170 research outputs found
Synthesis and circularly polarized luminescence properties of BINOL-derived bisbenzofuro[2,3-b:3′,2′-e]pyridines (BBZFPys)
A series of optically active bisbenzofuro[2,3-b:3′,2′-e]pyridine (BBZFPy) derivatives was synthesized starting with the readily available (S)- and (R)-1,1′-bi-2-naphthols through a palladium-catalyzed multiple intramolecular C-H/C-H coupling as the key ring-closure step. The effect of terminal tert-butyl substituents on the BBZFPy skeleton was systematically investigated to uncover a unique aggregation-induced enhancement of CPL characteristics in the solid state. The crystal structures of the coupling products were also evaluated by single crystal X-ray analysis and the well-ordered intermolecular stacking arrangements appeared to be responsible for the enhanced CPL.Beilstein J. Org. Chem. 2020, 16, 325–336. doi:10.3762/bjoc.16.3
Computed Tomography: Return on Investment and Regional Disparity Factor Analysis
The number of computed tomography (CT) systems in operation in Japan is approximately 4.3 times higher than that of the OECD average. However, CT systems are expensive, and thus, a heavy financial burden for hospital management. We calculate the annual net profits from CT introduction in Japan for single-slice CT (SSCT), multi-slice CT (MSCT), number of hospital beds, and prefecture. We also analyze the factors that affect CT profitability. First, the annual income per CT in operation is estimated for 2011. Second, the annual costs per CT are calculated as the sum of depreciation, maintenance, and labor costs. Finally, the annual net profits per CT are estimated for SSCT and MSCT, the number of hospital beds, and prefecture. A correlation analysis between the annual net profits, population, and number of physicians per CT equipment is used to determine the determinants of the net CT profits by prefecture. Our results show that, for hospitals with fewer than 100 beds, the annual net CT profits are higher for SSCT than MSCT, and vice versa for hospitals with at least 100 beds. Both SSCT and MSCT increased profits as the number of hospital beds increased. The annual net CT profits per prefecture are USD −12,105 for SSCT and USD 87,233 for MSCT, on average. The annual net profits per prefecture and population per CT show positive correlations with both SSCT and MSCT, as do the annual net profits per prefecture and number of physicians per CT. Thus, choosing high-performance MSCT is advantageous in terms of profitability in facilities with at least 100 beds. Additionally, CT profitability presumably affects the balance between the number of introduced CTs, population per CT, and number of physicians per CT
Pilot VLBI Survey of SiO v=3 J=1--0 Maser Emission around Evolved Stars
In this Letter, we report detections of SiO v=3 J=1--0 maser emission in very
long baseline interferometric (VLBI) observations towards 4 out of 12
long-period variable stars: WX Psc, R Leo, W Hya, and T Cep. The detections
towards WX Psc and T Cep are new ones. We also present successful astrometric
observations of SiO v=2 and v=3 J=1--0 maser emissions associated with two
stars: WX Psc and W Hya and their position-reference continuum sources:
J010746.0+131205 and J135146.8-291218 with the VLBI Exploration of Radio
Astrometry (VERA). The relative coordinates of the position-reference continuum
source and SiO v=3 maser spots were measured with respect to those of an SiO
v=2 maser spot adopted as fringe-phase reference. Thus the faint continuum
sources were inversely phase-referenced to the bright maser sources. It implies
possible registration of multiple SiO maser line maps onto a common coordinate
system with 10 microarcsecond-level accuracy.Comment: 5 Pages, 3 figures, Fig.3 and Tab. 2 were corrected; Publications of
the Astronomical Society of Japan, Vol. 64, No. 6 issued on 2012 December 2
<Abstract of Published Report>Development of Agglomerated Crystals of Ascorbic Acid for Direct Tableting by Spherical Crystallization Technique and Evaluation of Their Compactibilities.
Astrometry of Water Maser Sources in Nearby Molecular Clouds with VERA - II. SVS 13 in NGC 1333
We report on the results of multi-epoch VLBI observations with VERA (VLBI
Exploration of Radio Astrometry) of the 22 GHz H2O masers associated with the
young stellar object SVS 13 in the NGC 1333 region. We have carried out
phase-referencing VLBI astrometry and measured an annual parallax of the maser
features in SVS 13 of 4.25+/-0.32 mas, corresponding to the distance of
235+/-18 pc from the Sun. Our result is consistent with a photometric distance
of 220 pc previously reported. Even though the maser features were detectable
only for 6 months, the present results provide the distance to NGC 1333 with
much higher accuracy than photometric methods. The absolute positions and
proper motions have been derived, revealing that the H2O masers with the LSR
(local standard of rest) velocities of 7-8 km s-1 are most likely associated
with VLA4A, which is a radio counterpart of SVS 13. The origin of the observed
proper motions of the maser features are currently difficult to attribute to
either the jet or the rotating circumstellar disk associated with VLA4A, which
should be investigated through future high-resolution astrometric observations
of VLA4A and other radio sources in NGC 1333.Comment: 9 pages, 5 figures. PASJ, in press (2008, Vol. 60, No. 1
Identification and characterization of an oocyte factor required for development of porcine nuclear transfer embryos.
Nuclear reprogramming of differentiated cells can be induced by oocyte factors. Despite numerous attempts, these factors and mechanisms responsible for successful reprogramming remain elusive. Here, we identify one such factor, necessary for the development of nuclear transfer embryos, using porcine oocyte extracts in which some reprogramming events are recapitulated. After incubating somatic nuclei in oocyte extracts from the metaphase II stage, the oocyte proteins that were specifically and abundantly incorporated into the nuclei were identified by mass spectrometry. Among 25 identified proteins, we especially focused on a multifunctional protein, DJ-1. DJ-1 is present at a high concentration in oocytes from the germinal vesicle stage until embryos at the four-cell stage. Inhibition of DJ-1 function compromises the development of nuclear transfer embryos but not that of fertilized embryos. Microarray analysis of nuclear transfer embryos in which DJ-1 function is inhibited shows perturbed expression of P53 pathway components. In addition, embryonic arrest of nuclear transfer embryos injected with anti-DJ-1 antibody is rescued by P53 inhibition. We conclude that DJ-1 is an oocyte factor that is required for development of nuclear transfer embryos. This study presents a means for identifying natural reprogramming factors in mammalian oocytes and a unique insight into the mechanisms underlying reprogramming by nuclear transfer
Astrometry of Galactic Star Forming Region Sharpless 269 with VERA : Parallax Measurements and Constraint on Outer Rotation Curve
We have performed high-precision astrometry of H2O maser sources in Galactic
star forming region Sharpless 269 (S269) with VERA. We have successfully
detected a trigonometric parallax of 189+/-8 micro-arcsec, corresponding to the
source distance of 5.28 +0.24/-0.22 kpc. This is the smallest parallax ever
measured, and the first one detected beyond 5 kpc. The source distance as well
as proper motions are used to constrain the outer rotation curve of the Galaxy,
demonstrating that the difference of rotation velocities at the Sun and at S269
(which is 13.1 kpc away from the Galaxy's center) is less than 3%. This gives
the strongest constraint on the flatness of the outer rotation curve and
provides a direct confirmation on the existence of large amount of dark matter
in the Galaxy's outer disk.Comment: 7 pages and 4 figures, Accepted by PASJ (Vol. 59, No. 5, October 25,
2007 issue
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