895 research outputs found
An Experimental Platform for the Analysis of Polydisperse Systems Based on Light Scattering and Image Processing
In this work an experimental platform for light scattering analysis has been developed using image sensors, as CCD or CMOS. The main aim of this activity is the investigation of the feasibility of using these types of sensors for polydisperse systems analysis. The second purpose is the implementation of an experimental platform which is enough versatile to permit the observation of different phenomena in order to develop novel sensors/approach using data fusion
Confronto dei contenuti formativi delle scuole di specializzazione dell'area di sanità pubblica: le basi razionali per una proposta di core curriculum per il percorso formativo universitario ex art. 38, D.Lgs 81/2008
E' un confronto dei contenuti formativi delle scuole di specializzazione dell'area di sanità pubblica secondo il nuovo ordinamento al fine della proposta di core curriculum per il percorso formativo universitario ex art. 38, D.Lgs 81/2008 per specializzati in Igiene e Medicina legale, che conseguire i requisiti formativi per la nomina di Medico competente. Nel confronto si ravvisano carenze formative per quanto riguarda il contenuto di valutazione del rischio e prevenzione per gli specializzandi in Medicina legale, mentre carente è il contenuto in approfondimento clinico-diagnostico per gli specializzandi in Igiene. Si propone uno scheda di formazione annuale di percorso universitario
Age-Specific 18F-FDG Image Processing Pipelines and Analysis Are Essential for Individual Mapping of Seizure Foci in Paediatric Patients with Intractable Epilepsy
Fluoro-18-deoxyglucose positron emission tomography (FDG-PET) is an important tool for the pre-surgical assessment of children with drug-resistant epilepsy. Standard assessment is carried out visually and this is often subjective and highly user-dependent. Voxel-wise statistics can be used to remove user-dependent biases by automatically identifying areas of significant hypo/hyper-metabolism, associated to the epileptogenic area. In the clinical settings, this analysis is carried out using commercially available software. These software packages suffer from two main limitations when applied to paediatric PET data: 1) paediatric scans are spatially normalised to an adult standard template and 2) statistical comparisons use an adult control dataset. The aim of this work is to provide a reliable observer-independent pipeline for the analysis of paediatric FDG-PET scans, as part of pre-surgical planning in epilepsy. METHODS: A pseudo-control dataset (n = 19 for 6-9y, n = 93 for 10-20y) was used to create two age-specific FDG-PET paediatric templates in standard paediatric space. The FDG-PET scans of 46 epilepsy patients (n = 16 for 6-9y, n = 30 for 10-17y) were retrospectively collated and analysed using voxel-wise statistics. This was implemented with the standard pipeline available in the commercial software Scenium and an in-house Statistical Parametric Mapping v.8 (SPM8) pipeline (including age-specific paediatric templates and normal database). A kappa test was used to assess the level of agreement between findings of voxel-wise analyses and the clinical diagnosis of each patient. The SPM8 pipeline was further validated using post-surgical seizure-free patients. RESULTS: Improved agreement with the clinical diagnosis was reported using SPM8, in terms of focus localisation, especially for the younger patient group: kScenium=0.489 versus kSPM=0.805. The proposed pipeline also showed a sensitivity of ~70% in both age ranges, for the localisation of hypo-metabolic areas on paediatric FDG-PET scans in post-surgical seizure-free patients. CONCLUSION: We show that by creating age-specific templates and using paediatric control databases, our pipeline provides an accurate and sensitive semi-quantitative method for assessing FDG-PET scans of patients under 18y
Development of a Novel Snom Probe for in Liquid Biological Samples
This work is focused on the study and implementation of a novel method for the development of probes for Scanning Near-field Optical Microscopy (SNOM). The proposed approach is based on the mechanical impedance matching between the optical fiber tip and the resonating tuning fork. This methodology allowed an increase of the quality factor of the piezoelectric resonator used as atomic force transducer in the SNOM probe, thus increasing its overall sensitivity. This kind of probes are often used on biological soft samples in liquid. The presence of water medium has a strong dumping effect on probe sensitivity. Experimental validation of the proposed methodology showed an increase of robustness of SNOM probes also for in liquid samples
Aditivos en la nutrición de peces
