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Microcarriers with a high surface-to-volume ratio within bioreactor systems have been used for several decades to develop scalable and cost-effective processes for cultivating adherent cells to produce therapeutic cells, vaccines, and proteins. However, the agitation equipment in bioreactors, which is essential for suspending microcarriers and maintaining homogeneous culture conditions, generates high shear forces that adversely affect the growth of adherent cells. Fluidized bed reactors (FBRs), which are capable of suspending particles solely with liquid flow without an impeller, could provide a solution for these issues. Typical FBRs with cylindrical columns encounter difficulties in controlling the fluidized bed, due to a narrow flow rate range for fluidization and changes in the characteristics of microcarriers as cells grow, despite the advantages of low-shear forces. This leads to the failure of microcarrier fluidization and reduced efficiency of the microcarrier-based cell culture. In this study, we demonstrate a newly developed funnel-type fluidized bed reactor (FFBR) system with enhanced culture stability and evaluated its performance by culturing mouse fibroblasts (L929) and human mesenchymal stem cells. The FFBR exhibits stable operation over the entire culture period, unlike the FBRs with cylindrical columns. The cell density per culture area achieved with the FFBR was comparable to that obtained using the two-dimensional plastic culture system for both cell types. The FFBR is a useful tool for the expansion of adherent cells due to its stability and scalability, making it suitable for research, development, and manufacturing for therapeutic applications. [ABSTRACT FROM AUTHOR]

3D printing is widely used across various domains and has advanced to the extent of being employed in crafting rocket parts. This study utilized ultrasound-based nondestructive testing to examine the ultrasound propagation with 3D-printed plates. The research focused on evaluating anisotropy due to filament orientation of FDM-based printed specimens and velocity variations based on the propagation of ultrasonic waves. Plate specimens with [0], [0, 90], [0, 60, 120] alignment were assessed using the pitch-catch method. Python was used to analyze the waveform in order to obtain the velocity of ultrasound. Results revealed that ultrasound propagates mainly along the filament's output direction. In plate specimens, ultrasound velocity and amplitudes depend on the propagation direction. As a result, using ultrasound can be used to evaluate the anisotropy of 3D-printed plates. [ABSTRACT FROM AUTHOR]

The importance of a single-use bioreactor (SUB) is continuously increasing in research and industrial fields for biopharmaceutical production. In this study, a newly developed SUB system, the CELBIC® system, applied with the unique agitation method is introduced, and its physical properties and biological applications are evaluated. The mixing time was in the range of 11.0–129.0 s, and the volumetric mass transfer coefficient, kLa, measured through surface aeration, was in the range of 2.7–15.5 h−1 at a working volume of 1–10 L. Biological evaluations using two Chinese hamster ovary (CHO) cell lines, CHO-DG44 and CHO-S cell, were carried out in the CELBIC® systems in 1 and 50 L scales, showing similar cell culture performance as that from stirred tank-type bioreactors. These results support the CELBIC® system as a new SUB system applicable to cell cultures for biopharmaceutical production. [ABSTRACT FROM AUTHOR]

Fe‒S cluster-harboring enzymes, such as carbon monoxide dehydrogenases (CODH), employ sophisticated artificial electron mediators like viologens to serve as potent biocatalysts capable of cleaning-up industrial off-gases at stunning reaction rates. Unraveling the interplay between these enzymes and their associated mediators is essential for improving the efficiency of CODHs. Here we show the electron mediator-interaction site on ChCODHs (Ch, Carboxydothermus hydrogenoformans) using a systematic approach that leverages the viologen-reactive characteristics of superficial aromatic residues. By enhancing mediator-interaction (R57G/N59L) near the D-cluster, the strategically tailored variants exhibit a ten-fold increase in ethyl viologen affinity relative to the wild-type without sacrificing the turn-over rate (kcat). Viologen-complexed structures reveal the pivotal positions of surface phenylalanine residues, serving as external conduits for the D-cluster to/from viologen. One variant (R57G/N59L/A559W) can treat a broad spectrum of waste gases (from steel-process and plastic-gasification) containing O2. Decoding mediator interactions will facilitate the development of industrially high-efficient biocatalysts encompassing gas-utilizing enzymes. Carbon monoxide dehydrogenases (CODH) employ artificial electron mediators like viologens for biocatalysis, but little is known about the interaction between the mediators and the enzyme. Here, the authors discover the critical site for viologen interactions at the D-cluster of Carboxydothermus hydrogenoformans CODH2 via alanine mutations and crystallography, and report variants with increased ethyl viologen affinity. [ABSTRACT FROM AUTHOR]

