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Recently, the application of 3D printing in the production of curved panels has increased due to the irregular shape of free-form buildings. In general, 3D printing based on additive manufacturing (AM) methods requires various supports that cause a waste of printing materials and an increase in production time. In this study, we proposed a method for printing a pair of panels that can hold each other through the minimal support connected between each panel. However, this printing method causes an additional non-productivity factor called the non-printing path for the nozzle to move between the pair of panels. Therefore, we also developed an optimal layout model that can minimize non-printing paths and used the genetic algorithm (GA) for its calculation. As a result of applying the optimization model proposed in this study through the case study, the non-printing path was reduced by 18.54% compared with that from the existing method, and the non-printing time was reduced by 34.41 h. The total production time, including non-printing time and printing time, was reduced by 3.89%, and the productivity was improved by 4.04%. The model proposed in this study is expected to minimize unproductive factors that occur in the process of manufacturing curved panels and reduce the energy consumption.

Rare sugars are regarded as functional biological materials due to their potential applications as low-calorie sweeteners, antioxidants, nucleoside analogs, and immunosuppressants. D-Allose is a rare sugar that has attracted substantial attention in recent years, owing to its pharmaceutical activities, but it is still not widely available. To address this limitation, we continuously produced D-allose from D-allulose using a packed bed reactor with commercial glucose isomerase (Sweetzyme IT). The optimal conditions for D-allose production were determined to be pH 8.0 and 60°C, with 500 g/L D-allulose as a substrate at a dilution rate of 0.24/h. Using these optimum conditions, the commercial glucose isomerase produced an average of 150 g/L D-allose over 20 days, with a productivity of 36 g/L/h and a conversion yield of 30%. This is the first report of the successful continuous production of D-allose from D-allulose by commercial glucose isomerase using a packed bed reactor, which can potentially provide a continuous production system for industrial applications of D-allose.

For using amorphous steel fibers (ASF) in Portland cement composites, the performance of ASF was evaluated by a pullout test and compared to that of a hooked-end steel fiber (HSF). The embedment length of the fiber (5.0, 8.0, and 12.5 mm), compressive strength of the mortar, and number of fibers were considered the test variables. The results showed that a single ASF had a greater maximum applied load (Pmax) than a single HSF; however, at a mortar compressive strength of 30–42 MPa, its bond strength (τmax) and pullout energy (Ef) decreased by 40.9–55.8% and 16.9–79.7%, respectively, compared to those of a single HSF. Furthermore, in the pullout failure mode, the Ef of 4 ASFs, which have a volume fraction equivalent to a single HSF, was 2.10–3.04 times higher than that of a single HSF. Based on the Ef of ASFs, an embedment length of 5–8 mm is recommended to provide the most effective ASF reinforcement effect to a mortar with a compressive strength of up to 40 MPa.

The increased awareness of electromagnetic wave hazards has prompted studies on electromagnetic shielding using conductive materials in the construction industry. Previous studies have explored the effects of the types of conductive materials and their mix proportions on the electromagnetic shielding performance; however, there has been insufficient research on the effect of the geometry of the conductive materials on the electromagnetic shielding performance. Therefore, in this study, the dependence of the electromagnetic shielding performance on the cross-sectional geometry, diameter and length of fibers was investigated. The results showed that the electromagnetic shielding performance improved when the fiber length increased or the diameter decreased, but the effect of the cross-sectional geometry of the fibers was smaller than the effect of the fiber spacing factor.

In terms of flow and compressive strength, we examined natural hwangtoh, a readily available eco-friendly material mineralogically similar to kaolin, as a possible alkali-activated binding material. The phase and molecular structures of hwangtoh before and after alkali activation were analyzed by X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (NMR). The sample prepared by mixing hwangtoh with 10 M sodium hydroxide and sodium silicate solutions at 0.45 and 0.10 by weight of hwangtoh, respectively, gave the highest compressive strength of 25.4 MPa and a flow value of 50%. The results of the XRD analysis were consistent with the results of 29 Si solid-state NMR analysis, which showed that local environments of the 29 Si nucleus in hwangtoh transformed from Q 3 (0Al) to Q 3 (1Al) and Q 4 in the amorphous phase during the alkali-activation process. The newly formed reaction products filled the pores and densified the matrix, improving the compressive strength of the alkali-activated hwangtoh paste.

15-Hydroxyeicosatetraenoic acid (HETE), as a mammalian biologically active metabolite, has anticarcinogenic effect. The conditions of producing 15-HETE from arachidonic acid by using soybean lipoxygenase were optimal at pH 8.5 and 20°C with 9 g/l arachidonic acid, 54.4 U/ml soybean lipoxygenase, and 4% methanol. Under these optimized conditions, the enzyme produced 9.5 g/l 15-HETE after 25 min, with a molar conversion yield of 99% and a productivity of 22.8 g l(-1) h(-1). To the best of our knowledge, this is the first biotechnological production of 15-HETE.

