFHG to the gambling and behavioral addictions research community. Harm-based frameworks have been undertaken in other areas of addiction that can both inform and be informed by a model dedicated to harmful gambling. Further, the framework brings a multi-disciplinary perspective to bear on antecedents and factors that co-occur with harmful gambling.

Open access