Effects of Extraction Solvents and Provenances on Phenolic Contents and Antioxidant Activities of Cumin (Cuminum cyminum L.) Seeds

Polyphenol contents and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging activity of cumin (Cuminum cyminum L.) seed extracts were compared depending on their geographical origin (Tunisia and India: TCS and ICS, respectively) and the extraction solvent polarity. The ??-carotene bleaching assay, the chelating ability and the reducing power of the most promising solvent extracts were also assessed. In addition, TCS and ICS extracts were acid-hydrolyzed and the phenolics identified by reversed-phase high-performance liquid chromatography (HPLC). Seed phenolic contents and antioxidant activity appeared to be accession and solvent dependent. Extraction with 80% acetone led to the highest polyphenol (18.60 and 16.50?mg gallic acid equivalents (GAE)/g dry weight (DW)), flavonoid (5.91 and 4.99?mg catechin equivalents (CE)/g DW) and tannin (83.23 and 80.23?mg CE/g DW) contents, respectively for TCS and ICS. DPPH scavenging activity, ??-carotene bleaching assay, chelating ability and reducing power were maximal in 80% acetone for both TCS and ICS. HPLC analysis revealed several phenolic compounds in C. cyminum seeds, with p-coumaric (4.83 and 2.33?mg/g DW), trans-2-dihydrocinnamic (1.09 and 1.20?mg/g DW) and rosmarinic (0.70 and 1.04?mg/g DW) acids as major phenolics in TCS and ICS, respectively. Thus, phenolic composition of cumin seeds is also origin dependent. Taken together, our findings indicate that cumin might constitute a rich and novel source of natural antioxidants as food additives in food industry and that acetone 80% would be the most appropriate solvent for seed extraction.     

Enzymatic Hydrolysis of Shrimp Head Waste: Functional and Biochemical Properties

Shrimp head of Penaeus kerathurus obtained from industrial processing, were hydrolyzed by commercial trypsin (0.1%). Hydrolysis reaction was terminated by heat inactivation of the enzyme (95°C) followed by centrifugation. The produced protein hydrolysates were characterized by biochemical analysis for protein content, total free amino acids (FAA), total volatile basic nitrogen (TVB-N) and electrophoresis SDS-PAGE profile. Functional properties such as emulsifying capacity, fat adsorption and foaming property were assessed. Compared to the raw shrimp head protein, results from enzymatic hydrolysis showed a significant increase (p?<?0.05) in protein content and FAA (17.22%). The low level of trypsin used in this study was sufficient to solubilize the substrate, resulting in substantial protein contents and TVB-N levels (< 6mg/100g), which was significantly lower than the acceptable limits established for marine products.     

Ultimate strength of pin-loaded composite laminates: A limit analysis approach

A simplified approach to determining the ultimate strength of a pin-loaded composite laminate (PLCL), based on limit analysis theory, is presented. The composite laminate is treated as a multilayered deformable three-dimensional solid. The upper bound theorem of limit analysis and kinematic fields that include discontinuities in plies and interfaces are used to predict the bearing strength of pin-loaded composite laminate. An analytical estimation of the ultimate failure load is obtained. The theoretical predictions are compared to available experimental results. The effects of the geometry and the number of interfaces on PLCL strength are also examined.     

Effects of high temperatures on mortar specimens containing Portland cement and GGBFS

During a fire, concrete is submitted to very high temperatures which can lead to structural collapse. The aim of this research is to study the behaviour of mortar specimens made of Portland cement and ground granulated blast furnace slag (GGBFS) which are heated to 900?°C. The samples are submitted to compressive and flexural strength tests and the microstructure is analysed by thermogravimetric analysis (TG and DTA), analysis and mercury intrusion porosimetry. The results indicate that a substitution rate of Portland cement by GGBFS of over 50?% gives residual compressive strengths that, after heating to 600?°C, are close to initial strengths before heating. The greater quantities of bound water, an acceleration of the hydration process due to heating and a lower porosity for specimens with GGBFS explain this increase. At 900?°C, the strong degradation of the microstructure results in strengths of less than 20?% of the initial strengths for specimens with or without GGBFS. Also, after cooling, the GGBFS reduces lime rehydration because of the decomposition of the portlandite between 450 and 550?°C, thus avoiding the risk of concrete cracking.     