The progress of aquaculture and the growing demand for food of animal origin, coupled with concern about food safety for consumers, are causing it to increase the care of animal production, environmental contamination and its complications. Thus, this review was carried out to discuss the principal foundations of the use of additives in fish nutrition. Research is being developed in this direction in different animal species with satisfactory results at all stages of production cycles. This paper presents the results achieved by the use of food additives in the production of fish as ace of performance and health characteristics.El avance de la acuicultura y la creciente demanda de alimentos de origen animal, junto con la preocupación por la seguridad alimentaria de los consumidores, están ocasionando que aumente la atención de la producción ganadera, la contaminación ambiental y sus complicaciones. Por lo tanto, esta revisión se llevó a cabo para discutir los fundamentos esenciales de la utilización de aditivos en la alimentación de peces. La investigación se está llevando a cabo en este sentido en diferentes especies animales con resultados satisfactorios en todas las etapas de los ciclos de producción. Este trabajo presenta los resultados obtenidos por el uso de aditivos alimentarios en la producción de peces en lo relacionado con las características de rendimiento y de salud
Design of beam optics for the Future Circular Collider e+e- -collider rings
A beam optics scheme has been designed for the Future Circular Collider-e+e-
(FCC-ee). The main characteristics of the design are: beam energy 45 to 175
GeV, 100 km circumference with two interaction points (IPs) per ring,
horizontal crossing angle of 30 mrad at the IP and the crab-waist scheme [1]
with local chromaticity correction. The crab-waist scheme is implemented within
the local chromaticity correction system without additional sextupoles, by
reducing the strength of one of the two sextupoles for vertical chromatic
correction at each side of the IP. So-called "tapering" of the magnets is
applied, which scales all fields of the magnets according to the local beam
energy to compensate for the effect of synchrotron radiation (SR) loss along
the ring. An asymmetric layout near the interaction region reduces the critical
energy of SR photons on the incoming side of the IP to values below 100 keV,
while matching the geometry to the beam line of the FCC proton collider
(FCC-hh) [2] as closely as possible. Sufficient transverse/longitudinal dynamic
aperture (DA) has been obtained, including major dynamical effects, to assure
an adequate beam lifetime in the presence of beamstrahlung and top-up
injection. In particular, a momentum acceptance larger than +/-2% has been
obtained, which is better than the momentum acceptance of typical collider
rings by about a factor of 2. The effects of the detector solenoids including
their compensation elements are taken into account as well as synchrotron
radiation in all magnets. The optics presented in this paper is a step toward a
full conceptual design for the collider. A number of issues have been
identified for further study
The FCC-ee study: Progress and challenges
The FCC (Future Circular Collider) study represents a vision for the next
large project in high energy physics, comprising an 80-100 km tunnel that can
house a future 100 TeV hadron collider. The study also includes a high
luminosity e+e- collider operating in the centre-of-mass energy range of 90-350
GeV as a possible intermediate step, the FCC-ee. The FCC-ee aims at definitive
electro-weak precision measurements of the Z, W, H and top particles, and
search for rare phenomena. Although FCC-ee is based on known technology, the
goal performance in luminosity and energy calibration make it quite
challenging. During 2014 the study went through an exploration phase. The study
has now entered its second year and the aim is to produce a conceptual design
report during the next three to four years. We here report on progress since
the last IPAC conference.Comment: Poster presented at IPAC15,Richmond, VA, USA, May 201
Efficient positronium laser excitation for antihydrogen production in a magnetic field
Antihydrogen production by charge exchange reaction between Positronium (Ps)
atoms and antiprotons requires an efficient excitation of Ps atoms up to high-n
levels (Rydberg levels). In this study it is assumed that a Ps cloud is
produced within a relatively strong uniform magnetic field (1 Tesla) and with a
relatively high temperature (100 K). Consequently, the structure of energy
levels are deeply modified by Zeeman and motional Stark effects. A two-step
laser light excitation, the first one from ground to n=3 and the second from
this level to a Rydberg level, is proposed and the physics of the problem is
discussed. We derive a simple formula giving the absorption probability with
substantially incoherent laser pulses. A 30% population deposition in high-
states can be reached with feasible lasers suitably tailored in power and
spectral bandwidth.Comment: 18 pages, 4 figures; changed content (with erasing of section 2),
adding a new figure and new reference
Crab Waist Scheme Luminosity and Background Diagnostic at DAFNE
TUPTPF029International audienceTest of the crab waist scheme, undergoing at the Frascati DAFNE accelerator complex, needs a fast and accurate measurement of the luminosity, as well as a full characterization of the background conditions. Three different monitors, a Bhabha calorimeter, a Bhabha GEM tracker and a gamma bremsstrahlung proportional counter have been designed, tested and installed on the accelerator at the end of January 2008. Results from beam-test measurements, comparison with the Monte Carlo simulation and preliminary data collected during the SIDDHARTA run are presented
- …