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Abstract: We propose a novel scheme for combining two adaptation terms of affine projection algorithms with different projection orders and step-sizes. The selection of the mixing parameter that determines the performance of the proposed combination scheme is derived by the largest decrease of the mean-square deviation. The experimental results show that the proposed algorithm exhibits a fast convergence speed and a small steady-state misalignment. Moreover, the proposed algorithm achieves a low computational complexity in the steady-state. [Copyright &y& Elsevier]

Abstract: Dissolved oxygen (DO)-controlled nar promoter expression vectors were constructed, and their expression efficiency was compared with that of the T7 promoter pET22 expression vector by expressing human growth hormone (hGH), enhanced green fluorescence protein (EGFP), and β-tyrosinase in Escherichia coli cells. The nar promoter expression vector pRBS, which was engineered with a 5′-untranslated region and ribosomal binding site for the T7 promoter, expressed hGH at a rate of up to 32% of the total cellular proteins (TCP) in E. coli W3110narL−. The expression level of hGH was further enhanced, up to ∼42% of the TCP, by adding the N-terminal peptide tag of β-galactosidase to hGH, which was comparable to the expression of ∼43% of the TCP in pET-lac:hGH/BL21(DE3). A further engineered expression vector, pRBS(fnr), which coexpressed fumarate/nitrate reductase (fnr), expressed more EGFP than pET22 in BL21(DE3). In addition, recombinant β-tyrosinase was successfully expressed at a rate of up to ∼45% of the TCP in pRBS(fnr) in W3110narL−. From these results, the DO-controlled nar promoter system developed in this study can be considered a reliable and cost-effective expression system for protein production, especially in large-scale fermentation, as an alternative to the pET/BL(DE3) system. [ABSTRACT FROM AUTHOR]

Abstract: Escherichia coli has been the most widely used host for the production of recombinant proteins because it is the best characterized system in every aspect. Furthermore, the high cell density culture of recombinant E. coli has allowed production of various proteins with high yield and high productivities. Various cultivation strategies employing different host strains and expression systems have been successfully employed for the production of recombinant proteins. New strategies for strain improvement towards the goal of enhanced protein production are actively being developed based on high-throughput omics approaches such as transcriptomics and proteomics. This paper reviews recent advances in the production of recombinant proteins by high cell density culture of E. coli. [Copyright &y& Elsevier]

Abstract: We developed a giant-grain silicon (GGS) by Ni-mediated crystallization of amorphous silicon (a-Si) with a silicon-nitride (SiN x ) cap layer. Ni particles were sputtered onto the SiN x /a-Si layer and then it was annealed at around 600°C. The Ni diffuses through a SiN x cap and then forms NiSi2 crystallites in a-Si, which is able to induce crystallization. The grain size can be controlled from a few to 100μm. The grain size can be increased with increasing the cap layer thickness or by decreasing the Ni density on the SiN x . The p-channel GGS poly-Si TFT exhibited a field-effect mobility of 101cm2/Vs and a threshold voltage of −3.6V and is very stable under gate or hot carrier bias-stress. These superior performances may be due to the smooth surface of GGS poly-Si and solid-phase crystallization of a-Si. [Copyright &y& Elsevier]

Recombinant Escherichia coli (E. coli) displaying lipase on the cell surface was examined as a whole cell biocatalyst for enantioselective resolution of racemic compounds. The Pseudomonas fluorescens lipase was displayed on the cell surface of E. coli by fusing the lipase gene to the Salmonella typhimurium outer membrane protein C (OmpC) gene by C-terminal deletion–fusion strategy. The localization of truncated OmpC-lipase fusion protein was confirmed by confocal microscopy and whole cell lipase activity. As an application for enantioselective biocatalyst, whole cell bioconversion was examined using cell surface displayed lipase. When racemic ethyl 3-hydroxybutyrate, methyl mandelate and cis-3-acetoxy-4-phenylazetidin-2-one were used as substrates, (R)-3-hydroxybutyric acid, (S)-mandelic acid and (3S, 4R)-cis-3-hydroxy-4-phenylazetidin-2-one were successfully obtained with the enantiomeric excess of greater than 99%. The cell surface displayed lipase was found to be maintained without much loss of activity and selectivity during 10 repeated reactions over 120h. These results suggest that cell surface displayed lipase has a high enantioselectivity, broad substrate specificity and reusability, which makes it an excellent system for the production of various optically active compounds. [Copyright &y& Elsevier]

