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Background/Aims: To identify the clinical characteristics of polypoidal choroidal vasculopathy (PCV) in Caucasian patients and assess the prevalence of anti-vascular endothelial growth factor (anti-VEGF) resistance. Methods: This involved a retrospective chart review of Caucasian patients diagnosed with PCV and utilizing indocyanine green angiography with the scanning laser ophthalmoscope. Data collected included patients’ demographics, disease characteristics, and treatment response. Results: There were 54 eyes of 49 patients with PCV; 51.0% were male and 49.0% were female with a mean age of 72.9 years. Forty-four patients (89.8%) had PCV unilaterally and 10.2% (5 patients) had PCV bilaterally. PCV was located in the macula in 79.6%, in the peripapillary region in 16.7%, and in both regions in 3.7%. PCV commonly presents with serous detachment (66.7%), retinal pigment epithelial detachment (RPED) (51.9%) and subretinal hemorrhage (37.0%). Twenty-nine eyes were included in the treatment response analysis, with 18 eyes (62.1%) showing persistent disease activity after 3 initial injections of anti-VEGF treatment. Conclusion: PCV in Caucasian patients is more often unilateral and presents more commonly in the macular region than the peripapillary region. Serous detachment and RPED are the 2 most common findings. Resistance to current anti-VEGF treatment was noted frequently; it is thus extremely important to identify this subtype of type I subretinal neovascularization.

Purpose To evaluate the prevalence of polypoidal choroidal vasculopathy (PCV) in different ethnic populations and to determine the prevalence of PCV in eyes with exudative age-related macular degeneration (AMD) that is sensitive and resistant to anti–vascular endothelial growth factor (VEGF) therapy. Design Retrospective chart review. Participants Two hundred fifty-three eyes of 221 patients with exudative AMD. Methods Baseline data were collected on all eyes diagnosed with exudative AMD, which included ethnic data. Polypoidal choroidal vasculopathy was diagnosed using indocyanine green angiography (ICGA) with the scanning laser ophthalmoscope. Exudative AMD eyes were separated into 2 groups: anti-VEGF–resistant eyes with persistent subretinal fluid, subretinal hemorrhage, or macular edema after 4 anti-VEGF injections and anti-VEGF–sensitive eyes defined as eyes without residual disease activity. The prevalence of PCV was determined in each group based on ICGA. Main Outcome Measures Prevalence of PCV in exudative AMD, and in different ethnic populations, and prevalence of anti-VEGF resistance in eyes with and without PCV. Results Exudative AMD was diagnosed in 253 eyes of 221 patients. Polypoidal choroidal vasculopathy was noted to have a prevalence of 45.1% (114/253 eyes) in the overall population. Polypoidal choroidal vasculopathy was noted in 51.6% (81/157) of eyes with wet AMD in Asians, 31.9% (23/72 eyes) of eyes with wet AMD in white persons, and 28.6% (4/14 eyes) in a small group of Pacific Islanders. Polypoidal choroidal vasculopathy was diagnosed in 50% (60/120 eyes) of eyes in the anti-VEGF–resistant group, which is more prevalent than the 30.2% (29/96 eyes) in the anti-VEGF–sensitive group (P Conclusions Polypoidal choroidal vasculopathy is more prevalent in Asian patients with exudative AMD, but is more prevalent than generally recognized in white patients. Polypoidal choroidal vasculopathy is more prevalent in anti-VEGF–resistant eyes in both white and Asian patients, which could help to predict therapeutic response.

Determine sensitivity and specificity of polypoidal choroidal vasculopathy (PCV) diagnosis with structural en face optical coherence tomography (OCT) and OCT angiography (OCTA).Retrospective review of the medical records of eyes diagnosed with PCV by indocyanine green angiography with review of diagnostic testing with structural en face OCT and OCTA by a trained reader. Structural en face OCT, cross-sectional OCT angiograms alone, and OCTA in its entirety were reviewed blinded to the findings of indocyanine green angiography and each other to determine if they could demonstrate the PCV complex. Sensitivity and specificity of PCV diagnosis was determined for each imaging technique using indocyanine green angiography as the ground truth.Sensitivity and specificity of structural en face OCT were 30.0% and 85.7%, of OCT angiograms alone were 26.8% and 96.8%, and of the entire OCTA were 43.9% and 87.1%, respectively. Sensitivity and specificity were improved for OCT angiograms and OCTA when looking at images taken within 1 month of PCV diagnosis.Sensitivity of detecting PCV was low using structural en face OCT and OCTA but specificity was high. Indocyanine green angiography remains the gold standard for PCV detection.

