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We investigated the atomic fill site probability distributions across supercell structures of RT12-xTi (R=Nd, Sm, T=Fe, Co). We use a combined molecular dynamics and Boltzmann distribution approach to extrapolate the probability distributions for Ti substitution from lower to higher temperatures with an equilibrium condition to assess how temperature affects the predictability of the structures fill path. It was found that the Nd and Sm based Fe systems have the highest filling probability path at lower temperatures but the cohesive energy change due to Ti substitution in Sm and Nd based crystals indicates that a more stable system could be achieved with a combination Co and Fe in the transition metal site., Comment: 5 pages, 4 figures, 2 tables

We describe the process of multiscale modelling of magnetic materials, based on atomistic models coupled parametrically to micromagnetic calculations. At the atomistic lengthscale we use Spin Dynamics (SD) to study switching mechanisms, using structures predicted by Molecular Dynamics. The process is completed using SD to calculate the cell size and temperature dependent parameters for micromagnetic calculations. We demonstrate an unusually weak cell size scaling for Nd2Fe14B and demonstrate numerically the existence of atomic scale Barkhausen jumps during magnetization switching. Scaling of magnetic properties is shown to be important in micromagnetic calculations of hysteresis, especially considering variation in micromagnetic cell size.

We describe the process of multiscale modelling of magnetic materials, based on atomistic models coupled parametrically to micromagnetic calculations. At the atomistic lengthscale we use Spin Dynamics (SD) to study switching mechanisms, using structures predicted by Molecular Dynamics. The process is completed using SD to calculate the cell size and temperature dependent parameters for micromagnetic calculations. We demonstrate an unusually strong cell size scaling for Nd2Fe14B, and demonstrate numerically the existence of atomic scale Barkhausen jumps during magnetization switching. Scaling of magnetic properties is shown to be important in micromagnetic calculations of hysteresis, especially considering variation in micromagnetic cell size.

Ten alloys and nitrogenated compounds of (R,Zr)(Fe,Co) 11.0–11.5 Ti 1.0–0.5 N y (y=1.0–1.4 for R=Nd, y=0 for R=Sm) with a ThMn 12 -type structure were prepared. The average Fe–Fe interatomic distances, d(Fe–Fe), for Fe sites were calculated based on the reported atomic parameters. The hyperfine splittings (inner field (IF), in teslas) were measured by Mossbauer spectroscopy, and the IF increased with increasing d(Fe–Fe) for Fe sites, indicating a magneto-volume effect. The order of IF magnitude in Fe sites was Fe(8i)>Fe(8j)>Fe(8f) in all alloys. Co substitution for Fe sites, (Fe 0.75 Co 0.25 ), increased the IF by 25% for the R=Nd alloy and 15% for the R=Sm alloy. Decreasing Ti content from −Ti 1.0 to −Ti 0.5 , which increased the Fe and Co content, preserved the ThMn 12 structure with Zr substitution for R(2 a ) sites, and caused a slight increase in the IF of 2% for the R=Nd alloy and 7% for the R=Sm alloy. Nitrogenation, where N was introduced into the 2b sites, also increased IF in R=Nd alloys, by 23% for the Co- and Zr-free alloys, NdFe 11 Ti 1.0 N 1.5 , and by 7% for the Co-containing, (Nd 0.7 Zr 0.3 ) (Fe 0.75 Co 0.25 ) 11.5 Ti 0.5 N 1.3 alloy. The IF values of the R=Nd alloys were slightly larger than those of the R=Sm alloys. In conclusion, the magneto-volume effect was clearly observed at the Fe sites, and Co substitution into Fe sites and nitrogenation (R=Nd alloys) compensated for the increased IF. Increasing the Fe and Co fractions also increased IF slightly.

(R,Zr)(Fe,Co) 12−x Ti x (R = Nd and Sm) alloys of ten different compositions were prepared by strip-casting. The elemental distribution of the sample particles after annealing was quite homogeneous. Existing phases in the prepared alloys were determined by X-ray diffraction and the occupation sites of the substituted elements (Ti, Co, and Zr) were determined using spherical aberration corrected scanning transmission electron microscopy. The ThMn 12 structure is stable in Ti 1.0 compounds for both R = Nd and Sm, but exhibited obvious precipitation of α-(Fe,Co) phases in low Ti content compounds with Ti 0.5 . Ti substitution into Fe(8 i ) sites is important for the stabilization of the ThMn 12 structure. Furthermore, the stability of low Ti content compounds could be recovered by the substitution of Zr into R(2 a ) sites. Co was mainly in Fe(8 j ) and Fe(8 f ) sites, which contributed to the stability of the 1–12 structure by increasing the configuration entropy. Analysis based on three Fe hexagons and two local sub-structural units suggested that the stabilization of ThMn 12 structure by Ti and Zr substitutions mainly originates by resolving local mismatches in interatomic distances in the structure.

