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A gas temperature decay model in small air gaps after arc discharge has been developed, assuming that the recovering hot gas is a spherical lump. The calculation of the temperature decay by this model consists of the calculation of the time constants of the decay process. Time constants were determined as a function of the diameter of the spherical gas lump and the gas temperature, and were arranged to suit the actual geometrical shape of the arc channel which was measured by framing photographs. Temperature decay was calculated for different gap lengths between 1 and 7 mm and they showed a good agreement with those obtained from the experimental voltage recovery combined with the Paschen curve.

This paper proposes a distributed fault-tolerant algorithm for one-to-all broadcasting in the one-port communication model on the arrangement graph. Exploiting the hierarchical properties of the arrangement graph to constitute different-sized broadcasting trees for different-sized subgraphs, we propose a distributed algorithm with optimal time complexity and without message redundancy for one-to-all broadcasting in the one-port communication model for the fault-free arrangement graph. According to the property that there is a family of k(n − k) node-disjoint paths between any two nodes, we develop a fast fault-tolerant procedure capable of sending a message from a node to its adjacent nodes on the (n, k)-arrangement graph with less than k(n − k) faulty edges. Combining the fault-tolerant procedure and the optimal broadcasting algorithm, a fault-tolerant broadcasting is achieved on the arrangement graph. It is shown that a message can be broadcast to all the other (n!/(n − k)!) − 1 processors in O(k lg n) steps if no faults exist on the (n, k)-arrangement graph, and in O(k2 lg n + k lg2 n)) steps if the number of faulty edges is less than k(n − k). [ABSTRACT FROM AUTHOR]

The main motivation in undertaking this research was to address some of the practical issues that were widely reported during major disaster situations such as the 11 March, 2011 Tohoku earthquake in Japan. Apart from great loss of life and property in the near vicinity of the earthquake, metropolitan areas in Tokyo experienced disruption of train services, electrical outages and inaccessibility to Internet services leaving many commuters stranded. It is, therefore, necessary to develop a near real-time traversability mapping service that can be available during or soon after the disaster. In this research, we implemented a system that facilitates generation of updated road traversability map using aggregated GPS tracks. The post-processing consists of a line simplification based on Douglas-Peucker algorithm and map-matching with existing road network using Hausdorff distance algorithm. Line simplification was applied reduce the data in further processing and map-matching to remove outliers and generate a navigable traversability road network. Performance of map-matching algorithm, evaluated using data collected in two field campaigns in Yamate-cho, Suita City and Sumiyoshi-ward, Osaka City, Japan clearly demonstrates the efficacy of the proposed workflow. [ABSTRACT FROM AUTHOR]

Background: In patients with conjoined nerve roots, hemilaminectomy with sufficient exposure of the intervertebral foramen or lateral recess is required to prevent destabilization and ensure correct mobility of the lumbosacral spine. To the best of our knowledge, no case reports have detailed the long-term course of conjoined nerve roots after surgery., Case Presentation: We report the case of a 51-year-old Japanese man with a conjoined nerve root. The main symptoms were acute low back pain, radiating pain, and right leg muscle weakness. Partial laminectomy was performed with adequate exposure to the conjoined nerve root. The symptoms completely resolved immediately after surgery. However, the same symptoms recurred 7 years postoperatively. The nerve root was compressed because of foraminal stenosis resulting from L5-S disc degeneration. L5-S transforaminal lumbar interbody fusion was performed on the contralateral side because of an immobile conjoined nerve root. At 44 months after the second surgery, the patient had no low back pain or radiating pain, and the muscle weakness in the right leg had improved., Conclusions: This is the first report of the long-term course of conjoined nerve root after partial laminectomy. When foraminal stenosis occurs after partial laminectomy, transforaminal lumbar interbody fusion from the contralateral side may be required because of an immobile conjoined nerve root., (© 2024. The Author(s).)

