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Objective The purposes were to compare the practice effect of stimulated whole saliva collection (SWSC) with unstimulated whole saliva collection (UWSC), and to investigate the validity of the tests as a criterion in the diagnosis of Sjogren's syndrome (SS), allowing for the practice effect. Study design SWSC (n = 34) or UWSC (n = 27) was performed 3 times on healthy volunteers to investigate practice effects; then the differences among the 3 measurements were analyzed. For evaluating the validity of the tests, UWSC and SWSC were performed alternately on 28 SS patients and 34 control subjects, all of whom had had a practice SWSC before the actual test; then the sensitivity and specificity of both tests as a criterion in the diagnosis of SS were calculated. Results A practice effect was observed for SWSC, but not for UWSC. When an orientation measurement was performed before the actual SWSC, there was no statistically significant difference between the accuracy of SWSC and UWSC as a criterion in the diagnosis of SS. Conclusion If an orientation measurement is performed before the actual measurement, SWSC can be as valid a test for sialometric evaluation in the diagnosis of SS as UWSC.

We have developed a limited slip differential (BCDiff.) which gives driving stability and high traction performance of the vehicle. This device is a new structural limited slip differential which limits the differential motion by rolling friction of the ball. We clarified the principle of the differential motion and the limiting differential, and established the calculation formula.

歯肉癌におけるT分類はT4の基準に問題があり, 解釈が分かれる。本論文ではUICC分類, 頭頸部分類, 下顎管分類, 洞底分類についてその妥当性を比較検討した。対象は下顎歯肉癌は24施設から集積した1187例で, 上顎歯肉および硬口蓋癌は単一施設の37例で, T別症例分布, 生存率, 多変量解析, 治療法選択などとの関係で解析した。結果はUICC分類では大多数がT4になり, あまりT分類の意味をなさない。頭頸部分類では分布や生存率で多少是正されるが不十分であり, 下顎管分類や洞底分類で大いに改善された。下顎歯肉癌の多変量解析から下顎管分類が表面的な腫瘍の拡がりがTを規定するというUICC分類の原則をよく反映しており, 骨吸収様式と程度の分析から下顎管分類が治療法選択上よい基準を示した。これら検索から下顎歯肉については下顎管分類が, 上顎歯肉, 硬口蓋では洞底分類がT分類法としてもっとも妥当なものと結論される。

2-(Chalcogeno)-1-ethoxyallylic cations 4A are easily generated from the reactions of 2-(chalcogeno)-1-ethoxyprop-1-en-3-ols 2a−e or 2-(chalcogeno)prop-2-enal acetals 3a−c and TMSOTf and reacted with various nucleophiles to give the adducts 5a−8a, 5b−11b, and 5c−e regio and stereoselectively. 2,4-Bis(chalcogeno)penta-2,4-dienal acetals 16a,c and the 2,4,6-tris(phenylthio)hepta-2,4,6-trienal acetal 20c also gave the dienones 17a,c and 21c in good yields. Furthermore, the intramolecular cyclization of the alkenyl alcohols 25a,b and the 2,4-dienal 2,4-dinitrophenyl hydrazones 29a−c afforded the tetrahydrofurans 26a,b and 3,5-bis(chalcogeno)pyridines 30a−c, respectively.

The α-chalcogene-substituted formylolefinations of ketones and aldehydes proceeded using 1-lithio-2-ethoxyvinyl chalcogenides/PPSE or TMSOTf to produce the α-chalcogenoformylolefinated products 4a−...

Addition of nucleophiles such as dimethylsulfoxonium methylide and ButOOLi to the conjugate enyne sulfones 4–7, 11–14, 27–28 and 31 occurs at the β-position to the phenylsulfonyl group to give the corresponding cyclopropanes 15–17 and 19–22 and the oxiranes 33–38 in high yields. The thermal reactions of vinyloxirane 36 show an oxy-Cope rearrangement to give 2-phenylsulfonylphenol 39.

