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Nasopharyngeal carcinoma (NPC) is an epithelia-derived malignancy with a distinctive geographic distribution. Cystathionine γ-lyase (CSE) is involved in cancer development and progression. Nevertheless, the role of CSE in the growth of NPC is unknown. In this study, we found that CSE levels in human NPC cells were higher than those in normal nasopharyngeal cells. CSE overexpression enhanced the proliferative, migrative, and invasive abilities of NPC cells and CSE downregulation exerted reverse effects. Overexpression of CSE decreased the expressions of cytochrome C, cleaved caspase (cas)-3, cleaved cas-9, and cleaved poly-ADP-ribose polymerase, whereas CSE knockdown exhibited reverse effects. CSE overexpression decreased reactive oxygen species (ROS) levels and the expressions of phospho (p)-extracellular signal-regulated protein kinase 1/2, p-c-Jun N-terminal kinase, and p-p38, but promoted the expressions of p-phosphatidylinositol 3-kinase (PI3K), p-AKT, and p-mammalian target of rapamycin (mTOR), whereas CSE knockdown showed oppose effects. In addition, CSE overexpression promoted NPC xenograft tumor growth and CSE knockdown decreased tumor growth by modulating proliferation, angiogenesis, cell cycle, and apoptosis. Furthermore, DL-propargylglycine (an inhibitor of CSE) dose-dependently inhibited NPC cell growth via ROS-mediated mitogen-activated protein kinase (MAPK) and PI3K/AKT/mTOR pathways without significant toxicity. In conclusion, CSE could regulate the growth of NPC cells through ROS-mediated MAPK and PI3K/AKT/mTOR cascades. CSE might be a novel tumor marker for the diagnosis and prognosis of NPC. Novel donors/drugs that inhibit the expression/activity of CSE can be developed in the treatment of NPC.

Mutations in GJA8 are associated with hereditary autosomal dominant and recessive cataract formation. In this study, a novel insert mutation in GJA8 was identified in a Chinese congenital cataract family and cosegregated with the disease in this pedigree. This insert mutation introduces five additional amino acid residues YAVHY after histidine at the 95 site (p.H95_A96insYAVHY) within the second transmembrane (TM2) domain of Cx50 protein (Cx50-insert). Ectopic expression of Cx50-insert protein impairs the hemichannel functions and gap junction activity compared to wild-type Cx50 protein in human lens epithelial cells. Cx50-insert proteins were mislocated from cytoplasmic membrane to endoplasmic reticulum and lysosome. In mouse lens tissue, our results showed that Cx50 predominant expresses in epithelial cells and fiber cells at the transition zone of lens hinting its roles in lens differentiation. Taken together, these data suggest that the novel insert mutation in the TM2 domain of Cx50 protein, which impairs its trafficking to the cell membrane and gap-junction function, is associated with the cataract formation in this Chinese pedigree.

s Nanosized particles of Bi0.95Y0.05Fe0.97M0.03O3 (M ​= ​Mn,Co,Ni,Cu,Zn) were successfully synthesized through thermal decomposition coordination precursors with diethylenetriaminepentaacetic acid (H5dtpa) as ligand. All prepared samples were characterized by XRD, Uv–vis DRS, SEM, PL, EIS, VSM and so on. From XRD results, the main phase of the samples was rhombohedral R3c (161) BiFeO3, and contained a small amount of soft iron ore Bi25FeO40. The phase and morphology of prepared samples were affected by doping ions. The average grain size of the samples was about 20 ​nm.T.The Uv–vis demonstrated the band gap of all samples was less than 2 ​eV and the response to light of all samples extended from ultraviolet region to visible region (~650 ​nm).The BFO–Y–Mn exhibited the minimum band gap of 1.77 ​eV. At the same time, photocatalytic activities of all samples prepared were evaluated through the photocatalytic degradation of methyl orange (MO). BiFeO3 co-doping with 5%Y3+ and 3%Mn2+ exhibited excellent photocatalytic activity for MO solution. In the present of BFO–Y–Mn, the degradation rate of MO under light irradiation of 3 ​h was about 98%.

Uniform-large-sized F-substituted hydroxyapatite (FHAp) crystals with controllable morphologies were successfully synthesized via hydrothermal treatment by using double-facile surfactants. The products were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy. It was found that the size and morphology of FHAp crystals were drastically influenced by pH, precursor concentration and F− content. The growth process was investigated by following time-dependent experiments. The possible growth process was also discussed. Keywords: F-substituted hydroxyapatite, Surfactant, Hydrothermal

This article addresses the high-precision coordinated control problem of spacecraft autonomous rendezvous and docking, which couple the relative position and attitude in the final approach phase. The coupled dynamics equations of the tracking-target spacecrafts is derived by using dual quaternions. Then, a cascade Active Disturbance Rejection Controller is proposed, by which the extended state observer and nonlinear error feedback law is designed, the virtual value on which the actual control volume tracking is calculated to ensure the finite time convergence of the relative position and attitude tracking errors in spite of parametric uncertainties and external disturbances. Finally, numerical simulations are performed to demonstrate that the proposed approaches, which can avoid the coupling effect and restrain the interference, can track the target spacecraft in a relatively short period of time, and the control precision can satisfy the requirements of docking.

