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Magnetic Barkhausen noise (MBN), sensitive to the microstructure of materials, can be applied in the surface decarburization depth detection of ferromagnetic specimens. However, the effects of core microstructures on the determination results of decarburization depth have not been explored. In this study, MBN was employed to evaluate the magnetic properties of the decarburized 60Si2Mn spring steels with martensitic and pearlitic core microstructures. Spring steel samples were austenitized at different times to generate different decarburization depths. Seven magnetic features were extracted from the MBN butterfly profiles. We used the variation coefficient, linear correlation coefficient, and normalized sensitivity to discuss the influence of the core microstructures on these seven features. The different core microstructures led to a large difference in the ability of MBN features to characterize the decarburization layer depth. However, three features of MBN butterfly profiles demonstrated an approximately linear dependency (linear correlation coefficient > 94%) on surface decarburization depth and monotonically increased with the increase in depth in both core microstructures of spring steels.

Changes in net primary productivity (NPP) to global change have been studied, yet the relative impacts of global change on grassland productivity at large scales remain poorly understood. Using 182 grassland samples established in 17 alpine meadows (AM) and 21 desert steppes (DS) in China, we show that NPP of AM was significantly higher than that of DS. NPP increased significantly with increasing leaf nitrogen content (LN) and leaf phosphorus content (LP) but decreased significantly with increasing leaf dry matter content (LDMC). Among all abiotic factors, soil nutrient factor was the dominant factor affecting the variation of NPP of AM, while the NPP of DS was mainly influenced by the changing of precipitation. All abiotic factors accounted for 62.4% of the spatial variation in the NPP of AM, which was higher than the ability to explain the spatial variation in the NPP of DS (43.5%). Leaf traits together with soil nutrients and climatic factors determined the changes of the grassland productivity, but the relative contributions varied somewhat among different grassland types. We quantified the effects of biotic and abiotic factors on grassland NPP, and provided theoretical guidance for predicting the impacts of global change on the NPP of grasslands.

Plant functional traits are a representation of plant resource utilization strategies. Plants with higher specific leaf area (SLA) and lower leaf dry matter content (LDMC) exhibit faster investment-return resource utilization strategies. However, the distribution patterns and driving factors of plant resource utilization strategies at the macroscale are rarely studied. We investigated the relative importance of climatic and soil factors in shaping plant resource utilization strategies at different life forms in forests using data collected from 926 plots across 163 forests in China. SLA and LDMC of plants at different life forms (i.e., trees, shrubs, and herbs) differ significantly. Resource utilization strategies show significant geographical differences, with vegetation in the western arid regions adopting a slower investment-return survival strategy and vegetation in warmer and wetter areas adopting a faster investment-return survival strategy. SLA decreases significantly with increased temperature and reduced rainfall, and vegetation growing in these conditions exhibits conservative resource utilization. Mean annual precipitation (MAP) is a key climatic factor that controls the resource utilization strategies of plants at the macroscale. Plants use resources more conservatively as soil pH increases. The influence of climate and soil factors is coupled to determine the resource utilization strategies of plants occupying different life forms at the macroscale, but the relative contribution of each varies across life forms. Our findings provide a theoretical framework for understanding the potential impact of increasing global temperatures on plant resource utilization.

Leaf nutrient content and its stoichiometric relationships (N/P ratio) are essential for photosynthesis and plant growth and development. Previous studies on leaf nutrient-related functional traits have mainly focused on the species level and regional scale, but fewer studies have investigated the distribution patterns of the leaf N and P contents (LN, LP) and N/P ratios (N/P) in communities and their controlling factors at a large scale; therefore, we used LN, LP, and N/P data at 69 sites from 818 forests in China. The results showed significant differences (p < 0.05) in the LN, LP, and N/P at different life forms (tree, shrub, and herb). Neither LN, LP, nor N/P ratios showed significant patterns of latitudinal variation. With the increase in temperature and rainfall, the LN, LP, and leaf nutrient contents increased significantly (p < 0.001). Across life forms, LN at different life forms varied significantly and was positively correlated with soil P content (p < 0.001). The explanatory degree of climatic factors in shaping the spatial variation patterns of LN and N/P was higher than that of the soil nutrient factors, and the spatial variation patterns of the leaf nutrient traits of different life forms were shaped by the synergistic effects of climatic factors and soil nutrient factors.

