Local Gromov-Witten Invariants are Log Invariants

We prove a simple equivalence between the virtual count of rational curves in the total space of an anti-nef line bundle and the virtual count of rational curves maximally tangent to a smooth section of the dual line bundle. We conjecture a generalization to direct sums of line bundles.Comment: 15 pages, version accepted for publication in Advances in Mathematic

Effects and Mechanism of Metal Chloride Salts on Pretreatment and Enzymatic Digestibility of Corn Stover

The effects of three metal chlorides including FeCl₃, CuCl₂, and AlCl₃ on corn stover biomass pretreatment and enzymatic hydrolysis were studied under lower severity conditions (reaction temperature of 150–160 °C, salt concentration of 0.075–0.125M, and reaction time of 10 min). The results were compared with dilute sulfuric acid pretreatment at the same conditions. The maximum monomeric xylose yields were observed to be 93 and 94 wt % when CuCl₂ and FeCl₃ were used in the pretreatment at 160 °C for 10 min at 0.125 M concentrations, which were higher than the sulfuric acid pretreatment yields at the same reaction conditions. However, monomeric xylose yield for corn stover pretreated with AlCl₃ was observed to be 8 wt % at the same condition. This could be explained by isomerization of xylose to xylulose and subsequent dehydration into furfural. However, enzymatic digestibility yields for the three metal chloride pretreated samples at 160 °C were greater than 92 wt % . These yields were higher than sulfuric acid pretreated samples at the same reaction conditions. The overall formation of fermentation inhibitor products for samples pretreated with CuCl₂ and FeCl₃ was observed to be similar to the control samples (pretreated with sulfuric acid at the same conditions)

Enhanced Photoelectrocatalytic Activity of a Novel Bi₂O₃–BiPO₄ Composite Electrode for the Degradation of Refractory Pollutants under Visible Light Irradiation

A novel Bi₂O₃–BiPO₄ composite electrode was successfully synthesized by the method of electrophoretic deposition, electrodeposition, and calcination in a proper sequence. The prepared electrodes were characterized by X-ray diffractometry (XRD) and scanning electronic microscopy (SEM). Linear sweep voltammetry (LSV) and photocurrent decay curves measurement indicated that the Bi₂O₃–BiPO₄ composite electrode exhibited better photoelectrochemical (PEC) activity than either pure Bi₂O₃ or BiPO₄ electrode. Incident photon to current conversion efficiency (IPCE) and electrochemical impedance spectra (EIS) measurements revealed that the composite electrode significantly improved the efficiency of charge transfer and decreased the recombination of photogenerated charges. Furthermore, the composite electrode also displayed higher efficiency and stability in the PEC degradation of organic pollutants. The <i>p</i>–<i>n</i> junction structure of the Bi₂O₃–BiPO₄ composite electrode was most likely responsible for the enhanced PEC activity

Fungal Biotransformation of Insoluble Kraft Lignin into a Water Soluble Polymer

Low substrate solubility and slow decomposition/biotransformation rate are among the main impediments for industrial scale lignin biotreatment. The outcome and dynamics of kraft lignin biomodification by basidiomycetous fungi, <i>Coriolus versicolor</i>, were investigated in the presence of dimethyl sulfoxide (DMSO). The addition of 2 vol % DMSO to aqueous media increased the lignin solubility up to 70%, while the quasi-immobilized fungi (pregrown on agar containing kenaf biomass) maintained their ability to produce lignolytic enzymes. Basidiomycetous fungi were able to grow on solid media containing both 5–25 g/L lignin and up to 5 vol % DMSO, in contrast to no growth in liquid media as a free suspended culture. When a fungal culture pregrown on agar was used for lignin treatment in an aqueous medium containing 2–5% DMSO with up to 25 g/L lignin, significant lignin modification was observed in 1–6 days. The product analysis suggests that lignin was biotransformed, rather than biodegraded, into an oxygenated and cross-linked phenolic polymer. The resulting product showed the removal of phenolic monomers and/or their immediate precursors based on gas chromatography and thermal desorption–pyrolysis–gas chromatography–mass spectrometry analyses. Significant intramolecular cross-linking among the reaction products was shown by thermal carbon analysis and ¹H NMR spectroscopy. An increase in polarity, presumably due to oxygenation, and a decrease in polydispersity of the lignin treatment product compared to untreated lignin were observed while using liquid chromatography