Y3+ doped Bi2O3 photocatalysts with enhanced photocatalytic activity were synthesized via thermal decomposition of molecular precursor at 500 °C and characterized by X-ray powder diffraction (XRD), Brunauer–Emmett–Teller surface area, field emission scanning electron microscopy (FE-SEM), energy dispersive analysis of X-rays (EDX), ultraviolet–visible diffuse reflectance spectroscopy (UV–vis DRS), and photoluminescence spectra (PL). The XRD results indicated that the introduction of Y3+ ions can stabilize the phase of Bi2O3. The DRS results indicated that the doping of Y3+ increased the visible light absorption ability of Bi2O3 and red-shifts appeared when compared with pure Bi2O3. Their photocatalytic activities were evaluated through the photocatalytic degradation of methyl orange. The results showed that an appropriate concentration of yttrium dopant can enhance the photocatalytic performance of Bi2O3 due to the strong visible light absorption and the efficient inhibition of the recombination of photogenerated electron–hole pairs. The active species trapping experiments indicated · O 2 − is the main active species in the photocatalytic reaction. Recycling experiments demonstrated that Y-doped Bi2O3 has strong photostability and recyclability and it will be a promising photocatalyst for the photodegradation of organic dyes in water.

Hydroxyapatite (HA) microspheres were successfully synthesized under hydrothermal conditions in the presence of ethylene diamine tetraacetic acid disodium salt (Na 2 EDTA). The morphology and structure of the as-synthesized microspheres were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy analyses. The morphology of HA was significantly affected by pH, Na 2 EDTA/Ca ratio, and reaction temperature. High pH values could promote the formation of microspheres. The structures were transformed from tight to estrange with decreasing pH. The Na 2 EDTA/Ca ratio affected self-assembled, the ratio of Na 2 EDTA/Ca at 2:2 resulted in the formation of a dense spherical structure. The reaction temperature affected the degree of the density of the microspheres. HA microspheres with high crystallinity can be produced under conditions with high pH, high temperature, and moderate holding time. The mechanism underlying the formation of HA microspheres in the presence of Na 2 EDTA at high pH was proposed. At the initial stage of the reaction, crystals were formed and the trunk appeared with a rod-like HA self-assembly. With prolonged reaction time, dumbbell-like HA was formed. Further growth could produce HA microspheres.

Carbonated hydroxyapatite (CHAp) powders with controllable morphologies and sizes were successfully synthesized via hydrothermal treatment by using hexamethylenetetramine (HMT) as a hydroxide anion-generating agent in a phosphate-surplus precursor solution. The products were characterized by X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and selected-area electron diffraction. The results revealed that the morphologies (such as microrods, sheet-like-assembled flowers, shaft wheel-like structures, bur-like spheres, dumbbell-shaped structures, and microspheres) of the products could be well tailored by regulating the reaction acidity and time. A possible growth mechanism accompanied by the effects of HMT on crystal nucleation and growth was preliminarily proposed for the formation of the controllable structures. This work indicated that the use of HMT as a hydroxide anion-adjusting agent is an effective strategy to finely control the morphology of CHAp crystals.

The effects of aging, crystallization temperature and time, and structure directing agent (SDA) on the synthesis of T-type zeolite nanoparticles were investigated systematically. The synthesized zeolites were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and BET measurements. Under optimal synthesis conditions, pure T-type zeolites with a particle size of 150–200 nm were successfully prepared in a time period as short as 120 h. The equilibrium adsorption of pure gases CO 2 , N 2 , and CH 4 on the synthesized T-type zeolite nanoparticles were measured at 288, 298 and 313 K. The T-type zeolite nanoparticles showed the capability of selective adsorption of CO 2 over N 2 and CH 4 . At 288 K and 100 kPa, the selectivity of CO 2 /N 2 and CO 2 /CH 4 of the T-type zeolite nanoparticles was 53.71 and 19.15 respectively. Compared to the micro-level T-type zeolite particles, the T-type zeolite nanoparticles exhibited a higher CO 2 adsorption capacity. At 288 K and 100 kPa, the T-type zeolite nanoparticles showed 4.01 mmol/g CO 2 adsorption capacities, 30% higher than micro-level T-type zeolite. The dynamic adsorption experiments of CO 2 /N 2 and CO 2 /CH 4 binary gas mixtures demonstrated that the synthesized T-type zeolite nanoparticles have promising adsorption capability and recyclability for the separation of CO 2 /N 2 and CO 2 /CH 4 in the potential application to post-combustion CO 2 separation or natural gas purification process.