The ginsenoside compound K has pharmaceutical activities, including anti-tumor, anti-inflammatory, anti-allergic, and hepatoprotective effects. To increase the production of compound K, the α-L-arabinofuranoside-hydrolyzing α-L-arabinofuranosidase (CS-abf) and/or the α-L-arabinopyranoside-hydrolyzing β-galactosidase from Caldicellulosiruptor saccharolyticus (CS-bgal) were mixed with the β-D-glucopyranoside-hydrolyzing β-glucosidase from Sulfolobus acidocaldarius (SA-bglu). The optimum conditions for the production of ginsenoside compound K from ginsenoside Rc or Rb₂, or from major protopanaxadiol ginsenosides in ginseng root extract were determined to be pH 6.0 and 75°C with 8 mg ml⁻¹ ginsenoside Rc, 8 mg ml⁻¹ Rb₂, or 10% (w/v) ginseng root extract; and 10.5 U ml⁻¹ CS-abf or CS-bgal supplemented with 4.5 U ml⁻¹ SA-bglu, or 10.5 U ml⁻¹ CS-abf and 10.5 U ml⁻¹ CS-bgal supplemented with 4.5 U ml⁻¹ SA-bglu, respectively. Under optimum conditions, ginsenosides Rc and Rb2, and major protopanaxadiol ginsenosides in ginseng root extract were completely converted to compound K after 12, 14, and 20 h, respectively, with the respective productivities of 388, 328, and 144 mg l⁻¹ h⁻¹. This is the first report of the complete conversion of major protopanaxadiol ginsenosides to compound K.

Generally, building construction projects have a complex decision-making process because of the participation of various agents. In this situation, a final decision is arrived at by relying on subjective judgments based on the experience of project participants. For this reason, a method of assessing the objectivity of opinions is needed. In previous studies, the multi-criteria decision making method was applied to arrive at a final decision objectively, but this method has a limitation, in that the experience of each decision maker is not considered differently in the decision making process. Therefore, this study proposed a theoretical model using the S-shaped growth curve and regression analysis by building construction project type to quantitatively estimate decision-making reliability according to the experience of individual project participant`s. The developed model could be added to the Multi-criteria decision making method, and secure the objectivity and reliability of project participants` final opinion.

The objective of this study was to investigate the potential use of sand washing waste as filler for epoxy resin mortar. The mechanical properties of four series of mortars containing epoxy binder at 10, 15, 20, and 25 wt. % mixed with sand blended with sand washing waste filler in the range of 0-20 wt. % were examined. The compressive and flexural strength increased with the increase in epoxy and filler content; however, above epoxy 20 wt. %, slight change was seen in strength due to increase in epoxy and filler content. Modulus of elasticity also linearly increased with the increase in filler content, but the use of epoxy content beyond 20 wt. % decreased the modulus of elasticity of the mortar. For epoxy content at 10 wt. %, poor bond strength lower than 0.8 MPa was observed, and adding filler at 20 wt. % adversely affected the bond strength, in contrast to the mortars containing epoxy at 15, 20, 25 wt. %. The results indicate that the sand washing waste can be used as potential filler for epoxy resin mortar to obtain better mechanical properties by adding the optimum level of sand washing waste filler.

Gingival squamous cell carcinoma is a rare form of cancer that accounts for less than 10% of all head and neck cancers. Targeted therapies with natural compounds are of interest because they possess high efficacy with fewer side-effects. Methylsulfonylmethane (MSM) is an organic sulfur-containing compound with anticancer activities. The main goal of this study was to induce proliferation inhibition and apoptosis in the metastatic YD-38 cell line. MSM up-regulated expression of P21

In this study, the potential use of indigenous natural loess(Hwangtoh) as a new construction material, via alkali activation in conjunction with microwave heating, was investigated. Hwangtoh pastes with three different mix proportions of varying alkali liquid concentrations at a constant liquid-to-Hwangtoh ratio of 0.55 were prepared. Through the investigation it was found that it is possible to prepare Hwangtoh paste with 19.02 N/㎟ at tile age of 4 hours with the alkali solution of 8M NaOH and 1:4.5 mass ratio of liquefied Na₂SiO₃ at the curing temperature of 60℃ by microwave heating. The strength development at early age of tile alkali activated Hwangtoh paste specimens may be attributed to both a higher rate of reaction and moisture evaporation due to microwave heating.

