62 research outputs found
Evaluation of Euler Number of Complex Grassmann Manifold G(k, N) via Mathai-Quillen Formalism
In this paper, we provide a recipe for computing Euler number of Grassmann
manifold G(k,N) by using Mathai-Quillen formalism (MQ formalism) and
Atiyah-Jeffrey construction. Especially, we construct path-integral
representation of Euler number of G(k,N). Our model corresponds to a finite
dimensional toy-model of topological Yang-Mills theory which motivated
Atiyah-Jeffrey construction. As a by-product, we construct free fermion
realization of cohomology ring of G(k,N).Comment: 31 pages, Latex, final version accepted for publication in Journal of
Geometry and Physic
GALAXY CRUISE: Deep Insights into Interacting Galaxies in the Local Universe
We present the first results from GALAXY CRUISE, a community (or citizen)
science project based on data from the Hyper Suprime-Cam Subaru Strategic
Program (HSC-SSP). The current paradigm of galaxy evolution suggests that
galaxies grow hierarchically via mergers, but our observational understanding
of the role of mergers is still limited. The data from HSC-SSP are ideally
suited to improve our understanding with improved identifications of
interacting galaxies thanks to the superb depth and image quality of HSC-SSP.
We have launched a community science project, GALAXY CRUISE, in 2019 and
collected over 2 million independent classifications of 20,686 galaxies at z <
0.2. We first characterize the accuracy of the participants' classifications
and demonstrate that it surpasses previous studies based on shallower imaging
data. We then investigate various aspects of interacting galaxies in detail. We
show that there is a clear sign of enhanced activities of super massive black
holes and star formation in interacting galaxies compared to those in isolated
galaxies. The enhancement seems particularly strong for galaxies undergoing
violent merger. We also show that the mass growth rate inferred from our
results is roughly consistent with the observed evolution of the stellar mass
function. The 2nd season of GALAXY CRUISE is currently under way and we
conclude with future prospects. We make the morphological classification
catalog used in this paper publicly available at the GALAXY CRUISE website,
which will be particularly useful for machine-learning applications.Comment: 23 pages, 22 figures, PASJ in press. Data available at
https://galaxycruise.mtk.nao.ac.jp/en/for_researchers.htm
Dietary Lactoferrin Alleviates Age-Related Lacrimal Gland Dysfunction in Mice
BACKGROUND: Decrease in lacrimal gland secretory function is related to age-induced dry eye disease. Lactoferrin, the main glycoprotein component of tears, has multiple functions, including anti-inflammatory effects and the promotion of cell growth. We investigated how oral administration of lactoferrin affects age-related lacrimal dysfunction. METHODS AND FINDINGS: Twelve-month-old male C57BL/6Cr Slc mice were randomly divided into a control fed group and an oral lactoferrin treatment group. Tear function was measured at a 6-month time-point. After euthanasia, the lacrimal glands were subjected to histological examination with 8-hydroxy-2'-deoxyguanosine (8-OHdG) antibodies, and serum concentrations of 8-OHdG and hexanoyl-lysine adduct (HEL) were evaluated. Additionally, monocyte chemotactic protein-1(MCP-1) and tumor necrosis factor-α (TNF-α) gene expression levels were determined by real-time PCR. The volume of tear secretion was significantly larger in the treated group than in the control. Lactoferrin administration reduced inflammatory cell infiltration and the MCP-1 and TNF-α expression levels. Serum concentrations of 8-OHdG and HEL in the lactoferrin group were lower than those in the control group and were associated with attenuated 8-OHdG immunostaining of the lacrimal glands. CONCLUSION: Oral lactoferrin administration preserves lacrimal gland function in aged mice by attenuating oxidative damage and suppressing subsequent gland inflammation
The 2017 Terahertz Science and Technology Roadmap
Science and technologies based on terahertz frequency electromagnetic radiation (100GHz-30THz) have developed rapidly over the last 30 years. For most of the 20th century, terahertz radiation, then referred to as sub-millimeter wave or far-infrared radiation, was mainly utilized by astronomers and some spectroscopists. Following the development of laser based terahertz time-domain spectroscopy in the 1980s and 1990s the field of THz science and technology expanded rapidly, to the extent that it now touches many areas from fundamental science to “real world” applications. For example THz radiation is being used to optimize materials for new solar cells, and may also be a key technology for the next generation of airport security scanners. While the field was emerging it was possible to keep track of all new developments, however now the field has grown so much that it is increasingly difficult to follow the diverse range of new discoveries and applications that are appearing. At this point in time, when the field of THz science and technology is moving from an emerging to a more established and interdisciplinary field, it is apt to present a roadmap to help identify the breadth and future directions of the field. The aim of this roadmap is to present a snapshot of the present state of THz science and technology in 2016, and provide an opinion on the challenges and opportunities that the future holds. To be able to achieve this aim, we have invited a group of international experts to write 17 sections that cover most of the key areas of THz Science and Technology. We hope that The 2016 Roadmap on THz Science and Technology will prove to be a useful resource by providing a wide ranging introduction to the capabilities of THz radiation for those outside or just entering the field as well as providing perspective and breadth for those who are well established. We also feel that this review should serve as a useful guide for government and funding agencies
Representation of Geometric Objects by Path Integrals [an abstract of dissertation and a summary of dissertation review]
A cystectomic technique with low risk of rupture for women with benign ovarian cyst
The majority of patients with benign ovarian cysts undergo laparoscopic surgery using both cystectomy and stripping techniques. However, these techniques have difficulty correctly identifying cleavage planes and are prone to cyst rupture. We present a surgical cystectomy technique that correctly identifies the cleavage plane with a low risk of ovarian cyst rupture, even in patients with multicystic ovarian cysts. Cystectomy was performed using Maryland forceps with gentle open and close dissecting motions only. Both the surgeon and assistant handled the ovarian cortex and cyst wall, and soft traction between the cortex and cyst wall as far as the nearby dissection plane without grasping the cyst wall was essential. In patients with multicystic ovarian cysts, making a plane at the notch between cysts decreases the risk of cyst rupture. This technique allows the correct identification of the cleavage plane for dissection and avoids the risk of cyst rupture.Impact Statement What is already known on this subject? The majority of patients with benign ovarian cysts undergo laparoscopic surgery using both cystectomy and stripping techniques. These techniques have difficulty correctly identifying cleavage planes and are prone to cyst rupture. What do the results of this study add? This technique allows the correct identification of the cleavage plane for dissection and avoids the risk of cyst rupture. What are the implications of these findings for clinical practice and/or further research? Our technique might be useful for the preservation of the ovarian reserve because patients in this study had a low proportion of ovarian follicles in the surgical specimen
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