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An 88-year-old man with congenital hemophilia A developed end-stage renal disease due to microscopic polyangiitis. He was at risk for catheter-related infection because he was taking immunosuppressive agents for the treatment of polyangiitis. He was also unable to manipulate the peritoneal dialysis device. Therefore, hemodialysis using an arteriovenous fistula was induced for renal replacement therapy. Recombinant coagulation factor VIII (1000 IU) was administered via the venous chamber of the hemodialysis circuit 10 min before the end of each hemodialysis session, and nafamostat mesylate (25 mg/h) was employed as an anticoagulant during hemodialysis. His clotting factor VIII activity level increased to > 50% and activated partial thromboplastin time decreased to 50 s at the end of each hemodialysis session. This method allowed him to achieve hemostasis at the puncture site of the arteriovenous fistula and undergo stable hemodialysis with no complications, including bleeding. This case suggests that hemodialysis using an arteriovenous fistula with coagulation factor replacement and nafamostat mesylate in each hemodialysis session is a therapeutic option for end-stage renal disease in patients of advanced age with hemophilia at high risk of bleeding.

In previous research, we developed a three-dimensional (3D) boundary magnetic charge method (BMCM) for high-accuracy field calculations in a static magnetic field, even when there exist great differences between the magnitudes of permeability between neighboring magnetic materials. This method, however, cannot be applied to a system that contains saturated magnetic materials. In the present study, therefore, we have developed a novel method that addresses this issue. According to this new method, we divide the region containing the magnetic material into small-volume elements and divide the boundaries between neighboring small-volume elements into small-surface elements, assigning each element an appropriate initial value of permeability. The magnetic field inside and outside of the magnetic material is calculated using this permeability. The value of the permeability of each element is iteratively updated using μ–H data. The updated value of the permeability after the i-th iteration, μi, is compared with that of the previous value, μi−1. If the difference between the two values is within a preset range, the iteration process is judged to have converged and the value of μi is regarded as the final converged value of the permeability. The magnetic field at an arbitrary point in space and/or inside the body of the magnetic material is calculated from the converged permeability of each element. As a result, we have succeeded in developing a novel BMCM for the calculation of a static magnetic field with high accuracy in a system containing saturated magnetic materials.

Field-emission spectroscopy (FES) is a technique that acquires an energy spectrum of the electrons emitted from a field emitter. A cylindrical deflector analyzer (CDA) is often used for FES. Assuming that the electric field in the CDA is an ideal cylindrical field, it is known that the optimum deflection angle is 127°. In fact, there is a deviation from an ideal cylindrical field in the CDA. In particular, a fringing field occurring at the vicinity of entrance and exit of slits is not negligible. Therefore, herein, we performed three-dimensional (3D) electric field calculations and ray tracing using a 3D boundary charge method (BCM) that we developed previously. Using this approach, the CDA can be optimized to improve the energy resolution of FES.

We developed an electron optical instrument for evaluating multi-emitters. This device enables us to evaluate both the percentage of active tips and the stability of the emission current from each active tip. Herein, we employed the instrument to observe a volcano-structured Spindt-type field emitter array (FEA) in the photoelectron emission microscopy (PEEM) and field electron emission microscopy (FEEM) modes. Furthermore, we measured the emission current from each active tip in the FEA. Consequently, we found that the number of active tips in the FEA can be considerably increased by aging at a relatively high voltage.

Photobiomodulation or low level laser therapy (LLLT) has been utilized in various areas of medical practice including pain relief, wound healing, and inflammation treatment. Some recent animal studies have reported that near-infrared laser irradiation to the lumbosacral nerves transcutateously relieves neuropathic pain by controlling activity of lumbosacral nerves. However, transcutaneous laser penetration to the nerves has not yet been fully elucidated. Our aim is to determine the light penetration to lumbosacral nerves when near-infrared laser was irradiated transcutateously to lumbosacral nerves. We implanted photodiodes near the lumbosacral nerves of rats and connected the photodiodes to an oscilloscope through an amplifier. Near-infrared lasers (wavelengths: 808 nm and 830 nm) were irradiated through the skin at 2, 5 and 10 W pulses (Duty 10%, 5 Hz) and outputs of photodiodes were collected. After irradiation, the depth of the photodiodes and the nerves from the skin surface were determined by micro-CT device. The result showed that the fluence rate at the lumbosacral nerves was 179±19.2 mW/cm 2 and 232±20.7 mW/cm 2 when the 808-nm and 830-nm laser was irradiated at 10 W respectively. These findings would be beneficial for following study of photobiomodulation.

