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We present a quantum-correlation-based free-space optical(FSO) link over 250 m using an outdoor active reflector 125 m from the transceiver station. The performance of free-space optical communication can be significantly degraded by atmospheric turbulence effects, such as beam wander and signal fluctuations. We used a 660 nm tracking laser to reduce atmospheric effects, by analyzing the fast beam wander and slow temporal beam drift, using this information to correct the quantum channel alignment of the 810 nm signal photons. In this work, the active reflector consisted of a mirror, a 6-axis hexapod stage, and a long-range wireless bridge. The slow drift of the beam path due to outdoor temperature changes was steered and controlled using wireless optical feedback between the receiver units and the active reflector. Our work provides useful knowledge for improved control of beam paths in outdoor conditions, which can be developed to ensure high quality quantum information transfer in real-world scenarios, such as an unmanned FSO link for urban quantum communication or retro-reflective quantum communication links., Comment: 8 pages, 6 figures

Solid polymer electrolyte gate dielectric based on cross-linked poly(ethylene oxide) (CPEO) was developed and employed for organic thin-film transistors (OTFTs). Mechanical stability, high areal capacitance, and amorphous morphology of CPEO were achieved via the use of polyhedral oligomeric silsesquioxane (POSS) as cross-linker, dissolved ion [EMIM][TFSI] as electrolyte, and PEO with low molecular weight as polymer matrix, respectively. The resulting solid polymer electrolyte showed excellent insulating properties with low leakage current density (1.8 × 10−7 A cm−2 at 1 V) and high capacitance per area (∼ 1 μF cm−2 at 100 Hz). Furthermore, dielectric properties of the developed polymer electrolytes including ionic conductivity as well as segmental relaxation time were investigated. The polyelectrolyte dielectric was employed for bottom-gate/top-contact organic thin-film transistors and the resulting devices showed decent electrical performance with a carrier mobility of 0.12 (±0.03) cm2 V−1 s−1 and a current on/off ratio of 103 at low operating voltage of 5 V.

In recent years, some researchers have been interested in whether robustness and blindness can be simultaneously secured in a watermarking based on machine learning. However, achieving robustness against various attacks at once is still difficult for watermarking techniques. To address the problem, in this paper, we propose a learning framework for robust and blind watermarking based on reinforcement learning. We repeat three stages: watermark embedding, attack simulation, and weight updating. Specifically, we present image watermarking networks called WMNet using convolutional neural networks (CNNs). Two methods to embed a watermark are proposed and these two methods are based on backpropagation and autoencoder, respectively. We can optimize the robustness while carefully considering the invisibility of the watermarking system. The experimental results show that the trained WMNet captures more robust features than the current watermarking schemes, which use the frequency domain. The trade-off between the robustness and the invisibility of each technique was measured. Also, we adopt a visual masking with which we can achieve the appropriate balance between robustness and invisibility of the watermark. Our reinforcement-learning-based technique has better robustness than the existing techniques for both attacks seen in learning and unseen attacks. Due to the generalization ability of WMNet, moreover, it shows high robustness against multiple attacks and various levels of attacks which are not considered in training stage.

Novel polyurethane triblock copolymers comprising polycaprolactone diol (PCL), 1,6-hexamethylene diisocyanate (HMDI), and polyethylene glycol (PEG) were synthesized for use as gate dielectric for organic thin-film transistors (OTFTs). Thin films of polyurethane gate dielectrics processed from solution exhibit excellent insulating properties (∼7 × 10−7 A/cm2 at 1 V) as well as large areal capacitance (170 nF/cm2) with film thickness of ∼50 nm. OTFTs are fabricated with representative n-channel organic semiconductor (N,N′-ditridecylperylene-3,4,9,10-tetracarboxylic diimide; PTCDI-C13) using the developed gate dielectrics, and the resulting devices show decent electrical performance with negligible hysteresis at low operating voltage of 1 V.

The protective coating layer for accident tolerance fuels (ATF) will offer a fuel efficient, enhanced oxidation resistance of zirconium alloy, and safe operation by active cooling of the reactor. The various coating methods on the surface of zirconium alloy such as physical vapor deposition, chemical vapor deposition, and cold spray have been tried to optimize the thin film layer for enhanced ATF performance. Among them, physical vapor deposition is a potential candidate for ATF coating layer due to its low temperature process ensuring mechanical strength of zircaloy cladding during coating process. The silicon carbide (SiC) is promising for extremely high irradiation doses, which provide saturated swelling after a few months of typical operation. As alternative claddings, SiC with various concentration of Si has been deposited on zircaloy cladding for the oxidation resistances. It has been tested at 900 °C for 500 h in steam environment. The enhancement of oxidation resistance of SiC/Si composite coating layer was attributed to an oxidation of Si component to SiOx during steam environments.

