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Since 2020, synchrotron radiation facilities in several Asia-Pacific countries have been collaborating in a major project called "SYNAPSE"(Synchrotrons for Neuroscience: an Asia-Pacific Scientific Enterprise). They use x-ray imaging to attack in a coordinated fashion one of the major issues in modern science: the structure of animal and human brains, including neurons and connections. The objective is to develop Google-like maps also including detailed structural and functional information for selected regions of interest. The sheer mass of data needed for the objective poses huge problems for the acquisition, processing, storage and use of images. In order to complete the task within a reasonable time, the key element of the SYNAPSE strategy is the parallel and coordinated work of several facilities on the same specimens. This article reviews different aspects of the enterprise, including the foundations of synchrotron radiation, coherence and of its role in advanced imaging, electron accelerators, x-ray optics and detectors. This will provide the foundation for an extensive presentation of the different components of SYNAPSE, with an overview of results already obtained within the consortium.

GaN nanorod (GNR)-integrated photonic emitters (GIPEs) with horizontally self-arrayed GNRs were fabricated for the next generation displays. The self-array performance of GNRs was enhanced by the effective electric-field area.

Data of the outcomes of ventricular septal defect (VSD) closure in adults are limited to establish recommendations. Therefore, we reviewed our experience with surgical VSD closure in adult patients. We retrospectively reviewed 152 patients who underwent surgical VSD closure between January 1996 and April 2020. The median age of the patients was 30.5 [interquartile range (IQR) 23.1-42.7] years. The median follow-up duration was 10.9 (IQR 4.8-16.1) years. VSDs were classified according to the Society of Thoracic Surgeons classification as type 2 (n = 66, 43.4%), type 1 (n = 59, 38.8%), and type 4 (n = 27, 17.8%). Aortic cusp prolapse (n = 86, 56.6%) and aortic valve regurgitation (AR, n = 75, 49.3%) were the most common indications for surgical closure. Four patients underwent late reoperation (2.6%) due to AR, infective endocarditis and residual VSD. In the log-rank test, preoperative trivial or more degree of AR (P = 0.004) and coronary cusp deformity (P = 0.031) was associated with late moderate or greater degree of AR. Preoperative moderate or greater AR was associated with reoperation (P = 0.047). Only concomitant aortic valve (AV) repair at the time of VSD closure was a significant risk factor for late significant AR progression in the multivariable analysis. VSD closure in adults can be performed with low mortality and morbidity rates. AR can progress after VSD closure because the aortic cusp may have irreversible damage from long-standing shunt flow exposure. We conclude that VSD with AV deformity or AR in adults should be treated aggressively before disease progression with irreversible damage occurs.

The most promising approach for improving the electrical performance of connectors used in semiconductor test sockets involves increasing their electrical conductivity by incorporating one-dimensional (1D) conductive materials between zero-dimensional (0D) conductive materials. In this study, FeCo nanowires were synthesized by electroplating to prepare a material in which 1D materials could be magnetically aligned. Moreover, the nanowires were coated with highly conductive Au. The magnetization per unit mass of the synthesized FeCo and FeCo@Au nanowires was 167.2 and 13.9 emu/g, respectively. The electrical performance of rubber-based semiconductor connectors before and after the introduction of synthetic nanowires was compared, and it was found that the resistance decreased by 14%. The findings reported herein can be exploited to improve the conductivity of rubber-type semiconductor connectors, thereby facilitating the development of connectors using 0D and 1D materials.

Although oil-water separation technology via wettability-controlled membranes has emerged as a promising technology to treat oily wastewater, membrane fouling by faulents such as sludge flocs and colloids, and the consequent clogging of pores, severely degrades the efficiency of filtration systems. One of the main promotors of fouling by faulents is oil fouling, which is also a form of fouling itself. Despite considerable practical and academic interest in the analysis of oil-fouled membranes, direct visualization of the entire process of oil infiltration into hydrophilic membranes is still preliminary owing to (i) the similar optical contrast and physical density between oil and water, (ii) the low penetration depth of imaging methods, and (iii) the lack of 3D segmentation capability. In this study, microcomputed X-ray tomography using tunable synchrotron radiation provided direct high-speed 3D visualization of the microscale dynamics of the oil infiltration of a prewetted hydrophilic filter membrane over time. Direct visualization of the interfacial dynamics of oil infiltration opens a window into the complex liquid (water/oil)-gas-solid interface and thus helps furnish an in-depth understanding of oil fouling in the prewetted membrane.

