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In LHD, real-time control of the incident EC wave polarization and quick response microwave bolometer for monitoring the stray radiations have been developed for efficient and safe operation of the high power and long pulse ECRH/ECCD. As a high power ECRH/ECCD application aiming for high density, ECRH has been demonstrated up to 85% of the cutoff density by the fundamental X-mode excitation in HFS with use of a horizontal port antenna located in LFS. As another application aiming for high temperature, the effect of the control of the rotational transform with use of the ECCD on the sustainment of the e-ITB is investigated. It has been suggested that higher local electron energy confinement time is obtained inside the e-ITB with placing the m/n = 2/1 magnetic island near the edge of the e-ITB compared to the case when the 2/1 island is vanished in the plasma.

Edge MHD instabilities with pressure collapse are found in relatively high beta and low magnetic Reynolds number regions with a magnetic axis torus outward-shifted configuration of the large helical device (LHD), and characteristics and onset conditions of the instability are investigated. The instability has a radial structure with an odd parity around the resonant surface, which is different from that of the interchange instability typically observed in the LHD. The onset condition dependence on the magnetic axis location shows that the onset beta increases as the magnetic axis location moves more torus inwardly, and the instability appears only in limited configurations where the magnetic axis is located between 3.65 and 3.775 m. In such configurations, the resonant surface location is close to an index of the plasma boundary. This fact suggests that the distance between the resonant surface location and the plasma boundary plays an important role in the onset, and a possibility that the instability is driven by an external mode. [ABSTRACT FROM AUTHOR]

In Madagascar, the house mouse (Mus musculus) is widely believed to have colonized with human activities and is now one of the most abundant rodents on the island. However, its genetic background at the genomic level remains unclear, and clarifying this would help us to infer the timing of introduction and route of migration. In this study, we determined the whole-genome sequences of five Madagascar house mice captured from an inland location in Madagascar. We examined the genetic background of samples by analyzing the mitochondrial and autosomal genomes. We confirmed that the mitochondrial genome lineages of collected samples formed a single clade placed at one of the most basal positions in the Mus musculus species. Autosomal genomic sequences revealed that these samples are most closely related to the subspecies M. m. castaneus (CAS), but also contain a genetic component of the subspecies M. m. domesticus (DOM). The signature of a strong population bottleneck 1,000-3,000 years ago was observed in both mitochondrial and autosomal genomic data. In a comparison with global samples of M. musculus, the Madagascar samples showed strong genetic affinity to many CAS samples across a wide range of Indian Ocean coastal and insular regions, with divergence time estimated as around 4,000 years ago. These findings support the proposition that the ancestors of these animals started to colonize the island with human agricultural activity and experienced a complex history during their establishment. [ABSTRACT FROM AUTHOR]

The large helical device (LHD) is the world largest helical system having all superconducting coils. After completion of LHD in 1998, six experimental campaigns have been carried out successfully. The maximum stored energy, central electron temperature, and volume averaged beta value are 1.16 MJ, 10 keV, and 3.2%, respectively. The confinement time of the LHD plasma appears to be equivalent to that of tokamaks. One of the most important missions for LHD is to prove steady-state operation, which is also significant to international thermonuclear experimental reactor (ITER) and to future fusion reactors. LHD is quite appropriate for this purpose based upon the beneficial feature of a helical system, that is, no necessity of the plasma current. So far, the plasma discharge duration was achieved up to 150 s. The plasma density was kept constant by feedback control of gas puffing with real time information of the line density. The issue for demonstrating steady-state operation is whether divertor function to control particle and heat flux is effective enough. Relevant to this, LHD diagnostics should be consistent with the following: 1) continuous operation of main diagnostics during long-pulse operation for feedback control and physics understanding; 2) measurement of fraction of H, He, and impurities in the plasma; 3) heat removal and measure against possible damage or surface erosion of diagnostic components inside of the vacuum chamber; 4) data acquisition system for handling real time data display and a huge amount of data. Although there are already some achievements on the above subjects, there remain still several issues to be resolved. On the other hand, the long-pulse operation of the plasma gives benefits to the diagnostics. For example, the polarizing angle of ECE emission can be changed during the discharge, and the intensity dependence on the polarizing angle has been obtained. The spatial scanning of the neutral particle analyzer and the spectrometer can supply the spatial profiles of the fast neutral particle flux and the specific impurity lines. In this paper, the present status of these issues and future plans are described. Index Terms--Fusion reactors, helical system, plasma measurements, stellarators.

To the Editor: Compelling evidence of genetically distinct hantaviruses (family Bunyaviridae) in multiple species of shrews and moles (order Soricomorpha, families Soricidae and Talpidae) across 4 continents (1-7) suggests that [...]

