Search

The high design luminosity of the SuperKEKB electron-positron collider will result in challenging levels of beam-induced backgro\ unds in the interaction region. Understanding and mitigating these backgrounds is critical to the success of the Belle~II experi\ ment. We report on the first background measurements performed after roll-in of the Belle II detector, a period known as SuperKE\ KB Phase 2, utilizing both the BEAST II system of dedicated background detectors and the Belle II detector itself. We also repor\ t on first revisions to the background simulation made in response to our findings. Backgrounds measured include contributions f\ rom synchrotron radiation, beam-gas, Touschek, and injection backgrounds. At the end of Phase 2, single-beam backgrounds origina\ ting from the 4 GeV positron Low Energy Ring (LER) agree reasonably well with simulation, while backgrounds from the 7 GeV elect\ ron High Energy Ring (HER) are approximately one order of magnitude higher than simulation. We extrapolate these backgrounds for\ ward and conclude it is safe to install the Belle II vertex detector., Comment: 22 Pages, 33 figures

ΔΕΝ ΔΙΑΤΙΘΕΤΑΙ ΠΕΡΙΛΗΨΗ, Instructive information on the treatment for chronic deep infections of digital joints in a 9-month-old Holstein heifer is described in this report. Preoperative ultrasonographic and radiographic examinations revealed soft tissue swelling and subchondral bone lysis at the distal part of the proximal phalanx in the lateral digit. Arthrectomy was performed under xylazine sedation to remove infectious articular cartilage tissues. Immature callus formation was observed via radiography at the surgical site by the 28th postoperative day. On the 48th postoperative day, callus fellinto disrepair on the radiographs along with aggravation of the locomotion score. After the application of a half-limb cast, the immature callus formed again by the 62nd postoperative day (11 months), and bony callus formation was observed by the 74th postoperative day. Thereafter, the heifer could walk well with marked improvement in the locomotion score. The withers height of the heifer at 13 months (136 cm) was within the range of that in control heifers of the same age on this farm (133 ± 3 cm); however, the body weight (BW) of this heifer (322 kg) was lower than the BW of controls (384 ± 26 kg). The BW gain from 11 to 13 months of age seemed to be higher in the present heifer (+76 kg) than in controls (+55±20 kg), suggesting that BW of the present heifer was returning to the original BW. Based on these observations, we suggested that arthrectomy was an effective treatment option for the present case of digital joint arthritis.

The front-end electronics system for the Belle II Time-Of-Propagation (TOP) counter was fully installed in May 2016. The detector is a novel particle identification device for the barrel region, where Cherenkov ring images are reconstructed with precise timing information of each photon. The readout electronics need to have excellent timing performance for single photon detection. To exploit the benefit of high luminosity, the electronics must also be able to cope with a high input trigger rate (30 kHz) and have buffer memory which is deep enough to wait for a trigger decision ( > 5 μ s ). The TOP electronics has switching capacitor arrays to sample waveforms with 2.7 GSample/s, which allows a timing resolution of 50 ps for a single photon signal. The programmable logic and the processing system are the effective implementation to meet these requirements, where flexible optimization and step-by-step development of readout logic are possible. The system has been successfully operated in the first accelerator commissioning runs with beam collisions in 2018, where the typical trigger rate was 500 Hz . Operation with a 20 kHz trigger rate was also tested.

