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Bergamaschi S.,Universitagrave | Guerra F.,Universitagrave | Interlandi M.,Universitagrave | Rota S.,Universitagrave | And 2 more authors.
21st Italian Symposium on Advanced Database Systems, SEBD 2013 | Year: 2013

Systems translating keyword queries into SQL queries over relational databases are usually referred to in the literature as schema-based approaches. These techniques exploit the information contained in the database schema to build SQL queries that express the intended meaning of the user query. Besides, typically, they perform a preliminary step that associates keywords in the user query with database elements (names of tables, attributes and domain attributes). In this paper, we present a probabilistic approach based on a Hidden Markov Model to provide such mappings. In contrast to most existing techniques, our proposal does not require any a-priori knowledge of the database extension.

Rossin A.,CNR Institute of Chemistry of organometallic Compounds | Di Credico B.,CNR Institute of Chemistry of organometallic Compounds | Giambastiani G.,CNR Institute of Chemistry of organometallic Compounds | Peruzzini M.,CNR Institute of Chemistry of organometallic Compounds | And 6 more authors.
Journal of Materials Chemistry | Year: 2012

The polytopic ligand thiazolidine-2,4-dicarboxylic acid (H2L) has been synthesised on a large scale starting from the naturally occurring amino acid l-cysteine. The (R,R)/(S,R)diastereomeric mixture has been separated into its constituents through selective precipitation of the pure (R,R) isomer from concentrated H2O/MeOH solutions. The enantiomerically pure ligand (H2L-RR) has been reacted with CoCl2·6H 2O under hydrothermal conditions, with the final product being [Co(L-RR)(H2O)·H2O]∞ (1). The obtained coordination polymer is optically pure, and it maintains the chiral information that is present in its building block. Two different kinds of channels are present in the 3D structure of 1: one hydrophobic (with the sulfur atoms of the thiazolidine rings exposed) and the other hydrophilic [with the aquo ligand on Co(ii) exposed, and hosting the crystallization water solvent]. 1 has been characterized through a combination of X-ray diffraction (single-crystal and powder) and spectroscopic (CD, IR, UV-Vis, XANES, EXAFS) techniques. Finally, CO2 adsorption tests conducted at 273 K and (pCO2)max = 920 torr have shown a good carbon dioxide uptake, equal to 4.7 wt%. © 2012 The Royal Society of Chemistry.

Fratoddi I.,University of Rome La Sapienza | Battocchio C.,Third University of Rome | Polzonetti G.,Third University of Rome | Sciubba F.,Universitagrave | And 2 more authors.
European Journal of Inorganic Chemistry | Year: 2011

A porphyrin-bridged bimetallic palladium(II) diphenylacetylide complex and the oligomer with 3-5 repeat units have been prepared and spectroscopically characterized. The porphyrin-bridged Pd complex has been used for the stabilization of gold nanoparticles, thus giving rise to unexpected stable structures with no evidence of covalent bonds between the porphyrin and the gold nanoparticles. The morphology investigated by TEM analysis shows that gold nanoparticles with a mean diameter of about 5 nm have been obtained. UV/Vis spectra reveal the achievement of stabilized gold nanoparticles through the presence of the plasmon resonance at 500 nm together with the absorption features of the porphyrin molecule at 436 and 620 nm (Q band). Photoluminescence spectra exhibit an emission feature centred at 572 nm with a shoulder at 325 nm with no quenching effects. XPS measurements at the Au 4f core level suggest an electronic interaction between the gold atoms of the nanoparticle surface and the porphyrin-based complex; NMR spectroscopic studies indicate that interactions and assemblies also occur that involve the porphyrin rings. Elemental analysis suggests that about 120 tilted porphyrins are physisorbed onto the Au core. A porphyrin-bridged Pd complex was prepared and used for the stabilization of gold nanoparticles (AuNPs). AuNPs with a mean diameter of 5 nm and plasmon resonance at 500 nm were obtained. XPS, NMR spectroscopic and elemental analyses indicate the presence of about 120 tilted porphyrin-based complexes physisorbed onto the Au core, with no evidence of covalent bonds. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

