Numerical study of air-entraining and submerged vortices in a pump sump

Numerical detection of harmful vortices in pump sumps, such as an air-entraining vortex (AEV) and a submerged vortex (SMV), is crucially important to develop the drain pump machinery. We performed numerical simulations of the benchmark experiments of the pump sump conducted by Matsui et al. (2006 and 2016) using the OpenFOAM and compared the simulation results with the experimental data considering the effects of turbulence model, grid density and detection method of the vortices. We studied the threshold of the gas-liquid volume fraction of the VOF method and the second invariant of velocity gradient tensor to identify AEV and SMV. The methods proposed in the present paper were found to be very effective for the detection of the vortices, and the simulation results by RANS with the SST k-omega model successfully reproduced the experimental data. LES with the Smagorinsky model, however, was sensitive to the grid system and difficult to reproduce the experimental data even for the finest grid system having 3.7 million cells in the present study

Expert consensus on hospitalization for assessment: a survey in Japan for a new forensic mental health system

<p>Abstract</p> <p>Background</p> <p>In Japan, hospitalization for the assessment of mentally disordered offenders under the Act on Medical Care and Treatment for the Persons Who Had Caused Serious Cases under the Condition of Insanity (the Medical Treatment and Supervision Act, or the MTS Act) has yet to be standardized.</p> <p>Methods</p> <p>We conducted a written survey that included a questionnaire regarding hospitalization for assessment; the questionnaire consisted of 335 options with 9 grades of validity for 60 clinical situations. The survey was mailed to 50 Japanese forensic mental health experts, and 42 responses were received.</p> <p>Results</p> <p>An expert consensus was established for 299 of the options. Regarding subjects requiring hospitalization for assessment, no consensus was reached on the indications for electroconvulsive therapy (ECT) or for confronting the offenders regarding their offensive behaviors.</p> <p>Conclusions</p> <p>The consensus regarding hospitalization for assessment and its associated problems were clarified. The consensus should be widely publicized among practitioners to ensure better management during the hospitalization of mentally disordered offenders for assessment.</p

Large-scale vortical structure detection using microphone array in a semiconductor single wafer spin cleaner

Fluctuating pressure (p’ ) of a large-scale vortical structure generated in a semiconductor single wafer spin cleaner was detected by using microphone array. Twelve microphones were installed on the exhaust cover under the rotating disk of the cleaner with their interval of 7.5° or 15°. Power spectrum densities (PSD) of p’ were compared with those of fluctuating velocity measured by PIV for various rotation angular velocities to identify fluctuations due to convection of the large-scale vortical structure. Good agreement of PSDs indicates that the large-scale structure could be detected by using microphone. Cross-correlation of p’ measured at different positions revealed that the large-scale structure convected to the downstream in the rotational direction of the disk. The convection speed was about 12 % of the angular velocity of the rotating disk. Number of the vortex in the large-scale structure was also evaluated from the time-series p’ data. Time-space contour map was made for p’ based on the data measured at the different angular position, and showed periodical swept strip patterns. Presences of the strip patterns indicate the pressure disturbances were stably convected to the downstream. From this time-space map, two-dimensional Fourier transform efficiently extracted the number of vortices in the large-scale structure

Periodical structure of vortices in a semiconductor single wafer spin cleaner

We experimentally and numerically investigated large-scale structures formed by vortices in a single wafer spin cleaner. The Q-criterion identified the vortices developed in the cleaner as the flow regions with positive second invariant of the velocity gradient tensor obtained by both the PIV and LES. The time-series two-components PIV data shows that small-vortices were clustered near and under the edge of the rotating disk and were periodically emanated from there to the housing wall of the cleaner. The emanation frequency was increased with increasing in the angular velocity of the rotating disk. Three-dimensional LES reveal that six longitudinal vortices were spirally developed from under the edge of the rotating disk to the housing wall. This structure stably rotated slower than the disk speed. Fourier analysis of the LES data agreed with that of the PIV data. This supports that the passages of the stable spiral vortices on the PIV measurement region resulted in the periodical emanation of the clustered small-vortices observed in the PIV. Such a very large-scale spiral structure will induce reattachment of contaminants on the wafer surface, and should be destructed for development of much higher efficient cleaner

Genetic Elucidation for Response of Flowering Time to Ambient Temperatures in Asian Rice Cultivars

