Optimal Rendezvous L-Algorithms for Asynchronous Mobile Robots with External-Lights

We study the Rendezvous problem for two autonomous mobile robots in asynchronous settings with persistent memory called light. It is well known that Rendezvous is impossible in a basic model when robots have no lights, even if the system is semi-synchronous. On the other hand, Rendezvous is possible if robots have lights of various types with a constant number of colors. If robots can observe not only their own lights but also other robots\u27 lights, their lights are called full-light. If robots can only observe the state of other robots\u27 lights, the lights are called external-light. This paper focuses on robots with external-lights in asynchronous settings and a particular class of algorithms called L-algorithms, where an L-algorithm computes a destination based only on the current colors of observable lights. When considering L-algorithms, Rendezvous can be solved by robots with full-lights and three colors in general asynchronous settings (called ASYNC) and the number of colors is optimal under these assumptions. In contrast, there exist no L-algorithms in ASYNC with external-lights regardless of the number of colors. In this paper, extending the impossibility result, we show that there exist no L-algorithms in so-called LC-1-Bounded ASYNC with external-lights regardless of the number of colors, where LC-1-Bounded ASYNC is a proper subset of ASYNC and other robots can execute at most one Look operation between the Look operation of a robot and its subsequent Compute operation. We also show that LC-1-Bounded ASYNC is the minimal subclass in which no L-algorithms with external-lights exist. That is, Rendezvous can be solved by L-algorithms using external-lights with a finite number of colors in LC-0-Bounded ASYNC (equivalently LC-atomic ASYNC). Furthermore, we show that the algorithms are optimal in the number of colors they use

A novel homozygous variant of the thrombomodulin gene causes a hereditary bleeding disorder

ArticleBlood Advances. 5(19): 3830-3838 (2021)journal articl

HETEROTACTIC POLY(N-ISOPROPYLACRYLAMIDE)

Radical polymerization of N-isopropylacrylamide (NIPAAm) in toluene at low temperatures, in the presence of fluorinated alcohols, produced heterotactic polymer comprising an alternating sequence of meso and racemo dyads. The heterotacticity reached 70% in triads when polymerization was carried out at –40°C using nonafluoro-tert-butanol as the added alcohol. NMR analysis revealed that formation of a 1:1 complex of NIPAAm and fluorinated alcohol through C=O•••H-O hydrogen bonding induces the heterotactic specificity. A mechanism for the heterotactic-specific polymerization is proposed. Examination of the phase transition behavior of aqueous solutions of heterotactic poly(NIPAAm) revealed that the hysteresis of the phase transition between the heating and cooling cycles depended on the average length of meso dyads in poly(NIPAAm)

Effects of Variation in Cushion Thickness on the Sit-to-Stand Motion of Elderly People

This study was done to investigate whether cushion thickness affected elderly people during the sit-to-stand motion (STS motion). Fourteen elderly subjects aged 79 or over were recruited from the outpatients at a rehabilitation clinic. Their STS motions were evaluated and analyzed using a digital video camera and analyzing software. As the thickness of the cushion increased, it was difficult to identify the pelvic movement during STS motion, although the trunk was inclined more anteriorily and the load to the knee extensors was greater. Furthermore, three of the fourteen subjects had difficulties performing STS motion when the pelvis was contoured by a thick cushion. These results suggests that if an older person has a knee extensor strength below an appropriate level and/or the cushion thickness is enough large to contour the subject’s pelvis, the risk of falling during STS motion is higher

Smart Integrated Sensor for Multiple Detections of Glucose and L-Lactate Using On-Chip Electrochemical System

