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Since the main flow blades of gas turbines are in high temperature and high pressure condition, their life span depends on the performance of the cooling system. A pre-swirl system is a device that minimizes the flow loss that occurs when the cooling air is introduced into the rotating part from the stationary part by imposing the rotation component in advance. System performance depends on the shape of the pre-swirl nozzle and receiver hole. In this study, the performance trend according to the shape change of a direct injection type pre-swirl system was numerically investigated. First, the performance was examined by varying the system inlet/outlet pressure ratio, from which the optimum flow rate of the system was determined. When a study was conducted by changing the fillet radius of the receiver hole inlet, the larger radius results in greater discharge coefficient, but there was no significant difference for radius ratio greater than 0.13. Rather interestingly, the outlet of the receiver hole without a fillet that does not spread the cooling air produced a high value of temperature drop efficiency. [ABSTRACT FROM AUTHOR]

• The significant of SRT on the hydrolysis rate and maximum uptake rate was confirmed. • The modified ADM1 was validated for AD of intact and thermally hydrolyzed CM. • The effects of thermal hydrolysis pretreatment were analyzed using model simulation. In this study, Anaerobic Digestion Model No.1 (ADM1) was modified to incorporate changes in biochemical parameters due to solids retention time (SRT) variations. Cattle manure (CM) and thermally hydrolyzed CM were selected for testing. Continuous anaerobic digestion reactors were operated under different SRT conditions ranging from 6.6 to 36.0 days for both samples. The biochemical parameters (k ch , k li , k pr , u m , a c , u m , b u , u m , p r o , u m , v a , K ac , K bu , K pro , and K va ) for each SRT condition were determined. To modify ADM1, the equations obtained through linear regression were substituted into biochemical parameters as a function of SRT. The modified ADM1 demonstrated superior accuracy compared with conventional ADM1. This study implies the feasibility of optimizing biochemical parameters for modeling in response to changes in environmental variables. [ABSTRACT FROM AUTHOR]

The effects of simultaneous lanthanum and nickel addition on the oxidation behavior and area-specific resistance (ASR) of stainless steels for fuelcell interconnects were investigated. The La and Ni addition promoted the entire growth of the oxide layer and increased the roughness of the metal/oxide interface. Despite the thicker oxide scale, these alloys prevented the increase of ASR compared to the alloy with only Ni added. The void analysis indicated that simultaneous La and Ni addition could prevent void growth, leading to lower ASR. The above findings can be interpreted in terms of the fast La diffusion and convoluted metal/oxide interface. • La intermetallic close to La 3 Ni were observed in La and Ni-added alloys. • Liquid diffusion was observed due to the low La intermetallic melting temperature. • The fast La diffusion increases oxide growth and the interface roughness. • Despite the thicker oxide scale, ASR increase is prevented. • The addition of La and Ni prevents void growth and improves scale adhesion. [ABSTRACT FROM AUTHOR]

In fuel cell and electrolysis systems, hydrogen crossover is a phenomenon where hydrogen molecules (H 2) permeate through a membrane, lowering the overall process efficiency and generating a potential safety risk. Many works have been reported to mitigate this undesired phenomenon, but it is yet difficult to accurately measure the rate of hydrogen crossover, particularly when the membrane is fully wetted in water. In this work, we investigated the pressure decay method as a simple, convenient, and low-cost method to characterize hydrogen crossover through wetted membranes for water electrolysis systems. Three different ion exchange membranes were analyzed: Nafion 212, Nafion 115, and in-house sulfonated poly(arylene ether sulfone). We rigorously confirmed our method and data by comparing it to the ANSI dataset with the current state-of-the-art equations of state (EOS) to account for the nonideality of high pressure hydrogen systems. The error from the gas non-ideality was less than 0.03%. As expected, the rate of hydrogen crossover showed high dependency on the temperature; more importantly, hydrogen crossover increased significantly when the membrane was fully soaked in water. For dry membranes, the proposed pressure decay method corroborated well with the literature data measured using other known methods. Moreover, for wetted membranes, the obtained data showed high similarity compared to the GC method which is currently the most reliable method in the literature. We attempted to predict the hydrogen permeability of wetted membranes using the solution diffusion model. The model based on the given thermodynamic parameters overestimated the hydrogen permeability, which can be used to estimate the ion channel tortuosity. • The pressure decay method was proposed to characterize hydrogen crossover. • The proposed method is simple, convenient, and low-cost with excellent accuracy. • Hydrogen crossover for wetted membranes can be conveniently measured. • The solution-diffusion transport model overestimates the hydrogen crossover. [ABSTRACT FROM AUTHOR]

Research in the field of organic electronics has witnessed dramatic improvements in device performance over the past several decades through an ever‐improving understanding of electron and hole movement and the development of new interfacial materials. In this study, a type of interfacial material that relies on ionic charges comprising metal:poly(styrenesulfonate) (PSS) polyelectrolytes are synthesized and investigated as structural analogs of the ubiquitously used poly(3,4‐ethylenedioxythiophene:polystyrenesulfonate) (PEDOT:PSS) hole transport layer, in order to investigate correlations between metal cation ions and the cationic PEDOT component. The metal ions selected for this study include Li, Mg, V, Mn, Co, Ni, Cu, Zn, Pd, Ag, Cs, and Pb ions. To analyze the interfacial energy level alignment, electronic band structure, and band bending at the Indium tin oxide (ITO)/metal:PSS interface, X‐ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) are employed. Alkali (earth) and post‐transition metals show deep highest occupied molecular orbital (HOMO) levels and low work function (WF) due to Fermi level balance, implying poor hole transport. Remarkably, Cu:PSS displays a unique electronic structure, suggesting potential as a hole transport layer with increased WF and low hole injection barrier. Period 5 transition metals mirror PEDOT:PSS trends, and Ag:PSS holds the potential to form effective ohmic contacts. [ABSTRACT FROM AUTHOR]