We previously reported a new compound for permanent magnets, (Nd0.7Zr0.3)(Fe0.75Co0.25)11.5Ti0.5N0.56, which has a high saturation polarization (Js) of 1.68 T and a high magnetocrystalline anisotropy field (Ha) of 2.88–4.0 MA/m. Here, we examined the effects of substituting Co and Ti at the Fe sites and Zr at the Nd sites. Js increased with Co substitution at the Fe sites, and higher Fe and Co content could be achieved by decreasing the Ti content to −Ti0.5. The ThMn12 structure with high Fe and Co content (i.e. low Ti content) was stabilized mainly by −Zr0.3 substitution at the Nd sites. The Zr substitution resolves the local mismatch in atomic size in the structure. Specifically, the atomic radius of Zr is about 88% that of Nd, so the local structure surrounding Nd (2a site) shrinks as a result of the substitution and resolves the size mismatch in the three types of local Fe six-fold symmetric hexagons in the structure. The effect of the α-(Fe, Co) phase on Js was evaluated from the phase's volume fraction measurement of 7.7% (8.1 wt%) by electron backscatter diffraction. Nitrogenation of the starting alloy also resulted in augmentation of the c-axis magnetocrystalline anisotropy. Finally, we confirmed a high Js(−N1.3) of 1.71T (=1.67 T, −0.04 T for the α-(Fe, Co) phase) and Ha of 2.9–5.25 MA/m (Ha(−N1.3)=5.25 MA/m) in the (Nd0.7Zr0.3)(Fe0.75Co0.25)11.5Ti0.5Nα (α=0.60–1.30) compounds.

The maximum coercivity that can be achieved for a given hard magnetic alloy is estimated by computing the energy barrier for the nucleation of a reversed domain in an idealized microstructure without any structural defects and without any soft magnetic secondary phases. For Sm$_{1-z}$Zr$_z$(Fe$_{1-y}$Co$_y$)$_{12-x}$Ti$_x$ based alloys, which are considered an alternative to Nd$_2$Fe$_{14}$B magnets with lower rare-earth content, the coercive field of a small magnetic cube is reduced to 60 percent of the anisotropy field at room temperature and to 50 percent of the anisotropy field at elevated temperature (473K). This decrease of the coercive field is caused by misorientation, demagnetizing fields and thermal fluctuations., Comment: 5 pages, 4 figues

The low-temperature phase (LTP) MnBi is one of the few rare-earth free compounds that exhibit a large magnetocrystalline anisotropy energy in the order of 10 6 J/m 3 . A large coercive field ( μ 0 H cj ) above 1 T can be obtained readily by reducing the crystallite size ( D ) through mechanical grinding (MG). The room-temperature H cj values follow a phenomenological expression μ 0 H cj = μ 0 H a ( δ/D ) n where the anisotropy field ( μ 0 H a ) is ∼4 T, the Bloch wall width ( δ ) is 7 nm and the exponent ( n ) is about 0.7 in our study. The grain refinement upon MG is accompanied by suppression of the spin reorientation transition temperature ( T SR ) from 110 K to below 50 K. The coercive field starts to exhibit positive temperature dependence approximately 50 K above T SR and the room-temperature magnetic hardening induced by MG could partially be brought about by the lowered onset of this positive temperature dependence. The suppression of T SR by MG is likely to be induced by the surface anisotropy with which the 2nd order crystal field term is enhanced. One of the shortcomings of LTP-MnBi is its poor phase stability under the ambient atmosphere. The spontaneous magnetization decreases considerably after room-temperature aging for 1 week. This is due to oxidation of Mn which leads to decomposition of the MnBi phase. Hence, the surface passivity needs to be established before this material is considered for a permanent magnet in practical uses. Another shortcoming is the limited spontaneous magnetization. The theoretical upper limit of the maximum energy product in LTP-MnBi remains only a quarter of that in Nd 2 Fe 14 B. Nevertheless, owing to the unique positive temperature dependence of the first-order anisotropy constant ( K 1 ), the hardness parameter ( κ ) of LTP-MnBi is enhanced above room temperature; κ reaches as large as 2.8 at 580 K. This makes LTP-MnBi a possible candidate for the hard phase in rare-earth free nanocomposite magnets.