Introduction/objectives In humans with impaired right-sided cardiac function, the caudal vena cava (CVC) diameter serves as a marker of venous congestion. This study aimed to investigate whether ultrasonographic CVC variables could identify the presence of right-sided congestive heart failure (R-CHF) in dogs with right-sided heart disease (RHD). Animals Fifty client-owned control dogs and 67 dogs with RHD were enrolled. The dogs with RHD were subdivided into the non-R-CHF (n = 43) and R-CHF (n = 24) groups. Materials and methods We measured and compared the ultrasonographic CVC variables and echocardiographic variables among the groups. Receiver operating characteristic (ROC) curve analysis was performed to calculate the sensitivity and specificity of the variables at optimal cutoff values. Results We obtained the highest accuracies of the ratio of the shortest diameter (SD) of the minimal CVC area to the aorta diameter (Ao) during inspiration [SD(min)/Ao] and of the ratio of SD(min) to the longest diameter of the minimal CVC area during inspiration [LD(min),SD/LD(min)], with high sensitivities, specificities, and an area under the ROC curve greater than 0.925. Conclusions In addition to the echocardiographic assessment of right-sided cardiac function, the CVC variables in this study, especially SD(min)/Ao and SD/LD(min), would be useful diagnostic indices for identifying R-CHF in dogs with RHD.

We developed a new particle identification device, named TOP counter, for the next B-factory "Belle II" experiment. We produced 17 TOP counter modules and installed 16 modules into the Belle II structure. We will present the R&D items after the installation, such as issues on operation in the magnetic field, further investigation to achieve a longer lifetime of the MCP-PMT and the performance of the readout electronics.

An RF acceleration system, in which digital control with a direct digital synthesizer (DDS) is applied, has been developed for the Heavy Ion Medical Accelerator in Chiba (HIMAC) synchrotron. This digital system allows us to obtain stable operation of the acceleration system over a wide frequency range from 1.04 to 7.9 MHz. In this paper the designed digital RF control system and its performance are described.

Objective : To investigate the effect of muscle-tone-reducing procedures (MTRPs), i.e. partial nerve block by lidocaine (PNB) and surgical release of muscle attachment to bone (SRMAB), on incessant involuntary head movements in athetotic patients. Methods : Pre/post-MTRP changes in neck-muscle activities, glabella movement and maximum isometric forces of the head were measured in six athetotic patients with severe spondylotic myelopathy resulting from incessant involuntary head movements. Results : Pre/post-MTRP changes in neck-muscle activities resembled those after gamma-block. In four patients, PNB reduced the maximum isometric force by no more than 40% of pre-PNB force, while decreasing the amount of involuntary head movements to 37–65% of the pre-PNB value in the frontal plane. MRSAB reduced the force by less than 40% of pre-SRMAB force in 4 MRSAB tested patients, while decreasing the amount of involuntary head movements to 12–45% of the pre-SRMAB value in all 6 patients. Conclusion : MTRPs reduced involuntary head movements significantly while preserving voluntary muscle forces relatively well. PNB and SRMAB procedures have in common the effect of reducing gain in the myotatic reflex pathway by decreasing the excitatory inflows to alpha-motoneurons via muscle spindle Ia-afferents, which resulted from blocking mainly gamma-efferent conduction by PNB, and reducing background tension in muscle spindles by SRMAB.

The kinetic modeling of oil cracking by hydrothermal pyrolysis experiments using a Japanese oil, derived from type II kerogen, is reported here. Pyrolysis experiments were carried out in the temperature range from 370 to 410°C and the time range from zero to 384 h. The chemical structural analysis of the product oils by 1 H NMR and by elemental analysis provided important information for the kinetic modeling. The kinetic model to characterize changes in amount of hydrocarbon gas, light saturates, light aromatics, heavy saturates, heavy condensed aromatics, heavy non-condensed aromatics and coke was finally constructed. The apparent activation energy for cracking of heavy saturates was found to be 76 kcal/mol, which is close to a value published on hexadecane cracking under high pressure in anhydrous conditions. Application of the model to geological conditions shows that the cracking of heavy saturates occurs within a temperature range of 190 to 230°C, which is relatively a higher range than that usually accepted in petroleum geochemistry.

