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Few studies have examined the survival rates of total hip arthroplasty (THA) with the same femoral stem, and the predictive factors leading to the revision of stemmed metal-on-metal (MoM) THA remain unknown. We determined the long-term survival rate of stemmed MoM THA compared with that of metal-on-polyethylene (MoP) bearing THA, the effect of head size and cup placement angle on revision rate, and predictors of revision.A total of 130 hips in 110 patients who underwent primary THA by the same surgeon were included. M2a-RingLoc with a metal-on-polyethylene bearing (group P, 53 hips), M2a-Taper with MoM bearing (group T, 44 hips), and M2a-Magnum with MoM bearing (group M, 33 hips) were used. The mean age at surgery was 63.1 ± 9.5 years, and the mean postoperative follow-up duration was 133.7 ± 39.1 months. Whole blood metal ion concentrations were measured preoperatively and postoperatively, and magnetic resonance imaging was performed to identify aseptic local tissue reactions (ALTRs). Kaplan-Meier survivorship analysis and multiple logistic regression analysis were performed.The THA survival rate up to the maximum postoperative follow-up period was 96.2% at 173 months, 46.6% at 179 months, and 47.8% at 145 months in groups P, T, and M, respectively, with revision as the endpoint. The stemmed MoM THA recorded a very low survival rate (p 0.001). The ALTR rates were 70.5% and 63.6% in groups T and M, respectively. The risk factor for revision was the use of MoM bearing, and there was no difference in the results based on the head size in group M. Cobalt levels continued to increase postoperatively, although they were not accurate predictors of revision.Stemmed MoM THA has a very low survival rate and should be used with caution. It is important to monitor the patient's symptoms and perform appropriate imaging to ensure timely revision.

THz electron spin resonance (ESR) measurements of the spinel compound GeCo2O4, which consists of the Co2+ pyrochlore structure, were performed. The temperature dependence measurements revealed new antiferromagnetic phases, AF1 and AF2, below TN. Moreover, a wide magnetic field range of ESR study using a single crystal at 1.8 K also revealed various field-induced phases due to the competition between the spin–lattice coupling and the spin frustration. Critical field resonances were observed at 5.0 T, 8.6 T, and 11.0 T for B//[111] and 5.1 T, 7.7 T, 11.2 T, and 13.0 T for B//[110] at 1.8 K. Although it became difficult to observe ESR above 86 K, the g-values of Co2+ ions were estimated to be g[111] = 3.34 and g[110] = 3.27 for [111] and [110], respectively, from the observed ESR mode above the saturation field at 1.8 K. Detailed frequency-field diagrams of the ESR modes at 1.8 K suggested the existence of spin–lattice coupling energy of 250 GHz (= 1.03 meV = 12 K) at the critical field resonances. The spin gap mode in the frequency-field diagram at 1.8 K showed excitation energies of E[111] = 1004 GHz (= 4.15 meV = 48 K) and E[110] = 1044 GHz (= 4.32 meV = 50 K) for [111] and [110], respectively. These results will be discussed in connection with the di-tetramer model suggested previously.

In recent years, along with the increasing demand for plastic products and the deepening of academics, mass production, weight reduction, and higher precision are progressing. In the field of design development and production technology, there is an increasing need for analysis technology related to resin flow and behavior in order to solve problems related to quality assurance such as molding defects and product strength. Especially in the resin molding process, it is an important issue to create a quality function that applies the analysis of complex multidimensional information because of the high degree of freedom in product shape and mold structure. In order to solve the quality issues regarding the strength and dimensional stability of resin materials, it is effective to apply the “Functionality Evaluation Method” in robust design which is an analytical evaluation method. In this study, we focus on the function of managing the resin filling density in the mold (the input/output relationship of the melting energy related to the resin filling characteristics) for the optimization of resin strength and dimensional stability. We propose a functional evaluation method with the ideal function of stabilizing the resin filling density based on the original definition of material mechanics. As a result of verification of the proposed method, it was clarified that it is extremely important to make the resin filling density in the mold uniform to stabilize the strength of the resin injection molded product.

Purpose: This study aimed to compare the utility score of dysplastic osteoarthritis of the hip (OA) after different surgical treatments., Methods:In this cross-sectional study, we evaluated the utility scores of 204 patients using the Short Form-6 Dimension., Results: Utility scores of all surgery types were significantly higher than those preoperatively in OA (p, Conclusions: Although THA and osteotomy are effective surgical procedures, lifetime treatment plans should be considered to avoid revision surgery as far as possible.