Growth of large-grain polycrystalline silicon has been demonstrated using silicide-mediated crystallization of amorphous silicon (a-Si) by a pulsed rapid thermal annealing (RTA). The Ni atoms in concentration of 4.6×1012/cm2 on the a-Si surface were heated at 700 °C in the RTA system for 10 s, ten times with 60 s intervals between the heat pulses. The Ni atoms on a-Si aggregate together, forming NiSi2 precipitates. The crystallization proceeds from the NiSi2 nuclei until the neighboring crystallites collide and forms distinct grain boundaries. It was found that 3.6×107 Ni atoms form a seed for metal induced crystallization and the grain size was 40 μm when the Ni density was 4.6×1012/cm2 on the a-Si. The grain size increases with decreasing metal density on a-Si. [Copyright &y& Elsevier]

The sliding wear behavior of the material of a steam generator in a nuclear power station (Inconel 600) was investigated at room temperature. Effects of the wear parameters such as material combination, sliding distance and contact stress were examined with various mating materials including 304 austenitic stainless steel, Inconel 600 and Al–Cu alloy 2011. In the prediction of the wear volume by Archard’s wear equation, the standard error range was calculated to be ±4.04×10−9 m3 and the reliability to be 71.9% for the combination of Inconel 600 and 304 stainless steel. The error range was considered to be relatively broad because the wear coefficient in Archard’s equation was assumed to be a constant, regardless of the changes in the mechanical properties during the wear. In the present study, the sliding wear behavior turned out to be influenced by the material combination; the wear volume of 304 stainless steel did not linearly increase with the sliding distance, while that of other material combinations exhibited linear increases. Based on the experimental results, the wear coefficient was modified as a function of the sliding distance. The calculation with the modified wear equation showed that the error range narrowed down to ±2.60×10−9 m3 and the reliability increased to 75.3%, compared to Archard’s original equation. [Copyright &y& Elsevier]

We studied the growth of super-grain polycrystalline silicon by silicide mediated crystallization of amorphous silicon (a-Si) using a pulsed rapid thermal annealing (RTA). The Ni particles of 4.6×1012 cm−2 were scattered onto the a-Si and then heated at various temperatures in the RTA system. The grain size was found to decrease from 41 to 26 μm with increasing crystallization temperature from 650 to 750 °C. The formation of nuclei and the grain growth rate from the nuclei have been investigated as a function of temperature. The density of NiSi2 nuclei increases from 9.47×104 to 1.89×105 cm−2 as crystallization temperature increases from 650 to 750 °C. The grain growth velocity from the nuclei was found to be 8.6×10−5 cm s−1 at 750 °C. [Copyright &y& Elsevier]

Cell-surface display allows peptides and proteins to be displayed on the surface of microbial cells by fusing them with the anchoring motifs. The protein to be displayed – the passenger protein – can be fused to an anchoring motif – the carrier protein – by N-terminal fusion, C-terminal fusion or sandwich fusion. The characteristics of carrier protein, passenger protein and host cell, and fusion method all affect the efficiency of surface display of proteins. Microbial cell-surface display has many potential applications, including live vaccine development, peptide library screening, bioconversion using whole cell biocatalyst and bioadsorption. [Copyright &y& Elsevier]

Amylose microparticles can be produced by self-assembly of amylose molecules through an amylosucrase-mediated synthesis. Here we investigated the role of short-chain fatty acids in the formation of amylose microparticles and the fate of these fatty acids at the end of the reaction. The rate of self-assembly and production yields of amylose microparticles were significantly enhanced in the presence of fatty acids. The effect was dependent on the length of the fatty acid carbon tail; butanoic acid (C4) was the most effective, followed by hexanoic acid (C6) and octanoic acid (C8). The amylose microparticles were investigated by carrying out SEM, XRD, Raman, NMR, FT-IR and DSC analysis. The size, morphology and crystal structure of the resulting amylose microparticles were comparable with those of amylose microparticles produced without fatty acids. The results indicated the carboxyl group of the fatty acid to be responsible for promoting the self-assembly of amylose chains to form microparticles. The fatty acids were eventually removed from the microstructure through the tight association of amylose double helices to form the amylose microparticles. [ABSTRACT FROM AUTHOR]