We study the effects of coupling strength inhomogeneity and coupling functions on locking behaviors of coupled identical oscillators, some of which are relatively weakly coupled to others while some are relatively strongly coupled. Through the stability analysis and numerical simulations, we show that several categories of fully locked or partially locked states can emerge and obtain the conditions for these categories. In this system with coupling strength inhomogeneity, locked and drifting subpopulations are determined by the coupling strength distribution and the shape of the coupling functions. Even the strongly coupled oscillators can drift while weakly coupled oscillators can be locked. The simulation results with Gaussian and power-law distributions for coupling strengths are compared and discussed. [ABSTRACT FROM AUTHOR]

Abstract This study aims to develop a mathematical model to estimate the initial permeate flux of a direct contact membrane distillation process operated with various solids concentrations and Cross Flow Velocities (CFVs). Digestate produced from an anaerobic digestion of livestock wastewater was used as a feed solution for the laboratory scale membrane distillation. Heat transfer coefficients and Nusselt number constants were determined from the distillation experiments performed with various CFVs and feed solution temperatures. An empirical function was derived to reflect the effect of solids concentration on the flux prediction. A statistical analysis supported that the flux predicted by the model fitted very well with the observed flux. By using the developed model, numerical experiments were performed to simulate the flux according to various CFVs, feed solution temperatures, and solids concentrations (0–2200 mg/L). Also, Temperature Polarization Coefficient (TPC) values were calculated by using the results simulated from the numerical experiments. The developed model can be used to predict the initial flux of the membrane distillation process specifically to treat wastewater including high solids contents, and the modeling works can provide more insights on the relationship among flux, CFV, temperature difference, solids concentrations, and heat transfer efficiency. Graphical abstract fx1 Highlights • A mathematical model developed to predict the permeate flux of the DCMD process. • Suspended solids had more significant influence on the flux than dissolved solids. • Flux with suspended solids concentration was suggested as J = B { P f 0 (1 − a C ss ) − P p 0 }. • Modeling provided more understandings on the membrane distillation process. [ABSTRACT FROM AUTHOR]

Background: Hypsizygus marmoreus (Beech mushroom) is a popular ingredient in Asian cuisine. The medicinal effects of its bioactive compounds such as hypsin and hypsiziprenol have been reported, but the genetic basis or biosynthesis of these components is unknown. Results: In this study, we sequenced a reference strain of H. marmoreus (Haemi 51,987–8). We evaluated various assembly strategies, and as a result the Allpaths and PBJelly produced the best assembly. The resulting genome was 42.7 Mbp in length and annotated with 16,627 gene models. A putative gene (Hypma_04324) encoding the antifungal and antiproliferative hypsin protein with 75% sequence identity with the previously known N-terminal sequence was identified. Carbohydrate active enzyme analysis displayed the typical feature of white-rot fungi where auxiliary activity and carbohydrate-binding modules were enriched. The genome annotation revealed four terpene synthase genes responsible for terpenoid biosynthesis. From the gene tree analysis, we identified that terpene synthase genes can be classified into six clades. Four terpene synthase genes of H. marmoreus belonged to four different groups that implies they may be involved in the synthesis of different structures of terpenes. A terpene synthase gene cluster was well-conserved in Agaricomycetes genomes, which contained known biosynthesis and regulatory genes. Conclusions: Genome sequence analysis of this mushroom led to the discovery of the hypsin gene. Comparative genome analysis revealed the conserved gene cluster for terpenoid biosynthesis in the genome. These discoveries will further our understanding of the biosynthesis of medicinal bioactive molecules in this edible mushroom. [ABSTRACT FROM AUTHOR]

[Display omitted] • THP improved the performance of AD of CM by 1.4 times compared to the control. • By applying THP, HRT can be shortened from 36 to 13.2 d without performance loss. • THP application greatly affected the microbial community. • The reactor stability decreased with shortening of HRT, and application of THP. In this study, we investigated the potential of thermal hydrolysis pretreatment (THP) to reduce the hydraulic retention times (HRTs) in the anaerobic digestion (AD) of cattle manure (CM). The AD with THP (THP AD) outperformed the control AD by over 1.4 times in terms of methane yield and volatile solid removal, even under the same HRT conditions. Remarkably, even when the THP AD was operated with an HRT of 13.2 d, it performed better than the control AD operated with an HRT of 36.0 d. In THP AD, there was a shift in the dominant archaeal genus responsible for methane generation from Methanogranum (at HRT of 36.0 – 13.2 d) to Methanosaeta (at HRT of 8.0 d). However, decreasing HRT, and applying THP resulted in reduced stability, accompanied by increased inhibitory compounds, and changes in the microbial community. Further confirmation is required to assess the long-term stability of THP AD. [ABSTRACT FROM AUTHOR]

• The hydrogen crossover data can be correlated to the ion channel morphology. • The hydrogen crossover data corroborates with the Gierke's spherical cluster model. • It was shown that the ion channels exist as discrete spherical clusters. • A two-phase Maxwell model was derived to predict the hydrogen crossover accurately. • The ion channel connectivity can be deduced using the proposed method. The morphology of ion channels within ion exchange membranes (IEM) has long been disputed by researchers. Several accepted models include the Gierke's discrete spherical cluster model, continuous parallel cylinder model, and flat-layered model. The primary experimental data to support each model were mostly small-angle X-ray spectroscopy (SAXS). In this work, we propose that hydrogen permeability (i.e. crossover) data of hydrated IEMs could provide valuable insights into understanding the ion channel connectivity and continuity within the membrane. We re-derived the two-phase Maxwell-Eucken transport models to predict the hydrogen crossover of hydrated IEMs. The model accurately predicted the hydrogen crossover of Nafion and in-house BPSH membrane series within 10% error range. The predicted results were experimentally validated using the pressure decay method (PDM) developed in our group specifically for this purpose. By comparing the degree of change in hydrogen crossover between the dry and hydrated membranes, it was possible to extract semi-qualitative information about the membrane's controversial ion-conducting channel morphology. Interestingly, our experimental data and model prediction corroborates with the Gierke's conjecture that the water phase within the ion channel exists as discrete spherical clusters, not as the continuous percolated phase (the parallel cylinder model). Although there is yet no consensus on the internal morphology of ion channels, our work suggests that hydrogen crossover data can be useful in elucidating the ion channel morphology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermal hydrolysis pretreatment significantly enhanced the BMP and energy gain of AD of cattle manure. • Refractory compounds formed at THP conditions exceeding 180 °C, and at lower temperatures with addition of NaOH greater than 2 wt%. • The THP at 160 °C without NaOH shows the highest energy gain while alleviating the formation of refractory compounds. Anaerobic digestion (AD) coupled with thermal hydrolysis pretreatment (THP) is appealing because it enhances the energy conversion rate of organic wastes. Here, cattle manure, the most abundant organic waste, was thermally hydrolyzed as a pretreatment of AD. In order to increase the process efficiency, a NaOH solution was introduced. Increasing the amount of NaOH addition during the THP enhances lignin removal and solubilization of cattle manure. The thermally hydrolyzed cattle manure (at 160 °C with 2 % (dry wt.) NaOH addition) showed a significantly higher biochemical methane potential of 227.0 ± 11.0 mL-CH 4 /g-volatile solid compared to that of intact cattle manure (182.2 ± 2.5 mL-CH 4 /g-volatile solid). Refractory compounds (humic acid-like substances and furfural) were identified at THP temperatures above 180 °C without NaOH addition, and it was enhanced by increasing NaOH addition. Energy balance analysis showed that additional 161.4 ± 39.3 MJ of energy can be gained per ton of cattle manure by applying THP (at 160 °C without NaOH addition). This study provides insights into the changes in the physicochemical and biochemical properties of cattle manure caused by alkaline THP. [ABSTRACT FROM AUTHOR]

