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Genomic selection (GS), which uses estimated genetic potential based on genome-wide genotype data for a breeding selection, is now widely accepted as an efficient method to improve genetically complex traits. We assessed the potential of GS for increasing soluble solids content and total fruit weight of tomato. A collection of big-fruited F1varieties was used to construct the GS models, and the progeny from crosses was used to validate the models. The present study includes two experiments: a prediction of a parental combination that generates superior progeny and the prediction of progeny phenotypes. The GS models successfully predicted a better parent even if the phenotypic value did not vary substantially between candidates. The GS models also predicted phenotypes of progeny, although their efficiency varied depending on the parental cross combinations and the selected traits. Although further analyses are required to apply GS in an actual breeding situation, our results indicated that GS is a promising strategy for future tomato breeding design.

The design and construction of an undrained ring shear apparatus, which was newly developed at Disaster Prevention Research Institute, Kyoto University, are presented in detail. This apparatus is suited for undrained shear tests under all types of loading, and enables observing the undrained shear behavior of soils in high-speed motion (maximum rotating speed 2.24 m/s) to an endless displacement level. Using rubber edges and a gap control system, leakage of pore water was effectively prevented, and the friction of rubber edges was controlled with high credibility during shearing. For undrained shearing tests on sand, the related experimental procedures are introduced and the undrained shear behavior of sand in ring shear test is presented. Test results showed that high pore water pressures could be built up in both loose and dense sands, given the shear displacement is great enough.

During pregnancy, the uterus shows marked morphological and physiological changes under the regulation of ovarian steroid. To elucidate the molecular cues of these changes, we tried to identify the transcripts differentially expressed in the pregnant rat uterus by using the suppression subtractive hybridization method. Seven independent clones were isolated and one of the up-regulated genes was secreted frizzled-related protein 4 (sFRP4). sFRP4 contains a Wnt-binding domain and belongs to the secreted frizzled protein family whose members are assumed to function as modulators of the Wnt signal. The expression level of sFRP4 mRNA reached a peak in the pregnant uterus on day 12, when uterine decidualization was almost complete in the rat. In situ hybridization histochemistry revealed that sFRP4 transcripts were observed in the decidual cells. In addition, proliferating cell nuclear antigen (PCNA)-positive cells were shown to be overlapped in decidua, suggesting that sFRP4 mRNA expression was accompanied by the late phase of decidual cell proliferation. Moreover, sFRP4 and estrogen receptor-alpha transcripts were co-localized. Furthermore, we analyzed the regulation of sFRP4 by estrogen using 17 beta-estradiol-treated ovariectomized rats. sFRP4 mRNA was detected in the uterus at 48 h after estrogen treatment, especially in endometrial stroma where PCNA-positive cells were also observed. The results in this study led us to the notion that sFRP4 mRNA may be up-regulated after estrogen treatment in the late phase of uterine cell proliferation.

Abstract: Background. A prospective randomized study was designed to determine whether flutamide (FLU) administered before treatment with a luteinizing hormone-releasing hormone agonist (LH-RHa) prevented prostate-specific antigen (PSA) flare in prostate cancer patients. Methods. Prostate cancer patients were randomized into two groups and received either FLU (n = 11) or no pretreatment (n = 13) for 2 weeks before the initial injection of LH-RHa. LH-RHa (every 4 weeks) and FLU (every day) were administered throughout the period of this study. Blood samples, for the determination of PSA, testosterone (T), and luteinizing hormone levels, were collected before FLU administration, and before and 2, 7, 14, 28, 56, and 84 days after the first administration of LH-RHa. Results. Treatment with FLU prior to LH-RHa induced an early decline in PSA level. The mean PSA level showed no significant secondary rise after LH-RHa administration in those patients with FLU pretreatment. Patients in both groups showed T flare after the first LH-RHa administration. However, the number of patients with PSA flare was significantly lower in patients with prior FLU administration than in those with LH-RHa alone. Conclusion. These results clearly demonstrate that, in patients with prostatic cancer, the administration of FLU for 2 weeks prior to the first LH-RHa administration is effective in preventing PSA flare, as well as in inducing an early decline in PSA levels.