Robotic interventional neuroradiology is an emerging field with the potential to enhance patient safety, reduce occupational hazards, and expand systems of care. Endovascular robots allow the operator to precisely control guidewires and catheters from a lead-shielded cockpit located several feet (or potentially hundreds of miles) from the patient. This has opened up the possibility of expanding telestroke networks to patients without access to life-saving procedures such as stroke thrombectomy and cerebral aneurysm occlusion by highly-experienced physicians. The prototype machines, first developed in the early 2000s, have evolved into machines capable of a broad range of techniques, while incorporating newly automated maneuvers and safety algorithms. In recent years, preliminary clinical research has been published demonstrating the safety and feasibility of the technology in cerebral angiography and intracranial intervention. The next step is to conduct larger, multisite, prospective studies to assess generalizability and, ultimately, improve patient outcomes in neurovascular disease.

We have fabricated $129\ \mathrm{k}\Omega$ and $1\ \mathrm{M}\Omega$ quantum Hall array devices using GaAs/AlGaAs heterostructures and their quantized Hall resistance plateaus were precisely evaluated with an accuracy of better than $5\times 10^{-8}$ based on NIST's quantized Hall resistance standard via stable standard resistors. These higher quantized values have been attracting industrial interests for applications such as precise small electric power (small current) measurements, leakage current, and electrical insulation measurements. Given these quantum Hall array devices, an accuracy of better than $1\times 10^{-7}$ for $1\ \mathrm{M}\Omega$ resistance standard measurements will be achieved, through a simple cryogenic quantum Wheatstone bridge technique. These devices could also be utilized for a quantum voltage divider.

To investigate olfactory function in elderly subjects requiring nursing care to clarify its association with appetite and nutritional status. Facility for the elderly requiring nursing care. Participants: The subjects were 158 elderly people requiring nursing care and 37 elderly people not requiring nursing care. Experiment I: Olfactory function and factors (cognitive function, appetite, and nutritional status) that may be associated with it were compared between the elderly subjects requiring nursing care and those not requiring nursing care using covariance analysis in consideration of age. For evaluation, the OSIT-J was used for olfactory function, the HDS-R for cognitive function, the CNAQ for appetite, and BMI for nutritional status. Experiment II: The subjects were the same elderly subjects requiring nursing care in Experiment I, and food intake was surveyed in addition to the OSIT-J, HDS-R, CNAQ, and BMI. A univariate linear regression analysis was performed with OSIT-J as the response variable, and age, HDS-R, CNAQ, BMI, and food intake as the explanatory variables. Experiment I: On covariance analysis, the OSIT-J score was significantly lower for the elderly subjects requiring nursing care than for those not requiring nursing care (p

• PURPOSE: To assess the long-term stability of sutured scleral-fixated posterior chamber intraocular lenses (PCIOLs) performed in combination with pars plana vitrectomy. • DESIGN: Retrospective, consecutive, interventional case series. • METHODS: Retrospective single-surgeon study of 118 eyes of 111 patients seen at Retina Consultants of Hawaii, who underwent sutured scleral fixation of at least 1 haptic of a posterior chamber intraocular lens with 10–0 polypropylene combined with a pars plana vitrectomy. The fixation knot-tying technique required 2 separate 10–0 polypropylene sutures tied into 1 combined knot—1 suture closed the fixation sclerotomy and created the scleral fixation, and 1 suture looped together around the haptic of the PCIOL, securing the haptic to the scleral fixation site. The primary outcomes were position of the PCIOL at last follow-up, dislocation of either 1 or both haptics of the PCIOL, and breakage of the 10–0 polypropylene fixation suture. • RESULTS: PCIOLs remained well stabilized and positioned at last follow-up in 116 of 118 eyes (98.3%), with a mean follow-up of 6.0 years. The maximum stable follow-up with 2 intact fixation sutures was 24.75 years. There were 4 cases of redislocation (3.4%), but 2 cases were owing to unstable residual capsular support. There was 1 case of suture breakage in 214 fixation sutures (0.47%) and 1 case of haptic breakage. • CONCLUSIONS: Scleral fixation sutures with 10–0 polypropylene provide excellent long-term fixation of PCIOLs, with a less than 0.5% incidence of suture breakage and documented suture stability for up to 24+ years.

BIPM's new transportable programmable Josephson voltage standard (PJVS) has been used for an on-site comparison at the National Metrology Institute of Japan (NMIJ) and the National Institute of Advanced Industrial Science and Technology (AIST) (NMIJ/AIST, hereafter called just NMIJ unless otherwise noted). This is the first time that an array of niobium-based Josephson junctions with amorphous niobium silicon Nb x Si1−x barriers, developed by the National Institute of Standards and Technology4 (NIST), has been directly compared to an array of niobium nitride (NbN)-based junctions (developed by the NMIJ in collaboration with the Nanoelectronics Research Institute (NeRI), AIST). Nominally identical voltages produced by both systems agreed within 5 parts in 1012 (0.05 nV at 10 V) with a combined relative uncertainty of 7.9 × 10−11 (0.79 nV). The low side of the NMIJ apparatus is, by design, referred to the ground potential. An analysis of the systematic errors due to the leakage current to ground was conducted for this ground configuration. The influence of a multi-stage low-pass filter installed at the output measurement leads of the NMIJ primary standard was also investigated. The number of capacitances in parallel in the filter and their insulation resistance have a direct impact on the amplitude of the systematic voltage error introduced by the leakage current, even if the current does not necessarily return to ground. The filtering of the output of the PJVS voltage leads has the positive consequence of protecting the array from external sources of noise. Current noise, when coupled to the array, reduces the width or current range of the quantized voltage steps. The voltage error induced by the leakage current in the filter is an order of magnitude larger than the voltage error in the absence of all filtering, even though the current range of steps is significantly decreased without filtering.

