Co-Evolutionary Learning for Cognitive Computer Generated Entities

In this paper, an approach is advocated to use a hybrid approach towards learning behaviour for computer generated entities (CGEs) in a serious gaming setting. Hereby, an agent equipped with cognitive model is used but this agent is enhanced with Machine Learning (ML) capabilities. This facilitates the agent to exhibit human like behaviour but avoid an expert having to define all parameters explicitly. More in particular, the ML approach utilizes co-evolution as a learning paradigm. An evaluation in the domain of one-versus-one air combat shows promising results

Preferences of Agents in Decentralized Task Allocation

The ability to express preferences for specific tasks in multi-agent auctions is an important element for potential users who are considering to use such auctioning systems. This paper presents an approach to make such preferences explicit and to use these preferences in bids for reverse combinatorial auctions. Three different types of preference are considered: (1) preferences for particular durations of tasks, (2) preferences for certain time points, and (3) preferences for specific types of tasks. We study empirically the tradeoffs between the quality of the solutions obtained and the use of preferences in the bidding process, focusing on effects such as increased execution time. We use both synthetic data as well as real data from a logistics company. © 2009-IOS Press

Radionuclide Research Activities at LASA – UNIMI and INFN during 2014

The target is to present the upgrading and the new results, obtained during 2014 at LASA Laboratory about the reserchers related to the radionuclides production for biomedical and environmental applications

Production of 186gRe radionuclide by deuterons for theragnostic medicine

Theragnostic medicine is a new integrated therapeutic system which can diagnose, deliver targeted therapy, and monitor the response to therapy. Many of the \u201cneutron-rich\u201d radionuclides suitable for metabolic radiotherapy are produced by nuclear reactor with a very low specific activity (A S). In selected cases, they can be produced by bombardment of targets by charged particle beams in \u201cNo Carrier Added Form\u201d with very high A S. If the irradiations are made with deuteron beams some more advantages are obtained, as described in this paper, through 186gRe production, reported as an example

Experimental excitation functions for PD-103 produced by deuteron beams

Brachytherapy was developed to treat prostate cancer 50 years ago. It consists in the implantation of Ti or SS seeds containing suitable radionuclides: nowadays only three radionuclides are available for use in low dose rate \u2013 LDR - prostate brachytherapy: I-125 (T1/2 = 59.4 d, mean photon energy emitted: 21 keV), Pd-103 (T1/2 = 17 d, mean photon energy emitted: 27 keV), and Cs-131 (T1/2 = 9.7 d, mean photon energy emitted: 29 keV). Pd-103 is an effective alternative to I-125 for high grade, rapidly growing cancer because of its faster dose rate that also raise thanks to possible differences in external tissue complications. So it is important to study the production optimization of Pd-103 radionuclide. Nowadays Pd-103 production by accelerator is based exclusively on the irradiation of rhodium metal targets with 18 MeV protons via Rh-103(p, n)Pd-103 reaction. We have studied the possibility to produce it by deuteron beams irradiation, which presents indisputable advantages. A new set of excitation functions for Rh-103(d,2 n)Pd-103 was measured and compared with the only other two sets present in the literature. The thin-target yields have been plotted as a function of their average energy into the targets and were fitted with the best mathematical functions. By integration of these functions the calculated thick-target yields were obtained, in order to find the optimized couple of irradiation energy and energy loss inside the thick target to maximize the production of the radionuclide of interest

