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A theory of the time-resolved photoemission spectroscopy (TRPES) is developed, which enables to explore the real-time electron dynamics of infinitely periodic crystalline solids. In the strongly correlated electron systems NiO and CuO, the early-stage dynamics of the valence band edge are found to be sharply contrasted between those in the spectra of TRPES. This provides a new dynamical insight to the Zaanen–Sawatzky–Allen (ZSA) classification scheme of correlated insulators and makes us assert that NiO dynamically behaves like the Mott–Hubbard insulator (MHI) and CuO like the charge transfer insulator (CTI). In the two-dimensional carbon layer graphene, the real-time electron dynamics of quantum-phase-dressed excited states, i.e., due to the Berry phase and the pseudospin correlation, are investigated in an unprecedented way through the time-resolved angle-resolved photoemission spectroscopy (TR-ARPES). In particular, the dephasing dynamics of optically doped electrons and holes in the massless Dirac band, accompanying a field-induced gliding of the Dirac cone, are discovered.

For better life, medical and IT technology are converging and data plays a key role in this convergence. Data in the medical field is information about humans, and these data are sensitive. Because this type of data is frequently accessed by multiple users, a high degree of caution is required during handling. In addition, systematic security precautions must be followed to prevent data from being used outside of the intended purpose, even in clinical research. In this paper, we propose a human-centric framework for clinical environments based on the standards, procedures, and methods outlined in guidelines published in the United States and Korea. This study provides a more balanced approach to the utilization and security of personal information as compared to that in the two previously published guidelines. For the secure clinical studies, this framework makes it possible to provide utility and security in a balanced manner, depending on the forms of provision. As a result, the proposed framework extends the usability of the clinical study, and support secure usage of clinical research data.

Background Hesperidin is a flavonoid with antioxidant, anti-inflammatory, and immune modulatory activities. Photoaging is a consequence of chronic exposure to the sun and ultraviolet (UV) radiation. This study was designed to evaluate the efficacy of hesperidin against photoaging of dorsal skin in hairless mice. Methods Hairless male mice (6-week-old) were divided into three groups (n = 7): control, UVB-treated vehicle, and UVB-treated hesperidin groups. UVB-irradiated mice from hesperidin group were orally administered 0.1 mL of water containing 100 mg/kg body weight per day hesperidin. Results The mean length and depth of wrinkles in the UVB-treated hesperidin group significantly improved after the oral administration of hesperidin, which significantly inhibited the increase in epidermal thickness and epidermal hypertrophy (P < 0.05). UVB irradiation of mice induced epidermal barrier dysfunction including an increase in the transepidermal water loss (TEWL); however, hesperidin decreased the TEWL. UVB irradiation increased the expression of MMP-9 and pro-inflammatory cytokines whereas UVB-treated hesperidin group showed reduced expression. These results indicate that hesperidin showed anti-photoaging activity in the UVB-irradiated hairless mice. In conclusion, hesperidin inhibited the UVB-induced increase in skin thickness, wrinkle formation, and collagen fiber loss in male hairless mice. Conclusions These results suggest that hesperidin shows potent anti-photoaging activity by regulating MMP-9 expression through the suppression of MAPK-dependent signaling pathways.

The motion of address resolution protocol (ARP) is done without any problem in a general environment, but it is not considered from the security aspect; therefore, it risks being threatened by an attack from the network called ARP spoofing or ARP poisoning. The attacker can approach the transmission data between hosts by disguising itself as a different host through an ARP spoofing attack and can isolate the host as the target of an attack from the network. In this paper, we propose a routing trace-based network security system for preventing ARP spoofing attacks. Our proposed system includes detection, protection, and recovery techniques to prevent an ARP spoofing attack in the internal network. Whether an ARP spoofing attack occurs is confirmed through the periodic monitoring of the ARP table and a routing trace. The system can prevent ARP spoofing attacks without modifications to the ARP or the addition of cryptographic measures. In addition, it provides security and efficiency by overcoming the weak points of the existing researches.

A variety of research is in progress to detect wanted scenes from videos. A method of detecting scenes wanted by a user through scene rearrangement based on calculated visual similarity is limited in that such a method does not reflect elements along the storyline through which a user remembers a movie. A movie's story is built up by characters, and such build-up is closely related with emotions of characters in a film. A movie browsing system based on storyline is executable by applying characters and those characters' emotions. Thus, methods of extracting key characters in each scene and of clustering scenes through extraction of emotion vectors from dialogues in each scene are hereby suggested. This paper also proposes to develop a movie browsing method and a system based on emotions of characters.

The atomic-layered semiconducting materials of transition metal dichalcogenides are considered effective light sources with both potential applications in thin and flexible optoelectronics and novel functionalities. In spite of the great interest in optoelectronic properties of two-dimensional transition metal dichalcogenides, the excitonic properties still need to be addressed, specifically in terms of the interlayer interactions. Here, we report the distinct behavior of the A and B excitons in the presence of interlayer interactions of layered MoS2 crystals. Micro-photoluminescence spectroscopic studies reveal that on the interlayer interactions in double layer MoS2 crystals, the emission quantum yield of the A exciton is drastically changed, whereas that of the B exciton remains nearly constant for both single and double layer MoS2 crystals. First-principles density functional theory calculations confirm that a significant charge redistribution occurs in the double layer MoS2 due to the interlayer interactions producing a local electric field at the interfacial region. Analogous to the quantum-confined Stark effect, we suggest that the distinct behavior of the A and B excitons can be explained by a simplified band-bending model.

