Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Search Results: 1 - 10 of 6662 matches for " Alessandro Giannattasio "
All listed articles are free for downloading (OA Articles)
Page 1 /6662
Display every page Item
Amyand’s hernia in a child with permanent neonatal diabetes due to pancreatic agenesis.
Alessandro Giannattasio,Riccardo Campus,Monica Muraca,Giorgio Lucigrai
Pediatric Reports , 2009, DOI: 10.4081/pr.2009.e6
Abstract: Acute or perforated appendicitis within inguinal hernia is rarely encountered and it is known as Amyand’s hernia. We report on the first case occurring in a 4-year-old boy affected by permanent neonatal diabetes mellitus due to pancreatic agenesis, an extremely rare condition. The initial suspicion of inguinal hernia was confirmed by ultrasound examination of the right inguinal region which revealed omental layers inside a swollen inguinal canal; this finding and the clinical presentation allowed a prompt and appropriate surgical management. The careful evaluation of this patient and early recognition of this unique presentation of appendicitis allowed trans-hernial appendectomy and immediate herniorrhaphy. Ultrasonography played a pivotal role to reach the correct diagnosis and to start a prompt treatment.
Effects of Rotation at Different Channel Orientations on the Flow Field inside a Trailing Edge Internal Cooling Channel
Matteo Pascotto,Alessandro Armellini,Luca Casarsa,Claudio Mucignat,Pietro Giannattasio
International Journal of Rotating Machinery , 2013, DOI: 10.1155/2013/765142
Abstract: The flow field inside a cooling channel for the trailing edge of gas turbine blades has been numerically investigated with the aim to highlight the effects of channel rotation and orientation. A commercial 3D RANS solver including a SST turbulence model has been used to compute the isothermal steady air flow inside both static and rotating passages. Simulations were performed at a Reynolds number equal to 20000, a rotation number (Ro) of 0, 0.23, and 0.46, and channel orientations of , 22.5°, and 45°, extending previous results towards new engine-like working conditions. The numerical results have been carefully validated against experimental data obtained by the same authors for conditions and Ro = 0, 0.23. Rotation effects are shown to alter significantly the flow field inside both inlet and trailing edge regions. These effects are attenuated by an increase of the channel orientation from to 45°. 1. Introduction It is a matter of fact that the adoption of proper cooling techniques is a key factor in the development of high performance and reliable gas turbine engines, since the hot gas temperature can be far above the melting point of the material used to manufacture the engine components. Focusing the attention on the internal cooling of gas turbine blades, the experimental research conducted on laboratory scaled models has played a great role in the engines development, while more recently, the availability of powerful computational tools has allowed a deeper insight into the performance of cooling channels characterized by various cross-section shapes (squared, rectangular, and triangular) and layouts (single pass, double pass). In this regard, significant examples concerning the simulation of cooling channels for nozzle blades, in static conditions, are represented by the works of Ooi et al. [1], Lohàsz et al. [2], Luo et al. [3], Viswanathan and Tafti [4], and Spring et al. [5]. However, the recent adoption of blade profiles with a reduced thickness in the trailing edge (TE) region made the thermal protection of the TE of high pressure turbine blades one of the most challenging issues to deal with [6]. Indeed, thin blade profiles are the best choice for a high aerodynamic efficiency, but they introduce severe constraints to the cooling design. Consequently, the TE internal cooling channels have an high aspect ratio cross-section in order to be easily accommodated in the elongated profile. Jet impingement is often used to increase the heat removal, if the blade thickness allows the realization of multiple cavities as in [7]. On the other side, a
Neonatal diabetes mellitus due to pancreatic agenesis and pervasive developmental disorder
Alessandro Giannattasio, Maria Pintaudi, Maria Mancardi, Francesca Battaglia, Edvige Veneselli, Renata Lorini, Giuseppe d'Annunzio
Italian Journal of Pediatrics , 2009, DOI: 10.1186/1824-7288-35-23
Abstract: Dear Editor,Recent studies suggested a link between type 1 diabetes mellitus and pervasive developmental disorder (PDD) and hypothesized a common autoimmune pathogenesis or shared genetic factors [1]. Confirmation of an association between PDD and type 1 diabetes mellitus is still lacking. On the contrary permanent neonatal diabetes mellitus (PNDM) due to pancreas agenesis is an extremely rare condition, associated with intra-uterine growth retardation (IUGR), cardiac defects, gall bladder or cerebellum agenesis [2]. No association with psychiatric symptoms has been described up to now. We describe a patient with association of PNDM due to pancreatic agenesis, mild mental retardation and PDD. The patient, a boy who is currently aged 6, is the first child of healthy unrelated parents (father from Italy and mother from Spain). He was born at 35 weeks of gestation, with severe IUGR (weight 1620 g, <3rd percentile and length 45 cm, <3rd percentile) [3]. In the first day of life he developed