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The diagnosis of spinal dural arteriovenous fistula (SDAVF) is difficult and often delayed because clinical features are often nonspecific. We assessed the motor function electrophysiologically in patients with SDAVF.Motor-evoked potentials after transcranial magnetic stimulation and compound muscle action potentials and F-waves after electrical stimulation in the ulnar and tibial nerves were measured from the abductor hallucis (AH) muscles in 14 patients with SDAVF (SDAVF group), 12 patients with compressive thoracic myelopathy (CTM group), and 16 normal subjects (control group). The peripheral conduction time determined from abductor hallucis muscles (PCT-AH) and the central motor conduction time determined from abductor hallucis muscles (CMCT-AH) were calculated. According to the neurological findings, patients in the SDAVF group were classified to upper motor neuron (UMN) sign and lower motor neuron (LMN) sign categories.CMCT-AH in the SDAVF and CMT groups were significantly longer than those in the control group. PCT-AH in the SDAVF group was significantly longer than that in the control and CMT groups. Twelve patients in the SDAVF group showed abnormal CMCT-AH and/or PCT-AH. Abnormal CMCT-AH and PCT-AH were detected in five cases that exhibited UMN sign and/or LMN sign. Three cases with abnormal CMCT-AH and normal PCT-AH exhibited UMN sign. LMN sign without UMN sign was observed in four cases with abnormal PCT-AH and normal CMCT-AH.Our study revealed abnormalities in the corticospinal tract and/or lower motor neurons, and classified the patients with SDAVF into three types: the UMN type, LMN type, and mixed type.

In cruciate-retaining (CR) type TKA, the increase in posterior condylar offset (PCO) is considered to be correlated to flexion angle acquired postoperatively according to the article reported by Bellemans (J Bone Joint Surg Br 84:50-53, 2002). However, the significance of PCO seems to differ according to the size of joints. We therefore have defined a new parameter of posterior condylar offset ratio (PCOR) on the lateral view of plain X-ray photographs and studied the relationship between PCOR and postoperative flexion status in posterior-stabilized (PS) type TKA. Flexion status includes two parameters, such as postoperative flexion angle (FA) and flexion achievement rate (AR). The subjects of this study were 160 knees (16 males and 144 females, average 75 years.) with PS type TKA for osteoarthritic knees between 1999 and 2003 at our institution, more than at least 1 year postoperative follow-up. In the study of FA, patients with FA of less than 100 degrees were divided into Group L (n = 28), patients with FA of 130 degrees and greater were divided into Group H (n = 58). In the study of AR, patients with AR of less than 100% were divided into Group P (n = 46), patients with AR of 120% and greater were divided into Group G (n = 22). PCOR was statistically compared in each group, respectively. In FA, PCOR in Group L (0.385) was significantly lower (P = 0.027) than that in Group H (0.428). In AR, PCOR in Group P (0.376) was significantly lower (P = 0.0018) than that in Group G (0.456). We have concluded, though there are many factors influencing the range of movement after TKA, our newly defined PCOR could possibly serve as a parameter of postoperative flexion status of PS type TKA on plain X-ray photographs.

Recording at a high density four times that of a current digital versatile disk random access memory (DVD-RAM) has been achieved by applying the domain wall displacement detection (DWDD) technology using a conventional optical head with the same wavelength of 660 nm and numerical aperture (NA) of 0.60 as those the DVD head. It has been confirmed by using an alternating sampled servo, laser annealing of the inter track area and partial response maximum likelihood (PRML) that a recording density of 15 Gbit/inch2 with a track pitch of 540 nm and bit length of 80 nm has sufficient system margins. A newly developed 1-bit-distributed address format has achieved a redundancy of 23%. Furthermore, the edge shift compensation technique has reduced the recording magnetic field. These indicate that a capacity of 3 GB on a two-inch-diameter disk is now available for mobile use. If applied to a digital video camera, one hour or more of moving-picture-experts-group-2 (MPEG2) video contents can be recorded at a bit rate of 6 Mbps.

Intraspinal ganglions of cervical facet joints are rare. Those reported have occurred in the lumbar region. We report a case of an intraspinal ganglion of the cervical facet joint causing radiculopathy (C8 root). The patient was a 69-year-old man admitted with a history of severe pain in the right upper extremity. The pain radiated to the right scapula and forearm. At MR imaging, a ganglion of the facet joint was delineated as a smooth extradural well-circumscribed cystic mass arising adjacent to degenerative facet joint (C7/T1). Surgical therapy resulted in satisfactory recovery.Two types of cysts that are known to originate from the facet joint are the synovial cyst and the ganglion. Synovial cysts have a histologically identifiable synovial lining and contain clear fluid, whereas ganglion contains gelatinous, highly viscous fluid, has a connective tissue capsule, and lack of a specific lining. This case was ganglion because of lack of a specific lining and gelatinous, highly viscous fluid.

