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Given a graph G and an edge $ e\in E(G) $ e ∈ E (G) , let S be a vertex set of G. For any two vertices x, $ y\in S $ y ∈ S , if e belongs to all the shortest paths between x and y, then x and y can monitor the edge e. For each edge e of G, if there exists x and y in S such that x and y can monitor e, then the set S can be called a monitoring-edge-geodetic ( $ \operatorname {MEG} $ MEG for short) set of G. The $ \operatorname {MEG} $ MEG number, denoted by $ \operatorname {meg}(G) $ meg ⁡ (G) , is the size of the smallest $ \operatorname {MEG} $ MEG set of G. In this paper, we obtain the exact values of the $ \operatorname {MEG} $ MEG numbers for radix triangular mesh networks, Sierpiński graphs, Sierpiński gasket graphs and Sierpiński generalized graphs. [ABSTRACT FROM AUTHOR]

For a set M of vertices and an edge e of a graph G, let $ P_G(M, e) $ P G (M , e) be the set of the pair $ (x, y) $ (x , y) with a vertex x of M and a vertex y of $ V(G) $ V (G) such that $ d_G(x, y)\neq d_{G-e}(x, y) $ d G (x , y) ≠ d G − e (x , y). For a vertex x, let $ EM(x) $ EM (x) be the edge set e such that there exists a vertex v in G with $ (x, v) \in P(\{x\}, e) $ (x , v) ∈ P ({ x } , e). A set M of vertices of a graph G is distance-edge-monitoring set if every edge e of G is monitored by some vertex $ v\in M $ v ∈ M , that is, for any $ e \in E(G) $ e ∈ E (G) , we have $ P_G(M, e)\neq \emptyset $ P G (M , e) ≠ ∅. The distance-edge-monitoring number of a graph G, denoted by $ \operatorname {dem}(G) $ dem ⁡ (G) , is defined as the smallest size of distance-edge-monitoring sets of G. In this paper, we study the distance edge monitoring number of pseudo wheel graphs, that is, some variants of wheel graph. [ABSTRACT FROM AUTHOR]

High-fat diet (HFD) can cause obesity, inducing dysregulation of the visceral adipose tissue (VAT). This study aimed to explore potential biological pathways and hub genes involved in obese VAT, and for that, bioinformatic analysis of multiple datasets was performed. The expression profiles (GSE30247, GSE167311 and GSE79434) were downloaded from Gene Expression Omnibus. Overlapping differentially expressed genes (ODEGs) between normal diet and HFD groups in GSE30247 and GSE167311 were selected to run protein–protein interaction network, GO and KEGG analysis. The hub genes in ODEGs were screened by Cytoscape software and further verified in GSE79434 and obese mouse model. A total of 747 ODEGs (599 up-regulated and 148 down-regulated) were screened, and the GO and KEGG analysis showed that the up-regulated ODEGs were significantly enriched in inflammatory response and extracellular matrix receptor interaction pathways. On the other hand, the down-regulated ODEGs were involved in metabolic pathways; however, there were no significant KEGG pathways. Furthermore, six hub genes, Mki67, Rac2, Itgb2, Emr1, Tyrobp and Csf1r were acquired. These pathways and genes were verified in GSE79434 and VAT of obese mice. This study revealed that HFD induced VAT expansion, inflammation and fibrosis, and the hub genes could be used as therapeutic biomarkers in obesity. [ABSTRACT FROM AUTHOR]

The semi-tensor product, which was initially proposed by Cheng et al. [An introduction to semi-tensor product of matrices and its applications. World Scientific; 2012], has been extensively applied in Boolean control networks, graph colouring, game theory, cryptographic algorithms and so on. In this article, motivated by the existing work by Yao et al. [J Franklin Inst. 2016;353:1109–1131], we further investigate the solvability of the matrix equation AXB=C with respect to semi-tensor product. The case of matrix-vector equation, in which the required unknown X be a vector, is studied first. Compatible condition for matrix dimensions, necessary and sufficient conditions and concrete solving methods are established. Based on this, the solvability of the matrix equation case, in which the unknown X be a matrix, under semi-tensor product is then studied. For each part, several elementary examples are presented to illustrate the efficiency of the results. [ABSTRACT FROM AUTHOR]

