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The half-metallic calculations of new variant perovskites Li2CrO6 and Li2CuO6 were carried out by using WIEN2k computational code. First, the ferromagnetic (FM) and non-magnetic (NM) phases were compared, and FM phases were obtained energetically more stable. The equilibrium lattice constants were obtained as 7.63 Å and 7.66 Å for Li2CrO6 and Li2CuO6, respectively. Second, the electronic calculations were performed, and the semiconduction properties were seen in spin-up states while spin-down states showed metallic nature. The band gaps were obtained as 1.806 eV and 1.177 eV for Li2CrO6 and Li2CuO6, respectively. Since variant perovskites Li2CrO6 and Li2CuO6 showed 100% spin polarizations, these were obtained as true half-metallic ferromagnetic materials. Then the total magnetic moments were obtained as 4.00 μB/f.u., 5.00 μB/f.u. When both the electronic and magnetic properties of the compounds are examined, the variant perovskites Li2CrO6 and Li2CuO6 are suitable materials for spintronics applications.

This article asserts the importance of public participation in local government, through social action research, in order to achieve good governance. We examine how bad local governance negatively impacts the socio-economic development trajectory of communities. Based on fieldwork conducted in the Eastern Cape province of South Africa, this article illustrates the transformative role participatory processes and good governance played as peacebuilding mechanisms to achieve positive peace in the Mbizana local municipality. The municipality’s geography spans from deep rural areas to the urban central business district (CBD). A mixed qual-quant methodology with a phased rollout was applied to engage the local government and communities involved, and target with precision the lived reality of the residents. The findings of the study point to the transformative nature of the local participatory processes that entailed building confidence between the municipal authorities, the NGO Good Governance Africa (GGA) and the Mbizana community, and new ideas on how to facilitate public participation. Our conclusion is that civil society organisations should build trust with local authorities in communities for public participation interventions to be successful. This outlook differs to perceiving local authorities as a threat or barrier to direct interventions. The combination of participatory processes and good governance restored the community’s confidence in the municipality through shared governance information and capacity building. This hybrid approach can be replicated and applied to promote sustainable peace in communities that face similar challenges.

Since the last decade, the half-Heusler (HH) compounds have taken an important place in the field of the condensed matter physics research. The multiplicity of substitutions of transition elements at the crystallographic sites X, Y and (III-V) elements at the Z sites, gives to the HH alloys a multitudes of remarkable properties. In the present study, we examined the structural, electronic and thermoelectric properties of ZrCoBi0.75Z0.25 (Z = P, As, Sb) using density functional theory (DFT). The computations have been done parallel to the full potential linearized augmented plane wave (FP-LAPW) method as implemented in the WIEN2k code. The thermoelectrically properties were predicted via the semi-classical Boltzmann transport theory, as performed in Boltztrap code. The obtained results for the band structure and densities of states confirm the semiconductor (SC) nature of the three compounds with an indirect band gap, which is around 1eV. The main thermoelectric parameters such as Seebeck coefficient, thermal conductivity, electrical conductivity and figure of merit were estimated for temperatures ranging from zero to 1200K. The positive values of Seebeck coefficient (S) confirm that the ZrCoBi0.75Z0.25 (x = 0 and 0.25) are a p-type SC. At the ambient temperature, ZrCoBi0.75P0.25 exhibit the large S value of 289 µV/K, which constitutes an improvement of 22% than the undoped ZrCoBi, and show also a reduction of 54% in thermal conductivity (κ/τ). The undoped ZrCoBi has the lowest ZT value at all temperatures and by substituting bismuth atom by one of the sp elements (P, As, Sb), a simultaneous improvement in κ/τ and S have led to maximum figure of merit (ZT) values of about 0.84 obtained at 1200 K for the three-doped compounds.

Hydraulic solvers for the simulation of flows and pressures in water distribution systems (WDS) are used extensively, and their computational performance is key when considering optimization problems. This paper presents an approach to speedup the hydraulic solver using OpenMP with two efficient methods for WDS simulation. The paper identifies the different tasks carried out in the simulation, showing their contribution to the execution time, and selecting the target tasks for parallelization. After describing the algorithms for the selected tasks, parallel OpenMP versions are derived, with emphasis on the task of linear system update. Results are presented for four different large WDS models, showing considerable reduction in computing time, This work has been partially supported by Ministerio de Economia y Competitividad from Spain, under the project TEC2012-38142-C04-01, and by project PROMETEO FASE II 2014/003 of Generalitat Valenciana.

