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Deep eutectic solvents (DESs) have emerged as green alternatives to conventional organic solvents for the efficient extraction of bioactive compounds. In this study, capsaicin was extracted from Capsicum annuum (C. annuum) by ultrasound-assisted extraction using strong to mild acid- and alkaline-based DESs to compare their extraction efficiency with conventional solvent. Strong alkaline-based DESs extract showed the highest capsaicin content (17.58 ± 0.28 mg/g) compared with other DESs, including acid-based DES (12.88 ± 0.11 mg/g) and ethanol (13.85 ± 0.24 mg/g) (p < 0.05) in the screening of DESs. Furthermore, optimization of alkaline-based DES extraction parameters achieved an increased capsaicin content 19.15 mg/g. Macroporous resins (SP850, XAD2, and XAD16N) were used to recover capsaicin from DES extract, and SP850 showed the highest adsorption and recovery ratio of capsaicin. Moreover, the antioxidant potency of the recovered capsaicin was confirmed using radical scavenging assays. This study provides an eco-friendly, novel, efficient extraction method for obtaining capsaicin from C. annuum. [ABSTRACT FROM AUTHOR]

Infrared (IR) transmissive polymeric materials for optical elements require a balance between their optical properties, including refractive index (n) and IR transparency, and thermal properties such as glass transition temperature (Tg). Achieving both a high refractive index (n) and IR transparency in polymer materials is a very difficult challenge. In particular, there are significant complexities and considerations to obtaining organic materials that transmit in the long-wave infrared (LWIR) region, because of high optical losses due to the IR absorption of the organic molecules. Our differentiated strategy to extend the frontiers of LWIR transparency is to reduce the IR absorption of the organic moieties. The proposed approach synthesized a sulfur copolymer via the inverse vulcanization of 1,3,5-benzenetrithiol (BTT), which has a relatively simple IR absorption because of its symmetric structure, and elemental sulfur, which is mostly IR inactive. This strategy resulted in approximately 1 mm thick windows with an ultrahigh refractive index (nav > 1.9) and high mid−wave infrared (MWIR) and LWIR transmission, without any significant decline in thermal properties. Furthermore, we demonstrated that our IR transmissive material was sufficiently competitive with widely used optical inorganic and polymeric materials. Infrared (IR) transmissive polymeric materials for optical elements require a balance between their optical and thermal properties but achieving simultaneously a high refractive index and IR transparency in the long wavelength infrared region in polymer materials is challenging. Here the authors demonstrate inverse vulcanization of 1,3,5-benzenetrithiol (BTT) to achieve a long wavelength IR transparent material without sacrificing on the thermal properties. [ABSTRACT FROM AUTHOR]

To improve the healthiness appeal of edible jelly, water-soluble extract (DP1) and polysaccharides (DP2) fractions obtained from dandelion (Taraxacum officinale) leaves were included in jellies formulation. The extracts were characterized, and their inclusion effects on jelly's quality parameters were examined. The results of monomeric composition and structural analyses revealed both fractions to contain pectic polysaccharides, with varying molar compositions of galactose (37.0–45.0%), arabinose (10.3–33.0%), glucose (1.62–11.2%), glucuronic (8.9–14.5%), and galacturonic acid (10.3–33.0%). Moreover, significant variations in their physicochemical and functional properties were observed; such differences correspondingly affected the technological properties of the Dandelion polysaccharides (DP)-fortified jellies. Seven jelly samples were prepared by incorporating 0.3 to 1% w/w of DP1 or DP2, with 0% serving as the control. Generally, the inclusion of DP significantly improved water retention, textural profile and substantially reduced syneresis of DP-jellies. While DP1-jellies displayed improved bioactivity, DP2-jellies showed higher calcium contents (up to 58.0 mg/g of jelly) in a concentration-dependent manner, as determined by in-vitro assays. The sensory evaluation results revealed that the addition of DP1 and DP2 at approximately 0.5% was acceptable and preferred to the control. The results obtained in this study confirm that polysaccharide extracts from the nutritious leaves of dandelion could be used as functional ingredients for producing antioxidant and calcium-rich jellies that meet the consumers' demands. [ABSTRACT FROM AUTHOR]

