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Nocturnal moths evolved ultrasound-triggered escape maneuvers for avoiding predatory bats emitting ultrasonic echolocation calls. Using ultrasound for pest control is not a novel concept, but the technique has not been systemized because of the moths’ habituation to sounds and the narrow directionality of conventional ultrasound speakers. Here, we report the use of pulsed ultrasonic white noise, which contributes to achieving ecologically concordant plant protection. An ultrasonic pulse, which is temporal mimicry of the search-phase pulse in the echolocation calls of a sympatric bat, was identified using neuroethological screening of eared moth–repelling ultrasounds; these pulses elicit flight-stopping reactions in moths but have no or little auditory adaptation. Such repellent ultrasounds broadcast from the cylindrical omni-azimuth ultrasound emitters suppressed the intrusion of gravid females of pest moths into cultivation fields. Thus, egg numbers and plant damage by hatched larvae were drastically reduced, enabling farmers to substantially skip applications of chemical insecticides for controlling moth pests.

Base-stabilized neutral oxoborane and thioxoborane supported by a bis(oxazolinyl)(phenyl)methanide ligand have been synthesized and structurally characterized. While previous synthetic attempts of oxoborane ligated by β-diketiminate (NacNac) did not allow for its isolation in acid-free form, oxoborane supported by a bis(oxazolinyl)(phenyl)methanide ligand is isolable, due to the absence of imine ɑ-protons and steric protection of enamine carbon. Crystallographic analysis revealed the presence of a B-O double bond close to the shortest end of the reported lengths. Its reactivity has also been examined, and it was majorly governed by the nucleophilicity and basicity of the oxygen atom. The chemical inertness and synthetic convenience of the bis(oxazolinyl)(phenyl)methanide scaffold presented in this work suggest its utility as an innocent alternative to the NacNac scaffold.

This work reports the design and synthesis of a series of 5-membered and 6-membered N-hydroxyimides flanked by lipophilic alkyl groups adjacent to carbonyl groups, aiming to endow lipophilicity and tolerance toward ring opening degradation. Their solubility in cyclohexane was 5-20 times higher than those of unsubstituted N-hydroxyphthalimide (NHPI) and even 3-10 times higher than a formerly known lipophilic NHPI analog bearing a long alkyl ester. UV-Vis spectroscopy determined the rate constants of first-order decay of N-oxyls, which revealed enhanced stability of 3,5-di-tert-butyl-NHPI and N-hydroxyglutarimide flanked by spiro-cyclohexanes compared with that of NHPI. Their bond dissociation energies were assessed by EPR spectroscopy and DFT calculation, suggesting these lipophilic N-hydroxyimides catalyzed aerobic cyclohexane oxidation under neat conditions with up to 60 turnovers, which is the highest among hitherto reported reactions under neat conditions.

Rhodium-catalyzed acrylate synthesis from CO

Reaction of an Al-centered anion with toluene proceeded to form C-H cleaved product with a perfect meta -selectivity and a relatively small kinetic isotope effect (KIE, k H / k D = 1.51). DFT calculations suggested a two-step reaction mechanism and electronically controlled meta -selectivity arising from the electron-donating methyl group. The reaction with other mono-substituted arenes was also investigated.

Industrial monitoring systems are developed and deployed to continuously and remotely monitor the status of industrial equipment and detect failures. A gateway node collects status data from sensors attached to machines and then sends them to a server for analysis and evaluation. In this paper, we propose a method to detect anomalies in communication between a gateway and a server over an LTE network, whose failure would bring a serious result such as an operation halt of the whole factory. We model a time series of dynamically and instantaneously changing response delay as sawtooth waves and detect an anomaly based on their statistical characteristics. Through evaluations using real measurements and artificial data, we verified that our method can detect both of constant increase and decrease, rapid increase, long-term increase, and slow decrease in the response delay.

Coevolutionary adaptation leads to modifications of sensory physiology and behavioral responses of predators and prey. From the ecological point of view, insect hearing and acoustic behavior are an attractive study area for researchers in entomology, animal behavior, and neuroethology. Recent technical advances in sound-recording equipment and molecular techniques have contributed to understanding the evolution of acoustic communication, including sexual dialogue, intraspecific competition, and the interspecific arms race between predators (e.g., bats) and prey (e.g., moths). Singing male moths exploit ultrasound-induced freezing responses of potential female mates or unwelcome rival males to enhance mating success. Freezing responses to ultrasound by moths are originally an antipredator reaction to echolocating insectivorous bats. The aim of Chap. 5 is to provide a sensory-behavioral explanation of the freezing response of insects during predator–prey interaction.

