Anticoagulant activities of goby muscle protein hydrolysates

The anticoagulant activities of protein hydrolysates prepared from goby muscle by treatment with various bacterial alkaline proteases were investigated. All proteases exhibited varying degrees of hydrolysis (DH) and all goby protein hydrolysates (GPHs) caused a significant prolongation of both the thrombin time (TT) and the activated partial thromboplastin time (APTT). The hydrolysate generated by the crude protease from Bacillus licheniformis NH1 displayed the highest anticoagulant activity, and the higher TT (about 32 s) at a concentration of 5 mg/mL was obtained with hydrolysate having a DH of 8.86%. This hydrolysate was then fractionated by size exclusion chromatography on a Sephadex G-25 column into five major fractions (F1–F5). Fraction F2, which exhibited the highest anticoagulant activity, was then fractionated by reversed-phase high-performance liquid chromatography. The molecular masses and amino acid sequences of four peptides in peptide sub-fraction F2–6, which exhibited the highest anticoagulant activity, were determined using ESI-MS and ESI-MS/MS, respectively. The structures of these peptides were identified as Leu-Cys-Arg, His-Cys-Phe, Cys-Leu-Cys-Arg and Leu-Cys-Arg-Arg.     

Theoretical and experimental analysis of the behaviour of a photovoltaic pumping system

The aim of the paper is to present the influence of the solar radiation variation on the performances of a stand alone photovoltaic pumping system which consists of photovoltaic generator, dc-dc converter, dc-ac inverter, an immersed group motor-pump and a storage tank that serves a similar purpose to battery storage. Hence a theoretical analysis (modelling and control) of the system is needed. Attention has been paid to the command of the power converters using MPPT and variable laws. The MPPT control allows the extraction of the maximal output power delivered by the PV generator. The inverter ensures the PWM control of the asynchronous motor and a sine wave form of output signals. From the obtained simulation results, we will show that the decrease of the solar radiation degrades performances (the global efficiency and the flow rate) of the PV pumping system. The analysis is validated by simulation and experimental results.     

Optimization of enzymatic extraction of ferulic acid from wheat bran,using response surface methodology,and characterization of the resulting fractions

BACKGROUND: The agro‐industries generate thousands of tons of by‐products, such as bran or pulps, each year. They are, at best, used for cattle feeding. Through biocracking, this biomass may constitute a renewable source for various molecules of interest for the industry. For instance, ferulic acid, a compound showing antioxidant ability, is found in abundance in cereal bran. Its release depends mainly on the breaking of its ester linkage to other constitutive elements of the cell wall, such as arabinoxylans. Response surface methodology was used to evaluate the effects of ferulic acid esterase (FAE) and xylanase activities, as well as incubation time and temperature, on ferulic acid extraction yield from wheat bran. Under optimized conditions, the composition of the hydrolysate and of residual bran were compared to native bran. RESULTS: Experiments carried out under the predicted optimal conditions (FAE amount, 27 U g^?1; xylanase amount, 304 U g^?1; incubation time, 2 h; and temperature, 65 °C) led to an extraction yield of 52.8%, agreeing with the expected value (51.0%). The crude ferulic acid fraction was purified with Amberlite XAD16, leading to a final concentration of 125 µg mL^?1 of ferulic acid in ethanol. The antioxidant capacity of this purified fraction was evaluated by the DPPH· scavenging method: it exhibited better efficiency (EC₅₀ = 10.6 µmol L^?1 in ferulic acid) than the ferulic acid standard (EC₅₀ = 13.7 µmol L^?1). CONCLUSION: These results confirm the potential of wheat bran valorization in the field of natural antioxidant extraction, possibly viable in an industrial scheme. Copyright © 2009 Society of Chemical Industry     

Convergence behavior and root signal sets of stack filters

The four different types of stack filters, type-0 through type-3, are determined by four different shapes of the on-set of the positive Boolean function from which the stack filter is constructed.Under all three appending strategies commonly considered in the literature-first and last value carry-on strategy, constant value carry-on strategy, and the circular approach-stack filters of type-0 through type-2 possess the convergence property, while type-3 stack filters do not all share this property. Examples of cyclic behavior in type-3 stack filters are given. Conditions under which certain operations on stack filters which possess the convergence property produce other filters with this property are provided.In perhaps the most important result in this paper, it is shown that the root signal set of any type-3 stack filter is the intersection of the root sets of the type-1 and type-2 stack filters from which the type-3 filter is constructed. This should simplify the task of finding the set of roots of type-3 stack filters.The rates of convergence for stack filters of type-1 and type-2 are determined for each appending approach. The convergence behavior and rates of convergence of stack filters of type-1 and type-2 are then generalized to include type-1 and type-2 filters with indexi.     

