Probing Chemical Enrichment in Extremely Metal-Poor Galaxies and First Galaxies

The chemical composition of galaxies offers vital insights into their formation and evolution. A key aspect of this study is the correlation between helium abundance (He/H) and metallicity, which is instrumental in estimating the primordial helium generated by Big Bang nucleosynthesis. We study the chemical enrichment history of low-metallicity galaxies, specifically focusing on extremely metal-poor galaxies (EMPGs) and the first galaxies, using the one-zone model and cosmological hydrodynamic simulations. Our one-zone model, using the Limongi & Chieffi (2018) yield, aligns well with observed high He/H ratios at low metallicities and reproduces Fe/O ratios akin to EMPGs. Conversely, the Nomoto et al. (2013) yield does not fully match the high Fe/O ratios seen in EMPGs. Our cosmological hydrodynamic simulations of the first galaxy successfully replicate the stellar mass and star formation rate of galaxies like GN-z11 but fail to produce metallicity and high He/H at low O/H. This is consistent with the results of the one-zone model, which shows that the slope of the He/H-O/H relation is moderate in young, actively star-forming galaxies, suggesting the importance of using galaxies with similar star formation histories for the fit. These results highlight the need for high-resolution simulations and expanded observational datasets to refine our understanding of early galactic chemical evolution.Comment: 14 pages, 7 figures, 1 table, submitted to Ap

An Awareness of Japanese Crew in the EMS Helicopter on Organizational Management

Abstract. Kushiro city general hospital and Kojinkai Memorial Hospital started EMS Project on 5 October 2009. It had worked 14 times on 26 November, and save a lot of lives. The EMS helicopter plays an important role of regional differences in medication. The EMS operates three institutions -an Aviation Organization, a Medical Organization and a Fire Organization. However, the cooperation of labor doesn't happen in their division of labors. It does not make divide the work. This is because the EMS does not divide work and responsibilities clearly one solution is to have a common field of responsibility across the 3 organization order to improve cooperation. Since this study analyzes the EMS organization from the knowledge creation point of view. This paper is based on a month-long research study at hospital waiting rooms

CDDP-induced desmoplasia-like changes in oral cancer tissues are related to SASP-related factors induced by the senescence of cancer cells

Nishimura J., Morita Y., Tobe-Nishimoto A., et al. CDDP-induced desmoplasia-like changes in oral cancer tissues are related to SASP-related factors induced by the senescence of cancer cells. International Immunopharmacology 136, 112377 (2024); https://doi.org/10.1016/j.intimp.2024.112377.The tumor microenvironment (TME) concept has been proposed and is currently being actively studied. The development of extracellular matrix (ECM) in the TME is known as desmoplasia and is observed in many solid tumors. It has also been strongly associated with poor prognosis and resistance to drug therapy. Recently, cellular senescence has gained attention as an effect of drug therapy on cancer cells. Cellular senescence is a phenomenon wherein proliferating cells become resistant to growth-promoting stimuli, secrete the SASP (senescence-associated phenotypic) factors, and stably arrest the cell cycle. These proteins are rich in pro-inflammatory factors, such as interleukin (IL)-6, IL-8, C-X-C motif chemokine ligand 1, C–C motif chemokine ligand (CCL)2, CCL5, and matrix metalloproteinase 3. This study aimed to investigate the desmoplasia-like changes in the TME before and after cancer drug therapy in oral squamous cell carcinomas, evaluate the effect of anticancer drugs on the TME, and the potential involvement of cancer cell senescence. Using a syngeneic oral cancer transplant mouse model, we confirmed that cis-diamminedichloroplatinum (II) (CDDP) administration caused desmoplasia-like changes in cancer tissues. Furthermore, CDDP treatment-induced senescence in tumor-bearing mouse tumor tissues and cultured cancer cells. These results suggest CDDP administration-induced desmoplasia-like structural changes in the TME are related to cellular senescence. Our findings suggest that the administration of anticancer drugs alters the TME of oral cancer cells. Additionally, oral cancer cells undergo senescence, which may influence the TME through the production of SASP factors