31 research outputs found

    Dimensional Stability, Decay Resistance, and Mechanical Properties of Veneer-Faced Low-Density Particleboards Made From Acetylated Wood

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    Veneer-faced low-density particleboards were made using four combinations of control and acetylated veneers and particles. These boards were tested for dimensional stability in both liquid water and water vapor, for decay resistance in standard soil-block tests with Tyromyces palustris and Trametes versicolor, for strength losses during attack by T. palustris, and for mechanical strength in bending-creep and mechanical tests. Boards made from acetylated veneers and acetylated core particles showed excellent dimensional stability in both liquid water and humidity tests and were resistant to attack by both fungi in an 8-week soil-block test. During the 150-day bending-creep test, the totally acetylated boards showed no strength or weight loss during exposure to T. palustris. Modulus of elasticity and modulus of rupture were slightly reduced for totally acetylated boards compared to boards with control veneers and control particles, and internal bond strength was reduced by about 30%. Screw-holding capacity of the totally acetylated boards and boards with control veneers and particles was essentially the same

    Spiral Structure in WZ Sagittae around the 2001 Outburst Maximum

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    Intermediate resolution phase-resolved spectra of WZ Sge were obtained on five consecutive nights (July 23 -- 27) covering the initial stage of the 2001 superoutburst. Double-peaked emission lines of He\textsc{II} at 4686 \AA, which were absent on July 23, emerged on July 24 together with emission lines of C\textsc{III} / N\textsc{III} Bowen blend. Analyses of the He\textsc{II} emission lines using the Doppler tomography revealed an asymmetric spiral structure on the accretion disk. This finding demonstrates that spiral shocks with a very short orbital period can arise during the initial stage of an outburst and may be present in all SU UMa stars.Comment: 5 pages, 8 figures, accepted for publication in PAS

    A low-frequency IL4R locus variant in Japanese patients with intravenous immunoglobulin therapy-unresponsive Kawasaki disease

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    Background: Kawasaki disease (KD) is a systemic vasculitis which may be associated with coronary artery aneurysms. A notable risk factor for the development of coronary artery aneurysms is resistance to intravenous immunoglobulin (IVIG) therapy, which comprises standard treatment for the acute phase of KD. The cause of IVIG resistance in KD is largely unknown; however, the contribution of genetic factors, especially variants in immune-related genes, has been suspected. Methods: To explore genetic variants related to IVIG-unresponsiveness, we designated KD patients who did not respond to both first and second courses of IVIG therapy as IVIG-unresponsive patients. Using genomic DNA from 30 IVIG-unresponsive KD patients, we performed pooled genome sequencing targeting 39 immune-related cytokine receptor genes. Results: The single nucleotide variant (SNV), rs563535954 (located in the IL4R locus), was concentrated in IVIG-unresponsive KD patients. Individual genotyping showed that the minor allele of rs563535954 was present in 4/33 patients with IVIG-unresponsive KD, compared with 20/1063 individuals in the Japanese genome variation database (odds ratio = 7.19, 95% confidence interval 2.43-21.47). Furthermore, the minor allele of rs563535954 was absent in 42 KD patients who responded to IVIG treatment (P = 0.0337), indicating that a low-frequency variant, rs563535954, is associated with IVIG-unresponsiveness in KD patients. Although rs563535954 is located in the 3'-untranslated region of IL4R, there was no alternation in IL4R expression associated with the mior allele of rs563535954. However, IVIG-unresponsive patients that exhibited the minor allele of rs563535954 tended to be classified into the low-risk group (based on previously reported risk scores) for prediction of IVIG-resistance. Therefore, IVIG-unresponsiveness associated with the minor allele of rs563535954 might differ from IVIG-unresponsiveness associated with previous risk factors used to evaluate IVIG-unresponsiveness in KD. Conclusion: These findings suggest that the SNV rs563535954 could serve as a predictive indicator of IVIG-unresponsiveness, thereby improving the sensitivity of risk scoring systems, and may aid in prevention of coronary artery lesions in KD patients.ArticlePEDIATRIC RHEUMATOLOGY.17:34(2019)journal articl

