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A building-integrated bifacial photovoltaic (BF-PV) module is a strong candidate for realizing zero-energy buildings because it can achieve high power output by collecting light from both the front and rear sides of the building. However, harvesting non-uniformly distributed rear incident light is a very challenge issue in BF-PV. In this study, we empirically investigated the effect of an inhomogeneous rear surface on the power and reliability of a BF-PV. The mini-module test showed that a non-uniform rear reflection triggers a current mismatch among cells, resulting in the overheating of cells above the low reflectance surface. In particular, a large difference in the reflectance inside the rear reflector installed close to the module increases a hot-spot risk. This risk can be reduced by minimizing the variation of the reflectance, as well as elongating the distance between the cell and the reflector. A theoretical calculation based on empirical results indicated that an inhomogeneous rear reflector results in power loss or a reliability issue in BF-PV modules. Hence, the rear surface of a BF-PV module should be carefully designed or considered in order to maximize its performance and reliability.

Nuclear power generates a large portion of the energy used today and plays an important role in energy development. To ensure safe nuclear power generation, it is essential to conduct an accurate analysis of reactor structural integrity. Accordingly, in this study, a methodology for obtaining accurate structural responses to the combined seismic and reactor coolant loads existing prior to the shutdown of a nuclear reactor is proposed. By applying the proposed analysis method to the reactor vessel internals, it is possible to derive the seismic responses considering the influence of the hydraulic loads present during operation for the first time. The validity of the proposed methodology is confirmed in this research by using the finite element method to conduct seismic and hydraulic load analyses of the advanced APR1400 1400 MWe power reactor, one of the commercial reactors. The structural responses to the combined applied loads are obtained using displacement-based and stress-based superposition methods. The safety of the subject nuclear reactor is then confirmed by analyzing the design margin according to the American Society for Mechanical Engineers (ASME) evaluation criteria, demonstrating the promise of the proposed analysis method. Keywords: Nuclear reactor internals, Seismic analysis, Finite element analysis, Pump-pulsation, Turbulence, Displacement-based stress assessment

Plasma-assisted atomic layer deposition (PA-ALD) is more suitable than thermal atomic layer deposition (ALD) for mass production because of its faster growth rate. However, controlling surface damage caused by plasma during the PA-ALD process is a key issue. In this study, the passivation characteristics of Al2O3 layers deposited by PA-ALD were investigated with various O2 plasma exposure times. The growth per cycle (GPC) during Al2O3 deposition was saturated at approximately 1.4 A/cycle after an O2 plasma exposure time of 1.5 s, and a refractive index of Al2O3 in the range of 1.65–1.67 was obtained. As the O2 plasma exposure time increased in the Al2O3 deposition process, the passivation properties tended to deteriorate, and as the radio frequency (RF) power increased, the passivation uniformity and the thermal stability of the Al2O3 layer deteriorated. To study the Al2O3/Si interface characteristics, the capacitance-voltage (C-V) and the conductance-voltage (G-V) were measured using a mercury probe, and the fixed charge density (Qf) and the interface trap density (Dit) were then extracted. The Qf of the Al2O3 layer deposited on a Si wafer by PA-ALD was almost unaffected, but the Dit increased with O2 plasma exposure time. In conclusion, as the O2 plasma exposure time increased during Al2O3 layer deposition by PA-ALD, the Al2O3/Si interface characteristics deteriorated because of plasma surface damage.

This study was conducted to isolate and identify the anti-inflammatory active peptide in black soybean treated by high hydrostatic pressure after germination. The anti-inflammatory activity was examined using RAW 264.7 macrophages. Black soybean was germinated for 4 days and subjected to 150 MPa for 24 h, followed by preparation of protein extracts. The extracts were sequentially filtered using membranes with a molecular weight cutoff of 30, 10, and 3 kDa. A strong inhibitory effect was observed with the 3–10 kDa fraction. The active peptide from this fraction was purified by gel permeation column chromatography and first and second semi-preparative HPLC. After isolation and purification of the active peptide, secretion of inflammatory markers (nitric oxide, TNF-α, IL-1β, and IL-6) by LPS-stimulated RAW 264.7 macrophages was measured. The purified anti-inflammatory peptide was analyzed by UV, LC–MS, 1H and 13C NMR, COSY, HMBC, and HSQC and was identified as a tripeptide.