Magnetization reversal process in Nd-Fe-B nanocrystalline magnets was investigated by small-angle neutron scattering (SANS) using a non-polarized neutron beam. The magnetic-field dependence of the SANS intensities was obtained for as-deformed and Pr-Cu infiltrated Nd-Fe-B magnets. The SANS intensity variation with the magnetic field is suppressed in Pr-Cu infiltrated sample as compared with that in as-deformed sample. The isolation of Nd2Fe14B grains along the [001]-axis direction was found to be caused by the infiltration of the Pr-Cu eutectic alloy, resulting in coercive force enhancement. The results suggest that magnetic isolation of the grains is the key to developing magnets with high coercive force.

We report wet chemical synthesis of a hierarchical nanocomposite thermoelectric material, (Bi,Sb)2Te3 + 2 vol.% Sb2O3, which exhibits a very high ZT value of 1.5 at 333 K. The key to such a high ZT value is to design the interfacial density (ID) of the nanodispersion and the mean diameter of the matrix (d) in the nanocomposite. To this end, (Bi,Sb)2Te3 with Sb2O3 nanodispersion was developed using in situ precipitation during solvothermal treatment. Nanocomposite structure was observed in sintered specimens. By evaluation of thermoelectric properties, it was confirmed that phonon scattering on the surface of Sb2O3 dispersion and κph correspondingly decreased with ID. The formation of a well-controlled Sb2O3 dispersion (mean diameter of dispersion: D = 1.5 nm, ID = 0.06 nm−1) and fine grains (d = 38 nm) led to an extremely low lattice thermal conductivity of 0.28 W m−1 K−1, while reducing the electrical conductivity moderately according to the conventional mixture rule.

We have investigated the influence of multiple scattering on the magnetic small-angle neutron scattering (SANS) from a Nd–Fe–B nanocrystalline magnet. We performed sample-thickness- and neutron-wavelength-dependent SANS measurements, and observed the scattering vector dependence of the multiple magnetic scattering. It is revealed that significant multiple scattering exists in the magnetic scattering rather than the nuclear scattering of Nd–Fe–B nanocrystalline magnet. It is considered that the mean free path of the neutrons for magnetic scattering is rather short in Nd–Fe–B magnets. We analysed the SANS data by the phenomenological magnetic correlation model considering the magnetic microstructures and obtained the microstructural parameters.

Ce-based R2Fe14B (R= rare-earth) nano-structured permanent magnets consisting of (Ce,Nd)2Fe14B core-shell grains separated by a non-magnetic grain boundary phase, in which the relative amount of Nd to Ce is higher in the shell of the magnetic grain than in its core, were fabricated by Nd-Cu infiltration into (Ce,Nd)2Fe14B hot-deformed magnets. The coercivity values of infiltrated core-shell structured magnets are superior to those of as-hot-deformed magnets with the same overall Nd content. This is attributed to the higher value of magnetocrystalline anisotropy of the shell phase in the core-shell structured infiltrated magnets compared to the homogeneous R2Fe14B grains of the as-hot-deformed magnets, and to magnetic isolation of R2Fe14B grains by the infiltrated grain boundary phase. First order reversal curve (FORC) diagrams suggest that the higher anisotropy shell suppresses initial magnetization reversal at the edges and corners of the R2Fe14B grains.

Spin-polarized small-angle neutron scattering (Pol-SANS) measurements for nano-crystalline Nd-Fe-B magnet have been performed in order to clarify the magnetic reversal behavior. Due to high transparency of neutron beam, magnetic and nuclear microstructures in the `bulk' can be observed by SANS. Obtained SANS patterns arising from magnetic domain changes were analyzed by Teubner-Stray model, phenomenological correlation length model, to quantify the periodicity, density and morphology of magnetic domains. The results indicate that magnetic reversal evolves with magnetic domains which have the similar size of the grains. However, even in nano-crystalline system, single domain grain reversal is not realized.

