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Synchrotron radiation microcomputed tomography (SR‐μCT) can provide non‐destructive three‐dimensional investigation for soft tissue with high resolution. The aim of this study is to evaluate technical improvements in microcomputed tomographic imaging of human lung tissue using a synchrotron radiation source at the 6C biomedical beamline. SR‐μCT images of excised human lung tissue (6 mm vertically and 10 mm horizontally sized) were explored at the 6C biomedical beamline in the Pohang accelerator laboratory (Pohang, Republic of Korea) using phase retrieval methods with a modified Bronnikov algorithm. Experimental data collection was performed with changes in the following conditions: the presence of a graphite attenuator, sample to detector distance, the presence of different scintillators and increasing pixel sizes. We identified that the resolution of lung tissue images was sufficiently enhanced when the graphite attenuator was not applied, 550 mm of sample to detector distance, with Cadmium tungsten (CdWO4) scintillator and twice binning of the pixel data and could be comparable with images from pathologic examination. Refinement of SR‐μCT techniques for soft tissue originating from the human body would advance the potential clinical application of synchrotron radiation in the near future. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The tree frog is a prominent amphibian among terrestrial vertebrates known for its ability to adhere to various surfaces through the capillary forces of water in the microchannels between micropillars on its disc‐shaped toe pads, a phenomenon known as wet adhesion. However, the secretion pattern of mucus on the attachment surface of living tree frog toe pads and the distribution of active mucus pores (AMPs) have not yet been fully elucidated. In this study, we utilized synchrotron X‐ray micro‐computed tomography and interference reflection microscopy to obtain the spatial distribution of the entire population of ventral mucus glands on the toe pads of living tree frogs and the real‐time mucus secretion patterns from the ventral mucus pores on the contact surface under different environmental conditions. We observed that the number and secretion frequency of AMPs on the toe pad are regulated according to environmental conditions. Such dynamic mucus secretion on the tree frog's toe pad could contribute to the understanding of capillary force regulation for wet adhesion and the development of adhesive surfaces by mimicking the mucus‐secreting toe pad. [ABSTRACT FROM AUTHOR]

This study introduces the synthesis of a hybrid thermoelectric material with enhanced conductivity and a high Seebeck coefficient, leveraging the properties of Te nanowires (NWs) and the conductive polymer PEDOT:PSS. Te NWs were synthesized using the galvanic displacement reaction. To further enhance conductivity, Ag-Te NWs were synthesized under optimized conditions via the Ag topotactic reaction, achieving desired results within 7 min using ethylene glycol and AgNO3. This hybrid material exhibited an electrical conductivity of 463 S/cm, a Seebeck coefficient of 69.5 μV/K at 300 K, and a power factor of 260 μW/mK2. These metrics surpassed those of conventional Te/PEDOT:PSS hybrids by a factor of 3.6, highlighting the superior performance of our approach. This study represents a significant advancement in thermoelectric materials, improving both conductivity and efficiency. [ABSTRACT FROM AUTHOR]

This study introduces the synthesis of a hybrid thermoelectric material with enhanced conductivity and a high Seebeck coefficient, leveraging the properties of Te nanowires (NWs) and the conductive polymer PEDOT:PSS. Te NWs were synthesized using the galvanic displacement reaction. To further enhance conductivity, Ag-Te NWs were synthesized under optimized conditions via the Ag topotactic reaction, achieving desired results within 7 min using ethylene glycol and AgNO3. This hybrid material exhibited an electrical conductivity of 463 S/cm, a Seebeck coefficient of 69.5 μV/K at 300 K, and a power factor of 260 μW/mK2. These metrics surpassed those of conventional Te/PEDOT:PSS hybrids by a factor of 3.6, highlighting the superior performance of our approach. This study represents a significant advancement in thermoelectric materials, improving both conductivity and efficiency. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide Open in new tab Download slide 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract We examined the use of cerium-doped gadolinium aluminum gallium garnet (GAGG:Ce) as a material for scintillation screens in synchrotron X-ray radiography (SXR). Highlighted for gamma-ray detection, GAGG:Ce is also an attractive material for SXR because of its high X-ray stopping power and the high light yield at around 530 nm. A thin and transparent screen prepared from our grown ingot of GAGG:Ce was compared with commonly used scintillators of CdWO 4 and YAG:Ce in terms of image quality under monochromatic X-ray illumination. Micron spatial resolutions were achieved with comparable image quality, suggesting that a single crystal of GAGG:Ce is competent scintillation material for SXR. Highlights • Micron-spatial resolutions are achievable using GAGG:Ce single crystal scintillation. • Visibility was compared with other commonly used scintillator screens. • GAGG:Ce was also competent in synchrotron X-ray micro computed tomography. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mono-capillary optics have been applied to increase the performance of X-ray instruments. However, performance of a mono-capillary optic strongly depends on the shape accuracy, which is determined by the diameters of the inner hollow of the capillary along the axial direction. OBJECTIVE: To precisely determine the inner diameter of the capillary optic used in X-ray imaging technique, which aims to replace the conventional method using a visible microscope. METHODS: High spatial resolution X-ray images of the mono-capillary optic were obtained by a synchrotron radiation beamline. The inner diameter of the mono-capillary optic was measured and analyzed by the pixel values of the X-ray image. RESULT: Edge enhancement effect was quite useful in determining the inner diameter, and the accuracy of the diameter determination was less than 1.32 μm. Many images obtained by scanning the mono-capillary optic along the axial direction were combined, and the axial profile, consisting of diameters along the axial direction, was obtained from the combined image. The X-ray imaging method could provide an accurate measurement with slope error of±19 μrad. CONCLUSIONS: Applying X-ray imaging technique to determine the inner diameter of a mono-capillary optic can contribute to increasing fabrication accuracy of the mono-capillary optic through a feedback process between the fabrication and measurement of its diameter. [ABSTRACT FROM AUTHOR]

