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Catalase is an effective biocatalyst to degrade hydrogen peroxide to water and oxygen that can serve in textile effluent treatment to remove residual H2O2. Thermostable catalases are needed to withstand both the high temperature and pH of textile wastewater. We have cloned the Mn-containing catalase gene ACS24898.1 from Geobacillus sp. WCH70, which originated from thermophilic organisms, and expressed it in Escherichia coli in activated form. The recombinant protein has been purified to homogeneity and identified to be a new homo-hexamer Mn-containing catalase. The native molecular mass of the catalase has been measured to be 138 kDa by size-exclusion chromatography. The new enzyme has optimum catalyzed activity at pH 9.0 and a temperature of 75 °C. It is thermostable up to 70 °C for 8 h incubation and maintains 80% and 50% activity, respectively, at 80 °C after 5 h and 90 °C after 1 h. At 75 °C and pH 9.0, the Km is 67.26 mM for substrate H2O2 and the rate of reaction at H2O2 saturation, Vmax, is 75,300 U/mg. The thermophilic and alkaline preferred properties of this new Mn-catalase are valuable features in textile wastewater treatment.

Chemical constituents of naturally decayed Qinghai spruce branches were analyzed in terms of holocellulose, lignin, and pentosan. The holocellulose content declined from 57.98% to 35.29% in one year. The rate of change may be related to weather conditions, i.e., the rate of variation was higher when the temperature was high and rainfall was abundant. The changes in lignin and pentosan relative content were completely different from holocellulose; they increased first and then decreased during the decay period. Compared with fresh raw materials, pentosan content (from 14.44% to 25.9%) was increased by 79.4% after four months decay. The highest yield of furfural (10.2%) prepared by a two-stage method from decayed Qinghai spruce branches was similar to the reported yield from corncobs.

This paper presents free and forced vibration analysis of airtight cylindrical vessels consisting of elliptical, paraboloidal, and cylindrical shells by using Jacobi-Ritz Method. In this research, the theoretical model for vibration analysis is formulated by Flügge’s thin shell theory and the solution is obtained by Rayleigh-Ritz method. The vessel structure is divided into shell components (i.e., ellipsoid, parabolic, and cylinder) and their segments, and each displacement field of shell segments is represented by the Jacobi polynomials and the standard Fourier series. The continuous conditions at the interface are modeled by using the spring stiffness technique. The reliability and the accuracy of the present method are verified by comparing the results of the proposed method with the results of the previous literature and the finite element method (FEM). Moreover, some numerical results for free and forced vibration of elliptical-cylindrical-elliptical vessel (ECE vessel) and paraboloidal-cylindrical-elliptical vessel (PCE vessel) are reported.

The free vibration analysis of moderately thick functionally graded (FG) sector plates resting on two-parameter elastic foundation with general boundary conditions is presented via Fourier-Ritz method, which is composed of the modified Fourier series approach and the Ritz procedure. The material properties are assumed to vary continuously along the thickness according to the power-law distribution. The bilayered and single-layered functionally graded sector plates are obtained as the special cases of sandwich plates. The first-order shear deformation theory (FSDT) is adopted to construct the theoretical model. Under current framework, regardless of boundary conditions, each displacement and each rotation of plates is represented by the modified Fourier series consisting of a standard Fourier cosine series and several closed-form auxiliary functions introduced to ensure and accelerate the convergence of the series representation. Then, the accurate solutions are obtained by using the Ritz procedure based on the energy function of sector plates. The present method shows good convergence, reliability, and accuracy by comprehensive investigation with some selected classical boundary conditions. Numerous new vibration results for moderately thick FG sandwich sector plates are provided. The effects of the elastic restraint parameters and so forth on free vibration characteristic of sector plates are presented.