Background: Intrathecal baclofen therapy can substantially improve symptoms in most patients with severe spasticity due to traumatic spinal cord injury, multiple sclerosis, or cerebral paresis. To the best of our knowledge, decompression surgeries at the intrathecal catheter insertion site in patients with a preexisting intrathecal pump for drug delivery have not been reported., Case Presentation: We report the case of a 61-year-old Japanese man with lumbar spinal stenosis who underwent intrathecal baclofen therapy. We performed decompression for lumbar spinal stenosis at the intrathecal catheter insertion site during intrathecal baclofen therapy. The yellow ligament was removed by partial resection of the lamina under a microscope to avoid damage to the intrathecal catheter. The dura mater was distended. No obvious cerebrospinal fluid leakage was observed. Postoperatively, lumbar spinal stenosis symptoms improved, and spasticity remained well controlled with intrathecal baclofen therapy., Conclusions: This is the first reported case of lumbar spinal stenosis decompression at an intrathecal catheter insertion site during intrathecal baclofen therapy. Preoperative preparation is necessary, as the intrathecal catheter may be replaced during surgery. We performed surgery without removing or replacing the intrathecal catheter, taking care not to damage the spinal cord by migrating the intrathecal catheter., (© 2023. The Author(s).)

Background: Simultaneous bilateral hip fractures without major trauma in the elderly are rare and usually symmetrical. To the best of our knowledge, only two cases of bilateral simultaneous asymmetric hip fracture in the elderly without major trauma have been reported., Case Presentation: We present the case of a 90-year-old Japanese man with simultaneous bilateral asymmetric hip fractures with trochanteric fracture on the right side and greater trochanteric fracture on the left side. He complained of dyspnea at midnight and was referred to our emergency department. He was admitted to the internal medicine department for bacterial pneumonia treatment. On the 8th day of hospitalization, he was referred to our orthopedic surgery department for hip pain and was found to have fractures of both hips. Computed tomography findings showed that the left femoral neck fracture was an old fracture, while the left greater trochanteric fracture and the right trochanteric fracture were fresh fractures. He was surgically treated through open reduction and internal fixation with an intramedullary nail on the right and hemiarthroplasty on the left in supine position, performed during the same surgical sessions on the 12th day of hospitalization., Conclusions: We report a new form of simultaneous bilateral asymmetric hip fracture in the elderly. The fracture types of the case were femoral trochanteric fracture and greater trochanteric fracture of the femur, which were different from the fracture types in the previously reported two cases. Clinicians should be aware of the possibility of simultaneous bilateral hip fractures, especially in the elderly., (© 2022. The Author(s).)

Background: Patients with tethered cord syndrome often suffer severe spasticity. To the best of our knowledge, intrathecal baclofen (ITB) therapy in a patient with tethered cord syndrome has not been reported previously. We describe a case in which ITB therapy was useful for treating severe spasticity in an adult with tethered cord syndrome., Case Presentation: We present the case of a 50-year-old Japanese woman with tethered cord syndrome and related conditions suffering from severe spasticity and pain in the lower limbs. She was born with a lumbosacral myelomeningocele, which was closed in the neonatal period. For 4-5 years before this presentation, spasticity in the lower limbs had been exacerbated without any obvious cause. She received rehabilitation and pharmacotherapy from a local doctor, but symptoms were unimproved, and her previous doctor referred her to this department. A test with 50 μg of intrathecally delivered baclofen showed total relief of spasticity and pain, so a pump was implanted for continuous baclofen delivery. During 24 months of follow-up, spasticity has remained under excellent control with baclofen at 38.5-41.0 μg/day., Conclusions: ITB therapy proved extremely effective in this adult with severe spasticity from tethered code syndrome., (© 2021. The Author(s).)