Chromium and chromium nitride were selected as potential barriers to prevent fuel-clad chemical interaction (FCCI) between the cladding and the fuel material. In this study, ferritic/martensitic HT-9 steel and misch metal were used to simulate the reaction between the cladding and fuel fission product, respectively. Radio frequency magnetron sputtering was used to deposit Cr and CrN films onto the cladding, and the gas flow rates of argon and nitrogen were fixed at certain values for each sample to control the deposition rate and the crystal structure of the films. The samples were heated for 24 h at 933 K through the diffusion couple test, and considerable amount of interdiffusion (max. thickness: 550 μm) occurred at the interface between HT-9 and misch metal when the argon and nitrogen were used individually. The elemental contents of misch metal were detected at the HT-9 through energy dispersive X-ray spectroscopy due to the interdiffusion. However, the specimens that were sputtered by mixed gases (Ar and N2) exhibited excellent resistance to FCCI. The thickness of these CrN films were only 4 μm, but these films effectively prevented the FCCI due to their high adhesion strength (frictional force ≥1,200 μm) and dense columnar microstructures. Keywords: CrN, Fuel-Clad Chemical Interaction Barrier, Interdiffusion, Scratch Test

Aim This study evaluated the association of Heart rate variability (HRV) measurements with diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes. Methods This study included 102 Korean subjects with type 2 diabetes. The Michigan neuropathy screening instrument (MNSI) questionnaire score, the MNSI examination score (MNSIES) and the total symptom score were examined for DPN evaluation. Noninvasive HRV measurements were performed using photoelectric plethysmography. Patients with a MNSIES > 2 were considered to have DPN. Results The MNSIES showed significant negative associations with the high frequency (HF) (r = −0.212, p = 0.033) and low frequency (LF) (r = −0.286, p = 0.004) powers. Multiple linear regression analysis revealed that only HF power maintained a significant negative association with the MNSIES (β = −0.184; 95% CI −0.365 to −0.003; p = 0.047), after controlling for significant related confounders, with HRV parameters in male patients with type 2 diabetes. The HF (p = 0.010) and LF (p = 0.025) powers differed significantly between male patients without and those with DPN according to the MNSIES. Conclusions This study revealed a negative association of DPN, as assessed by the MNSIES, with HF power in male patients with type 2 diabetes. DPN defined by foot examination was predictive of cardiac autonomic neuropathy.

Recently, redox-mediated deionization (Redox-DI) has emerged as a promising ion separation process owing to its sustainable ion removal performance and feasibility. The characteristic cell configuration of Redox-DI involves two independent channels for treating water and supporting electrolytes containing redox couples in a multichannel system. This leads to continuous desalination mediated by a sustainable redox reaction on porous carbon electrodes, which is the preferred material in Redox-DI since it governs energy efficiency and ion removal performance. In particular, the activated carbon cloth (ACC) is a promising electrode due to its attractive features including simple shaping as a binder-free electrode and a large inter-fiber space assisting active mass transfer. However, very few studies have reported on the advancement of redox reactions on ACC electrodes, including electrocatalytic activity and rate capability. Therefore, this study aimed to produce a simple nitrogen-doped porous carbon cloth (N-ACC) electrode to improve the electrocatalytic activity for redox reactions, resulting in enhanced desalination performance of Redox-DI. The nitrogen content in N-ACC increased to approximately 3 at.% and was uniformly distributed on the surface of ACC using urea as a nitrogen source at mild temperature of 300 °C. N-ACC showed remarkable desalination performance with a salt removal rate (SRR) of 69.1 mg/g-h, a charge efficiency of 95.3%, and energy consumption of 122.0 kJ/mol. This is a 58.3% improvement in the SRR compared to ACC. In addition, through a parametric investigation with different cell voltages and flow rates, a high SRR (70–80 mg/g-h) and charge efficiency (90–100%) of N-ACC was demonstrated. N-doped ACC enhances the electrocatalytic activity, including fast reaction kinetics and low charge transfer resistance to redox couple reactions.

In the present work, a new methodology for improving the ionic conductivity and cation transport properties of polymer electrolytes have been synthesized by adding bulky anion based novel lithium bisnonafluoro-1-butanesulfonimidate salt and characterized for its applications in lithium ion batteries. The self-standing solid polymer electrolyte films exhibit excellent mechanical, thermal, and electrochemical stability. The ion–polymer interactions are examined thoroughly by ATR Fourier Transform-Infra Red Spectroscopy. The solid polymer electrolyte prepared with EO/Li ratio 14 exhibits a highest ionic conductivity of 10−4 S cm−1 at 333 K. Also, it achieves a maximum lithium transference number of 0.31 and it is electrochemically stable in the scanned electrochemical window. This new type of polymer electrolytes with high ion conductivity and improved mechanical properties paves way to be a potential candidate along with lithium anode and LiCoO2 cathode in the lithium ion batteries.

