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Callicarpa subpubescens is endemic to the oceanic Ogasawara Islands, and multiple ecotypes have been suggested to exist within southern part of this group, the Hahajima Islands, each associated with unique localized habitats. We determined the habitat characteristics of each ecotype, the presence or absence of pre- and post-mating isolation, the amount of gene flow among ecotypes in adult trees and naturally pollinated seeds using EST-SSR markers, and discussed how ecotypes are maintained in this species. There were four ecotypes in the Hahajima Islands, one of which presumed to be derived from hybridization of the remaining two ecotypes. The spatial distribution and habitat of each ecotype showed distribution which have depended on the suitable environment for each ecotype, i.e. local adaptation. The leaf morphology and size distribution of each ecotype also indicated the appropriate forms for each habitat. Flowering times more or less overlap among the ecotypes, indicating that pre-mating isolation is not perfect. Artificial cross-pollination showed that no post-mating isolation exists between ecotypes. Hybridization rates in adult trees and naturally pollinated seeds were 37.2% and 26.4%, respectively, and most of the hybrids were backcrosses and few F1. The hybridization rates of each ecotype and paternal correlation indicated that the flowering synchrony and spatial distribution of ecotypes contributed to hybridization among ecotypes. The reversion to the original ecotype which adapted to the environment through backcrossing would contribute to the maintenance of the ecotypes.

A new electron accelerator has been designed and is now under construction at AIST, Tsukuba, Japan. The accelerator will be used to produce a pulsed neutron beam for materials analysis. The design maximizes the yield of slow neutrons with high pulse temporal resolution as described in a previous publication [K. Kino et al., Nuclear Inst. and Methods in Physics Research, A 927 (2019) 407–418]. The accelerator is composed of a thermal cathode type electron gun with S-Band buncher/accelerator cavity followed by three, 2.9 m long S-Band acceleration cavities. High power RF is supplied by three klystron units, with klystron No.1 supplying both the electron gun and the 1st cavity, and klystrons No.2 and No.3 connected to the 2nd and 3rd cavities respectively. The design parameters of the accelerator are; pulse rate: 100 Hz, pulse length: 10 μs, electron current: 250 mA, electron energy: 40 MeV. Operating at these parameters a maximum beam power of around 10 kW will be delivered to the water-cooled Ta target for neutron production. In this report we will describe the design and construction of the electron accelerator.

Adaptive radiation is the diversification of a founding population into multiple taxa that are differentially adapted to diverse ecological niches. The three Callicarpa (Lamiaceae) species endemic to the Bonin Islands are considered to represent an example of adaptive radiation on oceanic islands. All three species are distributed in the Chichijima Island Group and grow in different habitats, while only one species, C. subpubescens, is distributed among other island groups. Particularly, in the Hahajima and Mukojima Island Groups, C. subpubescens grows in various habitats and shows relatively high morphological variation. We investigated genotypes of the three Callicarpa species at 14 microsatellite markers to elucidate genetic differentiation within and between species or island groups and between different habitats or morphologies. We found that genetic differentiation within C. subpubescens in the Hahajima and Mukojima Island Groups was equally as high as that between the three species in the Chichijima Island Group, while differentiation within C. subpubescens in the Chichijima Island Group was much lower. Analyses such as a Bayesian clustering analysis showed that genetically distinct groups were associated with the three species in the Chichijima Island Group, whereas they showed strong genetic structure within C. subpubescens in the Hahajima and Mukojima Island Groups among different habitats and morphologies. These results indicated that ecological diversification occurred in the Hahajima and Mukojima Island Groups. Meanwhile, high genetic differentiation among different island groups was also observed, reflecting isolation by distance. It implies that non-ecological factors such as geographic isolation also played important roles in genetic differentiation in Callicarpa species in the Bonin Islands. These findings suggest that the Callicarpa species in the Bonin Islands are differentiated into multiple genetic groups by both ecological and non-ecological factors.