This study applied hurdle technology to achieve effective microbial inactivation, and concurrently improve the qualities of soft persimmon juice during storage. Hurdle technology applied was based on moderate temperature, ultrasonication, and pH adjustment (using ascorbic acid) as preservative factors. The inactivation effect of preservative factors and their varying combinations at different levels on Escherichia coli and Listeria monocytogenes was investigated via a stepwise approach to determine suitable inactivation conditions. The hurdle treatment for soft persimmon juice was determined based on the results of microbial inactivation and sensory test as the addition of 1% ascorbic acid combined with thermo-sonication at 50 °C for 30 min (AAUSHT). The effect of individual and hurdle treatment on juice storage quality was examined for 21 days at 4 °C. AAUSHT effectively inhibited both bacteria and fungi growth (< 0.5 log CFU/mL) in juice samples all through the storage period, as compared with other treatments (> 4 log CFU/mL). Furthermore, AAUSHT effectively reduced non-enzymatic browning, color change, and maintained apparent viscosity of juice. [ABSTRACT FROM AUTHOR]

This study aimed to improve the properties, such as tensile strength and gas barrier properties, of nylon/montmorillonite nanocomposite films for them to be better suited for packaging applications. In this study, organic/inorganic nanocomposite films were fabricated by melt compounding with a twin-screw extruder using a polyamide (m-xylene diamine 6 nylon; MXD6) as the polymer matrix and organic nanoclay (montmorillonite; MMT) as a filler. An electron beam (EB) was irradiated onto the fabricated nanocomposite film and its effects on the film properties were examined. Biaxial drawing and annealing were conducted after EB irradiation to investigate the orientation of molecular chains and crystallization. Transmission electron microscopy revealed that the clay nanoparticles were finely dispersed in the polymer matrix. Furthermore, the EB irradiation-induced polymer crosslinking was verified by measuring the gel content in the films. Finally, the thermal properties of the film were verified by differential scanning colorimetry (DSC), and the light transmittance was examined using a UV-visible spectrophotometer. Application of the sequential process of EB irradiation, biaxial drawing, and annealing on the MXD6/MMT-5 wt% nanocomposite films increased their tensile strength by 56% and decreased thermal shrinkage by 26%, with a minimal loss of the optical transparency. Increasing both nanoclay contents and draw ratios resulted in improved oxygen-gas barrier properties. In particular, the gas barrier property of the MXD6/MMT-5 wt% film approximately doubled compared with that of the untreated specimen. The thermal analysis by DSC revealed that the crystallinity decreased because of the addition of MMT and the EB irradiation. [ABSTRACT FROM AUTHOR]

Main conclusion: An improved CRISPR/Cas9 system with the Arabidopsis UBQ10 promoter-driven Cas9 exhibits consistently high mutation efficiency in Arabidopsis and M. truncatula. CRISPR/Cas9 is a powerful genome editing technology that has been applied in several crop species for trait improvement due to its simplicity, versatility, and specificity. However, the mutation efficiency of CRISPR/Cas9 in Arabidopsis and M. truncatula (Mt) is still challenging and inconsistent. To analyze the functionality of the CRISPR/Cas9 system in two model dicot species, four different promoter-driven Cas9 systems to target phytoene desaturase (PDS) genes were designed. Agrobacterium-mediated transformation was used for the delivery of constructed vectors to host plants. Phenotypic and genotypic analyses revealed that the Arabidopsis UBQ10 promoter-driven Cas9 significantly improves the mutation efficiency to 95% in Arabidopsis and 70% in M. truncatula. Moreover, the UBQ10-Cas9 system yielded 11% homozygous mutants in the T1 generation in Arabidopsis. Sequencing analyses of mutation events indicated that single-nucleotide insertions are the most frequent events in Arabidopsis, whereas multi-nucleotide deletions are dominant in bi-allelic and mono-allelic homozygous mutants in M. truncatula. Taken together, the UBQ10 promoter facilitates the best improvement in the CRISPR/Cas9 efficiency in PDS gene editing, followed by the EC1.2 promoter. Consistently, the improved UBQ10-Cas9 vector highly enhanced the mutation efficiency by four-fold over the commonly used 35S promoter in both dicot species. [ABSTRACT FROM AUTHOR]

Molten AA3003 is cooled, solidified, and rolled into a sheet by horizontal twin-roll casting. In the present investigation, this process was numerically analyzed in two dimensions by assuming the melt, the mushy state, and the solidified as an incompressible nonlinear thermo-viscous material. Coupled analyses of flow and heat transfer were repeated for updated meshes by incremental time steps until a steady state was reached. Results for different roll speeds and sheet thicknesses were obtained including the filling stage of roll gap as well as plastic deformation after solidification. Based on these results, an optimum process schedule was proposed for production of AA3003 sheet of 1 mm in thickness where the roll nip gradually decreased from 3 mm through a couple of reductions. Unstable flows with irregular contacts with the roll surface were often encountered during the analysis but settled by adjusting the roll speed or melt head. [ABSTRACT FROM AUTHOR]