Urban 3D segmentation and modelling from street view images and LiDAR point clouds

3D urban maps with semantic labels and metric information are not only essential for the next generation robots such autonomous vehicles and city drones, but also help to visualize and augment local environment in mobile user applications. The machine vision challenge is to generate accurate urban maps from existing data with minimal manual annotation. In this work, we propose a novel methodology that takes GPS registered LiDAR (Light Detection And Ranging) point clouds and street view images as inputs and creates semantic labels for the 3D points clouds using a hybrid of rule-based parsing and learning-based labelling that combine point cloud and photometric features. The rule-based parsing boosts segmentation of simple and large structures such as street surfaces and building facades that span almost 75% of the point cloud data. For more complex structures, such as cars, trees and pedestrians, we adopt boosted decision trees that exploit both structure (LiDAR) and photometric (street view) features. We provide qualitative examples of our methodology in 3D visualization where we construct parametric graphical models from labelled data and in 2D image segmentation where 3D labels are back projected to the street view images. In quantitative evaluation we report classification accuracy and computing times and compare results to competing methods with three popular databases: NAVTEQ True, Paris-Rue-Madame and TLS (terrestrial laser scanned) Velodyne.     

Endometrium Immunomodulation to Prevent Recurrent Implantation Failure in Assisted Reproductive Technology

After more than four decades of assisted reproductive technology (ART) practice worldwide, today more than 60% of women undergoing in vitro fertilization (IVF) treatments fail to become pregnant after the first embryo transfer and nearly 20% of patients are suffering from unexplained recurrent implantation failures (RIFs) and repeated pregnancy loss (RPL). The literature reported different causes of RIF–RPL, mainly multifactorial, endometrial and idiopathic. RIF remains a black box because of the complicated categorization and causes of this physio-pathological dysregulation of implantation and pregnancy process after ovarian stimulation. Many options were suggested as solutions to treat RIF–RPL with controversial results on their usefulness. In this article, we reviewed different possible therapeutic options to improve implantation rates and clinical outcomes. Based on our experience we believe that endometrium immunomodulation after intrauterine insemination of activated autologous peripheral blood mononuclear cells (PBMCs) or platelet-rich plasma (PRP) can be a promising therapeutic solution. On the other hand, peripheral lymphocyte balance typing, specific cytokines and interleukins profiling can be proposed as predictive biomarkers of implantation before embryo transfer.     

Removal of contaminants and pathogens from secondary effluents using intermittent sand filters

Intermittent infiltration percolation of wastewater through unsaturated sand bed is an extensive treatment technique aimed at eliminating organic matter, oxidizing ammonium and removing pathogens. The main purpose of this study was to determine the depuration efficiencies of a sand filter to remove contaminants from secondary wastewater effluents. Elimination of pathogenic bacteria (total and faecal coliforms, streptococci) and their relationship with the filter depth were investigated. Results showed a high capacity of infiltration percolation process to treat secondary effluents. Total elimination of suspended solids was obtained. Mean removal rate of BOD(5) and COD was more than 97 and more than 81%, respectively. Other water quality parameters such as NH(4)-N, TKN and PO(4)-P showed significant reduction except NO(3)-N which increased significantly in the filtered water. Efficiency of pathogenic bacteria removal was shown to mainly depend on the filter depth. Average reductions of 2.35 log total coliforms, 2.47 log faecal coliforms and 2.11 log faecal streptococci were obtained. The experimental study has shown the influence of the temperature on the output purification of infiltration percolation process.     

Personalized long-term ECG classification: A systematic approach

This paper presents a personalized long-term electrocardiogram (ECG) classification framework, which addresses the problem within a long-term ECG signal, known as Holter register, recorded from an individual patient. Due to the massive amount of ECG beats in a Holter register, visual inspection is quite difficult and cumbersome, if not impossible. Therefore, the proposed system helps professionals to quickly and accurately diagnose any latent heart disease by examining only the representative beats (the so-called master key-beats) each of which is automatically extracted from a time frame of homogeneous (similar) beats. We tested the system on a benchmark database where beats of each Holter register have been manually labeled by cardiologists. The selection of the right master key-beats is the key factor for achieving a highly accurate classification and thus we used exhaustive K-means clustering in order to find out (near-) optimal number of key-beats as well as the master key-beats. The classification process produced results that were consistent with the manual labels with over 99% average accuracy, which basically shows the efficiency and the robustness of the proposed system over massive data (feature) collections in high dimensions.     

Characterization of electromagnetic fields close to microwave devices using electric dipole probes

A methodology to thoroughly characterize an electric near‐field probe based on small dipole antenna is presented. Both theoretical investigations and experimental direct measurements determine the various characteristics of the probe such as selectivity, sensitivity and spatial resolution. Results show the efficiency of the probe for diagnosing electromagnetic phenomena. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.     

Evaluation of the performance of sulfonated esparto grass lignin as a plasticizer-water reducer for cement

The objective of the work described in this first paper of a series is an investigation of the preparation of a sulfonated esparto grass lignin (SEL) and its behavior as a plasticizing-water-reducing agent for cement-water systems. SEL is prepared by extracting the lignin from the black liquor of a soda esparto grass pulping process and then sulfonating it with a mixture of sodium sulfite and formaldehyde.Analyses and characterization of SEL carried out with high-performance size exclusion chromatography (HPSEC), reversed phase chromatography (RPC), infrared spectrometry and chemical methods show that both the molecular weight average and the combined sulfur content are relatively high. Moreover, HPSEC shows that SEL has a relatively more uniform molecular weight distribution (MWD) than the commercial products obtained from the sulfite wood pulping process. On the other hand, SEL could reduce the water content, improve the workability and compressive strength of mortars. SEL also permits a very low rate of slump loss of cements without excessive extension of the final set time.