This paper presents a digital microfluidic (DMF) platform based on a printed circuit board (PCB) for droplet mixing. Mixing droplets without a top cover plate is important for bio-chemical analysis. For this reason, a more efficient mixing method is required especially for mixing a viscous liquid droplet in an open surface. Here, to improve the performance of droplet mixing, we propose the integration of an acoustically oscillating bubble to an electrowetting-on-dielectric (EWOD) chip, which can generate microstreaming inside the droplet. Firstly, an EWOD chip integrated with through-holes for bubble trapping was designed and fabricated through PCB fabrication. This PCB manufacturing technology helps to place more electrodes in the limited chip size. Secondly, we developed the custom-made circuit and interface to individually control multiple actuators (including EWOD actuation and acoustic excitation). Finally, an operation test was conducted to evaluate the capability of not only droplet transportation but also mixing on an open surface. The proposed PCB-based DMF platform for bubble-induced droplet mixing was experimentally verified and expected to make DMF chips more efficient when used for clinical point-of-care diagnostic applications. [ABSTRACT FROM AUTHOR]

High‐performance organic neuromorphic devices with miniaturized device size and computing capability are essential elements for developing brain‐inspired humanoid intelligence technique. However, due to the structural inhomogeneity of most organic materials, downscaling of such devices to nanoscale and their high‐density integration into compact matrices with reliable device performance remain challenging at the moment. Herein, based on the design of a semicrystalline polymer PBFCL10 with ordered structure to regulate dense and uniform formation of conductive nanofilaments, we realize an organic synapse with the smallest device dimension of 50 nm and highest integration size of 1 Kb reported thus far. The as‐fabricated PBFCL10 synapses can switch between 32 conductance states linearly with a high cycle‐to‐cycle uniformity of 98.89% and device‐to‐device uniformity of 99.71%, which are the best results of organic devices. A mixed-signal neuromorphic hardware system based on the organic neuromatrix and FPGA controller is implemented to execute spiking‐plasticity‐related algorithm for decision-making tasks. Designing high performance organic neuromorphic devices remains a challenge. Here, Liu et al. report the development of an organic synapse based on a semicrystalline polymer PBFCL10 with device dimension of 50 nm and integration size of 1 Kb and a mixed‐signal neuromorphic hardware system based on the organic neuromatrix and FPGA controller for decision‐making tasks. [ABSTRACT FROM AUTHOR]

Colon-targeted oral drug delivery systems comprising nanoparticles and microparticles have emerged as promising tools for the treatment of ulcerative colitis (UC) because they minimize side effects and maximize the local drug concentration. Dexamethasone sodium phosphate (DSP) is a potent anti-inflammatory glucocorticoid used for the treatment of UC. However, it remains a rather short-term treatment option owing to its side effects. In the present study, we developed the alginate gel encapsulating ionically bridged DSP-zinc-poly(lactic-co-glycolic acid) (PLGA) nanocomplex (DZP-NCs-in-microgel) for the oral local treatment of UC. The successful encapsulation of DSP-zinc-PLGA nanocomplex (DZP-NCs) in alginate microgel was confirmed by SEM imaging. The prepared gel released DZP-NCs in the stimulated intestinal fluid and dampened the release of DSP in the upper gastrointestinal tract. Furthermore, DZP-NCs-in-microgel alleviated colonic inflammation in a mouse model of dextran sodium sulfate-induced colitis by relieving clinical symptoms and histological marks. Our results suggest a novel approach for the oral colon-targeted delivery of dexamethasone sodium phosphate for the treatment of UC. [ABSTRACT FROM AUTHOR]

