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Search Results: 1 - 10 of 401291 matches for " M. Baldoncini "
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Reactor Antineutrinos Signal all over the world
B. Ricci,F. Mantovani,M. Baldoncini,J. Esposito,L. Ludhova,S. Zavatarelli
Physics , 2014,
Abstract: We present an updated estimate of reactor antineutrino signal all over the world, with particular attention to the sites proposed for existing and future geo-neutrino experiment. In our calculation we take into account the most updated data on Thermal Power for each nuclear plant, on reactor antineutrino spectra and on three neutrino oscillation mechanism.
Dissection of Cerebral White Matter. Importance for Neurosurgical Training.
Rubino, Pablo,Baldoncini, Matías,Conesa, Horacio A.
Revista Argentina de Anatomia Online , 2012,
Abstract: The understanding of the three-dimensional architecture of the brain is a fundamental condition to the anatomist and the neurosurgeon, especially during their training in basic or surgical neuroanatomy.Demonstrate through the Klingler’s technique the anatomical three-dimensional disposition of white matter tracts.According to the Klingler’s method (Atlas Cerebri Humani - The inner structure of the brain), is preconized that the material should be fresh. A solution of commercial formalin (5%) and distilled water (95%) should be prepared; the material should be immersed and after the course of 4 weeks immersed in the fixing solution, it should be placed on a tray in the freezer (-10°C) during 8 days. Once removed from the freezer, the material must remain in a formalin 3% solution.We worked with 10 brains prepared as the previously described technique. Our main instruments are: delicate type dissecting Adson forceps without teeth and watchmaker’s forceps, and wooden spatulas with a diameter of 2 and 4 mm.We obtained pieces for the demonstration of various tracts that they are located from the cortex to the depth with a description from the external, medial and basal cerebral aspect.While the dissection of white matter is not a new technique that is used for the study and understanding of the brain, remains extremely useful. The training in this anatomical analysis technique has an essential importance for each neurosurgeon.
A new FSA approach for in situ $γ$-ray spectroscopy
A. Caciolli,M. Baldoncini,G. P. Bezzon,C. Broggini,G. P. Buso,I. Callegari,T. Colonna,G. Fiorentini,E. Guastaldi,F. Mantovani,G. Massa,R. Menegazzo,L. Mou,C. Rossi Alvarez,M. Shyti,A. Zanon,G. Xhixha
Physics , 2011, DOI: 10.1016/j.scitotenv.2011.10.071
Abstract: An increasing demand of environmental radioactivity monitoring comes both from the scientific community and from the society. This requires accurate, reliable and fast response preferably from portable radiation detectors. Thanks to recent improvements in the technology, $\gamma$-spectroscopy with sodium iodide scintillators has been proved to be an excellent tool for in-situ measurements for the identification and quantitative determination of $\gamma$-ray emitting radioisotopes, reducing time and costs. Both for geological and civil purposes not only $^{40}$K, $^{238}$U, and $^{232}$Th have to be measured, but there is also a growing interest to determine the abundances of anthropic elements, like $^{137}$Cs and $^{131}$I, which are used to monitor the effect of nuclear accidents or other human activities. The Full Spectrum Analysis (FSA) approach has been chosen to analyze the $\gamma$-spectra. The Non Negative Least Square (NNLS) and the energy calibration adjustment have been implemented in this method for the first time in order to correct the intrinsic problem related with the $\chi ^2$ minimization which could lead to artifacts and non physical results in the analysis. A new calibration procedure has been developed for the FSA method by using in situ $\gamma$-spectra instead of calibration pad spectra. Finally, the new method has been validated by acquiring $\gamma$-spectra with a 10.16 cm x 10.16 cm sodium iodide detector in 80 different sites in the Ombrone basin, in Tuscany. The results from the FSA method have been compared with the laboratory measurements by using HPGe detectors on soil samples collected in the different sites, showing a satisfactory agreement between them. In particular, the $^{137}$Cs isotopes has been implemented in the analysis since it has been found not negligible during the in-situ measurements.
Relationship between the Recurrent Laryngeal Nerve and the Inferior Thyroid Artery: A Study In Fetal Corpses.