The aim of this paper is to extend the modified Fourier-Ritz approach to evaluate the free vibration of four-parameter functionally graded moderately thick cylindrical, conical, spherical panels and shells of revolution with general boundary conditions. The first-order shear deformation theory is employed to formulate the theoretical model. In the modified Fourier-Ritz approach, the admissible functions of the structure elements are expanded into the improved Fourier series which consist of two-dimensional (2D) Fourier cosine series and auxiliary functions to eliminate all the relevant discontinuities of the displacements and their derivatives at the edges regardless of boundary conditions and then solve the natural frequencies by means of the Ritz method. As one merit of this paper, the functionally graded cylindrical, conical, spherical shells are, respectively, regarded as a special functionally graded cylindrical, conical, spherical panels, and the coupling spring technology is introduced to ensure the kinematic and physical compatibility at the common meridian. The excellent accuracy and reliability of the unified computational model are compared with the results found in the literatures.

The brown planthopper (BPH, Nilaparvata lugens) is a destructive, monophagous, piercing-sucking insect pest of rice. Previous studies indicated that jasmonic acid (JA) positively regulates rice defense against chewing insect pests but negatively regulates it against the piercing-sucking insect of BPH. We here demonstrated that overexpression of allene oxide cyclase (AOC) but not OPR3 (cis-12-oxo-phytodienoic acid (OPDA) reductase 3, an enzyme adjacent to AOC in the JA synthetic pathway) significantly increased rice resistance to BPH, mainly by reducing the feeding activity and survival rate. Further analysis revealed that plant response to BPH under AOC overexpression was independent of the JA pathway and that significantly higher OPDA levels stimulated rice resistance to BPH. Microarray analysis identified multiple candidate resistance-related genes under AOC overexpression. OPDA treatment stimulated the resistance of radish seedlings to green peach aphid Myzus persicae, another piercing-sucking insect. These results imply that rice resistance to chewing insects and to sucking insects can be enhanced simultaneously through AOC-mediated increases of JA and OPDA and provide direct evidence of the potential application of OPDA in stimulating plant defense responses to piercing-sucking insect pests in agriculture.

The location and structure of the framework Ti4+ species in Ti-MWW zeolites were studied by density functional theory (DFT) based on the cluster models mimicking the Ti-MWW zeolite with a Si/Ti ratio of 35. The geometry, spectroscopic properties and energies of substitution for the Ti4+ species at different T sites were investigated. The results indicated that the Ti4+ species in form of Ti(OSi)4 prefers to locate at the T1 and T3 sites, positioning on the edge of 12-membered ring cavity and the intersection of the 10-membered ring intralayer channels in MWW, respectively. In their calculated infrared (IR) spectra, the vibrational mode at 960 cm−1 band is actually a collective vibration of the antisymmetric stretching of Ti(–O–Si)4 in a deformed tetrahedral geometry. The totally symmetric Ti(OSi)4 tetrahedron at the Ti4 site is absent from the 960 cm−1 band because the vibrational mode is infrared inactive. Hydrolysis of a Ti–O–Si bridge was thermodynamically favorable and resulted in a tripodal defect Ti species with an inversed Ti–OH group and a remaining Si–OH in the adjacent T site. The calculated IR spectra of the tripodal Ti species have a blue shift in the characteristic IR band to 990–1000 cm−1. The UV–vis spectra of the Ti4+ species were calculated by the time-dependent DFT method. The calculated IR and UV–vis spectra are in very good agreement with the experimental measurements, and provide microscopic features for the identification of the structure of framework titanium in Ti-MWW zeolites.

The spatter generation of dry hyperbaric gas metal arc welding (GMAW) was investigated by using a high-speed digital camera system. Two spatter types, droplet deviated spatter and droplet rebounded spatter, were observed. The generation of droplet deviated spatter is similar to the spatter generation in globular repelled transfer of GMAW at normal pressure, which is due to the high horizontal speed of the droplet detachment. This spatter type begins to appear at ambient pressure reached 0.2 MPa. Another type, droplet rebounded spatter, is a new spatter generating process. The spatter is always generated after the cathode root burning on the droplet which contacts to the workpiece. And then, the droplet rebounds to the free space and changes into the spatter instead of adhering to the workpiece. Droplet rebounded spatter is generated at the ambient pressure over 0.4 MPa. The reason that the electromagnetic force is the driving force of droplet rebounded was analyzed.