hyperglycemia: neonatal diabetes was diagnosed and treated with insulin, initially intravenously and then subcutaneously. Atrial septal defect was discovered, in absence of other dysmorphic features. Pancreas agenesis was detected by ultrasound, and then confirmed by magnetic resonance imaging (MRI). Pancreatic exocrine insufficiency was treated with enzymes. Glycemic control was characterized during the first two years of life by fluctuations despite strict dietary regimen and frequent variation of insulin dosages. When 3 month-old the child presented a severe episode of hypoglicemia (plasma glucose 30 mg%); intramuscular glucagon was administrated and no neurological damage was evident at subsequent neuroimaging studies. Karyotype was normal and search for Fragile-X Syndrome was negative, as well as genetic testing for the most common forms of neonatal diabetes [4]. Brain MRI and neurophysiologic evaluations (auditory brainstem evoked potential, nerve conduction velocities and elec
Pneumococcal and influenza vaccination rates and their determinants in children with chronic medical conditions
Antonietta Giannattasio, Veronica Squeglia, Andrea Lo Vecchio, Maria Russo, Alessandro Barbarino, Raffaella Carlomagno, Alfredo Guarino
Italian Journal of Pediatrics , 2010, DOI: 10.1186/1824-7288-36-28
Abstract: Children with HIV infection, cystic fibrosis, liver transplantation and diabetes mellitus were enrolled. Physicians of regional Reference Centres for each condition, primary care paediatricians and caregivers of children provided information through specific questionnaires. For diabetes, 3 Reference Centres were included.Less than 25% of children in each group received pneumococcal vaccination. Vaccination rates against influenza were 73% in patients with HIV-infection, 90% in patients with cystic fibrosis, 76% in patients with liver transplantation, and ranged from 21% to 61% in patients with diabetes mellitus. Reference Centres rather than primary care paediatricians had a major role in promoting vaccinations. Lack of information was the main reason for missing vaccination. Awareness of the severity of pneumococcus infection by key informants of at-risk children was associated with higher vaccination rate.Vaccination rates in children with chronic conditions were poor for pneumococcus and slightly better for influenza. Barriers to vaccination include lack of awareness, health care and organization problems.Among vaccine preventable diseases, two are of outstanding importance and provide an interesting area of evaluation: pneumococcus and influenza infections. The first is a relatively common and potentially severe infection for which vaccines are widely available, effective and relatively widespread. Influenza has peculiar features related to variable degree and the need of annual vaccination.Subjects with chronic medical conditions are at increased risk for severe complications related to vaccine-preventable infections and should be extensively immunized [1,2]. Influenza and invasive Streptococcus pneumoniae infections are associated with increased morbidity, hospitalisation and mortality in children with chronic medical conditions compared to healthy children [3-7].Criteria for influenza immunization in USA by Advisory Committee for Immunization Practice (ACIP)
Changing libraries, encountering the law
Isabelle Giannattasio
Liber Quarterly : The Journal of European Research Libraries , 2004,
Abstract: The technical and legal issues associated with digital material, originally the concern principally of audiovisual librarians, now impact upon library management in general. Three factors, occurring simultaneously, have driven the digital agenda for library managers: the high profile accorded to the accomplishment of mission; the ever-increasing complexity of copyright legislation; and the Internet which has served as a catalyst for deregulation and globalisation. The purpose of this short article is to explore both the opportunities and the obstacles posed by these factors across three core areas of digital collection management: conservation, access and development. I shall draw upon the Bibliothèque nationale de France (BnF) in this context. The BnF is a national library containing heritage collections, largely legal deposit and used for research purposes,. and also collections aimed at a far wider public.. The Audiovisual department is in charge of phonograms, videograms, multimedia and electronic documents. The collection was originally created in 1911 by the linguist Ferdinand Brunot of the Sorbonne University as 'Les Archives de la parole'. Subsequently the collection has been further developed mainly with published records, mostly as legal deposit. The collection now has over one million documents, in all kinds of technical devices and carriers. In France, three institutions share the audiovisual heritage collections: the BnF for documents, the Centre National de la Cinématographie (CNC) for film, and the Institut national de l'Audiovisuel for radio and television archives. In the BnF audiovisual collections are enlarged by legal deposit, by acquisitions and by donations. But whereas we own the carriers - a material property -, we do not own the intellectual property in the work. The protection of authors' rights and neighbouring rights are central to the actions we have to perform in order to accomplish our missions of conservation and giving access.
