Search

We study signal processing methods to realize ultra-high-density hard disk drives (HDDs). Among them, we have applied the neural network to improve decoding performance in low-density parity-check (LDPC) coding and iterative decoding in the shingled magnetic recording (SMR) system. In this study, we realize acceleration of the sum-product (SP) decoding by updating the decoding reliability of the SP decoding using the reliability of the recording sequence calculated by the neural network based on the parity check results. As a result, the proposed system achieved error-free with the fewest number of iterations in the SP decoder compared to our previous studies.

In F1 hybrids of Oryza sativa (Asian rice) and Oryza glaberrima (African rice), heterozygosity leads to a complete gamete abortion because of allelic conflict at each of the 13 hybrid sterility (HS) loci. We systematically produced 19 plants from the F1 hybrids of both the rice species by the anther culture (AC) method. Five of the 19 interspecific hybrid plants were partially fertile and able to produce seeds. Unlike ordinal doubled haploid plants resulting from AC, these regenerated plants showed various ploidy levels (diploid to pentaploid) and different zygosities (completely homozygous, completely heterozygous, and a combination). These properties were attributable to meiotic anomalies in the interspecific hybrid F1 plants. Examination of the genetic structures of the regenerated plants suggested meiotic non-reduction took place in the interspecific hybrid F1 plants. The centromeric regions in the regenerated plants revealed that the abnormal first and/or second divisions of meiosis, namely the first division restitution (FDR) and/or second division restitution (SDR), had occurred in the interspecific hybrid. Immunohistochemical observations also verified these phenomena. FDR and SDR occurrences at meiosis might strongly lead to the formation of diploid microspores. The results demonstrated that meiotic anomalies functioned as a reproductive barrier occurred before the HS genes acted in gamete of the interspecific hybrid. Although such meiotic anomalies are detrimental to pollen development, the early rescue of microspores carrying the diploid gamete resulted in the fertile regenerated plants. The five partially fertile plants carrying tetraploid genomes with heterozygous alleles of the HS loci produced fertile diploid pollens, implying that the diploid gametes circumvented the allelic conflicts at the HS loci. We also proposed how diploid male gametes avoid HS with the killer–protector model.

Abstract Background To investigate plant hybrid sterility, we studied interspecific hybrids of two cultivated rice species, Asian rice (Oryza sativa) and African rice (O. glaberrima). Male gametes of these hybrids display complete sterility owing to a dozen of hybrid sterility loci, termed HS loci, but this complicated genetic system remains poorly understood. Results Microspores from these interspecific hybrids form sterile pollen but are viable at the immature stage. Application of the anther culture (AC) method caused these immature microspores to induce callus. The segregation distortion of 11 among 13 known HS loci was assessed in the callus population. Using many individual calli, fine mapping of the HS loci was attempted based on heterozygotes produced from chromosome segment substitution lines (CSSLs). Transmission ratio distortion (TRD) from microspores was detected at 6 of 11 HS loci in the callus population. The fine mapping of S 1 and S 19 loci using CSSLs revealed precise distances of markers from the positions of HS loci exhibiting excessive TRD. Conclusions We demonstrated that AC to generate callus populations derived from immature microspores is a useful methodology for genetic study. The callus population facilitated detection of TRD at multiple HS loci and dramatically shortened the process for mapping hybrid sterility genes.

Limonium sinuatum (L.) Mill. (2n = 2x = 16) is a popular ornamental plant with dimorphism of pollen grains (type A and type B) and stigmas (papilla and cob-like). We applied polyploidy breeding to this species in order to introduce desirable traits. Tetraploid and mixoploid L. sinuatum plants were successfully obtained with oryzalin treatment of L. sinuatum ‘Early Blue’ seeds. All three tetraploids had increased leaf width, stomatal size, flower length, and pollen width compared to those of the diploid, and tetraploids had four germinal pores of pollen grains, whereas the diploid had three. All tetraploids had type A pollen grains and cob-like stigmas. Furthermore, the growth of cultivated tetraploid plants was slow, with later bolting and flowering times. Mixoploids Mixo-1 and Mixo-3 were estimated to be polyploidy periclinal chimeric plants consisting of a tetraploid L1 layer and diploid L2 layer, and Mixo-2 was estimated to be a polyploidy periclinal chimeric plant consisting of the diploid L1 layer and tetraploid L2 layer. Mixo-4 had tetraploid L1 and L2 layers. Mixoploids, except Mixo-4, had type A pollen grains and cob-like stigmas, whereas Mixo-4 had type B pollen grains and papilla stigmas. These polyploids will be useful as polyploidy breeding materials.