The evolution of microstructure and coefficient of thermal expansion (CTE) of the Al–50Si (wt.%) alloy manufactured by spray deposition followed by hot isostatic pressing (HIP) are systematically investigated. The results indicate that the microstructure of the deposited alloy is composed of primary Si with average size of 12.5 ± 0.1 μm and α-Al. The CTE of the deposited alloy is higher than the corresponding alloy produced by casting due to the high solid solubility of Al in Si. After HIP, the CTE is lower than the parent as-deposited alloy owing to the high solid solubility of Si in Al. The residual thermal stress results in a higher CTE during the second heating as a result of the CTE mismatch between the Al matrix and the primary Si particles. Furthermore, the measured CTE value is in good agreement with the Turner model after complete densification by HIP at 843 K.

This paper analyzed the free vibration of functionally graded (FG) doubly-curved shells with un-uniform thickness distribution based on Ritz method. The energy method and first-order shear deformation theory are adopted to derive the formulas. In this paper, the stepped FG doubly-curved shells are divided into their segments in axial direction according to the steps of the structures, and the displacement functions of shell segments are consisted with Jacobi polynomials along axial direction and standard Fourier series along circumferential direction. In addition, the boundary conditions at ends of the stepped FG doubly-curved shells and the continuity conditions at two adjacent segments were enforced by penalty method. Then the final solutions can be obtained based on Ritz method. Finally, to confirm the validity of proposed method, the results with the same conditions are compared by Finite Element Method (FEM) and experiment. The results show that the proposed method has the advantage of fast convergence, high accuracy and simple boundary simulation etc.

In port surveillance, monitoring based on satellite video is a valuable supplement to a ground monitoring system because of its wide monitoring range. Therefore, automatic ship detection and tracking based on satellite video is an important research field. However, because of the small size of ships without texture and the interference of sea noise, it is also a challenging subject. An approach of automatic detection and tracking moving ships of different sizes using satellite video is presented. First, motion compensation between two frames is realized. Then, saliency maps of multiscale differential image are combined to create dynamic multiscale saliency map (DMSM), which is more suitable for the detection of ships of different sizes. Third, candidate motion regions are segmented from DMSM, and moving ships can be detected after the false alarms are removed based on the surrounding contrast. Fourth, important elements such as centroid distance, area ratio, and histogram distance from moving ships are used to perform ship matching. Finally, ship association and tracking are realized by using the intermediate frame in every three adjacent frames. Experimental results on satellite sequences indicate that our method can effectively detect and track ships and obtain the target track, which is superior in terms of the defined recall and precision compared with other classical target tracking methods.

Organic phase change materials (PCM) have been regarded as one of the most promising candidates for the application of energy storage and temperature control due to their advantages in latent heat. However, their intrinsically low thermal conductivity (λ) is the Achilles heel, and the most common solution is to utilize thermal conductive reinforcements to fabricate composite PCMs. The research focus remains how to promote the efficiency of thermal conductive reinforcements. Here, a CNT-Cu foam hybrid reinforcement was fabricated through a high temperature tube furnace process. Different from conventional carbon film coated metal foam, CNTs with the length comparable to the pore size were radially grown on the surface of Cu foam with Ni catalysts, which can not only reduce the low-λ regions inside the foam skeleton, but also connect every branches of the foam to improve the integrity of the whole reinforcement, and the thermal conductivity of the composite was promoted to 3.49 W·m−1·K−1 from 0.105 W·m−1·K−1 of paraffin. Moreover, this reinforcement exhibited abilities to compensate the loss of latent heat and suppress the supercooling of the composite, indicating their great prospects in the application of phase change energy storage and temperature control. Keywords: Carbon nanotube, Cu foam, Phase change materials, Thermal conductivity