A dichlorosilane gas and a trichlorosilane gas in ambient hydrogen were evaluated to show their different gas flow motions in a slim vertical cold wall chemical vapor deposition reactor for the Minimal Fab system. This evaluation was performed for improving and controlling the film qualities and the productivities, using two quartz crystal microbalances (QCM) installed at the inlet and exhaust of the chamber by taking into account that the QCM frequency corresponds to the real time changes in the gas properties. Typically, the time period approaching from the inlet to the exhaust was shorter for the trichlorosilane gas than that for the dichlorosilane gas. The trichlorosilane gas was shown to move like plug flow, while the dichlorosilane gas seemed to be well mixed in the entire chamber.

Background The locomotive syndrome risk test was developed to quantify the decrease in mobility among adults, which could eventually lead to disability. The purpose of this study was to establish reference values for the locomotive syndrome risk test for adults and investigate the influence of age and sex. Methods We analyzed 8681 independent community dwellers (3607 men, 5074 women). Data pertaining to locomotive syndrome risk test (the two-step test, the stand-up test, and the 25-question geriatric locomotive function scale [GLFS-25]) scores were collected from seven administrative areas of Japan. Results The reference values of the three test scores were generated and all three test scores gradually decreased among young-to-middle-aged individuals and rapidly decreased in individuals aged over 60 years. The stand-up test score began decreasing significantly from the age of 30 years. The trajectories of decrease in the two-step test score with age was slightly different between men and women especially among the middle-aged individuals. The two physical test scores were more sensitive to aging than the self-reported test score. Conclusion The reference values generated in this study could be employed to determine whether an individual has mobility comparable to independent community dwellers of the same age and sex.

A silicon epitaxial growth process in a trichlorosilane-hydrogen system was evaluated using a quartz crystal microbalance (QCM) placed at the exhaust of a chemical vapor deposition reactor designed for the Minimal Fab. The QCM showed two types of the frequency decrease behaviors, that is, i) a quick shift due to the gas property change caused by the trichlorosilane gas introduction into the ambient hydrogen and ii) the continuous and gradual decrease due to the byproduct deposition on the QCM surface during the silicon epitaxial growth. Because both i) and ii) showed a relationship with the silicon epitaxial growth rate, the in-situ information obtained by the QCM was expected for the real time monitoring of the film deposition process.

Effective process conditions to utilize a slim vertical silicon chemical vapour deposition reactor were studied. Based on a numerical analysis taking into account the gas flow, heat and species transport, particularly over a wide range of the trichlorosilane gas concentrations from 1% to 40% in ambient hydrogen, a heavy and cold gas was shown to quickly go downward to the hot wafer surface through the slim vertical gas channel. The gas phase near the wafer was sufficiently cooled to produce a cold wall thermal condition which enabled the trichlorosilane gas consumption only at the wafer surface, even in a non-axisymmetric and non-steady condition. The slow wafer rotation, less than 30 rpm, had a considerable effect, such as that increasing the gas phase temperature gradient for suppressing the gas phase reaction.

The gas flow, heat and species transport in a slim vertical silicon chemical vapor deposition reactor for Minimal Fab were evaluated by a numerical analysis. The influences of the inlet gas flow condition on the gas flow direction and the gas phase temperature in the reactor were studied. When the gas flow rate was minimized, natural convection transports the precursor of trichlorosilane gas to the wafer surface. Because the wafer rotation, even very slow at 4 rpm, adjusted the gas flow to shrink the hot region height above the wafer, the gas phase reaction was moderated for preparing the specular surface of the epitaxial film.

We performed terahertz ESR measurements of spin frustrated spinel compound GeCo2O4 using pulsed magnetic fields of up to 40 T. A very broad EPR absorption line was observed at 86 K. The g-values at 86 K were estimated to be g=5.26±0.07, 5.16±0.12 and 4.98±0.07 for B//[111], [100] and [110], respectively. High-field ESR measurements revealed complicated phase structures and a field-induced magnetic phase below 3 K. Critical fields of magnetic phases at 1.8 K for B//[111] were observed at 1.8 T, 5.0 T, 8.6 T, 11.0 T and 12.9 T for B//[111]. An energy gap of 300 GHz (=14.4 K=1.24 meV), which was related to the lattice deformation, was observed for B//[111]. The zero field gap of ω 4 mode, which is considered to be a singlet-triplet excitation of the di-tetramer, was estimated to be 1120 GHz.

The standard for rotational alignment of the tibial component in total knee arthroplasty (TKA) remains unclear. Cases often require positioning of the tibial component, prioritizing adequate coverage of resected bone surface rather than alignment with the tibial rotational axis. We investigated tibial component position in TKA, prioritizing maximum coverage of resected bone surface, and evaluated the correlation with the tibial anteroposterior (AP) axis. We analyzed preoperative computed tomography images for primary TKA in 106 cases and 157 knees, using three-dimensional planning software. Tibial component position prioritizing maximum coverage of resected bone surface was simulated, and results were compared with the AP axis. Rotational alignment angle was defined as that between a line perpendicular to the tibial AP axis and a line connecting the posterior edge of the tibial component. The simulated tibial component was more externally rotated by a mean 4.5° ± 4.2°. The alignment angle showed normal distribution, but variability was large, ranging from 5.1° internal rotation to 16.2° external rotation. In 138 of 157 (87.9 %) knees, the tibial component was positioned in the externally rotated position with respect to the AP axis. The tibial component was aligned within the medial one-third of the patellar tendon in 122 of 157 (77.7 %) knees. The tibial component aligned using coverage prioritizing was externally rotated, although large variability was observed. Rotational alignment was optimal in 79 % of cases when the tibial component was aligned with coverage prioritizing, but hyperexternal rotation was observed in patients with severe knee deformation.