For the first time, the consequences of organic-inorganic hybrid nanoparticle polyhedral oligomeric silsesquioxane-polyethylene glycol (POSS-PEG(n = 4)) on the physicochemical and electrochemical properties of poly(ethylene oxide) (PEO)-lithium difluoro(oxalato)borate (LiDFOB) based nanocomposite solid polymer electrolyte (NSPE) membranes were systematically prepared and utilized as an active separator for battery applications. The thermal stability and structural properties of the prepared NSPE membranes were analyzed by means of differential scanning calorimetry (DSC), thermogravimetry (TG) and X-ray diffraction (XRD) analyses. The morphological changes by POSS-PEG in polymer electrolyte membranes were investigated by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The incorporation of POSS-PEG greatly enhanced the ionic conductivity, mechanical integrity and compatibility. The maximum ambient temperature ionic conductivity was found to be in the range of 7.28 × 10−5 S/cm for 40 wt% POSS-PEG. Finally, the solid state lithium cell was assembled as Li/NSPE/LiCoO2. The cell delivered a maximum discharge capacity of 187 mAh g−1 at 0.1C-rate with very good capacity retention up to 50 cycles. The test results indicated that the electrolyte is found to be a better candidate than those reported earlier.

The in-plane and out-of-plane vibration components are used for 3D vibration measurements. The latter can be calculated by using three laser scanning vibrometers (LSVs) or by moving a single LSV to three different locations. These vibration components are calculated from the vibration signals measured at each of the three locations and the angles between the local coordinates and the LSV locations. The accuracy of the in-plane and out-of-plane vibration components can be degraded depending on the measurement angle. In addition to accuracy, the noise contained in the LSV can be amplified depending on the measurement angle. Hence, it is necessary to implement an analysis methodology for the angles, which is conducted for 2D vibration measurements first before extended to 3D. Finally, experiments are performed for both 2D and 3D at small and appropriate angles, and the elicited results are compared to those elicited using a 3D accelerometer.

Gene therapy is aimed at selectively knocking up or knocking down the target genes involved in the development of diseases. In many human diseases, dysregulation of disease-associated genes is occurred concurrently: some genes are abnormally turned up and some are turned down. In the field of non-viral gene therapy, plasmid DNA (pDNA) and small interfering RNA (siRNA) are suggested as representative regulation tools for activating and silencing the expression of genes of interest, representatively. Herein, we simultaneously loaded both siRNA (Src homology region 2 domain-containing tyrosine phosphatase-1 siRNA, siSHP-1) for anti-apoptosis and pDNA (hypoxia-inducible vascular endothelial growth factor expression vector, pHI-VEGF) for angiogenesis in a single polymeric nanocarrier and used to synergistically attenuate ischemia-reperfusion (IR)-induced myocardial infarction, which is mainly caused by dysregulating of cardiac apoptosis and angiogenesis. For dual-modality cardiac gene delivery, siSHP-1 and pHI-VEGF were sequentially incorporated into a stable nanocomplex by using deoxycholic acid-modified polyethylenimine (DA-PEI). The resulting DA-PEI/siSHP-1/pHI-VEGF complexes exhibited the high structural stability against polyanion competition and the improved resistance to digestion by nucleases. The cardiac administration of DA-PEI/siSHP-1/pHI-VEGF reduced cardiomyocyte apoptosis and enhanced cardiac microvessel formation, thereby reducing infarct size in rat ischemia-reperfusion model. The simultaneous anti-apoptotic and angiogenic gene therapies synergized the cardioprotective effects of each strategy; thus our dual-modal single-carrier gene delivery system can be considered as a promising candidate for treating ischemic heart diseases.

Fine-tuning the nanochannels of ion conducting membrane is the key to achieving high performance electrochemical devices. Here, we describe an effective way to enhance the membrane performance using heterocyclic imidazole compound as an additive for Nafion. The hygroscopic nature of the imidazole offered sufficient amount of water molecules to the nanochannel of Nafion, affording wider and continuous nanochannel configuration, as characterized by small angle X-ray scattering (SAXS). Moreover, proton conduction was boosted by the hydrogen bonding interaction between the water molecules and two nitrogen atoms on imidazole ring. The developed membrane showed improved proton conductivity up to 23% and 50% under high and low humidity condition, respectively, compared to pristine Nafion. Additionally, the membrane exhibited excellent stability under harsh condition. Finally, we implemented the developed membrane in fuel cell application and the cell showed enhanced power density without performance degradation, compared to that employing pristine Nafion membrane.

