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Electrochemical sodiation is performed in crystalline Sn foil using in situ scanning electron microscopy (SEM) to simultaneously measure the changes in the electrical resistivity and volume of the Sn anode in a Na-Sn battery. We observe that sodiation causes an increase in the Sn anode resistivity by six orders of magnitude. Ab initio molecular dynamics simulations of the Na-Sn alloy system demonstrate that the increased resistivity of the anode is caused by the formation of an electrically resistive amorphous NaSn phase (a-NaSn) with a pseudogap. It is also observed that the formation of a-NaSn is always accompanied by a large volume expansion of ∼200%, causing the development of residual tensile stress. The residual stress in turn alters the electronic structure of the a-NaSn phase, further increasing the resistivity of a-NaSn and thus decreasing the energy efficiency of the Na-Sn battery.

A stereoselective synthesis of entecavir, an anti-hepatitis B (HBV) drug, was accomplished by a regioselective isopropylidene cleavage, stereoselective Sharpless epoxidation, and TiIII-mediated regio- and stereoselective epoxide cleavage as key steps.

Despite their large theoretical storage capability, Na–Sn batteries exhibit poor round-trip energy efficiencies as compared to Li–Si batteries. Here, we report the results of a comprehensive study to elucidate how and why Na–Sn batteries exhibit such a low energy efficiency. As a convincing evidence for this behavior, we observed that the resistivity of the Sn anode increased by 8 orders of magnitude during in situ sodiation experiments, which is attributed to the formation of electrically resistive Zintl ions in the sodiated Sn. Continual sodiation induced the development of residual stresses at the Sn anode and caused the distortion of Zintl ions from their ideal configuration. This distortion caused a change in the electronic structure, resulting in the increased resistivity of the sodiated Sn. Our findings offer some solutions that can be used to improve the energy efficiency of Na–Sn batteries.

Chemoresistive gas sensors based on two-dimensional (2D) materials including graphene-based materials have attracted significant research interest owing to their potential use in next-generation technologies including the Internet of Things (IoT). The functionalization of 2D materials is considered as a key strategy to achieve superior gas sensing properties such as high selectivity, high sensitivity, and reversible response and recovery, because it can modulate the chemical and electrical properties of 2D materials for more efficient gas sensing. Herein, we present a facile solution process and the room temperature gas sensing properties of chemically fluorinated graphene oxide (CFGO). The CFGO sensors exhibit improved sensitivity, selectivity, and reversibility upon exposure to NH3 with a significantly low theoretical detection limit of ∼6 ppb at room temperature in comparison to NO2 sensing properties. The effect of fluorine doping on the sensing mechanism is examined by first-principles calculations based on density functional theory. The calculations reveal that the fluorine dopant changes the charge distribution on the oxygen containing functional groups in graphene oxide, resulting in the preferred selective adsorption and desorption of NH3 molecules. We believe that the remarkable NH3 sensing properties of CFGO and investigation by first-principles calculations would enlarge the possibility of functionalized 2D materials for practical gas sensing applications such as the IoT.

Remote epitaxy enables to fabricate flexible GaN micro-LED sticker releasable from wafer., There have been rapidly increasing demands for flexible lighting apparatus, and micrometer-scale light-emitting diodes (LEDs) are regarded as one of the promising lighting sources for deformable device applications. Herein, we demonstrate a method of creating a deformable LED, based on remote heteroepitaxy of GaN microrod (MR) p-n junction arrays on c-Al2O3 wafer across graphene. The use of graphene allows the transfer of MR LED arrays onto a copper plate, and spatially separate MR arrays offer ideal device geometry suitable for deformable LED in various shapes without serious device performance degradation. Moreover, remote heteroepitaxy also allows the wafer to be reused, allowing reproducible production of MR LEDs using a single substrate without noticeable device degradation. The remote heteroepitaxial relation is determined by high-resolution scanning transmission electron microscopy, and the density functional theory simulations clarify how the remote heteroepitaxy is made possible through graphene.

When intracellular reactive oxygen species (ROS) increase, cancer cells are more vulnerable to oxidative stress compared to normal cells; thus, the collapse of redox homeostasis can lead to selective death of cancer cells. Indeed, recent studies have shown that inhibition of sulfiredoxin (Srx), which participates in antioxidant mechanisms, induces ROS-mediated cancer cell death. In this paper, we describe how an Srx inhibitor, J14 (4-[[[4-[4-(2-chlor-ophenyl)-1-piperazinyl]-6-phenyl-2-pyrimidinyl]thio]methyl]-benzoic acid), interferes with the antioxidant activity of Srx at the molecular level. We searched for possible binding sites of Srx using a binding site prediction method and uncovered two possible inhibition mechanisms of Srx by J14. Using molecular dynamics simulations and binding free energy calculations, we confirmed that J14 binds to the ATP binding site; therefore, J14 acts as a competitive inhibitor of ATP, settling the question of the two mechanisms. Based on the inhibition mechanism revealed at the atomic level, we designed several derivatives of J14, which led to LMT-328 (4-(((4-(4-(2-Chlorophenyl)piperazin-1-yl)-6-(2,4-dihydroxy-5-isopropylphenyl)pyrimidin-2-yl)thio)methyl)benzoic acid), which is possibly an even more potent inhibitor than J14.