Human neuroblastoma is the most commonly diagnosed solid tumor in children. The existence and development of S-type cells is important for the prognosis and malignant properties in neuroblastoma patients. However, their origin is controversial and the relationship between S- and N-type cells in neuroblastoma has not yet been clarified. To investigate the feasibility of inter-conversion and characteristic features between S-type cells lacking malignant potential and N-type cells having metastatic potential, the genomic profiles of neuroblastoma SH-EP (S-type) and SH-SY5Y (N-type) cells were compared at high resolution. Common gain segments (>10 Mb) between SH-EP and SH-SY5Y cells were observed at 1q21.1–q44 and 17q21.32–q25.3. The results of the fluorescent in situ hybridization (FISH) analysis showed good agreement with the array-CGH data. Genome-wide inspection of SH-EP and SH-SY5Y cells successfully identified not only common chromosomal aberrations but also genomic variations, suggesting that interconversion could not take place between S- and Ntype cells. The identified differences between less aggressive S-type cells (SH-EP) and highly aggressive neuroblastic N-type cells (SH-SY5Y) might be useful for understanding tumorigenicity and discovery of potential new markers in neuroblastoma. This is the first effort to compare genomic profiles between less aggressive S-type cells (SH-EP) and highly aggressive neuroblastic N-type cells (SH-SY5Y) at high resolution.

The stacking order in layered transition-metal dichalcogenides (TMDCs) induces variations in the electronic and interlayer couplings. Therefore, controlling the stacking orientations when synthesizing TMDCs is desirable but remains a significant challenge. Here, we developed and showed the growth kinetics of different shapes and stacking orders in as-grown multi-stacked MoS2 crystals and revealed the stacking-order-induced interlayer separations, spin–orbit couplings (SOCs), and symmetry variations. Raman spectra in AA(A…)-stacked crystals demonstrated blueshifted out-of-plane (A1g) and in-plane (E2g1) phonon frequencies, representing a greater reduction of the van der Waals gap compared to conventional AB(A…)-stacking. Our observations, together with first-principles calculations, revealed distinct excitonic phenomena due to various stacking orientations. As a result, the photoluminescence emission was improved in the AA(A…)-stacking configuration. Additionally, calculations showed that the valence-band maxima (VBM) at the K point of the AA(A…)-stacking configuration was separated into multiple sub-bands, indicating the presence of stronger SOC. We demonstrated that AA(A…)-stacking emitted an intense second-harmonic signal (SHG) as a fingerprint of the more augmented non-centrosymmetric stacking and enabled SOC-induced splitting at the VBM. We further highlighted the superiority of four-wave mixing-correlated SHG microscopy to quickly resolve the symmetries and multi-domain crystalline phases of differently shaped crystals. Our study based on crystals with different shapes and multiple stacking configurations provides a new avenue for development of future optoelectronic devices. A method for investigating the relative alignment of stacks of two-dimensional layers has been developed by researchers in Korea. Two-dimensional materials, those just a single atom thick, have a host of unusual electronic and optical properties. Placing two-dimensional materials on top of each other to create thicker films offers a way to engineer further novel materials, but the properties of these stacks depend crucially on the relative orientation of each layer. Jong-Hyun Ahn from Yonsei University and colleagues synthesized stacks of molybdenum disulfide monolayers with various angular alignments using a technique called atmospheric-pressure chemical vapor deposition. They then characterized the structures optically and measured a gradual spectroscopic evolution induced by the varying the arrangement. This insight will be useful for designing future optoelectronic devices based on molybdenum disulfide monolayers. NaCl-assisted APCVD technique to synthesize multi-stacked MoS2 crystals with different stacking orientations and shape has been developed. We found that the stacking orientation of multi-stacked MoS2 crystals shows the underlying variation in the crystalline phases, symmetry inversion, spin–orbit coupling and interlayer interactions through intensive optical study based on Raman spectroscopy, PL spectroscopy and nonlinear technique of FWM correlated SHG imaging technique. Our study based on the crystals with different shape and multiple stacking configurations provide a new avenue for the possibilities of future optoelectronic devices.

The objective of this study was to determine the anticancer effects of the Pacific oyster (Crassostrea gigas) in vitro. For this study, the lipid extracts of C. gigas were prepared using several organic solvents: methanol, chloroform, hexane, methanol:chloroform=1:1, chloroform: hexane=1:1. The anticancer activity of the extracts was evaluated using cell cycle and apoptosis assays analyzed by a flow cytometry. Of all the extracts, the hexane extracts exhibited the highest anticancer activity compared to the other extracts. The hexane extracts were further separated and purified using thin layer chromatography. The final isolated lipid compounds were identified their components as palmitic acid, margaric acid, and stearic acid. These results indicate that this combination of lipids effectively inhibit in vitro human prostate tumor growth by inducing apoptosis of cancer cells.

