A Novel Model of Conforming Delaunay Triangulation for Sensor Network Configuration

Delaunay refinement is a technique for generating unstructured meshes of triangles for sensor network configuration engineering practice. A new method for solving Delaunay triangulation problem is proposed in this paper, which is called endpoint triangle’s circumcircle model (ETCM). As compared with the original fractional node refinement algorithms, the proposed algorithm can get well refinement stability with least time cost. Simulations are performed under five aspects including refinement stability, the number of additional nodes, time cost, mesh quality after intruding additional nodes, and the aspect ratio improved by single additional node. All experimental results show the advantages of the proposed algorithm as compared with the existing algorithms and confirm the algorithm analysis sufficiently

Phase evolution of Ce-based heavy-fermion superconductors under pressure: a combined DFT+DMFT and effective-model description

In typical Ce-based heavy-fermion superconductors, superconducting (SC) phases emerge or can be tuned in proximity to the antiferromagnetic (AF) quantum critical point (QCP), but so far the explicit phase-evolution process and the coexistence of superconductivity and AF order near the QCP remain lack of understanding. Here, by combing DFT+DMFT with effective-model calculations, we provide a theoretical description for Ce-based SC compounds under pressure. Firstly, DFT+DMFT calculations for the normal states reveal that the Kondo hybridizations are significantly enhanced, while the initially localized $f$ electrons eventually become fully itinerant via a localized-itinerant crossover. In this context, we construct an effective model with tunable parameters under pressure, and show that the interplay of magnetic correlation and Kondo hybridization can drive successive transitions, from AF phase to AF+SC coexisting phase, then to paramagnetic SC phase via an AF transition which corresponds to the QCP, and finally to Kondo paramagnetic phase through a SC transition driven by localized-itinerant crossover. Our study gives a proper explanation for the pressure-induced magnetic QCP and SC transition, and for the phase-evolution process under pressure in typical Ce-based superconductors, and may also help to understand the SC states emerging around the ferromagnetic quantum transition points in uranium-based superconductors.Comment: 13 pages, 11 figure

Poly[[diaqua­(μ4-1H-benzimidazole-5,6-dicarboxyl­ato)strontium] monohydrate]

Each of the carboxyl­ate –CO2 fragments of the dianion ligand in the title compound, {[Sr(C9H4N2O4)(H2O)2]·H2O}n, chelates to a SrII atom and at the same time, one of the two O atoms coordinates to a third SrII atom. The μ4-bridging mode of the dianion generates a square-grid layer motif; adjacent layers are connected by O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds, forming a three-dimensional network. The eight-coordinate Sr atom exists in a distorted square-anti­prismatic geometry. The crystal studied was a non-merohedral twin with a minor twin component of 24%

Homologous haplotypes, expression, genetic effects and geographic distribution of the wheat yield gene TaGW2

BACKGROUND: TaGW2-6A, cloned in earlier research, strongly influences wheat grain width and TKW. Here, we mainly analyzed haplotypes of TaGW2-6B and their effects on TKW and interaction with haplotypes at TaGW2-6A. RESULTS: About 2.9 kb of the promoter sequences of TaGW2-6B and TaGW2-6D were cloned in 34 bread wheat cultivars. Eleven SNPs were detected in the promoter region of TaGW2-6B, forming 4 haplotypes, but no divergence was detected in the TaGW2-6D promoter or coding region. Three molecular markers including CAPS, dCAPS and ACAS, were developed to distinguish the TaGW2-6B haplotypes. Haplotype association analysis indicated that TaGW2-6B has a stronger influence than TaGW2-6A on TKW, and Hap-6B-1 was a favored haplotype increasing grain width and weight that had undergone strong positive selection in global wheat breeding. However, clear geographic distribution differences for TaGW2-6A haplotypes were found; Hap-6A-A was favored in Chinese, Australian and Russian cultivars, whereas Hap-6A-G was preferred in European, American and CIMMYT cultivars. This difference might be caused by a flowering and maturity time difference between the two haplotypes. Hap-6A-A is the earlier type. Haplotype interaction analysis between TaGW2-6A and TaGW2-6B showed additive effects between the favored haplotypes. Hap-6A-A/Hap-6B-1 was the best combination to increase TKW. Relative expression analysis of the three TaGW2 homoeologous genes in 22 cultivars revealed that TaGW2-6A underwent the highest expression. TaGW2-6D was the least expressed during grain development and TaGW2-6B was intermediate. Diversity of the three genes was negatively correlated with their effect on TKW. CONCLUSIONS: Genetic effects, expression patterns and historic changes of haplotypes at three homoeologous genes of TaGW2 influencing yield were dissected in wheat cultivars. Strong and constant selection to favored haplotypes has been found in global wheat breeding during the past century. This research also provides a valuable case for understanding interaction of genes that control complex traits in polyploid species