Central voids or voids at the middle layer are often found in thin strips produced by twin-roll casting. These strips are in general so thin that they are unable to take a required reduction in thickness to close the voids. In the present investigation, equal-speed rolling and differential-speed rolling were compared to assess the effect of differential speed on closure of the voids by the rigid-plastic finite-element analysis. As a result, shear deformation developed in differential-speed rolling was found to reduce the reduction in thickness required for void closure. An increase in speed ratio, length of deformation zone, or friction coefficient at the interface expedited the progress in void closure. However, as the speed ratio exceeded thickness ratio, a portion of rolling power was dissipated extensively by excessive slip at the interface. Moreover, tensile stress developed which would cause cracks in the strip. [ABSTRACT FROM AUTHOR]

Conventional liquefied natural gas (LNG) vessels with membrane cargo containment systems have tank filling restrictions from 0.10 to 0.70 H (with H the internal tank height). The main reason for such restrictions is high sloshing loads around these filling depths. The new designs of prismatic LNG cargo tanks are proposed by increasing the lower chamfer length. Numerical sloshing analysis was used to optimize tank shape out of the several candidates. To validate the effectiveness of the modified tank, 1/50 scaled model tests were conducted. In these tests, 24 different irregular seaways were tested for both the conventional and the optimized tank and their statistical pressures were compared. Modified tank design was quite effective in reducing sloshing loads for a 0.30 H filling depth, and it did not significantly increase sloshing loads at other filling conditions. This study demonstrated the possibility of all filling operations for an LNG cargo containment system. [ABSTRACT FROM AUTHOR]

Metallic strips can be produced by twin-roll casting, in which the melt is cooled, solidified, and rolled to a specific thickness. In the present study, the rigid-thermoviscoplastic finite-element method was applied to the analysis of complex phenomena including melt flow, heat transfer, solidification, and plastic deformation occurring in a vertical twin-roll casting of magnesium alloy AZ31. The melt was found to be confined in rotational motions of two symmetric vortexes developed at the roll entrance, and thus only the melt near the nozzle wall became solidified and rolled to a sheet. As the nozzle thickness increased, the vortex increased in size resulting in more bifurcation and instability, which are definitely adverse to material properties of the strip. The maximum cooling rate of 600 °C/s was found at the centerline as solidification took place at the roll exit. Other findings are also discussed including roll force, roll torque, and pressure distribution, which were greatly dependent upon the plastic deformation after solidification. [ABSTRACT FROM AUTHOR]

Closure of a spherical voids in a steel slab under plane-strain deformation was investigated using the rigidplastic finite-element method. Variations in the major and minor axes of a void from finite element analysis of a void model were related to the minimum principal strain and hydrostatic stress from finite element analysis of a non-void model. The correlation curves were obtained and a method using these curves to predict the void closure progress was proposed. The method was successfully applied to deformation processes such as simple compression, forging and rolling. Since hydrostatic stress also influenced void closure, the effective strain by itself was not sufficiently capable of predicting void closure. However, the effective strain was used to predict void closure for a specific process because it reached about 0.7 in compression or forging and about 0.78 during rolling as the void completely closed. [ABSTRACT FROM AUTHOR]

Severe plastic deformation is an effective method to obtain fine or ultrafine grains in metallic materials. In the present study, a radial extrusion of a round bar was investigated for the capability of producing a thin disk by severe plastic deformation by the rigid-plastic finite-element method. Similar to the deformation mechanism in the ECAP, the shear deformation was observed to develop at the corner of the container; its magnitude increases as the radius of the corner decreases. Additional plastic deformation was obtained as the material flowed in the radial direction. However, waviness of the sheet in the radial direction and occurrence of cracking were observed at the periphery of the disk. To resolve these problems, the bottom surface of the container was conically designed in order to provide an inclination angle along the radial direction. This process was further modified to a radial extrusion of a pipe for a hollow disk or thin ring with severe-plastic deformation. [ABSTRACT FROM AUTHOR]

Voids in a slab need to be closed by plastic deformation during rolling or forging processes. However, the progress of the void closure differs for the location of a void since the stress distribution in the slab is inhomogeneous. In the present investigation, the voids were assumed to be cylindrical and aligned in the thickness direction, and the void closure at any location was attempted to be predicted during the plane-strain compression in the width direction. A series of finite element analyses were performed, and as a result relations among principal strains, minor axis and aspect ratio of the cross section of a void were obtained with which the prediction of the void closure became possible. Applications of these relations to forging and rolling processes were successfully performed. [ABSTRACT FROM AUTHOR]

