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A novel ionic liquid (IL) functionalized with thiodiglycol amic acid containing a soft S donor was synthesized for the effective and efficient extraction of platinum group metals (Ru, Rh, and Pd) from aqueous nitric acid solutions, such as high-level radioactive liquid waste (HLLW). The IL enabled rapid extraction of Pd(II) with an extraction ratio of approximately 100%. The extractions of Ru(III) and Rh(III) by the IL were slower than that of Pd(II), but the rates were accelerated by temperature elevation. The extractions of Ru(III) and Rh(III) at 50 °C reached equilibrium within 4 and 8 h, respectively, with the extraction ratios of over 90% without assisting agents or other methods for the extraction system. Furthermore, the IL could extract more than 90% of Ru(III), Rh(III), and Pd(II) from the simulated HLLW within 2 h at 50 °C.

Aiming at selective adsorption and separation of Y(III) from the Y(III)-Sr(II) group in acid solution, a silica-based TODGA impregnated adsorbent [(TODGA+1-dodecanol)/SiO2-P-F600] has been prepared. Batch adsorption experiments were conducted under the effect of contact time, acid concentration, solution temperature, and adsorption capacity etc. Chromatography recovery of more than 90% Y(III) was successfully achieved under elution with 0.01 M DTPA solution in nitric acid adsorption system, and 0.1 M HCl solution in hydrochloride adsorption system, respectively.

A hydrophobic ionic liquid including an amino moiety ([DiOcAPmim][NTf2]) was synthesized. Its extraction behaviors towards Pd(II), Ru(III), Rh(III) were investigated in nitric acid aqueous solution as a function of contact time, effect of concentration of nitric acid, effect of temperature, and effect of co-existing metal ions. The extraction kinetics of Pd(II) was fairly fast and extraction equilibrium can be attained within only 5 min under the [HNO3] = 2.05 M. When [HNO3]< 1 M, the extraction percentage of Pd(II), Ru(III), Rh(III) were all above 80%. When [HNO3] reached 2 M, all of the extraction percentage decreased and in an order of Pd(II)>Ru(III)>Rh(III). When [HNO3]> 2 M, the extraction performance gradually recovered. The effect of temperature can slightly affect the extraction performance of Pd(II). Furthermore, in simulated high-level liquid waste, [DiOcAPmim][NTf2] showed a better preference towards Pd(II) under the interference of various other co-existing metal ions.

To efficiently separate Pd(II) from high-level liquid waste (HLLW), a (TEHTDGA + dodecanol)/SiO2-P silica-based adsorbent (TEHTDGA resin) was synthesized by impregnating SiO2-P particles with N,N,N���,N���-tetra-2-ethylhexyl-thiodiglycolamide (TEHTDGA) and dodecanol. Our experimental results indicate that TEHTDGA resin exhibits high distribution coefficients for Pd(II) at HNO3 concentrations from 0.1 M to 5.0 M. The adsorption behavior of Pd(II) was found to quickly reach an equilibrium state, with a nearly 100% uptake ratio. Based on adsorption isotherm analyses, the experimental results for Pd(II) fit well with the Langmuir isotherm model. TEHTDGA resin was also confirmed to exhibit high adsorption capacity for Pd(II). The adsorption behavior of Pd(II) was hardly affected by temperature. In an evaluation of the amount of leaked sulfur, TEHTDGA resin demonstrated good chemical stability. The results of a chromatography separation experiment indicate that almost all the Pd(II) could be successfully separated and recovered from simulated HLLW using 0.1 M thiourea in 0.01 M HNO3 solution as an eluent.

The adsorption behaviors of a silica-based hybrid donor adsorbent (TAMIA-EH+1-dodecanol)/SiO2-P towards Pd(II) were investigated under the effect of the contact time, temperature etc. in simulated high-level liquid waste. The adsorption rates of Pd(II) and Re(VII) were fairly fast and could reach the equilibrium state in only 1 h compared with other co-existing metal ions. The adsorption kinetics of Pd(II) was found to fit well with the pseudo-first order model. Even though with increasing the concentration of HNO3 above 1 M, the adsorption performance of (TAMIA-EH+1-dodecanol)/SiO2-P decreased gradually; it still exhibited a better selectivity towards Pd(II) when [HNO3] > 0.5 M. The adsorption isotherms of Pd(II) and Re(VII) were well-described by the Langmuir isotherm model, while the Freundlich isotherm model was considered to be more suitable for the adsorption of Ru(III), Zr(IV) and Mo(VI). A high temperature of an aqueous solution was not good for the effective recovery of Pd(II). The calculated thermodynamic parameters revealed that the adsorption of Pd(II) was exothermic in nature.

