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In the decommissioning of nuclear facilities, it is necessary to assess the radioactivity inventory for waste classification and management. For nuclear fusion experiments or accelerator-driven neutron sources, the main contribution to the radiological inventory comes from activation products and tritium. When water is used as coolant of components, it may be activated by neutrons with the consequent production of tritium, and short-lived oxygen and nitrogen isotopes. In most cases several chemical elements may be in solution or suspension in water, because of metallic pipes corrosion when occurring, or functional reasons, e.g. chemical conditioning, addition of antifreeze agent, etc. In this case other activation products could be present and need to be characterized. In this case study, a sample of the coolant of the ENEA Frascati Neutron Generator (FNG) has been radiologically, chemically and physically characterized. In such a facility, during the operation, a beam of deuterons is accelerated up to 300 keV and impacts on a tritiated target for producing 14 MeV neutrons exploiting the fusion reaction T(d,n)α. To avoid overheating in the area around the target, a water-cooling loop is used. After several years of operation, a sample of the fluid has been extracted to undergo a qualitative and quantitative analysis of the radionuclides inventory. Gamma spectrometry has not shown any presence of gamma emitters. On the other hand, Liquid Scintillation Counting (LSC) has provided evidence of the presence of beta emitters. It is known that tritium is expected to occur in the sample because of releases from the tritiated titanium target. This work concerns the development of a method to discriminate the tritium contribution with respect to the total beta activity within the FNG coolant. Since it is known that an unspecified percentage of an unknown anticorrosive agent was added to the water coolant, vacuum distillation has been used to extract purified water (containing only tritium) from the coolant sample leaving any (activated) non-volatile compound in the undistilled fraction. After distillation, any fraction has been investigated by Raman spectroscopy, to determine: a) the chemical composition of the colored anticorrosive agent, b) the efficiency of the separation. Afterwards, both fractions have been analysed by means of LSC, and results showed that the main contribution to sample activity is due to tritium and the activity values are consistent with the theoretical H atomic concentration in both fractions.

OBJECTIVE: The study aimed to evaluate the utility and safety of ancillary maneuvers during oocyte retrieval for patients with endometrioma that makes ovum pick-up hard due to poor ovarian surgical accessibility. PATIENTS AND METHODS: Cases of 251 women with ovarian endometriomas undergoing in vitro fertilization (IVF) in our infertility unit were retrospectively analyzed to evaluate the clinical IVF cycle outcomes after oocyte retrieval. Controls (n = 251) were age-matched women without endometriomas who underwent an uncomplicated oocyte retrieval. RESULTS: No statistically significant differences were observed between groups except for the number of oocytes retrieved, which was higher in the control group than in the group of women with endometrioma. On the contrary, there were no differences between the experimental groups in the fertilization rate and number of embryos and neither were there in the pregnancy and live birth rate. Moreover, the surgical complications were infrequent and similar between the two analyzed groups. Accidental or voluntary endometrioma punctures were not accompanied by increases in the risk of a pelvic infection. CONCLUSIONS: In conclusion, patients with endometrioma can undergo high-performance oocyte recovery procedures thanks to safe accessory maneuvers during the ovum pick-up. [ABSTRACT FROM AUTHOR]