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This study investigated the effectiveness of carbon adsorbents as remediation material for sediments contaminated with heavy metals and the feasibility of utilizing diffusive gradients in thin films (DGT) as a biomimetic tool to estimate the accumulation of heavy metals in Venerupis philippinaram (Manila clam). The results showed that carbon materials had significant inhibitory effects (14.0–53.0%) on the enrichment of heavy metals in organisms and the order of increasing overall inhibitory effect was: charcoal, peat, activated carbon, and biochar. There were significant correlations (P

A new strategy exploiting together the modified Riemann–Liouville fractional derivative rule and two kinds of fractional dual-function methods with the Mittag–Leffler function is presented to solve fractional nonlinear models. As an example, the space-time fractional Fokas-Lenells equation is solved by this strategy, some new exact analytical solutions including bright soliton, dark soliton, combined soliton and periodic solutions are found. The comparison of two kinds of fractional dual-function methods is also presented. These solutions exist under a constraint among parameters of nonlinear dispersion, nonlinearity and self-steepening perturbation. In order to further study the optical soliton transport and better understand the physical phenomenon behind the model, dynamical characteristics of analytical fractional soliton solutions including some graphics and analysis is provided. The role of the fractional-order parameter is studied.

With the aim to reveal the microbial community succession at various temperatures in the fermentation of Qingzhuan tea (QZT), the Illumina NovaSeq sequencing was carried out to analyze bacterial and fungal community structure in tea samples collected from the fermentation set at various temperatures, i.e., 25 °C, 30 °C, 37 °C, 45 °C, 55 °C, and room temperature. The results showed that fermentation temperature profoundly affected the microbial community succession in the QZT fermentation. Microbial richness and community diversity decreased along with the increase of fermentation temperature. Despite the differences between microorganisms and their metabolic types among various temperatures, most bacteria and fungi showed positive correlations at the genera level. Klebsiella, Paenibacillus, Cohnella, and Pantoea were confirmed as the main bacterial genera, and Aspergillus and Cyberlindnera were the main fungal genera in QZT fermentation. The microbial genera (i.e. Aspergillus, Rhizomucor, Thermomyces, Ralstonia, Castellaniella, and Vibrio) were positively correlated with fermentation temperature (P 0.05), while Klebsiella, Paenibacillus, and Aspergillus had good adaptability at different temperatures. Conversely, Pantoea and Cyberlindnera were only suitable for low temperature (≤37 °C) growth, and Thermomyces was only suitable for high temperature (37 °C) growth. Aspergillus had a significant positive correlation with tea aroma quality (r = 0.64, p 0.05). This study would help to understand the formation mechanism of QZT from microflora perspective.

The work aimed to explore effects of polytetrafluoroethylene nanoplastics on joint inhibitions of ciprofloxacin and bivalent copper on the nitrogen removal in a sequencing batch reactor and its potential mechanisms. The addition of bivalent copper and/or ciprofloxacin reduced the ammonia nitrogen elimination rate with or without polytetrafluoroethylene nanoplastics. Adsorption kinetics and thermodynamics showed the binary bivalent copper and ciprofloxacin promoted their adsorptions by polytetrafluoroethylene nanoplastics. Polytetrafluoroethylene nanoplastics enhanced combined toxicities of ciprofloxacin and bivalent copper to sludge activities and microbial community involved into nitrification and denitrification due to the adsorption of ciprofloxacin and bivalent copper by polytetrafluoroethylene nanoplastics. With or without polytetrafluoroethylene nanoplastics, bivalent copper and/or ciprofloxacin caused more obvious level changes of protein than polysaccharide. This study provides novel insights for understanding the effect of combined heavy metals and antibiotics on the performance in a sequencing batch reactor with the nanoplastics stress.