Nanocomposite magnets (NCMs) consisting of hard and soft magnetic phases are expected to be instrumental in overcoming the current theoretical limit of magnet performance. In this study, structural analyses were performed on L1(0)-FePd/α-Fe NCMs with various hard/soft volume fractions, which were formed by annealing Pd/γ-Fe(2)O(3) heterostructured nanoparticles and pure Pd nanoparticles. The sample with a hard/soft volume ratio of 82/18 formed by annealing at 773 K had the largest maximum energy product (BH(max) = 10.3 MGOe). In such a sample, the interface between the hard and soft phases was coherent and the phase sizes were optimized, both of which effectively induced exchange coupling. This exchange coupling was directly observed by visualizing the magnetic interaction between the hard and soft phases using a first-order reversal curve diagram, which is a valuable tool to improve the magnetic properties of NCMs.

International audience; The coercive field and angular dependence of the coercive field of single-grain Nd$_{2}$Fe$_{14}$B permanent magnets are computed using finite element micromagnetics. It is shown that the thickness of surface defects plays a critical role in determining the reversal process. For small defect thicknesses reversal is heavily driven by nucleation, whereas with increasing defect thickness domain wall de-pinning becomes more important. This change results in an observable shift between two well-known behavioral models. A similar trend is observed in experimental measurements of bulk samples, where a Nd-Cu infiltration process has been used to enhance coercivity by modifying the grain boundaries. When account is taken of the imperfect grain alignment of real magnets, the single-grain computed results appears to closely match experimental behaviour.

In this study, we have investigated N2O oxidation of various off-angled 4H-SiC (0001) epilayers and characterized the properties of MOS interfaces. The oxide thickness almost linearly increases with increasing off-angle. Oxidation on highly off-angled (0001) 4H-SiC is faster than that on 8o off-axis (0001). The off-angle dependence of Dit is very small for the MOS capacitors in the off-angle range from 8o to 30o. The depth profiles of carbon and nitrogen atoms near the MOS interface on 15o off-axis 4H-SiC(0001) are similar to those on 8o off-axis (0001).

We have investigated the morphology and doping characteristics of 4H-SiC epilayers grown on 13o-22o off-axis (0001) substrates by horizontal hot-wall CVD. Step bunching is not observed on 18o off-axis substrates as well as on other substrates with large off-angles. The rms roughness is a minimum (as small as 0.10 nm) on 18o off-axis (0001). Under C-rich condition (C/Si >1.0), the donor concentration increases by increasing the off-angle, when the off-angle is larger than 15o. This trend in doping characteristic is enhanced in CVD growth at 1450-1500oC. At a high temperature of 1600oC, however, the off-angle dependence of donor concentration is significantly reduced. Epitaxial growth on 4H-SiC(000-1) with large off-angles is also reported.

オーバーデンチャーは, 歯冠/歯根比の改善や, 咬合平面の平坦化などの利点を有し, 主として少数残存歯症例に効果的に用いられている. しかし, 歯冠を切断し, 根面を義歯で被覆することによる問題点もみとめられる. また, 支台歯の延命効果が大きいことの反面, それをさまたげる修飾要素も多く, 残存歯の寿命を確実に予測することは困難である. 筆者がこれまで経験してきたオーバーデンチャーの症例を概観すると, 次の問題点に対しては, 解決策が得られたように思われる.(1) 根面板の脱落: 接着性レジンセメントの使用,(2) 義歯の破折: 適切な金属補強構造の設計,(3) 支台歯の清掃性の低下: 電動歯ブラシとPMTC. しかし, 残存歯の延命を第一の目的と考えた場合, 疑問と思われる設計のオーバーデンチャーが見受けられることもある. 少なくとも, 移行義歯としてのオーバーデンチャーと, 残存歯のできる限りの延命を意図したオーバーデンチャーとは, 明確に分けて考える必要があるだろう. また, 患者の習癖や, 固有咬合力の違いによって, 残存歯の延命効果が, 期待されたほどに発揮できないこともある. さらに, オーバーデンチャーを選択する時期が遅すぎたのではないかと考えられる症例も散見される. 力のコントロールと, 支台歯の負担能力の確実な予測は, 今後の重要な課題と思われる.

