62 research outputs found
Comparative performance evaluation of scatternet formation Protocols for networks of Bluetooth devices
No full textThis paper describes the results of the first ns2-based comparative performance evaluation among four major solutions presented in the literature for forming multi-hop networks of Bluetooth devices (scatternet formation). The four protocols considered in this paper are BlueTrees [1], BlueStars [2], BlueNet [3] and the protocol presented in [4] which proposes geometric techniques for topology reduction combined with cluster-based scatternet formation. We implemented the operations of the four protocols from device discovery to scatternet formation. By means of a thorough performance evaluation we have identified protocol parameters and Bluetooth technology features that affect the duration of the formation process and the properties of the produced scatternet. We have investigated how possible modifications of the BT technology (e.g., backoff duration, possibility for a BT inquirer to identify itself) make device discovery more efficient for scatternet formation in multi-hop networks. We have then discussed implementation concerns for each of the selected protocols. Finally, we have analyzed the protocols overhead as well as the effect of the different protocols operations on key metrics of the generated scatternets, which includes the time needed for forming a scatternet, the number of its piconets, the number of slaves per piconet, the number of roles assumed by each node and the scatternet route lengths
Treebanking in the world of Thucydides. Linguistic annotation for the Hellespont Project
No full textThe Hellespont project (DAI, Tufts University) aims to structure the text of a passage from the ancient Greek historian Thucydides (1.89-118), in order to highlight events, persons and peoples that populate the world of the author and connect the different digital sources available for their study. Event annotation in the text in particular requires an in-depth linguistic analysis of morphology, syntax and semantics. However, the available resources for Ancient Greek do not provide adequate standards to support the encoding of semantic and pragmatic phenomena in Ancient Greek texts. In this paper, we discuss the motivation of the project and how we adapted the so called tectogrammatical annotation of the Prague Dependency Treebank to identify the events and describe their structure. The linguistic notion of valency, which is central to tectogrammatical sentence representation, proves very useful for this analysis of Ancient Greek
Erratum: Patients with Severe Obesity during the COVID- 19 Pandemic: How to Maintain an Adequate Multidisciplinary Nutritional Rehabilitation Program? (Obes Facts. (2021) DOI: 10.1159/000513283)
No full textIn the article by De Amicis et al. entitled "Patients with Severe Obesity during the COVID- 19 Pandemic: How to Maintain an Adequate Multidisciplinary Nutritional Rehabilitation Program?" [Obes Facts. 2021, DOI: 10.1159/000513283], the author list is incorrect. The correct author list is: De Amicis R. Cancello R. Capodaglio P. Gobbi M. Brunani A. Gilardini L. Castelnuovo G. Molinari E. Barbieri V. Mambrini S.P. Battezzati A. Bertoli S
Will a Parser Overtake Achilles? First experiments on parsing the Ancient Greek Dependency Treebank
No full textWe present a number of experiments on parsing the Ancient Greek Dependency
Treebank (AGDT), i.e. the largest syntactically annotated corpus of
Ancient Greek currently available (350k words ca). Although the AGDT is
rather unbalanced and far from being representative of all genres and periods
of Ancient Greek, no attempt has been made so far to perform automatic
dependency parsing of Ancient Greek texts. By testing and evaluating one
probabilistic dependency parser (MaltParser), we focus on how to improve
the parsing accuracy and how to customize a feature model that fits the distinctive
properties of Ancient Greek syntax. Also, we prove the impact of
genre and author diversity on parsing performances
BluePleiades a new solution for device discovery and scatternet formation in multi-hop Bluetooth networks
No full textIn this paper we introduce a novel and unified approach to the problems of device discovery and scatternet formation for the Bluetooth standard.We introduce a stochastic model for Bluetooth device discovery and prove that a protocol based on very simple local rules generates a topology that, with high probability, is connected and, crucially, has constant maximum degree. Based on this, we develop a new protocol for device discovery and scatternet formation for multi-hop BlueTooth networks. By means of extensive ns2 simulations we show that our solution is simple to implement, fast and requires low overhead, both for the device discovery and the scatternet formation phases, and leads to better performance when compared to the major approaches so far proposed in the literature
Rare BRCA2 K3326X increases susceptibility to sporadic pancreatic ductal adenocarcinoma: a PANDoRA study.
