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In this paper, electronic-grade epoxidized Cardol (E-Cardol), a bifunctional reactive diluent for epoxy resin, was synthesized from Cardol and epichlorohydrin by a two-step reaction. FT-IR, NMR, and high-performance liquid chromatography have been used for structural characterization and reaction dynamic studies. A stepwise dichlorination process considering all sources of chloride has been proposed: (i) minimizing the etherification side reaction while accelerating the main reaction, (ii) driving the main etherification reaction forward in the closed-loop reaction, and (iii) applying a refining step based on the Williamson reaction. E-Cardol with a hydrolyzable chlorine content below 100 ppm and decreased viscosity (30%) was obtained. Copper corrosion experiments confirmed the enhanced anticorrosion properties of the electronic-grade E-Cardol coating. This constitutes the first report of an electronic-grade Cardol-based bifunctional reactive diluent. Our work may give a guide to the design of all of the electronic-grade bio-based reactive diluents and other epoxy resins.

The epoxidation process of soybean oil (SBO) and peracid produced by 50 wt% hydrogen peroxide (H2O2) and formic acid (FA) was studied with sulfuric acid (H2SO4) as a catalyst. Three reaction parameters, including reaction temperature, FA-to-SBO ratio, and H2O2-to-SBO ratio, were investigated, along with the combined effect on oxirane value (OV). Based on response surface methodology (RSM), the Box-Behnken design (BBD) was used to optimize the process parameters. According to the results, the calculated OV (7.34%) and the experimental OV (7.31%) were signifi cantly in agreement. The product was confi rmed as epoxidized soybean oil (ESO) by IR and NMR characterization methods. These results demonstrated the reliability of RSM to optimize the SBO reaction to produce ESO with high oxygen content.

Based on the Prileschajet reaction, formic acid (FA), hydrogen peroxide (H2O2) were selected as the oxidants and sulfuric acid (H2SO4) as the catalyst to establish the reaction model. Initially, the reaction mechanism of the system was explained by investigating the process conditions of soybean oil (SBO), and the results showed that the two-phase (oil–water) reaction system was similar to the quasi-homogeneous system. Consequently, a mathematical model of quasi-homogeneous system was established to describe the epoxidation process of SBO. Although the rate constants indicated that the formation of PFA was a decisive step of the whole system, PFA still exists as an intermediate in the system. Furthermore, the activation energy of PFA decomposition indicated the temperature sensitivity of PFA, making it prone to easy decomposition. This strongly suggests that the decomposition of PFA and its subsequent consequences are not to be treated as negligible phenomena.

Wick action is the key factor in understanding the salt weathering of porous materials. In this study, concrete discs were partially exposed to Na2SO4solution to simulate the wick action in concrete. We evaluated the effects of the relative humidity (RH), solution concentration, and pore structures (different water to cement ratios) on the solution transport mechanism based on the water evaporation rate. Interestingly, we found that lower RH and larger W/C ratio accelerated evaporation, but the higher concentration of the solution slowed it down. The micro-analyzer results of NMR and XRD confirmed that the formation of ettringite and gypsum due to chemical sulfate attack blocked the pores in the concrete, resulting in a decrease in water evaporation. Na2SO4crystallization distress was not detected in the concrete. Therefore, the solution transport process in the concrete discs could not be described by wick action.

ABSTRACTCorneal neovascularization (CRNV) is a prevalence eye disorder that affects the transparency and refraction properties of eyes. To explore the correlation between the level of Angiotensin II (Ang II) and corneal angiogenesis, the rat model of CRNV was established using alkali-burn, while the human umbilical vein endothelial cells (HUVECs) were stimulated using VEGF to induce the CRNV cells in vitro. RNA immunoprecipitation (RIP) and RNA pull-down were performed to validate the relationship between MIAT and miR-1246. The expression of MIAT and Ang II was increased, while miR-1246 was decreased in CRNV rat model. VEGF stimulation significantly promoted cell proliferation and migration of HUVECs, knockdown of MIAT dramatically reversed the effects of VEGF, while cells co-transfected with miR-1246 inhibitor obviously abolished the effect of VEGF+si-MIAT, however, enalaprilat abolished the effects of VEGF+si-MIAT+miR-1246 inhibitor. MIAT directly regulated the expression of miR-1246. In conclusion, VEGF stimulation promoted cell proliferation and migration of HUVECs mainly through regulating MIAT/miR-1246/ACE.