Study Design: Retrospective cross-sectional study. Purpose: To investigate the relationship between ligamentum flavum (LF) hypertrophy and lumbar segmental motion. Overview of Literature: The pathogenesis of LF thickening is unclear and whether the thickening results from tissue hypertrophy or buckling remains controversial. Methods: 296 consecutive patients underwent assessment of the lumbar spine by radiographic and magnetic resonance imaging (MRI). Of these patients, 39 with normal L4–L5 disc height were selected to exclude LF buckling as one component of LF hypertrophy. The study group included 27 men and 12 women, with an average age of 61.2 years (range, 23–81 years). Disc degeneration and LF thickness were quantified on MRI. Lumbar segmental spine instability and presence of a vacuum phenomenon were identified on ra diographic images. Results: The distribution of disc degeneration and LF thickness included grade II degeneration in 4 patients, with a mean LF thickness of 2.43±0.20 mm; grade III in 10 patients, 3.01±0.41 mm; and grade IV in 25 patients, 4.16±1.12 mm. LF thickness significantly increased with grade of disc degeneration and was significantly correlated with age ( r =0.55, p

Background Delay in fracture healing or non-union can be devastating complication. Recent studies have reported that teriparatide (TP) demonstrated effectively on callus formation and mechanical strength and zoledronate (ZA) increased the callus size and resistance at the fracture site in rat fracture model. In this study, the effects of combination therapy with low dose TP and ZA on fracture healing was evaluated. Methods From 1 week post-operation, TP (5 times a week administration) and ZA (0.1 mg/kg single administration) were administered by dividing the rats into the following five groups: TP 1 μg group {T(1): TP 1 μg/kg}, ZA group (ZA:0.1 mg/kg), TP1 μg+ZA group {T(1)+ZA: TP 1 μg/kg+ZA}, TP 10 μg+ZA group {T(10)+ZA: TP 10 μg/kg + ZA}, and control group (C: administered saline). Rt femurs were excised 7 weeks after the surgery; bone fusions were evaluated with soft X-ray images on a 4-point scale. And the histopathological examination was performed in demineralized and non-demineralized specimens. Furthermore, the Radiographic Union Scale was conducted in all specimens. Results About the bone fusions rates, C, T(1), ZA, T(1)+ZA, and T(10)+ZA groups demonstrated 20.0%, 55.6%, 70.0%, 70.0%, and 80.0%, respectively, and with 4-point scale, each group was 0.50, 1.56, 2.00, 2.60, and 2.80 points, respectively. The callus volume was significantly increased to 16.66 mm2 and 17.75 mm2 in the T(1)+ZA and T(10)+ZA groups, respectively, while 10.65 mm2 (p

A small-sized reactor for producing a silicon epitaxial film on a half-inch silicon wafer was studied, taking into account the heat transport near the wafer. The wafer temperature slowly changed over a long time period when the reflector was made of thick plates. In contrast, when thin plates were employed as the reflector material, the wafer temperature quickly increased and easily reached a steady state. Thus, the reactor parts set near the wafer should be small, slim and thin. With the help of wafer rotation and a highly heat-conductive susceptor, a symmetrical and uniform silicon epitaxial film thickness profile could be obtained. © The Author(s) 2016. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. [DOI: 10.1149/2.0251605jss] All rights reserved.

We attempted to enhance the antitumor effects of tumor lysate-pulsed dendritic cells by eliminating regulatory T cells. The combinatorial effects of dendritic cells and agonist anti-glucocorticoid-induced tumor necrosis factor receptor (anti-GITR) antibodies were investigated with respect to enhancement of the systemic immune response, elimination of regulatory T cells, and inhibition of tumor growth. To determine whether the combination of dendritic cells and anti‑GITR antibodies could enhance systemic immune responses and inhibit primary tumor growth in a murine osteosarcoma (LM8) model. We established the following 4 groups of C3H mice (20 mice in total): i), control IgG-treated mice; ii), tumor lysate-pulsed dendritic cell‑treated mice; iii), agonist anti-GITR antibody-treated mice; and iv), agonist anti-GITR antibody- and tumor lysate-pulsed dendritic cell‑treated mice.The mice that received the agonist anti-GITR antibodies and tumor lysate-pulsed dendritic cells displayed inhibited primary growth, prolonged life time, reduced numbers of regulatory T lymphocytes in the spleen, elevated serum interferon-γ levels, increased number of CD8+ T lymphocytes. The mice that received combined therapy had reduced level of immunosuppressive cytokines in tumor tissue and serum. Combining agonist anti-GITR antibodies with tumor lysate-pulsed dendritic cells enhanced the systemic immune response. These findings provide further support for the continued development of agonist anti-GITR antibodies as an immunotherapeutic strategy for osteosarcoma. We suggest that our proposed immunotherapy could be developed further to improve osteosarcoma treatment.

