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Since the early days of the semiconductor industry, defect control has been key to the successful development of devices and circuits. It requires a thorough understanding of their formation and the impact on the electrical material parameters. This has only been possible by the invention of powerful structural, chemical and electrical characterization tools, with the device itself perhaps as the most sensitive probe. This evolution was paralleled by the development of ab initio calculation methods, based on Density Functional Theory and more recently, also TCAD tools allowing more and more refined modelling of the impact of defects on the electrical characteristics of devices. The implementation of other materials than Si and SiO2 in CMOS through the hetero-epitaxial growth on a silicon substrate for example, has renewed the interest in defect engineering during the last two decades, leading to single-defect analysis methods like Random Telegraph Noise (RTN) [1] or novel growth schemes like Aspect Ratio Trapping (ART) [2] for the removal of extended defects from the device active regions. In this presentation, some state-of-the-art analysis techniques will be highlighted, including Deep Level Transient Spectroscopy (DLTS) [3], Generation-Recombination (GR) noise and RTN spectroscopy [1,4] and p-n diode lifetime analysis [5]. These methods will be applied to several case studies. As shown in Fig. 1, threading extended defects impact the recombination lifetime of lowly-doped n-type In0.47Ga0.53As starting from a density of a few 107 cm-2. Likewise, it will be demonstrated that the GR noise observed in GaN-on-Si MOSHEMTs (Fig. 2) most likely originates from threading dislocations [6]. It is concluded that when hetero-epitaxial layers can be grown with a sufficiently low defect density, their impact will be more on the variability of the electrical parameters rather than on the effective values. In addition, the position of the defect with respect to strategic nodes like a p-n junction or depletion region largely determines its electrical impact, as has been validated by TCAD simulations. References [1] E. Simoen and C. Claeys, “Random Telegraph Signals in Semiconductor Devices”, The Institute of Physics, Bristol, UK (2016). [2] J. Z. Li et al., Appl. Phys. Lett., 91, p. 021114 (2007). [3] E. Simoen, J. Lauwaert and H. Vrielinck, Semiconductors and Semimetals, Eds. L. Romano, V. Privitera and C. Jagadish, 91, pp. 205-250, Elsevier 2015. [4] D. Boudier et al., Solid-St. Electron., 128, pp. 102-108 (2017). [5] Po-Chun (Brent) Hsu et al., J. Phys. D: Appl. Phys., 52, p. 485102 (2019). [6] K. Takakura et al., IEEE Trans. Electron Devices, 67, pp. 3062-3068 (2020). Figure 1

Issue Lifestyle modifications are essential for the prevention of lifestyle-related diseases such as hypertension, hyperlipidaemia, and type 2 diabetes. Healthcare providers in Japan are required to use information and communications technologies (ICT), such as health-related mobile applications (mHealth apps), in health guidance. Description of the Problem To understand the results of and issues in health guidance, two searches were conducted to identify the domains of health guidance provided using ICT. We searched the PubMed and Japan Medical Abstracts Society databases to identify articles published from 2000-2018. The first search identified frameworks of health guidance provided using ICT. The second search identified primary studies about using mHealth apps published between 2000 and 2018. The sample comprised 22 unique programs from 38 primary studies. The following research questions were explored: 1) What is the purpose of using the mHealth app? 2) Is there a significant difference in the effect of using the mHealth app instead of face-to-face communication? Results The mHealth app was used to enhance convenience and to improve or modify lifestyle. The latter included self-monitoring, typing health information, providing knowledge, sharing information, providing encouragement and praise, and correction of action plans. Some positive effects were observed, including compensating for insufficient information, enhancing self-management, and improving degrees of satisfaction of users. Only two programs did not report a significant difference in the effect of using the mHealth app as compared to face-to-face communication. Lessons This review showed that the frequency of typing information about diet and exercise appeared to be related to the prevention of primary lifestyle-related diseases and the improvement of self-management behaviour. Key messages Use of the mHealth app for providing health guidance might enhance continuous support for self-monitoring and self-management behaviour. Use the mHealth app for providing encouragement and praise might promote a smooth conversation, which in turn would facilitate appropriate self-management behaviour.

