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This study aims to study the distribution characteristics of antibiotic resistance in direct-eating food and analysis of Citrobacter freundii genome and pathogenicity. Residual antibiotics and antibiotic resistance genes (ARGs) in the environment severely threaten human health and the ecological environment. The diseases caused by foodborne pathogenic bacteria are increasing daily, and the enhancement of antibiotic resistance of pathogenic bacteria poses many difficulties in the treatment of disease.

In this study, six fresh fruits and vegetable samples were selected for isolation and identification of culturable bacteria and analysis of antibiotic resistance. The whole genome of Citrobacter freundii isolated from cucumber was sequenced and analyzed by Oxford Nanopore sequencing.

The results show that 270 strains of bacteria were identified in 6 samples. From 12 samples of direct food, 2 kinds of probiotics and 10 kinds of opportunistic pathogens were screened. The proportion of Citrobacter freundii screened from cucumber was significantly higher than that from other samples, and it showed resistance to a variety of antibiotics. Whole genome sequencing showed that Citrobacter freundii was composed of a circular chromosome containing signal peptides, transmembrane proteins and transporters that could induce antibiotic efflux, indicating that Citrobacter freundii had strong adaptability to the environment. The detection of genes encoding carbohydrate active enzymes is more beneficial to the growth and reproduction of Citrobacter freundii in crops. A total of 29 kinds of ARGs were detected in Citrobacter freundii, mainly conferring resistance to fluoroquinolones, aminoglycosides, carbapenem, cephalosporins and macrolides. The main mechanisms are the change in antibiotic targets and efflux pumps, the change in cell permeability and the inactivation of antibiotics and the detection of virulence factors and ARGs, further indicating the serious risk to human health.

The detection of genomic islands and prophages increases the risk of horizontal transfer of virulence factors and ARGs, which spreads the drug resistance of bacteria and pathogenic bacteria more widely.

In this study, the Models-3/Community Multiscale Air Quality Model (CMAQ) coupled with the Mesoscale Modeling System Generation 5 (MM5) was employed to simulate the air pollution episodes over East Asia, northern China Plain (NCP), and southern Hebei (SHB), at a grid resolution of 36, 12, and 4 km, respectively in Oct. 2012. The PM₁₀ concentrations over SHB at 12-km are overpredicted with NMBs of 34.6% to 45.7% and also overestimated with that of 72.1% to 97.5% at 4-km which applied such a fine grid resolution over the SHB for the first time. It indicated that the simulation at 12-km performs better than the 4-km which may be related to the spatial allocation of the emissions, the lack of dust emissions and the limitations of model treatments. Five heavy episodes show the characteristics of sawtooth-shaped cycles over the NCP in fall (i.e. the maximum of PM₁₀ was up to 885.1 µg m⁻³ and PM_2.5 was up to 438.4 µg m⁻³ in Handan city) which resulting in the deterioration of visibility and periodically haze days. The concentrations of OC, EC, SO₄²⁻, NO₃⁻ and NH₄⁺ were significantly higher in heavy episodes than non-heavy pollution episodes. In comparison with other cities ([NO₃⁻]/[SO₄²⁻] > 1) at 12-km, the monthly-mean mass ratio of [NO₃⁻]/[SO₄²⁻] at Taiyuan (0.17−0.73), Shijiazhuang (0.28−2.34) was 0.43, 0.84 respectively, which means the stationary sources emissions were more important than the vehicle emission in the source areas. The influence of the regional transportation for pollutants compared with local emission was also an important factor for heavy pollution episodes. The regional joint framework should be established along with controlling the local emission over the SHB in China to improve the air quality.

This paper aims to explore the interplay between industrial diversity and sustainable economic development in US counties.

Among other popularly used measures, this study uses an underused measure, Hachman index, to gauge the degree of industrial diversity in the models. To capture the impact of industrial diversity on the local community, this study estimates the relationship of two diversity measures to four traditional socioeconomic indicators: per capita personal income growth, gross domestic product per worker, income inequality ratio and poverty rate.

