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Abstract: Homogalacturonic and homoglucuronic acid sequences, with various molecular weights and corresponding monomer, were mixed with cholesterol or linolenic acid in controlled conditions (pH, temperature, concentration), then studied by 1H and 13C NMR. The variation of 13C NMR chemical shifts showed the formation of interactions between cholesterol or linolenic acid and carbohydrate sequences depending the molecular weight. Galacturonic acid sequences revealed to be more suitable than glucuronic acid sequences to entrap cholesterol or linolenic acid molecules probably due to the difference of conformation of the two molecules. [Copyright &y& Elsevier]

Abstract: Nitrogen-fixing bacteria isolated from root nodules of Medicago plants growing in the 10 km zone around the Chernobyl nuclear power plant were screened for the production of new water-soluble acidic exopolysaccharides (EPSs). The different strains belonged to the Enteriobacteriaceae family (Enterobacter ludwigii, Raoultella terrigena, Klebsiella oxytoca), except for one which belonged to the Rhizobiaceae family (Sinorhizobium meliloti). All of the bacteria produced highly viscous EPS with an average molecular weight comprised between 1 × 106 and 3 × 106 Da. Five different compositions of EPS were characterized by physico-chemical analyses and 1H NMR spectroscopy: galactose/mannose (2/1), galactose/glucose (1/1), galactose/glucose/mannose (1/2/1), fucose/galactose/glucose (2/1/1) and fucose/galactose/glucose/mannose (2/2/1/1 or 1/1/2/4). Glucuronic acid, a charged monosaccharide, was also recovered in most of the different EPSs. [Copyright &y& Elsevier]

A rapid method for the determination of the degrees of methylation (DM) and acetylation (DA) of pectins was developed. The polymer substitution degree as determined after saponification at 80 °C with NaOD during 1H NMR analysis. Under alkaline conditions, the cleavage of O-acetyl and O-methyl linkages allows the detection and the integration of the H-4 signal from galacturonic acid residues in the newly unesterified pectins. So, after a 10-min NMR recording, sodium acetate and sodium methanolate can be easily quantified relative to the clearly identified H-4 signal in galacturonic acid residues. Protons signals from pectin neutral sugars do not interfere with H-4. During the analysis, a limited (<3%) methanol evaporation leading to a weak reduced signal from the methanolate protons was observed. The proposed method allows in few minutes an accurate simultaneous quantification of DM and DA from few mg of pectin extracts, without the need of external standards. [Copyright &y& Elsevier]

Describes a fault-tolerant system that is based on two replicas of a self-checking module, as it pertains to computer science. Analysis of the competitiveness of the fault-tolerant scheme; Background on self-checking and fail-safe systems; Information on self-checking-based fault tolerant systems.

Introduces a series of articles on microelectromechanical systems and the thermal investigations of integrated circuits and systems.

Introduces a series of articles on the effects of temperature on integrated circuits and systems.

An introduction to the journal is presented in which the editor discusses various articles within the issue on topics including sensors, Micro-Electro Mechanical System (MEMS) accelerometers, and in-vitro diagnostic device.

Introduces series of articles regarding integrated circuits, packages and microelectromechanical systems and application of thermal and electro-thermal effect.

The article discusses various reports published within the issue and were presented at the symposium of Micro-Electro-Mechanical Systems (MEMS)/Micro-optoelectromechanical systems (MOEMS) in 2010 including a collection of papers on design, modeling and simulation of devices.

The article introduces a series of reports on topics related to microsystem technologies published within the issue, including three-dimensional (3D) integration, bio-microelectromechanical systems (MEMS) and manufacturing.

