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Background: There have been reported about impacted tooth[1,2,3], but a very few literature about extraction technique using bone osteotomy. Bone osteotome is routinely used in various oral surgeries. We describe a technique of a unique bone osteotome technique for extraction of palatally inclinated maxillary impacted tooth. Methods: We occasionally encounter the patient with tooth crown of impacted tooth inclinated from the buccal site toward the palatal site. When the use of an elevator and forceps is difficult due to the palatal tilted and interference of neighboring teeth, tooth extraction is a challenge.Using this osteotome from the buccal site causes the canine to easily rise out of the socket in the palatal direction. Results and Conclusion: This bone osteotome technique for extraction of palatally inclinated maxillary impacted tooth was very useful and convenient.This is because the impacted canine can be removed with a bone osteotome, a minimally invasive surgical instrument. No appreciable disadvantages are noted with this bone osteotomy. Keywords: Unerupted Tooth; Impacted Canine; Supernumerary Teeth

The magneto-optical readout system based on a signal transfer from videotape to magnetic garnet film has been proposed. To find the garnet film suitable for this system, we developed an analytical pattern of transfer readout. The garnet film considered has a magnetization almost in-plane but slightly inclined with respect to the film plane. On the basis of this model, when a videotape on which the bit length of 0.4 μm was recorded and brought close to the garnet film, the tilt angle of magnetization was estimated to be about 5 degrees for the garnet film with thickness of 0.6 μm, magnetization of 3 × 10-2 Wb/m2, and saturation field of 39 kA/m. The transfer of bit patterns from videotape to garnet film was demonstrated by using a polarizing microscope. The dependence of signal level on bit length obtained by the readout experiment with laser beam in which videotape was moved agreed well with that predicted by calculation.

An insulator does not conduct electricity, and so cannot in general be used to transmit an electrical signal. However, the electrons within an insulator possess spin as well as charge, so it is possible for them to transmit a signal in the form of a spin wave. Kajiwara et al. have now developed a hybrid metal–insulator–metal structure in which an electrical signal in one metal layer is directly converted to a spin wave in the insulating layer. This wave is then transmitted to the second metal layer, where the signal can be directly recovered as an electrical voltage. The observation of voltage transmission in an insulator raises the prospect of insulator-based spintronics and other novel forms of signal delivery. An insulator does not conduct electricity, and so cannot in general be used to transmit an electrical signal. But an insulator's electrons possess spin in addition to charge, and so can transmit a signal in the form of a spin wave. Here a hybrid metal–insulator–metal structure is reported, in which an electrical signal in one metal layer is directly converted to a spin wave in the insulating layer; this wave is then transmitted to the second metal layer, where the signal can be directly recovered as an electrical voltage. The energy bandgap of an insulator is large enough to prevent electron excitation and electrical conduction1. But in addition to charge, an electron also has spin2, and the collective motion of spin can propagate—and so transfer a signal—in some insulators3. This motion is called a spin wave and is usually excited using magnetic fields. Here we show that a spin wave in an insulator can be generated and detected using spin-Hall effects, which enable the direct conversion of an electric signal into a spin wave, and its subsequent transmission through (and recovery from) an insulator over macroscopic distances. First, we show evidence for the transfer of spin angular momentum between an insulator magnet Y3Fe5O12 and a platinum film. This transfer allows direct conversion of an electric current in the platinum film to a spin wave in the Y3Fe5O12 via spin-Hall effects4,5,6,7,8,9,10,11. Second, making use of the transfer in a Pt/Y3Fe5O12/Pt system, we demonstrate that an electric current in one metal film induces voltage in the other, far distant, metal film. Specifically, the applied electric current is converted into spin angular momentum owing to the spin-Hall effect7,8,10,11 in the first platinum film; the angular momentum is then carried by a spin wave in the insulating Y3Fe5O12 layer; at the distant platinum film, the spin angular momentum of the spin wave is converted back to an electric voltage. This effect can be switched on and off using a magnetic field. Weak spin damping3 in Y3Fe5O12 is responsible for its transparency for the transmission of spin angular momentum. This hybrid electrical transmission method potentially offers a means of innovative signal delivery in electrical circuits and devices.