Chlorosilane gas transport in ambient hydrogen in a slim vertical cold wall chemical vapor deposition reactor was real-time monitored using a quartz crystal microbalance (QCM) using its behaviour responding to the properties of the gas mixture. The QCM frequency quickly decreased by introducing the trichlorosilane gas, while it slowly decreased by the dichlorosilane gas. The QCM frequency behavior was explained by the gas flow condition, such as the plug flow and recirculating flow, in the reactor. The relationship was consistent with the gas flow calculations, because the heavy and light gases could directly flow downward and recirculate, respectively, in the chamber due to natural convection. The information obtained from the QCM frequency behavior is expected to be utilized for the real-time gas monitoring and for the process design.

A chemical vapor deposition reactor for producing thin silicon films was designed and developed for achieving a new electronic device production system, the Minimal Manufacturing, using a half-inch wafer. This system requires a rapid process by a small footprint reactor. This was designed and verified by employing the technical issues, such as (i) vertical gas flow, (ii) thermal operation using a highly concentrated infrared flux, and (iii) reactor cleaning by chlorine trifluoride gas. The combination of (i) and (ii) could achieve a low heating power and a fast cooling designed by the heat balance of the small wafer placed at a position outside of the reflector. The cleaning process could be rapid by (iii). The heating step could be skipped because chlorine trifluoride gas was reactive at any temperature higher than room temperature.

A hydrodynamic bearing with non-uniform herringbone grooves has been developed for use with high-speed motor spindles. The grooves gradually become narrower, shallower and less straight (curved) towards the herringbone centre along axial direction, resulting in an increased pumping effect of the spiral grooves. The optimum dimensions of the grooves for increasing the critical bearing number were clarified theoretically, and bearings with non-uniform herringbone grooves were found to increase the critical bearing number against the half-frequency whirl up to about 50% in comparison to bearings with uniform herringbone grooves. Experiments to investigate the suitability of the proposed bearing for high-speed spindles showed that the maximum rotational speed of a spindle with this bearing was about 20% higher, close to the theoretically predicted 23%, and thus proved that application of this bearing should enable spindles to achieve faster stable rotation as theoretically expected. Copyright © 2010 John Wiley & Sons, Ltd.

A microwave single-photon detector was developed with highly-excited alkaline Rydberg-atoms in a cooled resonant cavity to search for dark matter axions. This detector belongs to a microwave single-photon counter, thus being free from the standard quantum limit (SQL). High sensitivity of the present detector system was demonstrated by measuring the thermal blackbody radiations in the cavity at temperatures as low as 70 mK where the sensitivity is below the SQL. The detection sensitivity of the present system is mainly limited by stray electric fields present in the detection region. Practical design of a new experimental scheme with a guiding electric field through the atomic-beam trajectory is here presented and discussed to avoid the effect of stray electric field and thus to improve the detection sensitivity.

The effects of dendritic cells (DCs) with low dose doxorubicin on the enhancement of the systemic immune response, including the effects on calreticulin (CRT) expression, heat shock protein 70 (HSP70) on the cell surface expression, and the enhancement of high mobility group box 1 (HMGB1) release from cancer cells, remain unclear. The present study investigated whether the combination of DCs and doxorubicin (ADM) induces immune cell death, and leads to tumor growth inhibition in a murine osteosarcoma model. To evaluate immune response activation in vivo, 4 groups of mice were established: i) untreated mice, ii) DC-treated mice, iii) ADM-treated mice, and iv) DC and ADM-treated mice. Immunological cell death and CRT, HSP70, and HMGB1 expression levels were higher in doxorubicin-treated cells than those in untreated or those treated with DCs alone. NF-κB expression was higher in the DCs after ligand activation using CRT, HSP70, or HMGB1 in vitro. Mice treated with DCs and ADM displayed an increased number of CD8+ T-lymphocytes within metastatic tumors and inhibition of metastatic growth. The expression of CRT and the release of HMGB1 from tumor tissues were increased in the ADM-treated groups. Treatment with DCs and ADM resulted in the highest serum interferon-γ levels. Combining ADM, which can induce immunogenic cell death, with DCs enhanced the systemic immune response. The findings of the present study provide further support for the continued development of antitumor agents that induce cell death and the immune response to target osteosarcoma.

