A User-Centered Approach to the Application of BIM in Smart Working Environments.

Considerable research has been performed on smart working environments in the architecture, engineering, and construction industry, with building information modeling considered as a critical element for implementing intelligent working systems. Although much software has been developed, a lack of understanding inhibits a user-centered approach to the application of building information modeling in architectural design offices. This study focuses on usability factors for the development of software and proposes a direction for the adoption of building information modeling in architectural design offices. This study adopts a persona method that focuses on user experience, starting with a survey conducted in two large domestic architectural offices. For developing the persona scenarios, this study provides a conceptual framework of usability, identifies user demands, and characterizes user experience. Four representative personas were developed for the representative types of users in smart working environments. The persona scenarios provide a basis that directly reflects user needs and experiences regarding the use of building information modeling software in architectural design offices. Two implications of the application of building information modeling are proposed based on the scenarios: a user-friendly working environment for smart workflows and a customized training program focusing on user experience for the use of building information modeling software.

Circular-shaped microfluidic device to study the effect of shear stress on cellular orientation.

Understanding the effects of shear stress on mammalian cells is a crucial factor for understanding a number of biological processes and diseases. Here, we show the development of a circular-shaped microfluidic device for the facile generation of shear stress gradients. With this microfluidic device, the effect of shear stress on orientation of human umbilical vein endothelial cells was studied. This microfluidic device, which enables to control the alignment of human umbilical vein endothelial cells within a microchannel, can be a valuable tool to mimic blood vessels.

Cloning, expression, and biochemical characterization of a novel GH16 ß-agarase AgaG1 from Alteromonas sp. GNUM-1.

Alteromonas sp. GNUM-1 is known to degrade agar, the main cell wall component of red macroalgae, for their growth. A putative agarase gene (agaG1) was identified from the mini-library of GNUM-1, when extracellular agarase activity was detected in a bacterial transformant. The nucleotide sequence revealed that AgaG1 had significant homology to GH16 agarases. agaG1 encodes a primary translation product (34.7 kDa) of 301 amino acids, including a 19-amino-acid signal peptide. For intracellular expression, a gene fragment encoding only the mature form (282 amino acids) was cloned into pGEX-5X-1 in Escherichia coli, where AgaG1 was expressed as a fusion protein with GST attached to its N-terminal (GST-AgaG1). GST-AgaG1 purified on a glutathione sepharose column had an apparent molecular weight of 59 kDa on SDS-PAGE, and this weight matched with the estimated molecular weight (58.7 kDa). The agarase activity of the purified protein was confirmed by the zymogram assay. GST-AgaG1 could hydrolyze the artificial chromogenic substrate, p-nitrophenyl-ß-D-galactopyranoside but not p-nitrophenyl-α-D-galactopyranoside. The optimum pH and temperature for GST-AgaG1 activity were identified as 7.0 and 40 °C, respectively. GST-AgaG1 was stable up to 40 °C (100 %), and it retained more than 70 % of its initial activity at 45 °C after heat treatment for 30 min. The K m and V max for agarose were 3.74 mg/ml and 23.8 U/mg, respectively. GST-AgaG1 did not require metal ions for its activity. Thin layer chromatography analysis, mass spectrometry, and (13)C-nuclear magnetic resonance spectrometry of the GST-AgaG1 hydrolysis products revealed that GST-AgaG1 is an endo-type ß-agarase that hydrolyzes agarose and neoagarotetraose into neoagarobiose.

Generation of uniform-sized multicellular tumor spheroids using hydrogel microwells for advanced drug screening.

Even though in vitro co-culture tumor spheroid model plays an important role in screening drug candidates, its wide applications are currently limited due to the lack of reliable and high throughput methods for generating well-defined and 3D complex co-culture structures. Herein, we report the development of a hydrogel microwell array to generate uniform-sized multicellular tumor spheroids. Our developed multicellular tumor spheroids are structurally well-defined, robust and can be easily transferred into the widely used 2D culture substrates while maintaining our designed multicellular 3D-sphere structures. Moreover, to develop effective anti-cancer therapeutics we integrated our recently developed gold-graphene hybrid nanomaterial (Au@GO)-based photothermal cancer therapy into a series of multicellular tumor spheroid co-culture system. The multicellular tumor spheroids were harvested onto a two-dimensional (2D) substrate, under preservation of their three-dimensional (3D) structure, to evaluate the photothermal therapy effectiveness of graphene oxide (GO)-wrapped gold nanoparticles (Au@GO). From the model of co-culture spheroids of HeLa/Ovarian cancer and HeLa/human umbilical vein endothelial cell (HUVEC), we observed that Au@GO nanoparticles displayed selectivity towards the fast-dividing HeLa cells, which could not be observed to this extent in 2D cultures. Overall, our developed uniform-sized 3D multicellular tumor spheroid could be a powerful tool for anticancer drug screening applications.

