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Recent evidence has shown that the vascular endothelial growth factor (VEGF) system plays a crucial role in several neuropathological processes. We previously reported an upregulation of VEGF-C and its receptor, VEGFR-3, in reactive astrocytes after the onset of status epilepticus (SE). However, it remains unknown, which molecules act as downstream signals following VEGFR-3 upregulation, and are involved in reactive astrogliosis after SE. Therefore, we investigated whether VEGFR-3 upregulation within reactive astrocytes is associated with the activation of mammalian target of rapamycin (mTOR) signaling, which we confirmed by assaying for the phosphorylated form of S6 protein (pS6), and whether VEGFR-3-mediated mTOR activation induces astroglial glutamate transporter-1 (GLT-1) expression in the hippocampus after pilocarpine-induced SE. We found that spatiotemporal expression of pS6 was consistent with VEGFR-3 expression in the hippocampus after SE, and that both pS6 and VEGFR-3 were highly expressed in SE-induced reactive astrocytes. Treatment with the mTOR inhibitor rapamycin decreased astroglial VEGFR-3 expression and GLT-1 expression after SE. Treatment with a selective inhibitor for VEGFR-3 attenuated astroglial pS6 expression as well as suppressed GLT-1 expression and astroglial reactivity in the hippocampus after SE. These findings demonstrate that VEGFR-3-mediated mTOR activation could contribute to the regulation of GLT-1 expression in reactive astrocytes during the subacute phase of epilepsy. In conclusion, the present study suggests that VEGFR-3 upregulation in reactive astrocytes may play a role in preventing hyperexcitability induced by continued seizure activity.

The thermally insulating, fire-retardant, smokeless and flexible polymer nanofiber is an incredibly important material for mankind. This polymer nanofiber is expected to breed technological innovations in applications such as thermally insulated clothing and building materials. Here, we propose an electrospinning process to fabricate silica aerogel-filled polymer nanofibers by modifying the typical sol–gel chemistry process for the synthesis of silica aerogel. Silica aerogel-filled polyvinylidene fluoride (PVdF) nanofiber webs, fabricated using the proposed process, were fire-retardant, smokeless and flexible; they also exhibited a low thermal conductivity of 0.028 W·m−1·K−1, which was 26.3% lower than that of pure PVdF nanofiber webs. To study the unique thermal characteristics of nanofibers theoretically, a micromechanics-based, two-scale multiphase model was proposed, with consideration of fiber structure including nano and micro pores. These developments make an important contribution to bringing silica aerogel products to everyday life.

To evaluate the redox behavior of $${\text{VO}}^{2 + } / {\text{VO}}_{2}^{ + }$$ as a simulant of $${\text{NpO}}_{2}^{ + } / {\text{NpO}}_{2}^{2 + }$$ in boiling nitric acid solution, i.e., typical operating conditions for nuclear fuel reprocessing plants, oxidation rate measurements for VO2+ in boiling and non-boiling nitric acid solutions, thermodynamic calculations, and kinetic calculations were performed. The results indicated that the apparent oxidation rate of VO2+ to $${\text{VO}}_{2}^{ + }$$ is accelerated by a decrease in $${\text{NO}}_{2}^{ - }$$ and HNO2 concentrations owing to the boiling phenomena of nitric acid solution.

Adhesive materials for carbon fiber reinforced polymer (CFRP) composites have attracted the interest of researchers as an effective means to bond newly developed lightweight and high-performance composite structures. In this study, we developed a novel method to overcome these critical problems through a silica particle coating. Four-step bonding procedures were proposed to bind heterogeneous materials, where various concentrations of silica particles were introduced to coat CFRP composite surfaces uniformly in order to serve as a reinforcement and as a protection barrier layer against CFRP fractures. Experimental evaluations of the mechanics and fractography studies were conducted to clarify the correlations among the silica concentrations, adhesive strength levels, coating properties, and CFRP surface fractures. It was demonstrated that the introduction of the silica surface coating improves the adhesive strength by approximately 20% while also reducing CFRP surface fractures significantly by around 90%.

Electrophoresis can be an effective approach for depositing carbon nanotubes (CNTs) on the surface of carbon fiber (CF). Nevertheless, it has been rarely reported on polyphenylene sulfide (PPS) composites filled with CFs surface-modified by CNTs based on electrophoresis. In this study, we investigated the electrophoresis process conditions that can completely coat CF with multi-walled CNTs (MWCNTs) using self-manufactured electrophoresis equipment, and the enhancement of interfacial, electrical and flexural properties of PPS composites by introducing CFs coated with MWCNTs based on electrophoresis. In particular, interfacial shear strength (IFSS) of the PPS composites was measured by microbond tests and improved by about 41.7% due to the MWCNTs introduced on the surface of CFs. These enhancements were theoretically explained by an interface-modified CF-based micromechanical model. Introducing MWCNTs on the CF surface based on electrophoresis was demonstrated to be an effective method for improving the interfacial, electrical and flexural properties of PPS composites.

To separate heat-generating Cs from high-level liquid waste (HLLW), the extraction of Cs(I) using 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (calix[4]arene-R14) in combination with 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) ionic liquids ([C n mim][NTf2], where n = 2, 4, and 6) was investigated. Under moderately acidic conditions, the calix[4]arene-R14/[C n mim][NTf2] system showed a higher extraction efficiency (ECs) than that exhibited by the conventional calix[4]arene-R14/dichloromethane system. All extraction processes reached equilibrium within 5 min. Slope analysis revealed that the Cs:calix[4]arene-R14 inclusion complex has a 1:1 stoichiometry. The extraction was found to be exothermic and influenced by the presence of Na(I). These extraction systems exhibited high efficiency and selectivity for Cs(I) in simulated HLLW.