The influence of metatarsophalangeal lesions on the position of the center of plantar pressure in rheumatoid patients was analyzed by a photoelastic method. Fifteen patients were divided radiographically into three groups (A to C) based on the degree of destruction of the metatarsophalangeal joints. Fifteen age-matched non-rheumatoid subjects were studied as a control group. As parameters expressing the position of the centre of plantar pressure, longitudinal ratio (λ) and transverse ratio (η) were defined and analyzed respectively. the λ of group B was significantly lower than those of group A and C (A: 44.6 ± 6.4, B: 39.0 ± 0.5, P = 0.0327; B: 39.0 ± 0.5, C: 44.7 ± 4.9, P = 0.0075). The η of group B was significantly lower than those of group A and C (A: 46.2 ± 3.4, B: 43.4 ± 7.4, P = 0.0161; B: 43.4 ± 7.4, C: 46.4 ± 1.9, P = 0.0075). By comparing the above data with the control data and combinations of patterns in both parameters, the positions of the centre of plantar pressure were divided into four types. The most common type in group A and C was ‘anterolateral (steady)', and that in group B was ‘posteromedial (unsteady)'. Based on the result, we conclude that the treatment of the lesions in group B is the most necessary to maintain the stability of standing.

This paper describes the design and performance of a 10-Gb/s laser diode (LD) transmitter and avalanche photodiode (APD) receiver, both of which are based on GaAs MESFET IC's. The LD transmitter consists of a strained MQW distributed-feedback LD and one chip LD driver IC. The module output power is +4.6 dBm at 10 Gb/s. The APD receiver consists of an InGaAsP/InAl/As superlattice-APD and an IC-preamplifier with the 10-Gb/s receiver sensitivity of /spl minus/27.4 dBm. As for the LD transmitter, we discuss the optimum impedance-matching design from the viewpoint of high-speed interconnection between LD and driver IC's. As for the APD receiver, the key issue is input impedance design of preamplifier IC, considering noise and bandwidth characteristics. Total performance of the transmitter and receiver is verified by a 10-Gb/s transmission experiment and a penalty-free 10-Gb/s fiber-optic link over 80 km of conventional single-mode fiber is successfully achieved. >

Astrocytes perform a variety of functions in the adult central nervous system (CNS). Recent evidence suggests the robust upregulation of glial fibrillary acidic protein (GFAP) after CNS insult. However, little is known about the role of GFAP in the hippocampal degeneration after brain injury. We herein compared the GFAP knockout (KO) and wild type (WT) mice on the histological and behavioral outcome in response to cerebral trauma or kainic acid (KA)-induced seizure. Although all KO mice showed hippocampal CA3 neuronal degeneration. WT mice did not show any neuronal degeneration in CA3 subfield at 72 hrs after trauma. Thereafter, KO mice showed a higher susceptibility to KA-induced seizures and an increased number of pyknotic CA3 neurons 72 hrs after KA administration. These results indicate that GFAP plays a crucial role in the hippocampal neurodegeneration after CNS insult.

Vascular endothelial growth factor (VEGF) is known to be a mediator of angiogenesis and vascular permeability. A cystic component and hemorrhage are often found in pituitary adenomas. In the present study we assess the VEGF expression based on immunohistochemical examinations in 48 pituitary adenomas. All the adenomas showed some VEGF immunoreactivity mainly in the cytoplasm of tumor cells. Of the 48 adenoma-cases, 16 cases had a strong VEGF immunoreactivity, 26 cases had a moderate one, and 6 cases had a weak one. On the MR images, a cystic component was found in 16 cases (33.3%), and a hemorrhage was found in 18 cases (37.5%). The VEGF immunoreactivity had a significant relationship with the cystic component but neither the hemorrhage, size, recurrence, or HE classification. These findings suggest that VEGF might play a potential role in the pathogenesis of cystic formation in pituitary adenomas.

