Traversable Region Estimation for Mobile Robots in an Outdoor Image

This paper describes a novel method to estimate appropriate traversable regions from an outdoor scene image. The traversable regions output by the proposed method reflect the common sense of people. For example, a candidate traversable region is “a paved road somewhat distant from the side ditch.” The input to the traversable region estimation is one color image. First, category is assigned to each pixel in the image. The categorization result is then input to the region estimator. Finally, the traversable region are estimated on the input image. An important aspect of this method is the application of two score functions in region estimation process. One score function places high value on categories selected as traversable paths by subjects. The other function places high value on categories that are not selected as traversable regions but are adjacent to categories with traversable paths. A combination of these two functions produces feasible estimation results. The effectiveness of the combined score functions was evaluated by experiments and a questionnaire.     

Graft copolymerization to cellulose. Effect of sodium thiosulfate on hydrogen peroxide initiator system

The effect of sodium thiosulfate on the graft copolymerization of methyl methacrylate to cellulose in the hydrogen peroxide initiator system was investigated. The addition of sodium thiosulfate in general was effective for decreasing the per cent grafting and the average molecular weight of grafts and increasing the formation of homopolymer, and the effects became pronounced with increasing hydrogen peroxide concentration. Moreover, the addition of sodium thiosulfate slightly suppressed the formation of grafts at a hydrogen peroxide concentration of 3 mmole/l., but greatly promoted it at 20 mmole/l. Traces of metallic ions present in cellulose could not be eliminated sufficiently by treatment with 3N hydrochloric acid. Such ions were found to interact with hydrogen peroxide and thus participate directly in the initiation and termination of the polymerization reaction. EDTA, the chelating agent, was highly effective for suppressing such participation of metallic ions. In the hydrogen peroxide initiator system applied to the EDTA-treated samples, sodium thiosulfate caused an effective initiation of graft formation.     

Cellulose peroxides derived from carbonylated cellulose and hydrogen peroxide

Cellulose peroxides derived from hydrogen peroxide and cellulose derivative into which a ketone group is introduced by reaction with methyl vinyl ketone were investigated. The amount of peroxide formed on the cellulose substrate increased linearly with increasing carbonyl content of the sample, and sulfuric acid activated the formation of peroxide. The cellulose peroxide was gradually decomposed at 60°C in aqueous medium, and the decomposition was accelerated by addition of ferrous salt or irradiation with light of λ > 300nm. Grafting was initiated by adding methyl methacrylate to the thermal decomposition system under nitrogen. The formation, stability, thermal decomposition, and structure of the cellulose peroxide were discussed in comparison with one derived from aldehyde cellulose and hydrogen peroxide.     

Cathodic pulse breakdown of anodic films on aluminium in alkaline silicate electrolyte – Understanding the role of cathodic half-cycle in AC plasma electrolytic oxidation

Sequential anodic and cathodic pulse voltages were applied on anodised Al micro-electrodes in alkaline silicate electrolyte to explore the role of cathodic pulse in AC or bipolar plasma electrolytic oxidation (PEO) process. SEM observation was carried out to observe the sites of anodic and cathodic breakdown and their morphologies. The prior anodic breakdown accelerated the cathodic breakdown at ?50 V, and the acceleration was associated with the preferential cathodic breakdown at the anodic breakdown sites. However, the succeeding anodic breakdown during applying anodic pulse of 420 V for 2 ms was highly suppressed at the cathodic breakdown sites. This would randomise the anodic breakdown sites. Such role may contribute to the formation of rather uniform coatings on aluminium in this electrolyte without large discharge channels when larger cathodic current is applied with respect to the anodic current in AC PEO.     

In situ X-ray diffraction of surface oxide on type 430 stainless steel in breakaway condition using synchrotron radiation

Changes in the crystal structure of type 430 stainless steel and the oxides on its surface were studied in situ at 1373 K using a high-intensity synchrotron X-ray source provided by SPring-8 in Japan. The surface of the steel was initially covered with Cr₂O₃, which was then converted to FeCr₂O₄, and finally Fe₃O₄ and Fe₂O₃ formed on it. These results indicated that the reason for the breakaway oxidation in type 430 stainless steel is Cr depletion beneath Cr₂O₃ layer and the subsequent ionisation of Fe, not the simple mechanical failure of Cr₂O₃.     

