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To develop the technology for CO2 sequestration, the free and immobilized carbonic anhydrase treatment was performed. The amount of dissolved CO2 was increased by 3-fold after enzyme treatment of 5 ppm, and the amount of calcium carbonate increased linearly as the CaCl2 was increased to 100 mM. To immobilize the carbonic anhydrase, an aluminum oxide carrier surface was functionalized with octadecyltrichlorosilane, 1H,1H,2H,2H-perfluoroctyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyl triethoxysilane, chlorotrimethylsilane 3-cyanopropyltrichlorosilane or 3-glycidyloxypropyltriethoxysilane. The best effect among these substances was revealed with 3-aminopropyltriethoxysilane; the efficacy of the immobilized carbonic anhydrase was at over 99%, and even when it was repeatedly used up to 40 times, the efficacy of the immobilized enzyme was more than 80%. The optimal conditions for the immobilized enzyme were 60oC and pH 7.0.

The gene encoding 1,4-β-endoglucanase KRICT PC-001 (1.722 bp; 573 aa) was revealed by a full-length sequence analysis of the bacterium Paenibacillus terrae HPL-003 (KCTC 11987BP) isolated from the soil on Gara Mountain in Korea (CP003107). The molecular weight of the enzyme was estimated as 62 kDa by SDS-PAGE analysis. Endoglucanase KRICT PC-001 contains a catalytic domain of the glycosyl hydrolase family 5 (GH5) and a carbohydrate-binding module X2 (CBM X2). The soluble fraction of the recombinant protein was overexpressed with the pGEX-fusion vector in Escherichia coli BL21 (DE3) and purified using glutathione S-transferase column. The recombinant protein was digested with Factor Xa and eluted from a benzamidine column. Carboxymethyl cellulose was used as a substrate for the enzyme activity analysis. Endoglucanase KRICT PC-001 exhibited a maximum specific activity of 589 U/mg of protein at a temperature of 50°C and pH 5.0.

A natural compound plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) was isolated from the leaves of Plumbago auriculata and found to inhibit the enzyme, 8-amino-7-oxononanoate synthase (AONS, also known as 7-keto-8-aminopelargonate synthase, KAPAS) an IC 50 of 2.1 μM in vitro . Biotin supplement significantly rescued the plant injury caused by the plumbagin treatment, and this result confirmed the target site, AONS. Foliar application of 1000 ∼ 2000 μg/mL plumbagin in a greenhouse condition showed lethal activity against eight species of weeds, containing three grass species of Sorghum bicolor , Echinochloa crus-galli , Digitaria sanguinalis and five broad leaf species of Solanum nigrum , Aeschynomene indica , Abutilon avicennae , Xanthium strumarium , Calystegia japonica . Field trial of foliar application with plumbagin 2000 μg/mL have successfully controlled 10 ∼ 15 leaf-stages and 2 ∼ 3 m vine lengths of Sicyos angulatus at the natural habitats around riparian zone in the Nam-Han River in Korea. Visual symptom of desiccation might be induced by the physiological cellular leakage which was significantly dose dependent on the plumbagin treatment regardless of light.

Background Periostin is a matricellular protein, and its synthesis in airway epithelial cells and lung fibroblasts is induced by interleukin (IL)-4 and IL-13. The significance of periostin as a biomarker of TH2-induced airway inflammation, and (importantly) as a measure of the response to TH2-targeted therapy, has recently been emphasized. We explored the relationship between periostin and airway hyperresponsiveness (AHR) in asthmatic children. Methods The study included 83 children aged 6–15 years in an asthmatic group (n = 54) and healthy controls (n = 29). We measured the periostin levels in serum and performed methacholine and mannitol provocation challenges. The responses to mannitol were expressed as the provocative dose causing a 15% fall in the FEV1 (the PD15 dose). Results Of the 54 subjects with asthma, all had positive methacholine bronchial provocation test (BPT) results and 38 had positive mannitol BPT results. Children with asthma had significantly higher periostin levels than controls [76.0 (65.0–91.8) vs 71.0 (57.5–80.0) ng/mL; P = 0.017]. Periostin levels were significantly correlated with both the methacholine PC20 and mannitol PD15 values. Conclusion Serum levels of periostin, a new biomarker induced by IL-13, were higher in asthmatic children, and were associated with AHR to methacholine and mannitol.

The peak-to-average power ratio (PAPR) statistics in a multi-band orthogonal frequency division multiplexing (MB-OFDM) system, which is being considered as a possible candidate for the IEEE 802.15 high rate alternative PHY, is analysed. In the MB-OFDM system, high PAPR is introduced by a conjugate symmetric input to inverse fast Fourier transform. To alleviate this problem, the selective mapping and partial transmit sequence are introduced for the MB-OFDM signals and the performance comparisons between two methods are discussed.

The dynamic response of liquid storage tank, including the hydrodynamic interactions, subjected to earthquake excitations is studied by the combinations of boundary element method and finite element procedure in this paper. The tank wall and inviscid fluid domain are treated as two substructures of the total system-coupled through the hydrodynamic pressures. The boundary element method is employed to determine the hydrodynamic pressures associated with small amplitude excitations and negligible surface wave effects in fluid domain which are expressed as the frequency-dependent terms related with the natural vibration modes of elastic tank alone. These terms are incorporated into the finite element formulation of elastic tank in frequency domain and the generalized displacements are computed by synthesizing their complex frequency response using Fast-Fourier Transform procedure. Thus, the hydrodynamic interactions between the elastic flexible tank wall and the fluid are then solved. To demonstrate the accuracy and validity of the solution procedure developed herein, numerical examples are analyzed. Good correlations between the computed results with the referenced solutions in literature can be noted. The effects of fluid compressibility and tank flexibility are also evaluated in this work. Finally, the dynamic response of liquid storage tank due to seismic excitations is also analyzed.

The fluid flow processes in a squeeze film having one porous bounding wall are analyzed. The analysis takes account of velocity slip at the surface of the porous medium as well as of the coupled flows in the squeeze film and the porous material. Results are presented for the load-carrying capacity of the squeeze film and its thickness–time relation. The results show that porous media are effective in diminishing the response times of squeeze films. In particular, substantially faster response can be attained by the use of porous materials which accentuate velocity slip.