Short non-coding RNAs, called microRNAs (miRNAs), regulate cell biology by affecting the expression of target genes. However, we know little about the miRNAs regulating the growth and progression of Ewing's sarcoma (ES). To identify possible oncogenic factors in ES, we used a microarray-based approach to profile the changes in the expression of miRNAs and the downstream mRNAs in five ES cell lines. One miRNA, miR‑138, was significantly downregulated, whereas the expression of focal adhesion kinase (FAK) was significantly upregulated in all tested ES cells. When miR‑138 was transfected into ES cell lines, the expression of FAK in these cells was greatly suppressed and inhibited the proliferation and mobility of ES cells. Overexpression of miR‑138 in vitro resulted in further inhibition of the cell cycle at the G1 phase and in the induction of anoikis, in a dose- and time-dependent manner. Moreover, miR‑138 overexpression in ES cells significantly suppressed the number of distant metastases in vivo. The data in the present study demonstrates for the first time a novel mechanism that regulates the expression of FAK via miR‑138 in ES cells.

Gossip-based broadcasting has recently gained popularity as a potentially effective solution for disseminating information in large-scale distributed applications. In this paper we propose a simple counter-based optimization for gossip-based broadcast protocols, aimed at enhancing reliability in the face of node failures. The basic idea is to have each node retransmit a broadcast message when the node has received the same message only a few times; a node thus can autonomously perceive the status of message dissemination and promote it when necessary. The usefulness of the technique is demonstrated through simulation results.

We have succeeded in growing single crystals of the oxide spinels GeNi 2 O 4 and GeCo 2 O 4 . Both materials have the pyrochlore lattice, and show antiferromagnetic-like order. Thus, magnetic frustrations and relevant phenomena are strongly expected. To obtain single crystals of these materials, we employed a conventional floating-zone method. For the crystal growth of GeCo 2 O 4 , no severe difficulties were found. For GeNi 2 O 4 , it was necessary to avoid intense the evaporation of GeO 2 due to the higher melting point of GeNi 2 O 4 than that of GeCo 2 O 4 . Therefore, it was quite difficult to obtain single crystals of GeNi 2 O 4 by the same procedure as GeCo 2 O 4 . We show the importance of the starting composition and crystal growth atmosphere for both spinels.

Purpose.To discuss the indications and therapeutic outcomes of synovectomy, debridement, and continuous irrigation for the treatment of pyogenic arthritis caused by intra-articular injection used in the treatment of osteoarthritis of the knee.Methods.Records of 41 patients with infectious arthritis of the knee who presented to our hospital from 1981 were reviewed. 11 of them had a history of intra-articular injection. They underwent synovectomy, debridement, and continuous irrigation using a Salem double-lumen tube after confirmation that one side of the femorotibial joint cartilage was basically healthy.Results.The infection was successfully treated in 9 of the 11 patients. Of these 9 patients, one died after 3 years and 2 underwent total knee arthroplasty after 3 and 8 years. The remaining 6 patients were followed up for 5 to 15 years. Five of them had deteriorating arthropathy, and the condition was unchanged in the others. Two of these 6 patients had pain while walking, and their Japanese Orthopaedic Association scores were 70. The remaining 4 had good knee function and reduction of pain, with a mean Japanese Orthopaedic Association score of 91 and a mean range of motion of 131 degrees.Conclusion.Arthrodesis is frequently considered the treatment for osteoarthritis if the joint destruction has affected the weight-bearing surface. However, in our experience, even when inflammatory granulation develops in the cartilage surface of one side of the femorotibial joint, good results can still be obtained by synovectomy, debridement, and continuous irrigation. After the pyogenic arthritis has subsided, if osteoarthritis has advanced and bowleg has exacerbated, further treatment options are available, such as tibial resection and even joint replacement. Continuous irrigation should be considered a feasible treatment option for pyogenic arthritis.

For young patients who have early signs of coxarthrosis resulting from acetabular dysplasia, periace- tabular osteotomies for correcting abnormal stress distribu- tion can be useful for preventing the progression of the disease. However, it is difficult to confirm the optimal transpo- sition of the osteotomized acetabular fragment. To deal with this problem, we devised a computer program to support preoperative planning. Hip images obtained by computed tomography were loaded into our program, and a three- dimensional voxel model was created. Then, osteotomy was simulated and the pressure distribution was analyzed with a rigid-body spring analysis (computational nonlinear mechani- cal analysis). The three-dimensional pressure distributions in seven dysplastic hips were evaluated before and after virtual rotational acetabular osteotomy. A peak pressure was calcu- lated for every 5° of rotation of the acetabular fragment. The peak pressure decreased gradually and increased again after- ward, indicating the optimal transposition of the acetabular fragment. The postoperative peak pressure decreased to about 40% in the most improved case. This program allows the hip joint mechanics to be evaluated easily so that the advantages and disadvantages of various surgical methods can be examined biomechanically prior to surgery.