2-Bromo-6-hydroxybenzofurans are potentially versatile intermediates for the divergent synthesis of numerous benzofuran-based natural products and their analogues. Herein we report the first one-pot strategy for the efficient synthesis of 2-bromo-6-hydroxybenzofurans. The present protocol provides shorter routes for the synthesis of moracins M, N, O and P; gramniphenols F and G; and morunigrol C using a protecting group-free approach.

Graphene is one of the most promising materials for high-performance gas sensors due to its unique properties such as high sensitivity at room temperature, transparency, and flexibility. However, the low selectivity and irreversible behavior of graphene-based gas sensors are major problems. Here, we present unprecedented room temperature hydrogen detection by Au nanoclusters supported on self-activated graphene. Compared to pristine graphene sensors, the Au-decorated graphene sensors exhibit highly improved gas-sensing properties upon exposure to various gases. In particular, an unexpected substantial enhancement in H2 detection is found, which has never been reported for Au decoration on any type of chemoresistive material. Density functional theory calculations reveal that Au nanoclusters on graphene contribute to the adsorption of H atoms, whereas the surfaces of Au and graphene do not bind with H atoms individually. The discovery of such a new functionality in the existing material platform holds the key to diverse research areas based on metal nanocluster/graphene heterostructures.

High-rate performance and mechanical stability of anode materials are the two important characteristics that are necessary to develop fast-charging batteries with longevity. In the present study, we demonstrate that both high rate performance and mechanical stability of the anode can be achieved with the Na-Sn battery system. Experiments show that the sodiation rate in crystalline Sn (c-Sn) is 2-3 orders of magnitude faster than that reported for the Li-Si system. Furthermore, this extraordinary rate is nearly the same regardless of the orientation of c-Sn, which can improve the cycle life by retarding the pulverization of c-Sn. Two main microstructural features responsible for the observed characteristics are identified: (1) a transformation from crystalline to amorphous phase occurring at thin layers of c-Sn near the interfacial front and (2) pipe diffusion of Na through sodiation-induced dislocations. In this study, the observed behaviors are explained by elucidating the diffusion kinetics, whereas the associated mechanistic origins are analyzed by resolving the diffusion process of Na+ near the Na/Sn interface using atomic simulations.

Alloying anodes have long attracted attention as promising candidate electrodes for application in grid‐level energy storage systems owing to their high energy capacity. Alloying anode‐based batteries, however, remain far from practical applications, which require several issues affecting cell performance to be addressed. The large volumetric expansion of anodes and associated phenomena that occur during battery cycling are the main reasons for the poor electrochemical performance of alloying anodes. These electrochemical behaviors of alloying anodes originate from the reactions between the unreacted anode material and inflowing carrier ions. Thus, the diffusion kinetics play a key role in determining the electrochemical properties of alloying anodes. Recent advances in analytical instruments and atomic simulations offer new approaches for interpreting anode performance. Beginning with a brief historical background, this review presents an overview of the origin of diffusion kinetics and how this concept has been extended to alloying anodes. Accordingly, the relationship between the diffusion kinetics and electrochemical performance of alloying anodes is discussed, combined with efficient strategies that can be adopted to improve electrochemical properties. Finally, a design overview of next‐generation alloying anodes that can extend the batteries’ performance limit is proposed.

We synthesized (+)-decursin derivatives substituted with cinnamoyl- and phenyl propionyl groups originating from (+)-CGK062 and screened them using a cell-based assay to detect relative luciferase reporter activity. Of this series, compound 8b, in which a 3-acetoxy cinnamoyl group was introduced, most potently inhibited (97.0%) the Wnt/β-catenin pathway. Specifically, compound 8b dose-dependently inhibited Wnt3a-induced expression of the β-catenin response transcription (CRT) and increased β-catenin degradation in HEK293 reporter cells. Furthermore, compound 8b suppressed expression of the downstream β-catenin target genes cyclin D1 and c-myc and suppressed PC3 cell growth in a concentration-dependent manner.

We report the results of tensile experiments on 900 nm sputter-deposited films of ZrB 2 , performed at temperatures ranging from ambient to 1016 K. The ZrB 2 samples were tested using micromachined sample frames with integrated micro-heaters. Transmission electron microscopy shows that both as-deposited films and films heated above 1000 K consist of two distinct layers, an amorphous layer and a crystalline layer with a very fine columnar structure. The ZrB 2 films have a room-temperature tensile strength in excess of 1.2 GPa, far exceeding the tensile strength of bulk ZrB 2 , but their stiffness is lower and decreases significantly with increasing temperature. The reduction in stiffness is attributed to the presence of the amorphous phase and the high density of transverse grain boundaries in the crystalline region. The fracture toughness of the ZrB 2 films was measured by introducing pre-cracks in the tensile specimens with a focused ion beam, and was found to be 2.57 ± 0.03 MPa√m, similar to values reported for bulk ZrB 2 .