The paper introduces a semi-analytical approach to analyze free vibration characteristics of stepped functionally graded (FG) paraboloidal shell with general edge conditions. The analytical model is established based on multi-segment partitioning strategy and first-order shear deformation theory. The displacement components along axial direction are represented by Jacobi polynomials, and the Fourier series are utilized to express displacement components in circumferential direction. Based on penalty method about spring stiffness technique, the general edge conditions of doubly curved paraboloidal shell can be easily simulated. The solutions about doubly curved paraboloidal shell were solved by approach of Rayleigh&ndash, Ritz. Convergence study about boundary parameters, Jacobi parameters et al. are carried out, respectively. The comparison with published literatures, FEM and experiment results show that the present method has good convergence ability and excellent accuracy.

phytic acid is the major form of p in crop seeds. To reveal the correlations between phytic acid concentration (pAC) in soybean [Glycine max (L.) Merr.] seed and ecophysiological factors, the soybean cultivar Yudou25 was planted at five locations of Henan, China, on 13 different sowing dates in 2009 and 2010. results showed that six ecophysiological factors were highly correlated with pAC, including four soil nutrition factors (available K [AK], available p [Ap], hydrolyzable N [HN], and S in soil) and two meteorological factors (diurnal temperature range at blooming and podding [DTrBp] and mean temperature at seed filling and maturity [MTFM]) from high to low in the contribution to the pAC difference. phytic acid concentration was negatively correlated with AK and HN but positively correlated with Ap and available S, DTrBp, and MTFM. These results have potentially wide applications for the production of lower pAC soybean seeds. H. Li, Z. Wen, J. Li, H. Zhang, Y. Wu, C. Lei, S. Wang, J. Wang, W. Li, and W. Lu, Institute of Industrial Crops/Zhengzhou National Subcenter for Soybean Improvement/Key Laboratory of Oil Crops in Huanghuaihai Plains, Ministry of Agriculture, P R China, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China; X. Wang, Dep. of Life Science, Zhoukou Normal Univ., Zhoukou 466000, China; Y. Ma, Research Center of Agricultural Quality Standards and Testing Techniques, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China; Z. Geng, Zhoukou Agricultural Institute, Zhoukou 466001, China; C. Yang, Puyang Agricultural Institute, Puyang 457000, China. This work was supported by the China Agriculture Research System (nycytx-004), Zhengzhou leading scientists training program (096SYJH14103), functional quality of new varieties of genetically modified soybean cultivation (2011ZX08004-003), and national science and technology support program (2011BAD35B06). Received 2 Feb. 2012. *Corresponding author (123bean@163.com). Abbreviations: AK, available K; AP, available P; DTRBP, diurnal temperature range at blooming and podding; HN, hydrolyzable N; MTFM, mean temperature at seed filling and maturity; PA, phytic acid; PAC, phytic acid concentration. Published in Crop Sci. 53:2195–2201 (2013). doi: 10.2135/cropsci2012.02.0068 © Crop Science Society of America | 5585 Guilford Rd., Madison, WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher.

Composting is widely used for animal waste disposal, and bamboo charcoal (BC) can be used for nitrogen conservation during composting. However, the effects of BC on antibiotic resistance genes (ARGs) during chicken manure composting are still unclear. This study investigated the effects on ARGs of adding different proportions of BC (0%, 5%, 10%, and 20% w/w) to chicken manure compost. After 26 days, the relative abundances (RAs) of most ARGs (tetC, tetG, tetW, tetX, sul2, drfA1, drfA7, ermB, ermF, ermQ, and ermX) and intI1 declined by 21.6–99.5%, whereas sul1 increased by 7.5–17.7 times. The average RAs reductions with 0%, 5%, 10%, and 20% BC were 0.85, 1.05, 1.08, and 1.15 logs, respectively. The most important environmental factor for the ARG profiles was temperature according to redundancy analysis. Furthermore, BC significantly decreased the bio-Cu and bio-Zn levels, thereby reducing the co-selection pressure from heavy metals. Different proportions of BC had no significant effects on the removal of tetG, tetW, tetX, sul2, drfA1, and ermB. Supplementation with 10% BC was more effective at removing tetC and drfA7 compared with the other treatments. The results suggested that 10% BC supplementation is appropriate for reducing ARGs in chicken manure compost.