Abstract: The NCR promoter (PNCR) from soybean chlorotic mottle virus (SoyCMV) was used to express the selectable marker, neomycin phosphotransferase (nptII) gene, in Agrobacterium-mediated transformation of both monocot (rice) and dicot (tobacco) plants. A multi-cloning site for insertion of a gene of interest into the binary vector pTN is located proximal to the right border region of T-DNA. When chimeric genes under the control of other strong promoters were located in a head-to-head orientation to the PNCR-nptII gene, kanamycin-resistant tobacco shoots were generated more efficiently than when using the original pTN vectors. This suggests that the enhancer-like sequences in the promoters adjacent to PNCR may promote expression of the PNCR-nptII gene.

The pre-existence of alpha2-->8-linked disialic acid (di-Sia) and oligosialic acid (oligo-Sia) structures with up to 7 Sia residues was shown to occur on a large number of brain glycoproteins, including neural cell adhesion molecules (N-CAMs), by two highly sensitive chemical methods (Sato, C., Inoue, S., Matsuda, T., and Kitajima, K. (1998) Anal. Biochem. 261, 191-197; Sato, C., Inoue, S., Matsuda, T., and Kitajima, K. (1999) Anal. Biochem. 266, 102-109). This unexpected finding was also confirmed using a newly developed antibody prepared using a copolymer of alpha2-->8-linked N-acetylneuraminyl p-vinylbenzylamide and acrylamide as an immunogen and known antibodies whose immunospecificities were determined to be di- and oligo-Sia residues with defined chain lengths. The major significance of the new finding that di- and oligo-Sia chains exist on a large number of brain glycoproteins is 2-fold. First, it reveals a surprising diversity in the number and M(r) of proteins distinct from N-CAM that are covalently modified by these short sialyl glycotopes. Second, it suggests that synthesis of di- and/or oligo-Sia units may be catalyzed by alpha2-->8-sialyltransferase(s) that are distinct from the known polysialyltransferases, STX and PST, which are partially responsible for polysialylation of N-CAM.

Abstract: The nitrite ion content and activity of nitrate reductase and nitrite reductase were examined in scutellum-derived calluses of rice varieties using a modified R2 medium (medium A) and a medium derived from the modified R2 medium (medium B). In medium A, marked differences were observed in callus growth between the varieties. The calluses of the poor-growth varieties accumulated significantly more nitrite ions during the culture period than did the good-growth varieties. Callus growth rate was negatively correlated with the nitrite ion content, indicating that the calluses of the poor-growth varieties were injured by toxic nitrite ions, which lead to browning and inhibited growth. The calluses of the poor-growth varieties had significantly lower levels of nitrite reductase activity than good-growth varieties. On the other hand, no between-group differences were observed in the nitrate reductase activity. These results indicate that the higher nitrite ion levels observed in the poor-growth varieties resulted from a lower ability to reduce nitrite and that nitrite reductase activity is one of the physiological factors that correlates with differences between varieties in rice cell cultures. In medium B, the calluses of the poor-growth varieties grew as well as the good-growth varieties, but also had significantly lower levels of nitrite reductase. Nitrate reductase activity was repressed in the calluses of both varieties in medium B compared to culture in medium A. The results suggest that repressed nitrate reductase activity causes the calluses of poor-growth varieties to accumulate only trace amounts of nitrite ions despite lower nitrite reductase activity and as a result, callus growth improved in medium B.