Apoptosis is a physiological form of cell death that is responsible for the deletion of cells. Epidermal keratinocytes are supposed to be regulated by cell proliferation and cell death leading to structural homeostasis. Psoriatic skin shows marked thickening of the epidermis, suggesting the imbalance of the homeostasis, which might be related to abnormal apoptotic process. We investigated the expression of various apoptosis-related molecules in the psoriatic hyperproliferative epidermis. Real time quantitative RT-PCR analyses revealed that mRNAs of Fas, Bcl-xL, Bax and ICAD (inhibitor of caspase 3-related DNase) of the psoriatic involved epidermis were increased by 4.2-, 2.8-, 2.6- and 5.6-fold, respectively, compared with the uninvolved epidermis. In contrast, Bcl-2 expression in the involved epidermis was one-third suppressed compared with the uninvolved epidermis. No significant difference in the expression of mRNAs of Fas ligand or CAD (caspase 3-related DNase) was detected between the involved and uninvolved epidermis. Western blot analysis and immunohistochemical studies showed compatible results obtained by RT-PCR analyses. Although active caspase 3 was slightly increased in the involved epidermis, apoptotic cells were marginally detected. These results indicate that psoriatic epidermis shows aberrant expression of apoptosis-related molecules representing suppressed apoptotic process, which might be related to characteristic histopathology.

We describe two cases of pleomorphic angioleiomyoma. In one case, a 46-year-old man presented with a single nodule on his scrotum of 1 year's duration, and in another, a 38-year-old woman presented with a single nodule on her right knee of 1 year's duration. In both cases, histopathologic examination showed a well-circumscribed nodule composed of smooth muscle and numerous veins and capillaries. Contrary to the ordinary angioleiomyoma, marked nuclear pleomorphism was noted. Although mitoses were rare, immunohistochemistry revealed many tumor cells that were positive for proliferating cell nuclear antigen, Ki-67, and p53, indicating that the pleomorphic appearance does not simply represent a degenerative change of some tumor cells.

Involucrin is one of the precursor proteins of the cornified cell envelope that is formed beneath the cell membrane during terminal differentiation of keratinocytes. 12-O-tetradecanoylphorbol-13-acetate (TPA), which is a potent protein kinase C (PKC) activator, induces terminal differentiation of keratinocytes. We previously demonstrated that involucrin promoter activity is stimulated by TPA in cultured fetal rat skin keratinocytes. PKC is a large family of proteins and keratinocytes containing five PKC isozymes: α, δδ, e, ηη, and ζζ. In order to determine the role of the PKC isozyme(s) on involucrin gene expression, we constructed the chloramphenicol acetyl transferase (CAT)-involucrin promoter expression vector by connecting the 5′-upstream region of the human involucrin gene containing the untranslated first exon to the CAT reporter gene. The CAT-involucrin promoter expression vector was transfected with various PKC isozyme expression vectors into SV40-transformed human keratinocytes (SVHK cells). Transfection of the CAT-involucrin promoter expression vector with PKC-α or PKC-ηη expression vectors resulted in a significant increase in the TPA-dependent involucrin promoter activity. The PKC inhibitor, 1-(5-isoquinoline-sulfonyl)-2-methyl piperazine dihydrochloride, inhibited the promoter activity stimulated by TPA. Transfection of PKC-δδ, -e, and -ζζ had no effect on the involucrin-promoter activity. Although the promoter activity was stimulated by transfection of PKC-γγ, TPA did not enhance the promoter activity in the PKC-γγ-transfected SVHK cells. Previously we showed three AP-1 binding sites (AP1–1, –2, and –3) on the involucrin promoter region. Both the basal and the TPA-stimulated involucrin promoter activities were suppressed by deleting the AP1–1 site (–119 to –113) that is the most proximal to the transcription start site. The deletion of AP1–2 (–297 to –303) or AP1–3 (–447 to –453) did not affect the involucrin promoter activity. Gel retardation analyses disclosed that TPA stimulated the specific DNA binding of the nuclear protein(s) of control, PKC-α, or PKC-ηη-transfected SVHK cells, but not of PKC-γγ-transfected cells. Addition of anti-c-Jun and anti-c-Fos antibodies decreased the specific protein-DNA complex band with a concomitant appearance of supershifted bands. These results indicate that PKC, specifically PKC-α and PKC-ηη, mediates the TPA-dependent activation of involucrin gene expression of SVHK cells. PKC-γγ, which is not present in keratinocytes, also induces involucrin gene expression in a TPA-independent manner, when introduced into SVHK cells. Key word: cornified cell envelope. J Invest Dermatol 110:218–223 1998

The coercive field of permanent magnets decreases with increasing grain size. The grain size dependence of coercivity is explained by a size dependent demagnetizing factor. In Dy free Nd$_2$Fe$_{14}$B magnets the size dependent demagnetizing factor ranges from 0.2 for a grain size of 55 nm to 1.22 for a grain size of 8300 nm. The comparison of experimental data with micromagnetic simulations suggests that the grain size dependence of the coercive field in hard magnets is due to the non-uniform magnetostatic field in polyhedral grains.

