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Transparent and electromagnetic (EM) shielding Co-doped SnO 2 (CTO) thin films were fabricated using ultrasonic-assisted spray pyrolysis deposition. Structural and chemical investigations showed that the Co2+ ions were substitutionally incorporated into the Sn4+ lattice sites of the SnO 2 crystal and that the Co concentration increased with increasing the Co source content. The incorporated Co ions acted as a magnetic dopant and as an electrical acceptor to compensate for the free charge carriers in SnO 2. Co-doping could modulate the two conflicting efficiencies of the EM shielding performance in the frequency range of 1.5–18 GHz and the infrared transmittance of the SnO 2 thin films. • Co-doped SnO 2 thin films were deposited using a spray pyrolysis deposition method. • The Co ions acted as a magnetic dopant and electrical acceptor in SnO 2. • Co-doped SnO 2 showed electromagnetic shielding performance and IR transmittance. [ABSTRACT FROM AUTHOR]

We report the fabrication of p -SnO 2 thin films by spray pyrolysis deposition using europium (Eu) as an acceptor. Structural and chemical investigations verified that Eu3+ ions were successfully incorporated into the SnO 2 crystal by substituting the Sn4+ sites in the lattice. Even though the undoped SnO 2 thin film showed n -type properties with a charge carrier concentration of −2.343 × 1018 cm−3, SnO 2 showed p -type properties as the Eu was incorporated. In addition, the charge carrier concentration of the Eu-doped SnO 2 increased to 9.121 × 1019 cm−3 as the molar content of the Eu source was increased to 0.2 mM. The optical transmittance was not degraded by the Eu doping and was maintained between 70 and 80% in the visible wavelength spectral range, while the optical band gap of the Eu-doped SnO 2 increased due to the Burstein-Moss effect. The thin film field-effect transistor fabricated by using the Eu-doped SnO 2 showed the typical gate-modulated drain current characteristic of a p -channel transistor with depletion mode. These results demonstrated the effectiveness of Eu as a dopant for p -SnO 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zn-doped SnO 2 thin film was grown by dual source spray pyrolysis deposition (Co-SPD). • The Zn incorporation rate into the SnO 2 was improved by using the Co-SPD process. • The Zn-doped SnO 2 films showed enhanced infrared transmittance even at elevated temperatures. Recently, SnO 2 has attracted much attention for optoelectronic applications in infrared (IR) spectral ranges due to its high transparency in the ultraviolet to IR wavelength spectral range and high electrical conductivity. The transition metal-doped SnO 2 based on the ultrasonic-assisted spray pyrolysis deposition (SPD) method has been widely used for various optoelectronic applications. However, the SPD process has suffered from inefficient doping of foreign elements due to difficulties in controlling the single precursor source solutions and complicated solution dynamics. To overcome these problems, the co-SPD process supplying the host and dopant solutions separately was suggested for the deposition of the Zn-doped SnO 2 thin films. The Zn-doped SnO 2 thin films deposited by co-SPD showed insulating electrical properties due to the efficient incorporation of the Zn element as an oxygen vacancy scavenger and acceptor to annihilate the free charge carriers. Also, the Zn-doped SnO 2 films showed an IR transmittance of over 80 %, maintained at a temperature of up to 500 ℃. Thus, the co-SPD process can be a promising approach to achieve highly doped oxide films with high IR transmittance even at elevated temperatures. [ABSTRACT FROM AUTHOR]

Recently, copper-based lead-free perovskites have emerged as a promising material due to their unique physical properties, abundance on earth, and lower toxicity. Among them, CsCu 2 I 3 has received extensive attention for optoelectronic device applications due to its excellent air stability and stable self-trapped exciton-based yellow emission. However, the inherent one-dimensional crystal structure of CsCu 2 I 3 -based perovskite makes it difficult to control the morphology during the synthesis process, which results in a high density of pinhole defects on the thin films. Here, we reported a strategy to obtain a high-quality and pinhole-free CsCu 2 I 3 thin film by modifying growth kinetics by adding I 2 during synthesis. The I 2 -modified CsCu 2 I 3 film improved surface morphology while preserving crystalline and optical properties. Therefore, the ultraviolet (UV) photodetector based on the I 2 -modified CsCu 2 I 3 film showed enhanced performances in the solar-blind waveband, including a high responsivity of 1.74 μA/W and fast response and recovery times of 0.684 and 0.686 s, respectively. Finally, the solar-blind UV photodetector based on the I 2 -modified CsCu 2 I 3 thin film exhibited outstanding demonstration in optical communication systems without ambient interference, indicating its potential for various optoelectronic applications. [Display omitted] • Pinhole-free CsCu 2 I 3 perovskite thin film was fabricated by the iodine-modification process. • The surface modification mechanism of CsCu 2 I 3 thin film by iodine treatment was suggested. • Iodine-treated CsCu 2 I 3 thin film enhanced the performance of solar-blind ultraviolet photodetector. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO x), a representative transparent p -type semiconductor, has been a promising candidate for hole transport layer (HTL) in perovskite-based photovoltaic and light-emitting diode (LED) devices due to its high chemical stability and high transparency. However, the interface between the NiO x and perovskite emission layers shows a relatively large electrical barrier for the holes to be transported, which degrades the interfacial electrical properties. To overcome these problems, we suggest a mild oxygen plasma treatment on the NiO x surface to introduce Ni vacancies while retaining its advantages. By controllably forming the Ni vacancies, the hole concentrations could be controlled, which modulated the valence band edge level. This increases the work function of NiO x from 4.979 to 5.364 eV, which facilitates the hole transport at the interface between NiO x HTL and the perovskite emission layer. Ultimately, the overall process leads to improved electroluminescence intensity, reduced driving voltage reduction, and low charge trap density at the interface between the NiO x HTL and the perovskite emission layers. These eventually improved the external quantum efficiency of the perovskite light-emitting diodes. • Modification mechanism of NiO x surface by oxygen plasma treatment was suggested. • The electrical and chemical properties of NiO x were modulated by mild oxygen plasma treatment. • Plasma-treated NiO x film enhanced the performance of the all-inorganic perovskite light-emitting diode. [ABSTRACT FROM AUTHOR]

