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In this paper, consideration from the viewpoint of the dq-axis current vector locus is reported on the clues for improving the output of wound-field motor utilizing space harmonic for field excitation. It is experimentally verified by visualizing the vector locus on the dq coordinates. First, voltage equation will be explained, and then the offline parameter estimation will be discussed. Then, visualization of the voltage-limit ellipse and vector locus will reveal clues for performance improvement.

Double crush syndrome (DCS) is a clinical condition involving impingement of the spinal and peripheral nerves. DCS of the lower limbs has been recognized; however, no detailed reports have been published. Herein, we report a rare case of the coexistence of L5 radiculopathy and peroneal nerve entrapment neuropathy. The patient suffered from pain in the left lower leg and left foot combined with muscle weakness in the left leg without a Tinel-like sign in the peroneal tunnel area. MRI showed a deficit in the left L5 nerve root sleeve, and X-ray imaging revealed L5 spondylolysis. Lumbar fusion surgery was performed at L5-S1. Subsequently, the patient’s symptoms were partially improved, but the pain and toe and ankle motor weakness persisted. In addition, a Tinel-like sign appeared at the entrapment point of the peroneal nerve. The entrapped peroneal nerve was decompressed, and the patient’s symptoms improved. The patient had L5 radiculopathy owing to the improvement in his symptoms in the upper leg before and after lumbar surgery. It is unclear why no Tinel-like sign was detected before the first surgery, but we hypothesized that L5 nerve disorder may mask the symptoms triggered by compression of the peroneal nerve due to the complex pathology of DCS and dynamic factors. Distinguishing between radiculopathy and relative peripheral neuropathy should always be a consideration. DCS may mask characteristic symptoms, and it is important to carefully follow up the patient to detect changes in his or her condition.

Chronic subdural hematoma (CSDH) is considered to be an inflammatory and angiogenic disease. The CSDH outer membrane, which contains inflammatory cells, plays an important role in CSDH development. Osteopontin (OPN) is an extracellular matrix protein that is cleaved by thrombin, generating the N-terminal half of OPN, which is prominently involved in integrin signal transduction. We explored the expression of the N-terminal half of OPN in CSDH fluid and the expression of integrins α9 and β1 and the downstream components of the angiogenic signaling pathways in the outer membrane of CSDHs. Twenty samples of CSDH fluid and 8 samples of CSDH outer membrane were included. The concentrations of the N-terminal half of OPN in CSDH fluid samples were measured using ELISA kits. The expression levels of integrins α9 and β1, vinculin, talin-1, focal adhesion kinase (FAK), paxillin, α-actin, Src and β-actin were examined by western blot analysis. The expression levels of integrins α9 and β1, FAK and paxillin were also examined by immunohistochemistry. We investigated whether CSDH fluid could activate FAK in cultured endothelial cells in vitro. The concentration of the N-terminal half of OPN in CSDH fluid was significantly higher than that in the serum. Western blot analysis confirmed the presence of these molecules. In addition, integrins α9 and β1, FAK and paxillin were localized in the endothelial cells of vessels within the CSDH outer membrane. FAK was significantly phosphorylated immediately after treatment with CSDH fluid. Our data suggest that the N-terminal half of OPN in CSDH fluid promotes neovascularization in endothelial cells through integrins α9 and β1. The N-terminal half of OPN, which is part of the extracellular matrix, plays a critical role in the promotion of CSDH.

This study clarifies experimentally the effect of the secondary conductor bar on line-start characteristics in a line-start type self-excited wound-field synchronous motor. This motor is based on a brushless wound-field synchronous motor having a rotor winding connected to a diode rectifier circuit. And it has a secondary conductor bar that is independently connected at a pitch of one pole, without end-ring. First, the operation principle of the proposed motor and its magnetic circuit design are described, and then the details of the prototype for principle verification are clarified. Next, when the combination of the connecting of the secondary conductor bar is changed, an experiment of line-starting characteristics and measured rotor field current is demonstrated. Consequently, it was clarified that the influence on the synchronous pull-in, speed ripple, and rotor field current.

This paper describes a novel line-start type self-excited wound-field synchronous motor with three-phase concentrated winding stator. The unique feature of this proposed motor is that it accelerates by obtaining the induction torque from the slip frequency at the time of starting, and at the time of synchronous pull-in, it is driven synchronously with the second order space harmonic as the field magnetization power. First, the operation principle and the magnetic circuit design topologies will be described. Then, the prototype for principle verification and experimental setup will be revealed. Next, the result of evaluating the no-load synchronization pull-in characteristics in actual machine evaluation is reported.

