136 research outputs found
Development And Characterization Of 27 Microsatellite Markers For The Mangrove Fern, Acrostichum Aureum (pteridaceae)
Premise of the study: Twenty-seven nuclear microsatellite markers were developed for the mangrove fern, Acrostichum aureum (Pteridaceae), to investigate the genetic structure and demographic history of the only pantropical mangrove plant. Methods and Results: Fifty-six A. aureum individuals from three populations were sampled and genotyped to characterize the 27 loci. The number of alleles and expected heterozygosity ranged from one to 15 and 0.000 to 0.893, respectively. Across the 26 polymorphic loci, the Malaysian population showed much higher levels of polymorphism compared to the other two populations in Guam and Brazil. Cross-amplification tests in the other two species from the genus determined that seven and six loci were amplifiable in A. danaeifolium and A. speciosum, respectively. Conclusions: The 26 polymorphic microsatellite markers will be useful for future studies investigating the genetic structure and demographic history of of A. aureum, which has the widest distributional range of all mangrove plants.49Japan Society for the Promotion of Science (JSPS) [KAKENHI 22405005, 25290080]JSPS Invitation Program for East Asian Young Researchers (JENESYS) ProgramMinistry of Education, Culture, Sports, Science, and Technology TOBITATE! Young Ambassador ProgramChiba University International Exchange Progra
Virtual Human Generative Model: Masked Modeling Approach for Learning Human Characteristics
Identifying the relationship between healthcare attributes, lifestyles, and
personality is vital for understanding and improving physical and mental
conditions. Machine learning approaches are promising for modeling their
relationships and offering actionable suggestions. In this paper, we propose
Virtual Human Generative Model (VHGM), a machine learning model for estimating
attributes about healthcare, lifestyles, and personalities. VHGM is a deep
generative model trained with masked modeling to learn the joint distribution
of attributes conditioned on known ones. Using heterogeneous tabular datasets,
VHGM learns more than 1,800 attributes efficiently. We numerically evaluate the
performance of VHGM and its training techniques. As a proof-of-concept of VHGM,
we present several applications demonstrating user scenarios, such as virtual
measurements of healthcare attributes and hypothesis verifications of
lifestyles.Comment: 14 pages, 4 figure
Distance to Orion KL Measured with VERA
We present the initial results of multi-epoch VLBI observations of the 22 GHz
H2O masers in the Orion KL region with VERA (VLBI Exploration of Radio
Astrometry). With the VERA dual-beam receiving system, we have carried out
phase-referencing VLBI astrometry and successfully detected an annual parallax
of Orion KL to be 2.29+/-0.10 mas, corresponding to the distance of 437+/-19 pc
from the Sun. The distance to Orion KL is determined for the first time with
the annual parallax method in these observations. Although this value is
consistent with that of the previously reported, 480+/-80 pc, which is
estimated from the statistical parallax method using proper motions and radial
velocities of the H2O maser features, our new results provide the much more
accurate value with an uncertainty of only 4%. In addition to the annual
parallax, we have detected an absolute proper motion of the maser feature,
suggesting an outflow motion powered by the radio source I along with the
systematic motion of source I itself.Comment: 7 pages, 3 figures. PASJ, in press (Vol. 59, No. 5, October 25, 2007
issue
Absolute Proper Motions of H2O Masers Away from the Galactic Plane Measured with VERA in the "Superbubble" Region NGC 281
We report on absolute proper-motion measurements of an H2O maser source in
the NGC 281 West molecular cloud, which is located ~320 pc above the Galactic
plane and is associated with an HI loop extending from the Galactic plane. We
have conducted multi-epoch phase-referencing observations of the maser source
with VERA (VLBI Exploration of Radio Astrometry) over a monitoring period of 6
months since May 2006. We find that the H2O maser features in NGC 281 West are
systematically moving toward the southwest and further away from the Galactic
plane with a vertical velocity of ~20-30 km/s at its estimated distance of
2.2-3.5 kpc. Our new results provide the most direct evidence that the gas in
the NGC 281 region on the HI loop was blown out from the Galactic plane, most
likely in a superbubble driven by multiple or sequential supernova explosions
in the Galactic plane.Comment: 10 pages, 5 figures, PASJ in press (Vol. 59, No. 4; August 25, 2007
issue
VLBI Astrometry of AGB Variables with VERA -- A Semiregular Variable S Crateris --
We present a distance measurement for the semiregular variable S Crateris (S
Crt) based on its annual parallax. With the unique dual beam system of the VLBI
Exploration for Radio Astrometry (VERA) telescopes, we measured the absolute
proper motion of a water maser spot associated with S Crt, referred to the
quasar J1147-0724 located at an angular separation of 1.23. In
observations spanning nearly two years, we have detected the maser spot at the
LSR velocity of 34.7 km s, for which we measured the annual parallax of
2.330.13 mas corresponding to a distance of 430 pc. This
measurement has an accuracy one order of magnitude better than the parallax
measurements of HIPPARCOS. The angular distribution and three-dimensional
velocity field of maser spots indicate a bipolar outflow with the flow axis
along northeast-southwest direction. Using the distance and photospheric
temperature, we estimate the stellar radius of S Crt and compare it with those
of Mira variables.Comment: 9 pages, 4 figures, accepted for publication in PASJ (Vol.60, No.5,
October 25, VERA special issue
Fiber-comb-stabilized light source at 556 nm for magneto-optical trapping of ytterbium
A frequency-stabilized light source emitting at 556 nm is realized by
frequency-doubling a 1112-nm laser, which is phase-locked to a fiber-based
optical frequency comb. The 1112-nm laser is either an ytterbium (Yb)-doped
distributed feedback fiber laser or a master-slave laser system that uses an
external cavity diode laser as a master laser. We have achieved the continuous
frequency stabilization of the light source over a five-day period. With the
light source, we have completed the second-stage magneto-optical trapping (MOT)
of Yb atoms using the 1S0 - 3P1 intercombination transition. The temperature of
the ultracold atoms in the MOT was 40 uK when measured using the time-of-flight
method, and this is sufficient for loading the atoms into an optical lattice.
The fiber-based frequency comb is shown to be a useful tool for controlling the
laser frequency in cold-atom experiments.Comment: 18 pages, 6 figures, submitted to and accepted by J. Opt. Soc. Am. B
(ID 125081
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