Types and full abstraction for polyadic π-calculus

A type system for terms of the monadic π-calculus is introduced and used to obtain a full-abstraction result for the translation of the polyadic π-calculus into the monadic calculus: well-sorted terms of the polyadic calculus are barbed congruent iff their translations are typed barbed congruent.     

Text Mining Techniques to Automatically Enrich a Domain Ontology

Though the utility of domain ontologies is now widely acknowledged in the IT (Information Technology) community, several barriers must be overcome before ontologies become practical and useful tools. A critical issue is the ontology construction, i.e., the task of identifying, defining, and entering the concept definitions. In case of large and complex application domains this task can be lengthy, costly, and controversial (since different persons may have different points of view about the same concept). To reduce time, cost (and, sometimes, harsh discussions) it is highly advisable to refer, in constructing or updating an ontology, to the documents available in the field. Text mining tools may be of great help in this task. The work presented in this paper illustrates the guidelines of SymOntos, ontology management system, and the text mining approach adopted herein to support ontology building. The latter operates by extracting, from the related literature, the prominent domain concepts and the semantic relations among them.     

Alias types for “environment-aware” computations

In previous work with Bono we introduced a calculus for modelling “environment-aware” computations, that is computations that adapt their behavior according to the capabilities of the environment. The calculus is an imperative, object-based language (with extensible objects and primitives for discriminating the presence or absence of attributes of objects) equipped with a small-step operational semantics.In this paper we define a type and effect system for the calculus. The typing judgements specify, via constraints, the shape of environments which guarantees the correct execution of expressions and the typing rules track the effect of expression evaluation on the environment. The type and effect system is sound w.r.t. the operational semantics of the language.     

Probabilistic analysis of truss structures with uncertain parameters (virtual distortion method approach)

A new approach for probabilistic characterization of linear elastic redundant trusses with uncertainty on the various members subjected to deterministic loads acting on the nodes of the structure is presented. The method is based on the simple observation that variations of structural parameters are equivalent to superimposed strains on a reference structure depending on the axial forces on the elastic modulus of the original structure as well as on the uncertainty (virtual distortion method approach). Superposition principle may be applied to separate contribution to mechanical response due to external loads and parameter variations. Statically determinate trusses dealt with the proposed method yields explicit analytic solution in terms of displacements while redundant trusses have been studied by means of an asymptotic expansion exhibiting explicit dependence on parameter fluctuations. Probabilistic characterization of the response may then be obtained both for statically determinate and statically indeterminate stochastic trusses.     

Comprehensive two-dimensional normal-phase (adsorption)-reversed-phase liquid chromatography

A comprehensive two-dimensional HPLC system has been developed. It is based on the use of a microbore silica column operated in normal-phase (adsorption) mode (NP) in the first dimension and a monolithic type C18 column operated in reversed-phase (RP) mode in the second dimension. The interface was a 10-port, 2-position valve equipped with two storage loops. The first column was operated at a flow rate of 20 microL/min in isocratic mode, while the monolithic column flow rate was 4 mL/min and was operated in gradient mode. The sample loops had a volume of 20 microL each, and the analysis time in the second dimension was 1 min. In this way, every fraction from the first dimension was transferred on-line to the second dimension switching the automated valve every minute. A photodiode array detector has been used after the secondary column. The use of normal- and reversed-phase mode in the two dimensions can be helpful in the separation of complex mixtures of a natural origin that contain uncharged molecules of comparable dimension, different in polarity and hydrophobicity. The use of a microbore column in the first dimension permits the injection of a small volume in the secondary column, making the transfer of incompatible solvents from the first to the second dimension possible. Since the mobile phase in the NP separation is always stronger than the mobile phase at the head of the secondary column operated in RP mode, the initial eluent strength is important in order to obtain an effective focusing of the sample. The use of a monolithic type column in the second dimension permits the performance of very fast analysis operating at higher flow rates without loss of resolution, due to a higher permeability and increased mass-transfer properties in comparison to conventional particulate columns. Due to the brief reconditioning time necessary for monolithic columns, repetitive gradients can be carried out, extending the field of application to mixtures that contain components with different polarities. The utility of the system has been demonstrated in the analysis of the oxygen heterocyclic fraction of cold-pressed lemon oil, made up of coumarins and psoralens. These components may contain hydroxyl, methoxyl, isopentenyl, isopentenyloxyl, and geranyloxyl groups and oxygen-containing modification of the terpenoid side-chain groups, such as epoxides or vicinal diol groups. The relative location of the components in the 2D plane varied in relation to their chemical structure and allowed positive peak identification. The UV spectra recorded with the photodiode array detector supplied additional information that was used for the characterization of the studied sample.     