Abstract: From green tea leaves, two distinct pectin fractions were obtained based on their solubility in water. Polyphenols were detected only in the easily water soluble fraction (P1). The estimated uronic acids/neutral sugars ratio was 1.7 in the easily water soluble pectin fraction (P1), and 1.0 in the less water soluble fraction (P2). Homogalacturonan sequences (HGAs) corresponded to about 62% of the P1 pectin fraction but only 47% of the P2 fraction. After degradation of the two pectin fractions by pectin lyase, chemical studies revealed rhamnogalacturonan RG I and RG II regions present in the P1 pectin fraction, whereas only RG I sequences were detected in the P2 pectin fraction. The degree of substitution was lower for HGAs of the P1 pectin fraction than P2. Different acetylation patterns for the two fractions were observed. Polyphenols extracted simultaneously with pectins were present only in HGA fractions from P1. [Copyright &y& Elsevier]

The efficacy of two algal saccharides, glucuronan and oligoglucuronans (average degree of polymerization = 3), against postharvest blue mold ( Penicillium expansum) and gray mold ( Botrytis cinerea) on apple fruit ( Malus domestica Borkh. cv Golden Delicious) and the related-defense responses involved were evaluated. The severity of both blue and gray mold in apple fruits was reduced with the greatest efficacy being achieved using oligoglucuronans. Moreover, glucuronan and its oligomers trigger a rapid and transient accumulation of hydrogen peroxide (HO) as well as the activation of antioxidant-related enzymes, namely catalase (CAT) and superoxide dismutase (SOD). These algal saccharides increased also the activities of phenylalanine ammonialyase (PAL), peroxydase (POD), and polyphenoloxydase (PPO) as well as the levels of lignin and phenolic compounds. These results suggest that the protective effects of glucuronan and oligoglucuronans on apple might be due to its ability on activating an onset-related defensive enzymes and metabolites instead of its direct antifungal activity on the pathogens. These findings showed that glucuronan and even more oligoglucuronans treatments could be a promising method to reduce dependency on synthetic fungicides. [ABSTRACT FROM AUTHOR]

Plant metabolite profiling is commonly carried out by GC–MS of methoximated trimethylsilyl (TMS) derivatives. This technique is robust and enables a library search for spectra produced by electron ionization. However, recent articles have described problems associated with the low stability of some TMS derivatives. This limits the use of GC–MS for metabolomic studies that need large sets of qualitative and quantitative analyses. The aim of this work is to determine the experimental conditions in which the stability of TMS derivatives could be improved. This would facilitate the analysis of the large-scale experimental designs needed in the metabolomics approach. For good repeatability, the sampling conditions and the storage temperature of samples during analysis were investigated. Multiple injections of one sample from one vial led to high variations while injection of one sample from different vials improved the analysis. However, before injection, some amino acid TMS derivatives were degraded during the storage of vials in the autosampler. Only 10% of the initial quantity of glutamine 3 TMS and glutamate 3 TMS and 66% of α-alanine 2 TMS was detected 48 h after derivatization. When stored at 4 °C until injection, all TMS derivatives remained stable for 12 h; at −20 °C, they remained stable for 72 h. From the integration of all these results, a detailed analytical procedure is thus proposed. It enables a robust quantification of polar metabolites, useful for further plant metabolomics studies using GC–MS. [ABSTRACT FROM AUTHOR]

Abstract: Poly- and oligosaccharides isolated from the green algae Ulva lactuca were tested for their capacity elicitor of natural defences in tomato seedlings. After internodal infiltration of the bioelicitor solution in the midstem of tomato seedlings, the elicitor capacities were evaluated by determining the activity of phenylalanine ammonia-lyase (PAL) in the leaves located above and below the elicitation site. The results obtained showed that the crude extract of U. lactuca polysaccharides expressed an elicitor capacity of PAL activity in leaves. This expression level was similar and even higher than the ones due to other algae polysaccharides (carrageenan, laminarin and alginate). The crude extract of polysaccharides contained two polysaccharides, the glucuronan (unsulfated homopolymer) and the ulvan (sulfated heteropolymer). The glucuronan had no significant elicitor effect whereas the ulvan induced an elicitor capacity higher than that of the crude polysaccharidic extract. The desulfation of the ulvan caused a suppression of its elicitor capacity of PAL activity. The oligoulvans (sulfated β-Δ-(4,5)-oligorhamnoglucuronans, degree of polymerization average=2) and the oligoglucuronans (β-Δ-(4,5)-oligoglucuronans, degree of polymerization average=3) were prepared from the ulvan and the glucuronan using two specific enzymes a ulvan lyase and a glucuronan lyase, purified from the bacterial strain Ochrobactrum sp. PEC2. The treatment of tomato seedlings with the oligoulvans was accompanied by a strong stimulation of PAL activity, reaching a maximum activity of 2–2.5 times higher than that of the ulvan polymer. Although the oligoglucuronans expressed an elicitor capacity in PAL activity twice higher than that of the glucuronan polymer, its induction was less important than the oligoulvans. The high elicitor capacity of these saccharides seemed to be related to sulfate substituents and the rhamnose residues. The stimulation of PAL activity was accompanied by an increase of phenolic compounds content and an induction of salicylic acid in the leaves located above and below the elicitation site. The treatments of tomato seedlings with U. lactuca elicitors significantly reduced wilt development caused by Fusarium oxysporum f. sp. lycopersici. The percent of wilting and mortality after 45 days was markedly reduced when plants were treated with oligoulvans, respectively 44% and 54% compared to the control plants. The whole of these results showed clearly those U. lactuca elicitors, particularly the ulvan and the oligoulvans, induced in tomato seedlings the stimulation of natural systemic defences accompanied by a systemic acquired resistance that seems to be salicylic acid-dependent. [Copyright &y& Elsevier]

