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Eriobotrya japonica leaf is included in the Chinese Pharmacopoeia, and is widely used as a medicinal material in traditional medicine. The present study investigated the potential genotoxic effects of E. japonica leaf extract (EJE) using three standard battery systems. Genotoxicity tests were conducted following the test guidelines of the Organisation for Economic Cooperation and Development (OECD) and Ministry of Food and Drug Safety (MFDS), with application of Good Laboratory Practice. The bacterial reverse mutation test was conducted using the pre-incubation method in the presence or absence of the metabolic activation system (S9 mixture). The in vitro chromosome aberration test was performed using cultured Chinese hamster lung cell line in the presence or absence of the S9 mixture. The in vivo micronucleus test was performed using ICR mice. The bacterial reverse mutation test with Salmonella typhimurium strains TA98, TA100, TA1535, and TA1537 and Escherichia coli strain WP2uvrA showed that EJE did not induce gene mutations at any dose level in all the strains tested. EJE also did not show any chromosomal aberrations in the in vitro chromosomal aberration test and in the in vivo micronucleus test. These results showed that EJE did not induce mutagenicity or clastogenicity in either in vitro or in vivo systems.

Due to success of desired doping, ion implantation has been widely used for semiconductor processing. In this work, we used nitrogen ion implantation to enhance magnetism in CeFe12 epitaxial thin films. To optimize nitrogen contents in CeFe12 and minimize the damage caused by the high-energy ion beam, we varied the thickness of the capping Mo layer. The saturation magnetization increased nearly 25% by nitrogen ion implantation into CeFe12 thin film. This phenomenon is explained by density functional theory calculations and confirmed by the magnetic resonance technique. The ion implantation and design strategy can be used for light-ion implantation into lattices to modulate magnetic, optical, and electrical properties.

The cycling and storage performances of LiCoO 2 (LCO)-LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM)/pitch-coated silicon alloy-graphite (Si-C) full cells with ethylene carbonate (EC)–based and fluoroethylene carbonate (FEC)–based electrolytes are investigated at elevated temperatures. Excess FEC (used as a co-solvent in LiPF 6 -based electrolytes), which is not completely consumed during the formation of the solid electrolyte interphase (SEI) layer on the electrodes, is prone to defluorination in the presence of Lewis acids such as PF 5 ; this reaction can generate unwanted HF and various acids (H 3 OPF 6 , HPO 2 F 2 , H 2 PO 3 F, H 3 PO 4 ) at elevated temperatures. Our investigation reveals that the HF and acid compounds that are formed by FEC decomposition causes significant dissolution of transition metal ions (from the LCO-NCM cathode) into the electrolyte at elevated temperatures; as a result, the reversible capacity of the full cells reduces because of the deposition of the dissolved metal ions onto the anode. Moreover, we demonstrate possible mechanisms that account for the thermal instability of FEC in LiPF 6 -based electrolytes at elevated temperatures using model experiments.

Lithium difluorophosphate (LiDFP) as a reducible additive is employed to overcome the unsatisfactory rate capability and cycling instability of highly pressed graphite electrodes with high mass loading (8.1 mg/cm2) with a vinylene carbonate (VC)-derived surface film that hampers the charge transport at the graphite–electrolyte interface at high rates. Our investigation reveals that LiDFP modifies the surface chemistry induced by VC and makes a more ionically conductive surface film on graphite, ensuring good rate capability. Keywords: Lithium–ion battery, Graphite, Anode, Electrolyte, Additive

Lithium difluoro(oxalato)borate (LiFOB) is investigated as an additive for enhancing the electrochemical performance of high-voltage lithium cobalt oxide (LiCoO2, LCO)/lithium nickel manganese cobalt oxide (LiNi0.6Co0.2Mn0.2O2, NMC) cathodes and high-capacity silicon/graphite (Si-C) anodes. LCO-NMC/Si-C full cells with a LiFOB additive have been found to exhibit improved high temperature electrochemical performance. To confirm the effects of LiFOB on the cathode and the anode, the surface chemistry of the anodes and cathodes cycled in electrolytes with and without the LiFOB additive are examined using ex-situ X-ray photoelectron spectroscopy (XPS). The LiFOB additive produces a LiF-based solid electrolyte interphase (SEI) on the Si-C anode and a carboxylate-based SEI on the LCO-NMC cathode.

