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Abstract  

Three different spent control rods were obtained for direct-assay measurements and empirical sampling and analysis. They were: 1) a BWR cruciform control rod, 2) a PWR rod-cluster control assembly, and 3) a burnable poison-rod assembly. The dominant activity of the BWR cruciform control rod and the PWR burnable poison-rod assembly is60Co, whereas the PWR rod-cluster control assembly is dominated not only by60Co, but also by108mAg and110mAg, which are found in the Ag–In–Cd alloy of the absorber rods. The radionuclide inventories calculated for the three spent control rods from the empirical sampling data agree very well with data determined from the two direct assay methodologies. The concentration of108mAg in the rod-cluster control assembly will have to be considered when these types of spent control rods are prepared for waste disposal.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
D. Robertson
,
V. Thomas
,
H. Rieck
,
D. Haggard
,
W. Reece
,
J. Pappin
,
W. Hensley
,
D. Brown
,
C. Thomas
, and
P. Robinson

Abstract  

Battelle, Pacific Northwest Laboratories has recently developed, tested and field-demonstrated a technology for the direct assay of transuranic radionuclides (TRU), fission products, and activation products in a variety of radwaste packages generated at commercial nuclear power plants. This technology involves non-destructive passive neutron counting for determination of nanocurie/gram quantities of the TRU radionuclides. Direct gamma spectrometry combined with thermoluminescent dosimetry (TLD) and correlation analysis is also utilized to determine the concentrations of the fission and activation products present in the radwaste packages. Employing counting times of 10 to 20 minutes, a complete analysis of all radionuclides specified for assay by the U.S. Nuclear Regulatory Commission (in 10CFR61) prior to shallow-land disposal of commercial radwastes can be measured at concentrations at least tenfold below the least restrictive Class A waste catagory.

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Abstract

The treatment of human immunodeficiency virus (HIV) with antiretroviral (ARV) medications has revolutionised the care for these patients. The dramatic increase in life expectancy has brought new challenges in treating diseases of aging in this cohort. Cardiovascular disease (CVD) is now a leading cause of morbidity and mortality with risk matched HIV-positive patients having double the risk of MI compared to HIV-negative patients. This enhanced risk is secondary to the interplay the virus (and accessory proteins), ARV medications and traditional risk factors. The culmination of these factors can lead to a hybrid metabolic syndrome characterised by heightened ectopic fat. Cardiovascular computed tomography (CT) is ideal for quantifying epicardial adipose tissue volumes, hepatosteatosis and cardiovascular disease burden. The CVD risk attributed to disease burden and plaque morphology is well established in general populations but is less clear in HIV populations. The purpose of this review article is to appraise the latest data on CVD development in HIV-positive patients and how the use of cardiovascular CT may be used to enhance risk prediction in this population. This may have important implications on individualised treatment decisions and risk reduction strategies which will improve the care of these patients.

Open access

Abstract  

The previously established technique of analysis of neutron capture γ-rays for the determination of nitrogen in-vivo has been modified to make estimates of absolute quantities of nitrogen mass. Hydrogen is used as an internal standard and the nitrogen mass is determined from the observed ratio of nitrogen to hydrogen counts, together with the hydrogen mass, estimated from body parameters. Phantom and cadaver studies indicate that nitrogen mass can be estimated to ±4% or better by this means.

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Background

Internet gaming disorder (IGD) was introduced in the DSM-5 as a way of identifying and diagnosing problematic video game play. However, the use of the diagnosis is constrained, as it shares criteria with other addictive orders (e.g., pathological gambling).

Aims

Further work is required to better understand IGD. One potential avenue of investigation is IGD’s relationship to the primary reinforcing behavioral functions. This study explores the relationship between duration of video game play and the reinforcing behavioral functions that may motivate or maintain video gaming.

Methods

A total of 499 video game players began the online survey, with complete data from 453 participants (85% white and 28% female), were analyzed. Individuals were placed into five groups based on self-reported hours of video gaming per week, and completed the Video Game Functional Assessment – Revised (VGFA-R).

Results

The results demonstrated the escape and social attention function were significant in predicting duration of video game play, whereas sensory and tangible were not significant.

Conclusion

Future implications of the VGFA-R and behaviorally based research are discussed.

