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BackgroundIn Caucasians, regular consumption of cocoa induces a drop in arterial blood pressure via an increase in nitric oxide (NO) production. However, black individuals have a different NO biodisponibility compared to Caucasians. The aim of this study was to determine, in black Africans, the physiological variations in arterial blood pressure among cocoa consumers.MethodIn total, 49 male black African volunteers, aged between 18 and 30 years old, were randomized into two groups; those consuming 10 g of cocoa powder per day (1,680 mg of flavonoids per day) for 3 weeks (consumer group), and those not consuming cocoa (control group). Systolic (SBP) and diastolic blood pressures (DBP), and heart rate (HR) were measured in the morning on an empty stomach (fasting), on day (D) 1 (without cocoa), D8, D15, and D22. Data were collected by groups and by subgroups established according to the level of SBP, DBP, or HR on D1. The means and variations of the means (between D1 and the subsequent days) of the recorded parameters were calculated and compared between groups and between subgroups.ResultsOn D8, the variations in SBP in the consumer group were significantly different from the control group (−3.72 ± 6.01 versus 0.57 ± 6.66 mmHg; p = 0.02). Between the control and consumer subgroups according to SBP, no statistical difference in the means or variations in SBP was noted. On D8 and D22, the variations in the SBP of consumers with SBP ≥ 110 mmHg on D1 were significantly different from those of other consumers (D8: −6.55 ± 5.96 versus −1.1 ± 4.93 mmHg; p = 0.01; D22: −6.63 ± 7.77 versus 0.35 ± 5.58 mmHg; p = 0.01). In the subgroups with a DBP < 75 mmHg on D1, the mean DBP of the consumers was significantly lower than that of the controls on D8 (65 ± 5 versus 69 ± 6 mmHg; p = 0.03).ConclusionIn young black African men living in Côte d’Ivoire, regular consumption of cocoa resulted in a decrease in SBP and DBP. The decrease in SBP appeared to be greater the higher the baseline SBP was.

This paper describes a spectroscopic approach for hyperspectral imaging of plasmodium falciparum infected human red blood cells (RBCs). We have performed a broad-band hyperspectral microscope which has been used to acquire a number of images in 370 nm to 1100 nm range, from fresh human RBCs infected by plasmodium falciparum. These images have been analyzed using the fast computation of entropies and mutual information for color and multispectral images. This has allowed us to determine the matching set of wavelengths for spectroscopic and morphological studies. Extracted quantitative absorption spectra of parts of parasites are presented. This set of data has also been analysis using the Principal Component Analysis. The calculated data permit us to find out the correlation of all the RGB components of the data sets. The outcome has been interpreted as qualitative spectroscopic information on the trophozoite. These results open up the possibility to classify the biological structures contained by the parasite using hyperspectral imaging.

Aim:This study was to evaluate in vitro anti-fungal activity of aqueous and hydroethanolic from medicinal plants extracts collected in Côte d’Ivoire.Materials and Methods:Plants extracts were prepared by homogenization and separately incorporated to Sabouraud agar using the agar slanted double dilution method. Ketoconazole was used as standards for anti-fungal assay. The anti-fungal tests were performed by sowing 1000 cells of Candida albicans on the previously prepared medium culture. Anti-fungal activity was determined by evaluating anti-fungal parameters values (minimal fungicidal concentrations [MFC] and IC50).Results:The results showed that all extracts possessed anti-fungal activities whose levels vary from plant species to another. Eight of them had a satisfactory anti-candidosic activity and extracts from Terminalia species were the most active. Among them the Terminalia superba extracts generated the strongest activities (MFC = 0.0975 mg/mL). Compared with ketoconazole (MFC = 0.390 mg/mL), the T. superba extracts, aqueous (MFC = 0.195 mg/mL) and hydroethanolic (0.0975 mg/mL) were successively twice and four times more active. The worst anti-fungal activity (MFC = 1600 mg/mL) was obtained with the Guarea cedrata aqueous extract.Conclusion:All medicinal plants extracts produced anti-fungal activities, and T. superba was the most active.

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Plein texte disponible sur http://scialert.net/qredirect.php?doi=ajaps.2011.202.210&linkid=pdfInternational audienceThe aim of this study is to present a high dynamic current control and speed estimation strategy for Permanent Magnet Synchronous Motor (PMSM) drives without a speed transducer. The strategy is based on the exact linearization methodology and Extended Sliding Mode Observer (ESMO) algorithm. The performances of the proposed control strategy are analysed by simulations for a 1.6 kW PMSM. The obtained results show the effectiveness of the proposed robust current control approach and speed observation algorithm under load torque and stator resistance variation

Mathematical morphology can process the binary and grayscale image successfully. This theory cannot be extended to the color image directly. In color space, a vector represents a pixel, so in order to compare vectors, vectoriel orderings must be defined first. This paper addresses the question of the extension of morphological operator to the case of color images. The proposed method used the order by bit mixing to replace the conditional order. Our order is based on a combination of reduced and bit mixing ordering of the underlying data. Additionally it is a total ordering. Since it not only solves the problems of false color generated by the marginal order but also those of multiple extrema generated by reduced order. The performance of the introduced operators is illustrated by means of different applications: color gradients for segmenting, image smoothing (noise suppression) by median filter operator and Laplacian operators. Examples of natural color images and synthetic color images are given. Experimental results show the improvement brought by this new method.

Image segmentation denotes a process for partitioning an image into distinct regions, it plays an important role in interpretation and decision making. A large variety of segmentation methods has been developed; among them, multidimensional histogram methods have been investigated but their implementation stays difficult due to the big size of histograms. We present an original method for segmenting n-D (where n is the number of components in image) images or multidimensional images in an unsupervised way using a fuzzy neighbourhood model. It is based on the hierarchical analysis of full n-D compact histograms integrating a fuzzy connected components labelling algorithm that we have realized in this work. Each peak of the histo- gram constitutes a class kernel, as soon as it encloses a number of pixels greater than or equal to a secondary arbitrary threshold knowing that a first threshold was set to define the degree of binary fuzzy similarity be- tween pixels. The use of a lossless compact n-D histogram allows a drastic reduction of the memory space necessary for coding it. As a consequence, the segmentation can be achieved without reducing the colors population of images in the classification step. It is shown that using n-D compact histograms, instead of 1-D and 2-D ones, leads to better segmentation results. Various images were segmented; the evaluation of the quality of segmentation in supervised and unsupervised of segmentation method proposed compare to the classification method k-means gives better results. It thus highlights the relevance of our approach, which can be used for solving many problems of segmentation