Abstract: In this study, we showed that oligogalacturonic acid (OGA) purified from flax pectin inhibit in vitro osteoclastic bone resorption in a dose-dependent manner. The OGA inhibitory effect was neither linked to an effect on osteoclast apoptosis, nor to an inhibition of cathepsin K activity. By means of an in vitro collagen degradation assay we demonstrated that OGA prevented triple-helical type I collagen cleavage by cathepsin K in a dose and chain length dependent manner. This inhibition was not restricted to cathepsin K, since collagenolytic activity of other lysosomal cysteine proteases, such as cathepsin B and cathepsin L, as well as matrixmetalloproteinases such as MMP-9 were also inhibited. Interestingly, using non-collagen substrates we demonstrated that OGA does not inhibit the proteolytic activity of cathepsin B and L, suggesting that OGA inhibits collagen degradation without affecting the lysosomal cysteine enzyme proteolytic activity. Finally, preliminary study using surface plasmon resonance (SPR) showed that OGA binds to type I collagen but not to albumin, consistent with a specific effect on collagen. These results suggest that the observed inhibition of collagen degradation by OGA may be due to its ability to bind to the collagen molecule. By masking the collagen surface, OGA may render the collagen cleavage site less accessible to enzymes and thus prevent its enzymatic degradation. [Copyright &y& Elsevier]

Abstract: Ion-exchange chromatography has been applied to purification of unsaturated oligoglucuronans. After an isocratic elution on a strong anion-exchange column, the collected fractions were desalted by low pressure size exclusion chromatography. However, this efficient separation was limited by the time required to desalt. So, we developed a reversed-phase chromatography method using back ionization of oligomers. Two C18 columns were tested with trifluoroacetic acid (TFA 0.7%) as eluent. Different selectivities and column stabilities were observed in this acidic condition. The scale up for semi-preparative applications enabled us to recover pure unsaturated oligoglucuronans without desalting step. [Copyright &y& Elsevier]

This paper reports recent advances in the development of a tactile fingerprint sensor made by a CMOS compatible front side bulk micromachining technology. This device enables the measurement of a fingerprint by the way of a mechanical scanning principle of the finger roughness. While this sensing principle has shown good results on a first prototype of reduced width, we present here the design, fabrication and test of a new sensor. This sensor contains 256 pressure sensitive microbeams for a total length of 1.28 cm and is fully integrated with analog and mixed signal electronics. In this paper we will detail the general working principle of the tactile fingerprint sensor and the two prototypes that have been manufactured and tested with a special focus on the electronic architecture and the test results of the second prototype. [ABSTRACT FROM AUTHOR]

Examines the purification and properties of a glucuronan lyase from Sinorhizobium meliloti M5N1CS. Purification of M5N1CS by anion-exchange chromatography; Production of 4,5-unsaturated oligoglucuronates; Components of the lyase cleaving mechanism; Degradation of deacetylated glucuronan.