Production of lepidimoide by an endophytic fungus from polysaccharide extracted from Abelmoschus sp.: identification of the product and the organism producing it

A highly potent allelopathic factor, lepidimoide, was initially extracted from mucilage of germinated cress seeds. Polysaccharide extracted from okra (Abelmoschus esculentum Moench) is considered to have a similar structure to lepidimoide as its repeating unit. We therefore initiated the screening of enzymes capable of degrading okra polysaccharide into lepidimoide from endophytes. We discovered an endophytic fungal strain AHU9748 isolated from Coleus galeatus, which produced an oligosaccharide having similar properties to lepidimoide on thin layer chromatography. The physico-chemical data from ESI-MS, NMR spectra and other analyses also showed the purified product to be identical to lepidimoide. The strain AHU9748 was identified as a fungus belonging to the coelomycetes, closely related to the genus Colletotrichum, based on morphological characteristics and sequence analysis of the 18S rDNA and ITS region.     

Hairpin-based state machine and conformational addressing: Design and experiment

In this paper, we propose a new architecture for a multi-state DNA machine whose conformation of repeated hairpin structures changes sequentially in response to input oligomers. As an application of the machine, we also propose molecular memory in which the machine is used as a memory unit. Addressing in the memory is realized through state transitions of the machine. We then describe a method for designing DNA sequences of the machine, which exhaustively checks conformational changes of the machine by dividing its secondary structure into hairpin units. The method is based on the minimum free energy of the structure, the structure transition paths, and the total frequency of optimal and suboptimal structures. DNA sequences designed by the method were tested in a chemical experiment in which a machine consisting of two hairpins was actually constructed. As a result, we verified that the multi-state DNA machine realized the expected changes in its secondary structure.     

Multi-structure information retrieval method based on transformation invariance

The needs of efficient and flexible information retrieval on multi-structural data stored in database and network are significantly growing. Especially, its flexibility plays one of the key roles to acquire relevant information desired by users in retrieval process. However, most of the existing approaches are dedicated to a single content and data structure respectively, e.g., relational database and natural text. In this work, we propose “Multi-Structure Information Retrieval” (MSIR) approach applicable to various types of contents and data structures by adapting a small part of the approach to data structures. The power of this approach comes from the use of the invariant feature information obtained from byte patterns in the files through some mathematical transformation. The experimental evaluation of the proposed approach for both artificial and real data indicates its high feasibility. Fuminori Adachi: He received his Master of engineering from Osaka University in ’03. He is enrolled in the doctoral course of Osaka University from ’03. His current research interest includes scientific discovery, data mining and machine learning techniques. Takashi Washio, Ph.D.: He received his Ph.D. from Tohoku University in ’88. In ’88, he became a visiting reseacher in Massachusetts Institute of Technology. In ’90, he joined Mitsubishi Research Institute Inc., and is working for Osaka University from ’96. His current research interest includes scientific discovery, data mining and machine learning techniques. Atsushi Fujimoto: He is enrolled in the master cource of Osaka University from ’03. His Current research interest includes correlation analysis, data mining and machine learning techniques. Hiroshi Motoda, Ph.D.: He received his Ph.D. from University of Tokyo in ’72. In ’67, he joined Hitachi Ltd. and has been working for Osaka University since ’96. His current research interest includes scientific discovery, data mining and machine learning. Hidemitsu Hanafusa: He received Master of Engineering from Keio University in ’83. In ’83, he joined The Kansai Electric Power Co. Ins. (KEPCO). He researched on Maintenance Support System at INSS from ’97 to ’02. Now, he is working in KEPCO.     

An integrated model for the design of end-of-aisle order picking system and the determination of unit load sizes of AGVs

In this paper, we deal with an assembly line production system in which an automated guided vehicle (AGV) delivers parts to each workstation of assembly lines from a miniload automated storage/retrieval system (AS/RS). Each assembly production line is characterized by a sequence of workstations linked together for the production of a given type of product. We consider simultaneously the design problem of miniload AS/RS and the problem of determining a unit load size of the AGV. First, a non-linear mathematical model is formulated under a proposed AGV dispatching policy. And then, we determine an appropriate sequence of lines of the vehicle visits. Finally, based on the characteristics of the objective function and feasible region of the decision variables, a heuristic solution procedure is developed to find a near optimal solution. To examine the validity of the model, an example problem is solved.     