Mitogenic stimulation of the Mitogen-activated protein kinase (MAPK) pathway modulates the activity of many transcriptional factors leading to biological responses. Of these, three MAPK cascades are well characterized as extracellular signal-regulated protein kinase (ERK), c-Jun NH(2)-terminal kinase (JNK), and p38 pathways. The aim of this study was to investigate the topographic distribution and the role of activated MAPK pathways after fluid percussion injury (FPI) in rats. In the present results, FPI significantly induced ERK- and JNK-phosphorylation, but not p38-phosphorylation in the cortex and hippocampus at the injury site. The immunoreactivity for phospho-ERK was localized in the superficial neuronal layers, dentate hilar neurons, and the damaged CA3 neurons after 30 mins of FPI. Double immunostaining showed that phospho-ERK was prominent in astrocytes 6 hrs after TBI. The current results suggest that MAPK pathways are involved in signal transduction after FPI.

Optoelectronic integrated and photonic integrated devices used as key components in high-performance, compact, and cost-effective optical modules for subscriber optical network systems such as fiber-to-the-home/office (FTTH/FTTO) and fiber-to-the-curb (FTTC) are described. A laser diode with a monolithically integrated monitor photodiode and monolithic receiver optoelectronic integrated circuits (OEICs) are shown to be promising components for achieving optical module compactness and cost-effectiveness. Wavelength division multiplexer (WDM) filters and couplers/splitters based on PLC (planar lightwave circuit) technology, silica waveguides on silicon substrate, are shown to make high-performance, compact integrated devices for WDM optical modules. A compact WDM optical module accessing simultaneously to 1.3- mu m-wavelength time compressed multiplexing (TCM) signals and 1.5- mu m-wavelength video signals is described. >

HIMAC, the Heavy Ion Medical Accelerator in Chiba, is the first heavy ion accelerator dedicated to medical applications. The two 800 MeV/u synchrotron rings are controlled by a computer system. Testing in part has been started and preliminary results are successful. The testing of the whole control system is scheduled to be completed by the end of October 1993.

The successful development of a low-cost laser-to-fiber coupling module for single-mode subscriber use is reported. The module consists of a laser collimator and a fiber collimator with a microball lens in each collimator, that is, a two-microball-lens system in a confocal condition. The key technology of this module is the high-precision bonding of a microball lens in front of a laser diode using a recently developed ultraviolet (UV)-curable resin. An average coupling efficiency of -4.7 dB with a standard deviation as small as 0.37 dB is achieved. It is found that the resin has good bonding durability and the module is stable under a temperature cycle test of over 1400 cycles. Simple structure and high reproducibility of the module have reduced the cost. A monolithically integrated laser diode and photodiode (LD-PD) are also developed. An output efficiency as high as 0.03 W/A is achieved in a 10-60 degrees C temperature range by combining the LD-PD with the module. >

To find out the distribution of nerve endings in the dural sheath of cervical nerve roots and to study the mechanism of cervical radicular pain.2069 20 microm serial sections were made from 39 cervical root-dorsal root ganglion specimens obtained from 18 postmortems. By using optical microscope and Suzuki silver impregnation method and Klüver-Brrera method, we examined the morphology, quantity and distribution of the nerve ending in the nerve sheath of the root, dorsal root ganglion (DRG) and the spinal nerve of these sections.There were several kinds of nerve endings such as free nerve endings in the nerve sheath of the root, the dorsal root ganglion, and the spinal nerve. Free nerve endings were distributed in the proximal and distal portions of DRG sheath more extensive than that in other parts of the dural root-sheaths.The free nerve endings in the dural root-sheaths especially those in the DRG sheath are thought to play an important role in cervical radicular pain.

