Effects of environmental factors and agricultural techniques on antioxidantcontent of tomatoes

Antioxidants are believed to be important in the prevention of diseases such as cancer and cardiovascular disease. Lycopene is one of the main antioxidants to be found in fresh tomatoes and processed tomato products. The lycopene content also accounts for the redness of the fruit, which is one of the main qualities for which industry and consumers now look. Other carotenes (such as β‐carotene), vitamin C, vitamin E and various phenolic compounds are also thought to be health‐promoting factors with antioxidant properties. Since the antioxidant content of tomatoes may depend on genetic factors, the choice of variety cultivated may affect the results at harvest. To be able to control the antioxidant content of tomatoes at the field level when growing a given variety, it is necessary to know the effects of both environmental factors and the agricultural techniques used. Temperatures below 12 °C strongly inhibit lycopene biosynthesis and temperatures above 32 °C stop this process altogether. The effects of the temperature on the synthesis of other antioxidants have not yet been properly assessed. The effects of light have been studied more thoroughly, apart from those on vitamin E. The effects of water availability, mineral nutrients (nitrogen, phosphorus, potassium and calcium) and plant growth regulators have been studied, but results are sometimes contradictory and the data often incomplete. During the ripening period, lycopene content of tomatoes increases sharply from the pink stage onwards, but no sufficient attempts have been made so far to assess the changes in the other antioxidants present in the fruit. This paper reviews the present state of the art. Copyright © 2003 Society of Chemical Industry     

Test quality of hierarchical defect-tolerant integrated circuits

This paper presents a theoretical expression to evaluate the test quality of hierarchical defect-tolerant integrated circuits. This expression, which is developed for circuits with two levels of hierarchy, is based on a defect model with which one can take into account the relative importance (probability of occurrence) of each defect and consequently of each fault. Results obtained from this expression show that, for a given test coverage, the addition of defect-tolerance mechanisms decreases the test quality of integrated circuits. These results are important because they indicate that fault coverage can be a misleading measure of the test quality of defect-tolerant integrated circuits.     

Modeling, design and implementation of a low-power FPGA based asynchronous wake-up receiver for wireless applications

Power consumption is a major concern for wireless sensor networks (WSNs) nodes, and it is often dominated by the power consumption of communication means. For such networks, devices are most of the time battery-powered and need to have very low power consumption. Moreover, for WSNs, limited amount of data are periodically sent and then the radio should be in idle or deep sleep mode most of the time. Thus using event-triggered radios is well suited and could lead to significant reduction of the overall power consumption of WSNs. Therefore this paper explores the design of an asynchronous module that can wake up the main receiver when another node is trying to send data. Furthermore, we implement the proposed solution in an FPGA to decrease the fabrication cost for low volume applications and make it easier to design, re-use and enhance. To decrease the static power consumption, we explore the possibility of reducing the supply voltage. The observed overall power consumption is under 5 μW at 250 kbps. Moreover, using a new asynchronous design technique, we observed that power consumption can be further reduced.     

Update of the French R&D strategy on gas-cooled reactors

Gas-cooled reactors take up a strong second role in France's R&D strategy on future nuclear energy systems as priority was given in 2005 to fast neutron reactors with multiple-recycle for their potential to optimally use uranium resource and minimize the long term burden of radioactive waste. Owing to the European past experience on sodium-cooled fast reactors (SFRs), this reactor type was logically selected as reference for a new generation fast neutron reactor intended to be tested as a prototype in the 2020s and be ready for industrial deployment around 2040. At the same time, the potential merits of a gas fast reactor (GFR) with ceramic clad fuel for a safe management of cooling accident are acknowledged for the potential of this reactor type to resolve critical issues of liquid fast reactors (safety, operability and reparability). A pre-feasibility report on a first concept of GFR was issued in 2007 that summed-up results of a 5-year international R&D effort on GFR fuel technology, reactor design and operating transient analyses. This report established a global confidence in the feasibility of this concept and its potential for attractive performances. Furthermore, it suggested directions of R&D to generate by 2012 an updated concept with improved performances and taking better benefit from GFR specific technologies.A second activity on gas-cooled reactors originates from the current interest of CEA's industrial partner AREVA in high or very high temperature reactors (V/HTR) for supplying hydrogen, synthetic hydrocarbon fuels and process heat for the industry. This activity currently encompasses R&D on V/HTR key technologies such as particle fuel fabrication, high temperature compact heat exchangers and coupling technologies to various power conversion systems. R&D on V/HTR and GFR are synergistic in various respects. The GFR can be viewed as a more sustainable version of the VHTR and synergies exist in research on heat resisting materials, helium system technology and power conversion systems. Both reactors require active research in materials and spur developments of new metallic alloys and ceramics applicable to other advanced nuclear systems.     

Differential responses to serotonin receptor ligands in an impulsive-aggressive phenotype.