Binding and Enhanced Binding between Key Immunity Proteins TRAF6 and TIFA

Human tumor necrosis factor receptor associated factor (TRAF)-interacting protein, with a forkhead-associated domain (TIFA), is a key regulator of NF-κB activation. It also plays a key role in the activation of innate immunity in response to bacterial infection, through heptose 1,7-bisphosphate (HBP); a metabolite of lipopolysaccharide (LPS). However, the mechanism of TIFA function is largely unexplored, except for the suggestion of interaction with TRAF6. Herein, we provide evidence for direct binding, albeit weak, between TIFA and the TRAF domain of TRAF6, and it is shown that the binding is enhanced for a rationally designed double mutant, TIFA S174Q/M179D. Enhanced binding was also demonstrated for endogenous full-length TRAF6. Furthermore, the structures of the TRAF domain complexes with the consensus TRAF-binding peptides from the C terminus of wild-type and S174Q/M179D mutant TIFA, showing salt-bridge formation between residues 177–181 of TIFA and the binding pocket residues of the TRAF domain, were solved. Taken together, the results provide direct evidence and a structural basis for the TIFA–TRAF6 interaction, and show how this important biological function can be modulated.     

Transmission electron microscopic study on supramolecular nanostructures of bacteriochlorophyll self-aggregates in chlorosomes of green photosynthetic bacteria

Supramolecular nanostructures of bacteriochlorophyll (BChl) self-aggregates in major light-harvesting complexes (chlorosomes) of green photosynthetic bacteria were successfully observed by freeze-fracture transmission electron microscope. Rod-shaped nanostructures with approximately 10 nm in diameter could be visualized in three types of green sulfur bacteria (Chlorobium). Diameter of the rod-shaped nanostructures in Chlorobium chlorosomes was independent of the molecular structures of their light-harvesting pigments, namely BChl-c or d. In contrast, chlorosomes of the green filamentous bacterium Chloroflexus aurantiacus had rod-shaped nanostructures with approximately 5 nm in diameter. The present results support that BChl self-aggregates in chlorosomes form rod-shaped nanostructures called rod-elements with approximately 10- and 5-nm diameters for Chlorobium and Chloroflexus, respectively.     

Analytical technique for thermoelectroelastic field in piezoelectric bodies with D∞ symmetry in cylindrical coordinates

A general solution technique for non-axisymmetric thermoelectroelastic problems in cylindrical domains with D_∞ symmetry is constructed. The displacement and electric field are expressed in terms of the respective potential functions, and the thermoelectroelastic field quantities are expressed in terms of the elastic and piezoelastic potential functions, each of which essentially satisfies a Laplace equation with respect to the spatial coordinates, combined with the two thermoelastic displacement potential functions. As an application of the technique, the theoretical analysis of a solid cylinder subjected to combined mechanical and thermal loading is performed, and the necessity of the thermoelectroelastic analyses is demonstrated.     

Cold-start performance of an ammonia-fueled spark ignition engine with an on-board fuel reformer

This work demonstrated the first-ever cold-start operation of an ammonia (NH₃)-fueled four-cylinder spark ignition engine with an on-board fuel reformer, applying autothermal reforming. In this system, an electrically heated NH₃-air mixture was provided to a reforming catalyst and approximately 3 s was found to elapse between the start of engine rotation and the onset of combustion. Stable fast idle operation in conjunction with a cold start was realized with a H₂-to-NH₃ molar ratio of 2:1. Nearly zero NH₃ emissions were achieved during cold start and fast idle until the engine warmed up, by adsorbing unburned NH₃ passing through a three-way catalyst before the catalyst was sufficiently warmed up. The NH₃ adsorption capacity of this system could be regenerated during the engine warm-up when the engine was running under lean conditions.     

Systematic analysis of glycosphingolipids in the human gastrointestinal tract: Enrichment of sulfatides with hydroxylated longer-chain fatty acids in the gastric and duodenal mucosa

The composition of the glycosphingolipids of the human gastrointestinal tract was studied. The major neutral glycosphingolipids were ceramide monohexosides (e.g., GalCer, GlcCer), LacCer, Gb₃Cer, Gb₄Cer and more polar ones with more than four sugars, whereas neither Gg₃Cer nor Gg₄Cer were present. The acidic glycosphingolipids consisted of sulfatides and gangliosides such as G_M3, G_M1, G_D3 and G_D1a. Also a large amount of sulfatides was found in the gastric mucosa and duodenum. The concentrations of sulfatides in the fundic mucosa, antral mucosa and duodenum amounted to 416.0, 933.8 and 682.9 nmol/g of dry weight, respectively, exceeding those in the gastric mucosa and kidney of other mammals. The major molecular species of the sulfatides were identified as I³SO₃-GalCer with hydroxylated longer-chain fatty acids based on the analyses by gas-liquid chromatography and negative ion fast-atom bombardment mass spectrometry. In contrast, gangliosides in these regions showed a tendency to be lower than sulfatides, and the molar ratios of sulfatides to gangliosides were about 2.0, whereas those in other parts were less than 0.5. A high content of sulfatides in the gastric and duodenal mucosa, where mucosa is easily insulted by acid, pepsin and bile salts, may be closely related to their roles in mucosal protection. The nomenclature used for gangliosides and other glycosphingolipids follows the system of Svennerholm (Ref. 1) and the recommendation of the IUPAC-IUB Commission (Ref. 2), respectively.