Murid and cricetid rodents were previously believed to be the principal reservoir hosts of hantaviruses. Recently, however, multiple newfound hantaviruses have been discovered in shrews, moles, and bats, suggesting a complex evolutionary history. Little is known about the genetic diversity and geographic distribution of the prototype shrew-borne hantavirus, Thottapalayam thottimvirus (TPMV), carried by the Asian house shrew (Suncus murinus), which is widespread in Asia, Africa, and the Middle East. Comparison of TPMV genomic sequences from two Asian house shrews captured in Myanmar and Pakistan with TPMV strains in GenBank revealed that the Myanmar TPMV strain (H2763) was closely related to the prototype TPMV strain (VRC66412) from India. In the L-segment tree, on the other hand, the Pakistan TPMV strain (PK3629) appeared to be the most divergent, followed by TPMV strains from Nepal, then the Indian-Myanmar strains, and finally TPMV strains from China. The Myanmar strain of TPMV showed sequence similarity of 79.3–96.1% at the nucleotide level, but the deduced amino acid sequences showed a high degree of conservation of more than 94% with TPMV strains from Nepal, India, Pakistan, and China. Cophylogenetic analysis of host cytochrome b and TPMV strains suggested that the Pakistan TPMV strain was mismatched. Phylogenetic trees, based on host cytochrome b and cytochrome c oxidase subunit I genes of mitochondrial DNA, and on host recombination activating gene 1 of nuclear DNA, suggested that the Asian house shrew and Asian highland shrew (Suncus montanus) comprised a species complex. Overall, the geographic-specific clustering of TPMV strains in Asian countries suggested local host-specific adaptation. Additional in-depth studies are warranted to ascertain if TPMV originated in Asian house shrews on the Indian subcontinent. [ABSTRACT FROM AUTHOR]

Shrew species have been proposed to utilize an echo‐based orientation system to obtain additional acoustic information while surveying their environments. This system has been supported by changes in vocal emission rates when shrews encounter different habitats of varying complexity, although detailed acoustic features in this system have not been reported. In this study, behavioral experiments were conducted using the long‐clawed shrew (Sorex unguiculatus) to assess this orientation system. Three experimental conditions were set, two of which contained obstacles. Short‐click, noisy, and different types of tonal calls in the audible‐to‐ultrasonic frequency range were recorded under all experimental conditions. The results indicated that shrews emit calls more frequently when they are facing obstacles or exploring the experimental environment. Shrews emitted clicks and several different types of tonal calls while exploring, and modified the use of different types of calls for varying behavior. Furthermore, shrews modified the dominant frequency and duration of squeak calls for different types of obstacles, that is, plants and acrylic barriers. The vocalizations emitted at short inter‐pulse intervals could not be observed when shrews approached these obstacles. These results are consistent with the echo‐based orientation hypothesis according to which shrews use a simple echo‐orientation system to obtain information from their surrounding environments, although further studies are needed to confirm this hypothesis. Sorex unguiculatus uses a simple, echo‐based orientation system that utilizes acoustic information to support their somatosensory responses, which is different from the more complex orientation systems found in bats and dolphins. [ABSTRACT FROM AUTHOR]

We calculate the heating power of the neutral beam injection (NBI) in a (β) = 4.8% high-beta discharge achieved in the Large Helical Device (LHD). We investigate the difference of the heating efficiency and the heating power profile with and without the re-entering fast ion effects. When the re-entering fast ion effects are taken into account, the heating efficiency of the co-injection of the NBI (co-NBI case) is improved and it is about 1.8 times larger than that without the re-entering effects. In contrast, the heating efficiency with the re-entering effects in the counter-injection of the NBI (ctr-NBI case) scarcely differs from that without the re-entering ones. We also study the re-entering fast ion effects on the transport properties in the LHD high-beta discharges. It is found that the tendency of the thermal conductivities on the beta value is not so much sensitive with and without the re-entering effects. In addition, we investigate the difference in the re-entering fast ion effects caused by the field strength and the magnetic configuration. In the co-NBI case, the heating efficiency with the re-entering effect was improved with a decrease in the field strength. In contrast, in the ctr-NBI case, it barely differs by changing the field strength. [ABSTRACT FROM AUTHOR]