Glucose metabolism regulates cell growth and affects astaxanthin accumulation in the green algae

Extracts from plants used in Chinese medicine can be good sources of fungicides for agricultural applications. In this study, we separated and identified antifungal compounds from four traditional Chinese medicine extracts and evaluated their antifungal activities

A novel sensitive vapor generation sampling method, nebulized film dielectric barrier discharge (NFDBD) coupled with inductively coupled plasma mass spectrometry (ICP-MS), was developed in this work for simultaneous determination of noble metals (Rh, Pd, Ir, Pt, and Au). In the presence of formic acid, a 5–11 fold improvement in the sampling efficiency of Rh, Pd, Ir, Pt, and Au by NFDBD was achieved compared with conventional nebulization. Under the optimized conditions, the relative standard deviation (RSD) of Rh, Pd, Ir, Pt, and Au determined at 5 μg L−1 was between 1.4% and 4.3%, and the detection limits (LODs) of Rh, Pd, Ir, Pt, and Au were between 0.1 ng L−1 and 0.7 ng L−1. This NFDBD sampling technique not only operates with no requirement of unstable reagents, easy coupling with flow injection, along with high tolerance for coexisting ions, but also achieves lower LODs than the Na(K)BH4–acid vapor generation system and UV photochemical vapor generation system for noble metal determination. This work also extends the scope of elements that can be determined by DBD plasma vapor generation and provides a highly efficient analytical approach for the determination of Rh, Pd, Ir, Pt, and Au in environmental samples, especially in natural water.

Extracts from plants used in Chinese medicine can be good sources of fungicides for agricultural applications. In this study, we separated and identified antifungal compounds from four traditional Chinese medicine extracts and evaluated their antifungal activities in vitro and in vivo. In vitro, honokiol extracted from Artemisia argyi showed broad-spectrum antimicrobial and mycelial inhibitory activity with EC50 in the range 3.56 − 33.85 μg/mL against eight plant pathogens. q-PCR indicated that honokiol might induce cell cancerisation and inhibit cellular respiration, which provided significant insights into honokiol function in tobacco resistance to molecular mechanisms of the phytopathogenic fungus Phytophthora nicotianae. In vivo, honokiol significantly decreased the rate of fungal infection in eggplants, potatoes, grapes, cherry tomatoes, and cucumbers, and enhanced disease resistance in tobacco. Overall, our results indicate that honokiol has the potential to control a variety of fungal and oomycete diseases, and A. argyi could be a source of honokiol.

The state of the microstructures determines both the mechanical properties (hardness, yield strength, elongation, etc.) and micro-magnetic properties (magnetic Barkhausen noise (MBN), incremental permeability (IP), etc.). The non-destructive nature of the micro-magnetic testing technology facilitate it be a valuable tool for quality control in the manufacturing of ferromagnetic components. In the implementation of micro-magnetic testing, the functions and the geometry of the sensors need be customized for specific target properties and components. In this paper, four types of advanced or multifunctional sensors are presented and applied for micro-magnetic testing. First, a multifunctional sensor is developed for flat surface. Unique intermittent magnetizing method using superimposed magnetic fields of high and low frequencies enable the sensor to measure the magnetic Barkhausen noise, incremental permeability, eddy currents, tangential magnetic field and main flux. Second, to conduct magnetic Barkhausen noise testing at the inner corner of V-shape bending plate, a miniaturized sensor with U-shape roller magnetizer is designed to perfect contact with the corner region. Third, read head of a magnetic tape player is revised to act as high-lateral-resolution (up to 500μm) sensor for magnetic Barkhausen noise measurement in ferromagnetic film. Fourth, a slender probe is developed and embedded into an anti-bulking fixture that is clamped onto the flat specimen. With the slender probe together with the special fixture, the dependency of the magnetic Barkhausen noise on the compressive and tensile stress is first experimentally observed in a single flat specimen under continuous load.