A method of predicting fatigue strengths using fracture mechanics on noched components of ferrous sintered materials is investigated. By applying Lukas's formula for evaluation of AK and a intrinsic crack model for small crack propagation on notched components, a simple formula for predicting fatigue limits was derived. This method requires three material properties: the fatigue limit of smooth specimen, the threshold stress intensity range for long crack, and the threshold value of the effective stress intensity. For experimental verification, a notched specimen for fatigue tests as sintered was designed, and fatigue tests were conducted with notched specimens of ferrous sintered materials with two different pore sizes. The predicted fatigue limits are comparatively in good agreement with the experimental results.

The transrepressing function of the N-myc protein is due to the distinct domains located at the N-terminus. In this report we introduced various point mutations around the myc boxes of the N-myc protein to examine whether the phosphorylation of the protein affected its transrepressing function. Serine (Ser) residues located at amino acid numbers 12, 31, 51, and 65 were changed to leucine or arginine, and the expression vectors of the mutant proteins were transfected to HeLa cells together with the luciferase gene linked to the MHC class I gene. Among the mutants, only the N(51)-myc carrying mutation at Ser(51), a target for mitogen-activated protein kinase (MAP kinase), lost the repression activity, while the other mutant proteins preserved it. Formation in vitro of the specific nucleoprotein complexes on the H2TF1/NFkappaB element, a major target for transrepression by N-myc protein, was interfered by the wild-type N-myc protein, but not by the Ser(51)-mutated protein. The results suggest that the phosphorylation of the N-myc protein at Ser(51) by MAP kinase is required for the transcriptional repression activity of the protein.

A cDNA encoding M2-type pyruvate kinase from mouse was cloned and its nucleotide sequence was determined. The cDNA encoded a protein containing 531 amino acids, the nucleotide and amino acid sequences of which were 93.2% and 98.1%, respectively, homologous to those of rat M2 pyruvate kinase. Expression of the pyruvate kinase in mouse embryonal carcinoma P19 cells altered according to differentiation stages; high at undifferentiated and low at differentiated stages.

An attempt has been made to review a clinical stage of recording the jaw relationship for removable partial dentures. The basic factors for registration of maxillo-mandibular relation have been reviewed from a view point of the functional characteristics of load supporting tissues and mandibular movements by M. Kishi in chapter II. T. Goto has dealed with the role of remaining teeth in the recording the jaw relationship in chapter III. E. Mushimoto has pointed out registration errors of jaw relation with the deviated mandible in molar loss. And E. Nagaoka has presented fundamental date for determination of occlusal plane and vertical dimension using film image information in chapter V. A. Manabe has detailed on possible errors accompanied with clinical procedures during recording the jaw relationship and on measures for avoiding them in chapter VI. Further, the clinical procedures to improve an accuracy of the bite taking and of its representation on an articulator has successfully been shown by T. Miyata in chapter VII. Fujii wrote general introduction and summary.

It is now well recognized that syringomatous hyperplasia with squamous syringometaplasia is a type of pseudoepitheliomatous hyperplasia responding to a variety of stimuli. We report a case of linear scleroderma with this process. Histopathology of the lesion showed numerous solid and cystic epithelial structures with squamous metaplasia within typical sclerodermatous skin lesions. Although the pathogenesis of the process remains unclear, dermal-derived growth factors in scleroderma and/or the mechanical effect of sclerosis could stimulate the proliferative response of eccrine epithelium. To the best of our knowledge, the association of syringomatous hyperplasia with eccrine squamous syringometaplasia and linear scleroderma has not been described previously.

We present a case of basal cell carcinoma on the buttock. The patient was a 30-year-old man who noticed a gradually enlarging asymptomatic dark reddish nodule of one year duration on his right buttock.Histopathology showed solid type basal cell carcinoma with markedly pigmentladen tumor cells. Surveillance of the literature disclosed 25 Japanese basal cell carcinoma cases of gluteal - perianal location, among which our case was the youngest one. [Skin Cancer (Japan) 2000; 15: 85-87]

We analyze the dipolar energies of Nd-Cu-infiltrated Nd-Fe-B nanocrystalline magnets during magnetization reversals by visualizing the magnetic dipolar interactions. Non-magnetic phases from the grains were identified by analyzing the element-specific magnetization distribution images taken with scanning transmission X-ray microscopy. The magnetic dipolar interactions were calculated from the interactions between the magnetization at each point and those at other points in the scanning transmission X-ray microscopy images. We present the dipolar energy distributions in Nd-Cu infiltrated nanocrystalline Nd-Fe-B magnets and compare them with those in nanocrystalline Nd-Fe-B magnets without Nd-Cu infiltration. The interplay between the exchange and dipolar interactions in Nd-Fe-B magnets is found to be essential for obtaining high coercivities.