Modifying the surface properties of energetic materials has theoretical and practical significance in the field of their application. In this paper, irregular cyclotetramethylene tetranitramine (HMX) particles were successfully coated by energetic nitrocellulose (NC), leading to the uniform NC-coated HMX particles. As coating materials, energetic (NC was chosen to decrease the sensitivity and modify the surface property of HMX particles, in order to expand their application furthermore. Scanning electron microscopy, laser particle size analysis, energy dispersive spectrometer, and Fourier-transform infrared (FT-IR) spectra were utilized to investigate the morphology, size, and coating quality of NC-coated HMX particles. These results indicated the effective preparation of composites structure. Moreover, the thermal behaviors of NC-coated HMX particles were investigated by simultaneous thermogravimetric and differential scanning calorimetry analysis, coupled with FT-IR and mass spectroscopy. These results showed that NC did not induce chemical properties change of HMX, only physical hydrogen bond was formed in the coating process. Finally, the friction sensitivity, impact sensitivity, and surface properties NC-coated HMX were investigated, and the results suggested that NC-coated HMX particles had better safety and depicted stronger interaction with the binder matrix than original HMX, owing to the stability of NC on the outer layer. [ABSTRACT FROM AUTHOR]

Three hurricanes (Frances and Jeanne in 2004 and Wilma in 2005) passed over Lake Okeechobee causing a number of changes in its sediment and environment. The unconsolidated sediment atop the mud sediments in the central region of the lake became thicker due to the settling and deposition of resuspended sediments after the hurricanes passed. The increased unconsolidated sediment layer was more easily resuspended, and resulted in sustained higher solids and nutrient concentrations and lower light transparency in the water column for more than 4 years after the hurricanes passed. Hurricanes Frances and Jeanne disturbed consolidated sediments to a depth of 7-15 cm from the surface while Hurricane Wilma extended the disturbance to a depth of 25 cm. Concentrations of total suspended solids (TSS) in the water column increased four to sixfold after the hurricanes. The high concentration of TSS was continuous and maintained 2-4 times higher than a normal situation in the lake until present. Hurricanes contributed to a decrease of submerged aquatic vegetation (SAV) density from 4-34 g dw/m2 to 0.1-4 g dw/m2 primarily through scouring. SAV recovery was very slow due to the increasing turbidity and reduced light transparency. [ABSTRACT FROM AUTHOR]

Eight alkaline and alkaline-earth compounds derived from 2,4-dinitroimidazole (2,4-HDNI) were synthesized and characterized by elemental analysis, FT-IR, and TG-DSC, of which K(2,4-DNI) (1), Rb(2,4-DNI)(2,4-HDNI)(H2O)2 (2), and Ba(2,4-DNI)2(H2O)4 (3) were characterized by single-crystal X-ray diffraction analysis. All the three compounds were crystallized from water, but 1 was an anhydrate. The coordination number in 1 and 3 is 10, but in 2 is 9. The 2,4-DNI adopts either η3, η2, or η1 coordination modes depending on the metal cation. In 3, there is an inversion center located on the metal. Only in 2 does water play an important role for the construction of the structure; in 3 it is a hydrogen bonding participant. TG-DSC analyses of 1 were also performed, and non-isothermal decomposition reaction kinetics were obtained. [ABSTRACT FROM AUTHOR]

