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Highlights: Flash-induced porous graphene (FPG) was synthesized via a broad-spectrum flash lamp that induced synergistic photo-effects between ultraviolet and visible-near-infrared wavelengths, resulting in large-area synthesis in just a few milliseconds. A hollow pillar graphene with low sheet resistance of 18 Ω sq−1 was produced, exhibiting low density (0.0354 g cm−3) and outstanding absolute electromagnetic interference shielding effectiveness of 1.12 × 105 dB cm2 g−1. A lightweight, flexible, and high-throughput FPG is applied for electromagnetic interference shielding of a drone radar system and the human body. Porous 2D materials with high conductivity and large surface area have been proposed for potential electromagnetic interference (EMI) shielding materials in future mobility and wearable applications to prevent signal noise, transmission inaccuracy, system malfunction, and health hazards. Here, we report on the synthesis of lightweight and flexible flash-induced porous graphene (FPG) with excellent EMI shielding performance. The broad spectrum of pulsed flashlight induces photo-chemical and photo-thermal reactions in polyimide films, forming 5 × 10 cm2-size porous graphene with a hollow pillar structure in a few milliseconds. The resulting material demonstrated low density (0.0354 g cm−3) and outstanding absolute EMI shielding effectiveness of 1.12 × 105 dB cm2 g−1. The FPG was characterized via thorough material analyses, and its mechanical durability and flexibility were confirmed by a bending cycle test. Finally, the FPG was utilized in drone and wearable applications, showing effective EMI shielding performance for internal/external EMI in a drone radar system and reducing the specific absorption rate in the human body. [ABSTRACT FROM AUTHOR]

Conductive metal-organic framework (C-MOF) thin-films have a wide variety of potential applications in the field of electronics, sensors, and energy devices. The immobilization of various functional species within the pores of C-MOFs can further improve the performance and extend the potential applications of C-MOFs thin films. However, developing facile and scalable synthesis of high quality ultra-thin C-MOFs while simultaneously immobilizing functional species within the MOF pores remains challenging. Here, we develop microfluidic channel-embedded solution-shearing (MiCS) for ultra-fast (≤5 mm/s) and large-area synthesis of high quality nanocatalyst-embedded C-MOF thin films with thickness controllability down to tens of nanometers. The MiCS method synthesizes nanoscopic catalyst-embedded C-MOF particles within the microfluidic channels, and simultaneously grows catalyst-embedded C-MOF thin-film uniformly over a large area using solution shearing. The thin film displays high nitrogen dioxide (NO2) sensing properties at room temperature in air amongst two-dimensional materials, owing to the high surface area and porosity of the ultra-thin C-MOFs, and the catalytic activity of the nanoscopic catalysts embedded in the C-MOFs. Therefore, our method, i.e. MiCS, can provide an efficient way to fabricate highly active and conductive porous materials for various applications. The immobilization of catalysts within the pores of conductive metal-organic frameworks (C-MOFs) via facile and scalable methodologies remains challenging. Here the authors report a microfluidic channel-embedded solution shearing process that enables the high throughput, large-area, single-step preparation of Pt nanocatalyst-embedded C-MOF thin films. [ABSTRACT FROM AUTHOR]

LiNi0.5Mn1.5O4 thin films were coated on stainless steel substrates by radio-frequency sputtering at room temperature for a lithium-ion battery. The cathode films were post-annealed at 500, 600 and 700 °C to study (i) the impact of annealing temperature on the crystallization of the cathode film and (ii) the reactivity between the cathode film and the stainless steel substrate. X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy were adopted to characterize the thin films. The electrochemical properties of the LiNi0.5Mn1.5O4 cathodes were investigated with cyclic voltammetry and galvanostatic charge/discharge tests. As the annealing temperature increased from 500 to 600 °C, the crystallinity and electrochemical characteristics of LiNi0.5Mn1.5O4 both improved. However, as the annealing temperature further increased to 700 °C, the phase purity and the electrochemical performance were greatly deteriorated. Combined chemical analyses with time-of-flight secondary ion mass spectrometry depth profiling and energy-dispersive X-ray spectroscopy in scanning transmission electron microscopy mapping have indicated that the cross-diffusion of metal ions between LiNi0.5Mn1.5O4 and the stainless steel substrate takes place at a temperature higher than 600 °C, which was attributed as a main origin of the phase change in the LiNi0.5Mn1.5O4 cathode layer and electrochemistry degradations of lithium-ion battery. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the yield and quality characteristics of red bean sprouts of three cultivars (Arari, Geomguseul, and Chungju) soaked in water for 0, 6, 12 or 24 h. The sprout yields of 'Arari' and 'Geomguseul' on day 7 were highest with the seeds soaked for 12 h. For 'Chungju', the yields from the seeds soaked for 12 and 24 h were not significantly (p > 0.05) different. Longer hypocotyls and shorter roots, which are also desirable characteristics of good sprouts, were also found in the sprouts with 12 h of seed soaking. The amounts of total minerals, thiamine, total free amino acids, and total phenols and DPPH radical scavenging potential of sprouts of all cultivars were higher than those of their seeds. This study showed that higher yield and better quality of red bean sprouts could be obtained with the seeds soaked for 12 h. [ABSTRACT FROM AUTHOR]

