33 research outputs found
Dimerization of xanthene dyes in sol-gel titania films
Dye-dispersing titania gel films were prepared by the sol-gel method using titanium alkoxide solutions containing xanthene dyes, i.e., fluorescein, eosin Y, rhodamine 110, and rhodamine 123. Dimerization of the xanthene dyes in the films, depending on their concentrations, and their photoinduced electron transfer processes to the titania gels were investigated using spectroscopic and photoelectric techniques. The dye having a higher dimerization constant in solution formed a higher amount of the dimer in the titania gel. There was only a slight difference between the photoelectric conversion efficiencies of the monomer and dimer. The titanium species were coordinated to the carboxylate of the dyes. The dimers as well as the monomers were encapsulated in the narrow spaces of the gel films and strongly interacted with the surrounding titania matrix in the dye-dispersing titania gel films. The dye having a more nucleophilic carboxylate oxygen could easily form the coordination complex with the titanium species. The dye-titania interaction played an important role in the electron injection from the dye to the titania conduction band.ArticleCATALYSIS SCIENCE & TECHNOLOGY. 3(10):2786-2792 (2013)journal articl
Survey on the Family of the Recursive-Rule Extraction Algorithm
In this paper, we first review the theoretical and historical backgrounds on rule extraction from neural network ensembles. Because the structures of previous neural network ensembles were quite complicated, research on an efficient rule extraction algorithm from neural network ensembles has been sparse, even though a practical need exists for rule extraction in Big Data datasets. We describe the Recursive-Rule extraction (Re-RX) algorithm, which is an important step toward handling large datasets. Then we survey the family of the Recursive-Rule extraction algorithm, i.e. the Multiple-MLP Ensemble Re-RX algorithm, and present concrete applications in financial and medical domains that require extremely high accuracy for classification rules. Finally, we mention two promising ideas to considerably enhance the accuracy of the Multiple-MLP Ensemble Re-RX algorithm. We also discuss developments in the near future that will make the Multiple-MLP Ensemble Re-RX algorithm much more accurate, concise, and comprehensible rule extraction from mixed datasets
Seismic exploration at Fuji volcano with active sources : The outline of the experiment and the arrival time data
Fuji volcano (altitude 3,776m) is the largest basaltic stratovolcano in Japan. In late August and early September 2003, seismic exploration was conducted around Fuji volcano by the detonation of 500 kg charges of dynamite to investigate the seismic structure of that area. Seismographs with an eigenfrequency of 2 Hz were used for observation, positioned along a WSW-ENE line passing through the summit of the mountain. A total of 469 seismic stations were installed at intervals of 250-500 m. The data were stored in memory on-site using data loggers. The sampling interval was 4 ms. Charges were detonated at 5 points, one at each end of the observation line and 3 along its length. The first arrival times and the later-phase arrival times at each station for each detonation were recorded as data. P-wave velocities in the surface layer were estimated from the travel time curves near the explosion points, with results of 2.5 km/s obtained for the vicinity of Fuji volcano and 4.0 km5/s elsewhere
Human CYP24 Catalyzing the Inactivation of Calcitriol Is Post-Transcriptionally Regulated by miR-125b
A new technology for increasing therapeutic protein levels in the brain over extended periods.
Effective delivery of protein therapeutics into the brain remains challenging because of difficulties associated with crossing the blood-brain barrier (BBB). To overcome this problem, many researchers have focused on antibodies binding the transferrin receptor (TfR), which is expressed in endothelial cells, including those of the BBB, and is involved in receptor-mediated transcytosis (RMT). RMT and anti-TfR antibodies provide a useful means of delivering therapeutics into the brain, but the anti-TfR antibody has a short half-life in blood because of its broad expression throughout the body. As a result, anti-TfR antibodies are only maintained at high concentrations in the brain for a short time. To overcome this problem, we developed a different approach which slows down the export of therapeutic antibodies from the brain by binding them to a brain-specific antigen. Here we report a new technology, named AccumuBrain, that achieves both high antibody concentration in the brain and a long half-life in blood by binding to myelin oligodendrocyte glycoprotein (MOG), which is specifically expressed in oligodendrocytes. We report that, using our technology, anti-MOG antibody levels in the brains of mice (Mus musculus) and rats (Rattus norvegicus) were increased several tens of times for a period of one month. The mechanism of this technology is different from that of RMT technologies like TfR and would constitute a breakthrough for central nervous system disease therapeutics
Crystal structure of a YeeE/YedE family protein engaged in thiosulfate uptake
We have demonstrated that a bacterial membrane protein, YeeE, mediates thiosulfate uptake. Thiosulfate is used for cysteine synthesis in bacteria as an inorganic sulfur source in the global biological sulfur cycle. The crystal structure of YeeE at 2.5-Å resolution reveals an unprecedented hourglass-like architecture with thiosulfate in the positively charged outer concave side. YeeE is composed of loops and 13 helices including 9 transmembrane α helices, most of which show an intramolecular pseudo 222 symmetry. Four characteristic loops are buried toward the center of YeeE and form its central region surrounded by the nine helices. Additional electron density maps and successive molecular dynamics simulations imply that thiosulfate can remain temporally at several positions in the proposed pathway. We propose a plausible mechanism of thiosulfate uptake via three important conserved cysteine residues of the loops along the pathway