In this study, swine manure containing sulfachloropyridazine sodium (SCPS) and zinc was subjected to mesophilic (37°C) anaerobic digestion (AD). The absolute abundances (AAs) of antibiotic resistance genes (ARGs) were evaluated, as well as intI1 and intI2, and the degradation of SCPS according to variation in the amount of bio-available zinc (bio-Zn). In digester that only contained SCPS, the concentrations of SCPS were lower than that digesters both contain SCPS and Zn. Compared with the control digester, the addition of SCPS increased the AAs of sul1, sul3, drfA1, and drfA7 by 1.3-13.1 times. However, compared with the digester with SCPS but no added Zn, the AAs of sul3, drfA1, and drfA7 were decreased by 21.4-70.3% in the presence of SCPS and Zn, whereas sul1 and sul2 increased 1.3-10.7 times. There were significant positive correlations (P

This study explored the effects of composting using three temperature regimes, namely, insufficient thermophilic composting (ITC), normal thermophilic composting (NTC), and continuous thermophilic composting (CTC), on antibiotic resistance genes (ARGs), integrons, and human pathogenic bacteria (HPB), as well as the mechanisms involved. The NTC and CTC treatments led to greater decreases in 5/10 ARGs and two integrons than ITC, and the abundances of ARGs (tetC, tetG, and tetQ) and int1 only declined in the NTC and CTC treatments. The abundances of HPB decreased by 82.8%, 76.9%, and 96.9% under ITC, NTC, CTC, respectively. Redundancy analysis showed that both bacterial succession and horizontal gene transfer play important roles in the variation of ARGs, and the changes in different ARGs were due to diverse mechanisms. CTC performed significantly better at reducing ARGs, integrons, and HPB, thus it may be used to manage the public health risks of ARGs in animal manure.

Moving ship detection is an important issue with the development of video satellite. However, it is difficult for the registration of sea scenes imaging with motion camera. In this paper, we propose a new method to detect moving ship by combining optical flow and video attention saliency for video satellite with image registration. Video visual attention is a consequence of some saliency features such as optical flow, Gabor features, intensity. The model proposed for ship detection mainly includes three stages. Firstly, the moving region is estimated based on optical flow with corners. Secondly, Gabor filter is used for texture features extraction of video images. Finally, the above saliency features as several channels are integrated to a quaternion, which can indicate where the ships are located. The experimental results show that the proposed model can effectively extract moving ships in video images without image registration.

A sulfonated activated carbon fiber catalyst (SACF) was prepared through ψ-irradiation-induced grafting of styrene onto the surface of activated carbon fiber (ACF) with an irradiation dose of 0.837 kGy/h for 48 h that was then sulfonated with chlorosulfonic acid under mild reaction conditions. Scanning electron microscopy observation showed that the ACF was wrapped by a thin layer of copolymer, and Fourier transfer infrared spectroscopy analysis indicated that sulfonic acid groups were successfully introduced onto the ACF. Pore structure analysis based on nitrogen adsorption isotherms at 77 K. demonstrated that pore parameters of ACF were well maintained after the process of grafting and sulfonation modification. Proper conditions for the SACF preparation were sulfonated at 80 °C for 1.5 h in the 20% mass percentage of chlorosulfonic acid solution using ACF precursor, whose acid density could reach 1.47 mmol/g. The sulfonated ACF was used as catalyst for the esterification of acetic acid and ethanol. Evaluation of the catalytic activity of SACF showed evident advantages over other typical catalyst, with a turnover frequency value of 0.780 min−1, about five times higher than Nation.

