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Search Results: 1 - 10 of 29 matches for " Mariagiovanna Notarangelo "
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Factors influencing the length of the incision and the operating time for total thyroidectomy
Fabrizio Consorti, Francesca Milazzo, Mariagiovanna Notarangelo, Laura Scardella, Alfredo Antonaci
BMC Surgery , 2012, DOI: 10.1186/1471-2482-12-15
Abstract: The aim of the study was to assess the correlation between incision length and operation duration with a set of biometric and clinical factors and establish a rationale for the decision on the length of incision in open surgery.Ninety-seven consecutive patients scheduled for total thyroidectomy were prospectively evaluated. All operations were performed by the same team and the surgeon decided the length of the incision according to his personal judgement. Patients who had previously undergone neck surgery were excluded.The length of the incision was strongly correlated with gender, thyroid volume, neck circumference and clinical diagnosis and weakly correlated with the body mass index. Operation duration was only weakly correlated with gender and neck circumference. Multiple linear regression revealed that the set of factors assessed explained almost 60?% of the variance in incision length but only 20?% of the variance in operation duration. When patients were classified according to the distribution of their thyroid volume, cases within one standard deviation of the mean did not show a significant difference in terms of operation duration with incisions of various lengths.Although thyroid volume was a major factor in driving the decision with respect to the length of the incision, our study shows that it had only minor effect on the duration of the operation. Many more open thyroidectomies could therefore be safely performed with shorter incisions, especially in women. Duration of the operation is probably more closely linked to the inherent technical difficulty of each case.The classical Kocher incision for thyroid surgery, which is approximately 10?cm long, has been the gold standard for more than a century. Since the introduction of Minimally Invasive (MI) surgery of the neck in the second half of the 1990s [1], several different techniques have been proposed, which have been classified as pure endoscopic techniques, video-assisted techniques and minimally inva
Web mapping: tools and solutions for creating interactive maps of forestry interest
Notarangelo G,Alga R
Forest@ , 2011, DOI: 10.3832/efor0678-008
Abstract: The spread of geobrowsers as tools for displaying geographically referenced information provides insights and opportunities to those who, not being specialists in Geographic Information Systems, want to take advantage from exploration and communication power offered by these software. Through the use of web services such as Google Maps and the use of suitable markup languages, one can create interactive maps starting from highly heterogeneous data and information. These interactive maps can also be easily distributed and shared with Internet users, because they do not need to use proprietary software nor special skills but only a web browser. Unlike the maps created with GIS, whose output usually is a static image, the interactive maps retain all their features to users advantage. This paper describes a web application that, using the Keyhole Markup Language and the free service of Google Maps, produces choropleth maps relating to some forest indicators estimated by the last Italian National Forest Inventory. The creation of a map is done through a simple and intuitive interface. The maps created by users can be downloaded as KML file and can be viewed or modified via the freeware application Google Earth or free and open source GIS software like Quantum GIS. The web application is free and available at www.ricercaforestale.it.
XML as a tool to simplify information exchange in forest planning
Fior C,Notarangelo G
Forest@ , 2008, DOI: 10.3832/efor0535-0050222
Abstract: An easy information exchange is essential to face global-scale problems such as a sustainable forest management, global changes or biodiversity protection. A more efficient data integration is especially relevant in Italy, where jurisdiction on forest planning is entrusted to local administrations, such as regions, provinces and mountain communities. Each local administration has independently adopted their own procedures for harvesting inventory information, forcing both technicians and end-users to the use of specific software. This has generated a disarray of procedures and data formats in the field, calling for shared protocols of data exchange. Recently, the increase of information exchange through internet has brought about the adoption of shared protocols for data exchange. XML is one of these protocol that facilitate information exchange among databases and makes data easily accessible to end-users. We developed a specific software called PDA that allows to browse, maintain and search a database of forest management data regardless of the features and the configuration of the end user computer. The software combines a user friendly interface with an efficient data engine.
Non-autonomous Hamiltonian quantum systems, operator equations and representations of Bender-Dunne Weyl ordered basis under time-dependent canonical transformations
Mariagiovanna Gianfreda,Giulio Landolfi
Physics , 2015,
Abstract: We address the problem of integrating operator equations concomitant with the dynamics of non autonomous quantum systems by taking advantage of the use of time-dependent canonical transformations. In particular, we proceed to a discussion in regard to basic examples of one-dimensional non-autonomous dynamical systems enjoying the property that their Hamiltonian can be mapped through a time-dependent linear canonical transformation into an autonomous form, up to a time-dependent multiplicative factor. The operator equations we process essentially reproduce at the quantum level the classical integrability condition for these systems. Operator series form solutions in the Bender-Dunne basis of pseudo-differential operators for one dimensional quantum system are sought for such equations. The derivation of generating functions for the coefficients involved in the \emph{minimal} representation of the series solutions to the operator equations under consideration is particularized. We also provide explicit form of operators that implement arbitrary linear transformations on the Bender-Dunne basis by expressing them in terms of the initial Weyl ordered basis elements. We then remark that the matching of the minimal solutions obtained independently in the two basis, i.e. the basis prior and subsequent the action of canonical linear transformation, is perfectly achieved by retaining only the lowest order contribution in the expression of the transformed Bender-Dunne basis elements.