High-quality color output from digital photocopiers and laser printers is in strong demand, motivating attempts to achieve fine dot reproducibility and stability. The resolution of a digital photocopier depends on the charge density distribution on the organic photoconductor surface; however, directly measuring the charge density distribution is impossible. In this study, we propose a new electron optical instrument that can rapidly measure the electrostatic latent image on an organic photoconductor surface, which is a dielectric surface, as well as a novel method to quantitatively estimate the charge density distribution on a dielectric surface by combining experimental data obtained from the apparatus via a computer simulation. In the computer simulation, an improved three-dimensional boundary charge density method (BCM) is used for electric field analysis in the vicinity of the dielectric material with a charge density distribution. This method enables us to estimate the profile and quantity of the charge density distribution on a dielectric surface with a resolution of the order of microns. Furthermore, the surface potential on the dielectric surface can be immediately calculated using the obtained charge density. This method enables the relation between the charge pattern on the organic photoconductor surface and toner particle behavior to be studied; an understanding regarding the same may lead to the development of a new generation of higher resolution photocopiers.

Neuropathic pain, a highly debilitating condition that commonly occurs after damage to the nervous system, is often resistant to commonly used analgesic agents such as non-steroidal anti-inflammatory drugs and even opioids.Several studies using rodent models reported that cannabinoid CB2 receptor (CB2R) agonists are effective for treating chronic pain. However, the analgesic mechanism of CB2R agonists in neuropathic pain states is not fully understood. In this study, we investigated the role of CB2Rs in the development and maintenance phases of neuropathic pain, and the mechanism of the CB2R-mediated analgesic effect on neuropathic pain. In a rat model of neuropathic pain, systemic administration of JWH133, a CB2R agonist, markedly improved tactile allodynia, and this effect was prevented by intrathecal pretreatment with AM630, a CB2R antagonist. The antiallodynic effect of intrathecally administered JWH133 was inhibited by intrathecal pretreatment with pertussis toxin or forskolin. In the spinal cord, CB2R expression was significantly increased on post-operative day 3, and persisted for 2 weeks. Furthermore, repeated intrathecal administration of JWH133 notably attenuated the development of tactile allodynia after peripheral nerve injury. In a culture of microglia activated by overexpressing interferon regulatory factor 8, a transcription factor crucial for neuropathic pain, JWH133 treatment suppressed the increased expression of interleukin-1β. Our findings suggest that activation of CB2Rs upregulated in the spinal cord after nerve injury alleviates existing tactile allodynia through the Gi/oadenylate cyclase signaling pathway and suppresses the development of allodynia. This process may reduce the inflammatory response of microglia. Therefore, spinal CB2Rs may be a therapeutic target for the treatment of neuropathic pain.

The electric field strength on the emitter surface is the most important parameter because it strongly influences the gun performance. We have found that the electric field strength on the emitter surface can be estimated experimentally from the Schottky plot whose slope depends not on the work function but only on the reciprocal of the emitter temperature.

We fabricated nanometer-size pyramids with three {211} -facet sides (nanopyramids) on blunt W tip and observed their atomic structures by field ion microscopy (FIM). The blunt W tip was preliminary subjected to remolding treatment in order to sharpen its end. Owing to the atomic resolution of FIM, we found that the {211} and {110} planes faceted markedly as a result of the remolding treatment and clearly detected the neighboring {211} and {110} planes were separated by a monoatomic chain along the direction. In addition, the (111) plane was raised and narrowed owing to the faceting of the three surrounding {211} planes. Dimension of the narrowed (111) plane was about 3 nm. By using the surface of the remolded-tip end as a substrate, we grew the nanopyramid by depositing Pd atoms and elevating the sample temperature to 1000 K. The FIM observation indicated typical signs for the nanopyramid growth such as markedly-faceted {211} planes, monoatomic linear chains for the pyramid ridge, and extremely narrow top of the pyramid. In this study, the top was the third layer of the ideal nanopyramid counting from the top. Along with previous field emission data [E. Rokuta, T. Nakagawa, H. Murata, S. Fujita, H. Shimoyama, and C. Oshima, Jpn. J. Appl. Phys. 50, 115001 (2011).], the remolding treatment was proven to be useful for the nanopyramid growth on the blunt end of the W tip. [DOI: 10.1380/ejssnt.2012.12]

