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A steep seam similar simulation system was developed based on the geological conditions of a steep coal seam in the Xintie Coal Mine. Basing on similar simulation, together with theoretical analysis and field measurement, an in-depth study was conducted to characterize the fracture and stability of the roof of steep working face and calculate the width of the region backfilled with gangue in the goaf. The results showed that, as mining progressed, the immediate roof of the steep face fell upon the goaf and backfilled its lower part due to gravity. As a result, the roof in the lower part had higher stability than the roof in the upper part of the working face. The deformation and fracture of main roof mainly occurred in the upper part of the working face; the fractured main roof then formed a “voussoir beam” structure in the strata’s dip direction, which was subjected to the slip- and deformation-induced instability. The stability analysis indicated that, when the dip angle increased, the rock masses had greater capacity to withstand slip-induced instability but smaller capacity to withstand deformation-induced instability. Finally, the field measurement of the forces exerted on the hydraulic supports proved the characteristics of the roof’s behaviors during the mining of a steep seam.

Human transferrin receptor 1 (TfR1) is expressed on malignant cells at levels several fold higher than those on normal cells and its expression can be correlated with tumor stage or cancer progression. It is a potentially rational target for drug delivery. To identify novel ligands which can recognize the TfR1 specifically, a random phage displayed 12-mer peptide library was screened and two consensus motifs of the peptides which are displayed by the positive phages RXR and RXXXR (x is any amino acid) were yield. The phage displaying peptide SPRPRHTLRLSL (designated as B18) exhibited the highest affinity to TfR1 in phage ELISA and B18 could bind to TfR1 specifically in a dose dependent manner. The flow cytometry assay and immunocellularchemistry assay showed that the B18 could bind to TfR1 positive carcinoma cells with specificity. In addition, the biodistribution assay indicated that B18 could home to TfR1 positive tumor tissue specifically. Our study suggests that the peptide exhibited by B18 is a potentially promising targeting peptide for tumor diagnosis and treatment.

AbstractIn this study, the NCEP/NCAR reanalysis dataset was used to analyze the variability modes of the winter upper-level wind field over Asian mid-high latitude region. As shown by the results, the dominant variability modes of the winter upper-level wind field over Asian mid-high latitude region are characterized by the out-of-phase variation in the intensity of the subtropical and temperate jets over East Asia and the meridional shift of the subtropical jet axis, on interannual and multiannual scales, respectively. The first leading variability mode can be used as a good measure to represent the integral variation of atmospheric general circulation in Asian mid- latitude region. Composite analyses suggest that the first leading variability mode of the winter upper-level wind field is intimately related to the atmospheric circulation and temperature anomalies in the northern hemispheric mid-latitude region.

The most serious complication following esophagectomy and conventional intrathoracic · esophagogastrostomy is anastomotic leakage, which contributes to both a high mortality and morbidity postoperatively. The incidence of anastomotic leakage reported in a recent 10 year period ranged from 3% to 18%, with a mean of 4.9%. A series of 433 esophagogastrostomies were performed in our institute from 1954 to 1981 for various esophageal lesions, including 414 cases of carcinoma of the esophagus. A conventional esophagogastrostomy was carried out in 319 patients and 12 leaks occurred postoperatively, an incidence of 3.7%. In comparison, another group of 114 patients underwent “tunnel” esophagogastrostomy, a technique that we designed. There was only one leak, an incidence of 0.87%. The “tunnel” esophagogastrostomy is therefore recommended as a reliable operative procedure for minimizing the incidence of anastomotic leakage. The operative technique is described in detail.

This paper presents an industrial application of multivariable combined self–tuning control techniques to a paper machine. The papermaking process is taken as a MIMO system with unequal time–lag, some time–varying parameters and unstable inverses. In order to design a suitable control scheme for the process, a new control strategy, called multivariable combined self–tuner(MCST), with the U–D factorization recursive algorithm is proposed. The capability of the proposed scheme is demonstrated by its application to the basis weight loop and the moisture loop of the Long Wire Paper Machine(LWPM) at Juxian Paper Mill, Shandong, P.R. China.

Precise measurements of spectra of cosmic ray electrons and positrons can effectively probe the nature of dark matter (DM) particles. In a class of models where DM particles initially annihilate into a pair of intermediate particles which then decay into standard model particles, box-shaped spectra can be generated. Such spectra are distinct from astrophysical backgrounds and can probably be regarded as characteristic features of the DM annihilation. In this work, we search for such a feature in the total electron plus positron spectrum measured by AMS-02 and DAMPE. No significant evidence for such a DM annihilation component has been found. The 95% confidence level upper limits of the velocity-weighted annihilation cross section are derived, which range from ∼10-26 cm³ s-1 for DM mass of 50 GeV to ∼10-23 cm³ s-1 for DM mass of 10 TeV. [ABSTRACT FROM AUTHOR]

The axionlike particle (ALP)-photon mixing in the magnetic field around γ-ray sources or along the line of sight could induce oscillation between photons and ALPs, which then causes irregularities in the γ-ray spectra. In this work we search for such spectral irregularities in the spectrum of PKS 2155-304 using 8.6 years of data from the Fermi Large Area Telescope (Fermi-LAT). No significant evidence for the presence of ALP-photon oscillation is obtained, and the parameter space of ALPs is constrained. The exclusion region sensitively depends on the poorly known magnetic field of the host galaxy cluster of PKS 2155-304. If the magnetic field is as high as ∼10 μG, the "holelike" parameter region allowed in Ref. [1] can be ruled out. [ABSTRACT FROM AUTHOR]

Axionlike particles (ALPs) are one promising type of dark matter candidate particle that may generate detectable effects on γ-ray spectra other than the canonical weakly interacting massive particles. In this work we search for such oscillation effects in the spectra of supernova remnants caused by the photon-ALP conversion, using the Fermi Large Area Telescope data. Three bright supernova remnants, IC443, W44, and W51C, are analyzed. The inclusion of photon-ALP oscillations yields an improved fit to the γ-ray spectrum of IC443, which gives a statistical significance of 4.2σ in favor of such spectral oscillation. However, the best-fit parameters of ALPs (ma=6.6neV, gaγ=13.4×10-11 GeV-1) are in tension with the upper bound (gaγ<6.6×10-11GeV-1) set by the CAST experiment. It is difficult to explain the results using the systematic uncertainties of the flux measurements. We speculate that the "irregularity" displayed in the spectrum of IC443 may be due to the superposition of the emission from different parts of the remnant. [ABSTRACT FROM AUTHOR]