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In this paper, smoothed bond-based peridynamics (SBBPD) is proposed to simulate the large deformation. The governing equation of smoothed bond-based PD is obtained by incorporating the observed changes in the density field and long-range force reaction in Eulerian form. The Hencky stretch is introduced into smoothed bond-based PD to calculate the true strain because of the change in density (volume). The proposed method can achieve a more accurate result in solid mechanics compared with SPH and can well handle extremely large deformation problems compared with traditional bond-based PD. Numerical experiments are launched to test these modifies of smoothed bond-based PD method in solid mechanics.

Understanding the mechanical properties plays pivotal roles in rock engineering. This work aims to establish novel relations linking the porosity, ultrasonic wave and fluid saturation to estimate the uniaxial compressive strength (UCS) fast and simply. The uniaxial compressive coupled with ultrasonic wave tests on sandstone samples are carried out to obtain the datasets of the UCS, P-wave and S-wave velocities. X-ray CT imaging technique is employed to capture the microstructure information. The color difference phase separation approach to segment the pore, water and solid phases is proposed, and pore-scale variables to describe the microstructure characteristics are defined. Novel relations to determine the micro velocities of P-wave and S-wave are established, and the modulus of deformation and the physical properties of rocks are evaluated. Novel relation to determine the UCS is established and validated by the real and virtual experiment datasets. Results show that the UCS, P-wave and S-wave velocities computed by the proposed method decrease with increasing fluid saturation. The errors between the calculated and experimental UCS, P-wave and S-wave velocities are all

This paper details a method for investigating the stability of a layered slope that combines random field theory with horizontal integration. Both the cohesion and friction coefficient are treated as a Gaussian random field. The closed-form solution of the factor of safety and the probability of failure of the layered slope are derived, in which the effects of spatial correlation lengths and spatial correlation parameters on the stability of the layered slope are considered. The derived probability of failure is greatly affected by the input spatial correlation length of the soil parameters. The effectiveness of this proposed method is validated with the results of the Monte Carlo simulation.

The distinction of hepatocellular carcinoma (HCC), neuroendocrine tumor (NET) metastatic to the liver, and cholangiocarcinoma (CC) can sometimes be challenging on small biopsies. Tissue microarrays were constructed from HCCs, NETs, and CCs. The immunoprofile was evaluated using HepPar1, glypican-3 (GPC3), synaptophysin (SYN), chromogranin A (CHR), CD56, MOC-31, and pCEA. One hundred thirteen HCCs, 48 NETs, and 44 CCs were included. Of HCCs, 107 (95 %) expressed HepPar1 and/or GPC3, 52 (46 %) both, and 97 (88 %) marked with pCEA (canalicular pattern). Seven (6 %) expressed CD56, of which 3 (3 %) expressed SYN. All 7 HCCs that expressed CD56 and/or SYN also expressed HepPar1 and/or GPC3, and none of the HCCs expressed CHR. Fourteen (13 %) expressed MOC-31. All 48 NETs expressed at least one neuroendocrine marker: 47 (98 %) positive for SYN, 40 (83 %) for CHR, 39 (81 %) for CD56, and 34 (71 %) for all three markers. None expressed HepPar1 or GPC3. All 44 CCs showed at least focal reactivity with MOC-31 and pCEA (membranous/cytoplasmic). One (2 %) was positive for HepPar1, 4 (9 %) for GPC3, 1 (2 %) for SYN and CHR, and 7 (16 %) for CD56. HCCs rarely express CD56 and SYN, while all express either HepPar1 or GPC3. NETs do not express HepPar1 or GPC3 and almost always express SYN, while CHR and CD56 are seen in most cases. Rare CCs focally express HepPar1 and GPC3. Utilizing a limited staining panel can efficiently distinguish HCCs, NETs, and CCs and help avoid diagnostic pitfalls on small biopsies.

A design matrix in response surface method (RSM) that satisfies the orthogonality is very useful because the mean square error can be minimized, so that the response surface is more precise. But the orthogonality of a second-order design matrix in conventional RSM cannot be satisfied. In this paper, a second-order orthogonal experimental design (SOED)-based RSM is proposed by considering the orthogonality of high-order design matrix. The SOED is constructed by changing the length of star points, and the main characteristic of SOED is that the design matrix is diagonal. When the high-order terms are considered in the SOED-based RSM, a globe optimal solution can be found. As the regression equation is determined, the reliability index can be analyzed by the normalized distance between the mean value of the performance function and the critical limit state of the safety factor. A practical large-scale landslide with two slip surfaces is taken to verify the applicability and precision of the proposed method in detail. It is found that the SOED-based response surface is more rigorous than the conventional RSM.