Hepatocyte growth factor (HGF) was originally discovered as a powerful mitogen for hepatocytes. HGF functions both as a neurotrophic factor as well as an angiogenetic factor. Furthermore, HGF has an anti-apoptotic effect on vascular endothelial cells. The present study examined the neuroprotective effect of HGF after transient focal cerebral ischemia in rats, in which an anti-apoptotic and an angiogenetic effect of HGF was assumed to contribute to the reduction of the infarct volume. The intraventricular administration of human recombinant HGF (90 micrograms) significantly reduced the infarct volume after 120 minutes occlusion of both the right middle cerebral artery (MCA) and the bilateral common carotid arteries (CCAs). In a separate series of experiments, we investigated both the anti-apoptotic effect on neurons and the angiogenetic effect of HGF histopathologically. The number of survival neurons and vascular lumina in the HGF group were significantly higher than those in the vehicle group. A large number of TUNEL positive neurons were observed in the inner boundary of the infarct area in the vehicle group, whereas only a few TUNEL positive neurons were observed in a corresponding area in the HGF group. In the HGF group, Bcl-2 protein was obviously represented in survival neurons as well as in vascular endothelial cells and in glial cells subjected to ischemia. These data suggest that HGF prevents apoptotic neuronal cell death by upregulating the production of Bcl-2 protein and by an angiogenetic effect in the central nervous system which affected transient focal cerebral ischemia.

To clarify the mechanism of ischemic tolerance induced by HBO, we investigated the effect of HBO on immunoreactivity to Bcl-2 and Bax, apoptosis-regulating protein, or Mn-SOD, a radical scavenging system, in the CA1 sector of the gerbil hippocampus. Pretreatment comprising, five sessions at 2 ATA (atmosphere absolute) every other day, but not that comprising, ten sessions at 3 ATA every day, caused significant increases in Bcl-2 and Mn-SOD immunoreactivity in the CA1 sector compared with in the sham pretreatment group. No significant differences in Bax immunoreactivity and neuronal density in the CA1 hippocampal neurons was observed between the groups. These results suggest that protection against mitochondrial alterations after ischemia through Mn-SOD and/or Bcl-2 expression is related to the ischemic tolerance induced by repeated HBO pre-treatment.

In this study, extracellular glutamate (Glu) was monitored in real time using a biosensor following traumatic brain injury (TBI) either with or without inducing hypoxia in the rat Fluid-percussion model. We also measured the cortical contusion volume at 3 days after the insult. The animals were divided into 3 groups. Group 1 was subjected to TBI only, Group 2 to TBI followed by 20 min of moderate hypoxia (FiO2: 10%) and Group 3 to 20 min of moderate hypoxia without TBI. The surge increase in the extracellular Glu concentration occurred immediately after TBI in Groups 1 and 2. Group 2 showed a prolonged efflux of Glu during hypoxia. Group 3 Glu showed low continuous steady levels. The contusion volume in Group 2 was significantly larger than in Group 1. To test the possible involvement of apoptosis in Groups 1 and 2, rats were sacrificed at 1, 6, 24 and 72 h after TBI. Immunohistochemical studies showed an increased number of both CPP32 positive cells at 24 h and TUNEL cells at 72 h in Group 2. These results suggest that TBI with moderate hypoxia induced a prolonged efflux of Glu that resulted more cortical damage due to necrosis and apoptosis.

To clarify the influence of intubation maneuver with or without premedication for intracranial hemorrhage with unconsciousness.Between May 1995 and May 2000, we analyzed retrospectively 46 patients who had received intubation for unconsciousness and were found non-traumatic intracranial hemorrhage by head computer tomography at the Trauma and Critical Care Center, National Defense Medical College. They were divided into two groups, Drug group in which drugs were used before intubation and Control group which were intubated without drugs. Physical findings on admission, head CT findings, Glasgow Outcome Score(GOS) at discharge were analyzed between the groups.There were no significant differences for background of subjects between the groups. In the Drug group, diazepam, pentazocine, lidocaine, nifedipine and nicardipine were used before intubation. GOS in the Control group was significantly greater than in the Drug group(p0.01).In case of intubation for unconscious patients who may suffer intracranial hemorrhage, using premedication leads to favorable outcome.