Statistical results suggest that industrial diversity, which is measured by Hachman index, is significantly related to the four socio-economic indicators. Industrial diversity can positively contribute to regional per capita personal income growth and mitigate income inequality and poverty stress; however, it is negatively related to the gross domestic product (GDP) per worker, which means industrial specialization may contribute to GDP per worker growth.

The findings of this study show that there is a nonlinear relationship between industrial diversity and all socioeconomic indicators. Most of the control variables, human capital variables and business and industry profile variables also display significant and positive impacts on economic development.

Thiadiazole compounds and their derivatives have carrying capacity and good lubricating properties. However, their poor oil-solubility limited their wide usage in lubricating oil. The study aims to develop thiadiazole lubricant additives with better oil-solubility. When the hindered phenol antioxidation functional group and alkyl-chain are introduced to thiadiazole, the resulting product could have better oil-solubility and excellent antioxidation resistance, anti-wear and corrosion resistance in the lubricating oil.

One kind of thiadiazole lubricant additive, for the first time, has been synthesized from 2,5-dimercapto-1,3,4-thiadiazole. Its tribological performance has also been evaluated by four-ball test. And, its oxidation resistance has been estimated by rotating pressure vessel oxidation test and pressurized differential scanning calorimetry. The anticorrosion performance of such an additive has been studied by GB/T 5096 standard method test.

The synthesized thiadiazole additive has excellent anti-oxidation capability, good anti-wear and extreme pressure properties and good anticorrosion performance, in comparison with zinc dialkyl dithiophosphate (ZDDP). In base oils, the comprehensive performance of thiadiazole additive is comparable to ZDDP. Mechanistic studies indicate that the S and N active elements were involved in the formation of a boundary film. This may account for the formation of a composite membrane on the metal surface and thus for the tribological performance of such thiadiazole additives.

The thiadiazole derivatives, which are ashless and have environmentally friendly features, are a potential alternative to ZDDP. Because of the film formed on the friction surface, thiadiazole compounds may serve as an excellent anti-wear additive and are expected to reduce friction and wear between metals.

In a risk analysis system, different underlying indices often play different roles in identifying the risk scale of the total target in a system, so a concept of discriminatory weight is introduced first. With the help of discriminatory weight and membership functions, a new method for information security risk analysis is proposed. The purpose of this paper is to discuss the above issues.

First, a concept of discriminatory weight is introduced. Second, with the help of fuzzy sets, risk scales are captured in terms of fuzzy sets (namely their membership functions). Third, a new risk analysis method involving discriminatory weights is proposed to realize a transformation from the membership degrees of the underlying indices to the membership degrees of the total target. At last, an example of information security risk analysis shows the effectiveness and feasibleness of the new method.

The new method generalizes the weighted-average method. The comparative analysis done with respect to other two methods show that the proposed method exhibits higher classification accuracy. Therefore, the proposed method can be applied to other risk analysis system with a hierarchial.

This paper proposes a new method for information security risk analysis with the help of membership functions and the concept of discriminatory weight. The new method generalizes the weighted-average method. Comparative analysis done with respect to other two methods show that the proposed method exhibits higher classification accuracy in E-government information security system. What is more, the proposed method can be applied to other risk analysis system with a hierarchial.

The purpose of this paper is to present a more objective evaluation method for a mining area ecological environment. It proposes the weight of indices with respect to the total goal, and provides a new evaluation method which generalizes the weighted‐average method.

First, the authors describe the evaluation grades by fuzzy variables in credibility space, and the degree of an index belonging to a grade is transformed to be the credibility measure of a fuzzy event by the credibility inversion theorem. Second, a new algorithm which generalizes the weighted‐average method is proposed to realize the transformation from the credibility degree of the underlying indices to the credibility degree of the total target.

The method proposed in this paper can obtain the correct results illustrated with a numerical evaluation example. The comparison with two other methods shows that the proposed method has stronger classification ability.

The new method presented in this paper generalizes the weighted‐average method, and provides methods for other evaluation systems with a hierarchical structure.

When designing the electrode widths of the electrode-width-weighted (EWW) input interdigital transducers (IDTs) according to the envelope amplitudes of the wavelet function, the EWW wavelet transform processor (WTP) using surface acoustic wave (SAW) devices can be fabricated. The electrode widths have influence on the frequency characteristic of the EWW WTP using SAW devices. The purpose of this research is to solve the influence of the electrode width accuracy on the frequency characteristic of the EWW WTP using SAW devices.