Tan δ of ethylene-propylene rubber in cryogenic temperature region–effects of additives and sample thickness

The authors have been developing extruded polymer insulated superconducting power cables. Dielectric loss in electrical insulation cannot be ignored in superconducting cables since conductor loss in the cables is minimal. Studies so far show that ethylene-propylene rubber (EPR) is suitable as an electrical insulating material in the extruded polymer insulated superconducting cable design because it demonstrates excellent mechanical and relatively good electrical qualities at a cryogenic temperature. Widely used EPR includes some kinds of additives; however, their effect on tan δ of EPR at cryogenic temperature remains unknown. The effect of additives such as crosslinking agent and fillers on tan δ of EPR was examined at temperatures of between 4.2 K and 300 K. Thickness dependence of tan δ was also measured using EPR films of different thickness and an extruded EPR insulated cable sample. The results show that additives increase tan δ of relatively thin films of EPR even in the cryogenic temperature region; however, they do not have an intolerable dielectric loss in comparison with conductor loss and heat inflow of the superconducting cable. The remedy to tan δ increase due to the polymer contraction relative to shielding wires has been established.     

Responses of maxillary sensilla styloconica inBombyx mori to glucosides fromOsmunda japonica,a nonhost plant

We isolated glucosides from the royal fern,Osmunda japonica, which elicit a deterrent response in larvae ofBombyx mori. These compounds were absent in taro (Colocasia antiquorum) and castor-oil plant (Ricinus communis) leaves and did not evoke responses of sensory cells in the lateral and medial sensilla styloconica ofSpodoptera litura. This glucoside extract of the royal fern leaves stimulates receptors generally associated with deterrent. It is also possible that this compound may act as a behavioral deterrent, and from actual feeding tests, it is suggested that this compound may prevent feeding in some monophagous insects, such asBombyx mori. The deterrent glucoside possesses a noncyclic aglycon.     

Observations of high-field domains in GaxIn1 ? xSb Gunn diodes

The properties of high-field domains in GaxIn1-xSb Gunn diodes (0.4 < x < 0.82) have been studied by measuring the surface potential on the diodes. The domain velocities vary with the Ga composition x, 5.3?6.1×106 cm/s for0.8 > x > 0.55 and 10×106 cm/s for x = 0.4, but they are almost independent of the applied voltage, even if the electron concentration is increased by the impact ionisation in the domain at high applied voltages for the small-x samples.     

Production of vitamin B12 in genetically engineered Propionibacterium freudenreichii

Since the chemical synthesis of vitamin B12 requires more than 70 steps, the production of vitamin B12 has been achieved by microorganism fermentation with additional brief chemical modifications. In an effort to increase the productivity of vitamin B12, we tried to express 10 genes belonging to the hem, cob and cbi gene families involved in the synthesis of vitamin B12 in Propionibacterium freudenreichii, which is a known producer of vitamin B12. In a recombinant P. freudenreichii clone that harbored the expression vector containing a cobA, cbiLF, or cbiEGH, we obtained an increase in vitamin B12 production of 1.7-, 1.9-, and 1.5-fold higher, respectively, than that in the microorganism without any cloned genes in the expression vector pPK705. The cobU and cobS genes caused a slight increase in the production of vitamin B12. Furthermore, we achieved multigene expression in P. freudenreichii. In a recombinant P. freudenreichii clone that harbored an exogenous gene, hemA, from Rhodobacter sphaeroides and endogenous hemB and cobA genes, we successfully achieved the production of about 1.7 mg/l vitamin B12, 2.2-fold higher than that produced by P. freudenreichii harboring pPK705.     

Hiding an image with a light-scattering medium and use of a contrast-discrimination method for readout

Hiding image data with a material such as a light-scattering medium is useful as an initial stage of data protection, because the hidden image can be detected only by observation with a specific technique. A light-scattering medium is used to hide the image data, and a low-temporal-coherence interferometer performs the readout processing. A new readout method for detecting pixel values of the image is proposed to overcome spatial variation of the light intensity and distortion of the interference fringes. The introduction of spatial coding further improves the performance by overcoming spatial variations of the light-scattering medium and variations in the reflectance of given pixels.