Caenorhabditis elegans, a cholesterol auxotroph, showed defects in larval development upon cholesterol starvation (CS) in a previous study. To identify cholesterol-responsive proteins likely responsible for the larval arrest upon CS, a comparative proteomic analysis was performed between C. elegans grown in normal medium supplemented with cholesterol (CN) and those grown in medium not supplemented with cholesterol (cholesterol starvation, CS). Our analysis revealed significant change (more than 2.2-fold, p < 0.05) in nine proteins upon CS. Six proteins were down-regulated [CE01270 (EEF-1A.1), CE08852 (SAMS-1), CE11068 (PMT-2), CE09015 (ACDH-1), CE12564 (R07H5.8), and CE09655 (RLA-0)], and three proteins were up-regulated [CE29645 (LEC-1), CE16576 (LEC-5), and CE01431 (NEX-1)]. RNAi phenotypes of two of the down-regulated genes, R07H5.8 (adenosine kinase) and rla-0 (ribosomal protein), in CN were similar to that of larval arrest in CS, and RNAi of a down-regulated gene, R07H5.8, in CS further enhanced the effects of CS, suggesting that down-regulation of these genes is likely responsible for the larval arrest in CS. All three up-regulated genes contain putative DAF-16 binding sites and mRNA levels of these three genes were all decreased in daf-16 mutants in CN, suggesting that DAF-16 activates expression of these genes.

The cross-linkable copolymers (SHQx-TFVys) with varying degrees of sulfonation (DS) from 70 to 95% were prepared from potassium-2,5-dihydroxybenzenesulfonate (SHQ), decafluorobiphenyl (DFBP), and 4-(trifluorovinyloxy)-biphenyl-2,5-diol (TFVOH) as a cross-linkable moiety. To develop a highly stable polymer electrolyte membrane (PEM) for application in polymer electrolyte fuel cells (PEFC)s, cross-linked membranes were prepared by chemical cross-linking. The cross-linked membranes were synthesized by varying the amount of TFVOH (5–30 mol %) in order to achieve desirable PEM properties. The structures of the cross-linkable monomer and polymers were investigated by 1H and 19F NMR and FT-IR spectra. The cross-linked membranes exhibited good glass transition temperature and thermal stability up to 239–271 °C and 290–312 °C, respectively. The crosslinked membranes (DS range 80–95%) exhibited higher proton conductivity(0.098–0.151 S/cm) than Nafion 212 (0.092 S/cm). Moreover, all membranes possessed lower methano...

Crosslinked (C-ESFx-BP) and non-crosslinked (N-ESFx-BP) sulfonated poly(arylene ether) (SPAE) membranes containing high fluorine contents were prepared as a function of the degree of sulfonation (DS) and evaluated for use as a highly potential chlorine-resistant reverse osmosis (RO) membrane. C-ESFx-BP membranes were obtained by covalent crosslinking among ethynyl end groups of the polymer chains via thermal curing. Both C-ESFx-BP and N-ESFx-BP membranes show the increase in NaCl rejection with decreasing DS, while water permeability declines due to the decrease of hydrophilicity. In particular, C-ESF70-BP membrane showed excellent salt (NaCl) rejection up to 98.4% compared with that of N-ESF70-BP membrane of 90.3% but showed slightly lower water permeability of 0.6 L μm/m2 h bar than that of 0.8 L μm/m2 h bar for N-ESF70-BP. Moreover, these C-ESFx-BP and N-ESFx-BP membranes displayed the long-term stability longer than 30 days during the operation condition under high acidic chlorine concentration of NaOCl 4000 ppm unlike commercial PA membranes which are unstable under the chlorine treatment. The stability comparison between them were observed by ATR-IR, retention ratio of molecular weight (RRMW), contact angle and X-ray photoelectron spectroscopy (XPS).