Baldoncini, Matías,Ruiz, Roque Iván,Baetti, Daniel,Ibarzabal, Juan
Revista Argentina de Anatomia Online , 2011,
Abstract: The recurrent laryngeal nerve route is determined by the development and movements of arteries from which ones it is related, and the variations of these structures will set differences in the anatomical disposal of this nerve. After the arterial relation of the recurrent laryngeal nerve near its origin, rises in the neck to reach the intertracheoesofagic space. During this rising road, the recurrent laryngeal nerve crosses to the inferior tiroid artery axially. This works objective is to study on fetus, by means of dissections of the infrahiod area, the conection that the recurrent nerve has with the inferior tiroid artery and analizing some details that can affect this relation.Working with 47 fetus from between 4 and 8 months of gestational age, all preserved with formol to 10 %. We classified the relationship about the position of the inferior laryngeal nerve depending his position regarding to the inferior tiroid artery in: previous position, subsequent and intermediate. Mostly was found the laryngeal recurrent nerve in front of the artery, previous position 48% from the right side and 59 % from the left one. The subsequent position was the second one in order to the frequency in the right side with 30% and in the left at 30% too.
Dry Conservation Techniques for Anatomical Preparations
Mignaco, Roberto,Baetti, Daniel,Ruiz, Roque,Baldoncini, Matías
Revista Argentina de Anatomia Online , 2011,
Study of the vascularization of the Pillars of First Order Heart and its implication on the mechanical complications of acute myocardial infarction. Morphological Analysis in Cadavers.
Baldoncini, Matías,Ruiz, Roque Iván,Simoneta, Francisco,Arabian, Leila
Revista Argentina de Anatomia Online , 2011,
Abstract: The myocardium receives its arterial blood through two arteries, right and left coronary artery. Atherosclerosis is a chronic condition characterized by endothelial damage, followed by accumulation of lymphocytes, macrophages and lipoproteins, among others, between the intima and media layer. One of the secondary complications of myocardial infarction is valvular insufficiency as result of necrosis of the pillars. Our goal is to color the heart vessels, dissect the pillars of the first order and analyze blood supply from its base. It has been worked with 25 human hearts which were infiltrated with differential colors the right coronary artery, anterior descending and circumflex. Then were separated both right and left valvular apparatus. After removing the pillars were severed at its base to analyze the way they were coloring and observe the mode of vascularization.The anterior pillar of the left ventricle in 84% left anterior descending artery and a 16% anterior descending and circumflex artery. The rear pillar 24% right coronary artery, in another 24% were found the three colors used in the tecnic, therefore the three vessels carry blood supply and finally by 52% only for the right coronary and left anterior descending. In the case of the tricuspid valve, anterior pillar in 100% of cases supplied by the right coronary artery and anterior descending artery. The internal pillar of the right ventricle, which vascularized anterior approach 100% by the anterior descending artery and those near the bottom in a 100% right coronary artery. To the rear pillar 72% right coronary artery and 28% clusters vascular Right Coronary Artery and Anterior Descending Artery.
Uranium distribution in the Variscan Basement of Northeastern Sardinia
Xhixha M. Ka?eli,M. Albèri,M. Baldoncini,G. P. Bezzon,G. P. Buso,I. Callegari,L. Casini,S. Cuccuru,G. Fiorentini,E. Guastaldi,F. Mantovani,L. Mou,G. Oggiano,A. Puccini,C. Rossi Alvarez,V. Strati,G. Xhixha,A Zanon
Physics , 2015, DOI: 10.1080/17445647.2015.1115784
Abstract: We present a detailed map of the uranium distribution and its uncertainties in the Variscan Basement of Northeastern Sardinia (VBNS) at a scale 1:100,000. An area of 2100 km2 was investigated by means of 535 data points obtained from laboratory and in situ gamma-ray spectrometry measurements. These data volume corresponds to the highest sampling density of the European Variscides, aimed at studying the genetic processes of the upper crust potentially triggered by an enrichment of radiogenic heat-producing elements. For the first time the Kriging with Variance of Measurement Error method was used to assign weights to the input data which are based on the degree of confidence associated to the measurements obtained with different gamma-ray spectrometry techniques. A detailed tuning of the model parameters for the adopted Experimental Semi-Variogram led to identify a maximum distance of spatial variability coherent to the observed tendency of the experimental data. We demonstrate that the obtained uranium distribution in the VBNS, characterized by several calc-alkaline plutons emplaced within migmatitic massifs and amphibolite-facies metamorphic rocks, is an excellent benchmark for the study of 'hot' collisional chains. The uranium map of VBNS, and in particular the Arzachena minor pluton, confirms the emplacement model based on the recognition of the different petrological associations characterizing the Variscan magmatic processes in the Late Paleozoic. Furthermore, the presented model of the uranium content of the geological bedrock is a potential baseline for future mapping of radon-prone areas.