Background Reducing near‐fatal asthma exacerbations is a critical problem in asthma management. Objectives To determine patterns of factors preceding asthma exacerbations in a real‐world setting. Methods In a nationwide prospective study of 190 patients who had experienced near‐fatal asthma exacerbation, cluster analysis was performed using asthma symptoms over the 2‐week period before admission. Results Three distinct clusters of symptoms were defined employing the self‐reporting of a visual analogue scale. Cluster A (42.1%): rapid worsening within 7.4 hours from moderate attack to admission, young to middle‐aged patients with low Body mass index and tendency to depression who had stopped anti‐asthma medications, smoked, and hypersensitive to environmental triggers and furred pets. Cluster B (40.0%): fairly rapid worsening within 48 hours, mostly middle‐aged and older, relatively good inhaled corticosteroid (ICS) or ICS/long‐acting beta‐agonist (LABA) compliance, and low perception of dyspnea. Cluster C (17.9%): slow worsening over 10 days before admission, high perception of dyspnea, smokers, and chronic daily mild‐moderate symptoms. There were no differences in overuse of short‐acting beta‐agonists, baseline asthma severity, or outcomes after admission for patients in these 3 clusters. Conclusion To reduce severe or life‐threatening asthma exacerbation, personalized asthma management plans should be considered for each cluster. Improvement of ICS and ICS/LABA compliance and cessation of smoking are important in cluster A. To compensate for low perception of dyspnea, asthma monitoring of peak expiratory flow rate and/or exhaled nitric oxide would be useful for patients in cluster B. Avoidance of environmental triggers, increase usual therapy, or new anti‐type 2 response‐targeted therapies should be considered for cluster C.

Purpose: To retrospectively review the prevalence of myopia and elongated axial length in eyes with polypoidal choroidal vasculopathy (PCV) and to evaluate treatment response of PCV in highly myopic eyes. PCV has rarely been reported in myopic eyes. Methods: A retrospective review of all eyes diagnosed with PCV at the clinics of Retina Consultants of Hawaii and the Hawaii Macula and Retina Institute was performed between February of 2007 and April of 2017 to evaluate for eyes with significant myopia and elongated axial length. Results: A total of 282 eyes were diagnosed with PCV by ICG angiography. There were 144 males (59%) and 99 females (41%). 204 patients had unilateral PCV and 39 patients had bilateral PCV. A total of 3 patients with PCV had significant myopia less than -6 diopters or confirmed elongated axial length. One of these patients had bilateral PCV so there were 4 eyes noted with significant myopia and elongated axial length out of 282 eyes with PCV (1.4%). All 3 patients were Asian and presented with active leakage or bleeding related to PCV diagnosed on indocyanine green angiography and optical coherence tomography. Treatments typically used to treat PCV including intravitreal antiangiogenic medications and photodynamic therapy were utilized. Conclusion and Importance: High myopia is rare in eyes diagnosed with PCV, even though choroidal neovascularization is a common cause of vision loss in myopic macular degeneration. However, even in highly myopic eyes, PCV may show signs of resistance to antiangiogenic medications.

We report on our measurement of the Boltzmann constant by Johnson noise thermometry (JNT) using an integrated quantum voltage noise source (IQVNS) that is fully implemented with superconducting integrated circuit technology. The IQVNS generates calculable pseudo white noise voltages to calibrate the JNT system. Thermal noise of a sensing resistor placed at the temperature of the triple point of water was measured precisely by the IQVNS-based JNT. We accumulated data more than 400000 seconds in total and improved the method for the selection of the optimal measurement frequency range for the determination of the Boltzmann constant. Upon the detailed evaluation of the uncertainty components, the experimentally obtained Boltzmann constant was k=1.3806436×10^(-23) J/K with a relative combined uncertainty of 9.94 × 10^(-6).