In Type 1 Diabetes a Subset of Anti-Coxsackievirus B4 Antibodies Recognize Autoantigens and Induce Apoptosis of Pancreatic Beta Cells
Caterina Bason, Renata Lorini, Claudio Lunardi, Marzia Dolcino, Alessandro Giannattasio, Giuseppe d’Annunzio, Antonella Rigo, Nicoletta Pedemonte, Roberto Corrocher, Antonio Puccetti
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0057729
Abstract: Type 1 diabetes is characterized by autoimmune destruction of pancreatic beta cells. The role played by autoantibodies directed against beta cells antigens in the pathogenesis of the disease is still unclear. Coxsackievirus B infection has been linked to the onset of type 1 diabetes; however its precise role has not been elucidated yet. To clarify these issues, we screened a random peptide library with sera obtained from 58 patients with recent onset type 1 diabetes, before insulin therapy. We identified an immunodominant peptide recognized by the majority of individual patients’sera, that shares homology with Coxsackievirus B4 VP1 protein and with beta-cell specific autoantigens such as phogrin, phosphofructokinase and voltage-gated L-type calcium channels known to regulate beta cell apoptosis. Antibodies against the peptide affinity-purified from patients’ sera, recognized the viral protein and autoantigens; moreover, such antibodies induced apoptosis of the beta cells upon binding the L-type calcium channels expressed on the beta cell surface, suggesting a calcium dependent mechanism. Our results provide evidence that in autoimmune diabetes a subset of anti-Coxsackievirus antibodies are able to induce apoptosis of pancreatic beta cells which is considered the most critical and final step in the development of autoimmune diabetes without which clinical manifestations do not occur.
Existências em transfigura o: olhares sobre a vadiagem e vidas transgressoras
Gabriel Giannattasio,Rodrigo Poreli
Antíteses , 2008,
Abstract: Este artigo procura investigar e reinterpretarsujeitos singulares que atuaram contra o seutempo, contra os costumes e a moral de suaépoca. As formas outras de readapta o aomundo e encarar a vida através de novaspossibilidades, constituem alguns atos eexpress es de transgress o praticados por taissujeitos. Dá-se destaque à figura do vadio, poisentendemos que sua vida está em constantetransforma o e renova o. Seu vaguear é umacria o e transfigura o da sua própriaexistência.
Non-linear propagation of kink waves to the solar chromosphere
M. Stangalini,F. Giannattasio,S. Jafarzadeh
Physics , 2015, DOI: 10.1051/0004-6361/201425273
Abstract: Small-scale magnetic field concentrations (magnetic elements) in the quiet Sun are believed to contribute to the energy budget of the upper layers of the Sun's atmosphere, as they are observed to support a large number of MHD modes. In recent years, kink waves in magnetic elements were observed at different heights in the solar atmosphere, from the photosphere to the corona. However, the propagation of these waves has not been fully evaluated. Our aim is to investigate the propagation of kink waves in small magnetic elements in the solar atmosphere. We analysed spectropolarimetric data of high-quality and long duration of a photospheric quiet Sun region observed near the disk center with the spectropolarimeter CRISP at the Swedish Solar Telescope (SST), and complemented by simultaneous and co-spatial broad-band chromospheric observations of the same region. Our findings reveal a clear upward propagation of kink waves with frequency above $~2.6$ mHz. Moreover, the signature of a non-linear propagation process is also observed. By comparing photospheric to chromospheric power spectra, no signature of an energy dissipation is found at least at the atmospheric heights at which the data analysed originate. This implies that most of the energy carried by the kink waves (within the frequency range under study $< 17$ mHz) flows to upper layers in the Sun's atmosphere.
Policy Research in a Complex Context  [PDF]
Alessandro Colombo
Intelligent Information Management (IIM) , 2010, DOI: 10.4236/iim.2010.211071
Abstract: Today’s world is characterized by uncertainty and complexity. While examining the importance of research in such a context, the paper attempts to outline a first definition of the role and potential of policy research. The policy process itself has become increasingly complex and non linear, as has its relationship with research. Consequently, policy researchers’ contributions to policymakers may not have a direct, punctual and immediate influence on single issues, but rather a more pervasive, interactive, deliberative effect. Focusing on the theoretical definition of the risk, uncertainty and complexity of the policy process today, the paper outlines some questions and puts forward possible answers which offer a starting point for further analysis. It explores a new role for policy research and underlines the opportunities offered by argumentative, deliberative and multidisciplinary approaches which can positively impact democracy.
VaR-Optimal Risk Management in Regime-Switching Jump-Diffusion Models  [PDF]
Alessandro Ramponi
Journal of Mathematical Finance (JMF) , 2013, DOI: 10.4236/jmf.2013.31009

In this paper we study a classical option-based portfolio strategy which minimizes the Value-at-Risk of the hedged position in a continuous time, regime-switching jump-diffusion market, by using Fourier Transform methods. However, the analysis of this hedging strategy, as well as the computational technique for its implementation, is fairly general, i.e. it can be applied to any dynamical model for which Fourier transform methods are viable.

Page 1 /6662
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.