Solution-Processable Low-Voltage and Flexible Floating-Gate Memories Based on an n‑Type Polymer Semiconductor and High‑<i>k</i> Polymer Gate Dielectrics

High-performance low-voltage flash memories based on organic floating-gate field-effect transistors are prepared by a solution process for the first time. Transistors with a high-mobility n-type polymer semiconductor, poly­{[<i>N</i>,<i>N</i>^′-bis­(2-octyldodecyl)­naphthalene-1,4,5,8-bis­(dicarboximide)-2,6-diyl]-<i>alt</i>-5,5′-(2,2′-bithiophene)}, and a high-<i>k</i> polymer gate dielectric, poly­(vinylidene fluoride–trifluoroethylene–chlorofluoroethylene) (<i>k</i> ≈ 60), are successfully fabricated on flexible substrates. A thin layer of Au nanoparticles is embedded in the gate dielectric, which can store injected charge from the channel and result in a memory effect. The organic memories demonstrate high carrier mobilities (>0.3 cm²/(V s)), low program/erase voltages (±6 V), little degradation after 10⁵ program/erase cycles, and good retention after 10⁵ s, which suggest great promise in the application of nonvolatile memories in flexible electronics

Halobenzoquinone-Induced Alteration of Gene Expression Associated with Oxidative Stress Signaling Pathways

Halobenzoquinones (HBQs) are emerging disinfection byproducts (DBPs) that effectively induce reactive oxygen species and oxidative damage in vitro. However, the impacts of HBQs on oxidative-stress-related gene expression have not been investigated. In this study, we examined alterations in the expression of 44 genes related to oxidative-stress-induced signaling pathways in human uroepithelial cells (SV-HUC-1) upon exposure to six HBQs. The results show the structure-dependent effects of HBQs on the studied gene expression. After 2 h of exposure, the expression levels of 9 to 28 genes were altered, while after 8 h of exposure, the expression levels of 29 to 31 genes were altered. Four genes (<i>HMOX1</i>, <i>NQO1</i>, <i>PTGS2</i>, and <i>TXNRD1</i>) were significantly upregulated by all six HBQs at both exposure time points. Ingenuity pathway analysis revealed that the Nrf2 pathway was significantly responsive to HBQ exposure. Other canonical pathways responsive to HBQ exposure included GSH redox reductions, superoxide radical degradation, and xenobiotic metabolism signaling. This study has demonstrated that HBQs significantly alter the gene expression of oxidative-stress-related signaling pathways and contributes to the understanding of HBQ-DBP-associated toxicity

Emerging Disinfection Byproducts, Halobenzoquinones: Effects of Isomeric Structure and Halogen Substitution on Cytotoxicity, Formation of Reactive Oxygen Species, and Genotoxicity

Halobenzoquinones (HBQs) are a structurally diverse class of water disinfection byproducts. Here, we report a systematic study on the effects of isomeric structure and the type and number of halogen substitutions of HBQs on their cytotoxicity, formation of reactive oxygen species (ROS), and genotoxicity. Dynamic responses and IC₅₀ histograms were obtained using real-time cell analysis, clearly ranking the cytotoxicity of the HBQs in Chinese hamster ovary (CHO-K1) cells. Strong isomeric structure effects were shown with 2,5-HBQ isomers inducing greater cytotoxicity than their corresponding 2,6-HBQ isomers (<i>P</i> < 0.05). HBQ-halogen substitution groups also influence cytotoxicity, as cytotoxicity increases across the dihalogenated HBQs: iodo- > bromo- > chloro-HBQs (<i>P</i> < 0.05). Determination of HBQ-induced ROS further supports isomeric structure and halogen substitution effects. HBQ-induced genotoxicity was shown as increased levels of 8-hydroxy-2′-deoxyguanosine and p53 protein. Pearson correlation analysis of the HBQ toxicity measurements with their physicochemical parameters demonstrates that dipole moment and the lowest unoccupied molecular orbital energy are two major structural influences on toxicity (<i>r</i> = −0.721 or −0.766, <i>P</i> < 0.05). Dipole moment also correlates with isomer toxicity. This study suggests that formation and occurrence of highly toxic iodo-HBQs and 2,5-HBQs warrant further investigation to fully assess the impact of HBQs in drinking water

Interconversion between Ruthenacyclohexadiene and Ruthenabenzene: A Combined Experimental and Theoretical Study