Background A reduction in mortality with the early use of tranexamic acid has been demonstrated in severely injured patients who are bleeding. However, the modest treatment effect with no reduction in blood transfusion has raised concerns. The aim of the present study was to estimate the effectiveness of regular use of tranexamic acid in severely injured patients. Methods This multicentre observational study used retrospectively collected data from consecutive injured patients (Injury Severity Score at least 16) treated in 15 Japanese academic institutions in 2012. A propensity score-matched analysis compared patients who did or did not receive tranexamic acid administration within 3 h of injury. Study outcomes included 28-day all-cause and cause-specific mortality, and need for blood transfusion. Results Of 796 eligible subjects, 281 were treated with tranexamic acid. Propensity score matching selected a total of 500 matched subjects (250 in each group). Tranexamic acid administration was associated with lower 28-day mortality (10·0 versus 18·4 per cent; difference −8·4 (95 per cent c.i. –14·5 to −2·3) per cent) and lower 28-day mortality from primary brain injury (6·0 versus 13·2 per cent; difference −7·2 (−12·3 to −2·1) per cent). However, there was no significant difference between groups in the need for blood transfusion (33·2 versus 34·8 per cent; difference −1·6 (−9·9 to 6·7) per cent). Conclusion Early tranexamic acid use was associated with reduced mortality in severely injured patients, in particular those with a primary brain injury.

Introduction L’efficacite et la tolerance du mepolizumab dans ASE etant bien etablies, COMET a examine les resultats apres la poursuite ou l’arret du mepolizumab a long terme. Methodes COMET etait une etude multicentrique, randomisee, en double aveugle, controle par placebo. Les patients eligibles avaient complete COLUMBA/COSMEX, recu un traitement continu par mepolizumab pendant au moins 3 ans. Les patients ont ete randomises 1 :1 pour continuer mepolizumab 100 mg par voie SC toutes les 4 semaines pendant 52 semaines ou pour arreter mepolizumab. Les patients pouvaient revenir au traitement par mepolizumab en ouvert a la suite d’une exacerbation. Le critere primaire etait la duree jusqu’a la premiere exacerbation cliniquement significative. Les criteres secondaires etaient : la duree jusqu’a la diminution du controle de l’asthme ; la reduction de taux d’eosinophiles sanguins. Les criteres ont ete analyses en utilisant le modele des risques proportionnels de Cox et des modeles repetes de modele mixte ajustes pour les covariables. Resultats Cent quarante-quatre patients ont recu mepolizumab et 151 placebo. Quarante-six pour cent (66/144) patients ayant continue mepolizumab versus 59 % (89/151) patients ayant arrete mepolizumab ont eu une exacerbation. Les patients ayant continue versus ceux ayant arrete mepolizumab ont eu une duree plus longue jusqu’a la premiere exacerbation (HR : 0,62 [(IC)95 % : 0,45 ; 0,86] ; p = 0,004) et une duree significativement plus longue jusqu’a la diminution du controle de l’asthme (HR : 0,66 [0,49 ; 0,88] ; p =0,005), sans difference entre les traitements pour la duree jusqu’a la premiere exacerbation necessitant une venue aux urgences ou une consultation (HR : 1,33 [0,50 ; 3,51]). Les patients continuant mepolizumab ont maintenu leur taux d’eosinophiles entre 40 et 60 cellules/μL, les taux d’eosinophiles ont augmente jusqu’a 270 cellules/μL a la semaine 12 pour les patients ayant arrete mepolizumab (ratio : 0,19 [0,15 ; 0,24] ; p Conclusion Les patients ayant arrete mepolizumab ont presente une augmentation du taux d’eosinophiles sanguins, une augmentation des exacerbations, une duree plus courte jusqu’a la premiere exacerbation, et une reduction du controle de l’asthme compare a ceux ayant continue mepolizumab. Ces resultats montrent que le traitement continu par mepolizumab a des benefices cliniques durables chez la plupart des patients avec ASE.

Exotic surface states of topological insulators have long attracted the attention of researchers. Recently, surface-dominant electrical transport in topological insulators has been observed; however, surface conduction in topological insulators is still not fully understood. To address this knowledge gap, we measured the transport properties of a thin flake of a highly bulk-resistive topological insulator, Sn0.02Bi1.08Sb0.9Te2S (Sn-BSTS), whose carrier density was controlled with the field effect. Single crystals of Sn-BSTS were synthesized by the Bridgman method, and Hall devices were fabricated with exfoliated flakes. The bottom gate structure was used to control the bottom surface of a Sn-BSTS flake. The measured Hall resistance was analyzed using the two-band model, which quantitatively showed that ambipolar conduction was achieved. In addition, the carriers on the top surface were controlled by the formation of an electrical double layer by an ionic liquid. With a top-gate voltage of −1.5 V, a massive number of p-type carriers were induced on the top surface of the Sn-BSTS flake, as also confirmed with the two-band model. The longitudinal resistance was also found to be affected by the carrier density. The magnetoresistance was enhanced when n- and p-type carriers coexisted on the top and bottom surfaces. In particular, the magnetoresistance was quantitatively shown to increase when the densities of n- and p-type carriers were similar. This study is the first to quantitatively analyze the conduction in Sn-BSTS in the presence of multiple types of carriers. Our findings pave the way for a quantitative understanding of transport phenomena in topological insulators.