Background: Aspergillus terreus, a saprophytic fungus, is recognized as an emerging pathogen in various infections in humans. However, bone and joint involvement is uncommon. To the best of our knowledge, only seven cases of spondylodiscitis caused by Aspergillus terreus have been reported previously in humans. We report a case of a patient with Aspergillus terreus spondylodiscitis following an abdominal stab wound., Case Presentation: A 74-year-old Japanese man with no particular medical history fell from a ladder and sustained a left abdominal stab wound from an L-shaped metal peg. Computed tomography showed the trace of the L-shaped metal peg from the left abdomen to the left rib and left kidney. The scan also showed an anterolateral bone avulsion of the left side of the T12 vertebral body, as well as fractures of the L1 left transverse process and the left 10th-12th ribs. He was hospitalized and treated with conservative therapy for 6 weeks. He was readmitted to the hospital with complaints of sudden back pain, numbness of both legs, and inability to walk 13 weeks after the fall. Magnetic resonance imaging findings were typical of spondylodiscitis. Gadolinium-enhanced T1-weighted magnetic resonance imaging indicated increased signal intensity at T11-T12 vertebral bodies and severe cord compression and epidural abscess at T11-T12 associated with infiltration of soft paravertebral tissues. On the seventh day after admission, he underwent partial laminectomy at T11 and posterior fusion at T9 to L2. The result of his blood culture was negative, but Aspergillus terreus was isolated from the material of T11-T12 intervertebral disc and vertebral bodies. His Aspergillus antigen was positive in a blood examination. Histological examination showed chronic suppurative osteomyelitis. On the 35th day after admission, he underwent anterior fusion at T11 and T12 with a rib bone graft. For 5 months, voriconazole was administered, and he wore a rigid corset. Posterior partial laminectomy at T11 and anterior fusion at T11 and T12 resulted in a good clinical course. The patient's neurological dysfunction was completely recovered, and his back pain disappeared. Two years after the operation, computed tomography was performed and showed bone fusion at T11 and T12. Magnetic resonance imaging revealed no evidence of increased signal intensity at T11-T12 vertebral bodies and severe cord compression and epidural abscess at T11-T12., Conclusions: To our knowledge, this is the first report of spondylodiscitis caused by Aspergillus terreus after an abdominal penetrating injury. The histological finding of chronic suppurative osteomyelitis and the radiological findings strongly suggested direct inoculation of Aspergillus terreus.

Background: Although microendoscopy-assisted lumbar discectomy for lateral or extraforaminal lumbar disc herniations via the lateral approach has previously been reported, microendoscopy-assisted lumbar discectomy for central or paramedian disc herniations via the lateral approach has not been reported. We report the first case of recurrent upper lumbar disc herniation (L2-L3) treated with microendoscopy-assisted lumbar discectomy via the transforaminal approach. No microendoscopy-assisted lumbar discectomy for recurrent upper lumbar disc herniation via the transforaminal approach has previously been reported. Percutaneous endoscopic lumbar discectomy via the transforaminal approach is very useful as a minimally invasive surgery for disc herniations. We applied percutaneous endoscopic lumbar discectomy via the transforaminal approach, and invented a new microendoscopy-assisted lumbar discectomy via the transforaminal approach., Case Presentation: A 79-year-old Japanese man was operatively managed for recurrent L2-L3 herniation. An 18 mm skin incision was made approximately 70 mm from the midline to the lateral side to allow a sufficiently angled trajectory to the extraforaminal space. The transforaminal approach was used. The exiting nerve root was identified along its course inferior to the pedicle. The lateral portion of the pars interarticularis and the facet joint was removed using a high-speed drill under the guidance of an endoscope. The tip of the endoscope was set at the lateral side of the dura mater. The dura mater was retracted medially and gently, and the herniated disc fragments were removed safely. All symptoms were relieved postoperatively. Postoperative magnetic resonance imaging demonstrated disappearance of all herniated disc fragments. A postoperative three-dimensional computed tomographic scan demonstrated the complete preservation of the facet joint., Conclusions: This is the first report of a case of recurrent upper lumbar disc herniation treated with microendoscopy-assisted lumbar discectomy via the transforaminal approach. This procedure allows for the use of a nerve retractor and other instruments to detach adhesions from the dura mater. This procedure has the advantages of clear visualization of the dura mater, exiting nerve root, and traversing nerve root, and diminished risk of nerve injury, and complete preservation of the articular surface of the facet joint.