The objective of this study was to prepare low-alcoholic takju. Low-alcohol (3.06%) and dealcoholized (0.04–0.28%) takju samples were prepared by adopting bentonite clarification, heat and reverse osmosis treatments. The dealcoholization of takju, in most cases, significantly (p < 0.05) reduced the total mineral (from 505.80 to 258.61 mg/L), free amino acid (from 989.81 to 293.58 mg/mL), antioxidant potentials and total phenolic (from 345.30 to 156.30 µg GAE/mL) contents remained in the control to RO-3 (takju sample obtained from 3-time reverse osmosis and heat treatment). Similarly, the content of volatile compounds was also significantly (p < 0.05) decreased with the dealcoholization treatments. The finding of this study clearly showed that dealcoholized takju could be prepared but at the expense of reduced nutritional and antioxidant potentials. This study could be an exemplary in promoting traditional beverages in different countries by producing low or alcohol-free drinks. [ABSTRACT FROM AUTHOR]

Due to the negative consequences of synthetic herbicides use and their reducing effectiveness due to development of resistant weeds, promotion of eco-friendly weed management approaches is emphasized. Weed suppression by intercropping is basically attributed to increasing competition between the crop plants and weeds and/or the allelopathy effect of some crop plants. The effect of root extracts of maize or soybean on beggarticks and goosegrass weeds, as well as the effect of sole cropping of corn or soybean on weed occurrence and growth were investigated. The germination and seedling vigor of the two weeds were significantly (P < 0.05) inhibited with the maize root extract compared to those with soybean. Similarly, 420.52% low amount of fresh weeds was collected from the maize-grown pots (37.03 g) compared to that of the soybean-grown pots (155.72 g). The results of this study revealed that intercropping of soybean with maize could be an effective option to reduce the weed problem although comprehensive field studies are necessary for practical applications. [ABSTRACT FROM AUTHOR]

Peanut sprouts are gaining increasing popularity as a potential source of functional food. The objective of this study was to investigate yield and food value of peanut sprouts of six Korean peanut genotypes (Daekwang, Akwang, Baekjung, Alogi, Pungan and Heugttangkong) from day 5 through 9. Functional compounds like polyphenol, flavonoid, and resveratrol contents were significantly (p < 0.05) high in the sprouts compared to those in the seeds. Pungan yielded significantly (p < 0.05) high sprouts followed by Alogi. However, antioxidant potentials and functional compounds in the sprouts varied significantly (p < 0.05) with genotype, sprout part, and day after germination. Overall consideration of the yield, functional compounds, and antioxidant potentials of the sprouts suggested that more appropriate time of sprout harvest for Alogi and Pungan was day 5-7 and that for the other genotypes was day 5-8. The yield and functional properties of peanut sprouts significantly varied with genotypes, parts, and age. [ABSTRACT FROM AUTHOR]

Various adjuncts, including fruits, are added for flavoring beer, one of the most famous beverages in the world. The influence of persimmon fruit on antioxidant activities and quality characteristics of beer was investigated in this study. The antioxidant activities measured through DPPH and superoxide and hydroxyl anions scavenging potentials as well as total polyphenol contents of the persimmon-treated beer were significantly (p < 0.05) high compared to the control. The mineral elements Mg, K, and Ca were also significantly (p < 0.05) increased, however toxic heavy metals were not detected in the persimmon beer. Among the persimmon beer samples, the overall acceptance value was significantly (p < 0.05) high when the beer was prepared by adding 150 g of the fruit in 10 L of water. The results suggested that an addition of 150 g of persimmon fruit per 10 L of water could better enrich the nutritional, organoleptic, and antioxidant potentials of beer. [ABSTRACT FROM AUTHOR]

