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Autonomous capabilities could be an essential aspect of future near-Earth asteroid exploration missions, enabling a fleet of low-cost spacecraft to be distributed to various targets for increased scientific and engineering returns. This paper studies the design of an adaptive offline policy for a surface imaging task under the influence of maneuver noise via reinforcement learning (RL). An adaptive policy that responds to the changes in the environment is obtained by including asteroid parameters as part of the feedback state and randomizing them during the training. The proximal policy optimization algorithm is used to train the policy. The robustness of the policy is tested in an environment that has unmodeled dynamical effects. Further, the overall performance of the autonomous exploration scheme is studied by combining the RL-based policy with the previously proposed autonomous navigation strategy that is built around optical and [Formula: see text] measurements. The end-to-end simulations that combine both onboard navigation and guidance are performed using asteroid Bennu as an example target, and the results show that the proposed scheme is robust.

We report critical impacts of local and nonlocal geometries of plasmonic tips on the broadband nonlinear optical responses in tip-substrate nanocavities. Using gold tips with varied geometries, we demonstrated for the first time that not only the nanometer-scale sharpness of tip apexes but also the micrometer-scale surface geometry of tip shafts directly affects the enhancement properties of second-harmonic generation over the visible-to-infrared wavelength range. Numerical simulations of plasmonic field in the tip-substrate nanocavities revealed concerted contributions from spatially nonlocal and local plasmonic modes. Micrometer-scale tip shafts enable the excitation of nonlocal plasmonic modes throughout the tip, enhancing near-to-mid-infrared incoming light. Subsequent radiation of visible-to-near-infrared second harmonics is predominantly boosted by localized plasmons at the nanogap. Based on the agreement between experiments and calculations, our results indicate the importance of nanometer- and micrometer-scale geometrical engineering of plasmonic tips and provide a firm basis for the understanding and fine manipulation of nonlinear optical phenomena in tip-substrate nanocavities.

We report critical impacts of local and nonlocal geometries of plasmonic tips on the broadband nonlinear optical responses in tip-substrate nanocavities. Using gold tips with varied geometries, we demonstrated for the first time that not only the nanometer-scale sharpness of tip apexes but also the micrometer-scale geometry of tip shafts directly affects the enhancement properties of second-harmonic generation over the visible-to-infrared wavelength range. Numerical simulations of the tip-substrate plasmonic field revealed concerted contributions from spatially nonlocal and local plasmonic modes. Micrometer-scale tip shafts enable the excitation of nonlocal plasmonic modes throughout the tip, enhancing near-to-mid-infrared incoming light. Subsequent radiation of visible-to-near-infrared second harmonics is boosted by localized plasmons at the nanogap. Based on the agreement between experiments and calculations, our results indicate the importance of nanometer- and micrometer-scale geometrical engineering of plasmonic tips and provide a firm basis to understand and finely manipulate nonlinear optical phenomena in tip-substrate nanocavities.

The details of incompatibility between aripiprazole (ARIP) oral solution and green tea were examined. When the ARIP oral solution was mixed with a commercial PET bottled green tea beverage, the residual rate of ARIP in the mixed solution decreased to 15.7-17.6%. Mixing with ARIP reduced the content of gallate-type green tea polyphenols (GTPs) in the mixed solution but not the content of non-gallate-type GTPs. Furthermore, using pH 3.0 lactic acid buffer, 2.23 mM ARIP solution and 2.23 mM GTP solution were prepared, and the same volumes of ARIP solution and GTP solution were mixed. When the gallate-type GTP solution was mixed, the residual rate of ARIP in the mixed solution decreased. On the other hand, when the non-gallate-type GTP solution was mixed, the residual rate of ARIP in the mixed solution did not decrease. From the above results, it was found that the main reason for the incompatibility between ARIP oral solution and green tea was the formation of an insoluble substance composed of ARIP and gallate-type GTPs in green tea. Furthermore, experimental results using the continuous variation method revealed that ARIP and (-)-epigallocatechin gallate, which is the most representative gallate-type GTP, interact at a molar ratio of 3 : 2.