The Global Positioning System (GPS) has become an effective tool for estimating ionospheric total electron content (TEC). One of the critical factors affecting ionospheric TEC estimation from GPS data is the differential code biases (DCBs) inherent in both GPS receivers and satellites. To investigate the factor that affects the receiver DCB, we consider the relationship between the receiver DCB and the grounding of an antenna. GPS data from 9 stations in South Korea from three periods (the years 2009, 2014, and 2017) were used in the analysis. It was found that a significant jump (∼8–13 ns, or ∼ 23–37 TECU) in hourly DCB time series occurred simultaneously at the two different sites when an antenna is changed from a grounded to the non-grounded state. Thus, our study clearly identifies that the grounding of GPS equipment is a factor of the receiver DCB changes.

In this study, the effects of sucrose on nutritional and functional composition as well as antioxidant activities in buckwheat sprouts during germination were investigated. Treatment with 1%, 2%, or 3% sucrose resulted in an increase in the amount of vitamins, four C-glycosylflavones, and rutin. Tocopherols and β-carotene in sprouts treated with 1%, 2%, and 3% sucrose were increased in a dose-dependent manner. Similarly, the sum of individual flavonoid was 1.35, 1.29, and 1.60 times higher than that of control sprouts. Sucrose treatment increased tyrosine and phenylalanine ammonia-lyase activities resulting in an increase in the flavonoid content. Moreover, treatment of HepG2 cells with buckwheat sprouts ameliorated oxidative damages by modulating reactive oxygen species production, malondialdehyde generation, and antioxidant enzyme activities. These results suggest that sucrose treatment could improve the nutritional composition and antioxidant effects of germinating buckwheat sprouts.

Few studies have assessed the probiotic characteristics and antioxidant activity of the kefir-derived yeast, Kluyveromyces marxianus, and its synergistic interactions with polyphenol-rich grape seed flour (GSF)/extract (GSE). We examined several probiotic characteristics (gastric resistance, intestinal resistance, cholesterol reduction, adhesiveness to intestinal cells) of four K. marxianus strains. Each of the yeasts showed 5–25% greater intestinal cell adhesiveness than that of Lactobacillus acidophilus. Among the four yeast strains, K. marxianus KU140723-02 (KM2) exhibited the greatest antioxidant activity. When incubated with GSF/GSE, its antioxidant activity was synergistically increased by two-fold. In conclusion, a combination of kefir-derived yeast KM2 and GSF/GSEs may be a novel functional food ingredient with antioxidant properties targeting gut health.

The objective of this study was to investigate the protective effect of esculetin against ethanol-induced liver injury in both HepG2 cells and mice. Treatment with esculetin significantly prevented ethanol-induced cytotoxicity in HepG2 cells by reducing the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). This protective effect was likely associated with antioxidant potential of esculetin, as evidenced by the attenuation of reactive oxygen species (ROS) and malondialdehyde (MDA) production and restoration of the depleted glutathione (GSH) levels in ethanol-induced HepG2 cells. Esculetin also dramatically increased the nuclear translocation of NF-E2-related factor 2 (Nrf2) and antioxidant response element (ARE) reporter gene activity, which led to the upregulation of ARE-responsive enzymes. In animal studies, esculetin markedly prevented ethanol-induced liver injury by reducing GSH depletion, MDA production, and the lipid contents in liver. Moreover, esculetin lowered the levels of serum ALT, serum AST, and the content of serum lipids.

Summary Although medial prefrontal cortex (mPFC) is known to play important roles in social behaviors, how early social experiences affect the mPFC and its subcortical circuit remains unclear. We report that mice singly housed (SH) for 8 weeks after weaning show a social recognition deficit, even after 4 weeks of resocialization. In SH mice, prefrontal infralimbic (IL) neurons projecting to the shell region of nucleus accumbens (NAcSh) show decreased excitability compared with group-housed (GH) mice. NAcSh-projecting IL neurons are activated when GH mice encounter a familiar conspecific, which is not observed in SH mice. Chemogenetic inhibition of NAcSh-projecting IL neurons in normal mice impairs social recognition without affecting social preference, whereas activation of these neurons reverses social recognition deficit in SH mice. Our findings demonstrate that early social experience critically affects mPFC IL-NAcSh projection, the activation of which is required for social recognition by encoding information for social familiarity.

