Molecular characterization of the Tim9 homologue from the methylotrophic yeast Pichia methanolica

In this paper we describe molecular characterization of the TIM9 gene encoding the essential mitochondrial inner-membrane protein in the methylotrophic yeast Pichia methanolica. PmTIM9 contains two exons corresponding to a gene product of 89 amino acid residues and a 140 bp intron. The deduced amino acid sequence exhibited high identity to those of other yeast Tim9ps, and possessed two CX(3)C motifs that contained two cysteine residues conserved among small Tim family proteins. Moreover, PmTIM9 had the ability to partially suppress the temperature sensitivity of Saccharomyces cerevisiae strain tim9-3, suggesting that PmTIM9 is a functional homologue of the ScTIM9 gene.     

Purification and properties of glutamine synthetase from Hydrogenobacter thermophilus TK-6

Hydrogenobacter thermophilus TK-6, a thermophilic and obligately chemoautotrophic bacterium, assimilates ammonium using glutamine synthetase (GS). GS was purified using three chromatography steps. The purified GS was found to belong to GS type I on the basis of its subunit composition and molecular weight. The Mg2+ -dependent activity of this GS significantly increased after incubation with phosphodiesterase, indicating that GS is subject to adenylyl/deadenylyl regulation, a posttranslational modification system reported mainly among enterobacteria. The degree of this posttranslational modification changed depending on growth phase, confirming that adenylyl/deadenylyl regulation functions in vivo. Interestingly, the Km for glutamate of H. thermophilus GS was significantly higher than those of other organisms, suggesting that GS activity is affected by intracellular glutamate concentration.     

Liquid-crystal panel with microdots on an electrode used to modulate optical phase profiles

The optical characteristics of a liquid-crystal (LC) panel with microdots on an electrode are investigated. Although 3 mum is larger than 1 molecule of LC material, microdots with a 3 microm diameter are sufficiently small to produce a smooth index profile. We use an electrode patterned in a new way to modulate the index profile of the LC panel, which allows us to modulate the optical phase of the passing light.     

Reduction of Excess Sludge by Magneto-Ferrite Treatment: Observation on Lab Scale WWTPs

We have reported the effect of magneto-ferrite treatment on the growth of excess activated sludge in laboratory scale with extended aeration method. This magneto-ferrite treatment is a new approach for reduction of excess sludge by using ferrite particles and permanent magnets. Two miniature waste water treatment plants were used at the laboratory, one of which was run with magneto-ferrite treatment, whereas other one was run without any treatment. The observations showed good results in the reduction of excess sludge. No evidence of excess sludge was found with magneto-ferrite treatment. The results showed good possibilities of reducing sludge in the arena of biological waste water treatment. © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A 70 nm 16 Gb 16-Level-Cell NAND flash Memory

A 16 Gb 16-level-cell (16LC) NAND flash memory using 70 nm design rule has been developed . This 16LC NAND flash memory can store 4 bits in a cell which enabled double bit density comparing to 4-level-cell (4LC) NAND flash, and quadruple bit density comparing to single-bit (SLC) NAND flash memory with the same design rule. New programming method suppresses the floating gate coupling effect and enabled the narrow distribution for 16LC. The cache-program function can be achievable without any additional latches. Optimization of programming sequence achieves 0.62 MB/s programming throughput. This 16-level NAND flash memory technology reduces the cost per bit and improves the memory density even more.     

A coupled elastoplastic-transient hydrogen diffusion analysis to simulate the onset of necking in tension by using the finite element method

Hydrogen-enhanced localized plasticity (HELP) is an acceptable mechanism for hydrogen embrittlement which is based on the experimental observations and the theoretical computations. The underlying principle in the HELP theory is that the presence of hydrogen causes the localization of the slip bands which results in the decrease of the fracture strength. In a sample under plane-strain tensile stress, plastic instability can lead to either the concentration of plastic flow in a narrow neck or bifurcation from homogeneous deformation into a mode of an exclusively localized narrow band of intense shear. Recently, it has been demonstrated that the presence of hydrogen can indeed induce shear banding bifurcation at macroscopic strains. By using a steady-state equilibrium equation for hydrogen diffusion analysis, the effect of hydrogen on the bifurcation of a homogeneous deformation in a plane-strain tension specimen into a necking or a shear localization mode of deformation has already been studied. In the present research, using a transient hydrogen diffusion analysis and introducing a new constitutive equation accompanied by considering the reduction in the local flow stress upon hydrogen dissolution into the lattice, the effect of hydrogen on shear localization is investigated. In addition, progress has been made in that, the changes in the distribution of the total and trapping hydrogen concentrations through the loading time and particularly during the development of the necking event have been determined.     

Selective adsorption of chromium(VI) from zinc(II) and other metal ions using persimmon waste gel

An adsorption gel was prepared from persimmon waste, a cellulosic material, rich in polyphenolic compounds, which exhibits a high affinity for chromium(VI). It was prepared by cross-linking persimmon waste with concentrated sulphuric acid. Adsorption tests for different metal ions such as Cr(VI), Cr(III), Fe(III), Zn(II), Cd(II) and Pb(II) from aqueous solution at pH values ranging from (pH 1 to 5) found Cr(VI) to be selectively adsorbed on the cross-linked gel over the other metal ions studied. The adsorption isotherm of Cr(VI) followed the Langmuir type of adsorption and exhibited a maximum loading capacity of 7.18 mol kg^− 1 at pH 1. Selective removal of Cr(VI) from Zn(II) was successfully demonstrated by using a column packed with the persimmon waste gel.     

A super parallel sorter using a binary neural network with AND-OR synaptic connections

This paper presents an ultra-high-speed sorter based upon a simplified parallel sorting algorithm using a binary neural network which consists both of binary neurons and of AND-OR synaptic connections to solve sorting problems at two and only two clock cycles. Our simplified algorithm is based on the super parallel sorting algorithm proposed by Takefuji and Lee. Nevertheless, our algorithm does not need any adders, while Takefuji's algorithm needs n×(n–1) analog adders of which each has multiple input ports. For an example of the simplified parallel sorter, a hardware design and its implementation will be introduced in this paper, which performs a sorting operation at two clock cycles. Both results of a logic circuit simulation and of an algorithm simulation show the justice of our hardware implementation even if in the practical size of the problem.     

A thermoresistant mutant of ribonuclease T1 having three disulfide bonds

Molecular-dynamic calculations predict that, if Tyr24 and Asn84are each replaced by a Cys residue, it should be possible toform a third disulfide bond in ribonuclease T1 (RNase T1) betweenthese residues, with only minimal conformational changes atthe catalytic site. The gene encoding such a mutant variantof RNase T1 (Tyr24 – Cys24, Asn84 – Cys84) was constructedby the cassette mutagenesis method using a chemically synthesizedgene. In order to reduce the toxic effect of the mutant enzyme(RNase T1S) on an Escherichia coli host, we arranged for theprotein to be secreted into the periplasmic space by using avector that harbors a gene for an alkaline phosphatase signalpeptide under the control of the trp promoter. The nucleolyticactivity of RNase T1S toward pGpC was approximately the sameas that of RNase T1 at 37°C (pH 7.5). Moreover, at 55°C,RNase T1S retained nearly 70% of its activity while the activityof the wild-type enzyme was reduced to <10%. RNase T1S wasalso more resistant to denaturation by urea than the wild-typeenzyme. However, unlike RNase T1, RNase T1S was irreversiblyand almost totally inactivated by boiling at 100°C for 15min.