The immediate early gene Arc (also Arg3.1) produces rapid changes in synaptic properties that are linked to de novo translation. Here we develop a novel translation reporter that exploits the rapid maturation and "flash" kinetics of Gaussia luciferase (Gluc) to visualize Arc translation. Following glutamate stimulation, discrete Arc-Gluc bioluminescent flashes representing sites of de novo translation are detected within 15 s at distributed sites in dendrites, but not spines. Flashes are episodic, lasting ∼20 s, and may be unitary or repeated at ∼minute intervals at the same sites. Analysis of flash amplitudes suggests they represent the quantal product of one or more polyribosomes, while inter-flash intervals appear random, suggesting they arise from a stochastic process. Surprisingly, glutamate-induced translation is dependent on Arc open reading frame. Combined observations support a model in which stalled ribosomes are reactivated to rapidly generate Arc protein.

New fluorene derivatives with donor-acceptor-donor (D-A-D) structure were synthesized and characterized as solution-processable organic semiconductors for top-contact/bottom-gate organic thin-film transistors (OTFTs). Physicochemical properties of the new compounds were characterized by cyclic voltammetry (CV), UV–vis absorption spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and density functional theory (DFT) calculation. All compounds were TFT active and compounds with strong electron withdrawing groups showed ambipolar semiconductor performance with electron mobility of up to 0.1 cm2 V-1 s-1 and current on/off ratio of > 106.

Expression of receptor for advanced glycation end-products (RAGE) is suggested to play a crucial role in mediating cardiac ischemia/reperfusion (IR) injury, and the blockade of RAGE signaling has been considered as a potential therapeutic strategy for the treatment of IR-induced cardiac damage. In this study, we primarily investigated the effects of RAGE suppression particularly on IR-induced ventricular arrhythmia. To inhibit the IR-induced upregulation of RAGE, siRNA targeting RAGE (siRAGE) was delivered to myocardium by using deoxycholic acid-modified polyethylenimine (PEI-DA) as a non-viral gene carrier. The resultant PEI-DA/siRAGE nanocomplexes successfully silenced the expression of RAGE and attenuated the inflammation and apoptosis in the ischemic-reperfused myocardium. According to our results, the electrophysiological properties (e.g., action potential propagation, action potential duration, and conduction velocity), disrupted by IR injury, were restored to normal level and the induction of ventricular tachycardia was abolished by RAGE silencing. We further found that RAGE suppression led to the activation of Wnt signaling, followed by the expression of gap junction protein, connexin43. Thus it could be concluded that successful siRAGE delivery is protective against IR-induced ventricular arrhythmia.

Electrospun poly(vinylidene fluoride) nanofibers were carbonized with iron(III) acetylacetonate to induce catalytic graphitization within the temperature range 800–1800 °C. Carbonization in the presence of the catalyst produced graphite nanofibers (GNFs). Their structural properties and morphology were investigated. GNFs with a high surface area of 377–473 m2/g showed the typical Type II containing mesopore in nitrogen adsorption–desorption isotherms. The hydrogen storage capacity of these GNFs was evaluated by the gravimetric method using a magnetic suspension balance (MSB) at room temperature and about 80 bar. The hydrogen storage capacity was 0.11–0.18 wt.%. The effective pore size for hydrogen storage compared to the diameter of the hydrogen molecule is discussed.

A base of clearly defined product information is a key foundation for an e-commerce system. The manipulation and exchange of semantically enriched and precise product information can enhance the quality of an e-commerce system and offer a high level of interoperability with other systems. Product information consists of product attributes and the relationships between products. Product categorization (or classification) is one type of such relationships. Ontology can play an important role in the formalization of product information. Although the idea of utilizing ontology for e-Catalogs has been raised before, we are yet to find an operational implementation of applying ontology in the domain. In this paper, we report on our recent effort to build an operational product ontology system for a government procurement service. The system is designed to serve as a product ontology knowledge base; not only for the design and construction of product databases but also for search and discovery of products. Especially, the keyword-based searching over product ontology database demands different techniques from those over conventional document databases or relational databases, and should be designed to reflect particular characteristics of product ontology. We also introduce some other issues that we have experienced in the project, and those issues include product ontology modeling, ontology construction and maintenance, and visualization. Our work presented herein may serve as a reference model for similar projects in the future.