Offensive aggression in golden hamsters is inhibited by 5-hydroxytryptamine (5-HT)1A receptors and facilitated by 5-HT3 receptor activation. As such, we sought to determine whether these receptors function similarly between animals expressing an impulsive-aggressive phenotype, as compared to normal animals. Animals were screened for aggressive and impulsive choice behaviors and categorized into Low-Aggression (L-Agg) and High-Aggression (H-Agg) groups, and then tested for behavior under effective doses of 5-HT1A receptor agonist 8-hydroxy-N, N-dipropyl-2-aminotetralin (DPAT; 0.1 mg/kg and 0.3 mg/kg) or 5-HT3 receptor antagonist tropisetron (0.3 mg/kg) treatment. Low-dose DPAT treatment inhibited both behaviors in H-Agg animals, however yielding more modest effects in L-Agg animals; while high-dose DPAT effects were confounded by side effects on locomotion. Tropisetron, on the other hand, had differential effects between groups, as aggression and impulsive choice were both inhibited in H-Agg animals, while enhanced in L-Agg individuals. In addition, while the effects of the 5-HT1A receptor were limited, the broad effects of 5-HT3 receptor included repetitive and impulsive elements of behavior, pointing to the importance of the receptor's role in the modulation of these particular aspects within the phenotype. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An advanced computer algorithm for determining morphology development in latex particles

A new algorithm is presented for the prediction of equilibrium morphology in latex particles. Thermodynamic equilibrium calculations of the interfacial free energies associated with a large array of possible morphologies serve to create a continuous free-energy surface upon which the preferred morphology is located. When the computations are performed on a 486DX33 PC, the calculations are essentially instantaneous. The graphical output can be refreshed on the monitor screen in less than 2 s. The algorithm is applied to simulate the conversion-dependent morphology for several latex systems composed of polystyrene and poly(methyl methacrylate) and two very different surfactants. © 1995 John Wiley & Sons, Inc.     

Crystal growth of Ti n O2n-1 oxides(n=2 to 9)

Crystals of titanium oxides, Ti _n O_2n-1 with n=2 to 9, were grown by chemical vapour transport. Chlorine was found to be the best transporting agent. Apart from Ti₂O₃, for which crystals up to 7 mm long were obtained in 6 days, all phases were obtained in conditions leading to very low growth rates and a shift in composition between the charge and growth zones. It is shown that this shift is governed by the equilibrium oxygen pressure in the transport tubes and can be accurately predicted. Most of the millimetresize samples obtained were twinned.     

Characterization of dupont photopolymer: determination of kinetic parameters in a diffusion model

We investigate the recording dynamics of Omnidex photopolymer film from DuPont. We use a reviewed version of the diffusion model proposed by Zhao and Mouroulis [J. Mod. Opt. 41, 1929 (1994)] in order to describe the recording response that combined photopolymerization and free-monomer diffusion process. Two different experiments are detailed that lead to the determination of material kinetic parameters. These values are introduced in the numerical model to provide quantitative simulations of a grating formation under various holographic exposures. Theoretical results are experimentally checked as a validation of the model. We extend its applications to several secondary investigations, such as volume-shrinkage influence on refractive-index distribution and spectral selectivity of reflection gratings. This study improves the understanding of the recording process and consequently allows to build more accurate holographic components in this material to be built.     

A framework for a distributed CAD system

The DIJA project is a web-based CAD system accessible to any user (from neophyte to expert) and from a simple desktop computer. Its modeling approach is based on a top-down methodology and takes into account trade information. In this paper, we propose a network architecture based on a replication process and a multi-level language to manage the consistency between the client model and the server model. The whole CAD system is based on a modular architecture communicating with messages exchanges and provides a general architecture for all trade CAD applications.     

Physicochemical properties of talc ore from three deposits of Lamal Pougue area (Yaounde Pan-African Belt, Cameroon), in relation to industrial uses

Three talc deposits were discovered at Ngoung, Lamal Pougue and Bibodi Lamal (Cameroon). They derived from ultramafic rocks and are enclosed in a Pan-African garnet and muscovite-bearing mica schist of the Yaoundé series. The physico-chemical properties of these talc deposits have been investigated by different techniques including Scanning Electron and Transmission Microscopy (SEM and TEM), chemical analyses, X-ray diffraction (XRD), infrared spectroscopy, particle size analysis by laser diffraction and low temperature gas absorption–desorption. The mineralogical composition deduced from XRD is wide (talc + chlorite + tremolite ± anthophyllite ± chromite ±serpentine ± brucite ± magnesite ± dolomite), but due to the high talc contents (≈ 90%) the samples are close to monomineralic. SEM studies reveal that all talc deposits comprise bundles of platy talc and a few prismatic crystals of amphiboles and other contaminating minerals. Laser diffraction confirms the coarse particle size of the talc crystals. Mode values are as high as 105–170 μm (except two samples displaying 76 and 42 μm) and d50 ranges from 107 to 25 μm. The values of specific surface area measured by BET and t-plot methods range from 1 to 6 m²/g and are correlated with external specific surface area measured by laser diffraction. Discrepancies from the trend are due to the semi-crystalline texture of the samples and mostly to intra-crystalline structural defects revealed by TEM observations. In infrared spectra, specific absorption bands are distinguished for talc, chlorite, tremolite, carbonates, serpentine, brucite and water. Occasional substitutions in minerals led to a shift in some absorption bands. The chemical composition criteria important for most of the industrial applications such as ceramics and pharmaceutics are closely complied with in untreated samples from these deposits. In summary, high talc proportions, chemical compositions, platy morphology and coarse grain size of its crystals lead to the conclusion that the studied deposits are economically attractive. The data set of the present work is an important tool for choosing the beneficiation methods for specific applications.