Kinesiologic analysis of gait disorders, postural instabilities and abnormal movements is quite difficult to assess objectively by clinical observation, such as by specific scale and video recordings. In this study, we reported one of the aspects of the usefulness of three-dimensional motion analysis (Vicon Systems, Oxford, United Kingdom), which can measure inclusive data of movement disorders and substitute for conventional assessments. A 49-year-old man who had various dystonic symptoms, mainly on his left side of the body, responded well to deep brain stimulation (DBS). The examination quantified how the involuntary movements or other symptoms with dystonia changed before and after treatments.

Addition of nucleophiles such as dimethylsulfoxonium methylide and ButOOLi to the conjugate enyne sulfones 4–7, 11–14, 27–28 and 31 occurs at the β-position to the phenylsulfonyl group to give the corresponding cyclopropanes 15–17 and 19–22 and the oxiranes 33–38 in high yields. The thermal reactions of vinyloxirane 36 show an oxy-Cope rearrangement to give 2-phenylsulfonylphenol 39.

The α-chalcogene-substituted formylolefinations of ketones and aldehydes proceeded using 1-lithio-2-ethoxyvinyl chalcogenides/PPSE or TMSOTf to produce the α-chalcogenoformylolefinated products 4a−...

2-(Chalcogeno)-1-ethoxyallylic cations 4A are easily generated from the reactions of 2-(chalcogeno)-1-ethoxyprop-1-en-3-ols 2a−e or 2-(chalcogeno)prop-2-enal acetals 3a−c and TMSOTf and reacted with various nucleophiles to give the adducts 5a−8a, 5b−11b, and 5c−e regio and stereoselectively. 2,4-Bis(chalcogeno)penta-2,4-dienal acetals 16a,c and the 2,4,6-tris(phenylthio)hepta-2,4,6-trienal acetal 20c also gave the dienones 17a,c and 21c in good yields. Furthermore, the intramolecular cyclization of the alkenyl alcohols 25a,b and the 2,4-dienal 2,4-dinitrophenyl hydrazones 29a−c afforded the tetrahydrofurans 26a,b and 3,5-bis(chalcogeno)pyridines 30a−c, respectively.

The photo-reactions of 2,4,6-tris(phenylthio)hepta-2,4,6-trienal 1 and its 2,4-dinitrophenylhydrazone 5 gave the 2-oxa- or 2-azabicyclo[3.3.0]octa-3,7-dienes 2 and 9, respectively, via a photo-induced intramolecular tandem cyclization reaction.

Demagnetizing curves after field cooling were measured in the melt processed YBa2Cu3Ox superconductors using a vibrating sample magnetometer and a SQUID magnetometer. The curves showed that the samples worked as strong bulk permanent magnets. This is attributed to the strong flux pinning of the bulk superconductors and is well explained in terms of the Bean–London model. The magnetic properties of the permanent magnet can be continuously changed using the field‐cooling technique. The magnet properties of the melt‐powder–melt‐growth processed YBa2Cu3Ox with 1.5 mm thickness obtained at 5 K after field cooling in 10 kOe are as follows: the residual flux densities Br are 9.6 kG (H∥ c) and 8.5 kG (H⊥ c); the coercive forces bHc are 33 kOe (H∥ c) and 17 kOe (H⊥ c); and the maximum energy product, (BH)max, are 110 MGOe (H∥ c) and 49 MGOe (H⊥ c).

Basilar and right vertebral artery occlusion, which caused a brain stem infarction, occurred in an 11-year-old boy. There have been nine previous cases of basilar artery occlusion with steno-occlusive lesion in the vertebral artery. It is suspected that dissection of the vertebral artery at the atlantoaxial level and a gradual progression of arterial dissection to the basilar artery were the major causes of this infarction.

YBaCuO prepared by the Melt-Powder-Melt-Growth (MPMG) process has high critical current density over 30,000 A/cm2 at 77K and 1T. It has been found that non-superconducting Y2BaCuO5 (211) particles dispersed in the 123 superconducting phase are responsible for high Jc values. The values of critical current densities increased with increasing the volume fraction of the 211 particles. An anomalous second peak was observed in magnetization loops for some samples which showed a broad Tc transition in AC measurements, suggesting that some kinds of defects are responsible for the peak.

