High-Scale SUSY Breaking Models in light of the BICEP2 Result

The large value of the tensor-to-scalar ratio in the cosmic microwave background radiation reported by the BICEP2 collaboration gives strong impact on models of supersymmetry (SUSY). The large ratio indicates inflation with a high-energy scale and thus a high reheating temperature in general, and various SUSY models suffer from the serious gravitino and Polonyi problems. In this article, we discuss a class of the high-scale SUSY breaking models which are completely free from those problems. With especially focusing on the dark matter relic abundance, we examine how the BICEP2 result narrows down the parameter space of the models, assuming the simplest chaotic inflation model. We find that the mass of the dark matter is predicted to be less than about 1 TeV thanks to the non-thermal production in the early universe through the decay of abundant gravitinos produced after the reheating process. We also discuss implications in some details to dark matter searches at collider and indirect dark matter detection experiments.Comment: 17 pages, 6 figure

Areal distribution of water-insoluble particles in snow covers of the central mountainous area, Japan

The vertical snow samples collected from 6 locations (Iou-zen: 800m A.M.S.L; the nearest site from the Sea of Japan, Kongoudou-zan: 1300m, Nishi-Hodaka-Dake: 2200m; the Northern Japan Alps, Hachimori-yama: 2100m, Kiriga-mine: 2000m, Yatsuga-take: 2200m; the most inlying site) in the central mountainous area, Japan, during early spring season 2004, were analyzed for size-separated concentrations of water-insoluble particles in snow layers to investigation of long-range transportation of chemical substances from the Asian continent to high mountainous areas in Japan. Most of particles are less than 30 μm in diameter, the greater part of particles observed at the 6 locations were considered to be transported from the Asian continent sources as Asian dust (KOSA). The variation patterns of the vertical profiles of particle concentrations in snow layers were corresponding among each location. The concentrations of particles with less than 30 μm was gradually increased with increasing distance from the Sea of Japan to the Japan Alps, although, sharply-decreased at 3 sites located the monsoon-leeward of the Japan Alps, suggesting that the particles transported with monsoon were gradually removed from air and deposited in snow cover when the air parcel pass through the Japan Alps

Hepatocyte growth factor in physiology and infectious diseases

Hepatocyte growth factor (HGF) is a pleiotropic cytokine composed of an α-chain and a β-chain, and these chains contain four kringle domains and a serine protease-like structure, respectively. The receptor for HGF was identified as the c-met proto-oncogene product of transmembrane receptor tyrosine kinase. HGF-induced signaling through the receptor Met provokes dynamic biological responses that support morphogenesis, regeneration, and the survival of various cells and tissues, which includes hepatocytes, renal tubular cells, and neurons. Characterization of tissue-specific Met knockout mice has further indicated that the HGF-Met system modulates immune cell functions and also plays an inhibitory role in the progression of chronic inflammation and fibrosis. However, the biological actions that are driven by the HGF-Met pathway all play a role in the acquisition of the malignant characteristics in tumor cells, such as invasion, metastasis, and drug resistance in the tumor microenvironment. Even though oncogenic Met signaling remains the major research focus, the HGF-Met axis has also been implicated in infectious diseases. Many pathogens try to utilize host HGF-Met system to establish comfortable environment for infection. Their strategies are not only simply change the expression level of HGF or Met, but also actively hijack HGF-Met system and deregulating Met signaling using their pathogenic factors. Consequently, the monitoring of HGF and Met expression, along with real-time detection of Met activation, can be a beneficial biomarker of these infectious diseases. Preclinical studies designed to address the therapeutic significance of HGF have been performed on injury/disease models, including acute tissue injury, chronic fibrosis, and cardiovascular and neurodegenerative diseases. Likewise, manipulating the HGF-Met system with complete control will lead to a tailor made treatment for those infectious diseases. © 2016 Elsevier Ltd.Embargo Period 12 month