Abstract: This study was carried out to determine the effect of different concentrations of Bacillus subtilis (0, 1, 3, 5, and 7%) on the antioxidant potential and biochemical constituents of traditional Korean fermented soybean, Cheonggukjang (CKJ). The antioxidant capacity was studied using the reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) assays and the total phenolic contents (TPC) were measured using the Folin-Ciocalteu method. CKJ prepared using 1% B. subtilis revealed the highest TPC (5.99 mg/g), total amino acids (7.43 mg/g), DPPH (94.24%), and ABTS (86.03%) radical-scavenging activity and had the highest value of palmitic acid (11.65%), stearic acid (2.87%), and linolenic acid (11.76%). Results showed that the calcium, iron, sodium, and zinc contents increased in the CKJ prepared using 7% B. subtilis from 1481.38 to 1667.32, 41.38 to 317.00, 48.01 to 310.07, and 32.82 to 37.18 mg/kg respectively. In conclusion, the present results indicate that the fermentation of soybean with B. subtilis (KCTC 13241) significantly augments the nutritional and antioxidant potential of CKJ and it can be recommended as a health-promoting food source. [ABSTRACT FROM AUTHOR]

It has been reported that the innate immune response plays important roles in brain ischemia and that the infiltration of blood-derived immune cells is a key initiator of this response. Nerve injury-induced protein 1 (Ninjurin 1, Ninj1) is a cell adhesion molecule responsible for cell-to-cell interactions between immune cells and endothelial cells. In the present study, we investigated the proinflammatory and neuroprotective effects of Ninj1 and a dodecamer peptide harboring Ninj1 N-terminal adhesion motif (N-NAM, Pro26~Asn37) in a rat middle cerebral artery occlusion (MCAO) model of stroke. Ninj1 was predominantly induced in neutrophils and endothelial cells in the ischemic hemispheres around 12 h to 1 day post-MCAO, which coincided with a massive neutrophil influx. We demonstrated that intranasal administration of Ninj1 small interfering RNA (siRNA) or N-NAM significantly blocked neutrophil infiltration in postischemic brains. In addition, intranasal administration of Ninj1 siRNA or N-NAM reduced the mean infarct volume to 46.5 ± 9.2 or 30.6 ± 11.7% of that of the PBS-treated MCAO controls, respectively, which was accompanied by significant amelioration of neurological and motor deficits. We showed that N-NAM or Ninj1 siRNA effectively blocked the adhesion and transendothelial migration of TNF-α-stimulated human myelocytic leukemia cells to human umbilical vein endothelial cells and similarly suppressed adhesion and migration of monocytes. Activations of phosphoinositide 3-kinase and Ras-related C3 botulinum toxin substrate 1 are involved in these Ninj1-mediated processes and can be inhibited by N-NAM or Ninj1 siRNA. These results indicate that Ninj1 plays an important role in neutrophil infiltration in the postischemic brain and N-NAM confers robust neuroprotective and anti-inflammatory effects by inhibiting Ninj1-mediated infiltration of neutrophils. [ABSTRACT FROM AUTHOR]

Abstract: Two-dimensional (2D) nanostructures are gaining tremendous interests due to the fascinating physical, chemical, electrical, and optical properties. Recent advances in 2D nanomaterials synthesis have contributed to optimization of various parameters such as physical dimension and chemical structure for specific applications. In particular, development of high performance gas sensors is gaining vast importance for real-time and on-site environmental monitoring by detection of hazardous chemical species. In this review, we comprehensively report recent achievements of 2D nanostructured materials for chemiresistive-type gas sensors. Firstly, the basic sensing mechanism is described based on charge transfer behavior between gas species and 2D nanomaterials. Secondly, diverse synthesis strategies and characteristic gas sensing properties of 2D nanostructures such as graphene, metal oxides, transition metal dichalcogenides (TMDs), metal organic frameworks (MOFs), phosphorus, and MXenes are presented. In addition, recent trends in synthesis of 2D heterostructures by integrating two different types of 2D nanomaterials and their gas sensing properties are discussed. Finally, this review provides perspectives and future research directions for gas sensor technology using various 2D nanomaterials.Graphical Abstract: [ABSTRACT FROM AUTHOR]

4-Hydroxybenzyl alcohol (4-HBA) is an important phenolic constituent of Gastrodia elata (GE) Blume, which is used as a traditional herbal medicine in East Asia. Many activities have been reported to underlie the beneficial effects of 4-HBA in brain, such as, anti-oxidative, anti-inflammatory, anti-excitotoxic, and anti-apoptotic effects in neurons and microglia. Here, the authors demonstrate the robust neuroprotective effects of 4-HBA in rat middle cerebral artery occlusion (MCAO) model of stroke, and showed anti-Zn2+ toxicity in neurons and astrocytes as a molecular mechanism contributing to these effects. Intraperitoneal administration of 4-HBA (20 mg/kg) in Sprague-Dawley rats 1 h after MCAO reduced infarct volumes to 27.1 ± 9.2% of that of MCAO controls and significantly ameliorated motor impairments and neurological deficits. Significant suppressions of Zn2+-induced cell death, ROS generation, and PARP-1 induction by 4-HBA were observed in primary cortical cultures. 4-HBA also protected astrocytes from Zn2+-induced toxicity and suppressing ROS generation by employing slightly different molecular mechanisms, i.e., suppressing PARP-1 induction and NAD depletion under acute Zn2+-treatment and suppressing p67 NADPH oxidase subunit induction under chronic Zn2+-treatment. Results indicate that the protective effects of 4-HBA against Zn2+-toxicity in neurons and astrocytes contribute to its robust neuroprotective effects in the postischemic brain. Considering the pleiotropic effects of 4-HBA, which have been reported in previous reports and added in the present study, it has therapeutic potential for the amelioration of ischemic brain damage. [ABSTRACT FROM AUTHOR]