The sparse coding method has been successfully applied to multi-frame super-resolution in recent years. In this paper, we propose a new multi-frame super-resolution framework which combines low-rank fusion with sparse coding to improve the performance of multi-frame super-resolution. The proposed method gets the high-resolution image by a three-stage process. First, a fused low-resolution image is obtained from multi-frame image by the method of registration and low-rank fusion. Then, we use the jointly training method to train a pair of learning dictionaries which have good adaptive ability. Finally, we use the learning dictionaries combined with sparse coding theory to realize super-resolution reconstruction of the fused low-resolution image. As the experiment results show, this method can recover the lost high frequency information, and has good robustness.

The Sr2CaWO6: RE3+ (RE = Dy, Sm and Eu) phosphors with the unusual emissions corresponding to the magnetic-dipole (MD) transition were synthesized via a sol-gel process. The crystal structure, electronic properties, photoluminescence excitation and emission spectra, and fluorescence lifetimes of the as-prepared samples were investigated. X-ray diffraction analysis confirmed that Sr2CaWO6 crystallized in the monoclinic structure with the centrosymmetric monoclinic space group (P21/n). The indirect band gap for Sr2CaWO6 was 4.24 eV, which was calculated within the framework of density functional theory (DFT). The phosphors could be excited by the ultra-violet (UV) light at 280 nm, and exhibited characteristic emissions corresponding to the MD transitions for different RE3+ ions. The WO6 groups in the host lattice can absorb UV light efficiently, and then transferred the energy to activator ions. The results indicated that the doped rare earth ions occupied the centrosymmetric site in Sr2CaWO6 lattice. With increasing the concentration of the dopants, the local symmetry of the activator ions can be effectively changed, which resulted in the enhancement of the characteristic emissions dominated by the electric-dipole (ED) transitions of the doped RE3+. The Sr2CaWO6: Sm3+ phosphor exhibited near white emission under radiation of 280 nm.

We report on Ni nanoparticles supported on boron nitride spheres (BNSP) and sheets (BNSH) as catalysts for hydrogen generation via hydrolysis of ammonia borane (NH 3 BH 3 , AB). The Ni/BN catalysts were prepared through a redox replacement reaction. The structure, morphology, and chemical composition of the obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) equipped with energy dispersive X-ray spectroscopy (EDX), and inductively coupled plasma emission spectroscopy (ICP). The characterization results showed that Ni nanoparticles were well dispersed on the BNSP and BNSH supports for the four Ni/BN catalysts prepared (Ni atomic contents of 6.8, 9.0, 9.2, and 12 wt%). The catalytic activity toward the hydrolysis of AB was found to correlate with the loading of the Ni/BN catalysts, which showed great cycle performance. Theoretical calculations revealed that BN sheets significantly influenced the electric character of Ni catalysts and thereby their catalytic properties.

Grain refinement is an effective way to improve the strength of non-heat treatment aluminium alloy. To obtain much refined grains in the spun parts made of 3003 aluminium alloy, a unique spinning method, i.e., repetitive shear spinning, is proposed. The new process is composed of two shear spinning passes conducted along the two sides of sheet metal sequentially. By using finite element (FE) simulation and physical experiment, the grain refinement in the repetitive shear spinning is investigated. The results indicate that, under the same thickness reduction ratio, both the larger equivalent plastic strain and the larger shear strain can be obtained in the repetitive shear spinning than those obtained in the traditional single-pass and two-pass shear spinning processes. Meanwhile, the density of plastic dissipation energy (DPDE) in the repetitive shear spinning process is larger than that in two-pass shear spinning and doubled compared with that in single-pass shear spinning. This makes more deformation energy to be transformed into the stored energy thus provides more driving force for grain refinement. The observation of microstructure indicates that after the repetitive shear spinning, a great number of refined grains are generated with the average grain size refined from 48.6μm of the initial microstructure to 3.77μm, which is smaller than the grain size of 7.17μm and 4.91μm in single-pass and two-pass shear spinning, respectively. With the grain refinement, the micro hardness and its homogeneity of spun part after repetitive shear spinning is improved obviously. Compared with the average standard deviation of micro hardness obtained by the single-pass and two-pass shear spinning, it is decreased by 70.27% and 61.41% under the same thickness reduction ratio. The developed repetitive shear spinning process thus has the good capability for grain refinement and enhancement of mechanical properties of the spun parts and the promising application potential in industries.