Bi x Sb 2-x Te y films with controlled compositions were synthesized by a simple and cost-effective electrodeposition technique followed by post-annealing, for thermoelectric applications. Tailoring the chemical composition of ternary Bi x Sb 2-x Te y materials is critical to adjust the carrier concentration and carrier type, which are crucial to determine their thermoelectric performance. Herein, the composition of electrodeposited Bi x Sb 2-x Te y film was simply tailored by controlling the [Sb]/[Bi] ratio in the electrolytes while maintaining their dense and uniform morphology. Crystallographic properties of the Bi x Sb 2-x Te y films, such as crystallinity and grain size changes, were confirmed by X-ray diffraction. Room-temperature measurements of electrical conductivity, Hall mobility, and carrier concentration revealed that the substitution of Bi with Sb decreased the carrier concentration, and increased the mobility. The Seebeck coefficient of the ternary Bi x Sb 2-x Te y films transitioned between p- and n-type characteristics with an increase in the Bi content. Moreover, the mobility-dependent electrical conductivity of the Bi 10 Sb 30 Te 60 film resulted in a high Seebeck coefficient owing to decreased carrier concentration of the film, leading to a power factor (PF) of ∼490 μW/m K 2 . This is more than 10 times higher than the PF values of binary nanocrystalline Sb 2 Te 3 films. [ABSTRACT FROM AUTHOR]

Solar-driven water splitting with silicon photoelectrodes exhibiting high solar-to-fuel conversion efficiency is a promising way for producing hydrogen fuel in the future. In this study, a heterojunction photoanode was fabricated by the deposition of a thin indium tin oxide (ITO) layer on n-type silicon/native SiO x . A NiCl 2 -containing precursor was sprayed on the top of the photoanode, affording a NiO-Cl-OH catalyst; this NiO-Cl-OH catalyst was then activated to form an amorphous and porous NiOOH (a-NiOOH) catalyst, which exhibited enhanced performance. The fabricated Si/SiO x /ITO/a-NiOOH photoanode exhibited a low photocurrent onset potential of ∼0.98 V vs. RHE, a high saturation photocurrent density of 36.98 mA/cm 2 , a photocurrent density of 27.4 mA/cm 2 at the standard oxidation potential of water, and a photovoltage as high as 545 mV under a solar illumination of 100 mW/cm 2 . The photocurrent marginally decreased after 30 h. These results suggested that such heterojunctions can replace homogeneous p–n junctions formed from Si doping for high photovoltage generation. In addition, porous a-NiOOH can improve the electrocatalytic performance of Si-based photoanodes. [ABSTRACT FROM AUTHOR]

The understanding of structural defects in basal-faceted sapphire ribbons was improved through X-ray imaging at a synchrotron source. The combination of phase contrast and X-ray diffraction makes it possible to visualize and characterize both gas voids and dislocations in the bulk of the ribbons grown by the Stepanov–LaBelle technology. Dislocations were directly related to gas voids. X-ray diffraction topography was employed to investigate the distribution, configurations, and character of the dislocations. The formation of voids of irregular shapes was detected by large-area mapping with spatial resolution in the μm range. Computer simulations of the experimental phase contrast images of microvoids were performed. The sizes of the spherical microvoids were determined. The results are discussed with reference to the available data on the emission of dislocations from the voids. The evolution of the shape, size, and arrangement of the voids during growth provides clues on the formation of block structure in basal-faceted sapphire ribbons. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) metal/cuprous oxide (Cu 2 O) micro-pillar arrays were fabricated by electroless deposition of Ni on Si micro-pillars followed by the electrochemical deposition of Cu 2 O on the metal micro-pillars. The metal micro-pillars with heights of 16 μm and diameters of 1–1.5 μm showed low reflectance and conductance values similar to Cu 2 O plates, indicating that the 3D metal/Cu 2 O micro-pillars are good current collectors. The photocurrent of the 3D metal/Cu 2 O micro-pillar arrays was more than twice that of the Cu 2 O plates. This high photocurrent for the 3D metal/Cu 2 O micro-pillar results from its large surface area, long optical absorption depth (micro-pillar length) and short carrier diffusion length (thin Cu 2 O absorber). [ABSTRACT FROM AUTHOR]