Among various methodologies of thermodynamic temperature measurements, Johnson noise thermometry (JNT) has an advantage that the structure and size of the temperature sensing probe are similar to conventional probes for contact thermometry. Another distinguishing feature is that the measurements are all electronic. Furthermore, the application of a quantum voltage noise source (QVNS), first introduced by the National Institute of Standards and Technology (NIST), has improved the accuracy of JNT during the past ten years. These developments have been driven under the rationale to determine the Boltzmann constant $$k$$ , in support of the proposed redefinition of the kelvin, and later to provide practical realization of the kelvin. At NMIJ, AIST, we have been developing a QVNS-based JNT system to first measure the Boltzmann constant and then aim to extend the temperature range to higher temperatures where $$T-T_{90}$$ data are lacking. An impact feature of our system is that most of our key elements have been built independently from NIST and the National Institute of Metrology, China (NIM); in particular that the Josephson junction array has been built in house at NeRI, AIST, and its driving method differs from that of either NIST or NIM. In this paper, the unique elements of the system as well as our initial results on the Boltzmann constant measurements are reported.

A Large-area charged particle detector for high energy physics experiments has been developed. This detector includes inorganic scintillation crystals and wavelength-shifting fibers. This enables us to detect charged particles with higher position resolution and lower cost than conventional scintillation detectors and gas chambers. It has an effective area of 1 m × 1 m.

BACKGROUND AND PURPOSE Reduced cardiac contractility has been associated with disrupted myocardial Ca2+ signalling. The 1,4 benzothiazepine K201 (JTV-519) acts on several Ca2+ handling proteins and improves cardiac contractility in vivo in a variety of animal models of myocardial dysfunction. However, it is unclear whether this improvement depends on the systemic effects of K201 or if K201 reverses the effects of Ca2+ dysregulation, regardless of the cause. EXPERIMENTAL APPROACH The effect of K201 on cardiac mechanical function was assessed in isolated working hearts from adult rabbits, using a ventricular pressure-volume catheter. In separate experiments, the effect of K201 was investigated in hearts following pharmacologically induced Ca2+ overload using elevated extracellular [Ca2+] ([Ca2+]o) and β-adrenoceptor stimulation. KEY RESULTS K201 induced a concentration-dependent decline in systolic function (peak pressure, dP/dtmax and preload recruitable stroke work), lusitropy (reduced dP/dtmin and increased end diastolic pressure) and stroke volume, independent of decreased heart rate. In separate experiments, mechanical function in hearts exposed to 4.5 mmol·L−1[Ca2+]o and 150 nmol·L−1 isoprenaline declined until cessation of aortic flow (in 6 out of 11 hearts). However, all hearts perfused with the addition of 1 µmol·L−1 K201 maintained aortic flow and demonstrated significantly improved peak systolic pressures, dP/dtmax and dP/dtmin. CONCLUSIONS AND IMPLICATIONS K201 significantly improved mechanical function of the heart during Ca2+ overload. This suggests that K201 can limit the detrimental effects of elevated intracellular Ca2+ and exert beneficial effects on cardiac contractile function, independent of systemic effects previously observed in vivo.

Direct microscopic methods using several fluorescent staining were applied to estimate the proportion of physiologically active bacteria in the water environment and evaluate the efficacy of disinfection with chlorine. 4′,6-diamidino-2-phenylindole (DAPI) was used to determine total bacterial numbers, and 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) was chosen for direct detection of respiring bacteria. BacLightTM kit was used to assess bacterial membrane integrity. Bacteria with growth potential were enumerated using the DVC method and microcolony technique. The total bacterial number in river was 8 × 106∼3 × 1010 cells/mL, and colony forming units on R2A medium were 1 × 104∼4 × 105 cfu/mL. In the case of wastewater treatment plant, 1 ∼ 10% of total bacterial cells could form colonies. Physiologically active bacteria in river and wastewater treatment plant determined by fluorescent staining were much higher than those obtained by plate counting. The effect of chlorine on the physiological viability of Escherichia coli was also investigated. Microscopic viable bacteria were even more chlorine resistant than culturable bacteria. The inactivation rate coefficients of direct viable bacteria were one-second to third those of culturable bacteria.