Zinc ferrite supported on porous carbon (ZFPC) was prepared by thermal conversion of a mixture of ferric nitrate, zinc chloride, and novolac resin and was used as a catalyst for the catalytic oxidation of mercaptan under alkali-free conditions. ZFPC exhibited a high butyl mercaptan removal efficiency (222.29 mg/g), fast catalytic degradation rate, stable catalytic activity, and outstanding regenerative ability. It is believed that the effective butyl mercaptan removal was achieved by the synergism between adsorption of porous carbon and catalysis of zinc ferrite. The mechanism of catalytic oxidation of mercaptan into disulfides by ZFPC was further discussed based on the contrast experiment. The results indicated that oxidation of mercaptan in the presence of ZFPC followed the Merox process, in which Zn(II) acted as basic sites and Fe(III) acted as oxidation sites.

Subsolidus phase relations of CaO–In 2 O 3 –B 2 O 3 system have been investigated mainly by the conventional solid-state reaction technique and powder X-ray diffraction method. There are nine definite three-phase regions under present experimental conditions. Six binary compounds and one ternary compound were found to exist in this system. Crystal structure of the ternary compound CaInBO 4 was determined from X-ray powder diffraction data using Rietveld method. It crystallizes in the orthorhombic space group Pnma (No. 62) with a = 10.3120(3) A, b = 3.42519(8) A, c = 9.5150(3) A, V = 336.07(2) A 3 and Z = 4. Mixed occupancies were confirmed in this structure, Ca and In atoms are distributed between two atom sites: 93.6%Ca and 6.4%In occupy one site, 93.6%In and 6.4%Ca occupy another. Two In(Ca)O 6 octahedra and two Ca(In)O 7 polyhedra are linked each other by sharing edges to form ribbons in the a – c plane and extend infinitely along the direction of the b axis. The infrared spectrum of CaInBO 4 has been measured, which is consistent with the crystallographic study. In general, compounds MRBO 4 (M and R are divalent and trivalent cations, respectively) are in a large family of monoborates with different structure types strictly depending on the relative size of the M and R ions.

The distribution model of temperature for the billets was established based on the porosity formation mechanism. By calculating the numerical relationship between the temperature of the deposition layer and the formation ability of the porosity, the distribution of porosity for spray formed 7075 aluminum billets was predicted and the influence of superheat on the formation probability of porosity was analyzed. The results show that a denser billet can be obtained with the average temperature of 813 K of the droplets and a liquid fraction of 50%. The porosity would increase whether the temperature further increased or decreased. Finally, the 7075 aluminum alloy was prepared by spray deposition technique with the optimum process parameters. It can be found that the distribution and types of the porosity were different at different locations. These results are in good agreement with the porosity distribution law.

This paper deals with the problem of multi-objective fault-tolerant output tracking control for the longitudinal model of a flexible air-breathing hypersonic vehicle (FAHV). There exist some challenges for control design for the vehicles due to the inherent couplings between the propulsion system, the airframe dynamics, and the presence of strong flexibility effects. This paper addresses the problem of guaranteed cost fault-tolerant output tracking control with regional pole constraints against actuator faults for the FAHV system. A non-linear longitudinal model is adopted for control design because of the complexity of the FAHV systems. First, a linearized model is established around the trim point including the state of altitude, velocity, angle of attack, pitch angle, and pitch rate, etc. for a non-linear, dynamically coupled simulation model of a FAHV with the aim to address the multi-objective fault-tolerant output tracking control problem. Second, the control objective and models of actuator faults are presented. Third, by utilizing the Lyapunov functional approach, a multi-objective analysis condition is proposed in terms of convex optimization problems, that can be easily solved via standard numerical software. Then, a multi-objective fault-tolerant controller is designed such that the resulting closed-loop system is asymptotically stable and satisfies a prescribed performance cost with the simultaneous consideration of poles assignment in spite of possible actuator failure. Finally, the simulation results are given to show the effectiveness of the proposed method, which is verified by an excellent altitude reference and velocity tracking performance.

e24224Background: Recently, micro/nanotechnology has been involved in developing highly sensitive liquid biopsy technique because of the manipulation capability at single tumor cell level. However,...