The genus, Ochrosia, is widely distributed from the West Indian Ocean throughout tropical Asia to the Middle Southern Pacific region. Ochrosia comprises many island-endemic species, suggesting that long-distance dispersal and isolation after migration are key factors for clarifying the diversification process. However, the phylogeny and biogeography of endemic Ochrosia species have not been evaluated well due to the difficulty of adequate sampling from the entire distribution range of the genus. In this study, we focused on two Ochrosia species endemic to the Bonin (Ogasawara) Islands in the northwest Pacific. The Bonin Islands are of volcanic origins and consist of two islands groups, the Ogasawara and Volcano Islands groups, approximately 300 km apart. Ochrosia nakaiana is endemic to the Ogasawara Islands group, whereas O. hexandra is endemic to the Volcano Islands group. To elucidate the phylogenetic positions of these two endemic Ochrosia species, we conducted molecular phylogenetic studies with dating and biogeographic analyses including other Ochrosia species. The phylogenetic trees showed that the two endemic species had distinct origins; O. nakaiana was closely related to O. oppositifolia and O. iwasakiana, whereas O. hexandra was related to O. mariannensis. Based on the chloroplast DNA phylogeny, the genus, Ochrosia, divided into two major lineages 36.6 million years ago. Further, the two endemic species of the Bonin Islands were independently derived approximately 1-2 million years ago. Ochrosia nakaiana originated from the Southeast Asia, New Caledonia, or other Pacific Islands, while O. hexandra derived from O. mariannensis in Micronesia. We demonstrated different origins of the two endemic Ochrosia species on the Bonin Islands. This study provided an excellent example of the complex origins and speciation of flora in the oceanic islands.

OBJECTIVE To propose a simple grading of inner ear malformation (IEM) and investigate intracochlear electrical auditory brainstem response (EABR) and outcomes for hearing in terms of the novel grading system. STUDY DESIGN Retrospective case review. SETTING Tertiary referral center. PATIENTS Sixty patients with IEMs who received cochlear implants. INTERVENTION Grading according to observation of modiolus deficiency and/or internal auditory canal (IAC) cochlear nerve deficiency (CND). MAIN OUTCOME MEASURE Intracochlear EABR and categories of auditory performance (CAP) scores were assessed; children in school were categorized according to the type of school attended. RESULTS Among 60 patients, 38% were classified as Grade I (modiolus present + normal cochlear nerve), 22% as grade II (modiolus deficiency + normal cochlear nerve), 33% as grade III (modiolus present + IAC CND), and 7% as grade IV (modiolus deficiency + IAC CND). During the operation, 93% of Grade I, 36% of Grade II, 23% of Grade III, and 50% of Grade IV patients showed typical EABR waves. CAP scores of 4 or more were obtained from 91% of Grade I, 62% of Grade II, 35% of Grade III, and 25% of Grade IV. Whereas none of children in Grades III and IV entered main stream school, 55% of Grade I and 25% of Grade II entered mainstream schools. CONCLUSIONS Outcomes of hearing with cochlear implantations in IEM children depend on the severity of IEM and IAC CND. Our novel grading of IEM is simple and can be useful for understanding the severity of IEM.

We have constructed a compact accelerator-based neutron facility at the National Institute of Advanced Industrial Science and Technology (AIST) in Japan aiming at development of structural materials of transportation vehicles for weight reduction. The facility consists of electron linear accelerator, neutron source, and a neutron beamline with a measurement hutch. Currently we are commissioning the accelerator and expecting a first neutron beam in 2019.

Expressed sequence tagged (EST) microsatellite (SSR) markers were newly developed for Callicarpa subpubescens, a species endemic to the Bonin (Ogasawara) Islands of Japan, to investigate gene flow,...

Distyly is usually rare or not observed in species thriving on oceanic islands. The rarity of this breeding system is probably because of the difficulty of colonization for distylous plants and the paucity of pollinators on oceanic islands. However, the endemic and endangered tree Psychotria homalosperma has maintained its distylous nature in the oceanic Bonin Islands, Japan. To understand how the distylous breeding system of P. homalosperma has been maintained on these islands and to characterize the reproduction systems, we studied the pollination and reproductive biology of this species. Specifically, we observed current flower visitors and estimated their effects on plant reproduction. We also examined the floral traits and floral volatiles of P. homalosperma to infer its original pollinators, because plant–pollinator relationships in the Bonin Islands have recently been disrupted by anthropological activities. Finally, we examined the fruit set and pollen tube growth in the stigmas under hand and open pollination. Although original pollinators were presumed to be moths with long proboscises, the introduced honeybee, Apis mellifera, was the most common flower visitor. The honeybee carried pollen grains only unidirectionally, from the short- to long-styled morphs, because it could not reach the hidden stigmas of the short-styled flowers, and long-styled flowers set fruits 1.7–38 times more than short-styled ones. This case study indicates that the instability of pollinator fauna can cause distylous species to be rare on oceanic islands.