A case of an acute subdural hematoma due to the rupture of a tiny aneurysm of a cortical artery is described. A 68-year-old man lightly hit the right side of his head. About 1 hour later, he became drowsy and exhibited moderate hemiparesis on the left side on admission. Computed tomographic scanning demonstrated an acute subdural hematoma on the right temporoparietal region. In the past, he had undergone the clipping of a non-ruptured aneurysm and a subdural-peritoneal shunt operation on the same side in another hospital. On surgical evacuation of the subdural hematoma, a pulsating bleeding from a ruptured tiny aneurysm of a cortical artery was observed. There were also some similar tiny aneurysms on other cortical arteries. A photograph of such a tiny aneurysm was first taken and presented.

We herein describe thallium-201 single photon emission tomography (T1-201 SPECT) findings in three cases with intracranial angioma. One of the lesions which was associated with chronic encapsulated intracerebral hematoma showed moderate accumulation of T1-201, but, others demonstrated no accumulation. The usefulness and limitations of T1-201 SPECT in differential diagnosis of intracranial mass lesions are discussed.

A 58-year-old female presented with a rare case of intracranial solitary fibrous tumor (SFT) manifesting as progressive ataxic gait and hearing loss on the left persisting for 6 months with recent symptoms of increased intracranial pressure. Computed tomography demonstrated a large isodense irregular-shaped mass in the left posterior cranial fossa. T2-weighted magnetic resonance imaging showed two components appearing as very low intensity and high intensity. Extreme-lateral suboccipital craniotomy was performed. Gross total resection was achieved except for some dural attachment in the jugular foramen. All symptoms and signs subsided after surgery. Histological, immunohistochemical, and electron microscopic examinations led to a diagnosis of SFT. The strongly hypointense areas on the T2-weighted images were hypocellular region characterized by disorganized spindle cells and thick bands of collagen. The hyperintense areas on the T2-weighted images were hypercellular region mimicking hemangiopericytoma. Strong immunoreactivity for CD34 was also helpful in the diagnosis. Electron microscopy revealed absence of pinocytic vesicles and dense laminae which are characteristic of hemangiopericytoma. The magnetic resonance imaging appearance of SFT seems to be pathognomonic.

The authors present a case of bilateral chronic subdural hematoma with communication between the hematoma cavities. This 24-year-old male had hit his forehead while playing football and visited our hospital. An initial plain CT scan revealed extracerebral low density areas in the bifrontal region, which were considered to be post-traumatic subdural hygromas. The lesion was followed up with repeat CT scans. On plain CT scan performed seven weeks after the injury, the lesion had evolved into bilateral chronic subdural hematoma and the patient was admitted to our ward. He underwent burr hole drainage on the left side, because the hematoma volume on the left side was considerably larger than that on the right side. A plain CT scan on the day following the operation revealed complete resolution of the hematomas on both sides. A favorable re-expansion of the brain was confirmed on consecutive CT scan performed two months after the operation. In general bilateral chronic subdural hematomas in adults are considered to have no communication between the hematoma cavities and therefore they should be evacuated on both sides simultaneously. In our case, on the contrary, the operation revealed a communication between the hematoma cavities. The falx cerebri is narrow in front and this narrow anterior part is frequently perforated by one or more apertures. We attributed the communication to this anatomical feature of the falx cerebri. On preoperative CT scan, in addition, the inner surface of the bifrontal hematoma cavity demonstrated a smooth concave figure indicating retrospectively that the cavity on the left side was continuous with that on the right side.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of growing skull fracture was reported with some considerations on the literature. At the age of 1 year, the patient fell down stairs and struck the right occipital region, but did not receive any treatment at that time. At the age of 19 years, he suffered from several epileptic attacks and was admitted to our ward. Plain craniograms showed a right occipital bone defect measuring 7 x 3 cm in size. CT scan demonstrated a cystic lesion just beneath a membranous substance existing at the bone defect. MRI revealed cystic encephalomalacia underlying the cyst very clearly. At the operation the bone defect was found to be replaced by the granulation tissue which was examined microscopically. Under the granulation tissue, a cyst filled with yellowish fluid and surrounding gliotic brain was found. The dural tear was noticed to be much wider than the bone defect. A dural plasty with LYODURA and a cranioplasty with methacrylic resin were performed. Microscopic examination revealed the granulation tissue to be a fibroglial cicatrix. According to these findings, we concluded that the contused and swollen brain tissue which had herniated through the dural tear had enlarged the skull fracture and formed a fibroglial cicatrix with subcutaneous tissue. It is emphasized that MRI combined with CT scan is an indispensable procedure for diagnosis of growing skull fracture, and microscopic examination contributes to an understanding of its pathogenesis.