ABSTEACT: IFE-1 is one of the five C. elegans homologs of eIF4E, which is the mRNA 5' cap-binding component of the translation initiation complex eIF4F. Depletion of IFE-1 causes defects in sperm, suggesting that IFE-1 regulates a subset of genes required for sperm functions. To further understand the molecular function of IFE-1, proteomic analysis was performed to search for sperm proteins that are downregulated in ife-1(ok1978); fem-3(q20) mutants relative to the fem-3(q20) control. The fem-3(q20) mutant background was used because it only produces sperm at restrictive temperature. Total worm proteins were subjected to 2D-DIGE, and differentially expressed protein spots were further identified by MALDI-TOF mass spectrometry. Among the identified proteins, GSP-3 and Major Sperm Proteins (MSPs) were found to be significantly down-regulated in the ife-1(ok1978) mutant. Moreover, RNAi of gsp-3 caused an ife-1-like phenotype. These results suggest that IFE-1 is required for efficient expression of some sperm-specific proteins, and the fertilization defect of ife-1 mutant is caused mainly by a reduced level of GSP-3.

New series of ethynyl-terminated sulfonated-fluorinated poly(arylene ether)s (ESF-6Fs) were synthesized via nucleophilic aromatic substitution reaction (SNAr) from potassium 2,5-dihydroxybenzenesulfonate (SHQ), 4,4′-(hexafluoroisopropylidene)diphenol (6FBPA), and decafluorobiphenyl (DFBP), followed by the reaction with 3-ethynylphenol. The cross-linked ESF-6F membranes exhibited high glass-transition temperatures in the range of 258−276 °C and good thermal degradation temperatures in the range of 308−328 °C. To optimize the proton conductivity and water uptake of the cross-linked ESF-6F membranes, various volume-related parameters (length-scaled parameters) were introduced. Using those parameters, the proton conductivity and water uptake of the cross-linked ESF-6F membranes were compared with sulfonated poly(arylene ether sulfone) random copolymer (BPSH), Nafion membrane, and another cross-linked membrane. In addition, the proton conductivity of optimized ESF-6F membrane was observed as a function of rela...

Treatment of Caenorhabditis elegans with apigenin, 5,7,4′-trihydroxyflavone, induces larval growth inhibition. To understand the molecular basis of apigenin-induced larval growth inhibition, the effects of apigenin on DAF-16 activity were examined. DAF-16 was activated through nuclear translocation and the mRNA level of sod-3, one of the known DAF-16 target genes, was increased upon apigenin treatment. DAF-16 activity was required for the growth inhibition, since the larval growth retardation upon apigenin treatment was suppressed in daf-16 mutants. These results indicate that apigenin acts as a stressor that activates DAF-16, which in turn inhibits larval growth.

This paper demonstrates the optimization of proton conductivity and water uptake for cross-linkable polymer electrolytes through synthesis and characterization of end-group cross-linkable sulfonated poly(arylene ether) copolymers. The extent of reaction of cross-linking was controlled by reaction time resulting in a series of polymers with two, independent tunable parameters, degree of sulfonation (DS) and degree of cross-linking (DC). For the polymers presented, cross-linking improved proton conductivity while reducing water uptake, an uncommon trend in polymer electrolytes where water is critical for proton conduction. Other trends relating to changes are reported and the results yield insight into the role of DS and DC and how to optimize electrochemical properties and performance of polymer electrolytes through these tunable parameters. Select polymer electrolytes were tested in fuel cells where performance and durability with accelerated relative humidity cycling were compared with Nafion ® .