A quantitative single-molecule tip-enhanced Raman spectroscopy (TERS) study at room temperature remained a challenge due to the rapid structural dynamics of molecules exposed to air. Here, we demonstrate the hyperspectral TERS imaging of single or a few brilliant cresyl blue (BCB) molecules at room temperature, along with quantitative spectral analyses. Robust chemical imaging is enabled by the freeze-frame approach using a thin Al2O3 capping layer, which suppresses spectral diffusions and inhibits chemical reactions and contamination in air. For the molecules resolved spatially in the TERS image, a clear Raman peak variation up to 7.5 cm−1 is observed, which cannot be found in molecular ensembles. From density functional theory-based quantitative analyses of the varied TERS peaks, we reveal the conformational heterogeneity at the single-molecule level. This work provides a facile way to investigate the single-molecule properties in interacting media, expanding the scope of single-molecule vibrational spectroscopy studies. Tip-enhanced vibrational spectroscopy at room temperature is complicated by molecular conformational dynamics, photobleaching, contaminations, and chemical reactions in air. This study demonstrates that a sub-nm protective layer of Al2O3 provides robust conditions for probing single-molecule conformations. [ABSTRACT FROM AUTHOR]

Solar hydrogen production is one of the ultimate technologies needed to realize a carbon-neutral, sustainable society. However, an energy-intensive water oxidation half-reaction together with the poor performance of conventional inorganic photocatalysts have been big hurdles for practical solar hydrogen production. Here we present a photoelectrochemical cell with a record high photocurrent density of 19.8 mA cm−2 for hydrogen production by utilizing a high-performance organic–inorganic halide perovskite as a panchromatic absorber and lignocellulosic biomass as an alternative source of electrons working at lower potentials. In addition, value-added chemicals such as vanillin and acetovanillone are produced via the selective depolymerization of lignin in lignocellulosic biomass while cellulose remains close to intact for further utilization. This study paves the way to improve solar hydrogen productivity and simultaneously realize the effective use of lignocellulosic biomass. While light-driven water splitting offers a means to produce renewable H2 fuel, water oxidation limits performances and yields low-value products. Here, authors demonstrate a photoelectrochemical cell that converts lignocellulosic biomass into valuable products alongside H2. [ABSTRACT FROM AUTHOR]

Due to its superior ability in controlling pharmaceutical activity, the installation of difluoromethyl (CF2H) functionality into organic molecules has been an area of intensive research. In this context, difluoromethylation of C−C π bonds mediated by a CF2H radical have been pursued as a central strategy to grant access to difluoromethylated hydrocarbons. However, early precedents necessitate the generation of oxidative chemical species that can limit the generality and utility of the reaction. We report here the successful implementation of radical hydrodifluoromethylation of unsaturated C−C bonds via an electroreductively triggered two-pronged approach. Preliminary mechanistic investigations suggest that the key distinction of the present strategy originates from the reconciliation of multiple redox processes under highly reducing electrochemical conditions. The reaction conditions can be chosen based on the electronic properties of the alkenes of interest, highlighting the hydrodifluoromethylation of both unactivated and activated alkenes. Notably, the reaction delivers geminal (bis)difluoromethylated products from alkynes in a single step by consecutive hydrodifluoromethylation, granting access to an underutilized 1,1,3,3-tetrafluoropropan-2-yl functional group. The late-stage hydrodifluoromethylation of densely functionalized pharmaceutical agents is also presented. The installation of difluoromethylene groups into bio-relevant molecules allows access to important scaffolds, but existing methods to do so often rely on oxidative chemical species that can hamper reactivity. Here, radical hydrodifluoromethylation with a wide range of unsaturated C–C bonds is achieved via an electroreductive two-pronged approach, granting access to a variety of difluoromethylated organic molecules. [ABSTRACT FROM AUTHOR]

