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Frogs are a representative taxon that use advertisement calls to aid in reproduction. In most frog species, calls vary with body size, and allometric constraints between body size and call frequency have been widely reported among anuran species. Although this variation is an important driver of sexual selection in frogs, male advertisement call strategies may also vary according to body size. In this study, we conducted playback experiments on the male forest green tree frog (Zhangixalus arboreus) to determine whether male advertisement call characteristics and strategies vary according to body size and the amplitude of intraspecific chorus noise. The results indicated that the calls of larger individuals are louder and lower than those of smaller ones, who call more frequently; moreover, the calls become lower, and the number of calls decreases, as noise levels increase. These findings suggest that forest green tree frog emits lower calls or refrains from calling when chorus noise increases, and that intraspecific variation in advertisement call characteristics can induce different strategies in response to chorus noise. Because advertisement call variation with body size is common among frog species, intraspecific variation in male advertisement call strategies may also be a common phenomenon. [ABSTRACT FROM AUTHOR]

The redox behaviors of macrocyclic molecules with an entirely π-conjugated system are of interest due to their unique optical, electronic, and magnetic properties. In this study, defect-free cyclic P3HT with a degree of polymerization (DPn) from 14 to 43 was synthesized based on our previously established method, and its unique redox behaviors arising from the cyclic topology were investigated. Cyclic voltammetry (CV) showed that the HOMO level of cyclic P3HT decreases from –4.86 eV (14 mer) to –4.89 eV (43 mer), in contrast to the linear counterparts increasing from –4.94 eV (14 mer) to –4.91 eV (43 mer). During the CV measurement, linear P3HT suffered from electro-oxidation at the chain ends, while cyclic P3HT was stable. ESR and UV–Vis–NIR spectroscopy suggested that cyclic P3HT has stronger dicationic properties due to the interactions between the polarons. On the other hand, linear P3HT showed characteristics of polaron pairs with multiple isolated polarons. Moreover, the dicationic properties of cyclic P3HT were more pronounced for the smaller macrocycles. [ABSTRACT FROM AUTHOR]

Formate dehydrogenase from Candida boidinii (CbFDH) reversibly catalyzes formate to CO2 with the redox couple NAD+/NADH. While many studies on CbFDH-catalyzed formate oxidation in the presence of NAD+ are reported, there are few studies on the detailed mechanism of the CbFDH-catalyzed CO2 reduction in the presence of NADH. In this study, the detailed mechanism of formate production by CbFDH with NADH in GTA buffer solution (consisting of 3,3-dimethylglutaric acid, tris(hydroxymethyl)aminomethane and 2-amino-2-methyl-1,3-propanediol) with different proportions of CO2, bicarbonate and carbonate was studied. A good correlation was found between the pH of the buffer solution, the CO2 concentration and the apparent initial rate of formate production with CbFDH. Under constant conditions of total carbonate concentration in the buffer solution, the process of the CbFDH-catalyzed reduction of CO2 to formate followed the Michaelis–Menten kinetics. Particularly, the reaction rate of formate production with CbFDH increased with increasing CO2 concentration under constant conditions of total carbonate concentration in the solution. As the apparent formate production rate with CbFDH increases under higher total carbonate concentration, bicarbonate or carbonate does not act as a competitive inhibitor of CO2, and it is predicted that the CO2 concentration equivalent consumed in the CbFDH-catalyzed formate production is supplied by bicarbonate or carbonate by the pH control function of the GTA buffer solution. Thus, we have clarified for the first time that these carbonates do not function as any inhibitor for the CbFDH-catalyzed CO2 reduction. [ABSTRACT FROM AUTHOR]

Arthroscopic debridement for elbow osteoarthritis has been widely used as a minimally invasive treatment; however, in some cases, it can be a technically demanding procedure, such as in patients with severe osteoarthritis with large spur formation and severe synovitis. The anterocentral transbrachialis portal is a recently developed portal for elbow arthroscopy, which allows easy and convenient access to the anterior compartment for sufficient debridement. This report describes in detail the anterocentral transbrachialis portal and its usefulness for debridement of the elbow joint in osteoarthritis. [Display omitted] [ABSTRACT FROM AUTHOR]