The applied voltage (Vcc) dependence of SEB characteristics of the Failure In Time (FIT) is generally estimated by the accelerated test, because it takes a long time to cause SEB under the natural condition. So, it is meaningful to confirm the relationship among Field Failure Rate (FFR), SEB, FIT and CBS characteristic. Through physical analysis, the destruction point is confirmed to be located around the electric field peak position during SEB experiment using the neutron irradiation. After both SEB curve fitting and sufficient numbers of analysis for the destruction points, the first major factor to characterize the SEB curve is confirmed to be the electric field strength.

Endoplasmic reticulum (ER) stress, a dysfunction in protein-folding capacity of ER, is involved in many physiological responses including embryonic development. Evidence shows that the ER stress-induced unfolded protein response signaling pathway is associated with impairment of oocyte maturation and pre-implantation embryonic development; supplementation of culture medium with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor, improved the developmental process of oocytes and embryos by attenuating ER stress. However, no reports are available on the role of TUDCA in reducing ER stress during IVM of bovine oocytes. Therefore, the aim of this study was to examine the mechanism of TUDCA on reducing ER stress in maturation of bovine cumulus-oocyte complexes (COCs) and whether inhibition of ER stress during maturation can promote subsequent embryonic development. Bovine ovaries were collected from a local slaughterhouse, and after aspiration COCs were matured with/without TUDCA (50, 100, and 200 µM) for 22h at 38.5°C in a humidified atmosphere of 5% CO2. After IVM, we examined the maturation rate, reactive oxygen species, apoptosis, protein/mRNA expression levels, and subsequent embryonic development after IVF. The data were analysed using analysis of variance followed by the Tukey-Kramer multiple comparison test. As a result, the dose-dependent experiment shows that a 100μM concentration of TUDCA significantly increased the maturation rate and decreased the percentage of apoptotic cells in COCs and reactive oxygen species levels in denuded oocytes. Subsequently, the expression of ER stress inducible protein GRP78/BIP significantly decreased in COCs treated with 100 µM TUDCA compared with the control COCs. In addition, the mRNA expression of ER stress and pro-apoptotic markers (GRP78/BIP, PERK, IER1, ATF4, XBP1, CHOP, and BAX) in COCs were significantly decreased by TUDCA (100 µM) treatment, whereas it increased anti-apoptotic BCL2 expression. Moreover, we show that TUDCA (100 µM) supplementation enhances embryonic development by significantly increasing the blastocyst formation rate (43.6±1.8% vs. 49.7±1.3%) and decreasing the number of apoptotic cells (7.7±1.1% vs. 5.03±0.6%) in blastocysts. These findings suggest that existence of ER stress during maturation alters the developmental competence of bovine COCs. Therefore, for the first time, we demonstrate that application of TUDCA during IVM plays a crucial role in reducing ER stress and improves the meiotic maturation, oocyte quality, and subsequent embryonic development invitro.

Through the physical analysis, the first and minimum destruction point of the power semiconductor chip is precisely identified as around the main pn junction. It well agrees with the Impact Ionization (I/I) peak enhanced by an electric field crowding. A simple device simulation approach, which uses a visible light approximation (optical generation) instead of a high energy radiation ion, is effective to trace the SEB phenomenon. Several fundamental settings were studied to simulate the experimental results.

Modified meshless methods are proposed by choosing trial and test functions from a variety of functional spaces. The accuracy of the proposed methods is evaluated for two ways of imposing essential boundary conditions. The results of computations show that the types of the test functions do not influence on the accuracy. In contrast, the weight functions for the moving least square approximation should not be chosen as trial functions to ensure the accuracy. Furthermore, the influence of choosing the ways for imposing essential boundary conditions on the accuracy was not detected