In the tunnels of the Cheng-Kun Railway in China, concrete failure can usually be observed from the effect of sulfates. A field investigation was conducted to analyze the concrete damage mechanism by means of XRD, IC, AAS and EPMA. The results showed that (1) large amounts of Na2SO4were generated on the surface layer of the concrete lining, causing concrete detachment layer by layer; (2) the concrete lining in contact with air had been neutralized to more than 50mm in depth, and the cement hydration products had been converted into CaCO3; (3) ettringite and gypsum, the products of chemical sulfate attack, were also detected in the neutralized concrete lining. This analysis of a field case concluded that Na2SO4crystallization caused the detachment of the surface layer of the concrete lining, and the chemical sulfate attack occurred in the inner part of the concrete lining.

Interfacial materials play a critical role in photoelectric conversion properties as well as the anomalous hysteresis phenomenon of the perovskite solar cells (PSCs). In this article, a water-soluble polythiophene PTEBS was employed as a cathode interfacial material for PSCs. Efficient energy level aligning and improved film morphology were obtained due to an ultrathin coating of PTEBS. Better ohmic contact between the perovskite layer and the cathode also benefits the charge transport and extraction of the device. Moreover, less charge accumulation at the interface weakens the polarization of the perovskite resulting in a relatively quick response of the modified device. The ITO/PTEBS/CH3NH3PbI3/spiro-MeOTAD/Au cells by an all low-temperature process achieved power conversion efficiencies of up to 15.4% without apparent hysteresis effect. Consequently, the utilization of this water-soluble polythiophene is a practical approach for the fabrication of highly efficient, large-area, and low-cost PSCs and compatible with low-temperature solution process, roll-to-roll manufacture, and flexible application.

With the rapid expansion of China’s economy, China’s music industries have shown rapid growth, and new companies have entered the marketplace. As these companies have had little pre-existing experience with the music industry—not to mention that music industry is a relatively new concept in China—the expansion has been not only rapid but also disordered and chaotic. One component of a mature music industry are collective rights management or performing rights organizations, which are independent non-profit social organizations that collect license fees on behalf of copyright holders (songwriters, composers, music publishers) and distribute these fees as royalties to members whose works have been performed. In this “In Focus” report, we compare and contrast the state of collective rights management in China, the United States, and Japan. Recognizing that China’s representative, the Music Copyright Society of China, is new to the scene, we should not be terribly surprised that it is lagging behind the other countries. Herein, we cite various areas where improvement is necessary so that China’s collective rights management can be in part with its international peers.

Genetic mutations in HSF4 cause congenital cataracts. HSF4 exhibits both positive and negative regulation on the transcription of heat shock and non-heat shock proteins during lens development, and its activity is regulated by posttranslational modifications. Biotin is an essential vitamin that regulates gene expression through protein biotinylation. In this paper, we report that HSF4b is negatively regulated by biotinylation. Administration of biotin or ectopic bacterial biotin ligase BirA increases HSF4b biotinylation at its C-terminal amino acids from 196 to 493. This attenuates the HSF4b-controlled expression of αB-crystallin in both lens epithelial cells and tested HEK293T cells. HSF4b interacts with holocarboxylase synthetase (HCS), a ubiquitous enzyme for catalyzing protein biotinylation in mammal. Ectopic HA-HCS expression downregulates HSF4b-controlled αB-crystallin expression. Lysine-mutation analyses indicate that HSF4b/K444 is a potential biotinylation site. Mutation K444R reduces the co-precipitation of HSF4b by streptavidin beads and biotin-induced reduction of αB-crystallin expression. Mutations of other lysine residues such as K207R/K209R, K225R, K288R, K294R and K355R in HSF4's C-terminal region do not affect HSF4's expression level and the interaction with streptavidin, but they exhibit distinct regulation on αB-crystallin expression through different mechanisms. HSF4/K294R leads to upregulation of αB-crystallin expression, while mutations K207R/K209R, K225R, K288R, K255R and K435R attenuate HSF4's regulation on αB-crystallin expression. K207R/K209R blocks HSF4 nuclear translocation, and K345R causes HSF4 destabilization. Taken together, the data reveal that biotin maybe a novel factor in modulating HSF4 activity through biotinylation.

The purpose of the present study was to determine the best cholinergic neuronal differentiation method of rhesus monkey bone marrow mesenchymal stem cells (BMSCs). Four methods were used to induce differentiation, and the groups were assigned accordingly: basal inducing group (culture media, bFGF, and forskolin); SHH inducing group (SHH, inducing group); RA inducing group (RA, basal inducing group); and SHH+RA inducing group (SHH, RA, and basal inducing group). All groups displayed neuronal morphology and increased expression of nestin and neuron-specific enolase. The basal inducing group did not express synapsin, and cells from the SHH inducing group did not exhibit neuronal resting membrane potential. In contrast, results demonstrated that BMSCs from the RA and SHH+RA inducing groups exhibited neuronal resting membrane potential, and cells from the SHH+RA inducing group expressed higher levels of synapsin and acetylcholine. In conclusion, the induction of cholinergic differentiation through SHH+RA was determined to be superior to the other methods.