The transradial approach is increasingly used for percutaneous coronary intervention (PCI), and we therefore aimed to compare the clinical outcomes after transradial intervention (TRI) and transfemoral intervention (TFI) in all patients undergoing PCI. Among 6,973 patients enrolled in a nationwide, prospective, multicenter registry (February 2013 to September 2013), 1,860 underwent TRI (n = 1,445, 77.7%) and TFI (n = 415, 22.3%). Bleeding and major adverse cardiac events (MACE; death, myocardial infarction, revascularization, or stent thrombosis) were compared. Bleeding occurred in 42 patients (2.3%) and was significantly less likely in the TRI versus TFI group (overall cohort: 1.5% vs 4.8%, p = 0.001; propensity score-matched: n = 728, 2.7% vs 5.2%, p = 0.048). Multivariate regression revealed that TRI was negatively associated with bleeding (odds ratio 0.42, 95% CI 0.21 to 0.83, p = 0.013). MACE occurred in 152 patients (8.2%). Kaplan-Meier estimates showed higher MACE-free survival rates in the TRI versus TFI group (overall cohort: 93.3% vs 86.7%, log-rank p = 0.026; propensity score-matched: 91.8% vs 86.5%, log-rank p = 0.04). Cox proportional analysis demonstrated that TRI independently predicted improved MACE (hazard ratio 0.64, 95% CI 0.43 to 0.91, p = 0.024). In conclusion, TRI is associated with reduced bleeding rates and better clinical outcomes than TFI in all patients undergoing PCI. [ABSTRACT FROM AUTHOR]

Affine projection sign algorithm (APSA) is a useful adaptive filter for a highly correlated input signal in the presence of impulsive noise. In this study, a novel variable step-size APSA is proposed using selective input vectors to achieve both fast convergence rate and low steady-state mean-square deviation (MSD) with low computational cost. The selective input vectors and step size are chosen so as to maximize the theoretical MSD difference derived using Price׳s theorem. The simulation results show that the proposed algorithm has the fastest convergence rate and lowest steady-state MSD when compared with recent variable step-size APSAs. Moreover, it effectively reduces computational cost. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disease characterized by persistent inflammation and joint destruction. A lipid mediator (LM, namely, 17S-monohydroxy docosahexaenoic acid, resolvin D5, and protectin DX in a ratio of 3:47:50) produced by soybean lipoxygenase from DHA, exhibits anti-inflammatory activity. In this study, we determined the effect of LM on collagen antibody-induced arthritis (CAIA) in mice and receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation in RAW264.7 cells. LM effectively downregulated the expression of tartrate-resistant acid phosphatase (TRAP) and cathepsin K, inhibited osteoclast formation, and suppressed the NF-κB signaling pathway in vitro. In vivo , LM at 10 μg/kg/day significantly decreased paw swelling and inhibited progression of arthritis in CAIA mice. Moreover, proinflammatory cytokine (tumor necrosis factor-α, interleukin (IL)-6, IL-1β, IL-17, and interferon-γ) levels in serum were decreased, whereas IL-10 levels were increased following LM treatment. Furthermore, LM alleviated joint inflammation, cartilage erosion, and bone destruction in the ankles, which may be related to matrix metalloproteinase and Janus kinase (JAK)–signal transducer and activators of transcription (STAT) signaling pathway. Our findings suggest that LM attenuates arthritis severity, restores serum imbalances, and modifies joint damage. Thus, LM represents a promising therapy for relieving RA symptoms. [Display omitted] • Lipid mediators (LM) produced by soybean lipoxygenase from DHA attenuated RANKL- induced osteoclast formation. • LM improved RA symptoms and inflammatory situation in CAIA mice. • LM alleviated cartilage degradation and bone erosion in CAIA mice. • LM regulated the synovial inflammation by inhibiting the JAK/STAT signaling pathway. [ABSTRACT FROM AUTHOR]