The endoplasmic reticulum (ER)-mitochondria contact site (ERMCS) is crucial for exchanging biological molecules such as phospholipids and Ca2+ ions between these organelles. Mitoguardin-2 (MIGA2), a mitochondrial outer membrane protein, forms the ERMCS in higher eukaryotic cells. Here, we report the crystal structures of the MIGA2 Lipid Droplet (LD) targeting domain and the ER membrane protein VAPB bound to the phosphorylated FFAT motif of MIGA2. These structures reveal that the MIGA2 LD targeting domain has a large internal hydrophobic pocket that accommodates phospholipids and that two phosphorylations of the FFAT motif are required for tight interaction of MIGA2 with VAPB, which enhances the rate of lipid transport. Further biochemical studies show that MIGA2 transports phospholipids between membranes with a strong preference for binding and trafficking phosphatidylserine (PS). These results provide a structural and molecular basis for understanding how MIGA2 mediates the formation of ERMCS and facilitates lipid trafficking at the ERMCS. The ER-mitochondria contact sites are crucial for exchanging phospholipids. Here, Kim et al. present crystal structures of mitoguardin-2 (MIGA2) which reveal that MIGA2 directly binds phospholipids and transfers them between the ER and mitochondria. [ABSTRACT FROM AUTHOR]

Ultra-multiplexed fluorescence imaging requires the use of spectrally overlapping fluorophores to label proteins and then to unmix the images of the fluorophores. However, doing this remains a challenge, especially in highly heterogeneous specimens, such as the brain, owing to the high degree of variation in the emission spectra of fluorophores in such specimens. Here, we propose PICASSO, which enables more than 15-color imaging of spatially overlapping proteins in a single imaging round without using any reference emission spectra. PICASSO requires an equal number of images and fluorophores, which enables such advanced multiplexed imaging, even with bandpass filter-based microscopy. We show that PICASSO can be used to achieve strong multiplexing capability in diverse applications. By combining PICASSO with cyclic immunofluorescence staining, we achieve 45-color imaging of the mouse brain in three cycles. PICASSO provides a tool for multiplexed imaging with high accessibility and accuracy for a broad range of researchers. Ultra-multiplexed fluorescence imaging is currently difficult. Here the authors report PICASSO which enables 15-colour imaging of spatially overlapping proteins in a single-round of imaging; they combine it with cyclic immunofluorescence to achieve 45-colour imaging of the mouse brain in 3 cycles. [ABSTRACT FROM AUTHOR]

Pparg, a nuclear receptor, is downregulated in basal subtype bladder cancers that tend to be muscle invasive and amplified in luminal subtype bladder cancers that tend to be non-muscle invasive. Bladder cancers derive from the urothelium, one of the most quiescent epithelia in the body, which is composed of basal, intermediate, and superficial cells. We find that expression of an activated form of Pparg (VP16;Pparg) in basal progenitors induces formation of superficial cells in situ, that exit the cell cycle, and do not form tumors. Expression in basal progenitors that have been activated by mild injury however, results in luminal tumor formation. We find that these tumors are immune deserted, which may be linked to down-regulation of Nf-kb, a Pparg target. Interestingly, some luminal tumors begin to shift to basal subtype tumors with time, down-regulating Pparg and other luminal markers. Our findings have important implications for treatment and diagnosis of bladder cancer. PPARg is differentially expressed in bladder cancer subtypes. Here, the authors show in mice that when an activated form of PPARg is expressed in basal bladder cells tumours do not form, however in the presence of injury the basal cells differentiate into luminal cells. [ABSTRACT FROM AUTHOR]

The poor catalyst stability in acidic oxidation evolution reaction (OER) has been a long-time issue. Herein, we introduce electron-deficient metal on semiconducting metal oxides-consisting of Ir (Rh, Au, Ru)-MoO3 embedded by graphitic carbon layers (IMO) using an electrospinning method. We systematically investigate IMO's structure, electron transfer behaviors, and OER catalytic performance by combining experimental and theoretical studies. Remarkably, IMO with an electron-deficient metal surface (Irx+; x > 4) exhibit a low overpotential of only ~156 mV at 10 mA cm−2 and excellent durability in acidic media due to the high oxidation state of metal on MoO3. Furthermore, the proton dissociation pathway is suggested via surface oxygen serving as proton acceptors. This study suggests high stability with high catalytic performance in these materials by creating electron-deficient surfaces and provides a general, unique strategy for guiding the design of other metal-semiconductor nanocatalysts. The poor catalyst stability for oxygen evolution in acidic media has been a long-time issue. Here, authors demonstrate iridium on MoO3 exhibits a low overpotential for oxygen evolution and excellent durability in acidic media due to the high oxidation state of iridium metal on MoO3. [ABSTRACT FROM AUTHOR]