This work provides an environmental friendly route to fabricate ternary silver/silver oxide/zinc oxide (Ag/Ag2O/ZnO) photocatalyst with assistance of bovine serum albumin (BSA). The structural analysis indicates that Ag/Ag2O/ZnO photocatalyst is a 3D-flowerlike architecture. Nanoparticles composed of Ag and Ag2O in diameter about 40 nm attach on the surfaces of ZnO “petals” and form a heterojunction structure with ZnO. The ultraviolet-visible (UV–vis) spectra and photoluminescence (PL) spectra show that the obtained Ag/Ag2O/ZnO nanocomposite displays an enhanced visible-light absorption and a decreased fluorescence emission compared to that of ZnO. The photocatalytic performance of Ag/Ag2O/ZnO nanocomposite was evaluated by photocatalytic degradation of methylene blue (MB) under simulated visible light irradiation. The results indicate that Ag/Ag2O/ZnO nanocomposite exhibits better photocatalytic activity than that of single- and two-component photocatalysts including ZnO, Ag2O, TiO2 and Ag/ZnO. Ag/Ag2O/ZnO nanocomposite also has a good recycling stability and still maintains a high degradation efficiency (85%) after four recycles. The improved photocatalytic activity is credited to the synergistic effect of Ag, Ag2O and ZnO nanophases in the Ag/Ag2O/ZnO heterojunction, which results in an effective charge separation and a low recombination of photo-induced electron-hole pairs.

Aggression is one of the most serious social problems worldwide. The cognitive mechanisms of aggression have been frequently studied, and hostile attribution bias has been regarded as an important cognitive factor influencing the formation and development of aggression. However, the longitudinal relationship between hostile attribution and aggression among undergraduate students has not yet been tested, and the psychological mechanism underlying the effect of hostile attribution on aggression has not yet been explored. This study aimed to address these two issues through two studies. The Hostility subscale of the Word Sentence Association Paradigm for Hostility and the Buss-Perry Aggression Questionnaire were administered to 505 undergraduate students twice with an interval of 6 months in Study 1. The cross-lagged analyses demonstrated a reciprocal relationship between hostile attribution bias and aggression. Another 437 participants were recruited for Study 2. The analyses via structural equation modeling support the view that anger rumination plays a mediating role in the relationship between hostile attribution bias and aggression. This study expands our understanding regarding the relationship between hostile attribution bias and aggression and suggests an interaction between aggressive cognition and aggressive behavior. In addition, certain aggressive cognitive factors may predict other aggression-related cognitive factors.

The unexpected oxyamination reaction of O, ω-unsaturated alkoxyamines was found experimentally. The mechanistic issues were studied by DFT calculations. It is suggested that the reaction undergoes [3 + 2] cyclic addition, O N bond cleavage, C N reductive elimination, and the Rh N unit protonation, generating the product and regenerating the active catalyst. The nitrene Rh(V) species containing a Rh C bond rather than a Rh O bond was suggested to be involved in the reaction mechanism. Why the substrate A with X = O but not X = C undergoes oxyamination reaction was rationalized based on the suggested reaction mechanism.

A hierarchical porous carbon nanorods (HPCRs) with highly interconnected three-dimensional conductivity networks derived from metal-organic frameworks have been successfully synthesized via a simple carbonization method. The resultant HPCRs shows an stable porous structure with abundant micro/mesopore on two-dimensional squared shape carbon nanosheets and also between the closely cross-linked carbon sheets. The electrochemical measurements reveal that the HPCRs materials as electrodes for supercapacitor deliver a high specific capacitance of 274 F g−1 at 0.5 A g−1 with an enhanced rate capability in basic media. Moreover, a considerable energy density of 6.77 W h kg−1 at power density of 100 W kg−1 are exhibited for solid-state symmetric supercapacitor. The assembled symmetric supercapacitor also works well under 0 and −20 °C with a remarkable temperature endurance. The large-scale production of unique hierarchical porous carbon nanorods with high efficiency, low cost and one-step synthesis method will be effective electrode materials in energy storage applications.