Atrioventricular valve regurgitation (AVVR) is associated with increased morbidity and mortality in patients with single ventricle physiology. The purpose of this study was to evaluate the long-term results of the surgical management of AVVR and to analyze the effects of AV valve replacement. The medical records of 38 single ventricle patients who underwent atrioventricular valve surgery more than once between January 2001 and March 2018 were retrospectively reviewed. We analyzed and compared clinical data of patients who underwent valve replacement as an initial treatment (n = 8) for AVVR with patients who initially underwent valve repair (n = 30). The median follow-up duration was 98.1 months (range, 0.9–209.6 months). There was one early mortality and seven late mortalities. Freedom from reoperation between the two groups at 15 years of follow-up was significantly different: 18.3% in the repair group and 100% in the replacement group (p = 0.013). The replacement group showed a better overall survival rate (100%) at 15 years than the repair group (68.5%) without statistical significance (p = 0.097). All mortalities occurred in the repair group. Nine patients in the repair group (30%) and one patient in the replacement group (12.5%) showed preoperative ventricular dysfunction. RV-type single ventricle with atrioventricular (AV) valve annular dilatation was found out as a risk factor of AVV replacement both in univariate (p = 0.04) and multivariate (p = 0.004) analysis. AV valve replacement might be considered as a primary treatment option for patients who have an annular dilation with an RV-type single ventricle rather than repeated valvuloplasty.

Tillandsia usneoides in epiphytic bromeliads takes up water through the absorptive trichomes on the shoot surface under extreme environmental conditions. Although previous studies revealed the way by which T. usneoides absorbs water and prevents water loss, T. usneoides' water transport is still unclear. We characterized structures of trichome wings of T. usneoides. Wing length-to-thickness ratio with 136 and the trichome interval (d)-to-wing length (l) ratio (d/l) smaller than 1 caused the water film to flatten the wings sequentially, resulting the domino-like water transport. A hinge-like linkage between wing and outer ring cells and the wing size longer than the elastocapillary length (LEC ) brought about this unique reconfiguration, which is the flattening and recovery of wings. T. usneoides transported water rapidly on the surface as the water film propagated on the exterior trichomes with flexible wings and the transport distance at the macroscopic scale grew as tx with x = 0.68 ± 0.04, unlike the conventional scaling of t0.5 . Empirical and theoretical investigations proved our assumption that external water transport with the domino-like effect predominated over internal vascular transport. Biomimetic trichome wings simulated the domino-like water transport, highlighting the important role of flexibility wing arrays.

OBJECTIVES This study was conducted to measure suture tie-down forces and evaluate cyclic contractile forces (CCFs) in beating hearts after undersized 3-dimensional (3D) rigid-ring tricuspid valve annuloplasty (TAP). METHODS Eight force transducers were attached to the 3D rigid TAP ring. Segments 1 to 8 were attached from the mid-septal to anterior-septal commissural area in a counterclockwise order. Two-sizes-down ring TAPs were performed in 6 sheep. Tie-down forces and CCF were recorded and analysed at the 8 annular segments and at 3 levels of peak right ventricular pressure (RVP: 30, 50 and 70 mmHg). RESULTS The overall average tie-down forces and CCF were 4.34 ± 2.26 newtons (N) and 0.23 ± 0.09 N, respectively. The CCF at an RVP of 30 mmHg were higher at 3 commissural areas (segments 3, 5 and 8) than at the other segments. The increases in the CCF following changes in the RVP were statistically significant only at the 3 commissural areas (P = 0.012). However, mean CCFs remained low at all annular positions (ranges of average CCF = 0.06–0.46 N). CONCLUSIONS The risk of suture dehiscence after down-sized 3D rigid-ring TAP might be minimal because the absolute forces remained low in all annular positions even in the condition of high RVP. However, careful suturing in the septal annular area and commissures is necessary to prevent an annular tear during a down-sized 3D rigid-ring TAP.

