The effect of the N-linked glycans on structural features and physicochemical functions of soybean β-conglycinin homotrimers

β-Conglycinin is a trimeric protein consisting of three subunits, α,α′,and β, which are N-glycosylated. The α and α′ subunits contain extension regions in addition to core regions common to all subunits. We purified homogeneous trimers consisting of only α, α′, or β from mutant soybean cultivars containing β-conglycinin lacking one or two subunits: α homotrimers from an α′-lacking mutant, α′ homotrimers from an α-lacking mutant, and β homotrimers from an α-and α′-lacking mutant. Structural features and physicochemical functions of the three homotrimers were examined and compared with those of recombinant homotrimers having no N-linked glycans. The native homotrimers have secondary structures very similar to those of the recombinant ones. In analogy with the recombinant homotrimers, the native ones exhibit different thermal stabilities from one another (β>α′>α), and the native α and α′ homotrimers exhibit better solubility, emulsifying ability, and heat-induced association than the native β homotrimer. Further, the N-linked glycans contribute to solubilities of the three subunits at low ionic strength (μ=0.08) and to the emulsifying ability of the native β homotrimer. N-Linked glycans also prevent heat-induced associations of the native α and α′ homotrimers but do not contribute to the secondary structure and the thermal stability of β-conglycinin.     

Improving Methodologies for Transboundary Impact Assessment in Transboundary Watercourses: Navigation Channel Improvement Project of the Lancang-Mekong River from China-Myanmar Boundary Marker 243 to Ban Houei Sai of Laos

This paper analyzes the factors underpinning transboundary Environmental Impact Assessment (EIA) methodologies through an examination of the Navigation Channel Improvement Project of the Lancang-Mekong River from China-Myanmar Boundary Marker 243 to Ban Houei Sai of Laos. A comparison of the project's expected and reported transboundary impacts shows that the EIA failed to predict a number of adverse impacts, including social and economic impacts. The restricted scale and scope of the transboundary impact assessment (TIA) is probably due to certain fundamental restrictions on how the EIA was conducted. The case study highlights the importance of public involvement (including advance notification) and adequate regulatory frameworks or guidelines in the EIA and TIA processes.     

High quality epitaxial ZnO films grown on solid-phase crystallized buffer layers

High quality epitaxial ZnO films on sapphire (110) plane have been fabricated on ZnO homo-buffer layers crystallized via solid-phase epitaxially (SPE). The SPE-ZnO films are fabricated by annealing of amorphous ZnON (a-ZnON) films deposited by RF magnetron sputtering. During annealing, the a-ZnON films are oxidized and converted to ZnO crystal. X-ray diffraction (XRD) analysis shows that the resultant films are epitaxially grown on the sapphire substrates. By using the SPE-ZnO films as homo-buffer layers, the ZnO films with high crystallinity, which are deposited by RF magnetron sputtering, are fabricated. The full width at half-maximum of XRD patterns for 2θ-ω and ω scan of (002) plane are 0.094° and 0.12°, respectively, being significantly small compared with 0.24° and 0.55° for the films without buffer layers. Thus utilizing SPE buffer layers is very promising to obtain epitaxial ZnO films with high crystallinity.     

Structure and photoactivity of titania derived from nanotubes and nanofibers

In the present study, accumulation and distribution of toxic metals (Cu, Cd, Cr, Zn, Fe, Ni, Mn, and Pb) and their biochemical effect on wheat and mustard plants irrigated with mixed distillery and tannery effluents are reported. Analyses of effluents and soil samples have shown high metal content than the permissible limit except Pb. Further, analyses of plant samples have indicated the maximum accumulation of Fe (340 mg kg(-1) in wheat root and 560 mg kg(-1) in mustard leaves) followed by Mn and Zn in root>shoot>leaves>seeds. Maximum increase in photosynthetic pigment was observed between 30 and 60 days while protein content was found maximum between 60 and 90 days of growth period in both plants. An increase in malondialdehyde, cysteine and ascorbic acid antioxidants content was also observed in root and leaves of treated plants upto 60 and 90 days of growth. Hence, wheat and mustard plants irrigated with effluents without adequate treatment are health hazards for environment, humans and animals.     