Wearable mechanical energy harvesting technologies have been achieved much attention for the wireless sustainable power source applications. In this study, we have fabricated polyvinylidene fluoride (PVDF)/graphene quantum dot (GQD) composite nanofibers (NFs), which showed improved triboelectric nanogenerator (TENG) performance. PVDF/GQD composite NFs were fabricated by an electrospinning method. Structural and chemical investigations show that the GQDs were embedded in the PVDF NFs and promoted the formation of polar β-phase when an optimal amount of GQDs was incorporated. The PVDF/GQD NFs showed strong photoluminescence at a wavelength of 453 nm, which was attributed to the electronic transitions in the GQDs. As the GQD content increased from 0 to 5 vol%, the maximum output power from TENG devices increased from 35 to 97 μW but decreased with further additions of GQDs. The enhancement and degradation of the TENG performance with increasing the GQD contents were due to the enhanced formation of polar β-phase and the detrimental effect of conductive GQDs for charge trapping, respectively. • Polyvinylidene fluoride/graphene quantum dot composite nanofibers were fabricated. • Graphene quantum dot enhanced β -phase in the polyvinylidene fluoride nanofibers. • Incorporation of graphene quantum dot enhanced triboelectric nanogenerator performance. [ABSTRACT FROM AUTHOR]

Abstract The effect of ethanol addition during milling on the milling performances of Ta-hydride powders was investigated for hydride and dehydride processes during Ta recycling process. As the Ta-hydride was milled in a conventional dry atmosphere, Ta 2 O was dominantly formed due to the increased temperature of the Ta-hydride pieces because they were rubbed against each other and crushed by the ring mill system. However, with the addition of ethanol solvent, the ratio of the Ta 2 H phase increased compared to the Ta 2 O phase, and the size of the powders reduced and became more uniform. These were attributed to the enhanced hydride formation and reduced contact between the Ta-hydride powders and air by wetting them. Therefore, an optimum amount of ethanol addition and milling time can enhance the formation of additional Ta-hydrides, while preventing oxidation during milling. Highlights • Chemical and structural properties of Ta-hydride during mechanical milling are reported. • Ethanol addition during milling of Ta-hydride enhanced hydrogen incorporation. • Ta-hydride being milled in conventional dry atmosphere was easily oxidized. [ABSTRACT FROM AUTHOR]

• Electrical properties of CuI thin film were modulated by trimethylsilyl iodide treatment. • Trimethylsilyl iodide did not change the optical transmittance and surface morphology of CuI. • Performances of p -CuI/ n -ZnO diodes were enhanced by the trimethylsilyl iodide treatment. This paper reports a facile method to modulate the electrical properties of copper iodide (CuI) thin films, which have attracted considerable attention as a promising transparent conducting p -type semiconductor. Trimethylsilyl iodide (TMSI) was used as an agent for the fast iodination treatment of p -CuI, even at a low processing temperature of 60 °C. A TMSI treatment of less than 30 µL was effective in improving the surface morphology of CuI thin films. The optimal TMSI treatment with 20 µL enhanced the electrical properties of p -CuI by increasing the hole concentration without degrading the optical transmittance. As the TMSI content increased from 0 to 20 µL, the hole concentration of the CuI thin films increased from 4.06 × 1019 to 8.82 × 1019 cm−3. The TMSI treatment eliminated I-vacancies while forming Cu-vacancies that acted as an acceptor dopant. Therefore, the hole concentration in CuI thin films increased with the TMSI treatment. The performance of p -CuI/ n -ZnO diodes, such as on/off ratio, turn-on voltage, and ideality factor, was enhanced by the facile TMSI treatment. [ABSTRACT FROM AUTHOR]