A 21-year-old man was hospitalized with complaints of headache, nausea, polyuria, reduced body hair and reduced libido. Plain CT scan and MRI revealed multiple tumors in the pineal and suprasellar regions, and in the dorsal aspect of the medulla oblongata. Endocrinological examination showed hypopituitarism due to hypothalamic dysfunction. Replacement therapy with hydrocortisone was started preoperatively. Suprasellar tumor was explored. Postoperative CT scan and MRI showed marked diminishment of not only suprasellar tumor, but also tumors in the two other regions. These tumors were supposed to be sensitive to corticosteroid hormone. Histopathological diagnosis was T cell type malignant lymphoma. The patient was followed up for 10 months post-operatively with no recurrence on CT scan. Primary intracranial malignant lymphoma is not a rare disease today. However, primary intracranial T cell type lymphoma is extremely rare. Hypopituitarism due to suprasellar malignant lymphoma is also rare, and only 3 such cases have been reported previously. In our case, the tumor was located in the pineal and suprasellar regions, and the dorsal aspect of the medulla oblongata. Such disseminated malignant lymphoma as ours shows radiological resemblance to germ cell tumor. No such diseminated malignant lymphoma has been reported previously. We think that, in its radiological and clinical features, our case is very suggestive of primary intracranial malignant lymphoma.

A 28-year-old woman was hospitalized in drowsy state with signs of increased intracranial pressure. CT scans revealed diffuse increased density with marked enhancement in the subarachnoid space, as well as ventricular dilatation. V-P shunt operation was performed to control intracranial pressure. Repeated cytological examinations of CSF couldn't determine the tumor origin. CT scan of thoracic spine showed a cystic tumor in its dorsal aspect. T2-weighted MRI revealed multiple spotty low intensity, specific to melanin granules, throughout the whole spine. Her thoracic spine was explored, and the intradural tumor was partially removed. Histopathological examination revealed the tumor cell which had dark nucleus with conspicuous nucleolus and cytoplasmic granules. These findings were compatible with malignant melanoma. Her general condition were deteriorated progressively and she died about 5 months after her admission. Postmortum examination showed diffuse leptomeningeal invasion of dark tumor throughout the entire central nervous system, and metastasis to peritoneum and omentum via V-P shunt system. Histopathological examination proved the tumor to be malignant melanoma. Electrone microscopic examination also revealed melanosome in the cytoplasm. Primary intracranial malignant melanoma is divided in two groups, nodular type and leptomeningeal type. In the latter type, early diagnosis is very difficult, just as in our case, because only a little tissue specimen can be obtained. In a case of leptomenigeal carcinomatosis, possibility of primary malignant melanoma, though rare, should always be kept in mind, and specific staining such as Fontana-Masson's staining should be tried.

In order to assess effects on conductivity of the spinal nerve roots which were compressed due to lumbar disc herniation (LDH) and spinal canal stenosis (SCS) at the lumbosacral vertebrae, spinal nerve root potentials (SRP) were recorded epidurally at multiple levels upon stimulation of the tibial and peronea nerves. Subjects were five normal volunteers and fifteen clinical cases (10 LDH and 5 SCS). Simultaneous recording of evoked EMGs was used to identify afferent and efferent components of SRPs. The shortest latency SRP consisted of orthodromic group I afferent and antidromic alpha-efferent potentials. The potential on liminal M-wave stimulation was regarded as representing exclusively group I volley and that on maximal M-wave stimulation as predominantly alpha-efferents. A centrifugally conducting nerve potential for H-reflex could be also recorded. Conduction blockage in the lumbar spinal roots of the clinical cases could be recognized as increased positivity and desynchronization. Quantitative assessment of these signs was devised in comparison to the control data. The present method revealed at least one of these signs in all clinical cases, and was found useful to determine the levels at which surgical decompression is indicated, supplementing radiological examination.