We constructed a high-speed X-ray projection microscope at beamline 9D of the Pohang Light Source-II (PLS-II). The microscope was able to take X-ray projection micrographs with a submil-lisecond exposure time by using whitebeam X-rays from the PLS-II bending-magnet synchrotron radiation. It also takes advantage of edge enhancement in phase-contrast imaging, which significantly improves the visibility of soft materials and microfluids. Using the microscope, we captured the spreading of a water droplet on a hydrophilic and oleophilic nonwoven membrane at 1,264 frames per second. The computed tomography (CT), which visualized a three-dimensional wooden structure at a spatial resolution of 2.7 µm, took 2.5 s for scanning.

Ebstein anomaly is a rare congenital heart malformation typically involving the tricuspid valve and the right ventricle that has a wide range of anatomical and pathophysiological presentations. Various surgical repair techniques for Ebstein anomaly have been report-ed because of its near-infinite anatomical variability. Cone repair for Ebstein anomaly can achieve nearly anatomical reconstruction of the tricuspid valve with promising outcomes. In this article, the surgical techniques for cone repair in adult patients with Ebstein anom-aly are described in detail, and clinical experiences and technically challenging cases are presented.

Although the clinical outcomes of truncus arteriosus (TA) repair have been improving, few data are available on long-term outcomes after truncus arteriosus repair in the current era. This study evaluated long-term outcome after repair of TA. Fifty-one patients underwent total correction from April 1982 to June 2018. Since 2003, perioperative strategy has changed to minimal priming volume, modified ultrafiltration, and early total repair (n = 26). Mortality and reoperation rates were analyzed before and after 2003. There were 8 hospital deaths after initial operation, all before 1997. During the mean follow-up of 9.8 years, there were 2 deaths. The Kaplan-Meier estimate of survival among all hospital survivors was 94.7% at 5 years and 88.0% at 20 years. A significant independent risk factor for early mortality was operation before 2003 (Hazard ratio (HR) 9.710, p = 0.041) and REV operation (HR 8.000, p = 0.028). Freedom from reoperation for conduit change and TV repair were 88.3% and 41% at 1 and 5 years, and 96.2% and 85.4% at 1 and 5 years, respectively. After 2003, younger age and conduit choice were risk factors for conduit-related reoperation. Initial preoperative TV regurgitation was independent risk factor for sequential TV repair. Patients with TA can undergo total repair of TA with excellent results, especially in current era. Most of the patients require conduit-related reoperations. Younger age and the methods of RVOT reconstruction were risk factors for conduit-related reoperations. TV repair is necessary in limited patients, and initial regurgitation was a risk factor.

The addition of Cu becomes essential in polycrystalline n-type Bi2(Te,Se)3-based alloys since it is known to enhance stability of carrier transport properties as well as thermoelectric performance. However, a way to further optimize is necessary owing to the limited controllability of transport parameters by Cu addition. Herein, we present improved carrier transport properties via I-doping in Cu0.008Bi2Te2.7Se0.3. Weighted mobility and effective mass are increased simultaneously by small amount doping of I at Te/Se-site. As a result, ~15% increased power factor and high average thermoelectric figure of merit (zT) of 0.79 were obtained in a wide temperature range.

Though ventricular assist devices (VADs) are an important treatment option for acute heart failure, an extracorporeal membrane oxygenator (ECMO) is usually used in pediatric patients for several reasons. However, a temporary centrifugal pump-based Bi-VAD might have clinical advantages versus ECMO or implantable VADs. From January 2000 to July 2018, we retrospectively reviewed 36 pediatric patients who required mechanical circulatory support (MCS) for acute heart failure. Cases with postoperative MCS were excluded. Since 2016, we have tried to immediately add a right VAD rather than ECMO, when the patients begin to present features of right heart failure after left VAD support started in cases that the patients’ respiratory function did not require an oxygenator. Original diagnoses included dilated cardiomyopathy (n = 18), myocarditis (n = 11), and others (n = 7). Eleven patients were supported by Bi-VAD, and 25 patients were supported by ECMO; of these. Four patients were successfully weaned from VAD, and 10 patients were weaned from ECMO. Eleven patients underwent heart transplantation. Overall, we have 15 (41.7%) early mortalities. There were no significant differences in early mortality, morbidity, and weaning rate between the Bi-VAD group and the ECMO group. During the support, patients with Bi-VADs significantly required fewer platelets and showed less hemolysis than ECMO patients. Patients with myocarditis were successfully weaned from Bi-VAD support and bridged to transplantation thereafter. A temporary centrifugal pump-based Bi-VAD was clinically comparable to ECMO for pediatric patients with acceptable pulmonary function.

