169,998 research outputs found
Comparison of EGNOS and Global Maps Vertical TEC in the Southern part of ECAC Region at Range Delay and Position Domain
No full textThis research work provides an overview of the comparison of EGNOS, Global Maps
and experimental data position errors over the Southern part of the ECAC region, on the basis
of TEC values. It is well known that ionospheric conditions represent the main factor that influences
GNSS positioning accuracy at the frequency operation. The satellite signals experience a
delay when passing through the ionosphere. This delay depends on several factors such as
geographical location of the receiver, solar and geomagnetic activity, season and hours of the
day. It results in range errors that can vary from few meters to tens of meters. To overcome
this problem, augmentation system (SBAS) based on geostationary satellites support have
been developed. These systems use a grid-based model to determine the delay introduced by
the ionosphere. Since the delay magnitude depends linearly on the total number of free
electrons in the ionosphere, the delay model corresponds to values of Total Electron Content
(TEC). Performances of such systems are challenged in areas of large ionospheric variability
like those found at low latitude or under space weather events, such as geomagnetic storms.
The European augmentation system is EGNOS. The objective of the present study is to
evaluate on a quantitative level EGNOS performance on both delay (TEC) and positioning
domains by adequate comparisons with independent data and the use of well provided tools
like gLAB
Cinema e giovani
No full textIl capitolo si occupa della relazione tra giovani generazioni e cinema. Dopo aver presentato alcuni dati introduttivi sulla fruizione di spettacoli cinematografici da parte di ragazzi e ragazze, si sottolinea il ruolo del cinema nella produzione di cultura giovanile, in quanto fonte di immagini, narrazioni, modelli comportamentali e fascinazioni utilizzate dagli individui come risorse di riconoscimento e condivisione nella realtà quotidiana. In questi meccanismi culturali è cruciale l’importanza degli attori cinematografici di grande popolarità. I divi, le cui caratteristiche sono mutate più volte nel tempo, sono infatti protagonisti di fenomeni di adorazione sociale da parte di
schiere di fan, per la loro capacità carismatica di farsi oggetti di desideri, fantasie e identificazione. Nella seconda parte del capitolo, il tema della cultura e del consumo mediale giovanile sarà trattato focalizzando l’attenzione sul caso della saga cinematografica di Twilight, ed in particolare sulla fruizione del film Breaking Dawn – part 2. Adottando un approccio etnografico, la ricerca presentata analizza le richieste di riconoscimento e di appartenenza, provenienti dal pubblico giovanile della saga. In quali modi ragazzi e ragazze discutono o commentano ciò che hanno visto? Con chi scelgono di condividere emozioni ed esperienze vissute all’interno dei cinema o reinterpretate alla luce delle esperienze di fruizione? Il cinema si dimostra risorsa sociale che sa attivare processi di identificazione, che produce senso di identità individuale e appartenenza a comunità interpretative
From ESTB to EGNOS: Overview on the Development of the First European Satellite Based Augmentation System
No full textEvoluzione della Tecnologia SISNet nell’ambito dello sviluppo di EGNOS, il primo Sistema di Navigazione Satellitare Europeo
No full textDevelopment and Application of an Experimental Data Server hosting EGNOS and RTCM Correction Data
No full textImpact of random and systematic recall errors and selection bias in case-control studies on mobile phone use and brain tumors in adolescents (CEFALO study)
No full textWhether the use of mobile phones is a risk factor for brain tumors in adolescents is currently being studied. Case-control studies investigating this possible relationship are prone to recall error and selection bias. We assessed the potential impact of random and systematic recall error and selection bias on odds ratios (ORs) by performing simulations based on real data from an ongoing case-control study of mobile phones and brain tumor risk in children and adolescents (CEFALO study). Simulations were conducted for two mobile phone exposure categories: regular and heavy use. Our choice of levels of recall error was guided by a validation study that compared objective network operator data with the self-reported amount of mobile phone use in CEFALO. In our validation study, cases overestimated their number of calls by 9% on average and controls by 34%. Cases also overestimated their duration of calls by 52% on average and controls by 163%. The participation rates in CEFALO were 83% for cases and 71% for controls. In a variety of scenarios, the combined impact of recall error and selection bias on the estimated ORs was complex. These simulations are useful for the interpretation of previous case-control studies on brain tumor and mobile phone use in adults as well as for the interpretation of future studies on adolescents. Bioelectromagnetics (c) 2011 Wiley-Liss, In
