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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Jakopič, A. Verbruggen, R. Eykens, F. Kehoe, H. Kühn, Y. Kushigeta, U. Jacobsson, J. Bauwens, S. Richter, R. Wellum, and Y. Aregbe

Abstract  

In nuclear safeguards, precise and accurate isotopic analyses are needed for two major elements from the nuclear fuel cycle: uranium and plutonium. This can be achieved by Isotope Dilution Mass Spectrometry (IDMS), which is one of the most reliable analytical techniques for the determination of plutonium amount content to a high level of accuracy. In order to achieve reliable isotope measurements isotopic reference materials with certified amount of plutonium and isotopic composition are required. At the Institute for Reference Materials and Measurements (IRMM) various plutonium spike reference materials for isotopes 239Pu, 240Pu, 242Pu and 244Pu are available. This enabled the setup of an inter-calibration campaign inter-linking selected plutonium spikes on a metrological basis applying state-of-the-art measurement procedures. The aim of this campaign is threefold: firstly to perform measurements on selected plutonium spike isotopic reference materials for quality control purposes, secondly to verify the amount content and the isotopic composition of the recently produced IRMM-1027m large sized dried (LSD) spikes and thirdly to demonstrate IRMM’s measurement capabilities for plutonium analysis via external quality tools. The obtained results using various spike isotopic reference materials will be presented and discussed in this paper. The measurement uncertainties of the IDMS results were calculated according to the guide to the expression of uncertainty in measurement (GUM).

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Abstract  

The calorimetry exchange (CALEX) program is administered by New Brunswick Laboratory (NBL). The main objective of the program is to provide an independent verification of the internal quality control practices in nuclear material safeguards facilities making plutonium accountability measurements by non-destructive calorimetry/gamma spectrometry techniques. Facilities measure the calorimetric power, and plutonium and 241Am isotope abundances of CALEX program standards using routine accountability procedures. The measurement results as well as two other quantities (effective specific power and plutonium mass) calculated from these results are evaluated for accuracy (or bias) and precision. In this paper, a limited number of measurement results of a CALEX program standard (identified as Calex I) are evaluated with specific goals to identify a suitable method for uncertainty estimation and to identify the major contributors to the uncertainties. In order to achieve the goals, the Calex I measurement results were evaluated using two different methods: the first method confined to uncertainty estimation from random variations of the measurement results alone, and the second method providing a more comprehensive evaluation of uncertainties from both the measurements and the characterized values of the measured standard according to the Guide to the Expression of Uncertainty in Measurement (GUM). The results of this study, and a subsequent study extended to a larger number of results in the CALEX program database, are expected to provide relevant input for developing the International Target Values for plutonium measurements by the calorimetry/gamma spectrometry method.

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Abstract  

A direct simple and fast method was established, to overcome the influence of low and high level impurities on the measurement of 235U/238U isotopic ratio in nuclear spent fuel safeguard by thermal ionization mass spectrometry (TIMS), by using refractory metal oxide. The addition of refractory metal oxides forming solution (RMOFS), in certain proportions alongside with the spent fuel solution on the sample filaments were found to be useful during the analysis of uranium isotopic ratio by TIMS. RMOFS (with oxide melting point exceeding 2,000 °C), and particularly that of magnesium, were found to be very effective in improving the quality of the ion signal of 235U and 238U, when added without the need for prior purification. Solutions of chromium, cerium, thorium, and magnesium were investigated, to select the more convenient one, and it was found that magnesium was very useful to start with. The method was very simple, improve both the accuracy and precision of the collected data, reduce the time required to achieve steady uranium pilot signal, and hence the over all time of the analysis, regardless of the level of impurities present.

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Abstract  

Neutron multiplicity analysis has been a valuable technique for safeguards measurements of plutonium oxide and mixed oxides. Historically, most of these measurements have been performed using shift register based electronics. The shift register data acquisition lacks certain flexibility because the basic coincidence parameters (e.g., pre-delay, gate width, and long delay) must be fixed prior to the start of the measurement and the values may potentially, therefore, be sub optimal. List mode or time stamped data acquisition records the arrival time of each pulse thereby preserving the history of the pulse stream and allowing analysis and reanalysis using software analogs to the shift register circuit with adjustable parameters. Until recently, the data rates encountered in the assay of modest amounts of plutonium using efficient multiplicity counters were beyond the capacity of readily available personal computers. The calibration of the large epithermal neutron multiplicity counter (LEMC) for assay of plutonium scrap materials is used as a vehicle to compare the performance of the multiplicity shift register and a commercially available list mode acquisition module.

