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旨在为生物处理黄曲霉毒素污染的粮食饲料提供技术支持，以活性炭（SH）为原料进行改性制备磁性活性炭（CSH），选用能高效降解黄曲霉毒素B1（AFB1）的芽孢杆菌属菌株WTX1与CSH载体共培养构建磁性菌载体（FCSH），脱除受污染玉米中的AFB1，对CSH进行BET比表面积、氮吸附-脱附等温线及其对AFB1的等温吸附曲线分析，考察FCSH构建条件和FCSH吸附条件对AFB1脱除效果的影响，并利用傅里叶变换红外光谱（FTIR）和扫描电镜对吸附AFB1前后的FCSH进行表征。结果表明：CSH为大孔结构，其对AFB1的等温吸附符合Freundlich方程；在固定化时间16 h、固定化转速和吸附转速160 r/min、固定化温度和吸附温度35 ℃、吸附pH 8、振荡时间48 h条件下，FCSH对AFB1脱除率为97.45%；通过FTIR及扫描电镜证实了FCSH对AFB1的吸附作用，且FCSH对AFB1的吸附效果强于CSH。综上，所制备的FCSH能高效脱除玉米中的AFB1。Aiming to provide technical support for biological treatment of aflatoxin-contaminated grain feed, magnetic activated carbon (CSH) was prepared through modification from activated carbon(SH), and the strain of Bacillus spp. WTX1, which was capable of efficiently degrading aflatoxin B1 (AFB1), was selected to co-culture with the CSH carrier to construct the magnetic bacterial carrier (FCSH) for the removal of AFB1 from contaminated maize. BET specific surface area, nitroqen adsorption-desorption isotherms and isotherm adsorption curves for AFB1 of CSH were analyzed, and the effect of FCSH construction conditions and FCSH adsorption conditions on the effect of AFB1 removal were investigated. Fourier transform infrared spectrum (FTIR) and scanning electron microscope were used to characterize FCSH before and after adsorption of AFB1. The results showed that CSH had a macroporous structure, and its isothermal adsorption of AFB1 conformed to the Freundlich equation. The removal rate of AFB1 by FCSH could reach 97.45% under the conditions of immobilization time 16 h, immobilization and adsorption speed 160 r/min, immobilization and adsorption temperature 35 ℃, adsorption pH 8, and shaking time 48 h. The adsorption of FCSH on AFB1 was confirmed by FTIR and scanning electron microscope, and the adsorption effect of FCSH on AFB1 was stronger than that of CSH.In conclusion, the prepared FCSH can effectively remove AFB1 from maize.

[Objective] The desert plant Karelinia caspia has a broad-spectrum of stress resistance, including salt/alkali tolerance and high temperature tolerance, which is a precious natural plant germplasm native to Xinjiang. It has been noted that mining the genes involved in extreme temperature and salt tolerance of K . caspia as well as analyzing their expression under stress is critical for using these genes to enhance crop stress resistance, increase yield, and promote the exploration and utilization of the genetic resources of the desert plants. [Methods] Potted K . caspia seedlings were subjected to different durations of high temperature (45 ℃), low temperature (4 ℃), and high salt (400 mmol/L Na+ ) stress. Root, stem, and leaf tissues were collected to analyze the expression of the HTR gene family (KcHTRs) by using RT-PCR and other techniques, and analyze their stress resistance and optimal induction conditions for protein expression by a prokaryotic expression system. [Results] (1) Seven of the KcHTR gene family members were screened and cloned from the transcriptomic data obtained from high temperature treatments of K . caspia. By constructing prokaryotic expression vectors and inducing expression, cDNA lengths of the KCHTR gene family were determined to be between 708 and 789 bp, and the molecular weights of the expressed protein was between 27 and 29 kD. (2) It was found that the optimal expression system of E. coli BL21 was 0.8 at OD600, IPTG concentration 0.5 mmol/L, and induction time 8-10 h at the optimum temperature of 37 ℃. (3) Recombinant E. coli was treated with simulated high temperature, low temperature and salt stress, and the results showed that KcHTRs enhanced the host tolerance to the stresses to certain extent. [Conclusion] The results showed that KcHTRs has broad-spectrum of stress resistance, mainly extreme temperature, and actively responds to stress conditions.

ObjectiveThe study utilized human transcriptome microarray to explore biomarkers for diagnosing drug-induced liver injury （DILI） caused by anti-tuberculosis drugs.MethodsA 6-month follow-up study was conducted on 152 patients treated with anti-tuberculosis drugs in designated hospitals in Shanghai. The blood samples were collected at the 0， 2， 4， 8， 12 and 24 weeks after treatment. According to the clinical biochemical indicators， the research subjects were divided into DILI cases （34 cases） and Control cases （118 cases）. Single factor analysis was conducted on the influencing factors between the two groups. In a 1∶1 matched DILI-control study， RNA samples of 13 pairs of cases were sequenced by the whole transcript expression mRNA array. Differentially expressed genes （DEGs） were screened by Hotelling's T2 value sequencing and the expression trend analysis of genes by STEM （short-time series expression miner）， and the functional enrichment and pathway analysis of DEGs were carried out.ResultsIn total 152 clinical cases， weight of patients was a risk factor for the occurrence of hepatotoxicity caused by anti-tuberculous drugs. Based on the analysis results of mRNA array， 513 DEGs were screened by Hotelling's T2 value sequencing method， which were enriched in 32 annotations of GO （Gene Ontology） analysis and 10 pathways of KEGG （Kyoto encyclopedia of genes and genomes） analysis. One differential expression pattern was screened by STEM， which was enriched in 2 biological process notes of GO. Among them， the key genes AIM2， CD86， CXCL10 and non-coding RNAs SCARNA10， SNHG10 and SNORD105 are potential biomarkers of DILI caused by anti-tuberculosis drugs.ConclusionIn this research for biomarkers conducted on cases with liver injury caused by anti-tuberculosis drugs， biological pathways associated with hepatotoxicity are identified and a series of key genes related with drug-induced liver injury are found， which provides the basis for mechanism study and searching for earlier and more sensitive biomarkers.