The generalized trajectory theory (the G-optk program) has been extended in order to make the method applicable to electron guns with curved and/or asymmetric cathodes. The object-image analysis mode has also been added. Enhanced capability of the upgraded G-optk program was demonstrated by applying the program to three electron optical systems: (a) the point cathode gun, (b) the hairpin-type cathode gun, and (c) the LEEM objective lens. The Canonical Mapping Transformation (CMT) diagrams were calculated both by direct ray tracing and by the upgraded G-optk program. In each case, it was found that the upgraded program reproduces well the results obtained by ray tracing. The generalized trajectory method has several advantages over direct ray tracing, such as substantially lighter calculation load and easy interpretation of the calculation results in terms of the optical parameters.

A simple and quick method to measure the electric field distribution near a specimen using a conventional transmission electron microscope has been developed. The electric field distribution around a field emitter needle was measured to evaluate the performance of the method. It was found that this method allows us to measure the 2D distribution of electric field quantitatively with error of

We have developed an electron optical instrument for evaluation of multi emitters. The instrument is a versatile emission microscope and is capable of operating as a secondary electron emission microscope (SEEM), a photo electron emission microscope (PEEM) and a field electron emission microscope (FEEM) imaging modes. The most important feature of the instrument is the capability of simultaneous observation of SEEM and FEEM images as well as PEEM and FEEM images in real time and in-situ mode. The operating condition of the multi emitters can be observed in DC mode as well as pulse mode. Thus, the instrument enables us to obtain quantitative knowledge as to the percentage of actually working emitters out of the whole emitters and to evaluate the stability of the emission current from each individual working emitter. [DOI: 10.1380/ejssnt.2010.266]

Neuropathic pain, a highly debilitating pain condition that commonly occurs after nerve damage, is a reflection of the aberrant excitability of dorsal horn neurons. This pathologically altered neurotransmission requires a communication with spinal microglia activated by nerve injury. However, how normal resting microglia become activated remains unknown. Here we show that in naive animals spinal microglia express a receptor for the cytokine IFN-γ (IFN-γR) in a cell-type-specific manner and that stimulating this receptor converts microglia into activated cells and produces a long-lasting pain hypersensitivity evoked by innocuous stimuli (tactile allodynia, a hallmark symptom of neuropathic pain). Conversely, ablating IFN-γR severely impairs nerve injury-evoked microglia activation and tactile allodynia without affecting microglia in the contralateral dorsal horn or basal pain sensitivity. We also find that IFN-γ-stimulated spinal microglia show up-regulation of Lyn tyrosine kinase and purinergic P2X 4 receptor, crucial events for neuropathic pain, and genetic approaches provide evidence linking these events to IFN-γR-dependent microglial and behavioral alterations. These results suggest that IFN-γR is a key element in the molecular machinery through which resting spinal microglia transform into an activated state that drives neuropathic pain.

It has been attempted to characterize the cathode rays inside electron guns by utilizing the optical concepts familiar in the paraxial lens theory. We have proposed the Canonical Mapping Transformation (CMT) theory to obtain the gun optical parameters. The method is based on the Lagrange differential invariant theorem known in analytical mechanics. It has been found that major electron source properties, such as the crossover position, crossover size, and the angular current intensity, are all deducible from the four CMT optical parameters ( zco , f , Csg , and Ccg ), which in turn can be estimated by calculating the normal electron rays, whose emanation vectors on the cathode surface are in the surface normal direction. Since the normal electron rays can in many cases be regarded as paraxial, a scheme has been proposed to calculate the relevant optical parameters by a modification of the conventional paraxial trajectory calculation. It is shown that the normal electron ray of the CMT theory corresponds to (1, 0) principal trajectory in the paraxial method, g(z) . The conventional perturbation characteristic function integral method can be employed for the evaluation of the CMT aberration coefficients. Two realistic electron gun models (a single-crystal LaB6 cathode gun and a Schottky emitter source) were analyzed by use of the CMT optical parameters. Both the ray tracing of the normal electrons and the modified paraxial calculation method were employed for the analyses. It has been found that the guns with quite different nature in the source properties can well be described by the CMT optical parameters proposed. The paraxial calculations have been shown to produce accurate enough results and the authors hope their use would help electron optical column designers both in reducing the work load and in having clear physical images of their gun characteristics. © 2008 Elsevier B.V. All rights