To separate Mo(VI) from high-level liquid waste, a silica-based (anti-DEHDO + Dodec)/SiO2-P adsorbent was synthesized by impregnating an anti-isomer of 5,8-dietyl-7-hydroxy-6-dodecanonoxime (DEHDO) as a hydroxyoxime-type extractant and a molecule modifier of 1-dodecanol into a SiO2-P support, where “P” indicates the polymerized styrene–divinylbenzene inside macroporous SiO2 particles. Adsorption and separation behaviors of Mo(VI) in HNO3 solutions onto the adsorbent were investigated by batch and column methods, respectively. The adsorbent can effectively adsorb Mo(VI) in both methods. In addition, Pd(II) and Zr(IV) contained in the simulated high-level liquid waste were successfully isolated by the adsorbent packed column, respectively.

Rice is the most commonly consumed grain in the world. Black rice has been suggested to contain various bioactive compounds including anthocyanin antioxidants. There is currently little information about the nutritional benefits of black rice on brain pathology. Here, we investigated the effects of black rice (Oryza sativa L., Poaceae) extract (BRE) on the hippocampal neuronal damage induced by ischemic insult. BRE (300 mg/kg) was orally administered to adult male C57BL/6 mice once a day for 21 days. Bilateral common carotid artery occlusion (BCCAO) was performed for 23 min on the 8th day of BRE or vehicle administration. Histological analyses conducted on the 22nd day of BRE or vehicle administration revealed that administering BRE profoundly attenuated neuronal cell death, inhibited reactive astrogliosis, and prevented loss of glutathione peroxidase expression in the hippocampus when compared to vehicle treatment. In addition, BRE considerably ameliorated BCCAO-induced memory impairment on the Morris water maze test from the 15th day to the 22nd day of BRE or vehicle administration. These results indicate that chronic administration of BRE is potentially beneficial in cerebral ischemia., Graphical Abstract

Recently, various functional construction materials based on carbon nanotubes (CNTs) are being researched; however, there are very few examples of practical use due to cost and workability obstacles. In order to overcome these limitations, we studied the electrical characteristics of multi-phase cement composites containing multi-walled carbon nanotubes (MWCNTs) and economical pitch-based carbon fiber (CF). Test specimens with various formulations of the CF length, content, and water/cement (w/c) ratio are manufactured and their properties are evaluated. The pitch-based CFs used in the experiments were analyzed by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The resistance of the conductive cement composites was measured by a two-probe method, and the viscosity was evaluated using a rheometer immediately after the mixing process. In addition, the internal structure of the specimens was analyzed using a scanning electron microscope (SEM) and by micro-computed tomography (Micro-CT) analyses. It was observed that the incorporation of CFs into the CNT-embedded cement composite causes the CFs to serve as a bridge between CNT particles, thus maintaining the homogeneity of the conductive network in the composites. In addition, although an increase of the w/c ratio improved the viscosity of the composites by 90%, the electrical resistivity was retained due to the bridging effect of the CF.

Versatile biological activities of Hericium erinaceus (HE) have been reported in many brain diseases. However, roles of HE in major psychiatric disorders such as depression and anxiety remain to be investigated. Therefore, we evaluated whether HE could reduce anxiety and depressive behaviors in the adult mouse and its underlying mechanisms. Male C57BL/6 mice were administered HE (20 or 60 mg/kg, p.o.) or saline once a day for 4 weeks. Open field and tail suspension tests were performed 30 min after the last administration of HE, followed by forced swim test 2 days later. We found that chronic administration of HE showed anxiolytic and antidepressant-like effects. To elucidate possible mechanisms, proliferative activity of the hippocampal progenitor cells was assessed by immunohistochemistry of proliferating cell nuclear antigen (PCNA) and Ki67. Moreover, to evaluate neuronal survival in the dentate gyrus, 5-bromo-2'-deoxyuridine (BrdU) (120 mg/kg, i.p.) was given at the first day of HE administration, followed by isolation of the brains 4 weeks later. HE (60 mg/kg) increased the number of PCNA- and Ki67-positive cells in the subgranular zone of the hippocampus, indicating increased proliferation of hippocampal progenitors. In addition, BrdU- and BrdU/NeuN-positive cells in the dentate gyrus were significantly increased when treated with HE (60 mg/kg) compared with the saline-treated group, demonstrating enhanced neurogenesis by HE treatment. Taken together, the results indicate that chronic HE administration can exert anxiolytic and antidepressant-like effects, possibly by enhancing adult hippocampal neurogenesis.

The importance of the thermal conductivity of engineering plastics reinforced with nanofillers is increasing in various industries, and the need for a model with which to make reliable predictions continues. We propose a micromechanics-based multiscale model that considers multi-shaped nanofillers to predict the thermal conductivity of composites. The distribution of each phase is assumed to be probabilistically distributed, and the Kapitza resistance at the interface between the filler and matrix was calculated by means of a molecular dynamics simulation. A polybutylene terephthalate (PBT) composite system embedded with multi-walled carbon nanotubes (MWCNTs) was used in a specific simulation. Composites containing MWCNTs of different lengths were also fabricated to obtain appropriate experimental results for the verification of the proposed model. Fourier-transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and field-emission scanning microscopy (FE-SEM) were carried out to confirm that the selected materials could suitably be compared. Finally, the proposed model was applied to the finite element method to examine the heat flux of the composites according to the constitutive properties, and their results were compared to the experimental results.

Lin28 has been shown to promote proliferation of progenitors and survival of neurons during cortical neurogenesis. However, the role of Lin28 in the terminal maturation of neurons remains obscured. In this study, we investigated the developmental impact of Lin28 overexpression on neurite outgrowth. Lin28 expression was upregulated by in utero electroporation at E14.5. Two days later, electroporated cortices were dissociated for culturing primary cortical neurons. We found that Lin28 overexpression, which was confirmed immunocytochemically, led to neurite underdevelopment for all time points during culture. Specifically, Lin28-overexpressing cells displayed significantly fewer primary neurites and a decreased dendritic branching index, compared to GFP-expressing controls. Additionally, Lin28 overexpression in primary cortical neurons induced the expression of high mobility group AT-Hook 2 (HMGA2). Taken together, our study demonstrates that constitutive Lin28 expression disrupts cortical neurogenesis resulting in impaired neurite outgrowth with a concomitant induction of HMGA2.