cDNA clones for two isogenes of nitrate reductase (NR) have been isolated from rapeseed (Brassica napus L.) androgenetic haploid embryos induced by microspore culture. NR mRNA accumulation can be detected by northern hybridization at 14 d after culture initiation when embryos develop to the heart/torpedo-shaped stage. Whole-mount in situ hybridization experiments demonstrate that the mRNA accumulation is developmental stage specific. In addition, even when cultured in media containing no nitrate, embryos accumulated NR mRNA to almost the same level as the control. This indicates the unique regulation of NR in embryogenesis in which NR mRNA transcription is activated in a developmental stage-specific manner that is independent of nitrate induction. In zygotic embryogenesis, a stage-specific accumulation of NR mRNA was also observed. By contrast, the obvious effect of nitrate on NR expression that has been reported in many plant species was also confirmed in rapeseed leaf. Quantitative combined reverse transcription-polymerase chain reaction analysis suggests that the flexible and variable regulation of NR expression, which is organ specific, nitrogen metabolite specific, and developmental stage specific, is caused principally by regulation of one major structural gene.

Abstract: A procedure for direct gene transfer into isolated microspores of rapeseed (Brassica napus L.) and the production of fertile transgenic plants is presented. By modifying the microspore culture method and adopting the firefly luciferase (Luc) gene as a non-destructive marker, we could obtain stably transformed androgenetic embryos from bombarded microspores. Luc-positive embryos were easily isolated from the large non-transformed population using a high-sensitivity bioluminescent image analyzer. PCR and Southern blot analyses confirmed that the introduced transgene was integrated stably into the genome of the selected embryos. Diploidized plants obtained from the haploid embryos were self-pollinated, and all of the offspring tested were Luc-positive, indicating rapid fixation of the transgene which is characteristic of doubled haploids.

The propagation of the Rayleigh surface wave is experimentally studied along the top surface of used railroad rail under conditions where ultrasonic pulses have carrier frequencies ranging from 0.4 to 3.0 MHz and approximately 10 µs duration. The generation of the first higher (M21 or Sezawa) mode as well as the fundamental (M11) mode and their dispersion properties are observed. These phenomena are attributable to the presence of the cold-worked surface layer caused by the wheel passage. It is shown that a theoretical model of a single layer overlying a half space, whose elastic constants are determined by a destructive method, yields results which agree with the dispersion curves obtained experimentally. On the basis of this one-layered model, an inversion method to estimate the layer thickness and its elastic constants is discussed.

In this paper, experiments show Love wave generation along the top surface of used railroad rail, where the shear wave velocity has been slightly reduced by the cold-working of wheel passage for years. The rf pulses used in the experiments have about 10 µs duration and a relatively narrow frequency spectrum. The group velocity of the Love wave is found to have a strong dependence on the carrier frequency over the tested range of 0.45–3.1 MHz. Application of the seismological one-layered model to the experimental measurements yields an NDE technique for the elastic properties and the thickness of the cold-worked surface layer. The results are interpreted on the basis of a destructive observation by micro-Vickers hardness testing.

This paper explores the feasibility of the acoustoelastic birefringence method for monitoring the axial stresses in the railroad rails. An electromagnetic-acoustic transducer (EMAT) is incorporated with a superheterodyne-phase-sensitive detector to accomplish noncontacting stress measurements. Two different measurement techniques are employed and compared to each other, both of which use the polarized shear waves propagating transversely to the rail axis. One is the pulsed resonance spectroscopy technique applied to the web, where the surfaces are nearly parallel to each other and support the thickness oscillations. The other method detects the small phase shift that occurs along with the stress application. The phase shifts were measured for the discrete reflection echoes that traveled long distances (top-to-bottom echo and multiple echoes in the head of the rail). The compressive axial load was raised up to 60 tons with the Shinkansen (bullet train) rail samples, which exceeds the buckling load of long rails. Both techniques showed a linear response to stress with a sufficient sensitivity and robustness, which promise the development of a practical railroad maintenance technology. The effects of the liftoff and the residual stress distribution are determined.