The feasibility of 16 types of rare-earth elements (REEs) containing Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu vapor, generated simultaneously, was demonstrated by nebulized film dielectric barrier discharge (NFDBD) in this work. Note that this is the first report on the simultaneous vapor generation of 16 types of REEs, which previously was difficult to realize. Combining it with inductively coupled plasma-mass spectroscopy (ICP-MS) as the sampling technique, a 4-fold to 10-fold improvement in the detection limits (LODs) of the REEs was observed, compared with the conventional solution nebulization, and no obvious interferences from other metal ions and the mutual interferences between REEs at the mg L

Artificial multicellular systems are gaining importance in the field of tissue engineering and regenerative medicine. Reconstruction of complex tissue architectures in vitro is nevertheless challenging, and methods permitting controllable and high-throughput fabrication of complex multicellular architectures are needed. Here, a facile and high-throughput method is developed based on a tunable droplet-fusion technique, allowing programmed assembly of multiple cell spheroids into complex multicellular architectures. The droplet-fusion technique allows for construction of various multicellular architectures (double-spheroids, multi-spheroids, hetero-spheroids) in a miniaturized high-density array format. As an example of application, the propagation of Wnt signaling is investigated within hetero-spheroids formed from two fused Wnt-releasing and Wnt-reporter cell spheroids. The developed method provides an approach for miniaturized, high-throughput construction of complex 3D multicellular architectures and can be applied for studying various biological processes including cell signaling, cancer invasion, embryogenesis, and neural development.

To investigate the grain refinement and its mechanism in shear spinning, microstructures of shear spun parts made by aluminium alloy under different deformation conditions, induced by different shear spinning deviation ratios, are studied. The results show that, after shear spinning, the microstructure is distributed symmetrically about a zone in sheet thickness defined as the neutral zone which is located between the inner surface and the middle plane of spun sheet thickness. Various deviation ratios in shear spinning can lead to grain refinement in different regions along thickness direction of the spun part. The microstructure characteristics indicate that the mechanism of grain refinement is due to the formation of deformation bands (DBs). It is observed that in DBs, parallel geometrically necessary boundaries (GNBs) formed by a zero deviation ratio and crossed GNBs formed by positive and negative deviation ratios are due to the different stress states induced by various deviation ratios in shear spinning. Due to the influence of grain refinement, micro hardness increases with the decreasing of the deviation ratio. The average value is increased by 16.04% under a negative deviation ratio compared to the initial micro hardness of the sheet. Keywords: Grain refinement, Shear spinning, Deformation bands, Deviation ratio, Aluminium alloy

Anti-idiotypic nanobodies (AId-Nbs) are novel antigens that can replace the conventional hapten–protein conjugates of small molecule toxins, serving the same function in the competitive immunoassay. Furthermore, nanobodies show increased sensitivity from naive (non immunized) phage display libraries because those obtained have a lower affinity than the binding affinity of the target analytes. Here, we demonstrated a new approach for the development of sensitive and environmentally friendly immuno-PCR (IPCR) for OTA based on phage displayed AId-Nbs against anti-OTA monoclonal antibodies. In this study, a phage displayed AId-Nb was selected from a naive nanobody library. After four cycles of panning, a phage displayed AId-Nb was isolated using a competition-binding biopanning strategy. The half-inhibition concentration (IC50) of the phage-ELISA was 300 pg mL−1, which was 8.83-fold better than that of a conventional ELISA. Furthermore, a non-toxin quantitative IPCR assay was also developed for the detection of ochratoxin A in agri-products based on phage displayed AId-Nbs. The limit of detection (LOD) of the assay is 4.17 pg mL−1, which exhibits a 9-fold improvement over the phage-ELISA. The developed method was successfully validated using OTA contaminated agri-products. Furthermore, novel and environmentally friendly IPCR might have potential applications in a general method for the immunoassay of various toxic small molecules.