We proposed a technique which arranges particles in a regular two-dimensional array on an azopolymer surface, followed by immobilizing them in an arbitrary pattern on the surface, and studied its prospect. Azopolymer has the two properties of being able “to form a surface relief structure” and “to immobilize particles in the surface” by light irradiation. First, the former characteristic was used to form a periodic two-dimensional relief pattern template on an azopolymer surface by two-beam interference exposure, and the particles were arranged on the surface. Then the latter characteristic was used to selectively immobilize particles by light irradiation, and unimmobilized particles were removed by washing. As a result, we demonstrated that particles could be arranged in a regular two-dimensional array in a square structure and a hexagonal structure, and a two-dimensional photonic crystal waveguide structure could be easily fabricated by the micropatterning of particles. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(3): 1–8, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20307

Scanning electron microscope (SEM) observation of an insulator material often suffers an abnormal contrast image from a charging phenomenon, which is caused by accumulation of a part of primary electrons inside the material. In order to avoid the charging phenomenon, it is important to observe the insulator material under the primary electron energy condition that the total electron emission yield σ is equal to unity. In order to find out the above primary electron energy condition, we have measured the electron emission yield σ as a function of the primary electron energy Ep for several insulator materials. In this case the specimen (= the insulator material) has been heated up to 700 °C where the charging phenomenon disappears. The value of σ has been determined by measuring both the primary electron current (Ip) and the conduction electron current (Ia=Ip-σIp) flowing to the ground through the specimen stage. We also found that the primary electron energy corresponding to σ=1 can easily be determined by the condition that the conduction electron current Ia takes a minimum value. For example, the primary electron energy that gives the condition of σ=1 for Si3N4 has been found to be Ep=3.1 keV. We have also measured the secondary electron emission yield δ of the insulator material using the contrast method, which is based on the signal intensity ratio of the SEM image of the boundary between Au and the insulator material.

In this paper, we propose an improved three-dimensional (3-D) boundary charge method for a composite dielectric system where there is a great difference in magnitude of the permittivity between neighboring dielectric materials. The method is based on the idea that the whole region of the composite dielectric system is divided into two regions; one being the region H containing the dielectric material of high permittivity eH and the other being the region L containing the dielectric material of low permittivity eL. The boundary of division is selected so as to coincide with the interface between eH and eL. We then arrange surface charge densities on both sides of the interface between eH and eL as well as on every conductor-to-dielectric interface in respective regions of H and L. The key point of our improved method is that when we calculate the electric field in the region H, for example, we use only the surface charge densities in the same region and do not use those in the region L. When we calculate the electric field in the region L, a similar rule is applied. In order to determine the surface charge density on every interface we utilize boundary conditions for potential and electric field at every interface. This procedure eliminates the loss of numerical accuracy arising from cancellation in addition, and we have succeeded in improving numerical accuracy even when there is a great difference in magnitude of the permittivity between neighboring dielectric materials.

In this paper we propose a three-dimensional (3-D) boundary magnetic charge method (BMCM) in order to treat a static magnetic field system where there is a great difference in magnitude of permeability between neighboring magnetic materials. The method is based on the improved 3-D boundary or surface charge method (BCM or SCM) developed for high-accuracy calculation of the potential and electric field distributions in a composite dielectric system. The calculation of magnetic field by the 3-D BMCM is completely parallel with the calculation of the electric field by the 3-D BCM. The numerical accuracy of the 3-D BMCM is examined by using a computing model which gives an analytical solution of the magnetic field. We have found that the numerical accuracy of the present method is independent of the magnitude of the permeability and improves in proportion to the square of the number of the small surface elements.