While nonsuperconducting particles are known to serve as effective pinning centers in conventional superconductors, their effect in high T c superconductors is still controversial. In this paper, we give evidence that nonsuperconducting Y 2 BaCuO 5 (211) inclusions can act as pinning centers in melt processed YBaCuO superconductors even when their size is orders of magnitude larger than the coherence length.

Microstructures of two MPMG processed YBaCuO materials with and without Y2BaCuO5 (211) inclusions were investigated by transmission electron microscopy. Using the MPMG process, it is possible to change the quantity of the 211 inclusions in the YBa2Cu3O7 (123) matrix. We prepared two YBaCuO samples with 0 and 30 vol. % 211 and with respective critical current density values of 2000 and 30 000 A/cm2 at 77 K and 1 T (magnetic field parallel to the c-axis). As possible pinning centers, we found stacking faults in the 123 matrix. However, we observed no appreciable change in their number and structure by introducing the 211 inclusions. Therefore, the difference in Jc values can be attributed to the 211 inclusion itself.

The authors report a melt-powder-melt-growth (MPMG) process which results in high J/sub c/ for bulk Y-Ba-Cu-O superconductors. The Y-Ba-Cu-O pellets or powders are melt quenched. The quenched plates are crushed into powder and mixed well. The powder is then compacted into desired shapes, remelted, and slowly cooled in a thermal gradient. When the starting composition is changed from the 1:2:3 stoichiometry toward the Y/sub 2/BaCuO/sub 5/

Recent work has shown that the melt-powder-melt-grown (MPMG) high temperature superconductor YBa2Cu3O7 with Y2BaCuO5 inclusions sustains unusually high critical current in the bulk. In the present paper the magnetic irreversibility line of this material is studied by AC permeability measurements. The irreversibility line is much steeper and is moved to higher temperatures compared to single crystal YBa2Cu3O7 and the reversible region between the irreversibility line and the Hc2 line is drastically shrunk. From standard flux creep analysis the pinning energy is found to be increased by one order of magnitude as compared to YBa2Cu3O7. The measurements further show that the irreversibility temperature increases in a simple logarithmic fashion with increasing frequency. The magnetic AC field response is found to be highly nonlinear even when B ac B dc ∼10 -5 .

Pinned type II superconductors can repel magnetic fields due to flux pinning. The recently developed Melt-Powder-Melt-Growth process enabled us to introduce fine non-superconducting particles into YBa2Cu3Ox matrix and to achieve large flux pinning force. It was found that an addition of silver was effective to reduce the amount of cracking and to increase the repulsive force of the superconductors against magnets. A heavy object could be levitated above the MPMG grown YBaCuO-Ag cooled with liquid nitrogen. We have also succeeded in levitating a person.

The authors report flux pinning behavior of melt processed YBaCuO containing Y2BaCuO5(211) inclusions. Although the size of the 211 inclusions is relatively large compared to the coherence length, they can work as pinning centers. The authors present the mechanism for pinning due to large normal precipitates. While large flux creep is observed in thin films exhibiting high Jc values, flux creep rate is very small in melt processed YBaCuO having a magnitude lower Jc values, which is understandable by considering that the pinning potential of large normal precipitates is much larger than that of small pinning centers and thereby the flux motion is less affected by thermal activation.

YBa 2 Cu 3 O 7 crystals fabricated by a quench and melt growth process contain fine Y 2 BaCuO 5 particles. These fine precipitates are considered to have three beneficial effects: they suppress crack formation; they promote oxygen diffusion; and they act as pinning centres. Such crystals exhibit larger flux pinning than single crystals and their magnetic behaviour can be understood in terms of the critical state model which has been developed for conventional type II superconductors. Both transport and magnetization measurements gave J c values exceeding 30 000 A cm −2 at 77 K and 1 T. Flux creep rate is also much smaller than that of single crystals and a value of pinning energy, U , comparable to that of conventional superconductors was obtained. A theoretical estimation of the contribution of 211 precipitates to flux pinning is also presented.

