Strong Coulomb interaction in 2D materials provides unprecedented
opportunities for studying many key issues of condensed matter physics, such as
co-existence and mutual conversions of excitonic ...complexes, fundamental optical
processes associated with their conversions, and their roles in the celebrated
Mott transition. Recent lasing demonstrations in 2D materials raise important
questions about the existence and origin of optical gain and possible roles of
excitonic complexes. While lasing occurred at extremely low densities dominated
by various excitonic complexes, optical gain was observed in the only
experiment at densities several orders of magnitude higher, exceeding the Mott
density. Here, we report a new gain mechanism involving charged excitons or
trions well below the Mott density in 2D molybdenum ditelluride. Our combined
experimental and modeling study not only reveals the complex interplays of
excitonic complexes well below the Mott transition, but also provides
foundation for lasing at extremely low excitation levels, important for future
energy efficient photonic devices.
Musashi1 (Msi1), a member of the RNA-binding protein (RBP) family, is highly expressed in neural progenitor or stem cells for the maintenance of stemness as well as in various cancers. Emerging ...studies have demonstrated that it regulates cell processes by translational activation or suppresses specifically bound mRNA. In the present study, we initially reported remarkably increased expression of Msi1 in colon cancer tissues compared with adjacent non-tumor tissues. Knockdown of Msi1 significantly suppressed the proliferation, colony formation, tumorsphere formation and the progression of implanted colon cancers, and induced cell cycle attest at G0/G1 phase, along with the upregulated expression of p21(cip1). Reporter assays using a chimeric mRNA that combined luciferase and the 3'-UTR of p21(cip1) revealed that Msi1 decreased the reporter activity through the specific motif. Thus, the current results suggested that downregulation of Msi1 could inhibit the growth of colon cancers and Msi1 may be a promising therapeutic target molecule for human colon cancers.
In order to protect the sensitive information in collaborative manufacturing grid environment, an access control solution was proposed to satisfy the inherent dynamic natures of the Manufacturing ...Grid, including dynamic Business Flow and system environment. In this solution, the Manufacturing Context-Aware Grid Access Control (MG_TC-RBAC) model extended the Role based Access Control (RBAC) model, activity is used to encapsulate user's role and relevant permission, and the user's permission is accurate by task and environment context. This model can be used as a reference basis for the Manufacturing Grid security problem.
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