This paper examines conditions of social exclusion and attempts at social inclusion in Japan from a housing perspective. Companies, households and the government have previously supported housing in Japan. However, corporate welfare was withdrawn following the globalization of the economy from the 1990s onwards, support from families and communities declined due to a reduction in household size, and governmental housing support has shifted away from direct support. A reduction in income and unstable work left many people with unstable housing. Certain workers, such as foreigners performing dispatched labour, could not maintain continuous work under the influence of the Lehman Brothers’ bankruptcy in 2008. Household size has shrunk according to changes in the industrial structure, and the number of households that cannot sustain housing is increasing. Such vulnerable households—elderly people, the handicapped, low-income earners and single parents—can become excluded from the rental housing market. On the other hand, governmental measures are promoting local dwellings and maintaining the condition for a dwelling service. Activities, such as local community support of the homeless have been initiated by various Non-profit Organisations (NPOs) and NPO activities are increasingly exemplifying measures to achieve social inclusion.

We diagnosed leptospirosis in 2 patients exposed to southern flying squirrels imported from the United States to Japan. Patients worked with exotic animals in their company. Leptospira isolates from 1 patient and 5 of 10 squirrels at the company were genetically and serologically identical and were identified as Leptospira kirschneri.

Introduction Despite a decade of research into virtual stent deployment and the post- stenting aneurysmal hemodynamics, the hemodynamic factors which correlate with successful treatment remain inconclusive. We aimed to examine the differences in various post- treatment hemodynamic parameters between successfully and unsuccessfully treated cases, and to quantify the additional flow diversion achievable through stent compaction or insertion of a second stent. Methods A systematic review and meta- analysis were performed on eligible studies published from 2000 to 2019. We first classified cases according to treatment success (aneurysm occlusion) and then calculated the pooled standardized mean differences (SMD) of each available parameter to examine their association with clinical outcomes. Any additional flow diversion arising from the two common strategies for improving the stent wire density was quantified by pooling the results of such studies. Results We found that differences in the aneurysmal inflow rate (SMD -6.05, 95% CI -10.87 to -1.23, p=0.01) and energy loss (SMD -5.28, 95% CI -7.09 to -3.46, p<0.001) between the successfully and unsuccessfully treated groups were indicative of statistical significance, in contrast to wall shear stress (p=0.37), intra- aneurysmal average velocity (p=0.09), vortex core- line length (p=0.46), and shear rate (p=0.09). Compacting a single stent could achieve additional flow diversion comparable to that by dualstent implantation. Conclusions Inflow rate and energy loss have shown promise as identifiers to discriminate between successful and unsuccessful treatment, pending future research into their diagnostic performance to establish optimal cut- off values. [ABSTRACT FROM AUTHOR]

Background: Neuroendovascular therapy is now the choice for the management of many neurovascular pathologies, and physicians with endovascular skills are in high demand. In addition to the traditional method of practicing hand movements to learn skills, a new strategy of practicing eye movements to learn skills is also attracting attention. This preliminary study explored the differences in gaze behavior depending on experience with endovascular procedures to be facilitated in future skill training in neuroendovascular therapy. Methods: Four physicians with experience of 3-412 neuroendovascular procedures wore eye-tracking devices during coil embolization of swine cervical arteries. Gaze metrics with direct correlations to the expertise of endovascular procedures were explored. Results: Gaze metrics with a positive direct correlation to experience included the proportion of fixation durations (PFD) in the screen area and the native images. Those with a negative direct correlation included the PFD in the offscreen area and the roadmap images and the average fixation durations in the off-screen and coil areas. During the parent artery occlusion procedure with detachable coils, more experienced operators preferred to look at native images rather than roadmap images and that less experienced operators tended to look down at their hands more frequently. Conclusion: This preliminary study demonstrated the feasibility of eye tracking to identify the differences in gaze behavior depending on the experience of endovascular procedures and may guide future eye-tracking studies in neuroendovascular therapy. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the influence of the writing and reading intertrack interferences (ITIs) in terms of bit aspect ratio (BAR) in shingled magnetic recording by computer simulation using a read/write model which consists of a writing process based on Stoner-Wohlfarth switching asteroid by a one-side shielded isosceles triangular write head and a reading process by an around shielded read head for a discrete Voronoi medium model. The results show that BAR should be 3 to reduce the influence of writing and reading ITIs, media noise, and additive white Gaussian noise in an assumed areal density of 4.61Tbpsi. [ABSTRACT FROM AUTHOR]