The behavior of cement paste is significantly affected by the phase distribution characteristics within the material. However, studying the correlation between the microstructural characteristics and intrinsic properties involves time-consuming experiments. Thus, simulations can help accelerating the process. In this study, a method using micro-CT imaging analysis and nanoindentation within the framework of finite element analysis was proposed to investigate the mechanical properties of the cement paste. The virtual specimen obtained from micro-CT was segmented into four phases: pore, inner and outer hydration products, and unhydrated cement. Subsequently, the material modeling input parameters for each solid phase were determined using a nanoindentation test. The differences in the crack patterns and mechanical properties of the homogenized single and multiple phase solid models were confirmed. In addition, the localized characteristics of crack propagation in the multiple phase solid model were detected, which enable it to reflect a more realistic behavior than the single phase solid model. The modeling input parameters for the outer hydration product, which is the dominant phase of the multiple phase solid model, can be used as a first approximation to predict the microstructural response at reduced computational cost. • Cement paste properties were evaluated using micro-CT and nanoindentation. • The differences in single and multiple phase solid models were confirmed. • Crack development patterns were consistent with the phase distribution profile. • The dominant phase input properties can be used for a first approximation. [ABSTRACT FROM AUTHOR]

Abstract: The scalable, high-throughput, cost-effective synthesis of high-quality tetragonal tellurium (t-Te) nanowires by the galvanic displacement reaction of Si on a 4-in. Si wafer is demonstrated. This method does not require any heterogeneous seeds, physical templates, or surfactants. In addition, because seed nucleation and growth are both instantaneous, the synthesized nanowires had uniform lengths across the substrate. Furthermore, the effects of the deposition conditions, including the solution composition and reaction time and temperature, on the morphologies, dimensions, and crystallinities of the Te nanowires were analyzed to investigate the growth mechanism. The synthesized t-Te nanowires exhibited excellent piezoelectric properties, with the output current being as high as −75.0nA. [Copyright &y& Elsevier]

Abstract: Sb x Te y films were potentiostatically electrodeposited from acidic nitric baths at room temperature by controlling the applied potential. Near-stoichiometric Sb2Te3 thin films were obtained at applied potentials between −0.15 and −0.30V vs. saturated calomel electrode (SCE). Post-annealing in a reducing environment resulted in an improvement in the crystal structure without the evaporation of the Te element. This result was indicated by a significant reduction in the electrical resistance and decrease in the FWHM of the main diffraction peaks. The power factor (σS 2) increased from 44.2 to 372.1μW/mK2 after annealing at 473K. [Copyright &y& Elsevier]

Abstract: Chromosomes are condensed in all forms of life. SMC-based condensins are the key mediators in this process, but their molecular mechanisms remain elusive. Two different condensin complexes have been identified in prokaryotic organisms: MukB–MukE–MukF and SMC–ScpA–ScpB. This review focuses on comparison between the two machineries based on structural, biochemical and other related information in the light of their structure and function. [Copyright &y& Elsevier]

Summary: Condensins are key mediators of chromosome condensation across organisms. Like other condensins, the bacterial MukBEF condensin complex consists of an SMC family protein dimer containing two ATPase head domains, MukB, and two interacting subunits, MukE and MukF. We report complete structural views of the intersubunit interactions of this condensin along with ensuing studies that reveal a role for the ATPase activity of MukB. MukE and MukF together form an elongated dimeric frame, and MukF''s C-terminal winged-helix domains (C-WHDs) bind MukB heads to constitute closed ring-like structures. Surprisingly, one of the two bound C-WHDs is forced to detach upon ATP-mediated engagement of MukB heads. This detachment reaction depends on the linker segment preceding the C-WHD, and mutations on the linker restrict cell growth. Thus ATP-dependent transient disruption of the MukB-MukF interaction, which creates openings in condensin ring structures, is likely to be a critical feature of the functional mechanism of condensins. [Copyright &y& Elsevier]