Y2O3-MgO nanocomposite powder was synthesized by a microwave technique and doped into gas-pressure sintered BN/Si3N4 composites to acquire a highly wave-transparent material that could be utilized in spacecrafts. The XRD and SEM analyses indicated that the main phases were rod-like β-Si3N4 particles and MgSiO3. In this case, a BN/Si3N4 ceramic with 8 wt% Y2O3-MgO nanopowder displayed a density of 2.5 g/cm3. The permittivity and transmission efficiency were approximately 4.6% and 71.4%, respectively, at frequencies of 8.2–12.4 GHz, which achieved the best overall wave-transparent performance. The porosity of the material in combination with the inclusion of the boron nitride component creates a synergistic effect that appears to contribute to wave-transparent efficiency.

As new two-dimensional materials, antimony selenide (Sb2Se3) and graphene oxide (GO) are ideal photoelectric materials due to their appropriate band gap structure and strong light-matter interaction, which can be used in optical modulators, broadband ultrafast optical switches, and other photoelectric fields. The GO and Sb2Se3/GO measurements show excellent nonlinear characteristics with the modulation depth of 3.18% and 4.78%, respectively. This work proposes a harmonic dual-wavelength (HDW) fiber laser based on GO. This provides new possibilities for the research of ultrashort pulse sources with both high repetition frequency and multiple wavelengths. Furthermore, the conventional soliton mode-locking with 984 fs pulse width and soliton bundles mode-locking is obtained. The Sb2Se3/GO SA is coupled into the laser cavity for the first time to achieve higher performance mode-locked pulse. The results show that Sb2Se3/GO SA can shorten the pulse width and increase the output power more effectively than GO, such as the pulse width is shortened from 984 fs to 511 fs and the slope efficiency increased from 11.9% to 16.18%, which confirms its potential application in nonlinear optical material and ultrafast pulse generation. The results provide a new opportunity to apply traditional broadband nonlinear optical materials in ultrafast photonics and make a fundamental contribution to the development of advanced nanophotonic devices.

The surface topography of biomaterials is known to influence cellular response such as adhesion, spreading and differentiation. In this work, the behavior of osteoblasts and endothelial cells on nano-structured Zr and micro/nano-structured ZrO2 alloyed layers of Ti-6Al-4V (TC4) was investigated. Zr alloyed layer (Zr@TC4) decreases the hydrophilicity whereas ZrO2 alloyed layers (ZrO2@TC4) is more hydrophilic than TC4 and more proteins adsorb on ZrO2@TC4 followed by Zr@TC4. The cells proliferate steadily on the smooth TC4 and nano-structured Zr@TC4 surfaces and the osteoblast activity is more pronounced on Zr@TC4 than TC4. The micro/nano-structured surface on ZrO2@TC4 restricts cellular adhesion and spreading independent of the surface wettability and protein adsorption. The findings provide insights into the design of micro/nano-structured biomaterials and interfaces with controlled tissue response.

Yttrium-doped BaCeO3 is one of the most promising electrolyte candidates for solid oxide fuel cells because of its high ionic conductivity. Nd and Y co-doped BaCeO3 strategy is adopted for the further optimization of Y-doped BaCeO3 electrolyte properties. X-ray diffraction results indicate that the structure of BaCe0.8Y0.2-xNdxO3-δ (x = 0, 0.05, 0.1, 0.15) with orthorhombic perovskite phase becomes more symmetric with increasing Nd concentration. The scanning electron microscope observation demonstrates that the densification and grain size of the sintered pellets significantly enhance with the increase of Nd doping level. Whether in dry and humid hydrogen or air, the increase of Nd dopant firstly increases the conductivities of BaCe0.8Y0.2-xNdxO3-δ (x = 0, 0.05, 0.1, 0.15) and then decrease them after reaching the peak value at x = 0.05. Electrochemical impedance spectra at 350 °C can distinguish clearly the contribution of grain and grain boundary to total conductivity and the highest conductivity of BaCe0.8Y0.15Nd0.05O3-δ ascribes to the decrease in bulk and grain boundary resistances due to the synergistic effect of Nd and Y doping. The anode-supported single cell with BaCe0.8Y0.15Nd0.05O3-δ electrolyte shows an encouraging peak power density of 660 mW cm−2 at 700 °C, suggesting that BaCe0.8Y0.15Nd0.05O3-δ is a potential electrolyte material for the highly-efficient proton-conducting solid oxide fuel cell.