A multivariate spatial interpolation of airborne γ-ray data using the geological constraints
E. Guastaldi,M. Baldoncini,G. P. Bezzon,C. Broggini,G. P. Buso,A. Caciolli,Carmignani L.,I. Callegari,T. Colonna,K. Dule,G. Fiorentini,M. Ka?eli Xhixha,F. Mantovani,G. Massa,R. Menegazzo,L. Mou,C. Rossi Alvarez,V. Strati,G. Xhixha,A. Zanon
Physics , 2013, DOI: 10.1016/j.rse.2013.05.027
Abstract: In this paper we present maps of K, eU, and eTh abundances of Elba Island (Italy) obtained with a multivariate spatial interpolation of airborne {\gamma}-ray data using the constraints of the geologic map. The radiometric measurements were performed by a module of four NaI(Tl) crystals of 16 L mounted on an autogyro. We applied the collocated cokriging (CCoK) as a multivariate estimation method for interpolating the primary under-sampled airborne {\gamma}-ray data considering the well-sampled geological information as ancillary variables. A random number has been assigned to each of 73 geological formations identified in the geological map at scale 1:10,000. The non-dependency of the estimated results from the random numbering process has been tested for three distinct models. The experimental cross-semivariograms constructed for radioelement-geology couples show well-defined co-variability structures for both direct and crossed variograms. The high statistical correlations among K, eU, and eTh measurements are confirmed also by the same maximum distance of spatial autocorrelation. Combining the smoothing effects of probabilistic interpolator and the abrupt discontinuities of the geological map, the results show a distinct correlation between the geological formation and radioactivity content. The contour of Mt. Capanne pluton can be distinguished by high K, eU and eTh abundances, while different degrees of radioactivity content identify the tectonic units. A clear anomaly of high K content in the Mt. Calamita promontory confirms the presence of felsic dykes and hydrothermal veins not reported in our geological map. Although we assign a unique number to each geological formation, the method shows that the internal variability of the radiometric data is not biased by the multivariate interpolation.
Expected geoneutrino signal at JUNO
Virginia Strati,Marica Baldoncini,Ivan Callegari,Fabio Mantovani,William F. McDonough,Barbara Ricci,Gerti Xhixha
Physics , 2014,
Abstract: Constraints on the Earth's composition and on its radiogenic energy budget come from the detection of geoneutrinos. The KamLAND and Borexino experiments recently reported the geoneutrino flux, which reflects the amount and distribution of U and Th inside the Earth. The KamLAND and Borexino experiments recently reported the geoneutrino flux, which reflects the amount and distribution of U and Th inside the Earth. The JUNO neutrino experiment, designed as a 20 kton liquid scintillator detector, will be built in an underground laboratory in South China about 53 km from the Yangjiang and Taishan nuclear power plants. Given the large detector mass and the intense reactor antineutrino flux, JUNO aims to collect high statistics antineutrino signals from reactors but also to address the challenge of discriminating the geoneutrino signal from the reactor background.The predicted geoneutrino signal at JUNO is 39.7 $^{+6.5}_{-5.2}$ TNU, based on the existing reference Earth model, with the dominant source of uncertainty coming from the modeling of the compositional variability in the local upper crust that surrounds (out to $\sim$ 500 km) the detector. A special focus is dedicated to the 6{\deg} x 4{\deg} Local Crust surrounding the detector which is estimated to contribute for the 44% of the signal. On the base of a worldwide reference model for reactor antineutrinos, the ratio between reactor antineutrino and geoneutrino signals in the geoneutrino energy window is estimated to be 0.7 considering reactors operating in year 2013 and reaches a value of 8.9 by adding the contribution of the future nuclear power plants. In order to extract useful information about the mantle's composition, a refinement of the abundance and distribution of U and Th in the Local Crust is required, with particular attention to the geochemical characterization of the accessible upper crust.
Reference worldwide model for antineutrinos from reactors
Marica Baldoncini,Ivan Callegari,Giovanni Fiorentini,Fabio Mantovani,Barbara Ricci,Virginia Strati,Gerti Xhixha
Physics , 2014, DOI: 10.1103/PhysRevD.91.065002
Abstract: Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth's surface information about natural radioactivity in the whole planet. In this framework we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency (IAEA). We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Borexino), planned (SNO+) and proposed (Juno, RENO-50, LENA and Hanohano) experimental sites. Uncertainties related to reactor antineutrino production, propagation and detection processes are estimated using a Monte Carlo based approach, which provides an overall site dependent uncertainty on the signal in the geoneutrino energy window on the order of 3%. We also implement the off-equilibrium correction to the reference reactor spectra associated with the long-lived isotopes and we estimate a 2.4% increase of the unoscillated event rate in the geoneutrino energy window due to the storage of spent nuclear fuels in the cooling pools. We predict that the research reactors contribute to less than 0.2% to the commercial reactor signal in the investigated 14 sites. We perform a multitemporal analysis of the expected reactor signal over a time lapse of 10 years using reactor operational records collected in a comprehensive database published at www.fe.infn.it/antineutrino.
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