There is a growing demand for the development of a melt process-based nanocomposite manufacturing process capable of minimizing the incorporation of expensive carbon nanotubes (CNTs) by inducing a uniform dispersion of multi-walled CNTs (MWNTs). In this study, we proposed a nanocomposite manufacturing process that includes both physical particle mixing using high-speed rotation and anionic polymerization of e-caprolactam (CL) to induce a uniform dispersion of MWNTs. MWNTs were uniformly dispersed by powder mixing and then wrapped with polyamide 6 polymers by in-situ polymerization of CL. The synergistic effect of the two sub-processes resulted in an enhanced dispersion of MWNTs and prevented aggregation of the MWNTs. The composites fabricated by the proposed process exhibited electrical conductivities of 4.49 × 10−5 S/m and 1.45 × 10 S/m at 1 wt% and 3 wt% MWNTs, respectively, indicating that by applying the proposed process it is possible to incorporate a smaller amount of MWNT to achieve electrical conductivities applicable for electrostatic discharge (ESD) (>1 X 10−5 S/m) and electromagnetic interference shielding effectiveness (EMI SE) (>10 S/m) applications. An ESD chip tray and EMI SE mobile phone case were fabricated using the prepared composite, and it was verified that the ESD and EMI SE performances can be realized.

Silica aerogels have attracted great interest for several decades because of their super thermal insulation property, but their fragility has limited their application in every-day products. Here we describe a method to fabricate flexible and thermally-insulated composites by using a flexible poly(dimethylsiloxane) (PDMS) matrix and by preventing matrix impregnation of the silica aerogel pores. The silica aerogel was first mixed with ethanol to prevent impregnation of the silica aerogel pores with PDMS molecules. After composite fabrication, the ethanol was removed. The optimum PDMS composite had super thermal insulation (0.018 W/m·K) and was flame-retardant, in addition to being flexible. This method described here will facilitate the application of silica aerogel-incorporated composites as thermal insulation materials for products that require flexibility and flame-retardant properties.

Techniques for optimizing the dispersion of carbon nanotubes in composites by applying small amounts of additives in a simple manner are recognized as one of the most important core technologies in nanocomposite engineering. In this study, we reported the feasibility of phenyl glycidyl ether (PGE) as an effective noncovalent functionalization agent and suggested a facile and low-temperature process that applied high-speed rotation based on a planetary centrifugal mixer to improve the dispersion of multiwalled carbon nanotube (MWCNT) in the polyamide 6 (PA6) composite. PGE molecules were introduced on MWCNTs based on the π-π* interaction, resulting in enhanced MWCNT dispersion by preventing of the aggregation between the MWCNTs due to the van der Waals force. The tensile strength of the PA6 composite fiber filled with 1 wt% MWCNTs was improved up to 31.8% by the PGE treatment, indicating that PGE molecules were an effective noncovalent functionalization agent.

We herein propose a facile approach to fabricate foldable and coatable silica aerogel polyurethane composites (APCs). For the flexibility control, the soft segment of polyurethane (PU) is manipulated. The change in soft segment length induces a difference in overall glass transition temperature of PU. When the silica aerogel content is increased, the PU with a shorter soft segment length shows brittle fracture behavior, while the PU with a longer soft segment length shows no breakage after bending. The thermal insulation properties of APCs were enhanced by 72% reduction in thermal conductivity upon 30 wt% aerogel loading and theoretically verified by a micromechanics-based thermal conductivity model considering the effects of interface and agglomeration. In addition, for the combustion behavior measurements, heat release rate and heat release capacity are substantially reduced for the APCs compared to neat PUs. Those enhanced thermal insulation properties may have a commercial impact on thermal insulation applications.

An acid-stable 2D covalent organic framework (COF TpPa-1) was synthesized by a reversible Schiff-base reaction and the following irreversible enol-keto tautomerism. The adsorption behaviors of COF TpPa-1 towards Pd(II) in simulated high-level liquid waste (HLLW) were investigated under the effect of contact time, the concentration of nitric acid etc. The obtained experimental results supported that the utilization of this type of acid-stable COF in HLLW to recover metal ion was feasible.

To induce uniform dispersion and excellent interfacial properties, we adopted a strategy of combining both polyamide 6 (PA6) grafting for multi-walled carbon nanotubes (MWCNTs) and reactive extrusion of PA6 matrix, based on anionic ring-opening polymerization of &epsilon, caprolactam (CL). Compared to &ndash, COOH and &ndash, NCO treatments of MWCNTs, enhanced MWCNT dispersion and tensile properties of the composites were achieved using the applied strategy, and the tensile strength and modulus of the PA6-grafted MWCNT-filled PA6 composites were 5.3% and 20.5% higher than those of the purified MWCNT-filled PA6 composites, respectively. In addition, they were almost similar to the theoretical ones calculated by the modified Mori&ndash, Tanaka method (MTM) assuming a perfect interface, indicating that the tensile properties of MWCNT-filled PA6 composites can be optimized by PA6 grafting and reactive extrusion based on the anionic ring-opening polymerization of CL due to uniform MWCNT dispersion and excellent interfacial property.

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.

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.

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

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.

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.

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.