A nondestructive Lankford value (r-value) evaluation system applicable to a production line was developed. The system measures ultrasonic velocity changes induced by texture with S0 Lamb wave Electromagnetic Acoustic Transducers (EMATs)The system is composed of EMATs, driving circuits, receiving circuits and the frame bridge. Three pairs of EMATs were placed at three different angles (0°, 45°, 90°) to the sheet rolling direction. The propagation time measured by the EMATs was analyzed and the averaged r-value was evaluated continuouslyBasic experiments with permanent-magnet and electromagnet type EMATs for S0 mode Lamb wave were made to investigate characteristics such as sensitivity, gap effect, magnetic effect, production line speed effect, etc. Finally, the electromagnet-type EMATs making use of the magnetostrictive effect were adopted, since they had a high sensitivity at 5mm air gap from a steel sheet in the production line. By using the system with this type of EMATs, we confirmed that the averaged r-value was estimated in the accuracy of σ = 0.07 in various kinds of low carbon steel sheets.

The dependence of acoustoelastic constants on external magnetic fields is experimentally investigated for JIS-SS41 mild steel specimens. In the case of ferromagnetic materials, the elastic wave velocities at a demagnetized state are slightly smaller than those at a highly magnetized state. This occurs due to the magnetoelastic interaction, which in turn depends on the stress state. In the present study, we measured the propagation velocities of longitudinal and shear waves in steel specimens as functions of uniaxial stress and external magnetic field. We found that in the demagnetized state, the velocity change with stress showed different slopes for compressive and tensile loading. The difference decreased as the specimens were magnetized, approaching its saturation. As for acoustoelastic birefringence, which measures the principal stress difference, the effect of magnetoelastic interactions is relatively weak, while for the longitudinal/shear wave velocity ratio, which is proportional to the sum of principal stresses, this effect may induce considerable errors. Magnetization of steel components is then recommended to improve the accuracy of acoustoelastic stress measurements. A discussion is given for the strength of magnetization required.

Two recombinant phage clones bearing sequences corresponding to the beta subunit of human chorionic gonadotropin (hCG beta) were isolated from a human genomic library. The beta sequences were mapped by blot hybridization of restriction digests of these phage DNAs and the nonoverlapping inserts were subcloned in pBR322 and sequenced. The nucleotide-sequencing data show that the hCG beta subunit is encoded by at least three nonallelic genes. Moreover, based on restriction analyses of human placental DNA, these genes may be linked in a single cluster with four other hCG beta-like genes. The sequenced genes all differ in their 5' flanking regions, and none of them is completely homologous in sequence to either of two hCG beta cDNA clones used here. In the translated region of one of these genes, three base substitutions result in two changes from the reported amino acid sequence. In the family of beta-containing glycoprotein hormones, the hCG beta subunit is unique in that it contains an extension of 29 amino acids at its COOH end. The DNA sequence corresponding to this region in the sequenced genes is part of a larger exon. These data show that the COOH-terminal extension does not result from splicing of the primary RNA transcript.

Abstract: X-ray stress analysis is a standard nondestructive stress-measurement technique, but its use is limited in the sense that only a surface layer is surveyed. Recently, acoustoelasticity has emerged as a technique for nondestructive stress analysis. Acoustoelasticity makes use of stress-induced acoustic-birefringent effects. It gives stress distributions averaged through the thickness of a specimen. This technique is attractive because it does not require a transparent plastic model as photoelasticity does. However, much should be done before this method is established as a standard nondestructive technique of stress analysis. The most important among them is to separate stress-induced birefringence from that introduced by texture structure. For special cases, such as axisymmetric stress distributions and when a stress-free region is knowna priori, residual-stress distributions can be evaluated nondestructively. In this paper, we measured residual-stress distribution in a wide-flanged rolled beam by using a recently developed T-type transducer. The results were compared to those obtained from conventional destructive methods.