A lysimeter experiment was carried out over 3 years to clarify efficient use of anaerobically digested cattle slurry (ADCS) produced from a biogas plant on the basis of the efficiency of its nitrogen (N). Timothy (Phleum pratense L.) was the test crop, with ADCS applied at different rates and times. Nitrogen uptake by the grass varied from 18 to 30% of total N (T-N) in the ADCS, with spring application (late April) increasing efficiency compared to autumn application (late October). Ammonia N (NH3-N) volatilization was around 13% of the ADCS T-N, irrespective of application rate and time. Nitrogen leaching, of which the major form was nitrate N (NO3-N), ranged from 6 to 12% of ADCS T-N. The lowest leaching loss was associated with the standard rate of spring application, giving a total of 32 g m− 2 (320 kg ha− 1) in 3 years as ammonium N (NH4-N) derived from the ADCS. Nitrous oxide N (N2O-N) emission loss from the soil amounted to less than 0.1% of ADCS T-N. The standard rate of spring application of the ADCS gave the maximum N use efficiency (for dry matter production) of the ADCS and the minimum N loss. We concluded, under the experimental conditions, that the standard rate ADCS application, in early spring, gave the highest N efficiency in grass dry matter production, and reduced environmental risks.

Microforceps that can be used with the hyper utility mechatronic assistant system (HUMAN) for bipolar coagulation in minimally invasive neurosurgery were developed. A method of using two sets of those forceps for bipolar coagulation was developed, in which electrical current is passed through the drive wires to the forceps tips to form an electrical circuit. A prototype mechanism that employs a torque tube to achieve an opening and closing speed of 138/spl deg//s was fabricated. A forceps drive system that has a delay time of 0.06 s was constructed by using a fast control algorithm. In vivo experiments on rat abdomen and rat brain blood vessels confirmed that the bipolar coagulation function is of a practical level. Three neurosurgical clinicians confirmed the good operability and practicality of the gripping function in experiments on a human cadaveric brain. Furthermore, both doctors and engineers confirmed that the microforceps described here can be used in their present form in tumor removal and other such procedures. Following these basic engineering experiments, basic medical experiments (including experiments on the optimum distance between the lens of the endoscope and, the object of manipulation), various surgical procedures performed on living rat brain, surgical simulations performed on a human cadaver, and experiments on safety in ethylene oxide gas sterilization were performed. They lead to the conclusion that clinical use of the HUMAN system is feasible.

In this paper, we review the detailed study of epitaxial growth of β-FeSi 2 films by reactive deposition epitaxy (RDE), multilayer technique and molecular beam epitaxy (MBE). The p - and n -type β-FeSi 2 was formed when it was grown under an Fe-rich and an Si-rich condition, respectively. The maximum electron and hole mobilities of the β-FeSi 2 epitaxial films reached 6900 and 13000 cm 2 /V·s for the n - and p -type β-FeSi 2 , respectively, at around 50 K. Room temperature (RT) 1.6 μm electroluminescence (EL) was realized by optimizing the growth conditions for p -Si/β-FeSi 2 particles/ n -Si structures prepared by RDE for β-FeSi 2 and by MBE for Si.

The carrier density of highly [100]-oriented β- FeSi 2 films grown by molecular beam epitaxy (MBE) was smaller than that by the multilayer method. For the MBE grown, undoped n- and p-type β- FeSi 2 films, only one donor (E D1 = 0.21 eV) and one acceptor (E A2 = 0.11 eV) levels were obtained from the temperature dependence of the carrier density, in contrast with the fact that two kinds of donor (E D1 = 0.21 eV and E D2 = 0.08 eV) and acceptor (E A1 = 0.19 eV and E A2 = 0.11 eV) levels were obtained for layers grown by multi-layer method. These results suggest that the decrease of the carrier density in the MBE-grown films is due to disappearance of the E D2 or E A1 level.

Summary 1 This paper describes the germination mechanism of hard seeds of a species of honey locust, Gleditsia japonica, which can germinate only when externally damaged, in relation to four germinating factors: feeding damage by two specialist seed predators, a bean weevil (Bruchidius dorsalis) and a cydid bug (Adrisa magna); feeding damage by a generalist seed predator, a wild mouse (Apodemus speciosus); and physical damage. 2 In laboratory experiments, both the bean weevil and physical damage facilitated germination, while damage by the cydid bug and wild mouse did not. 3 In contrast to laboratory findings, field censuses of G. japonica seed survival revealed that more than 99% were damaged either by B. dorsalis or A. magna. Therefore, less than 0·5% of the seeds remained intact, preventing formation of a seed bank. 4 In addition, all germinating seeds found in the field contained B. dorsalis larvae. 5 These results strongly suggest that damage by B. dorsalis is a prerequisite for G. japonica germination, in contrast to the conventional view that physical disturbance, possibly flooding, is the primary germinating factor for hard seeds.