Radionuclides production by proton and deuteron beams irradiation

Theranostic medicine is a new integrated therapheutic system which can diagnose, deliver targeted therapy and monitor the response to therapy. This multifunctional platform is an emerging highlight in medicine that combines both diagnostic/imaging and therapeutic aspects: the nuclear physician can follow the real biodistribution of the radiopharmaceutical inside the patient after the injection and the follow-up during the repeated treatments. The radioisotopes used for metabolic radiotherapy are \u3b1, \u3b2 and Auger electron emitters. Many of them are also \u3b3 emitters and can be detected by gamma-camera, SPECT or PET. Many of these \u201cneutron reach\u201d radionuclides are produced by nuclear reactor with a very low specific activity - AS. In selected cases they can be produced by bombardment of targets by charged particle beams, in No Carrier Added Form \u2013 NCA - with very high AS. If the irradiations are made with deuteron beams some more advantages are obtained: 1) the higher stopping power in respect to the protons allows to employ targets with smaller thickness: the volume of reagents, the synthesis systems and the discharge of radioactive material for radioprotection purpose are smaller, the AS and chemical purity of the final product are higher. 2) deuterons usually present higher cross sections in compound nucleus region. We present some results obtained at our Laboratory for the production optimization of some theragnostic radionuclides

Lu-177g produced with high specific activity by deuteron irradiation for metabolic radiotherapy

Lu-177g is a low energy negatron emitter that, thanks to its favourable decay properties (t(1/2) = 6.734 d, negatron emission 100 %, E(\u3b2,max) = 489.3 keV, = 163 keV, E\u3b3 = 208.4 keV), is one of the most promising radionuclide to be used in nuclear medicine, especially in metabolic radiotherapy of cancer of small dimensions. This RN is mainly produced in thermal nuclear reactor in two different ways: the first in carrier added (CA) form by (n,\u3b3) reaction on enriched target of Lu-176 leading to a lower specific activity (AS), compared with the theoretical carrier free value AS(CF) = 4.05 GBq\u2022\u3bcg^-1, the second in no carrier added (NCA) form by (n,\u3b3) reaction on enriched target of Yb-176 followed by negatron decay leading, after selective separation of Lu from Yb, to a higher AS. This latter case shows no evidence of production of the long-lived impurity Lu-177m. An alternative method is to produce Lu-177 by the deuteron activation of natural or enriched in 176Yb targets. In this case, the routes of interest are the indirect reaction Yb-176(d,p)Yb-177 that decays by negatron emission to Lu-177g and the direct reaction Yb-176(d,n)Lu-177(g+m). In order to optimize the Lu-177g production the thin target yields (ttys) of the nuclear reactions involved were measured as a function of the projectiles energy by the stacked-foil technique irradiating Yb targets of natural composition at the MC40 cyclotron of the JRC, Ispra, Italy, that can deliver deuterons with energies up to 19 MeV. The measurements, done at the radiochemistry laboratory of LASA by high resolution gamma spectrometry (HPGe detectors), were started few hours from the EOB (end of bombardment) and were carried on for many months, till more than one year, after the irradiation. The excitation functions of all radionuclides produced were measured and compared with the data, if present, published in the unique previous literature publication. It was determined the decay curve of Yb-177 and the growth curve of the cumulative (direct and indirect) production of Lu-177g. The analysis of these curves conduct to the evidence that the predominant route for the production of Lu-177g is the indirect reaction Yb-176(d,p)Yb-177, that decays to Lu-177g. The direct reaction Yb-176(d,n)Lu-177(g+m) is observable only above 13 MeV and contributes for only 4% of the total in correspondence of 14.6 MeV. In the spectra acquired one year from the EOB the \u3b3 lines of Lu-177m are not presented. By detection limit method the activity of Lu-177m at the EOB is been evaluated, in the worst case, less than 0.07% of total activity of Lu-177. The production of Lu-117g by deuteron irradiation of Yb targets will be competitive with neutron activation. The deuteron activation for 12 hours of a thick target of Yb-176 (100% enriched) with E(in) = 12.5 MeV, \u394E = 10.0 MeV, I = 100 \u3bcA can produce up to 10 GBq of cumulative Lu-177g

Radionuclide Research Activities at LASA during 2013 – UNIMI and INFN

The target is to present the upgrading and the new results, obtained during 2013 at LASA Laboratory about the reserchers related to the radionuclides production for biomedical and environmental applications