The current work reports on the effect of annealing temperatures on the morphology and photoluminescence properties of SrAl 2 O 4 : Eu, Dy thin films on sapphire (0001) substrates fabricated by pulsed laser deposition technique. Scanning electronic microscopy and atomic force microscopy were used to investigate the thickness, surface topography, and the morphology of the films. The film deposited using a higher annealing temperature was packed with a uniform layer of larger particle size grains. In addition, the surface of this film was shown to be relatively rougher than that without annealing treatment. An intense green emission, which is attributed to the 5 d -4 f transition of Eu 2 + was observed at about 520 nm from the films with annealing treatment. The effects of annealing treatment on the morphology, topography, and photoluminescence properties are discussed in detail. [ABSTRACT FROM AUTHOR]

This paper presents characterization of 300-GHz wireless channel on a computer motherboard, where several different measurement scenarios have been considered. Results indicate that the presence of the ground plane and/or vertical parallel-plate structures in the channel introduces multipath that, if constructively superimposed, may create a path loss lower than free-space propagation path loss. In addition, it has been found that a few centimeters of vertical misalignment between the transmitter and the receiver result in a path loss greater than 5 dB. Furthermore, the results indicate that vertical components such as dual in-line memory modules with reflection coefficient close to one for all incident angles can be used to create directed non-line-of-sight (LoS) links with wide coherence bandwidth. Finally, for LoS propagation obstructed by large objects, such as a heatsink, the path-loss exponent of 1.77 is found, while the rotating fan causes periodic fading in the received power, indicating that channel equalization techniques will be needed to overcome deep fades. All these results indicate that optimal communications can be achieved by carefully positioning the antennas with respect to the motherboard layout. [ABSTRACT FROM PUBLISHER]

Here, we describe the motion of a microcantilever under water, being stirred by a rotating stir bar. Specifically, the thermomechanical fluctuations of the microcantilever are monitored as a function of the rotation frequency of the stir bar and compared with those under stationary water and in air. While the measured probability density functions both in air and stationary water show well-defined Gaussian distributions in displacement, with increasing rotation frequency of the stir bar, we note the growing tail of the probability density function as well as high level of the noise power spectral density, which can be attributed to the turbulent fluctuation within the water, caused by the motion of the stir bar. The work presented demonstrates the cantilever-based mechanical probing of the fluid motion. [ABSTRACT FROM AUTHOR]

This paper presents measurements and statistical characterization of 300- to 320-GHz desktop channels. The measurements are performed in line-of-sight (LoS) and non-LoS (NLoS) environments. From the large set of LoS measured data, the parameters for the single-slope path-loss model with shadowing are devised. The results show that the path-loss exponent is around 1.9 and that the variations due to shadowing are similar across different frequencies and different bandwidths. Furthermore, the impact of different materials on the path loss is studied in the NLoS environment. The results show that metal objects in the propagation path cause multiple strong reflections, leading to a higher path loss. Furthermore, the statistical analysis of multipath propagation is performed. The root-mean-square (RMS) delay spread, the mean excess delay, the maximum excess delay, and the coherence bandwidth for LoS and NLoS environments are calculated. The results show that the mean excess delay and RMS delay spread increase with distance and that the RMS delay spread in the desktop terahertz channel is much smaller than that in typical indoor ultrawideband channels. In addition, the power delay profiles for LoS and NLoS environments are analyzed. The results show that strong reflections from the transmitter and receiver electronics are present in both LoS and NLoS environments. Finally, the statistical analysis of the measured signal amplitude in LoS and NLoS environments is performed. For both LoS and NLoS propagation environments, it is found that the lognormal distribution provides the best fit. [ABSTRACT FROM PUBLISHER]

This paper presents measurements and characterization of D-band indoor channels. The measurements are performed in line-of-sight (LoS), obstructed-LoS (OLoS), and reflected non-LoS (RNLoS) environments. For OLoS sceanrio, cylindrical objects of different materials are used as an obstruction. For RNLoS, different surfaces are used as reflectors. From the large set of LoS and OLoS measured data, the parameters for single-slope path loss model with shadowing are devised. Furthermore, the analysis of multipath propagation is performed. The results show that strong multiple reflections from the transmitter and receiver electronics are present both in LoS and OLoS environments. Additionally, the results show that glass and ceramic objects in the propagation path produce surface-diffracted rays which clock-wise and counter clock-wise superposition leads to frequency-dependent path loss. Finally, the results show that the RNLoS measured path loss with aluminum plate as a reflector is very similar to free-space path loss when the angle of incidence and the angle of reflection are equal. [ABSTRACT FROM PUBLISHER]