Practical optics for a cover-layer incident dual-layer disc with an NA=1.45 hemispherical solid immersion lens are designed, using a spherical aberration compensating liquid crystal cell. A hybrid servo system, gap servo for NA >1 and focus servo for NA < 1, is proposed. Keywords: near field recording, SIL, solid immers ion lens, spherical aberration compensation 1. INTRODUCTION In the past few years, there have been many studies on near field recording (NFR), such as by Ishimoto et al. [1] and Verschuren et al. [2] Verschuren et al. proposed a cover-laye r incident dual-layer (DL)-dis c with a hemispherical solid immersion lens (SIL) and presented an improved design of a hemispherical SIL and bi-aspherical lens that is able to focus free from wavefront aberration through a 3P m cover-layer [3]. The first section describes the practical design of the cover-layer incident DL-disc with a hemispherical SIL without change in dist ance between the first lens and the SIL based on the previous report. On the other hand, a gap servo is an excellent technique of achieving near field recording. However, a DL-disc also requires an accurate focus servo sy stem, in order to accomplish focus jump between layers, wide tolerance of the thickness of the cover/space layer and wide tolerance of the change in wavelength of the laser diode (LD). The second section proposes a hybrid serv o system combining a gap servo and a focus servo.

A case report of a 55-year-old patient with extensive cervicothoracic ossification of the posterior longitudinal ligament (OPLL) that was treated with posterior decompression and fusion.To report the preventive effect of posterior instrumentation on postoperative paralysis in extensive cervicothoracic OPLL.Thoracic myelopathy caused by OPLL in the thoracic spine was treated with operative decompression of the spinal cord via an anterior, posterior, or posterolateral approach. However, the lack of availability for some approaches in specific cases, as well as reports of some problems for each approach, indicates that a lack of consensus still remains regarding the choice of operative procedure.A 55-year-old female with extensive cervicothoracic OPLL presented with progressive numbness in the both hands and a gate disturbance. Cervical laminoplasty, thoracic laminectomy, and posterior fusion were performed with electrophysiologic monitoring of the spinal cord evoked potential.After thoracic laminectomy, the amplitude of spinal cord evoked potential waveforms decreased but recovered after a posterior fusion by instrumentation.Prevention of postoperative paralysis from increasing by posterior instrumentation was shown using neurophysiologic monitoring.

Study design Case reports of patients with cervical myelopathy to hypoplasia of the atlas. Objectives To report cases of cervical myelopathy due to congenital hypoplasia of the atlas and to review the literature. Summary of background data Six previously documented cases of congenital hypoplasia of the atlas as a cause of cervical myelopathy are reported in the literature. Methods Three patient's clinical record and radiologic imaging studies as well as a thorough literature search are reported. Plain radiographs, computed tomography scans, magnetic resonance images, as well as somatosensory-evoked potential changes are displayed. Results Cervical myelopathy developed in three patients who were found to have congenital hypoplasia of the atlas. Laminectomy of C1 provided neurologic improvement in all three patients presented. Conclusion Congenital hypoplasia of the atlas is a rare cause of cervical myelopathy. This report should broaden the radiographic differential diagnosis when seeking an explanation for the signs and symptoms of cervical myelopathy.

"They are very good at making false statements," says Koichiro Nishikawa, as he sits in his new office at the KEK particle-physics lab in Tsukuba, Japan, 40 km north east of Tokyo. He should know. What Nishikawa is referring to are neutrinos – ghostly subatomic particles that he has spent almost his whole life trying to study. With no electric charge, a minuscule but nonzero mass and a radius eight orders of magnitude less than an atom, neutrinos interact so weakly with matter that vast detectors are usually required – and plenty of patience too.

