Paul Molin

Water relations of fungal spore germination

SummaryA simple mathematical model, based on the physiology of spore germination of Penicillium roqueforti and Trichoderma viride TS, is proposed and tested to determine germination kinetics of filamentous fungi. The influence of water and of the nature of the solute used to depress the water activity on conidial germination of these two fungi are discussed. The water activity value of the medium is the main factor but the water molar fraction seems to explain certain observed variations in germination kinetics. The best solutes for germination are those which present the greatest deviation from Raoults law.

Multidimensional scaling of emotional responses to music in patients with temporal lobe resection.

The present study investigated emotional responses to music by using multidimensional scaling (MDS) analysis in patients with right or left medial temporal lobe (MTL) lesions and matched normal controls (NC). Participants were required to evaluate emotional dissimilarities of nine musical excerpts that were selected to express graduated changes along the valence and arousal dimensions. For this purpose, they rated dissimilarity between pairs of stimuli on an eight-point scale and the resulting matrices were submitted to an MDS analysis. The results showed that patients did not differ from NC participants in evaluating emotional feelings induced by the musical excerpts, suggesting that all participants were able to distinguish refined emotions. We concluded that the ability to detect and use emotional valence and arousal when making dissimilarity judgments was not strongly impaired by a right or left MTL lesion. This finding has important clinical implications and is discussed in light of current neuropsychological studies on emotion. It suggests that emotional responses to music can be at least partially preserved at a non-verbal level in patients with unilateral temporal lobe damage including the amygdala.

The Hierarchical Agglomerative Clustering with Gower index: a methodology for automatic design of OLAP cube in ecological data processing context

The OLAP systems can be an improvement for ecological studies. In fact, ecology studies, follows and analyzes phenomenon across space and time and according to several parameters. OLAP systems can provide to ecologists browsing in a large dataset. One focus of the current research on OLAP system is the automatic design of OLAP cubes and of data warehouse schemas. This kind of works makes accessible OLAP technology to non information technology experts. But to be efficient, the automatic OLAP building must take into account various cases. Moreover the OLAP technology is based on the concept of hierarchy. Thereby the hierarchical clustering methods are often used by OLAP system designer. In this article, we propose using hierarchical agglomerative clustering with a metric that comes from ecological studies (the Gower similarity index) to build automatically hierarchical dimensions in an OLAP cube. With this similarity index we can perform a hierarchical clustering on heterogeneous datasets that contains qualitative and quantitative variables. We offer a prototypical automatic system which builds dimension for an OLAP cube and we measure the performances of this system according to the number of clustered individuals and according to the number of variables used for clustering. Thanks to these measures we can offer an approximation of performances with a large dataset. Thereby the Gower index in a hierarchical agglomerative clustering permits the management of heterogeneous dataset with missing values in a context of automatic building of OLAP cube. With this methodology, we can build new dimensions based on hierarchies in the data, which are not evident. The data mining methods can complete the expert knowledge during the design of an OLAP cube, because these methods can explain the inherent structure of the data.

The Contribution of Local Features to Familiarity Judgments in Music

The contributions of local and global features to object identification depend upon the context. For example, while local features play an essential role in identification of words and objects, the global features are more influential in face recognition. In order to evaluate the respective strengths of local and global features for face recognition, researchers usually ask participants to recognize human faces (famous or learned) in normal and scrambled pictures. In this paper, we address a similar issue in music. We present the results of an experiment in which musically untrained participants were asked to differentiate famous from unknown musical excerpts that were presented in normal or scrambled ways. Manipulating the size of the temporal window on which the scrambling procedure was applied allowed us to evaluate the minimal length of time necessary for participants to make a familiarity judgment. Quite surprisingly, the minimum duration for differentiation of famous from unknown pieces is extremely short. This finding highlights the contribution of very local features to music memory.

Modeling the heat inactivation of foodborne pathogens in milk powder: High relevance of the substrate water activity

Due to the ability of foodborne pathogens to survive in low moisture foods, the decontamination of these products is an important issue in food hygiene. Up to now, such decontamination has mostly been achieved through empirical methods. The intention of this work is to establish a more rational use of heat treatment cycles. The effects of thermal treatment cycles on the inactivation of dried Salmonella Typhimurium, Salmonella Senftenberg, Cronobacter sakazakii and Escherichia coli were assessed. Bacteria were mixed with whole milk powder and dried down to different water activity levels (0.11, 0.25, 0.44 and 0.58). The rate of inactivated bacteria was determined after thermal treatment at 85°C, 90°C, 95°C and 100°C, from 0s to 180s in closed vessels, in order to maintain aw during treatment. In a first step, logarithmic bacterial inactivation was fitted by means of a classical loglinear model in which temperature and aw have a significant effect (p<0.05). DT,aw values were estimated for each T, aw condition and the results clearly showed that aw is a major parameter in the thermal decontamination of dried foods, a lower aw involving greater thermal resistance. In a second step, Bigelows law was used to determine zT, a classical parameter relative to temperature, and yaw values, a new parameter relative to aw resistance. The values obtained for zT and yaw showed that the bacterium most resistant to temperature variations is Salmonella Typhimurium, while the one most resistant to aw variations is Escherichia coli. These data will help design decontamination protocols or processes in closed batches for low moisture foods.

Escala multidimensional aplicada aos estudos de apreciação musical

The multidimensional scaling (MDS) originates from a set of techniques for analyzing proximity of data, which is obtained through the judgments of participants who concomitantly compare several stimuli in various dimensions. The analysis of proximity judgments produces an analysis in which points represent the relationship existent between stimuli in a Euclidean space. The configuration of stimuli in the space defined by these dimensions permits to make inferences about the underlying perceptual universe of the studied group. Literature reveals that MDS is enlarging the study of music and the measurement of its structural properties.A escala multidimensional (MDS) provem de uma familia de tecnicas de analise de proximidade de dados, obtida por meio do julgamento do participante que compara varios estimulos em varios tracos, concomitantemente. A analise dos julgamentos de proximidade produz um espaco em que pontos representam a relacao entre os estimulos em um espaco euclidiano. O ordenamento dos estimulos ao longo das dimensoes neste espaco permite que inferencias possam ser feitas sobre o universo perceptual subjacente ao grupo de pesquisa. A literatura mostra que a MDS vem ampliando o estudo da musica e a mensuracao de suas propriedades estruturais.

Application of the star-product method to the angular momentum quantization

AbstractWe define a *-product on ℝ3 and solve the polarization equation f*C=0 where C is the Casimir of the coadjoint representation of SO(3). We compute the action of SO(3) on the space of solutions. We then examine the case of non-zero eigenvalues of C, in order to find finite-dimensional representations of SO(3). Finally, we compute

A robust generic method for grid detection in white light microscopy Malassez blade images in the context of cell counting.

\sqrt C *\sqrt C