Formate dehydrogenase from Candida boidinii (CbFDH) reversibly catalyzes formate to carbon dioxide with the redox couple NAD+/NADH. There have been many studies on CbFDH-catalyzed oxidation of formate to carbon dioxide in the presence of NAD+. On the other hand, there are few studies on the detailed mechanism of the carbon dioxide reduction to formate catalyzed by CbFDH in the presence of NADH. In addition, it is not clear whether CbFDH can reduce carbon dioxide, bicarbonate or carbonate to formate. In this study, formate production with CbFDH in the presence of NADH was investigated in solutions with different ratios of carbon dioxide, bicarbonate and carbonate. The reaction rate of formate production with CbFDH increased in proportion to the concentration of carbon dioxide in the reaction solution. On the other hand, the formate production with CbFDH was suppressed in proportion to the concentration of bicarbonate or carbonate in the reaction solution. Thus, CbFDH was found to catalytically reduce only carbon dioxide to formate among the three types of carbonate species. [ABSTRACT FROM AUTHOR]

A number of methods have been proposed for the response-time analysis (RTA) of controller area networks (CANs), which are the industry standard for in-vehicle network protocols. However, most of these methods are unsuitable for analyzing nonperiodically transmitted messages because they assume a constant transmission period for each message. Moreover, the calculated evaluation criteria are limited and comprise many over-pessimistic estimations, such as the worst-case response time (WCRT). To tackle these problems, this paper proposes an RTA method for CANs with randomly occurring messages, which replaces the constant transmission period with the average number of transmission instances per unit time. This approach finds the approximate probability distribution of the response time to any message in a CAN, providing a more general measure than the WCRT. To this end, a mathematical model based on M/G/1 queueing theory is developed. The model accurately emulates the behavior of nonperiodic CAN messages and enables RTA with minimal pessimistic estimations. When tested against the benchmarks, the proposed method accurately obtained response time distributions within several seconds to several tens of seconds. [ABSTRACT FROM AUTHOR]

Purpose: In an effort to assess the characteristics of mutation induced by different linear energy transfer (LET) radiation in higher plants, the mutational effects of carbon-ion beams and γ-rays were investigated in Arabidopsis. Materials and methods: The rpsL ( Escherichia coli ribosomal protein small subunit S12) transgenic Arabidopsis (Arabidopsis/rpsL) mutation detection system was adopted. Dry seeds of Arabidopsis/rpsL were irradiated with γ-rays and 208-MeV carbon ions (208-MeV 12C5+), and the mutation frequency and mutation spectrum were examined. Results: The frequency of mutant clones increased following irradiation with 208-MeV 12C5+ and γ-rays. Mutation spectrum analysis showed that G:C to A:T transitions and >2 bp deletions/insertions were significantly induced by both 208-MeV 12C5+ and γ-rays. −1 and −2 frameshift mutations were characteristic in the γ-ray irradiated group. Conclusions: 208-MeV 12C5+ and γ-rays induced different intragenic mutations in respect to the size of deletions, reflecting differences in the nature of the DNA damage induced. Our results also suggested that base substitutions derived from the generation of 8-oxoguanine were low in dry seeds. The mutation spectrum obtained in this study might have reflected the characteristic conditions of plant dry seeds such as low water content and cell proliferation activity. [ABSTRACT FROM AUTHOR]

This paper describes the utilization of the downwashes of multicopters for gas-sensing applications. Multirotor drones are an attractive platform for sensing applications. Their high maneuverability enables swift scanning of a target area with onboard sensors. When equipped with a gas sensor and used for gas-sensing applications, however, the strong downwash produced by the rotors poses a problem. When a multicopter is hovering at a low altitude, gas puffs leaked from a gas source on the ground are all blown away. Here, we propose to use two multicopters connected by a rod or a string and place a gas sensor at the midpoint of the rod/string. The downwash generated by each multicopter spreads radially after it impinges on the ground. When two multicopters are connected, the airflows spreading radially along the ground from the two multicopters impinge at the center and are deflected in the upward direction. Gas puffs wafting near the ground surface between the two multicopters are carried by this upward airflow to the gas sensor. Experimental results are presented to show the soundness of the proposed method. The connected quadcopters hovering over an ethanol gas source was able to detect the gas even with a moderate cross-flow. [ABSTRACT FROM AUTHOR]