An ultrasonic on-line system to measurer values in cold rolled steel sheets has been developed with electromagnetic acoustic transducers (EMATs). These EMATs are composed of meanderline coils and electromagnets and operate with the magnetostrictive mechanism. The EMAT instrument measures the propagation times of the fundamental symmetrical Lamb (So) wave at a low frequency and relates them to ther values through a calibrated regression curve. Preliminary tests indicate that the on-line monitoring ofr is quite feasible with a standard deviation of 0.07 for various low carbon steel sheets; the thicknesses range from 0.5 mm to 2.5 mm. The measuring time is 20 msec per data. The liftoff is allowed to 5 mm with 2 mm thick sheet. Ther evaluation is independent of the line speed up to 325 m/min. These promising results promote installation of ultrasonicr-value measurement systems in steel production lines.

When white clover plants were self-pollinated, 75% of a 143-plant population did not set seed. Plants which did set small numbers of seed probably did so as a result of pseudo-self-compatibility. One highly self-compatible plant was selected from the breeding materials. The S2 progeny of this plant was autogamous and genetically fixed for morphology and isozyme patterns. Genetic analyses of self-compatibility were conducted as far as the F3 progeny. It was concluded from these data that self-compatibility was inherited in a simple Mendelian way and that plants homozygous for self-compatibility were obtained. There was no correlation between presence or absence of self-compatibility and growth vigor. The possibility of application of self-compatible plants to recurrent selection procedures is outlined and the utilization of self-compatible plants in white clover breeding programs is discussed.

We studied the ultrasonic velocity change caused by the accumulative creep damage in polycrystalline pure copper after high-temperature tensile loading. The propagation velocities of bulk waves, longitudinal and shear waves polarized parallel and perpendicular to the stress direction, showed a strong sensitivity to intergranular creep controlled by grain-boundary cavitation and subsequent microcracking. The velocities decreased slowly with creep time up to approximately 60 pct of the lifetime, when the steady creep shifted to the tertiary creep. Beyond this point, they decreased at ever increasing rates until eventual failure. The total velocity changes amounted to several percent of the original velocities. The creep damage also caused velocity anisotropy in the shear waves. Evolution in the anisotropy revealed that formation of cavity arrays, cavity coalescence, and microcracking, which occurred preferentially on boundaries lying normal to the stress axis, were restricted to the last 20 pct of the lifetime. Metallography and measurements of porosity support the ultrasonic observations.

The acoustoelastic effect is investigated for the Rayleigh surface wave propagating in a homogeneous isotropic material. The initial deformations considered are uniform and nonuniform only in the direction of depth. The formulas for the velocity change versus the change in the applied static stress are derived in the first-order approximation. The result for the uniform case, reducing to that of Hayes and Rivlin, exhibits no dispersion and the velocity change proportional to the principal strains. To be noted is the result that the Rayleigh wave becomes dispersive under the nonuniform stress state, depending roughly on the product of the wave number and the characteristic depth over which the stress varies. The dispersion is remarkable for the relatively low frequency and diminishes as the frequency increases. The analytical results are verified by measurements with mild-steel samples on the basis of the sing-around technique.

Residual stress in the rim of railroad solid wheel was measured nondestructively by an acoustoelasticity method which makes use of the birefringent effect. The acoustic anisotropy is a fractional velocity difference of two shear waves polarized perpendicularly in principal directions and is proportional to the principle stress difference. However, in order to get the residual stress nondestructively, the contribution of texture anisotropy has to be separated from the total acoustic anisotropy. The scatter of the texture anisotropy was investigated using seven wrought wheels, four of which were used for drag brake tests that were to change the residual stress level. The initial and after braked residual stress was analyzed by acoustoelasticity, and the results were compared with the conventional methods and FEM analysis. Conclusively, it is expected through this study that the residual stress averaged through thickness in the rim can be assessed nondestructively by using the average value of the texture anisotropy in the rim within 40 MPa of difference compared with the estimation by conventional destructive methods.

The theory of elastic waves superposed on finite deformation is applied to the study of thickness oscillations in a deformed elastic plate. Perturbation scheme, based on multiple scales, is employed to obtain a set of governing equations for the amplitudes of transverse thickness oscillations which are perpendicularly polarized with each other. It is shown that such oscillations, being strongly coupled by the initial deformation, undergo slow and sinusoidal amplitude modulation and slight shift in the resonance frequencies. The results suggest new techniques of experimental stress analysis.

