Poly[[μ2-1,3-bis­(imidazol-1-ylmeth­yl)benzene][μ2-2,2′-dihy­droxy-1,1′-methyl­enebis(naphthalene-3-carboxyl­ato)]zinc]

In the title compound, [Zn(C23H14O6)(C14H14N4)]n, the ZnII ion is four-coordinated in a distorted tetra­hedral geometry. The 1,3-bis­(imidazol-1-ylmeth­yl)benzene and 2,2′-dihy­droxy-1,1′-methyl­enebis(naphthalene-3-carboxy­l­ate) ligands con­nect the ZnII ions alternately in different directions, forming a layered structure parallel to the ac plane. Topological analysis reveals that the whole structure is a (4,4) network. The layers are further assembled into a three-dimensional supra­molecular structure via C—H⋯O and C—H⋯π inter­actions

Double band inversion in the topological phase transition of Ge1-xSnx alloys

We use first-principles simulation and virtual crystal approximation to reveal the unique double band inversion and topological phase transition in Ge1-xSnx alloys. Wavefunction parity, spatial charge distribution and surface state spectrum analyses suggest that the band inversion in Ge1-xSnx is relayed by its first valence band. As the system evolves from Ge to {\alpha}-Sn, its conduction band moves down, and inverts with the first and the second valence bands consecutively. The first band inversion makes the system nontrivial, while the second one does not change the topological invariant of the system. Both the band inversions yield surface modes spanning the individual inverted gaps, but only the surface mode in the upper gap associates with the nontrivial nature of tensile-strained {\alpha}-Sn.Comment: 5 pages, 6 figure

Effect of the Deformation Degree on the Microstructure Evolution of an Austenite Reverted Transformation-Annealed Medium Manganese Steel

An Fe-0.15C-1.2Si-5Mn-0.09Nb-0.08V-0.07Mo (wt.%) medium manganese steel that was subjected to a novel austenite reverted transformation (ART) annealing process. This paper is based on the conventional ART annealing process, and a deformation and ART annealing process is proposed. The influence of the deformation degree on the microstructure and grain size of the medium manganese steel was determined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). The results show that the deformation had a great effect on the microstructure evolution and grain size. The microstructure of the medium manganese steel after the deformation and ART annealing process was consistent with the theory of austenite reverse transformation, i.e., the martensite reverse transformation into austenite occurred during the deformation and ART annealing process. The final microstructure was a mixture of martensite and austenite. As the deformation degree increases, the martensite gradually refines, and carbides precipitate in the lath martensite. The retained austenite is gradually transformed from very large to small and is distributed between the martensite laths. The results show that when deformation occurs in the austenite region, a small deformation can obtain more retained austenite

A novel sample preparation method for ultra-high vacuum (UHV) secondary ion mass spectrometry (SIMS) analysis

Secondary ion mass spectrometry (SIMS) has been applied to analyze a wide range of materials for earth science research due to its high sensitivity, high precision and capacity for in situ micro-analysis. This technique operates under ultra-high vacuum (UHV) conditions, especially for water content measurements on nominally anhydrous minerals (NAMs). However, UHV conditions are hard to achieve when using epoxy mounts, which degas readily during the vacuum processes. In this study, we developed a novel sample preparation method using a tin-based alloy instead of epoxy resin. Using a tin alloy mount coupled with an automatic liquid nitrogen refilling system, the results show that the vacuum conditions have been significantly improved from approximate to 1.2 x 10(-8) mbar to approximate to 1.9 x 10(-9) mbar. The background for mineral water content, measured with a CAMECA IMS 1280-HR SIMS installed at the Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (GIGCAS), is lowered to <10 ppm. Moreover, tin alloy mounts are harder and easier to polish than indium mounts, which was commonly used for previous UHV analyses. A relief of <2 m is yielded for tin alloy mounts, which is essential for high precision isotope analysis. Our results also show that the routine external precision of oxygen isotope ratios is better than 0.15 parts per thousand (1SD), comparable with that obtained using epoxy mounts

The IR Characteristics Modeling and Simulation of the HEO Target

Space target infrared (IR) characteristics model can be used to design space target detection sensor, generating simulation data to validate the data processing algorithms, such as target detection and tracking. In the work, a HEO target IR characteristics model is built. The model consists of the geometry module and the IR radiometric module. Unlike the traditional space IR model, the temperature of cabin inner is used as the simulation origin. Using the model, the irradiance spectra of HEO target are calculated for different target temperature. With the calculation results, the main wavelength range for HEO detection is analyzed. Using the equvalent temperature, the work also designs a simulative target, which has the similar IR characteristics of a HEO target. The simulator can be used in the ground test for the imaging sensor or target decoy

Increased Serum ANGPTL8 Concentrations in Patients with Prediabetes and Type 2 Diabetes

The objectives of the study were to investigate serum ANGPTL8 concentrations in different glucose metabolic statuses and to explore the correlations between serum ANGPTL8 levels and various metabolic parameters. Serum ANGPTL8 levels were determined using ELISA in 22 subjects with NGT (normal glucose tolerance), 74 subjects with IGR (impaired glucose regulation), and 33 subjects with T2DM (type 2 diabetes mellitus). Subjects with IFG, IGT, CGI, and T2DM had higher levels of serum ANGPTL8 than subjects with NGT. Serum ANGPTL8 was positively correlated with FPG, fasting C-peptide, and postprandial C-peptide and negatively correlated with BETA/IR when adjusted for age and BMI. Multivariate analysis suggested FPG and fasting C-peptide as independent factors associated with serum ANGPTL8 levels. Serum ANGPTL8 concentrations were significantly increased in IGR and T2DM. Serum ANGPTL8 might play a role in the pathological mechanism of glucose intolerance

The IR Characteristics Modeling and Simulation of the HEO Target

Space target infrared (IR) characteristics model can be used to design space target detection sensor, generating simulation data to validate the data processing algorithms, such as target detection and tracking. In the work, a HEO target IR characteristics model is built. The model consists of the geometry module and the IR radiometric module. Unlike the traditional space IR model, the temperature of cabin inner is used as the simulation origin. Using the model, the irradiance spectra of HEO target are calculated for different target temperature. With the calculation results, the main wavelength range for HEO detection is analyzed. Using the equvalent temperature, the work also designs a simulative target, which has the similar IR characteristics of a HEO target. The simulator can be used in the ground test for the imaging sensor or target decoy

Midkine, a potential link between obesity and insulin resistance.

Obesity is associated with increased production of inflammatory mediators in adipose tissue, which contributes to chronic inflammation and insulin resistance. Midkine (MK) is a heparin-binding growth factor with potent proinflammatory activities. We aimed to test whether MK is associated with obesity and has a role in insulin resistance. It was found that MK was expressed in adipocytes and regulated by inflammatory modulators (TNF-α and rosiglitazone). In addition, a significant increase in MK levels was observed in adipose tissue of obese ob/ob mice as well as in serum of overweight/obese subjects when compared with their respective controls. In vitro studies further revealed that MK impaired insulin signaling in 3T3-L1 adipocytes, as indicated by reduced phosphorylation of Akt and IRS-1 and decreased translocation of glucose transporter 4 (GLUT4) to the plasma membrane in response to insulin stimulation. Moreover, MK activated the STAT3-suppressor of cytokine signaling 3 (SOCS3) pathway in adipocytes. Thus, MK is a novel adipocyte-secreted factor associated with obesity and inhibition of insulin signaling in adipocytes. It may provide a potential link between obesity and insulin resistance