• Lipid mediators (LM) produced by soybean lipoxygenase from DHA attenuated the inflammation in TNF-α/IFN-γ-stimulated HaCaT cells. • LM improved AD symptoms and inflammatory situation in DNCB-induced mice. • LM modulated gut microbiota diversity, and restored the microbial composition in DNCB-induced mice. Atopic dermatitis (AD) is a chronic inflammatory skin condition that primarily results from immune dysregulation. We determined the potential therapeutic benefits of lipid mediators (LM, 17S-monohydroxy DHA, resolvin D5, and protectin DX in a ratio of 3:47:50) produced by soybean lipoxygenase from DHA. The underlying molecular mechanisms involved in TNF-α/IFN-γ-stimulated HaCaT cells as well as its effect in an AD mouse model induced by DNCB in BALB/c mice were examined. The results indicated that LM effectively attenuates the production of inflammatory cytokines (IL-6 and IL-1β) and chemokines (IL-8 and MCP-1) by inhibiting the NF-κB signaling pathway in TNF-α/IFN-γ-stimulated HaCaT cells. The oral administration of LM at 5 or 10 μg/kg/day significantly reduced skin lesions, epidermal thickness, and mast cell infiltration in AD mice. Furthermore, LM reduced the production of IgE and inflammatory cytokines (TNF-α, IL-6, and IL-1β) in the serum, modulated gut microbiota diversity, and restored the microbial composition. Overall, our findings suggest that LM represents a potential therapeutic agent for improving AD symptoms through its ability to suppress inflammatory cytokines and alter the composition of gut microbiota. [ABSTRACT FROM AUTHOR]

• Self-assembly kinetics of SCGA were temperature-dependent. • Yield and particle size were decreased with increasing temperature. • Fastest formation and crystallization rates were observed at 4 and 20℃, respectively. • Nucleation enabled the formation of SCGA at 60℃. • Temperature and nucleation changed the physicochemical properties of SCGA. Self-assembly (formation and crystallization) kinetics of short-chain glucan aggregates (SCGAs) prepared at isothermal conditions (4, 20, 40, and 60℃) with or without nucleation (4℃, 1 h) were investigated. The fastest formation and crystallization rates of SCGA were observed when short-chain glucan was stored at 4℃ and 20℃, respectively. SCGA was not formed at 60℃. However, nucleation resulted in SCGA forming-ability at 60℃. Moreover, nucleation increased the yield in all temperature conditions. SCGA with nucleation decreased the crystal melting transition temperature range. All SCGAs had nanosized particles (<500 nm) with B-type crystal patterns regardless of temperature and nucleation. Consequently, self-assembly temperature and presence of nucleation step could change the physicochemical characteristics of SCGA, and manipulation of the nucleation step is expected to be an effective method to increase the yield of SCGA and produce SCGA at high temperature. [ABSTRACT FROM AUTHOR]

Background The transradial (TR) approach for percutaneous coronary intervention (PCI) is challenging and associated with failure in elderly patients. We compared the TR and transfemoral (TF) approaches in patients > 80 years with acute myocardial infarction (MI) undergoing PCI. Methods A total of 1945 (7.2%) octogenarians were enrolled from among 27,129 patients in the Korea Acute Myocardial Infarction Registry. The TR group (n = 336, 17.3%) was compared with the TF group (n = 1609, 82.7%) in the overall and propensity-matched cohorts with respect to procedural success, complications, in-hospital mortality, and one-year mortality and total major adverse cardiac event (MACE; death, MI, and revascularization) rate. Results In the overall cohort, the TR group had lower incidence of Killip class III or IV compared to the TF group. The disease extent and lesion severity were similar between groups, as was the procedural success rate (97.7% vs. 98.3%); however, in-hospital complications were significantly lower in the TR group (8.1% vs. 20.3%). In-hospital mortality was significantly lower in the TR group than the TF group (3.4% vs. 11.4%), as were the one-year mortality and total MACE (9.8% vs. 18.4% and 13% vs. 21.9%, respectively). These outcomes were consistent in the propensity-matched cohort. The TR approach was found to be a significant predictor of low in-hospital mortality (OR 0.355, 95% CI 0.139–0.907), but not of one-year mortality (OR 0.644, 95% CI 0.334–1.240). Conclusions In octogenarians with acute MI undergoing PCI, the TR approach was more effective than the TF approach as it had lower complication rate and better clinical outcomes with comparable procedural success. [ABSTRACT FROM AUTHOR]