Three neodymium compounds, Nd(4DNP)3(C2H5OH)3 (1), Nd(4DNPO)3 · 7H2O (2), and {[Nd(μ-ox)(4DNPO)(H2O)4] · 4H2O}n (3) (4HDNP, 3,5-dinitropyrid-4-one; 4HDNPO, 3,5-dinitropyrid-4-one-N-hydroxide; ox, oxalate), were synthesized and characterized by FT-IR, elemental analysis, thermogravimetry-differential scanning calorimetry (TG-DSC), and two of them by single-crystal X-ray diffraction analyses. The results revealed that in 1, the Nd(III) is surrounded by three chelating ligands and three ethanol solvent molecules. The structure of 3 could be described as 1-D chains in which Nd is bis-bidentately bridged by oxalates, together with a monodentate 3,5-dinitropyrid-4-onate N-oxide 4DNPO ligand and four water molecules as well as four uncoordinated water molecules in the crystal lattice. The origin of the oxalate anions in 3 is probably due to decomposition of the 4DNPO or its oxidation of other species. The TG-DTG (DTG, derivative thermogravimetry) and DSC analyses showed that 1 underwent a three-stage decomposition process. A kinetic equation for decomposition reaction of 2 was also obtained. The apparent activation energy (Ea) and pre-exponential factor (A) of the main decomposition reaction are 157.70 kJ mol-1 and 1011.97 s-1, respectively. The kinetic equation can thus be expressed as dα/dt = 1011.97(1 - α)e-1.90 × 104/T. [ABSTRACT FROM AUTHOR]

Two trinuclear Ni(II) complexes Ni3(L1)2(py)2(DMF)(H2O) (1) and Ni3(L2)2(py)2(DMF)2 (2) with two new trianionic pentadentate ligands N-(3,5-dimethylbenzoyl)-salicylhydrazide (H3L1) and N-(phenylacetyl)-5-nitrosalicylhydrazide (H3L2) have been synthesized and characterized by X-ray crystallography. Nickel ions in the two complexes have square-planar/octahedral/square-planar coordination. Central metal ion and two terminal metal ions in the two complexes are combined by two bridging deprotonated ligands, forming a trinuclear structural unit with an M-N-N-M-N-N-M core. Studies on the trinuclear Ni(II) complexes show that the β-branched N-acylsalicylhydrazide ligands with sterically flexible Cα methylene groups yield linear trinuclear Ni(II) complexes, while α-branched N-acylsalicylhydrazide ligands tend to form bent trinuclear Ni(II) complexes. Antibacterial screening data in a previous study indicates that bent trinuclear Ni(II) compound 1 is more active than linear compound 2 and less active than a tetranuclear nickel compound. [ABSTRACT FROM AUTHOR]

Three new energetic compounds, nickel(II) 3,5-dinitro-2-pyridonate (Ni(2DNPO)2(H2O)4, 1), copper(II) 3,5-dinitro-4-pyridonate (Cu(4DNPO)2(H2O)4, 2) and cobalt(II) 3,5-dinitro-4-pyridone-N-hydroxylate ([Co(4DNPOH)2(H2O)4] · 2DMF, 3 · 2DMF), were characterized by elemental analysis, FT-IR, TG-DSC and X-ray single crystal diffraction analysis. Complexes 1 and 2 are similar in structure with the metal ion coordinated by oxygen donors of four water molecules on the equatorial position and two nitrogen donors of the pyridone rings of two ligands in the axial positions. The cobalt(II) complex 3 · 2DMF is a heavily distorted octahedral geometry. The Co(II) has equatorial positions defined by oxygens of four water molecules. Its axial positions are filled with two oxygen atoms of the pyridone-N-hydroxylate of two ligands. The TG-DSC results reveal that 1 is the most stable, with higher initial thermal decomposition temperature and enthalpy. Based on the thermoanalyses, the nickel compound is a promising candidate as a component in catalyzed RDX-CMDB propellants in comparison with our earlier lead(II) analogs. [ABSTRACT FROM AUTHOR]