High Strength Magnetic/Temperature Dual-Response Hydrogels for Applications as Actuators

Anisotropically structured magnetic/temperature dual-response hydrogels have great application prospects as actuators because they can exhibit controlled, complex behaviors. However, one key issue hindering the application of such hydrogels is the imbalance of the mechanical and response properties. This study used a combination of flexible chain polymers such as poly(N-isopropylacrylamide) (PNIPAM), poly(vinyl alcohol) (PVA), and polyacrylamide (PAM) to build a multinetwork structure. The introduction of TEMPO-oxidized cellulose nanofibrils (TOCNF) as a nanofiber reinforcement agent led to a key improvement to ensure a high mechanical strength by creating additional hydrogen bonding. The cross-linking density was further increased through a salting out treatment to obtain a greater mechanical strength while improving the dissipation of energy applied by external sources. The obtained temperature responsive layer featured a high tensile strength (1.97 MPa) while the magnetically responsive layer showed a high magnetization (6.1 emu/g) with a good tensile strength (0.47 MPa). The main idea of this study was in combining two hydrogel layers with different polymer network structures, with magnetic nanoparticles being dispersed within one layer, whereas the other layer was designed as temperature-sensitive. The obtained bilayer hydrogel had suitable mechanical properties (the tensile strength reaching 0.81 MPa) coupled with strong dissipation of the applied external energy and could rapidly and reversibly undergo bending deformations upon a temperature change within a narrow range, 25–37 °C (bending angle up to 160° within 5 min). With high magnetization characteristics for the magnetically responsive layer, the bilayer hydrogel could easily be driven by an external magnetic field to transport a target object, which was “grabbed” due to the gel bending. It also showed good biocompatibility, thus enabling applications in the field of invasive medical actuators

Effects of CHA on EV71 replication before or after viral infection.

<p>DMSO: EV71 infection with DMSO. CHA: EV71 infection with DMSO and CHA RD cells (5 × 10⁶) were infected with EV71 (5 MOI) and CHA (20 µg/ml) was added at the indicated time. Cell supernatants were collected at 25 h p.i. and EV71 titers were determined by a plaque forming assay. Each bar represents the mean ± S.D. of three independent experiments（** <i>p</i> < 0.01, *** <i>p</i> < 0.001).</p

EV71 infection stimulates cytokine secretion.

<p>Control: Uninfected RD cells; EV71: RD cell-infected with EV71 (MOI = 5); CHA: EV71 infection in the presence of CHA (20 µg/ml). RD cells were absorbed with EV71 for 1h, and then treated with or without CHA(20 µg/ml). Culture supernatants were collected at 8h, 12h, and 20h. The concentrations of IL-2, IL-6, IL-10, TNF-α, IFN-γ and MCP-1 were detected by luminex fluorescent technique. The data were expressed as mean ± SE from 3 independent experiments. ** <i>P</i> < 0.01 and ***<i>P</i> < 0.001 by two-way ANOVA.</p

Effects of CHA on EV71 replication.

<p>Ribavirin was used as positive control and 0.1% DMSO as negative control. Inhibitory effects of ribavirin and indicated concentration of CHA on EV71 replication were determined by a plaque reduction assay. Data were represented as mean ± S.D. of three independent experiments.</p

Effects of CHA on EV71 protein expression.

<p>EV71 infection: RD cell-infected with EV71 (MOI = 5). CHA treatment: EV71 infection in the presence of CHA (20 µg/ml). DMSO: EV71 infection treated with 0.1% DMSO. At 4 and 8h, the cell lysates were subjected to 10% SDS-PAGE and transferred to PVDF membrane to determine the level of EV71 VP1, 2A, 3C, and 3D.</p

CHA inhibits EV71 replication in RD cells.

<p>RD cells (5×10⁶) were infected with EV71 at a MOI of 5 in the presence or absence of CHA (20 µg/ml) and ribavirin (40 µg/ml). CHA and ribavirin were added with EV71 at the same time or absorbation for 1 h. Then cell supernatants were collected at 0, 4, 8,12, 16, 20, 24,28, 32 and 36 h p.i. and the viral titers were determined by a plaque forming assay. Each point represents the mean ± S.D. of three independent experiments (*** <i>p</i> < 0.001).</p