    Low- and Medium-Dispersion Spectropolarimetry of Nova V475 Sct (Nova Scuti 2003): Discovery of an Asymmetric High-Velocity Wind in a Moderately Fast Nova

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    We present low-resolution (R90R\sim 90) and medium-resolution (R2500R\sim 2500) spectropolarimetry of Nova V475 Sct with the HBS instrument, mounted on the 0.91-m telescope at the Okayama Astrophysical Observatory, and with FOCAS, mounted on the 8.2-m Subaru telescope. We estimated the interstellar polarization toward the nova from the steady continuum polarization components and Hα\alpha line emission components. After subtracting the interstellar polarization component from the observations, we found that the Hα\alpha emission seen on 2003 October 7 was clearly polarized. In the polarized flux spectrum, the Hα\alpha emission had a distinct red wing extending to +4900\sim +4900 km s1^{-1} and a shoulder around +3500+3500 km s1^{-1}, showing a constant position angle of linear polarization \theta_{\rm *}\simeq 155\arcdeg\pm 15\arcdeg. This suggests that the nova had an asymmetric outflow with a velocity of vwind3500v_{\rm wind}\simeq 3500 km s1^{-1} or more, which is six times higher than the expansion velocity of the ionized shell at the same epoch. Such a high-velocity component has not previously been reported for a nova in the `moderately fast' speed class. Our observations suggest the occurrence of violent mass-loss activity in the nova binary system even during the common-envelope phase. The position angle of the polarization in the Hα\alpha wing is in good agreement with that of the continuum polarization found on 2003 September 26 (p0.4p_{\rm *}\simeq 0.4--0.6 %), which disappeared within the following 2 d. The uniformity of the PA between the continuum polarization and the wing polarization on October 7 suggests that the axis of the circumstellar asymmetry remained nearly constant during the period of our observations.Comment: 27 pages, 7 figures, accepted for publication in A

    Visual Cortical Prosthesis with a Geomagnetic Compass Restores Spatial Navigation in Blind Rats

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    SummaryAllocentric sense is one of the major components that underlie spatial navigation [1, 2]. In blind patients, the difficulty in spatial exploration is attributed, at least partly, to the deficit of absolute direction perception [3, 4]. In support of this notion, we announce that blind adult rats can perform spatial tasks normally when externally provided with real-time feedback of their head directions. Head-mountable microstimulators coupled with a digital geomagnetic compass were bilaterally implanted in the primary visual cortex of adult rats whose eyelids had been sutured. These “blind” rats were trained to seek food pellets in a T-shaped maze or a more complicated maze. Within tens of trials, they learned to manage the geomagnetic information source to solve the mazes. Their performance levels and navigation strategies were similar to those of normal sighted, intact rats. Thus, blind rats can recognize self-location through extrinsically provided stereotactic cues

    Dopamine receptor activation reorganizes neuronal ensembles during hippocampal sharp waves in vitro.

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    Hippocampal sharp wave (SW)/ripple complexes are thought to contribute to memory consolidation. Previous studies suggest that behavioral rewards facilitate SW occurrence in vivo. However, little is known about the precise mechanism underlying this enhancement. Here, we examined the effect of dopaminergic neuromodulation on spontaneously occurring SWs in acute hippocampal slices. Local field potentials were recorded from the CA1 region. A brief (1 min) treatment with dopamine led to a persistent increase in the event frequency and the magnitude of SWs. This effect lasted at least for our recording period of 45 min and did not occur in the presence of a dopamine D1/D5 receptor antagonist. Functional multineuron calcium imaging revealed that dopamine-induced SW augmentation was associated with an enriched repertoire of the firing patterns in SW events, whereas the overall tendency of individual neurons to participate in SWs and the mean number of cells participating in a single SW were maintained. Therefore, dopaminergic activation is likely to reorganize cell assemblies during SWs
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