Increased investments and development of new technologies in drug discovery have barely improved the outcome of medicinal entities in the drug discovery market from a long time. Minimal success rates of drug approvals, poor safety profiles, and long development processes are some of many hurdles encountered in the drug discovery field. Therefore, drug repurposing can provide an alternative approach to meet the demands of the new, potent and safe anti-cancer agents in terms of both economic cost and time efficiency. The common molecular pathways of different diseases and secondary indications of most of the approved drugs, and advances in genomics, informatics and biology, as well as the availability of approved or safe drug libraries can certainly provide an improved and efficient way of screening safer drugs for new indications. Promising results of drug repurposing in different therapeutic areas have encouraged the scientific community to discover new drugs for different diseases using this methodology. Herein, we provide a general overview of structurally and functionally diverse approved drugs that have been repurposed as anti-cancer drugs.

Novel 4′-C-ethynyl isomeric dioxolane nucleoside analogues (β- d , α- d , β- l , and α- l , respectively) are successfully synthesized via a divergent strategy from the common starting material, (Z)-but-2-ene-1,4-diol, and are characterized and evaluated for their anti-HIV-1 and anti-HIV-2 activities. The β- d and β- l products display potent in vitro activities against HIV-1 (IIIB) with EC50 values of 0.75 and 0.87 μM, respectively, and against HIV-2 (ROD) with EC50 values of 0.75 and 0.35 μM, respectively, being better in comparison with 3TC [EC50, 5.27 μM (HIV-1) and 1.30 μM (HIV-2)]. The β- d and β- l nucleosides also potently inhibit different drug-resistant strains of the HIV-1 virus (L100I, K103N, Y181C, and V106A). The selectivity indices and cytotoxic profiles of the β- d and β- l nucleosides are much better than those of the standard drugs AZT and d4T.

We measure stresses that develop in sputter-deposited amorphous Ge thin films during electrochemical lithiation and delithiation. Amorphous LixGe electrodes are found to flow plastically at stresses that are significantly smaller than those of their amorphous LixSi counterparts. The stress measurements allow for quantification of the elastic modulus of amorphous LixGe as a function of lithium concentration, indicating a much-reduced stiffness compared to pure Ge. Additionally, we observe that thinner films of Ge survive a cycle of lithiation and delithiation, whereas thicker films fracture. By monitoring the critical conditions for crack formation, the fracture energy is calculated using an analysis from fracture mechanics. The fracture energies are determined to be Γ = 8.0 J m−2 for a-Li0.3Ge and Γ = 5.6 J m−2 for a-Li1.6Ge. These values are similar to the fracture energy of pure Ge and are typical for brittle fracture. Despite being brittle, the ability of amorphous LixGe to flow at relatively small stresses during lithiation results in an enhanced ability of Ge electrodes to endure electrochemical cycling without fracture.

This study was performed to ascertain the potential of egg plant for use as a trap plant to attract Bemisia tabaci adults compared to that of tomato. Choice tests were conducted to compare the preference of B. tabaci adults to horseweed, egg-plant, cucumber, and tomato. B. tabaci adults were found to be more sensitive to visual cues than to odor cues, and they preferred the egg-plant and cucumber to horseweed. The attraction rates of the egg-plant and cucumber to B. tabaci adults were 82.3% and 82.5% respectively, compared to that of tomato. Because egg-plants are easier to manage compared to cucumber, we excluded cucumber from subsequent experiment. The attraction rate of egg-plant to B. tabaci adults was >90% when the height of egg-plant was equal or more than that of the tomato plant.

Author(s): Byeon, YW; Choi, YS; Seo, JH; Hur, KH; Ahn, JP; Lee, JC | Abstract: © The Korean Institute of Metals and Materials. Anode materials of the Na-Sn battery experience a series of phase transitions during charging and discharging. These phase transitions in many cases are accompanied by a large volume change in the electrode materials, which leads to pulverization, a major source of reducing the battery capacity. In contrast to the rich literature on the phase transition behaviors of the Li-Si battery, those of the Na-Sn battery are much less understood due to experimental difficulties in determining the chemical composition of the phases. In this study, we demonstrate a simple method of analyzing the composition of the reaction compounds of the Na-Sn battery electrodes using energy dispersive X-ray spectroscopy.