Phylogenetical positions of Sorex specimens unassigned to species from Cheju Island, Korea. and S. caecutiens from southern Korean Peninsula were investigated based on full nucteotide sequences (1,140 bp) of the mitochondrial cytochrome b gene, comparing specimens of the S caecutiens/ shinto group from locations throughout its range+ In the phylogenetic tree obtained, S. caecutiens were separated into two main groups: Hokkaido and Continent-Sakhalin-Cheju clusters. Shrews from Cheju and Korean Peninsula were included in the latter cluster. Thus, we suggest that the shrew on Cheju Island should be ranked as S. caecutiens, although taxonomic description of the shrew has to be conducted elsewhere, The Cheju shrews formed a single sub-cluster while the peninsular shrews were not included in a single sub-cluster. The clustering of individuals in Continent-Sakhalin-Cheju cluster did not always reflect the geographical proximity of their capture locations. We interpret these findings as indicating ancestral isolation of a Hokkaido population and recent rapid range expansion of the modern population in Eurasian Continent-Sakhalin-Cheju. [ABSTRACT FROM AUTHOR]

Abstract Intraspecific phylogeny and genetic variation were investigated based on nucleotide sequences of the mitochondrial cytochrome b gene in six soricine shrew species, Sorex unguiculatus , S. caecutiens , S. shinto , S. gracillimus , S. minutissimus and S. hosonoi , collected primarily from northeastern Asia. Maximum likelihood trees and a phylogenetic network were generated to estimate intraspecific phylogenies. S. minutissimus showed high congruence between phylogenetic position and geographical origin and S. gracillimus showed low congruence. In contrast, there was no congruence between phylogeny and geography in S. unguiculatus and the S. caecutiens from Sakhalin-Eurasia. Positive correlation between genetic and geographical distances was found in S. minutissimus and S. gracillimus , but not in the other species (or regional populations). The results of the phylogenetic and genetic analyses suggest that S. minutissimus and S. gracillimus have occupied their present ranges for a longer time than the other species if we assume a stepping-stone model of population structure. In addition, there was no contradiction between the present investigations and the hypotheses of multiple immigration by S. gracillimus and a single immigration by S. unguiculatus into Hokkaido Island. It is proposed that these six northeastern Asian species experienced different historical processes of range expansion and dispersal despite the fact that some of them currently show similar patterns of distribution. [ABSTRACT FROM AUTHOR]

Various kinds of movable limiters are inserted into the plasma and effects on plasma performance are studied in the REPUTE-1 reversed-field pinch (RFP) device [Plasma Phys. Controlled Fusion 28, 805 (1986)]. The increases in one-turn loop voltage Vl and magnetic fluctuations with nearly constant value of ion temperature are found with an advance of movable limiters, and drastic increases in Vl are observed when the limiter is beyond a certain position. This Vl increase is discussed comparing with theories. The first pump limiter experiments in RFP are tried. Favorable effects such as reductions of Vl and impurity intensities are observed when the limiter head is inserted by ∼2 cm from the plasma edge. [ABSTRACT FROM AUTHOR]

Focuses on magnetic and velocity fluctuations in the REPUTE-1 reversed-field pinch (RFP). Measurement of velocity fluctuation in an RFP plasma; Estimation of the level of magnetohydrodynamic dynamo term from magnetic fluctuations at the surface correlation changes.

Structure of magnetohydrodynamic instabilities are observed by a tangentially viewing soft X-ray camera system in the large helical device. Displacement at the rational surface is estimated to be an even function at the mode rational surface by comparison with synthetic image assuming the displacement of the mode. [ABSTRACT FROM PUBLISHER]

A hot helical structure in low-aspect-ratio (A) reversed field pinch (RFP) is obtained with the soft X-ray (SXR) imaging technique. Tangential SXR imaging camera and high-speed camera system is applied to low-A RFP for studying quasi-single-helicity RFP state. The helical structure correlated with m = 1/n = 4 tearing mode is identified by means of a subtraction technique. [ABSTRACT FROM AUTHOR]

• Activity screening of Cuban endemic plants used as traditional medicines. • Discovery of an anti-inflammatory quinoid from a Cuban endemic plant. • Structure-activity relationship studies and stability analysis. • Monitoring of inflammatory cytokines in vitro and in vivo. • Relationship of anti-inflammatory activity and electrophilicity as a Michael acceptor. The Cuban endemic plant Jacaranda arborea (Bignoniaceae) has been traditionally used in folk medicine as an acaricide and for acne treatment. Two known quinoids, methyl (1-hydroxy-4-oxocyclohexa-2,5-dien-1-yl)acetate (jacaranone) (1) and its ethyl ester 2 were isolated from this species as anti-inflammatory substances. Compound 1 prominently inhibited the production of TNF-α in both LPS-treated macrophages and mice, with low toxicity. Structure-activity relationship studies revealed that the high electrophilicity of 1 as a Michael acceptor played an important role in these effects. Unlike in previous studies, such as those on antitumor, anti-oxidant, and anti-malarial activities, ester derivatives of 1 retained their potent anti-inflammatory activity. Our results suggest that jacaranones may target specific biomacromolecule(s) at lower concentrations than hitherto expected to exhibit potent activities. [ABSTRACT FROM AUTHOR]