Pro-inflammatory mediators, such as prostaglandin E2 (PGE2) and nitric oxide (NO), and pro-inflammatory cytokines such as interleukin (IL)-1beta, IL-6, and TNF-alpha, play pivotal roles in brain injuries. The anti-inflammatory properties are known to be associated with significant reductions in pro-inflammatory mediators in brain injuries. In the present study we investigate whether the effects of curcumin on the production of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated BV2 microglia.Curcumin were administered and their effects on LPS-induced pro-inflammatory mediators were monitored by Western blotting and RT-PCR.Curcumin significantly inhibited the release of NO, PGE2, and pro-inflammatory cytokines in a dose-dependent manner. Curcumin also attenuated the expressions of inducible NO synthase and cyclooxygenase-2 mRNA and protein levels. Moreover, curcumin suppressed NF-kappaB activation via the translocation of p65 into the nucleus. Our data also indicate that curcumin exerts anti-inflammatory properties by suppressing the transcription of proinflammatory cytokine genes through the NF-kappaB signaling pathway.Anti-inflammatory properties of curcumin may be useful for treating the inflammatory and deleterious effects of microglial activation in response to LPS stimulation.

Some deep drawing characteristics at elevated temperatures were investigated for the SCP1 steel sheets by using a Cr-coated die. For this investigation, six different temperatures between room temperature and 250°C, and six different drawing ratios ranging from 2.4 to 2.9 were considered. As a result, the limiting drawing ratio, the maximum drawing force and the maximum drawing depth were found to be affected sensitively by temperature, and more stable through-thickness strain distribution was observed at elevated temperatures. Some experimental results compared favorably with theoretical, results obtaine by using the finite element method.

Glycosides were synthesized from soluble starch and hydroxybenzylalcohols (o, m and p) by the transglycosylation activity of amyloglucosidase from Rhizopus sp. in a water system. The synthesized glycosides were identified as hydroxybenzyl-α-glucosides, of which one molecule of hydroxybenzylalcohol was bound to 1-OH of glucose. The transglycosylation reaction was performed in a reaction system containing 50 mg starch, 50 mg hydroxybenzylalcohol, and 10 units of enzyme in pH 5.0 at 45 °C. The glycoside was rapidly hydrolyzed to glucose and hydroxybenzylalcohol by the α-glucosidase.

In this study, silica-based organic–inorganic hybrid coating materials were prepared by the sol–gel method. Tertaethoxysilane and polyvinyl alcohol were used as the inorganic and organic compounds, respectively. The substrate polypropylene film surface was modified by corona-plasma treatment to provide appropriate adhesion between the coating material and the polymer base film. A silane.coupling agent of vinyltriethoxysilane was also used to improve the adhesion between the base film and the coated layer. The effects of vinyltriethoxysilane in the hybrid materials were investigated using Fourier transform infrared analyses and X-ray diffraction. The vinyl group of vinyltriethoxysilane increased the hydrophobicity of the hybrid materials. The polypropylene films coated with the hybrid materials were characterized by examining their morphology, optical transparency and oxygen permeability. The results showed that the formation of hydrogen bonds between polyvinyl alcohol and the other compounds affected the microstructure of the coating solution and the final oxygen permeation property. Further, although the presence ofvinyltriethoxysilane in the hybrid coating solution could improve adhesion between the coated layer and the polymer base film, it deteriorates the effectiveness of the barrier to prevent of oxygen permeation through the coated film. However, the coated film maintained visible transparency and even enhanced the transmission of long wavelength visible-light owing to refractive index matching.

The JNK inhibitor SP600125 strongly inhibits cell proliferation in many human cancer cells by blocking cell-cycle progression and inducing apoptosis. Despite extensive study, the mechanism by which SP600125 inhibits mitosis-related effects in human leukemia cells remains unclear. We investigated the effects of SP600125 on the inhibition of cell proliferation and the cell cycle, and on microtubule dynamics in vivo and in vitro. Treatment of synchronized leukemia cells with varying concentrations of SP600125 results in significant G2/M cell cycle arrest with elevated p21 levels, phosphorylation of histone H3 within 24 h, and endoreduplication with elevated Cdk2 protein levels after 48 h. SP600125 also induces significant abnormal microtubule dynamics in vivo. High concentrations of SP600125 (200 microM) were required to disorganize microtubule polymerization in vitro. Additionally, SP600125- induced delayed apoptosis and cell death was accompanied by significant poly ADP-ribose polymerase (PARP) cleavage and caspase-3 activity in the late phase (at 72 h). Endoreduplication showed a greater increase in ectopic Bcl-2-expressing U937 cells at 72 h than in wild-type U937 cells without delayed apoptosis. These results indicate that Bcl-2 suppresses apoptosis and SP600125-induced G2/M arrest and endoreduplication. Therefore, we suggest that SP600125 induces mitotic arrest by inducing abnormal spindle microtubule dynamics.