DNA based synthetic molecular walkers are reminiscent of biological protein motors. They are powered by hybridization with fuel strands, environment induced conformational transitions, and covalent chemistry of oligonucleotides. Recent developments in experimental techniques enable direct observation of individual walkers with high temporal and spatial resolution. The functionalities of state-of-the-art DNA walker systems can thus be analyzed for various applications. Herein we review recent progress on DNA walker principles and characterization methods, and evaluate various aspects of their functions for future applications. [ABSTRACT FROM AUTHOR]

Abstract: Exocellulases play a key role in cleaving the accessible ends of cellulose molecules to release soluble glucose and cellobiose. To date, there have been no screens for exocellulase owing to assay protocol limitations, the high cost of substrates, and low activity of exocellulases compared with endocellulases. This study is the first to demonstrate direct screening for exocellulase activity using a robotic, high-throughput screening (HTS) system. Cell growth in 96-well plates was measured by monitoring optical density over 11–14h at 37°C with agitation. Fluorescence of methylumbelliferyl groups released from 4-methylumbelliferyl-β-D-cellobioside was determined using a VICTOR3 microplate reader. This new HTS system enabled activity verification of more than 104 clones per day. As a result, we obtained four exocellulases clones (CelEx-SF301, CelEx-SF309, CelEx-BR12 and CelEx-BR15) from 29,006 metagenomic fosmid clones that had previously been prepared from sweet potato field soil microbes and rumen fluid. This powerful approach could be effectively applied to screen various metagenomic resources for new enzymes. [Copyright &y& Elsevier]

Abstract: In previous studies, we identified sedative effects of Scutellaria baicalensis extracts and found that these extracts or their constituents may also have anticonvulsive effects. Wogonin is a natural product isolated from S. baicalensis, which possesses central nervous system effects such as anxiolytic and neuroprotective activities. In this study, we investigated the effects of wogonin on convulsion related behaviors, such as myorelaxation, motor coordination, and anticonvulsant effects of wogonin on chemical induced seizure and electroshock seizure in mice or rats. The effect of wogonin on membrane potential was also observed. Wogonin was intraperitoneally injected into mice or rats 30 min prior to testing. Animals treated with wogonin did not change locomotor activities as well as endurance times on the rota-rod, which indicates that wogonin did not cause a sedative and myorelaxation effect. Wogonin significantly blocked convulsion induced by pentylenetetrazole and electroshock but not convulsion induced by strychnine. Wogonin also significantly reduced the electrogenic response score, but flumazenil treatment reversed this decrease to the level of the control group. The wogonin treatment increased Cl-influx into the intracellular area as dose increased. Flumazenil and bicuculline treatment, however, inhibited the Cl− influx induced by wogonin. These results indicate that the anticonvulsive effects produced by wogonin were mediated by the GABAergic neuron. [Copyright &y& Elsevier]

Based on the previous study for the water-air mixture, the characteristics of AC electromagnetic flowmeter were investigated in the liquid metal two-phase flow. Two-phase flow experiments, encompassing bubbly to slug flow regimes, were conducted with the liquid sodium–nitrogen mixture. The simple relation ΔUTP=ΔUSP(1−α), relating flowmeter signal between single-phase flow and two-phase flow, was verified with measurements of the potential differences and the void fraction α for a bubbly flow regime in water-air loop. Whereas there was no difference in the shape of the raw signal between single-phase flow and bubbly flow, the signal amplitude of bubbly flow was greater than that of single-phase flow under the same liquid flow (sodium or water) rates, since the passage area of the liquid flow was reduced. In the case of slug flow, the phase and the amplitude of the flowmeter output showed a change in the flow characteristics around each slug bubble and the position of a slug bubble itself. Therefore, the electromagnetic flowmeter shows a good potential as a useful device for identifying the flow regimes. The void fraction can be simply measured with two electromagnetic flowmeters for a low-void fraction flow such as bubbly flow. Thus, the flowmeters can be used to measure the void fraction for a liquid sodium. [Copyright &y& Elsevier]