Preparation of concentrated multilayer graphene dispersions and TiO2-graphene composites for enhanced hydrogen production

Photocatalytic hydrogen (H2) production is an attractive hydrogen production technology. It is initiated by charge-separation in titanium (IV) dioxide (TiO2) upon photoexcitation. Electrons reduce water to generate H2 while holes oxidize hydroxide to generate hydroxyl radicals. TiO2 is widely used because it is inexpensive, chemically stable, nontoxic, and environmentally friendly. The activity of TiO2 is limited, but adding a supporting noble metal nanoparticle such as platinum greatly enhances it. Due to resource risks and cost issues, we consider using graphene as an alternative to noble metal nanoparticles. Herein we report a new method to prepare a concentrated multilayer graphene solution and hydrogen production from an aqueous methanol solution. When we used graphene with different sheet sizes or improved the aggregation of TiO2 (TIO-9), the H2 evolution rate is 1.6 times higher than that of pristine TIO-9. The contact state and the dispersed state of graphene and TiO2 play important roles in improving the activity

Biological Convergence of Cancer Signatures

Gene expression profiling has identified cancer prognostic and predictive signatures with superior performance to conventional histopathological or clinical parameters. Consequently, signatures are being incorporated into clinical practice and will soon influence everyday decisions in oncology. However, the slight overlap in the gene identity between signatures for the same cancer type or condition raises questions about their biological and clinical implications. To clarify these issues, better understanding of the molecular properties and possible interactions underlying apparently dissimilar signatures is needed. Here, we evaluated whether the signatures of 24 independent studies are related at the genome, transcriptome or proteome levels. Significant associations were consistently observed across these molecular layers, which suggest the existence of a common cancer cell phenotype. Convergence on cell proliferation and death supports the pivotal involvement of these processes in prognosis, metastasis and treatment response. In addition, functional and molecular associations were identified with the immune response in different cancer types and conditions that complement the contribution of cell proliferation and death. Examination of additional, independent, cancer datasets corroborated our observations. This study proposes a comprehensive strategy for interpreting cancer signatures that reveals common design principles and systems-level properties