To estimate the applicability of thiodiglycolamide-type extractant-impregnated adsorbents to separation of the platinum group metals (PGMs) from high-level liquid waste, radiation effects on the adsorption behavior of PGMs onto a macroporous silica-based (Crea-TOA)/SiO 2 -P absorbent and on the stability of the adsorbent were investigated by using γ-rays emitted from 60 Co, and the results were compared with those obtained using (MOTDGA-TOA)/SiO 2 -P. A difference in adsorption behaviors of PGMs onto the two adsorbents was not observed with or without irradiation up to 100 kGy of the absorbed dose. Decomposition of the impregnated extractants and degradation of the adsorption capability increased with increasing absorbed dose, but the distribution coefficient of Pd remained >10 2 up to approximately 250 kGy. The retention ratio of loaded PGMs gradually decreased with increasing absorbed dose. From these results, the adsorbents were considered to be useful for the adsorption of PGMs irrespective of whether the adsorption system was irradiated, except for when the adsorbent was irradiated by a very large dose.

To assess radionuclide migration, Ca/Si ratio of calcium silicate hydrate (CSH) gel formed as a secondary mineral is a key factor because CSH gels effectively adsorb radionuclides, in particular cationic nuclides. However, the Ca/Si ratio of the CSH gel is changed by the leaching of Ca ions and the formation conditions. In this study, the influence of carbonate ions on the sorption of Cs ions on the CSH gel was preliminarily examined. For the sorption experiments, the concentrations of carbonate ions (NaHCO3) were adjusted to 0 mM-1000 mM at the synthesis of the CSH gel or after a 7-day curing period. As a result, the sorption of Cs ions on the CSH gel became larger with the increase in the concentration of carbonate ions. Such sorption behavior was also observed when carbonate ions were added after curing the CSH gel. These results suggest that CSH gel formed as a secondary mineral might be able to contribute to the retardation of radionuclide migration by interacting with carbonate ions.

4’4’(5’)-di( tert -butylcyclohexano)-18-crown-6 (DtBuCH18C6) modified with 1-ethyl-3-methylimidazolium bis (trifluoro methylsulfonyl) imide ([C 2 mim][NTf 2 ]) was loaded onto porous silica/polymer composite support (SiO 2 -P) particles with a mean diameter of 50 μm and used to extract Sr(II) from HNO 3 solutions. The effect of HNO 3 concentration on the equilibrium kinetics and thermodynamic properties of Sr(II) uptake were investigated by batch methods. The adsorbent exhibited excellent adsorption selectively for Sr(II) over a wide range of HNO 3 concentrations. The adsorption of Sr(II) in the presence of 3 M HNO 3 on (DtBuCH18C6+[C 2 mim][NTf 2 ])/SiO 2 -P attained equilibrium within 1 h, and a relatively large distribution coefficient ( K d ) of ca. 30 cm 3 ·g −1 was obtained. Kinetic data were successfully modeled using pseudo-second-order kinetics. The adsorption of Sr(II) was a spontaneous and exothermic process. The uptake isotherm of Sr(II) for (DtBuCH18C6+[C 2 mim][NTf 2 ])/SiO 2 -P followed a Langmuir-type adsorption equation.

Numerous studies have been reported on thermal interface materials based on synergistic hybrid effects, however, most of them contain only fragmentary experimental results and the related model has been rarely proposed to explain the effects exactly. Herein, the thermal conductivities of the composites were systematically evaluated according to various filler contents and ratios. It was found that the fraction of the secondary filler inducing the maximum synergistic effect decreased as the total filler content increased. In addition, when the fraction was higher than the optimum fraction, the anti-synergistic effect occurred. At the optimum fraction, effective phonon transfer was induced due to the improved filler network formation of graphene nanoplatelet (GNP)-carbon nanotube (CNT), thereby achieving high thermal conductivity of 7.69 W/m·K at fGNP = 27.69 vol% and fCNT = 0.57 vol%. Moreover, the Kim-Jang-Lee (KJL) model for the synergistic effect was proposed by introducing filler-ratio variables into the critical percolation equation reported previously, and the KJL model for the anti-synergistic effect was proposed based on the rule of mixture of composites filled with the optimal connected filler network and filled with the excessive secondary filler.

The use of hybrid fillers consisting of phycochemically different nanoparticles has been widely investigated to realize synergistic improvement of thermal conduction behaviors. The enhancement of thermal conductivity of composites is often limited by the thermal contact resistance of the reinforcing particles. We prepare a series of hybrid nanofiller reinforced composites composed of two-dimensional boron nitrides and one-dimensional multiwalled carbon nanotubes to investigate the interfacial thermal resistances of the composites by a finite element method. The interfacial thermal resistances calculated by the finite element modeling are implemented into a Mori–Tanaka homogenization scheme to predict the thermal conductivities of the composites with perfect and imperfect interfaces. The prediction by the Mori–Tanaka method was in good agreement with the finite element simulation and the experimental results.

In this study, electrospun Nylon-6,6 nanofiber (Nylon-6,6 NFs) reinforced cyclic butylene terephthalate (CBT) composites were prepared by electrospinning process followed by hot press method and compared with the pristine Nylon-6,6 nanofiber in terms of tensile properties and light transparency. The formation of hydrogen bonds between CBT and nylon-6,6 molecules results enhancement of the mechanical property of the composite. Further, the high optical transmittance of the composite was achieved.