Since 1990, a total of ten joints in nine patients with infected total knee arthroplasty have been treated in our department within 21 days of the onset of infection. Their radiographs showed no evidence of implant loosening or "moth-eaten" appearance. They underwent synovectomy, debridement, and continuous irrigation without implant removal. Continuous irrigation was maintained for 7-29 days. It was possible to retain implants in eight joints of seven patients. Two joints of two patients were removed. Pain disappeared in all eight joints in which the implants were retained. Four patients could walk with one cane; one patient could walk with one crutch. Range of motion in five joints remained over 100 degrees. We recommend synovectomy, debridement, and continuous irrigation to cure an early stage infection of total knee arthroplasty.

We report the results of measurements of the magnetic properties of single-crystal of the normal spinel GeNi 2 O 4 grown by a floating zone method. The crystal structure is face-centered cubic with a space group of F d 3 m , which is the same structure as that of the well-known geometric frustrated heavy-mass Fermi liquid LiV 2 O 4 . Highly insulating antiferromagnetic GeNi 2 O 4 possesses two Neel temperatures ( T N1 and T N2 ) of 12.1 and 11.4 K without a structural phase transition. Ni 2+ ions with integer spin ( S = 1) are located on the vertices of a three-dimensional network of corner-sharing tetrahedra. In this study, we show the magnetic susceptibility of GeNi 2 O 4 to a magnetic field swept from the direction of to via . Below the transition temperatures, the field dependence of the magnetization, M ( H ), reveals field-induced magnetic anisotropy.

We report on the crystallographic structure of the layered perovskite iridate Sr3Ir2O7, investigated using transmission electron microscopy. The space group was found to be Bbcb ( D 2 h 22 , No. 68 in the International Tables for Crystallography) at 315 K. A very fine twin structure with 90° rotation with respect to the c-axis was observed. The crystal structure at temperatures lower than 285 K, where a phase transition from paramagnetism to weak ferromagnetism is known to occur, was also examined. There was no difference in the extinction rule for the diffraction patterns between the two phases. We conclude that there is no change in the space group for this magnetic transition. There still remains the possibility of a change in the rotation angle of IrO6 octahedrons and a corresponding change in the interatomic distance between Ir and O, though.

We report a uniaxial pressure-dependence of magnetism in layered perovskite strontium ruthenate Sr3Ru2O7. By applying a relatively small uniaxial pressure, greater than 0.1 GPa normal to the RuO2 layer, ferromagnetic ordering manifests below 80 K from the enhanced-paramagnet. Magnetization at 1 kOe and 2 K becomes 100 times larger than that under ambient condition. Uniaxial pressure dependence of Curie temperature T_C suggests the first order magnetic transition. Origin of this uniaxial-pressure induced ferromagnetism is discussed in terms of the rotation of RuO6 octahedra within the RuO2 plane., 8 pages, 3 figures. to be published in Journal of the Physical Society of Japan, vol.73, No.5 (2004)

We report magnetic and transport properties of polycrystalline samples of bilayered perovskite Sr3Ir2O7, which is synthesized by using high pressure technique. Magnetic susceptibility shows weak ferromagnetism below 290K with small size of remanent moment (10−3μB/Ir). Resistivity shows insulating behavior below 290K. We discuss the magnetism and conductivity in Sr3Ir2O7 comparing with those of Sr3Ru2O7, which has a quite similar crystal structure to Sr3Ir2O7, from the view point of rotation angle of MO6 (M=Ir, Ru) octahedra.

The band structure for Sr2MoO4, which is isostructural with the unconventional spin-triplet superconductor Sr2RuO4, has been calculated within the local-density approximation. The results of the neutron-diffraction structure refinement used in the calculation are also presented. The elecronic structure of Sr2MoO4 resembles that of Sr2RuO4, while in Sr2MoO4 the anisotropy of Fermi velocity is considerably larger than that in Sr2RuO4. The neutron diffraction results and the structure optimization result suggest that the MoO6 octahedron is less elongated than the previously reported value.

To explore the possibility of the existences of superconductivity and ferromagnetism in Sr3Ru2O7, we have performed resistivity measurements on a single crystalline sample under uniaxial stresses of 0–110 MPa along the c-axis (perpendicular to the conducting RuO2 plane). In this stress region no superconductivity was so far detected down to at least 160 mK. At the same time an indication of ferromagnetism was not seen clearly in the resistivity, either. Technical difficulties yet to be overcome for further progress are discussed.

A case of spinal cord injury in a 16-year-old girl that was caused by stab wound is reported. She was admitted to the emergency department one day after being stabbed. When admitted she was conscious but was experiencing weakness in the lower limbs. The knife had penetrated through the left lamina to the right vertebral body at Th8. Treatment was conservative, and very good functional recovery was achieved.