Service management in secure and QoS-aware wireless enterprise networks

Wireless local-area networks (WLANs) based on the IEEE 802.11 technology have been widely adopted for private use over the past few years. However, several issues remain concerns for large-scale deployment in corporate environments. Enforcing security and quality-of-service (QoS) has become a fundamental challenge to managing IEEE 802.11-based enterprise networks. In order to provide corporate networks with a global management solution, we have designed a service-oriented management system that enables user-centric service provisioning, while enforcing security and QoS requirements. As enterprises may be comprised of a number of distinct networks, we have extended our system to support the roaming of users between different enterprise sites. In this paper, we describe the design, implementation, and performance evaluation of our solution.     

Development of a decision-making strategy to improve the efficiency of BPR

To support the efficient appraisal of and selection from a list of generic business process improvement principles, this paper proposes a strategy for the implementation of business process redesign (BPR). Its backbone is formed by the analytic hierarchy process (AHP) multicriteria method and our earlier research into the popularity and impact of a set of redesign “best practices”. Using AHP, we derive a classification of most suitable directions for a particular process to be redesigned. Criteria such as the popularity, the impact, the goals and the risks of BPR implementation are taken into account. A case study is included to demonstrate the method’s feasibility and effectiveness.     

Variable window adaptive Kernel Principal Component Analysis for nonlinear nonstationary process monitoring

On-line control of nonlinear nonstationary processes using multivariate statistical methods has recently prompt a lot of interest due to its industrial practical importance. Indeed basic process control methods do not allow monitoring of such processes. For this purpose this study proposes a variable window real-time monitoring system based on a fast block adaptive Kernel Principal Component Analysis scheme. While previous adaptive KPCA models allow only handling of one observation at a time, in this study we propose a way to fast update or downdate the KPCA model when a block of data is provided and not only one observation. Using a variable window size procedure to determine the model size and adaptive chart parameters, this model is applied to monitor two simulated benchmark processes. A comparison of performances of the adopted control strategy with various Principal Component Analysis (PCA) control models shows that the derived strategy is robust and yields better detection abilities of disturbances.     

An assessment of the kernel‐distance‐based multivariate control chart through an industrial application

Traditional multivariate quality control charts assume that quality characteristics follow a multivariate normal distribution. However, in many industrial applications the process distribution is not known, implying the need to construct a flexible control chart appropriate for real applications. A promising approach is to use support vector machines in statistical process control. This paper focuses on the application of the ‘kernel‐distance‐based multivariate control chart’, also known as the ‘k‐chart’, to a real industrial process, and its assessment by comparing it to Hotelling's T² control chart, based on the number of out‐of‐control observations and on the Average Run Length. The industrial application showed that the k‐chart is sensitive to small shifts in mean vector and outperforms the T² control chart in terms of Average Run Length. Copyright © 2010 John Wiley & Sons, Ltd.     

Hygrothermal behavior modeling of the hygroscopic envelopes of buildings: A dynamic co-simulation approach

High levels of humidity in buildings lead to building pathologies. Moisture also has an impact on the indoor air quality and the hygrothermal comfort of the building’s occupants. To better assess these pathologies, it is necessary to take into account the heat and moisture transfer between the building envelope and its indoor ambience. In this work, a new methodology was developed to predict the overall behavior of buildings, which combines two simulation tools: COMSOL Multiphysics© and TRNSYS. The first software is used for the modeling of heat, air and moisture transfer in multilayer porous walls (HAM model: Heat, Air and Moisture transfer), and the second is used to simulate the hygrothermal behavior of the building (BES model: Building Energy Simulation). The combined software applications dynamically solve the mass and energy conservation equations of the two physical models. The HAM-BES coupling efficiency was verified. In this paper, the use of a coupled (HAM-BES) co-simulation for the prediction of the hygrothermal behavior of building envelopes is discussed. Furthermore, the effect of the 2D HAM modeling on relative humidity variations within the building ambience is shown. The results confirm the importance of the HAM modeling in the envelope on the hygrothermal behavior and energy demand of buildings.     

Numerical evaluation of the particle pollutant homogeneity and mixing time in a ventilated room

With the increase of the computational capability, three-dimensional Lagrangian simulation can now be applied to evaluate the particle pollution evolution in ventilated rooms. The present study deals with the evaluation of 5.0 μm particle dispersion in a prototypical-ventilated room of 10 m³. Two ventilation slots and three different airflow rates have been simulated. Particle trajectories have been calculated using a Lagrangian model. Dispersion of particles has been analyzed for the case of an external pollutant source, a homogeneous particle injection within the room and some puff releases in different locations. Discussion about the best procedure to get useful information about the particle cloud is then presented and illustrated from the simulation results. The definition of two indices based on geometrical and statistical parameters are proposed in order to correctly evaluate the particle cloud homogeneity and mixing time.