Deformation of an organic photosensitive azopolymer by near-field light generated by an optical fiber probe with a very small aperture diameter of about 50 nm is studied. The azopolymer is deformed in response to the polarization state of the light incident on the probe. If the probe aperture diameter is made smaller, the mark shape can be made smaller but the probe must be moved closer to the material. However, the mark width is about 6 times the probe aperture diameter. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(3): 55–61, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10129

This paper describes a control and monitoring system for the field emission (FE) gun in the high-voltage electron microscope (HVEM), where the whole FE gun system is located inside a pressure vessel and is floated on a high voltage of 1 MV. The operating condition of the FE gun system is controlled and monitored mainly by a bi-directional communication system between ground and high potential through optical fibres. A mechanical driving system by combination of insulator rods and stepping motors is partially used as a control system for FE gun operation. The monitoring system developed here also functions as a safety circuit that detects abnormal situations, such as an abnormal deterioration of vacuum, and protects the FE tip against fatal damage. The fundamental performance of the microscope has been tested for transmission electron microscope (TEM) and scanning TEM operation modes.

High quality multiwalled carbon nanotubes (MWNTs) prepared by hydrogen DC arc discharge were purified by infrared irradiation in air at about 500°C. The morphology and nanostructure of the purified MWNTs were investigated by using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and micro-Raman spectroscopy. Each MWNT was highly graphitized and most of the MWNTs had approximate 1.0 nm inner diameter. The radial breathing modes corresponding to the innermost nanotubes were observed in the micro-Raman spectra of the purified MWNTs. The dependence on the incident laser power of Raman-allowed mode, E2g, and new Raman peak at about 1840 cm−1 was also studied.

The effect of Ni and Y concentrations in bimetallic Ni–Y catalyst on single-wall carbon nanotube (SWNT) generation is studied. When we added small amount of Y with the order of 0.1 atomic % (at%) against C, the generation rate of soot in arc discharge was enhanced by a factor of 2–3 as compared with that of only C. Addition of Ni well enhanced the generation of SWNTs. The tube diameter distribution was controlled by changing Y concentration (0–9.0 at%), but was not sensitive to Ni concentration (0.2–3.0 at%). The mean tube diameter was increased with increasing Y concentration.

We have developed a reliable and efficient battery-charging system for the field emission (FE) gun system of high voltage electron microscopes, where the operating condition of the whole FE gun system can be controlled and monitored through a bi-directional optical fiber system, and the control and monitoring circuits located on the high potential of 1 MV are driven by rechargeable Ni-Cd batteries. The power transmission from ground to the high potential is performed through filter condenser circuit. Under the condition that the filter condenser current is limited to 0.2 A(rms) (root-mean-square value), it is possible to transmit the maximum power as high as 65 W, which is enough for the daily operation of the FE gun system. The charging circuit has a function of protecting the batteries from over-charging.

Graphite evaporation by DC arc discharge in rarefied hydrogen gas forms three types of carbon allotropes on the cathode surface as carbonaceous deposit. Typical one is multiwalled carbon nanotubes (MWNTs) found in the central region of the cathode deposit. Other carbon allotropes are carbonaceous hard outer shell and petal-like graphene sheets. As-grown MWNTs could be easily purified by removing few co-existing carbon nanoparticles with the use of thermal etching in air. The X-ray diffraction patterns of purified MWNTs were similar to those of graphene sheetsand those of the outer shell and the raw graphite rod bore a resemblance to each other. In Raman spectra of purified MWNTs, downshift more than 10cm-1 was observed for the first order Raman-allowed phonon mode. Particular new peaks of Raman spectra for purified MWNTs were also observed.

Evaporation of graphite electrodes in H 2 gas by DC arc discharge was found to form not only multiwalled carbon nanotubes (MWNTs) but also graphene sheets in the cathode deposit. By irradiating the deposit surface using an infrared radiation heating system in air, the MWNTs could be easily purified. The morphology and structure of as-grown MWNTs, graphene sheets and purified MWNTs were investigated using scanning electron microscopy, high-resolution transmission electron microscopy and X-ray diffraction. X-ray diffraction patterns of MWNTs and graphene sheets were similar to each other.

