A shunt active filter based on voltage detection for harmonic termination of a radial power distribution line

This paper focuses on a shunt active filter based on the detection of harmonic voltages at the point of installation. The objective of the active filter is to attenuate harmonic propagation resulting from series/parallel resonance between capacitors for power factor correction and line inductors in a power distribution line. The active filter acts as a low resistor to the external circuit for harmonic frequencies, and it is installed on the end bus of the power distribution line, just like a 50 &#937; terminator installed on the end terminal of a signal transmission line. Therefore, the function of the active filter is referred to as “harmonic termination” in this paper. Experimental results obtained from a laboratory system rated at 200 V and 20 kW verify that the active filter for the purpose of harmonic termination has the capability of harmonic damping throughout the power distribution line</p

Mutual Inductance Measurement for Power Device Package Using Time Domain Reflectometry

Stray inductance inside power device package will be a constraint on improvement of power density as well as switching frequency in power converters because the converters will suffer from electromagnetic interference (EMI)-related problems. This paper proposes a measurement method of mutual inductance for power device packages using time domain reflectometry. The method is characterized by introducing four-terminal measurement that distinguishes self and mutual inductances among collector, emitter, and gate terminals. A measurement fixture for a discrete IGBT is designed, constructed, and tested to ensure repeatability of the proposed method. Experimental results verifies the viability of the proposed method.2016 IEEE Energy Conversion Congress and Exposition (ECCE), 18-22 September 2016, Milwaukee, WI, US

α-Synuclein Transgenic Drosophila As a Model of Parkinson's Disease and Related Synucleinopathies

α-Synuclein (α-Syn) is a major component of protein inclusions known as Lewy bodies, which are hallmarks of synucleinopathies such as Parkinson's disease (PD). The α-Syn gene is one of the familial PD-causing genes and is also associated with an increased risk of sporadic PD. Numerous studies using α-Syn expressing transgenic animals have indicated that α-Syn plays a critical role in the common pathogenesis of synucleinopathies. Drosophila melanogaster has several advantages for modeling human neurodegenerative diseases and is widely used for studying their pathomechanisms and therapies. In fact, Drosophila models expressing α-Syn have already been established and proven to replicate several features of human PD. In this paper, we review the current research on synucleinopathies using α-Syn Drosophila models and, moreover, explore the possibilities of these models for comprehensive genetic analyses and large-scale drug screening towards elucidating the molecular pathogenesis and developing therapies for synucleinopathies

Surgical Treatment for Atlanto-Occipital Subluxation due to Destructive Spondyloarthropathy in a Patient Undergoing Long-Term Hemodialysis

Destructive spondyloarthropathy (DSA) has been reported in patients undergoing long-term hemodialysis. Cervical spinal lesions, including those of the upper cervical spine, are reported to be some of the most common. To our knowledge, we report for the first time, a case of atlanto-occipital subluxation requiring surgical treatment due to severe myelopathy and nuchal pain in a patient undergoing long-term hemodialysis. The patient was a 66-year-old woman who had undergone hemodialysis for 40 years. She visited our hospital due to an acute progression of gait disturbance and severe nuchal pain. Computed tomography showed posterior subluxation of the atlanto-occipital joints. DSA was also observed in the lower cervical spine. Magnetic resonance imaging showed spinal canal stenosis at both the upper and lower cervical levels. We performed Oc-C7 fixation, C1 laminectomy, and C3-C7 laminoplasty. We first recognized that the atlanto-occipital subluxation was caused by the extremely long-term, in this case, 40 years, hemodialysis

Surgical Outcome for Hemodialysis-Related Upper Cervical Lesions

Study DesignA retrospective study.PurposeTo investigate the surgical outcome for hemodialysis-related upper cervical lesions.Overview of LiteratureSurgical outcome of lower cervical lesions in patients undergoing hemodialysis has been reported. However, surgical outcome for upper cervical lesions in hemodialysis patients is unclear.MethodsUpper cervical lesions in nine patients undergoing hemodialysis were surgically treated. Mean age at surgery was 61.6 years (range, 52-68 years), and the mean follow-up period was 45.4 months (range, 2-98 months). Patients had undergone hemodialysis for an average of 25.3 years (range, 16-40 years) at surgery. Seven patients with destructive spondyloarthropathy (DSA) of the upper cervical spine were treated with atlantoaxial or occipitocervical fixation. Two patients with retro-odontoid pseudotumors were treated with C1 posterior arch resection alone. Japanese Orthopedic Association (JOA) scores for cervical myelopathy, postoperative complications, postoperative radiography, and preoperative and postoperative occipital pain were evaluated.ResultsMean preoperative and postoperative JOA score was 3.7 and 8.1, respectively. The seven patients with DSA had severe preoperative occipital pain that disappeared postoperatively. Postoperative radiography showed solid bone union in DSA cases and no instability in pseudotumor cases.ConclusionsSatisfactory surgical outcome was observed for hemodialysis-related upper cervical lesions

Differential Diagnosis of Tumoral Lesions in the Spinal Canal in Patients Undergoing Hemodialysis

Study DesignA retrospective study.PurposeTo clarify the features useful for the differential diagnosis of spinal canal tumoral lesions in patients undergoing hemodialysis.Overview of LiteratureTumoral lesions in the spinal canal are rarely found in hemodialysis patients. Therefore, the differential diagnosis of tumoral lesions in the spinal canal in hemodialysis patients has been very difficult.MethodsSpinal canal tumors in 17 patients undergoing hemodialysis or continuous ambulatory peritoneal dialysis were investigated. Histopathological analysis was conducted for all specimens obtained during surgery. The tumoral lesions were categorized into 3 groups on the basis of histopathology: spinal cord tumor, amyloidoma, and other. Patient medical history and diagnostic images of each group were reviewed.ResultsEight of 17 cases were histopathologically diagnosed as spinal cord tumors and were neurinomas, 6 were amyloidomas, and 3 were classified as other. The rate of spinal cord tumors was 47.1% (8 of 17 cases), which revealed the most frequent lesion type. The rate of amyloidomas and other types was 35.3% (6 of 17 cases) and 17.6% (3 of 17cases), respectively. In the amyloidoma group, the mean duration of hemodialysis (24.3 years) was longer than that of spinal cord tumors and other types (9.2 years and 8.6 years, respectively). All spinal cord tumors were intradural extramedullary, whereas all amyloidomas and other types were extradural.ConclusionsThe rate of each tumoral lesion, the duration of hemodialysis, and the tumoral localization are important features for the differential diagnosis of tumoral lesions in the spinal canal in hemodialysis patients

Pycnodysostosis with Multi-Segmental Spinal Canal Stenosis due to Ossification of the Yellow Ligament

Pycnodysostosis is an autosomal recessive disorder characterized by osteosclerosis, small stature, acro-osteolysis of the distal phalanges, loss of the mandibular angle, separated cranial sutures with open fontanels, and frequent fractures. One identified cause of the disease is reduced activity of the cysteine protease cathepsin K. A 48-year-old woman with a history of frequent fractures presented with a severe gait disturbance. Radiography, computed tomography, magnetic resonance imaging, and gene analysis were performed. Physical examination revealed open fontanels, and radiographs showed increased bone density. DNA sequence analysis revealed a deletion mutation of the cathepsin K gene. We diagnosed pycnodysostosis based on these findings. The magnetic resonance and computed tomography images demonstrated multilevel spinal canal stenosis due to ossification of the yellow ligament. We performed a laminectomy, and the patient's neurological signs and symptoms improved. To our knowledge, this is the first case of pycnodysostosis with ossification of the yellow ligament