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The International Atomic Energy Agency is an international organization that seeks to promote the peaceful use of nuclear energy, and to inhibit its use for any military purpose, including nuclear weapons. The IAEA was established as an autonomous organization on 29 July 1957. Though established independently of the United Nations through its own international treaty, the IAEA Statute, the IAEA reports to both the United Nations General Assembly and Security Council.The IAEA has its headquarters in Vienna, Austria. The IAEA has two "Regional Safeguards Offices" which are located in Toronto, Canada, and in Tokyo, Japan. The IAEA also has two liaison offices which are located in New York City, United States, and in Geneva, Switzerland. In addition, the IAEA has three laboratories located in Vienna and Seibersdorf, Austria, and in Monaco.The IAEA serves as an intergovernmental forum for scientific and technical cooperation in the peaceful use of nuclear technology and nuclear power worldwide. The programs of the IAEA encourage the development of the peaceful applications of nuclear technology, provide international safeguards against misuse of nuclear technology and nuclear materials, and promote nuclear safety and nuclear security standards and their implementation.The IAEA and its former Director General, Mohamed ElBaradei, were jointly awarded the Nobel Peace Prize on 7 October 2005. The IAEA's current Director General is Yukiya Amano. Wikipedia.

Zaman M.,Ballance Agri Nutrients Ltd New Zealand | Nguyen M.L.,International Atomic Energy Agency
Agriculture, Ecosystems and Environment | Year: 2012

In intensively dairy-grazed pastoral systems, urine patches are the major source of nitrogen (N) losses via gaseous emissions of ammonia (NH 3) and nitrous oxide (N 2O) and nitrate (NO 3 -) leaching. Minimizing these N losses can therefore enable substantial economic and environmental gains. However, the current practice like the blanket application of nitrification inhibitor (NI) such as dicyandiamide (DCD) in suspension form after grazing is not effective at reducing these N losses. The objective of this study was to identify the best time to apply a combination of urease (UI) and NI inhibitors to reduce these N losses from urine patches. A field experiment on Typic Haplustepts silt loam soil, near Lincoln, Canterbury, New Zealand was conducted. The treatments included: a control (no urine or inhibitor), urine alone at 600kgNha -1, and urine with either double inhibitor (DI) in solid form which consists of a mixture (1:7 ratio w/w) of UI (N-(n-butyl) thiophosphoric triamide (nBTPT-trade name Agrotain ®) and DCD or DCD alone at 10kgha -1 in suspension form. The DI or DCD was applied to undisturbed lysimeters/field plots 10 and 5 days prior to, the same day, and 5 days after urine application in autumn (May 2008) and again to new lysimeters and field plots in spring (September 2008). Overall there were 10 treatments: control, urine alone and urine with DI or DCD applied at the time of urine application, 5 days before or after urine application and 10 days before urine application. After these treatment applications in 2 seasons, soil ammonium (NH 4 +) and NO 3 - concentrations, soil pH, gaseous emissions of NH 3 and N 2O, and NO 3 - leaching were monitored for different period of time and pasture growth and N uptake were measured over a year. The DI applied 5 days prior to urine application was more effective in reducing the 3N losses of NH 3 volatilization, N 2O emissions and NO 3 - leaching than its corresponding or DCD treatment applied 5 days after urine application. The DI applied 5 days prior to urine application significantly reduced soil NH 4 + and NO 3 - production from applied urine and thus exhibited a minimal increase in soil pH compared with urine alone or with DCD treatments for 4-6 weeks during the two seasons. DCD consistently increased NH 3 volatilization when applied 5 or 10 days prior to or concurrently with urine, however it decreased N 2O emissions compared to urine alone in both seasons. Applying DI 5 days prior to urine application not only decreased N 2O emissions as much as DCD did, it also significantly decreased NH 3 volatilization by 38% in autumn and 28% in spring compared to urine alone. Applying DCD or DI in autumn was more effective than spring applications probably because of the lower soil temperature (<10°C) in autumn. Compared to urine alone, DI and DCD applied 5 days prior to urine application in autumn significantly reduced NO 3 - leaching by 58% and 43%, respectively since the leaching events occurred during the time when these inhibitors were effective (1-2 weeks for nBTPT and 4-6 weeks for DCD). Neither the DI nor DCD had any such significant effect on NO 3 - leaching losses after their spring application because the leaching events occurred 3-5 months after inhibitor application, which was beyond the time that these inhibitors could be effective. Pasture productivity was only significantly increased by the DI after autumn application, but no significant trend was observed after spring application. These results suggest that DI applied in solid form prior to grazing has the most potential to reduce the 3 key N losses in grazed pastoral system; and it therefore warrants further research to improve its longevity to control N losses for a longer period. © 2012 Elsevier B.V.