An innovative lab-on-a-chip device based on iridium oxide (IrOx) nanowires was designed, fabricated, and developed for real-time “point-of-care” diagnostics. The turnaround time in detection and the need for expensive equipment for analysis have considverably limited rapid and “point-of-care” diagnosis. This research demonstrates the potential of IrOx nanowires toward early disease diagnosis by detecting proteins that are disease markers. The device designed is based on electrical detection of protein biomarkers wherein a single capture immunoassay is built onto a vertically aligned IrOx nanowire platform. Detection of two inflammatory proteins, C-reactive protein (CRP) and myeloperoxidase (MPO) (Calbiochem, La Jolla, CA), that are biomarkers of cardiovascular diseases is demonstrated individually and concurrently. The performance metrics of the device in response to the two biomarkers in pure form and in serum samples were evaluated and compared with standard enzyme-linked immunosorbent assay (ELISA). The methodology that has been adopted is based on measuring real-time impedance changes because of the protein binding event through electrochemical impedance spectroscopy and calibrating its change in magnitude with concentration of proteins. We have demonstrated limit of detection up to 500 pg/mL for protein MPO and I ng/mL for CRP with cross-reactivity of less than 8% of selective binding of these two inflammatory biomarkers.

An innovative lab-on-a-chip device based on iridium oxide (IrOx) nanowires was designed, fabricated, and developed for real-time “point-of-care” diagnostics. The turnaround time in detection and the need for expensive equipment for analysis have considverably limited rapid and “point-of-care” diagnosis. This research demonstrates the potential of IrOx nanowires toward early disease diagnosis by detecting proteins that are disease markers. The device designed is based on electrical detection of protein biomarkers wherein a single capture immunoassay is built onto a vertically aligned IrOx nanowire platform. Detection of two inflammatory proteins, C-reactive protein (CRP) and myeloperoxidase (MPO) (Calbiochem, La Jolla, CA), that are biomarkers of cardiovascular diseases is demonstrated individually and concurrently. The performance metrics of the device in response to the two biomarkers in pure form and in serum samples were evaluated and compared with standard enzyme-linked immunosorbent assay (ELISA). The methodology that has been adopted is based on measuring real-time impedance changes because of the protein binding event through electrochemical impedance spectroscopy and calibrating its change in magnitude with concentration of proteins. We have demonstrated limit of detection up to 500 pg/mL for protein MPO and I ng/mL for CRP with cross-reactivity of less than 8% of selective binding of these two inflammatory biomarkers.

This paper will discuss the spin on deposition of Pb5Ge3O11(PGO) on Ir and ZrO2 substrates for MFMIS and MFIS FeRAM applications. The precursors used are lead acetate trihydrate and germanium isopropoxide in di (ethylene glycol) ethyl ether. After optimizing the deposition conditions of spin speed, baking condition and annealing condition, single phase c-axis PGO has been obtained on both Ir and ZrO2 substrates. The film deposited on Ir substrate shows extremely smooth surface and very well saturated square shape hysteresis loop. The 2Pr is about 6∼8 μC/cm2, dielectric constant is about 50∼100, and the leakage current is about 3×10-6 A/cm2 at 100 kV/cm for 100-120nm thickness PGO thin film. The PGO thin film deposited on ZrO2 is also very uniform. About 0.7V memory window observed for 180nm PGO thin film with 13nm ZrO2 high-k gate dielectric at 2V sweep voltage. The leakage current is about 2.5×10-7 A/cm2 at 100 kV/cm

The first MFIS FETs PMOS using Pt/Pb5Ge3O11/ZrO2/n-Si structure has been successfully fabricated. The PGO thin film was deposited by spin on method. Single phase PGO with strong c-axis orientation and low leakage current was obtained on ZrO2 substrate. Pt was used as top electrode and the gate stack was dry etched using chlorine chemistry. Using CMOS compatible process, the integration of MFIS FETs is simple and reliable. ID-VG and ID-VD were characterized on 10 × 10 μrn (L × W) devices. The memory window obtained is about 1.3V with 200nm PGO and 13nm ZrO2. It is also found that memory window is less dependent on device sizes.