We report on the evolution of the emission and chemical properties of Eu-doped ZnAl-Layered double hydroxide (LDH) with variation of Eu doping concentration during the hydrothermal growth. With increasing Eu source concentration, the morphologies of the ZnAl-LDHs became denser and more closely packed while maintaining the thickness of each plate. As the Eu source concentration increased to 10 wt%, specific emission from the doped Eu 3+ ions was enhanced in the photoluminescence spectra. However, the peak intensity decreased when the concentration increased further to 20 and 30 wt%. X-ray photoelectron spectroscopy results showed an abnormal increase of the Eu 2+ /Eu 3+ ratio in the LDHs with increasing Eu source concentration, which suppressed the emission from the Eu 3+ electronic transitions. [ABSTRACT FROM AUTHOR]

We report on the theoretical and experimental investigations about the Ta-hydride formation depending on the temperature for recycling of Ta scraps. The structural investigations based on scanning electron microscope and X-ray diffraction (XRD) showed that the amount of hydrogen incorporated into the Ta matrix varied with hydridation temperature. The XRD measurement showed that the H/Ta mole ratio in Ta-hydride increased with increasing the hydridation temperature up to 700 °C and then decreased with increasing the temperature furthermore. Depending on the hydridation temperature, various phase of Ta-hydride, such as TaH 0.93 and Ta 2 H were formed and this hydride process was verified by thermodynamic analysis. [ABSTRACT FROM AUTHOR]

Pure and Mg doped ZnO nanorod films were grown on p type silicon substrates by two step hydrothermal method. A solution of 60 mM concentration (by mixing zinc acetate with ethyl alcohol) is made for seed layer deposition. The main growth of pure ZnO and Mg [2 and 5 weight percent (wt%)] doped ZnO nanorod films were done after growing seed layer of undoped ZnO. The structural morphology of the pure and Mg doped ZnO nanorod (NR) films were characterized by X-ray diffraction and scanning electron microscopy. All the NRs were grown well on the ZnO seed layers and their top surface was hexagonal in shape. The electrical characterization of the Pd/ZnO and Pd/MgZnO NR Schottky contacts were studied by using microprobe arrangements. The values of ideality factor, barrier height and reverse saturation current were calculated from I to V characteristics of Schottky diodes. The study demonstrates that Pd/ZnO and Pd/MgZnO NR Schottky contacts fabricated by a simple and inexpensive method can be used as a substitute of conventional Schottky diodes for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Although metal oxides exhibit high electrical conductivity and high transparency in the visible wavelength range, they suffer from low transmittance in the infrared (IR) spectral range. This paper reports the deposition of Sm-doped SnO 2 thin films with high IR transparency by modulating the electrical and optical properties. The Sm-doped SnO 2 thin films grown by spray pyrolysis showed a directional columnar structure and a change in crystal structure from tetragonal to orthorhombic with increasing Sm doping content. The undoped SnO 2 thin film exhibited intrinsic n -type conductivity with a high background charge carrier concentration, which resulted in low IR transmittance of <20%. As the Sm doping content increased, the charge carrier concentration decreased drastically, resulting in an increase in IR transmittance of SnO 2 thin films from 18.8 to 85.2%. The Sm element acted a critical role in controlling the electrical and optical properties of SnO 2 thin films by acting as a reducing agent and dopant. [Display omitted] • Sm-doped SnO 2 thin film was grown by spray pyrolysis deposition method. • Infrared transmittance of SnO 2 thin films was enhanced by doping the Sm element. • An enhancementnt mechanism of IR transmittance was suggested based on the crystalline and defect modifications. [ABSTRACT FROM AUTHOR]

We report on the enhancement of the output voltage from ZnO nanorod (NR)-based piezoelectric nanogenerators (PNGs) fabricated by using a double-sided stainless steel (SUS) substrate. The ZnO NRs were successfully grown on both sides of the SUS substrate by using a hydrothermal method. The ZnO NRs showed different crystalline quality on the front and back sides of the SUS substrate due to different surface morphologies of the sides. The PNGs on the SUS substrates showed typical piezoelectric output performance. The voltage output from the PNGs on the double-sided SUS substrate was much larger than that of the PNGs on the front side or back side of the SUS substrate. In particular, the PNG on the double-sided SUS substrate showed a 1.12–1.66 times larger voltage output compared to the sum of the voltage output from PNGs on both sides of the substrate. This abnormal enhancement of voltage output is due to the electric field-induced synergetic effect between two front side and back side PNGs and to the modification of the electrical properties of the SUS substrate under an electric field generated by PNGs on the surface of each side. [ABSTRACT FROM AUTHOR]