Copper (Cu) has garnered increasing interest due to its excellent antimicrobial activity and important roles in human metabolism. Although the biological effects of Cu have been studied, the effects of Cu nanoparticles (NPs) on cell behavior are not well understood. In this study, porous TiO2 coatings doped with different amounts of Cu NPs (designated as 0 Cu, 0.3 Cu, and 3.0 Cu) are deposited on titanium by micro-arc oxidation (MAO). The Cu NPs coated samples exhibit excellent antibacterial activity against Staphylococcus aureus (S. aureus). In vitro cytocompatibility evaluation discloses that 0 Cu and 0.3 Cu have no toxicity to osteoblasts but 3.0 Cu shows cytotoxicity. 0.3 Cu promotes proliferation and adhesion of osteoblasts and enhances extracellular matrix mineralization (ECM), but has little effects on the alkaline phosphatase activity (ALP) and collagen secretion. Surprisingly, the Cu NPs coated samples show a different behavior with endothelial cells. Both 0.3 Cu and 3.0 Cu show no cytotoxicity on endothelial cells and promote cell proliferation. Production of nitric oxide (NO) and secretion of vascular endothelial growth factor (VEGF) by the endothelial cells are observed from the Cu NPs doped TiO2 coatings.

Nitrogen removal, sludge activity and bacterial community were examined at different ciprofloxacin and ibuprofen concentrations in a sequencing batch reactor. Ammonia nitrogen (NH 4 + -N) and chemical oxygen demand (COD) elimination rates decreased as the ciprofloxacin (belonged to antibiotics) and/or ibuprofen (belonged to nonsteroidal anti-inflammatory drugs) addition. Ciprofloxacin and ibuprofen had antagonistic inhibitions on the specific rates of nitrate reduction, nitrite oxidation and ammonium oxidation. The levels of protein and polysaccharide and the protein/polysaccharide ratio in extracellular polymeric substances rose as the increment of ibuprofen, ciprofloxacin and mixed ibuprofen/ciprofloxacin concentrations. Mixed ibuprofen/ciprofloxacin did not change the role of protein in extracellular polymeric substances in the bacterial defense to ibuprofen or ciprofloxacin, and tryptophan-like protein was the main protective response of bacteria to ibuprofen, ciprofloxacin and mixed ibuprofen/ciprofloxacin compared with aromatic protein. Both of nitrifiers and denitrifiers relative abundances were lower at the mixed ibuprofen/ciprofloxacin than at the alone ibuprofen stress, while were higher than at the single ciprofloxacin pressure.

Combined impacts of diclofenac (DCF) and divalent copper (Cu2+) on the nitrogen removal, enzyme activity and bacterial community from a sequencing batch reactor were examined. DCF and/or Cu2+ in the influent rendered the decrease of ammonia nitrogen and chemical oxygen demand elimination rates. The combined inhibition impacts of Cu2+ and DCF on ammonia monooxygenase (AMO), nitrite oxidoreductase (NOR), nitrite reductase (NIR) and nitrate reductase (NAR) contents exhibited synergetic, and the AMO and NOR activities reduced levels were lower than NAR and NIR as the mixed Cu2+ and DCF concentration increment. The decreased degrees of AMO activities were higher than NOR at different mixed Cu2+ and DCF concentrations. The contents of reactive oxygen species and lactate dehydrogenase at the mixed Cu2+ and DCF stress were higher than those at the alone Cu2+ and DCF stress, and they increased as the mixed Cu2+ and DCF concentration increase. In extracellular polymeric substances (EPS), the content of protein (PN) was more easily affected by Cu2+ and mixed Cu2+/DCF than polysaccharide (PS), while PN and PS were both sensitive to the stress of DCF. Compared to seeding sludge, the denitrifying bacteria and nitrifying bacteria relative abundance ratio was decreased at the stress of alone Cu2+ and DCF, while the ratio was increased as the mixed Cu2+ and DCF concentration increment.

