133 research outputs found
Variable Stars in the Magellanic Clouds: Results from OGLE and SIRIUS
We have performed a cross-identification between OGLE-II data and
single-epoch SIRIUS JHK survey data in the LMC and SMC. After eliminating
obvious spurious variables, we determined the pulsation periods for 9,681 and
2,927 variables in the LMC and SMC, respectively. Based on these homogeneous
data, we studied the pulsation properties and metallicity effects on period-K
magnitude (PK) relations by comparing the variable stars in the LMC and SMC.
The sample analyzed here is much larger, and we found the following new
features: (1) variable red giants in the SMC form parallel sequences on the PK
plane, just like those found by Wood (2000) in the LMC; (2) both of the
sequences A and B of Wood (2000) have discontinuities, and they occur at the
K-band luminosity of the TRGB; (3) the sequence B of Wood (2000) separates into
three independent sequences B+- and C'; (4) comparison between the theoretical
pulsation models (Wood et al. 1996) and observational data suggests that the
variable red giants on sequences C and newly discovered C' are pulsating in the
fundamental and first overtone mode, respectively; (5) the theory can not
explain the pulsation mode of sequences A+- and B+-, and they are unlikely to
be the sequences for the first and second overtone pulsators, as was previously
suggested; (6) the zero points of PK relations of Cepheids in the metal
deficient SMC are fainter than those of LMC ones by ~0.1 mag but those of SMC
Miras are brighter than those of LMC ones by ~0.13 mag, which are probably due
to metallicity effects.Comment: 9 pages, 10 figures, accepted for publication in MNRAS. High
resolution version is available at:
http://www.ioa.s.u-tokyo.ac.jp/~yita/scr/astro/papers/RefereedPaper/yitaMD250
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Interstellar Extinction Law in the J, H, and Ks Bands toward the Galactic Center
We have determined the ratios of total to selective extinction in the
near-infrared bands (J, H, Ks) toward the Galactic center from the observations
of the region |l| < 2.0deg and 0.5deg < |b| < 1.0deg with the IRSF telescope
and the SIRIUS camera. Using the positions of red clump stars in
color-magnitude diagrams as a tracer of the extinction and reddening, we
determine the average of the ratios of total to selective extinction to be
A(Ks)/E(H-Ks) = 1.44+-0.01, A(Ks)/E(J-Ks) = 0.494+-0.006, and A(H)/E(J-H) =
1.42+-0.02, which are significantly smaller than those obtained in previous
studies. From these ratios, we estimate that A(J) : A(H) : A(Ks) = 1 :
0.573+-0.009 : 0.331+-0.004 and E(J-H)/E(H-Ks) = 1.72+-0.04, and we find that
the power law A(lambda) \propto lambda^{-1.99+-0.02} is a good approximation
over these wavelengths. Moreover, we find a small variation in A(Ks)/E(H-Ks)
across our survey. This suggests that the infrared extinction law changes from
one line of sight to another, and the so-called ``universality'' does not
necessarily hold in the infrared wavelengths.Comment: 18 pages, 9 figures, Accepted for publication in the Ap
Re-Evaluation of the PBAN Receptor Molecule: Characterization of PBANR Variants Expressed in the Pheromone Glands of Moths
Sex pheromone production in most moths is initiated following pheromone biosynthesis activating neuropeptide receptor (PBANR) activation. PBANR was initially cloned from pheromone glands (PGs) of Helicoverpa zea and Bombyx mori. The B. mori PBANR is characterized by a relatively long C-terminus that is essential for ligand-induced internalization, whereas the H. zea PBANR has a shorter C-terminus that lacks features present in the B. mori PBANR critical for internalization. Multiple PBANRs have been reported to be concurrently expressed in the larval CNS of Heliothis virescens. In the current study, we sought to examine the prevalence of multiple PBANRs in the PGs of three moths and to ascertain their potential functional relevance. Multiple PBANR variants (As, A, B, and C) were cloned from the PGs of all species examined with PBANR-C the most highly expressed. Alternative splicing of the C-terminal coding sequence of the PBAN gene gives rise to the variants, which are distinguishable only by the length and composition of their respective C-terminal tails. Transient expression of fluorescent PBANR chimeras in insect cells revealed that PBANR-B and PBANR-C localized exclusively to the cell surface while PBANR-As and PBANR-A exhibited varying degrees of cytosolic localization. Similarly, only the PBANR-B and PBANR-C variants underwent ligand-induced internalization. Taken together, our results suggest that PBANR-C is the principal receptor molecule involved in PBAN signaling regardless of moth species. The high GC content of the C-terminal coding sequence in the B and C variants, which makes amplification using conventional polymerases difficult, likely accounts for previous āpreferentialā amplification of PBANR-A like receptors from other species
A Case Report of a Malignant Fibrous Histiocytoma in a T-cell Receptor Ī² Chain and p53 Double-knockout Mouse
A subcutaneous tumor was found in the right abdomen of a 16-week-old male TCRĪ² and p53
double-knockout mouse. The tumor had indistinct borders with the surrounding tissue. The
cut surface after formalin fixation was pale yellowish white, partially dark red and
partly white. Histologically, the tumor was composed of three distinct regions. The first
region showed pleomorphic cells arranged in sheets. The second region showed spindle cells
arranged in interlacing fascicles. The final region contained a mixture of the above
mentioned two types of cells. Furthermore, a small amount of collagen fibers, round cells,
multinucleated giant cells, and cells with eosinophilic granules were observed between
these tumor cells. Immunohistochemical examination and electron microscopy identified that
the pleomorphic cells and spindle cells were histiocytes and fibroblasts, respectively,
and that the round cells were undifferentiated mesenchymal cells. Based on these findings,
