Tailoring the photovoltaic effect in (1 1 1) oriented BiFeO3/LaFeO3 superlattices.

Ferroelectric and photovoltaic properties of (BiFeO3)(1-x)Λ/(LaFeO3) xΛ superlattices grown by pulsed laser deposition have been investigated (Λ being the bilayer thickness). For a high concentration of BiFeO3 a ferroelectric state is observed simultaneously with a switchable photovoltaic response. In contrast for certain concentration of LaFeO3 a non-switchable photovoltaic effect is evidenced. Such modulation of the PV response in the superlattices is attributed to the ferroelectric to paraelectric phase transition which is controlled with the increase of x. Remarkably, concomitant to this change of PV mechanism, a change of the conduction mechanism also seems to take place from a bulk-limited to an interface-limited transport as x increases.

Enhanced adenoviral-vector mediated gene transfer using human albumin solder.

BACKGROUND AND OBJECTIVE: Laser tissue welding with human albumin solder (HAS) has been used as an alternative method of wound closure. Adenoviral vectors have been used to introduce various cytokine genes into wounds to accelerate wound closure. In the present study, we were interested in the effect of HAS on adenoviral vector transfer of the beta-galactosidase (beta-gal) gene in vitro and in vivo. STUDY DESIGN/MATERIALS AND METHODS: 3T3 fibroblasts were used to study the effect of HAS on beta-gal gene transfer in vitro. The presence of beta-gal was determined by Western blot, and its activity by a colorimetric assay. A punch biopsy model of wound healing in pigs was used for in vivo experiments. RESULTS: HAS increased the efficiency of adenoviral-mediated beta-gal transduction and stabilized the adenovirus at room temperature. HAS protected adenovirus from inactivation by laser, both in vitro and in vivo. CONCLUSIONS: HAS may stabilize adenoviral vectors to deliver cytokine genes in future wound healing experiments.

The venomous hair structure, venom and life cycle of Lagoa crispata, a puss caterpillar of Oklahoma.

The presence of a unique population of Lagoa crispata, puss caterpillar, in western Oklahoma is reported. A detailed microscopic examination shows the structure of the L. crispata spines resemble the type 4 spines described by [Kawamoto, F., Kumada, N., 1984. Biology and venoms of lepidoptera. In: Tu, A.T. (Ed.), Handbook of Natural Toxins, Insect Poisons, Allergens and other invertebrate venoms, vol. 2, pp. 291-332 (ch. 9)]. The major food source of L. crispata are the leaves of oak (shin oak). The high tannin content of this food source results in spine extracts high in oak tannins. These extracts have activity but enzyme and toxin activity is lost with time. The gel filtration protein fractions are colored from brown to yellow and are inactive as enzymes or toxins. No hyaluronidase, protease or phosphohydrolase activity is detected in these protein fractions. The life cycle shows these caterpillars have 6 instars. Characterizations and annual emerging times of each instar are included.