Understanding the contributions of soil water evaporation (E) and crop transpiration (T) to evapotranspiration (ET) is essential for irrigation management and improving crop water use efficiency. Current methods for partitioning ET are subject to uncertainties, due in part to the scale differences in determining E, T, and ET. In this study, ET of a lysimeter planted with maize (Zea mays L.) was partitioned into E and T using sensors that had compatible measurement scales: E was measured with heat pulse sensors (following the sensible heat balance (SHB) and modified sensible heat balance (MSHB) approaches), and T was measured with sap flow gauges (following the heat-balance sap-flow (HBSF) method). The accuracy of the measurements was evaluated by comparing the sum of E and T values (E + T) to weighing lysimeter ET data. During the study period, E, T, and ET had average values of 0.9, 4.0, and 4.8 mm d−1, respectively, and the fractions of E and T were 19% and 81% of E + T, respectively. In general, the E + T values agreed well with the lysimeter ET data, but slight overestimations and underestimations were observed at relatively small and relatively large ET rates, respectively. By combining the SHB and MSHB approaches and the HBSF method, it is possible to partition ET into E and T with satisfactory accuracy.

Biomedical titanium (Ti) implants with good anti-infective, osteogenic, and angiogenic properties are in great demand. SrTiO3 nanotubes (NTs) are embedded with silver oxide (Ag2O) nanoparticles (NPs) (denoted as NT-Sr-Ag) by a hydrothermal treatment of TiO2 NTs containing Ag2O NPs (denoted as NT-Ag) in a Sr(OH)2 solution. The morphology, composition, microstructure, ion release phenomenon, as well as antibacterial, osteogenic, and angiogenic activities are investigated in details. During the hydrothermal treatment, the amorphous TiO2 in the NTs morphs into cubic SrTiO3 gradually and the ordered nanotubular architecture is preserved. Some Ag2O NPs are incorporated into the structure although some of them dissolve in the solution. Long-term bacterial resistance against Staphylococcus aureus is observed as a result of the prolonged and controllable Ag+ release. NT-Sr-Ag can also release Sr2+ similarly to stimulate osteoblasts to secrete the vascular endothelial growth factor (VEGF). Both the released Sr2+ and secreted VEGF upregulate the alkaline phosphatase (ALP) activity and extracellular matrix mineralization of osteoblasts. Furthermore, better angiogenic activity is observed when endothelial cells are cultured in NT-Sr-Ag conditioned media when compared with that in NT-Ag conditioned media, which is believed to be ascribed to the positive regulation of VEGF secretion of Sr2+. NT-2Sr-Ag and NT-3Sr-Ag (Hydrothermal treatment for 2 and 3h, respectively) exhibit excellent antibacterial, osteogenic, and angiogenic activities and are promising in biomedical implants.

Aeromonas hydrophila (A. hydrophila) is a gram-negative opportunistic pathogen widely distributed in the aquatic environment, which can infect humans, birds, amphibians, reptiles, and fishes. However, the interaction between A. hydrophila and host cells has not been well characterized. In the present study, we investigated the role of autophagy in grass carp (Ctenopharyngodon idella) monocytes/macrophages following infection with A. hydrophila. Our results found that A. hydrophila challenge significantly induced autophagy, as shown by the increase of microtubule-associated protein 1 light chain 3 Ⅱ (LC3 Ⅱ) proteins and LC3 puncta in the cells. Moreover, by using confocal microscopy, the A. hydrophila-elicited autophagy was further confirmed by the colocalization of the A. hydrophila with LC3-positive autophagosome in the cells. In return, the effect of the activated autophagy on the survival of A. hydrophila was examined in the same cell model, showing that rapamycin-induced autophagy was effective in restricting the survival of A. hydrophila. In contrast, autophagy blocked by 3-methyladenine (3-MA) enhanced the amount of A. hydrophila in the cells. All these findings for the first time revealed the role of autophagy in the process of A. hydrophila invading fish immune cells.