Microsatellite loci were developed for Gynochthodes boninensis, an endemic climbing plant in the Bonin Islands. Using a Roche 454 GS Junior next-generation sequencer, 158 microsatellite loci were designed. Of the 48 microsatellite loci tested, 37 were successfully amplified and 25 were polymorphic in two populations of G. boninensis. For the 25 polymorphic loci, the mean expected heterozygosities per locus were 0.303 in the Chichijima Island population and 0.310 in the Hahajima Island population, respectively. There was no evidence of linkage disequilibrium in either population, but one locus showed significant deviation from Hardy–Weinberg equilibrium in one population. The microsatellite loci developed in this study will be useful for future studies of population genetics of G. boninensis. In particular, because this species is androdioecious (males and hermaphrodites coexist), characterizing the species gene flow is crucial to understanding the evolution and maintenance of this rare sexual system.

Pandanus boninensis, endemic to the Ogasawara Islands, Japan, is distributed on both the older Bonin and younger Volcano Islands. In this study, we conducted population genetic analyses of P. boninensis on these islands to examine the population diversity and structure across old and young islands, to assess potential differences in population demography with island age, and to collect any evidence of migration between old and young islands. We found that the genetic diversity of expressed sequence tag (EST)-based microsatellite (SSR) markers, the nucleotide diversity of nuclear DNA sequences, and the haplotype diversity of chloroplast DNA on young islands were lower than those on old islands. Clustering analyses of EST-SSR indicated that populations on old islands were strongly diverged from those on young islands. Approximate Bayesian computation analysis of EST-SSR suggested that population expansion occurred on old islands while population reduction occurred on young islands. We also found evidence of migration among old islands (mostly from south to north), while it appears that there have been very few migration events between old and young islands. These differences could be due to the fact that young islands tend to be geographically isolated and support smaller populations that began a shorter time ago from limited founders. The P. boninensis populations on the Volcano Islands are interesting from an evolutionary perspective as they constitute a classic example of the early stages of progressive colonization on oceanic islands with small effective population sizes and low genetic diversity.

The Bonin Islands are endowed with endemic species. However, these species are at risk of extinction because of the exuberance of invasive alien plants. Therefore, native plant species should be revegetated after eradicating alien plants. We investigated the genetic variation of Terminalia catappa populations in the Bonin Islands by using nuclear (n) microsatellites (simple sequence repeats [SSRs]) and chloroplast (cp) DNA. No significant differences were observed in the genetic diversity of nSSRs among 22 populations. However, recent bottlenecks were detected in three populations on the Chichijima Island group. nSSR variation and cpDNA haplotypes suggested the presence of two genetically distinct groups in the Mukojima and Chichijima Island groups and the Hahajima Island group. A similar genetic structure was observed in plants and animals in the Bonin Islands. Populations on the three islands, which were separated from other islands in each island group when the water depth was 50-m lower than the present level, were dominated by unique nSSRs clusters, suggesting that historical changes in island connections during the Pleistocene era affected genetic substructuring. These results suggested that different factors contributed to the genetic structure of T. catappa on different geographic scales. At the whole-island level, the genetic structure was determined by long-distance seed dispersal by ocean currents. At the island-group level, the genetic structure was determined by historical changes in island connections caused by changes in the sea level due to glacial–interglacial transition. These findings would help in establishing transplantation zone borders for revegetating T. catappa on the Bonin Islands.

A new X-ray tube using a ring-shaped emitter as a field emission electron source has been developed. By using a ring shaped cathode, X-rays can be extracted along the axial direction through the central hole. This cylindrically symmetrical design allows for the tube to be arranged in the axial direction with the high voltage target at one end and the X-ray beam at the other. The newly developed X-ray tube can operate at a tube voltage of more than 100 kV and at a tube current of more than 4 mA, and can be used for irradiation experiments with an irradiation dose range from mGy up to kGy. The X-ray tube can be used immediately after turning on (i.e. there is no stand-by time). In the experimental model, we demonstrated stable electron emission at a tube voltage of 100 kV and at a tube current of 4 mA during a 560 h continuous test.