ABSTRACT The first 300-GHz linearly tapered slot antenna with the average gain of 13 dBi has been designed, fabricated, and tested. To reduce the cost of testing, this article also proposes to pair relatively low-cost 300-320 GHz communication system with 10 MHz-30 GHz vector network analyzer and use the signal processing techniques. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:713-717, 2015 [ABSTRACT FROM AUTHOR]

Valorization of oil sludge has been gaining attention to improve the sustainability of the petroleum industry. This study aimed to assess the possibility of anaerobic co-digestion of oil scum and secondary sludge with food waste (or swine manure). Oil scum and secondary sludge were obtained from a wastewater treatment plant (WWTP) of a petrochemical plant. Physicochemical properties, hazardous materials, and microbial community were characterized and biochemical methane potential was performed by a simplex-lattice mixture design. More than 87% (wet wt.) of the oil scum consisted of total petroleum hydrocarbons (TPHs) (21,762 mg/L) that are difficult to be degraded by anaerobes. The secondary sludge showed low TPHs (5 mg/L) and a bacterial community similar to that of municipal WWTPs. The heavy metal (Cu, As, Cr, Ni, Mn, Zn, and V) concentrations in the oil scum and secondary sludge were similar (20–600 mg/L). The maximum methane potentials of the oil sludge and secondary sludges were 20 ± 2 and 56 ± 3 mL CH 4 /g-volatile solid, respectively. The co-digestion with food waste or swine manure led to a synergy effect on methane production of the co-digestion substrate (10–40% increase compared to the calculated value; v/v) by balancing the C/N ratio. Due to the high TPH contents, oil scum is not appropriate for co-digestion. The co-digestion of secondary sludge with food waste and/or swine manure is recommended. It is necessary to consider whether the concentration of heavy metals is at a level that inhibits the anaerobic co-digestion depending on the operating conditions such as mixing ratios and solid contents. • Oil sludges from petrochemical wastewater treatment plant were characterized. • Oil scum and secondary sludge were co-digested with food waste and swine manure. • Heavy metals in oil sludge were in inhibition level for anaerobic digestion. • The organic waste can cause synergy effect on methane potential by balancing C/N. [ABSTRACT FROM AUTHOR]

Two printed circuit board embedded global positioning system antennas with a T-shape are presented in this article.Both antennas are loaded with three lumped elements and have the same antenna and ground size. Antenna 1 is used to a chip capacitor at the input port, whereas Antenna 2 is equipped with a chip inductor. The resonant frequency decreases with increasing capacitance for Antenna 1, whereas that of Antenna 2 does not change significantly with change in the inductance. Antenna 1 has a lower bandwidth and smaller gain than Antenna 2. Both antennas are investigated via simulations and experiments. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:576-580, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27350 [ABSTRACT FROM AUTHOR]

This article presents compact global positioning system antennas loaded with a coupling strip and lumped elements for mobile phones. The first antenna proposed (Antenna 1) has a one chip capacitor, whereas the second (Antenna 2) uses both a one chip capacitor and an inductor. The size of Antenna 1 is 5 × 10 mm2, whereas Antenna 2 is 5 × 8 mm2. The radiation patterns are almost omni-directional and the measured peak gain is 0.5 dBi at 1575 MHz. Both antennas are designed and examined via simulation and experiment. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:363-366, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27317 [ABSTRACT FROM AUTHOR]

Abstract: Objective: We aimed to compare the quality of chest compressions performed by inexperienced rescuers in different positions, notably supine and at a 30° inclined lateral position, to ascertain whether high-quality chest compression is feasible on a pregnant subject in cardiac arrest. Subjects and methods: We performed a prospective, randomised crossover design study. Each participant performed 2-min chest compressions in two different positions on a mannequin: a supine position and a 30° left inclined lateral position. After 2min of chest compression in one position, the participant took a rest for 10min to minimise rescuer fatigue and then performed chest compression in the second position. Data on chest compression rate, mean chest compression depth, correct compression depth rate, correct recoil rate, and correct hand position rate were collected. To measure the angle between the rescuer''s arm and the victim''s chest surface, chest compressions were recorded with a video recorder. After each practice session, participants were asked to report the subjective difficulty of performing chest compressions using a visual analogue scale. Results: All 32 participants successfully completed the study. The mean compression rate and depth were 121.0 per minute and 53.3mm in the supine position and 118.8 per minute and 52.0mm in the inclined lateral position, respectively (p =0.978 and p =0.260, respectively). Also, there were no differences in the correct compression depth rate, the correct hand position rate, or the correct recoil rate (p =0.426, p =0.467, and p =0.260, respectively). However, the lowest and highest angles and the subjective difficulty of chest compression differed significantly (p <0.001, p <0.001, and p =0.007, respectively). Conclusions: Inexperienced rescuers appear to be capable of performing high-quality chest compressions in a 30° inclined lateral position on pregnant women in a simulated cardiac arrest state. [Copyright &y& Elsevier]

Abstract: In consciousness or anesthesia studies, pinpointing the precise moment of consciousness or anesthetic transition has been challenging because of the variable lag time between a treatment and its induced response. Here, we describe a novel behavioral method, a forced walking test, which pinpoints the moment of the anesthetic-induced loss of motion (LOM) without handling the animals manually. The mouse is forced to walk on a treadmill, and an anesthetic drug is administered into the peritoneum via a previously secured injection route. The physical activity and the angle of head posture are tracked using a motion sensor preinstalled on the animal''s head. The moments of LOM and recovery of motion (ROM) are identified from the physical activity parameters obtained by the sensor. Comparison of our method with the conventional loss-of-righting-reflex assay showed that the time point of LOM was not significantly different between the two methods when examined with two different types of anesthetic agents, propofol and ketamine/xylazine cocktail. In addition, the electrophysiological signals simultaneously acquired in the cortex and the thalamus of the mouse during the forced walking test showed that the brain rhythms induced by ketamine/xylazine anesthesia were generated and terminated in a time-locked manner with respect to LOM and ROM, respectively. In conclusion, the forced walking test allows an objective and precise detection of anesthetic-induced LOM, as well as ROM during awakening from anesthesia, in test animals. [Copyright &y& Elsevier]