Due to the restrictions of traditional teaching model, serious problems emerge in Comprehensive English teaching, which hamper the practical competence of English major students. Based on the essentials of John Dewey’s pragmatic ideas, this study explores and proposes the 3-dimentional teaching model in Comprehensive English and aims to promote English basic skills, innovative thinking intelligence and professional practical competence of the English major talents.

Device-to-device (D2D) communication has been a significant supplement for traditional cellular network (CN) when meeting with the increasing number of requiring users. In this paper, we assume that cellular user equipments (CUEs) has priority over D2D user equipments (DUEs) on utilizing spectrum resource, and we aim at maximizing the average number of successfully corresponding DUEs. The spatial distribution of requiring users is assumed as homogeneous Poisson Point Process (PPP), therefore it is analytically tractable to derive the expression of D2D communication coverage probability. We derive the approximate closed-form expression of successfully corresponding DUEs' average number, and then obtain the optimal point of the expression with respect to activated DUE's density, and finally verify the effectiveness of this optimal point by numerical results.

Resource allocation in device-to-device (D2D) aided cellular systems, in which the proximity users are allowed to communicate directly with each other without relying on the intervention of base stations (BSs), is investigated. A new uplink resource allocation policy is proposed for enabling the D2D user equipments (DUEs) to reuse the licensed spectrum, provided that the minimum signal-to-interference (SIR) requirement of conventional cellular user equipments (CUEs) is satisfied. Furthermore, the proposed resource-allocation problem can be formulated as “maximizing the number of simultaneously activated D2D pairs subject to the SIR constraints at both CUEs and DUEs”. Numerical results relying on system-level simulation show that the proposed scheme is capable of substantially improving both the D2D-access probability and the network throughput without sacrificing the performance of conventional CUEs.

In this paper, the resource allocation issues in Device-to-Device (D2D) aided heterogeneous networks are investigated, with successive interference cancellation (SIC) capabilities enabled in base stations (BSs). The problem of maximizing the sum throughput of whole network by considering real-time transmissions is formulated. After that, the globally optimal power control is carried out relying on both the enumeration and Kuhn-Munkres methods. To both guarantee the successful transmission probability (STP) of cellular users (CUEs) and reduce the system’s management overhead, a range-difference based resource allocation scheme is proposed. Numerical results show that the average throughput of CUEs can be substantially improved without sacrificing the performance of CUEs by invoking the proposed resource allocation scheme.

The wide band gap of boron nitride (BN) materials has been a major bottleneck for a wider application of BN in electronics. In this work, density functional theory computations were used to study the band structure of zigzag BN nanoribbons (BNNRs). Due to the ionic origin of the BN band gap, a heterogeneous edge decoration is an effective way to modulate the electronic band structure of BNNRs. This study demonstrates that a metallic behavior and magnetism can be realized by applying a NO 2 –NH 2 pair edge decoration. Although the lone electron pair of the NH 2 group is partly responsible for the metallic behavior, the effective potential difference induced by the donor–acceptor pair is also crucial for metallic behavior. Furthermore, these newly formed BNNRs were found to be more stable than H-passivated BNNRs. This simple chemical modification method offers great opportunities for the development of future BNNR-based electronic devices.

Nanobodies that are small and thermally stable, as well as have high expression level, are leading alternative to produce anti-idiotypic antibodies. These antibodies have the advantage of replacing mycotoxins and their conjugates for immunoassays. In this work, anti-fumonisin B1 (FB1) monoclonal antibody (mAb) was used as the target for biopanning from a naive alpaca nanobody (Nb) phage display library. After three cycles of panning, one anti-idiotypic nanobody (Ab2β Nb) was isolated and subjected to a Nb-ELISA for the detection of FB1. Surface plasmon resonance was used to analyze the reaction kinetics between the Ab2β Nb and anti-FB1 mAb. The developed assay showed a half inhibitory concentration (IC50) of 0.95±0.12 ng/mL, a limit of detection of 0.15 ng/mL, a linear range of 0.27-5.92 ng/mL, and a low cross-reactivity toward FB2 of 4.93%. The sensitivity was enhanced approximately 20-fold compared with that of the chemosynthetic FB1-BSA conjugates. The equilibrium dissociation constant (KD) measured for Ab2β Nb: anti-FB1 mAb was 164.6 nM. The assay was compared with conventional ELISA (the commercial ELISA kit), and the results indicated the reliability of Ab2β Nb replacing the antigen-carrier protein conjugates. The use of biotechnology in developing the surrogate is an ideal strategy for replacing conventional synthesized antigens.