Numerical calculations have been conducted on the electron optical characteristics of the accelerating tube (AT) for the high voltage electron microscope (HVEM) equipped with the field emission gun (FEG). The emitted electrons are firstly accelerated to V0 by the FEG and finally to Va by the AT which consists of 34 stages of accelerating electrodes with an inner diameter of 33 mm and has an overall length of 1423 mm. The AT is treated as a thick electrostatic accelerating lens. Several electron optical problems arising from a combination of the AT with the FEG are studied. In order to reduce an unfavorable aberration effect of the AT-lens, the beam crossover must be brought to a position near the entrance plane of the AT. This can be done by a transfer lens which is placed between the FEG and the AT. The introduction of a partial retarding field in the AT is also very effective for a flexible operation of the FEG system without serious aberration effects of the AT-lens.

Thermal field emission (TFE) characteristics of single-crystal LaB 6 columnar tip were investigated. After adequate cleaning treatment, TFE was continuously stable at 1600 K and 1700 K in 10−8 Pa. Emission patterns indicated that TFE could be regarded as uniform if we took it into account that the size of the emission region practically used for the e-beam lithography was about 0.5 mm on the fluorescence screen.

The purpose of the present study is to examine the feasibility of a high brightness and high beam current electron gun with an elongated lifetime from perspective of computer simulation. We propose a novel electron gun system with LaB 6 cathode which is operated at Schottky emission mode under slightly lower temperature condition than that typically used for thermionic emission mode. The design of the electron gun system and the operational condition are optimized so that both the brightness and the beam current are high enough for high-throughput electron beam lithography.

A photoimprint-based immobilization process is presented for cylindrical viruses on the surface of an azobenzene-bearing acrylate polymer by using atomic force microscopy (AFM). Tobacco mosaic virus (TMV), 18 nm in diameter and ca. 300 nm in length, was employed as a model virus. First, a droplet of an aqueous solution containing TMV was placed on the acrylate polymer surface. After drying the droplet, the polymer surface was irradiated with light at a wavelength of 470 nm from blue-light-emitting diodes. Finally, the surface was washed by aqueous solution with detergents. The polymer surface was observed at each step by AFM. TMV was shown to embed itself gradually on the polymer surface during photoirradiation in a time scale of tens of minutes because of the formation of the surface groove complementary to the shape of TMV. Analysis of immobilization efficiency of TMV on the polymer surface by the immunological enzyme luminescence indicated that efficiency increased proportional to the photoirradiation time. In these experimental conditions, the absorption band of the azobenzene moiety remained constant before and after the photoirradiation. These results show that TMV is physically held on the complementary groove formed on the polymer surface by the photoirradiation.

The paraxial trajectory method has been generalized for the application to the cathode rays inside electron guns. The generalized method can handle rays that initially make a large angle with the optical axis with a satisfactory accuracy. The key to success of the generalization is the adoption of the trigonometric function sine for the trajectory slope specification, instead of the conventional use of the tangent. Formulas have been derived to relate the ray conditions (position and slope of the ray at reference planes) on the cathode to those at the crossover plane using third-order polynomial functions. Some of the polynomial coefficients can be used as the optical parameters in the characterization of electron sources; the electron gun focal length gives a quantitative estimate of both the crossover size and the angular current intensity. An electron gun simulation program G-optk has been developed based on the mathematical formulations presented in the article. The program calculates the principal paraxial trajectories and the relevant optical parameters from axial potentials and fields. It gives the electron-optical-column designers a clear physical picture of the electron gun in a much more faster way than the conventional ray-tracing methods.

Recently, much attention has been refocused on a single-atom field emitter (SAFE), which is a noble-metal-covered nanopyramid terminated with one atom on a W nano-cathode tip. The SAFE has a self-repairing function and a demountable characteristic, and provides an electron point source of single-atom dimension. Experimental results [1] show that the electron beam emitted from the SAFE is narrowly confined to approximately ±3 degrees. Although the narrow confinement of the emitted electron beam has been explained by some possible mechanisms, such as the quantum mechanical effect or electric field distribution around the SAFE, it remains unclear. The purpose of our study is to clarify why the electron beam is so narrowly confined.

Recently, atomic-scale, thermodynamically stable pyramids with a single atom end have been fabricated from W tips, and developed as a point source of field-emitted electrons. Not only did they exhibit superior characteristics like high brightness, narrow spread, and considerable stability of the e-beam [1], but they represented both self-repairing and demountable functions that were requisites for practical application [2]. As far as how to produce the nano-pyramids is concerned, various necessary conditions are involved in the recipe. One of the critical requisites is a use of so-called “ultra-sharp” W tips. To our best knowledge, even if the identical treatments are given to a “blunt” W tip, the nano-pyramid with a single-atom end does not grow, seemingly due to a heavy load of mass transport. Compared to the ultra-shape W tips, however, the blunt ones are considered more favorable because of high resistance against both thermal and mechanical damages. In this study, we have sharpened the W-tip end by means of remolding [3], which is a sort of thermal-field treatment, prior to the nano-pyramid production. Thus, we have tried and formed the nano-pyramid using originally blunt W tip as a starting substrate.