A 128 by 128 magneto-optic spatial light modulator (MOSLM) with single magnetic domain pixels, which is driven by using only drive lines without external bias coil, is described. The array of pixels was formed with Bi substituted iron garnet film grown by liquid phase epitaxial (LPE) method. Since the magnetic switching field of the pixels was so large owing to their growth induced magnetic anisotropy, we reduced it by annealing. Straight copper lines, which have low electrical resistance and enable to apply a homogenous magnetic field to the pixel, were used as drive lines. These improvements reduced an electric power 70% compared with conventional MOSLM and kept the pixels with a single magnetic domain after switching. Though the domain structure depended on the pulse width of current, the frame rate of 5 kHz was estimated by using optimized drive condition.

In order to greatly increase the speed at which videotapes are read, we propose an optical reading method using a magnetic garnet film. This method allows several data tracks to be read in parallel. In order to realize the optical reading of data, the magnetic garnet films need to have not only high enough resolution for all data to be transferred from the videotape, but also a large Faraday coefficient for data to be reproduced with a high carrier-to-noise ratio (CNR). We have constructed trial films with a Faraday rotation angle of approximately 5deg per micrometer film thickness when a green laser is used. The data patterns transferred from a D-3 format videotape were clearly observed using a polarizing microscope. An experiment to reproduce videotape data was carried out at a tape speed of 0.367 m/s, and a CNR of over 30 dB was achieved for a bit-length of 0.385 mum. The film had a constant real permeability over a frequency range of 40 MHz, which corresponds to a tape speed of 353x with respect to the D-3 system.

Superconducting rf cavities used as accelerating structures in particle accelerators are made from high purity niobium with residual resistance ratios greater than 250. Reactor grade niobium is also used to make wave-guide and/or end group components for these accelerating structures. The major impurities in this type of niobium are interstitially dissolved gases such as hydrogen, nitrogen, and oxygen in addition to carbon. After fabricating the niobium accelerating structures, they are subjected to heat treatments for several hours in vacuum at temperatures of up to 900 C for degassing hydrogen or up to 1400 C for improving the thermal conductivity of niobium considerably. These heat treatments are affecting the mechanical properties of niobium drastically. In this paper the variation of the mechanical properties of high purity and reactor grade niobium with heat treatments in a vacuum of {approx} 10{sup -6} Torr and temperatures from 600 C to 1250 C for periods of 10 to 6 hours are presented.

Spatial light modulator (SLM) is a real-time programmable device for modifying amplitude, phase or polarization of optical wave front by electrically controlled signals. Various types of SLMs with pixel arrays, such as a liquid crystal SLM, have been developed. Recently, SLMs have received much attention as a light modulator in holographic data storage which requires high speed SLMs for ensuring the high data transfer rate. In this field, the application of a magneto-optic SLM (MOSLM) is highly expected because of extremely fast pixel switching speed. The conventional MOSLM used a single crystal garnet with perpendicular magnetic anisotropy to switch as a binary depending on up and down magnetization. However, for an analog modulation in our concept, the direction of magnetization is gradually changed to in-plane direction, because the modulation is depending on the magnetization direction of the garnet film. A voltage driven MOSLM for analog modulation is developed using magnetostriction effect. Moreover, the MOSLM with a structure of a magnetophotonic crystal (MPC) is fabricated for the large enhancement of magneto-optical response. This report is about a current development of MOSLMs with magnetophonic crystal driven by a voltage.

A magneto-optic spatial light modulator (MOSLM) driven by an electric field was fabricated, which is multiferroic device with magneto-optical garnet layer and piezoelectric PZT one. To control the direction of magnetization of the garnet layer, a stress field induced by PZT film was applied to the garnet layer. With an external magnetic field, the pixels of the MOSLM were switched. The driving current required for the magnetization switching was remarkably reduced to 500 nA, whose value was less than 1% of a driving current of the conventional current-driven MOSLM.