A series of polyketone (PK) nanocomposite films with varying content of noncovalently functionalized graphene nanoplatelet with 1-aminopyrene (GNP/APy) is prepared by solution blending with a solvent of hexafluoro-2-propanol. GNP/APy, prepared by a facile method, can effectively induce specific interaction such as hydrogen bonding between the amine functional group of GNP/APy and the carbonyl functional group of the PK matrix. With comparison of GNP and GNP/Py as reference materials, intensive investigation on filler-matrix interaction is achieved. In addition, the dispersion state of the functionalized GNP (f-GNPs; GNP/Py and GNP/APy) in the PK matrix is analyzed by three-dimensional nondestructive X-ray microcomputed tomography, and the increased dispersion state of those fillers results in significant improvement in the water vapor transmission rate (WVTR). The enhancement in WVTR of the PK/GNP/APy nanocomposite film at 1 wt % loading of filler leads to a barrier performance approximately 2 times larger compared to that of PK/GNP nanocomposite film and an approximately 92% reduction in WVTR compared to the case of pristine PK film. We expect that this facile method of graphene functionalization to enhance graphene dispersibility as well as interfacial interaction with the polymer matrix will be widely utilized to expand the potential of graphene materials to barrier film applications.

We proposed a solvent-free melting process for fabricating high-conductivity polymer composite films filled with highly dispersed GNP fillers. The excellent dispersion of GNP fillers in the composite films was observed using X-ray micro-computed tomography (micro-CT), a non-destructive three-dimensional (3D) analysis technique that helps to analyze the internal structures of composite films with precision. The excellent dispersion of GNP fillers also confirmed by the fact that experimentally determined electrical and thermal conductivity values of the composite films were well consistent with the theoretical calculations obtained with a Mori-Tanaka method. The composite films exhibited an electrical conductivity on the order of 101 S/m and the in-plane thermal conductivity of 7.1 W/m·K when they contained 20 wt% GNP fillers.

We found that the thermal conductivity of the polycarbonate (PC) composite filled with both 9.9 wt% expanded graphite (EG) and 0.1 wt% multi-walled carbon nanotube (MWCNT) fillers was synergistically improved by 49% compared to that of the PC composite filled with 10 wt% EG alone. In order to induce the optimal internal structure favorable for thermal conduction by enhancing the dispersion of the second MWCNT fillers, we applied a two-step melt-compounding to fabricate composites using a MWCNT masterbatch based on a polymerizable oligomer resin, cyclic butylene terephthalate (CBT), which is characterized by ultra-low viscosity and excellent impregnability during initial melting. Three-dimensional (3D) non-destructive characterization using X-ray micro computed tomography (micro-CT) was utilized to demonstrate the synergistic enhancement and to verify dispersion and 3D thermal network of the fillers in the composites accurately. The synergistic enhancement was significantly affected by the formation of the efficient thermally conductive pathways and dispersion of the second MWCNT fillers.

The nanoscopic characteristics of the multi-walled carbon nanotubes (MWCNTs) used in composites are crucial for attempting to understand and design nanocomposites of a novel class. We investigate the correlations between the nanofiller properties and effective electrical properties of MWCNT-embedded polycarbonate composites by theoretical and experimental approaches. A probabilistic computational model is proposed to predict the influence of MWCNT morphology on the electrical behaviors of MWCNTs-embedded polymer composites. A parameter optimization method in accordance with a genetic algorithm is then applied to the model, resulting that the ideal sets of model constant for the simulation are computationally estimated. For the experimental validation purpose, a comparison between the present theoretical and experimental results is made to assess the capability of the proposed methods. In overall, good agreement between the predictions and experimental results can be observed and the electrical performance of the composites can be improved as the MWCNT length increases.

Status epilepticus is the most common serious neurological condition triggered by abnormal electrical activity, leading to severe and widespread cell loss in the brain. Lithium has been one of the main drugs used for the treatment of bipolar disorder for decades, and its anticonvulsant and neuroprotective properties have been described in several neurological disease models. However, the therapeutic mechanisms underlying lithium's actions remain poorly understood. The muscarinic receptor agonist pilocarpine is used to induce status epilepticus, which is followed by hippocampal damage. The present study was designed to investigate the effects of lithium post-treatment on seizure susceptibility and hippocampal neuropathological changes following pilocarpine-induced status epilepticus. Status epilepticus was induced by administration of pilocarpine hydrochloride (320 mg/kg, i.p.) in C57BL/6 mice at 8 weeks of age. Lithium (80 mg/kg, i.p.) was administered 15 minutes after the pilocarpine injection. After the lithium injection, status epilepticus onset time and mortality were recorded. Lithium significantly delayed the onset time of status epilepticus and reduced mortality compared to the vehicle-treated group. Moreover, lithium effectively blocked pilocarpine-induced neuronal death in the hippocampus as estimated by cresyl violet and Fluoro-Jade B staining. However, lithium did not reduce glial activation following pilocarpine-induced status epilepticus. These results suggest that lithium has a neuroprotective effect and would be useful in the treatment of neurological disorders, in particular status epilepticus.

The recharge fractions of injection water in combined abstraction-injection wells (AIW) were determined using continuous radon monitoring and radon mass balance model. The recharge system consists of three combined abstraction-injection wells, an observation well, a collection tank, an injection tank, and tubing for heating and transferring used groundwater. Groundwater was abstracted from an AIW and sprayed on the water-curtain heating facility and then the used groundwater was injected into the same AIW well by the recharge system. Radon concentrations of fresh groundwater in the AIWs and of used groundwater in the injection tank were measured continuously using a continuous radon monitoring system. Radon concentrations of fresh groundwater in the AIWs and used groundwater in the injection tank were in the ranges of 10,830–13,530 Bq/m3 and 1500–5600 Bq/m3, respectively. A simple radon mass balance model was developed to estimate the recharge fraction of used groundwater in the AIWs. The recharge fraction in the 3 AIWs was in the range of 0.595–0.798. The time series recharge fraction could be obtained using the continuous radon monitoring system with a simple radon mass balance model. The results revealed that the radon mass balance model using continuous radon monitoring was effective for determining the time series recharge fractions in AIWs as well as for characterizing the recharge system.