We fabricated single-crystalline β-FeSi2 balls with various sizes embedded in Si crystals by reactive deposition epitaxy (RDE) and following molecular beam epitaxy (MBE). The photoluminescence (PL) depended on the size of the β-FeSi2 ball. We observed clear 1.54 μm PL from the sample with approximately 100-nm diameter β-FeSi2 balls, but not from the sample with the balls of approximately 150 nm in diameter or bigger. It was found from deep level transient spectroscopy (DLTS) measurements that absence of the 1.54-μm PL emission was attributed to the existence of deep levels in the Si crystals around the β-FeSi2 balls.

Object. The purpose of this study was the analysis of a large series of patients treated with gamma knife radiosurgery for pituitary adenoma in a single institution. Methods. One hundred eight patients with pituitary adenomas were treated over the last 7 years. Seventy-four patients have been followed for more than 6 months and form the basis of this report. Conclusions. Twenty-three patients harbored nonfunctioning adenomas, and 56 harbored functioning adenomas. The mean margin dose was 22.5 Gy (nonfunctioning adenomas, 19.5 Gy; functioning adenomas, 23.8 Gy). Control of tumor growth was achieved in 91%. A significant decrease of excessive hormone production was seen in 80% of patients, and the endocrinological normalization rate was 30.3%. Postradiosurgical complications were seen in 2.5%.

We previously reported that the coagulation system in cerebrospinal fluid (CSF) is strongly activated in the early stage of a subarachnoid haemorrhage (SAH). We evaluated the relationship among thrombin activity, degree of SAH, amount of clearance of SAH, and vasospasm. The CSF levels of fibrinopeptide A (FPA) were measured by radio-immunoassay in 36 SAH patients, who were diagnosed by computerized tomography (CT) within 12 hours and on whom surgery was performed within 48 hours. Clearance of SAH (%) was evaluated as the size of the clot in the basal cistern visualized between the initial and postoperative CT. The mean level of FPA in the patients of Group 3 (Fisher's CT classification) (182.2 ng/ml) was significantly higher than those in the patients of Group 2 (36.2 ng/ml). There was a significant difference in the mean level of FPA between patients with (47.6 ng/ml) and without infarction (408.3 ng/ml). In 18 of the 27 patients of Group 3 for whom the clearance of the SAH was determined, the patients showing a lower clearance rate (50%) of SAH demonstrated a significantly higher rate of infarction and a significantly higher level of FPA (466.6 ng/ml) than did the patients with a higher clearance rate (50%) of SAH (79.2 ng/ml). These results suggest that, the thrombin activity in CSF is correlated with the degree of SAH, the persistence of subarachnoid clot and the development of vasospasm.

RESUMO – Este trabalho tem como objetivo simular o craqueamento termico de oleo de canola. O simulador utilizado foi o Aspen HYSYS. O mecanismo de reacao de craqueamento adotado, de acordo com a literatura, consiste em cinco etapas distintas: decomposicao dos triglicerideos, decomposicao dos acidos graxos, decomposicao do cetano e da acroleina, formacao do coque e formacao do produto final. As condicoes operacionais utilizadas foram: temperatura de 400 °C e pressao 1 atm, escolhidas com base em dados de literatura. Utilizou-se oleo de canola como materia-prima para as reacoes, cujos produtos sao OLP (Produto orgânico liquido), gas e oleo residual. Os resultados da simulacao foram analisados e comparados com os dados disponiveis na literatura.

Gallium oxide (Ga2O3) films are prepared by RF magnetron sputtering at room temperature. Structural and optical properties of the films with different thickness are studied before and after annealing. An increase in surface roughness due to grain size growing is observed on annealed films. However, optical transmittance in infrared to ultra violet region was kept at above 80% regardless of the rough surface morphology.