The crystal structure of Bi2Se3 using ab initio calculations have been investigated using density functional theory (DFT). According to the atomic positions provided by the previous literature, we were able to construct a lattice structure using visualization software Material Studio. This structure is found in rhombohedral, of the space group D53d with R3m (#166) and lattice parameter of a = b = 4.143 A, c = 28.836 A, and the bond angle of α = β = 90°, γ = 120°, while treating the exchange-correlation potential with the general gradient Approximations (GGA) method. The structural calculations were performed to investigate, the electronic, charge density, optical, and phonon properties. To conclude, the partial density of state plots indicates the material properties near to the fermi level determined by the p state orbitals.

WOS: 000355571800008, The absorption and fluorescence spectra of three 2-((phenylimino)methyl)phenol derivatives have been evaluated in a series of organic solvents. The ground state (mu(g)) and excited state (mu(e)) dipole moments are determined by means of Lippert-Mataga, Bakhshiev, Kaski-Chamma-Viallet and Reichardt solvatochromic shift methods based on the solvent polarity parameters. Excited state dipole moments are found as larger than the ground state dipole moment due to substantial redistribution of the pi-electron density in more polar excited state and thus resonance structures of 2-((phenylimino)methyl)phenol derivatives are analyzed. Solute-solvent interactions are analyzed by means of linear solvation energy relationships (LSER) using dielectric constant function f(epsilon), refractive index function f(n) and Kamlet-Taft parameters (H-bond donor ability, alpha and H-bond acceptor ability, beta). External electric field (EF) effect on HOMO-LUMO gap (HLG) and dipole moment are investigated by B3LYP, LDA and GGA methods. Density of states (DOS) and HOMO, LUMO plots are also investigated by the same methods, Bitlis Eren University, Scientific and Technological Application and Research Center; Bitlis Eren University Research Foundation [BEBAP-2014.05], The authors greatly acknowledge the support of Bitlis Eren University, Scientific and Technological Application and Research Center.; The authors greatly appreciate Bitlis Eren University Research Foundation for financial support. Project number: BEBAP-2014.05.

Electronic and magnetic properties of transition-metal oxides are a continuing research theme due to the variety of ground states and their technological applications. In the present paper, we present first-principles calculations using the full-potential linear augmented plane-wave methods (FP-LAPW) on the structural, electronic and magnetic properties of tree cubic (Pm–3m space group) perovskite oxides SrRuO3, BaRuO3, and CaRuO3 in comparison with other phases ((4H) four-layered hexagonal (P63/mmc space group), (2H) two-layered hexagonal (P63/mmc space group) and orthorhombic (Pnma space group). The current study is given within the density-functional theory basis DFT. The exchange-correlation potential is introduced by different approaches. We computed the equilibrium lattices, bulk modulus and its pressure derivatives and equilibrium volume. Our obtained results agree successfully with the theoretical and experimental data. The spin magnetic moments of these oxides have been obtained to investigate the magnetic properties. We report a detailed analysis of the different ground states properties for considerable oxides using GGA and GGA-modified Becke–Johnson computational approaches.

We present density functional theory (DFT) calculation results of krypton and xenon atoms interaction on the surface of uranium dioxide single crystal. A pseudo-potential approach in the generalised gradient approximation (GGA) was applied using the ABINIT program package. To compute the unit cell parameters, the 25 atom super-cell was chosen. It has been revealed that close to the surface of a potential well is formed for xenon and krypton atom due to its interaction with the atoms of oxygen and uranium. Depth and shape of the well is the subject of ab initio calculations in adiabatic approximation. The calculations were performed both for the case of oxygenic and metallic surfaces. It has been shown that the potential well for the oxygenic surface is deeper than for the metallic surface. The thermal stability of immobilising the atoms of krypton and xenon in the potential wells were evaluated. The results are shown in graphs.