Nanocapsules: coating for living cells

One of the most promising tools for future applications in science and medicine is the use of nanotechnologies. Especially self-assembly systems, e.g., polyelectrolyte (PE) capsules prepared by means of the layer-by-layer technique with tailored properties, fulfill the requirements for nano-organized systems in a satisfactory manner. The nano-organized shells are suitable as coating for living cells or artificial tissue to prevent immune response. With these shells, material can be delivered to predefined organs. In this paper, some preliminary results are presented, giving a broad overview over the possibilities to use nano-organized capsules. Based on the observations that the cells while duplicating break the capsule a mutant yeast strain (Saccharomyces cerevisiae), which express GFP-tubulin under galactose promotion, was investigated by means of confocal laser scanning microscopy. The measurements reveal an increased surface charge in the region of buds developed prior encapsulation. In order to test the used PE pair for cytotoxicity, germinating conidia of the fungi Neurospora crassa were coated. The investigation with fluorescence microscopy shows a variation in the surface charge for the growing region and the conidium poles. The capsules exhibit interesting properties as valuable tool in science and a promising candidate for application in the field of medicine.     

Pulmonary fibre burden in sheep living in the Biancavilla area (Sicily): preliminary results

In a national survey on mortality from malignant pleural neoplasms in Italy, aimed at detecting geographic clusters of cases of the disease, the town of Biancavilla, located in a volcanic area of Eastern Sicily, showed high risk of pleural mesothelioma in the absence of occupational asbestos exposure. An environmental survey suggested the stone quarries located in 'Monte Calvario', south-east of the town of Biancavilla, as a possible source of asbestiform fibre exposure. A subsequent crystal-chemistry investigation of the 'Monte Calvario' amphiboles identified the mineral asbestiform fibres as 'fluoro-edenite', a new end-member of the edenite ==> fluoro-edenite series. A collaborative epidemiological and environmental study was initiated to investigate the characteristics of the outbreak of malignant mesothelioma and test the hypothesis of a causal association with exposure to naturally occurring fibres. To investigate if a sheep population could be used to monitor the environmental diffusion of the fibres, we examined lung specimens from 27 culled sheep, at least 3 years old and living near Monte Calvario to check for the presence of fluoro-edenite fibres, using scanning electron microscopy (SEM) analysis and X-ray microanalysis. Fourteen mineral species have been isolated in the mineral particulate matter taken from pulmonary parenchyma, and fluoro-edenite was detected in eight sheep. These preliminary data suggest a possible bio-indicative role of sheep as sentinel animals in the evaluation of environmental fibre diffusion, which merits further investigation.     

TG-DTA, DRIFT and NMR characterisation of humic-like fractions from olive wastes and amended soil

The purpose of the present study is to investigate, by means of thermogravimetric analysis (TG) and differential thermal analysis (DTA), diffuse reflectance infrared Fourier transform (DRIFT) and 2D nuclear magnetic resonance (NMR) spectroscopies, the structural features of the humic-like fraction (HLF) from olive pulp (OP), its effluents originated from the fermentation processes for hydrogen (EH2) and methane production (ECH4) and humic acid (HA) from soil amended with each of these materials. A considerable structural modification emerged between the HLF, in particular from the ECH4 effluent, which was characterised by a high content of polyphenolic and polypeptidic substances. The short-term amendment trial with OP and EH2 indicated that no chemical or structural changes in soil HA appeared. In contrast, the amendment with ECH4 substantially influenced the chemical and structural composition of soil HA. The structural interpretation performed by 2D NMR indicated the presence of aliphatic and aromatic protons while the sugar-like content and O-CH3 groups decreased with respect to the soil control HA. It emerges from this study that olive wastes contain stabilised humic-like material that may be recycled as an amendment in areas where olive trees are cultivated.