Functional and nutritional value of the Chilean seaweeds Codium fragile,Gracilaria chilensis and Macrocystis pyrifera

The nutritional composition of the edible seaweeds Codium fragile, Gracilaria chilensis and Macrocystis pyrifera was determined, including amino acid and fatty acid contents along with tocol and carotenoid contents. The results indicated that the three algae C. fragile, G. chilensis and M. pyrifera showed a high range of protein contents (13.7–10.8%), amino acid contents (1879.6–1417.7 mg/100 g dry algae) and a low content in lipids (0.7–15.0%). The most abundant fatty acids in C. fragile and G. chilensis were linolenic, oleic, and linoleic acid. δ‐Tocopherol and α‐tocopherol (677.8 and 453.5 µg/g lipid, respectively) were found in C. fragile, while in G. chilensis and M. pyrifera, γ‐tocotrienol and α‐tocopherol (263.5 and 1327.7 µg/g lipid, respectively) were found. In addition, in C. fragile and G. chilensis β‐carotene was the principal carotenoid found (197.9 and 113.7 µg/g dry algae, respectively) compared with M. pyrifera (17.4 µg/g dry algae). The composition of macronutrients (minerals, carbohydrate‐type dietetic fiber, proteins; low in lipids) and micronutrients (essential amino acids, PUFA of balanced n‐6/n‐3 proportion, β‐carotene and α‐tocopherol as source of vitamins A and E), corroborate the nutritional and biological potential of the studied algae, which constitute useful raw materials for the development of diets or ingredients for human and animal nutrition.     

Low-Voltage Super class AB CMOS OTA cells with very high slew rate and power efficiency

A simple technique to achieve low-voltage power-efficient class AB operational transconductance amplifiers (OTAs) is presented. It is based on the combination of class AB differential input stages and local common-mode feedback (LCMFB) which provides additional dynamic current boosting, increased gain-bandwidth product (GBW), and near-optimal current efficiency. LCMFB is applied to various class AB differential input stages, leading to different class AB OTA topologies. Three OTA realizations based on this technique have been fabricated in a 0.5-/spl mu/m CMOS technology. For an 80-pF load they show enhancement factors of slew rate and GBW of up to 280 and 3.6, respectively, compared to a conventional class A OTA with the same 10-/spl mu/A quiescent currents and /spl plusmn/1-V supply voltages. In addition, the overhead in terms of common-mode input range, output swing, silicon area, noise, and static power consumption, is minimal.     

A power efficient and simple scheme for dynamically biasing cascode amplifiers and telescopic op-amps

A simple dynamic biasing scheme to extend the input/output range of cascode amplifiers is introduced. It requires minimum extra hardware and no additional power consumption. A dynamic biased telescopic op-amp is discussed as an application example. Experimental results of a fabricated test chip in 0.5 μm CMOS technology are presented that verify the proposed technique.     

Thermal degradation of high‐temperature fluorinated polyimide and its carbon fiber composite

High‐temperature polymers are being used for a broad range of applications, such as composite matrices for structural applications (e.g., high speed aircraft). Polyimides are a special class of polymers that meet the thermal and oxidative stability requirements for high temperature composite aerospace applications. A weight loss study was performed on a fluorinated polyimide resin and its carbon fiber composite in an effort to determine its thermal stability and degradation mechanisms. Experiments were conducted using a preheated oven and thermogravimetric analysis to obtain the weight loss. Regardless of the method used, the resin and composite exhibited excellent thermal stability (less than 1% weight loss) below 430°C, regardless of 2–20 min of exposure. After 20 min of exposure at 510°C, the composite remained relatively stable with only 5.3% weight loss using the oven technique, whereas the neat polyimide sustained 12.6%. When degradation occurred, it was found to be the result of thermolysis and oxidation (to a lesser extent). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

