Cyclic peptides hold great potential as therapeutic agents and research tools, but their broad application has been limited by poor membrane permeability. Here, we report a potentially general approach for intracellular delivery of cyclic peptides. Short peptide motifs rich in arginine and hydrophobic residues (e.g., FΦRRRR, where Φ is L-2-naphthylalanine), when embedded into small- to medium-sized cyclic peptides (7–13 amino acids), bound to the plasma membrane of mammalian cultured cells and were subsequently internalized by the cells. Confocal microscopy and a newly developed peptide internalization assay demonstrated that cyclic peptides containing these transporter motifs were translocated into the cytoplasm and nucleus at efficiencies 2–5-fold higher than that of nonaarginine (R9). Furthermore, incorporation of the FΦRRRR motif into a cyclic peptide containing a phosphocoumaryl aminopropionic acid (pCAP) residue generated a cell permeable, fluorogenic probe for detecting intracellular protein tyrosine phosphatase activities.

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Effect of heat-treatment on the activity of nickel phthalocyanine (NiPc) catalysts for oxygen reduction reaction (ORR) was studied in both acid and alkaline electrolytes. The catalytic activity was found to depend strongly on the electrolyte and heat treatment temperature. High ORR activity was demonstrated on 40%NiPc/C electrode in 0.1M KOH solution, and the heat-treatment of 800oC is optimal for the catalyst synthesized. Further using rotating disk electrode (RDE) measurements and Koutechy-Levich analysis, the overall electron transfer number in the catalyzed ORR on 40%NiPc/C was found to be 2.8, suggesting the catalyzed ORR proceeds via both the 2e- transfer reduction and the 4e- transfer reduction.

Due to the sustainable development of river system has been threatened, as the ecological function was decayed; more attention has been paid to the improvement of ecological environment, one prominent example is the river regulation and its environment construction. Besides flood protection, river can also create the plentiful habitat and unique regional culture by optimizing river regulation pattern. Therefore, the research on how to restore damaged river ecosystems to healthy status has become one of the important environmental issues urgent to be solved. Functional regionalization is the prerequisite for appropriate restoration, which can provide scientific basis for the goal of ecological restoration. In this paper, the Songhua River in Harbin is selected as a study case. Based on the theories of ecological function regionalization and the current situation of the Songhua River area, four-dimensional structure planning on the spatio-temporal scale of river corridor is developed in this paper, including longitudinal, lateral, vertical and temporal dimension. Considering the Songhua River area has typicality of characters in different time, with distinct four seasons, and the winter is very long, a detailed study and deeply analysis is discussed, then, measures for restoration and management are put forward.