Functional and bioinformatic characterisation of sequence variants of Fad3 gene from flax

BACKGROUND: Desaturases are enzymes that drive the multi‐step fatty acid biosynthetic pathway. As evident from directed mutagenesis, single base changes in their polypeptide can potentially alter their structure and may result in altered substrate specificity, regioselectivity and even loss of function. The authors have previously isolated several sequence variants of Δ15 desaturase from flax while attempting to clone that gene. The aim of the present study was to analyse these gene variants for their functionality and to predict the tertiary structure of the protein in order to correlate the functional differences with the protein structure. RESULTS: The variants differed in the rate at which they could convert linoleic acid to α‐linolenic acid. The highest conversion rate was 7.03%, while the lowest was 2.39%. The overall shape of the predicted 3D model of the protein is a compact cylinder containing α‐helices and β‐sheets. The Ramchandran plot of this model revealed that 98.5% of the residues are located in allowed region, which denotes a stable structure. CONCLUSION: Although the structures of the variants are apparently similar, subtle changes account for variation in their activity. Besides, these substitutions may alter their cross‐talk with other proteins and thus differentially influence their specificity, localisation and stability, which in turn may explain the diversity in their function. Copyright © 2011 Society of Chemical Industry     

Characterisation and comparison of khoa prepared from camel milk with that from cow and buffalo milk

Khoa, a heat‐concentrated milk product, is used as a base material for the manufacture of many popular sweets. The comparison was made between various chemical compositions and characteristics of the khoa prepared from the camel milk with that prepared from the cow and the buffalo milk samples. The khoa prepared from the camel milk had the higher moisture, ash, acidity, soluble nitrogen, free fatty acids and peroxide value, but lower in fat, protein and lactose contents than that prepared from the cow and buffalo milk samples. There was no significant (P > 0.05) difference in 5‐hydroxymethyl furfural between khoa samples prepared from the three milks.     

Large area tunnel oxide passivated rear contact n‐type Si solar cells with 21.2% efficiency

This paper reports on the implementation of carrier‐selective tunnel oxide passivated rear contact for high‐efficiency screen‐printed large area n‐type front junction crystalline Si solar cells. It is shown that the tunnel oxide grown in nitric acid at room temperature (25°C) and capped with n⁺ polysilicon layer provides excellent rear contact passivation with implied open‐circuit voltage iV_oc of 714 mV and saturation current density J_0b′ of 10.3 fA/cm² for the back surface field region. The durability of this passivation scheme is also investigated for a back‐end high temperature process. In combination with an ion‐implanted Al₂O₃‐passivated boron emitter and screen‐printed front metal grids, this passivated rear contact enabled 21.2% efficient front junction Si solar cells on 239 cm² commercial grade n‐type Czochralski wafers. Copyright © 2016 John Wiley & Sons, Ltd.     

Comparison of different methods of monitoring the secondary stage of oxidation of ghee

Thiobarbituric acid value (TBA), ρ‐anisidine value (ρ‐AnV) and carbonyl value (CV) were compared with sensory scores in monitoring the oxidation of ghee. The latter used a 9‐point hedonic scale for flavour. Six samples of ghee were stored at 80 °C and samples were removed at 48‐h intervals. Correlation coefficients of the chemical values with flavour scores were CV ?0.664, TBA ?0.521 and p‐AnV ?0.356, suggesting that the CV was the most suitable of the methods tested.     

Hardware implementation of tag-reader mutual authentication protocol for RFID systems

Radio-frequency identification (RFID) is a recent technology that utilizes radio frequencies to track the object by transmitting a signal with a unique serial identity. Generally, the drawbacks of RFID technology are high cost and authentication systems between a reader and a tag become weak. In this paper, we proposed a protocol for RFID tag–reader mutual authentication scheme which is hardware efficient and consumes less dynamic power. Truncated multipliers are implemented in RFID tag–reader mutual authentication protocol system due to reduction in hardware cost and dynamic power. Experimental evaluation reveals that the proposed protocol with truncated multipliers provides more security than the earlier schemes. The proposed protocol is described in VHDL and simulated using Altera Quartus II. The functional block is implemented as hardware using an Altera DE2 Cyclone II (EP2C35F672C6) Field-Programmable Gate Array (FPGA).     