We report a single-crystal growth technique for strontium ruthenates. Strontium ruthenates exhibit intriguing magnetic properties such as spin-triplet superconductivity in Sr 2 RuO 4 . To obtain pure single crystals of strontium ruthenates (Sr 2 RuO 4 , Sr 3 Ru 2 O 7 and SrRuO 3 ), we employed a conventional floating-zone method. For the crystal growth of Sr 2 RuO 4 , no severe difficulties are known. Even in air, it is possible to grow that single crystal from the molten zone of polycrystalline bar of Sr 2 RuO 4 . However, for Sr 3 Ru 2 O 7 and SrRuO 3 , it is impossible to obtain single crystals by the same procedure. We herein show the importance of oxygen-partial pressure in the atmosphere for the crystal growth of strontium ruthenates based on our successful results.

We have investigated the thermal expansion of the ferrimagnet FeSe of the hexagonal system by synchrotron radiation powder X-ray diffraction from room temperature down to 90 K. The lattice constants show anisotropic change against temperature. Especially, the c-axis expands down to 170 K, exhibiting negative linear thermal expansion. Almost the same behavior is found in the temperature dependence of the magnetization. This implies that the anomalous change of the c-axis has a strong correlation with magnetism. Magnetic fields up to 0.4 T do not affect the lattice constants at room temperature. Electrical resistivity indicates metallic behavior, i.e., there is a finite density of the state at the Fermi energy, consisting of the Fe3d and the Se4p states.

Aims/Introduction: Accumulation of intramyocellular lipid (IMCL) is associated with insulin resistance. However, the factors affecting the change in IMCL remain to be elucidated. The aim of the present study was to determine the factors that influence the change in IMCL level after high‐fat loading. Materials and Methods: The study subjects were 37 non‐obese men. Each subject consumed a high‐fat diet for 3 days after a normal‐fat diet for 3 days. After each diet program, IMCL levels in the tibialis anterior (TA‐IMCL) and soleus (SOL‐IMCL) were measured by proton magnetic resonance spectroscopy. Glucose infusion rate (GIR) was evaluated by euglycemic hyperinsulinemic clamp as an index of peripheral insulin sensitivity. Results: The high‐fat diet significantly increased TA‐IMCL and SOL‐IMCL by ∼30 and ∼20%, respectively (P

The concept of quantum criticality is proving to be central to attempts to understand the physics of strongly correlated electrons. Here, we argue that observations on the itinerant metamagnet Sr 3 Ru 2 O 7 represent good evidence for a new class of quantum critical point, arising when the critical end point terminating a line of first-order transitions is depressed toward zero temperature. This is of interest both in its own right and because of the convenience of having a quantum critical point for which the tuning parameter is the magnetic field. The relationship between the resultant critical fluctuations and novel behavior very near the critical field is discussed.

Two “superconducting transition temperatures” ( T c s) of Cu x Ba 2 Ca 3 Cu 4 O y were examined by the specific heat measurement. Comparing the specific heat under magnetic field (14 T) and that without field, two anomalies were observed in the electronic specific heat. When there are more than two Fermi surfaces (FSs) and the superconducting gaps do not develop simultaneously in these FSs, we can expect two anomalies. Strictly speaking the second anomaly at lower temperature ( T c2 ) is not due to the real phase transition but its vestige. A theoretical inspection indicates the second anomaly means the inter-FS interaction is very weak. If the symmetry of the superconducting gap on one FS is different from that on the other, one can expect a drastic suppression of the inter-FS interaction.

We report the results of low temperature transport, specific heat, and magnetization measurements on high quality single crystals of the bilayer perovskite ${\mathrm{Sr}}_{3}{\mathrm{Ru}}_{2}{\mathrm{O}}_{7}$, which is a close relative of the unconventional superconductor ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$. Metamagnetism is observed, and transport and thermodynamic evidence for associated critical fluctuations is presented. These relatively unusual fluctuations might be pictured as variations in the Fermi surface topography itself.

Specific heat anomaly was studied on Cu x Ba 2 Ca 3 Cu 4 O y . ΔC/ T c , a height of peak of the specific heat at the superconducting transition ( T c ) divided by T c , is less than 60% of that of optimally doped YBa 2 Cu 3 O 7-δ . This suggests that a large density of states (DOS) remains to prohibit the creation of Bardeen-Cooper-Schrieffer (BCS) pairs at T c . It is much larger than the residual DOS at 0 K. We interpret that the “ missing DOS ” start to become BCS pairs at a temperature lower than T c , as proposed by an NMR study [Phys. Rev. B 61 (2000) 9707], though we have not yet seen clear evidence of this.