Abstract: The aim of this work was to obtain uniform and well-dispersed spherical silver nanoparticles using statistical design of experiments. For the purpose, we have performed the experiments based on the statistical design regarding some key factors involved in a general chemical reduction method. The nanoparticles prepared were characterized by SEM, TEM and UV–vis absorbance for particle size, distribution, aggregation and anisotropy. The data obtained were analyzed and optimized using a statistical software. The design of experiments using quantified data enabled us to understand effects of factors and interactions between them. The principal properties of produced nanoparticles were dominated by not only individual one or two main factors but also interactions between factors. The appropriate combination of the factors led to synthesis of small, narrow-distributed and non-aggregated silver nanoparticles of about 30nm with approximately 10% standard deviation. [Copyright &y& Elsevier]

It is self‐evident that our chests expand and contract during breathing but, surprisingly, exactly how individual alveoli change shape over the respiratory cycle is still a matter of debate. Some argue that all the alveoli expand and contract rhythmically. Others claim that the lung volume change is due to groups of alveoli collapsing and reopening during ventilation. Although this question might seem to be an insignificant detail for healthy individuals, it might be a matter of life and death for patients with compromised lungs. Past analyses were based on static post‐mortem preparations primarily due to technological limitations, and therefore, by definition, incapable of providing dynamic information. In contrast, this study provides the first comprehensive dynamic data on how the shape of the alveoli changes, and, further, provides valuable insights into the optimal lung volume for efficient gas exchange. It is concluded that alveolar micro‐dynamics is nonlinear; and at medium lung volume, alveoli expand more than the ducts. [ABSTRACT FROM AUTHOR]

We report on a transparent gallium-doped indium oxide (GIO) ohmic contact to the p-GaN. The GIO contact film yielded a low specific contact resistance of 8.1×10-5 Ω cm2 on p-GaN when annealed at 600 °C under a nitrogen ambient. The low specific contact resistance can be attributed to the formation of acceptorlike Ga vacancies and an InN or InxGa1-xN phase at the interface between the GIO and p-GaN films. The forward voltage of a light-emitting diode (LED) with a GIO ohmic layer was slightly increased by 0.2 V compared to that of a LED with a standard Ni/Au contact. However, a light transmittance of 85.7%, which was higher than that of indium tin oxide, was observed in the GIO film at a wavelength of 470 nm after thermal annealing at 600 °C. These results suggest that the GIO contact scheme is suitable for use as a highly transparent and low specific contact resistance contact layer for p-GaN. [ABSTRACT FROM AUTHOR]

Alcohol ingested by humans can be analyzed via breath tests; however, approximately 1% can be excreted via the skin. In this paper, we present a capacitive sensor using hydrophobically treated anodic aluminum oxide (AAO) capable of detecting alcohol excreted through the epidermis. The degree of hydrophobicity based on the duration of exposure to 3-aminopropyltriethoxysilane vapor comprising a small number of Si–NH2 functional groups on the AAO surface was confirmed and the optimal exposure time was confirmed to be 60 min. The hydrophobized AAO showed a 4.8% reduction in sensitivity to moisture. Simultaneously, the sensitivity of the sensor to ethanol decreased by only 12%. Lastly, the fabricated sensor was successfully operated by attaching it to an ankle-type breathalyzer. [ABSTRACT FROM AUTHOR]

Highlights • Lithium is adsorbed by carboxylic acid and phosphonate groups in brown algae. • Brown algae-inspired pMOF@Alg were fabricated. • pMOF@Alg(Cu) exhibits relatively high Li selectivity by size exclusion. • pMOF@Alg(Al) exhibits relatively high Mg selectivity by partial dehydration. • Fabricated alginate hydrogels were reusable by washing with using ethanol/DI water. Abstract With increasing global demands for lithium resources, the separation of lithium from seawater-based resources has been widely explored. Herein, we propose phosphonate metal organic framework (MOF)-incorporated alginate hydrogels inspired by brown algae. The analysis of Li+ adsorption characteristics of brown algae revealed that carboxylic acid and phosphonate groups were the dominant functional groups for Li+ adsorption. Biomimetic phosphonate MOF-incorporated alginate hydrogels (pMOF@Alg) were fabricated on the basis of the Li+ adsorption characteristics of brown algae. Their adsorption behaviors indirectly evaluated by conductivities showed that the growth of phosphonate MOF in Cu2+-based alginate hydrogel enhances Li+ adsorption but inhibits Mg2+ adsorption with a small difference, which might be attributed to size confinement effect by heterogeneously distributed phosphonate MOF. By contrast, the growth of phosphonate MOF homogeneously distributed in Al3+-based alginate hydrogel greatly enhances Mg2+ adsorption while rejecting Li+ adsorption. This reverse adsorption behavior of pMOF@Alg(Al) seems to be attributed to partial dehydration, depending on the dehydration energy of hydrated metal ions. The adsorbed ions are easily removable by using ethanol/DI water because of the weak electrostatic interaction with negatively charged groups. This study would provide novel selective adsorption methodology for the separation of Li+ and Mg2+ and an effective lithium recovery technology. [ABSTRACT FROM AUTHOR]