Prostate cancer is the second most common cancer in males. The side effects of convention antineoplastic drugs and sustained risks of recurrence and metastasis necessitate the search for safer chemopreventive and chemotherapeutic drugs. The cereal grain sorghum contains various polyphenols with potent anti-cancer and antioxidant activities. To evaluate the anti-tumor efficacy of Donganme sorghum ethyl-acetate extract (DSEE), we performed content analysis and evaluated its effects on PC3M prostate cancer cell proliferation, cell cycle progression, and migration in vitro, and on PC3M orthotopic tumor growth in vivo. DSEE decreased viable cell number in a dose-dependent manner, increased apoptosis rate by activating the intrinsic apoptosis pathway, induced cell cycle arrest at G0 by reducing cyclin expression, suppressed cell migration and expression of matrix metalloproteinase-2 and -9. Moreover, DSEE inhibited orthotopic tumor growth and metastasis in mice. Therefore, DSEE may have potential preventive and therapeutic efficacy against prostate cancer.

We investigated the influence of high hydrostatic pressure (HHP) and pre-germination on black soybean protein and peptide characteristics. Black soybean was germinated (2 or 4 d) and subjected to HHP (0.1–150 MPa; 24 h), followed by preparation of extracts and testing for anti-inflammatory activity. The highest soluble protein content (815.85 mg/g) was in soybeans subjected to HHP (100 MPa) after germination (4 d). Germination and HHP caused the degradation of high molecular weight proteins; we detected the highest content of

Smartphone cameras are increasingly used for document capture in daily life. To understand user behaviors, we performed two studies: (1) an online survey (n=106) to understand general smartphone camera usage behaviors related to information capture, as well as participants' experiences of orientation errors, and (2) a controlled lab study (n=16) to understand detailed document capture behaviors and to identify patterns in orientation errors. According to our online survey, 79.30% of the respondents reported experiencing orientation errors during document capture. In addition, our lab study showed that more than 90% of landscape capture tasks result in incorrect orientation. To solve this problem, we systematically analyzed the user behavior during document capture (e.g., video sequences and photographs taken or hand grip used) and propose a novel solution called ScanShot, which detects document capture time to help users correct orientation errors. ScanShot tracks the direction of gravity during document capture and monitors the users rotational or tilting movements of to update changes in orientation automatically. Our results confirm that document capture with 93.44% accuracy; in addition, our orientation update mechanism can reduce orientation errors by 92.85% using a gyroscope (for rotation) and 81.60% using an accelerometer (for micro-tilts). HighlightsWe study user behavior of document capturing using mobile camera by online study (n=106) and in-lab experiment (n=16).We analyze the erroneous orientation problem during document photo capturing.We propose a technique devised for inferring the user's document capture intention.We device two methods for correcting orientation errors while document capturing.The proposed methods show that more than 80% of error are be corrected.

Structural integrity is the first priority in the design of nuclear reactor internal structures. In particular, nuclear reactor internals should be designed to endure external forces, such as those due to earthquakes. Many researchers have performed finite element analyses to meet these design requirements. Generally, a seismic analysis model should reflect the dynamic characteristics of the target system. However, seismic analysis based on the finite element method requires long computation times as well as huge storage space. In this research, a beam element model was developed and confirmed based on the real dynamic characteristics of an advanced pressurized water nuclear reactor 1400 (APR1400) system. That verification process enhances the accuracy of the finite element analysis using the beam elements, remarkably. Also, the beam element model reduces seismic analysis costs. Therefore, the beam element model was used to perform the seismic analysis. Then, the safety of the APR1400 was assessed based on a seismic analysis of the time history responses of its structures. Thus, efficient, accurate seismic analysis was demonstrated using the proposed beam element model.

