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The first chordates appeared over a half a billion years ago, providing the ancestral stock from which modern vertebrates emerged. To shed some light on the chordate origins, we have sequenced the genome of Ciona intestinalis, a sea squirt whose lineage split from that of vertebrates in the mid Cambrian. Ciona has long been a popular model system for the study of development, featuring world-wide and year-round availability, easily visualized cells and morphogenetic processes, simple methods for transient transgene expression, and a growing genomic infrastructure including extensive EST and cDNA collections. A comparison of the assembled Ciona genome sequence and gene complement with available invertebrate and vertebrate sequences provides insight into the origins and development of a chordate and vertebrate systems including the nervous systems, muscular, immune and endocrine systems, as well as the evolution of the chordate body plan. The Ciona genome provides a foundation for a genome-scale analyses of regulatory networks through chordate development.

Abstract Objective: To evaluate the effects of Hochuekkito, a traditional Japanese and Chinese medicine, in the treatment of elderly patients with general weakness. To devise a suitable study design for [...]

A down-scattered neutron detector operating in the multichannel counting mode was developed for areal density (ρR) measurement. Equipped with a newly developed 6Li glass scintillator (APLF80), the detector was tested in a fusion experiment at the GEKKO XII facility, Osaka University, Osaka, Japan. For a low-ρR fusion shot, the detector clearly discriminated the γ-rays, primary neutrons, γ-rays produced via (n, γ) reactions from the target chamber, and neutrons scattered by the target chamber. Furthermore, the observed signal was in good agreement with predictions made by Monte Carlo simulation.

A new high resolution positron emission tomography (PET) system dedicated to in vivo animal studies has been developed. A block detector, which is a position-sensistive photomultiplier tube (Hamamatsu R3941-02) coupled to 4 arrays of 1.7 mm wide BGO crystals has been adopted to the system. There are 15 block detectors positioned to form a 35 em diameter ring, with the coupling of 4 BGO arrays to each PMT. This provides 4 detector rings, giving the system a 7 slice imaging capability. The gantry head tilts up to [+ or - ]90 [degrees], and is capable of moving up and down by 30 cm. These positioning capabilities allow flexibility and great ease of use in subject positioning. Also, a gantry entrance size of 22 cm in diameter allows studies ranging from rats and mice to primates such as Rhesus and squirrel monkeys. The physical performance of the system has been evaluated. The spatial resolution in the center of the field of view (FOV) is 3.0 mm at full width at half maximum (FWHM) in the transaxial plane. The axial resolution at the center of the FOV is 4.8 mm FWHM in the direct plane, and 4.1 mm FWHM in the cross plane. The total system sensitivity is 20.7 kcps/[mu]Ci/ml for a 10 cm diameter cylindrical uniform phantom with an energy threshold of 300 keV.