Since floras of oceanic islands are distinct from those of the closest continents, islands can serve as useful systems for understanding the evolution of host specificity during speciation of parasitic plants. Orobanche boninsimae (Orobanchaceae) is a holoparasitic plant species endemic to the isolated Bonin (Ogasawara) Islands; previous observations suggested several possible host species for O. boninsimae. In this study we sought to provide more definitive identification of O. boninsimae host plants through DNA analyses of host plant roots. We investigated nine populations of O. boninsimae from Chichijima and Hahajima Islands and determined their hosts by DNA barcoding of the chloroplast trnH-psbA region. We determined that three endemic woody species, Ochrosia nakaiana (Apocynaceae), Melicope grisea (Rutaceae), and Melicope nishimurae (Rutaceae), and one exotic tree, Bischofia javanica (Phyllanthaceae), were host species of O. boninsimae. These three families are newly recorded as hosts for the genus Orobanche, suggesting that O. boninsimae might have developed these unique host specificities in the islands. In addition, we established that O. boninsimae parasitizes completely different species between the islands, even though all available host species of O. boninsimae execpt for M. nishimurae were commonly distributed throughout these islands. This result suggests that intraspecific differentiation for host preference and possibly cryptic speciation has occurred between isolated islands.

The electron emission properties of a coniferous carbon nano-structure (CCNS) based field emission electron gun have been measured. The CCNS was grown on a stainless steel substrate using chemical vapor deposition (CVD) and biased to about 50 kV. Stable, high-current-density electron emission (102 mA/cm 2 ) was measured continuously for more than 1300 h. This result compares favorably to printed and directly grown carbon nanotube (CNT) based emitters. A wide range of potential applications are foreseen for CCNS based electron emitters, such as high intensity X-ray sources.

Distyly rarely occurs on oceanic islands. Indeed, this form of polymorphism is absent on the Hawaiian Islands and in New Zealand. However, Psychotria homalosperma (Rubiaceae), which is endemic to the oceanic Bonin Islands of Japan, was presumed to maintain a distylous breeding system and floral morphology. We investigated the floral and reproductive characteristics of this species and examined incompatibility in self- and intramorph pollination. Psychotria homalosperma is morphologically and functionally distylous, based on findings with the examined populations, but its stigma and anther heights are not exactly reciprocal between the two morphs. This is the second example of distyly among the flora from the Bonin Islands, the other being the endemic P. boninensis. Both of these distylous species contrast with the Hawaiian Psychotria species, which have already become dioecious. The flowers of the long (L)-styled (pin) morph of the Bonin Islands plants are completely self- and intramorph incompatible, while the flowers of the short (S)-styled (thrum) morphs are partially intramorph compatible. The S-styled morph was more abundant in the examined populations from three islands of the archipelago, probably due to the existence of partial S–S intramorph compatibility.

Islands isolated by oceans that act as a geographical barrier for plant migration often possess high species endemism and have been deemed as a natural laboratory for studying species divergence. Fatsia Decne. & Planch. (Araliaceae), with three species, is one of the few plant genera absent in continents while exclusively spanning continental and oceanic islands. The nuclear ribosomal internal transcribed spacer (nrITS) phylogeny uncovered a pattern with reciprocal monophyly of Fatsia oligocarpella Koidz. (Bonin) and Fatsia polycarpa Hayata (Taiwan) vs. paraphyly of Fatsia japonica (Thunb.) Decne. & Planch. (Japan and Ryukyus), suggesting ancestry of the species in Japan and a likely temperate origin; whereas, lack of monophyly of all three allopatrically distributed species at chloroplast DNA (cpDNA) trnL–trnF spacer likely resulted from lineage sorting. In spite of the limited habitats for F. oligocarpella, unexpectedly high genetic variations in this species of oceanic islands were likely attributable to multiple colonizations and recurrent gene introgression. Biogeographical analyses suggested that Fatsia likely diverged via southward colonization in Bonin Islands and Taiwan during the late Pliocene to Pleistocene. Besides, Fatsia species with an allopatric distribution provide a perfect model for testing speciation modes of insular endemics. Nonzero gene flow between species was detected based on MIGRATE and STRUCTURE analyses of DNA sequences and microsatellite fingerprints, suggesting that allopatric speciation is less likely.