A 45 year old woman presented with swelling and pain on joint movement of her knees, although joint movement was relatively well maintained. Five years previously the patient had been diagnosed as having pustulosis palmoplantaris by a dermatologist. Treatment with non-steroidal anti-inflammatory drugs (NSAIDs) had no effect, but treatment with 5 mg/day prednisolone caused remission of both the joint pain and swelling and the pustulosis palmoplantaris. There were no sternocostoclavicular lesions at any time during treatment. Clinical findings in this patient were different from previous reports and she was diagnosed as having palmoplantar pustulotic arthro-osteitis affecting the peripheral joints.

Synovial osteochondromatosis of the foot is a rare disorder. We present the first report of synovial osteochondromatosis of the intermetatarsal/tarsometatarsal joints. When a mass develops in the sole of the foot and heterotopic ossifications are revealed radiographically, synovial osteochondromatosis should be considered in the differential diagnosis.

We have developed a new surgical approach to the atlas and the axis including the odontoid process, in which the vertebral artery is transposed and an access to their lateral aspects without exposing the anterior structures of the neck is achieved. A case of successful excision of a bone tumor of the lateral mass of the atlas and a hypertrophic odontoid process by this approach is described.

This report compares tissue irritation by a newly developed calcium-based root canal filling material with irritation by previously available materials and evaluates the toxicity of various components in the root canal filling material. Polyethylene tubes filled with root canal filling materials were implanted in rat subcutaneous tissue, enucleated after 2, 4, 8 and 12 weeks, and histopathologically evaluated for tissue reaction. The tissue inflammation was microscopically evaluated and divided into 4 grades. The new root canal filling material has good tissue affinity compared to prior material. Transmission electronic microscopy and X-ray analysis revealed: titanium in AH-26; barium and bismuth in Canals, Tubli-seal and the newly developed root canal filling cement A; and zinc in the root canal filling cement B. Tissue was variously inflamed and, occasionally, necrosis was induced in the cells. The newly developed root canal filling cement A, showed better tissue affinity and no or slightly morphology change.

Manufacturing narrow track magnetic heads is difficult as track widths become very narrow. A new flying-head manufacturing method is established by applying ion-etching. Optimum conditions for ion-etching of the ferrite material were determined. More than 10 μm ion-etched depth and even less than 5 μm track width were obtained. Through experimental and theoretical evaluation, it is proven that ion-etched heads have equivalent or better read/write characteristics than mechanically manufactured heads.

A new kind of 1-μm bubble device with two ion-implanted layers between propagation tracks has been studied. The ion-implanted layer in the center between two adjacent propagation tracks is thinner than that in the vicinity of the propagation track edge, where bubbles adhere. The unimplanted area is produced by the use of both photoresist and Mo masks to stop the ions, whereas the thinner implanted layer is produced by the use of the thin Mo mask alone. The ion-implantation mask-making for fabricating two ion-implanted layers is achieved with a gas plasma etch procedure. This structure makes it possible to scale down a loop period and create a circuit of high density. Reliable propagation margins for minor loops with 4 × 3 μm cell sizes can be obtained.

In InGaAsP/InP buried heterostructure (BH) lasers, the degradation of BH interface between first- and second-growth step layers can be suppressed by employing the melt back process just before the second-step layer growth. It is confirmed this burying process give more reliable BH lasers than the conventional burying process. From the viewpoint of BH interface degradation, lasers lasing at 1.5 μm, where the melt back process naturally occurs during BH formation, are found to be more reliable than those lasing at 1.3 μm.