We report photoelectrochemical hydrogen evolution reaction using a CuO-based photocathode with a layer doped with Zn ions. The doping results in the shift of the onset flat-band potential of the photocathode, likely a consequence of maximized band-bending in the CuO/Zn : CuO heterojunction. Systematic electrochemical analysis reveals that expansion of depletion region is responsible for the enhanced photoelectrochemical performance, e.g., the increase of photocurrent and reduced internal resistance. [ABSTRACT FROM AUTHOR]

Takju, popularly known as makgeolli, is a famous traditional alcoholic beverage in Korea. Beneficial health effects of different traditional beverages have received attention among consumers and researchers. The influence of addition of blueberry and black rice powders to takju was investigated. Chemical characteristics, color values, DPPH radical scavenging activities, total phenolic contents, and sensory characteristics were evaluated. Addition of blueberry and black rice powders improved the antioxidant activity and the overall taste of takju. The optimum proportions of added blueberry and black rice powders were 0.249% and 0.004-0.049%, respectively. Addition of optimum amounts of blueberry and black rice powders enhanced the overall quality of the Korean traditional rice wine takju. [ABSTRACT FROM AUTHOR]

The flat panel display (FPD) market has been experiencing a rapid transition from liquid crystal (LC) to organic light emitting diode (OLED) displays, leading, in turn, to the accelerated commercialization of OLED televisions already in 2013. The major driving force for this rapid change was the adaptation of novel oxide semiconductor materials as the active channel layer in thin film transistors (TFTs). Since the report of amorphous-InGaZnO (a-IGZO) semiconductor materials in 2004, the FPD industry has accelerated the development of oxide TFTs for mass-production. In this review, we focus on recent progress in applying electro-ceramic materials for oxide-semiconductor thin-film-transistors. First, oxide-based semiconductor materials, distinguished by vacuum or solution processing, are discussed, with efforts to develop high-performance, cost-effective devices reviewed in chronological order. The introduction and role of high dielectric constant - reduced leakage gate insulators, in optimizing oxide-semiconductor device performance, are next covered. We conclude by discussing current issues impacting oxide-semiconductor TFTs, such as field effect mobility and device stability and the proposed directions being taken to address them. [ABSTRACT FROM AUTHOR]

Osteopontin (OPN) is a phosphorylated glycoprotein possessing an arginine-glycine-aspartate (RGD)-motif, which binds to several cell surface integrins and mediates a wide range of cellular processes. Inductions of OPN have been reported in the postischemic brain, and the neuroprotective effects of OPN have been demonstrated in animal models of stroke. In the present study, we showed a robust neuroprotective effect of RGD-containing icosamer OPN peptide (OPNpt20) in a rat model of focal cerebral ischemia (middle cerebral artery occlusion, MCAO). Intranasally administered OPNpt20 reduced mean infarct volume by 79.7 % compared to the treatment-naïve MCAO control animals and markedly ameliorated neurological deficits. In addition, OPNpt20 significantly suppressed the inductions of iNOS and of inflammatory markers in postischemic brains and in primary microglial cultures, demonstrating anti-inflammatory effects. Administration of a mutant peptide, in which RGD was replaced by arginine-alanine-alanine (RAA), failed to suppress infarct volumes in MCAO animals and co-administration of OPNpt20 with anti-αβ integrin antibody failed to suppress iNOS induction in primary microglia culture, indicating that the RGD motif in OPNpt20 and endogenous αβ integrin play critical roles. Furthermore, pull-down assay revealed a direct binding between OPNpt20 and αβ integrin in primary microglia culture. Together, these results indicate that RGD-containing OPN icosamer has therapeutic potential in the postischemic brain and αβ integrin-mediated anti-inflammatory effect might be an underlying mechanism. [ABSTRACT FROM AUTHOR]