Hot spinning process has attracted significant attention because it can be used to manufacture complex parts, extend the forming limit of materials, decrease forming forces and reduce process chains. In this paper, we review researches on lightweight metals spun at elevated temperatures since they are difficult to deform at room temperature. These metals include light alloys, such as titanium, magnesium and aluminum alloys, and metal composites. Then, the heating methods used in the hot spinning process and the treatment methods employed for the temperature boundary condition in finite element analyses for the process were discussed. Finally, the future development directions for the hot spinning process of lightweight but difficult-to-deform alloys were highlighted.

The device-to-device (D2D) communication has been regarded as a promising technique to effectively upgrade the existing cellular network. Despite the intriguing perspectives of D2D technique, the performance of D2D-aided cellular network may degrade owing to the severe interference imposed by newly introduced D2D links. With a motive to deal with this problem, the key performance parameters of D2D-aided underlaying cellular networks, including the coverage probability and total data rate have been investigated. Firstly, we analyze the expressions of coverage probability for both the conventional cellular links and the D2D links, and then we give out the approximate expression of the ergodic rate for both individual links and that of the whole underlaying system. After that, in order to optimize the performance of the system in terms of throughput, more parameters closely related to the channel capacity are studied. Finally, the simulation results revealed that the best values for key parameters (e.g. the density of D2D users) are attainable, and the total data rate can been greatly improved according to our proposed strategies.

Image super-resolution based on learning dictionary has recently attracted enormous interests in the field of image super-resolution. In the general, learning dictionary is trained from a large number of training samples. In this paper, we proposed to use the nonlocal self-similarity to filter blocks that are not similar in structure. Based on the judgment method of structural dissimilarity, we can get a small set of dissimilar training samples and then obtain a pair of high quality Structural Dissimilarity Learning Dictionary (SDLD). Extensive experiments on image super-resolution (SR) are carried out to validate the generality, effectiveness and robustness of the proposed method. Extensive experiments on image super-resolution are carried out to validate the generality, effectiveness and robustness of the proposed method. Experimental results demonstrate that our method can not only reduce the training time largely, but also achieve better results of SR.

In this paper, throughput improvement in device-to-device (D2D) enabled cellular systems is investigated. An uplink resource allocation policy can be implemented, by formulating the reuse relationship as relative position relationship under the constrains of both interference limitation area (ILA) and signal-to-interference-plus-noise ratio (SINR), to find the suitable reuse location relationship between D2D user equipments (DUEs) and cellular user equipments (CUEs). The DUEs can thus be allowed to reuse the licensed spectrum. Furthermore, the proposed resource-allocation algorithm can be readily formulated as an objective function of "maximizing the sum throughput subject to the SINR constrains at both CUEs and DUEs". Numerical results indicate that the proposed algorithm can effectively enhance both the sum throughput and the D2D-access probability (DAP) without seriously impairing the performance of the conventional CUEs.

In this paper, we propose a priority based joint power control and resource allocation algorithm for enhancing the energy efficiency (EE) of device-to-device (D2D) links through enabling the successive interference cancellation (SIC) capabilities at the base stations (BSs). In the power control functional module, the EE-maximization model corresponding to each individual D2D link can be transformed into its equivalent model, in which the objective function is demonstrated to be a concave function of the transmitting power of D2D transmitter and can thus be optimized by implementing joint Bisection and Dinkelbach iterative solution. Inspired by the thought of greedy algorithm, in the radio resource allocation functional module, we propose a priority based resource allocation approach for further reducing the computational complexity of our algorithm. Numerical results show that the proposed approach can substantially improve the EE of the D2D links with rapid converge speed.