Attraction effects arise when a comprehender erroneously retrieves a distractor instead of a target item during memory retrieval operations. In Korean, considerable processing difficulties occur in the agreement relation checking between a subject and an honorific-marked predicate when an intervening distractor carries a non-honorific feature. We investigate how attraction effects are managed during the processing of Korean subject-predicate honorific agreement by two Korean-speaking groups with different language use experience backgrounds: college students and airline workers. Results showed that both groups demonstrated stable knowledge of the honorific agreement in the acceptability judgment task. In the self-paced reading task, the airline group, who used honorifics extensively in their workplace, was less affected by the attraction effect than the student group. Our findings suggest that long-term language use experience can modulate how language users manage potential influence from attraction effects in real-time sentence processing. [ABSTRACT FROM AUTHOR]

The aim of this study is to propose a new detection method for determining the damage locations in pile foundations based on deep learning using acoustic emission data. First, the damage location is simulated using a back propagation neural network deep learning model with an acoustic emission data set acquired from pile hit experiments. In particular, the damage location is identified using two parameters: the pile location (PL) and the distance from the pile cap (DS). This study investigates the influences of various acoustic emission parameters, numbers of sensors, sensor installation locations, and the time difference on the prediction accuracy of PL and DS. In addition, correlations between the damage location and acoustic emission parameters are investigated. Second, the damage step condition is determined using a classification model with an acoustic emission data set acquired from uniaxial compressive strength experiments. Finally, a new damage detection and evaluation method for pile foundations is proposed. This new method is capable of continuously detecting and evaluating the damage of pile foundations in service. [ABSTRACT FROM AUTHOR]

The acoustic emission (AE) technique has been widely used to monitor damage for concrete structures in underground space. To analyze the damage status successfully, it is important to understand the characteristics of AE parameters during failure for concrete-based-underground structures. The AE parameters are related to the target material characteristics (i.e., sand content ratio) and failure steps (i.e., stress levels) of concrete specimens. In this study, the concrete specimens were prepared with different sand content ratio. Uniaxial compressive tests were performed for the specimens with AE monitoring to investigate the characteristics of AE parameters in the time domain (i.e., count, energy, and amplitude) and frequency domain (i.e., initial frequency and peak frequency). The experimental results were analyzed with the sand content ratio and failure step (1–4) in order to determine the suitable AE parameter as a monitoring index. The most suitable parameter was shown as the cumulative energy parameter of AE with high sensitivity. [ABSTRACT FROM AUTHOR]

This paper presents a scalable method of near duplicate image detection based on Gist-PCA (principal component analysis) hashing. While most of transform coding methods have been interested in nearest neighbor search with applications to similar image search, we solve a range search problems found in near duplicate detection problems. At first, we argue that the PCA hashing of the Gist descriptor is adequate for near duplicate image detection. Then, we decompose the Gist-PCA binary code into a hash key and a residual binary code for scalability into large-scale datasets. In addition, a multi-block approach is incorporated into the method to deal with strong variations, such as image cropping and border framing. Experimental results show that the proposed method is more accurate and faster than the real-valued Gist descriptor and other nearest neighbor search methods. [ABSTRACT FROM AUTHOR]