Background: A few reports have shown that the reliability of the Japanese Orthopaedic Association stage classification of hip osteoarthritis was not high. The objective of this study was to assess the reliability of the stage classification of coxarthrosis, and to evaluate whether a modification of the classification improves reliability., Materials and Methods: We retrospectively investigated 200 hips in 100 patients with hip pain. We collected radiographs of their hip joints with the patients in both a supine and a standing position. Four orthopaedic surgeons evaluated the stage of coxarthrosis employing the JOA classification. The percentage of agreement of examiners and the value of the kappa statistic were calculated. Furthermore, to improve the reliability of classification, we modified the classification based on previous reports. Partial narrowing of the joint space and disappearance of the joint space were defined as maintained if it was 2 mm or more, and as the width of the loss of joint space that was 10 mm or more respectively. Using this classification, the same examiners assessed the stage on the same radiographs again three months after the previous evaluation., Results: The percentages of agreement were 28.5% and 27% and the interobserver value of the kappa statistic was 0.45 and 0.44 in supine and standing position respectively. After modification of the classification, the percentages of agreement were 36.5% and 44% and the interobserver value of the kappa statistic was 0.48 and 0.56 in supine and standing positions respectively, and the intraobserver value of the kappa statistic was 0.55. The modification significantly improved the reliability only in the percentage of the agreement for the standing position., Conclusion: This study showed that the reliability of the JOA stage classification of coxarthrosis was not as high as previous reports have showed. Modification of the classification improved interobserver reliability., (Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Background: Diffuse idiopathic skeletal hyperostosis has long been regarded as a benign asymptomatic clinical entity with an innocuous clinical course. Neurological complications are rare in diffuse idiopathic skeletal hyperostosis. However, if they do occur, the consequences are often significant enough to warrant major neurosurgical intervention. Neurological complications occur when the pathological process of ossification in diffuse idiopathic skeletal hyperostosis extends to other vertebral ligaments, causing ossification of the posterior longitudinal ligaments and/or ossification of the ligamentum flavum. Thoracic spondylolisthesis with spinal cord compression in diffuse idiopathic skeletal hyperostosis has not previously been reported in the literature., Case Presentation: A 78-year-old Japanese man presented with a 6-month history of gait disturbance. A magnetic resonance imaging scan of his cervical and thoracic spine revealed anterior spondylolisthesis and severe cord compression at T3 to T4 and T10 to T11, as well as high signal intensity in a T2-weighted image at T10/11. Computed tomography revealed diffuse idiopathic skeletal hyperostosis at T4 to T10. He underwent partial laminectomy of T10 and posterior fusion of T9 to T12. The postoperative magnetic resonance imaging revealed resolution of the spinal cord compression and an improvement in the high signal intensity on the T2-weighted image., Conclusions: We report the first case of thoracic spondylolisthesis and spinal cord compression in diffuse idiopathic skeletal hyperostosis. Neurosurgical intervention resulted in a significant improvement of our patient's neurological symptoms.