Reaction of an Al-centered anion with toluene proceeded to form C-H cleaved product with a perfect meta-selectivity and a relatively small kinetic isotope effect (KIE, k

We carried out a study on medical diagnosis automation by ultrasound B-mode video. The video current doctor is using. Our study aims to devise a quantitative evaluation method that monitors the degree of activity in the body, especially the small intestine. We believe that the moving image tracking technology can indicate the degree of activity. However, the object reflected in the ultrasonic moving image does not exhibit a contour pattern, and the magnitude varies dramatically. Objects of irregular shape, such as the shapes and patterns of an object by such time changes cannot be tracked using existing technology. The present study developed a computational method for tracking the moving image of such an object, and performed a simulation. In the calculation, we used the theory of "multidimensional directed amount of information".

This study investigated the corrosion behavior of the corrosion-resistant films steam coated on AZCa612 magnesium alloy. The film samples were corroded by immersing them in 5 wt% NaCl aqueous solution for a predetermined time. The corroded films were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, glancing angle X-ray diffraction, Fourier transform infrared spectroscopy, potentiodynamic polarization measurements, hydrogen generation measurements, and electrochemical impedance spectroscopy. The amount of Mg–Al–CO3 layered double hydroxides (LDHs) in the film slightly decreased from the beginning of immersion to 120 h after immersion and gradually increased thereafter. Mg–Al–Cl LDHs were formed after 6 h of immersion and rapidly grew as the immersion progressed. In addition, even with the gradual decrease in the corrosion resistance of the film, there was no major damage observed on the substrates. These results indicate that the corrosion protection mechanism varied with the immersion time. The corrosion-resistant property under a short immersion time could be attributed to the high corrosion resistance of Mg(OH)2 and AlO(OH), whereas it is attributed to the coverage provided by the Mg–Al–Cl and Mg–Al–CO3 LDHs under a longer immersion duration.

Aims: The influence of lifestyle-related factors, including smoking and drinking, was evaluated for Helicobacter pylori eradication therapy with vonoprazan or proton pump inhibitors (PPIs). Methods: Between 2012 and 2016, the medical records of 620 patients receiving H. pylori eradication therapy at Saiseikai Karatsu Hospital were evaluated. Patients had received vonoprazan (20 mg) or PPIs with 200 mg clarithromycin and 750 mg amoxicillin twice daily for 7 days. The influence of lifestyle-related factors on eradication failure was determined in the 2 groups. Results: The eradication rates for vonoprazan and lansoprazole, rabeprazole, and esomeprazole were, respectively, 91.0, 73.8, 72.0, and 84.6%. The vonoprazan eradication rate was significantly higher than those for the PPIs (p < 0.01). Habitual smoking and drinking did not increase eradication failure, and smoking and drinking during the eradication period did not reduce the eradication rate. Metabolic syndrome-related factors including obesity, hypertension, and diabetes mellitus had no negative influence on the eradication rate. Eradication with vonoprazan was more effective compared with that achieved through the use of PPIs. Conclusion: Lifestyle-related factors including smoking and drinking did not exacerbate the H. pylori eradication failure, and vonoprazan was more effective than the PPIs.

The reactivity of dialkylalumanyl anion (1) towards naphthalene, anthracene, diphenylacetylene, and (E)/(Z)‐stilbenes was investigated. The compound 1 reacts with naphthalene and anthracene through (1+4) cyclization, giving Al‐containing norbornadiene derivatives. In the reaction of 1 with diphenylacetylene and (E)/(Z)‐stilbenes, (1+2) cyclization proceeded to form Al‐C‐C three‐membered rings. Cyclization toward (E)‐ or (Z)‐stilbenes solely gave a trans ‐cycloadduct. DFT calculations revealed that the cycloaddition of 1 with (Z)‐stilbene proceeds via a single transition state with a carbanion character, which results in the selectivity towards the trans ‐cycloadduct., ファイル公開：2021-02-17

A saturated N-heterocyclic carbene–phenolate bidentate ligand, 3,3a,4,5-tetrahydroimidazo[1,5-a]quinolin-9-olate-1-ylidene (SIzQO), was synthesized and characterized. The SIzQO ligand was then treated with PdClMe(pyridine)2 and [Pd(μ-Cl)Me(2,6-lutidine)]2, which afforded C,C-cis-(SIzQO)PdMe(pyridine) and the thermodynamically unstable trans isomer C,C-trans-(SIzQO)PdMe(2,6-lutidine), respectively. The latter isomerizes at 40 °C into the corresponding cis isomer via a dissociative mechanism. These palladium/SIzQO complexes catalyze the polymerization of ethylene at 100–120 °C, although the catalytic activity is lower than that of a previously reported palladium/imidazo[1,5-a]quinolin-9-olate-1-ylidene (IzQO) system.