This study investigated whether Chinese-Korean bilinguals can use structure-based information to interpret Korean sentences containing floating numeral quantifiers during online processing. A numeral quantifier in Korean can be stranded from its modified noun through scrambling as long as the quantifier forms a constituent with the noun. For Chinese-Korean bilinguals, acquiring this structural knowledge gives rise to a learnability problem because this ability cannot be derived from the L1, not easily induced from Korean input and is not obtained through classroom instruction. In acceptability judgment, highly proficient Chinese-Korean bilinguals demonstrated target-like knowledge of this structural constraint. Results from a self-paced reading task showed that the bilinguals showed sensitivity to the violation of the mismatch between an NQ and its modified NP, both in local and non-local dependency conditions. Our findings suggest that structure-based processing is possible for highly proficient bilinguals even when the target structure is not instantiated in bilinguals’ L1. [ABSTRACT FROM AUTHOR]

Purpose: Segmental bioimpedance analysis (BIA) can identify fluid volume changes in the arms of patients on hemodialysis (HD) after vascular access surgery. We investigated whether the difference in fluid volumes between the arms of the patients using segmental BIA is associated with vascular access outcome.Methods: Body composition measurements were taken for 127 patients on HD with segmental, multi-frequency BIA equipment (InBody 1.0, Biospace Co. Ltd, Seoul, Korea). The difference in fluid volume between the arms of the patients was calculated from the fluid volume of the arm with the vascular access minus that of the other. The primary outcome was the loss of vascular access patency within 3 months of BIA measurement.Results: The median absolute and relative inter-arm fluid volume differences were 150 ml [interquartile range (IQR) 90-250 ml] and 9.6% (IQR 4.9-14.4%), respectively. Within 3 months of BIA measurement, 38 patients (30.0%) experienced vascular access failure. When the patients were divided into three groups based on the tertiles of relative inter-arm fluid volume differences (lowest tertile: < 6.8%; middle tertile: 6.8-12.7%; highest tertile: > 12.7%), greater difference in relative inter-arm fluid volume differences was associated with higher vascular access failure rates (14 vs. 28 vs. 48%, p value for trend across tertiles = 0.003).Conclusions: We conclude that segmental BIA may be used as a tool that can predict vascular access failure in patients on HD by calculating the relative difference in fluid volume between the arms of the patients with and without vascular access. [ABSTRACT FROM AUTHOR]

Purpose: Hemodialysis vascular access dysfunction, mostly attributed to neointimal hyperplasia, is a major cause of morbidity and hospitalization in patients on hemodialysis. It has been reported that prostaglandin I has pleiotropic effects including anti-platelet, vasodilating, anti-inflammatory, and anti-atherogenic properties. In addition, several studies have shown that prostaglandin I can inhibit neointimal formation after vascular injury. This study aimed to investigate the effects of beraprost sodium, an oral synthetic analog of prostaglandin I, on vascular access patency in patients on hemodialysis who experienced primary hemodialysis vascular access failure. Methods: Fifty-five patients with end-stage renal disease who were on hemodialysis were prospectively selected for this study. Twenty-three patients were assigned to be treated with 120 µg/day of beraprost sodium, while remaining patients ( n = 32) were assigned to a control group. The primary outcome was primary unassisted vascular access patency at 2 years. Results: The incidence of primary unassisted patency at 2 years was 83% in the beraprost sodium group and 38% in the control group ( p = 0.001). Analysis of covariables indicated that this effect occurred mainly as a result of beraprost sodium administration. No life-threatening adverse event or severe bleeding was recorded in any of the groups. Conclusions: Our data indicated that an oral prostaglandin I analog, beraprost sodium, is effective and safe for the maintenance of vascular access patency in patients on hemodialysis with primary vascular access failure. [ABSTRACT FROM AUTHOR]