The thermoelectric properties of aluminum-doped tin oxide (ATO) thin films synthesized by thermal atomic layer deposition (ALD) were studied with respect to the aluminum concentration. The overall aluminum content in each layer was modulated by adjusting the relative number of tin oxide (SnO 2 ) and aluminum oxide (Al 2 O 3 ) growth cycles, where a sequential process involving n cycles of SnO 2 growth followed by 1 cycle of Al 2 O 3 deposition was performed (building up a super-cycle). The electrical conductivity (620 S/cm), free carrier concentration (1.23x10 21 cm -3 ), and power factor (0.49 mW/K 2 m) increase until their maximum values are reached when the Al content is approximately 1.50 at% of the cations, and decrease as more Al is added in. On the other hand, the Seebeck coefficient decreases monotonically as the Al content increases up to about 2.88 at%, and begins to increase with further Al doping. Here the thermoelectric efficiency is therefore determined primarily by the free carrier concentration, while the Seebeck coefficient appears to be influenced by the overall crystal structure. [ABSTRACT FROM AUTHOR]

The catalytic performance of nanostructured bimetallic hydroxide nanosheets (NSs) on a Ni foam was investigated as a function of the Co/Ni concentration ratio. A facile but highly precise composition-controlled electrodeposition technique was employed to synthesize CoNi-layered double hydroxides (LDH) within tens of seconds; the 0.3/0.2 CoNi-LDH NSs showed the best current density (76.9 mA cm −2 at 1 V (vs. Ag/AgCl)). However, the poor adhesion of the CoNi-LDH NSs on the Ni foam decreased the current density to 82% at 1 V (vs. Ag/AgCl) after 10 h. The manipulation of the surface of the Ni foam via the deposition of Ni nanocones (NCs) enhanced the long-term stability to 92.6% and led to an overpotential of 366 mV and a current density of 111.5 mA cm −2 at 1 V (vs. Ag/AgCl) in 1 M KOH alkaline solution. Thus, the CoNi LDH NSs on the surface-modified Ni foam are a promisingly efficient and stable oxygen evolution reaction (OER) catalyst. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (ZIBs) are attractive in energy storage due to the use of aqueous electrolytes that ensures safety and ease of handling all parts in air. However, catastrophic zinc dendritic growth on zinc metal anodes impedes their practical application. Herein, Zn3(PO4)3·4H2O (ZP)‐coated zinc metal anode is introduced to effectively suppress the dendrite growth and the chemical state of the dendrites that are composed of metallic Zn0, ZnO, and Zn(OH)2 is elucidated first. Significant improvement is observed for the ZP‐coated zinc metal symmetric cell. Operando synchrotron tomography demonstrates that the ZP‐coating layer ensures uniform deposition of zinc‐derived compounds by the ZP layer that scarifies itself through decomposition to P2O5, Zn0, and Zn(OH)2. Meanwhile, the local reaction between P2O5 and H2O reproduces H3PO4, which provides a condition to reproduce Zn3(PO4)2·4H2O via a reaction between H3PO4 and metallic Zn on the Zn metal anode. This cyclic reformation of Zn3(PO4)2·4H2O progressively prevents dendrites over the long‐term, even at high rates. The compatibility is verified in NaV3O8||ZP‐coated zinc anode cell over 1000 cycles. As a result, this finding presents a practical way for uniform deposition of Zn that can be applicable to aqueous and nonaqueous ZIBs. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Hydrogen sensors are critical in fuel cell applications, where carbon monoxide (CO) poisoning presents a substantial limitation to sensor longevity. The broad flammability range of hydrogen (from percentages to ppm) underscores the need for precise and efficient detection methods. Traditional approaches employ catalysts, but suffer from limitations such as poor control over catalyst characteristics, limited robustness, and slow response times, under CO poisoning. This study introduces an innovative approach for hydrogen detection in extreme environments by controlling the hydroxyl (OH-) functional groups and significantly decreasing the Pt particle size from 10 nm to 2 nm, which enhances catalytic activity and stability. This enhancement enables wide-range detection and rapid response even under CO poisoning. Our results demonstrate the development of a superior Bluetooth-enabled hydrogen-cap sensor that operates reliably at room temperature in various harsh industrial environments, highlighting its potential applicability and robustness in real-world scenarios. [Display omitted] • Developed Pt/MF3 sensor detects H₂ from 5 % to 500 ppm at room temperature. • AAO substrate's porosity enables fast response and recovery times. • Optimal 2 nm Pt nanoparticles stable response and CO resistance. • Bluetooth integration advances portability and IoT connectivity. • Work bridges nanotech and smart monitoring for industry and environment. [ABSTRACT FROM AUTHOR]