A Genome-Wide Screen Reveals That Endocytic Genes Are Important for Pma1p Asymmetry during Cell Division in Saccharomyces cerevisiae

An asymmetry in cytosolic pH between mother and daughter cells was reported to underlie cellular aging in the budding yeast Saccharomyces cerevisiae; however, the underlying mechanism remains unknown. Preferential accumulation of Pma1p, which pumps cytoplasmic protons out of cells, at the plasma membrane of mother cells, but not of their newly-formed daughter cells, is believed to be responsible for the pH increase in mother cells by reducing the level of cytoplasmic protons. This, in turn, decreases the acidity of vacuoles, which is well correlated with aging of yeast cells. In this study, to identify genes that regulate the preferential accumulation of Pma1p in mother cells, we performed a genome-wide screen using a collection of single gene deletion yeast strains. A subset of genes involved in the endocytic pathway, such as VPS8, VPS9, and VPS21, was important for Pma1p accumulation. Unexpectedly, however, there was little correlation between deletion of each of these genes and the replicative lifespan of yeast, suggesting that Pma1p accumulation in mother cells is not the key determinant that underlies aging of mother cells.     

Production of low electron temperature ECR plasma for plasma processing

Low-electron-temperature ECR plasma with high electron density was realized under the mirror magnetic field configuration in the H₂ and the Ar/N₂ plasma. Especially, the electron temperature was observed to be less than 2 eV in the Ar/N₂ plasma. It was found from the calculation of particle and power balance in steady state that the decrease in the electron temperature observed in the Ar/N₂ plasma was due to the effect of the magnetic-mirror confinement of the N₂ plasma. Furthermore, our calculated results suggest that the effect of magnetic-mirror on the decrease in the electron temperature depends on the collisional cross section between electrons and neutral particles.     

Effects of Diffuser Vane Geometry on Interaction Noise Generated from a Centrifugal Compressor

The characteristics of interaction tone noise radiated from a centrifugal compressor with a vaned diffuser are discussed by experiments, including visualization techniques using the oil-film method. Research attention is paid to the leading edge geometries of the diffuser vanes that are deeply related to the generation mechanism of the interaction tone noise. The compressor-radiated noise can be reduced by several decibels by setting some clearances in both the hub and shroud surfaces of the diffuser wall along with some decline in the pressure-rise coefficient. Since the decline turned out to be caused by the flow impingement and also by the secondary flow within the diffuser passages, several new types of diffuser vane geometries which do not detract from both the performance and noise level are developed and utilized for the experiments. The presented diffuser vane geometries will offer a few basic guidelines for the diffuser vane design.     

The politics of water transfer between South Africa and Lesotho: Bilateral cooperation in the Lesotho Highlands water project

Abstract

This paper demonstrates that cooperation over international rivers can be achieved through situations where benefits of river development create bilateral dependence between basin states. The case study of the Lesotho Highlands Water Project, a bilateral water transfer in the Orange River basin between South Africa and Lesotho, is examined. Historical analysis of the negotiations leading to the project treaty agreement show that issues of apartheid and the Cold War heavily influenced the riparian relations between the two states. At times, the project faced the threat of abandonment due to deteriorating diplomatic conditions. However, the project was realized because South Africa and Lesotho not only shared the material benefits of the project, but also gained politically from committing to it. These political benefits are influential in creating interdependence between the basin states in order to ensure the reliability of bilateral cooperation.     

Effects of frozen storage temperature on the quality and oxidative stability of bigeye tuna flesh after light salting

Effects of frozen storage temperature on the quality and oxidative stability of lightly salted tuna were investigated. The bright and vivid colour became totally brown after 4 weeks at −20 °C and 8 weeks at −30 °C, where the a^*/b^* value decreased from 1.35 to 0.38 and 0.58, respectively. Discoloration and lipid oxidation occurred concurrently in lightly salted tuna flesh, and it was speculated that the oxidation of oxymyoglobin to metmyoglobin exacerbated lipid oxidation and vice versa. Storage at −40 °C or lower temperatures effectively suppressed the discoloration and maintained the high water-holding capacity and unique textural properties of lightly salted flesh. It was attributed to the reduction in the conformational changes and particularly hydrophobic interactions among proteins, protecting the myoglobin from oxidative damages during frozen storage. Considering the quality maintenance and energy savings, storage at −40 °C was appropriate for lightly salted tuna flesh.