A.C. susceptibility measurements have been carried out on YBaCuO prepared by the quench and melt growth process. The temperature dependence of the real component, X′, and the imaginary component, X″, of the susceptibility does not indicate the presence of weak-link regions in the sample. The superconducting transition width of X′ is very narrow and only a single peak of X″ is observed as differed from the bulk sintered materials. The observed relationship between X′ and X″ is well explained in terms of Bean’s critical state model.

We report a novel melt process, or the MPMG (Melt-Powdering-Melt-Growth) process, for YBaCuO superconductors which promises high critical current density. It is important to disperse the Y2BaCuO5 (211) phase finely in the liquid in order to promote the continuous growth of the YBa2Cu3Ox (123) phase from the melt, because the 123 superconducting phase in YBaCuO system is produced by a peritectic reaction, Y2BaCuO5 (211)+L(liquid)→2YBa2Cu3Ox (123). We employed the process of pulverizing and well-mixing the oxides after cooled from partially melted region of 1, 200°C-1, 400°C, in order to achieve the fine dispersion of the 211 phase. The MPMG process has three advantages, 1) it can achieve the fine dispersion of the 211 phase, therefore the continuous growth of the 123 phase, resulting in high critical current density, 2) it is easy to form the samples in various shapes and sizes, and 3) it is possible to control the volume fraction of 211 inclusions by simply changing the starting compositions.

Methods for preservation of the sylvian veins in the transsylvian approach have not been established because of the considerable variations. This study attempted to classify the sylvian veins to facilitate systematic dissection of the sylvian fissure for sylvian veins to be preserved. The operative anatomy of the sylvian vein was examined in 82 hemispheres. The type of drainage and the pattern of branching were investigated. The superficial sylvian vein (SSV) was classified into three types according to the number of stems draining into the dural sinus on the inner surface of the sphenoid bone: The SSV was absent or hypoplastic in eight cases, the SSV was single in 38 cases, and the SSV was double in 36 cases. The SSV drained into neither the sphenoparietal sinus nor the cavernous sinus in nine cases. An anastomosis between the SSV and the deep middle cerebral vein (DMCV) was observed in 42 cases. The frontobasal bridging vein (FBBV) drained into the sphenoparietal sinus in 47 cases. The type of connection was further subdivided into four types according to the connections with the DMCV and FBBV. The venous anatomy of sylvian fissure indicates that dissection (skeletonization) of the main stem of sylvian veins from the temporal lobe should be performed to preserve the tributaries from the frontal lobe.

The dynamic magnetic flux behavior in YBa2Cu3Ox crystals made by the melt process was observed by using the Faraday effect of an iron garnet film with stripe magnetic domains. It was found that the overall flux gradient was in good agreement with that predicted by the critical state model. However, some samples contained a region where flux could not easily penetrate, indicating a large flux pinning force.

We report two patients with occlusive cerebrovascular disease who were examined by means of benzodiazepine receptor SPECT(BZR-SPECT) with 123I-iomazenil (IMZ) before extracranial-intracranial bypass surgery (EC/IC bypass). Preoperative low perfusion areas detected by cerebral blood flow SPECT (CBF-SPECT) were divided into two parts on BZR-SPECT images. In the low perfusion areas where the BZR were preserved, regional cerebral blood flow (rCBF) increased on postoperative CBF-SPECT, but where the BZR were not preserved, rCBF did not increase on postoperative CBF-SPECT. On visual inspection, the SPECT images of postoperative CBF-SPECT appeared similar to those of preoperative BZR-SPECT. For evaluation of the ischemic brain condition itself, instead of the cerebral metabolism, the distribution and activity of cerebral neurons indicated by BZR-SPECT with IMZ might be utilized.