No full textAbstract
Background: The incredibly poor outlook of pancreatic cancer patients underscores an urgent need for early diagnostic markers. Pancreatic cancer ranks third most-frequent among BRCA1/2-deficient cancers with germline mutations detected in <10% of sporadic cases. Germline variants in breast cancer tumor suppressor BRCA2 have been reported to increase predisposition to several cancers including pancreatic tumors. Rare K3326X (rs11571833, c.9976A>T) which introduces a premature stop codon thus truncating the protein, has previously been implicated in familial PDAC, but not in sporadic cases. A frameshift pathogenic mutation c.6503delTT (rs11571658, p.Leu2092Profs) reported to occur in tandem with K3326X in breast and ovarian cancer
families, has also been speculated to influence risk associations due to linkage disequilibrium between both variants.
Method and results: K3326X was genotyped in 2,969 sporadic cases and 4,700 controls using Taqman chemistry and fidelity of genotypes assessed based on concordance of internal replicates and negative controls. K3326X was observed in 1.2% of cases and 0.8% of controls. Odds ratios (ORs) and associated 95% confidence intervals (CIs) were estimated by multivariate unconditional logistic regression with adjustment for age, sex and region of origin. We also performed a stratified analysis based on age at diagnosis to estimate the risk association between K3326X and early-onset pancreatic cancer. To rule out the likely shared effect of the c.6503delTT mutation on sporadic PDAC risk, we also sequenced DNA from carriers of K3326X in this study. We found K3326X to be associated with increased risk of developing sporadic PDAC ((OR = 1.71, 95% CI = 1.18 - 2.49), P = 0.005). This risk was considerably higher among cases aged 50 years and younger (OR = 2.13, 95% CI = 1.10 - 4.11, P = 0.03). Furthermore, carriers of K3326X did not bear the c.6503delTT mutation thus confirming that the observed risk effect was not influenced by the latter.
Conclusion: These robust associations implicate K3326X in the etiology of sporadic and early-onset PDAC, and therefore warrant replication as well as functional studies to elucidate the role of K3326X in DNA repair mechanisms.
Citation Format: Ofure M. Obazee, Gabriele Capurso, Angelo Andriulli, Pavel Soucek, Ewa Małecka- Panas, Juozas Kupcinskas, Rudolf Kaaks, Maria Gazouli, Thilo Hackert, Aldo Scarpa, Giulia M. Cavestro, Claudio Pasquali, Hermann Brenner, Daniele Campa, Raffaele Pezzilli, Andrea Mambrini, Beatrice Mohelnikova- Duchonova, Ugo Boggi, Jakob Izbicki, Pavel Vodicka, Elzbieta Iskierka-Jazdzewska, Federico Canzian. Rare BRCA2 K3326X increases susceptibility to sporadic pancreatic ductal adenocarcinoma: a PANDoRA study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3411. doi:10.1158/1538-7445.AM2017-3411</jats:p
Linguistica storica, filologia classica e i nuovi orizzonti del NATURAL LANGUAGE PROCESSING
No full textNegli ultimi anni, molte delle metodologie tipiche del Natural Language Processing (Chiari 2007; Jurafsky & Martin 2009) sono state applicate allo studio del greco antico (Papantoniou & Tzitzikas 2020). Nell’ambito della morfologia, ad esempio, ricordiamo la creazione del lemmatizzatore GLEM (Bary et al. 2017). Quest’ultimo usa le parti del discorso per disambiguare parole che potrebbero appartenere allo stesso lemma e, contemporaneamente, è in grado di crearne di nuovi grazie a una componente di apprendimento dotata di memoria ricorsiva.
In ambito sintattico, invece, ricordiamo la creazione dell’Ancient Greek and Latin Dependency Treebank (Bamman e Crane 2011). Questo strumento contiene i testi di Omero, Esiodo, Eschilo e l’Aiace di Sofocle per il greco; e i testi di Cesare, Cicerone, Girolamo, Ovidio, Petronio, Properzio, Sallustio e Virgilio. Di questi testi offre un’analisi morfologica e lessicografica di tipo quantitativo. Lo scopo, dunque, è quello di dare una base empirica, e non più soltanto intuitiva, ai dati filologici.
In questo lavoro vorremmo presentare alcune delle applicazioni di questi nuovi strumenti all’interno della linguistica storica e della filologia classica. Nel primo settore vorremmo ricordare la creazione di corpora annotati, come quello creato da Keersmaekers (2020b) per facilitare l’analisi linguistica dei papiri greci e GLAUx (Keersmaekers 2021). Questo corpus dovrebbe analizzare sedici secoli della storia letteraria greca, prendendo in considerazione diversi generi letterari. Molta attenzione in questo corpus è posta sull’analisi sintattica e su quella dei ruoli semantici dei singoli token (Keersmaekers 2020a).