A consistent theory of the spin and isospin excitations in an infinite nuclear system is formulated based on the Ward–Takahashi (W–T) relations among various many point Green's functions, which are derived from the requirement of the rotational invariance in spin and isospin space, SU(4). Collective modes are found to be six Nambu–Goldstone bosons, called spin, isospin, and spin–isospin waves, which appear as a result of the symmetry rearrangement of the SU(4) symmetry. The W–T relations are used to determine correlations among collective modes and to obtain a consistent expression for the static susceptibility beyond the random phase approximation. A consistent picture of the isovector collective excitations and their relationship to numerous experimental results is established. A partially conserved isovector current, analogous to a partially conserved axial current, in the symmetry rearrangement of isospin symmetry is established. This helps to define non-pertubatively the finite energy shift due to the explicit symmetry breaking terms.

The aim of this study was to analyze the clinical characteristics, operative management and early and late outcomes of Inflammatory abdominal aortic aneurysms (IAAAs) in our vascular service, retrospectively and to compare with the outcomes of open and endovascular aneurysm repair (EVAR) in the patients with IAAAs in literature reviews.Between January 1990 and December 2011, this series included twenty-four patients with IAAAs who underwent surgical treatment. The mean length of follow-up was 37.6 months (range 3-108). Kaplan-Meier life tables were used to calculate survival rate.Fifteen patients (60%) were symptomatic including 3 patients with hydronephrosis. Seven patients with severe symptoms underwent emergency operations. Twenty four patients underwent open surgical AAA repair. The 30 - day mortality rates were 0%. All patients had successful post operative courses and followed as outpatients in an elective situation. The ten year cumulative survival rate was 70%. The early and late mortality was the same for open repair compared to non-inflammatory AAA.IAAA compared with non-IAAA is associated with a higher incidence of preoperative morbidity, however operative mortality rates are lower. EVAR has lower early operative mortality rates, however, there are some problems such as remaining periaortic fibrosis and hydronephrosis in approximately half of IAAA patients after EVAR.

Radioisotopes have been widely used in Japan. The total number of facilities working with radioisotopes or radiation instruments reached to 5,509 in 1993. The state of supply of radioisotopes and management of radioactive wastes generated from the use of radioisotopes is described.

The prostacyclin analogue TTC-909 is incorporated in lipid microspheres and is chemically very stable. We examined the efficacy of TTC-909 on cerebral microcirculation following focal cerebral ischaemia. Focal cerebral ischaemia was produced by the occlusion of the distal middle cerebral artery in stroke-prone spontaneously hypertensive rats. Intravenous administration of TTC-909 (100 ng/kg/day) or vehicle was started 30 minutes after the occlusion and repeated for 7 days. On day 7, cerebral blood flow and blood-brain barrier permeability were measured autoradiographically. Brain oedema was estimated by the gravimetric method. The size of the infarction was calculated from area measurements on serial histologic sections. Treatment with TTC-909 resulted in significant improvement in regional blood flow in the ischaemic rim (p < 0.01) and the surrounding area (p < 0.05). With TTC-909 treatment, the increased permeability was significantly reduced in the ischaemic centre (p < 0.01) and rim (p < 0.05). A decrease in specific gravity in the ischaemic region and the remote non-ischaemic regions was prevented by the treatment (p < 0.01). We assumed that the efficacy of TTC-909 maintains the blood supply in the ischaemic area, improves disruption of the blood-brain barrier and prevents development of ischaemic oedema.