Storage characteristics of KCl:Eu2+ phosphor were investigated in order to apply the phosphor to wide-range neutron detection. For detection of both slow and fast neutrons, 6LiF powders and polyethylene powders were added to the phosphor at the same time. The optimization of the phosphor for maximum photostimulated luminescence yields have been performed and obtained at a polyethylene weight ratio of about 0.05 when the mixtures were irradiated by fast neutron with energy of 14.8 MeV, where the weight ratio of KCl:Eu2+ phosphor to 6LiF powders was fixed to be two to three. These experimental results well agreed with theoretical predictions by Monte Carlo simulation using PHITS code. The energy deposition by slow or intermediate neutrons was mainly due to charged particles as a result of nuclear reaction of 6Li(n,α)T. According to relativistic calculation, the energy of alpha particles or tritons cannot be uniquely determined in a laboratory system but has a certain distribution even if incident neutron energy is fixed when neutron energy is high. The calculation showed that charged particles produced by nuclear reactions such as 39K(n,α) or 35Cl(n,α), in addition to protons by 1H(n,n)1H reaction, will contribute the total energy deposition at high energy of incident neutrons.

[1 0 0]-oriented β -FeSi 2 films were grown on Si(0 0 1) substrates by molecular beam epitaxy (MBE) with a deposited Si to Fe atomic ratio (Si/Fe ratio) varied from 1.6 to 2.8. It was found that the conduction type of the β -FeSi 2 films changed from p- to n-type between the deposited Si/Fe=2.4 and 2.8. Rutherford Back Scattering (RBS) measurements revealed that the real Si/Fe ratio of β -FeSi 2 is 2.0–2.1 for all the samples after 900°C annealing for 14 h, showing that stoichiometry of the grown films is almost satisfied even though the deposited Si/Fe ratio was away from stoichiometry.

Storage characteristics of mixtures of polyethylene powder and photostimulable phosphors such as KCI:EuH with low gamma-ray sensitivity were investigated in order to improve the spatial resolution when the mixtures were applied to fast neutron imaging. The maximum photostimulated luminescence yields were obtained at a KCI:EuH weight ratio of about 0.8 when the mixtures were irradiated by fast neutron with an energy of 14.8 MeV. These experimental results well agreed with theoretical predictions by Monte Carlo simulation using PHITS code. Estimated spatial resolution of the optimal mixture sample was 0.068 mm that was better than that obtained by conventional methods where the radiators are set in front of the phosphors. These mixtures will be usable for fast neutron imaging.

A method for multiresidue analysis of 48 pesticides (20 organophosphorus pesticides, 7 organochlorine pesticides, 14 organonitrogen pesticides, and 7 pyrethroid pesticides) permitted in Japan was systematically developed on the basis of capillary GC. Pesticides were simultaneously extracted with acetone from vegetable and fruit samples or with acetonitrile from lipid-containing crops and then re-extracted into ethyl acetate (test solution). Pesticides in the test solution were determined by capillary GC: Organophosphorus pesticides were directly determined by FPD-GC. Organonitrogen pesticides were determined by FTD-GC (NPD-GC) following cleanup by silica gel chromatography

Recently, a, number of studies on the 3-D reconstruction of the ultrasound echography are described and published. 3-D Ultrasound echography, compared with other three dimensional medical images, e. g., MR(magnetic resonance)imaging, computed tomography(CT)and positron emission tomography(PET), is effective as an intraoperative use. However, the reconstruction requires computational power and that makes this study not applied to the sufficient clinical use. The authors developed a compact, mobile and less costly ultrasound computer reconstruction system for stereotactic neurosurgery. The system consists of sector probe(Aloka, 20mm in diameter)actuator for its rotation, ultrasound imaging system and personal computer for reconstruction. The probe is guided through a burr hole and automatically rotates in half circle and images gained among this movement are transferred to the personal computer. Then the computer reconstructs the four transverse images and displays on the extension monitor. With the us age of this system, the operator can obtain an ultrasound image on planes perpendicular to a trajectory; they are effective as an guidance for the surgical operation. Computational time scale is enough short(20 sec.)for the usage during the operation. The most attractive feature is that the cost is lower because the system needs only existing ultrasound imaging system and personal computer.