Spotlight on ertugliflozin and its potential in the treatment of type 2 diabetes: evidence to date
No full textFrancesca Cinti,* Simona Moffa,* Flavia Impronta,* Chiara MA Cefalo, Vinsin A Sun, Gian Pio Sorice, Teresa Mezza, Andrea Giaccari Center for Endocrine and Metabolic Diseases, Fondazione Policlinico Universitario A Gemelli, Università Cattolica del Sacro Cuore, Rome, Italy *These authors contributed equally to this work Abstract: Sodium-glucose cotransporter 2 (SGLT2) inhibitors are the latest therapeutic strategy in the treatment of type 2 diabetes mellitus (T2DM). Using an insulin-independent mechanism (glycosuria), they reduce glucose toxicity and improve insulin sensitivity and β-cell function. The promising results obtained in clinical trials show that SGLT2 significantly improves glycemic control and provides greater cardiovascular protection, combined with a reduction in body weight and blood pressure (BP). This review focuses on ertugliflozin, a new, highly selective, and reversible SGLT2 inhibitor. Clinical trials published to date show that ertugliflozin, both as a monotherapy and as an add-on to oral antidiabetic agents, is safe and effective in reducing glycosylated hemoglobin (HbA1c), body weight, and BP in T2DM patients. Keywords: antidiabetic drugs, glycosylated hemoglobin, glycemic control, sodium-glucose cotransporter 2 inhibitors, precision medicine, type 1 diabetes mellitus, type 2 diabetes mellitus, weight reduction 
Atopic conditions and brain tumor risk in children and adolescents--an international case-control study (CEFALO)
No full textBACKGROUND
A number of epidemiological studies indicate an inverse association between atopy and brain tumors in adults, particularly gliomas. We investigated the association between atopic disorders and intracranial brain tumors in children and adolescents, using international collaborative CEFALO data.
PATIENTS AND METHODS
CEFALO is a population-based case-control study conducted in Denmark, Norway, Sweden, and Switzerland, including all children and adolescents in the age range 7-19 years diagnosed with a primary brain tumor between 2004 and 2008. Two controls per case were randomly selected from population registers matched on age, sex, and geographic region. Information about atopic conditions and potential confounders was collected through personal interviews.
RESULTS
In total, 352 cases (83%) and 646 controls (71%) participated in the study. For all brain tumors combined, there was no association between ever having had an atopic disorder and brain tumor risk [odds ratio 1.03; 95% confidence interval (CI) 0.70-1.34]. The OR was 0.76 (95% CI 0.53-1.11) for a current atopic condition (in the year before diagnosis) and 1.22 (95% CI 0.86-1.74) for an atopic condition in the past. Similar results were observed for glioma.
CONCLUSIONS
There was no association between atopic conditions and risk of all brain tumors combined or of glioma in particular. Stratification on current or past atopic conditions suggested the possibility of reverse causality, but may also the result of random variation because of small numbers in subgroups. In addition, an ongoing tumor treatment may affect the manifestation of atopic conditions, which could possibly affect recall when reporting about a history of atopic diseases. Only a few studies on atopic conditions and pediatric brain tumors are currently available, and the evidence is conflicting
Numerical approximation of transmission problems across Koch-type highly conductive layers
No full textWe prove a priori error estimates for a parabolic second order transmission problem across a prefractal interface K-n of Koch type which divides a given domain Omega into two non-convex sub-domains Omega(i)(n). By exploiting some regularity results for the solution in Omega(i)(n) we build a suitable mesh, compliant with the so-called "Grisvard" conditions, which allows to achieve an optimal rate of convergence for the semidiscrete approximation of the prefractal problem by Galerkin method. The discretization in time is carried out by the theta-method. (C) 2011 Elsevier Inc. All rights reserved
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