Regulator of calcineurin 1 (RCAN1) can be induced by an intracellular calcium increase and oxidative stress, which are characteristic features of temporal lobe epilepsy. Thus, we investigated the spatiotemporal expression and cellular localization of RCAN1 protein and mRNA in the mouse hippocampus after pilocarpine-induced status epilepticus (SE). Male C57BL/6 mice were given pilocarpine hydrochloride (280 mg/kg, i.p.) and allowed to develop 2 h of SE. Then the animals were given diazepam (10 mg/kg, i.p.) to stop the seizures and sacrificed at 1, 3, 7, 14, or 28 day after SE. Cresyl violet staining showed that pilocarpine-induced SE resulted in cell death in the CA1 and CA3 subfields of the hippocampus from 3 day after SE. RCAN1 immunoreactivity showed that RCAN1 was mainly expressed in neurons in the shammanipulated hippocampi. At 1 day after SE, RCAN1 expression became detected in hippocampal neuropils. However, RCAN1 signals were markedly enhanced in cells with stellate morphology at 3 and 7 day after SE, which were confirmed to be reactive astrocytes, but not microglia by double immunofluorescence. In addition, real-time reverse transcriptase–polymerase chain reaction showed a significant upregulation of RCAN1 isoform 4 (RCAN1-4) mRNA in the SE-induced hippocampi. Finally, in situ hybridization with immunohistochemistry revealed astrocytic expression of RCAN1-4 after SE. These results demonstrate astrocytic upregulation of RCAN1 and RCAN1-4 in the mouse hippocampus in the acute and subacute phases of epileptogenesis, providing foundational information for the potential role of RCAN1 in reactive astrocytes during epileptogenesis.

The gene associated with retinoid-interferon-induced mortality-19 (GRIM-19) plays several significant roles in cellular processes, including ATP synthesis, reactive oxygen species formation, and the regulation of glycolytic enzyme activity, which are closely related to the pathophysiological mechanisms of epilepsy. Therefore, we investigated the expression pattern of GRIM-19 in the CA1 area of the hippocampus in 8-week-old male C57BL/6 mice following pilocarpine-induced status epilepticus (SE). Neuronal death in the hippocampal CA1 area was prominently observed at 4 and 7 days after SE, and astrocytes and microglia became progressively activated beginning at 1 day after SE. GRIM-19 immunoreactivity was decreased in the damaged pyramidal cell layer but markedly increased in the stratum radiatum and stratum lacunosum-moleculare of the hippocampus at 4 and 7 days after SE. In addition, the cell types of GRIM-19-expressing cells in the epileptic hippocampus were identified. GRIM-19 was mainly co-localized in neurons but only slightly expressed in glia in the normal hippocampus. Most of the GRIM-19-positive cells induced by SE in the stratum radiatum and stratum lacunosum-moleculare were glial fibrillary acidic protein-expressing reactive astrocytes. Moreover, we observed that both GRIM-19 and pyruvate kinase isozyme M2, a glycolytic enzyme, were highly expressed in reactive astrocytes after SE. These results indicate that expression of GRIM-19 in the hippocampus is mainly observed in neurons under normal conditions but is altered in the SE mouse model as evidenced by its increased expression in reactive astrocytes. The possible role of GRIM-19 in the glycolytic activity of reactive astrocytes is also discussed.

Vascular endothelial growth factor (VEGF)-C and its receptor, vascular endothelial growth factor receptor (VEGFR)-3, are responsible for lymphangiogenesis in both embryos and adults. In epilepsy, the expression of VEGF-C and VEGFR-3 was significantly upregulated in the human brains affected with temporal lobe epilepsy. Moreover, pharmacologic inhibition of VEGF receptors after acute seizures could suppress the generation of spontaneous recurrent seizures, suggesting a critical role of VEGF-related signaling in epilepsy. Therefore, in the present study, the spatiotemporal expression of VEGF-C and VEGFR-3 against pilocarpine-induced status epilepticus (SE) was investigated in C57BL/6N mice using immunohistochemistry. At 1 day after SE, hippocampal astrocytes and microglia were activated. Pyramidal neuronal death was observed at 4 days after SE. In the subpyramidal zone, VEGF-C expression gradually increased and peaked at 7 days after SE, while VEGFR-3 was significantly upregulated at 4 days after SE and began to decrease at 7 days after SE. Most VEGF-C/VEGFR-3-expressing cells were pyramidal neurons, but VEGF-C was also observed in some astrocytes in sham-manipulated animals. However, at 4 days and 7 days after SE, both VEGFR-3 and VEGF-C immunoreactivities were observed mainly in astrocytes and in some microglia of the stratum radiatum and lacunosum-moleculare of the hippocampus, respectively. These data indicate that VEGF-C and VEGFR-3 can be upregulated in hippocampal astrocytes and microglia after pilocarpine-induced SE, providing basic information about VEGF-C and VEGFR-3 expression patterns following acute seizures.

