1,222 research outputs found
Correction of near-infrared high-resolution spectra for telluric absorption at 0.90-1.35 microns
We report a method of correcting a near-infrared (0.90-1.35 m)
high-resolution () spectrum for telluric
absorption using the corresponding spectrum of a telluric standard star. The
proposed method uses an A0\,V star or its analog as a standard star from which
on the order of 100 intrinsic stellar lines are carefully removed with the help
of a reference synthetic telluric spectrum. We find that this method can also
be applied to feature-rich objects having spectra with heavily blended
intrinsic stellar and telluric lines and present an application to a G-type
giant using this approach. We also develop a new diagnostic method for
evaluating the accuracy of telluric correction and use it to demonstrate that
our method achieves an accuracy better than 2\% for spectral parts for which
the atmospheric transmittance is as low as 20\% if telluric standard
stars are observed under the following conditions: (1) the difference in
airmass between the target and the standard is ; and (2) that in
time is less than 1 h. In particular, the time variability of water vapor has a
large impact on the accuracy of telluric correction and minimizing the
difference in time from that of the telluric standard star is important
especially in near-infrared high-resolution spectroscopic observation.Comment: 20 pages, 16 figures, accepted for publication in Publications of the
Astronomical Society of the Pacifi
Global Structure of Moduli Space for BPS Walls
We study the global structure of the moduli space of BPS walls in the Higgs
branch of supersymmetric theories with eight supercharges. We examine the
structure in the neighborhood of a special Lagrangian submanifold M, and find
that the dimension of the moduli space can be larger than that naively
suggested by the index theorem, contrary to previous examples of BPS solitons.
We investigate BPS wall solutions in an explicit example of M using Abelian
gauge theory. Its Higgs branch turns out to contain several special Lagrangian
submanifolds including M. We show that the total moduli space of BPS walls is
the union of these submanifolds. We also find interesting dynamics between BPS
walls as a byproduct of the analysis. Namely, mutual repulsion and attraction
between BPS walls sometimes forbid a movement of a wall and lock it in a
certain position; we also find that a pair of walls can transmute to another
pair of walls with different tension after they pass through.Comment: 42 pages, 11 figures; a few comments adde
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Increased tissue levels of omega-3 polyunsaturated fatty acids prevents pathological preterm birth
Omega-3 polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) have anti-inflammatory effects. Preterm birth is an important problem in modern obstetrics and one of the main causes is an inflammation. We here showed that abundance of omega-3 fatty acids reduced the incidence of preterm birth induced by LPS with fat-1 mice, capable of converting omega-6 to omega-3 fatty acids. We also indicated that the gene expression of IL-6 and IL-1β in uteruses and the number of cervical infiltrating macrophages were reduced in fat-1 mice. The analyses of lipid metabolomics showed the high level of 18-hydroxyeicosapentaenoate in fat-1 mice, which was derived from EPA and was metabolized to anti-inflammatory product named resolvin E3 (RvE3). We finally showed that the administration of RvE3 to LPS-exposed pregnant wild type mice lowered the incidence of preterm birth. Our data suggest that RvE3 could be a potential new therapeutic for the prevention of preterm birth
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Omega-3 Polyunsaturated Fatty Acids Suppress the Cystic Lesion Formation of Peritoneal Endometriosis in Transgenic Mouse Models
Omega-3 polyunsaturated fatty acids (omega-3 PUFAs) play a role in controlling pathological inflammatory reactions. Endometriosis is characterized by the presence of endometrial tissue on the peritoneum and an exaggerated inflammatory environment around ectopic tissues. Here peritoneal endometriosis was reproduced using a mouse model in which murine endometrial fragments were inoculated into the peritoneal cavity of mice. Fat-1 mice, in which omega-6 can be converted to omega-3 PUFAs, or wild type mice, in which it cannot, were used for the endometriosis model to address the actions of omega-3 PUFAs on the development of endometriotic lesions. The number and weight of cystic endometriotic lesions in fat-1 mice two weeks after inoculation were significantly less than half to those of controls. Mediator lipidomics revealed that cystic endometriotic lesions and peritoneal fluids were abundant in 12/15-hydroxyeicosapentaenoic acid (12/15-HEPE), derived from eicosapentaenoic acid (EPA), and their amount in fat-1 mice was significantly larger than that in controls. 