Al-doped ZnO (AZO)/Ag grid hybrid transparent conductive electrode (TCE) structures were fabricated at a low temperature by using electrohydrodynamic jet printing for the Ag grids and atomic layer deposition for the AZO layers. The structural investigations showed that the AZO/Ag grid hybrid structures consisted of Ag grid lines formed by Ag particles and the AZO layer covering the inter-spacing between the Ag grid lines. The Ag particles comprising the Ag grid lines were also capped by thin AZO layers, and the coverage of the AZO layers was increased with increasing the thickness of the AZO layer. Using the optimum thickness of AZO layer of 70 nm, the hybrid TCE structure showed an electrical resistivity of 5.45 × 10 −5 Ω cm, an optical transmittance of 80.80%, and a figure of merit value of 1.41 × 10 −2 Ω −1 . The performance enhancement was suggested based on the microstructural investigations on the AZO/Ag grid hybrid structures. [ABSTRACT FROM AUTHOR]

• Polyvinylidene fluoride/fullerene composite nanofibers were fabricated based on electrospinning process. • Fullerene increased the electronegativity of polyvinylidene fluoride nanofibers. • Incorporation of fullerene enhanced output power of triboelectric nanogenerator from 129 to 282 μW. Recently, sustainable energy harvesting technologies have received much attention for powering the internet of things architecture. Triboelectric nanogenerators (TENGs) have been regarded as the most promising energy harvesting technology because they can generate a large amount of electrical energy even with very weak mechanical energy and very simple structures. Although there has been much investigation, TENG devices continue to be associated with insufficient levels of converted electrical power. In this study, we report the enhancement of TENG performance outputs based on polyvinylidene fluoride (PVDF)/fullerene (C 60) composite nanofibers (NFs). Structural and chemical investigations show that C 60 is uniformly incorporated into PVDF NFs with C 60 content levels of less than 0.3 mg. PVDF/C 60 composite NFs exhibit a consistent β-phase ratio regardless of the C 60 content. Here, as the C 60 content was increased from 0 to 0.2 mg, the maximum output power of the PVDF/C 60 composite NF-based TENG devices increased from 129 to 282 μW, while it decreased to 147 μW with further addition of C 60 beyond 0.4 mg. The enhanced TENG performance realized with an increase in the C 60 content originated from the increased trap charge ability and the high electronegativity caused by the incorporated C 60 in the PVDF matrix. The output power from a PVDF/C 60 composite NF-based TENG device was sufficient to operate an eco-friendly display device. [ABSTRACT FROM AUTHOR]

• Mo nanoparticle decorated thermoelectric nanocomposite was fabricated. • Mo nanoparticles were fabricated by a sacrificial organic supporting method. • The nanocomposite showed enhanced thermoelectric performances due to Anderson localization effect. Although thermoelectric energy conversion technology has received much attention because of its noiseless and economical operations, a low figure of merit (ZT) values of thermoelectric materials has prevented a wider variety of practical applications. Recently thermoelectric composite structures with metal or oxide nanoparticles have been widely investigated to enhance the ZT values by increasing the power factor and decreasing the thermal conductivity simultaneously. However, the difficulties in distributing the nanoparticles in the thermoelectric material matrix homogeneously have been the main problem. Herein we fabricated a thermoelectric nanocomposite structure by decorating the Mo nanoparticles on the surface of Bi 2 Te 2.7 Se 0.3 powders. The Mo nanoparticles were uniformly coated on the Bi 2 Te 2.7 Se 0.3 powder surface based on the sacrificial organic supporter composite consisting of Mo-coated glucose. The Mo nanoparticle/Bi 2 Te 2.7 Se 0.3 composites exhibited a simultaneous decrease of thermal conductivity and electrical resistivity due to an Anderson localization effect. Therefore, the Mo nanoparticle composite structure showed enhanced ZT values by 1.31 times compared to that of bare Bi 2 Te 2.7 Se 0.3 powders exhibiting a ZT value of 0.67 at 373 K. [ABSTRACT FROM AUTHOR]

Cesium lead halide (CsPbX 3 ; X = Cl, Br, and I)-based nanocrystals (NCs) are an attractive optoelectronic material for next-generation lighting and display applications. Except for green-emitting CsPbBr 3 -based NCs, however, there are few investigations for another visible wavelength spectral-ranged color emitters, such as yellow, orange, and red light-emitting diodes (LEDs). This paper reports a facile synthesis of CsPb(Br 1-x I x) 3 NCs emitting wavelengths from green to red based on a halide exchange post-treatment using a trimethylsilyl iodide (TMSI) additive. Microstructural and optical investigations showed that the TMSI modulated the iodine content of CsPb(Br 1-x I x) 3 NCs, resulting in a successive shift of photoluminescence peaks from 510 to 663 nm. Based on CsPb(Br 1-x I x) 3 NCs, LEDs emitting from green to red wavelengths were demonstrated. Interestingly, CsPb(Br 1-x I x) 3 NCs exhibited abnormal electroluminescence (EL) spectra, showing a large red-shift and additional peaks corresponding to the pristine CsPbBr 3 NCs. These were attributed to the modification of CsPb(Br 1-x I x) 3 NCs during the LED fabrication process as well as electrical field-induced phase-segregation during operation. • A facile synthetic method of CsPb(Br 1-x I x) 3 mixed halide perovskite alloyed nanocrystals is reported. • Green, orange, and red light-emitting diodes were demonstrated by CsPb(Br 1-x I x) 3 nanocrystals. • CsPb(Br 1-x I x) 3 nanocrystals exhibited double electroluminescence spectra due to phase separation. [ABSTRACT FROM AUTHOR]