This study investigated the effects of a silk peptide fraction obtained by incubating silk proteins with Protease N and Neutrase (SP-NN) on cognitive dysfunction of Alzheimer disease model rats. In order to elucidate underlying mechanisms, the effect of SP-NN on the expression of choline acetyltransferase (ChAT) mRNA was assessed in F3.ChAT neural stem cells and Neuro2a neuroblastoma cells; active amino acid sequence was identified using HPLC-MS. The expression of ChAT mRNA in F3.ChAT cells increased by 3.79-fold of the control level by treatment with SP-NN fraction. The active peptide in SP-NN was identified as tyrosine-glycine with 238.1 of molecular weight. Male rats were orally administered with SP-NN (50 or 300mg/kg) and challenged with a cholinotoxin AF64A. As a result of brain injury and decreased brain acetylcholine level, AF64A induced astrocytic activation, resulting in impairment of learning and memory function. Treatment with SP-NN exerted recovering activities on acetylcholine depletion and brain injury, as well as cognitive deficit induced by AF64A. The results indicate that, in addition to a neuroprotective activity, the SP-NN preparation restores cognitive function of Alzheimer disease model rats by increasing the release of acetylcholine.

In this study, the characterizations and adsorption efficiencies for chromium, copper and nickel were evaluated using manufacture-grade Fe2O3-carbon foam. SEM, XRD, XRF and BET analyses were performed to determine the characteristics of the material. Various pore sizes (12–420 μm) and iron contents (3.62%) were found on the surface of the Fe2O3-carbon foam. Fe2O3-carbon foam was found to have excellent adsorption efficiency compared to carbon foam for mixed solutions of cationic and anionic heavy metals. The adsorption capacities for chromium, copper and nickel were 6.7, 3.8 and 6.4 mg/g, respectively, which were obtained using a dual exponential adsorption model. In experiments with varying dosages of the Fe2O3 powder, no notable differences were observed in the removal efficiency. In a fixed-bed column test, Fe2O3-carbon foam achieved adsorption capacities for chromium, copper and nickel of 33.0, 12.0 and 9.5 mg/g, respectively, after 104 h. Based on these results, Fe2O3-carbon foam was observed to be a promising material for treatment of plating wastewater.

Summary Pain sensation is powerfully modulated by signal processing in the brain, and pain becomes chronic with the dysfunction of the pain modulatory system; however, the underlying mechanisms are unclear. We found that the metabotropic glutamate receptor 5 (mGluR5) in the periaqueductal gray (PAG), the key area of endogenous pain modulation, is persistently active in normal conditions to maintain an appropriate sensory perception. In the neuropathic pain condition, Homer1a, an activity-dependent immediate early gene product, disrupted the persistent mGluR5 activity resulting in chronic pain. Remarkably a single-time blockage of the mGluR5 resulted in chronic neuropathic pain-like symptoms even in the absence of nerve injury. The decline of mGluR5 activity induced the pain modulatory dysfunction with a profound reduction of excitability of PAG neurons. These findings uncover the role of the persistent mGluR5 activity in vivo and provide new insight into how pain becomes chronic with the maladaptive coping of the PAG to pain sensation.

This study investigated the changes in content, purity, physical properties, and in vitro binding properties of barley β-glucan by oxidation treatment. Barleys (Hordeum vulgare) were oxidized, using different concentrations of hydrogen peroxide (0.2-1.0% H2O2). The total and soluble β-glucan contents ranged from 8.41% and 4.81% in the control to 9.48% and 6.45% in the 0.6% H2O2 treatment. With increasing H2O2 concentration, the purity of β-glucan increased from 35% to 70%, whereas molecular weight (MW), viscosity, and water-binding capacities decreased to 2.0 × 10(4)Da, 3.9 cP, and 4.45 g water/g β-glucan, respectively. Oil binding capacities ranged from 8.29 g of oil/g in non-oxidized β-glucan to 9.42 g of oil/g in β-glucan oxidized with 0.6% H2O2. The MW, viscosity, and binding capacities of waxy barley β-glucan were higher than those of non-waxy barley β-glucan. Oxidation by hydrogen peroxide improved the physical properties and in vitro binding capacity of barley β-glucan.