This article describes a novel line-start type self-excited wound-field synchronous motor with three-phase concentrated winding stator. The unique feature of this proposed motor is that it accelerates by obtaining the starting torque from the slip frequency at the time of starting, and at the time of synchronous pull-in, it is driven synchronously with utilizing the second order space harmonic as the field magnetization power. This driving principle was verified by performing a load test using the prototype with two types of load, fan load and eddy current brake load. Consequently, the synchronization based on the proposed drive principle could be demonstrated on the actual machine, and the line-start characteristics of the proposed motor have been clarified.

Chronic subdural hematoma (CSDH) is considered to be an inflammatory and angiogenic disease. Osteopontin is an extracellular matrix protein. Osteopontin is cleaved by thrombin, resulting in N-half osteopontin, which is more prominent in integrin signal transduction. We examined the expression of N-half osteopontin in the CSDH fluid and the expression of integrin α9 and β1 and the downstream components of the angiogenic signaling pathways in the outer membrane of CSDHs. Twenty samples of CSDH fluid and 8 samples of CSDH outer membrane were included. The concentrations of N-half osteopontin in the CSDH fluid were measured using ELISA kits. The expression of integrin α9 and β1, vinculin, talin-1, focal adhesion kinase (FAK), paxillin, α-actin, Src and β-actin was examined by western blot analysis. The expression of integrin α9 and β1, FAK and paxillin was also examined by immunohistochemistry. We investigated whether CSDH fluid could activate FAK in cultured endothelial cells in vitro. The concentration of N-half osteopontin in CSDH fluid was significantly higher than that in the serum. Western blot analysis revealed above-mentioned molecules. In addition, integrin α9 and β1, FAK and paxillin were localized in the endothelial cells of vessels within the CSDH outer membrane. FAK was significantly phosphorylated immediately after treatment with CSDH fluid. Our data suggest that N-half osteopontin in CSDH fluid promotes neovascularization in endothelial cells through integrins α9 and β1. The N-half osteopontin and integrin signaling pathway might be a useful therapeutic target for treating the growth of refractory CSDH.

Background Spinal epidural hematoma associated with epidural metastasis is very rare. Epidural hematoma is unusual in itself, and metastatic epidural tumors do not commonly occur. Case Description A 76-year-old man with a medical history of untreated stage III rectal cancer and chronic obstructive pulmonary disease underwent emergency spine surgery for acute development of severe quadriplegia due to cervical epidural hematoma after minor indirect trauma. Hemorrhagic lesions, such as yellow ligaments, were accompanied by hematomas that adhered to the dura mater and were confirmed on pathology to be small cell carcinoma. Some nodules were detected in the right pulmonary hilar lesion and pleural lesion on computed tomography, and stage IV small cell carcinoma was diagnosed. Conclusions To our knowledge, spinal epidural hematoma accompanied by epidural metastasis has not previously been reported. We hypothesized that tissue invasion of malignant neoplasms may cause hemorrhagic conditions. The presence of a tumor should therefore be considered in the differential diagnosis of cases of epidural hematoma.

This paper describes the conductor eddy current loss that occurs in a permanent magnet type synchronous motor with a distributed winding stator using a rectangular copper wire designed for mild hybrid system applications for small vehicles. Compared with the conventional round wire inserter method, the space factor can be improved and the coil-end length can be shortened by applying a so-called hairpin windings using a pre-formed into hairpin shape of bar conductor, and as a result, DC current resistance of the armature winding can be reduced. However, since the conductor cross-sectional area tends to increases, the conductor eddy current loss generated by the space harmonics linkage becomes too large to ignore. In order to study the reduction of the conductor eddy current loss, it is important to visualize the spatial leakage flux distribution which causes loss and finely analyze how the magnetic path is formed. Therefore, analysis of the conductor eddy current loss distribution generated in the bar-wound conductor is performed using the CAE model that faithfully reproduces the coil-end shape of the actual machine. Furthermore, it was qualitatively clarified what ratio of conductor eddy current loss at various driving points. Finally, the results of preliminary study on reduction of conductor eddy current loss are reported.