Silver antimony telluride (AgSbTe 2 ) thin films were fabricated by a simple and cost-effective electrodeposition method for the first time. To investigate the effects of crystallinity and composition on the films’ thermoelectric (TE) properties, amorphous Ag x Sb y Te z solid solutions of various compositions were electrodeposited by tailoring the [Ag + ] concentration in the electrolytes, followed by a thermally driven solid-state amorphous-to-nanocrystalline phase transition. Because of the lower carrier concentration in the nanocrystalline phases, higher Hall mobility and Seebeck coefficients, almost twice as high as those observed in the bulk materials, resulted in enhanced power factors of 90–553 μW/mK 2 . The maximum power factor was obtained from stoichiometric AgSbTe 2 thin films. The reported power factors are highly comparable to other values reported for electrodeposited p-type V–VI compounds. The improvement achieved in the TE properties of electrodeposited AgSbTe 2 thin films demonstrates the feasibility of the use of these films as p-type legs in room-temperature operations. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanoparticles decorated single walled carbon nanotubes (SWNTs) were electrochemically synthesized where the deposition conditions were systematically explored to tailor the size, density, and microstructure of the ZnO nanoparticles and correlated to the gas sensing performance. Room temperature conductometric detection of various analytes including CO, CO2, NO2, NH3, SO2, H2S with ZnO/SWNT hybrid nanostructures demonstrated uncharacteristic selectivity towards H2S with little to no response for the other analytes examined. Optimal ZnO/SWNTs gas sensor devices showed a significantly increased in H2S sensitivity over unfunctionalized SWNT networks (i.e. 4.96 % per ppmV vs. 0.225 % ppmV) with a lower detection limit in the ppb range. Additionally, the H2S sensing performance was greatly improved by enhancing the crystallinity of ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: Microstructural and electrical properties of potentiostatically electrodeposited ZnO thin films from an aqueous bath were investigated after annealing at different temperatures in Ar and 5% H2/Ar atmospheres. It is confirmed that the bandgap energy of ZnO thin films decreased with annealing from 3.42 to 3.27–3.29 eV by calculating the wavelength of the absorption region. The annealing at temperatures as low as 200 °C decreased the sheet resistance of ZnO thin films because of the extinction of Zn(OH)2 in the atmosphere. In addition, the sheet resistance of ZnO thin films decreased by annealing in a 5% H2 atmosphere, which caused an increase of carrier concentration by hydrogen reduction. [Copyright &y& Elsevier]

Background: Pulmonary valve replacement (PVR) is often performed in patients with repaired tetralogy of Fallot (TOF). Concomitant tricuspid valvuloplasty (TVP) in those with tricuspid regurgitation (TR) at the time of PVR is still controversial. Method: We retrospectively reviewed clinical records of patients who underwent PVR between 2001 and 2012. We analyzed the impact of concomitant TVP on the tricuspid valve function and right ventricle function and size in mid-term. Results: 119 patients with mild to moderate TR at the time of PVR were enrolled. 33 patients underwent concomitant TVP (TVP group) and 86 patients underwent PVR alone (no-TVP group). There was a significant reduction of TR (p < 0.001) and right ventricular end-diastolic volume index (RVEDVi) (p < 0.001). However, in patients who showed prosthetic pulmonary valve (PV) failure at the last follow-up, there was no significant decrease in TR regardless of concomitant TVP. In the patients with preserved prosthetic PV function, TR was significantly improved (p < 0.001 in both groups). The multivariable analysis showed that significant risk factors for recurrence of significant TR were preoperative moderate TR and prosthetic PV failure. Conclusions: After PVR in repaired TOF patients, there was an improvement in the degree of TR and the RVEDVi. Concomitant TVP at the time of PVR may not be able to prevent the recurrence of TR when prosthetic PV failure occurs; however, it may effectively preserve tricuspid valve function until that time. [ABSTRACT FROM AUTHOR]

Summary: Tillandsia usneoides in epiphytic bromeliads takes up water through 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, its water transport remains unclear.We characterized structures of trichome wings of T. usneoides. Wing length‐to‐thickness ratio of 136 and trichome interval (d)‐to‐wing length (l) ratio (d/l) smaller than 1 caused the water film to flatten the wings sequentially, resulting in 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.Tillandsia 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 flexible wing arrays. [ABSTRACT FROM AUTHOR]