Electron energy loss (EEL) spectra of GeF4 have been measured with incident electrons at 100 eV for 5° scattering angle and at 30 eV for 30° scattering angle, while sweeping the energy loss over the range 7.0–18.0 eV. Low-lying excited triplet, singlet, valence, and Rydberg states are investigated and the assignments supported by quantum chemical ab initio calculations. This provides the first comprehensive investigation of all singlet and triplet excited electronic states of germanium tetrafluoride up to the first ionization energy. The Rydberg series converging to the (lowest) ionization energy limits of GeF4 are also identified according to the magnitude of the quantum defects (δ).

We report results on new absolute cross section measurements for electron impact excitation of the two lowest 3 s [ 3 / 2 ] 1 and 3 s ′ [ 1 / 2 ] 1 , optically-allowed electronic-state levels in neon. Those measurements were conducted at eight specific energies in the 20–300 eV energy range. The present results, at the integral cross section level, strongly support those from the recent large-scale B-spline R-matrix computations [O. Zatsarinny, K. Bartschat, Phys. Rev. A 86 (2012) 022717], and resolve a serious discrepancy that had existed between earlier experimental results and theory. Some discrepancies in the differential cross sections, at middle and backward angles, are however still noted.

Gene flow between populations in different environmental conditions can be limited due to divergent natural selection, thus promoting genetic differentiation. Elaeocarpus photiniifolia, an endemic tree species in the Bonin Islands, is distributed in two types of habitats, dry scrubs and mesic forests. We aim to elucidate the genetic differentiation in E. photiniifolia within and between islands and between the habitat types. We investigated genotypes of 639 individuals from 19 populations of E. photiniifolia and its closely-related E. sylvestris at 24 microsatellite loci derived from expressed sequence tags. The data revealed genetic differentiation (1) between E. photiniifolia and E. sylvestris (0.307 ≤ F ST ≤ 0.470), (2) between the E. photiniifolia populations of the Chichijima and Hahajima Island Groups in the Bonin Islands (0.033 ≤ F ST ≤ 0.121) and (3) between E. photiniifolia populations associated with dry scrubs and mesic forests in the Chichijima Island Group (0.005 ≤ F ST ≤ 0.071). Principal coordinate analysis and Bayesian clustering analysis also showed that genetically distinct groups were associated with the habitat types, and isolation by distance was not responsible for the genetic differentiation. These findings suggest that E. photiniifolia is divided into genetically differentiated groups associated with different environmental conditions in the Bonin Islands.

Here, we report elastic differential cross sections (DCSs) for electron scattering from water in the incident energy range of 2−100 eV. Furthermore, we present a complete study on the electronic excitation of the a3B1 and A1B1 states at electron impact energies of 15, 20, and 30 eV and in the scattering angle range of 10° − 130°. Integral cross sections (ICSs) are determined from the DCSs. Measuring elastic DCSs in various experimental conditions confirmed the reproducibility of the data. The present results agree with the data previously obtained from a conventional collimating tube gas source. Ambiguities associated with the unfolding procedure of the electron energy loss (EEL) spectra for the electronic excitations have been reduced by comparison against the EEL spectrum at high electron impact energy and for small scattering angle. The reliability of the extracted DCSs is improved significantly for optically forbidden contributions from the overlap of the a3B1 and A1B1 electronic states. The BEf-scaling model is also confirmed to produce the integral cross section for the optical allowed transition of the A1B1 state in the intermediate electron energy region above 15 eV.

