1,220 research outputs found
Rappresentazione dei mercati locali del lavoro: il sistema di indicatori DOMUS
No full textPer un laureato o un diplomato universitario “presentarsi sul mercato” significa svolgere un’azione di trasparente disponibilità a ricoprire un ruolo professionale. I mercati a cui il laureato può riferirsi sono qualificati sulla base della dimensione territoriale, da quelli attorno a casa, a quelli regionali, e via via fino a quelli nazionali ed internazionali, ma possono essere stratificati anche sulla base delle competenze richieste, sulla base del rischio economico che il laureato è disposto ad assumersi e sulla base di altre variabili ancora. In questo lavoro, tra le tante categorie di mercati del lavoro, si considerano esclusivamente quelli locali. Mercati locali, o sistemi locali, del lavoro sono gli ambiti territoriali minimi entro i quali si connettono la domanda e l’offerta di lavoro
Identification and preliminary characterization of a Ca2+-dependent hemagglutinin in the coelomic fluid of Sipunculus nudus.
No full textA soluble agglutinin was purified by affinity chromatography of the celomic fluid of the marine worm Sipunculus nudus. This agglutinin requires metal cations for its activity and is specific for derivatives of D-galactose. It resulted lightly thermostable, with a pH optimum around 7.5. On SDS-PAGE, it was resolved in two bands, of 33 and 31 kDa in reducing conditions and 29 and 26 kDa in non-reducing conditions. This behavior is probably due to the presence of disulfide bridges between cysteine residues, which are required for the correct functioning of the hemagglutinin, as β-mercaptoethanol completely abolish the agglutinating activity of cell-free celomic fluid. The purified lectin can influence in vitro phagocytosis of yeast by celomic leukocytes: in the presence of the molecule, ingestion of foreign particles results significantly decreased and yeast cells agglutinate and forms rosettes around the celomocytes. This suggests a role of the molecule in immunosurveillance
Bisogni di professionalità nel comparto elettromeccanico ed elettronico veneto
No full textIn questo volume sono descritti i principali risultati di una indagine svolta presso le imprese elettromeccaniche ed elettroniche del Veneto. Nel volume si traggono anche inferenze sulle attività formative dell'Università di Padova nei comparti produttivi in esame
Self-aggregation properties of gangliosides, glycosidic surfactants of biological origin
No full textA comparative study of the aggregation properties of a class of glycosidic surfactants, all having the same hydrophobic part but different saccharidic headgroups, is presented. Although the surfactants, gangliosides, are of biological origin, the reported data can be of general use. Gangliosides are double-tail surfactant like phospholipids, but have a ramified oligosaccharide chain headgroup. They may form either micelles or bilayers depending on the length and conformation of the oligosaccharide chain. For long chains, micelles are formed with a large aggregation number and a long lifetime (many hours), while vesicles are formed for shell sugar chains. Their critical micelle concentration is very low of the order of 10(-8) M, and the micellar dimension is independent of the ionic strength of the solution, even if gangliosides are ionic surfactants due to the presence of sialic acids. Steric effects of the headgroups are very important. For instance the ganglioside GM3 forms vesicles spontaneously in solution with a low bending rigidity of the bilayer. Data are interpreted in terms of the existing geometrical models of self-assembly
Peculiarities in the aggregative behaviour of gangliosides, glucosidic surfactant of biological origin
No full textGlucosidic surfactants play an important role in living matter. An interesting class of them are the gangliosides which have a double-tail hydrophobic part, Like phospholipids, and a ramified oligosaccharide chain as polar head. The large hydrophobic moiety ensures very low CMC values, of the order of 10(-8) M. Phospholipids have a small head group compared with their hydrophobic: part. Therefore they form mainly bilayer-type structures in water. Gangliosides, instead, may form either micelles or bilayers depending on the length and conformation of the oligosaccharide chain. For long chains, micelles are formed with a large aggregation number and a long lifetime (many hours), while vesicles are found for short sugar chains. The presence of a large head group makes vesicle mechanical properties rather peculiar. For instance, the ganglioside GM3, which has the longest sugar chain compatible with bilayer-type structures, forms vesicles spontaneously in solution without supply of external energy. This means that the bending rigidity of the GM3 bilayer is very low, allowing very large thermal undulations. GM3 vesicles, made of a single surfactant, are then found to be in thermodynamic equilibrium with a small amount of large bilayer and multilamellar structures. Frustration of the single-component vesicle system is released if a second amphiphile, of the same type of the ganglioside GM3 but with a larger head group, is added. In this case, spontaneous-curvature readjustements of the two monolayers via demixing can give rise to a spontaneous curvature of the bilayer, energetically favouring vesicles over other structures. It is, in fact, observed experimentally that by adding increasing proportions of GM1 the large aggregates gradually diminish in number, until a pure vesicle solution is obtained for a GM1 to GM3 ratio of 35 to 65
Multiple models for artificial pancreas predictions identified from free-living condition data: A proof of concept study
No full textThe artificial pancreas (AP) is a closed-loop system to automatically regulate the glucose concentration in patients with type 1 diabetes (T1D). Model predictive control (MPC) revealed to be one of the most promising approaches for this control problem. Several MPC algorithms have been tested in clinical trials with satisfactorily results. However, the inter-patient variability characterising T1D patients limits the performance of MPC algorithms synthesized on average models and calls for patient-tailored models. The availability of experimental data on long outpatient trials motivated the study of identification techniques applicable to free-living patient data. Moreover, a detailed data analysis can be used to improve model identification. Considered that the postprandial (PP) glucose control is one of the most critical aspects of glucose regulation, the analysis was focused on the PP period. The intra-day variability is investigated via ANOVA test that highlighted a correlation between PP glucose profiles and different day periods (DPs). A data-driven multiple-model predictor (MMP) based on real-data analysis is proposed in this work. It exploits different identified models on the basis of the knowledge acquired through the data analysis. In particular, the MMP uses three basic models specific of each DP. These models have been identified through the impulse-response technique that achieved promising results in model identification from real-data. The prediction capabilities of the MMP are compared to the performance of a predictor built using a single model identified on a daily subset, showing an improvement in terms of predictions capabilities in the breakfast DP
MIDAW: a web tool for statistical analysis of microarray data
No full textMIDAW (microarray data analysis web tool) is a web interface integrating a series of statistical algorithms that can be used for processing and interpretation of microarray data. MIDAW consists of two main sections: data normalization and data analysis. In the normalization phase the simultaneous processing of several experiments with background correction, global and local mean and variance normalization are carried out. The data analysis section allows graphical display of expression data for descriptive purposes, estimation of missing values, reduction of data dimension, discriminant analysis and identification of marker genes. The statistical results are organized in dynamic web pages and tables, where the transcript/gene probes contained in a specific microarray platform can be linked (according to user choice) to external databases (GenBank, Entrez Gene, UniGene). Tutorial files help the user throughout the statistical analysis to ensure that the forms are filled out correctly. MIDAW has been developed using Perl and PHP and it uses R/Bioconductor languages and routines. MIDAW is GPL licensed and freely accessible at http://muscle.cribi.unipd.it/midaw/. Perl and PHP source codes are available from the authors upon request
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