The c-kit proto-oncogene encodes a transmembrane tyrosine kinase receptor and is shown to be allelic with the white-spotting locus (W) of the mouse. In order to elucidate the role of c-kit protein during placental development, we have examined the expression of c-kit protein in the uterus and placenta of mice at pre- and post-implantation stages by the avidin-biotin-peroxidase (ABC) method using rat anti-mouse c-kit monoclonal antibody. At Days 3 and 5 of pregnancy and pseudo-pregnancy, c-kit protein was detected in the glandular epithelium, but little expression was observed in the luminal epithelium. At Day 7 of pregnancy, expression was detected in the stromal cells around the uterine crypts of the mesometrial portion, but not in the vigorously proliferating decidual cells around the developing embryo. At Days 9 and 10 of pregnancy, the decidua basalis facing invading trophoblasts gradually expressed c-kit protein. In the mature placenta, c-kit protein was detected in the labyrinthine and decidual layers, but in neither the giant trophoblastic nor the spongiotrophoblastic layer. By Northern blotting and reverse transcriptase-polymerase chain reaction (RT-PCR), c-kit mRNA was detected at the stages of periimplantation and placental development. These results suggested that the c-kit protein might be involved in the proliferation and differentiation of placenta.

With specific monoclonal antibodies, we found that human endomethal stromal cells and decidual cells express two functionrelated surface antigens. Indirect immunofluorescence staining revealed that both endometrial stromal cells and decidual cells during the first trimester of pregnancy expressed cluster of differentiation (CD) 13 antigen and CD1O antigen, which are identical to aminopeptidase N and neutral endopeptidase, respectively. By flow cytometric analysis, CD1 3 antigen was detected on 8293% of the examined cells, and CD1O antigen was detected on 75-93% of the examined cells in endometrial stromal cellenriched preparations. Furthermore, peptidase activity was detected in these cell preparations by an assay based on the hydrolysis of alanine-p-nitroanilide into p-nitroaniline and alanine.

INTRODUCTIONGuest Editor's Introduction: The most specific adsorption of antibody can be achieved by the application of antigen-antibody binding. The antibody is specific for a particular part of antigen called epitope rather than for the whole antigen molecules. Therefore, the immobilized epitope for target antibody could be used as the ligand of the adsorbent. Kuraray Co. developed a specific adsorbent for the anti-acetylcholine receptor antibody. The adsorbent consists of microporous cellulose beads for the base material which immobilized a synthetic peptide as the epitope ligand. This paper describes the basic design and in vitro characteristics of the adsorbent. This paper was printed in Therapeutic Plasmapheresis, vol 12, page 573–576 (1993), and reprinted here with permission.

INTRODUCTIONGuest Editor's Introduction: This paper was presented at the fourth congress of the Japanese Society for Therapeutic Plasmapheresis in Tokyo, Japan, on June 2, 1984. The paper was printed in Therapeutic Plasmapheresis (proceedings of the fourth congress), edited by T. Oda and published by Schattauer, Stuggart, in 1985, p. 45–49. This paper provides the first technical description of plasma fractionators for cascade filtration. EVAL (ethylenevinyl alcohol copolymer) hollow fibers of different porosities (four types) were utilized for various macromolecular separations. Two types of EVAL secondary filters are described in this article. Successful cascade filtrations were expected to be performed with these filters.

Storage characteristics of KBr:Eu2+ phosphor were investigated when the phosphor was irradiated by fast neutron with energy of 14.8 MeV. To improve the fast neutron sensitivity, polyethylene (PE) sheets as a proton generator were set in front of the phosphors. The maximum photostimulated luminescence (PSL) yields were obtained at a PE thickness of about 3 mm. These experimental results well agreed with those by Monte Carlo simulation using PHITS code. Estimated PSL yields by gamma-ray associated with fast neutron fields were negligible. This combination use of such phosphors and PE sheets will be usable for fast neutron monitoring or imaging in a high gammaray field.

Human decidua of early pregnancy contains considerable numbers of CD3-CD56+ natural killer (NK) cells. In this study, two major protein products of the decidua, placental protein 14 (PP14) and placental protein 12 (PP12), were tested for the ability to regulate human NK cell activity. In vitro overnight exposure to PP14 of blood lymphocytes or purified large granular lymphocytes (LGL) resulted in suppression of cytotoxicity against K562 target cells in a 4-h 51Cr release assay. The NK inhibition was dependent on concentrations of PP14, being detectable at 5 micrograms/ml and reaching maximum at 50 micrograms/ml. Manifestation of PP14-induced NK suppression required 18-h contact with NK cells. The suppression of NK activity by PP14 was not abolished by indomethacin. In a target binding assay the number of PP14-treated LGL binding to K562 was comparable to that of untreated ones. By contrast with PP14, PP12 produced no effects on NK cells. These results indicate that PP14 suppresses the function of NK cells, which might be involved in prevention of maternal immune rejection of fetus at the fetomaternal interface.