Objective Stenotrophomonas maltophilia is an emerging nosocomial pathogen that causes fatal infections in critically ill or immunocompromised patients. S. maltophilia bacteremia (SMB) is a rare condition, and its clinical characteristics in Japanese settings are not well known. Methods The medical charts of patients with SMB were retrospectively reviewed at two medical facilities (Okayama University Hospital and Tsuyama Chuo Hospital) for seven years. The data were analyzed along with those previously reported from other Japanese facilities. Result A total of 181 patients (110 men and 71 women) were evaluated. The major underlying diseases included hematologic malignancy (36.5%), solid organ malignancy (25.4%), and neutropenia (31.5%). The recent use of carbapenem was seen in 56.9% of the cases in total, and more than one-third of the patients in our hospitals were treated with carbapenem at the onset of SMB. Of 28 (63.6%) of 44 cases treated for S. maltophilia, those who did not survive were more likely to have been treated with broad-spectrum antibiotics. A multivariate analysis revealed that a higher updated Charlson Comorbidity Index [odds ratio (95% confidence interval), 1.75 (1.11-2.75); p=0.015] and intubation [odds ratio (95% confidence interval), 12.6 (1.62-97.9); p=0.016] were associated with mortality in our cases. Pathogens were often resistant to ceftazidime but susceptible to minocycline, trimethoprim/sulfamethoxazole, and fluoroquinolones. The overall mortality rates within 30 and 90 days were 37.5% and 62.5%, respectively. Conclusion The clinical characteristics of SMB in Japanese cases were similar to those reported from other countries. Clinicians should be aware that breakthrough infection by S. maltophilia may occur during administration of carbapenem.

A 64-year-old man suffering polyarthralgia and bone pain was referred to our hospital. Renal dysfunction, hypophosphatemia and increased levels of bone alkaline phosphatase were found. The patient's serum creatinine level had gradually increased after the initiation of adefovir dipivoxil administration for hepatitis B. In agreement with multifocal uptakes of bone scintigraphy, iliac bone biopsy revealed an abnormal increase in osteoid tissues. Reducing the dose of adefovir and initiating the administration of eldecalcitol were effective for reducing proteinuria and glucosuria, and for ameliorating bone pain with an increase in serum phosphate level. This case first showed a clinical course of hypophosphatemic osteomalacia caused by secondary Fanconi's syndrome for 8 years after adefovir administration. Early diagnosis is important for the reversibility of bone damage and for a better renal prognosis.

We herein present the case of a 69-year-old Japanese man who had unprotected sexual contact with a local commercial sex worker in an East Asian country and was diagnosed as having disseminated gonococcal infection (DGI). The organism was confirmed to be Neisseria gonorrhoeae based on 16S rRNA sequencing and positive results for the cppB gene. This case indicates that a diagnosis of DGI should also be considered in elderly individuals. DGI potentially causes many complications, and the pathogen has recently been reported to be resistant to various antibiotics. Physicians must therefore pay more attention to the possible occurrence of DGI in various clinical settings.

A 27-year-old woman visited our hospital because of high fever. She had been diagnosed as 22q11.2 deletion syndrome (22q11.2DS) due to her cardiac history (tetralogy of Fallot), thymic hypoplasia and 22q11.2 deletion. She had a normal CD4/CD8 ratio, a slightly decreased lymphocyte count and normal serum immunoglobulin levels. Blood cultures were positive for Staphylococcus lugdunensis (S. lugdunensis). Infection route of S. lugdunensis in this case was unclear. The patient was successfully treated with several intravenous antibiotics. Infection should be considered when managing patients with 22q.11.2DS. regardless of whether their immune system is impaired.

A beam formed radiofrequency (RF) exposure-incubator employing a horn antenna, a dielectric lens, and a culture case in an anechoic chamber is developed for large scale in vitro studies. The combination of an open type RF exposure source and a culture case through which RF is transmitted realizes a uniform electric field (+/-1.5 dB) in a 300 x 300 mm area that accommodates 49 35 mm diameter culture dishes. This large culture dish area enables simultaneous RF exposure of a large number of cells or various cell lines. The RF exposure source operates at 2142.5 MHz corresponding to the middle frequency of the downlink band of the International Mobile Telecommunication 2000 (IMT-2000) cellular system. The dielectric lens, which has a gain of 7 dB, focuses RF energy in the direction of the culture case and provides a uniform electric field. The culture case is sealed and connected to the main unit for environmental control, located outside the anechoic chamber, via ducts. The temperature at the center of the tray, which contains the culture dishes in the culture room, is maintained at 37.0 +/- 0.2 degrees C by air circulation. In addition, the appropriate CO2 density and humidity supplied to the culture case realizes stable long-term culture conditions. Specific absorption rate (SAR) dosimetry is performed using an electric field measurement technique and the Finite Difference Time Domain (FDTD) calculation method. The results indicate that the mean SAR of the culture fluid at the bottom of the 49 (7 x 7 array) culture dishes used in the in vitro experiments is 0.175 W/kg for an antenna input power of 1 W and the standard deviation of the SAR distribution is 59%. When only 25 culture dishes (5 x 5 array) are evaluated, the mean SAR is 0.139 W/kg for the same antenna input power and the standard deviation of the SAR distribution is 47%. The proliferation of the H4 cell line in 72 h in a pair of RF exposure-incubators reveals that the culture conditions are equivalent to those of a common CO2 incubator., (2004 Wiley-Liss, Inc.)