Objective The purpose of this study was to determine the sensitivity and specificity of using the spinal midline (M line) on a radiographic anteroposterior (AP) view for detecting pedicle screws (PSs) breaching the medial pedicle wall. Methods We retrospectively reviewed 145 patients who underwent fusion surgery using PSs between January 2006 and May 2017. We defined the M line as a line that connected the upper and lower spinous processes through the fixed vertebrae. The M line was positive if the tip of the PS crossed the M line. The reference standard was a computed tomography scan. The reliability of the M line was examined. Results The subjects included 145 patients (70 men and 75 women; mean age, 63.4 years). A total of 599 PSs were examined. Most cases were because of spondylolisthesis (66.9%). Most screws were inserted at a lower lumber level (77.6%). Analysis of the diagnostic accuracy of the M line yielded a sensitivity of 74.1% and a specificity of 95.3%. In addition, the positive predictive value of the M line was 42.6%, and the negative predictive value of the M line was 98.7%. Conclusions Assessment of the M line via an intraoperative radiographic AP view is a simple, readily available, complementary method for detecting PSs that have breached the medial pedicle wall in the thoracic, lumbar, and sacral spine. In particular, the M line has a strong negative predictive value, which is much more meaningful.

Chronic subdural hematoma (CSDH) is fundamentally treatable, although it sometimes recurs. We observed, however, several cases of spontaneous resolution of CSDH outer membranes, even in a trabecular type of CSDH, after a trepanation surgical procedure. In this study, we examined the expression of molecules of the autophagy signaling pathway in CSDH outer membranes. Eight patients whose outer membranes were obtained successfully during trepanation were included in this study. By Western blot analysis, we examined the expression of mammalian target of rapamycin (mTOR); GβL; UNC-51-like kinase-1 (ULK1); Beclin-1; autophagy-related genes (Atg) 3, 5, 7, 12, 13, and 16L1β,α; the autophagy marker Light Chain3A/B (LC3A/B); and β-actin, which constitute the autophagy signaling pathway. The expression levels of Beclin-1, Atg12, and LC3A/B were also examined by immunohistochemistry. Almost all of these molecules could be detected in all samples. Beclin-1, Atg12, and LC3A/B were found to be localized in the endothelial cells of vessels and fibroblasts in CSDH. We detected molecules of the autophagy signaling pathway in CSDH outer membranes. Autophagy contributes to the tissue homeostatic process, maintaining cellular integrity by clearing debris. Our data suggest that autophagy might play an important role in the spontaneous resolution of CSDH. Therefore, these molecules may be novel therapeutic targets for the treatment of those with CSDH.

Eosinophils induce inflammation by releasing cytokines and cytotoxic granule proteins. Infiltration of eosinophilic granulocytes occurs in the outer membrane of chronic subdural hematomas (CSDHs). Eosinophils play an important role in the growth of CSDHs. However, the manner in which eosinophils accumulate within CSDH fluid remains undetermined. In the current study, we assessed the expression of eosinophil chemoattractants in CSDH fluids according to growth stage of CSDHs and examined the correlation between the two. CSDH fluids were obtained from 38 patients during trepanation surgery. Ecalectin, eotaxin-3, interleukin-5 (IL-5), and eosinophil-derived neurotoxin (EDN) concentrations were measured using enzyme-linked immunosorbent assay kits. For use as controls, serum samples were collected from 5 healthy adults, and cerebrospinal fluid (CSF) samples were collected from 5 adults with unruptured aneurysms. The percentage of eosinophils (%eosinophil) in CSDH fluids was calculated using Giemsa staining. Concentrations of ecalectin, eotaxin-3, IL-5, and EDN were nearly equivalent in serum and CSF samples; however, their concentrations were high in CSDH fluids. In particular, ecalectin and EDN levels in CSDH fluids were significantly higher than those in serum and CSF. Levels of eotaxin-3, IL-5, EDN, and %eosinophil were significantly higher in laminar type of CSDH, whereas that of ecalectin was not. The correlations between eotaxin-3 and IL-5, IL-5 and EDN, and EDN and %eosinophil were statistically significant (p 0.01). Our data suggest that eotaxin-3 is a chemoattractant of eosinophils. IL-5 induces the activation of eosinophils subsequent to degranulation of EDN into CSDH fluids. These factors may serve as novel therapeutic targets for managing CSDH.