• We investigated the morphological evolution of NiCo hydroxides due to carbonate ions. • The NCCH16//AC device shows the maximum energy densities of 31.1 Wh·kg−1. • The hierarchical NiCo hydroxides exhibit excellent electrochemical performance. Pseudocapacitors can exhibit higher capacity compared to traditional electrostatic or electric double-layer capacitors while they can provide faster power delivery and longer cycling ability than lithium–ion batteries. In this study, we demonstrate the hierarchical structures of NiCo hydroxides, which are grown on Ni foam via facile hydrothermal method and show enhanced pseudocapacitor performance. Moreover, we suggest the intriguing phase transformation of NiCo-layered double hydroxide (LDH) to NiCo-carbonate hydroxide (CH) and elucidate the morphological evolution mechanism from nanosheet to nanowire structures by increasing the concentration of carbonate anions during the synthesis procedure. The experimental results confirm that an increase of carbonate anions causes the phase and morphology of NiCo–LDH to transform into NiCo–CH. Consequently, the asymmetric device using NCCH16 electrode achieves excellent electrochemical performance, with an energy density of 31.1 Wh·kg−1 at a power density of 424.3 W·kg−1 due to their structural benefits, which provide effective electrolyte transport, charge transfer, and active site accessibility. [ABSTRACT FROM AUTHOR]

Accurate and timely diagnosis of Alzheimer's disease (AD) is necessary to maximize the effectiveness of treatment and using biomarkers for diagnosis is attracting attention as a minimally invasive method with few side effects. Electrochemical immunosensor (EI) is a method that is in the spotlight in the medical and bioanalytical fields due to its portability and field usability. Here, we quantified four AD specific biomarkers using EIs based on enzyme immunoassay. We selected and developed quantitative methods for the biomarkers using screen-printed gold electrodes. For three biomarkers, quantification was performed using competition immunoassays in which antigen-antibody premix mixtures were applied to antigen-immobilized electrodes and the limit of detection (LOD) values were secured, 1.20 ng/ml, 1.30 ng/ml, and 1.74 ng/ml, respectively. For the other, a sandwich immunoassay using antibody pair was selected for quantification and LOD was also achieved as 0.077 ng/ml. All four biomarkers in buffer samples were successfully quantified and reliable R 2 values were obtained, and reliable calibration curves were secured for three biomarkers in spiked human serum samples. The immunosensors developed and will be optimized are expected to be used in various fields, including detection of biomarkers for not only AD but also related diseases., (© 2024. The Author(s), under exclusive licence to The Japan Society for Analytical Chemistry.)

Epidemiological evidence suggests that fruit and vegetable intake significantly positively affects cardiovascular health. Since vegetable juice is more accessible than raw vegetables, it attracts attention as a health functional food for circulatory diseases. Therefore, this study measured blood lipids, antioxidants, blood circulation indicators, and changes in the microbiome to confirm the effect of organic vegetable mixed juice (OVJ) on improving blood circulation. This 4-week, randomized, double-blinded, placebo-controlled study involved adult men and women with borderline total cholesterol (TC) and low-density lipoprotein (LDL) levels. As a result, blood lipid profile indicators, such as TC, triglycerides, LDL cholesterol, and apolipoprotein B, decreased ( p < 0.05) in the OVJ group compared with those in the placebo group. Additionally, the antioxidant biomarker superoxide dismutase increased ( p < 0.05). In contrast, systolic and diastolic blood viscosities, as blood circulation-related biomarkers, decreased ( p < 0.05) in the OVJ group compared with those in the placebo group. After the intervention, a fecal microbiome analysis confirmed differences due to changes in the intestinal microbiome composition between the OVJ and placebo groups. In conclusion, our research results confirmed that consuming OVJ improves blood circulation by affecting the blood lipid profile, antioxidant enzymes, and microbiome changes.