We have measured the fracture energy of lithiated silicon thin-film electrodes as a function of lithium concentration using a bending test. First, silicon thin-films on copper substrates were lithiated to various states of charge. Then, bending tests were performed by deforming the substrate to a pre-defined shape, producing a variation of the curvature along the length of the electrode. The bending tests allow determination of the critical strains at which cracks initiate in the lithiated silicon. Using the substrate curvature technique, we also measured the elastic moduli and the stresses that develop in the electrodes during electrochemical lithiation. From these measurements, the fracture energy was calculated as a function of lithium concentration using a finite element simulation of fracture of an elastic film on an elastic–plastic substrate. The fracture energy was determined to be Γ = 12.0 ± 3.0 J m−2 for amorphous silicon and Γ = 10.0 ± 3.6 J m−2 for Li3.28Si, with little variation in the fracture energy for intermediate Li concentrations. These results provide a guideline for the practical design of high-capacity lithium ion batteries to avoid fracture. The experimental technique described in this paper also provides a simple means of measuring the fracture energy of brittle thin-films.

Diffusion in alloying anode materials was previously viewed as solute diffusion in conventional alloys. However, solute diffusion, neglecting the presence of a thin intermediate reaction layer between the unreacted anode material and inflowing carrier ions, is insufficient to account for the diffusion kinetics in alloying anodes and their influence on the electrochemical properties of batteries. Here, by performing a comparative study on Na-Sb and Na-Sn battery systems displaying differing diffusion kinetics, we establish the relationship between diffusion kinetics and electrochemical properties for batteries. In situ microelectrochemical experiments show that sodiation in Na-Sb and Na-Sn systems is governed by an interface-controlled reaction (ICR) and a diffusion-controlled reaction (DCR), respectively, causing them to display significantly different diffusion rates, diffusion anisotropy, and possibly self-limiting diffusion of carrier ions. Density functional theory calculations are performed to elucidate the structural origin of the observed diffusion behaviors. It is found that the different degrees of structural stability evaluated for the propagating interfaces of the two systems are responsible for the differing diffusion kinetics, which in turn determine the respective diffusion rates and diffusion anisotropy of the anode materials. The present study provides crude yet quantitative guidelines for selecting battery materials and can be used to develop fast-charging batteries with high stability and improved cycle life.

Diacylglycerol acyltransferases (DGATs) play a critical role in the biosynthesis of endogenous triglycerides (TGs) and formation of lipid droplets (LDs) in the liver. In particular, one member of DGATs, DGAT-1 was reported to be an essential host factor for the efficient production of hepatitis C virus (HCV) particles. By utilizing our previously characterized three different groups of twelve DGAT inhibitors, we found that one of the DGAT inhibitors, a 2-((4-adamantylphenoxy) methyl)-N-(furan-2-ylmethyl)-1H-benzo[d]imidazole-5-carboxam (10j) is a potent suppressor of both HCV genome replication and particle production. 10j was able to induce inhibition of these two critical viral functions in a mutually separate manner. Abrogation of the viral genome replication by 10j led to a significant reduction in the viral protein expression as well. Interestingly, we found that its antiviral effect did not depend on the reduction of TG biosynthesis by 10j. This suggests that the inhibitory activity of 10j against DGATs may not be directly related with its antiviral action.

Recent development in mobile electronic devices and electric vehicles requires electrical wires with reduced weight as well as enhanced stability. In addition, since electric energy is mostly generated from power plants located far from its consuming places, mechanically stronger and higher electric power transmission cables are strongly demanded. However, there has been no alternative materials that can practically replace copper materials. Here, we report a method to prepare ultrastrong graphene fibers (GFs)-Cu core-shell wires with significantly enhanced electrical and mechanical properties. The core GFs are synthesized by chemical vapor deposition, followed by electroplating of Cu shells, where the large surface area of GFs in contact with Cu maximizes the mechanical toughness of the core-shell wires. At the same time, the unique electrical and thermal characteristics of graphene allow a ∼10 times higher current density limit, providing more efficient and reliable delivery of electrical energies through the GFs-Cu wires. We believe that our results would be useful to overcome the current limit in electrical wires and cables for lightweight, energy-saving, and high-power applications.

Drug repurposing is a safe and successful pathway to speed up the novel drug discovery and development processes compared with de novo drug discovery approaches. Drug repurposing uses FDA-approved drugs and drugs that failed in clinical trials, which have detailed information on potential toxicity, formulation, and pharmacology. Technical advancements in the informatics, genomics, and biological sciences account for the major success of drug repurposing in identifying secondary indications of existing drugs. Drug repurposing is playing a vital role in filling the gap in the discovery of potential antibiotics. Bacterial infections emerged as an ever-increasing global public health threat by dint of multidrug resistance to existing drugs. This raises the urgent need of development of new antibiotics that can effectively fight multidrug-resistant bacterial infections (MDRBIs). The present review describes the key role of drug repurposing in the development of antibiotics during 2016–2017 and of the details of recently FDA-approved antibiotics, pipeline antibiotics, and antibacterial properties of various FDA-approved drugs of anti-cancer, anti-fungal, anti-hyperlipidemia, antiinflammatory, anti-malarial, anti-parasitic, anti-viral, genetic disorder, immune modulator, etc. Further, in view of combination therapies with the existing antibiotics, their potential for new implications for MDRBIs is discussed. The current review may provide essential data for the development of quick, safe, effective, and novel antibiotics for current needs and suggest acuity in its effective implications for inhibiting MDRBIs by repurposing existing drugs.