In the extraction chromatography system, accumulation of hydrogen gas in the chromatography column is suspected to lead to fire or explosion. In order to prevent the hazardous accidents, it is necessary to evaluate behaviors of gas radiolytically generated inside the column. In this study, behaviors of gas inside the extraction chromatography column were investigated through experiments and Computation Fluid Dynamics (CFD) simulation. N2 gas once accumulated as bubbles in the packed bed was hardly discharged by the flow of mobile phase. However, the CFD simulation and X-ray imaging on g-ray irradiated column revealed that during operation the hydrogen gas generated in the column was dissolved into the mobile phase without accumulation and discharged. [ABSTRACT FROM AUTHOR]

The nature of the inner coordination sphere of In3+ present in both the organic and aqueous solutions during the solvent extraction of In3+ from an aqueous HCl solution with tri-n-octyl amine (TOA) was investigated by In K-edge XAFS. This information was then used to clarify the details of the extraction properties of indium chloride anion complexes with TOA. In aqueous HCl solution (0.1-10 M), In3+ exists as octahedral anion complexes, [InCln(H2O)6-n]3-n (n = 4); the [InCl6]3- complex is dominant at 10 M HCl. The extraction of In3+ from HCl solution with TOA was performed using two kinds of diluents: nitrobenzene (NB) or n-dodecane (DD), which contained 20 vol% of 2-ethylhexanol as an additive. The stoichiometric composition of the extracted complexes, which is estimated from the distribution ratios of In3+, is affected by the diluents and the HCl concentration of the aqueous phase; the apparent values of TOA/In3+ in the extracted complex are 3 for DD-1 M HCl (diluent-aqueous phase) and DD-5 M HCl, 2 for NB-1 M HCl and NB-5 M HCl, and 1 for NB-10 M HCl. The EXAFS analysis of these extracted complexes shows that the In3+ has ~4 Cl- at ~2.336 Å and no H2O in the inner coordination sphere; additionally, the shape of the XANES suggests that their coordination geometry is tetrahedral. Therefore, the same tetrahedral [InCl4]- complex is formed during the extraction in spite of the variation in the stoichiometric composition (TOA/In3+ = 1-3) of the extracted complexes. [ABSTRACT FROM AUTHOR]

Abstract  The single-strand conformation polymorphism (SSCP) procedure has been applied in routine testing for hereditary diseases. Temperature, running buffer, gel composition, and fragment length can influence its sensitivity. Mutation detection in the clinical setting depends on the development of automated technology, especially for large genes, such as the dihydropyrimidine dehydrogenase (DPYD) gene, which codes the initial, rate-limiting enzyme in the catabolism of 5-fluorouracil (5FU). The authors have optimized the condition of SSCP with an automated system (GenePhor system, GE Healthcare UK Ltd.) to screen genetic polymorphisms in the DPYD gene. The efficiency of the method was evaluated using 21 positive controls (DNA samples with polymorphisms in the DPYD gene, previously characterized) and DNA samples from 35 Japanese. Results showed that the use of three different running buffers (pH 7.4, 8.3, and 9.0) in combination with other optimized conditions (10% polyacrylamide gel, 60–90 min at constant 900 V at 5�C) resulted in a high polymorphism detection rate (95.3%), which was considered appropriate for routine screening. Therefore, this strategy could be useful for pharmacogenetic studies on 5FU. [ABSTRACT FROM AUTHOR]

Recently, the demand for higher density digital recording has been increasing steadily. In this article, focusing on digital magnetic recording devices, such as magnetic disks and digital VTRs, a signal processing technique for achieving higher densities is described. First, the partial response system, Viterbi decoding method, and partial response maximum likelihood (PRML) system are described in detail. Next, various signal processing methods extensively studied in recent years for longitudinal magnetic recording are described. Recent research trends in signal processing methods responsive to nonlinear distortions, with allowance for nonlinear distortions, such as partial erasure as factors promoting error rate degradation in high-density recording, are discussed. The performances of various methods are compared. A signal processing method for vertical magnetic recording expected to be a promising technique for future high density recording is described. ©1999 Scripta Technica, Electron Comm Jpn Pt 2, 82(6): 25–45, 1999 [ABSTRACT FROM AUTHOR]

A conventional 8/10 MSN code was constructed so as not to generate a quasi-catastrophic sequence in the decoder trellis diagram, and needing sliding block decoders. In this article, a new 8/10 MSN code is designed by using a periodically time-varying trellis diagram. The proposed code has an improved squared Euclidean distance distribution between PR output sequences and an improved number of paired codewords that have minimum squared free Euclidean distance decreases as compared with the conventional code. Further, this code can be decoded simply by referring codeword sequences corresponding to data sequences in a look-up table, needing no sliding block decoder. As a result, the proposed 8/10 MSN-coded PR4ML system can provide about 0.8 dB SNR gain over the conventional system at a bit error rate of 10–4 and a normalized linear density of 3. © 1999 Scripta Technica, Election Comm Jpn Pt 2, 82(3): 31–40, 1999 [ABSTRACT FROM AUTHOR]

