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In the framework of its R&D activities to support the metal industry, the Laboratory for Integration of Systems and Technology of CEA Paris-Saclay started studies with the aim of characterizing scrap metal by means of neutron activation analysis. This involves irradiating samples of scrap metal with a pulsed-neutron source in order to determine the copper composition (mainly Cu-65 and Cu-63). In this scope, the use of a LaBr3 detector with an energy resolution of 14.6 keV at 661 keV is hereby investigated to carry out acquisitions during and between the irradiation pulses. As pointed out in literature, the LaBr3 inorganic scintillator might suffer some damage in a neutron-rich environment. Understanding the degradation of the energy resolution of such detector due to a high dose environment is essential to analyse the recorded signal. In this context, the work described in the present paper explores the coherent creation of neutron induced activation products as well as their respective delayed gamma rays in the quite well established LaBr3 inorganic scintillator by the mean of two steps Monte Carlo simulations performed first with the DCHAIN code, and secondly with the PHITS general purpose Monte Carlo particle transport code. Coherence was shown between neutron-induced activation gamma rays and the isotopes created in the crystal, and between the isotopes created and their decay through time. Thus, this study validate the two-step calculation scheme with PHITS and DCHAIN for both the time and energy aspects.

Since the out-of-pile semi-integral tests performed at Studsvik in 2011 for the NRC [1] and the Halden Loss-Of-Coolant Accident (LOCA) test series IFA-650 [2], a major safety interest has raised for Fuel Fragmentation, Relocation and Dispersal (FFRD) during a LOCA sequence. In addition to the characteristics of the fuel ejected from the rod after the clad failure, the fuel behaviour before the clad failure is still to be investigated, especially its fragmentation and its possible relocation within the rod during the clad ballooning phase. Furthermore, the chronology and the sequencing of these phenomena is of particular interest. For this purpose, the VINON-LOCA program, lying in the framework of a trilateral agreement between EDF, Framatome and CEA, is aimed at performing Out-Of-Pile heating tests on irradiated repressurized fuel rods, reproducing a typical Loss Of Coolant Accident thermal sequence. The VINON-LOCA experimental set-up is located in the so-called VERDON lab of the LECA-STAR hot cell complex. This lab was dedicated to the VERDON-ISTP program [3]. The VINON-LOCA set-up is thus largely instrumented for addressing not only these FFRD topics, but also Fission Gas Release (FGR), combining both online measurement (gamma stations, gamma camera, acoustic sensor, pressure, temperatures, flow meters, microGC…), and preand post-test characterization (gamma scanning, tomography, metrology, fuel fragments weighing and sieving, gas analyses…). An extensive and substantial qualification campaign has been performed to validate the furnace design regarding the desired test conditions, and to qualify the instrumentation. Following some preliminary modelling and calculations, it has included tests on an out-of-cell twin mockup and tests on dummy inactive rods in the hot cell. This allowed achieving successfully the first experimental qualification test of the program end of 2019 on an irradiated UO2 fuel rodlet. A second irradiated experiment is planned with increased instrumentation capabilities, notably a 2D gamma camera for online fuel motion detection.

Objective: To investigate trends in breast cancer mortality in New Zealand women, to corroborate or negate a causal association with service screening mammography., Method: Cumulated mortality rates from breast cancer deaths individually linked to incident cases diagnosed before and after screening commencement were compared, in women aged 50-64 (from 2001) and aged 45-49 and 65-69 (from 2006). Trends and differences in aggregate invasive breast cancer mortality (1975-2013) were assessed in relation to introduction of mammography screening targeting women aged 50-64 and 45-69. Joinpoint analysis was also undertaken., Results: The reduction in incidence-based cumulated breast cancer mortality before and after the introduction of screening was -15% (p = 0.006) for women aged 45-69, and 17% (p = 0.005) for those aged 50-64. Aggregate mortality declined by -34% (2005-13 compared with 1992-98) in the age group 50-64, and by -28% among women aged 45-49 and -25% among women aged 65-74. For women aged 50-64 the 2-joinpoint model shows a 1990 turning point, from prior rising mortality to a mean -1.8% decline per annum, coinciding with improvements in primary treatment of breast cancer; and a steepening of the decline (-3.0% p.a.) from the late 1990s, coinciding with the introduction of service mammography screening., Conclusion: Breast cancer mortality declines occurring since the advent of screening mammography in New Zealand are consistent with other incidence-based and aggregate studies of screening mammography in populations, individual-based cohort studies, and randomized controlled trials.

The latest release of the large subunit ribosomal database contains 429 sequences, yet only 10 (six nuclear and four mitochondrial) are derived from parasites of the phylum Apicomplexa. Three of these (all Toxoplasma gondii) were previously contained in the 1994 release of the database. As an initiative towards an understanding of ribosomal gene organization in the Apicomplexa, the primary sequence of the large subunit (LSU) rDNA of Neospora caninum is presented, and compared with a consensus sequence derived for the LSU rDNA of T. gondii. Nucleotide differences observed between these two taxa in the D2 expansion segment (or domain) (also called the C1/C1' region) of the LSU rDNA were incorporated into a primer that forms the basis of a species-specific polymerase chain reaction (PCR) for N. caninum. The D2 domain of the LSU rDNA, therefore, represents a new genetic marker that can be used for the differentiation and identification of Neospora from other cyst-forming coccidia., (Copyright 1998 Academic Press Limited)