Synchrotron radiation transmission X-ray microscopy (SRTXM) was applied for visualization of the interfacial layer in bonded wafer pairs. The X-ray energy of 6.54 keV with a monitoring window was utilized to enhance a resolution of transmission X-ray microscopy (TXM). The monitoring window was designed a locally uncovered area of the bonded wafer pairs to make the thickness of bonded wafers less than 200 μm. The experimental results showed that the technique has sub-micron meter resolution. Also this technique can improve the resolution of the synchrotron X-ray for nanoelectronics application.

Mapping the large neural networks of animal and human brains is a fundamental but so far elusive task, because of the massive amount of data and the consequent prohibitively long image taking and processing times. We developed an effective strategy called “AXON” (Accelerated X-ray Observation of Neurons) to solve this problem. AXON can achieve comprehensive whole-brain mapping within a reasonable time by combining fast image taking and processing, plus two other critical performances: three-dimensional (3D) imaging with high and isotropic spatial resolution, and multi-scale resolution. We successfully tested this strategy with coordinated experiments at four synchrotron facilities in Japan, Taiwan, Singapore and Korea on two animal models, Drosophila and mouse. Its performances notably allowed full 3D mapping of the Drosophila brain in a few days. With reasonable improvements, AXON can deliver full mapping of large animal and human brains on a realistic time scale of a few years.

Nanoparticles in thermoelectric alloys has been considered as one of the most important ingredients to enhance their thermoelectric figure of merit zT mainly by reducing the lattice thermal conductivity due to intensified phonon scattering. However, the scattering mechanism of phonon with respect to wavelengths, which provides the comprehensive design rules for nanocomposites with enhanced zT, has not been fully understood. Here, we report a critical role of nanoparticles for the lattice thermal conductivity reduction from the theoretical and experimental analysis of the temperature-dependent thermal and electronic transport properties of p-type Ag/Cu nanoparticles-embedded Bi0.5Sb1.5Te3 with respect to their electronic, bipolar, and lattice thermal conductivities. It was found that the introduction of the Ag/Cu nanoparticles reduced the lattice thermal conductivity through the additional phonon scattering based on the changeover between the Rayleigh and geometrical scatterings, indicating the indispensability of nanoparticles to scatter phonons that cannot be scattered effectively by either point defects or grain boundaries.

Understanding the dynamics of immiscible fluid in a porous media is critical in many chemical and environmental engineering processes. However, the geological heterogeneity effect on multiphase flow behavior remains unclear. Here, the dynamics of immiscible fluid displacement and entrapment were experimentally demonstrated at pore-level using time-lapse synchrotron X-ray microtomography. A drainage-imbibition experiment was designed using an unconsolidated layered sand pack that comprised coarse sand and fine sand zones. There were significant differences between the two zones, with regard to the temporal variations in fluid saturation and morphological evolution of nonwetting fluid (oil) during imbibition. Highly connected oil clusters in the coarse zone broke up into many small fragments, whereas the cluster in the fine zone remained connected while spanning multiple pores. To further understand the impacts of pore size and connectivity on multiphase fluid dynamics, a new approach that tracks the temporal variation of immiscible fluid in individual pores was conducted. The surface area at the oil-water interface increased during imbibition, which is expected to facilitate mass transfer and surface interactions. Understanding immiscible fluid displacement in layered porous media at the pore-level could lead to more effective environmental remediation.