Six complexes, rubidium and cesium 3,5-dinitropyrid-2-onate (2DNPO), 3,5-dinitropyrid-4-onate (4NDPO), 3,5-dinitropyrid-4-one-N-hydroxylate (4DNPNO), were synthesized and characterized by elemental analysis, FT-IR, TG-DTG and X-ray single-crystal diffraction analysis. All the complexes crystallized from water and one of them was a hydrate. Rubidium 3,5-dinitropyrid-4-one-N-hydroxylate was crystallized with the 1 : 2 stoichiometry as Rb[H(4DNPNO)2] upon absorption of carbon dioxide. The structural determinations showed that the coordination sphere around a metal centre is made up of oxygen atoms and nitrogen atoms, except for the 4DNPNO complexes, where the coordination sphere accommodates exclusively oxygen atoms. The coordination numbers of the metal centers vary from 8, 10, 11 to 12, while the ligands, each employing its pyridone tautomer, link with metal cations. Bridging oxygen atoms play an important role in construction of two- and/or three-dimensional networks of these complexes. Hydrogen bonding contributes to the connectivity within a given sheet in Rb[H(4DNPNO)2]; aromatic π-π stacking interactions exist only in Cs(4DNPNO). The interactions between metal atoms and ligands are generally very weak. The organization of all layer structures appears to be governed mainly by steric effects and electrostatic forces with very little directional influence of the cations. The thermogravimetric analyses of these complexes showed the following consecutive processes: loss of NO2 groups, collapse of the pyridyl ring backbones and finally inorganic residue formation. These complexes could be used as probes in template effects of heavy alkali-metal cations in the organization of biorelevant ligands and as environment-friendly energetic catalysts in solid propellants. [ABSTRACT FROM AUTHOR]

A macrocyclic iron(III) 18-azametallacrown-6 compound, [Fe6(5-Brashz)6(H2O)6] · 20H2O(5-Brashz = N-acetyl-(5-bromosalicylhydrazide)), where the pentadentate ligands bridge the metal ions, was synthesized and characterized. Due to the meridional coordination of the ligand to the metal ion, the ligand is not only bridging the ring metal ions using a hydrazide N-N group, but also enforcing the stereochemistry of the metal ions as a propeller shape with alternating Λ/Δ configuration. The disc-shaped hexanuclear cluster is about 14.5 Å in diameter, 16.8 Å in thickness and has a vacant cavity in the center of the cluster. [ABSTRACT FROM AUTHOR]

Sulfides can be selectively converted to corresponding sulfoxides in excellent yields under mild conditions by linear and 1% cross‐linked poly[4‐hydroxy(tosyloxy)iodo]styrene (PSHTIB). [ABSTRACT FROM AUTHOR]

Arenecarbaldehyde-4-arylthiazol-2-ylhydrazones underwent ring closure with poly[(4-diacetoxyiodo)styrene] (PSDIB) to 3,5-diarylthiazolo[2,3-c]-s-triazoles in dichloromethane. [ABSTRACT FROM AUTHOR]

Racemic cis-BCH-189 can be resolved to (-)-enantiomer (lamivudine) and (+)-enantiomer by esterification of cis-2-hydroxymethyl-5-(-acetylcytosine-1′-yl)-1,3-oxathiolane and (+)-menthyl chloroformate in CH3CN with pyridine as base. The two diastereomers of ester were separated by recrystallization in methanol at 0°C. Lamivudine was obtained by deprotection of (-)-diastereomer with high yield. [ABSTRACT FROM AUTHOR]

AbstractIn this paper, a nonclassical shell model is utilized to investigate the dynamic stability of functionally graded piezoelectric (FGP) nanoshells considering the thermo-electro-mechanical coupling effects. Also, the FGP nanoshells on elastic foundations are subjected to periodic axial loading. The theoretical formulations are derived by implementing the first-order shear deformation (FSD) shell theory into the nonlocal strain gradient theory (NSGT). Hamilton’s principle is utilized to obtain the equations of motion and related boundary conditions of the present nanoshell model. Moreover, the Mathieu-Hill equations determining the instability regions are presented and analyzed based on Bolotin’s method. Results demonstrate that the external electric voltage, the elastic foundations, the temperature rise, the static load factor, the power-law index and the small-scale parameters have significant influences on the dynamic stability responses of FGP nanoshells. [ABSTRACT FROM AUTHOR]