Although some studies have indicated that endometriosis may increase the risk of developing ovarian cancer, there are no data from epidemiologic studies in Japan. We prospectively analyzed all cases of ovarian endometrioma enrolled in the prefecture-wide Shizuoka Cohort Study on Endometriosis and Ovarian Cancer Programme, which was initiated in 1985. To evaluate the risk of ovarian cancer by time periods subsequent to ovarian endometrioma diagnosis, a cohort of 6,398 women with a clinically documented ovarian endometrioma in Shizuoka between 1985 and 1995 was identified from the Shizuoka Cancer Registry (SCR), with follow-up through 2002. Ovarian cancer incidence among cohort members was ascertained by linkage to the SCR using a unique person-identification number. Standardized incidence ratios (SIR) and their 95% confidence intervals (CI) were computed by a use of prefecture-wide rates of ovarian cancer, adjusted for age and calendar year. During follow-up of up to 17 years of the ovarian endometrioma cohort, 46 incident ovarian cancers were identified, yielding that the ovarian cancer risk was elevated significantly among patients with ovarian endometrioma (SIR = 8.95, 95% CI = 4.12–15.3). The SIR did not increase with increasing follow-up duration. The risk increased with increasing age at ovarian endometrioma diagnosis, with a SIR equal to 13.2 (95% CI = 6.90–20.9) in women above 50 years of age. Our findings for the first time support the hypothesis that ovarian endometrioma increases the subsequent risk of developing ovarian cancer in Shizuoka, Japan

Radical resection of gliomas can increase patient's survival. There is known concern, however, that aggressive tumour removal can result in neurological morbidity. The objective of the present study was to evaluate the usefulness of low magnetic field strength (0.3 Tesla) open intraoperative magnetic resonance imaging (iMRI) for complete resection of glioma with emphasis on functional outcome.From 2000 to 2004, 96 patients with intracranial gliomas underwent tumour resection with the use of iMRI in Tokyo Women's Medical University. There were 50 men and 46 women; mean age was 39 years. Tumour volume varied from 1.2 ml to 198 ml (median: 36.5 mL). Resection rate and postoperative neurological status were compared between control group (46 cases, operated on during the initial period after installation of iMRI), and study group (50 most recent cases, in whom surgery was done using established treatment algorithm and improved image quality).Overall, mean resection rate was 93%, and medial residual tumour volume was 0.17 ml. Total tumour removal was achieved in 44 cases (46%). Compared to control group, resection rate in the study group was significantly higher (91%, vs. 95%; P0.05), whereas residual tumour volume was significantly smaller (1.7 mL vs. 0.025 mL; P0.001). Nine patients in the control group (20%) and 24 in the study group (48%) experienced temporary postoperative neurological deterioration (P0.01), however, the rate of permanent morbidity evaluated 3 months after surgery did not differ significantly between the groups investigated (13% vs. 14%).Use of iMRI during surgery for intracranial gliomas permits to attain aggressive tumour resection with good functional outcome. Nevertheless, surgical experience with the iMRI system, establishment of treatment algorithm, and improvement of image quality are of paramount importance for optimal results.

Gamma Knife surgery (GKS) is a minimally invasive treatment for brain diseases, and is currently used for functional disorders. Moreover, a revised version of Gamma Knife system, ‘Model C-APS (automatic positioning system)’ started to be installed in Japan since 2001. This latest model enables us to adjust coordinates by every 0.1 mm, and treat the patient automatically. We have completed a retrospective study of 222 patients suffering from essential trigeminal neuralgia treated with GKS in which the target was localized at the retro-gasserian portion of the nerve (We have treated 179 patients with essential trigeminal neuralgia by ‘Model C-APS’). Among the patients, 147 were followed up more than 12 months, and we evaluated a cause-and-effect relationship between the technical development and the clinical results. We categorized patients into three groups based on the term mentioned as follows: first are the patients treated by Model B without completed fusion images in between 1999 and 2001, second are the patients treated by Model B with completed fusion images in 2002, and third are those treated by model C-APS with completed fusion images since 2003. Clinical result, initial pain free was observed in 62.9% (first group), 85.7% (second group), 98.1% (third group), complete recurrence was observed in 12, 8.3, 1.9% for each groups, and postoperative complication was observed in 22.2, 28.6, and 23.6% respectively. We believe that precise dose planning, so-called ‘Robotized Micro Radiosurgery’, is the key to have a successful GKS.