Neutrino physics is largely an art of learning a great deal by observing nothing (Haim Harari, 1988) was our general understanding of the field for the ~25 years previous. A new neutrino era was abruptly brought from outer space by a burst of SN1987A neutrinos. The detection of neutrinos from SN1987A gave a new impetus to neutrino research. As we know, new discoveries of neutrinos have since been made. Neutrinos were no longer mysterious, but attained particle citizenship. Giant liquid argon charge imaging experiments have the prospect of opening the door to the second new era in neutrino physics. The coming era would provoke not evolution, but revolution in particle physics. However, paving the way for the new era requires not evolutionary, but revolutionary detector developments. I hope this workshop will be conducive to reaping a rich harvest from its activities. In 1993, Professor Carlo Rubbia presented The Renaissance of Experimental Neutrino Physics in which he discussed various possibilities of shooting neutrino beams from CERN towards Gran Sasso, Super-Kamiokande at Kamioka and DUMAND in Hawaii. Now KEK hopes to shoot neutrino beams from J-PARC to Kamioka, Okinoshima, Korea and Gran Sasso. Atsuto SuzukiDirector General, KEK J-PARC has moved into a new phase of operation. The commissioning of the accelerator complex and experiment facilities has begun, and it is urgent to attain initial design performance as soon as possible. For the immediate future, KEK has a 5 year plan. The plan includes the upgrade of the J-PARC accelerator to a multi-Mega-Watt facility, and detector R&Ds to form the basis for a next step in the neutrino experiment. One of the main issues of the future neutrino experiment will be the search for CP violation in neutrino oscillation, which demands much more precision than studying neutrino oscillation or non-zero theta13. This naturally requires a very massive detector with higher precision than presently available technologies. In addition, such a detector will also be an excellent detector for the further search for proton decay. The sensitivity of the various methods of extracting CP violation should be carefully evaluated. At the 4th International Workshop on Nuclear and Particle Phyics at J-PARC (NP08) in March 2008, the J-PARC MR power upgrade and the future neutrino experiment were discussed. At the workshop, a comparison of first and second maximum in electron neutrino appearance in muon neutrino beam was discussed. This method is free from systematic errors due to ambiguities of neutrino and anti-neutrino cross sections. On the other hand, this method requires a very massive detector with energy reconstruction capability for a wide range of neutrino energy. Beside the statistical precision, which requires a high power proton accelerator, there are many strict requirements on the detector. Most of the requirements are common to a detector for neutrino physics and to the search for proton decay. We need new ways of looking for new phenomena at a level far beyond on-going experiments. Future experiments should be designed based on new detector technology, improved accelerator technology and the results of present on-going experiments. We are looking forward seeing the outcome. Koichiro NishikawaDirector, IPNS KEK

We have developed a domain wall displacement detection (DWDD) magnetooptical drive for the 2-inch-diameter disc with 3 GB capacity. The newly developed magnetic head and the drive circuit realize the high efficiency of 1.84 Oe/mA and the high speed switching of 13.5 ns. An optical pickup (OPU) with wavelength of 660 nm and numerical aperture (NA) of 0.6 is sufficiently compact to approach the innermost disc radius of 11 mm, and the overall weight is 3.2 g. The volume and power consumption of the entire drive system are 35.5 cc and 0.78 W respectively, and they are adequate for use in mobile storage devices. Furthermore, we have confirmed a complete read/write performance with 15 Gbit/inch2 recording density and 24 Mbps data transfer rate.

A review of 48 cases of Charnley total hip arthoplasty performed on 41 patients is presented. The follow-up period ranged from 1 to 10 years (average of 3 years and 9 months). Clinical evaluation shows that 27 patients (69.9 percent) had over 70 points according to the J. O. A. Hip Score system. On the other hand, from radiographic examination, loosening was found in 13 joints (27.1 percent), and these cases show significantly poorer clinical results. This study shows that the operative technique is the most important point in preventing any loosening. Especially, poor cementing of the stem ands etting the socket have a direct effect on the occurrence of loosening.

Between 1983 and 1988, osteoplastic laminotomy was performed in six cases after tumor extirpation of the cauda equina. Histological examinations of the tumor proved that five were Schwannoma and one was benign cystic teratoma. Surgical procedures were determined by size and location of the tumor. Four cases were treatd by the operative technique reported in 1976 by Raimondi et al. In one case, after extirpation of the left side dumb-bell type Schwannoma between the third and fourth lumbar vertbra, excised spinous process was used for coverage of the spinal canal and postero-lateral fusion was also performed in the affected side. A small and localized tumor was excised with partial hemilaminectomy and resection of the reconstructed spinous process. Reconstruction of posterior part of the lumbar vertebra is important to prevent postoperative kyphosis, anterior subluxation, and instability of the spine especially in children.