International audience; The overall large ionic character of MgH2 is reduced by inserting light elements from the first period, B and C, using a trirutile host superstructure. From DFT computations, both elements are found destabilizing to the structure with largely positive cohesive energy with interstitial B and slightly negative cohesive energy with interstitial C. This trend is also observed for low amounts of insertion down to (B,C)0.167MgH2. From the Bader charge analysis the largely ionic character of hydrogen is decreased to an average H−0.37 in the neighborhood of C and H−0.75 for the other hydrogen atoms (resp. H−0.64 and H−0.76 for B insertion). This peculiar behavior should enable enhancing the kinetics of H release for potential applications.

International audience; Stability of different phases of AMoO4 (A = Mg, Ni) molybdates versus A–O bonding and the corresponding electronic structures are examined from first principles. The energy-volume equations of state for three forms (β, α, ω), characterized by decreasing volumes in the sequence of Mg and Ni molybdates are established. While NiMoO4 is energy stabilized in the sequence β → α → ω, an opposite behavior is identified for the Mg molybdate. Charge analysis characterizing ionic Mg2+ versus covalent Ni+1.2 behaviors can explain the trend. Electronic band structure also shows large differences: MgMoO4 is insulating with a 2 eV band gap while in a magnetic state, NiMoO4 is a small gap (0.2 eV) semi-conductor. Chemical bonding properties show weak Mg and strong Ni bonding with oxygen, while identifying the Mo–O interaction as prevailing.

The adsorption of three simple azole molecules—imidazole, triazole, and tetrazole—and Cl on various sites of several Cu 2 O(111)- and Cu 2 O(110)-type surfaces, including Cu and O vacancies, was characterized using density functional theory (DFT) calculations; the three molecules can be seen as models of azole corrosion inhibitors and Cl as a corrosion activator. Both non-dissociative and dissociative adsorption modes were considered for azole molecules; the latter involves the N–H bond cleavage, hence we also addressed the adsorption of H, which is a co-product of the dissociative adsorption. We find that molecules and Cl bind much stronger to unsaturated Cu sites compared to saturated ones. Dissociated molecules bind considerably stronger to the surface compared to the intact molecules, although even the latter can bind rather strongly to specific unsaturated Cu sites. Bader analysis reveals that binding energies of dissociated molecules at various Cu sites correlate with Bader charges of Cu ions before molecular adsorption, i.e., the smaller the Cu charge, the stronger the molecular bonding. All three azole molecules display similar non-dissociative adsorption energies, but significant difference between them appears for dissociative adsorption mode, i.e., dissociated triazole and tetrazole bind much stronger than dissociated imidazole because the former two can form two strong N–Cu bonds, but imidazole cannot due to its incompatible molecular geometry. Dissociative adsorption is consequently favorable only for triazole and tetrazole, but only at oxygen vacancy sites, where it proceeds barrierlessly (or almost so). This observation may suggest that, for imidazole, only the neutral form, but, for triazole and tetrazole, also their deprotonated forms are the active species for inhibiting corrosion under near neutral pH conditions, where copper surfaces are expected to be oxidized. As for the comparison with the Cl–surface bonding, the calculations indicate that only dissociated triazole and tetrazole bind strong enough to rival the Cl–surface bonds.

International audience; Within density functional theory the equations of state for perovskite (PV) and post-perovskite (PPV) forms of CaRhO3 are obtained with equilibrium values of volume in agreement with experiment. Energy magnitudes point to a stabilization of PPV versus PV. This is interpreted by analyses of the charge density and the chemical bonding plots, showing that the Rh–O interactions within two oxygen sublattices are selectively differentiated and reinforced for one of the two oxygen sublattices within PPV variety with respect to PV one. Investigation of the magnetic properties shows no magnetic order and a metallic character for PV while ferromagnetism occurs in PPV with a tendency to insulating behavior. This long range order is favored by direct t2g–t2g interactions through edge sharing octahedra in PPV CaRhO3, stronger than indirect t2g–pπ–t2g ones in PV variety.