When adapted for use in automotive engines, CNG and LPG are considered environmentally friendly compared to gasoline or diesel fuel. However, when these gaseous fuels are used, wear of the valve seat insert and valve face increases if materials meant for use with gasoline are adopted. In comparison to a gasoline engine, the oxide membrane that is formed on the sliding surfaces of the valve face and valve seat insert is limited. As a consequence, adhesion occurs and increased wear of these components is the result. Based on analysis materials that are more compatible with these gaseous fuels were developed.

This paper describes large eddy simulation (LES) of the internal flows of a high-specific-speed mixed-flow pump at low flow-rate ratios over which measured head-flow characteristics exhibits weak instability. In order to deal with a moving boundary interface in the flow field, a form of the finite-element method in which overset grids are applied from multiple dynamic frames of reference has been developed. The method is implemented as a parallel program by applying a domain-decomposition programming model. The predicted pump heads reproduce the instability and agree quantitatively well with their measured equivalents although the predicted stall takes place at somewhat lower flow-rate ratio than in the measurements. The phase-averaged distributions of the meridional- and tangential-velocity components at the impeller’s inlet and exit cross-sections were also compared with those measured by a Laser-Doppler velocimetry (LDV). Reasonably good agreements have been obtained between the computed and measured profiles. The developed LES program thus seems to be a promising design tool for a high specific-speed mixed-flow pump particularly for off-design evaluations.Copyright © 2002 by ASME

Multiphase nano-structured permanent magnets show a high thermal stability of remanence and a high energy product while the amount of rare-earth elements is reduced. Non-zero temperature micromagnetic simulations show that a temperature coefficient of remanence of −0.073%/K and that an energy product greater than 400 kJ/m3 can be achieved at a temperature of 450 K in a magnet containing around 40 volume percent Fe65Co35 embedded in a hard magnetic matrix.

We studied NdFe11TiNx compounds as permanent magnet materials. The (Nd0.7,Zr0.3)(Fe0.75Co0.25)11.5Ti0.5N0.52 powder that contained a limited amount of the α-(Fe, Co) phase shows fairly good magnetic properties, such as a saturation polarization (Js) of 1.68 T and an anisotropic field (Ha) of 2.88 (Law of approach to saturation) – 4.0 MA/m (Intersection of magnetization curves). Both properties are comparable to those of the Nd2Fe14B phase.

Permanent magnet material with high maximum energy product is demanded for industrial applications such as high-efficiency motors for hybrid and electric vehicles. Maximum energy product depends on the coercive force and the saturation magnetization. In order to achieve the high maximum energy product, current Nd-Fe-B magnets are doped with heavy rare-earth element Dy to enhance the coercive force at the expense of reducing the saturation magnetization. Viewed from another side, a supply of Dy is highly concerned because of the inequitable distribution of rare-earth resources on the Earth. Therefore, development of a Dy-free Nd-Fe-B magnet is desired. In this context, we have fabricated the Dy-free Nd-Fe-B nanocrystalline magnet and performed the small-angle neutron scattering (SANS) experiment to reveal the mechanism of its coercive force. Hot-deformed Nd-Fe-B nanocrystalline magnets with and without the diffusion process of Pr-Cu eutectic alloy were prepared [1]. Coercive forces were 1.46 T and 2.64 T for as-deformed and Pr-Cu infiltrated sample, respectively. Magnetic field dependent SANS experiment was performed to observe the magnetization reversal process. The reversal magnetic field was swept from 0 T to 5 T. SANS intensities exhibit maxima around the coercive force for both as-deformed and infiltrated sample, which indicates the evolution of the magnetic domain structure. In addition, suppressed intensity variation in infiltrated sample compared to that in as-deformed sample indicates the magnetic isolation of Nd2Fe14B grains, which is responsible for the high coercive force. We will compare the results for Pr-Cu infiltrated sample with Nd-Cu infiltrated one [1]. This work was supported by the Elements Strategy Initiative Center for Magnetic Materials under the outsourcing project of the MEXT, Japan. We thank HZB for the allocation of neutron beamtime (Proposal No. MAT-04-2110). The sample preparation was performed under the MagHEM project.

