The quasi-particle gap in a disordered boson Hubbard model in two dimensions

We investigate the behavior of the quasi-particle energy gap near quantum phase transitions in a two-dimensional disordered boson Hubbard model at a commensurate filling. Via Monte Carlo simulations of ensembles with fixed numbers of particles, we observe the behavior of the gap as a function of the tuning parameter for various strength of diagonal disorder. For weak disorder, we find that gapped Mott insulating phase is sustained up to the transition point and disappears only in a superfluid, strongly supporting a direct Mott-insulator-to-superfluid transition. Bose glass behavior, insulating with vanishing gap, appears only when the strength of disorder is bigger than a critical value

A novel design of 3D-bioprocess for embryonic stem cell expansion and differentiation: in vitro skeletal lineage tissue generation

Embryonic stem cells (ESCs) are known for their ability to be maintained almost indefinitely in an undifferentiated, proliferating state with the potential to give rise to all the cell types. Current strategies for the differentiation of ESCs are limited by their inability to control differentiation resulting in a heterogeneous cell population. Addressing this limitation, it has been previously reported that treatment with HepG2-conditioned medium (HepG2-CM) enhances the formation of multipotent mesodermal progenitors from ESCs. This promotes greater control of ESC differentiation in a lineage-specific fashion possibly resulting in efficient skeletal differentiation, which is an observation demonstrated by our group. In this study, by regulating culture time, preferential differentiation to either the osteogenic or cardiomyogenic lineage from murine ESCs was achieved using HepG2-CM in a three-dimensional integrated bioprocess. In addition, an automatable and scalable bioprocess was developed through the design, fabrication, and testing of a novel perfusion bioreactor system that has improved mineralised cellular construct generation. Finally, an animal pilot study was conducted to evaluate the efficacy and toxicity of our mineralised cellular construct

Colonial transition to modern economic growth in Korea and Taiwan

Rapid improvement in the living standards of Taiwan and South Korea during the recent decades is a familiar story. The economic development of the two countries in the first half of the 20th century is less known, however. Taiwan became a colony of Japan in 1895, and Korea in 1910. Using national income statistics, we argue that the Japanese colonial rule not only initiated the transition to modern economic growth, but also had lasting influence upon the post-colonial growth in Taiwan and South Korea. In order to understand the economic transformation of the two economies, we study the development policies of the Japanese colonial government. In discussing Korean development, we have taken advantage of the data availability to do growth accounting analysis. We identify key factors driving Korea out of secular stagnation and initiating the sustained growth. In the case of Taiwan, we compare the self-strengthening reform movement of late Ch’ing and the Japanese development policies, and try to identify the most important factors to development. In the following, we discuss the development of the two countires sequentially