To address the increasing demand for multicolor light-emitting diodes (LEDs), a monolithic multicolor LED with a simple process and high reliability is desirable. In this study, organic-inorganic hybrid LEDs with violet and green wavelengths were fabricated by depositing CsPbBr 3 perovskite green quantum dots (QDs) as the light-converting material on InGaN-based violet LEDs. As the injection current was increased, the total electroluminescence (EL) intensities of the hybrid LEDs increased, whereas the light-converted green emission efficiency of the CsPbBr 3 QDs decreased. The maximum green-to-violet EL spectral intensity ratio of the hybrid LEDs with CsPbBr 3 QDs was achieved with the injection current of <10 mA. Moreover, the EL spectral ratio of the green-to-violet emission decreased at an injection current of 100 mA. The light-conversion intensity of the CsPbBr 3 QDs decreased linearly as the junction temperature of the hybrid LEDs was increased with increasing injection current, similar to the temperature-dependent photoluminescence degradation of CsPbBr 3 QDs. In addition, the junction temperature of the hybrid LED was minimized by pulse injection to suppress the thermal degradation of QDs and increase the light conversion efficiency to green emission. Therefore, the overall emission spectrum color coordinates of the hybrid LEDs exhibited a red shift from violet to blue in the low-current region and a blue shift toward violet as the green emission of the QDs was decreased above 10 mA.

A hypertrophic scar is a common dermal fibroproliferative lesion usually treated with topical silicone. Verapamil, a type of calcium channel blocker, is considered a candidate drug for the treatment of hypertrophic scars. Here, we report that the addition of verapamil to topical silicone gel enhances treatment outcomes of hypertrophic scars. Upon creation of hypertrophic scars with the rabbit ear model, varying concentrations of verapamil-added silicone gel (0.1, 1, and 10 mg/g) were applied daily for 28 days. After the animals were euthanised, microscopic measurement was performed for (a) scar elevation index (SEI), (b) fibroblast count, and (c) capillary count. On gross analysis, features of hypertrophic scars were significantly alleviated in the verapamil-added groups. On histologic examination, verapamil-added groups showed (a) reduced SEI (1.93 (1.79-2.67) for control vs 1.34 (1.21-1.51) for silicone only and 1.13 (1.01-1.65) for verapamil-added silicone), (b) fibroblast count 700.5 (599.5-838.5) for control, 613.25 (461-762.5) for silicone only, and 347.33 (182.5-527) for verapamil-added silicone), and (c) capillary formation (52 (35.5-96.5) for control, 46 (28-64.5) for silicone only, and 39.83(24-70) for verapamil-added silicone) (Kruskal-Wallis test, P < .05). On western blot, expression levels of collagen I protein was lower in the 1 mg/g and 10 mg/g verapamil-added silicone compared with control. Therefore, we suggest a therapeutic concentration of verapamil-added silicone gel of at least over 1 mg/g. Further study regarding maximally effective concentration and deeper insight into the mechanism of action should follow., (© 2021 The Authors. International Wound Journal published by Medicalhelplines.com Inc (3M) and John Wiley & Sons Ltd.)

Atomically thin transition metal dichalcogenides (TMDs) have recently attracted great attention since the unique and fascinating physical properties have been found in various TMDs, implying potential applications in next-generation devices. The progress towards developing new functional and high-performance devices based on TMDs, however, is limited by the difficulty in producing large-area monolayer TMDs due to a lack of knowledge of the growth processes of monolayer TMDs. In this work, we have investigated the growth processes of monolayer WS2 crystals using a thermal chemical vapor deposition method, in which the growth conditions were adjusted in a systematic manner. It was found that, after forming WO3-WS2 core-shell nanoparticles as nucleation sites on a substrate, the growth of three-dimensional WS2 islands proceeds by ripening and crystallization processes. Lateral growth of monolayer WS2 crystals subsequently occurs by the surface diffusion process of adatoms toward the step edge of the three-dimensional WS2 islands. Our results provide understanding of the growth processes of monolayer WS2 by using chemical vapor deposition methods.

Background: Purulent musculoskeletal infections often require surgical debridement and drainage. However, when the infection is extensive or involving multiple layers of tissues, maintaining drainage of the involved spaces can be difficult, even with the application of vacuum-assisted closure (VAC) therapy. Wide exposure and aggressive debridement is often required for such cases, which in turn may complicate wound coverage., Methods: A retrospective review was performed for 16 patients with musculoskeletal infections treated surgically. The diagnosis for the patients consisted of necrotizing fasciitis, large soft tissue abscess, peri-hardware abscess, infected compartment syndrome, emphysematous osteomyelitis, and gas gangrene of diabetic foot. We minimized the incision and resection for debridement and drainage, and instead we placed multiple foam pieces between the tissues involved with VAC, to maintain drainage of the hidden spaces with negative pressure., Results: Infection was successfully controlled in all cases. The mean duration of VAC treatment was 16.1 days (range, 5-36) and the mean number of VAC changes was 5.1 (range, 1-13). Primary wound closure was achieved in 11 cases, while skin grafts were used to cover the remaining five cases, which consisted of necrotizing fasciitis, infected compartment syndrome, and diabetic foot gas gangrene. No complications specifically associated with VAC therapy were observed., Conclusions: VAC using multiple foam pieces for hidden space drainage appears to be effective for infection control. It is helpful for minimizing exposure and resection for drainage and debridement, although subsequent reduction of the necessity or the level of wound coverage should further be investigated.