Treatment of ruthenabenzene [(C₉H₆NO)­Ru­{CC­(PPh₃)­CHC­(PPh₃)­CH}­(C₉H₆NO)­(PPh₃)]­Cl₂ (<b>1</b>) with NaBH₄ produces the first ruthenacyclohexa-1,4-diene [(C₉H₆NO)­Ru­{CC­(PPh₃)­CH₂C­(PPh₃)­CH}­(C₉H₆NO)­(PPh₃)]Cl (<b>2</b>), which was fully characterized. Under an oxygen atmosphere, complex <b>2</b> can easily convert to complex <b>1</b>. DFT calculations were carried out to rationalize the high regioselectivity in the reaction of the ruthenabenene <b>1</b> with NaBH₄ and the interconversion between <b>1</b> and <b>2</b>

Pulse-Reverse Electrodeposition and Micromachining of Graphene–Nickel Composite: An Efficient Strategy toward High-Performance Microsystem Application

Graphene reinforced nickel (Ni) is an intriguing nanocomposite with tremendous potential for microelectromechanical system (MEMS) applications by remedying mechanical drawbacks of the metal matrix for device optimization, though very few related works have been reported. In this paper, we developed a pulse-reverse electrodeposition method for synthesizing graphene–Ni (G–Ni) composite microcomponents with high content and homogeneously dispersed graphene filler. While the Vickers hardness is largely enhanced by 2.7-fold after adding graphene, the Young’s modulus of composite under dynamic condition shows ∼1.4-fold increase based on the raised resonant frequency of a composite microcantilever array. For the first time, we also demonstrate the application of G–Ni composite in microsystems by fabricating a Si micromirror with the composite supporting beams as well as investigate the long-term stability of the mirror at resonant vibration. Compared with the pure Ni counterpart, the composite mirror shows an apparently lessened fluctuations of resonant frequency and scanning angle due to a suppressed plastic deformation even under the sustaining periodic loading. This can be ascribed to the reduced grain size of Ni matrix and dislocation hindering in the presence of graphene by taking into account the crystalline refinement strengthen mechanism. The rational discussions also imply that the strong interface and efficient load transfer between graphene layers and metal matrix play an important role for improving stiffness in composite. It is believed that a proper design of graphene–metal composite makes it a promising structural material candidate for advanced micromechanical devices

Multidrug Resistance Protein 4 (MRP4/ABCC4) Protects Cells from the Toxic Effects of Halobenzoquinones

Halobenzoquinones (HBQs) are frequently detected disinfection byproducts (DBPs) in treated water. Recent studies have demonstrated that HBQs are highly cytotoxic and capable of inducing the generation of reactive oxygen species (ROS) and depleting cellular glutathione (GSH). Multidrug resistance proteins (MRPs/ABCCs) are known to play a critical role in the elimination of numerous drugs, carcinogens, toxicants, and their conjugated metabolites. In general, little is known about the roles of transporters in DBP toxicity. Here, we hypothesize that MRPs may play roles in the detoxication of HBQs. To test this hypothesis, we used human embryonic kidney 293 (HEK293) cells stably expressing MRPs (MRP1, 3, 4, and 5) and HEK293 cells with empty vector (HEK-V) to examine the comparative cytotoxicity of four HBQs: 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), 2,6-dibromo-1,4-benzoquinone (2,6-DBBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (DCMBQ), and 2,3,6-trichloro-1,4-benzoquinone (TriCBQ). The cytotoxicity (IC₅₀) of the four HBQs in HEK-MRP1, -MRP3, -MRP4, and -MRP5 cells and the control HEK-V cells clearly showed that MRP4 had the most significant effect on reducing the toxicity of the four HBQs. To further support MRP4-mediated detoxication of HBQs, we examined the HBQ-induced ROS levels in HEK-MRP4 and HEK-V cells. ROS levels were significantly reduced in HEK-MRP4 cells compared with HEK-V cells after HBQ treatment. Furthermore, it was found that MRP4-mediated detoxication of the HBQs was GSH dependent, as the cytotoxicity of the HBQs was increased in GSH-depleted HEK-MRP4 cells in comparison to HEK-MRP4 cells. The GSH-dependent protection of cells from HBQs supports the possibility of HBQ–GSH conjugate efflux by MRP4. This study demonstrates a role for MRP4 in cellular protection against HBQ DBP-induced toxicity and oxidative stress

Quantum Dots Based Mesoporous Structured Imprinting Microspheres for the Sensitive Fluorescent Detection of Phycocyanin