Rationale: Currently, one of represented severe pain, cancer pain related to bone metastasis, has been able to be controlled well using Gamma Knife pituitary radiosurgery (GKPR) without any signific

Rationale: Up until two or three decades ago, cancer pain had been treated with surgical/chemical hypophysectomy, and there was a report that central pain (thalamic pain syndrome) had also been tried to be controlled with chemical hypophysectomy. The clinical results showed that hypophysectomy provided most of the patients relief from severe pain. However, severe accompanying adverse effects (panhypopituitarism, diabetes insipidus, and visual dysfunction) were found in almost all patients. This historical evidence prompted us to perform gamma knife surgery (GKS) for control of this kind of severe intractable pain with a high irradiation dose to the pituitary stalk/gland as an alternative hypophysectomy. This method has provided the majority of patients relief from severe pain, and surprisingly without any of the above-mentioned complications. Material and Methods: We have been carrying out a prospective collaborative study in Prague, Hong Kong, and our institute (Tokyo) for this treatment to evaluate the efficacy and safety of this method. Indications for this treatment are: (1) no other effective treatment prior to GKS; (2) general condition is considered good (KPS > 40%); (3) morphine is effective for pain control (for cancer pain), and (4) no previous treatment with radiation (GKS/conventional radiotherapy) for brain metastasis. In our institutional experience, in Tokyo, we have treated 10 patients who suffered from severe cancer pain due to bone metastasis with GKS, and 15 patients who suffered from post-stroke thalamic pain syndrome. The target was just the border in between the pituitary stalk and gland. Maximum dose was 160 Gy for cancer pain and 140 Gy for central pain. We could follow up all patients (>1 month) with cancer pain and 8 patients (>6months) with thalamic pain syndrome. Results: All patients (10/10) with cancer pain experienced significant pain reduction, and 87.5% (7/8) of the cases with thalamic pain syndrome initially experienced significant pain reduction. Some of patients felt reduced pain within several hours. Pain reduction was apparent within 7 days (median 2 days). No recurrence was observed in the patients with cancer pain; on the other hand, real recurrence was seen in 71.4% (5/7) of the cases with thalamic pain syndrome over 6 months of follow-up. No other complication has been observed in any of the cases up to now. Conclusions: Our clinical study protocol is not mandatory and still insufficient. In particular, much more investigation for clinical results of GKS in patients with thalamic pain syndrome is needed to optimize this treatment protocol. However, efficacy and safety have been shown in all of our cases. We believe that this treatment has a potential to control severe pain well, and that GKS plays a very important role in the field of intractable pain management.

We investigate trajectory planning for a time minimizing task in human reaching movements. Using computer simulation, we found that the minimum movement-time trajectory is considerably concave toward a body and its velocity profile has two peaks. In psychophysical experiments, we observed that the subjects generated roughly straight hand paths with bell-shaped velocity profiles in the time-minimizing task. These features can be reproduced by the minimum commanded torque change criterion that requires the smoothness of motor command. We confirmed that the subjects could generate minimum movement-time trajectories when given a via-point and some instructions. The experimental results suggest that the brain cannot calculate the optimal trajectory according to the performance index except for the smoothness.

Information-guided stereotaxis, assisted by visualization of medical information, will become the next generation of neurosurgical systems. We performed 76 open MRI surgeries at Tokyo Women's Medical University between March 3, 2000 and April 12, 2001. Of them, comparisons of pre- and post-operative MR images for malignant gliomas in 21 cases revealed an average resection rate of 90.3% (the maximum 100%, the minimum 55%). In this article we describe real time updated navigation, augmented reality navigation, three-dimensional navigation, chemical navigation, information-guided navigation system (High definition visual Computer Aided Surgery System: HivisCAS), and open MRI-guided surgery that we are developing.