The new Brain Imaging Beamline (BIB) of the Taiwan Photon Source (TPS) has been commissioned and opened to users. The BIB and in particular its endstation are designed to take advantage of bright unmonochromatized synchrotron X‐rays and target fast 3D imaging, ∼1 ms exposure time plus very high ∼0.3 µm spatial resolution. A critical step in achieving the planned performances was the solution to the X‐ray induced damaging problems of the detection system. High‐energy photons were identified as their principal cause and were solved by combining tailored filters/attenuators and a high‐energy cut‐off mirror. This enabled the tomography acquisition throughput to reach >1 mm3 min−1, a critical performance for large‐animal brain mapping and a vital mission of the beamline. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

• Microstructural changes in cement paste from carbonation are investigated through image analysis of microstructures obtained from a synchrotron micro-CT. • Porosity reduction after carbonation is captured from the image analysis. • The grayscale values (linear attenuation coefficient) of micro-CT images are reduced after carbonation. • The grayscale values of micro-CT images do not necessarily increase although the material density increases after carbonation as can be confirmed by the theory. The carbonation of cement paste changes its microstructural characteristics. The porosity of the cement paste microstructure is reduced when calcite is produced from the reaction between portlandite and carbon dioxide. In this study, such microstructural changes were investigated using image analyses of the 3D microstructures obtained with synchrotron micro-computed tomography (CT). When two sets of samples were subjected to different degrees of carbonation, the porosity and pore size reductions were identified from the micro-CT images. The formation of calcite caused by the reaction of portlandite was indirectly identified by the reduction of the mean grayscale value or linear attenuation coefficient (LAC) of the solid phase voxels. It was confirmed that micro-CT could also be used as a supplementary tool for the analysis of the microstructural evolution of cement paste under carbonation. [ABSTRACT FROM AUTHOR]

The addition of Cu becomes essential in polycrystalline n -type Bi 2 (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 Cu 0.008 Bi 2 Te 2.7 Se 0.3. 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. Image, graphical abstract [ABSTRACT FROM AUTHOR]

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 Bi 0.5 Sb 1.5 Te 3 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. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The effect of electrical current on the hydrogen incorporation into single crystalline ZnO was investigated. The current-voltage characteristics of single crystalline ZnO were measured as a function of the electrical conductivity of ZnO. The electrical current of ZnO was significantly increased at the second sweep of voltages when the electrical conductivity of ZnO was higher than 0.32 S/cm. A depth profiling analysis of ZnO by dynamic secondary ion mass spectrometry indicated that the hydrogen atoms were incorporated to form hydrogen-related donors, such as a substitutional hydrogen (HO) and an interstitial hydrogen (Hi), which resulted in an increase in the donor concentration of ZnO. [ABSTRACT FROM AUTHOR]

The ZnO-based metal-insulator-semiconductor (MIS) diode was fabricated by using an insulator ZnO layer and an n-ZnO layer grown by radio frequency magnetron sputtering. The current-voltage of the ZnO MIS diodes showed a good diode characteristic with a threshold voltage of 8.9 V and a band-edge emission at 380 nm at room temperature. The electroluminescence emission of ZnO MIS was attributed to the generation of holes in the insulating ZnO layer at the high threshold voltage of 8.9 V via an impact ionization process. [ABSTRACT FROM AUTHOR]

High quality Pt Schottky contact to n-type ZnO was formed using KrF excimer laser. A pulsed laser irradiation of n-type ZnO in O2 pressure of 0.1 Mtorr, prior to Pt metal deposition, considerably improved the rectifying characteristics. The Schottky barrier heights of 0.73 and 0.85 eV were obtained from the current-voltage (I-V) and capacitance-voltage (C-V) measurements, respectively. The cathodoluminescence and Auger electron spectroscopy results indicated that the improvement in rectifying characteristics can be attributed to a removal of surface carbon and hydrogen contaminants and a reduction of subsurface donorlike point defects by the KrF excimer laser irradiation. [ABSTRACT FROM AUTHOR]

The authors report on the thermal activation of phosphorus doped p-type ZnO thin films grown by radio frequency magnetron sputtering. The p-type ZnO was produced by activating phosphorus doped ZnO thin films in N2, Ar, or O2 ambients. The hole concentration of the p-type ZnO, prepared in an O2 ambient, showed a lower hole concentration compared to samples annealed in N2 and Ar ambients. The activation energies of the phosphorus dopant in the p-type ZnO under different ambient gases indicate that phosphorus atoms replace oxygen atoms in the ZnO to form PO which acts as an acceptor. [ABSTRACT FROM AUTHOR]