D'Angelo G.,Universitagrave | Di Stefano G.,Universitagrave | Navarra A.,University of Perugia
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

We consider devices equipped with multiple wired or wireless interfaces. By switching among interfaces or by combining the available interfaces, each device might establish several connections. A connection is established when the devices at its endpoints share at least one active interface. Each interface is assumed to require an activation cost. In this paper, we consider the problem of establishing the connections defined by a network G = (V,E) while keeping as low as possible the maximum cost set of active interfaces at the single nodes. Nodes V represent the devices, edges E represent the connections that must be established. We study the problem of minimizing the maximum cost set of active interfaces among the nodes of the network in order to cover all the edges. We prove that the problem is NP-hard for any fixed Δ ≥ 5 and k ≥ 16, with Δ being the maximum degree, and k being the number of different interfaces among the network. We also show that the problem cannot be approximated within Ω (ln Δ). We then provide a general approximation algorithm which guarantees a factor of O((1 + b)ln (Δ)), with b being a parameter depending on the topology of the input graph. Interestingly, b can be bounded by a constant for many graph classes. Other approximation and exact algorithms for special cases are presented. © 2011 Springer-Verlag Berlin Heidelberg.

Pighi C.,University of Verona | Gu T.-L.,Cell Signaling Technology Inc. | Dalai I.,University of Verona | Barbi S.,University of Verona | And 10 more authors.
Cellular Oncology | Year: 2011

Background Mantle cell lymphoma (MCL) is currently an incurable entity, and new therapeutic approaches are needed. We have applied a high-throughput phospho-proteomic technique to MCL cell lines to identify activated pathways and we have then validated our data in both cell lines and tumor tissues. Methods PhosphoScan analysis was performed on MCL cell lines. Results were validated by flow cytometry and western blotting. Functional validation was performed by blocking the most active pathway in MCL cell lines. Results PhosphoScan identified more than 300 tyrosinephosporylated proteins, among which many protein kinases. The most abundant peptides belonged to proteins connected with B-cell receptor (BCR) signaling. Active BCR signaling was demonstrated by flow cytometry in MCL cells and by western blotting in MCL tumor tissues. Blocking BCR signaling by Syk inhibitor piceatannol induced dose/time-dependent apoptosis in MCL cell lines, as well as several modifications in the phosphorylation status of BCR pathway members and a collapse of cyclin D1 protein levels. Conclusion Our data support a pro-survival role of BCR signaling in MCL and suggest that this pathway might be a candidate for therapy. Our findings also suggest that Syk activation patterns might be different in MCL compared to other lymphoma subtypes. © The Author(s) 2011.

Donoli A.,Universitagrave | Bisello A.,Universitagrave | Cardena R.,Universitagrave | Ceccon A.,Universitagrave | And 5 more authors.
Inorganica Chimica Acta | Year: 2011

The electrochemical and near-IR properties of a series of (bis)ferrocenyl complexes, in which the ferrocenyl moieties are spanned by enyne (E)-(-CHCH-C≡C-), diyne (-C≡C-)2, or diene (E)-(-CHCH-)2 C4 unsaturated spacers, were investigated. The experiments performed on 1,4-diferrocenyl-(E)-1-buten-3-yne revealed behaviors indicative of through-bridge/metal-metal electron transfer. The enyne bridged (bis)ferrocenyl cation displays charge transfer properties intermediate between the dienyl and diynyl systems and can be assigned to weakly coupled Class II mixed valence species. The analysis of the collected data according to the classical two-state Hush theory revealed that the efficiency of the electron transfer increases from wholly sp-C to wholly sp2-C bridged complexes. Therefore, the degree of communication is modulated according to the structure of the bridging ligand. © 2011 Elsevier B.V. All rights reserved.

