1,721,037 research outputs found
Feasibility study of a computer-assisted radioguided surgery system
No full textThis paper deals with the study of a system prototype that can be used as an auxiliary tool in radioguided surgery methods. The use of new technologies in radioguided surgery concern the exact positioning of the lesion to be exerted. This is possible, in operation theatre, thanks to portable scintigraphics devices or to radiation counters. Due to lack of a coordinate system in the operation field, it is difficult for the surgeon to localize the pathology after removing the detection instrument. The system proposed in this paper is composed mainly of three elements: a handheld, high-resolution gamma camera with a small Field Of View (FOV) based on Hamamatsu R8900-00-C12 Position Sensitive Photomultiplier Tube (PSPMT), a laser scanner for the reconstruction of the body district and a stereoscopic system for contactless surgical tool tracking. Analyzing a set of scintigraphic images, taken from different projections, it is possible to localize the three-dimensional position of the lesion. Thanks to the use of the scanner and image fusion techniques, the pathology is shown on a PC monitor correctly positioned with respect to the body surface. Using a couple of stereoscopic cameras, the surgical tool can be tracked and shown on the same monitor, so that the surgeon can know the instantaneous relative position between the tool and the pathology. Exploiting these systems, a navigation system prototype has been developed that is suitable for radioguided surgical application. (c) 2007 Elsevier B.V. All rights reserved
ORGAN DOSES IN MATHEMATICAL PHANTOMS WITH DIFFERENT ELEMENTAL COMPOSITION OF ORGANS AND TISSUES
No full textBrevetto Titolarità CNR “Dispositivo scintigrafico con collimazione variabile”
No full textEstensione US ed EU; EU pendin
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Super Spatial Resolution (SSR) method for scintigraphic imaging
No full textSuper SpatialResolution(SSR)methodforscintigraphicimaging
G. Trinci a,b, R.Massari a,b, M.Scandellari a, F.Scopinaro c, A.Soluri a,b,n
a Institute ofBiomedicalEngineering,CNR,Rome,Italy
b Li-tech S.p.A.,Monterotndo,Rome,Italy
c Nuclear Medicine,‘‘Sapienza’’UniversityofRome,Italy
a r t i c l e info
Article history:
Received 26May2010
Received inrevisedform
14 October2010
Accepted 17October2010
Keywords::
Nuclear medicineimaging
Super SpatialResolution
Spatial Resolution
High ResolutionGammaCamera
Position SensitivePhotomultiplierTube
a b s t r a c t
This workdescribesaninnovativepatentedSuperSpatialResolution(SSR)methodappliedto
scintigraphicdevices.TheaimofSuperResolution(SR)techniquesistoenhancetheresolutionofan
imagingsystem,usinginformationfromseveralimages.SRreconstructionmaybeconsideredasasecond
generationproblemofImageRestoration.ItcombinesseveralslightlydifferentLowResolution(LR)
images toobtainaHighResolution(HR)image.SRtechniquesare,widely,describedinscientificliterature
mainlyforapplicationsinvideocommunication,objectrecognitionandimagecompression.
In thispaperwefocustoapplytheSRtasktothescintigraphicimaging.Specifically,itisdescribedasa
patentedmethodthatusesaHighResolutionScintigraphicCamera(HRSC)tocollectandprocessasetof
scintigraphicimages,inviewofobtainingaveryhighresolutionimage.
The HRSCdevice,whichiscurrentlyusedinMedicalImaging,isbasedonaparallelsquareholes
collimatorandonaHamamatsuH8500PositionSensitivePhotomultiplierTubes(PSPMT).
The SSRmethodisappliedtothesyntheticimagesofthreedifferentphantoms,toverifytheeffective
spatialresolutionvalues.Theresultsconfirmthatitispossibletoachieveoptimalspatialresolutionvalues
at differentdepths,usefulinsmallobjectandsmallanimalimaging.
Our studyconfirmsthefeasibilityofaveryhighresolutionsysteminscintigraphicimagingandthe
possibilitytohavegammacamerasusingtheSSRmethod,toperformclinicalapplicationsonpatients.
& 2010 ElsevierB.V.Allrightsreserve
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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