Polarization and intensity of Compton scattering

X-ray spectra scattered at 90° by acrylic resin plates of various thicknesses are measured. The intensity and polarization of Compton-scattered X-rays are estimated from the spectra. As the thickness of the slab increases, the intensity increases but the polarization decreases. The optimal thickness for a polarized X-ray fluorescence spectrometer is determined, which provides both high intensity and high polarization

Atiyah-Patodi-Singer index on a lattice

We propose a non-perturbative formulation of the Atiyah-Patodi-Singer(APS) index in lattice gauge theory, in which the index is given by the $\eta$ invariant of the domain-wall Dirac operator. Our definition of the index is always an integer with a finite lattice spacing. To verify this proposal, using the eigenmode set of the free domain-wall fermion, we perturbatively show in the continuum limit that the curvature term in the APS theorem appears as the contribution from the massive bulk extended modes, while the boundary $\eta$ invariant comes entirely from the massless edge-localized modes.Comment: 14 pages, appendices added, details of key equations added, typos corrected, to appear in PTE

A case of gastric granular cell tumor

We herein describe an extremely rare case of gastric granular cell tumor (GCT). The gastric submucosal tumor showed a central tiny depression on the surface with a molar tooth-like appearance on esophagogastroduodenoscopy. Our case highlights that gastric GCT should be considered as differential diagnosis of gastric submucosal tumors

Median alveolar cleft and palatal mass without a median upper cleft lip

Median cleft is rare among facial clefts, including bilateral and unilateral clefts. Median upper cleft lip and median alveolar cleft correspond to Type 14 and Type 0, respectively, in Tessier's classification system. Some authors have reported surgical procedures for median cleft. In the case of median alveolar cleft, bone grafting to the cleft side and orthodontics are generally applied, similarly to bilateral or unilateral cleft. Median alveolar cleft is usually accompanied by median upper cleft lip, the degree of which differs in each case. The symptoms include, but are not limited to, median lip defect, wide philtrum, and vermilion notch. However, an isolated alveolar cleft is extremely rare. We encountered a patient with an isolated alveolar cleft who did not have a light median upper cleft lip, such as a wide philtrum or vermilion notch. We herein report this case and describe its treatment

Large-Scale Sequentially-Fed Array Antenna Radiating Flat-Top Beam for Microwave Power Transmission to Drones

Power beaming is one of the core technologies for microwave power transmission (MPT) systems. Effective plane-to-plane power beaming requires not only high point-to-point efficiency but also appropriately-shaped beam to extract the best performance of receivers (rectennas). Flat-top beam plays an important role in plane-to-plane power beaming for drones where the output dc power from rectennas should be maximized to drive motors. It is challenging to develop a large-scale flat-top-beam array with appropriate distribution circuits. Sequential array is also required to suppress axial ratio on the receiving plane. In this paper, we proposed a simplified but effective way to create a large-scale sequential array for flat-top beam at C-band. The series feed and block-oriented sequential array were adopted to keep the circuit design and fabrication simple while obtaining a sufficient point-to-point efficiency and good axial ratio on the receiving plane. A 196-element phased array with microstrip antennas was developed by subdividing the whole array into four 49-element blocks for simplicity of the circuit design and implementation of block-oriented sequential array. The efficiency between the transmitting ports and the receiving ports was 50.6 % in simulations and 32.0 % in measurements. In the measured flat-top beam, the transmitted power was uniformly concentrated within the receiving plane and the axial ratio of the beam was successfully suppressed to less than 3 dB on most of the receiving area. A flight test of a microwave-powered drone was conducted where a micro-drone successfully flew for seven minutes only with wireless power

A noise-driven attractor switching device

Problems with artificial neural networks originate from their deterministic nature and inevitable prior learnings, resulting in inadequate adaptability against unpredictable, abrupt environmental change. Here we show that a stochastically excitable threshold unit can be utilized by these systems to partially overcome the environmental change. Using an excitable threshold system, attractors were created that represent quasi-equilibrium states into which a system settles until disrupted by environmental change. Furthermore, noise-driven attractor stabilization and switching were embodied by inhibitory connections. Noise works as a power source to stabilize and switch attractors, and endows the system with hysteresis behavior that resembles that of stereopsis and binocular rivalry in the human visual cortex. A canonical model of the ring network with inhibitory connections composed of class 1 neurons also shows properties that are similar to the simple threshold system.Comment: 9 pages, 2 tables, and 6 figures. will appear in Phy.Rev.E, vol.79, issue

Cooperative Dynamics of an Artificial Stochastic Resonant System

We have investigated cooperative dynamics of an artificial stochastic resonant system, which is a recurrent ring connection of neuron-like signal transducers (NST) based on stochastic resonance (SR), using electronic circuit experiments. The ring showed quasi-periodic, tunable oscillation driven by only noise. An oscillation coherently amplified by noise demonstrated that SR may lead to unusual oscillation features. Furthermore, we found that the ring showed synchronized oscillation in a chain network composed of multiple rings. Our results suggest that basic functions (oscillation and synchronization) that may be used in the central pattern generator of biological system are induced by collective integration of the NST element.Comment: 13 pages, 4 figure

Preparation of partial-thickness burn wounds in rodents using a new experimental burning device

Objective: The manual application of hot water or hot metal to an animal's skin surface is often used to prepare burn wound models. However, manual burn creation is subject to human variability.We developed a new device that can control the temperature, time, and pressure of contact to produce precise and reproducible animal burn wounds and investigated the conditions required to prepare various burn wounds using our new device. Methods: We prepared burnwounds on F344 rats using 3 contact times 2, 4, and 10 seconds using a stamp heated to 80C. We observed the wound-healing process macroscopically and histologically and evaluated the burn depth using a laser speckle contrast-imaging device, which evaluated the blood flow of the wound. Results: The changes in the burned area over time, tissue perfusion of the burn wounds, histological evaluation of the burn depth by hematoxylin-eosin and azocarmine and aniline blue staining, and the epithelialization rate (the ratio of the epithelialized area to the wound length) were evaluated on histological sections. Results indicated that the burn wounds prepared with contact times of 2, 4, and 10 seconds corresponded to superficial dermal burns, deep dermal burns, and full-thickness burns, respectively. Conclusions: We demonstrated that partial-and full-thickness burn wounds can be precisely and reproducibly created with our new automated burning device