Muscle growth in response to changing demands of functions in the teleost Sparus aurata (L.) during development from hatching to juvenile

Growth of laterarl muscle in the teleost fish Sparus aurata (L.) was examined from hatching to juvenile by a basic morphofunctional approach that takes into account structural and ecophysiological aspects and combines in vivo observations and LM and TEM microscopic analysis. As shown in most teleost fishes, muscle growth proceeds by a double mechanism of hyperplasia and hypertrophy that contribute differentially to the overall development of the lateral muscle, giving rise in each myomere to a typical pattern of structurally and functionally different fibre types (slow-red and fast-white fibres, plus pink intermediate fibres) in a nerve-dependent process. During larval life the muscle growth takes place mainly due to hyperplastic growth at the level of specific proliferative zones of the myomeres, from which slow, pink and white muscle fibres are derived. In those species that reach a large adult size a new typical hyperplastic process disseminated throughout the fast white muscle layer takes place during post-larval life. In contrast, hypertrophic growth occurs in all stages, but is the dominant mechanism of muscle growth only in juvenile and adult. The suitable recruitment of the different fibre types enables the fish to optimize its performances according to specific functional and metabolic requirements related to the swimming behaviour and hydrodynamic regimes. The different mechanisms of growth are here analysed in their detailed structural and ultrastructural aspects in order to interpret their adaptive significance in the light of the fish life cycle, with particular reference to locomotion and feeding behaviour.     

Liquid sourdough fermentation: industrial application perspectives

Sourdough fermentation is considered to play a key role to get improved flavour, texture, nutritional and shelf-life properties of bakery products. Since few years Barilla R&D has been focusing on liquid sourdough fermentation which may deserve several advantages with respect to traditional processes. The results showed that the micro-biota of sourdough markedly influences flavour and texture of bakery products. Particular attention has been paid to lactic acid bacteria and yeasts. Selected lactic acid bacteria and yeasts were tested in sourdough liquid fermentation as single strain or in association. The parameters of fermentations were optimized and standardized to set up a laboratory plant liquid fermentation. Only a few strains of lactic acid bacteria were found to be suitable for liquid fermentation alone or in association with yeasts. Fermentations were carried out at pilot plant and an industrial technology was developed. This work describes the results found for the organoleptic profile of an industrial bread started with liquid sourdough with respect to bakers' yeast bread without sourdough addition.     

Simultaneous detection of Escherichia coli O175:H7, Salmonella spp., and Listeria monocytogenes by multiplex PCR

The wide application of nucleic acid amplification techniques and the increasing industrial interest toward rapid methods has led to the development and application of PCR based methods for the detection of microbial pathogens in food. In the present paper we describe the development of a multiplex PCR method for simultaneous detection of Salmonella enterica serovar Typhimurium, Listeria monocytogenes and Escherichia coli O157:H7 in a complex food matrix (liquid whole egg).Four different DNA extraction procedures were evaluated for their application on food and, among these, Chelex resin combined with a DNA purification step were found to better perform on the food system considered.A multiplex PCR system was developed, based on the evaluation and combination of published primer sets, and applied to the simultaneous detection of the target pathogens plus an internal amplification control, both in culture media and in a model food system.The overall system proposed, based on an overnight enrichment step followed by DNA isolation and multiplex PCR, was satisfactorily tested for its specificity and sensitivity and allowed the detection of the presence of bacterial DNA and the identification of the target pathogens down to 10 cells/25 g liquid whole egg.     

New basis functions and computational procedures for p-version finite element analysis

New basis functions and solution procedures for p-version finite element analysis are described. They are used in a highly efficient p-version finite element solver for linear elastostatics and dynamics, which has been used in an industrial environment for over two years. Using two sample applications it is shown that, using the techniques proposed here, p-version finite element analysis can have a substantially lower computational cost, for given accuracy, than standard finite element methods. This makes the industrial applicability of p-version finite element analysis much wider than is commonly believed.     

Using Stochastic State Classes in Quantitative Evaluation of Dense-Time Reactive Systems

In the verification of reactive systems with nondeterministic densely valued temporal parameters, the state-space can be covered through equivalence classes, each composed of a discrete logical location and a dense variety of clock valuations encoded as a difference bounds matrix (DBM). The reachability relation among such classes enables qualitative verification of properties pertaining events ordering and stimulus/response deadlines, but it does not provide any measure of probability for feasible behaviors. We extend DBM equivalence classes with a density-function which provides a measure for the probability of individual states. To this end, we extend time Petri nets by associating a probability density-function to the static firing interval of each nondeterministic transition. We then explain how this stochastic information induces a probability distribution for the states contained within a DBM class and how this probability evolves in the enumeration of the reachability relation among classes. This enables the construction of a stochastic transition system which supports correctness verification based on the theory of TPNs, provides a measure of probability for each feasible run, enables steady-state analysis based on Markov renewal theory. In so doing, we provide a means to identify feasible behaviors and to associate them with a measure of probability in models with multiple concurrent generally distributed nondeterministic timers.     

Remarks and experiments on the construction of respiratory waveforms from electrocardiographic tracings

We report on some observations and preliminary experiments on the deduction of respiratory waveforms from electrocardiographic traces by interpolating the values of angles related to a cardiac electrical axis. The experiments concern comparing the trends obtained from different definitions of the cardiac electrical axis: respiratory waveforms deducted by considering the electrical axis of either the QRS complex or the T wave, and those deducted in the presence of cardiac rhythm disorders, noise, and drifts. The most significant result was obtained when, starting from an ECG trace, we were able to plot curves that were very close to the respiration curve obtained from a belt impedance meter. This result indicates that the objective can be attained. Other results concern specific cases and the constraints to be observed. Among those, arrhythmia, missing beats, pauses, noise, and drifts superimposed on the original ECG traces.