A sensitive indirect competitive nanobody-based enzyme linked immunosorbent assay (Nb-ELISA) for ochratoxin A (OTA) with high resistance to cereal matrix interference was developed. Nanobodies against OTA (Nb15, Nb28, Nb32, Nb36) were expressed in E. coli cells and their thermal stabilities were compared with that of an OTA-specific monoclonal antibody 6H8. All nanobodies could still retain their antigen-binding activity after exposure to temperature 95 °C for 5 min or to 90 °C for 75 min. Nb28 that exhibited the highest sensitivity in ELISA was selected for further research. An indirect competitive ELISA based on Nb28 was developed for OTA, with an IC50 of 0.64 ng/mL and a linear range (IC20-IC80) of 0.27–1.47 ng/mL. Cereal samples were analyzed following a 2.5 fold dilution of sample extracts, showing the good resistance to matrix interference of the Nb-ELSIA. The recovery of spiked cereal samples (rice, oats, barley) ranged from 80% to 105% and the Nb-ELISA results of OTA content in naturally contamined samples were in good agreement with those determined by a commercial ELISA kit. The results indicated the reliablity of nanobody as a promising immunoassay reagent for detection of mycotoxins in food matrix and its potential in biosensor development.

Mesangial cells of glomerulus which could produce and degrade several ECMs, take part in the repair and update of mesangial matrix and GBM, regulate glomerular filtration rate, secret cytokines and phagocytose immune complexes contribute a lot to physiological functions and pathological reactions of glomerular. There inflammation response of abnormal proliferation induced by LPS could lead to renal damage. Herein, wedelolactone, an active chemical constituent extracted from leaves of Eclipta alba, was used to explore if it could be an effective inhibitor of the proliferative response of HRMCs. The effects of different concentration wedelolactone on the secretion of cytokines, cell viability and NF-κB pathway were all detected by qPCR, western blotting and ELISA. The results indicated that wedelolactone could inhibit the abnormal proliferation of HRMCs via regulating the activity of several key members of NF-κB signaling pathway.

Tools such as agricultural grass cutters, stubble blades, machetes, and grain crushing knives can become passivated gradually during use without self-sharpening. To resolve this problem, a composite coating of a Ni-based alloy and tungsten carbide (WC) was brazed onto the unilateral surface of 45 steel tools. To ensure that the unilateral coating tool can self-sharpen, different heat treatments were tested that can change the microstructure of the substrate. This makes it possible to regulate the wear resistance on both sides of the tool. Previous research shows that multiple phases can coexist at the interface between WC and Ni-based brazing alloys. These can decrease the initial melting temperature and the finishing melting temperature of the coating by 30.7°C and 49°C, respectively. A quantitative wear test of the tool indicates that the material-removal rate of the coating and the substrate is inversely proportional to its hardness. As a result, the optimal coating thickness can be estimated using the material-removal rate, i.e., the wear. A plowing simulation in gravel shows that after long-time usage (for example, 100 h), the tool, which was treated with quenching/tempering, is very good at self-sharpening. Moreover, the shortening in the direction of the symmetry line of the tool is small. The aim of the study is to improve both self-sharpening and service life of the tools.

This paper proposes a new multiple sparse dictionary model, and realizes super-resolution reconstruction via the multiple sparse dictionary combined with sparse coding, which can improve the resolution of image. The training sample set is constructed by image patches wavelet transform to extract the horizontal, vertical, diagonal and high-frequency information of approximate part composition column feature vectors. Then, calculating a pair of learning dictionary via multiple sparse dictionary which trained by the sparse K-singular value decomposition algorithm. Finally, combining the learning dictionaries and sparse coding theory to realize the image super-resolution reconstruction. As the experiment results show, the new method has good performance for recovering the lost high-frequency information, and has good robustness.