As opposed to the common understanding that diffusion into a cubic-structured single crystal is independent of its crystalline orientation, the diffusion of Li to crystalline Si (c-Si) is anisotropic, which acts as the major cause for the fracture of Si anodes in Li-ion batteries. Here, by conducting comprehensive/multi-scale simulation studies based on molecular dynamics and density functional theory, we elucidate how and why Li diffusion in c-Si is anisotropic. We found that Li ions diffuse to c-Si by following a particular atomic-scale space corresponding to the lowest value of the valence orbital in c-Si, causing Li ions to take a tortuous diffusion pathway. The degree of the tortuosity of the pathway differs depending on the crystallographic orientation of Si, and it acts as the major cause for anisotropic lithiation. We also develop a structural parameter that can quantitatively evaluate the orientation dependency of the lithiation of c-Si.

In recent years, the emergence of biologically active compounds that contain a heterocyclic ring has gained a great deal of attention among medicinal chemists. Among these, benzoxazole-based compounds are particularly attractive because of their wide range of pharmacological activities. In this focus review, we highlight recent advancements in the development of benzoxazole-based pharmacologically active compounds since the year 2000.

IL-6 is a major causative factor of inflammatory disease. Although IL-6 and its signaling pathways are promising targets, orally available small-molecule drugs specific for IL-6 have not been developed. To discover IL-6 antagonists, we screened our in-house chemical library and identified LMT-28, a novel synthetic compound, as a candidate IL-6 blocker. The activity, mechanism of action, and direct molecular target of LMT-28 were investigated. A reporter gene assay showed that LMT-28 suppressed activation of STAT3 induced by IL-6, but not activation induced by leukemia inhibitory factor. In addition, LMT-28 downregulated IL-6–stimulated phosphorylation of STAT3, gp130, and JAK2 protein and substantially inhibited IL-6–dependent TF-1 cell proliferation. LMT-28 antagonized IL-6–induced TNF-α production in vivo. In pathologic models, oral administration of LMT-28 alleviated collagen-induced arthritis and acute pancreatitis in mice. Based on the observation of upstream IL-6 signal inhibition by LMT-28, we hypothesized IL-6, IL-6Rα, or gp130 to be putative molecular targets. We subsequently demonstrated direct interaction of LMT-28 with gp130 and specific reduction of IL-6/IL-6Rα complex binding to gp130 in the presence of LMT-28, which was measured by surface plasmon resonance analysis. Taken together, our data suggest that LMT-28 is a novel synthetic IL-6 inhibitor that functions through direct binding to gp130.

We report an ultraclean, cost-effective, and easily scalable method of transferring and patterning large-area graphene using pressure sensitive adhesive films (PSAFs) at room temperature. This simple transfer is enabled by the difference in wettability and adhesion energy of graphene with respect to PSAF and a target substrate. The PSAF-transferred graphene is found to be free from residues and shows excellent charge carrier mobility as high as ∼17,700 cm(2)/V·s with less doping compared to the graphene transferred by thermal release tape (TRT) or poly(methyl methacrylate) (PMMA) as well as good uniformity over large areas. In addition, the sheet resistance of graphene transferred by recycled PSAF does not change considerably up to 4 times, which would be advantageous for more cost-effective and environmentally friendly production of large-area graphene films for practical applications.

Mean densities of two-spotted spider mite (TSM), Tetranichus urticae Koch adults from January to April in 2014 to investigate the occurrence and dispersion pattern of T. urticae on purpose of developing a monitoring method in the strawberry PVC house. Difference of density of T. urticae adult on middle and both side of leaf wasn’t significantly. Density of T. urticae in investigation at different furrows and investigating points was the highest at the right and left sides of a furrow in strawberry PVC house. In results of comparing the dispersion incides of Taylor’s power law (TPL) with Iwao’s patchiness regression (IPR), TPL described better mean-relationship for the dispersion indieces compared to IPR. Slopes and intercepts of TPL from leaf samples did not differ among surveyed regions. Also, Distribution of T. urticae in a strawberry PVC house was the gravitation of the distribution because b and β values of TPL and IPR was bigger than 1.

This study reports a direct observation on the crack behavior of lithiated Si wafer. Three different Si wafers with , and axes are investigated, to compare the crack behaviors of different orientation Si wafers. Electrochemically induced cracks in each orientated wafer have dissimilar crack behaviors, because the initiations and propagations of cracks are strongly affected by their orientation and strain energy release rate. It is also found that triangular humps and cracks are formed in the (111) wafer, which are discovered for the first time by in this study. Considering that volume expansion, cracks, and pulverizations of Si are the main issues for the commercial use of Si for Li ion battery, this study provides important insight that is relevant to the design of advanced Si anode materials.