Using population pharmacokinetic analysis (PPK), we attempted to identify predictors of S-warfarin clearance (CL(S)) and to clarify population differences in S-warfarin pharmacokinetics among a cohort of 378 African American, Asian and white patients. Significant predictors of CL(S) included clinical (age, body weight and sex) and genotypic (CYP2C9*2,*3 and *8) factors, as well as African American ethnicity, the median CL(S) being 30% lower in the latter than in Asians and whites (170 versus 243 and 250 ml h-1, P

Inflammatory markers such as the C-reactive protein (CRP), white blood cell count and body temperature are easy to measure and are used as indicators of infection. The way in which they change in the early post-operative period after instrumented spinal surgery has not been reported in any depth. We measured these markers pre-operatively and at one, four, seven and 14 days postoperatively in 143 patients who had undergone an instrumented posterior lumbar interbody fusion. The CRP proved to be the only sensitive marker and had returned to its normal level in 48% of patients after 14 days. The CRP on day 7 was never higher than that on day 4. Age, gender, body temperature, operating time and blood loss were not related to the CRP level. A high CRP does not in itself suggest infection, but any increase after four days may presage infection.

We have studied the formation of Pd42.5Cu30Ni7.5P20 metallic glass droplets and wires in the gas atomization process. We demonstrate that the sizes of droplets and wires can be distinguished by the Ohnesorge number (Oh), which is the proportion of the spinnability to the capillary instability and the diameter distributions follow a log-normal distribution function, implying cascade fragmentation. For droplets, the number significantly increases at Oh Oh > 1 while the diameter steadies below 400 nm. Further, the wire diameter is quadrupled at Oh = 16 due to the high viscosity which suppresses both capillary breakup and ligament elongation.

We have developed a new PID detector consists of clear fibers. PID efficiency was measured with 470 MeV e + beam. As a result, this detector with thickness of 5 cm has the PID efficiency of 95 %.

We have been developing a submillimeter resolution and low-cost DOI-PET detector using wavelength shifting fibers (WLSF), scintillating crystal plates and MPPCs (Hamamatsu Photonics). Conventional design of DOI-PET detectors had approximately mm3 of resolution by using some scintillating blocks with a volume of 1 mm3, which detects gamma-ray. They are expensive due to difficulties in processing scintillating crystals and a large number of photo-detectors, and these technologies are likely to reach the limit of the resolution. Development of a lower cost DOI-PET detector with higher resolution is challenging to popularize the PET diagnosis. We propose two type of PET detector. One is a whole body PET system, and the other is a pet system for brain or small animals. Each PET system consists 6 blocks. The former consists of 6 layers of crystal plates with 300 mm × 300 mm × 4 mm. The latter consists of 16 crystal layers, forming 4 × 4 crystal arrays. The size of the crystal plate is 40 mm × 40 mm × 1 mm. Wavelength shifting fiber (WLSF) sheets are attatched to above and up and down side of crystal planes. The whole PET system has 8 MPPCs attached on each side. For the brain PET detector, 9 WLSF fibers are attached on the each side. The expected position resolution would be less than 1 mm at the former system. We have performed an experimental performance estimation for the system component using 22Na radioactive source. We achieved a collection efficiency of 10% using the WLSF sheet and Ce:Gd3(Al, Ga)5O12 (GAGG) crystals at 511 keV. The linear relationship between reconstruction position and incident position was obtained, and a resolution of 0.7 mm (FWHM) for x-axis of DOI by the WLSF readout was achieved.

We are developing the scintillation fiber trackers. This detector is consist of 0.5mm φ scintillation fibers and PPDs. This detector has the doughnut shape with outer diameter of 50cm and inner diameter of 10cm and thickness of 2mm. The position resolution is 70μm There are no ineffective area. And the cost is several million yen.

Light naphtha, which exhibits two-stage ignition, was induced from the intake manifold and water or a low-ignitability fuel, which does not exhibit low temperature oxidation, was directly injected early in the compression stroke for ignition suppression in an homogeneous charge compression ignition (HCCI) engine. Their quantitative balance was flexibly controlled to optimize ignition timing according to operating conditions. Ultra-low NOx and smokeless combustion without knocking or misfiring was realized over a wide operating range with water or alcohol injection. The water injection significantly reduced the low-temperature oxidation, which suppressed the increase in charge temperature and the rapid combustion caused by the high-temperature oxidation. Rapid combustion was suppressed by reductions in the maximum in-cylinder gas temperature due to water injection while the combustion efficiency suffered. Therefore, the maximum charge temperature needs to be controlled within an extremely limited range to maintain a satisfactory compromise between mild combustion and high combustion efficiency. Alcohols inhibit low-temperature oxidation more strongly than other oxygenated or unoxygenated hydrocarbons, water, and hydrogen. Chemical kinetic modelling with methanol showed a reduction of OH radical before the onset of low-temperature oxidation, and this may be the main mechanism by which alcohols inhibit low-temperature oxidation.