12/15-Lipoxygenase (12/15-LOX)-knockout (KO) and control mice with or without EPA administration were assessed for the endometriosis model. EPA administration decreased the number of lesions in controls but not in 12/15-LOX-KO mice. The peritoneal fluids in EPA-fed 12/15-LOX-KO mice contained reduced levels of EPA metabolites such as 12/15-HEPE and EPA-derived resolvin E3 even after EPA administration. cDNA microarrays of endometriotic lesions revealed that Interleukin-6 (IL-6) expression in fat-1 mice was significantly lower than that in controls. These results suggest that both endogenous and exogenous EPA-derived PUFAs protect against the development of endometriosis through their anti-inflammatory effects and, in particular, the 12/15-LOX-pathway products of EPA may be key mediators to suppress endometriosis
Change in ground reaction force parameters according to the frailty level of older women in the Timed Up and Go test
As older people become frail, they tend to fall more easily. Moreover, women have a higher rate of falls than men. However, effective strategies to avoid elderly women falling are lacking. The Timed Up and Go test is a well-known indicator of falling tendency. This study clarifies the motor elements related to the Timed Up and Go test according to the degree of weakness in older outpatients to specify exercise intervention to improve weakness and prevent falls. Participants were 145 female outpatients who visited the Locomo-Frail outpatient clinic, classified into three groups (robust, prefrail, and frail, according to the definition of the Japanese Cardiovascular Health Study. Vertical ground reaction force parameters were measured for all participants when they stood up from a chair, walking speed, and the Timed Up and Go test. Results showed that walking speed is related to the Timed Up and Go test in the robust group; balance ability is related to the Timed Up and Go test in the prefrail group; and instantaneous force is related to the Timed Up and Go test in the frail group. These results suggest that weakness can be improved by performing exercise interventions of balance and instantaneous force elements in the prefrail and frail groups, respectively.departmental bulletin pape
Selection of lactic yeast producing glucosylceramide from cheese whey
application/pdfFrom 2150 isolates from raw milk and milk products, yeast strains were surveyed to produce glucosylceramide from cheese whey. Most of the 54 strains that had accumulated a detectable amount of glucosylceramide were identified as Kluyveromyces lactis var. lactis. The cells of K. lactis var. lactis strain M-11 derived from domestic raw milk accumulated glucosylceramide 2.5-fold higher than K. lactis var. lactis NBRC 1267, the reference strain selected from the culture collections. Strain M-16 of K. lactis var. lactis derived from the same origin was found to synthesize a considerable amount of steryl glucoside in addition to glucosylceramide. Sequence analysis of ribosomal DNA intergenic spacer two regions revealed that strains M-11 and M-16 were diverged from a type strain of K. lactis var. lactis in the same species.journal articl
A novel mechanism of myocyte degeneration involving the Ca2+-permeable growth factor–regulated channel
Disruption of the dystrophin–glycoprotein complex caused by genetic defects of dystrophin or sarcoglycans results in muscular dystrophy and/or cardiomyopathy in humans and animal models. However, the key early molecular events leading to myocyte degeneration remain elusive. Here, we observed that the growth factor–regulated channel (GRC), which belongs to the transient receptor potential channel family, is elevated in the sarcolemma of skeletal and/or cardiac muscle in dystrophic human patients and animal models deficient in dystrophin or δ-sarcoglycan. However, total cell GRC does not differ markedly between normal and dystrophic muscles. Analysis of the properties of myotubes prepared from δ-sarcoglycan–deficient BIO14.6 hamsters revealed that GRC is activated in response to myocyte stretch and is responsible for enhanced Ca2+ influx and resultant cell damage as measured by creatine phosphokinase efflux. We found that cell stretch increases GRC translocation to the sarcolemma, which requires entry of external Ca2+. Consistent with these findings, cardiac-specific expression of GRC in a transgenic mouse model produced cardiomyopathy due to Ca2+ overloading, with disease expression roughly parallel to sarcolemmal GRC levels. The results suggest that GRC is a key player in the pathogenesis of myocyte degeneration caused by dystrophin–glycoprotein complex disruption
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