High current anodization (HCA) is a novel strategy to fabricate micro/nano-textured surface with TiO 2 mesoporous arrays (MNT-TMAs) on biomedical titanium (Ti) and its alloys. However, our previous study shows that the structure prepared in AgNO 3 electrolyte has severe cytotoxicity because of the incorporation of Ag into the surface. The present work tries to prepare MNT-TMAs on Ti surfaces in Cu(NO 3 ) 2 electrolyte to eliminate the side effect of Ag. Our results show that the unique structure can be generated in a wide range of Cu(NO 3 ) 2 concentrations (1.0 to 12.0 g/l). The increase of Cu(NO 3 ) 2 concentration has little influence on its micromorphology but decreases the diameter of mesopores. Good interfacial strength is observed. The resultant surface possesses good cytocompatibility because of the absence of toxic Cu in the coatings. Addition of Na 3 PO 4 into the electrolyte has little influence on its microstructure, but can further improve the cytocompatibility due to the incorporation of P into the surface. Good cytocompatibility and interfacial strength render the technique promising in surface modification of implant materials.

Well-ordered, one-dimensional silver-doped anatase TiO2 nanowire (AgNW) arrays have been prepared through a hydrothermal growth process on the sputtering-deposited AgTi layers. Electron microscope analyses reveal that the as-synthesized AgNW arrays exhibit a single crystalline phase with highly uniform morphologies, diameters ranging from 85 to 95 nm, and lengths of about 11 μm. Silver is found to be doped into TiO2 nanowire evenly and mainly exists in the zerovalent state. The AgNW arrays show excellent efficient antibacterial activity against Escherichia coli (E. coli), and all of the bacteria can be killed within 1 h. Additionally, the AgNW arrays can still kill E. coli after immersion for 60 days, suggesting the long-term antibacterial property. The technique reported here is environmental friendly for formation of silver-containing nanostructure without using any toxic organic solvents.

The characteristics of high frequency and high speed are demonstrated in vertical structure organic thin film transistors (VOTFTs) fabricated by DC magnetron sputtering and vacuum evaporation. The saturated current–voltage characteristics can be determined by drain-source negative bias voltage. Responsive frequency of the device is as high as 20 kHz when rectangular wave dynamic signal is applied to the gate-source electrode, and switch characteristic time reaches the microsecond. The unsaturated current–voltage characteristics are observed when the drain-source bias voltage is positive. In the condition of V DS = 3 V and V GS = 0 V, the drain-source current I DS is 2.986 × 10 −5 A, and the current density is 1.194 mA/cm 2 . Cut-off frequency f c is 25 kHz when a small sine wave dynamic signal is applied to the gate-source electrode. The volt-ampere characteristic of VOTFTs transfers from linear to nonlinear with increasing of drain-source bias voltage.

Bacterial infection and loosing are serious complications for biomedical implants in the orthopedic, dental, and other biomedical fields and the ideal implants should combine good antibacterial ability and bioactivity. In this study, nanostructured titanium–silver (Ti–Ag) coatings with different Ag contents (1.2 to 21.6 at%) are prepared on Ti substrates by magnetron sputtering. As the Ag concentration is increased, the coatings change from having dense columnar crystals to sparse ones and eventually no columnar structure. The Ti–Ag coatings can effectively kill Staphylococcus aureus during the first few days and remain moderately antibacterial after immersion for 75 days. Compared to pure Ti, the Ti–Ag coatings show good cytocompatibility as indicated by good osteoblast adhesion, proliferation, intracellular total protein synthesis, and alkaline phosphatase (ALP) activity. In addition, cell spreading, collagen secretion, and extracellular matrix mineralization are promoted on the coatings with the proper Ag contents due to the nanostructured morphological features. Our results indicate that favorable antibacterial activity and osseointegration ability can be simultaneously achieved by regulating the Ag contents in Ti–Ag coatings.