In this paper, the capacity of underlaying cellular networks is analyzed by considering the impact of Device-to-Device (D2D) mode, which is shown to be capable of substantially enhancing the sum transmission rate of the cellular network. Based on the theory of stochastic geometry, the successful transmission probabilities of both the D2D users and the conventional cellular users(CUs) are derived, with the D2D transmission rate as well as the sum rate given out simultaneously. Furthermore, the optimal D2D-users(DUs) density that maximizes the sum rate is also derived. In addition, we extend the analysis from single-cell scenario to the multicell environment. Numerical results demonstrate the relationship between D2D-contributed capacity and the D2D-users density. It is shown that the network capacity can be enhanced by increasing the density D2D users when the D2D-users density is relatively low, until a break-even point is approach, in which case further increasing D2D users may even erode the sum rate.

Immunoassay is frequently used to analyze mycotoxin contamination. However, the introduction of mycotoxins or their conjugates in conventional immunoassay threatens the safety of individuals and the environment. The variable domain of heavy-chain antibodies (VHHs) can be used as alternative compounds to produce anti-idiotypic antibodies, which work as non-toxic surrogate reagents in immunoassay. In this work, anti-zearalenone (ZEN) monoclonal antibody (mAb) was used as the target for biopanning anti-idiotypic VHH from a naive alpaca VHH phage display library. After four panning cycles, one anti-idiotypic VHH phage clone (Z1) was isolated and the Z1 based phage ELISA for ZEN showed a half inhibitory concentration (IC50) of 0.25±0.02ng/mL, a linear range of 0.11-0.55ng/mL, and a limit of detection (LOD) of 0.08ng/mL. Furthermore, the phage particles of Z1 were also applied to immuno-polymerase chain reaction (PD-IPCR), which supplied both the detection antigens and deoxyribonucleic acid (DNA) templates. Compared with that of phage ELISA, the LOD of Z1 based PD-IPCR was 12-fold improved, with a detection limit of 6.5pg/mL and a linear range of 0.01-100ng/mL. The proposed method was then validated with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results showed the reliability of PD-IPCR for the determination of ZEN in cereal samples. The use of anti-idiotypic VHH phage as non-toxic surrogate and signal-amplification function of PCR make it a promising method for actual ZEN analysis in cereals.

Nanobodies that are small and thermally stable, as well as have high expression level, are leading alternative to produce anti-idiotypic antibodies. These antibodies have the advantage of replacing mycotoxins and their conjugates for immunoassays. In this work, anti-fumonisin B1 (FB1) monoclonal antibody (mAb) was used as the target for biopanning from a naïve alpaca nanobody (Nb) phage display library. After three cycles of panning, one anti-idiotypic nanobody (Ab2β Nb) was isolated and subjected to a Nb-ELISA for the detection of FB1. Surface plasmon resonance was used to analyze the reaction kinetics between the Ab2β Nb and anti-FB1 mAb. The developed assay showed a half inhibitory concentration (IC50) of 0.95±0.12 ng/mL, a limit of detection of 0.15 ng/mL, a linear range of 0.27-5.92 ng/mL, and a low cross-reactivity toward FB2 of 4.93%. The sensitivity was enhanced approximately 20-fold compared with that of the chemosynthetic FB1-BSA conjugates. The equilibrium dissociation constant (KD) measured for Ab2β Nb: anti-FB1 mAb was 164.6 nM. The assay was compared with conventional ELISA (the commercial ELISA kit), and the results indicated the reliability of Ab2β Nb replacing the antigen-carrier protein conjugates. The use of biotechnology in developing the surrogate is an ideal strategy for replacing conventional synthesized antigens.

This paper reveals the definition, connotation and significance of critical thinking. It further improves and explores approaches to develop students’ critical thinking capability through Comprehensive English teaching and verifies the validity of those approaches through Comprehensive English class implementation and students’ class presentation. However, it also suggests that developing critical thinking of instructors shall be prioritized before cultivating that of students’, which is worth reflecting in the long run.

On the analysis of major writing devices of “A Dill Pickle” as symbolism, stream of consciousness and further contrasting heroine and the hero of A Dill Pickle, the paper aims to find out the essence of love that true love maintains its passion and dynamism through mutual trust and the art of communication in case that love should fade away over years like the tasteless pickles.