The shape change of the ⟨100⟩-oriented tungsten single-crystal field emitter tip under thermal-field (TF) treatment was systematically studied with increasing remolding field (i.e., reversely polarized field opposite to field-emission polarity) at a constant temperature. The initially hemispherical emitter tip builds up to polyhedral shapes with increasing remolding voltage. These shapes are formed by certain low-index crystal planes. On further increase of the voltage, an overremolding state is reached in which the emitter takes a rugged surface structure. A thermodynamic model is proposed to explain the buildup mechanism utilizing the reduction of the surface tension under the influence of a strong electric field. The theory assumes the emitter-extractor system to comprise an electric capacitor and includes the electrostatic-field energy stored around the emitter into the system under consideration. It is shown that the electrostatic-field energy term in the Gibbs free energy could be interpreted as an effective reduction of the surface tension. The initially moderate anisotropy of the intrinsic surface tension is increasingly enhanced by the electrostatic-field energy through the reduction mechanism. The facets on the emitter surface consequently develop in accordance with the Wulff construction of the equilibrium crystal shape (ECS). By application of an electric field, the surface free-energy anisotropy can be made large enough to induce complete faceting of the crystal even at an elevated temperature where the crystal shape can immediately follow the ECS.

A new numerical simulation method is presented for the electron optical property analysis of probe forming systems with point cathode guns such as cold field emitters and the Schottky emitters. It has long been recognized that the gun aberrations are important parameters to be considered since the intrinsically high brightness of the point cathode gun is reduced due to its spherical aberration. The simulation method can evaluate the 'threshold beam current I(th)' above which the apparent brightness starts to decrease from the intrinsic value. It is found that the threshold depends on the 'electron gun focal length' as well as on the spherical aberration of the gun. Formulas are presented to estimate the brightness reduction as a function of the beam current. The gun brightness reduction must be included when the probe property (the relation between the beam current l(b) and the probe size on the sample, d) of the entire electron optical column is evaluated. Formulas that explicitly consider the gun aberrations into account are presented. It is shown that the probe property curve consists of three segments in the order of increasing beam current: (i) the constant probe size region, (ii) the brightness limited region where the probe size increases as d approximately I(b)(3/8), and (iii) the angular current intensity limited region in which the beam size increases rapidly as d approximately I(b)(3/2). Some strategies are suggested to increase the threshold beam current and to extend the effective beam current range of the point cathode gun into micro ampere regime.

The paraxial lens theory cannot directly be applied to the cathode trajectories inside the gun. This inconvenience makes the interpretation of cathode trajectories difficult since one cannot use the physical concepts familiar in the paraxial lens theory, such as focal length and magnification factor. We have proposed the canonical mapping transformation (CMT) to describe the electron trajectories inside the gun by relating the ray conditions on the cathode surface to those in the crossover plane. The method takes as variables the distance along the surface and the sine of the ray angle with respect to the surface normal to define ray conditions. It has been shown that the CMT can be characterized by a small number of optical parameters. One of the parameters is the 'electron gun focal length', an extension of the image side focal length in the paraxial lens theory. The crossover size of a triode gun can be calculated from the electron gun focal length and the initial transverse energy spread. The calculation predicts the dependence of the crossover size on the grid voltage due to the change in the electron gun focal length. The prediction is compared with the measurement and shows good agreement with it. Since the CMT optical parameters can be calculated from the representative trajectories only and as they predict practically all the necessary source properties of guns, the CMT can be used as a practical tool in the designing of various types of electron guns.

An electron optical instrument for evaluation of emission characteristics of multi emitters is developed to perform the following functions: (1) observation and recording of dynamical behaviors of emission patterns from the whole multi emitter unit as well as each individual working emitter; (2) image observation of geometrical shapes of individual emitters and gates; (3) measurement of emission current stability from the whole multi emitter unit as well as each individual working emitter. A field emitter array type of multi emitter is used as a specimen. The instrument is found to have the capability of real time and simultaneous observation of LEEM and FEEM images as well as PEEM and FEEM images.