Abstract: Frontoparietal connectivity has been suggested to be important in conscious processing and its interruption is thought to be one mechanism of general anesthesia. Data in animals demonstrate that feedforward processing of information may persist during the anesthetized state, while feedback processing is inhibited. We investigated the directionality and functional organization of frontoparietal connectivity in 10 human subjects anesthetized with propofol on two separate occasions. Multichannel electroencephalography and a computational method of assessing directed functional connectivity were employed. We demonstrate that directed feedback connectivity is diminished with loss of consciousness and returns with responsiveness to verbal command. We also applied the Dendrogram classification method to assess the global organization of directed functional connectivity during consciousness and anesthesia. We demonstrate a state-specific hierarchy and subject-specific subhierarchy in functional organization. These data support the hypothesis that specific states of human consciousness are defined by specific states of frontoparietal connectivity. [Copyright &y& Elsevier]

Abstract: We studied the long-term memory in diverse stock market indices and foreign exchange rates using Detrended Fluctuation Analysis (DFA). For all high-frequency market data studied, no significant long-term memory property was detected in the return series, while a strong long-term memory property was found in the volatility time series. The possible causes of the long-term memory property were investigated using the return data filtered by the AR(1) model, reflecting the short-term memory property, the GARCH(1,1) model, reflecting the volatility clustering property, and the FIGARCH model, reflecting the long-term memory property of the volatility time series. The memory effect in the AR(1) filtered return and volatility time series remained unchanged, while the long-term memory property diminished significantly in the volatility series of the GARCH(1,1) filtered data. Notably, there is no long-term memory property, when we eliminate the long-term memory property of volatility by the FIGARCH model. For all data used, although the Hurst exponents of the volatility time series changed considerably over time, those of the time series with the volatility clustering effect removed diminish significantly. Our results imply that the long-term memory property of the volatility time series can be attributed to the volatility clustering observed in the financial time series. [Copyright &y& Elsevier]

We study the emergent functional neural network organized by synaptic reorganization by the spike timing dependent synaptic plasticity (STDP). We show that small-world and scale-free functional structures organized by STDP, in the case of synaptic balance, exhibit hierarchial modularity. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the relative market efficiency in financial market data, using the approximate entropy(ApEn) method for a quantification of randomness in time series. We used the global foreign exchange market indices for 17 countries during two periods from 1984 to 1998 and from 1999 to 2004 in order to study the efficiency of various foreign exchange markets around the market crisis. We found that on average, the ApEn values for European and North American foreign exchange markets are larger than those for African and Asian ones except Japan. We also found that the ApEn for Asian markets increased significantly after the Asian currency crisis. Our results suggest that the markets with a larger liquidity such as European and North American foreign exchange markets have a higher market efficiency than those with a smaller liquidity such as the African and Asian markets except Japan. [Copyright &y& Elsevier]

A nontrivial transition from the synchronous to the nonsynchronous state of two coupled nonautonomous oscillators is studied through the theory of two coupled circle maps (torus maps). For the case of nonidentical systems, the transition occurs without the connection to the change in the sign of Lyapunov exponent. We find that the scaling exponent for the intermittent slips near the critical point, which is measured by rotation sets (fluctuations in rotation vectors), depends on the system parameters unlike the case of phase synchronization for two coupled autonomous chaotic oscillators. We demonstrate that through the model of torus maps this nontrivial transition is induced by a boundary crisis on a torus geometry and intermittent slips could be described as the chaotic transient as a result of the crisis. [Copyright &y& Elsevier]

Linear theory for phonon scattering by discrete breathers in the discrete nonlinear SchrÖdinger equation using the transfer matrix approach is presented. Transmission and reflection coefficients are obtained as a function of the wave vector of the input phonon. The occurrence of a nonzero transmission, which in fact becomes perfect for a symmetric breather, is shown to be connected with localized eigenmodes thresholds. In the weak-coupling limit, the perfect reflection is shown to exist, which requires two scattering channels. A necessary condition for a system to have a perfect reflection is also considered in a general context. [ABSTRACT FROM AUTHOR]

This letter presents a small printed PCB-embedded antenna for a mobile phone with GPS/GLONASS satellite navigation systems. The proposed antenna consists of a feeding strip, two coupling strips, and two chip capacitors. One end of each of the coupling strips is terminated with a chip capacitor and the other end is connected to the ground. The antenna measures 5 mm × 9 mm, and it is placed at the corner of the ground, which measures 40 mm × 70 mm. The bandwidth with a VSWR of 3:1 covers the GPS/GLONASS operation band. The radiation patterns are similar to those of a dipole antenna. The measured peak gain is 0.2 dBi at the GPS/GLONASS frequency. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2736-2736, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27197 [ABSTRACT FROM AUTHOR]

A method to optimise the angle reflection performance of Berenger’s perfectly matched layer (PML) absorbing boundary condition for finite-difference time-domain (FDTD) method is described. By specifying the conductivity in each of the PML sublayers, the wide-angle reflection performance can be improved. To improve the angle reflection performance as well as to reduce the discretisation error characteristic due to the FDTD approximation, a two-step conductivity profile is used in PML. To obtain the optimal value for each conductivity profile, the micro-genetic algorithm method is employed. Using this method, good wide-angle reflection performance of PML is achieved. [ABSTRACT FROM AUTHOR]

Precise control over polarity in field‐effect transistors (FETs) plays a pivotal role in the design and construction of complementary metal–oxide–semiconductor (CMOS) logic circuits. In particular, achieving such precise polarity control in 2D semiconductors is crucial for the further development of advanced electronic applications beyond unit devices. This paper presents a systematic investigation on the reversible transition of carrier types in a 2D MoTe2 semiconductor under different annealing atmospheres. Photoemission spectroscopy and density functional theory (DFT) calculations demonstrate that annealing processes in vacuum and in ambient air induce a modification in the density of states, resulting in alterations in p‐type or n‐type characteristics. These reversible changes are attributed to the physisorption and elimination of oxygen on the surface of MoTe2. Furthermore, it is found that the device geometry affects the polarity of the transistor. By strategically manipulating both the annealing conditions and the geometric configuration, the n‐ and p‐type unipolar characteristics of MoTe2 FETs are successfully modulated and ultimately demonstrating that the functionality of not only a complementary inverter with a high voltage gain of ≈20, but also more complex logic circuits of NAND and NOR gates. [ABSTRACT FROM AUTHOR]