The interleukin (IL)-1 family is the largest family of interleukins. Eleven members of the IL-1 family of ligands are intracellular molecules, except a single isoform of an IL-1 receptor antagonist (IL-1Ra; also known as IL-1RN), which contains a signal peptide at the N-terminus for effective secretion. The inflammasome is a complex of intracellular molecules that is responsible for the processing of IL-1β and IL-18, whereas the remaining IL-1 family members, including IL-1α, are processed in an inflammasome caspase-1-independent pathway. Among the eleven members of the IL-1 family ligands, precursor IL-1α, IL-1β, and IL-33 have comparatively long pro-peptides of approximately 110 amino acid residues at the N-terminus. However, the other IL-1 members, except for IL-37 (also known as IL-1F7), have relatively short propeptides with fewer than 40 amino acid residues at the N-terminus. Most cytokines, including interferons and interleukins, possess a hydrophobic signal sequence for secretion. Therefore, soluble cytokines readily act on cell surface receptors immediately after their release from cells. Unlike other cytokine families, IL-1 family ligands exhibit two-step regulation: transcriptional induction at the mRNA level and post-translational modification at the protein level because of the lack of a hydrophobic signal sequence at the N-terminus. Various processing enzymes involved in the activation of intracellular IL-1 family cytokines likely provide effective immune regulation to protect the host from infections. In this review, we describe all eleven IL-1 family ligand processing enzymes, mature ligand functions, and mode of receptor conformation. [ABSTRACT FROM AUTHOR]

Underground compressed air energy storage (CAES) in lined rock caverns (LRCs) provides a promising solution for storing energy on a large scale. One of the essential issues facing underground CAES implementation is the risk of air leakage from the storage caverns. Compressed air may leak through an initial defect in the inner containment liner, such as imperfect welds and construction joints, or through structurally damaged points of the liner during CAES operation for repeated compression and decompression cycles. Detection of the air leakage and identification of the leakage location around the underground storage cavern are required. In this study, we analyzed the displacement (or strain) monitoring method to detect the mechanical failure of liners that provides major pathways of air leakage using a previously developed numerical technique simulating the coupled thermodynamic and geomechanical behavior of underground CAES in LRCs. We analyzed the use of pressure monitoring to detect air leakage and characterize the leakage location. From the simulation results, we demonstrated that tangential strain monitoring at the inner face of sealing liners could enable one to detect failure. We also demonstrated that the use of the cross-correlation method between pressure history data measured at various sensors could identify the air leak location. These results may help in the overall design of a monitoring and alarm system for the successful implementation and operation of CAES in LRCs. [ABSTRACT FROM AUTHOR]

The article discusses a study conducted to determine the width of the pillar between two rock caverns for thermal energy storage using a thermal-mechanical coupled model. It analyzed the concentration of the stress at the pillar side of the caverns and observed local failures at the sidewalls of caverns due to the stress concentration and thermal stresses.

A new velocity and balance control algorithm for the RWBR (Reaction wheel bicycle robot) has been proposed in this paper. A reaction wheel is adopted to maintain a balance while the RWBR is driving, which allows the process of controlling the speed to be achieved concurrently with the one of controlling the balance. To control the speed of the bicycle robot, a PID control algorithm with the adjustment of variable gains is developed in this study, where the gains are heuristically adjusted during each experiment. For the control of the balance and stability, a roll controller is designed by using the model-based algorithm to provide the shortest possible cycle for the bicycle controller. The roll angle is measured to maintain the desired acceleration which generates the reaction force to keep the total force acting on the bicycle robot inside the friction cone. The desired roll acceleration is decided for the bicycle robot in order to prevent it from falling down to the floor with the minimum usage of the reaction wheel rotation. For the general driving of the bicycle robot such as the S-curved driving, the dynamic forces of centrifugal, gravity and steering change are modeled and the friction on the floor has been estimated. The performance of the designed control system is verified through the real experiments with the developed RWBR. [ABSTRACT FROM AUTHOR]

Prunus padus bark extract was tested for use as a natural cosmetic ingredient. P. padus bark extract was obtained by hot water extraction and succeeding maturing processes. Total polyphenol and flavonoid concentrations were measured, and safety test (cell toxicity test), efficacy tests (antioxidation, antiwrinkle, whitening), and temperature stability tests were conducted in experiments. Total polyphenol and flavonoid concentrations were 714.7±0.5 mg/g and 72.1±2.2mg/g, respectively. Compared with other natural antioxidants, polyphenol concentration in P. padus bark extract was extremely high. P. padus bark extract showed lower cell toxicity in 100-500 μg/ml concentration by MTT assay. P. padus bark extract indicated 71% DPPH free radical scavenging activity (antioxidation), 36% elastase inhibition (antiwrinkle), and 38% tyrosinase inhibition (whitening) at 350 μg/ml, respectively. W/O/W lotion formulation containing 1% P. padus extract was prepared and stability tests were done to see variations in cosmetic properties. Viscosity, pH, particle size, and appearance of lotion containing 1% P. padus extract maintained stable condition for 28 days. Particle size of lotions showed homogeneous 362-426 nm ranges during stability tests. From this study, P. padus bark extract displayed strong possibility as a natural antioxidative cosmetic agent. [ABSTRACT FROM AUTHOR]