In this paper, the mechanical models of large-scale double row slewing ball bearing considering combined loading conditions were presented based on the rigid rings and flexible rings, respectively. And the contact properties between the ball and raceway were studied. These workflows for the calculation were described and programmed by MATLAB. The load distributions of slewing bearing for 2MW wind turbine were presented. The results indicated that the load distribution with the ideal stiff assumption differs from the load distribution determined by taking into account the flexibility of rings. With flexible rings, the magnitude of contact force is less than that of the rigid rings. The influences of the initial contact angle, the coefficient of groove curvature radius, the clearance on maximum contact force were analyzed and some suggestions have been discussed. These parameters have significant effects on the load distribution. The maximum contact force decreases with coefficient of groove curvature radius decrease. A three dimensional finite element model of the slewing bearing is established and analyzed. The simulated results are compared with that of mechanical models.

At present, the conventional construction project cost prediction method mainly constructs the cost prediction model by quantifying the engineering information, which leads to poor prediction effect due to the lack of construction of cost prediction index system. In this regard, the research of construction cost prediction model based on recurrent neural network is proposed. By classifying and integrating the construction project cost concepts, constructing the prediction index system, combining with the recurrent neural network algorithm, constructing the excitation function and calculating the initialization threshold, and finally constructing the prediction model. In the experiment, the proposed method is verified for the prediction accuracy. After the experiments, it can be proved that when the proposed model is used to predict the engineering cost, the root mean square error of the model output is small and has a more ideal prediction accuracy.

The current conventional cost manage- ment model of power grid operation has the problem of single cost apportionment standard, which leads to the poor attribution accuracy. In this regard, the cost attribution method of grid equipment maintenance cost under multi-dimensional lean management mode is proposed. The whole life cycle cost of grid equipment operation is analyzed, and the total cost of grid equipment asset operation and maintenance is calculated, and finally, the operation cost method is used to construct the cost attribution model of maintenance cost. The analysis of the experimental results shows that when the proposed method is used to attribute the maintenance cost cost, the attribution error value of the method is low and has a more desirable cost attribution effect.

Self-accelerating beams show considerable captivating phenomena and applications owing to their transverse acceleration, diffraction-free and self-healing properties in free space. Metasurfaces consisting of dielectric or metallic subwavelength structures attract enormous attention to acquire self-accelerating beams, owing to their extraordinary capabilities in the arbitrary control of electromagnetic waves. However, because the self-accelerating beam generator possesses a large phase gradient, traditional discrete metasurfaces suffer from insufficient phase sampling, leading to a low efficiency and narrow spectral band. To overcome this limitation, a versatile platform of catenary-inspired dielectric metasurfaces is proposed to endow arbitrary continuous wavefronts. A high diffraction efficiency approaching 100% is obtained in a wide spectral range from 9 to 13 μm. As a proof-of-concept demonstration, the broadband, high-efficiency and high-quality self-accelerating beam generation is experimentally verified in the infrared band. Furthermore, the chiral response of the proposed metasurfaces enables the spin-controlled beam acceleration. Considering these superior performances, this design methodology may find wide applications in particle manipulation, high-resolution imaging, optical vortex generation, and so forth.

Broadband sound absorption at low frequency is notoriously difficult because the thickness of the absorber should be proportional to the working wavelength. Here we report an acoustic metasurface absorber following the recent theory developed for electromagnetics. We first show that there is an intrinsic analogy between the impedance description of sound and electromagnetic metasurfaces. Subsequently, we demonstrated that the classic Salisbury and Jaumann absorbers can be realized for acoustic applications with the aid of micro-perforated plates. Finally, the concept of coherent perfect absorption is introduced to achieve ultrathin and ultra-broadband sound absorbers. We anticipate that the approach proposed here can provide helpful guidance for the design of future acoustic and electromagnetic devices.

Standardization for environmental protection in the transportation industry is an important driving force for the development of green transportation. This study introduces the current status and main problems of environmental protection standardization in transportation. In addition, major countermeasures, such as strengthening the system construction and basic support, are studied and proposed to provide theoretical support and research basis for future standardization in related areas.

Noise barrier treatment is a traffic noise pollution prevention project. Many domestic residents along high-grade highways are densely distributed and there are many sensitive points in the acoustic environment. Traffic noise will have a large environmental impact along the route. The design of the noise barrier from the EIA stage to the construction stage is inconsistent with the actual situation. Therefore, in order to improve and optimize the noise reduction measures along the line and reasonably control the cost of the noise barrier project, many should be optimized. We shoud clarify the noise barrier installation location, scale, acoustic material technical requirements, standards, and engineering cost estimates, focusing on the principle of no reduction in noise reduction, strong operability, and economical practicality, in order to highlight the purpose of reducing costs and increasing efficiency.

We mainly study the global behavior of the nonlinear difference equation in the title, that is, the global asymptotical stability of zero equilibrium, the existence of unbounded solutions, the existence of period two solutions, the existence of oscillatory solutions, the existence, and asymptotic behavior of non-oscillatory solutions of the equation. Our results extend and generalize the known ones.