Coordination–insertion copolymerization of ethylene with 1,1-disubstituted ethylenes bearing a polar functional group, such as me-thyl methacrylate (MMA), is a long-standing challenge in catalytic polymerization. The major obstacle for this process is the huge difference in reactivity of ethylene versus 1,1-disubstituted ethylenes towards both coordination and insertion. Herein we report the copolymerization of ethylene and 1,1-disubstituted ethylenes by using an imidazo[1,5-a]quinolin-9-olate-1-ylidene (IzQO)-supported palladium catalyst. Various types of 1,1-disubstituted ethylenes were successfully incorporated into the polyethylene chain. In-depth characterization of the obtained copolymers and mechanistic inferences drawn from stoichiometric reactions of alkylpalladium com-plexes with methyl methacrylate and ethylene indicate that the copolymerization proceeds by the same coordination–insertion mech-anism that has been postulated for ethylene.

We report the synthesis and characterisation of palladium complexes bearing an N-heterocyclic carbene–phosphine oxide bidentate ligand and their use as catalysts for ethylene polymerisation and ethylene/polar monomer copolymerisation.

The Industrial Internet of Things (IIoT) applications are required to provide precise measurement functions as feedback for controlling devices. The applications traditionally use polling-based communication protocols. However, in polling-based communication over current industrial wireless network protocols such as ISA100.11a, WirelessHART have difficulty in realizing both scheduled periodic data collection at high success ratio and unpredictable on-demand communications with short latency. In this paper, a polling-based transmission scheme using a network traffic uniformity metric is proposed for IIoT applications. In the proposed scheme, a center node controls the transmission timing of all polling-based communication in accordance with a schedule that is determined by a Genetic Algorithm. Communication of both periodic and unpredictable on-demand data collection are uniformly assigned to solve the above difficulties in the schedule. Simulation results show that network traffic is generated uniformly and a center node can collect periodic data from nodes at high success ratio. The average success probability of periodical data collection is 97.4 % and the lowest probability is 95.2 % .

The mechanism of linear polyethylene formation catalyzed by palladium/phosphine−sulfonate and the effect of the ligand structure on the catalytic performance, such as linearity and molecular weight of the polyethylene, were reinvestigated theoretically and experimentally. We used dispersion-corrected density functional theory (DFT-D3) to study the entire mechanism of polyethylene formation from (R2PC6H4SO3)PdMe(2,6-lutidine) (R = Me, t-Bu) and elucidated the key steps that determine the molecular weight and linearity of the polyethylene. The alkylpalladium ethylene complex is the key intermediate for both linear propagation and β-hydride elimination from the growing polymer chain. On the basis of the key species, the effects of substituents on the phosphorus atom (R = t-Bu, i-Pr, Cy, Men, Ph, 2-MeOC6H4, biAr) were further investigated theoretically to explain the experimental results in a comprehensive manner. Thus, the experimental trend of molecular weights of polyethylene could be correlated to the ΔΔG...

The replacement of precious metals in catalysis by earth-abundant metals is currently one of the urgent challenges for chemists. Whereas palladium-catalyzed copolymerization of ethylene and polar monomers is a valuable method for the straightforward synthesis of functionalized polyolefins, the corresponding nickel-based catalysts have suffered from poor thermal tolerance and low molecular weight of the polymers formed. Herein, we report a series of neutral nickel complexes bearing imidazo[1,5-a]quinolin-9-olate-1-ylidene (IzQO) ligands. The Ni/IzQO system can catalyze ethylene polymerization at 50-100 °C with reasonable activity in the absence of any cocatalyst, whereas most known nickel-based catalysts are deactivated at this temperature range. The Ni/IzQO catalyst was successfully applied to the copolymerization of ethylene with allyl monomers to obtain the corresponding copolymers with the highest molecular weight reported for a Ni-catalyzed system.

The reduction of CO2 into formic acid or its conjugate base, using dihydrogen, is an attractive process. While catalysts based on noble metals have shown high turnover numbers, the use of abundant first-row metals is underdeveloped. The key steps of the reaction are CO2 insertion into a metal hydride and regeneration of the metal hydride with H2, along with the concomitant production of formate. For the first step, copper is known as one of the most efficient metals, as shown by the numerous copper-catalysed carboxylation reactions, but this metal has difficulties activating H2 to achieve the second step. Here, we report a catalytic system involving a stable copper hydride that activates CO2, working in tandem with a Lewis pair that heterolytically splits H2. In this system, unprecedented turnover numbers for copper are obtained. Surprisingly, through a combination of stoichiometric and catalytic reactions, we show that classical Lewis pairs outperform frustrated Lewis pairs in this process. Due to its ready availability and low cost, copper is an attractive metal for the homogeneous reduction of CO2 to formate. However, although CO2 can readily insert into copper hydrides to produce metal-bound formate, subsequent regeneration of the catalytic species with H2 is more challenging. Here a dual strategy is used, whereby a copper hydride activates CO2 and a Lewis pair heterolytically splits H2, leading to dramatically improved performance.

