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Abstract It is difficult to determine whether an individual therapy contributes to the elongation of survival because of the difficulty of organizing clinical research in patients who receive multiple treatments in HCC. We aimed to establish a new model of survival prediction in patients with intermediate stage HCC to establish standards in the recent and coming multi-MTA era. This analysis was prepared using a data set of 753 patients diagnosed HCC prior to 2017. Multiple regression analysis showed age, naïve or recurrence, the size of the largest tumor nodule, the number of nodules, total bilirubin, albumin and α-fetoprotein as independent predictors of survival. A Weibull model had the best fit and, based on these predictors, we established a new predicted survival model. The survival duration can be predicted the proposed model; EXP (4.02580 + (− 0.0086253) × age + (− 0.34667) × (naïve/recurrence) + (− 0.034962) × (number of nodules) + (− 0.079447) × (the size of the largest nodule) + (− 0.21696) × (total bilirubin) + 0.27912 × (albumin) + (− 0.00014741) × (α-fetoprotein)) × (− natural logarithm(0.5))^0.67250. This model is useful for the planning and evaluating the efficacy of recent sequential therapies in multi-MTA era.

We present here the East Asia to Italy Nearly Global VLBI (EATING VLBI) project. How this project started and the evolution of the international collaboration between Korean, Japanese, and Italian researchers to study compact sources with VLBI observations is reported. Problems related to the synchronization of the very different arrays and technical details of the telescopes involved are presented and discussed. The relatively high observation frequency (22 and 43 GHz) and the long baselines between Italy and East Asia produced high-resolution images. We present example images to demonstrate the typical performance of the EATING VLBI array. The results attracted international researchers and the collaboration is growing, now including Chinese and Russian stations. New in progress projects are discussed and future possibilities with a larger number of telescopes and a better frequency coverage are briefly discussed herein.

Simultaneous multi-band very long baseline interferometry (VLBI) observations at millimeter wavelengths have huge potential for various science cases. However, there exist difficulties in expanding the scientific targets, as the sensitivity of radio telescopes at millimeter wavelengths is typically lower compared to that at centimeter wavelengths. In order to realize high-sensitivity mm-VLBI observations in the East Asia region, we are promoting the HINOTORI (Hybrid Installation project in NObeyama, Triple-band ORIented) project, which aims to launch the wide-band and simultaneous triple-band (22/43/86 GHz) VLBI system with the Nobeyama 45 m Radio Telescope (NRO45). The simultaneous 22/43 GHz observation mode has already been operated for the open-use program. We have recently completed the performance evaluation of the receiver and observing system at 86 GHz. In addition, a new wide-band VLBI back-end system has been installed on the NRO45 and the performance of this receiving system has been found to be sufficient to meet scientific requirements. Currently, we are performing commissioning observations to establish regular VLBI operation with simultaneous triple-band mode together with the Korean VLBI Network. The participation of the NRO45 is expected to strengthen the mm-VLBI observation network in the East Asia region and to be a very powerful addition with respect to the science of of black hole jets.

The radio galaxy NGC 1052 casts absorption features of sulfur-bearing molecules, H _2 S, SO, SO _2 , and CS toward the radio continuum emission from the core and jets. Using the Atacama Large Millimeter/submillimeter Array, we have measured the equivalent widths of SO absorption features in multiple transitions and determined the temperatures of 344 ± 43 K and 26 ± 4 K in submillimeter and millimeter wavelengths, respectively. Since submillimeter and millimeter continuum represents the core and jets, the high and low temperatures of the absorbers imply a warm environment in the molecular torus and cooler downstream flows. The high temperature in the torus is consistent with the presence of 22 GHz H _2 O maser emission, vibrationally excited HCN and HCO ^+ absorption lines, and sulfur-bearing molecules in the gas phase released from dust. The origin of the sulfur-bearing gas is ascribed to the evaporation of the icy dust component through a jet–torus interaction. Shock heating is the sole plausible mechanism to maintain such a high temperature of gas and dust in the torus. The implication of the jet–torus interaction also supports the collimation of the sub-relativistic jets by the gas pressure of the torus.

The East Asian VLBI Network (EAVN) is an international VLBI facility in East Asia and is operated under mutual collaboration between East Asian countries, as well as part of Southeast Asian and European countries. EAVN currently consists of 16 radio telescopes and three correlators located in China, Japan, and Korea, and is operated mainly at three frequency bands, 6.7, 22, and 43 GHz with the longest baseline length of 5078 km, resulting in the highest angular resolution of 0.28 milliarcseconds at 43 GHz. One of distinct capabilities of EAVN is multi-frequency simultaneous data reception at nine telescopes, which enable us to employ the frequency phase transfer technique to obtain better sensitivity at higher observing frequencies. EAVN started its open-use program in the second half of 2018, providing a total observing time of more than 1100 h in a year. EAVN fills geographical gap in global VLBI array, resulting in enabling us to conduct contiguous high-resolution VLBI observations. EAVN has produced various scientific accomplishments especially in observations toward active galactic nuclei, evolved stars, and star-forming regions. These activities motivate us to initiate launch of the ’Global VLBI Alliance’ to provide an opportunity of VLBI observation with the longest baselines on the earth.