The city is a kind of complex system being capable of auto-organization of its programs and adapts a principle of economy in its form generating process. A new concept of dynamic centre in urban system, called 'the programmatic moving centre', can be used to represent the successive appearances of various programs based on collective facilities and their potential values. The absolute central point is substituted by a magnetic field composed of several interactions among the collective facilities and also by the changing value of programs through time. The center moves continually into this interactive field. Consequently, we introduce mathematical methods of analysis such as 'the centroid' and 'the weighted mean' to calculate and visualize the dynamics of the urban centre. These methods heavily depend upon symmetry. We will describe and establish the moving centre from a point of view of symmetric optimization that answers the question of the evolution and successive equilibrium of the city. In order to explain and represent dynamic transformations in urban area, we tested this programmatic moving center in unstable and new urban environments such as agglomeration areas around Lausanne in Switzerland. [ABSTRACT FROM AUTHOR]

In this study, refuse plastic fuel (RPF) was copyrolyzed with low-quality coal and was gasified in the presence of a metal catalyst and steam. Some metal catalysts, such as Ni, NiO, and Mg, and mixtures of these with base promoters such as AlO and FeO were employed in the pyrolysis and gasification processes to convert the synthesis gas into more valuable fuel gas. The operating temperatures for the pyrolysis and gasification were between 700° and 1000°C. The experimental parameters were the operating temperature, catalyst type, basic promoter type, and steam injection amount. Solid fuel samples (5 g) were fed into a semibatch-type quartz tube reactor when the reactor reached the designated temperature. The synthesis gas was analyzed by gas chromatography. The use of low-quality coal as fuel in co-pyrolysis with RPF was explored. For the co-pyrolysis of RPF and low-quality coal, the effectiveness of the catalysts for fuel gas production followed the order Mg > NiO > Ni. In catalytic gasification of RPF, the addition of AlO seemed to reduce the activity of the corresponding catalysts Ni and Mg. The maximum fuel gas yield (92.6%) was attained when Mg/FeO was used in steam gasification at 1000°C. [ABSTRACT FROM AUTHOR]

Seed germination is an important character for plant growth and seed quality. We identified a rice mutant that was delayed in its germination. There, T-DNA was inserted into Oryza sativa Delayed Seed Germination 1 ( OsDSG1), causing a recessive null mutation. Overexpression of the gene enhanced seed germination. OsDSG1 is most similar to Arabidopsis AIP2, an E3 ligase targeting ABI3.Yeast two-hybrid experiments showed that our OsDSG1 binds to OsABI3, indicating that OsDSG1 is a rice ortholog of AIP2. Self-ubiquitination assay indicated that bacterially expressed OsDSG1 protein has E3 ubiquitin ligase activity. Real-time PCR analysis revealed that OsDSG1 was expressed in leaves and roots, and strongly in developing seeds. In addition to the delayed-germination phenotype, mutant plants were shorter and had greater tolerance to high-salt and drought stresses. In the osdsg1 mutant, transcript levels of ABA signaling genes and ABA responsive genes were significantly increased. By contrast, expressions of OsGAMYB and its downstream genes that encode hydrolytic enzymes were markedly reduced. These observations support that OsDSG1 is a major regulator of ABA signaling in germinating seeds. Finally, we observed that the germination rates of various rice cultivars depended upon the transcript levels of OsDSG1 and other ABA-signaling genes. [ABSTRACT FROM AUTHOR]

Precast R.C. slabs are gaining an acceptance as a structural element for bridges. One of the difficulties in the construction using the precast R.C. slabs is an introduction of longitudinal prestress. Prestressing with internal cables is not practical for the precast concrete slabs because there exist transverse joints between each precast slab. On the other hand, longitudinal prestressing with external cables can be performed in a few steps. The purpose of this study is to strengthen the precast R.C. slabs by introducing prestress with external cables. Three steel-concrete composite bridge specimens, which are prestressed with the external cables anchored on steel girders, are constructed in the laboratory. Both pre-tension and post-tension methods are used to prestress the specimens and the test results of static as well as well as fatigue loadings are reported. The results indicate that longitudinal prestress with external cables is an effective method to introduce prestress to the precast R.C. slabs. [ABSTRACT FROM AUTHOR]