We report observations of microstructural changes in {100} and {110} oriented silicon wafers during initial lithiation under relatively high current densities. Evolution of the microstructure during lithiation was found to depend on the crystallographic orientation of the silicon wafers. In {110} silicon wafers, the phase boundary between silicon and LixSi remained flat and parallel to the surface. In contrast, lithiation of the {100} oriented substrate resulted in a complex vein-like microstructure of LixSi in a crystalline silicon matrix. A simple calculation demonstrates that the formation of such structures is energetically unfavorable in the absence of defects due to the large hydrostatic stresses that develop. However, TEM observations revealed micro-cracks in the {100} silicon wafer, which can create fast diffusion paths for lithium and contribute to the formation of a complex vein-like LixSi network. This defect-induced microstructure can significantly affect the subsequent delithiation and following cycles, resulting in degradation of the electrode.

In tall building construction, the adoption of the appropriate construction method for the core structure process is critical in terms of both the structural aspect of the building and the schedule estimation. This study introduces a new core structure succeeding construction method (CSSCM) for tall buildings with steel-reinforced concrete structures to address the obstacles of the existing core structure preceding construction method (CSPCM) such as limited workspace, interference between activities, difficulties in wall and slab joint construction, and similar obstacles. The study also shows the technical details and compares the results from the applications of CSPCM and CSSCM to an actual tall building project. The results revealed that this method has potential as a cost-effective construction method for structural frameworks of tall buildings where short cycle times are required. In addition, the method provided stable working environments for the steel erection including outriggers and core...

Ethylmercury (EtHg) is derived from the degradation of thimerosal, the most widely used organomercury compound. In this study, EtHg-induced toxicity and autophagy in the mouse kidney was observed and then the mechanism of toxicity was explored in vitro in HK-2 cells. Low doses of EtHg induced autophagy without causing any histopathological changes in mouse kidneys. However, mice treated with high doses of EtHg exhibited severe focal tubular cell necrosis of the proximal tubules with autophagy. EtHg dose-dependently increased the production of reactive oxygen species, reduced the mitochondrial membrane potential, activated the unfolded protein response, and increased cytosolic Ca2+ levels in HK-2 cells. Cell death induced by EtHg exposure was caused by autophagy and necrosis. N-acetyl cysteine and 4-phenylbutyric acid attenuated EtHg-induced stress and ameliorated the autophagic response in HK-2 cells. Furthermore, EtHg blocked autophagosome fusion with lysosomes, which was demonstrated via treatment with wortmannin and chloroquine. Low doses of EtHg and rapamycin, which resulted in minimal cytotoxicity, increased the levels of the autophagic SNARE complex STX17 (syntaxin 17)-VAMP8-SNAP29 without altering mRNA levels, but high dose of EtHg was cytotoxic. Inhibition of autophagic flux by chloroquin increased autophagosome formation and necrotic cell death in HK-2 cells. Collectively, our results show that EtHg induces autophagy via oxidative and ER stress and blockade of autophagic flux. Autophagy might play a dual role in EtHg-induced renal toxicity, being both protective following treatment with low doses of EtHg and detrimental following treatment with high doses.

Three central themes in the study of the phenomenon of resistive switching are the nature of the conducting phase, why it forms, and how it forms. In this study, the answers to all three questions are provided by performing switching experiments in situ in a transmission electron microscope on thin films of the model system polycrystalline SrTiO3 . On the basis of high-resolution transmission electron microscopy, electron-energy-loss spectroscopy and in situ current-voltage measurements, the conducting phase is identified to be SrTi11 O20 . This phase is only observed at specific grain boundaries, and a Ruddlesden-Popper phase, Sr3 Ti2 O7 , is typically observed adjacent to the conducting phase. These results allow not only the proposal that filament formation in this system has a thermodynamic origin-it is driven by electrochemical polarization and the local oxygen activity in the film decreasing below a critical value-but also the deduction of a phase diagram for strongly reduced SrTiO3 . Furthermore, why many conducting filaments are nucleated at one electrode but only one filament wins the race to the opposite electrode is also explained. The work thus provides detailed insights into the origin and mechanisms of filament generation and rupture.

Dynamic recrystallization (DRX) of 99.9999% aluminum single crystal at room temperature was examined under frictionless deformation mode. To exclude the self-heating of the specimen due to applied high strain, a microcrack that localizes the stress at a very small region was intentionally introduced by controlled local necking. For the in situ observation of DRX, a specially designed in situ microdeformation device was positioned inside an electron backscattered diffraction system chamber. Recrystallized grains showed relatively random texture and preferred growth direction. The subgrains with low-angle grain boundaries formed by dynamic recovery transformed into small grains with high-angle grain boundaries, acting as nuclei for discontinuous dynamic recrystallization and growing by further deformation. The DRX in pure aluminum can take place under frictionless tensile deformation conditions at room temperature, and the stress localization and high purity are key issues for the DRX of aluminum at room temperature.