In order to solve the influence of the electrode width accuracy on the frequency characteristics of the EWW WTP using SAW devices, the function between the electrode widths and the −3 dB bandwidth is derived. That the −3 dB bandwidth varies as the electrode widths is known according to this function so that the exposure time and the etching are presented as the two key problems.

Solutions to these problems are achieved in this study. As long as there is accurate exposure time, the precision IDTs (i.e. the precision electrode widths) will be obtained. The accuracy of the exposure time for the EWW WTP using SAW devices is ±1 per cent. Because the dry etching is a type of etching technology in gas medium, it can etch nanometer lines, even more fine lines, so that the dry etching is used in EWW WTP using SAW devices.

Research highlights solving the influence of the electrode width accuracy on the frequency characteristic for the EWW WTP using SAW devices; deriving the function between the electrode widths and the −3 dB bandwidth (it is known from this function that the −3 dB bandwidth varies as the electrode widths); and presenting the exposure time and the etching as two key problems.

The study aims to elaborate the author’s basic viewpoints on how economics should view the Internet from four aspects.

This paper reviews the existing literature on this topic, and summarizes key findings and conclusions of these researches.

The findings include four major contradictions in economics brought by the Internet, and 12 new changes in economics that needs to be addressed.

This paper provides a clear summary of existing studies on economics’ views of the internet and a prospect for future internet economy research.

This paper aims to review recent advances and applications of abrasive processes for microelectronics fabrications.

More than 80 patents and journal and conference articles published recently are reviewed. The topics covered are chemical mechanical polishing (CMP) for semiconductor devices, key/additional process conditions for CMP, and polishing and grinding for microelectronics fabrications and fan-out wafer level packages (FOWLPs).

Many reviewed articles reported advanced CMP for semiconductor device fabrications and innovative research studies on CMP slurry and abrasives. The surface finish, sub-surface damage and the strength of wafers are important issues. The defects on wafer surfaces induced by grinding/polishing would affect the stability of diced ultra-thin chips. Fracture strengths of wafers are dependent on the damage structure induced during dicing or grinding. Different thinning processes can reduce or enhance the fracture strength of wafers. In the FOWLP technology, grinding or CMP is conducted at several key steps. Challenges come from back-grinding and the wafer warpage. As the Si chips of the over-molded FOWLPs are very thin, wafer grinding becomes critical. The strength of the FOWLPs is significantly affected by grinding.

This paper attempts to provide an introduction to recent developments and the trends in abrasive processes for microelectronics manufacturing. With the references provided, readers may explore more deeply by reading the original articles. Original suggestions for future research work are also provided.

The purpose of this paper is to study the spectral sensitivity characteristics of new pyroelectric sensor based on tetraaminodiphenyl film within the wavelength range of 0.4-10 µm and 300-3,000 µm.

Mylar film with the thickness of about 70 µm was used as the input window. The MDR-41 monochromator-based spectrometric complex and the quasi-optical spectrometer with the set of backward-wave oscillators were used for measurements of the pyrodetector spectral characteristics within the 0.4-10 µm and 300-3,000 µm ranges, respectively.

Mylar was found to have absorption lines within the range of 0.4-10 µm, which must be taken into account when broadband detectors developing. The noise equivalent power in the visible and infrared ranges was less than 6 × 10^–10 W/Hz^1/2, which is about five times lower than for analogue ones. In the sub-THz range, the pyrodetector sensitivity is 2-8 times higher than the Golay cell. The sensitivity of such pyrodetector weakly depends on the wavelength in the total measured range.

The pyroelectric sensor has good prospects for use in super wide spectral range, from ultraviolet to millimeter radiation, in spectrometers for scientific research, in industry for the operational control of THz radiation sources, as well as in security THz-systems.

The spectral sensitivity characteristics of the pyroelectric photosensor based on TADPh in the visible, infrared and terahertz ranges were measured. The prospects for the use of such sensors were determined.