Abstract
Accelerator-produced radioisotopes are widely used in modern medicine, for imaging, for cancer therapy, and for combinations of therapy and diagnostics (theragnostics). Clinical trials are ...well advanced for several radioisotope-based treatments that might open the way to a strong request of specific accelerator systems dedicated to radioisotope production. While cyclotrons are the standard tool in this domain, we explore here alternative options using linear accelerators. Compared to cyclotrons, linacs have the advantage of modularity, compactness, and reduced beam loss with lower shielding requirements. Although in general more expensive than cyclotrons, linacs are competitive in cost for production of low-energy proton beams, or of intense beams of heavier particles. After a review of radioisotopes of potential interest, in particular produced with low-energy protons or helium, this paper presents two linac-based isotope production systems. The first is a compact RFQ-based system for PET (Positron Emission Tomography) isotopes, and the second is an alpha-particle linac for production of alpha-emitters. The accelerator systems are described, together with calculations of production yields for different targets.
Abstract
A first beam dynamics and RF design of an Alvarez-type drift tube linac (DTL) has been defined in the framework of the EU project, HITRIplus. It is meant primarily as a carbon (
12
C
4+
) ...and helium (
4
He
2+
) ion injector of a compact synchrotron for patient treatment. As a second implementation, helium particle acceleration with a higher duty cycle (10%) enables radioisotope production. The 352.2 MHz structure efficiently accelerates ion species with A/q=3 and 2, in the energy range from 1 to 5 MeV/u and for a beam current up to ∼0.5 mA. The design extends to a full length of ∼6.4 meters. Permanent magnet quadrupoles are utilized all along the DTL for focusing both ion beams. This paper presents a first-phase analysis towards a realistic DTL design capable of providing full beam transmission and minimum overall emittance increase for both A/q values.
Participant dropouts can reduce the power of allergen immunotherapy clinical trials. Evaluation of the dropout rate and reasons for dropout are important not only in the planning of clinical studies ...but are also relevant for adherence to immunotherapy in daily clinical practice. A systematic review was carried out in order to establish the overall dropout rate among published double‐blind, placebo‐controlled randomized clinical trials of sublingual immunotherapy for respiratory allergic diseases. Dropouts were analysed in regards to allergen, formulation, treatment schedule, participant age, study size, number of centres and type of allergic disease. Relative dropout rates in placebo and active groups as well as reasons for dropout were also assessed. A total of 81 studies, comprising 9998 patients, were included. Dropout rates in sublingual immunotherapy controlled studies do not appear to be a major problem with a composite dropout percentage of 14% (95% CI:11.9–16). Furthermore, they are not different for active compared to placebo‐treated participants. This lends support to the positive clinical outcomes seen in meta‐analyses of these trials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
The yearly energy requirements of room temperature (RT) and superconducting (SC) magnet options of a new hadron therapy (HT) facility are compared. Special reference is made to the layouts ...considered for the proposed SEEIIST facility. Benchmarking with the RT CNAO HT centre in Pavia (Italy) was carried out. The energy comparison is centred on the different synchrotron solutions, assuming the same injector and lines in the designs. The beam current is 20 times higher than in present generation facilities: this allows efficient multi-energy extraction (MEE), which shortens the therapy treatment and is needed especially in the SC option, because of the slow magnet ramping time. Hence, power values of the facility in the traditional mode were converted into MEE ones, for a fair comparison between RT and SC magnets. Cryocoolers (c.c.) and a liquefier are also compared, for synchrotron refrigeration. This study shows that a RT facility in MEE mode requires the least average energy, followed by the SC synchrotron solution with a liquefier, while the most energy intensive solution is the SC one with c.c.
There is little consistency in how severe mental illness (SMI) is defined in practice, and no operational definitions.
To test two operationalized definitions, based on the National Institute of ...Mental Health (1987) definition: the first uses three criteria (diagnosis of psychosis; duration of service contact > or = 2 years; GAF score < or = 50), the second only the last two.
Annual prevalence rates of SMI in two European catchment areas for each criterion and the criteria combined were calculated.
The first definition produced rates of 2.55 and 1.34/1000 in London and Verona, respectively; the second permitted an additional 0.98/1000 non-psychotic disorders to be included in Verona.
The three-dimensional definition selects a small group of patients with SMI who have psychotic disorders. The two-dimensional approach allows estimates of SMI prevalence rates which include all forms of mental disorder.