The operating performance, spring characteristics, and material properties of a gas-insulated circuit breaker were optimized using multibody dynamics. The circuit breaker consisted of several latches and a cam. The dynamic behavior of the latches was affected by the spring characteristics, as well as by the materials and length of each latch. Our results indicated that the motion of the latches was a key factor in determining the opening time of the circuit breaker. A multibody model for the circuit breaker was developed and verified by comparing simulated results with experimental data. The opening time for the breaker was reduced by 1.5 ms in simulations. [ABSTRACT FROM AUTHOR]

Highway construction investments have diverse effects, including direct effects on the users, such as the reduction of travel time, car operation, and traffic accident costs, and indirect effects such as balanced regional development, regional economic development, and employment creation. Of these effects, the direct-employment-creation effect of South Korea's expressway construction investments was analyzed in this study, with the use of actual data. To examine the effects of expressway construction investments, the expressways were reviewed by category. It was found that the expressway length and investments as well as the traffic volumes on the expressways steadily rose until 2008 and slightly declined thereafter. The traffic volume per travel distance was also reviewed, and it was found that 56% of the expressway users covered a distance of under 40 km, which suggests that they used other transport means to travel over longer distances. Regarding the traffic volume trends per line, the opening of the Korea Train Express (KTX) did not significantly affect the use of expressways. The expressway construction sections, population trends, wholesale and retail sales, and regional gross product trends were also analyzed, and the results of the analysis suggest that expressway construction contributed to balanced regional development. In this study, to determine the direct-employment-creation effects of expressway construction investments, multiple-regression analysis of data regarding 68 expressway sections was conducted. The creation of direct employment means the employment of manpower input directly to the works regarding the construction and maintenance of an expressway, so the employment can be determined clearly through the construction of an expressway. The results of the analysis indicated that the country's KRW 1 billion worth of expressway construction investments created 7.27 full-time jobs. [ABSTRACT FROM AUTHOR]

The KAERI Center for Quantum Beam-Based Radiation Research, was founded in 2011. The center pursues the development of advanced radiation sources and their applications in biology, material science, and nuclear physics. There are two main research topics in the development of advanced radiation sources: a system with high-power T-ray pump and an ultrashort X-ray probe system and a compact electron storage ring based on a laser-accelerated electron beam. [ABSTRACT FROM AUTHOR]

The halo effect is raters' undesirable tendency to assign more similar ratings across rating criteria than they should. The impacts of the halo effect on ratings have been studied in rater-mediated L2 writing assessment. Little is known, however, about the extent to which rating criteria order in analytic rating scales is associated with the magnitude of the group- and individual-level halo effects. Thus, this study attempts to examine the extent to which the magnitude of the halo effect is associated with rating criteria order in analytic rating scales. To select essays untainted by the effects of rating criteria order, a balanced Latin square design was implemented along with the employment of four expert raters. Next, 11 trained novice Korean raters rated the 30 screened essays with respect to the four rating criteria in three different rating orders: standard-, reverse-, and random-order. A three-facet rating scale model (L2 writer ability, rater severity, criterion difficulty) was fitted to estimate the group- and individual-level halo effects. The overall results of this study showed that the similar magnitude of the group-level halo effect was detected in the standard- and reverse-order rating rubrics while the random presentation of rating criteria decreased the group-level halo effect. A theoretical implication of the study is the necessity of considering rating criteria order as a source of construct-irrelevant easiness or difficulty when developing analytic rating scales. [ABSTRACT FROM AUTHOR]