Antimony telluride thin films display intrinsic thermoelectric properties at room temperature, although their Seebeck coefficients and electrical conductivities may be unsatisfactory. To address these issues, we designed composite films containing upper and lower Sb2Te3 layers encasing conductive poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS)- polyvinylpyrrolidone(PVP) nanowires. Thermoelectric Sb2Te3/PEDOT:PSS-PVP/Sb2Te3(ED) (STPPST) hybrid composite films were prepared by a multi-step coating process involving sputtering, electrospinning, and electrodeposition stages. The STPPST hybrid composites were characterized by field-emission scanning electron microscopy, X-ray diffraction, ultraviolet photoelectron spectroscopy, and infrared spectroscopy. The thermoelectric performance of the prepared STPPST hybrid composites, evaluated in terms of the power factor, electrical conductivity and Seebeck coefficient, demonstrated enhanced thermoelectric efficiency over a reference Sb2Te3 film. The performance of the composite Sb2Te3/PEDOT:PSS-PVP/Sb2Te3 film was greatly enhanced, with σ = 365 S/cm, S = 124 μV/K, and a power factor 563 μW/mK. [ABSTRACT FROM AUTHOR]

Herein, we report the enhanced thermoelectric performance of Cu incorporated Bi 2 Te 2.7 Se 0.3 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 Cu 0.008 Bi 2 Te 2.7 Se 0.3 , which is ~30% enhancement in comparison with pristine Bi 2 Te 2.7 Se 0.3. This result can lead to high thermoelectric power generation efficiency 4.2% at Δ T = 180 K. Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract Controllable crystal orientation is necessary to obtain high thermoelectric performance in thin films of Bi 2 Te 3 alloys. In the present study, highly (110)-oriented thin films of n-type Bi 2 Te 3- x Se x 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 Bi 2 Te 3- x Se x 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 Bi 2 Te 3- x Se x 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 Bi 2 Te 3 -based thin films, was obtained at room temperature after low-temperature annealing at 200 °C by exploiting the crystallinity enhancement and carrier concentration optimization. Graphical abstract Image 1 Highlights • Modified pulsed electrodeposition was used to fabricate n-type BiTe 3- x Se x TE films. • Fabrication method enabled high compositional and morphological control. • Annealing improved crystallinity; TE power factor was high at room temperature. • Further improving crystallinity may further improve TE figure of merit. [ABSTRACT FROM AUTHOR]

A novel method for fabrication of a thermochemical hydrogen (TCH) gas sensor composed of platinum (Pt)-decorated graphene sheets and a thermoelectric (TE) polymer nanocomposite was investigated. The hydrogen sensing characterization for the device included gas response, response time (T 90), recovery time (D 10), and reliability testing, which were systematically conducted at room temperature with a relative humidity of 55%. Here, the Pt-decorated graphene sheets act as both an effective hydrogen oxidation surface and a heat-transfer TE polymer nanocomposite having low thermal conductivity. This property plays an important role in generating output voltage signal with a temperature difference between the top and bottom surfaces of the nanocomposite. As a result, our TCH gas sensor can detect the range of hydrogen from 100 ppm to percentage level with good linearity. The best response and recovery time revealed for the optimized TCH gas sensor were 23 s and 17 s under 1000 ppm H 2 /air, respectively. This type of sensor can provide an important component for fabricating thermoelectric-based gas sensors with favorable gas sensing performance. • A novel-type of TE composite-based hydrogen gas sensor was fabricated. • Gas response of the sensor was considerably linear at low- and high concentrations. • The sensor has a detection limit of 100 ppm with high signal to noise ratio. • The response/recovery times were 23 s and 17 s under 1000 ppm H 2 /air, respectively. [ABSTRACT FROM AUTHOR]

The pore distribution of a cement paste strongly affects its mechanical behavior such as its stiffness and strength. Porosity is an influential parameter that can be used to identify the complex pore microstructures of cement paste, but it has limitations as a scalar parameter. In this study, the lineal-path function, a low-order probability function, is investigated as a supplement or an alternative parameter for describing the microstructural characteristics of cement paste microstructures. In particular, the area of the lineal-path function is used as a measure of the pore microstructural characteristics, which can be linked with its properties. A relatively new method for simulating crack propagation, the crack phase field model, is used to evaluate the stiffness and tensile strength of cement paste microstructures and the evaluated properties are linked to the proposed characterization parameters. The evaluation is performed on virtual specimens obtained from micro-level computerized tomography ( μ -CT) images of real cement paste specimens. The validity of the microstructure-property relations obtained from the proposed characterization parameters and the crack phase field model are confirmed through the statistical analysis of dozens of specimens. It is concluded that the correlation between the area of the lineal-path function and the mechanical properties is very strong. The parameter could potentially be used as a supplementary or an alternative parameter to describe the pore microstructures of cement paste. [ABSTRACT FROM AUTHOR]