Effect of C-terminal domain truncation of Thermus thermophilus trehalose synthase on its substrate specificity.

The C-terminal domain of the three-domain-comprising trehalose synthase from Thermus thermophilus was truncated in order to study the effect on the enzyme's activity and substrate specificity. Compared with the wild-type (WT) enzyme, the two truncated enzymes (DM1 and DM2) showed lower maltose- and trehalose-converting activities and a different transglycosylation reaction mechanism. In the mutants, the glucose moiety cleaved from the maltose substrate was released from the enzyme and intercepted by external glucose oxidase, preventing the production of trehalose. The WT enzyme, however, retained the glucose in the active site to effectively produce trehalose. In addition, DM1 synthesized much higher amounts of mannose-containing disaccharide trehalose analog (Man-TA) than did the WT and DM2. The results suggest that the C-terminal domain in the WT enzyme is important for retaining the glucose moiety within the active site. The mutant enzymes could be used to produce Man-TA, a postulated inhibitor of gut disaccharidases.

Cloning, expression, and biochemical characterization of a GH16 ß-agarase AgaH71 from Pseudoalteromonas hodoensis H7.

An agarase gene (agaH71) was identified from Pseudoalteromonas hodoensis, an agar utilizing marine bacterium. The nucleotide sequence revealed that AgaH71 had significant homology to glycosyl hydrolase (GH) 16 agarases. agaH71 encodes a primary translation product (32.7 kDa) of 290 amino acids, including a 21-amino-acid signal peptide. The entire AgaH71 was expressed in a fused protein with glutathione-S-transferase (GST) at its N-terminal (GST-AgaH71) in Escherichia coli. Purified GST-AgaH71 had an apparent molecular weight of 59 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), which was consistent with the calculated molecular weight (58.7 kDa). Agarase activity of the purified protein was confirmed by zymogram assay. GST-AgaH71 could hydrolyze p-nitrophenyl-ß-D-galactopyranoside, but not p-nitrophenyl-α-D-galactopyranoside. The optimum pH and temperature for GST-AgaH71 were 6.0 and 45 °C, respectively. GST-AgaH71 retained more than 95 and 90 % of its initial activity at 40 and 45 °C after heat treatment for 60 min, respectively. The K m and V max for agarose were 28.33 mg/ml and 88.25 U/mg, respectively. GST-AgaH71 did not require metal ions for its activity, but severe inhibition by divalent metal ions was observed. Thin-layer chromatography (TLC) analysis, mass spectrometry, and nuclear magnetic resonance (NMR) spectrometry of the GST-AgaH71 hydrolysis products revealed that GST-AgaH71 is an endo-type ß-agarase that hydrolyzes agarose into predominantly neoagarotetraose and small proportions of neoagarobiose and neoagarohexaose.

A novel alkaliphilic xylanase from the newly isolated mesophilic Bacillus sp. MX47: production, purification, and characterization.

A newly isolated bacterial strain, Bacillus sp. MX47, was actively producing extracellular xylanase only in xylan-containing medium. The xylanase was purified from the culture broth by two chromatographic steps. The xylanase had an apparent molecular weight of 26.4 kDa with an NH(2)-terminal sequence (Gln-Gly-Gly-Asn-Phe) distinct from that of reported proteins, implying it is a novel enzyme. The optimum pH and temperature for xylanase activity were 8.0 and 40 °C, respectively. The enzyme activity was severely inhibited by many divalent metal ions and EDTA at 5 mM. The xylanase was highly specific to beechwood and oat spelt xylan, however, not active on carboxymethyl cellulose (CMC), avicel, pectin, and starch. Analysis of the xylan hydrolysis products by Bacillus sp. MX47 xylanase indicated that it is an endo-ß-1,4-xylanase. It hydrolyzed xylan to xylobiose as the end product. The K(m) and V(max) values toward beechwood xylan were 3.24 mg ml(-1) and 58.21 µmol min(-1) mg(-1) protein, respectively.