In recent years, most oil companies have shown a renewed interest for the Fischer–Tropsch synthesis, as a result of the current carbon scenario and the stringent regulations on sulphur level in ...fuels. As a matter of fact, an overview of the oil and gas reserves underlines the necessity of gas valorization to liquid fuel, especially referring to stranded gas reserves. Eni, in cooperation with IFP-Axens, has developed a new proprietary F–T process, and in this paper the catalyst design strategy and the process optimization will be discussed.
Accelerators for hadrontherapy: From Lawrence cyclotrons to linacs Amaldi, U.; Bonomi, R.; Braccini, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2010, Letnik:
620, Številka:
2
Journal Article
Recenzirano
Hadrontherapy with protons and carbon ions is a fast developing methodology in radiation oncology. The accelerators used and planned for this purpose are reviewed starting from the cyclotrons used in ...the thirties. As discussed in the first part of this paper, normal and superconducting cyclotrons are still employed, together with synchrotrons, for proton therapy while for carbon ion therapy synchrotrons have been till now the only option. The latest developments concern a superconducting cyclotron for carbon ion therapy, fast-cycling high frequency linacs and ‘single room’ proton therapy facilities. These issues are discussed in the second part of the paper by underlining the present challenges, in particular the treatment of moving organs.
The PSI Positron Production (P^{3} or P-cubed) experiment is a e^{+} source and capture system with the potential to increase by an order of magnitude the state-of-the-art e^{+} yield normalized to ...the drive linac energy, a highly desirable goal for future colliders. The experiment is framed in the FCC-ee injector study and will be hosted at SwissFEL, located at the Paul Scherrer Institute in Switzerland. This paper presents the P^{3} project at an advanced stage, with an emphasis on a capture system featuring a novel e^{+} matching device based on high-temperature superconducting solenoids, followed by two large aperture rf cavities surrounded by normal-conducting solenoids. The diagnostics design is also introduced, including monitors of charge, energy spectrum, and bunch-by-bunch longitudinal profile simultaneously for secondary e^{+} and e^{-}. The last chapter of the text overviews the currently ongoing installation at SwissFEL, including the beam transfer line, rf network, radiation protection, and other relevant activities toward the operation with e^{+} in the coming years.
This paper describes the acceleration tests performed at the Catania LNS Laboratory on a 3 GHz linac module of the side coupled type, which boosts the proton energy of a beam extracted from a ...cyclotron from 62 to 72 MeV. The output proton energy was measured with two devices: a NaI(Tl) crystal and a bending magnet. The experimental spectra are in good agreement with the calculated ones. From their shape it is obtained that (18A-3.0)% of the transmitted protons fall in a A-2 MeV interval centered around 72 MeV. This result is in good agreement with the 20% value derived from the simulation of the acceleration process. The measured energy of the accelerated protons was used to check that the shunt impedance of the structure is equal to the computed one within 3%. This was the first time that a 3 GHz structure has been used to accelerate protons, and the results of the tests have demonstrated that a high frequency linac can be used as a cyclotron booster.
The SwissFEL Injector Test Facility operated at the Paul Scherrer Institute between 2010 and 2014, serving as a pilot plant and test bed for the development and realization of SwissFEL, the x-ray ...Free-Electron Laser facility under construction at the same institute. The test facility consisted of a laser-driven rf electron gun followed by an S-band booster linac, a magnetic bunch compression chicane and a diagnostic section including a transverse deflecting rf cavity. It delivered electron bunches of up to 200 pC charge and up to 250 MeV beam energy at a repetition rate of 10 Hz. The measurements performed at the test facility not only demonstrated the beam parameters required to drive the first stage of an FEL facility, but also led to significant advances in instrumentation technologies, beam characterization methods and the generation, transport and compression of ultralow-emittance beams. We give a comprehensive overview of the commissioning experience of the principal subsystems and the beam physics measurements performed during the operation of the test facility, including the results of the test of an in-vacuum undulator prototype generating radiation in the vacuum ultraviolet and optical range.
The bone anabolic therapy Nardi, A.; Ventura, L.; Cozzi, L. ...
Aging clinical and experimental research,
10/2013, Letnik:
25, Številka:
Suppl 1
Journal Article
Recenzirano
Teriparatide (TPTD), the amino-terminal parathyroid hormone recombinant peptide PTH (1–34), is a drug with a proven anabolic action on the bone, effective in preventing vertebral and non-vertebral ...fragility fractures. Recent publications have investigated in great detail the TPTD action on the cortical bone, highlighting the increased strength in the critical zone of the hip with high risk of fracture in osteoporotic patients Poole (PLoS ONE 6:e16190,
2011
). In November 2002, TPTD was approved by the FDA for use in post-menopausal women and men with osteoporosis at high risk of fracture and in patients with glucocorticoid-induced osteoporosis and, since then, has been used to treat more than 1 million patients worldwide (J Bone Miner Res 27(12):2429–2437,
2012
). The unchanged safety profile and the well-known mechanism of action of this drug have led doctors to explore the use of TPTD in other conditions such as delayed fracture healing, non-union, osteonecrosis of the jaw, etc. The positive reports that have resulted from these studies are helping to hypothesize a new perspective on the wider use of this drug, but warrant further clinical investigation to consolidate these results.