The design criteria for a structural foundation with soil cement injected precast piles (SIP) indicate that the cement milk gains a conservatively high compressive strength. In addition, a certain amount of the cement milk is lost to the surrounding soil as a result of the high water-cement ratio. Furthermore, the cost increases since the material needs to be exported to the outside of the construction site to dispose of the waste soil. This study was carried out to develop a new mixing method to replace a portion of the cement milk with site soil and a cement hardener. The applicability of this method was confirmed by examining the basic physical characteristics of the new material by on-site conducting dynamic pile loading and bond capacity tests. The test results indicate that the new filling material reduced the bleeding and reduced the loss of filling material when compared to cement milk, but the compressive strength and the results of the dynamic pile loading and bond capacity tests were lower than those obtained for cement milk. However, the new filling material satisfies the standard criterion for structure design, and the economic benefits of implementing the proposed method, including saving on the amount of cement used and reducing the costs of transporting waste soil, were confirmed.

A recombinant putative lipoxygenase from Burkholderia thailandensis with a specific activity of 26.4 U mg(-1) was purified using HisTrap affinity chromatography. The native enzyme was a 75-kDa dimer with a molecular mass of 150 kDa. The enzyme activity and catalytic efficiency (k cat/K m) were the highest for linoleic acid (k cat of 93.7 s(-1) and K m of 41.5 μM), followed by arachidonic acid, α-linolenic acid, and γ-linolenic acid. The enzyme was identified as an omega-6 linoleate lipoxygenase (or a linoleate 13S-lipoxygenase) based on genetic and HPLC analyses as well as substrate specificity. The reaction conditions for the enzymatic production of 13-hydroxy-9,11(Z,E)-octadecadienoic acid (13-HODE) were optimal at pH 7.5, 25 °C, 20 g l(-1) linoleic acid, 2.5 g l(-1) enzyme, 0.1 mM Cu(2+), and 6% (v/v) methanol. Under these conditions, linoleate 13-lipoxygenase from B. thailandensis produced 20.8 g l(-1) 13-HODE (70.2 mM) from 20 g l(-1) linoleic acid (71.3 mM) for 120 min, with a molar conversion yield of 98.5% and productivity of 10.4 g l(-1) h(-1). The molar conversion yield and productivity of 13-HODE obtained using B. thailandensis lipoxygenase were 151 and 158% higher, respectively, than those obtained using commercial soybean lipoxygenase under the optimum conditions for each enzyme at the same concentrations of substrate and enzyme.

The double-site variant (C450S-N475K) l-arabinose isomerase (l-AI) from Geobacillus thermodenitrificans catalyzes the isomerization of d-galactose to d-tagatose, a functional sweetener. Using a substrate-docking homology model, the residues near to d-galactose O6 were identified as Met186, Phe280, and Ile371. Several variants obtained by site-directed mutagenesis of these three residues were analyzed, and a triple-site (F280N) variant enzyme exhibited the highest activity for d-galactose isomerization. The k cat/K m of the triple-site variant enzyme for d-galactose was 2.1-fold higher than for l-arabinose, whereas the k cat/K m of the double-site variant enzyme for l-arabinose was 43.9-fold higher than for d-galactose. These results suggest that the triple-site variant enzyme is a d-galactose isomerase. The conversion rate of d-galactose to d-tagatose by the triple-site variant enzyme was approximately 3-fold higher than that of the double-site variant enzyme for 30 min. However, the conversion yields of l-arabinose to l-ribulose by the triple-site and double-site variant enzymes were 10.6 and 16.0 % after 20 min, respectively. The triple-site variant enzyme exhibited increased specific activity, turnover number, catalytic efficiency, and conversion rate for d-galactose isomerization compared to the double-site variant enzyme. Therefore, the amino acid at position 280 determines the substrate specificity for d-galactose and l-arabinose, and the triple-site variant enzyme has the potential to produce d-tagatose on an industrial scale.

The construction industry has lower levels of improvements in technology and productivity than any other industry. One of the most useful tools to change this state of affairs is construction automation. Steel frame fabrication is a major activity in building construction, but it is difficult to employ skilled labor, as the work is hard, dangerous, and specialized. Currently, there is pressure to develop an automation system for steel frame fabrication, and this should be based on a detailed motion study to determine the required function and degree of freedom. We have developed a work breakdown structure (WBS) and modified the therblig symbol system to analyze in detail the unit motions of steel fabrication. We evaluated each motion using therblig and an analytic hierarchy process from the viewpoints of specialization, difficulty, and danger, and evaluated the overriding motion requiring automation. We propose a concept design for an automation system for steel frame fabrication that will be very helpful in automating steel frame fabrication.