Hericium erinaceus (HE), a culinary-medicinal mushroom, has shown therapeutic potential in many brain diseases. However, the role of HE in status epilepticus (SE)-mediated neuronal death and its underlying mechanisms remain unclear. We investigated the neuroprotective effects of HE using a pilocarpine-induced SE model. Male C57BL/6 mice received crude extracts of HE (60 mg/kg, 120 mg/kg, or 300 mg/kg, p.o.) for 21 d from 14 d before SE to 6 d after SE. At 7 d after SE, cresyl violet and immunohistochemistry of neuronal nuclei revealed improved hippocampal neuronal survival in animals treated with 60 mg/kg and 120 mg/kg of HE, whereas those treated with 300 mg/kg of HE showed similar neuronal death to that of vehicle-treated controls. While seizure-induced reactive gliosis, assessed by immunohistochemistry, was not altered by HE, the number of hippocampal cyclooxygenase 2 (COX2)-expressing cells was significantly reduced by 60 and 120 mg/kg of HE. Triple immunohistochemistry demonstrated no overlap of COX2 labeling with Ox42, in addition to a decrease in COX2/GFAP-co-immunoreactivity in the group treated with 60 mg/kg HE, suggesting that the reduction of COX2 by HE promotes neuroprotection after SE. Our findings highlight the potential application of HE for preventing neuronal death after seizures.

Gene associated with retinoid-interferon-induced mortality-19 (GRIM-19) is a subunit of the mitochondrial respiratory chain complex I that has a significant effect on ATP production. The brain is particularly susceptible to ATP deficiency due to its limited energy storage capability and its high rate of oxygen consumption. Thus, GRIM-19 might be involved in regulating ATP level in the brain or cell death caused by several neurological disorders. To understand the physiological and pathophysiological roles of GRIM-19 in the brain, a thorough investigation of the neuroanatomic distribution of GRIM-19 in the normal brain is necessary. Therefore, the present study examined the distribution patterns of GRIM-19 in the adult C57BL/6 mouse brain using immunohistochemistry and identified cell types expressing GRIM-19 using double immunofluorescence staining. We found that GRIM-19 was ubiquitously but not homogenously expressed throughout the brain. GRIM-19 immunoreactivity was predominantly observed in neurons, but not in astrocytes, microglia, or oligodendrocytes under normal physiological conditions. Following transient global cerebral ischemia, GRIM-19-positive immunoreactivity was, however, observed in neurons as well as glial cells including astrocytes in the hippocampus. Furthermore, GRIM-19 was weakly expressed in the hippocampal subgranular zone, in which neural stem and progenitor cells are abundant, but highly expressed in the immature and mature neuronal cells in the granular cell layer of the normal brain, suggesting an inverse correlation between expression of GRIM-19 and stemness activity. Collectively, our study demonstrating widespread and differential distribution of GRIM-19 in the adult mouse brain contributes to investigating the functional and pathophysiological roles of this protein.

We report the rare-earth-free Sr2YSbO6 (SYS):Mn4+ phosphors with excellent photoluminescence performance for indoor illuminations. The phase structure, elemental composition, luminescence behavior, thermal stability, lifetime, color purity, and quantum yield (QY) were analyzed in detail. The resultant sample showed a broadband excitation wavelength in the range of 250–450 nm, and the optimal doping concentration was 0.5 mol%. Under the suitable excitation wavelength of 307 nm, the SYS:0.005Mn4+ phosphor emitted a deep-red emission with the Commission Internationale de I'Eclairage chromaticity coordinate of (0.708, 0.290) and a high color purity of 93.34%. The emission intensity was found to be about 59.45% at 423 K while the activation energy was 0.28 eV. Moreover, the lifetime and QY of the optimal sample were measured to be 641.58 µs and 38.37%, respectively. Eventually, the white lighting-emitting didoes (LEDs) exhibited a strong white light with good color-rendering index (CRI) and correlated color temperature (CCT) values. Besides that, the novel LED structure based on the SYS:0.005Mn4+-polydimethylsiloxane film could also emit a warm white region while the CRI and CCT values were measured to be about 81.39 and 3091 K.

Self-reinforced composites (SRCs) are easy to recycle because the matrix and reinforcement are composed of the same material. However, the narrow processing window makes it difficult to optimize the relationship between the internal structure and the mechanical properties. In this study, we adopted a strategy to control the melting temperature and flowability of the matrix to expand the processing window of a polypropylene (PP)-based SRC. To experiment with this strategy, 1500% drawn PP fiber was used as the reinforcement, while a PP/low-density polyethylene (LDPE) blend, PP/ethylene copolymer, or PP/ethylene/butene terpolymer were adopted as the matrix. The tensile strength of the PP-based SRC prepared by applying the copolymer matrix under optimized processing conditions was improved by 22.3%, as compared to that of the SRC prepared using the raw PP matrix. As a result, the design rule used to obtain optimum processing conditions for SRC production with outstanding mechanical properties was proposed.

Polypropylene-grafted-maleic anhydride (PP-g-MAH) is known as an excellent interface modifier that can improve the interface between carbon fiber (CF) and PP. In this study, the effect of PP-g-MAH content on the physical properties of PP composites containing long-fiber CFs was investigated. It was confirmed that PP-g-MAH acted as an interface modifier between the interface between CF and PP, and when an appropriate amount of 10 wt% was incorporated, the tensile strength, tensile modulus, Izod impact strength, and heat deflection temperature were improved by 110%, 50%, 86.7% and 12.7%, respectively. On the other hand, the blending effect of PP-g-MAH, which is a low molecular weight, was greater than the compatibilizing effect when the PP-g-MAH content was mixed above the appropriate content, thereby reducing the physical properties. Therefore, the content of PP-g-MAH as the interface modifier must be designed to be the optimum content considering the CF content to be mixed in order to optimize the physical properties of the composite material.

The size of expanded graphite (EG) was controlled using a high-speed crusher because a hybrid of differently sized fillers can induce a synergistic enhancement of the thermal conductivity in polymer composites. We found that the thermal conductivity of a polymer composite filled with both 10 wt% EG and 10 wt% high-speed crusher treated EG (wEG) was synergistically improved by 12.0 and 20.7% compared to that of polymer composites filled with 20 wt% EG and 20 wt% wEG alone, respectively. A three-dimensional (3D) non-destructive analysis using X-ray micro-computed tomography (micro-CT) was applied to explain the synergistic enhancement and to identify the dispersion and 3D network of EG fillers in the composites accurately. According to the non-destructive analysis results, the synergistic enhancement was caused by the formation of efficient thermally conductive pathways due to the hybrid of the differently sized EG and wEG fillers.