Background: Leukocyte removal therapy (LRT) is an effective treatment for active ulcerative colitis (UC). The present study was performed to evaluate the relapse-free period after LRT and identify risk factors for relapse. Methods: In total, 94 patients who underwent first-time LRT for remission of moderate to severe UC from April 2004 to March 2016 were enrolled in the present study. The patients were randomly assigned to one of 2 treatments: leukocytapheresis (LCAP; n = 43) or granulocyte and monocyte/macrophage adsorptive apheresis (GMA; n = 51). The 5-year cumulative relapse-free rate and risk factors for relapse were evaluated. Results: The therapeutic response rate was 82% for GMA and 70% for LCAP without a statistically significant difference. The 5-year relapse-free rate was 34.7% in the LRT group. The 5-year relapse-free rate in patients aged > 40 years was 49.9%, which was significantly higher than that in patients aged ≤40 years (22.9%, p < 0.01). The relapse-free period was longer in the older than younger patients. Conclusions: The relapse-free period after LRT was examined in patients with UC, and 34.7% of patients achieved clinical remission within a 5-year period. The risk factor for early relapse after LRT was younger age.

The influence of lifestyle-related factors, including smoking and drinking, was evaluated for Helicobacter pylori eradication therapy with vonoprazan or proton pump inhibitors (PPIs).Between 2012 and 2016, the medical records of 620 patients receiving H. pylori eradication therapy at Saiseikai Karatsu Hospital were evaluated. Patients had received vonoprazan (20 mg) or PPIs with 200 mg clarithromycin and 750 mg amoxicillin twice daily for 7 days. The influence of lifestyle-related factors on eradication failure was determined in the 2 groups.The eradication rates for vonoprazan and lansoprazole, rabeprazole, and esomeprazole were, respectively, 91.0, 73.8, 72.0, and 84.6%. The vonoprazan eradication rate was significantly higher than those for the PPIs (p0.01). Habitual smoking and drinking did not increase eradication failure, and smoking and drinking during the eradication period did not reduce the eradication rate. Metabolic syndrome-related factors including obesity, hypertension, and diabetes mellitus had no negative influence on the eradication rate. Eradication with vonoprazan was more effective compared with that achieved through the use of PPIs.Lifestyle-related factors including smoking and drinking did not exacerbate the H. pylori eradication failure, and vonoprazan was more effective than the PPIs.

By flanking a carbene carbon with two substituents, it is possible to synthesize persistent triplet carbenes and isolable singlet carbenes. Isolable singlet carbenes are among the most powerful tools in chemistry, and they have even found medicinal and materials science applications. Between the rich chemistry of disubstituted carbenes and the transient parent carbene are the monosubstituted carbenes that, so far, have only been observed in matrices at very low temperatures of just a few K. Herein, we describe the synthesis of a crystalline monosubstituted carbene. The key for isolating such a species was to design the correct substituent, namely a benzo[c]pyrrolidino heterocycle, which can single-handedly tame the intrinsic tendency of carbenes towards dimerization. The π-donor ability of the nitrogen atom, coupled with the steric bulk of chemically inert substituents at the two adjacent quaternary carbons, make these scaffolds very attractive for the isolation of a variety of other hitherto elusive electron-deficient species.

The graft density dependence of main chain stiffness in rod brushes composed of a flexible linear polystyrene (PS) main chain and poly(n-hexyl isocyanate) (PHIC) rod side chains has thoroughly been investigated by static light (LS) and small-angle X-ray scattering (SAXS) measurements in tetrahydrofuran (THF) at 25 °C. A series of statistical graft copolymers having different graft densities (σ) and graft chain lengths (PS-g-HIC-Ns-lg, where Ns is the weight-averaged degree of polymerization of HIC and lg is the average distance (spacing) of the main chain between the side chain joints) were prepared by the nearly azeotrope radical copolymerizations of styrene (M1) with PHIC macromonomers (M2) (r1 = 0.84 ± 0.1 and r2 = 1.1 ± 0.3) in n-hexane or the bulk at 60 °C. The compositional heterogeneities of the graft copolymers were carefully characterized by the ratio of the UV to RI signal in the SEC traces and the comparison with those predicted from the theory by Stejskal and Kratochvil [Macromolecules 1987, 2...