Goriely S.,Free University of Colombia | Capote R.,International Atomic Energy Agency
Physical Review C - Nuclear Physics | Year: 2014

Some 27 Hartree-Fock-Bogoliubov (HFB) mass models have been developed by the Brussels-Montreal collaboration. Each of these models has been obtained with different model prescriptions or corresponds to a significantly different minimum in the parameter space. The corresponding uncertainties in the mass extrapolation are discussed. In addition, for each of these models, uncertainties associated with local variations of the model parameters exist. Those are estimated for the HFB-24 mass model using a variant of the backward-forward Monte Carlo method to propagate the uncertainties on the masses of exotic nuclei far away from the experimentally known regions. The resulting uncertainties are found to be significantly lower than those arising from the 27 HFB mass models. In addition, the derived correlations between the calculated masses and between model parameters are analyzed. © 2014 American Physical Society.

Boulyga S.F.,International Atomic Energy Agency
International Journal of Mass Spectrometry | Year: 2011

During the past few decades releases of man-made radionuclides into the biosphere have created environmental contamination that has provoked public concern. This has also raised the need to accurately and in a timely manner determine the quantities of radionuclides in environmental samples and in bio-assays in order to assess their potential impact on public health. The wide spectrum of emission sources has resulted in heterogeneous structures and different isotopic compositions of the contamination that, in turn, has produced new and very specific elemental and isotopic features. Nowadays, mass spectrometry is increasingly used for the determination of many long-lived radionuclides with low specific activities in environmental and biological samples. In summary, the merits of particular mass spectrometric methods include (i) low detection limits (ICP-MS, TIMS, etc.), (ii) high precision of the measured isotopic ratios (multi-collector ICP-MS and TIMS), (iii) high selectivity and abundance sensitivity (RIMS, AMS), and (iv) possibility for a spatially resolved isotope analysis (SIMS, LA-ICP-MS). Mass spectrometric analysis of long-lived radionuclides has been employed in radiobiology and biomedical studies, environmental monitoring and remediation, climate research, and forensics. The implementation of imaging inorganic mass spectrometry in proteomic research is highly promising for the study of radionuclide speciation mechanisms in organs and tissue on a bio-molecular level. This paper summarises specific features of major radioactive contaminations that have occurred during the last few decades and discusses the merits of modern mass spectrometric techniques, with examples of the determination of long-lived isotopes of actinides and fission products in biological samples. © 2011 Elsevier B.V.

Boulyga S.F.,International Atomic Energy Agency
Mass Spectrometry Reviews | Year: 2010

The variations in the isotopic composition of calcium caused by fractionation in heterogeneous systems and by nuclear reactions can provide insight into numerous biological, geological, and cosmic processes, and therefore isotopic analysis finds a wide spectrum of applications in cosmo- and geochemistry, paleoclimatic, nutritional, and biomedical studies. The measurement of calcium isotopic abundances in natural samples has challenged the analysts for more than three decades. Practically all Ca isotopes suffer from significant isobaric interferences, whereas low-abundant isotopes can be particularly affected by neighboring major isotopes. The extent of natural variations of stable isotopes appears to be relatively limited, and highly precise techniques are required to resolve isotopic effects. Isotope fractionation during sample preparation and measurements and instrumental mass bias can significantly exceed small isotope abundance variations in samples, which have to be investigated. Not surprisingly, a TIMS procedure developed by Russell et al. (Russell et al., 1978. Geochim Cosmochim Acta 42: 1075-1090) for Ca isotope measurements was considered as revolutionary for isotopic measurements in general, and that approach is used nowadays (with small modifications) for practically all isotopic systems and with different mass spectrometric techniques. Nevertheless, despite several decades of calcium research and corresponding development of mass spectrometers, the available precision and accuracy is still not always sufficient to achieve the challenging goals. The present article discusses figures of merits of presently used analytical methods and instrumentation, and attempts to critically assess their limitations. In Sections 2 and 3, mass spectrometric methods applied to precise stable isotope analysis and to the determination of 41Ca are described. Section 4 contains a short summary of selected applications, and includes tracer experiments and the potential use of biological isotope fractionation in medical studies, paleoclimatic and paleoceanographic, and other terrestrial as well as extraterrestrial investigations. © 2009 Wiley Periodicals, Inc.

Rosenblatt E.,International Atomic Energy Agency
Frontiers in Oncology | Year: 2014

Countries, states, and island nations often need forward planning of their radiotherapy services driven by different motives. Countries without radiotherapy services sponsor patients to receive radiotherapy abroad. They often engage professionals for a feasibility study in order to establish whether it would be more cost-beneficial to establish a radiotherapy facility. Countries where radiotherapy services have developed without any central planning, find themselves in situations where many of the available centers are private and thus inaccessible for a majority of patients with limited resources. Government may decide to plan ahead when a significant exodus of cancer patients travel to another country for treatment, thus exposing the failure of the country to provide this medical service for its citizens. In developed countries, the trigger has been the existence of highly visible waiting lists for radiotherapy revealing a shortage of radiotherapy equipment. This paper suggests that there should be a systematic and comprehensive process of long-term planning of radiotherapy services at the national level, taking into account the regulatory infrastructure for radiation protection, planning of centers, equipment, staff, education programs, quality assurance, and sustainability aspects. Realistic budgetary and cost considerations must also be part of the project proposal or business plan. © 2014 Rosenblatt.

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