the tumor was diagnosed as a malignant fibrous histiocytoma
A reversible oxygen redox reaction in bulk-type all-solid-state batteries
An all-solid-state lithium battery using inorganic solid electrolytes requires safety assurance and improved energy density, both of which are issues in large-scale applications of lithium-ion batteries. Utilization of high-capacity lithium-excess electrode materials is effective for the further increase in energy density. However, they have never been applied to all-solid-state batteries. Operational difficulty of all-solid-state batteries using them generally lies in the construction of the electrode-electrolyte interface. By the amorphization of LiāRuOā as a lithium-excess model material with LiāSOā, here, we have first demonstrated a reversible oxygen redox reaction in all-solid-state batteries. Amorphous nature of the LiāRuOā-LiāSOā matrix enables inclusion of active material with high conductivity and ductility for achieving favorable interfaces with charge transfer capabilities, leading to the stable operation of all-solid-state batteries
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Pre-pregnancy BMI-specific optimal gestational weight gain for women in Japan
Background: The Institute of Medicine (IOM) guidelines are the most widely used guidelines on gestational weight gain; however, accumulation of evidence that body composition in Asians differs from other races has brought concern regarding whether their direct application is appropriate. We aimed to study to what extent optimal gestational weight gain among women in Japan differs by pre-pregnancy body mass index (BMI) and to compare estimated optimal gestational weight gain to current Japanese and Institute of Medicine (IOM) recommendations. Methods: We retrospectively studied 104,070 singleton pregnancies among nulliparous women in 2005ā2011 using the Japanese national perinatal network database. In five pre-pregnancy BMI sub-groups (17.0ā18.4, 18.5ā19.9, 20ā22.9, 23ā24.9, and 25ā27.4 kg/m2), we estimated the association of the rate of gestational weight gain with pregnancy outcomes (fetal growth, preterm delivery, and delivery complications) using multivariate regression. Results: Weight gain rate associated with the lowest risk of adverse outcomes decreased with increasing BMI (12.2 kg, 10.9 kg, 9.9 kg, 7.7 kg, and 4.3 kg/40 weeks) for the five BMI categories as described above, respectively. Current Japanese guidelines were lower than optimal gains, with the lowest risk of adverse outcomes for women with BMI below 18.5 kg/m2, and current IOM recommendations were higher than optimal gains for women with BMI over 23 kg/m2. Conclusion: Optimal weight gain during pregnancy varies largely by pre-pregnancy BMI, and defining those with BMI over 23 kg/m2 as overweight, as proposed by the World Health Organization, may be useful when applying current IOM recommendations to Japanese guidelines
Near-Infrared Imaging Polarimetry of the NGC 2071 Star Forming Region with SIRPOL
We have conducted deep JHKs imaging polarimetry of a ~8' x 8' area of the NGC
2071 star forming region. Our polarization data have revealed various infrared
reflection nebulae (IRNe) associated with the central IR young star cluster
NGC2071IR and identified their illuminating sources. There are at least 4 IRNe
in NGC2071IR and several additional IRNe are identified around nearby young
stars in the same field-of-view. Each illuminating source coincides with a
known near-IR source except for IRS3, which is only a part of IRN2 and is
illuminated by the radio source 1c. Aperture polarimetry of each cluster source
is used to detect unresolved circumstellar disk/outflow systems. Aperture
polarimetry of the other point-like sources within the field is made in this
region for the first time. The magnetic field structures (from ~1 pc down to
\~0.1 pc) are derived using both aperture polarimetry of the point-like sources
and imaging polarimetry of the shocked H2 emission that is seen as the dominant
knotty nebulae in the Ks band image; they are both of dichroic origin and the
derived field directions are consistent with each other. The magnetic field
direction projected on the sky is also consistent with that inferred from the
850 micron thermal continuum emission polarimetry of the central 0.2 pc region,
but running roughly perpendicular (~75 degrees) to the direction of the large
scale outflow. We argue that the field strength is too weak to align the
outflow in the large scale field direction via magnetic braking.Comment: o appear in PASJ, 9 pages, 11 Postscript figure
Successful Treatment of Caesarean Scar Pregnancies by Local Treatment Only
Background. Caesarean scar pregnancy (CSP) is a rare ectopic pregnancy associated with life-threatening complications. To date, no therapeutic protocols have been established. Sono-guided local methotrexate (MTX) injection is a relatively easy and low-invasive treatment. Additional systemic MTX is sometimes needed for CSP cases, especially when Ī²-subunit human chorionic gonadotropin (Ī²-hCG) levels are >20,000āmIU/ml at diagnosis. We report on six cases of CSP treated with local MTX injection, five of which received combined local treatment. Methods. Under intravenous anesthesia, six CSPs including a case with Ī²-hCG levels >20,000āmIU/ml received MTX injection to the gestational sac. Five cases received gestational sac aspiration. Three cases had additional local potassium chloride injection and one case had a saline injection aiming at the fetal heart beat concurrent with MTX injection. MTX was administered weekly if Ī²-hCG levels stayed beyond the expected values. Outcomes. All cases achieved Ī²-hCG normalization without additional systemic MTX, with one case having a successful pregnancy after treatment. Conclusion. Sono-guided local MTX injection with concurrent local treatment might be a potentially effective approach for CSP cases. The accumulation of further cases is necessary to confirm this
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