A highly pi-stacked organic semiconductor for field-effect transistors based on linearly condensed pentathienoacene.

We present the synthesis and characterization of a fused-ring compound, dithieno[2,3-d:2',3'-d']thieno[3,2-b:4,5-b']dithiophene (pentathienoacene, PTA). In contrast to pentacene, PTA has a larger band gap than most semiconductors used in organic field-effect transistors (OFETs) and therefore is expected to be stable in air. The large pi-conjugated and planar molecular structure of PTA would also form higher molecular orders that are conductive for carrier transport.

Thin-film transistors based on Langmuir-Blodgett films of heteroleptic bis(phthalocyaninato) rare earth complexes.

An ordered molecular assembly of heteroleptic bis(phthalocyaninato) rare earth complexes M(Pc)[Pc(OC8H17)8] [M = Tb, Lu; H2Pc = phthalocyanine; H2Pc(OC8H17)8 = 2,3,9,10,16,17,23,24-octakis(octyloxy)phthalocyanine] has been fabricated by the Langmuir-Blodgett (LB) technique and characterized by surface pressure-area isotherms, electronic absorption and polarized electronic absorption spectroscopy, low-angle X-ray diffraction, and atomic force microscopy. The molecular ordering in the LB multilayer film on SiO2 substrate was made into a p-channel field effect transistor (FET), which was generally operated in the enhanced mode. The energy levels of the highest occupied molecular orbital and the lowest unoccupied molecular orbital as well as the energy band diagram can be deduced from the electrochemical measurement results.

n-Type field-effect transistors made of an individual nitrogen-doped multiwalled carbon nanotube.

We report on the fabrication and characterization of field-effect transistor based on an individual multiwalled nitrogen-doped carbon nanotube. Our measurements show that the N-doped carbon nanotubes have n-type properties. The contact properties of the tube and Pt electrodes are also studied in detail.

Transgenic expression of a novel M. truncatula phytase gene results in improved acquisition of organic phosphorus by Arabidopsis.

A full-length cDNA encoding an extracellular form of phytase was isolated from the model legume Medicago truncatula. The phytase cDNA (MtPHY1) has an open reading frame of 1,632 bp predicted to encode 543 amino acids including an N-terminal signal peptide of 27 amino acids. The MtPHY1 gene is 5,151 bp in length, containing 7 exons and 6 introns.

Differential regulation of female rat olfactory preference and copulatory pacing by the lateral septum and medial preoptic area.

We examined the effect of bilateral radiofrequency lesions in the lateral septum (LS) or medial preoptic area (MPOA) on olfactory preference (time spent sniffing odors derived from either a stud or castrated male) and pacing behavior (paracopulatory behavior in a cage with a compartment inaccessible to males) in ovariectomized rats following different hormonal regimes. Sham-operated and LS-lesioned females, but not MPOA-lesioned females, preferred odors from the stud males to the castrated males. MPOA lesions significantly decreased total nose-poking time, compared to that of sham-operated females.

Preparation and in vitro evaluation of liposomal/niosomal delivery systems for antifungal drug clotrimazole.

Clotrimazole, an imidazole derivative antifungal agent is widely used for the treatment of mycotic infections of the genitourinary tract. In order to develop alternative formulation for the vaginal administration of clotrimazole to provide sustained and controlled release of appropriate drug for local vaginal therapy, liposomes/niosomes were evaluated as delivery vehicles. To optimize the preparation of liposomes/niosomes with regards to size and entrapment efficiency, multilamellar liposomes/niosomes containing drug were prepared by lipid hydration method.

Sex-specific effects of gonadal steroids on conspecific odor preference in the rat.

Effects of gonadal steroids on conspecific odor preference for either (1) sexually active male or active female, (2) sexually active or gonadectomized (gdx) males, (3) sexually active or gdx females, and (4) gdx males or gdx females were determined in male and female rats in a three-chamber apparatus. For the first test, gdx females were made sexually active by treatments with estradiol benzoate (EB) and progesterone (P), and sexually active males were selected by prior screening. Sexually active males and females preferred opposite-sex odor over same-sex odor.

Constituents from Polygonum cuspidatum.

Two lignan sulfates, a stilbene derivative and a phenol sulfate, together with 10 known compounds, were isolated from an aqueous extract of the root of Polygonum cuspidatum. The new compounds were elucidated based on chemical evidence and spectroscopic techniques including two-dimensional NMR methods. They exhibited no inhibition of lipid peroxidation and no cytotoxic and DNA cleavage activities.