Insights and comparisons of the level-2 results of recent probabilistic safety analyses

Observations and insights based on the review of a number of recent level-2 probabilistic safety analyses (PSAs) and individual plant examinations (IPEs) are provided. Observations and comparisons are made regarding plant and containment design characteristics, methods for the analysis of containment response to severe accident loads, modeling of the uncertain phenomenological processes impacting containment response, accident progression and containment analysis, source term calculation, and uncertainty analysis. Insights are obtained which attempt to relate the various plant and containment design characteristics to expected containment performance, though these relationships can often be obscured by the large inherent uncertainties associated with quantification of most level-2 PSA issues.     

Opportunistic Transient-Fault Detection

CMOS scaling continues to enable faster transistors and lower supply voltage, improving microprocessor performance and reducing per-transistor power. The downside of scaling is increased susceptibility to soft errors due to strikes by cosmic particles and radiation from packaging materials. The result is degraded reliability in future commodity microprocessors. The authors target better coverage while incurring minimal performance degradation by opportunistically using redundancy.     

A new generalized switched diode multilevel inverter topology with reduced switch count and voltage on switches

This article presents a new multilevel inverter topology with reduced power switches. The proposed topology composes of several series connection of basic unit for obtaining a required output voltage level. The proposed topology can operate in symmetric condition. The proposed topology is connected in a cascaded structure to produce a higher number of output voltage levels. The proposed cascaded structure is optimized with the minimum number of components for the maximum number of levels. To prove the superiority of the proposed multilevel inverter topology, different technical parameter comparisons are carried out with recently developed multilevel inverter topologies from the literature. The calculation of total standing voltage is examined for the proposed topology. The operation of the proposed topology is tested and verified for nine-level output voltage. The simulated results are carried out, and it is strengthened by the real-time prototype results.     

Bare nanocapillary for DNA separation and genotyping analysis in gel-free solutions without application of external electric field

In this work, we demonstrate DNA separation and genotyping analysis in gel-free solutions using a nanocapillary under pressure-driven conditions without application of an external electric field. The nanocapillary is a approximately 50-cm-long and 500-nm-radius bare fused-silica capillary. After a DNA sample is injected, the analytes are eluted out in a chromatographic separation format. The elution order of DNA molecules follows strictly with their sizes, with the longer DNA being eluted out faster than the shorter ones. High resolutions are obtained for both short (a few bases) and long (tens of thousands of base pairs) DNA fragments. Effects of key experimental parameters, such as eluent composition and elution pressure, on separation efficiency and resolution are investigated. We also apply this technique for DNA separations of real-world genotyping samples to demonstrate its feasibility in biological applications. PCR products (without any purification) amplified from Arabidopsis plant genomic DNA crude preparations are directly injected into the nanocapillary, and PCR-amplified DNA fragments are well resolved, allowing for unambiguous identification of samples from heterozygous and homozygous individuals. Since the capillaries used to conduct the separations are uncoated, column lifetime is virtually unlimited. The only material that is consumed in these assays is the eluent, and hence, the operation cost is low.     

Methyl Yellow: A Potential Drug Scaffold for Parkinson's Disease

Parkinson's disease (PD) is an age‐related neurodegenerative disease affecting movement. To date, there are no currently available therapeutic agents which can prevent or slow disease progression. Here, we evaluated an azobenzene derivative, methyl yellow (MY), as a potential drug scaffold for PD; its inhibitory activity toward monoamine oxidase B (MAO‐B) as well as drug‐like properties were investigated. The inhibitory effect of MY on MAO activity was determined by a MAO enzyme inhibition assay. In addition, the in vitro properties of MY as a drug candidate (e.g., blood–brain barrier (BBB) permeability, serum albumin binding, drug efflux through P‐glycoprotein (P‐gp), drug metabolism by P450, and mitochondrial toxicity) were examined. In vivo effectiveness of MY was also evaluated in the 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) Parkinsonian mouse model. MY selectively inhibited MAO‐B in a dose‐dependent and reversible manner. MY was BBB‐permeable, bound relatively weakly to serum albumin, was an unlikely substrate for both systems of P‐gp and P450, and did not cause mitochondrial toxicity. Results from the MPTP Parkinsonian mouse model indicated that, upon treatment with MY, neurotoxicity induced by MPTP was mitigated. Investigations of MY demonstrate its inhibitory activity toward MAO‐B, compliant properties for drug consideration, and its neuroprotective capability in the MPTP Parkinsonian mouse model. These data provide insights into potential use, optimization, and new design of azobenzene derivatives for PD treatment.