6,243 research outputs found
TAPAs: A Tool for the Analysis of Process Algebras
Process algebras are formalisms for modelling concurrent systems that permit mathematical reasoning with respect to a set of desired properties. TAPAs is a tool that can be used to support the use of process algebras to specify and analyze concurrent systems. It does not aim at guaranteeing high performances, but has been developed as a support to teaching. Systems are described as process algebras terms that are then mapped to labelled transition systems (LTSs). Properties are verified either by checking equivalence of concrete and abstract systems descriptions, or by model checking temporal formulae over the obtained LTS. A key feature of TAPAs, that makes it particularly suitable for teaching, is that it maintains a consistent double representation of each system both as a term and as a graph. Another useful didactical feature is the exhibition of counterexamples in case equivalences are not verified or the proposed formulae are not satisfied
Specifying and analysing reputation systems with coordination languages
Reputation systems are nowadays widely used to support decision making in networked systems. Parties in such systems rate each other and use shared ratings to compute reputation scores that drive their interactions. The existence of reputation systems with remarkable differences calls for formal approaches to their analysis. We present a verification methodology for reputation systems that is based on the use of the coordination language Klaim and related analysis tools. First, we define a parametric Klaim specification of a reputation system that can be instantiated with different reputation models. Then, we consider stochastic specification obtained by considering actions with random (exponentially distributed) duration. The resulting specification enables quantitative analysis of properties of the considered system. Feasibility and effectiveness of our proposal is demonstrated by reporting on the analysis of two reputation models
Non-targeted LC-MS based metabolomics analysis of the urinary steroidal profile
The urinary steroidal fraction has been extensively explored as non-invasive alternative to monitor pathological conditions as well as to unveil the illicit intake of pseudo-endogenous anabolic steroids in sport. However, the majority of previous approaches involved the a priori selection of potentially relevant target analytes. Here we describe the non-targeted analysis of the urinary steroidal profiles. The workflow includes minimal sample pretreatment and normalization according to the specific gravity of urine, a 20Â min reverse phase ultra-performance liquid chromatographic separation hyphenated to electrospray time-of-flight mass spectrometry. As initial validation, we analyzed a set of quality control urines spiked with glucurono- and sulfo-conjugated steroids at physiological ranges. We then applied the method for the analysis of samples collected after single transdermal administration of testosterone in hypogonadal men. The method allowed profiling of approximately three thousand metabolic features, including steroids of clinical and forensic relevance. It successfully identified metabolic pathways mostly responsible for groups clustering even in the context of high inter-individual variability and allowed the detection of currently unknown metabolic features correlating with testosterone administration. These outcomes set the stage for future studies aimed at implementing currently monitored urinary steroidal markers both in clinical and forensic analysis
Introduction to morphological and functional evaluation of the heart and coronary arteries
In the last years, the number of clinical indications for the evaluation of the heart â with both computed tomography (CT) and magnetic resonance (MR) â exponentially grew. This evidence reflects the remarkable technological developments of both techniques allowing unprecedented spatial, temporal and contrast resolution levels and to comprehensively evaluate cardiac pathology, combining anatomical information with functional assessment and tissue characterization of myocardial diseases
Right of individual application to the ECtHR: achievements and obstacles
Nella comunicazione si sono messi in evidenza l' "acquis" relativo al diritto di ricorso individuale innanzi alla Corte europea dei diritti dell'uomo (in specie in prospettiva di effettivitĂ ) e le principali zone d'ombra (formalismo della Corte, elevato numero di declaratorie di irricevibilitĂ ecc.
Civil actions for damages caused by war crimes vs. State immunity from jurisdiction and the political act doctrine: ECtHR, ICJ and Italian Courtsââ
Civil actions for war crimes serve the purposes of obtaining a public acknowledgment of the tort and that of reaffirming the legal binding force of the rules protecting fundamental human rights. However, two main obstacles arise before such actions since the defendant is a State: immunity from jurisdiction and the political act doctrine. The interaction between the Italian Supreme Courts (Corte di Cassazione and Corte Costituzionale), the European Court of Human Rights and the International Court of Justice provides clear examples of the achievements and the remaining challenges in this field, where the right of access to a court and the right to an effective remedy should not be excluded in the name of an absolute sovereignty or of an unaccountable raison d'Etat
Super-Hydrophobic Multi-Walled Carbon Nanotube Coatings for Stainless Steel
We have taken advantage of the native surface roughness and the iron content
of AISI 316 stainless steel to direct grow multi-walled carbon nanotube (MWCNT)
random networks by chemical vapor deposition (CVD) at low-temperature (C), without the addition of any external catalysts or
time-consuming pre-treatments. In this way, super-hydrophobic MWCNT films on
stainless steel sheets were obtained, exhibiting high contact angle values
() and high adhesion force (high contact angle hysteresis).