Thermoelectric generation is an essential function of future energy-saving technologies. However, this generation has been an exclusive feature of electric conductors, a situation which inflicts a heavy toll on its application; a conduction electron often becomes a nuisance in thermal design of devices. Here we report electric-voltage generation from heat flowing in an insulator. We reveal that, despite the absence of conduction electrons, a magnetic insulator LaY2Fe5O12 converts a heat flow into spin voltage. Attached Pt films transform this spin voltage into electric voltage by the inverse spin Hall effect. The experimental results require us to introduce thermally activated interface spin exchange between LaY2Fe5O12 and Pt. Our findings extend the range of potential materials for thermoelectric applications and provide a crucial piece of information for understanding the physics of the spin Seebeck effect., 19 pages, 5 figures (including supplementary information)

To prepare a pure liquid D 2 /T 2 target for muon-catalyzed fusion (μCF) experiments, 50 TBq of tritium gas was purified with gas chromatography for isotopic enrichment and with the tritide formation reaction of uranium for chemical purification. The isotopic purity of the processed tritium was as high as 99.9% and the chemical purity 99.7%. The 3 He content was 0.02% or less immediately after the preparation. A 300 mL (30 TBq) portion of pure T 2 gas was mixed with 700 mL of pure D 2 gas to be loaded into a target chamber made of stainless steel. The D 2 /T 2 mixed gas was liquefied in the target chamber by cooling with liquid helium and irradiated with pulsed μ − beams for more than 200 h. No characteristic muonic x-rays arising from impurities in the D 2 /T 2 target were observed.

By using thermo field dynamics, we studied the phase transitions of thermal squeezed states. Two critical points are obtained in certain cases. They correspond to the transitions from thermal squeezed state to pure squeezed state and to thermal state respectively.

We succeeded in growing single crystal of bis[4-dimethylamino-N-methyl-4-stilbazolium] terephthanate (BDAS-TP) by using a solution-slow-cooling technique. We obtained a broadband THz spectrum from BDAS-TP crystal.

Using methods of thermo field dynamics we develop a perturbation and renormalization procedure for thermally dissipative quantum fields. We emphasize the need to construct dissipative asymptotic fields and to treat the dissipation self consistently. From a stationarity condition we find the Bose-Einstein distribution for the number density in the zero dissipation limit. Considering a simple model with symmetry breaking we find that Goldstone's theorem is satisfied and at zero energy the Goldstone boson does not interact or dissipate, even though at finite momentum and energy the particles are dissipating. The theory should find uses in any physical process involving thermal effects.

The thermo field dynamics formulation of quantum fields in the presence of eternal Schwarzschild black holes, which was presented by Israel (1976) in the free case, is extended to the case of self-interacting fields. With this formulation, the authors calculate the dissipative coefficient for an excited quantum particle in an equilibrium distribution. The result shows that the quantum particle dissipatively disappears with an infinitesimal lifetime near the event horizon and with a constant lifetime far from the horizon.

Spatial light modulators (SLMs) are key components of collinear holographic storage. Collinear holography utilizes coaxially aligned information and reference beams which are displayed simultaneously by a same SLM for writing process, and also employs reference beam for retrieving process. We developed magneto-optic spatial light modulators (MOSLMs) which have high-speed switching and applied them to transmission-type collinear holography. In this study, we investigate performance of collinear holography with magneto-optic spatial light modulator. The Bit error rate was 8.9×10 -3 for single hologram. To examine the performance of shift-multiplexing, reconstructed image was disappeared after 3 μm shift. MOSLMs is suitable for collinear holography in terms of transfer rate especially.

This paper represents fabrication and properties of an improved current-driven 128 by 128 magneto-optic spatial light modulator (MOSLM) consists of arrayed pixels patterned with 14 micrometers square of 16 micrometers pitch. It could be driven successively only drivelines without a bias field by external coil to saturate magnetization. The magnetic pixels were embedded into the nonmagnetic substrate both to avoid magnetic switching error and to make the pixels array surface smooth. The switching field of arrayed pixels was reduced to 145Oe by annealing them to decrease the growth induced magnetic anisotropy. This value was about half of the conventional 128 by 128 MOSLMs. Moreover, copper straight drivelines were used for decreasing electric power consumption and applying a homogeneous magnetic field to the pixel. This drivelines structure enabled to switch the individual pixels reversibly keeping a single domain state, therefore, the successive driving of writing and erasing various checker patterns could be possible without bias field by external coil. The electric power consumption was decreased about 70 %. The switching speed of one pixel was 25 nanoseconds. It is more than a thousand times faster than other types of SLM, for example, 10 to 30 milliseconds for liquid crystal (LC) type, and 10-20 microseconds for micro electro mechanical systems (MEMS) type.