Persea boninensis (Lauraceae) is an endemic tree species distributed throughout the Bonin Islands. It grows in a wide range of environments from dry to mesic forests, and has multiple flowering peaks that may correspond to different habitats on Chichijima Island of the Bonin Islands. We predicted that P. boninensis is differentiated into two groups with different habitats on these islands. We examined and compared the flowering phenology, morphology, and genetics of populations of species growing in dry and mesic forests. We also performed preliminary artificial crossing experiments. Based on our results, P. boninensis on the Chichijima Islands can be clearly divided into two genetic groups with different habitats and flowering times. Although the flowering time difference could act as an effective pre-zygotic isolation mechanism between the two groups, there was still a 1-month overlap in flowering time. Furthermore, our artificial crossing experiments between the two groups resulted in plants that set seeds. Therefore, there was no evidence of reproductive isolation after fertilization. Differences in flowering time as well as in growth habitat will have to occur to maintain genetic differentiation between the two groups of P. boninensis.

Hata K, Kato H & Kachi N (2012). Leaf litter of the invasive Casuarina equisetifolia decomposes at the same rate as that of native woody species on oceanic islands but releases more nitrogen. Weed Research52, 542–550. Summary We tested whether the decomposition rates and N loss of leaf litter of an alien invasive tree, Casuarina equisetifolia, are affected by litter traits and environmental conditions in the Ogasawara Islands in the north-western Pacific Ocean. In a field experiment, we compared mass loss and N loss of leaf litter among four treatments in a 2 × 2 design of forest type (native and C. equisetifolia) × litter type (native and C. equisetifolia). The dry weight of C. equisetifolia litter remaining at the end of the experiment was significantly less than that of the litter of native species in both forest types. The dry weight of decomposing litter at the C. equisetifolia sites was significantly less than that at native forest sites, regardless of litter type. The dry weight of C. equisetifolia litter at the C. equisetifolia sites was similar to that of the litter of native species at the native forest sites. The C. equisetifolia leaf litter was significantly greater in N content and rate of N loss than the litter of native species. Our results demonstrate that the decomposition rate of C. equisetifolia litter is affected by both litter type and the forest type of the invaded sites and suggest that litter decomposition of C. equisetifolia may alter the total N and N cycling in invaded forest ecosystems.

A total of 55 microsatellite loci were developed and characterized using four Pittosporum taxa endemic to the Ogasawara (Bonin) Islands, Japan: Pittosporum boninense var. boninense, P. boninense var. chichijimense, Pittosporum parvifolium var. parvifolium and P. parvifolium var. beecheyi. Transferability of these markers among the Ogasawara Pittosporum taxa as well as Pittosporum tobira was also evaluated. The number of alleles per locus ranged from 2 to 23 in P. boninense var. boninense, from 2 to 16 in P. boninense var. chichijimense, from 1 to 7 with in P. parvifolium var. parvifolium, and from 1 to 8 in P. parvifolium var. beecheyi. During cross-amplification tests, the majority of these loci were successfully amplified and showed moderate to high levels of genetic variation. The markers described here could be used to achieve a more accurate determination of genetic diversity and genetic structure of the taxa from which they were derived.

We investigated the effects of litter accumulation by an alien tree, Casuarina equisetifolia, on the germination and seedling establishment of Rhaphiolepis wrightiana, a shrub native to the Ogasawara (Bonin) Islands, in the northwestern Pacific Ocean, in a field experiment. We compared the emergence of seedlings in forests dominated by C. equisetifolia with that in native forests, with and without litter removal. More than 75% of seedlings emerged during a year except at the C. equisetifolia sites with litter removal (approximately 45%). Thus, seeds of R. wrightiana can germinate under C. equisetifolia if they are dispersed on the ground.

We report absolute differential and integral cross-sections for excitation of the six lowest lying electronic states in water. The incident electron energy for this study was 15 eV and the scattered electron angular range, for the differential cross-section measurements, was 10 − 90 ° . Where possible comparison of the present cross-sections with the corresponding results from theory is made, the level of agreement between them being found to be somewhat marginal.

Twelve microsatellite loci were isolated and characterized for Melicope quadrilocularis, an insular endemic tree species of the Bonin Islands. The observed number of alleles at each locus ranged from 1 to 18. The range of expected heterozygosity was 0.0000–0.9445. The inter-specific applicability of these loci was evaluated by analyzing two other endemic species and one endemic variety of Melicope that are also distributed on the Bonin Islands. All primer pairs for the 12 loci tested successfully amplified the loci in all taxa, except for primers for four loci in M. nishimurae.