In this study, Nd(Cu)-Fe-B single layer thick films (up to 5 μm) have been prepared by triode sputtering and the effect of excess Nd and Cu content on the magnetic properties and microstructures have been investigated. The films were deposited at 450 °C and depending on the Nd and Cu content, they are either amorphous or crystalline in the as-deposited state. All films were submitted to an ex-situ rapid thermal annealing (500 °C/10 min). While films with a lower Nd and Cu content are characterized by a homogeneous microstructure, those with a higher Nd-Cu content have a wide distribution in grain size (in some cases, peculiar flower-like structures are formed close to the substrate). The inhomogeneous microstructure, together with direct crystallization in the as-deposited state in high Nd-Cu containing films, is attributed to an exothermic reaction. The highest coercivity (2.75 T) is achieved for the lower Nd (17.5 at. %)-Cu (1.5 at. %) content, higher Nd (up to 35 at. %)-Cu (up to 3 at. %) content leading to a reduction in both coercivity and degree of texture.

We analyzed the dipolar energy of Nd-Fe-B nanocrystalline magnets in magnetization reversal process through visualizing magnetic dipolar interaction. We obtained magnetization distribution images experimentally by using scanning transmission X-ray microscopy (STXM). The magnetic dipolar interaction was calculated by the interaction between the magnetization at each point and those at the other points on the STXM image. We showed the dipolar energy in the nanocrystalline Nd-Fe-B magnets and compared it with the exchange energy at various applied fields. Our results indicated the significance of the dipolar energy in magnetization reversal process.

The magnetic reversal behaviors of single domain sized Nd-Fe-B permanent magnets, with and without isolation between the Nd2Fe14B grains, was clarified using small-angle neutron scattering (SANS). The SANS patterns obtained arose from changes in the magnetic domains and were analyzed using the Teubner–Stray model, a phenomenological correlation length model, to quantify the periodicity and morphology of the magnetic domains. The results indicated that the magnetic reversal evolved with the magnetic domains that had similar sized grains. The grain isolation enabled us to realize the reversals of single domains.

Using scanning transmission X-ray microscopy (STXM), in this report we visualized the magnetic dipolar interactions in nanocrystalline Nd-Fe-B magnets and imaged their magnetization distributions at various applied fields. We calculated the magnetic dipolar interaction by analyzing the interaction between the magnetization at each point and those at the other points on the STXM image.

ELSEVIER, Nakamura, S; Takahashi, H; Kinouchi, M; Manabe, A; Ishida-Yamamoto, A; Hashimoto, Y; Iizuka, H, JOURNAL OF DERMATOLOGICAL SCIENCE, 25(2), 139-149, 2001. author, SV-40 transformed human keratinocytes (SVHK cells) were stimulated with epidermal growth factor (EGF)2 and ultraviolet B (UVB) irradiation. Following the stimulation, cell growth, apoptosis, and the activities of mitogen-activated protein (MAP) kinase families were analyzed. EGF (100ng/ml) increased SVHK cell number compared with control cells cultured in serum-free DMEM medium. The EGF-stimulated cells did not show DNA fragmentation. In contrast, UVB irradiation (40mJ/cm2) markedly decreased viable cell number, that was accompanied with DNA fragmentation. EGF stimulated extracellular signal-regulated kinase (ERK) and stress-activated protein kinase/c-Jun N-terminal kinase (JNK). Following the EGF stimulation, phosphorylated ERK and JNK were detected by phospho-p42/44 MAP kinase antibody and phospho-SAPK/JNK antibody, respectively. On the other hand, UVB irradiation stimulated the phosphorylation of p38 and JNK but not of ERK. The stimulation of ERK and JNK induced by EGF was observed earlier than the stimulation of p38 and JNK induced by UVB. PD98059, a specific MAP kinase kinase (MAPKK) 1 (also referred to as MEK1) inhibitor, inhibited EGF-dependent cell proliferation, that was associated with the inhibition of ERK and JNK phosphorylation. In contrast, UVB-induced overall cell death was not significantly affected by PD98059, that inhibited phosphorylation of JNK but not of p38. PD98059, however, significantly augmented UVB-induced cell death earlier time points (30min - 2 h). These results indicate that ERK and JNK are activated following EGF stimulation, that might be associated with cell proliferation. On the other hand, UVB-induced apoptosis seems to be mostly associated with the activation of p38. JNK stimulation might provide an anti-apoptotic tonus during the UVB-induced, p38-associated SVHK cell death.