Mechanically robust composite nanofibers (NFs) with enhanced magnetic properties were made from polyvinylidene fluoride (PVDF) and Fe 3 O 4 nanoparticles (NPs) by an electrospinning method. At up to 11.3 wt %, Fe 3 O 4 NPs were embedded randomly in the PVDF NFs, but when the content exceeded 17 wt %, the NPs aggregated on the NF surfaces. Magnetization of the composite NFs consistently increased with the increasing Fe 3 O 4 NP content. The mechanical strength of the Fe 3 O 4 NP/PVDF composite NF was enhanced by a dispersion strengthening mechanism. A triboelectric nanogenerator was made from the composite, which showed enhanced output performance with the Fe 3 O 4 NP content less than 11.3 wt %, but the performance degraded at higher content. These results were attributed to the electret doping effect and surface aggregation of the Fe 3 O 4 NPs on the NFs, respectively.

Background: A contralateral normal hip joint has been often used as a reference standard in preoperative planning and intraoperative assessment of hip arthroplasty, with the assumption that bilateral hip joint geometries have no significant differences. However, one previous study using analog measurements on hardcopy films reported significant bilateral variation in hip joint geometry. We therefore investigated the level of agreement between the right and left hips for each measurement and determined index values and the range of normal bilateral variations., Methods: We assessed 100 standard anteroposterior radiographs of the pelvis in this study. Two independent observers measured the actual value of femoral head diameter, location of the femoral head center, acetabular offset, femoral offset, hip offset, greater trochanteric height, neck-shaft angle, medullary canal diameter, and proximal femoral diameter. Intraclass correlation coefficients (ICCs) and values of mean difference were calculated for each measurement., Results: The results demonstrated perfect agreement (ICC >0.8) between the right and left hips for most parameters and substantial agreement for greater trochanteric height (ICC = 0.735) and femoral offset (ICC = 0.773). The mean difference and standard deviation in the measurement between the right and left hips for the location of the femoral head center and the acetabular offset were 0.60 ± 0.48 mm and 0.42 ± 0.30 mm, respectively., Conclusion: Hip joint geometry is not influenced by side. In hip arthroplasty, a contralateral normal hip can be reliably used as a guide for preoperative planning using measurement tools on a picture archiving and communication system., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: Postsurgical adhesion formation is a concern in every field of surgery. We evaluated the efficacy of hyaluronic acid/sodium alginate-based microparticle anti-adhesive agents (MP) for the prevention of postsurgical adhesion formation in a standardized rabbit model., Method: To evaluate the anti-adhesion effect, a uterus-abdominal wall abrasion model was created in rabbits. On the surface of the injured uterus, an anti-adhesive agent, Interceed(®) or MP, was applied (positive control and study groups, respectively; n = 10 each). In another group of 10 animals, neither agent was applied (negative control group). The adhesion levels were graded 3 weeks after surgery. Acute and chronic toxicity was also evaluated., Results: The grade of adhesion was significantly lower in the MP group than in the negative control and positive control groups. No evidence of acute or chronic toxicity induced by this material was found in blood and tissue analysis., Conclusion: MP shows potential as an effective novel type of resorbable biomaterial to reduce postoperative adhesion. The easy placement and handling of this material make the MP powder attractive as a tissue adhesion barrier.

In this study, we have fabricated and characterized the silicon [Si] wire solar cells with conformal ZnO nanorod antireflection coating [ARC] grown on a Al-doped ZnO [AZO] seed layer. Vertically aligned Si wire arrays were fabricated by electrochemical etching and, the p-n junction was prepared by spin-on dopant diffusion method. Hydrothermal growth of the ZnO nanorods was followed by AZO film deposition on high aspect ratio Si microwire arrays by atomic layer deposition [ALD]. The introduction of an ALD-deposited AZO film on Si wire arrays not only helps to create the ZnO nanorod arrays, but also has a strong impact on the reduction of surface recombination. The reflectance spectra show that ZnO nanorods were used as an efficient ARC to enhance light absorption by multiple scattering. Also, from the current-voltage results, we found that the combination of the AZO film and ZnO nanorods on Si wire solar cells leads to an increased power conversion efficiency by more than 27% compared to the cells without it.

Visible light-emitting Ce-doped ZnO nanorods [NRs] without a post thermal annealing process were grown by hydrothermal method on a Si (100) substrate at a low temperature of 90°C. The structural investigations of Ce-doped ZnO NRs showed that the Ce3+ ions were successfully incorporated into the ZnO lattice sites without forming unwanted Ce-related compounds or precipitates. The optical investigation by photoluminescence spectra shows that the doped Ce3+ ions in the ZnO NRs act as an efficient luminescence center at 540 nm which corresponds to the optical transition of 5d → 4f orbitals in the Ce3+ ions. The photoluminescence intensity of the Ce-doped ZnO NRs increased with the increasing content of the Ce-doping agent because the energy transfer of the excited electrons in ZnO to the Ce3+ ions would be enhanced by increased Ce3+ ions.

