Tokyo Institute of Technology

About: Tokyo Institute of Technology is a education organization based out in Tokyo, Tôkyô, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 46775 authors who have published 101656 publications receiving 2357893 citations. The organization is also known as: Tokyo Tech & Tokodai.

Peptide imprinted polymer nanoparticles: a plastic antibody

Abstract: A novel method for preparation of biomacromolecular imprinted nanoparticles is described. Combinations of functional monomers were polymerized in the presence of the imprinting peptide melittin in aqueous solution at room temperature to produce a small library of polymer nanoparticles. The template peptide and unreacted monomers are subsequently removed by dialysis. Nanoparticles (NPs) from the library were evaluated for their binding to melittin by 27 MHz QCM analysis. NPs prepared with optimized functional monomer combinations bind strongly to the target molecule. Nanoparticles that were polymerized in the absence of template peptide were found to have little affinity to the peptide. Binding affinity and the size of imprinted particles are comparable to those of natural antibodies. They interact specifically with the target peptide and show little affinity for other proteins. These NPs are of interest as inert and stable substitutes for antibodies. Extension of this approach to other targets of biological importance and the applications of these materials are currently being evaluated.

Edge state on hydrogen-terminated graphite edges investigated by scanning tunneling microscopy

Abstract: The edge states that emerge at hydrogen-terminated zigzag edges embedded in dominant armchair edges of graphite are carefully investigated by ultrahigh-vacuum scanning tunneling microscopy (STM) measurements. The edge states at the zigzag edges have different spatial distributions dependent on the $\ensuremath{\alpha}$- or $\ensuremath{\beta}$-site edge carbon atoms. In the case that the defects consist of a short zigzag (or a short Klein) edge, the edge state is present also near the defects. The amplitude of the edge state distributing around the defects in an armchair edge often has a prominent hump in a direction determined by detailed local atomic structure of the edge. The tight binding calculation based on the atomic arrangements observed by STM reproduces the observed spatial distributions of the local density of states.

Dynamic walking control of a biped robot along a potential energy conserving orbit

Abstract: To reduce the complex walking dynamics of a biped, a particular class of trajectories of an ideal biped model where the center of gravity of the body moves horizontally and the horizontal motion of the center of gravity can be expressed by a simple linear differential equation is introduced. The authors coin the phrase 'potential energy conserving orbit' to describe this class of trajectories. Based on these properties, control laws were formulated for walk initiation, walk continuation, and walk termination. The walking motion is controlled by support leg exchange. Robust realization of the walking control is also considered. An experimental walking machine was designed as a nearly ideal biped model. To make the legs lighter, four DC motors were mounted in the body, and the legs are parallel link structures. The results of the experiment describe five steps of dynamic walking including walk initiation. >

Evidence that p-tefb alleviates the negative effect of dsif on rna polymerase ii-dependent transcription in vitro

Abstract: Recently, a positive and a negative elongation factor, implicated in 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) inhibition of transcription elongation, has been identified. P-TEFb is a positive transcription elongation factor and the DRB-sensitive kinase that phosphorylates the C-terminal domain (CTD) of the largest subunit of RNA polymerase II (Pol II). PITALRE, a member of the Cdc2 family of protein kinases, is the catalytic subunit of P-TEFb. DSIF is a human homolog of the yeast Spt4-Spt5 complex and renders elongation of transcription sensitive to DRB. DRB sensitivity-inducing factor (DSIF) binds to RNA Pol II and may directly regulate elongation. Here we show a functional interaction between P-TEFb and DSIF. The reduction of P-TEFb activity induced by either DRB, antibody against PITALRE, or immunodepletion resulted in a negative effect of DSIF on transcription. DSIF acts at an early phase of elongation, and the prior action of P-TEFb makes transcription resistant to DSIF. The state of phosphorylation of CTD determines the DSIF-RNA Pol II interaction, and may provide a direct link between P-TEFb and DSIF. Taken together, this study reveals a molecular basis for DRB action and suggests that P-TEFb stimulates elongation by alleviating the negative action of DSIF.