s Flowback water from shale gas well drilling has a high TDS (total dissolved solids) content, ranging from 5000 ppm to 261,000 ppm, along with a TSS (total suspended solids) content of 300–3000 mg/L. Recently, the rapid expansion of shale gas production in Marcellus Formation has raised serious environmental concerns about the large amount of flowback water in this area. A process based on ceramic membrane filtration and ion-exchange was studied for the treatment of the flowback water from Marcellus Formation. The studied process contains a combination of two MF (microfiltration) membranes, 1.4 μm and 0.2 μm respectively, and mixed bed ion-exchange. After treatment, all TSS and >99% of TDS were successfully removed from the flowback water to meet the criteria for surface discharge. The cost estimation of the treatment is approximately 18.4 $/m 3 , 40–70% lower than the cost estimate of the DEP(Department of Environmental Protection in Pennsylvania).

A new heterometallic antimony–samarium complex, [Sb2(edta)2Sm(H2O)4]NO3 · 3.55H2O (edta = ethylenediaminetetraacetate) (1), has been synthesized and characterized by elemental analyses (EA), Fourier transform infrared spectroscopy, thermogravimetry-differential scanning calorimetry, and X-ray crystallography. The X-ray crystal structure analysis reveals that in 1 the bridging carboxylate-O,O′ of edta4− connects samarium(III) and antimony(III) to form 2-D sheets. The 2-D sheets are further linked by bridging carboxylates from adjacent layers, resulting in 3-D coordination polymers. Complex 1 exhibits fluorescence in the solid state at room temperature.

A new ethylenediamine-N,N,N′,N′-tetraacetate (edta)-linked heterometallic holmium–antimony compound 1 with the formula [Sb2(edta)2Ho(H2O)4]NO3·3.6H2O has been synthesized and characterized by elemental analyses (EA), X-ray crystallography, X-ray powder diffraction patterns (PXRDs), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analyses (TGA). X-ray crystal structure analysis reveals that the bridging carboxylate-O, O′ groups of edta, connect with Ho(III) and Sb(III) ions to form a 2D heterometallic network in compound 1. The 2D networks are further linked by bridging the carboxylate groups from the adjacent layers, resulting in the 3D coordination polymer. The thermal stability and the thermal decomposition process of this crystalline material have also been investigated by TGA–DSC. In addition, the magnetic properties of compound 1 have been studied.

Samnium(III)-bismuth(III) heterobimetallic complexes, SmBi(edta)(NO3)2·7H2O (1) and SmBi(dtpa)(NO3)·3.5H2O(2) (edta=ethylenediaminetetraacetate, dtpa=diethylenetriaminepentaacetate), were synthesized and characterized by means of X-ray single crystal diffraction, X-ray powder diffraction, elemental analysis, ICP, FT-IR spectra and thermal analysis. The structure analysis revealed that 1 is in crystalline and 2 is in non-crystal state. Complex 1 crystallizes in monoclinic, space group P2(1)/n with a=1.2622(2) nm, b=0.81157(15) nm, c=2.3634(5) nm, β=105.340(2)°, V=2.3347(8) nm3, Z=4, Dc=2.563 g·cm−3, µ=10.125 mm−1. Bridging edta4− anions between Bi(III) atoms and Sm(III) atoms result into infinite 3D network structure. Thermal decomposition of the two complexes proceeds in similar stages, i.e., dehydration, pyrolysis of ligand, and decomposition of salt, and the final residue is oxide. In addition, the spectral properties have been studied through FL spectra and UV-Vis DRS. The two complexes exhibit one broad band Bi 6s6p-6s2 emission under UV excitation and the characteristic Sm3+ ion 4G5/26HJ/2 (J=5, 7, 9, 11) transitions under visible light excitation, respectively.

The CO2 reforming reaction on Ba0.5Sr0.5Co0.8Fe0.2Ox (BSCF) oxygen permeable membranes was investigated at 800 °C over a Pt/ZrO2 and a Pt/CeZrO2 (17.5 wt% Ce) catalyst. To determine the effect of oxygen flux on the reaction, both dense and asymmetric BCSF membranes were tested. The results showed that the oxygen permeable membrane effectively increased the activity of the catalyst and the conversion of CH4. Furthermore, the asymmetric membrane had higher oxygen flux compared to the dense BCSF membrane. A mechanism involving steam reforming due to the high oxygen flux and formation of water is proposed which is enhanced by the synergistic relationship between the catalyst and the membrane. The BSCF membranes were found to maintain mechanical stability during the reaction. However, a decrease in CH4 conversion as a function of time was observed for both the Pt/ZrO2 and Pt/CeZrO2 catalysts. This decrease is ascribed to a decrease in the oxygen flux caused by carbonate formation on the surface of the permeate side of the membrane.