Climate resilience of crops is critical for global food security. Understanding the genetic basis of plant responses to ambient environmental changes is key to developing resilient crops. To detect genetic factors that set flowering time according to seasonal temperature conditions, we evaluated differences of flowering time over years by using chromosome segment substitution lines (CSSLs) derived from japonica rice cultivars "Koshihikari" x "Khao Nam Jen", each with different robustness of flowering time to environmental fluctuations. The difference of flowering times in 9 years' field tests was large in "Khao Nam Jen" (36.7 days) but small in "Koshihikari" (9.9 days). Part of this difference was explained by two QTLs. A CSSL with a "Khao Nam Jen" segment on chromosome 11 showed 28.0 days' difference; this QTL would encode a novel flowering-time gene. Another CSSL with a segment from "Khao Nam Jen" in the region around Hd16 on chromosome 3 showed 23.4 days" difference. A near-isogenic line (NIL) for Hd16 showed 21.6 days' difference, suggesting Hd16 as a candidate for this QTL. RNA-seq analysis showed differential expression of several flowering-time genes between early and late flowering seasons. Low-temperature treatment at panicle initiation stage significantly delayed flowering in the CSSL and NIL compared with "Koshihikari". Our results unravel the molecular control of flowering time under ambient temperature fluctuations

Changes in the Collagen Binding Property of Human Plasma Fibronectin with Aging

We investigated changes in quality of plasma fibronectin with aging, especially in the interaction of fibronectin with collagen, using an enzyme-linked immunosorbent assay. When fibronectin isolated from the plasma of young people was compared with that from old people, the latter was found to bind poorly to gelatin, Type I and Type III collagens. No differences in molecular weight were detected between the two types of fibronectin by SDS-polyacrylamide gel electrophoresis

Natural Variation in the Flag Leaf Morphology of Rice Due to a Mutation of the NARROW LEAF 1 Gene in Oryza sativa L.

We investigated the natural variations in the flag leaf morphology of rice. We conducted a principal component analysis based on nine flag leaf morphology traits using 103 accessions from the National Institute of Agrobiological Sciences Core Collection. The first component explained 39% of total variance, and the variable with highest loading was the width of the flag leaf (WFL). A genome-wide association analysis of 102 diverse Japanese accessions revealed that marker RM6992 on chromosome 4 was highly associated with WFL. In analyses of progenies derived from a cross between Takanari and Akenohoshi, the most significant quantitative trait locus (QTL) for WFL was in a 10.3-kb region containing the NARROW LEAF 1 (NAL1) gene, located 0.4 Mb downstream of RM6992. Analyses of chromosomal segment substitution lines indicated that a mutation (G1509A single-nucleotide mutation, causing an R233H amino acid substitution in NAL1) was present at the QTL. This explained 13 and 20% of total variability in WFL and the distance between small vascular bundles, respectively. The mutation apparently occurred during rice domestication and spread into japonica, tropical japonica, and indica subgroups. Notably, one accession, Phulba, had a NAL1 allele encoding only the N-terminal, or one-fourth, of the wild-type peptide. Given that the Phulba allele and the histidine-type allele showed essentially the same phenotype, the histidine-type allele was regarded as malfunctional. The phenotypes of transgenic plants varied depending on the ratio of histidine-type alleles to arginine-type alleles, raising the possibility that H(233)-type products function differently from and compete with R(233)-type products

The Far-Infrared Surveyor (FIS) for AKARI

The Far-Infrared Surveyor (FIS) is one of two focal plane instruments on the AKARI satellite. FIS has four photometric bands at 65, 90, 140, and 160 um, and uses two kinds of array detectors. The FIS arrays and optics are designed to sweep the sky with high spatial resolution and redundancy. The actual scan width is more than eight arcmin, and the pixel pitch is matches the diffraction limit of the telescope. Derived point spread functions (PSFs) from observations of asteroids are similar to the optical model. Significant excesses, however, are clearly seen around tails of the PSFs, whose contributions are about 30% of the total power. All FIS functions are operating well in orbit, and its performance meets the laboratory characterizations, except for the two longer wavelength bands, which are not performing as well as characterized. Furthermore, the FIS has a spectroscopic capability using a Fourier transform spectrometer (FTS). Because the FTS takes advantage of the optics and detectors of the photometer, it can simultaneously make a spectral map. This paper summarizes the in-flight technical and operational performance of the FIS.Comment: 23 pages, 10 figures, and 2 tables. Accepted for publication in the AKARI special issue of the Publications of the Astronomical Society of Japa