Biochemical, Antioxidant and Antineoplastic Properties of Italian Saffron (Crocus sativus L.)  [PDF]
Angelo Gismondi, Mariagiovanna Serio, Lorena Canuti, Antonella Canini
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.311190
Abstract: Saffron, the most expensive spice in the world, is got by Crocus sativus L. stigmas. The production of this substance has attracted human interest, since ancient cultures, for its medicinal and culinary properties. Because of saffron high economic value, sometimes, since Middle Ages, it is adulterated with other vegetal materials, dyes or synthetic molecules. Object of this work was the study of one of the best world saffron: Civitaretenga (AQ, Central Italy) C. sativus. Taste, color and aroma of Civitaretenga spice were determined, according to international standards (ISO/Technical Specification 3632), to define its high quality. A biochemical approach was then applied to obtain a secondary metabolite profile of this product. So, crocins, total phenolic content, flavonoids and phenolic acids were detected by HPLC-DAD and spectrophotometric analysis. Moreover, in vitro antioxidant properties and in vivo antineoplastic effects, on highly metastatic murine B16-F10 melanoma cell line, were successfully revealed in Civitaretenga C. sativus extract. All these data confirmed the elevated quality of Civitaretenga saffron and its highly reducing and chemopreventive activity.
Influence of thinnings on wood production in a Turkey oak (Quercus cerris L.) in southern Italy
La Marca O,Notarangelo G
Forest@ , 2009, DOI: 10.3832/efor0581-006
Abstract: The authors report the results of experimental investigations about forest growth, yield and quality of timber assortments, carried out in Turkey oak high forest stands, grown after shelterwood cuttings applied on a wide forest area. The results, obtained after about 20 years of testing, relate to two different intensity of thinning “from below”, compared with areas left to natural evolution. Moreover, some data are reported about the production of litter on a period immediately following the experimental fellings; finally, some comments are made on economic and financial results resulting from intermediate thinnings.
Strong Error Analysis of the $Θ$-Method for Stochastic Hybrid Systems
Martin G. Riedler,Girolama Notarangelo
Mathematics , 2013,
Abstract: We discuss numerical approximation methods for Random Time Change equations which possess a deterministic drift part and jump with state-dependent rates. It is first established that solutions to such equations are versions of certain Piecewise Deterministic Markov Processes. Then we present a convergence theorem establishing strong convergence (convergence in the mean) for semi-implicit Maruyama-type one step methods based on a local error analysis. The family of $\Theta$--Maruyama methods is analysed in detail where the local error is analysed in terms of It{\^o}-Taylor expansions of the exact solution and the approximation process. The study is concluded with numerical experiments that illustrate the theoretical findings.
Nonuniqueness of the C operator in PT-symmetric quantum mechanics
Carl M. Bender,Mariagiovanna Gianfreda
Physics , 2013, DOI: 10.1088/1751-8113/46/27/275306
Abstract: The C operator in PT-symmetric quantum mechanics satisfies a system of three simultaneous algebraic operator equations, $C^2=1$, $[C,PT]=0$, and $[C,H]=0$. These equations are difficult to solve exactly, so perturbative methods have been used in the past to calculate C. The usual approach has been to express the Hamiltonian as $H=H_0+\epsilon H_1$, and to seek a solution for C in the form $C=e^Q P$, where $Q=Q(q,p)$ is odd in the momentum p, even in the coordinate q, and has a perturbation expansion of the form $Q=\epsilon Q_1+\epsilon^3 Q_3+\epsilon^5 Q_5+\ldots$. [In previous work it has always been assumed that the coefficients of even powers of $\epsilon$ in this expansion would be absent because their presence would violate the condition that $Q(p,q)$ is odd in p.] In an earlier paper it was argued that the C operator is not unique because the perturbation coefficient $Q_1$ is nonunique. Here, the nonuniqueness of C is demonstrated at a more fundamental level: It is shown that the perturbation expansion for Q actually has the more general form $Q=Q_0+\epsilon Q_1+\epsilon^2 Q_2+\ldots$ in which {\it all} powers and not just odd powers of $\epsilon$ appear. For the case in which $H_0$ is the harmonic-oscillator Hamiltonian, $Q_0$ is calculated exactly and in closed form and it is shown explicitly to be nonunique. The results are verified by using powerful summation procedures based on analytic continuation. It is also shown how to calculate the higher coefficients in the perturbation series for Q.
Twofold Transition in PT-Symmetric Coupled Oscillators
Carl M. Bender,Mariagiovanna Gianfreda
Physics , 2013, DOI: 10.1103/PhysRevA.88.062111
Abstract: The inspiration for this theoretical paper comes from recent experiments on a PT-symmetric system of two coupled optical whispering galleries (optical resonators). The optical system can be modeled as a pair of coupled linear oscillators, one with gain and the other with loss. If the coupled oscillators have a balanced loss and gain, the system is described by a Hamiltonian and the energy is conserved. This theoretical model exhibits two PT transitions depending on the size of the coupling parameter \epsilon. For small \epsilon the PT symmetry is broken and the system is not in equilibrium, but when \epsilon becomes sufficiently large, the system undergoes a transition to an equilibrium phase in which the PT symmetry is unbroken. For very large \epsilon the system undergoes a second transition and is no longer in equilibrium. The classical and the quantized versions of the system exhibit transitions at exactly the same values of \epsilon.
An exactly solvable $\mathcal{PT}$-symmetric dimer from a Hamiltonian system of nonlinear oscillators with gain and loss
I V Barashenkov,Mariagiovanna Gianfreda
Physics , 2014,
Abstract: We show that a pair of coupled nonlinear oscillators, of which one oscillator has positive and the other one negative damping of equal rate, can form a Hamiltonian system. Small-amplitude oscillations in this system are governed by a $\mathcal{PT}$-symmetric nonlinear Schr\"odinger dimer with linear and cubic coupling. The dimer also represents a Hamiltonian system and is found to be exactly solvable in elementary functions. We show that the nonlinearity softens the $\mathcal{PT}$-symmetry breaking transition in the nonlinearly-coupled dimer: stable periodic and quasiperiodic states with large enough amplitudes persist for an arbitrarily large value of the gain-loss coefficient.
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