The deformation behavior of duplex low-density steel was analyzed by correlation between macroscale uniaxial tension and nanoscale indentation. A dramatic difference in the tensile behavior was observed between two specimens obtained under specific heat-treatment conditions, despite these specimens having the same chemical composition and similar microstructures. In order to understand this difference, the intrinsic mechanical properties of each phase were analyzed based on nanoindentation results considering the Hall–Petch relationship. In addition, the mechanical stability of retained austenite was investigated by in situ electron backscattered diffraction.

A series of novel (1S)-(-)-verbenone derivatives was synthesized bearing a 4-styryl scaffold. The synthesized compounds were tested for their anti-oxidant, anti-excitotoxic, and anti-ischemic activities. These derivatives significantly reduced oxygen-glucose deprivation-induced neuronal injury and N-methyl-D-aspartic acid-evoked excitotoxicity in cortical neurons. Furthermore, compound 3f was identified as a potent anti-ischemic agent in an in vitro ischemic model, potentially due to the inhibition of N-methyl-D-aspartic acid-evoked excitotoxicity and oxidative/nitrosative stress.

The effects of proton irradiation on a beryllium reflector in terms of microstructure evolution have been studied to emulate the effects of neutron irradiation. Protons were irradiated on a beryllium sample with the acceleration voltage of 120 keV and the fluence of 2.0 × 1018 ions/cm2 at room temperature. The size of the irradiation damaged layer was estimated through a Monte Carlo simulation (SRIM2012 software) and transmission electron microscopy (TEM) observation. While the irradiated sample was observed by using TEM, the size of the damaged layer was roughly 1 µm, and the value was coincident with the simulation result. The most severely damaged area was occurred at 600 nm in depth; tens-of-nanometer-sized voids were distributed. Multiple voids were observed in the entire damaged area, and were preferentially distributed along the grain boundaries, and the interfaces between the matrix and the BeO particles. Equi-axed voids, 10 nm in diameter, were observed in the grain boundary, and planar voids were observed at the interfaces. The voids were also distributed in the grains; the evolutions of the voids were observed to have been affected by the grain orientation rather than the irradiation direction. The selective area diffraction pattern (SADP) from TEM showed that the arrays of multiple voids were considerably longer along the basal plane. The beryllium atoms could be easily dislocated by proton irradiation while the basal plane was aligned along a direction perpendicular to the irradiation.

With the increasing demand for instant real-time ultrasound (US) imaging of a specific organ, target-specific and long-circulating ultrasound contrast agents are of special interest. A new species of echogenic hyaluronic acid nanoparticles is presented as an ultralong-acting, liver-specific, US contrast agent that is distinct from conventional gas-filled microbubbles. Using an oil-in-water (O/W) emulsification method, bioinert and hydrophobic perfluoropentane (PFP) is encapsulated as an ultrasound gas precursor into hyaluronic acid nanoparticles (HANPs) using hydrophobic interactions. HANPs are formulated by self-assembly, with amphiphilic hyaluronic acid-5β-cholanic acid (HA-CA) conjugating in aqueous conditions. The resulting echogenic PFP-encapsulated HANPs (Echo-NPs) show solid nanostructures, differentiated from core-empty conventional microbubbles, and exhibiting outstanding physical properties as an ultrasound contrast agent. They are more stable and robust echogenic solid bodies with an in vivo favorable hydrodynamic size and because PFPs vaporize gradually, their expansion process is very slow in body conditions. After several systemic circulations, echo-NPs generated intense and ultralong echo signals for US imaging at the target site. The echogenic properties of Echo-NPs show a significantly increased half-life and echo persistence, compared with conventional microbubbles. The results clearly show that echo-NPs outperform conventional microbubbles in terms of both physical and echogenic in vitro and in vivo properties.

Here, we report a cationic nanolipoplex as a pulmonary cellular delivery system for small-interfering RNA (siRNA). Six nanoliposomes differing in cationic lipids were formulated and screened in vitro and in vivo for cellular delivery functions in lung cells/tissues. Although the six nanoliposomes showed similar siRNA delivery efficiency in vitro, they exhibited significant differences in pulmonary cellular delivery functions in vivo. Among the various nanoliposomes, cationic dioleoyl-sn-glycero-3-ethylphosphocholine and cholesterol (ECL)-based nanoliposomes showed the highest pulmonary cellular delivery in vivo and the lowest cytotoxicity in vitro. The delivery efficiency of fluorescent siRNA in ECL nanoliposomes was 26.2-fold higher than that of naked siRNA in vivo. Treatment with Mcl1 (myeloid cell leukemia sequence 1)-specific siRNA (siMcl1) using ECL nanolipoplexes reduced target expression in B16F10 cell lines, whereas control, luciferase-specific siGL2 in ECL nanolipoplexes did not. In metastatic lung cancer mouse models induced by B16F10 or Lewis lung carcinoma (LLC) cells, intratracheal administration of siMcl1 in ECL nanolipoplexes significantly silenced Mcl1 mRNA and protein levels in lung tissue. Reduced formation of melanoma tumor nodules was observed in the lung. These results demonstrate the utility of ECL nanoliposomes for pulmonary delivery of therapeutic siRNA for the treatment of lung cancers and potentially for other respiratory diseases.