As a leading cause of death and adult disability, ischemic stroke requires the development of non-invasive, long-acting treatments. Osteopontin (OPN) is an endogenous protein shown to have neuroprotective effects in the post-ischemic brain of rats when administered through the non-invasive, intranasal pathway. Previously, gelatin microspheres (GMSs) have been shown to enhance the neuroprotective effects of OPN when used as a carrier during instrastriatal administration, but GMSs are generally too large to enter the brain parenchyma following intranasal administration. Here, gelatin nanoparticles (GNPs) were investigated as a carrier for intranasal delivery of an OPN peptide for the treatment of ischemic stroke. We not only successfully fabricated GNPs with a uniform shape, but also demonstrated the ability of these GNPs to pass into the brain parenchyma following intranasal administration. Critically, the use of GNPs as a carrier allowed for a 71.57 % reduction in mean infarct volume and extended the therapeutic window of intranasally administered OPN peptide to at least 6 h post-middle cerebral artery occlusion (MCAO). Our findings support the development of GNPs as a promising drug delivery platform for the intranasal treatment of ischemic stroke and, potentially, other neurologic disorders. [ABSTRACT FROM AUTHOR]

Glycyrrhizin (GL), a triterpene present in the roots and rhizomes of licorice ( Glycyrrhiza glabra), has been shown to have anti-inflammatory and anti-viral effects. In our previous reports, we demonstrated the neuroprotective effects of GL in the postischemic brain and in kainic acid (KA)-induced seizure animal model. In this KA-induced seizure model, the systemic administration of GL 30 min before KA administration significantly suppressed neuronal cell death and markedly suppressed gliosis and proinflammatory marker inductions. In the present study, we showed that high-mobility group box 1 (HMGB1), an endogenous danger signal, was induced in hippocampal CA1 and CA3 regions of the same KA-induced model, and peaked at ~3 h and at 6 days post-KA. HMGB1 was transiently induced in neurons and astrocyte at 3 h post-KA, and it was released from dying neurons and accumulated in serum at 12 h post-KA. Furthermore, after ~4 days of almost undetectable levels in the hippocampus, delayed and marked HMGB1 induction was detected at 6 days post-KA, mainly in astrocytes and endothelial cells, in which HMGB1 was localized in nuclei, and not secreted into serum. Interestingly, GL suppressed HMGB1 inductions in hippocampus and also suppressed its release into serum in KA-treated mice. Since we established previously that GL has anti-inflammatory and anti-excitotoxic effects in this KA-induced seizure model, these results indicate that the neuroprotective effect of GL in the KA-injected mouse brain might be attributable to the inhibitions of HMGB1 induction and release, which in turn, mitigates the inflammatory process. [ABSTRACT FROM AUTHOR]

Phase and microstructural evolution of Sn-Carbon composite nanofibers (NFs) under various heat treatment conditions was clearly demonstrated in this work. Amorphous carbon nanofibers (a-CNFs) that contained metallic Sn nanoparticles were prepared via electrospinning and subsequent calcination under a reducing atmosphere. The sizes of the metallic Sn particles, which were decorated inside and outside of a-CNFs, were precisely manipulated by varying the Sn precursor content and introducing a reinforced quenching step, i.e., controlling the cooling rate after high-temperature processing. Because of the low melting temperature of metallic Sn (231.9 °C), the nucleation and growth rates of the Sn nanoparticles were significantly influenced by the high-temperature processing and cooling condition. In particular, the stresses that originated from volume changes of the Sn nanoparticles during the lithium alloying and dealloying processes were effectively compensated by amorphous carbon containing Sn particles, which led to reduced structural damage. The morphologies of the fibers with incorporated Sn nanoparticles provided efficient permeability to allow the penetration of the electrolyte into the inner fiber structure while maintaining a high-capacity (950 mAh g at 0.5 C-rate) characteristics due to enhanced surface activity. [ABSTRACT FROM AUTHOR]

This work presents a simple synthetic route to produce WO nanofibers functionalized by catalytic Pt and IrO nanoparticles and their superior acetone and HS sensing characteristics, demonstrating the potential use of Pt and IrO nanoparticles in applications as sensors of biomarkers of diabetes and halitosis, respectively, in exhaled breath. The individual WO fiber, calcined at 500 °C, was composed of small nanoparticles with a size distribution in the range of 30-100 nm. Networks of WO fibers exhibited a high surface-to-volume ratio and unique morphologies, thus facilitating efficient gas transport into the entire fiber layers. Pt (4-7 nm) and Ir (4-8 nm) nanoparticles were synthesized by polyol methods and were used as additives to decorate the surface of the WO fibers. After a heat treatment, those catalyst particles were partially or fully oxidized to Pt/PtO and IrO, respectively. To investigate the advantages of Pt-decorated WO fibers (Pt-WO) and IrO-decorated WO (IrO-WO) fibers as acetone (CHCOCH) and HS sensing materials, respectively, we carried out gas-sensing measurements in a highly humid atmosphere (RH 75 %) similar to that of an oral cavity. The Pt-WO fibers showed a high acetone response (R/R = 8.7 at 5 ppm) at 350 °C and a superior HS response (R/R = 166.8 at 5 ppm) at 350 °C. Interestingly, IrO-WO fibers showed no response to acetone, while the gas response to HS exhibited temperature-insensitivity, which has never been reported in any other work. Thus, the highly selective cross-response between HS and acetone was successfully achieved via the combination of IrO particles on WO fibers. This work demonstrates that accurate diagnosis of diabetes and halitosis by sensing exhaled breath can be realized through the use of electrospun WO fibers decorated with Pt and IrO catalysts. [ABSTRACT FROM AUTHOR]