Auxilin is a cofactor for Hsc70-mediated uncoating of clathrin-coated vesicles (CCVs). However, small interfering RNA (siRNA) knockdown of the ubiquitous auxilin 2 in HeLa cells only moderately impairs clathrin-dependent trafficking. In this study, we show that HeLa cells also express auxilin 1, previously thought to be neuron specific, and that both auxilins need to be depleted for inhibition of clathrin-mediated endocytosis and intracellular sorting. Depleting both auxilins cause an approximately 50% reduction in the number of clathrin-coated pits at the plasma membrane but enhances the association of clathrin and adaptors with intracellular membranes. CCV fractions isolated from auxilin-depleted cells have an approximately 1.5-fold increase in clathrin content and more than fivefold increase in the amount of AP-2 adaptor complex and other endocytic machinery, with no concomitant increase in cargo. In addition, the structures isolated from auxilin-depleted cells are on average smaller than CCVs from control cells and are largely devoid of membrane, indicating that they are not CCVs but membraneless clathrin cages. Similar structures are observed by electron microscopy in intact auxilin-depleted HeLa cells. Together, these findings indicate that the two auxilins have overlapping functions and that they not only facilitate the uncoating of CCVs but also prevent the formation of nonproductive clathrin cages in the cytosol.

In the regulated secretory pathway, secretory granules (SGs) store peptide hormones that are released on demand. SGs are formed at the trans-Golgi network (TGN) and must undergo a maturation process to become responsive to secretagogues. The production of mature SGs requires concentrating newly synthesized soluble content proteins in granules whose membranes contain the appropriate integral membrane proteins. The mechanisms underlying the sorting of soluble and integral membrane proteins destined for SGs from other proteins are not yet well understood. For soluble proteins, luminal pH and divalent metals can affect aggregation and interaction with surrounding membranes. The trafficking of granule membrane proteins can be controlled by both luminal and cytosolic factors. Cytosolic adaptor proteins, which recognize the cytosolic domains of proteins that span the SG membrane, have been shown to play essential roles in the assembly of functional SGs. Adaptor protein 1A (AP-1A) is known to interact with specific motifs in its cargo proteins and with the clathrin heavy chain, contributing to the formation of a clathrin coat. AP-1A is present in patches on immature SG membranes, where it removes cargo and facilitates SG maturation. AP-1A recruitment to membranes can be modulated by PACS-1 (Phosphofurin Acidic Cluster Sorting protein 1), a cytosolic protein which interacts with both AP-1A and cargo that has been phosphorylated by casein kinase II. A cargo/PACS-1/AP-1A complex is necessary to drive the appropriate transport of several cargo proteins within the regulated secretory pathway. The GGA (Golgi-localized, -ear containing, ADP-ribosylation factor binding) family of adaptor proteins serve a similar role. We review the functions of AP-1A, PACS-1 and GGAs in facilitating the retrieval of proteins from immature SGs and review examples of cargo proteins whose trafficking within the regulated secretory pathway is governed by adaptor proteins.

EpsinR is a clathrin-coated vesicle (CCV) enriched 70-kD protein that binds to phosphatidylinositol-4-phosphate, clathrin, and the gamma appendage domain of the adaptor protein complex 1 (AP1). In cells, its distribution overlaps with the perinuclear pool of clathrin and AP1 adaptors. Overexpression disrupts the CCV-dependent trafficking of cathepsin D from the trans-Golgi network to lysosomes and the incorporation of mannose-6-phosphate receptors into CCVs. These biochemical and cell biological data point to a role for epsinR in AP1/clathrin budding events in the cell, just as epsin1 is involved in the budding of AP2 CCVs. Furthermore, we show that two gamma appendage domains can simultaneously bind to epsinR with affinities of 0.7 and 45 microM, respectively. Thus, potentially, two AP1 complexes can bind to one epsinR. This high affinity binding allowed us to identify a consensus binding motif of the form DFxDF, which we also find in gamma-synergin and use to predict that an uncharacterized EF-hand-containing protein will be a new gamma binding partner.

The VHS (Vps-27, Hrs and STAM) domain is a 140 residue long domain present in the very NH2-terminus of at least 60 proteins. Based on their functional characteristics and on recent data on the involvement of VHS in cargo recognition in trans-Golgi, VHS domains are considered to have a general membrane targeting/cargo recognition role in vesicular trafficking. Structurally, VHS is a right-handed superhelix of eight helices with charged surface patches probably serving as sites of protein–protein recognition and docking.