Translocator protein activates autophagy in diabetic neuropathic pain rats via regulation of the Keap1/Nrf2/HO-1 signaling

Objective·To study the effects of translocator protein (TSPO) agonist Ro5-4864 on autophagy and Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid-derived-2-like 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling in diabetic neuropathic pain (DNP) rats.Methods·Type 2 diabetic rats were established by high-fat diet and streptozotocin (STZ), and DNP rats were filtered by behavioral assessment. Twenty-four rats were randomly assigned to the Sham group, DNP group, TSPO agonist Ro5-4864 group (Ro group), and TSPO agonist Ro5-4864 combined with Nrf2 inhibitor ML385 group (Ro+ML385 group). Up-Down method was used to measure paw 50% mechanical withdrawal threshold (50% PMWT) of the rats before high-fat diet (baseline), and on Day 3, 7, 14, 21 and 28 after STZ. Sciatic nerves were collected on the last day to analyze the effects of Ro5-4864 on autophagy related proteins and Keap1/Nrf2/HO-1 signaling related proteins of DNP rats by using immunofluorescence and Western blotting.Results·The 50% PMWT in the DNP group decreased from D3 to D28 (P=0.000 at all timing), and the expression of Bcl-2 interacting coiled-coil protein 1 (Beclin-1), microtubule-associated protein light chain 3-Ⅱ (LC3-Ⅱ), HO-1, and nuclear Nrf2 (P=0.000) were significantly reduced in the sciatic nerves of DNP rats (all P=0.000), compared with those in the sham group, but p62 was significantly increased (P=0.000). Administration of Ro5-4864 attenuated these changes in the rats of the Ro group. There was a gradual increase in the 50% PMWT, compared with that of the rats in the DNP group (D14 P=0.039, both D21 and D28 P=0.000), and the impairment of autophagy and the Keap1/Nrf2/HO-1 signaling was repaired, which was demonstrated by increases of Beclin-1, LC3-Ⅱ, HO-1, and nuclear Nrf2 protein contents (all P=0.000) and a decrease in p62 content (P=0.001). However, the beneficial effects of Ro5-4864 were totally abrogated by ML385 in rats of the Ro+ML385 group.Conclusion·TSPO alleviates DNP in rats, of which the mechanism involves activation of autophagy via upregulation of the Keap1/Nrf2/HO-1 signaling in sciatic nerves. This study provides a new strategy for the treatment of DNP

Node-line Dirac semimetal manipulated by Kondo mechanism in nonsymmorphic CePt2_2Si2_2

Dirac node lines (DNLs) are characterized by Dirac-type linear crossings between valence and conduction bands along one-dimensional node lines in the Brillouin zone (BZ). Spin-orbit coupling (SOC) usually shifts the degeneracy at the crossings thus destroys DNLs, and so far the reported DNLs in a few materials are non-interacting type, making the search for robust interacting DNLs in real materials appealing. Here, via first-principle calculations, we reveal that Kondo interaction together with nonsymmorphic lattice symmetries can drive a robust interacting DNLs in a Kondo semimetal CePt_2Si_2, and the feature of DNLs can be significantly manipulated by Kondo behavior in different temperature regions. Based on the density function theory combining dynamical mean-field theory (DFT+DMFT), we predict a transition to Kondo-coherent state at coherent temperature T_coh= 80 K upon cooling, verified by temperature dependence of Ce-4f self-energy, Kondo resonance peak, magnetic susceptibility and momentum-resolved spectral. Below T_coh, well-resolved narrow heavy-fermion bands emerge near the Fermi level, constructing clearly visualized interacting DNLs locating at the BZ boundary, in which the Dirac fermions have strongly enhanced effective mass and reduced velocity. In contrast, above a crossover temperature T_KS =600 K, the destruction of local Kondo screening drives non-interacting DNLs which are comprised by light conduction electrons at the same location. These DNLs are protected by lattice nonsymmorphic symmetries thus robust under intrinsic strong SOC. Our proposal of DNLs which can be significantly manipulated according to Kondo behavior provides an unique realization of interacting Dirac semimetals in real strongly correlated materials, and serves as a convenient platform to investigate the effect of electronic correlations on topological materials.Comment: 9 pages, 9 figure

Poly[diaqua­(μ3-1H-benzimidazole-5,6-dicarboxyl­ato-κ4 N 3:O 5,O 6:O 6′)magnesium(II)]

In the title complex, [Mg(C9H4N2O4)(H2O)2]n, the MgII atom is six-coordinated by one N and three O atoms from three different 1H-benzimidazole-5,6-dicarboxyl­ate ligands and two O atoms from two water mol­ecules, forming a slightly distorted octa­hedral geometry. The ligand links the MgII centres into a three-dimensional network. Extensive N—H⋯O and O—H⋯O hydrogen bonds exist between the ligands and water mol­ecules, stabilizing the crystal structure