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Abstract  

The concentration of thirty-four elements each in Ghanaian dried tobacco leaves and snuff (powdered tobacco) have been determined using instrumental neutron activation analysis (INAA). The concentration of Hg, Cr, As and Cd in both set of samples were found to be in excess of WHO limits for drinking water, thus indicating potential toxicity of the samples. Cr, Cd, Sb and Cu were two to eight times high, whilst As and Hg were comparable in powdered tobacco and tobacco leaves. The aim of the study was to determine the pattern of elemental concentrations and the toxicological strengths in both tobacco leaves and tobacco powder. The results indicated that the toxicity of the snuff was higher than the tobacco. This indicated strongly that from the medical point of view, the level of toxic accumulation in users might be potentially high in the tobacco powder compared to the leaves. Thus, education of the Ghanaian public on the threshold value of toxic elements contained in both set of samples was suggested to safeguard users against these addictives.

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Safeguarding of the Intangible Cultural Heritage. Museum International , 56(1–2): 140. Republic of South Africa Aikawa N. An historical overview of the protection of the UNESCO International Convention for the Safeguarding of the

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The paper discusses the issue whether art and works of art created by artists can be assessed using legal means. The paper provides an overview of the different Hungarian constitutional provisions governing artistic freedom from 1949 to the present, and examines the possible components of freedom of arts as a fundamental right, within the confines of the Hungarian legal system. According to the author, the subjective side of the artistic freedom integrates into the fundamental right of freedom of expression, ie artistic expression is free, but it does not require a separate, specific protection under constitutional law. However, the specificities of artistic expression as factors influencing the scope of the freedom of expression might be taken into account, e.g. symbolic speech, the specificities of a genre or the time elapsed since publication). Hence, works of art and literary pieces are to be treated as specific, unique forms of opinions – they are presented as a form of freedom of expression but this does not go beyond the boundaries of freedom of expression as a fundamental right. At the same time, the regulation of art, irrespective of this, might be justified even in the Fundamental Law. Setting requirements for the state (the objective obligation of the state to safeguard the institutions of fundamental law) is a precondition for the birth and preservation of works of art, which constitutes the objective side of artistic freedom without any specific subject and denotes its specific constitutional content But, an appropriate level of protection for freedom of expression ensures that this recognition should not have any detrimental consequences for freedom of arts.

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A polycystás ovarium szindróma a leggyakoribb heterogén endokrin rendellenesség reproduktív korú nőkben. A szindróma továbbra is rejtélyes rendellenesség, amelynek etiológiája még nem tisztázott. Családi előfordulása viszonylag gyakori polycystás ovarium szindrómában szenvedő betegek körében, ami jelentős genetikai komponensre utal, jóllehet, az öröklődés módja nem tisztázott. A szerzők orvosi irodalmi adatok alapján áttekintették a genetikai és környezeti tényezők szerepét a polycystás ovarium szindróma kialakulásában. A mai napig még nem azonosítottak olyan gént, ami okozza vagy jelentős mértékben hozzájárul a kórkép fenotípusának kialakításához. A polycystás ovarium szindrómát olyan genetikai rendellenességnek kell tekinteni, amelyben számos genetikai és környezeti tényező kölcsönhatása határozza meg a heterogén klinikai és biokémiai fenotípust. Összefoglalva a jelenlegi bizonyítékokat, a szerzők arra a következtetésre jutottak, hogy a környezeti tényezők azonosítása és módosítása lehetségessé teszi azon személyek egészségének hatékonyabb védelmét, akiknél a genotípus vagy korábbi környezeti hatások hajlamosítanak a betegség kifejlődésére. Orv. Hetil., 2013, 154, 650–657.

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Corporate governance has become increasingly important in developed and developing countries just after a series of corporate scandals and failures in a number of countries. Corporate governance structure is often viewed as a means of corporate success despite prior studies reveal mixed, somewhere conflicting and ambiguous, and somewhere no relationship between governance structure and performance. This study empirically investigates the relationship between corporate governance mechanisms and financial performance of listed banking companies in Bangladesh by using two multiple regression models. The study reveals that a good number of companies do not comply with the regulatory requirements indicating remarkable shortfall in corporate governance practice. The companies are run by the professional managers having no duality and no ownership interest for which they are compensated by high remuneration to curb agency conflict. Apart from some inconsistent relationship between some corporate variables, the corporate governance mechanisms do not appear to have significant relationship with financial performances. The findings reveal an insignificant negative impact or somewhere no impact of independent directors and non-independent non-executive directors on the level of performance that strongly support the concept that the managers are essentially worthy of trust and earn returns for the owners as claimed by stewardship theory. The study provides support for the view that while much emphasis on corporate governance mechanisms is necessary to safeguard the interest of stakeholders; corporate governance on its own, as a set of codes or standards for corporate conformance, cannot make a company successful. Companies need to balance corporate governance mechanisms with performance by adopting strategic decision and risk management with the efficient utilization of the organization ’s resources.

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://www.shipman-inquiry.org.uk Safeguarding Patients: Lessons from the Past – Proposals for the Future, paras 10.91–10.98; The Fifth Report of the Shipman Inquiry, on-line: http://www.shipman-inquiry.org.uk Olayiwola, A. O., Olufunmilay

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