Multiple sensor electrodes, a supplementary electrode, a reference electrode, and signal-processing circuits were integrated on a single chip to develop a chip-shaped electrochemical sensing system. L-lactate and glucose were measured using on-chip working electrodes modified by polyion complex to immobilize lactate oxidase and glucose oxidase, respectively. Cyclic voltammetry measurements were conducted using an on-chip potentiostat. Selective and quantitative detection of glucose and L-lactate and the interference behavior were studied. Hydrogen peroxide generated by enzymatic reactions was detected by an increase in anodic oxidation current. Reaction currents at +0.7 V versus Ag/AgCl were used to obtain calibration plots. The measured dynamic ranges for L-lactate and glucose were 0.2–1.0 mM and 2.0–8.0 mM, respectively. The sensitivities were 65 nA/mM and 15 nA/mM, respectively, using a working electrode of 0.5 mm2. The 3σ detection limit was 0.19 mM and 1.1 mM, respectively. We have achieved multiple biomaterial detections on a circuit-equipped single chip. This integrated electrochemical sensor chip could be the best candidate for realizing point-of-care testing due to its portability and potential for mass production

National survey of catheter ablation for atrial fibrillation: The Japanese catheter ablation registry of atrial fibrillation (J-CARAF)

AbstractTo assess the current status of atrial fibrillation (AF) ablation in Japan, the Japanese Heart Rhythm Society (JHRS) instituted a national registry, the Japanese Catheter Ablation Registry of AF (J-CARAF).MethodsUsing an online questionnaire, the JHRS invited electrophysiology centers in Japan to voluntarily and retrospectively register data regarding the AF ablation procedures performed in September, 2011.ResultsA total of 128 centers submitted data regarding AF ablation procedures in 932 patients (age 62.1±10.4 years; male 76.8%; paroxysmal AF 65.7%, CHADS2 score 1.0±1.0). The majority received oral anticoagulant therapy during and following the procedure (68.9% and 97.5%, respectively). Pulmonary vein isolation (PVI) was performed in 97.5% of the patients; ipsilateral encircling PVI was the preferred technique (79.7%). Three-dimensional (3D) mapping systems and irrigated-tip catheters were used in 94.8% and 87.7% of the procedures, respectively. Ablation methods other than PVI were performed in 78.8% of all the patients and 73.5% of the patients with paroxysmal AF. Acute complications were reported in 6.2% of the patients, but no early deaths were recorded.ConclusionsIpsilateral encircling PVI, using 3D mapping and irrigated-tip catheters, is the standard AF ablation method in Japan. However, adjunctive ablations were performed frequently, even in patients with paroxysmal AF

Low-dose irradiation promotes tissue revascularization through VEGF release from mast cells and MMP-9–mediated progenitor cell mobilization

Mast cells accumulate in tissues undergoing angiogenesis during tumor growth, wound healing, and tissue repair. Mast cells can secrete angiogenic factors such as vascular endothelial growth factor (VEGF). Ionizing irradiation has also been shown to have angiogenic potential in malignant and nonmalignant diseases. We observed that low-dose irradiation fosters mast cell–dependent vascular regeneration in a limb ischemia model. Irradiation promoted VEGF production by mast cells in a matrix metalloproteinase-9 (MMP-9)–dependent manner. Irradiation, through MMP-9 up-regulated by VEGF in stromal and endothelial cells, induced the release of Kit-ligand (KitL). Irradiation-induced VEGF promoted migration of mast cells from the bone marrow to the ischemic site. Irradiation-mediated release of KitL and VEGF was impaired in MMP-9–deficient mice, resulting in a reduced number of tissue mast cells and delayed vessel formation in the ischemic limb. Irradiation-induced vasculogenesis was abrogated in mice deficient in mast cells (steel mutant, Sl/Sld mice) and in mice in which the VEGF pathway was blocked. Irradiation did not induce progenitor mobilization in Sl/Sld mice. We conclude that increased recruitment and activation of mast cells following irradiation alters the ischemic microenvironment and promotes vascular regeneration in an ischemia model. These data show a novel mechanism of neovascularization and suggest that low-dose irradiation may be used for therapeutic angiogenesis to augment vasculogenesis in ischemic tissues