We found that the thermal conductivity of polymer composites was synergistically improved by the simultaneous incorporation of graphene nanoplatelet (GNP) and multi-walled carbon nanotube (MWCNT) fillers into the polycarbonate matrix. The bulk thermal conductivity of composites with 20 wt% GNP filler was found to reach a maximum value of 1.13 W/m K and this thermal conductivity was synergistically enhanced to reach a maximum value of 1.39 W/m K as the relative proportion of MWCNT content was increased but the relative proportion of GNP content was decreased. The synergistic effect was theoretically estimated based on a modified micromechanics model where the different shapes of the nanofillers in the composite system could be taken into account. The waviness of the incorporated GNP and MWCNT fillers was found to be one of the most important physical factors determining the thermal conductivity of the composites and must be taken into consideration in theoretical calculations.

Double-sided strip detectors were fabricated from thallium bromide (TlBr) crystals grown by the traveling-molten zone method using zone-purified materials. The detectors had three 3.4-mm-long strips with 1-mm widths and a surrounding electrode placed orthogonally on opposite surfaces of the crystals at approximately 6.5×6.5 mm2 in area and 5 mm in thickness. Excellent charge transport properties for both electrons and holes were observed from the TlBr crystals. The mobility-lifetime products for electrons and holes in the detector were measured to be ~3×10−3 cm2/V and ~1×10−3 cm2/V, respectively. The 137Cs spectra corresponding to the gamma-ray interaction position were obtained from the detector. An energy resolution of 3.4% of full width at half maximum for 662-keV gamma rays was obtained from one “pixel” (an intersection of the strips) of the detector at room temperature.

In this study, simultaneous separation and recovery of Cs(I) and Sr(II) from nitric acid solution was investigated using a silica-based hybrid adsorbent. The adsorbent was prepared by successive impregnation and fixing of two supramolecular recognition agents namely, 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-Calix[4]-arene(Calix[4]arene-R14) and 4',4' (5")-di(tert-butylcyclohexano)-18-crown-6, onto a silica-based polymer support(SiO2-P). Uptake properties, characterization, equilibrium kinetics, and dynamic adsorption properties of Cs(I) and Sr(II) were then assessed. Distribution coefficients (Kd) higher than 102 cm3/g for Cs(I) and Sr(II) were obtained using 3 M HNO3 at 298 K, and the Kd values decreased with increasing temperature. Adsorption kinetics and equilibrium studies fitted well with pseudo-second-order model and Redlich–Peterson isotherm model, respectively. The constant total organic carbon values in the aqueous phase were obtained after adding 10−3 ∼ 4 M HNO3. Results of the dyn...

We used X-ray computed tomography (CT) using characteristic X-rays produced in micro-particle-induced X-ray emission (PIXE) to investigate the internal structure of silt particles and develop new methods to decontaminate soil containing radioactive cesium. We obtained 3D attenuation coefficient images of silt particles with a diameter of approximately 100 μm for V K and Cr K X-rays. Owing to the absorption edges of the Cs L-shell, the differences between the V K and Cr K X-ray images revealed the spatial distribution of Cs atoms in the silt particles. Cs atoms were distributed over the surfaces of the silt particles to a thickness of approximately 10 μm. This information is useful for the decontamination of silt contaminated by radiation from the Fukushima Daiichi nuclear disaster.

Ampicillin, a β-lactam antibiotic, dose-dependently protects neurons against ischemic brain injury. The present study was performed to investigate the neuroprotective mechanism of ampicillin in a mouse model of transient global forebrain ischemia. Male C57BL/6 mice were anesthetized with halothane and subjected to bilateral common carotid artery occlusion for 40 min. Before transient forebrain ischemia, ampicillin (200 mg/kg, intraperitoneally [i.p.]) or penicillin G (6,000 U/kg or 20,000 U/kg, i.p.) was administered daily for 5 days. The pretreatment with ampicillin but not with penicillin G signifi cantly attenuated neuronal damage in the hippocampal CA1 subfield. Mechanistically, the increased activity of matrix metalloproteinases (MMPs) following forebrain ischemia was also attenuated by ampicillin treatment. In addition, the ampicillin treatment reversed increased immunoreactivities to glial fibrillary acidic protein and isolectin B4, markers of astrocytes and microglia, respectively. Furthermore, the ampicillin treatment significantly increased the level of glutamate transporter-1, and dihydrokainic acid (DHK, 10 mg/kg, i.p.), an inhibitor of glutamate transporter-1 (GLT-1), reversed the neuroprotective effect of ampicillin. Taken together, these data indicate that ampicillin provides neuroprotection against ischemia-reperfusion brain injury, possibly through inducing the GLT-1 protein and inhibiting the activity of MMP in the mouse hippocampus.

The oxidation behavior of chromium and the corrosion behavior of austenitic stainless steel in boiling nitric acid solution containing highly concentrated nitrates were investigated using UV-visible spectroscopic measurements, Raman spectral measurements, immersion tests, and potentiodynamic polarization measurements. The oxidation rate measurement of chromium from Cr(III) to Cr(VI) was performed by 1 M boiling nitric acid solution containing each highly concentrated nitrates: Al(NO3)3, Nd(NO3)3, Ca(NO3)2, Mg(NO3)2, and NaNO3 as a simulant of uranium nitrate in uranium concentrator in reprocessing plants. As a result, the rate of chromium oxidation was different depending on the added nitrates even at the same nitric acid concentration. In addition, the oxidation rate of chromium was increased with increasing the calculated partial pressure of nitric acid in consideration of the hydration of cation of nitrates. Furthermore, the corrosion rate of type 310 stainless steel was accelerated by the solu...

