Doped LaGa03 exhibits high oxide ionic conductivity. Doping of Sr for the La site and Mg for the Ga site is the most effective method for enhancing the oxide ionic conductivity of LaGa03. The oxide ionic conductivity of Lao.9Sro.1Gao.8Mgo.2O3 was higher than that of Sc-doped Zr02 and slightly lower than that of Bi203 oxide. Furthermore, electronic or hole conduction was negligibly small in the oxygen partial pressure region from 1 to 10-20 atm.

We report here that hydroxyphosphine ligands (PO ligands) significantly accelerate nickel-catalyzed cross-coupling reactions of unreactive aryl electrophiles and Grignard reagents. The new catalytic system based on the nickel-PO-Grignard combination allows facile activation of unreactive aryl halides such as fluorides, chlorides, polyfluorides, and polychlorides as well as phenol derivatives such as carbamates and phosphates to give the corresponding cross-coupling products in good to excellent yields. We ascribe the high catalytic activity to a nickel phosphine/magnesium alkoxide bimetallic species that forms from the nickel precatalyst, the PO ligand, and the Grignard reagent and undergoes activation of the aryl-X bond by a cooperative push-pull action of the nucleophilic nickel and Lewis acidic magnesium centers. This mechanistic conjecture was corroborated by kinetic isotope effect experiments and density functional theory calculations. Being distinct from the conventional three-centered mechanism for oxidative addition, the proposed mechanism for the C-X bond activation offers a new concept for the design of cross-coupling reactions as well as other homogeneous catalyses involving activation of electrophilic substrates.

Behavior such as ontogenetic vertical migration (OVM) limits the transport of marine larvae with short pelagic larval durations (PLDs), but its effect on the supposed long-distance dispersal of larvae with long PLDs is unknown. We conducted laboratory tests of ontogenetic change in larval phototaxis and examined size-specific patterns of larval distribution in the plankton to characterize OVM in the Caribbean spiny lobster Panulirus argus during its long (6 mo) PLD. We then used a coupled biophysical model to explore the consequences of OVM and hydrodynamics on larval P. argus dispersal in the Caribbean Sea. Larvae reared in the laboratory were positively phototatic for the first 2 mo and then avoided light thereafter, similar that seen in the planktonic distribution of same-sized larvae. Simulations of larval dispersal from 13 spawning sites in the Caribbean Sea predicted that twice as many larvae would recruit to nurseries if they displayed OVM compared with passive dispersers. Larvae with OVM typically settled < 400 km from where they were spawned, while passive dispersers often settled >1000 km away. OVM also produced an asymmetrical bimodal pattern of dispersal dominated by larvae that settled near their origin (~60%), but showed a second peak of larvae that dispersed over long distances (~20%). Hydrodynamics created subregional differences in the potential for self-recruitment. Our findings suggest that (1) larval behavior constrains the dispersal of even long-lived larvae, particularly in tandem with retentive oceanographic environments, and (2) larval sources of P. argus in the Caribbean Sea cannot be estimated from passive transport and surface circulation.

Anti-allergic effects (types I and IV) of the 70% ethanol extract (CM-ext) obtained from Cnidii Monnieri Fructus (dried fruits of Cnidium monnieri) were investigated on 48 h homologous passive cutaneous anaphylaxis (PCA), 2, 4-dinitrofluorobenzene (DNFB)-induced contact dermatitis and picryl chloride (PC)-induced contact dermatitis in experimental animals. CM-ext showed inhibitory effects on these allergic models. Osthol isolated from CM-ext also had the inhibitory effects. These results suggested that Cnidii Monnieri Fructus might be useful as an agent for allergic diseases and that its anti-allergic effect was partially attributable to a coumarin derivative, osthol.

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