Accanto ai corpora appena citati, vorremmo presentare in questa sede HoDeL (The Homeric Dependency Lexicon), il quale utilizza l’Ancient Greek and Latin Dependency Treebank come base per creare un lessico annotato di tutti i verbi e i loro argomenti (Zanchi 2021).
Nel settore della filologia, invece, intendiamo evidenziare come i treebank possano diventare un nuovo strumento utile allo studioso per la creazione di un commento o di un’edizione critica di un dato testo (Bamman et al. 2009; Bamman & Crane 2010).
Infine, ci sembra interessante esaminare quegli studi in cui questi nuovi strumenti sono stati usati per risolvere casi dubbi della paternità di un’opera. È il caso, ad esempio, nello studio sugli excerpta di Polibio (Gorman & Gorman 2016), sulla Epistola VII di Platone (Perry 2021) e sul Reso, solitamente attribuito a Euripide (Manousakis & Stamatatos 2018).
Lo scopo del lavoro è quello di sottolineare i vantaggi dell’applicazione del Natural Language Processing sia all’analisi linguistica che a quella filologica, focalizzandoci sulle specificità delle due discipline (Boschetti 2009) e sulle possibilità offerte dalla loro compenetrazione (Gerdes 2013; Mambrini 2016)
Dark matter and global symmetries
No full textAbstractGeneral considerations in general relativity and quantum mechanics are known to potentially rule out continuous global symmetries in the context of any consistent theory of quantum gravity. Assuming the validity of such considerations, we derive stringent bounds from gamma-ray, X-ray, cosmic-ray, neutrino, and CMB data on models that invoke global symmetries to stabilize the dark matter particle. We compute up-to-date, robust model-independent limits on the dark matter lifetime for a variety of Planck-scale suppressed dimension-five effective operators. We then specialize our analysis and apply our bounds to specific models including the Two-Higgs-Doublet, Left–Right, Singlet Fermionic, Zee–Babu, 3-3-1 and Radiative See-Saw models. Assuming that (i) global symmetries are broken at the Planck scale, that (ii) the non-renormalizable operators mediating dark matter decay have O(1) couplings, that (iii) the dark matter is a singlet field, and that (iv) the dark matter density distribution is well described by a NFW profile, we are able to rule out fermionic, vector, and scalar dark matter candidates across a broad mass range (keV–TeV), including the WIMP regime
Blue Pleiades, a new solution for device discovery and scatternet formation in multihop Bluetooth networks, WINET
No full text1 Introduction The Bluetooth (BT) technology, as described in the Specifications of the Bluetooth System Version 1.1 is one of the most promising enabling technologies for pervasive and ubiquitous computing. In this paper we provide basic results to the fundamental problems of device discovery and scatternet formation, i.e. on how Bluetooth nodes can become aware of their neighbors (device discovery), can partition themselves into groups, called piconets, and finally on how such groups can be joined together to form a connected multi-hop ad hoc network, the so-called scatternet. To describe our contribution we first review the two main unsolved problems in this context. A more thorough discussion of the existing literature is deferred to the next section
Association of genetic polymorphisms with survival of pancreatic ductal adenocarcinoma patients
No full textGermline genetic variability might contribute, at least partially, to the survival of pancreatic ductal adenocarcinoma (PDAC) patients. Two recently performed genome-wide association studies (GWAS) on PDAC overall survival (OS) suggested (P < 10-5) the association between 30 genomic regions and PDAC OS. With the aim to highlight the true associations within these regions, we analyzed 44 single-nucleotide polymorphisms (SNPs) in the 30 candidate regions in 1722 PDAC patients within the PANcreatic Disease ReseArch (PANDoRA) consortium. We observed statistically significant associations for five of the selected regions. One association in the CTNNA2 gene on chromosome 2p12 [rs1567532, hazard ratio (HR) = 1.75, 95% confidence interval (CI) 1.19-2.58, P = 0.005 for homozygotes for the minor allele] and one in the last intron of the RUNX2 gene on chromosome 6p21 (rs12209785, HR = 0.88, 95% CI 0.80-0.98, P = 0.014 for heterozygotes) are of particular relevance. These loci do not coincide with those that showed the strongest associations in the previous GWAS. In silico analysis strongly suggested a possible mechanistic link between these two SNPs and pancreatic cancer survival. Functional studies are warranted to confirm the link between these genes (or other genes mapping in those regions) and PDAC prognosis in order to understand whether these variants may have the potential to impact treatment decisions and design of clinical trials
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