Chemical ordering beyond the superstructure in long-range ordered systems

To describe chemical ordering in solid solutions systems Warren-Cowley short-range parameters are ordinarily used. However, they are not directly suited for application to long-range ordered systems, as they do not converge to zero for large separations. It is the aim of this paper to generalize the theory to long-range ordered systems and quantitatively discuss chemical short-range order beyond the superstructure arrangements. This is demonstrated on the example of a non-stoichiometric B2-ordered intermetallic alloy. Parameters of interatomic potentials are taken from an embedded atom method (EAM) calculations and the degree of order is simulated by the Monte Carlo method. Both on-lattice and off-lattice methods, where the latter allows individual atoms to deviate from their regular lattice sites, were used, and the resulting effects are discussed

Planting the Chalcone Reductase Family Tree: Identification and Characterization of Chalcone Reductase Genes in Soybean

Soybean (Glycine max [L.] Merr) is an important crop grown in Canada, generating $2.4 billion in sales. Though this number may be promising, soybean farmers lose about$50 million worth of yield annually due to root and stem rot disease caused by Phytophthora sojae. Many strategies have been developed to combat the infection; however, these methods are prohibitively expensive. A ‘cost effective’ approach to this problem is to select a trait naturally found in soybean that can increase resistance. One such trait is the increased production of root glyceollins. One of the key enzymes exclusively involved in glyceollin synthesis is chalcone reductase (CHR). To identify all GmCHR gene family members in the soybean genome, a search was conducted in Phytozome which revealed 16 putative GmCHRs. Among these, 7 GmCHRs were selected for further study as they contain all active site residues, and are transcribed. All candidate GmCHRs localize to both the nucleus and cytoplasm. Amongst the candidate GmCHRs, there are four root-specific GmCHRs which are induced upon stress. In addition, three QTLs have been found which contain GmCHR loci. Overall, these findings suggest that chalcone reductase is an important component in manipulating glyceollin content and could eventually be used to improve resistance against P. sojae

High-fidelity quantum logic gates using trapped-ion hyperfine qubits

We demonstrate laser-driven two-qubit and single-qubit logic gates with fidelities 99.9(1)% and 99.9934(3)% respectively, significantly above the approximately 99% minimum threshold level required for fault-tolerant quantum computation, using qubits stored in hyperfine ground states of calcium-43 ions held in a room-temperature trap. We study the speed/fidelity trade-off for the two-qubit gate, for gate times between 3.8$\mu$s and 520$\mu$s, and develop a theoretical error model which is consistent with the data and which allows us to identify the principal technical sources of infidelity.Comment: 1 trap, 2 ions, 3 nines. Detailed write-up of arXiv:1406.5473 including single-qubit gate data als

High-fidelity trapped-ion quantum logic using near-field microwaves

We demonstrate a two-qubit logic gate driven by near-field microwaves in a room-temperature microfabricated ion trap. We measure a gate fidelity of 99.7(1)\%, which is above the minimum threshold required for fault-tolerant quantum computing. The gate is applied directly to $^{43}$Ca$^+$ "atomic clock" qubits (coherence time $T_2^*\approx 50\,\mathrm{s}$) using the microwave magnetic field gradient produced by a trap electrode. We introduce a dynamically-decoupled gate method, which stabilizes the qubits against fluctuating a.c.\ Zeeman shifts and avoids the need to null the microwave field

(2E,4E)-N-Benzyl-2-cyano-5-phenyl­penta-2,4-dienamide

In the title compound, C19H16N2O, the mol­ecule adopts an E configuration about the two C=C double bonds. The dihedral angle between the phenyl rings is 88.89 (8)°. In the crystal, mol­ecules are linked by inter­molecular N—H⋯N and C—H⋯O hydrogen bonds into chains running parallel to [130]

2-[(E)-4-(2-Bromo­phen­yl)but-3-en-2-yl­idene]malononitrile

The title compound, C13H19BrN2, is planar structure except for the methyl H atoms, the maximum atomic deviation for the non-H atoms being 0.100 (1) Å. The bromo­phenyl and isopropanylidenemalononitrile units are located on opposite sides of the C=C bond, showing an E configuration

(E)-2-[1-(4-Fluoro­phen­yl)pent-1-en-3-yl­idene]malononitrile

The title mol­ecule, C14H11FN2, is approximately planar except the ethyl group, the maximum atomic deviation being 0.105 (5) Å. The fluoro­phenyl ring and 2-propyl­idene­malononitrile unit are located on the opposite sides of the C=C double bond, showing an E configuration