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DNA methylation is one of the essential epigenetic mechanisms that are closely correlated with the mechanisms underlying cell growth, differentiation and transformation in eukaryotes. Global changes in the epigenetic landscape are considered to be a hallmark of cancer. The initiation and progression of cancer are mediated through epigenetic modifications along with genetic alterations. Aberrant methylation of promoter regions is an epigenetic abnormality of the human genome that is highly characteristic of cancer. In this review, we aimed to summarize our current understanding of the alterations in the epigenetic landscape and investigate the potential use of DNA and RNA methylation in effective molecular treatment strategies. [ABSTRACT FROM AUTHOR]

In this study, we used a UV radiation grafting method to modify the surface of the biomaterial polycarbonateurethane (PCU). Hydrophilic poly(ethylene glycol) monoacrylate (PEGMA; number‐average molecular weight = 526) as a macromolecular monomer was grafted onto the PCU surface by UV photopolymerization. The Fourier transform infrared and X‐ray photoelectron spectroscopy results of the graft‐modified PCU confirmed poly[poly(ethylene glycol) monoacrylate] block grafting onto the surface. We investigated the effects of the reaction temperature, macromolecular monomer concentration, UV irradiation time, and photoinitiator concentration on the grafting density (GD) in detail. Furthermore, we investigated the effects of GD under various process conditions on the water uptake and water contact angle. The modified materials had a high water uptake and low water contact angle, which indicated that the hydrophilicity of the PCU surface was improved significantly by the introduction of the hydrophilic poly(ethylene glycol) blocks on the surface. The anticoagulant properties of the material might also have been improved. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

According to the nonlinearity and nonstationarity characteristics of reciprocating compressor vibration signal, a fault feature extraction method of reciprocating compressor based on the empirical wavelet transform (EWT) and state-adaptive morphological filtering (SMF) is proposed. Firstly, an adaptive empirical wavelet transform was used to divide the Fourier spectrum by constructing a scale-space curve, and an appropriate orthogonal wavelet filter bank was constructed to extract the AM-FM component with a tightly-supported Fourier spectrum. Then according to the impact characteristic of the reciprocating compressor vibration signal, the morphological structural elements were constructed with the characteristics of the signal to perform state-adaptive morphological filtering on the partitioned modal functions. Finally, the MF-DFA method of the modal function was quantitatively analyzed and the fault identification was performed. By analyzing the experimental data, it can be shown that the method can effectively identify the fault type of reciprocating compressor valve. [ABSTRACT FROM AUTHOR]

CO gas, as a marker gas in the whole process of coal spontaneous combustion, plays a very important role in the prediction of coal spontaneous combustion. However, a large amount of CO gas can be generated under normal conditions of low-metamorphic coal, which interferes with the prediction of coal spontaneous combustion in low-metamorphic coal seam mining area. Coal samples were collected from five typical mines in Gushan Mine in Pingzhuang, Bulianta Coal Mine in Shendong, Daliuta Coal Mine in Shenmu Mining Area in Shaanxi, Zaoquan Mine in Lingwu Mining Area in Ningxia, and No.1 Mine in Dananhu Mine in Dananhu Mining area in Xinjiang. After oxygen isolation crushing treatment, the CO generation law of coal samples in 5 mining areas during oxygen isolation heating process was studied by using oxygen isolation program heating and Fourier optical interference experiment, and the types of active functional groups on coal molecules with or without oxygen separation heating were analyzed. It was believed that carbonyl (C=O), carboxyl (-COOh), ether (-O-CH3) and other oxygen-containing groups on coal molecules were directly related to the generation of CO gases in low-metamorphism coal at room temperature.

Low-metamorphic coal resources are abundant in China. In mining, the CO concentration exceeds the limit of 0.002 4% in areas such as the return corner of the working face without any signs of spontaneous ignition, which threatens the safe production of the mine. In this paper, five materials of cuprous chloride(CuCl), cuprous bromide(CuBr), silver chloride(AgCl), silver nitrate(AgNO3) and copper chloride(CuCl2) are selected as CO absorbent materials, designed the experiment of CO absorption by CO absorbent, and carried out the experiment of CO absorption by single absorbent solution and multiple absorbent compound solutions. Experimental results show, CuCl, CuBr, AgCl and AgNO3 all have different absorption effects on CO, the single CuCl solution has the best absorption effect, while CuCl2 has no absorption effect on CO; the compound solution containing CuCl and the CuCl single solution have little difference in CO absorption, and the absorption effect is better when the CuCl in the solution is excessive.

Presents numerical simulation and physical characteristics analysis for slender wing rock. Problems caused by wing rock; Development of a full Navier-Stokes methodology to study unsteady vortex-dominated flows about rolling, highly swept delta wings undergoing free-to-roll motions; Results of the analysis.

This paper first analyzes the existing problems of open-pit coal mine from the perspective of industry background, policy guidance, management and control concept, expounds the necessity of establishing intelligent mine, studies the definition, overall framework and construction planning of intelligent construction of open-pit coal mine. According to the 1+ 4 mode, i.e. 1 comprehensive management and control platform, 4 levels(equipment sensing layer, integrated communication network transmission layer, internet platform layer and software application layer), we carry out the construction of intelligent mine, and plan the specific content of the construction by stages, analyze the key technologies in the process of intelligent construction, and discuss the important role and subsystem composition of the intelligent management and control platform of open-pit coal mine.

The effective pressure drop radius of coal reservoir should be enlarged as far as possible to improve the gas production of CBM well. By analyzing the complementary variation law of water production and gas production during the process of CBM well drainage, the multiple coal seam development well group in Guizhou area and the single coal seam development block in Shanxi area are taken as examples to analyze the influence of water production on gas production, and the CBM well extraction measures to increase production efficiency is proposed. The results show that: the CBM wells have changed the gas-water output ratio before and after the casing pressure, and have obvious complementary changes: the CBM wells developed in single coal seam and multiple coal seams all found that the higher the fracturing fluid flow-back rate, the higher the total gas production and average gas production; influenced by the energy and permeability of the formation, the flow-back rate of fracturing fluid in coalbed methane wells has a turning point with the change of burial depth, the transition depth is the appropriate fracture depth for the CBM well in this well area; in order to maximize the effective pressure drop radius of the CBM well, the permeability damage during the drainage process should be minimized, and the blockage of the pores of the pores by the pulverized coal particles should be reduced.

Aiming at the nonlinearity, nonstationarity and multi-component coupling characteristics of reciprocating compressor vibration signals, an integrated feature extraction method based on the variational mode decomposition (VMD) and multi-fractal detrended fluctuation analysis (MFDFA) is proposed for a fault diagnosis for a reciprocating compressor valve. Firstly, to eliminate the noise interference, a novel VMD method with superior anti-interference performance was utilized to obtain several components of the quasi-orthogonal band-limited intrinsic mode function (BLIMF) from a strong non-stationarity vibration signal, and a consistent number K of BLIMFs was selected based on a novel criterion for all fault states. Secondly, the MFDFA method, which can describe the multi-fractal structure feature of non-stationary time series, was applied to analyze each BLIMF component, and the parameters of MFDFA were employed as the eigenvectors to reflect the structure characteristics and local scale behavior of the vibration signal. Then, the principal component analysis (PCA) was introduced to refine the eigenvectors for a higher recognition efficiency and accuracy. Finally, the vibration signals of four types of reciprocating compressor valve faults were analyzed by this method, and the faults were identified correctly by pattern classifiers of BTSVM and CNN. Further results comparison with other feature extraction methods verifies the superiority of the proposed method. [ABSTRACT FROM AUTHOR]