We found a Bi-substituted iron garnet film (Tb/sub 1.86/Bi/sub 1.14/Fe/sub 4.67/Al/sub 0.24/Co/sub 0.09/O/sub 12/) which was characterized by stable Faraday rotation against wavelength variation in the 1.55 /spl mu/m band. First, Co- and Bi-substituted iron garnet films were grown by liquid phase epitaxy (LPE), and the dependence of their Faraday rotation against wavelength variation was measured. It was found that the dependence of Bi-substituted iron garnet films on wavelength was reduced in the 1.55 /spl mu/m band due to a Faraday rotation attributable to Co/sup 3+/ ions. Faraday rotation-wavelength coefficients (FWC) of these films in the 1.53 /spl mu/m-1.57 /spl mu/m band were 0.01%/nm, or virtually zero. Also relations between FWC and film composition were discussed.

A magneto-optical spatial light modulator (MOSLM) is produced by selective area growth on garnet mask reduced in hydrogen atmosphere. The garnet film is first grown selectively on patterned (GdCa)/sub 3/(GaMgZr)/sub 5/O/sub 12/ substrate. The crystalline and domain structure of the film is analyzed by X-ray diffraction measurements and polarized light microscope, respectively. The magnetic properties are then examined by VSM measurements. From the results, it is assumed that the magnetic separation of the pixels is caused by the difference of the uniaxial magnetic anisotropy energy that depends on the crystalline structure and stress induced by the difference in the thermal expansion coefficient in each film and the defects involved in the gap section. This technique is able to prepare the pixel array separated magnetically with low switching field and to operate the MOSLM successively with no error.

This paper concerns the reduction of optical absorption loss L of Bi-substituted rare-earth iron garnet films at a wavelength of around 1000 nm for use as a 45/spl deg/ Faraday rotator of an optical isolator. First, a single crystal of Nd/sub 1.21/Gd/sub 1.74/Sc/sub 2.07/Ga/sub 2.98/O/sub 12/, with a lattice constant of 1.2619 nm, was grown by the Czochralski method. Using this crystal as a substrate, Nd/sub 1.69/Bi/sub 1.31/Fe/sub 5/O/sub 12/ film was grown by the LPE (Liquid Phase Epitaxial) method. The resultant LPE film showed a reduced optical absorption at around 1000 nm, because its optical absorption peak at around 900 nm due to the Fe/sup 3+/ crystal field transition from /sup 8/A/sub 1g/ to /sup 4/T/sub 1g/ shifted toward short wavelengths. In addition, the LPE film's Faraday rotation coefficient increased, since Nd, as Bi does, contributes negatively to the Faraday rotation. The value of L for the LPE film was found to be 2.6 dB at a wavelength of 980 nm, and 1.0 dB at 1017 nm.

An attractive future application of superconducting cavities is a TeV energy superconducting linear collider (TESLA). The substantial merits of TESLA compared to a normal conducting linear collider are to loosening of alignment tolerance and less wake field due to the lower frequency (1.3 GHz). The final focus also is easier to obtain by having the electron/positron population in bunches. TESLA demands upgrading field gradients to over 25 MV/m. KEK has been carrying out R&D on 1.3 GHz niobium superconducting cavities since 1990. So far, seven single cell cavities and two 9-cell cavities have been fabricated and tested. In parallel, input coupler design and niobium material studies are being conducted. This paper reports the present status of KEK's efforts for TESLA. >

An exact solution for random mixtures A x B 1-x of an Ising model is presented. The solution is obtained in the mean-field version of the model and exhibits a spin-glass phase transition. The explicit dependence of the critical temperature T c on the exchange integrals J AA >0, J BB >0, J AB