Contamination of vegetables due to the foliar uptake of atmospheric toxic elements could pose severe health risks. However, the uptake mechanisms of potencially toxic elements (PTEs) from the atmosphere and translocation by plant leaves remain unclear. In this study, carboxylic acid-functionalized water-soluble CdSe/ZnS quantum dot nanoparticles (QD NPs) were used as an experimental particle model of PTEs in the edible plant garlic chive (Allium tuberosum). A droplet of QD NP suspension was deposited to simulate the conditions of raindrops containing metal particles falling on a plant leaf. The 3D spatial distribution of QD NPs in plant leaves was measured using three complementary imaging techniques: synchrotron X-ray microcomputed tomography (micro-CT), nano-CT, and two-photon microscopy (TPM). The TPM and micro-CT results revealed that QD NPs deposited on garlic chive leaves penetrated the plant leaves. Nano-CT images showed that QD NPs are absorbed into mesophyll cells and phloem vessels. The results of TEM and TPM imaging demonstrated that QD NPs penetrate through the leaves and translocate in the direction of the stem. The use of these emerging imaging techniques improved the ability to detect and visualize NPs in a plant leaf. These observations also provide mechanistic insights into foliar metal uptake and their translocation and accumulation.

(Bi,Sb)2Se3 alloys are promising alternatives to commercial n-type Bi2(Te,Se)3 ingots for low-mid temperature thermoelectric power generation due to their high thermoelectric conversion efficiency at elevated temperatures. Herein, we report the enhanced high-temperature thermoelectric performance of the polycrystalline Cl-doped Bi2−xSbxSe3 (x = 0.8, 1.0) bulks and their sustainable thermal stability. Significant role of Cl substitution, characterized to enhance the power factor and reduce the thermal conductivity synergetically, is clearly elucidated. Cl-doping at Se-site of both Bi1.2Sb0.8Se3 and BiSbSe3 results in a high power factor by carrier generation and Hall mobility improvement while maintaining converged electronic band valleys. Furthermore, point defect phonon scattering originated from mass fluctuations formed at Cl-substituted Se-sites reduces the lattice thermal conductivity. Most importantly, spark plasma sintered Cl-doped Bi2−xSbxSe3 bulks are thermally stable up to 700 K, and show a reproducible maximum thermoelectric figure of merit, zT, of 0.68 at 700 K.

We examined the functional morphology of loach Misgurnus anguillicaudatus skin by using synchrotron X-ray micro-computed tomography (SR-μCT) and high-contrast staining using osmium tetroxide or phosphotungstic acid (PTA), which enhances the image contrast of soft tissues. The captured high-spatial resolution images revealed that the surface ornamentations were stuck in the basement membrane of the loach scales. The ornamentations consisting of grooves (radii) and ridges (circuli) that can move freely and bend flexibly. The cross-sectional lateral microstructures of flat, concave and convex loach skins were observed from a live image of loach skin obtained through dark-field optical coherence tomography (OCT) imaging. The thickness of loach skin was changed with varying empty space between the mucous-cell layer and the scales by bending motion of loach. In addition, through direct measurement of drag reduction of loach skin, the mucous layer was found to have a strong influence on the reduction of skin friction. The present results enhance the understanding of the functional morphologies of mucous layer of loach to secrete mucus for skin friction reduction.

Two configurations of single-walled carbon nanotube-based chemi-capacitive gas sensors were fabricated, i.e., horizontal and vertical. Further, their sensing properties for hexane and ammonia (NH3) vapor were characterized and compared with chemi-resistive-type sensing properties. Upon exposure to hexane and NH3 vapor, both capacitance and resistance varied as the analyte concentration increased. The sensing sensitivity measured along the horizontal direction increased with the device resistance. However, the capacitive sensing response along the vertical direction was independent of the number and fraction of semi-conductive single-walled carbon nanotubes. Furthermore, the vertical chemi-capacitive sensing response was dependent on the dipole moment of analytes.