Crystal damage induced in hexagonal SiC by cutting was characterized by transmission electron microscopy and Raman scattering. Wiresawing with loose abrasive (WSLA) induces stacking faults (SFs), dispersive triangular crystal disordered areas, and dislocation half-loop bundles. Wiresawing with fixed abrasive (WSFA) induces SFs, crystal disordered layers, and dislocation half-loop bundles. Electric discharge machining (EDM) predominantly forms silicon, carbon, and 3C-SiC by 6H-SiC decomposition. The mechanisms inducing crystal damage by slicing were discussed on the basis of characterization results. [ABSTRACT FROM AUTHOR]

We have studied the magnetic properties and the lattice structure of pure CeO2 irradiated with swift heavy ions. Experimental results showed that the ferromagnetism was induced at room temperature by 10 MeV I ion irradiation. The value of saturation magnetization increases with increasing the ion fluence and reaches a maximum value at about the fluence of 1.2 × 1013/cm2, and then decreases. The X-ray diffraction (XRD) spectra showed that the lattice parameter of CeO2 increases with increasing ion fluence. To examine the origin of the ferromagnetic state in CeO2, we compared the result for 10 MeV I ion irradiation with that for 200 MeV Xe ion irradiation. We also estimated the magnetic properties for CeO2 pellets annealed at 1273 K in a vacuum. From the experimental results, we concluded that oxygen vacancies, which are produced by electronic excitation process due to high energy ion beam, play an important role in the appearance of the ferromagnetic state in CeO2. [ABSTRACT FROM AUTHOR]

Organic-inorganic based conjugate materials are important in nanotechnology based on the high functionality and stable complex formation with target metal ions at optimum conditions. In this study, a new ligand immobilization based dual and tunable conjugate adsorbent was investigated under specific solution acidity for detection and removal of Co(II) and Cu(II) ions. In this detection system, notable color changes (intense π-π transition) and absorbance spectral intensity of the conjugate adsorbent for Co(II) and Cu(II) were observed at pH 8.0 and 5.2, respectively. Under the optimum conditions, the calibration graphs were the linear and detection limit which were 0.52 and 0.41 μg/L for Co(II) and Cu(II), respectively. The removal efficiency was carried out as a function of solution pH, initial metal ions concentration, and co-existing diverse ions. Sorption equilibrium was well fitted to Langmuir isotherms and determined sorption capacity was 205.33 and 199.20 mg/g for Co(II) and Cu(II), respectively. The adsorbent proved to have an efficient ability for continuous monitoring and removal of Co(II) and Cu(II) ions, even on-site and in situ chemical analyses. The adsorbent was eluted with dilute HCl acid and simultaneously regenerated into its original form. However, several cycles were reused with slight decrease in sorption capacity compared with the initial capacity. Therefore the conjugate adsorbent can be used as cost-effective materials and is a potential candidate for the selective detection and removal of Co(II) and Cu(II) ions from wastewater. The proposed adsorbent was compared with other materials and applied to the analysis and removal of Co(II) and Cu(II) ions from several water samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Conjugate materials can provide chemical functionality, enabling an assembly of the ligand complexation ability to metal ions that are important for applications, such as separation and removal devices. In this study, we developed ligand immobilized conjugate adsorbent for selective cesium (Cs) removal from wastewater. The adsorbent was synthesized by direct immobilization of dibenzo-24-crown-8 ether onto inorganic mesoporous silica. The effective parameters such as solution pH, contact time, initial Cs concentration and ionic strength of Na and K ion concentrations were evaluated and optimized systematically. This adsorbent was exhibited the high surface area-to-volume ratios and uniformly shaped pores in case cavities, and its active sites kept open functionality to taking up Cs. The obtained results revealed that adsorbent had higher selectivity toward Cs even in the presence of a high concentration of Na and K and this is probably due to the Cs-π interaction of the benzene ring. The proposed adsorbent was successfully applied for radioactive Cs removal to be used as the potential candidate in Fukushima nuclear wastewater treatment. The adsorbed Cs was eluted with suitable eluent and simultaneously regenerated into the initial form for the next removal operation after rinsing with water. The adsorbent retained functionality despite several cycles during sorption-elution-regeneration operations. [ABSTRACT FROM AUTHOR]