Side chain crosslinked (C-SFPEx-CMy) sulfonated poly(arylene ether) (SPAE) membranes containing fluorine moiety with varying degree of sulfonation (DS) were prepared and evaluated for use as a thin-film composite membrane for seawater desalination. C-SFPEx-CMy membranes were obtained by covalent crosslinking among ethynyl groups at the polymer side chain through thermal curing. The crosslinked network structure suppressed the water uptake and swelling ratio. A novel type of composite membranes (TC-SFPEx-CMy) were prepared side chain crosslinked SPAE layer containing fluorine moiety on top of PET non-woven with epoxy resin as bonding agent. TC-SFPEx-CMy show the increase in NaCl rejection as DS decreases from 30% to 70%. NaCl rejection of the membranes increased with increasing corsslinking moiety (CM) while water permeability decreases due to the crosslinked net work structure. Particularly, crosslinked membrane of 30 mol % of CM could enhance the salt (NaCl) rejection property up to 85.3 % as compared to...

Crosslinkable sulfonated poly(arylene ether ketone) copolymers with various degrees of sulfonation (DS) were prepared and evaluated for use as proton exchange membranes (PEM). The copolymers were synthesized via step growth polymerization using 2,8-dihydroxynaphthalene-6-sulfonated salt (2,8-DHNS-6), 4,4′-(hexafluoroisopropylidene) diphenol (6F-BPA), 4,4′-biphenol (BP), and 4,4′-difluorobenzophenone (DFBP). 1 H NMR and FTIR-ATR spectra confirmed the structure of the copolymers and were also used to determine the obtained DS values of the copolymers. Crosslinked membranes were obtained by thermal curing of the crosslinkable copolymers. The membranes formed a crosslinking network structure via covalent bonding. The glass transition temperatures ( T g ) of the crosslinked membranes were determined by differential scanning calorimetry (DSC) and ranged from 208 to 258 °C. The decomposition temperatures ( T d ) of the membranes ranged from 309 to 325 °C for acid forms. The resulting membranes were characterized via an evaluation of their essential membrane properties, such as ion exchange capacity (IEC), water uptake, and proton conductivity. The performance of the membranes was found to be dependent on the DS and IEC.

End-group cross-linkable sulfonated poly(arylene ether) polymer (E-SFQK) was synthesized via direct polymerization of potassium 2,5-dihydroxybenzenesulfonate (SHQ) and decafluorobiphenyl (DFBP), followed by a reaction with ethynylphenol (EP). The cross-linking reaction of the ethynyl end group of E-SFQK was performed at 250 °C. After cross-linking, proton conductivity, water uptake, and swelling ratio of cross-linked membrane decreased from 0.16 (noncross-linked membrane) to 0.13 S/cm, from 86% to 42%, and from 31% to 13%, respectively. The effect of cross-linking time on proton conductivity, water uptake, and swelling ratio were also investigated. Methanol permeability of cross-linked membrane was compared with Nafion 117 due to solubility of noncross-linked membranes in methanol. The cross-linked membrane performed better, with a methanol permeability of 88 × 10−8 cm2/s, as compared with 154 × 10−8 cm2/s for Nafion 117. The cross-linked membrane also exhibited improved chemical resistance and oxidative ...

Novel sulfonated poly(arylene ether) copolymers containing cross-linking moiety and fluorine atoms were prepared for proton exchange membranes of fuel cells. The copolymers were synthesized using potassium 2,5-dihydroxybenzenesulfonate (SHQ), 4,4′-(hexafluoroisopropylidene)diphenol (6F-BPA), decafluorobiphenyl (DFBP), and 1-ethynyl-2,4-difluorobenzeneand (CM) as a cross-linking moiety through polycondensation. The chemical structures of the cross-linkable copolymers were analyzed by 1H NMR, 19F NMR, and FTIR-ATR spectra. Cross-linked membranes are obtained by thermal curing of the cross-linkable copolymers. The thermal properties of the cross-linked membranes were characterized by TGA and DSC. Intrinsic viscosity and gel fraction were also evaluated in order to measure the molecular weight and cross-linking density, respectively. The cross-linked network structure greatly suppressed the water uptake and swelling of the cross-linked membrane. The proton conductivity and methanol permeability of the membran...

