Bistability and Oscillations in Gene Regulation Mediated by Small Noncoding RNAs

The interplay of small noncoding RNAs (sRNAs), mRNAs, and proteins has been shown to play crucial roles in almost all cellular processes. As key post-transcriptional regulators of gene expression, the mechanisms and roles of sRNAs in various cellular processes still need to be fully understood. When participating in cellular processes, sRNAs mainly mediate mRNA degradation or translational repression. Here, we show how the dynamics of two minimal architectures is drastically affected by these two mechanisms. A comparison is also given to reveal the implication of the fundamental differences. This study may help us to analyze complex networks assembled by simple modules more easily. A better knowledge of the sRNA-mediated motifs is also of interest for bio-engineering and artificial control

Fluorographene: A Wide Bandgap Semiconductor with Ultraviolet Luminescence

The manipulation of the bandgap of graphene by various means has stirred great interest for potential applications. Here we show that treatment of graphene with xenon difluoride produces a partially fluorinated graphene (fluorographene) with covalent C-F bonding and local sp(3)-carbon hybridization. The material was characterized by Fourier transform Infrared spectroscopy, Raman spectroscopy, electron energy loss spectroscopy, photoluminescence spectroscopy, and near edge X-ray absorption spectroscopy. These results confirm the structural features of the fluorographane with a bandgap of 3.8 eV, close to that calculated for fluorinated single layer graphene, (CF)(n). The material luminesces broadly in the UV and visible light regions, and has optical properties resembling diamond, with both excitonic and direct optical absorption and emission features. These results suggest the use of fluorographane as a new, readily prepared material for electronic, optoelectronic applications, and energy harvesting applications.close14010