Background: Mismatched distribution of pulmonary blood flow is a common characteristic in emphysematous patients. But few reports have mentioned the relationships between the morphological changes in the lungs as assessed by high-resolution computed tomography (HRCT), pulmonary blood flow (PBF) scan and the indices of exercise tolerance. We investigated these relationships., Objective: Pulmonary function tests (PFT), HRCT, single photon emission computed tomography ((99m)SPECT) and treadmill exercise tests were performed on emphysematous patients, and the correlations between these examinations were studied., Methods: We evaluated 20 patients (M 18, F 2, age 66 +/- 8.0 years). CT evaluation was performed according to the grade of emphysematous change. (99m)SPECT was performed to evaluate mismatched PBF by the score method. The better flow of the middle lobe was selected to be the standard lobe for the basic PBF. That score was set to 1 when the blood flow was below 60 or above 140%. PBF between 60 and 140% was scored as 0., Results: FEV(1 )(r = 0.648, p = 0.002) and VC (r = 0.767, p = 0.001) correlated significantly with Vdot;O(2) peak. FEV(1) (r = 0.667, p = 0.0018) correlated significantly with anaerobic threshold (AT). CT grade did not correlate with PBF mismatch score (r = 0.266, p = 0.3376). %Vdot;O(2 )peak did not correlate with CT grade (r = -0.467, p = 0.0689) or with mismatch PBF score (r = -0.327, p = 0.2377)., Conclusions: HRCT and (99m)SPECT were advantageous for detecting the progression of disease and emphysematous changes. However, the severity of anatomical emphysematous changes did not necessarily correlate with the indices of exercise tolerance and pulmonary function tests., (Copyright 2002 S. Karger AG, Basel)

The present study was designed to investigate a possibility of substitution of the venous blood radioactivity counts sampled 26 min post injection for the octanol-extracted arterial blood radioactivity counts obtained at 5 min after the injection of N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). Furthermore, we investigated whether the integral of input function can be estimated from the venous blood radioactivity counts sampled 26 min post injection and the whole-brain time-activity curves early after 123I-IMP injection. There was a good correlation between the arterial blood radioactivity counts sampled 5 min post injection (y) and those obtained at 26 min (r = 0.902; n = 91; y = 2.348x - 867.063). There was also a good correlation between the arterial (x) and venous blood radioactivity counts (y) sampled 26 min post injection (r = 0.954; n = 14; y = 0.761x + 924.336). The venous blood radioactivity counts sampled at 26 min (x) correlated well with the octanol-extracted arterial blood radioactivity counts sampled at 5 min (y) (r = 0.964; n = 32; y = 0.173x - 21.598). There was a good correlation between the integrals of input function obtained from the regression equation obtained above and the whole-brain time-activity curves acquired during 7 min post injection (y) and those obtained by 5-min continuous arterial blood sampling (x) (r = 0.965; n = 41; y = 0.957x + 2665.208). These results indicate that this noninvasive and simple method can estimate the integral of input function for quantification of cerebral blood flow using 123I-IMP.