A three-dimensional thermoelectric (TE) nanocomposite based on functionalized single-walled carbon nanotubes (f-SWCNTs), tellurium nanowires (Te NWs), and polymethyl methacrylate (PMMA) microbeads was fabricated by a hot compaction via solvent casting. We chose a minimum content of f-SWCNTs of 1 wt% for fabricating the nanocomposite based on percolation threshold. The nanocomposite containing 2 wt% f-SWCNTs and 48 wt% Te NWs exhibited an electrical conductivity of 0.93 S/cm, a Seebeck coefficient of 303 μV/K, a thermal conductivity of 0.23 W/mK and a figure-of-merit (ZT) of 0.01 at RT. The electrical conductivity of the nanocomposite were higher than that of the Te NW/PMMA nanocomposite. In contrast, the thermal conductivity value showed a trend opposite to that of the electrical conductivity. This is because the f-SWCNTs formed bridges between the Te NWs into the nanocomposite, resulting in heterostructured interfaces. We believe that this-type nanocomposite can be widely used for thermoelectric generators at low temperature.

Herein, we report the enhanced thermoelectric performance of Cu incorporated Bi2Te2.7Se0.3 prepared by melt spinning. The electronic transport properties were significantly improved by Cu incorporation due to the synergetic effect of carrier tuning, band modification, and electron-phonon transport control. The steady dimensionless thermoelectric figure of merit higher than 0.90 was achieved in the wide range of temperature range of 350–450 K for Cu0.008Bi2Te2.7Se0.3, which is ~30% enhancement in comparison with pristine Bi2Te2.7Se0.3. This result can lead to high thermoelectric power generation efficiency 4.2% at ΔT = 180 K.

Rare-earth-based core-shell spring nanomagnets have been intensively studied in the permanent magnet industry. However, the inherent agglomeration characteristics of zero-dimensional (0-D) magnetic nanoparticles are an issue in practical fabrication of magnetic nanocomposites due to deterioration in exchange-coupling interactions, resulting in inferior magnetic performance. Here, with an aim to overcome the structural limitations, we report a new type of SmCo/FeCo core-shell nanomagnet with a well-dispersed one-dimensional (1-D) structure prepared by a combination of electrospinning and electroless plating processes. An FeCo layer with a tailored thickness on nanoscale SmCo was produced to achieve a sufficient exchange-coupling effect. The influence of electroless plating time on the microstructure of fibers was discussed, and comparisons were made as a function of the magnet shape. A 1-D SmCo/FeCo spring nanomagnet having a core diameter ranging from 150 to 200 nm and a shell thickness of 15-20 nm showed a potent exchange-coupling effect compared with its 0-D counterpart. This effectively reduced self-aggregation and further showed a remarkable enhancement in (BH)max (above 45.7%). We think that this novel structure marks a new era in the exchange-spring magnet industry and may overcome the limitations of traditional core-shell nanomagnets.

Controllable crystal orientation is necessary to obtain high thermoelectric performance in thin films of Bi2Te3 alloys. In the present study, highly (110)-oriented thin films of n-type Bi2Te3-xSex with improved composition controllability are prepared through a simple electrodeposition-based process. Using potential-current co-adjusted pulse electrodeposition (PCP-ED) with adjustments to the zero current during the off-time period enables the fabrication of dense Bi2Te3-xSex thin films with highly (110)-oriented grains by minimizing the ionic gradient (Bi3+, Te2−, Se2−) between the substrate and solution. The power factor of the PCP-ED thin film was much higher than that of the dendritic Bi2Te3-xSex thin film fabricated by constant-potentiostatic electrodeposition (C-ED) because of the simultaneous enhancement of electrical conductivity and Seebeck coefficient. The high power factor of ∼1920 μW/m⋅K2, which is the best value among reported n-type Bi2Te3-based thin films, was obtained at room temperature after low-temperature annealing at 200 °C by exploiting the crystallinity enhancement and carrier concentration optimization.

The Talbot effect is used in novel contrast imaging techniques that measure X-ray refractions and scattering. We examined formation of periodic fringes by the Talbot effect at beamline 6C Bio Medical Imaging of the Pohang Light Source-II, a facility for synchrotron radiation X-ray imaging. Talbot fringes were not observable under a normal illumination condition at the beamline, but appeared when we made a narrow opening of a slit next to the synchrotron radiation source that should have improved the transverse coherency of the beam. The Talbot fringes were identified by comparison with a numerical simulation, and also measuring the fringe visibility at fractional Talbot distances using grating interferometry.