New quality criteria in wastewater reuse : The case of Gran Canaria

Wastewater reuse plays a key role in this vital cycle of water because it is able to reduce the wastewater spilled. Simultaneously, the supply of water for specific uses is increased. A new regulation (Royal Decree 1620/2007) came into force in Spain in December 2007 and regulates the basic conditions for the wastewater reuse and establishes the required criteria of quality to waters according to use.In the present paper, different kinds of tertiary treatments in reuse of wastewater are described. We focused on the applied tertiary treatments in most wastewater treatment plants of Gran Canaria Island. Particularly, we analysed Hoya del Pozo wastewater treatment plant due to its wide number of technologies and processes.Finally, we reviewed the quality criteria used in the regenerated waters, in agreement with the new regulations.     

A novel pectin material: extraction, characterization and gelling properties

A novel pectin was acid extracted from chickpea husk (CHP). CHP presented a 67% (w/w) of galacturonic acid, an intrinsic viscosity of 374 mL/g and a viscosimetric molecular weight of 110 kDa. Fourier transform infrared spectroscopy spectrum of CHP indicated a degree of esterification of about 10%. The CHP-calcium system formed ionic gels with a storage (G') modulus of 40 Pa and gel set time (G' > G″) of 3 min at 1% (w/v), and a G' of 131 Pa and gel set time of 1 min at 2% (w/v). The G' of CHP gels was not greatly affected by temperature. The results attained suggest that chickpea husk can be a potential source of a gelling pectin material.     

Evaluation of the effect of a maternal rearing system on the odour profile of meat from suckling lamb

The aim was to evaluate the effect of maternal rearing system on the chemical composition and odour profile of meat from suckling lamb. Twenty-four single male suckling lambs raised exclusively on maternal milk came from two rearing systems (extensive and intensive), and from Castellana and Churra breeds. The fatty acid composition of lamb meat from both breeds was affected by the rearing system, and Churra lamb reared under the extensive system had noticeable changes in odour attributes as detected by panellists and an electronic nose. Using partial least squares-discriminant analysis, the electronic nose was able to discriminate accurately between samples of Churra and Castellana meat according to their production system. However, it was not able to correctly classify meat samples from the extensive and intensive systems when both breeds were analysed together. The results suggest a significant effect of the rearing system and breed on suckling lamb meat quality traits.     

Different enrichment procedures for recovery of Listeria monocytogenes from raw chicken samples can affect the results of detection (by chromogenic plating or real-time PCR) and lineage or strain identification

This study aimed to evaluate the effect of different enrichment procedures on the detection of Listeria monocytogenes in food, by a comparison of subculture onto chromogenic agar with real-time PCR. Two different culture media, the primary and secondary enrichment broths of the U.S. Food Safety and Inspection Service (FSIS) method used for PCR detection of L. monocytogenes, were compared for the primary enrichment of retail ground chicken samples. L. monocytogenes was detected after the completion of each enrichment procedure in 63% (complete FSIS procedure) and 60% (plain FSIS secondary enrichment broth incubated for 48 h) of the samples by both culture and PCR, whereas a combination of the results for the two enrichment procedures revealed 86% of the samples to be positive. Most of the samples analyzed contained a mixture of lineage I and II strains, and their ratio varied for each enrichment procedure. This mixture could have a significant effect on the result of detection of L. monocytogenes for each individual sample, explaining the increase in positive samples when the results of the two enrichment procedures were combined. The use of different isolation procedures can affect the specific samples identified as positive and the specific strains isolated.     

Realistic model for the multiple‐input floating‐gate transistor

Multiple‐input floating‐gate transistor (FGMOS) circuit designers face a serious problem along the design process: the lack of a realistic simulation model. For this reason, a solution that properly predicts the initial voltage at the floating gates is presented in this paper. In order to assess the performance of the proposal, a comparison is made against a test circuit fabricated in a 0.5‐µm On‐Semiconductor CMOS process. Based on this comparison, the proposed model is shown to be a fundamental tool in the design of FGMOS circuits. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.