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Methane-oxidizing bacteria (MOB) are a unique group of gram-negative bacteria that are proved to be biological indicator for gas prospecting since they utilize methane as a sole source of carbon and energy. Herein the feasibility of a novel and efficient gas prospecting method using Raman spectroscopy is studied. Confocal Raman spectroscopy is utilized to establish a Raman database of 11 species of methanotrophs and other closely related bacteria with similar morphology that generally coexist in the upper soil of natural gas. After strict and consistent spectral preprocessing, Raman spectra from the whole cell area are analyzed using the combination of principal component analysis (PCA) and Mahalanobis distance (MD) that allow unambiguous classification of the different cell types with an accuracy of 95.91%. The discrimination model based on multivariate analysis is further evaluated by classifying Raman spectra from independently cultivated bacteria, and achieves an overall accuracy of 94.04% on species level. Our approach using Raman spectroscopy in combination with statistical analysis of various gas reservoirs related bacteria provides rapid distinction that can potentially play a vital role in gas exploration.

Parliamentary texts are records of discussions of domestic and international affairs, which reflect national attitudes and development trends in foreign relations. In this paper, a research framework is proposed to analyze foreign relations on the basis of parliamentary texts. First, topic words are extracted from parliamentary texts, and then a co-word network is constructed to represent the correlation structure of topic words. The basic statistics, calculation of network indicators, community detection, and visualization of network maps and evolution venation, as well as the depiction of a strategic diagram, elucidate deeper characteristics and connotations of foreign relations. This case study on UK-China relations during the period of 2011-2017 using British parliamentary texts reveals the following findings. Over this period, UK-China relations changed in terms of the topics involved, topics which are greatly unbalanced in distribution, but are quite concentrated. Five different directions exist, centering on Trade, Human rights, Nuclear, Steel, and Visa. The evolution of topics includes merging and differentiation. A minority of topics exhibit marked continuity, which constitute the main focal points discussed each year, such as Economy and Trade. Regarding development trends, themes related to trade and steel remain focal points in UK-China relations. Overall, the framework proposed in this paper is proven to be both effective and feasible, and its application through this case study can foster a deeper understanding of the status and development of UK-China relations.

A piezoelectric immunosensor has been developed for the detection of complement C4. Anti-C4 antibody was immobilized onto the gold electrodes of a 9 MHz AT-cut piezoelectric crystal. The coated crystal with the physical adsorption method to immobilize antibody showed the better results than the polyethyleneimine adhesion, glutaraldehyde cross-linking method with respect to sensitivity and reproducibility. The antibody-bound crystal with the physical adsorption method was successfully used for the detection of human complement C4 in the concentration range of 0.1—10 μg/mL for 40 min incubation time. The immunosensor system had good selectivity, and other materials in human Serum did not interfere the detection remarkably. The crystal could be regenerated nearly 15 times when the bound materials on the crystal surface were eluted by strong acid and strong alkali solutions and subsequently cleaned in a ultrasonic cleaner.

Liquid crystals of biomolecules occur ubiquitously in biological systems, and to study the physiological mechanism of acupuncture, methods involving the detection of liquid crystals have been introduced. It is revealed that liquid crystals appear in the acupuncture point Zusanli 15 min after the appropriate stimulus in the acupuncture point Jiexi, which is located on the same meridian with Zusanli according to the Meridian Theory of Chinese Medicine, whereas liquid crystals are rarely observed in the points beside the Zusanli in the same condition. Subsequent studies on the composition of the liquid crystals detected, using energy dispersive X-ray analysis and histochemical analysis, suggest that the liquid crystals consist of proteins and perhaps phospholipids. The results show that these biomolecules, which are accumulated in the extracellular fluid of the acupuncture point, may function in the acupuncture effects, and moreover that liquid crystal detection can serve as a simple method to start studies ...

Copper (II) zinc (II) cobalt (III) complexes with the Schiff base derived from salicylaldehyde andd-glucosamine were synthesized. These compounds abbreviated as SG, CuSG, ZnSG, CoSG were characterized by elemental analyses, IR, UV-Vis,1H NMR and MS spectrum. ESR spectrum, magnetic susceptibility measured by Evans method for CuSG had also been done. It is suggested that the complexes in solution have pseudotetrahedral structure. It was found that SG would occur a photochemical reaction if a beach of 355 nm ultravisible light shone on its aqueous solution. The reaction was in further research.

The detection of human fibrin has been performed by immunological piezoelectric quartz crystal microbalance technique. Anti-fibrin antibody was immobilized onto the gold electrodes of a 9 MHz AT-cut piezoelectric quartz crystal with bovine serum albumin adsorption, followed by glutaraldehyde cross-linking. The antibody-bound crystals had good response to human fibrin in the concentration range of 10−4∼10−1g/L. The sensor system had good selectivity. The crystal could be regenerated nearly 10 times without detectable decrease of sensitivity.

A new method of determination of trace CN− in water was proposed. A thin film of Ag2S was electrochemically deposited on both sides of a silver coated piezoelectric crystal. The Ag2S−Ag films can react with CN− selectively, which causes the frequency shifts of the plezoelectric crystal. The frequency shifts are proportional to the concentration of CN− in the range of 10−6≈10−3 g/L. XPS experiments indicated the sensing film was Ag2S−Ag. A coordination complex Ag−CN− was formed when Ag2S−Ag film contacted with solution containing CN− ion. A response mechanism was proposed based on the XPS data.

The international labor division has changed a lot. In the global value chain background, industries spanned country boundaries, which changed the nature of country's participation in international division. Against the backdrop of global value chain, the by-country industrial competitiveness evaluation system based on final products is failing. This paper argued that the research should focus on the corporation itself, and measure the contribution of different types of firms. Using global value chain theory, this article investigates the international competitiveness of China's apparel industry.

The theory of Meridians is an important part of Traditional Chinese Medicine. Modern science should play its role in analysing and making clear the mystique of the theory. The relation between the activities of liquid crystals in acupuncture points and the regulative actions of Meridians was studied in this paper. The results showed the intimate intrinsic association between them.