BACKGROUND: Stopping aspirin within 1 month after implantation of a drug-eluting stent for ticagrelor monotherapy has not been exclusively evaluated for patients with acute coronary syndrome. The aim of this study was to investigate whether ticagrelor monotherapy after <1 month of dual antiplatelet therapy (DAPT) is noninferior to 12 months of ticagrelor-based DAPT for adverse cardiovascular and bleeding events in patients with acute coronary syndrome. METHODS: In this randomized, open-label, noninferiority trial, 2850 patients with acute coronary syndrome who underwent drug-eluting stent implantation at 24 centers in South Korea were randomly assigned (1:1) to receive either ticagrelor monotherapy (90 mg twice daily) after <1 month of DAPT (n=1426) or 12 months of ticagrelor-based DAPT (n=1424) between April 24, 2019, and May 31, 2022. The primary end point was the net clinical benefit as a composite of all-cause death, myocardial infarction, definite or probable stent thrombosis, stroke, and major bleeding at 1 year after the index procedure in the intention-to-treat population. Key secondary end points were the individual components of the primary end point. RESULTS: Among 2850 patients who were randomized (mean age, 61 years; 40% ST-segment–elevation myocardial infarction), 2823 (99.0%) completed the trial. Aspirin was discontinued at a median of 16 days (interquartile range, 12–25 days) in the group receiving ticagrelor monotherapy after <1 month of DAPT. The primary end point occurred in 40 patients (2.8%) in the group receiving ticagrelor monotherapy after <1-month DAPT, and in 73 patients (5.2%) in the ticagrelor-based 12-month DAPT group (hazard ratio, 0.54 [95% CI, 0.37–0.80]; P <0.001 for noninferiority; P =0.002 for superiority). This finding was consistent in the per-protocol population as a sensitivity analysis. The occurrence of major bleeding was significantly lower in the ticagrelor monotherapy after <1-month DAPT group compared with the 12-month DAPT group (1.2% versus 3.4%; hazard ratio, 0.35 [95% CI, 0.20–0.61]; P <0.001). CONCLUSIONS: This study provides evidence that stopping aspirin within 1 month for ticagrelor monotherapy is both noninferior and superior to 12-month DAPT for the 1-year composite outcome of death, myocardial infarction, stent thrombosis, stroke, and major bleeding, primarily because of a significant reduction in major bleeding, among patients with acute coronary syndrome receiving drug-eluting stent implantation. Low event rates, which may suggest enrollment of relatively non–high-risk patients, should be considered in interpreting the trial. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03797651. [ABSTRACT FROM AUTHOR]

Background: Although rhythm control could be the best for symptomatic atrial fibrillation (AF), some patients fail to achieve sinus rhythm (SR). This study aimed to identify clinical risk factors of failed electrical cardioversion (ECV). Methods: A total of 248 patients who received ECV for persistent AF or atrial flutter (AFL) were retrospectively reviewed. Patients were divided into three groups: Group 1 maintained SR for > 1 year, group 2 maintained SR ≤ 1 year after ECV, and group 3 failed ECV. SR maintenance was assessed using regular electrocardiography or Holter monitoring. Results: Patients were divided into group 1 (73, 29%), group 2 (146, 59%), and group 3 (29, 12%). The mean age of patients was 60 ± 10 years, and 197 (79%) were male. Age, sex, and baseline characteristics were similar among groups. However, increased cardiac size, digoxin use, heart failure (HF), and decreased left ventricular ejection fraction (LVEF) were more common in group 3. Univariate analysis of clinical risk factors for failed ECV was increased cardiac size [hazard ratio (HR) 2.14 (95% confidence interval [CI], 1.06–4.34, p = 0.030)], digoxin use [HR 2.66 (95% CI, 1.15–6.14), p = 0.027], HF [HR 2.60 (95% CI, 1.32–5.09), p = 0.005], LVEF < 40% [HR 3.45 (95% CI, 1.00–11.85), p = 0.038], and decreased LVEF [HR 2.49 (95% CI, 1.18–5.25), p = 0.012]. Among them, HF showed clinical significance only by multivariate analysis [HR 3.01 (95% CI, 1.13–7.99), p = 0.027]. Conclusions: Increased cardiac size, digoxin use, HF, LVEF < 40%, and decreased LVEF were related to failed ECV for persistent AF or AFL. Among these, HF was the most important risk factor. Further multi-center studies including greater number of participants are planned. [ABSTRACT FROM AUTHOR]

Schwannoma is usually benign, encapsulated spindle cell tumor which arises from schwann cells of nerve sheath, and is the most common of the neurogenic mediastinal tumors. Various imaging modalities can be applied to assess posterior mediastinal mass which is often found incidentally without symptom and frequently misdiagnosed for other benign conditions both clinically and radiologically in which clinicians should be aware of. [ABSTRACT FROM AUTHOR]

The effects of hypertension on long-term outcomes according to glycemic status in patients with acute myocardial infarction (AMI) after successful implantation of newer-generation drug-eluting stents (DES) have not been fully investigated. In this retrospective cohort study, a total of 11,911 patients were classified into 6 groups according to their glycemic status and presence or absence of hypertension. The major outcome was major adverse cardiac events (MACE), defined as all-cause death, recurrent myocardial infarction (Re-MI), or any revascularization. In patients without hypertension, the major outcomes were similar between the normoglycemia and prediabetes groups. However, MACE, all-cause death, cardiac death (CD), Re-MI rates were higher in patients with type 2 diabetes mellitus (T2DM) than in normoglycemic patients. Additionally, Re-MI was higher in patients with T2DM than in prediabetic patients. In patients with hypertension, although the major outcomes were similar between the prediabetes and T2DM groups, in both the prediabetes and T2DM groups, MACE, all-cause death, and CD rates were higher than those in the normoglycemia group. During a 2-year follow-up, the comparable harmful effects of hypertension in patients with AMI and prediabetes or T2DM were observed. Effective blood pressure and glucose control should be strengthened to reduce mortality in these patients. [ABSTRACT FROM AUTHOR]