Increased autophagic vacuoles (AVs) occur in injured or degenerating neurons, under both developmental and pathological situations. Although an induced autophagy has been shown in inflammation response to cell factors, the underlying mechanism(s) remain(s) unknown. Here, we show that both cell factor IL-6 and environmental toxin MPP(+) promote the formation of vacuolation in SHSY5Y cells. By electron and immunofluorescent microscopy analyses, we showed that these structures are acid autolysosomes, containing cellular debris, and labeled by LC3 or LAMP1, markers of autophagosomes or lysosomes, respectively. Combining MPP(+) and IL-6 do not further increase vacuolation of SHSY5Y cells, and the vacuolation is less than that in the MPP(+)-treated group. MPP(+)-induced vacuolation results from significant increase in autophagy formation and delay in autophagy degradation, in relation to a decline of the lysosomal activity of arylsulfatase A. At molecular level, we show that this defect in autolysosomal maturation is independent of mammalian target of rapamycin and p38 inhibitions. Most importantly, we provide the first evidence that activation of ERK pathway is sufficient to commit cell to autophagic vacuolation. The sustained activation is required for MPP(+) to disrupt the autophagic pathway. IL-6 also induces a temporary and significant activation of ERK, but not sustained activation, and change sustained activation in MPP(+)-treated group into temporary activation. Taken together, these findings strongly support that IL-6 promotes the maturation of autophagosomes into functional autolysosomes by regulating ERK.

Background Fusion proteins have unique oncogenic properties and their identification can be useful either as diagnostic or therapeutic targets. Next generation sequencing data have previously shown a fusion gene formed between Rad51C and ATXN7 genes in the MCF7 breast cancer cell line. However, the existence of this fusion gene in colorectal patient tumor tissues is largely still unknown. Methods We evaluated for the presence of Rad51C-ATXN7 fusion gene in colorectal tumors and cells by RT-PCR, PCR, Topo TA cloning, Real time PCR, immunoprecipitation and immunoblotting techniques. Results We identified two forms of fusion mRNAs between Rad51C and ATXN7 in the colorectal tumors, including a Variant 1 (fusion transcript between Rad51C exons 1–7 and ATXN7 exons 6–13), and a Variant 2 (between Rad51C exons 1–6 and ATXN7 exons 6–13). In silico analysis showed that the Variant 1 produces a truncated protein, whereas the Variant 2 was predicted to produce a fusion protein with molecular weight of 110 KDa. Immunoprecipitation and Western blot analysis further showed a 110 KDa protein in colorectal tumors. 5-Azacytidine treatment of LS-174 T cells caused a 3.51-fold increase in expression of the fusion gene (Variant 2) as compared to no treatment controls evaluated by real time PCR. Conclusion In conclusion we found a fusion gene between DNA repair gene Rad51C and neuro-cerebral ataxia Ataxin-7 gene in colorectal tumors. The in-frame fusion transcript of Variant 2 results in a fusion protein with molecular weight of 110 KDa. In addition, we found that expression of fusion gene is associated with functional impairment of Fanconi Anemia (FA) DNA repair pathway in colorectal tumors. The expression of Rad51C-ATXN7 in tumors warrants further investigation, as it suggests the potential of the fusion gene in treatment and predictive value in colorectal cancers. Electronic supplementary material The online version of this article (doi:10.1186/s12943-016-0527-1) contains supplementary material, which is available to authorized users.

Described in this paper are the synthesis, characterization and catalytic application of H-ZSM-5 zeolites for the conversion of CH3Br into aromatics. The H-ZSM-5 zeolites were fabricated by hydrothermal crystallization using n-butylamine (BTA) as a template and characterized by XRD, SEM and NH3-TPD techniques. The effects of batch SiO2/Al2O3 ratio, alkalinity, NaCl/Al2O3 ratio, seed crystals, and crystallization time on the yield, structure/texture and catalytic performance were systematically studied. Adopting the optimum sol (SiO2/Al2O3 = 70, BTA/SiO2 = 0.2847, Na2O/SiO2 = 0.1237, H2O/SiO2 = 37.4, NaCl/Al2O3 = 60, and seed/SiO2 = 5 wt%) and under the most preferable crystallization conditions of 100 °C/24 h–170 °C/24 h, H-ZSM-5 zeolites of high crystallinity and small size (300–700 nm) were obtained. Good catalytic performance was observed over the H-ZSM-5 zeolites (aromatic yield up to 44.2%). However, unlike the modification of large commercial HZSM-5, the use of MoO3 or PbO as modifying agents for the small-size H-ZSM-5 zeolites results in a decline of catalytic performance. The relationship between the structure and the catalytic efficiency of as-synthesized H-ZSM-5 samples were investigated. It was found that with crystallinity enhancement and/or decline in crystal size, there is improvement of catalytic performance.

Objective To observe the effect of acupuncture plus LONG’s manual manipulations on the functional improvement of the patients with lumbar intervertebral disc protrusion.