This research examines a master-slave control system for a tele-operation construction robot. This system is comprised of two joysticks on the master side, which are used to perform the object operation from a remote location, and a robot arm with four degrees of freedom consisting of a fork glove, swing, boom, and arm on the slave side. The authors previously proposed a control method that gives the operator a realistic feeling of the force generated by the construction robot independent of the characteristics of the object being manipulated using the velocity-drive force characteristics of the actuator. However, that research did not reach a stage in which operability could be evaluated adequately when the control method was adapted to actual tasks. Due to the high adaptability of human subjects, there are cases in which adequate evaluation is difficult if only work efficiency is considered. Therefore, an evaluation that includes the mental strain on the operator is necessary. We believe that alleviating this mental strain can contribute to improved efficiency and safety in tele-operation work. In this study, we evaluated operability when this control method is adapted to an actual task, based on work efficiency, indexes expressing the danger level of an operation, and measurement of mental strain using NASA-TLX, and we verified the effectiveness of the control method.

International audience; In this contribution we probe BF3 low-lying excited singlet states measured at 100 eV, 2.8° scattering angle and triplet states at 40 eV, 40° scattering angle, while sweeping the energy loss over the range 10.0-20.0 eV. The electronic state spectroscopy has been investigated and the assignments supported by quantum chemical calculations. This provides the first comprehensive investigation of all singlet and triplet excited electronic states of boron trifluoride up to the first ionization potential. A generalized oscillator strength analysis is employed to derive oscillator strength f0 value and integral cross sections (ICSs) from the corresponding differential cross sections (DCSs). The f0 value is compared with the optical oscillator strength (OOS) from photoabsorption, and the unscaled Born ICSs are then compared with relevant energy and binary-encounter and f-scaled Born cross section (BEf-scaling) results determined as a part of this investigation. The lowest n members of the Rydberg series have been assigned as converging to the lowest ionization energy limits of boron trifluoride and classified according to the magnitude of the quantum defects (δ).

Dystaenia (Apiaceae) consists of two species, one distributed in Japan (D. ibukiensis), and the other endemic to Ullung Island, Korea (D. takesimana). In comparison with representative outgroup taxa in Ligusticum, Seseli, Angelica, and Osmorhiza, Dystaenia is shown to be monophyletic based on sequences from chloroplast trnL-F intron and spacer regions confirming previously published results using ITS sequences. Loss of one large part of trn L-F in D. takesimana strongly suggests that this species evolved from D. ibukiensis rather than the reverse. AFLP analysis within and among twelve populations (six from each species; total 126 individuals) using three primer combinations reveals 130 reliable fragments. Neighbour-joining analysis shows the two species to be distinct populational systems. Levels of overall genetic variation as measured by Shannon Diversity are significantly higher in D. takesimana. Geographic structuring of genetic variation occurs within D. ibukiensis but not within D. takesimana, suggesting that the Ullung species exists as a single population. It is hypothesised that after a founder-effect reduction of genetic variation, anagenetic speciation may have occurred in D. takesimana by gradual morphological divergence accompanied by accumulation of genetic variation through mutation, recombination and drift.

Two woody Hibiscus species co-occur in the Bonin Islands of the northwestern Pacific Ocean: Hibiscus glaber Matsum. is endemic to the islands, and its putative ancestral species, Hibiscus tiliaceus L., is widely distributed in coastal areas of the tropics and subtropics. To infer isolating mechanisms that led to speciation of H. glaber and the processes that resulted in co-occurrence of the two closely related species on the Bonin Islands, we conducted molecular phylogenetic analyses on chloroplast DNA (cpDNA) sequences. Materials collected from a wide area of the Pacific and Indian Oceans were used, and two closely related species, Hibiscus hamabo Siebold Zucc. and Hibiscus macrophyllus Roxb., were also included in the analyses. The constructed tree suggested that H. glaber has been derived from H. tiliaceus, and that most of the modern Bonin populations of H. tiliaceus did not share most recent ancestry with H. glaber. Geographic isolation appears to be the most important mechanism in the speciation of H. glaber. The co-occurrence of the two species can be attributed to multiple migrations of different lineages into the islands. While a wide and overlapping geographical distribution of haplotypes was found in H. tiliaceus, localized geographical distribution of haplotypes was detected in H. glaber. It is hypothesized that a shift to inland habitats may have affected the mode of seed dispersal from ocean currents to gravity and hence resulted in geographical structuring of H. glaber haplotypes.