In this study, we provide a photocurable chitosan bioink (CHI-MA), which can be used for the digital light processing (DLP) technology. The CHI-MA precursors were facilely synthesized by grafting chitosan molecular chains with methacryloyl groups. We investigated the effect of parameters, including the concentration and substitution degree (DS) of CHI-MA, on the rheology and the photocuring of bioinks and the mechanical property of photo-crosslinked gels. Using the CHI-MA with a high DS (33.6 %), the curing time to print a 150 μm thick hydrogel layer can be controlled within a reasonable short time period. Additionally, the cytotoxicity test shows that both the photocuring process and the photo-crosslinked hydrogels exhibit an excellent biocompatibility. Through the DLP printing, the CHI-MA bioink can be processed into complex 3D hydrogel structures with high-resolution, high-fidelity and good biocompatibility. It indicates that the photocurable CHI-MA would be a good bioink suitable for the DLP printing.

The geometric structures, hydrogen bond types, IR spectra and nonlinear optical properties of chitosan oligosaccharide (degree of polymerization 2–5) are studied by density-functional theory (DFT) at B3LYP/6-31+G(d) level. We have analyzed the statistics of relationship between IR spectra and bond lengths, and angles of amino, hydroxyl. The results show that: (1) the active groups C 3 –OH, C 6 –OH and –NH 2 can form intramolecular hydrogen bond in chitosan oligosaccharide; (2) the IR spectra of three active groups have size effect in growth process, however, its IR intensity increases significantly and IR frequencies are red shifted obviously when the active hydroxyl form hydrogen bonds, because the bond length of active hydroxyl becomes longer; (3) the effect of hydrogen bond on intensity and frequency of the three vibration mode of amino is the main factor and complication. The paper also provides the nonlinear optical properties of chitosan oligosaccharide. The reason why hydrogen bond can make an appreciable difference to IR spectra, and the nonlinear optical properties of chitosan oligosaccharide are discussed. This research has important significance in the characterization of chitosan oligosaccharide, the properties of chitosan material and hydrogen bond by infrared spectroscopy.

Lipase produced by Penicillium expansum is widely used in laundry detergent and leather industry; however, the absence of an efficient transformation technology sets a major obstacle for further enhancement of its lipase productivity through advanced gene engineering. In this work, Agrobacterium tumefaciens-mediated transformation (ATMT) was investigated for P. expansum PE-12 transformation, using hygromycin phosphotransferase (hph) as a selectable marker gene. As a result, we revealed that the frequency of transformation surpassed 100 transformants/10(5)condida, most of the integrated T-DNA appeared as a single copy at a random position in chromosomal DNA, and all the transformants showed mitotic stability. Facilitated by this newly established method, for the first time, P. expansum PE-12 was genetically engineered to improve the lipase yield, through a homologous expression vector carrying the endogenous lipase gene (PEL) driven by the strong constitutive promoter of the glyceraldehydes-3-phosphate dehydrogenase gene (gpdA) from Aspergillus nidulans. The highest expression level of the engineered strain reached up to 1700 U/mL, nearly 2-fold of the original industrial strain (900 U/mL). Our reproducible ATMT system has not only revealed the great potential of homologous expression-directed genetic engineering, which is more efficient and specific compared to traditional mutagenesis, but also provided new possibilities and perspectives for any other practical applications of P. expansum-related genetic engineering in the future.

In this paper, firstly, a new mapping method is used to obtain the variable separation solutions, with two arbitrary functions, of the (2+1)-dimensional Boiti–Leon–Pempinelli equation. From the variable separation solution and by selecting appropriate functions, some novel Jacobian elliptic wave structure and periodic wave evolutional behaviors are investigated.