OBJECTIVEThe posterior inferior cerebellar artery (PICA) and the vertebral artery (VA) often exhibit anatomical variations at the craniovertebral junction (CVJ). An example of this is the PICA originating extradurally from the V3 segment of the VA. To date, some cadaveric investigations have been reported, but the incidence and relationship of this variation to the VA and the atlas as observed on clinical imaging have not been discussed. This study evaluated the prevalence of PICAs originating from the V3 on CT scanning. Other variations of the atlas and VA were also analyzed.METHODSCT images from a series of 153 patients who underwent 3D CT angiography (CTA) were analyzed, and variations of the PICA, VA, and atlas were investigated.RESULTSA total of 142 patients (284 sides) were analyzed; 11 patients (7.2%) were excluded due to poor image quality. The most common VA variation was the PICA originating from V3 (9.5% of 284 sides), which was more frequently observed on the nondominant VA than the dominant VA (22.5% vs 6.25%, p = 0.0005). A VA with a PICA end was identified in 4 sides (1.4%), which is the same incidence as observed in the persistent first intersegmental VA (1.4%). VA fenestration was only found in 1 side (0.35%). Regarding the atlas, ponticulus posticus was observed in 24 sides (8.5%). There was no relationship between the incidence of ponticulus posticus and the variations of the VA.CONCLUSIONSA PICA originating from V3 was the most common VA variation at the CVJ and was more common on the nondominant VA. Three-dimensional CTA is useful for the evaluation of this variance. Surgeons should be mindful of this variation during operations.

This study proposes a permanent-magnet (PM)-free magnetic-modulated motor where the magnetic flux variation in a differential frequency between the armature fundamental rotating magnetic field frequency and the rotor rotation speed frequency is effectively utilised for the field magnetisation instead of PMs. The operation principle of the self-excitation with a diode rectifier circuit on the rotor is discussed. Magnetic circuit design and structural design of downsized prototype machine are performed for the purpose of experimental verifications of self-excitation. In addition, the preliminary experimental test results are demonstrated with prototype machine. Consequently, it is confirmed that the proposed PM-free magnetic-modulated motor can automatically obtain the field magnetisation power by utilising differential frequency which is inevitably generated by magnetic-modulation technique.

We previously demonstrated that the inflammatory cytokine interleukin-6 (IL-6) activates the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling pathway in fibroblasts within the outer membranes of chronic subdural hematomas (CSDHs), and the activation of this pathway may induce CSDH outer membrane growth. The inhibitory system for this signal transduction pathway is unknown. CSDH fluids were obtained from 10 patients during trepanation surgery as the case group, and cerebrospinal fluid (CSF) samples were obtained from seven patients suffering from subarachnoid hemorrhage (SAH) on Day 1 as the control group. The concentrations of IL-6, soluble IL-6 receptor (sIL-6R), and soluble gp130 (sgp130) in CSDH fluid and CSF were measured using enzyme immunoassay kits. The co-localization of IL-6 and sgp130 in CSDH fluid was examined by immunoprecipitation. The expression levels of STAT3, JAK2, suppressor of cytokine signaling 3 (SOCS3), and protein inhibitor of activated Stat3 (PIAS3) in the outer membranes of CSDHs were examined by immunostaining. Soluble IL-6R and sgp130 concentrations in CSDH fluid were significantly higher than those in CSF after SAH. Sgp130 and IL-6 were co-immunoprecipitated from CSDH fluid. Immunostaining revealed STAT3, JAK2, SOCS3, and PIAS3 expression in fibroblasts located in the outer membranes of CSDHs. Soluble gp130 binds to IL-6/sIL-6R and acts as an antagonist of the JAK/STAT signaling pathway. SOCS3 also binds to JAK and inhibits its signaling pathway. In addition, PIAS3 regulates STAT3 activation. These factors might down-regulate the IL-6/JAK/STAT signaling pathway in fibroblasts within CSDH outer membranes. Therefore, these molecules may be novel therapeutic targets for the inhibition of CSDH growth.

This paper describes a novel self-excitation technique in which space harmonics and carrier harmonic is effectively utilized for the field magnetization instead of permanent magnets. The unique point of this technique are the following points. The second-order space harmonic that is structurally unavoidably generated in the motor with concentrated winding stator is utilized for self-excitation by inductive coupling. Secondary, the carrier harmonics inevitably generated in motor controlled by inverter are utilized for flux-intensifying by inductive resonance coupling. After explaining the proposed new self-excitation principle, then, the prediction of driving characteristics by electromagnetic field analysis (FEA) is shown. In particular, the effect of value of the carrier frequency to be magnetically resonant coupled and the torque improvement effect by the flux-intensified electromagnet are clarified. Consequently, it has been clarified that the proposed new permanent- magnet free motor can improve the torque density in the low-speed area because the carrier harmonic can generates the large electromangetomotive force in rotor winding by inductive resonance coupling.