Summary form only given. In this paper, we have developed electron optical instrument for evaluation of multimeters such as field emitter arrays. The instrument is a kind of an emission microscope, in which a magnified image of a specimen itself. The instrument is equipped with a beam illumination system that irradiated the specimen with electron beam or UV light for obtaining secondary (or reflected) electrons or photo electrons from the specimen, and is capable of operating as an FEEM, a PEEM and an LEEM.

INTRODUCTION: To predict the postoperative total renal function after renal surgery, we measured preserved renal cortex volume and examined the estimation of postoperative eGFR of from preoperative multidetector CT. MATERIALS AND METHODS: From 2011 to 2013, 39 patients with preoperative contrast enhanced multi detector CT were underwent renal removal surgery at Teikyo University Hospital. Preoperative and postoperative renal function were assessed by estimating glomerular filtration rate (eGFR). The renal cortex volume (RCV) was calculated automatically by imaging volumetry computer software. Addition of normal side RCV and disease side RCV that was subtracted by tumor region determined as total RCV. The postoperative RCV was defined as preserved renal cortex volume (RCV preservation), which is normal side RCV. The factors that affected the postoperative renal function were examined by univariate and multivariate analysis. For developing the models to estimate postoperative eGFR, we used stepwise (backward elimination) method for identifying the predictors. To assess of the relative quality of these statistical models, both Akaike information criterion (AIC) and Root mean square error of the cross validation (RMSE CV) were calculated. Then tour model was examined as the external validation with 10 patients in Jyuntendo University Hospital. RESULTS: The postoperative eGFR value was associated with age (P CONCLUSIONS: Preoperative MDCT based RCV measurements are associated with postoperative renal function in patients undergoing renal surgery. Computer aided image analysis system makes this procedure simple and reproducible method. Combining CT renal volumetry and patient data might be the important prediction tool for postoperative renal function and risk assessment tool for the CKD after renal surgery. Citation Format: Shuji Isotani, Hiroshi Shimoyama, Yasuhiro Noma, Keisuke Saito, Satoru Muto, Hisamitsu Ide, Raizo Yamaguchi, Shigeo Horie. The prediction of postoperative renal function from renal cortex volumetry with preoperative multidetector computed tomography. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 114. doi:10.1158/1538-7445.AM2014-114

In this paper we propose an improved three-dimensional (3D) boundary charge method (BCM) for a composite dielectric system in which insulators, i.e., dielectric materials exist together with conducting electrodes. The method is based on the idea that the composite dielectric system can equivalently be replaced with a conductor system in vacuum by introducing an apparent surface charge density (=true surface charge density + polarization surface charge density), on every conductor-to-dielectric interface and every dielectric-to-dielectric interface. In calculating the apparent surface charge density, whole interfaces are divided into n small surface elements, and the apparent surface (or boundary) charge density on each small surface element is obtained by solving a set of n-dimensional simultaneous linear equations, where the coefficient matrix elements is expressed as a double integral and the diagonal matrix element becomes a singular or nearly singular integral. A high-accuracy and high-speed calculation of the double integral is the key point of the method, and we have succeeded in great improvement of both numerical accuracy and computation time.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Vertically-aligned carbon nanotubes (VA-CNT) are extremely attractive for use as field emission sources. The fieldemission characteristics of VA-CNTs are determined by the electric field strength on the CNT apexes, and thereforedepend strongly on the geometrical parameters such as a radius of curvature of the CNT apex, an average density ofCNTs and non-uniformity of CNT lengths. This paper describes a computer simulation of electric field analysis for VA-CNTs by means of an improved 3-D boundary charge method, where the VA-CNTs are modeled by 9 × 9 CNTsstanding vertically on the cathode substrate. We have calculated the electric field strength on the CNT apex for variousgeometrical parameters of VA-CNTs. It has been found that the electric field on the CNT apex is inversely proportionalto the radius of curvature of the CNT apex, and significantly decreases when the CNT density exceeds 10 9 /cm 2 .Keywords: carbon nanotube, electric field simulation, field emission, boundary charge method, surface charge method