The purpose of this study was to examine the production of secretory component (SC) and immunoglobulin A (IgA) in the gastric mucosa with Helicobacter pylori infection and to investigate the influence of immunological reactions on various phases of infection (gastritis, intestinal metaplasia, gastric cancer). Production of SC and IgA was assessed by immunohistochemical staining in (1) endoscopic biopsy samples of H. pylori-eradicated cases (n = 25), and (2) surgically resected stomach tissues of H. pylori-positive gastric cancer cases, intestinal type (IGC, n = 25) and diffuse type (DGC, n = 25). Before eradication therapy, all samples showed positive staining of SC and IgA in epithelial cells, and IgA was also positive in plasma cells in the mucosal layer. H. pylori bacteria were positively stained for SC and IgA. After treatment, the degree of SC and IgA staining in epithelial cells was reduced with successful eradication; but with intestinal metaplasia, SC staining was positive regardless of the results of treatment. In nonmetaplastic mucosa, SC-positive cells were increased in the glandular neck zone to the surface mucosal layer; and the intensity of SC staining was increased in proportion to the degree of mucosal inflammation and IgA-positive cell aggregation. In intestinal metaplasia, SC was positive irrespective of the degree of inflammation. Most cancer foci also showed positive staining of SC, irrespective of histological type. Production of SC and IgA was thought to be a specific reaction against H. pylori infection, occurring from the early to the late stages and not limited to intestinal metaplasia. It was suggested that immunological reactions against H. pylori infection might generally be involved with the pathogenesis of intestinal metaplasia and both histological types of gastric cancer (IGC and DGC).

The clinical efficacy of percutaneous transluminal angioplasty and intra-arterial papaverine infusion for treatment of vasospasm following subarachnoid hemorrhage was investigated. Between 1990 and 1993, 84 patients were treated for cerebral vasospasm in National Defense Medical College Hospital. Angioplasty was performed for asymptomatic vasospasm in 18 patients and for symptomatic vasospasm in 12 patients. Intra-arterial papaverine infusion was performed for asymptomatic vasospasm in 10 patients and for symptomatic vasospasm in four patients. The other 40 patients were treated with standard conservative therapy including hypervolemic and hypertensive hemodilution. The outcomes of these patients were analyzed using the Glasgow Outcome Scale. The outcome tended to be better for patients treated with angioplasty, but not for those treated with papaverine infusion, than for those treated conservatively. Recurrence of vasospasm was more frequent after papaverine infusion than after angioplasty. Undesirable complications such as abrupt development of unconsciousness were experienced during papaverine infusion but not during angioplasty. We conclude that percutaneous transluminal angioplasty is superior to intra-arterial papaverine infusion for prevention and treatment of vasospasm following aneurysmal subarachnoid hemorrhage.

We report here a unique case of acute-onset dementia caused by a posterior fossa dural arteriovenous fistula (AVF), which was successfully treated by surgical resection of the isolated transverse-sigmoid sinus combined with endovascular procedures. A 70-year-old female was admitted to our hospital with acute-onset dementia and pulsatile tinnitus on the left side. CT scan revealed a low-density area in the parieto-temporal region. Cerebral angiography revealed a dural AVF of the transverse-sigmoid sinus with retrograde drainage into cerebral cortical veins. After transarterial endovascular embolization of the dural AVF, a xenon-CT scan revealed increased cerebral blood flow. Four months postoperatively, however, she was admitted to our hospital again with seizure and aphasia due to recanalizaion of the dural AVF. After trans-arterial embolization, transvenous embolization was attempted, but was unsuccessful due to inaccessibility of the isolated sinus segment. Since this patient could not be cured by endovascular embolization, an open surgical resection of the isolated sinus segment was performed. Following this, CT scans revealed that the low density area present on the first admission had disappeared. The patient's dementia resolved postoperatively. We discuss the pathophysiological mechanism by which venous ischemia due to dural AVF can cause reversible dementia.

We describe a penetrating injury of the vertebral artery caused by a nail gun. The artery was preoperatively embolized using mechanical detachable coils (MDC).