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Traditional matrix does not allow matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) to analyze volatile compounds, because volatile analytes may vaporize during the sample preparation process or in the high vacuum circumstance of ion source. Herein, we reported a Co and N doped porous carbon material (Co-NC) which were synthesized by pyrolysis of a Schiff base coordination compound. Co-NC could simultaneously act as adsorbent of volatile compounds and as matrix of MALDI MS, to provide the capability of MALDI MS to analyze volatile compounds. As adsorbent, Co-NC could strongly adsorb and enrich the volatile compounds in perfume and herbs, and hold them even in the high vacuum circumstance. On the other hand, Co-NC could absorb the energy of the laser, and then transfer the energy to the analyte for desorption and ionization of analyte in both negative and positive ionization modes. Additionally, the background interferences were avoided in the low-mass region (

To position personnel in mines, the study discussed in this paper built on the tunnel personnel positioning method on the basis of both TOA and location-finger print (LFP) positioning. Given non-line of sight (NLOS) time delay in signal transmission caused by facilities and equipment shielding in tunnels and TOA measurement errors in both LFP database data and real-time data, this paper puts forth a database data de-noising algorithm based on distance threshold limitation and modified mean filtering (MMF), as well as a real-time data suppression algorithm based on speed threshold limitation and MMF. On this basis, a nearest neighboring data matching algorithm based on historical location and the speed threshold limitation is used to estimate personnel location and realize accurate personnel positioning. The results from both simulation and the experiment suggest that: compared with the basic LFP positioning method and the method that only suppresses real-time data error, the tunnel personnel positioning methods based on TOA and modified LFP positioning permits effectively eliminating error in TOA measurement, making the measured data close to the true positional data, and dropping the positioning error: the maximal positioning error in measurements from experiment drops by 9 and 3 m, respectively, and the positioning accuracy of 3 m is achievable in the condition used in the experiment. Keywords: Tunnel, Positioning, TOA, Location-finger print (LFP), Modified mean filtering (MMF), Distance threshold, Speed threshold

Protein tyrosine phosphatase, nonreceptor type 13 (PTPN13), has emerged as a critical cancer-related gene that is implicated in a wide range of cancer types. However, the role of PTPN13 in clear cell renal cell carcinoma (ccRCC) is poorly understood. In the present study, we aimed to evaluate whether PTPN13 participates in the progression of ccRCC. Decreased expression of PTPN13 was found in ccRCC tissues, which predicted a shorter survival rate in ccRCC patients. PTPN13 expression was also lower in ccRCC cell lines, and the upregulation of PTPN13 repressed the proliferation, colony formation and invasion, but enhanced the apoptosis of ccRCC cells. In contrast, the silencing of PTPN13 produced the opposite effects. Further data showed that PTPN13 overexpression decreased the phosphorylation of Akt, while PTPN13 silencing increased the phosphorylation of Akt. Treatment with Akt inhibitor markedly abrogated the PTPN13 silencing-evoked oncogenic effect in ccRCC cells. Xenograft tumor experiments revealed that overexpression of PTPN13 remarkably restricted the tumor formation and growth of ccRCC cells in vivo associated with inactivation of Akt. In conclusion, our data demonstrated that overexpression of PTPN13 restricts the proliferation and invasion of ccRCC cells through inactivation of Akt. Our study suggests a tumor suppressive function of PTPN13 in ccRCC and highlights the potential role of PTPN13 in the progression of ccRCC.

Spinal cord injury (SCI) is one of the most disabling diseases. Cell-based gene therapy is becoming a major focus for the treatment of SCI. Bone marrow-derived mesenchymal stem cells (BMSCs) are a promising stem cell type useful for repairing SCI. However, the effects of BMSCs transplants are likely limited because of low transplant survival after SCI. Sonic hedgehog (Shh) is a multifunctional growth factor which can facilitate neuronal and BMSCs survival, promote axonal growth, prevent activation of the astrocyte lineage, and enhance the delivery of neurotrophic factors in BMSCs. However, treatment of SCI with Shh alone also has limited effects on recovery, because the protein is cleared quickly. In this study, we investigated the use of BMSCs overexpressing the Shh transgene (Shh-BMSCs) in the treatment of rats with SCI, which could stably secrete Shh and thereby enhance the effects of BMSCs, in an attempt to combine the advantages of Shh and BMSCs and so to promote functional recovery. After Shh-BMSCs treatment of SCI via the subarachnoid, we detected significantly greater damage recovery compared with that seen in rats treated with phosphate-buffered saline (PBS) and BMSCs. Use of Shh-BMSCs increased the expression and secretion of Shh, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), improved the behavioral function, enhanced the BMSCs survival, promoted the expression level of neurofilament 200 (NF200), and reduced the expression of glial fibrillary acidic protein (GFAP). Thus, our results indicated that Shh-BMSCs enhanced recovery of neurological function after SCI in rats and could be a potential valuable therapeutic intervention for SCI in humans.

Based on the stability and inequality of texture features between coal and rock, this study used the digital image analysis technique to propose a coal–rock interface detection method. By using gray level co-occurrence matrix, twenty-two texture features were extracted from the images of coal and rock. Data dimension of the feature space reduced to four by feature selection, which was according to a separability criterion based on inter-class mean difference and within-class scatter. The experimental results show that the optimized features were effective in improving the separability of the samples and reducing the time complexity of the algorithm. In the optimized low-dimensional feature space, the coal–rock classifier was set up using the fisher discriminant method. Using the 10-fold cross-validation technique, the performance of the classifier was evaluated, and an average recognition rate of 94.12% was obtained. The results of comparative experiments show that the identification performance of the proposed method was superior to the texture description method based on gray histogram and gradient histogram. Keywords: Coal–rock interface detection, Texture, Gray level co-occurrence matrix, Feature selection, Fisher discriminant method, Cross-validation

Since the coal mine in-pit personnel positioning system neither can effectively achieve the function to detect the uniqueness of in-pit coal-mine personnel nor can identify and eliminate violations in attendance management such as multiple cards for one person, and swiping one’s cards by others in China at present. Therefore, the research introduces a uniqueness detection system and method for in-pit coal-mine personnel integrated into the in-pit coal mine personnel positioning system, establishing a system mode based on face recognition + recognition of personnel positioning card + release by automatic detection. Aiming at the facts that the in-pit personnel are wearing helmets and faces are prone to be stained during the face recognition, the study proposes the ideas that pre-process face images using the 2D-wavelet-transformation-based Mallat algorithm and extracts three face features: miner light, eyes and mouths, using the generalized symmetry transformation-based algorithm. This research carried out test with 40 clean face images with no helmets and 40 lightly-stained face images, and then compared with results with the one using the face feature extraction method based on grey-scale transformation and edge detection. The results show that the method described in the paper can detect accurately face features in the above-mentioned two cases, and the accuracy to detect face features is 97.5% in the case of wearing helmets and lightly-stained faces. Keywords: Coal mine, Uniqueness detection, Recognition of personnel positioning cards, Face recognition, Generalized symmetry transformation

The attenuation characteristics of electromagnetic waves propagation in an arched tunnel cannot be studied by means of the classical theory method. Based on the equivalent analysis method, the lowermost attenuation mode of the arched tunnel was analysed and compared with attenuation modes of the circular tunnel with the equal cross sectional area. The results show that it is feasible to compare the lowermost attenuation mode of the arched tunnel with that of the circular tunnel. The influence of the relative permittivity of tunnel walls is significant. The different equivalent modes are adopted according to different relative permittivity values.