To furnish semiconductor surfaces at device fabrication, control of micro-structures is expected of the most importance in the near-future. Highly sensitive measurement of desorption from Cl-adsorbed Si(1 1 1) surface indicated that a diffusive process plays an important role on the surface. The desorption barrier was estimated to be 2.2 eV from temperature-dependence of time-course in isothermal desorption, suggesting the desorption site contains distortion. Defects, which may be steps or clusters, are the dominant sites where the associative reaction occurs. In STM images, clusters were observed at step edges, as well as growth of pits and defects. From comparison of the desorption with high temperature STM images, a cluster pins the step movement to form step bunches. Interaction between clusters through the step movements makes clusters aligned. Ordered structures can be obtained when velocity of the surface diffusion matches the rate of the chloride desorption.

Existing PET (Positron Emission Tomography) systems make clear images in demonstration (measuring small PET reagent in pure water), however images in real diagnosis become unclear. The authors suspected that this problem was caused by Compton scattering in a detector. When PET systems observe plural photomultiplier tube outputs, an original emission point is regarded as centroid of the outputs. However, even if plural emission in Compton scattering occur, these systems calculate original point in the same way as single emission. Therefore, the authors considered that rejecting Compton scattering events makes PET systems much better, and made prototype counter. Main components of the prototype counter are plate-like high-growth-rate (HGR) La-GPS scintillators and wavelength shifting fibers (WLSF). HGR crystals grow 10 times as fast as a mono-crystal (a normal mono-crystal grows at 2 – 3 mm an hour). Thus, it includes microbubble and its transparency get worth. Consequently, HGR crystals usually are not used in radiation measuring instruments. However, this time they are used on the purpose. Because of their low transparency, scintillation lights come out right above and right under of emission position. Therefore, Compton scattering events is rejected easily. The prototype detector has an effective area of 300 by 300 square mm. The detector consists of 24 layers. One layer consists of HGR La-GPS scintillator of 1 mm thickness. Top and bottom surface of scintillator were covered by dual sheets of WLSF with a diameter of 0.2 mm. Sheets of WLSF on top and bottom of the scintillator make a right angle with each other, and measure X- and Y-components. Z-component is measured by difference of WLSF outputs between top and bottom. If plural layers output signals, this counter regards the event as Compton scattering event, and reject the event. Even if only a layer output signals, the event is rejected when number output signals from WLSF is more than 1.5 times of single emission. Material cost of this system is, 0.2M$ for HGR La-GPS, 0.03M$ for WLSF, 0.03M$ for 600 units of 6 by 6 mm SiPM's, 0.12M$ for 12000 units of 1 by 1 mm SiPM's, and 0.09M$ for 1800 channel of signal readout circuits. Considering total cost, price of this PET will be set 1M$ or less. This idea was confirmed with numerical simulation and experimentation. In experimentation, position resolution in photoelectric absorption was 0.2 mm, and minimum distance that this detector could recognize plural emission in Compton scattering was 1 mm. In parallel, three kinds of model were made: a prototype detector, all the signals readout method, and resistance delay method. Simulation setting was 2 MBq/L in normal tissue and 10 MBq/L in cancer. As a result of simulation, a prototype detector identified 3 mm cancer, however the others made unclear image and was not able to identified cancer. That is to say, the prototype detector is able to reject Compton scattering events and inexpensive. Therefore, whole-body PET system with this detector must diagnose cancer with a diameter of 3 mm or more and be priced 1M$ or less

The adsorption process of chlorine on Si(111)7×7 has been studied by means of real-time surface differential reflectance (SDR) spectroscopy and second harmonic generation. Time evolution of adsorption on adatom dangling bonds and breaking of adatom back bonds are obtained from SDR spectra and second harmonic intensity. The initial sticking probability on the dangling bonds and the initial breaking probability of the back bonds are determined by fitting the time evolution to the solutions of the rate equations for the adsorption of atoms without migration. Temperature dependence of these probabilities reveals that both the adsorption on adatom dangling bonds and breaking of adatom back bonds proceed without potential barriers, and that a metastable state exists in the breaking process of the back bonds.

Bright green and blue light emitting diodes have been developed based on ZnSSe:Te active layer, with high crystal quality and a close lattice-match to GaAs substrate. The green LEDs exhibit a fairly long lifetime (>2000 h) at room temperature, which is attributable to the crystal-hardening effect by Te-doping. The devices show slow-mode degradation due to the gradual enhancement of microscopic defects in p-ZnMgSSe cladding layer. No detectable changes in dark-spot and dark-line formation due to macroscopic defects are observed during device operation.

