[en] First making a necessary distinction between the concepts of protection and safety, the author then goes on to unequivocally place the former as the backbone of the latter and to define the effects and risks of exposure to radiations from different standpoints (health, hereditary or potential). The real challenges for the future are those that affect the largest number of people: protection against natural radiation; protection for patients and the link between safety and protection. The finally looks at the existing international standards and admits the existence of inter-governmental divergences that, to his understanding, prevent the establishment of a true international system of protection and safety. (Author)

[en] The International Commission on Radiological Protection (ICRP) established the Task Group 84 Initial Lessons Learned from the NPP Accident in Japan vis-a-vis the ICRP System of Radiological Protection. This TG 84 Will compile lessons learned related to the efforts carried out to protect people against radiation exposure during and after the emergency exposure situation caused by the accident. In light of these lessons, the report of the TG will consider the suitability of ad hoc recommendations for the ICRP system of radiological protection for dealing with this type of emergency exposure. This paper describes the author opinion about the main aspects the TG 84 is examining. the intention is not to advance the findings and conclusions of the TG 84, but only to make a review of some of the radiation protection issues the are being discussed. (Author) 23 refs.

[en] This paper describes first the safety criteria of the Argentine regulatory authority with emphasis on the probabilistic safety criteria based on a limitation of individual risks. Then, it is presented a discussion on emergency criteria in relation to evacuation and relocation measures. Finally, the paper briefly describes the design of an Argentine offer for a safer heavy water reactor where these criteria are applied. 9 figs., 1 tab., 46 refs. (author)

[en] The present IAEA radiation protection programmes are described: the resources allocated to those contained within the Principal Programme on Technological Safety and on Physical Security amount to 105.429.000 US dollars for the biannual 2004-2005 period: that is: a specific radiological safety programme (radiological protection and safety of radiation sources) combined with a programme on radioactive materials transport safety, and another programme on the safe management of radioactive waste. The Programme on Radiological and Transport Safety contains sub-programmes on: improvements on radiological and transport safety infrastructures at national and global levels, information and communication networks on radiological safety, application of safety standards on IAEA's operations, occupational radiation protection, radiological protection of the patient, safety on the transport of radioactive materials and preparation and response to nuclear or radiological emergency situations. The Programme on Radioactive Waste also includes sub-programmes on: the improvement of radioactive waste infrastructures at national and global levels, networks of information and communication on radioactive waste management, safety policies and approaches for the final disposal of radioactive waste, technologies for the final disposal of radioactive waste, releases of radioactive materials to the environment under safe conditions, safe management of residual radioactive materials, technologies for the safe closure of installations and rehabilitation of sites and the safe management of sealed out-of-use sources. Finally, there are described the consultations with experts from IAEA Member States conducted during a great number of international Conferences, and the conversion of the received recommendations into Action plans, that approach the IAEA programmes to the changing needs of the world and to the scientific discoveries which are been produced. (Author)

[en] This paper reports a preliminary measurement of the ratio of branching ratios BR(B⁺ → J/ψK⁺)/BR(B⁰ → J/ψK⁰). The reconstruction of J/ψ's is done via the decay J/ψ→μ⁺μ^- while the K⁰_s's are identified through the decay K⁰_s→π⁺π^-. The data used was obtained at the Collider Detector at Fermilab from pp collisions at √s=1.8 TeV. There are several reasons why this measurement is important. It embodies the first observation of the decay mode B⁰ → J/ψK⁰_s at a hadronic machine and it permits measurement of the ratio of charged to neutral lifetimes and the BR(B⁰ → J/ψK⁰)

[en] We report on the magnetic and structural properties of two epitaxial La₂MnCoO₆ thin films grown on (001)-oriented SrTiO₃ (STO) substrates, prepared in order to achieve opposite characteristics: one showing perfect Co/Mn cation ordering and a single domain structure; and the second presenting strong B-site disorder. These two films (115 nm) were grown with different orientations. The ordered film with LMCO [110]//STO [001], and the second (disordered) with LMCO [001]//STO [001]. The former consistent with P2₁/n symmetry and the latter with Pbnm structure. Their different ferromagnetic properties are discussed.

[en] We have studied the magnetic and magnetotransport properties of Pr_0.50Ca_0.50CoO₃ (prepared using high pressure routes). We find that below the metal-insulator and spin state transition (MIT), the system can be described as a paramagnetic insulator. In this regime, it presents a considerable negative magnetoresistance (20%-40%), while above MIT the magnetoresistance is negligible or even slightly positive. These results seem in contradiction with the spin state picture usually drawn for this system.