An adjustable field magnetic flux permanent magnet (PM) motor is proposed in this paper, which is based on a permeability modulation technique. The proposed PM motor has magnetic paths made of soft magnetic metal between the permanent magnet poles in the rotor, and a special coil for the permeability modulation of the soft magnetic metal. The proposed PM motor can control the amount of the leakage flux between the rotor permanent magnet poles by means of magnetic saturation of the soft magnetic metal, where the main magnetic flux interlinking to the stator windings is effectively reduced because the leakage flux between the permanent magnet poles is dominant. However, when the soft magnetic metal is magnetically saturated by the zero-phase magnetic flux, the leakage magnetic flux is reduced, resulting in the enhancement of the main magnetic flux to the stator. This paper demonstrates computer simulation results of the proposed strategy for the adjustable field magnetic flux PM motor.

Objective The resection of foramen magnum meningiomas (FMMs) presents neurosurgical challenges. We propose a simple classification of the tumor location and the operating space created by the tumor to help treatment planning. Methods We retrospectively analyzed 16 FMMs and divided them into 3 groups based on the tumor location—clival, foraminal, and atlantal tumors. The distance between the condyle and the neuraxis at the level of the foramen magnum was measured and defined as the available operative space (AOS). We also reviewed intraoperative video recordings to assess the surgical exposure of the tumor by the space created by the FMM and compared it with the AOS. Results There were 4 clival, 8 foraminal, and 4 atlantal tumors. The AOS of the clival tumors was 10 mm ± 1.7, the AOS of the foraminal tumors was 18 mm ± 3.7, and the AOS of the atlantal tumors was 12 mm ± 2.1. All foraminal and atlantal tumors could be detached without a brain retractor. Because a major portion of the clival tumors was covered by the spinomedullary junction, a brain spatula was needed to obtain the required surgical space. The difference in AOS between clival and foraminal/atlantal tumors was statistically significant (P = 0.044). Although 4 patients experienced postoperative complications, the average postoperative Karnofsky performance scale score improved. The surgical complication rate was significantly lower in foraminal and atlantal FMMs than in clival FMMs (P = 0.027). Conclusions The simple classification of the tumor location helped to assess surgical difficulties. Knowledge of the space created by the FMMs between the condyle and the neuraxis is useful for planning the approach strategy, especially for estimating the available working space without resection of the occipital condyle.

This paper describes a novel squirrel cage type induction machine utilizing space harmonics for brushless secondary excitation. The unique point of this proposed technique is able to utilize space harmonic for additional torque generation. Its space harmonic is inevitably generated by concentrated winding structure. The magnetic circuit topology of brushless secondary excitation technique with space harmonic and its effects on torque increase is conducted by FE-analysis. Then, the driving performance are analytically revealed by comparing with conventional squirrel cage type induction machine.

To estimate the iron loss with higher harmonics accurately, the method based on the finite element analysis is proposed. The accuracy of the conventional methods based on the empirical approach deteriorates at the high frequencies and in the case with the minor loops, because they rely on the material measurement that differs from the actual operating conditions. The proposed method can calculate the hysteresis losses with the minor loops accurately using the Play-Hysteron model. It can estimate the “classical” eddy current losses at higher frequencies using the 1D method. Regarding the “anomalous” eddy current loss, “dynamic” anomalous loss factor is introduced in this research. The iron losses due to the minor loops of the lamination steel sheets are measured and compared with the simulation result using the Play-Hysteron model and the 1D method. The iron losses are also measured under the conditions considering the effect of the slot harmonics and PWM carrier harmonics. The proposed method reproduces well the measurement.

This paper describes a study of large-scale electromagnetic field analysis on super-computer (K-computer in Japan) in order to analyze the conductor eddy current loss of the interior permanent magnet synchronous motor using a bar-wound conductor in detail. In order to analyze the conductor eddy current loss due to the leakage magnetic flux at the typical driving point in detail, the same coil forming state as the actual prototype was modeled on the CAE and electromagnetic field analysis was performed. Furthermore, the preliminary study to reduce the conductor eddy current loss was accomplished.