Multi-scale simulation of capillary pores and gel pores in Portland cement paste

The microstructures of Portland cement paste (water to cement ratio is 0.4, curing time is from 1 day to 28 days) are simulated based on the numerical cement hydration model, HUMOSTRUC3D (van Breugel, 1991; Koenders, 1997; Ye, 2003). The nanostructures of inner and outer C-S-H are simulated by the packing of monosized (5 nm) spheres. The pore structures (capillary pores and gel pores) of Portland cement paste are established by upgrading the simulated nanostructures of C-S-H to the simulated microstructures of Portland cement paste. The pore size distribution of Portland cement paste is simulated by using the image segmentation method (Shapiro and Stockman, 2001) to analyse the simulated pore structures of Portland cement paste. The simulation results indicate that the pore size distribution of the simulated capillary pores of Portland cement paste at the age of 1 day to 28 days is in a good agreement with the pore size distribution determined by scanning electron microscopy (SEM). The pore size distribution of the simulated gel pores of Portland cement paste (interlayer gel pores of outer C-S-H and gel pores of inner C-S-H are not included) is validated by the pore size distribution obtained by mercury intrusion porosimetry (MIP). The pores with pore size of 20 nm to 100 nm occupy very small volume fraction in the simulated Portland cement paste at each curing time (0.69% to 1.38%). This is consistent with the experimental results obtained by nuclear magnetic resonance (NMR)

[N,N′-Bis(3-meth­oxy-2-oxidobenzyl­idene)ethyl­enediammonium-κ4 O,O′,O′′,O′′′]tris­(nitrato-κ2 O,O′)dysprosium(III)

In the title mononuclear Schiff base complex, [Dy(NO3)3(C18H20N2O4)], the DyIII ion is ten-coordinated in a distorted hexa­deca­hedral geometry by six O atoms of three nitrate anions and four O atoms of the Schiff base ligand. An intra­molecular N—H⋯O hydrogen bond occurs. The crystal structure is stabilized by inter­molecular C—H⋯O hydrogen bonds

{μ-6,6′-Dimeth­oxy-2,2′-[propane-1,3-diylbis(nitrilo­methyl­idyne)]diphenolato}trinitratocopper(II)europium(III)

In the title complex, [CuEu(C19H20N2O4)(NO3)3], the CuII ion is four-coordinated in a square-planar geometry by two O atoms and two N atoms of the deprotonated Schiff base. The EuIII atom is ten-coordinate, chelated by three nitrate groups and linked to the four O atoms of the deprotonated Schiff base

{μ-6,6′-Dimeth­oxy-2,2′-[propane-1,3-diyl­bis(nitrilo­methyl­idyne)]­diphenolato}­trinitratocopper(II)samarium(III) acetone solvate

In the title complex, [CuSm(C19H20N2O4)(NO3)3]·CH3CO-CH3, the CuII atom is four-coordinated in a square-planar geometry by two O atoms and two N atoms of the deprotonated Schiff base. The SmIII atom is ten-coordinate, chelated by three nitrate groups and linked to the four O atoms of the deprotonated Schiff base

Constraints on Axion-like Particles from Observations of Mrk 421 using the CLs{\rm CL_s} Method

Axion-like particles (ALPs) could mix with photons in the presence of astrophysical magnetic fields, and result in oscillations in the high energy $\gamma$-ray spectra observed by experiments. In this work, we investigate the ALP-photon oscillation effect through the blazar Mrk 421 spectra of 15 periods observed by Major Atmospheric Gamma Imaging Cherenkov Telescopes (MAGIC) and Fermi Large Area Telescope (Fermi-LAT). Compared with previous studies, we generate the mock data under the ALP hypothesis and apply the ${\rm CL_s}$ method to set constraints on the ALP parameters. This method is widely employed in high energy experiments and could avoid the possibility of excluding some parameter regions due to the fluctuation. We find that the ALP-photon coupling $g_{a\gamma}$ is constrained to be smaller than $\sim 2\times10^{-11}$ GeV$^{-1}$ for ALP mass ranging from $10^{-9}$ eV to $10^{-7}$ eV at a 95\% confidence level. The constraints obtained with the method based on the TS distribution under the null hypothesis, which is adopted in many previous astrophysical ALP studies, are also shown. Our results demonstrate that the joint constraints of all the periods from both methods are consistent. However, the latter method fails to provide constraints for some observation periods, whereas the ${\rm CL_s}$ method remains effective in such cases.Comment: 10 pages, 26 figure

Hypoxia-inducible factor-2a is associated with ABCG2 expression, histology-grade and Ki67 expression in breast invasive ductal carcinoma

<p>Abstract</p> <p>Background</p> <p>Breast cancer is the most common cancer and the leading cause of cancer mortality in women worldwide. Hypoxia is an important factor involved in the progression of solid tumors and has been associated with various indicators of tumor metabolism, angiogenesis and metastasis. But little is known about the contribution of Hypoxia-Inducible Factor-2a (HIF-2a) to the drug resistance and the clinicopathological characteristics in breast cancer.</p> <p>Methods</p> <p>Immunohistochemistry was employed on the tissue microarray paraffin sections of surgically removed samples from 196 invasive breast cancer patients with clinicopathological data. The correlations between the expression of HIF-2a and ABCG2 as well as other patients' clinicopathological data were investigated.</p> <p>Results</p> <p>The results showed that HIF-2a was expressed in different intensities and distributions in the tumor cells of the breast invasive ductal carcinoma. A positive staining for HIF-2a was defined as a brown staining observed mainly in the nucleus. A statistically significant correlation was demonstrated between HIF-2a expression and ABCG2 expression (p = 0.001), histology-grade (p = 0.029), and Ki67 (p = 0. 043) respectively.</p> <p>Conclusion</p> <p>HIF-2a was correlated with ABCG2 expression, histology-grade and Ki67 expression in breast invasive ductal carcinoma. HIF-2a could regulate ABCG2 in breast cancer cells, and could be a novel potential bio-marker to predict chemotherapy effectiveness. The hypoxia/HIF-2a/ABCG2 pathway could be a new mechanism of breast cancer multidrug-resistance.</p> <p>Virtual slides</p> <p>http://www.diagnosticpathology.diagnomx.eu/vs/2965948166714795</p

(Acetone-2κO){μ-6,6′-dimeth­oxy-2,2′-[propane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolato-κ81:2O 6,O 1,O 1′,O 6′:O 1,N,N′,O 1′}tris­(nitrato-1κ2 O,O′)copper(II)samarium(III)

In the title heteronuclear complex, [CuSm(C19H20N2O4)(NO3)3(CH3COCH3)], the CuII ion is five-coordinated by two O and two N atoms from the 6,6′-dimeth­oxy-2,2′-[propane-1,2-diylbis(nitrilo­methyl­idyne)]diphenolate ligand (L) and by an O atom from the acetone mol­ecule in a square-pyramidal geometry. The SmIII ion is ten-coordinated by six O atoms from the three nitrate ligands and four O atoms from the L ligand. In L, the C atoms of the diamino­propane fragment are disordered over two positions in a 0.674 (10):0.326 (10) ratio