A new reaction system was designed to economically convert glucose to lactic acid environment-friendly. Hydrophobic ionic liquids were chosen as solvent that can promote the decomposition reaction of glucose, and the catalytic performance of the solid bases was evaluated. Both the reaction temperature and time can affect the yield of lactic acid. A high yield (97%) of lactic acid was achieved under the optimal reaction condition. The 1H NMR spectra and HPLC-MS were used to identify the formation of the lactic acid and variations of ionic liquid. It is found that ionic-liquids have a unique solvent effect for glucose and bases. Water can be used as solvent to extract calcium lactate. This shows a great potential of hydrophobic ionic liquids in the solid bases catalyzed reaction that is limited by the weak solubility of solid bases in organic and water solution.

Methyl bromide was synthesized by reacting methane with oxygen and hydrogen bromide over Rh/SiO2 catalyst. The reaction started from the oxidation of HBr to form active bromine species (Br• radicals and Br* surface species), which in turn reacted with CH4 to form CH 3 • radicals and $$\hbox{CH}_{3}^{\ast}$$ surface species. These CH 3 • and $$\hbox{CH}_{3}^{\ast}$$ species reacted with the active bromine species to form CH3Br and CH2Br2. The presence of HBr inhibited the deep oxidation and the steam reformation of CH4 and therefore, guaranteed the high selectivity of CH3Br. In the presence of HBr, CO was formed from the oxidation and steam reformation of CH3Br, while CO2 was formed from the oxidation and steam reformation of CO over Rh/SiO2 at reaction temperature higher than 560 °C.

Alkanes such as iso-butane, n-pentane, and cyclohexane have been converted effectively to maleic anhydride, 2-methyl maleic anhydride, and acetic acid over MoVO catalysts below 330 °C. In order to explore the possible reaction pathways, the oxidation of iso-butene, cyclohexene, 2-methyl-1-propanol, tert-butanol, and 2-methylacrylic acid were examined over the catalysts. In iso-butene oxidation, acetic acid and 2-methyl maleic anhydride were detected but not maleic anhydride. In cyclohexene oxidation, benzene and phenol were detected as major products but it was not the case in cyclohexane oxidation. The results of our investigation indicate that the oxidation pathway of iso-butane is different from that of iso-butene, 2-methyl-1-propanol, tert-butanol, and 2-methylacrylic acid, whereas the oxidation pathway of cyclohexane is different from that of cyclohexene.

Methyl 3,3-dimethoxypropionate was prepared via the oxidation of acrylic acid by oxygen in methanol over PdCl2/CuCl2 catalyst. An acrylic acid conversion of 95.2% with a methyl 3,3-dimethoxypropionate selectivity of 90.6% was obtained at 35 °C and 5 atm. The reaction pathway might be that the esterification of acrylic acid in methanol was the first step, then methyl acrylate reacted with oxygen to form an intermediate aldehyde, which could react with methanol to form methyl 3,3-dimethoxypropionate.

Dimethyl ether is a potential clean fuel and intermediate for other chemical synthesis, such as gasoline, ethylene, and acetic acid. To synthesize dimethyl ether from the traditional syngas process is an energy consuming process. More than one fourth of natural gas must be burned to generate heat for the steam reformation of natural gas. Here, we show a non-syngas process to synthesize dimethyl ether. This process consists of the conversion of methane to bromomethane by reacting methane with hydrogen bromide and oxygen and the hydrolysis of bromomethane to dimethyl ether. Through this process, methane can be high efficiently converted to dimethyl ether.

We have recently shown that analysis of BAT-26, was sufficient to establish the Replication Error status of colorectal tumors and cell lines without the need for matching normal DNA. BAT-26, a poly(A) tract in the 5th intron of the hMSH2 gene, does not present significant size variation either between the alleles of one individual or between alleles of different individuals. In colorectal tumors without defects in the replication error system (RER- phenotype), BAT-26 is also quasi-monomorphic. On the contrary, in RER+ colorectal tumors, BAT-26 shows unstable shortened alleles. In order to see whether this behaviour was specific for BAT-26, or was a more general phenomenon for mononucleotide repeat microsatellites, we analysed eight other mononucleotide repeats. In control individuals (72 samples) and in RER- colorectal tumors and cell lines (55 samples), these microsatellites were polymorphic, dimorphic, quasi-monomorphic or monomorphic, indicating that the quasi-monomorphic nature of BAT-26 was not a general rule. All of them showed a tendency to be shorter in RER+ colorectal tumors and cell lines (19 samples), but only quasi-monomorphic and monomorphic mononucleotide repeats could be used to determine the RER status of tumors without matching normal DNA, although with a lower efficiency than BAT-26 due to either a smaller range of shortening in RER+ tumors or to a larger number of false negative cases.