SnO nanofiber mats fabricated through electrospinning followed by thermo-compression and subsequent calcination steps exhibited unique morphologies facilitating efficient gas transport into the layers combined with high surface area (∼73.5 m/g, measured by BET) and small grain size (∼5-15 nm), which are well suited for ultrasensitive gas detection. Single SnO nanofibers were found to have a belt-like structure of closely packed nanocrystallites, facilitating excellent adhesion to the substrate and good electrical contact to the electrodes. I-V measurements of single SnO nanofibers displayed ohmic behavior with electrical conductivity of 1.5 S/cm. Gas sensor prototypes comprising a random network of SnO fibers exhibited high sensitivity when exposed to NO at 225°C and CO at 300°C. A detection limit of 150 ppb NO at 185°C was estimated by extrapolating the sensitivity results obtained on exposure to higher gas concentrations, demonstrating potential of achieving ultra-sensitive gas detection at low operating temperatures enabled by the present synthesis method. [ABSTRACT FROM AUTHOR]

A novel NiO/MnO2 pompon-like hybrid structure was synthesized through a facile one-step hydrothermal in situ growth approach in this paper. NiO nanosheets grow on MnO2 pompon-like microsphere to form typical hybrid structures which significantly increase the abundant active sites of electrode materials. The resulting NiO/MnO2 electrode material exhibits an impressive specific capacity of 2706.1 F/g at a current density of 1 A/g. Remarkably, NiO/MnO2 pompon-like hybrid structure shows excellent cycling performance and its capacity retention is maintained at 84.8% and the charge–discharge efficiency at 96% after 15,000 cycles. Even after undergoing 40,000 cycles, the electrode material maintains an outstanding charge–discharge efficiency of 95.2% with capacity retention of 69%, which revealing promising application as long-term electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Cobalt oxide that has high energy density, is the next-generation candidate as the anode material for LIBs. However, the practical use of Co3O4 as anode material has been hindered by limitations, especially, low electrical conductivity and pulverization from large volume change upon cycling. These features lead to hindrance to its electrochemical properties for lithium-ion batteries. To improve electrochemical properties, we synthesized one-dimensional (1-D) Co3O4 nanofibers (NFs) overed with reduced graphene oxide (rGO) sheets by electrostatic self-assembly (Co3O4 NFs@rGO). The flexible graphene oxide sheets not only prevent volume changes of active materials upon cycling as a clamping layer but also provide efficient electrical pathways by three-dimensional (3-D) network architecture. When applied as an anode for LIBs, the Co3O4 NFs@rGO exhibits superior electrochemical performance: (i) high reversible capacity (615 mAh g−1 and 92% capacity retention after 400 cycles at 4.0 A g−1) and (ii) excellent rate capability. Herein, we highlighted that the enhanced conversion reaction of the Co3O4 NFs@rGO is attributed to effective combination of 1-D nanostructure and low content of rGO (~3.5 wt%) in hybrid composite. [ABSTRACT FROM AUTHOR]

Alloys are recently receiving considerable attention in the community of rechargeable batteries as possible alternatives to carbonaceous negative electrodes; however, challenges remain for the practical utilization of these materials. Herein, we report the synthesis of germanium-zinc alloy nanofibers through electrospinning and a subsequent calcination step. Evidenced by in situ transmission electron microscopy and electrochemical impedance spectroscopy characterizations, this one-dimensional design possesses unique structures. Both germanium and zinc atoms are homogenously distributed allowing for outstanding electronic conductivity and high available capacity for lithium storage. The as-prepared materials present high rate capability (capacity of ~ 50% at 20 C compared to that at 0.2 C-rate) and cycle retention (73% at 3.0 C-rate) with a retaining capacity of 546 mAh g−1 even after 1000 cycles. When assembled in a full cell, high energy density can be maintained during 400 cycles, which indicates that the current material has the potential to be used in a large-scale energy storage system. Alloy anode materials are receiving renewed interest. Here the authors show the design of Ge-Zn nanofibers for lithium ion batteries. Featured by a homogeneous composition at the atomic level and other favorable structural attributes, the materials allow for impressive electrochemical performance. [ABSTRACT FROM AUTHOR]