Open access

Abstract

A series of Mn–Ce(M) solids (M = K or Na), with molar ratios 100–0, 50–50 and 0–100 were prepared by co-precipitation of manganese and cerium nitrate from NaOH or KOH solutions at pH = 11. In addition, part of the solids precipitated with NaOH were dried and impregnated with a Cu2+ salt. The solids were characterized by XRD, Specific Surface Area, XPS and EDS. The characterization analyses show the formation of Mn mixed oxides with different oxidation states (Mn3+, Mn4+), for samples without Ce or Mn–Ce(M) 50–50. In the latter solid and in the one where there is no Mn, the formation of CeO2 (fluorite type) was detected. The samples were tested in the phenol removal in water at 100 °C and at atmospheric pressure with the aim to analyze the adsorbed species in the first stage of the adsorption-oxidation mechanisms. The results indicate, on the one hand, that [MnOx] is the active species in the process and that the most active solids are those that present (i) a higher concentration of OI, (ii) a higher amount of Mn4+ ions. DRIFT spectroscopy showed a possible mechanism of phenol adsorption on two sites, in the first one by H interaction of OH (phenol) with an OH of the catalyst and in the second, by the formation of a phenolate species between an O (OH phenol) and Mnn+.

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Orvosi Hetilap
Authors:
Attila Bokor
,
Erszébet Koszorús
,
Valentin Brodszky
,
Thomas D’Hooghe
,
WERF EndoCost Consortium
, and
János Rigó

Bevezetés: Az endometriosis az egyik leggyakoribb nőgyógyászati betegség, több mint 70 millió felnőtt és serdülő nőt érint világszerte. Célkitűzés: A szerzők az endometriosis diagnosztikus késedelmi idejének meghatározását, a sebészi, illetve kombinált műtéti kezelés hatékonyságának vizsgálatát, valamint a betegek életminőségének felmérését tűzték ki célul. Módszer: A beválogatási kritériumoknak megfelelő 240, endometriosisban szenvedő nőből 84 vett részt a retrospektív és prospektív kérdőíves felmérésben. Eredmények: A tünetek kezdetétől a diagnózisig átlagosan 3,9 év telt el. A tünetek fellépésekor a betegek 89%-a, a kezelést követő prospektíven vizsgált hónapokban 28%-a panaszkodott fájdalomról (p = 0,025). A sebészi kezelés és a műtéti terápiával kombinált konzervatív kezelés hatékonysága között nem találtak szignifikáns különbséget (p = 0,85). A munkahelyi teljesítmény csökkenéséről a betegek 47%-a, míg a személyes kapcsolatok kedvezőtlen alakulásáról a vizsgálatban részt vevők 40%-a számolt be. Az életminőségre standardizált életévveszteség egy év alatt 0,147 volt. Következtetések: Jelen felmérés az első hazai prospektív, az endometriosis életminőségre gyakorolt hatását vizsgáló tanulmány. A betegségre hosszú diagnosztikus késés jellemző. Az endometriosis jelentősen rontja az életminőséget, de adekvát kezeléssel a panaszok csökkenthetők. Orv. Hetil., 2013, 154, 1426–1434.

Open access

Summary Due to growing environmental concerns and the need to use less energy-intensive building products, alternatives and improvements to Portland cement (PC) are being actively researched worldwide. Use of supplementary materials is now a common practice where PC is the predominant component of inorganic building products. This study aims to investigate the potential of magnesia (MgO), derived from a naturally occurring raw material magnesite, as a supplementary material. Results from mortar samples prepared with 10 and 20% replacements of ordinary Portland cement (OPC) by MgO are presented. DTA-TG was used to study and characterise the hydration behaviour of MgO in OPC environment after 3, 7, 14, 28, 56 and 90 days of moist curing. Microstructural and compressive strength determinations providing additional information on the influence of hydrated phases are also reported.

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Abstract  

The Comprehensive Test Ban Treaty calls for the monitoring of aerosol radionuclides throughout the globe. Pacific Northwest National Laboratory has developed the Radionuclide Aerosol Sampler/Analyzer (RASA) for the Department of Energy to automatically collect and measure radioactive aerosols from the atmosphere. The RASA passes high volumes of air through a 3MTM Substrate Blown Microfiber Media (SBMF) specifically designated as SBMF-40VF. It then automatically moves the filter media in front of a high-purity germanium detector and collects a gamma spectrum. If further analysis on the filter is desired, the filter is sent to a laboratory and radiochemical analysis is performed. This paper discusses the method of dissolution of the SBMF-40VF filter media and the separation of the radioisotopes of interest.

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