It is said that early diagnosis is important in spinal infection, and MRI is useful for such diagnoses, because the disease often progresses rapidly, with late diagnosis leading to large epidural abscess and palsy.We report a 75-year-old man who had vertebral osteomyelitis (Th8-9) with diffuse epidural abscess compressing the Th6-9 region. Because he had dimentia, and was in a septic shock state, we managed only laminectomy and debridement by the posterior approach, after which irrigation was performed. The infection was difficult to control with antibiotics, and he died of multiple organ failure after six months.

We report on the superconductivity in FeSe samples, which were prepared from Fe and Se powder, synthesized by different sintering temperatures (Ts) from 573 K to 1173 K at intervals of 100 K. According to observation of the surface of the resulting samples using a scanning electron microscope (SEM), the grain-size increases from ∼1 μm (573 K) to ∼50 μm (1173 K) with raising Ts. These polycrystalline samples with Ts ⩾ 773 K, composed almost entirely of the tetragonal FeSe phase, although small amounts of the hexagonal FeSe phase were detected by X-ray diffraction (XRD) measurements. These samples indicated the negative susceptibility in magnetization, which gave estimates of the onset T c on ∼ 7 – 9 K , respectively. The sample for Ts = 873 K showed the maximum value of T c on .

The crystal structure of the ruthenate Sr{sub 3}Ru{sub 2}O{sub 7} as a function of temperature (5--305 K) and pressure (ambient -0.62 GPa) was studied by neutron diffraction. Upon cooling, the lattice parameter c and the rotation angle of the oxygen octahedra {phi} increase for 305K>T>50K, and decrease for 20K>T>5K. As pressure is applied at room temperature, the outer apical Ru-O bond expands. This remarkable behavior is discussed in terms of modification of the occupation of energy levels of the Ru{sup 4+} ion in the crystalline electric field of the oxygen octahedron and a crossover to Fermi-liquid behavior at low temperature. The very anisotropic thermal expansion leads, in sintered powder samples, to a high degree of strain, which is relieved somewhat with each cooling cycle.

We show that single-crystalline ${\mathrm{Sr}}_{3}{\mathrm{Ru}}_{2}{\mathrm{O}}_{7}$ grown by a floating-zone technique is an isotropic paramagnet and a quasi-two-dimensional metal, as spin-triplet superconducting ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ is. The ground state is a Fermi liquid with very low residual resistivity $(\ensuremath{\approx}3 \ensuremath{\mu}\ensuremath{\Omega}\mathrm{cm}$ for in-plane currents) and a nearly ferromagnetic metal with the largest Wilson ratio ${R}_{\mathrm{W}}g~10$ among paramagnets so far. This contrasts with the ferromagnetic order at ${T}_{\mathrm{c}}=104 \mathrm{K}$ reported on single crystals grown by a flux method [Cao et al., Phys. Rev. B 55, R672 (1997)]. However, we have found a dramatic changeover from paramagnetism to ferromagnetism under applied pressure. This suggests the existence of a substantial ferromagnetic instability in the Fermi-liquid state.

We present the phenomenological systematics of a series of ruthenates, (Ca, Sr) n +1 Ru n O 3 n +1 , which exhibits a rich variety of ground states. We will also discuss in some detail the physical properties of the two-dimensional Mott-transition system, Ca 2− x Sr x RuO 4 , in which the Mott insulator Ca 2 RuO 4 evolves into the spin-triplet superconductor Sr 2 RuO 4 by means of a band-width control.

We review recent NMR investigations on superconducting and magnetic properties in layered perovskite Sr 2 RuO 4 , isostructural to a high-T c cuprate. Measurements of the Knight shift and the nuclear spin-lattice relaxation rate 1/T 1 have identified its Cooper-pair spin state as a triplet and uncovered pronounced anisotropy in spin-fluctuation spectrum in Sr 2 RuO 4 The in-plane low-frequency components of the dynamical susceptibility are exchange-enhanced with a weak q dependence associated with the two-dimensional (2D) character in electronic structure. By contrast, its out-of-plane component is unexpectedly enhanced by AF spin fluctuations upon cooling below T * ∼130 K where the c-axis resistivity shows metallic behavior. We have found that the slightly-distorted cubic perovskite CaRuO 3 is a nearly ferromagnetic metal dominated by ferromagnetic spin fluctuations with a Stoner factor α=0.98. Contrasting behavior of spin fluctuations between Sr 2 RuO 4 and CaRuO 3 is due to their different dimensionality in electronic structure with the closeness to ferromagnetism. We remark that a simple ferromagnetic-spin-fluctuation-mediated mechanism with analogy to 3 He is not appropriate for an onset of spin-triplet p-wave superconductivity in Sr 2 RuO 4 . Altemately, we propose possible scenario that the in-plane local exchange interaction, which originates presumably from the Hund's coupling between the 4d and 4d xz,yz orbitals, may play a role for the occurrence of spin-triplet p-wave superconductivity.