To develop a targeted drug delivery system for cancer therapy and anti-angiogenesis, amphiphilic heparin bioconjugates were synthesized by chemical conjugation of hydrophobic retinoic acid and a targeting ligand, folic acid, to the heparin backbone (HFR). The chemical structure of the HFR conjugates was confirmed by proton nuclear magnetic resonance ((1)H NMR). Various HFR conjugates with different retinoic acid coupling ratios were obtained by modulating the retinoic acid feed molar ratio. The anticoagulant activity of the HFR conjugates decreased to 30% of heparin levels as measured by anti-FXa chromogenic assay. The bioconjugates retained the anti-angiogenic effect, showing a significant decrease in endothelial tubular formation using a Matrigel model. In aqueous solutions, the bioconjugates readily self-assembled to form nanoparticles via the hydrophobic interaction among retinoic acid. The HFR nanoparticles were spherical and ranged from 150 to 300 nm, depending on the degree of retinoic acid coupling. The presence of folic acid efficiently enhanced the cellular uptake of the HFR nanoparticles in folate receptor-positive cells. Furthermore, the internalized HFR nanoparticles demonstrated greater cytotoxicity against folate receptor-positive cells compared to free retinoic acid. These results indicate that specific delivery of retinoic acid with ternary biomolecular nanoparticles targeting folate receptor-positive tumors is a promising strategy to enhance chemotherapy efficacy with minimal side effects., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

The authors devised a novel biphasic scaffold combining hyaluronic acid and atelocollagen for the chondral phase and combining hydroxyapatite (HA) and beta-tricalcium phosphate (beta-TCP) for the osseous phase. The biphasic scaffold was fabricated by placing the freeze-dried chondral phase over the HA/beta-TCP scaffold prewetted with hyaluronate/atelocollagen solution. Chondrocytes were isolated in 28 rabbits, expanded, injected inside the chondral phase of the biphasic scaffold, and then cultured in chondrogenic medium. After 2 weeks of in vitro culture, chondrocytes had evenly infiltrated inside the chondral phase and produced extracellular matrix. For in vivo study, a large osteochondral defect was made on the patellar groove of the right distal femur and managed using one of the following methods: filling with cell-biphasic scaffold composite (group I); implanting only biphasic scaffold (group II); placing the removed osteochondral fragments back into the defect (group III, positive control); leaving empty (group IV, negative control). Seven rabbits were allocated to each group. After 12 weeks, the International Cartilage Repair Society Macroscopic Score was highest in group III, followed by group I, group II, and lastly group IV. Depression of the defect was greatest in group IV. There were three rabbits (two in group I and one in group II) that were completely denuded of the chondral phase. The junction to adjacent native cartilage was distinct in rabbits of all groups. The International Cartilage Repair Society Visual Histological Score was highest in group III, followed by groups II and I, and lastly group IV. In conclusion, our results suggest that a biphasic osteochondral composite using a chondral phase consisting of hyaluronate and atelocollagen and an osseous phase consisting of HA and beta-TCP holds the promise for repair of osteochondral defects.

Polycaprolactone (PCL) cylindrical scaffolds with gradually increasing pore size along the longitudinal direction were fabricated by a novel centrifugation method to investigate pore size effect on cell and tissue interactions. The scaffold was fabricated by the centrifugation of a cylindrical mold containing fibril-like PCL and the following fibril bonding by heat treatment. The scaffold showed gradually increasing pore size (from approximately 88 to approximately 405 microm) and porosity (from approximately 80% to approximately 94%) along the cylindrical axis by applying the centrifugal speed, 3000 rpm. The scaffold sections were examined for their in vitro cell interactions using different kinds of cells (chondrocytes, osteoblasts, and fibroblasts) and in vivo tissue interactions using a rabbit model (skull bone defects) in terms of scaffold pore sizes. It was observed that different kinds of cells and bone tissue were shown to have different pore size ranges in the scaffold for effective cell growth and tissue regeneration. The scaffold section with 380-405 microm pore size showed better cell growth for chondrocytes and osteoblasts, while the scaffold section with 186-200 microm pore size was better for fibroblasts growth. Also the scaffold section with 290-310 microm pore size showed faster new bone formation than those of other pore sizes. The pore size gradient scaffolds fabricated by the centrifugation method can be a good tool for the systematic studies of the interactions between cells or tissues and scaffolds with different pore size.

Macroenzymes are normal enzymes complexed with an immunoglobulin (usually IgG, rarely IgA or IgM). A number of macroenzymes have been reported in the literature. Among them, macro-AST has been detected in diseases such as acute and chronic hepatitis, various malignancies and autoimmune diseases, but usually not associated with any specific disease. We report a case of elevated AST activity in serum due to marco-AST formation in a female with chronic hepatitis C which was confirmed by AST isoenzyme electrophoresis. To our knowledge, this is the first report of macro-AST occurred in chronic hepatitis patient in Korea.