As a novel class of proton exchange membrane (PEM) materials for application in fuel cells, sulfonated poly(arylene ether ketone)s (SPAEK-BPs) were prepared by polycondensation via a nucleophilic substitution reaction followed by post-sulfonation. In this way, SPAEK-BPs with different degrees of sulfonation (DS) were quantitatively synthesized via the use of chlorosulfonic acid as the sulfonating agent. It was discovered that only one sulfonic acid group can be selectively introduced without degradation per each repeating unit of polymer due to requirements for controlling reaction conditions such as reaction time and temperature. In this study, the experimentally observed DS were close to the theoretical values expected from the monomer ratios. The glass transition temperatures ( T g 's) and decomposition temperatures ( T d 's) of the polymers varied from 167 to 213 and 298 to 343 °C, respectively. In addition, the proton conductivities of the SPAEK-BP membranes exhibited up to a maximum of about 0.083 S/cm at 25 °C and 0.098 S/cm at 80 °C.

The purpose of this study was to improve the performance of a small gamma camera, utilizing a NaI(Tl) plate and a 5" position sensitive PMT. We attempted to build a NaI(Tl) plate crystal system which retained all its advantages, while at the same time integrating some of the advantages inherent in an array-type scintillation crystal system. Flood images were obtained with a lead hole mask, and position mapping was performed by detecting hole positions in the flood image. Energy calibration was performed using the energy spectra obtained from each hole position. Flood correction was performed using a uniformity correction table containing the relative efficiency of each image element. The spatial resolution was improved about 16% after correction at the centre field of view. Resolution deterioration at the outer field of view (OFOV) was considerably ameliorated, from 6.7 mm to 3.2 mm after correction. The sensitivity at the OFOV was also increased after correction, from 0.7 cps microCi(-1) to 2.0 cps microCi(-1). The correction also improved uniformity, from 5.2% to 2.1%, and linearity, from 0.5 mm to 0 mm. The results of this study indicate that the revised correction method can be employed to considerably improve the performance of a small gamma camera using a NaI(Tl) plate-type crystal. This method also provides high spatial resolution and linearity, like array-type crystals do, while retaining the specific advantages of plate-type crystals.

The purpose of this study is to improve the performances of a small gamma camera using position sensitive PMT (PSPMT) by applying position mapping, energy calibration, and flood correction. The small gamma camera consists of a 5" PSPMT coupled with either CsI(Tl) array or NaI(Tl) plate crystals. Flood images were obtained intrinsically in CsI(Tl) array system and with lead hole mask in NaI(Tl) plate system. The position mapping was performed by locating crystal arrays and hole positions in the two systems. The energy calibration was performed using energy discrimination table for each pixel array or for each hole position. The flood correction was performed using a uniformity correction table containing the relative efficiency of each image element. The resolution of the CsI(Tl) array system remained similar before and after corrections. On the other hand, the resolution of the NaI(Tl) plate system was improved about 16% after correction. The uniformity and linearity improved 33.9% to 11.6% and 0.5 mm to 0 mm, respectively, in the CsI(Tl) array system. The corrections more effectively improve the uniformity and linearity in the NaI(Tl) plate system, 21.3% to 9.2% and 0.5 mm to 0 mm, respectively. Furthermore, the resolution deterioration observed in the NaI(Tl) plate system at the outer part of FOV, was considerably diminished after the corrections. The results of this study indicate that the correction algorithms considerably improve the performances of a small gamma camera and the performance gain is more prominent in the system employing a plate type crystal.