Furthermore, the investigation of MWCNT films at scanning electron microscopy
(SEM) reveals a two-fold hierarchical morphology of the MWCNT random networks
made of hydrophilic carbonaceous nanostructures on the tip of hydrophobic
MWCNTs. Owing to the Salvinia effect, the hydrophobic and hydrophilic composite
surface of the MWCNT films supplies a stationary super-hydrophobic coating for
conductive stainless steel. This biomimetical inspired surface not only may
prevent corrosion and fouling but also could provide low-friction and
drag-reduction.Comment: 6 pages, 3 figure
Exploiting the Hierarchical Morphology of Single-Walled and Multi-Walled Carbon Nanotube Films for Highly Hydrophobic Coatings
Self-assembled hierarchical solid surfaces are very interesting for wetting
phenomena, as observed in a variety of natural and artificial surfaces. Here,
we report single-walled (SWCNT) and multi-walled carbon nanotube (MWCNT) thin
films realized by a simple, rapid, reproducible, and inexpensive filtration
process from an aqueous dispersion, that was deposited at room temperature by a
dry-transfer printing method on glass. Furthermore, the investigation of carbon
nanotube films through scanning electron microscopy (SEM) reveals the
multi-scale hierarchical morphology of the self-assembled carbon nanotube
random networks. Moreover, contact angle measurements show that hierarchical
SWCNT/MWCNT composite surfaces exhibit a higher hydrophobicity (contact angles
of up to 137{\deg}) than bare SWCNT (110{\deg}) and MWCNT (97{\deg}) coatings,
thereby confirming the enhancement produced by the surface hierarchical
morphology.Comment: 7 pages, 5 figures, This article is part of the Thematic Series
"Self-assembly of nanostructures and nanomaterials
Domain-specific queries and Web search personalization: some investigations
Major search engines deploy personalized Web results to enhance users'
experience, by showing them data supposed to be relevant to their interests.
Even if this process may bring benefits to users while browsing, it also raises
concerns on the selection of the search results. In particular, users may be
unknowingly trapped by search engines in protective information bubbles, called
"filter bubbles", which can have the undesired effect of separating users from
information that does not fit their preferences. This paper moves from early
results on quantification of personalization over Google search query results.
Inspired by previous works, we have carried out some experiments consisting of
search queries performed by a battery of Google accounts with differently
prepared profiles. Matching query results, we quantify the level of
personalization, according to topics of the queries and the profile of the
accounts. This work reports initial results and it is a first step a for more
extensive investigation to measure Web search personalization.Comment: In Proceedings WWV 2015, arXiv:1508.0338
On some arthropods associated with Ficus species (Moraceae) in the Maltese Islands
An account is given on the 39 arthropod species which were found on different Ficus trees in the Maltese Islands. Seventeen species represent new records for Malta including Anothopoda fici, Asetadiptacus emiliae, Astichus bachmaieri, Ecphylus caudatus, Empoasca alsiosa, Eupristina verticillata, Ficocyba ficaria, Gynaikothrips ficorum, Josephiella microcarpae, Philotrypesis caricae, Pleistodontes sp., Rhaphitelus maculats, Rhyncaphytoptus ficifoliae, Scobicia chevrieri, Silba adipata, Singhiella citrifolii and Zanchius breviceps. Anothopoda fici and Zanchius breviceps, also represent new records for the entire European territory. Of the 39 arthropods, 33 feed on Ficus trees, whereas the rest are either parasitoids or predators of some of these plant feeders. The 33 species which use Ficus as their host-plant spend most of their development on and utilise the aforementioned trees as their main source of food, at least during their larval development.peer-reviewe
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