To achieve the rational design of nanostructures for superior gas sensors, the ultrasmall nanoparticles (NPs) loaded on ternary metal oxide (TMO) hollow spheres (HS) were synthesized by using the polystyrene (PS) sphere template and bimetallic metal-organic framework (BM-MOFs) mold. The zinc and cobalt based zeolite imidazole frameworks (BM-ZIFs) encapsulating ultrasmall Pd NPs (2-3 nm) were assembled on PS spheres at room temperature. After calcination at 450 °C, these nanoscale Pd particles were effectively infiltrated on the surface of ZnO/ZnCo2O4 HSs. In addition, the heterojunctions of Pd-ZnO, Pd-ZnCo2O4, and ZnO-ZnCo2O4 were formed on each phase. The synthesized Pd-ZnO/ZnCo2O4 HSs exhibited extremely high selectivity toward acetone gas with notable sensitivity (S = 69% to 5 ppm at 250 °C). The results demonstrate that MOF driven ultrasmall catalyst loaded TMO HSs were highly effective platform for high performance chemical gas sensors. [ABSTRACT FROM AUTHOR]

Ethyl pyruvate (EP) is a simple aliphatic ester of pyruvic acid and has been shown to have robust neuroprotective effects via its anti-inflammatory, anti-oxidative, and anti-apoptotic functions. In an effort to develop novel EP derivatives with greater protective potencies than EP, we generated four EP isosteres, among them the neuroprotective potency of N,N-diethyl-2-oxopropanamide (DEOPA), in which the ethoxy group of EP was replaced with diethylamine, was far greater than that of EP. When DEOPA was administered intravenously (5 mg/kg) to rat middle cerebral artery occlusion (MCAO) model at 6 hrs post-surgery, it suppressed infarct formation, ameliorated neurological and sensory/motor deficits, and inhibited microglial activation and neutrophil infiltrations in the postischemic brain more effectively than EP. In particular, DEOPA markedly suppressed LPS-induced nitrite production and cytokine/chemokine inductions in microglia, neutrophils, and endothelial cells and these effects are attributable to inhibition of the activity of NF-κB by suppressing IκB-α degradation and p65 to DNA binding. In addition, DEOPA suppressed NMDA-induced neuronal cell death in primary cortical neuron cultures by NAD replenishment and suppression of NF-κB activity. Together, these results indicate DEOPA has multi-modal protective effects against ischemic brain damage targeting numerous cell types in the brain and also against other inflammation-related diseases. [ABSTRACT FROM AUTHOR]

Drugs are currently being developed to attenuate oxidative stress as a treatment for brain injuries. C-phycocyanin (C-Pc) is an antioxidant protein of green microalgae known to exert neuroprotective effects against oxidative brain injury. Astrocytes, which compose many portions of the brain, exert various functions to overcome oxidative stress; however, little is known about how C-Pc mediates the antioxidative effects of astrocytes. In this study, we revealed that C-Pc intranasal administration to the middle cerebral artery occlusion (MCAO) rats ensures neuroprotection of ischemic brain by reducing infarct size and improving behavioral deficits. C-Pc also enhanced viability and proliferation but attenuated apoptosis and reactive oxygen species (ROS) of oxidized astrocytes, without cytotoxicity to normal astrocytes and neurons. To elucidate how C-Pc leads astrocytes to enhance neuroprotection and repair of ischemia brain, we firstly developed 3D oxidized astrocyte model. C-Pc had astrocytes upregulate antioxidant enzymes such as SOD and catalase and neurotrophic factors BDNF and NGF, while alleviating inflammatory factors IL-6 and IL-1β and glial scar. Additionally, C-Pc improved viability of 3D oxidized neurons. In summary, C-Pc was concluded to activate oxidized astrocytes to protect and repair the ischemic brain with the combinatorial effects of improved antioxidative, neurotrophic, and anti-inflammatory mechanisms. [ABSTRACT FROM AUTHOR]

Anatase TiO2 has been suggested as a potential sodium anode material, but the low electrical conductivity of TiO2 often limits the rate capability, resulting in poor electrochemical properties. To address this limitation, we propose graphene-wrapped anatase TiO2 nanofibers (rGO@TiO2 NFs) through an effective wrapping of reduced graphene oxide (rGO) sheets on electrospun TiO2 NFs. To provide strong electrostatic interaction between the graphene oxide (GO) sheets and the TiO2 NFs, poly(allylamine hydrochloride) (PAH) was used to induce a positively charged TiO2 surface by the immobilization of the -NH3+ group and to promote bonding with the negatively charged carboxylic acid (-COO−) and hydroxyl (-O−) groups on the GO. A sodium anode electrode using rGO@TiO2 NFs exhibited a significantly improved initial capacity of 217 mAh g−1, high capacity retention (85% after 200 cycles at 0.2C), and a high average Coulombic efficiency (99.7% from the second cycle to the 200th cycle), even at a 5C rate, compared to those of pristine TiO2 NFs. The improved electrochemical performances stem from highly conductive properties of the reduced GO which is effectively anchored to the TiO2 NFs. [ABSTRACT FROM AUTHOR]

