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Shinohara W.,Kyoto University | Ushio Y.,Incorporated Administrative Agency | Seo A.,Humanity | Nakato N.,Narahashi 1 363 | And 4 more authors.
Systematic Botany | Year: 2010

Several cytotypes (polyploids and aneuploids) have been reported in Lepisorus thunbergianus. The relationships between these cytotypes within the species remain poorly understood. We studied populations in an area where various cytotypes of L. thunbergianus as well as two diploid species, L. angustus and L. onoei, candidate parental species that may be involved in allopolyploid origins of L. thunbergianus polyploids, occur. We determined the ploidy levels of sampled materials by direct chromosome counting and flow cytometry. We elucidated the origins of L. thunbergianus polyploids by analyzing allozyme polymorphisms, and in addition, we examined the occurrence of segmental allopolyploidy by comparing allelic variation between polyploids and their parental diploids. Six cytotypes, i.e. one diploid (2n = 50), two triploid (2n = 75 and 76) and three tetraploid (2n = 100, 101, and 102) cytotypes, were observed in L. thunbergianus, and the two diploid species, L. angustus (2n =52) and L. onoei (2n =50) were confirmed to include a single cytotype each. Allozyme analyses indicated that the tetraploid (2n =100) and hypertetraploid (2n = 102) of L. thunbergianus originated by allopolyploidy between diploid L. thunbergianus (2n = 50) and diploid L. angustus (2n = 52), since the polyploids shared alleles with these two diploids that were unique to each diploid. The allozyme patterns excluded the possibility that L. thunbergianus polyploids originated from L. onoei. The unbalanced heterozygosity and homozygosity found in the tetraploid and the hypertetraploid of L. thunbergianus indicated their segmental allopolyploidy. © Copyright 2010 by the American Society of Plant Taxonomists. Source

Inoue K.,Incorporated Administrative Agency | Wakabayashi F.,National Museum of Nature and Science | Domen K.,University of Tokyo
Catalysis Letters | Year: 2012

Pre-adsorbed DCOO(a) on Cu(110) was exchanged with HCOO(a) in the presence of HCOOD gas at 300 K. The DCOO(a) desorbed as DCOOD after accepting a deuterium atom from the introduced HCOOD. The exchange reaction rate on Cu(110) was over 5 times faster than that on Ni(110) reported previously. This was a result of differences in the interactions between the metal surfaces and the formate. © Springer Science+Business Media New York 2012. Source

Kagawa H.,University of Miyazaki | Fujie N.,University of Miyazaki | Imaizumi H.,Japan National Research Institute of Fisheries And Environment of Inland Sea | Masuda Y.,Japan National Research Institute of Fisheries And Environment of Inland Sea | And 6 more authors.
Aquaculture | Year: 2013

This study examines how the continuous administration of various hormones using an osmotic pump, a long-term sustained hormone release system, influences the induction of sexual maturation in females of the Japanese eel, Anguilla japonica. Human chorionic gonadotropin (hCG), salmon pituitary extract (SPE), and gonadotropin-releasing hormone analogue (GnRHa) were tested, and the consequent egg quality was evaluated. The implantation of osmotic pumps loaded with SPE induced vitellogenesis and increased the gonadosomatic index (GSI) at 39-110 days. In comparison, pumps loaded with hCG inconsistently induced early vitellogenesis, while those loaded with GnRHa did not exhibit any stimulatory effect. Fewer eels attained full maturity when using the osmotic pump system compared with SPE-injected female eels. However, after the final treatment, the number of eels that ovulated and the time required for ovulation were similar for both the osmotic pump and injection groups. Moreover, more eggs were spawned in the SPE-loaded osmotic pump group than in the SPE-injected group. Egg quality was similar for both experimental groups. Therefore, the implantation of an osmotic pump loaded with SPE represents a reliable method for inducing vitellogenesis and obtaining ovulated eggs from sexually immature Japanese eels. © 2013 Elsevier B.V. Source

Fujino K.,Incorporated Administrative Agency | Nagatani K.,Tohoku University | Yuta S.,Shibaura Institute of Technology
ISARC 2013 - 30th International Symposium on Automation and Robotics in Construction and Mining, Held in Conjunction with the 23rd World Mining Congress | Year: 2013

Severe disasters have struck Japan in recent years. Following these disasters, construction robots have played important roles in investigation and restoration work in the disaster regions. To be applied in this way, construction robots require many functions according to the purpose of their use in each case. There are clear differences in the functions and usage conditions required by investigation robots and those required by execution robots. These differences will be important when designing and operating construction robots in the future. This report introduces a volcano exploration robot and unmanned execution system as examples of construction robots used for investigations and executions respectively. Based on this, the report organizes important characteristics of construction robots and explains differences in the concepts of disaster investigation robots and disaster restoration robots. Because they are used in harsh natural conditions and do not have any execution functions, efforts are made to clarify the fact that investigation robots have to overcome many problems such as mobility. When a construction robot is used, the scenario of the operation of the construction robot (execution plan) is extremely important, and in addition, it is necessary to clearly define the way it will be used according to the purpose of its use and specification conditions. In a plan for an unmanned execution system, it is possible to mitigate several strict prerequisite conditions by proposing a well-constructed execution plan. For example, the execution efficiency of an unmanned execution system can be improved by effectively using a temporary road. Source

A water-soluble iron-supplying agent including a reaction product as an active ingredient, in which the reaction product is obtained by using roasted and ground coffee beans and/or tea leaves as feedstocks for supplying a metal ion-solubilizing component, and mixing the feedstocks for supplying the metal ion-solubilizing component with an iron-supplying source containing trivalent iron in the presence of water; specifically, a water-soluble iron-supplying agent which can reduce trivalent iron into a divalent iron ion and maintain the divalent iron ion to supply a water-soluble iron ion (divalent iron ion) stably for a long period of time.

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