Holmes’ tremor is an unusual combination of 2–5 Hz resting, postural, and kinetic tremors affecting the unilateral upper extremity, which is usually caused by stroke, trauma, vascular malformations, or tumors involving the midbrain [1]. Abnormal involuntary movements such as tremor affect the quality of life by interfering with simple motor tasks and daily activities. Pharmacotherapy for Holmes’ tremor does not usually achieve satisfactory results and some patients require thalamic surgery to control this tremor [2]. Zonisamide (ZNS), 3-sulfamoylmethyl1,2-benzisoxazole, was originally developed as a broadspectrum antiepileptic drug. Recent clinical studies have suggested several new indications for ZNS, including Parkinson’s disease, essential tremor, and psychiatric diseases [3]. Here we report a patient in whom delayed Holmes’ tremor after subarachnoid hemorrhage responded dramatically to ZNS. A 68-year-old, right-handed woman with a history of hypertension developed headache and drowsiness. Neurological examination revealed dysarthria, right oculomotor nerve paralysis, and left hemiparesis [2/5 by manual muscle testing (MMT)]. On admission, brain computed tomography and magnetic resonance imaging (MRI) showed subarachnoid hemorrhage together with right midbrain hemorrhage (Fig. 1a–c). An aneurysm of the basilar artery/right superior cerebellar artery was detected by MRI and digital subtraction angiography (Fig. 1d, e), and was treated by coil embolization (Fig. 1f, i, j). During follow-up for 15 months, her right oculomotor nerve palsy improved slightly and her left hemiparesis improved to 4/5 on MMT. She was able to look after herself without assistance. However, a slow, strong, and large-amplitude tremor affected her left upper limb. The tremor was worsened by emotional stress and disappeared during sleep. It was exhausting and rendered her left arm useless. T2-weighted and fluid attenuated inversion recovery MRI of the brain showed a low intensity to hyperintense area in the right midbrain, corresponding to the site of hemorrhage, without any evidence of additional vascular pathology in the basal ganglia (Fig. 1g, h). A diagnosis of Holmes’ tremor was made. Her tremor was assessed by employing item 20 (tremor at rest) and item 21 (action or postural tremor) of the Unified Parkinson’s Disease Rating Scale (UPDRS). Initial treatment with levodopa (150 mg/day) and a dopamine agonist (pramipexole at 1.5 mg/day) improved the subscore from 3 to 1 for the resting component of her tremor, but the postural and kinetic components were unchanged (subscore of 4). She refused to take dopaminergic agents because of nausea. Therefore, ZNS was started at a dose of 100 mg twice daily. After a few days, her resting and postural/kinetic tremors were markedly improved from 3 to 1 and from 4 to 1, respectively, and she was able to perform most daily activities by herself, such as cooking, eating meals, changing clothes, and cleaning. ZNS therapy has been well tolerated, and improvement of her tremor persists after 8 months of follow-up. S. Suda (&) M. Yamazaki K. Katsura T. Fukuchi M. Ueda H. Nagayama Y. Katayama Divisions of Neurology, Nephrology, and Rheumatology, Department of Internal Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan e-mail: suda-sa@nms.ac.jp

We propose a positron detector with 8 layers of scintillation fibers whose length is 1 m and whose diameter is 0.2 mm. The shape of this detector is like as endoscope but one layer of fibers is spirally rolled clockwise, and another layer is counter-clockwise. The pitch of inner and outer spiral fibers are 85 and 75mm, respectively. This detector can be installed into the intestines from the anus, and positrons emitted from PET agents can be directly measured. The azimuth angle and z-coordinate of incident positrons are determined from the 4 types of hit fibers. This inspection can be performed at the same time as the standard PET examination.

Single crystals of strontium barium niobate (SBN) solid solution, (Sr x Ba 1− x ) 1− y (Nb 2 O 5 ) y , 0.75⩾ x ⩾0.40, 0.5050⩾ y ⩾0.4975, were grown by the floating zone method. There are two series of the crystals. x varies and y is fixed at 0.5 in the first series of crystals. x is fixed at 0.61 and y varies in the second series. The typical size of the grown crystal is 5 mm in diameter and 70 mm in length. All crystals, regardless of the compositions, revealed the facet parallel to the c -plane and the clear striations. A part around the crystal can be easily broken due to hoop stress. The spontaneous growth-direction of SBN is 〈0 0 1〉. The congruent melting composition of SBN is revealed by employing a zone-melting method at the final stage of growth experiments. It is (Sr 0.61 Ba 0.39 ) 0.5015 (Nb 2 O 5 ) 0.4985 . The absorption edges of the crystals in both series are around 360 nm and are shifted by 10 nm toward blue in comparison with those of the crystals grown by CZ method.

With the aim of finding an optimum crucible for growth of Pr2−xCexCuO4 crystal, reactions between CuO flux and various crucible materials were studied. Among six different crucible materials, Pt, Al2O3, ZrO2, Y2O3, CeO2 and MgO, Pt crucible was suitable for using Ce free solution. For Ce doped solution, MgO crucible was better than other materials. The reactant between Pt crucible and CuO flux was identified as Pt2Cu. In the case of MgO crucible, Mg2CuOx and (Mg,Cu)Ox were produced as reactants. We found a method to restrain the reaction between the crucible and the solution. Using this method for growth of Ce doped crystal, we grew a crystal of size 30 mm∅×1.5 mm.