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The motions of relativistic particles in a magnetosonic shock wave propa- gating obliquely to an external magnetic field are studied. In the zeroth-order theory, particles continue to move nearly parallel to the external magnetic field in the shock transition region, when the shock speed is close to $c \cos \theta$, where $c$ is the speed of light and $\theta$ is the propagation angle. Perturbations to this zeroth-order motion are also analyzed for positrons and ions. The perturbation frequency of positrons is $\omega \sim \Omega_{\rm p0} \gamma^{-1}$ and that of ions is $\omega \sim \Omega_{\rm i0} \gamma^{-1/2}$, where $\Omega_{\rm p0}$ and $\Omega_{\rm i0}$ are the non-relativistic gyrofrequencies of positrons and of ions, respectively, and $\gamma$ is the Lorentz factor. These theoretical predictions are confirmed with numerical simulations.

Objective. We previously described abnormalities in the bone marrow of patients with rheumatoid arthritis (RA), but were able to shed little light on the pathogenic roles of inflammatory cytokines and proteinases in joint destruction in the subchondral region in RA. This is the first report to describe the co-localization of cytokines and proteinases in this area.
Methods. Decalcified paraffin-embedded sections from 10 patients with RA and five patients with osteoarthritis (OA) were examined for the immunolocalization of cathepsins B, K and L and the localization of messenger RNAs for interleukin 1β (IL-1β), tumour necrosis factor α (TNF-α) and matrix metalloproteinase 9 (MMP-9). The cells were double-stained with anti-CD68 or anti-prolyl 4-hydroxylase (PH) antibody.
Results. An immunohistochemical study confirmed the expression of cathepsins B and L by CD68-positive mononuclear cells at the sites of significant cartilage and bone erosion from the subchondral region in all RA specimens. Osteoclast-like cells showed intense staining for cathepsin K and MMP-9. Osteoblast-like cells strongly expressed MMP-9. Analysis of serial sections revealed that expression of the IL-1β and TNF-α genes occurred near that of the cathepsins and MMP-9 in the subchondral region.
Conclusion. We conclude that inflammatory cytokines and tissue-damaging proteinases play important roles in joint destruction in the subchondral region in RA.

CAD (caspase-activated DNase) can cause DNA fragmentation in apoptotic cells. Transgenic mice that ubiquitously express a caspase-resistant form of the CAD inhibitor (ICAD) were generated. Thymocytes prepared from the mice were resistant to DNA fragmentation induced by a variety of stimuli. However, similar numbers of TUNEL-positive cells were present in adult tissues of transgenic and wild-type mice. Exposure to gamma-irradiation caused a striking increase in the number of TUNEL-positive cells in the thymus of wild-type, but not transgenic, mice. TUNEL-positive nuclei in transgenic mice were confined to thymic macrophages. When apoptotic thymocytes from the transgenic mice were cocultured with macrophages, the thymocytes underwent phagocytosis and their chromosomal DNA underwent fragmentation. This DNA fragmentation was sensitive to inhibitors that block the acidification of lysosomes. Hence, we conclude that the DNA fragmentation that occurs during apoptosis not only can result cell-autonomously from CAD activity but can also be attributed to a lysosomal acid DNase(s), most likely DNase II, after the apoptotic cells are engulfed.

Nondestructive measurements of residual stresses were successfully attempted by the acoustoelastic technique on butt-welded joints of a carbon steel for nuclear piping. Usefulness of the technique considering the effect of the material anisotropy is emphasized. Based on the measured residual stresses, predictions of the fatigue crack growth were done using the superposition technique. It is shown that predictions agree well with experiments. The effect of the accuracy in residual stress measurements on the predictions is also included.

Diamond films were provided by a hot filament thermal chemical vapour deposition method with an H2-CH4 gas mixture under various reaction conditions: CH4/H2 ratios of 0.5% and 1.0%, Si and Cu substrates, a substrate temperature of 750 °tC, a pressure of 7 torr and a reaction time of 12 h. TEM observation showed that the films produced have many defects such as twins, stacking faults and large distortion of lattices. These defects, which increase with increasing CH4 concentration, seem to be introduced during the crystal growth process. Fivefold symmetry twinned crystals were often observed in the diamond films.

We attempted to determine wheter all cases of AWTA (anirida-Wilms tumor association) or any of the following groups of patients show 11p deletion: cases of Wilms tumor with congenital abnormalities other than aniridia, those without any congenital abnormalities, tumor itself in cases of Wilsm tumor without constitutional 11p deletion and cases of aniridia or hemihypertrophy without Wilms tumor. We studied a total of 29 index patients including five cases of AWTA, four cases of Wilms tumor with various congenital abnormalities, 16 cases of Wilms tumor without other abnormalities, three cases of aniridia in one of which Wilms tumor developed later and a case of hemihypertrophy.