Abstract
Recent years have seen an increased interest in the use of helium for radiation therapy of cancer. Helium ions can be more precisely delivered to the tumour than protons or carbon ions, ...presently the only beams licensed for treatment, with a biological effectiveness between the two. The accelerator required for helium is considerably smaller than a standard carbon ion synchrotron. To exploit the potential of helium therapy and of other emerging particle therapy techniques, in the framework of the Next Ion Medical Machine Study (NIMMS) at CERN, the design of a compact synchrotron optimised for acceleration of proton and helium beams has been investigated. The synchrotron is based on a new magnet design, profits from a novel injector linac, and can provide both slow and fast extraction for conventional and FLASH therapy. Production of mini-beams, and operation with multiple ions for imaging and treatment are also considered. This accelerator is intended to become the main element of a facility devoted to a parallel programme of cancer research and treatment with proton and helium beams, to both cure patients and contribute to the assessment of helium beams as a new tool to fight cancer.
Worldwide efforts to tackle the nature of exotic nuclei comprise the construction of new-generation Radioactive Ion Beam facilities. The Italian community is deeply involved in the process and the ...construction of SPES at Legnaro National Laboratories (INFN) is progressing. This contribution describes the layout of SPES in all its flavours, from Nuclear Physics to Applications in Nuclear Medicine and Neutron Physics. In particular, the status of the SPES-β ISOL facility, together with some of the relevant physics cases and the associated equipment are described.
Abstract
The ADIGE (Acceleratore Di Ioni a Grande carica Esotici) injector consists of an electrostatic 1+ beam line, equipped with ion sources able to produce a wide variety of beams, coupled to a ...magnetic beam line, where charge multiplication is accomplished by implementing an Electron Cyclotron Resonance (ECR) based charge breeder. The injector is totally integrated in the SPES (Selective Production of Exotic Species) beam line, to allow the post-acceleration of radioactive ions and is now in an advanced phase of installation. The electrostatic 1+beam line has been put into operation and is now producing beams from alkali metals. This contribution concerns the first results of the beam commissioning of this part of the injector, with the description of the initial debug phase and the solutions adopted to ensure a reliable and continuous operation. Preliminary results of the 1+ beam line characterization will be shown, with a comparison between simulated and measured emittances.
The Selective Production of Exotic Species (SPES) facility is under construction at INFN-LNL: aim of this project is the production, ionization and post-acceleration of radioactive ions to perform ...forefront research in nuclear physics. Radioactive species will be produced by fissions induced by a proton beam impinging on an UCx target: the proton beam will be delivered by a room temperature cyclotron (built by the Best Company) with a maximum energy of 40MeV and 0.25mA of maximum current. The radioactive species produced in the Target-Ion-Source system, extracted as a 1+ beam, cooled in a RFQ-cooler and purified from the isobars contaminants through a High Resolution Mass Spectrometer (HRMS). In order to allow post acceleration with the superconducting linac ALPI at INFN-LNL (up to 10MeV/A for A/q=7), an ECR-based charge breeding technique (ECR-CB) was chosen: in particular the SPES-CB was developed by the LPSC Grenoble on the basis of the Phoenix booster. The SPES-CB will be equipped with a complete test bench, totally integrated with the SPES beam line: in particular, in order to avoid beam contaminations induced by the impurities present inside the SPES-CB, and to have high transmission for a beam of very low intensity, special attention was paid not only to the transport efficiency but also to the resolution of the spectrometer downstream the charge breeder, with the design of a Medium Resolution Mass Spectrometer (MRMS). In the following paper the technical aspects connected with SPES-CB, its beam line and the transport of highly charged radioactive ions will be described.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Both subjective and objective information is necessary to assess quality of life (QOL).
To explore the role of subjective and objective QOL dimensions and their cross-sectional and longitudinal ...predictors.
The relationship between QOL, as measured by the Lancashire Quality of Life Profile (LQL), and demographic variables, diagnosis, psychopathology, disability, functioning, affect balance, self-esteem, service use and service satisfaction was investigated at two points in time, using factor analysis and multiple regression techniques.
One subjective and two objective LQL factors with strong face validity were identified. Cross-sectional predictors of the subjective factor were primarily subjective measures; longitudinally, few predictors of this factor were identified. The cross-sectional and longitudinal predictors of the objective factors were primarily demographic and observer-rated measures.
Subjective and objective data are distinct types of information. Objective measures may be more suitable in detecting treatment effects. Subjective information is necessary to complete the QOL picture and to enhance the interpretation of objective data.
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