We report the usage of ZnO material as an alternative for n-GaN for realizing III-nitride based solar cell. The fabricated solar cell shows large turn-on voltage of around 8 volts and a rapid decrease of photocurrent at low bias voltage under darkness and 1-sun illumination conditions, respectively. This phenomenon can be attributed to the formation of high-resistive ultra-thin layers at the ZnO/ p-GaN junction interface during high temperature deposition. Transmission electron microscopy (TEM) studies carried out on the grown samples reveals that the ultra-thin layer consists of ZnGa2O4. It is found that the presence of insulating ZnGa2O4 film is detrimental in the performance of proposed heterostructure for solar cells.

PURPOSES : This paper aims to improve the evaluation method of the Level of Service(LOS) for urban streets presented by the current Korean Highway Capacity Manual(KHCM) and suggest its utilization plan as a part of the methods to evaluate the sustainability of a transportation policy. METHODS : This paper carried out a research in 3 steps to develop a new evaluation method. First of all, this paper reviewed the previous studies related to the LOS of urban streets and the socially requested items for a sustainable transportation system. Then this paper derived an index and weight through expert questions to select an evaluation index. Lastly, this paper compared the results according to the existing evaluation methods with the new evaluation methods through case studies. This paper used an Analytic Hierarchy Process(AHP) for importance analysis and weight selection between new evaluation items and indices, and applied a Grey System Theory(GST) for a synthetic and integrated evaluation between the selected evaluation indices. RESULTS : As a result of evaluating the LOS according to the existing evaluation methods and the integrated evaluation methods using a GST through case studies, it was analyzed that new methods` results are less than or equal to the existing evaluation methods; and as a result of applying a weight between evaluation indices according to AHP, it was noticed that the total score seems to rise more when the LOS in the existing evaluation is calculated lower. It was analyzed that the LOS calculated by reflecting the newly established evaluation items and the importance between indices in this study has difference from the LOS of the existing urban streets. CONCLUSIONS : It is expected that this evaluation method can diagnose the current conditions when establishing a future sustainable traffic system and can be used for the measurement of the sustainability effects of the improvement plans and so on.

A novel series of benzimidazole derivatives was prepared and evaluated for their diacylglycerol acyltransferase (DGAT) inhibitory activity using microsome from rat liver. Among the newly synthesized compounds, furfurylamine containing benzimidazole carboxamide 10j showed the most potent DGAT inhibitory effect (IC50 = 4.4 μM) and inhibited triglyceride formation in HepG2 cells. Furthermore, compound 10j reduced body weight gain of Institute of Cancer Research mice on a high-fat diet and decreased levels of total triglyceride, total cholesterol, and LDL-cholesterol in the blood accompanied with a significant increase in HDL-cholesterol level.

Nanoparticles have demonstrated potential for promoting drug delivery to tumor sites and enhancing uptake. Here, we report tetraiodothyroacetic acid (tetrac) as a promising new targeting moiety for delivery of anticancer drugs to tumor tissues. Tetrac, an antagonist that blocks the binding of thyroid hormone to integrin αvβ3, was covalently linked to the activated end of pegylated lipid and used to formulate tetrac-tagged pegylated liposomes (TPL). After incubating with TPL for 9 h, cellular accumulation efficiency into A375 human melanoma cells, which express integrin αvβ3 at high density, was high (98.5% ± 0.5% of cells), whereas that in KB cells, which express integrin at a very low density, was much lower (35.1% ± 4.5%). Molecular imaging revealed that TPL preferentially distributed to tumor tissues after systemic administration in mice, where as non-targeting pegylated liposomes were distributed to tumors at background levels. Treatment with the alkyl lysophospholipid anticancer drug edelfosine, encapsulated in TPL, significantly reduced the survival of A375 tumor cells compared to cells treated with edelfosine in pegylated liposomes or with lysophosphatidylcholine encapsulated in TPL. Moreover, intravenous administration of edelfosine in TPL significantly reduced the growth of tumors and prolonged the survival of A375-xenografted mice, providing 100% protection for up to 50 days and some protection until 66 days (0% survival endpoint). In contrast, no untreated mice or mice treated with edelfosine-loaded pegylated liposomes survived up to 50 or 48 days, respectively, after tumor inoculation. These results suggest the potential of tetrac as a new ligand moiety for enhancing the delivery of anticancer drug-loaded nanoparticles to tumors and enhancing the therapeutic efficacy of encapsulated anticancer drugs.