The ultimate value of theories describing the fundamental mechanisms behind asset prices in financial systems is reflected in the capacity of such theories to understand these systems. Although the models that explain the various states of financial markets offer substantial evidence from the fields of finance, mathematics, and even physics, previous theories that attempt to address the complexities of financial markets in full have been inadequate. We propose an artificial double auction market as an agent-based model to study the origin of complex states in financial markets by characterizing important parameters with an investment strategy that can cover the dynamics of the financial market. The investment strategies of chartist traders in response to new market information should reduce market stability based on the price fluctuations of risky assets. However, fundamentalist traders strategically submit orders based on fundamental value and, thereby stabilize the market. We construct a continuous double auction market and find that the market is controlled by the proportion of chartists, Pc. We show that mimicking the real state of financial markets, which emerges in real financial systems, is given within the range Pc = 0.40 to Pc = 0.85; however, we show that mimicking the efficient market hypothesis state can be generated with values less than Pc = 0.40. In particular, we observe that mimicking a market collapse state is created with values greater than Pc = 0.85, at which point a liquidity shortage occurs, and the phase transition behavior is described at Pc = 0.85. [ABSTRACT FROM AUTHOR]

• Biodegradable cellulose membranes were fabricated using green solvents. • Derivatized cellulose with sacrificial acetate group was utilized for phase inversion. • Methyl lactate displayed desirable properties over Cyrene and PolarClean. • Cellulose membrane exhibited excellent solvent resistance in aprotic solvents. The paradigm of the polymer industry is confronting an inevitable transition from fossil-based to bio-derived sources. The membrane-based separation process, generally regarded as a sustainable technology, mostly employs fossil-based polymeric membranes. In order to become an entirely carbon–neutral technology, all of the materials and chemicals employed during membrane fabrication must be scrutinized from a sustainability perspective. In this work, we report a versatile strategy to fabricate solvent-resistant cellulose membranes using bio-derived green solvents. The thermodynamic and kinetic aspects of the membrane fabrication process were systematically investigated. It was found that well-known green solvents such as Cyrene and PolarClean were not suitable due to high dope viscosity, whereas bio-derived methyl lactate and triethyl phosphate exhibited desirable properties to yield excellent cellulose membranes. The membrane performance could be tailored from the ultrafiltration to nanofiltration range by controlling the fabrication parameters. Importantly, the thermal treatment step prior to the deacetylation reaction was necessary to improve the solute rejection profile. The cellulose membranes displayed adequate compression resistance against pressure. However, their shear resistance was insufficient compared to that of commercial membranes. Nevertheless, the prepared cellulose membranes exhibited excellent solvent resistance in strong aprotic solvents such as N -methylpyrrolidone and N,N -dimethylacetamide, potentially allowing them to enter niche membrane markets such as the organic solvent nanofiltration (OSN). [ABSTRACT FROM AUTHOR]

[Display omitted] • The impact of Fermi level pinning on energy level alignment in PbS quantum dot is examined. • UPS analyses indicate that energetic position of PbS QD's gap-state to be c.a. 4.0 eV. • The pinning factors (S) for PbS QD-EDT and PbS-TBAI are empirically determined by UPS and LEIPES. • Higher S for PbS-EDT indicate the TBAI more effectively passivates the gap-state of PbS QD. PbS quantum dots capped by ethanedithiol (PbS QD-EDT) and tetrabutylammonium iodide (PbS QD-TBAI) and supported by different substrates were examined in terms of Fermi level pinning (FLP), gap states, and electron and hole barriers (Φ e and Φ h , respectively) using ultraviolet and low-energy inverse photoemission spectroscopy. The former analysis showed that TBAI and EDT differed in their ability to induce gap-state passivation, with the corresponding energy difference determined as 4.0 eV. Two FLP regimes were identified: at substrate work function (Ф sub) < 4.0 eV, both ligands showed perfect FLP (S ≈ 0 for holes and electrons), whereas at Ф sub > 4.0 eV, the pinning strength of PbS QD-EDT (S of Ф b,h and Ф b,e = 0.19 and 0.24, respectively) exceeded that of PbS QD-TBAI (S of Ф b,h and Ф b,e = 0.53 and 0.57, respectively). Thus, the gap states were more effectively passivated in the case of PbS QD-TBAI. Our results indicate the importance of considering FLP strength when working with high-work-function substrates for the design of optimized QD-based devices. [ABSTRACT FROM AUTHOR]

Rhythm control strategies in patients with atrial fibrillation (AF) can bring many clinical benefits. However, there is still uncertainty regarding selection of the optimal rhythm control strategy for persistent AF. Chronicity, substrate alteration, and underlying bradyarrhythmias could influence the clinical outcomes. Current guidelines do not provide a distinct recommendation for electrical cardioversion (ECV) in patients with AF with a slow ventricular response (SVR). We present two cases of sudden cardiac arrest due to sustained ventricular tachycardia/fibrillation after ECV of persistent AF with SVR. [ABSTRACT FROM AUTHOR]

Recently, the study of the financial crisis has progressed to include the concept of the complex system, thereby improving the understanding of this extreme event from a neoclassical economic perspective. To determine which variables are related to the financial event caused by the 2008 US subprime crisis using temporal correlations, we investigate the diverse variables that may explain the financial system. These variables include return, volatility, trading volume and inter-trade duration data sets within the TAQ data for 27 highly capitalized individual companies listed on the KOSPI stock market. During 2008 and 2009, the Hurst exponent for the return time series over the whole period was less than 0.5, and the Hurst exponents for other variables, such as the volatility, trading volume and inter-trade duration, were greater than 0.5. Additionally, we analyze the relationships between the variation of temporal correlation and market instability based on these Hurst exponents and the degree of multifractality. We find that for the data related to trading volume, the Hurst exponents do not allow us to detect changes in market status, such as changes from normal to abnormal status, whereas other variables, including the return, volatility and weekly inter-trade duration, indicate a significant change in market status after the Lehman Brothers' bankruptcy. In addition, the multifractality and the measurement defined by subtracting the Hurst exponent of the return time series from that of the volatility time series decrease sharply after the US subprime event and recover approximately 50 days after the Lehman Brothers' collapse. Our findings suggest that the temporal features of financial quantities in the TAQ data set and the market complexity perform very well at diagnosing financial market stability. [ABSTRACT FROM AUTHOR]