Fatigue free ferroelectric Pb5Ge3O11 (PGO) films have been prepared using metalorganic chemical vapor deposition (MOCVD). [Pb(thd)2] and [Ge(OC2H5)4] were used as the precursors for lead and germanium, respectively. The PGO films were deposited onto Ir/Ti/SiO2/Si and Pt/Ti/SiO2/Si wafers to measure their compositions, phase formation, microstructures and ferroelectric properties. The X-ray pattern showed the formation of C-axis oriented PGO films. All the PGO films showed excellent fatigue characteristics: no fatigue was observed up to 1 × 109 switching cycles. It is believed that the superior fatigue properties of these PGO films are due to the PGO lattice structure. PGO materials have large polarization along the c axis, but little or no polarization along a and b axis, thus the domain configuration is 180°. This is one reason that PGO has excellent fatigue properties, which is similar to Bi-layered oxides such as SrBi2Ta2O9 material. A typical 300-nm thick PGO film exhibited a saturated and square hysteresis loop. The remanent polarization (2Pr) and coercive field (2Ec) values at 5V were about 3.72 μC/cm2 and 67 kV/cm, respectively. The leakage current increased with increasing applied voltage, and is about 9.5 × 10-7 A/cm2 at 100 kV/cm. The maximum dielectric constant is about 35. The MOCVD PGO films can be used for single transistor memory applications.

The aim of this study was to investigate the plasma and ocular dexamethasone (DEX) pharmacokinetics characteristics of the sub-tenon microfluidic system (SMS) delivery of dexamethasone sodium phosphate (DEXP) in experimental autoimmune uveitis (EAU) rabbits. The SMS showed sustained DEX release and large amount of drug loading capacity by a miniature pump which connected with a tube that implanted into the sub-Tenon's sac of the EAU rabbit. The DEX concentrations in the plasma and different ocular compartments (cornea, aqueous humor, retina/choroid, sclera and vitreous humor) were quantified by Shimadzu LC–MS 2010 system. The SMS increased total drug delivery of DEX in ocular tissues as compared with traditional combined medication (subconjunctival injection combined with intravenous injection) in EAU rabbit. Moreover, the minimal amount of DEX was found in the blood, indicated that only a small amount of drug could enter into the bloodstream and causing minimal systematic side effect. Overall, the study provided evidence that SMS meet the large amount of drug loading capacity, continuous release drugs and moderate drug level in the EAU ocular tissue and minimal drug level in the blood, which indicated that SMS could be a feasible option for ocular application in clinical trials and maybe can replace or even discard systemic medications for the management of acute ocular inflammation disease.

We fabricated GaN light-emitting diodes with a layer of graphene as a transparent electrode. A 3-nm-thick Al layer was deposited on the graphene layer by electron-beam evaporation. This Al layer plays an important role in protecting the graphene layer during the device fabrication process. Moreover, this Al layer can also enhance the light emission of GaN light-emitting diodes through the investigation of electroluminescence spectra. The significantly improved light emission is attributed to the current expansion, the enhanced plasmonic density of states, and the decreased non-radiative recombination rate.

An Ir-Ta-O/Ta/Si structure with Ir-Ta-O as electrode and Ta as diffusion barrier layer on silicon substrate has been fabricated. The Ir-Ta-O film was deposited by reactive sputtering using separate Ir and Ta targets in oxygen ambient. Annealing results performed from 500-1000°C in oxygen ambient showed that the Ir-Ta-O film exhibited extraordinary high temperature stability. This film showed good conductivity and integrity even after 5 min annealing at 1000°C. No destructive peeling and hillock formation were observed. By using this film as bottom electrode for depositing ferroelectric SrBi2Ta2O9thin film at 800°C, good ferroelectric properties were achieved.

Lead Germanate thin films have been successfully deposited on different electrodes by a metalorganic chemical vapor deposition (MOCVD) system for the first time. Three different phases have been characterized. The single c-axis oriented Pb5Ge3O11phase has been deposited on Ir, Ir/Pt (Pt on top) and Pt electrodes respectively and shows a very uniform surface. A lead rich phase, Pb3GeO5, also was formed with a polycrystalline structure and large grain size exhibiting a very rough surface. Finally an unknown oxygen and/or lead deficient phase, which is considered here a non-stoichiometric phase of Pb5Ge3O11, appeared with a smaller interplanar spacing of about 9.4 Å compared with 10.68 Å for the Pb5Ge3O11phase. This unknown phase can co-exist with the c-axis oriented Pb5Ge3O11phase and deteriorates its ferroelectric properties. Post deposition annealing in an oxygen or oxygen plus lead ambient can recover the ferroelectric properties of this film.