The spread of antibiotic resistance genes in river systems is an emerging environmental issue due to their potential threat to aquatic ecosystems and public health. In this study, we used droplet digital polymerase chain reaction (ddPCR) to evaluate pollution with clinically relevant antibiotic resistance genes (ARGs) at 13 monitoring sites along the main stream of the Weihe River in China. Six clinically relevant ARGs and a class I integron-integrase (intI1) gene were analyzed using ddPCR, and the bacterial community was evaluated based on the bacterial 16S rRNA V3–V4 regions using MiSeq sequencing. The results indicated Proteobacteria, Actinobacteria, Cyanobacteria, and Bacteroidetes as the dominant phyla in the water samples from the Weihe River. Higher abundances of blaTEM, strB, aadA, and intI1 genes (103 to 105 copies/mL) were detected in the surface water samples compared with the relatively low abundances of strA, mecA, and vanA genes (0–1.94 copies/mL). Eight bacterial genera were identified as possible hosts of the intI1 gene and three ARGs (strA, strB, and aadA) based on network analysis. The results suggested that the bacterial community structure and horizontal gene transfer were associated with the variations in ARGs.

A kind of ZnO/MgO core-sheath structure has been prepared directly by the pyrolysis of a mixture of polyvinyl alcohol, magnesium acetate, and zinc chloride coating on glass fiber mats at 450 °C for 60 min. The growing process and effect of the anions on the morphology of ZnO/MgO structures have been preliminarily discussed. The results indicate that ZnCl2 will transform to ZnO crystal through an intermediate of zinc hydroxide chloride. ZnO crystal act as the core of the micorod, and MgO lamellas act as the sheath. The concurrence of chloride and acetate anions in the precursor is necessary for the growth of ZnO/MgO core-sheath structures. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A novel kind of porous carbon embedding ZnO nano-particles has been prepared by pyrolysis of poly vinyl alcohol (PVA) and ZnCl 2 mixture coated on glass fiber mats. The structure of the composite was investigated through scanning electron microscopy, X-ray powder diffraction, X-ray energy spectrum analysis, N 2 adsorption at 77 K and thermogravimetry analysis. The results indicate that the pyrolysis time is the key factor that controls the morphology and size of ZnO particles growing in carbonous materials. Various nanostructures, including zinc hydroxide chloride (ZHC) lamellae-packed ellipsoid particles, hexagonal pencil-like ZnO nanorods, oriented ZnO nanorods array, and ZnO microrods sized range of 30 nm–3 μm could be prepared by controlling the pyrolysis time from 30 to 180 min. Specific surface areas of carbon supports were in range of 380–630 m 2 /g. The growth process of nano-crystal of ZnO is believed to undergo the conversion of ZnCl 2 to ZHC, and then the decomposition of ZHC to ZnO while they were heated at 450 °C.

The image phase coherences (PCs) remain invariant when brightness and contrast changes. A new method of remote sensing image registration is proposed. PCs are firstly extracted from the reference image and the input image. In order to improve the registration efficiency, in the first step the PCs are firstly down-sampled using Gaussian pyramid method, and the coarse translation parameters are calculated using phase correlation. In the second step, Harris corners are detected from the two images, and normalized cross-correlation (NCC) function based on PCs is used to find the corresponding matching corners of the two images, and then obtain parameters of an alignment transform model. Experiments have demonstrated that the coarse-to-fine method can be successfully applied to multi-source images registration.

Conductive papers were prepared via surface coating with graphite or carbon black using either carboxylated styrene butadiene latex or starch as the binder. It is of practical interest to determine the percolation threshold for the coated paper product made using a binary system consisting of conductive filler and binder. In this study, the electro-conductivity threshold of various conductive papers was determined based on experimental data according to the percolation law. Results showed that the conductivity of coated, conductive paper is a function of the volume fraction of conductive filler, which can be described well by the percolation theory. The percolation thresholds of graphite/latex, graphite/starch, carbon black/latex, and carbon black/starch coatings were 17.66, 12.36, 11.71, and 8.69 vol.%, respectively. At concentrations higher than the percolation threshold, the conductivity of conductive paper using graphite as the conductive filler was much higher than that achieved using carbon black at a similar volume fraction. The present paper has significant practical implications for conductive paper technology using graphite filler based on surface coating technology.