The 2-year clinical outcomes according to pre-percutaneous coronary intervention (PCI) thrombolysis in myocardial infarction (TIMI) flow grade and reperfusion timing were investigated in patients with non-ST-segment elevation myocardial infarction (NSTEMI) who received newer-generation drug-eluting stents. A total of 7506 NSTEMI patients were divided into 2 groups: early (PCI ≤ 24 hours: n = 6398; pre-PCI TIMI 0/1 [n = 2729], pre-PCI TIMI 2/3 [n = 3669]) and delayed (PCI > 24 hours: n = 1108; pre-PCI TIMI 0/1 [n = 428], pre-PCI TIMI 2/3 [n = 680]) invasive groups. Major adverse cardiac events were defined as all-cause death, recurrent myocardial infarction, or any repeat revascularization. All-cause death (P = 0.005 and 0.009, respectively) and cardiac death (P =.003 and 0.046, respectively) were significantly higher in pre-PCI TIMI 0/1 patients than in pre-PCI TIMI 2/3 patients both in the early and delayed invasive groups. In pre-PCI TIMI 0/1 patients, all-cause death rate was significantly higher in the delayed group (P =.023). In pre-PCI TIMI 2/3 patients, the clinical end point was similar between the 2 groups. An early invasive strategy is preferred to a delayed invasive strategy in reducing all-cause death in patients with pre-PCI TIMI 0/1. However, in patients with pre-PCI TIMI 2/3, both treatment strategies are acceptable. [ABSTRACT FROM AUTHOR]

An effective technique of phase contrast synchrotron radiation computed tomography was established for the quantitative analysis of the microstructures in the respiratory zone of a mouse lung. Heitzman’s method was adopted for the whole-lung sample preparation, and Canny’s edge detector was used for locating the air-tissue boundaries. This technique revealed detailed morphology of the respiratory zone components, including terminal bronchioles and alveolar sacs, with sufficiently high resolution of 1.74 µm isotropic voxel size. The technique enabled visual inspection of the respiratory zone components and comprehension of their relative positions in three dimensions. To check the method’s feasibility for quantitative imaging, morphological parameters such as diameter, surface area and volume were measured and analyzed for sixteen randomly selected terminal branching units, each consisting of a terminal bronchiole and a pair of succeeding alveolar sacs. The four types of asymmetry ratios concerning alveolar sac mouth diameter, alveolar sac surface area, and alveolar sac volume are measured. This is the first ever finding of the asymmetry ratio for the terminal bronchioles and alveolar sacs, and it is noteworthy that an appreciable degree of branching asymmetry was observed among the alveolar sacs at the terminal end of the airway tree, despite the number of samples was small yet. The series of efficient techniques developed and confirmed in this study, from sample preparation to quantification, is expected to contribute to a wider and exacter application of phase contrast synchrotron radiation computed tomography to a variety of studies. [ABSTRACT FROM AUTHOR]

In this letter, a printed planar inverted-F antenna is proposed for a quad-band operation.The proposed quasi-rectangular loop configuration yields the first and second resonant frequencies at 900 and 1800 MHz, respectively. The additional shorted strip on the bottom can expand the bandwidth at the upper band. The proposed antenna area is 8 × 38 mm2 and the ground size is 72 × 40 mm2. The measured impedance bandwidth, determined by 3:1 VSWR, has fully covered the GSM900 (880-960 MHz), DCS (1710-1880 MHz), PCS (1850-1990 MHz), and UMTS (1920-2170 MHz) frequency bands. The measured gain is higher than −1 dBi over the entire quad-band. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2337-2341, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27099 [ABSTRACT FROM AUTHOR]

Abstract: We have studied the long-term memory effects of the Korean agricultural market using the detrended fluctuation analysis (DFA) method. In general, the return time series of various financial data, including stock indices, foreign exchange rates, and commodity prices, are uncorrelated in time, while the volatility time series are strongly correlated. However, we found that the return time series of Korean agricultural commodity prices are anti-correlated in time, while the volatility time series are correlated. The -point correlations of time series were also examined, and it was found that a multifractal structure exists in Korean agricultural market prices. [Copyright &y& Elsevier]

Abstract: The cognitive unbinding paradigm suggests that the synthesis of neural information is attenuated by general anesthesia. Here, we analyzed the functional organization of brain activities in the conscious and anesthetized states, based on functional segregation and integration. Electroencephalography (EEG) recordings were obtained from 14 subjects undergoing induction of general anesthesia with propofol. We quantified changes in mean information integration capacity in each band of the EEG. After induction with propofol, mean information integration capacity was reduced most prominently in the γ band of the EEG (p =.0001). Furthermore, we demonstrate that loss of consciousness is reflected by the breakdown of the spatiotemporal organization of γ waves. We conclude that induction of general anesthesia with propofol reduces the capacity for information integration in the brain. These data directly support the information integration theory of consciousness and the cognitive unbinding paradigm of general anesthesia. [Copyright &y& Elsevier]

Abstract: The stock market has been known to form homogeneous stock groups with a higher correlation among different stocks according to common economic factors that influence individual stocks. We investigate the role of common economic factors in the market in the formation of stock networks, using the arbitrage pricing model reflecting essential properties of common economic factors. We find that the degree of consistency between real and model stock networks increases as additional common economic factors are incorporated into our model. Furthermore, we find that individual stocks with a large number of links to other stocks in a network are more highly correlated with common economic factors than those with a small number of links. This suggests that common economic factors in the stock market can be understood in terms of deterministic factors. [Copyright &y& Elsevier]