We propose a master-slave teleoperated construction robot consisting of an excavator as the construction robot and two joysticks for operating the robot remotely. A fork glove on the front of the excavator grasps objects. The slave corresponds to the fork glove and the master to joysticks used by an operator In such remote control, the operator needs a realistic ""feel"" of force from feedback from the fork glove. To attain effective feedback, as reported previously, we proposed variable-gain symmetric-position, but found the disadvantage that the operator could not get a realistic feel when grasping a soft object at a comparatively slow velocity. We propose an improvement to overcome this problem.

Genetically engineering strategies have been applied to obtain the designed proteins [GGAGSGYGGGYGHGYGSDGG(GAGAGS)3]n of varying chain lengths (n=2,4 or 6); SLP2, SLP4, and SLP6, respectively. The amino acid sequence of the monomeric unit represents the incorporation of the consensus repeat sequences of the glycine-rich region of Samia cynthia ricini followed by the repetitive crystalline region of Bombyx mori silk fibroins. The oligonucleotides were designed to encode the desired monomeric unit of silk-like hybrid proteins, which were then polymerised and expressed in Escherichi coli system. The monomer, SLP1, was synthesized chemically using solid phase method. The recombinant proteins were identified by N-terminal amino-acid sequencing and Western blotting. The structural characterizations of SLP1 and SLP6 samples were performed using 13C CP/MAS NMR in the solid state. The structure of SLP1 in the solid state was distorted .BETA.-turn by judging from the chemical shift and line shape of the C.BETA. carbon of Ala residue, and the structural transition from distorted .BETA.-turn to .BETA.-sheet occurred partially in SLP6. The solution structure was studied in hexafluoro-2-propanol (HFIP) using CD method. Although both samples, SLP1 and SLP6, showed indication of the ordered structures, marked change in the band intensities was observed between two CD spectra. Especially. the CD pattern of SLP6 is in agreement with the pattern with right-handed 310-helical conformation. (author abst.)

This study deals with a calculation method for the forward kinematics of a 3 DOF parallel link manipulator. As a method for such a calculation, up to the present, the Newton method, or Newton-Raphson method alternatively, has been generally used. Nevertheless, this method is difficult to apply to on-line control systems, since it requires significant computation time and a large capacity of computer memory for calculations. In this study, therefore, a new algorithm for calculating forward kinematics is proposed. Fundamentally, the algorithm consists of two processes. The first is to calculate in a very short time an approximate solution of the kinematics. The second is to compensate the approximate solution in order to obtain the accurate one. It was confirmed that the computation time for the new algorithm was decreased to as little as 1/69-1/81 that for the Newton method. It was also confirmed experimentally that the algorithm was successfully applicable to an on-line control system.

This study deals with a master-slave system of a tele-operated construction robot. The system consists of an excavator as the construction robot, and two joysticks for operating the robot from a remote place. A fork glove is equipped with the front end of the excavator as a hand for grasping task objects. The master and the slave in this system correspond to, respectively, the fork glove and the joysticks controlled by an operator. In such a remote control system, the operator needs to feel a realistic sense of task force which is brought about from a feedback force of the fork glove. In order to attain an effective feedback of the task force, in the previous report of this study, a control method called a variable-gain symmetric-position was proposed. After that, however, a weak point was found in this method. Namely, the operator was not able to feel a realistic sense of the task force when he was grasping a soft object in comparatively a slow velocity. In the present report, therefore, for overcoming this problem, an improved method of control in comparison with the previous method is proposed.

We have measured the emission stability of a coniferous carbon nano-structure (CCNS) field emission electron source. Stable emission over the 1274 h measurement was observed at an emission current density of 20 mA·cm−2. The CCNS emitter can generate an emission current of more than 10 mA making it a practical choice for many applications requiring high electron current. For example, we are currently developing a CCNS based electron gun for electron accelerators and a portable X-ray source. Recent progress on both these applications is presented.