At-sea experiment of adaptive time-reversal multiuser communication in the deep ocean

An at-sea experiment of multiuser communication in deep water using adaptive time reversal was carried out. In the experiment, two sources and a 20-channel receiver array were deployed at the range of 30 km in an area of 1500-2000 m water depth. One of the sources was moored and the other was suspended at various depths. For processing signals actually transmitted from two sources, it was demonstrated that adaptive time reversal could cancel multiuser interference independently of relative source positions. Additionally, for a more detailed investigation, the analysis of multiuser test signals by synthesizing signals from different depths was performed. As a result, especially in the case of adjacent sources, adaptive time reversal significantly suppressed crosstalk.http://www.godac.jamstec.go.jp/darwin/cruise/kaiyo/ky15-01/

Therapeutic effect of aged garlic extract on gingivitis in dogs

Periodontal disease is one of the most common dental health problems in dogs. Clinical studies in humans have shown that aged garlic extract (AGE), which contains stable and water-soluble sulfur-containing bioactive compounds, improves the symptoms of periodontal diseases. Our previous study demonstrated that oral administration of AGE in healthy Beagle dogs at 90 mg/kg/day for 12 weeks had no adverse effects such as hemolytic anemia, which is well known to occur as a result of ingestion of Allium species, including onions and garlic, in dogs. However, the therapeutic potential of AGE in canine periodontal disease remains unclear. Accordingly, we investigated the therapeutic effects of AGE in Beagle dogs with mild gingivitis. Feeding 18 mg/kg/day of AGE for 8 weeks resulted in the improvement of gingival index score, level of volatile sulfur compounds in exhaled air, and enzyme activity of periodontal pathogens without any adverse effects on clinical signs and hematological and serum biochemical parameters. Moreover, AGE increased the concentration of salivary cathelicidin, an antimicrobial peptide that contributes to the oral innate immune response. These results suggest that AGE could be a potential therapeutic agent for canine gingivitis

Experimental study on multiple-input/multiple-output communication with time reversal in deep ocean

Multiple-input/multiple-output (MIMO) communication using adaptive time reversal is discussed comparing with orthogonal frequency division multiplexing (OFDM) with simulated MIMO test signals by synthesizing experimental data in deep ocean. The experiment was executed in 1,100-m-depth area at the range of 10 km with the bandwidth of 500 +/- 50 Hz. Although time variance is not included in analysis of OFDM, it is impossible to increase MIMO channels with OFDM. In the meantime, with adaptive time reversal, it is possible to achieve 8 x 20 and 6 x 20 MIMO communication with binary phase shift keying (BPSK) and quadrature phase shift keying (QPSK), respectively, in spite of time variance and input SNRs degradation due to synthesizing signals. Thus, it is demonstrated that adaptive time reversal has much better performance than OFDM in MIMO underwater acoustic communication.http://www.godac.jamstec.go.jp/darwin/cruise/kaiyo/ky15-15/

Recent Results from LHD Experiment with Emphasis on Relation to Theory from Experimentalist’s View

he Large Helical Device (LHD) has been extending an operational regime of net-current free plasmas towardsthe fusion relevant condition with taking advantage of a net current-free heliotron concept and employing a superconducting coil system. Heating capability has exceeded 10 MW and the central ion and electron temperatureshave reached 7 and 10 keV, respectively. The maximum value of β and pulse length have been extended to 3.2% and 150 s, respectively. Many encouraging physical findings have been obtained. Topics from recent experiments, which should be emphasized from the aspect of theoretical approaches, are reviewed. Those are (1) Prominent features in the inward shifted configuration, i.e., mitigation of an ideal interchange mode in the configuration with magnetic hill, and confinement improvement due to suppression of both anomalous and neoclassical transport, (2) Demonstration ofbifurcation of radial electric field and associated formation of an internal transport barrier, and (3) Dynamics of magnetic islands and clarification of the role of separatrix

Experimental Investigation of the Influence of Moisture on the Bond Behavior of FRP to Concrete Interfaces

The effects of moisture on the initial and long-term bonding behavior of fibre reinforced polymer (FRP) sheets-to-concrete interfaces have been investigated by means of a two-year experimental exposure program. The research is focused on the effects of 1) moisture at the time of FRP installation, in this paper termed "construction moisture," consisting of concrete substratum surface moisture and external air moisture, and 2) moisture, in this paper termed "service moisture," which normally varies throughout the service life of concrete. Concrete beams with FRP bonded to their soffits were prepared. Before bonding, concrete substrates were pre-conditioned with different moisture contents and treated with different primers. The FRP bonded concrete beams were then cured under different humidity conditions, before being subjected to combined wet/dry and thermal cycling regimes to accelerate the exposure effects. Adhesives with different elastic modulus were used to investigate the long-term durability of each adhesive, when subjected to accelerated wet/dry cycling. Pull-off tests and bending tests were conducted at the beginning of the cycling and then again, after 8 months, 14 months and 2 years of exposure so as to evaluate the tensile and shear performance of the FRP-to-concrete interfaces. It was found that the effect of the concrete substrate moisture content on short-term interfacial bond performance could be eliminated if an appropriate primer was used. All FRP-to-concrete bonded joints failed at the interface between the primer and concrete after exposure while those not exposed usually failed within the concrete substrate. After exposure to an environment of accelerated wet/dry cycles, it was also found that the interfacial tensile bond strength degraded asymptotically with the exposure time while the flexural capacity of the FRP sheet bonded plain concrete beams even increased. The mechanism behind the above, which is an apparently contradictory phenomenon, is discussed

Aureobasidium pullulans produced β-glucan is effective to enhance Kurosengoku soybean extract induced Thrombospondin-1 expression

Black yeast, Aureobasidium pullulans is extracellularly produced β-(1,3), (1,6)-D-glucan (β-glucan) under certain conditions. In this study, using Glycine max cv. Kurosengoku (Kurosengoku soybeans), the production of β-glucan through fermentation of A. pullulans was evaluated, and the effects of A. pullulans cultured fluid (AP-CF) containing β-glucan made with Kurosengoku soybeans (kAP-CF) on a human monocyte derived cell line, Mono Mac 6 cells were investigated. Concentration of β-glucan in kAP-CF reached the same level as normal AP-CF. An anti-angiogenic protein, Thrombospondin-1 (THBS1) was effectively induced after the stimulation with kAP-CF for comparison with AP-CF. The THBS1 is also induced after stimulation with hot water extract of Kurosengoku soybeans (KS-E), while the combined stimulation of β-glucan with KS-E more effectively induced THBS1 than that with KS-E alone. These results suggest effects of A. pullulans-produced β-glucan on the enhancement of Kurosengoku soybean-induced THBS1 expression