Magnetization and the spatial variation of magnetic flux in thin film samples of YBa2Cu3Ox were studied by using a high contrast magneto-optical observation method(HICOM). The demagnetizing effect in the mixed state was also investigated in comparison with ferromagnetic materials. The magnetic flux distribution conformed to the critical state model in a YBa2Cu3Ox thin film made by laser deposition. The trapped flux in the sample with high Jc showed the nature of permanent magnet. In particular, a thin film magnet with perpendicular magnetization could be realized because the flux density in the center of the sample was not reduced by the demagnetizing field. However, the flux gradients in the edges of the sample were changed following the critical state determined by the demagnetizing field.

Magnetization of non-ideal type II superconductors can be analyzed by using the critical state model on the assumptions that the critical current density is independent of the external field and that a sample is an infinite thin flat plate. However, in a real case, the critical current density is considered to be dependent on the magnetic field and a sample is not an infinite thin flat plate. Therefore, we calculated magnetization curves considering the two dimensionality of the sample and the magnetic field dependence of J c .

The dynamical magnetic flux behavior in MPMG-processed YBaCuO was observed using the motion of stripe magnetic domains on an iron garnet film placed on the specimen. Optical observation of the domain structure in the iron garnet film clearly reveals the magnetic flux expulsion, penetration, and trapping and the magnetic field distribution. It was found that the flux motion reflected the uniform distribution of Y2BaCuO5 inclusions introduced in the MPMG-process and was in good agreement with that predicted by the critical state model.

An extremely large levitation force of 90N and a suspension force of 25N were achieved in Ag-doped YBaCuO fabricated by the Melt-Powder-Melt-Growth process using a repulsive and an attractive force between the superconductor and a 0.4T rare-earth magnet at 77K. The combination of a large Jc value and large shielding current loop is the source of such a large suspension or levitation force.

The YBaCuO prepared by the Melt-Powder-Melt-Growth (MPMG) process contains fine Y2BaCuO5 (211) inclusions embedded in the YBa2Cu3Ox matrix. Flux pinning force can be increased with increasing the volume fraction of the 211 inclusions. While MPMG processed Y1.5Ba2.25Cu3.25Ox which contains 25 volume % 211 inclusions exhibits a Jc value exceeding 3×104A/cm2 at 77K and 1T, YBa2Cu3Ox which contains no 211 exhibit a Jc value of 3×103A/cm2 at the same condition. Flux creep can also be reduced significantly by the 211 doping. These results support that the 211 inclusions can work as pinning centers. Theoretical estimation of flux pinning force due to the 211 inclusions was in good agreement with the experimental results. We also present the results of microstructural observation for MPMG processed YBaCuO with an emphasis on structural defects which can work as pinning centers.

Magnetization properties of YBaCuO samples prepared by melt-powder-meltgrowth (MPMG) process are different from those of the sintered samples, because the MPMG processed sample does not have weak-links and the shielding current flows around the whole sample. Anisotropy of Jc was estimated from M-H hysteresis curves, using Bean’s model. As a result, the MPMG processed YBaCuO sample has no weak-links, a large pinning force, and a small anisotropy of close to 3:1.

The photo-reactions of 2,4,6-tris(phenylthio)hepta-2,4,6-trienal 1 and its 2,4-dinitrophenylhydrazone 5 gave the 2-oxa- or 2-azabicyclo[3.3.0]octa-3,7-dienes 2 and 9, respectively, via a photo-induced intramolecular tandem cyclization reaction.

We report a novel melt process for YBaCuO superconductors that leads to high Jc. Since the superconducting phase in YBaCuO system is produced by a peritectic reaction: Y2BaCuO(211) + L(liquid) → 2YBa2Cu3Ox(123), it is essential to finely disperse the 211 phase in liquid to promote the continuous growth of the 123 phase. In order to achieve fine dispersion of 211 phase, we employed pulverizing and mixing process after cooled from partially melted region. The process enables fine dispersion of Y2O3 and/or 211 phase in liquid and therefore the continuous growth of the 123 phase, resulting in high Jc.