Despite the benefits of recycling, impact resistance, and lightweightness, polypropylene (PP) self-reinforced composites (SRCs) still suffer from a lack of research, especially in continuous manufacturing processes. Herein we report a comprehensive study, from the four-step high-ratio drawing of PP-tapes to the continuous manufacturing of SRCs. The mechanical properties of the PP-tape depend strongly on the final draw ratio with the intermediate drawing history having a negligible effect. Mechanical improvements accompany increases in melting temperature and crystallinity, and a decrease in density. PP-SRC was manufactured by continuous double-belt pressing, with optimum performance attained when processed with a 87-148-80 (°C) temperature profile. Structural integrity was not attained at lower temperatures due to poor impregnation, whereas higher temperatures degraded the mechanical properties of the PP-SRC by relaxing the highly drawn PP-tapes. Finally, an analytical approach based on micro-computed tomography, PP-tape relaxation, and rule-of-mixture calculations led to accurate predictions of experimental moduli.

Achieving high filler dispersion in a polymer composite is very important for effectively and efficiently imparting several advantages of functional fillers to the composite. To this end, we have suggested a synthesis of polyamide 6 via in situ ring-opening polymerization of e-caprolactam and edge-selectively functionalized graphene nanoplatelets without defects on its basal plane synthesized by a ball-mill process with dry ice. As a consequence, the final graphene nanocomposite possesses highly dispersed filler and has enhanced electrical conductivity due to its undistorted sp2 hybridization after functionalization. This approach is a promising way of incorporating filler into polymer composites, effectively implementing highly electrical conducting graphene without its aggregation and damage to its inherent properties after functionalization.

Regulator of calcineurin 1 (RCAN1) can be induced by an intracellular calcium increase and oxidative stress, which are characteristic features of temporal lobe epilepsy. Thus, we investigated the spatiotemporal expression and cellular localization of RCAN1 protein and mRNA in the mouse hippocampus after pilocarpine-induced status epilepticus (SE). Male C57BL/6 mice were given pilocarpine hydrochloride (280 mg/kg, i.p.) and allowed to develop 2 h of SE. Then the animals were given diazepam (10 mg/kg, i.p.) to stop the seizures and sacrificed at 1, 3, 7, 14, or 28 day after SE. Cresyl violet staining showed that pilocarpine-induced SE resulted in cell death in the CA1 and CA3 subfields of the hippocampus from 3 day after SE. RCAN1 immunoreactivity showed that RCAN1 was mainly expressed in neurons in the shammanipulated hippocampi. At 1 day after SE, RCAN1 expression became detected in hippocampal neuropils. However, RCAN1 signals were markedly enhanced in cells with stellate morphology at 3 and 7 day after SE, which were confirmed to be reactive astrocytes, but not microglia by double immunofluorescence. In addition, real-time reverse transcriptase-polymerase chain reaction showed a significant upregulation of RCAN1 isoform 4 (RCAN1-4) mRNA in the SE-induced hippocampi. Finally, in situ hybridization with immunohistochemistry revealed astrocytic expression of RCAN1-4 after SE. These results demonstrate astrocytic upregulation of RCAN1 and RCAN1-4 in the mouse hippocampus in the acute and subacute phases of epileptogenesis, providing foundational information for the potential role of RCAN1 in reactive astrocytes during epileptogenesis.

With the recent demand for miniaturization and integration of electronic devices, there has been a growing interest in device malfunction due to high temperature. In this study, a experimental and theoretical study on the composites with improved thermal conductivity by dispersing multi-walled carbon nanotubes (MWCNTs) in the thermoplastic resin was carried out. A micromechanical model was derived based on the ensemble volume-averaging method and the modified Eshelby’s tensor reflecting the interface properties. The effects of the waviness, interface, and orientation of fillers on the thermal conductivity of composites were numerically analyzed. A computational intelligence-based particle swarm optimization (PSO) algorithm was adopted to the proposed model for optimizing the model constants. The thermal conductivity of the polymerized cyclic butylene terephthalate (pCBT)/MWCNT composites was experimentally measured according to the content of MWCNT. Finally, the experimentally measured data were utilized in the PSO to improve the predictive capability of the proposed model.

In order to develop a nanocomposite film based on multi-walled carbon nanotubes (MWCNTs) as an electromagnetic wave shielding material, we propose a solvent-free melting process for fabricating highly dispersed MWCNT-filled polymer composite films with high electrical conductivity and electromagnetic interference (EMI)-shielding properties. By observing aggregates (particles larger than 0.7 μm) using X-ray micro-computed tomography (micro-CT), the uniform dispersion of the MWCNT fillers in the composite films was confirmed. Furthermore, the electrical conductivity and EMI shielding effectiveness (SE) values calculated using percolation and Simon's equations, respectively, were confirmed to agree with experimental data, indicating excellent MWCNT dispersion. The fabricated composites exhibited excellent electrical conductivity, EMI SE, and EMI specific SE (SSE) values of 4.33 S/cm, 30 dB, and of 24.8 dBcm3g−1, respectively, and the EMI SSE value was as good as metal levels. The proposed solvent-free process can be contributed to the commercialization of EMI SE composite films based on MWCNTs.

It is very important to predict any defects occurring by undesired fiber deformations to improve production yields of resin transfer molding, which has been widely used for mass production of carbon fiber reinforced composite parts. In this study, a simple and efficient analytic scheme was proposed to predict deformations of a multi-layered fiber preform by comparing the forces applied to the preform in a mold of resin transfer molding. Friction coefficient of dry and wet states, permeability, and compressive behavior of unidirectional (UD) and plain woven (PW) carbon fabrics were measured, which were used to predict deformations of the multi-layered fiber preforms with changing their constitution ratios. The model predicted the occurrence, type, and position of fiber deformation, which agreed with the experimental results of the multi-layered preforms.