Carletti C.,Marche Polytechnic University | Gasparri A.,Universitagrave | Longhi S.,Marche Polytechnic University | Ulivi G.,Universitagrave
IFAC Proceedings Volumes (IFAC-PapersOnline) | Year: 2011

In this paper the simultaneous roll reduction and course keeping problem for a surface vessel by means of active fins and rudder is addressed. This work extends the results proposed in [Carletti et al. (2010)] by considering an alternative nonlinear multivariable ship dynamics where the wave effects are modeled as forces and moments affecting the system dynamics rather than as disturbances affecting the control inputs. A theoretical analysis of the boundedness of the zero dynamics along with the design of a sliding mode control are proposed. Simulations results are provided to corroborate the theoretical analysis. © 2011 IFAC.

Baiardi F.,Universitagrave | Coro F.,Universitagrave | Tonelli F.,Universitagrave | Sgandurra D.,Imperial College London
Journal of Information Security and Applications | Year: 2014

We present a pair of tools to assess the risk of an ICT system through a scenario-based method. In each scenario, rational threat agents compose attacks against the system to reach some predefined goal. The first tool builds a description of the target system by automatically discovering and classifying the vulnerabilities in its components and the attacks they enable. Starting from this description and from the one of the agents, the other tool applies a Monte Carlo method to simulate step by step each agent and its attacks. By collecting samples on the agent attacks, the number of times they reach a goal and the corresponding impact this tool returns a database to compute statistics to support the assessment. After describing both tools, we exemplify their adoption in the assessment of an industrial control system that supervises a power production plant. © 2014 Elsevier Ltd. All rights reserved.

Poce G.,Universitagrave | Cocozza M.,Universitagrave | Consalvi S.,Universitagrave | Biava M.,Universitagrave
European Journal of Medicinal Chemistry | Year: 2014

Despite enormous efforts have been made in the hunt for new drugs, tuberculosis (TB) still remains the first bacterial cause of mortality worldwide, causing an estimated 8.6 million new cases and 1.3 million deaths in 2012. Multi-drug resistant-TB strains no longer respond to first-line drugs and are inexorably spreading with an estimated 650 000 cases as well as extensively-drug resistant-TB strains, which are resistant to any fluoroquinolone and at least one of the second-line drugs, with 60 000 cases. Thus the discovery and development of new medicines is a major keystone for tuberculosis treatment and control. After decades of dormancy in the field of TB drug development, recent efforts from various groups have generated a promising TB drug pipeline. Several new therapeutic agents are concurrently studied in clinical trials together with much activity in the hittolead and lead optimization stages. In this article we will review the recent advances in TB drug discovery with a special focus on structure activity relationship studies of the most advanced compound classes. © 2014 Elsevier Masson SAS. All rights reserved.

D'Errico C.,Universitagrave | Chaudhuri S.,Universitagrave | Gori L.,Universitagrave | Kumar A.,Universitagrave | And 4 more authors.
AIP Conference Proceedings | Year: 2014

We use ultracold atoms in a quasiperiodic lattice to study two outstanding problems in the physics of disordered systems: a) the anomalous diffusion of a wavepacket in the presence of disorder, interactions and noise; b) the transport of a disordered superfluid. a) Our results show that the subdiffusion, observed when interaction alone is present, can be modelled with a nonlinear diffusion equation and the peculiar shape of the expanding density profiles can be connected to the microscopic nonlinear diffusion coefficients. Also when noise alone is present we can describe the observed normal diffusion dynamics by existing microscopic models. In the unexplored regime in which noise and interaction are combined, instead, we observe an anomalous diffusion, that we model with a generalized diffusion equation, where noise- and interaction-induced contributions add each other. b) We find that an instability appearing at relatively large momenta can be employed to locate the fluid-insulator crossover driven by disorder. By investigating the momentum-dependent transport, we observe a sharp crossover from a weakly dissipative regime to a strongly unstable one at a disorder-dependent critical momentum. The set of critical disorder and interaction strengths for which such critical momentum vanishes, can be identified with the separation between a fluid regime and an insulating one and can be related to the predicted zero-temperature superfluid-Bose glass transition. © 2014 AIP Publishing LLC.

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