Any Lifting of a Trace Coding Is a Word Coding

A trace coding is an injective morphism between two trace monoids. This definition naturally extends the classical notion of word coding between two free monoids. We prove that any lifting of a trace coding is a word coding. More precisely, given a trace codingF, let us choose for any lettera, a representative wordf(a) of the traceF(a). Then, the word morphismfis also a coding. This result positively solves a problem proposed by Ochmański.     

Memory for object location: A span study in children.

The aim of the present study was to analyze the developmental changes in three spatial processes, namely, in positional reconstruction involving the retention of spatial locations per se (Positional encoding task), in the assignment of objects to positions (Object-to-position assignment task), and in the integration of these two (Combined task). A span procedure was used to assess the development of spatial memory in children aged 6, 8, and 10 years tested in these three tasks. The findings of the present study provide developmental spans for each relocation task. Results show an age-dependent improvement in all tasks, suggesting that spatial position is not automatically encoded. The results also show different developmental patterns for the relocation tasks considered, suggesting that spatial memory comprises a number of different component processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Design and optimization of a MEMS electret-based capacitive energy scavenger

In this paper, a method for the design and optimization of an electret-based vibration-to-electric microconverter is presented, using a nonlinear dynamical model of the device. The dynamics of the converter is analyzed in detail, showing the importance of properly accounting for the nonlinearity in the optimization process. A procedure to determine a set of optimization parameters is finally presented.     

Survival of planktonic and sessile Acetobacter cerevisiae

This study was designed to investigate the individual or combined effects of ethanol (4–12%), glucose (10–30%) and acetic acid (0–6%) on survival of planktonic and sessile cells of one strain belonging to the new species Acetobacter cerevisiae isolated from traditional balsamic vinegar. The results confirm that the planktonic cells’ survival was negatively affected by ethanol and by acetic acid; moreover, there was a positive correlation between survival and glucose concentration. On the contrary, biofilm formation was observed only in the absence of acetic acid, which was the most affecting variable on the natural ability of cells to attach and grow on surfaces. The obtained results supply new information about the physiology of a novel Acetobacter species and about its natural capability to develop biofilms so that improved control over balsamic vinegar fermentation could be implemented in the future.     

Radon exchange dynamics in a karst system investigated by radon continuous measurements in water: first results

In 2008 the underground Karst Laboratory of Bossea Cave started research on radon exchange dynamics between bedrock, cave waters (main collector and percolations) and indoor underground atmosphere. Radon air concentrations, normally high, increase more and more during the collector's floods. An explanation of this is a radon-water solubilisation process more effective in flood events, because of a greater rock-water contact surface. Radon is then carried by water into the cave and released into the air. To verify this, continuous measurements of radon concentration are needed not only in the air, but also in the waters of the cave. So a new device for continuous radon monitoring in water was tested, connected to the AlphaGuard radon monitor. For the first 6 months of 2010, for different sections of the cave, the correlations between radon in the air, radon in the waters and the collector's stream flow fluctuations were presented and discussed.     

Dissociation between recency and span: Neuropsychological and experimental evidence.

This article reports dissociations between verbal span and the recency portion of the serial position curve in immediate free recall, in 2 neuropsychological case studies and in 3 experiments with normal participants. Patient A. N. presented with an impaired serial verbal span while showing an intact recency effect. The opposite pattern was observed in patient G. C., who despite a poor recency showed normal span in verbal serial recall tasks. Experiments 1 and 2 showed a recency effect with visually and auditory presented lists and written recall was resistant to the effects of articulatory suppression and of irrelevant speech, but was disrupted by the suffix effect. Experiment 3 showed that in contrast with recency, memory span was affected by articulatory suppression and irrelevant speech during presentation but not by a suffix. These findings are not consistent with the idea that span and recency measure aspects of the same memory system. Moreover, in clinical practice, they should not be used as equivalent alternatives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conforming approximations for Kirchhoff plates and shells

Finite element interpolations of arbitrary polynomial degree which are exactly and minimally C¹ continuous across interelement boundaries are studied. A perspective view of the techniques proposed by other authors is presented and some new possibilities are considered. The problem is discussed with reference to the plate and shell finite element approximations, based on the principle of minimum potential energy. The approach also permits identification of sufficient conditions for guaranteeing full rank of stiffness matrices based on modified principles of potential energy. The results of this analysis can be used to investigate the linear dependencies among nodal variables which also occur in the formulation of other fourth-order problems.     

Antifungal activity of fatty acids and their monoglycerides against Fusarium spp. in a laboratory medium

The antifungal activity of lauric, myristic and palmitic acids and their monoglycerides against fusaria was investigated. Data were modelled through a re-parameterized Gompertz equation and the Minimum Detection Time (MDT), i.e. the time (days) to attain 1 cm colony diameter, was evaluated. Lauric acid exerted a strong bioactivity against moulds; palmitic and myristic acids and their monoglycerides showed a moderate effectiveness and in a reversible manner. The results of this work could be considered quite promising; however, further investigations are proposed to validate these data in foods.     

Metabiotic effects of Fusarium spp. on Escherichia coli O157:H7 and Listeria monocytogenes on raw portioned tomatoes

The metabiotic effects of Fusarium proliferatum, F. avenaceum, and F. oxysporum on Escherichia coli O157:H7 and Listeria monocytogenes in fresh tomatoes were investigated. Tomatoes were preinoculated with the molds and incubated at 15 degrees C for 7 days; then they were inoculated separately with the pathogens, packaged in air and modified atmosphere (5% O2, 30% CO2, and 65% N2), and stored at 4, 8, and 12 degrees C for 9 days. The cell loads of pathogens and lactic acid bacteria and the pH were evaluated periodically. The data were modeled through some different mathematical models to assess the shoulder length, i.e., the time before the beginning of the exponential death phase, the 1-log reduction time (s), and the pathogen death time (deltastand). The preinoculation of tomatoes with the molds enhanced the survival of E. coli O157:H7 by prolonging shoulder length and 8 parameters; this effect, however, was not observed for L. monocytogenes. pH values did not undergo significant changes within the storage time, and the lactic acid bacteria increased from 5 to 7 log CFU/g, without significant differences among the storage temperatures or the packaging atmospheres. The results of this research showed that the use of fresh tomatoes colonized by fusaria (even if the contamination is not visible) could increase significantly the risk of outbreaks due to some pathogens that could be on the surface of fruits and vegetables as a result of cross-contamination at home or incorrect postharvest operations.