The silkworm Bombyx mori is an oligophagous insect that feeds mainly on mulberry leaves. The olfactory system of silkworm is a good model to study olfaction in Lepidoptera. Here, we carried out shotgun proteomic analysis and MS sequencing of the silkmoth antennae. A total of 364 proteins were detected, 77 were female specific, 143 were male specific, and 144 were expressed in both male and female antennae. Five odorant-binding proteins, two chemosensory proteins, and one olfactory receptor were identified. They may play a major role in the perception of odorants. An esterase and an aldehyde dehydrogenase were found only in male antennae. Glutathione S-transferases (GSTs) and cytochrome P450s, also found in silkworm antennae, may be involved in the degradation of xenobiotics. Additionally, antioxidation proteins and immunity proteins were identified. Juvenile hormone binding proteins (JHBP), juvenile hormone resistance protein II, and juvenile hormone episode hydrolase (JHEH) were found in the proteomic analysis, which suggests that the antennae are a target for juvenile hormone in the silkworm. Our results provide insight into the expression of proteins in the antennae of silkworm and will facilitate the future functional analysis of silkworm antennae.

Pollution resulting from the discharge of textile dyes into water systems has become a major global concern. Because peroxidases are known for their ability to decolorize and detoxify textile dyes, the peroxidase activity of Vitreoscilla hemoglobin (VHb) has recently been studied. It is found that VHb and variants of this enzyme show great promise for enzymatic decolorization of dyes and may play a role in achieving their successful removal from industrial wastewater. The level of VHb peroxidase activity correlates with two amino acid residues present within the conserved distal pocket, at positions 53 and 54. In this work, sitedirected mutagenesis of these residues was performed and resulted in improved VHb peroxidase activity. The double mutant, Q53H/P54C, shows the highest dye decolorization and removal efficiency, with 70% removal efficiency within 5 min. UV spectral studies of Q53H/P54C reveals a more compact structure and an altered porphyrin environment (λSoret = 413 nm) relative to that of wild-type VHb (λSoret = 406), and differential scanning calorimetry data indicate that the VHb variant protein structure is more stable. In addition, circular dichroism spectroscopic studies indicate that this variant's increased protein structural stability is due to an increase in helical structure, as deduced from the melting temperature, which is higher than 90°C. Therefore, the VHb variant Q53H/P54C shows promise as an excellent peroxidase, with excellent dye decolorization activity and a more stable structure than wild-type VHb under high-temperature conditions.

To investigate whether the dsRNA of a gene has species-specific, broad-spectrum, or off-target effects on lepidopteran insects, we identified a methionine-rich storage protein gene (OfSP) from Asian corn borer, Ostrinia furnacalis (Guenee) (Lepidoptera: Pyralidae), using high-throughput sequence technology. The OfSP gene possesses three functional domains (N, M, and C), which are predominantly expressed in the last instars of Asian corn borer. This gene is also a key element for insect development and reproduction. The dsRNAs for the three functional domains of the OfSP gene were synthesized and sprayed on either Asian corn borer or on cotton bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), during the first instar. The dsRNA targeting the C-terminal domain can cause high mortality rates in both insects, whereas those targeting the M- and N-terminal domains only cause high mortality in the Asian corn borer. These results can be used to develop dsRNA with species-specific or broad-spectrum bio-insecticidal properties. More importantly, after dsRNA spraying, we also found typical systemic RNAi in the phenotypes that resulted in abnormal ecdysis of the larvae and pupae. Moreover, sterile eggs were found in the next generation. To analyze the broad-spectrum link to dsRNA off-target effects, the whole transcriptome siRNA libraries for these two species were constructed. Results further confirmed that 21 nucleotide siRNAs are unlikely to produce the off-target effect if conserved genes are not selected. These findings provide direct evidence confirming that dsRNA is a biologically safe insecticide in lepidopteran insect pest control.

Evaluation of human epidermal growth factor receptor 2 in breast cancer with a novel specific aptamer