Phycocyanin with important physiological/environmental significance has attracted increasing attention; versatile molecularly imprinted polymers (MIPs) have been applied to diverse species, but protein imprinting is still quite difficult. Herein, using phycocyanin as template via a sol–gel process, we developed a novel fluorescent probe for specific recognition and sensitive detection of phycocyanin by quantum dots (QDs) based mesoporous structured imprinting microspheres (SiO₂@QDs@ms-MIPs), obeying electron-transfer-induced fluorescence quenching mechanism. When phycocyanin was present, a Meisenheimer complex would be produced between phycocyanin and primary amino groups of QDs surface, and then the photoluminescent energy of QDs would be transferred to the complex, leading to the fluorescence quenching of QDs. As a result, the fluorescent intensity of the SiO₂@QDs@ms-MIPs was significantly decreased within 8 min, and accordingly a favorable linearity within 0.02–0.8 μM and a high detectability of 5.9 nM were presented. Excellent recognition specificity for phycocyanin over its analogues was displayed, with a high imprinting factor of 4.72. Furthermore, the validated probe strategy was successfully applied to seawater and lake water sample analysis, and high recoveries in the range of 94.0–105.0% were attained at three spiking levels of phycocyanin, with precisions below 5.3%. The study provided promising perspectives to develop fluorescent probes for convenient, rapid recognition and sensitive detection of trace proteins from complex matrices, and further pushed forward protein imprinting research

Eigenvector centrality coefficients of individuals based on HWI and DAI.

<p>Individuals of the same sex are presented from left to right (males for the first four and females for the next eight) in the descending order in hierarchy.</p

RvD1 inhibited phosphorylation of JNK and the Smad3 linker region but not Smad3 c-terminal phosphorylation in the obstructed kidney.

<p>Mice underwent sham or unilateral ureteral obstruction (UUO) surgery. Two days after UUO surgery, mice received intraperitoneal injections of RvD1 for another two days and were killed on day 4. (A) Immunoprecipitation (IP) of Smad3 followed by Western Blotting (WB) identified phosphorylation of the Smad3 C-terminal domain (p-C-Smad3) and linker region (p-T179 and p-S208) following unilateral ureteric obstruction (UUO) compared to the sham operated control. In addition, Smad3 IP pulled down phosphorylated JNK (p-JNK). (B) Western blot identifying phosphorylation of the Smad2 C-terminal domain (p-C-Smad2), total Smad2, total Smad4 and GAPDH. (C) Quantification of the relative levels of abundance of p-JNK, p-T179, p-S208, p-C-Smad3 compared to total Smad3, p-C-Smad2 compared to total Smad2 and total Smad4 compared to GAPDH. Data are mean ±SD from groups of 6 mice and analysis by one-way ANOVA with post hoc analysis with Tukey's multiple comparison test. *** <i>p</i>&lt;0.001; N.S., not significant.</p

Origin of Adamantanes and Diamantanes in Marine Source Rock

Thermal maturation-related variations in the yields of lower diamondoids (adamantanes and diamantanes) in source rock were investigated by thermal simulation experiments based on a marine shale and kerogens obtained from the shale via isolation and artificial maturation, representing different maturity stages of the oil generation window. The simulations show that lower diamondoids are formed and destroyed during thermal maturation of the shale. For example, adamantanes are generated mainly in the maturity range of 0.8%–1.8% EasyRo, then they begin to degrade at 1.8% EasyRo. Diamantanes are produced mainly during the maturity range of 1.0%–2.2% EasyRo and begin to degrade at 2.2% EasyRo. The mineral matrix of shale may have a strong effect on the destruction of diamondoids, leading to a reduction in the peak yield and a reduction in the maturity level corresponding to the peak yield of diamondoids. A comparison of the diamondoid yields from four kerogens at different maturity levels indicates that the lower diamondoids are derived mainly from secondary cracking of extractable organic matter (bitumens) occurring in the source rock. For instance, at the peak stage of adamantane formation (2.1% EasyRo), 75.6% of the total adamantanes is generated from the cracking of bitumens and the remaining 24.4% is from the primary cracking of kerogens. Similarly, the yield of diamantanes generated from the secondary cracking of bitumens accounts for 87.8% of the total diamantanes at the peak stage of diamantane formation (2.5% EasyRo). Almost no diamondoids are detected in the pyrolysates of more mature kerogen (1.3%EasyRo), suggesting that 1.3% EasyRo is the upper limit of maturity for the generation of diamondoids from kerogen. Diamondoid isomerization ratios are maintained at relatively constant levels during the formation stage of diamondoids, whereas a linear correlation with maturity occurs during the destruction stage, suggesting that isomerization ratios of diamondoids are controlled by their thermal stability just in the destruction stage and are unaffected by hydrocarbon generation and expulsion of source rock at early thermal stages. This finding indicates that these diamondoid indices are a potential tool for evaluating the thermal maturity of source rocks at highly mature stages