A theoretical model for3He enrichments in solar energetic particles is developed. First, current-driven, electrostatic instabilities that have frequencies $$\omega \approx n\Omega 3_{{\rm H}e} $$ ( $$\Omega 3_{{\rm H}e} $$ is the cyclotron frequency of3He) are investigated for a plasma consisting of H,4He,3He, and electrons with the density of3He much lower than those of H and4He. It is found that in many cases the oblique ion-acoustic waves can have positive growth rates at frequencies $$\omega \approx \Omega 3_{{\rm H}e} $$ and, at the same time, negative growth rates at $$\omega \approx \Omega 4_{{\rm H}e} $$ and at? ˜ OH. This can occur near the marginal state of the instability. The wave damping at these frequencies is caused by the cyclotron resonances of4He and H. The cyclotron damping at $$\omega \approx \Omega 3_{{\rm H}e} $$ is negligible, however, because the abundance of3He is very small. The H cyclotron waves can be unstable at $$\omega \approx 2\Omega 3_{{\rm H}e} $$ for a wide region of plasma parameters; the electron-to-ion temperature ratio must beTe/TH ? 1.5. To destabilize the4He cyclotron waves with $$\omega \approx \Omega 3_{{\rm H}e} $$ , high4He density and high electron temperature are both required. Then,3He enrichments are studied on the basis of the theory of nonlinear magnetosonic waves, which can promptly accelerate ions. The current-driven electrostatic waves with $$\omega \approx n\Omega 3_{{\rm H}e} $$ can enhance fluctuation velocities of3He. Thus, in the presence of these waves, magnetosonic waves can selectively accelerate3He particles to high energies. Finally, cyclotron resonances of heavy ions with the waves $$\omega \approx n\Omega 3_{{\rm H}e} $$ or $$\omega< \Omega 4_{{\rm H}e} $$ are briefly discussed.

Nondestructive measurements of residual stresses were successfully attempted by the acoustoelastic technique on butt-welded joints of a carbon steel for nuclear piping. Usefulness of the technique considering the effect of the material anisotropy is emphasized. Based on the measured residual stresses, predictions of the fatigue crack growth were done using the superposition technique. It is shown that predictions agree well with experiments. The effect of the accuracy in residual stress measurements on the predictions is also included.

To understand the bone resorption and lysosomal proteinases in osteoclasts, we examined by immunohistochemistry the localization of lysosomal cysteine and aspartic proteinases, acid phosphatase, and cystatin-beta in the rat tibial bone. Immunoreactivity for cathepsins B, C, H, and L, cathepsin D, acid phosphatase, and cystatin-beta was demonstrated in various cells of the bone tissue; in particular, large multinucleated osteoclasts attached to the bone surface and chondroclasts in the proximal growth plate. These cells showed intense immunoreactivity for these lysosomal enzymes and cystatin-beta. Bone surface-lining osteoblasts displayed distinct immunoreactivity for cathepsins B, C, D, H, and acid phosphatase, while osteocytes often exhibited that for cathepsins D, H and acid phosphatase. Chondrocytes in the growth plate demonstrated intense immunoreactivity for cathepsins B, D, and acid phosphatase. Immunoreactivity for cystatin-beta was detected in osteoclasts and chondroclasts only. Large, round multinucleated cells free from the bone surface exhibited weak, faint, or no immunoreactivity for the lysosomal enzymes and cystatin-beta. These results suggest that lysosomal cysteine and aspartic proteinases may play a role in the degradation of organic constituents of the bone matrix. Moreover, cystatin-beta can serve as an excellent marker protein for osteoclasts.

A model of 3He enrichments, which was proposed recently, is extended to study enhancements of heavy ions in high-energy particles. With weak currents parallel to the ambient magnetic field, oblique ion-acoustic waves and H cyclotron waves can become unstable. The former can have much greater growth rates at frequencies ? ˜ O3He than at ? ˜ O4He near the marginal states of instabilities. The latter can be unstable at ? ˜ O3He for a wide region of plasma parameters. Thus they could cause 3He enrichments through cyclotron resonances. At the same time, these waves can resonate with first or higher harmonics of cyclotron frequencies of many other ions. We investigate these resonant ions for several cases of plasma temperature. This model predicts enhancements of heavy elements and of neutron-rich isotopes at T ˜ 10 MK. It shows heavy ion enhancements also at T ˜ 4 MK. Clear differences between these two temperatures, however, can be seen in charge states of ions. At T ˜ 2 MK, light ions as well as heavy ions can have cyclotron resonances with these waves, which suggests that such low temperatures are excluded.

In this paper, a method is proposed for improving the accuracy of the stability criterion by enlarging the estimation of the stability region determined by means of Lyapunov's direct method using series expansion, and by putting it closer to the actual stability region. The Lyapunov function obtained by energy integration is used as the first estimation. The method is applied to a single-machine infinite bus power system, and the stability domain in the δ-ω plane is shown together with the actual stability domain obtained by numerical integration. It is shown that the application of the proposed method results in a considerable improvement in the stability boundary estimation over that given by the original Lyapunov function. Zubov's method, which obtains an accurate stability boundary using the series expansion, is related to the method proposed in this paper. The last section is, therefore, devoted to comparing the two methods and examining the possibility of their application to multi-machine power systems.

This report presents a familial amyotrophic lateral sclerosis (FALS) patient with widespread vacuoles and hyaline inclusions strongly immunostained with the anti-superoxide dismutase (SOD1) antibody. The overall pathologic similarity between our non-SOD1-linked FALS patient and transgenic mice expressing a mutated human SOD1gene suggests that common pathogenetic mechanisms other than an SOD1mutation exist in the development of these disease.

A rare case of infradiaphragmatic pulmonary sequestration with an antenatally diagnosed abdominal tumor is reported. Extirpation of the tumor was performed 2 months after delivery; the histological examination showed alveolar and bronchial tissue.