In order to investigate the evolution of through-thickness texture gradients in various ferritic steel sheets, samples of a deep drawing steel, a ferritic stainless steel and a low carbon steel were deformed by cold rolling with and without application of a lubricant during the deformation process. The hot band texture of all samples examined showed notable through-thickness texture gradients. The evolution of the cold rolling texture in the ferritic stainless steel and the low carbon steel in a solution-treated state was nearly independent of the lubrication during rolling. However, in the deep drawing steel and the as-received low carbon steel, the lubrication played an important role in the formation of the through-thickness texture gradients. Whereas the samples rolled with lubrication showed uniform textures throughout the sheet thickness, in the samples rolled without lubrication pronounced shear textures were observed on the sheet surface. The evolution of these through-thickness texture gradients is discussed in terms of inhomogeneous strain states computed by an FEM model. [ABSTRACT FROM AUTHOR]

When existing simple span bridges are converted into continuous spans, rigid support conditions have to be changed to elastic supports in order to absorb and distribute the energy of horizontal motion due to an earthquake loading. However, development of additional reaction forces and stresses on the slab due to unequal displacement of the elastic supports have been overlooked. In this study, two-span continuous specimen, which is converted from two simple span structures through the “No-Joint” method, is tested and analyzed to investigate the stress distributions of the concrete slab. Durability of the concrete slab under the elastic supports is also discussed. [ABSTRACT FROM AUTHOR]

Multi-recrystallizations occurring in a steel billet during hot forging were predicted. The prediction was obtained by coupling rigid thermoviscoplastic finite element analysis and recrystallization modeling equations. The finite element analysis was preformed for nonisothermal deformation as well as heat transfer for the entire forging process. As a result, it was predicted that three or four times of recrystallizations occurred in the billet and that resulting grains varied in size for different locations. The final grain sizes at the locations in the billet were measured and compared with predicted ones. It was found that they were in good agreement. [ABSTRACT FROM AUTHOR]

A hot forging of steel usually consists of buster, blocker and finisher processes. The blocker is a transient shape to ease the metal flow in the finisher dies and it is designed by experienced engineers with rules. Recently, due to the lack of such engineers, it is necessary to develop an expert system to automate the design operations. In the present study, a rule-based expert system was developed for the blocker design of axisymmetric hot steel forging. In this paper, the major rules used in the system are summarized and the designed blockers were verified by rigid thermoviscoplastic finite element method. [ABSTRACT FROM AUTHOR]

When existing multiple simple span bridges are converted into a continuous span in order to increase the load carrying capacity by connecting each opposite ends of the simple beams, the rigid support conditions (pin and roller supports) have to be changed to elastic supports in order to absorb and distribute the energy of large horizontal motion due to earthquake loading. However, it may overlook the development of additional stress in the transverse direction of the slab due to the relative vertical displacement of the elastic support. In this study, a simple span bridge specimen of 1/6 scale is tested and analyzed by the use of F.E.M. to investigate strain increase in the transverse direction of the slab when the rigid supports are replaced by the elastic supports. Both test and analytical results exhibit a notable increase of transverse stress throughout the whole feasible range of the vertical support stiffness. [ABSTRACT FROM AUTHOR]

Mechanically adaptive electronic skins (e-skins) emulate tactition and thermoception by cutaneous mechanoreceptors and thermoreceptors in human skin, respectively. When exposed to multiple stimuli including mechanical and thermal stimuli, discerning and quantifying precise sensing signals from sensors embedded in e-skins are critical. In addition, different detection modes for mechanical stimuli, rapidly adapting (RA) and slowly adapting (SA) mechanoreceptors in human skin are simultaneously required. Herein, we demonstrate the fabrication of a highly sensitive, pressure-responsive organic field-effect transistor (OFET) array enabling both RA- and SA- mode detection by adopting easily deformable, mechano-electrically coupled, microstructured ferroelectric gate dielectrics and an organic semiconductor channel. We also demonstrate that the OFET array can separate out thermal stimuli for thermoreception during quantification of SA-type static pressure, by decoupling the input signals of pressure and temperature. Specifically, we adopt piezoelectric-pyroelectric coupling of highly crystalline, microstructured poly(vinylidene fluoride-trifluoroethylene) gate dielectric in OFETs with stimuli to allow monitoring of RA- and SA-mode responses to dynamic and static forcing conditions, respectively. This approach enables us to apply the sensor array to e-skins for bio-monitoring of humans and robotics. [ABSTRACT FROM AUTHOR]