Semantic distillation: a method for clustering objects by their contextual specificity

Techniques for data-mining, latent semantic analysis, contextual search of databases, etc. have long ago been developed by computer scientists working on information retrieval (IR). Experimental scientists, from all disciplines, having to analyse large collections of raw experimental data (astronomical, physical, biological, etc.) have developed powerful methods for their statistical analysis and for clustering, categorising, and classifying objects. Finally, physicists have developed a theory of quantum measurement, unifying the logical, algebraic, and probabilistic aspects of queries into a single formalism. The purpose of this paper is twofold: first to show that when formulated at an abstract level, problems from IR, from statistical data analysis, and from physical measurement theories are very similar and hence can profitably be cross-fertilised, and, secondly, to propose a novel method of fuzzy hierarchical clustering, termed \textit{semantic distillation} -- strongly inspired from the theory of quantum measurement --, we developed to analyse raw data coming from various types of experiments on DNA arrays. We illustrate the method by analysing DNA arrays experiments and clustering the genes of the array according to their specificity.Comment: Accepted for publication in Studies in Computational Intelligence, Springer-Verla

Moderate conformational impact of citrate on ovotransferrin considerably increases its capacity to self-assemble at the interface

International audienceWe have compared the behavior of ovotransferrin at the air-solution interface in the presence of a monovalention (acetate), or a divalent ion (citrate), the latter being known to induce conformational changesof this protein upon interaction with its iron-binding sites. We have characterised the adsorption layer atthe air–water interface in terms of homogeneity, surface concentration excess and rheological propertiesat pH 4.0. Besides we have investigated the bulk conformation in the presence of the two anions. In thepresence of citrate only, interfacial layers display well-defined domains of higher overall surface concentrationsuggesting multilayers adsorption. Citrate also induces higher helical content and stabilizes theprotein against thermal denaturation. Hence we propose that these changes are involved in the propensityof ovotransferrin to self-assemble at the air–water interface resulting in thick and heterogeneousinterfacial layer

Effect of donkey milk addition on the acceptability of Caprino, a typical goat cheese from Basilicata region, Italy

In this preliminary study we evaluated the effect of different donkeys’ milk additions in cheese making on the acceptability of fresh Caprino, a typical goat cheese produced in a region of southern Italy. In cheese making three batches were considered: A1 only goats’ milk, A2 and A3 with the addition of 5% and 10% of donkeys’ milk, respectively. With the exception of colour, the lowest donkeys’ milk addition improved the acceptability of Caprino cheese. In particular, significant highest ratings (P < 0.05) were observed on odour, flavour, texture and on overall likin

Effect of Guanidium Hydrochloride on the Stability of Horse Skeletal Muscle Myoglobin

The stability of the three dimensional structure of horse skeletal muscle myoglobin was investigated using visible spectroscopy. Guanidium hydrochloride (GuHCl) of concentrations 0.4 – 0.8M have no observable effect on the three dimensional structure as indicated by monitoring the absorbance at 420nm. However, higher concentrations (1.0-3.0M) resulted in unfolding of the protein as indicated by the dip in absorption from 0.535 to 0.350.The requirement for high denaturant concentration to perturb the structure of myoglobin indicates the high stability of the protein. We conclude that high concentrations of the denaturant GuHCl, disrupts the 3-dimensional structure of myoglobin causing its unfolding, in a two- state process, due to weak binding to the protein, which can be studied spectrophotometricall

Изучение пространственной структуры протамина методом временной диэлектрической спектроскопии

Методом временной диэлектрической спектроскопии изучена пространственная структура про­тамина. Показано, что протамины в водных растворах имеют ярко выраженную неглобулярную структуру.Методом часової діелектричної спектроскопії вивчено просто­ рову структуру протаміну. Показано, что протамінам у водних розчинах притаманна яскраво виражена неглобулярна структура.In this work aqueous solution of protamine was investigated using the time domain reflectrometry method. It was shown that in the aqueous solution the conformation of protamine differs from globular proteins conformation