OBJECTIVE To investigate the contribution of apoptosis in the development of the skeletal myopathy in chronic heart failure. DESIGN The electrophoretic pattern of myosin heavy chains (MHC), fibre ...cross sectional area, number of in situ nick end labelling (TUNEL) positive apoptotic myocyte nuclei, and the tissue levels of caspase-3, Bcl-2, and ubiquitin were determined in biopsies taken from the vastus lateralis muscle. The study involved nine patients with severe chronic heart failure caused by ischaemic heart disease and hibernating myocardium and five controls. RESULTS In chronic heart failure patients the vastus lateralis showed a significant increase of MHC2a and MHC2b and a greater degree of fibre atrophy, as demonstrated by the decreased cross sectional area. There was also an increased number of TUNEL positive apoptotic myocyte nuclei. Tissue concentrations of Bcl-2 were decreased, while those of caspase-3 and ubiquitin were increased. Peak oxygen consumption (Vo 2) was negatively correlated with the number of TUNEL positive nuclei and the fibre cross sectional area. There was a correlation between the number of apoptotic nuclei and the fibre cross sectional area, but no correlation between myosin heavy chains and number of apoptotic nuclei. CONCLUSIONS Myocyte apoptosis occurs in the skeletal muscle of patients with chronic heart failure, and its magnitude is associated with the severity of exercise capacity limitation and the degree of muscle atrophy. Muscle atrophy contributes to the limitation of exercise capacity, together with the increased synthesis of fast, more fatiguable myosin heavy chains.
In this paper we illustrate the tuning procedure we implemented to tune the traveling wave structures designed and constructed for the SPARC photo-injector energy upgrade. The procedure has been ...derived from that proposed and adopted for the CLIC structures at CERN (J. Shi et al., Tuning of clic accelerating structure prototypes at Cern, Proc. of LINAC 2010, Tsukuba, Japan, 2010). In the first part of the paper we go through the analytical formulas also illustrating and discussing an algorithm to tune the input and output couplers. A detailed description of the measurements we have done before and after the tuning of the SPARC C-band structure prototype is then illustrated.
LIBO is a proton accelerator that operates at
3
GHz
, the same frequency as the one adopted in the about 7500 electron linacs used for radiotherapy all over the world. Such a high frequency was ...chosen to obtain a large gradient (on average more than
10
MV/m
), and thus a short linac (about
15
m
) to boost the energy of the protons, extracted at about
60
MeV
from a cyclotron, up to the
200
MeV
needed for the treatment of deep-seated tumours.
This paper describes the design study of the full
3
GHz
Side Coupled Linac (modular structure, nine modules) and the construction and tests of the LIBO prototype (first module), which was built to accelerate protons from 62 to
74
MeV
with an RF peak power of
4.4
MW
. The items discussed are the beam dynamics parameters of the module (longitudinal and transverse acceptances), the constructional elements and procedures, the accuracies of the various mechanical elements, the cooling system, the RF tuning, the RF measurement and the RF power tests. These tests showed that, after a short conditioning time, the gradient in each of the four tanks of the module could reach
28.5
MV/m
, much larger than the nominal project value
(15.8
MV/m)
. The last section of the paper describes the successful acceleration tests performed at the Laboratori Nazionali del Sud of INFN in Catania with a solid-state
3
GHz
modulator lent by IBA.
Summary
Background: Metabolic syndrome (MS) prevalence between different populations in obese adolescents is scanty to date.
Objective: To compare the MS prevalence and related risk factors in ...Brazilian and Italian obese adolescents.
Methods: A total of 509 adolescents (110 Brazilian, 399 Italian), aged 15–19 years. Anthropometric characteristics, triglycerides (TG), total, low‐density lipoprotein (LDL)‐, high‐density lipoprotein (HDL)‐cholesterol, fasting plasma glucose (FPG), insulin, homeostasis model assessment of insulin resistance (HOMA‐IR) and blood pressure were measured.
Results: Age, body mass index (BMI) and BMI z‐score were not significantly different between the two subgroups. BMI z‐score, TG, FPG, HOMA‐IR and systolic blood pressure (SBP) were significantly higher in boys than in girls both in Brazilian and Italian adolescents, while HDL‐cholesterol levels were lower in boys than in girls. No significant differences were observed in BMI, LDL and total‐cholesterol and DBP in two genders and groups. Insulin, FPG, HOMA‐IR and TG were significantly higher, while LDL‐cholesterol and SBP were significantly lower in Brazilian than in Italian subjects, both in males and females. HDL and total‐cholesterol and diastolic blood pressure (DBP) were not significantly different between the two subgroups and genders. MS prevalence was higher in Brazilian than in Italian obese boys (34.8 vs. 23.6%, p < 0.001) and girls (15.6 vs. 12.5%, p < 0.01). The most frequently altered parameter was HOMA‐IR both in subjects with MS (100% in Brazilian and 81.8% in Italian) and without MS (42.9% and 11.7%).
Conclusion: Metabolic syndrome represents a worldwide emerging health problem in different ethnical populations, the alterations of the risk factors related to MS (different in their prevalence between different subgroups) being strictly linked to the degree of obesity.
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