Small fatigue crack growth in 7075-T651 aluminum is periodically monitored with an ultrasonic Rayleigh wave technique. The wideband reflection signals are digitized and stored in the computer memory to permit the signal processing in the frequency domain. With the help of the constructed three-dimensional (3-D) reflection coefficient, the reflection amplitude spectra yield the measurements of the crack depth, if larger than 0.062 mm, and the crack closure stress. Acoustically obtainedda/dN-ΔKeffrelations describe the anomalous growth behavior of small surface crack, extending from the late small crack regime to the large crack regime passing through the minimum growth rate. The split spectrum processing proves to be useful in removing the grain noises to illuminate the target echoes, which is necessary to detect the nucleation and characterize the cracks smaller than 0.1 mm in depth. Discussions on the computer-controlled, automated,in situmonitoring system are provided.

Abstract: An ultrasonic technique for evaluating the formability of cold-rolled steel sheets is developed. The technique is based on the generalized dispersion relation, which correlates the velocity anisotropy of ultrasonic plate modes guided in the sheet plane to the texture defined by orientation distribution coefficients. Electromagnetic acoustic transducers (EMAT’s), constructed of permanent magnets and meander-line coils, allow the accurate and easy measurement of transit times of theS o (fundamental symmetric) mode. The planar average of the transit times shows a close correlation with both the planar average of plastic strain ratios (r value), obtained through tensile tests and the pole intensities, measured with the X-ray diffraction method. These favorable comparisons with the destructive tests indicate a good possibility of texture monitoring with the noncontacting EMAT’s.

Abstract: The acoustoelastic stress analysis is based on the fact that an initially isotropic material becomes anisotropic under stress. The birefringent effect for polarized ultrasonic shear waves in the stressed material will then be similar to the photoelastic effect in which a light wave and a transparent model specimen are used. In this paper, the velocity differences of acoustical, perpendicularly polarized waves are measured directly by a lsquosing-aroundrsquo method using a 5-MHz shear-type transducer. The residual-stress distribution in a mild-steel circular plate with a concentrically patch-welded joint is measured by this method. The acoustoelastic coefficient is obtained separately by uniaxial testing of the base material. The results show that the acoustical stress measurement, carried out nondestructively, agrees well with those obtained by conventional destructive methods as well as with theoretical predictions.

Extrusion is one of the most widely used processes for polymer processing, e.g., producing film, pipe, sheet, cable and pellet. The shape of extrusion die has an important part for the manufacturing products. The purpose of this study has been to confirm the influence of nozzle shape on polymer flow. We calculated the die flow simulations in the various parameters. The calculation results are expected to improve the efficiency of pelletization. A commercial computer fluid dynamics program Ansys Fluent was used to calculate the die passage. The parameters for the calculations were taper angle, outlet diameter, properties of polymer and two models. The governing equations were the incompressible momentum equation and the continuity equation. As results, the increase in flow rate was confirmed by increasing taper angle and outlet diameter in the specific dimensional range. The average outlet velocity of single and multi-nozzle models almost corresponded in each same parameter.

The unsteady supersonic jet formed by a shock tube with a small high-pressure chamber was used as a simple alternative model for pulsed laser ablation. Understanding the vortex ring formed by the shock wave is crucial in clarifying behavior of unsteady supersonic jet discharged from elliptical cell. The purpose of this study has been to reveal behavior of the supersonic jet and the vortex rings. The unsteady behavior of a flow is investigated numerically by solving the axisymmetric two-dimensional compressible Navier-Stokes equations. The system of the calculation is a model of laser ablation of a certain duration followed by discharge through the cell exit. The parameters for the calculations are the pressure ratio of the shock tube and the cell diameter. As a result, it was found that the diameter of the elliptical cell had the effect on the interaction between vortex rings and the jet.

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