Tailoring of semiconducting metal oxide nanostructures, which possess controlled pore size and concentration, is of great value to accurately detect various volatile organic compounds in exhaled breath, which act as potential biomarkers for many health conditions. In this work, we have developed a very simple and robust route for controlling both the size and distribution of spherical pores in electrospun WO3 nanofibers (NFs) via a sacrificial templating route using polystyrene colloids with different diameters (200 nm and 500 nm). A tentacle-like structure with randomly distributed pores on the surface of electrospun WO3 NFs were achieved, which exhibited improved surface area as well as porosity. Porous WO3 NFs with enhanced surface area exhibited high gas response (Rair/Rgas = 43.1 at 5 ppm) towards small and light H2S molecules. In contrast, porous WO3 NFs with maximized pore diameter showed a high response (Rair/Rgas = 2.8 at 5 ppm) towards large and heavy acetone molecules. Further enhanced sensing performance (Rair/Rgas = 65.6 at 5 ppm H2S) was achieved by functionalizing porous WO3 NFs with 0.1 wt% non-oxidized graphene (NOGR) flakes by forming a Schottky barrier (ΔΦ = 0.11) at the junction between the WO3 NFs (Φ = 4.56 eV) and NOGR flakes (Φ = 4.67 eV), which showed high potential for the diagnosis of halitosis. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses topics related to advance electronic materials and mentions the people who the editorial staff would like to thank for their contribution to the success of the special issue of the journal including Do-Kyun Kwon and Do Kyung Kim.

One of the emerging technologies of the recent times harboring nanotechnology to fabricate nanofibers for various biomedical and environmental applications are electrospinning (nanofiber technology). Their relative ease in use, simplicity, functionality and diversity has surpassed the pitfalls encountered with the conventional method of generating fibers. This review aims to provide an overview of electrospinning, principle, methods, feed materials, and applications toward tissue engineering. To begin with, evolution of electrospinning and its typical apparatus have been briefed. Simultaneously, discussion on the production of nanofibers with diversified feed materials such as polymers, small molecules, colloids, and nanoparticles and its transformation into a powerful technology has been dealt with. Further, highlights on the application of nanofibers in tissue engineering and the commercialized products developed using nanofiber technology have been summed up. With this rapidly emerging technology, there would be a great demand pertaining to scalability and environmental challenge toward tissue engineering applications. [ABSTRACT FROM AUTHOR]

The shells of three important food nuts, walnut, almond, and pine nut, were studied in view of valorization as residues. The shells differed chemically: walnut shells had 10.6% extractives, 30.1% lignin, and 49.7% polysaccharides; almond shells 5.7% extractives, 28.9% lignin, and 56.1% polysaccharides; and pine nut shells 4.5% extractives, 40.5% lignin, and 48.7% polysaccharides. The polysaccharide composition also differed, e.g., glucose/xylose ratio of 1.12, 0.94, and 2.29 for walnut, almond, and pine nut shells, respectively. Walnut and almond shells have a SG lignin (S/G 1.6 and 1.0, respectively) and pine nut shell a G lignin. The lipophilic extracts contained mostly saturated and unsaturated alkanoic acids. The ethanol-water extracts contained total phenolics, flavonoids, and condensed tannins. The antioxidant activity was moderate (IC50 15.2, 7.9, and 8.2 μg/mL for walnut, almond, and pine nut). The three nut shells fractured easily with little formation of fines. [ABSTRACT FROM AUTHOR]

LiMn2O4 thin films with three-dimensional (3D) structure were prepared by the sol–gel method. Polystyrene beads (300 nm) were dispersed in the form of monolayers on Pt/Ti/SiO2/Si substrates, which were then used as templates for fabricating three-dimensionally ordered electrodes. A coating solution prepared from acetylacetonate sources was dropped on the template-deposited substrates, which were then calcinated at 400 °C. The templates were removed by calcinations, and a 3D structure was formed through an annealing process. The discharge capacity of the 3D LiMn2O4 films was 1.63–3.03 μAh cm−2. The capacity loss over 100 cycles was approximately 18%, however, the 3D structure was not destroyed during cycling. [ABSTRACT FROM AUTHOR]