We prepared a bone plate enabled with the local, sustained release of alendronate, which is a drug known to inhibit osteoclast-mediated bone resorption and also expedite the bone-remodeling activity of osteoblasts. For this, we coated a bone plate already in clinical use (PLT-1031, Inion, Finland) with a blend of alendronate and a biocompatible polymer, azidobenzoic acid-modified chitosan (i.e., Az-CH) photo-crosslinked by UV irradiation. As we performed the in vitro drug release study, the drug was released from the coating at an average rate of 4.03μg/day for 63days in a sustained manner. To examine the effect on bone regeneration, the plate was fixed on an 8mm cranial critical size defect in living rats and the newly formed bone volume was quantitatively evaluated by micro-computed tomography (micro-CT) at scheduled times over 8weeks. At week 8, the group implanted with the plate enabled with sustained delivery of alendronate showed a significantly higher volume of newly formed bone (52.78±6.84%) than the groups implanted with the plates without drug (23.6±3.81%) (p

For screen-printed silicon solar cells, optimization of the contact characteristics between the front metal electrode and silicon is very significant for realizing high efficiency. As technology advances, the solar cell efficiency has been steadily increased. Especially, as surface recombination becomes more important in high efficiency solar cells, understanding and controlling recombination in the metal contact area are necessary. Recombination at the metal-silicon interface is a major cause of the drop in the open-circuit voltage (Voc) of a solar cell. Thus far, the study of electrodes in silicon solar cells has been largely aimed at reducing the series resistance, and few studies on recombination due to electrodes have been performed. Quantitatively evaluating the recombination in electrodes to assess the effect on the efficiency is expected to become more important in the near future. In this paper, the contact characteristics of a screen-printed silver electrode and silicon interface were analyzed using saturation current density (Jo) measurements according to the surface doping concentration and firing temperature. The effects of the contact characteristics on Voc and recombination were also investigated. Experimental results showed that Jo.pass decreased with decreasing surface doping concentration and Jo.metal increased with increasing surface doping concentration and firing temperature. For quantitative analysis of Jo.metal, the size and distribution of Ag crystallites were observed using SEM and TEM, and the Ag concentration was analyzed by ICP-OES measurements. The larger Jo.metal was, the higher the Ag crystallite concentration, indicating that the Ag crystallites under the electrode increased Jo.metal. The effect of Jo.metal on the electrical characteristics of the solar cell was analyzed by calculating the change in the surface recombination velocity and the decreased width of Voc. Through this study, the recombination in the metallized area, which is expected to become increasingly important, and particularly the effects of the doping profile of the emitter region and silver crystallites on the surface recombination were quantitatively assessed. The amount of silver crystallites on the silicon wafer was quantitatively analyzed.

Stroke is one of the most-devastating brain diseases causing acute death or permanent disability. Although tissue-type plasminogen activator was approved by Food and Drug Administration for early reperfusion of the occluded vessels, oxidative injury may cause extensive brain infarction. Accordingly, there is a need for effective neuroprotection during reperfusion, and stem cell-based therapeutic approaches should fulfill this requirement. We established human neural stem cells (NSCs) encoding gene of choline acetyltransferase (F3.ChAT), an acetylcholine-synthesizing enzyme, and investigated whether infusion of the F3.ChAT cells attenuate the ischemia-reperfusion brain damage in a rat model of middle cerebral artery occlusion (MCAO). F3.ChAT cells were found to produce much higher amounts of ChAT as well as neuroprotective and anti-inflammatory neurotrophins than their parental F3 NSCs. After 2-h occlusion, the artery was reperfused, along with intravenous infusion of the stem cells (1 × 106 cells/rat). Administration of the F3.ChAT cells markedly reduced the infarction volume and improved both the cognitive dysfunction and behavioural deficits of MCAO animals, in which F3.ChAT cells were superior to F3 cells. F3.ChAT cells not only restored microtubule-associated protein-2, a neuronal cytoskeletal protein, and preserved microvessels, but also suppressed lipid peroxidation, pro-inflammatory cytokines, glial fibrillary acidic protein, and intercellular adhesion molecule-1 in the brain tissues. The results demonstrate that early intravenous infusion of NSCs expressing ChAT and neurotrophins attenuate brain and capillary injuries and restore neurobehavioural functions via neuroprotective and anti-inflammatory activities, and that F3.ChAT cells could be a candidate for the neuroprotection and functional recovery of acute stroke patients.