An adequate system for triaging patients with head trauma in prehospital settings and choosing optimal medical institutions is essential for improving the prognosis of these patients. To our knowledge, there has been no established way to stratify these patients based on their head trauma severity that can be used by ambulance crews at an injury site.To develop a prehospital triage system to stratify patients with head trauma according to trauma severity by using several machine learning techniques and to evaluate the predictive accuracy of these techniques.This single-center retrospective cohort study was conducted by reviewing the electronic medical records of consecutive patients who were transported to Tokyo Medical and Dental University Hospital in Japan from April 1, 2018, to March 31, 2021. Patients younger than 16 years with cardiopulmonary arrest on arrival or with a significant amount of missing data were excluded.Machine learning-based prediction models to detect the presence of traumatic intracranial hemorrhage were constructed. The predictive accuracy of the models was evaluated with the area under the receiver operating curve (ROC-AUC), area under the precision recall curve (PR-AUC), sensitivity, specificity, and other representative statistics.A total of 2123 patients (1527 male patients [71.9%]; mean [SD] age, 57.6 [19.8] years) with head trauma were enrolled in this study. Traumatic intracranial hemorrhage was detected in 258 patients (12.2%). Among several machine learning algorithms, extreme gradient boosting (XGBoost) achieved the mean (SD) highest ROC-AUC (0.78 [0.02]) and PR-AUC (0.46 [0.01]) in cross-validation studies. In the testing set, the ROC-AUC was 0.80, the sensitivity was 74.0% (95% CI, 59.7%-85.4%), and the specificity was 74.9% (95% CI, 70.2%-79.3%). The prediction model using the National Institute for Health and Care Excellence (NICE) guidelines, which was calculated after consultation with physicians, had a sensitivity of 72.0% (95% CI, 57.5%-83.8%) and a specificity of 73.3% (95% CI, 68.7%-77.7%). The McNemar test revealed no statistically significant differences between the XGBoost algorithm and the NICE guidelines for sensitivity or specificity (P = .80 and P = .55, respectively).In this cohort study, the prediction model achieved a comparatively accurate performance in detecting traumatic intracranial hemorrhage using only the simple pretransportation information from the patient. Further validation with a prospective multicenter data set is needed.

Asteroid exploration missions must deal with large uncertainties in a target body’s gravity and shape as well as ephemeris errors upon rendezvous. Navigation and guidance are typically performed us...

The supporting effect of a N-doped carbon film induced superior crystallinity in electrodeposited Ni@Ni(OH)2 core–shell nanoparticles. This improvement resulted in a much higher regeneration rate of catalytic sites (NiOOH), leading to higher oxidation currents of sugars. Also, the overpotential of the maltopentaose (G5) oxidation reaction decreased significantly, probably due to the effect of the electrostatic interaction between NPs and G5.

Blind deconvolution is a technique to recover an original signal without knowing a convolving filter. It is naturally formulated as a minimization of a quartic objective function under some assumption. Because its differentiable part does not have a Lipschitz continuous gradient, existing first-order methods are not theoretically supported. In this paper, we employ the Bregman-based proximal methods, whose convergence is theoretically guaranteed under the $L$-smooth adaptable ($L$-smad) property. We first reformulate the objective function as a difference of convex (DC) functions and apply the Bregman proximal DC algorithm (BPDCA). This DC decomposition satisfies the $L$-smad property. The method is extended to the BPDCA with extrapolation (BPDCAe) for faster convergence. When our regularizer has a sufficiently simple structure, each iteration is solved in a closed-form expression, and thus our algorithms solve large-scale problems efficiently. We also provide the stability analysis of the equilibrium and demonstrate the proposed methods through numerical experiments on image deblurring. The results show that BPDCAe successfully recovered the original image and outperformed other existing algorithms.

Carbon materials have been widely used for electrochemical analysis and include carbon nanotubes, graphene, and boron-doped diamond electrodes in addition to conventional carbon electrodes, such as those made of glassy carbon and graphite. Of the carbon-based electrodes, carbon film has advantages because it can be fabricated reproducibly and micro- or nanofabricated into electrodes with a wide range of shapes and sizes. Here, we report two categories of hybrid-type carbon film electrodes for mainly electroanalytical applications. The first category consists of carbon films doped or surface terminated with other atoms such as nitrogen, oxygen and fluorine, which can control surface hydrophilicity and lipophilicity or electrocatalytic performance, and are used to detect various electroactive biochemicals. The second category comprises metal nanoparticles embedded in carbon film electrodes fabricated by co-sputtering, which exhibits high electrocatalytic activity for environmental and biological samples including toxic heavy metal ions and clinical sugar markers, which are difficult to detect at pure carbon-based electrodes.

Suitable orbit options around asteroids are limited due to strong perturbations caused by solar radiation pressure (SRP), a target’s irregular gravity field, and third-body acceleration. One potent...

Herein, an electrochemical method is presented for the detection of curcumin in food using a carbon nanotube (CNT)-carboxymethylcellulose (CMC) electrode. The CNT-CMC electrode exhibited ideal characteristics for curcumin detection, namely, a high response current and adequate peak separation toward curcumin oxidation. Cyclic voltammetry revealed two oxidation peaks. In the first scan, only the irreversible peak (Peak I) was observed at a higher potential. In the second scan, the reversible redox peak pairs (Peaks II and II') appeared at lower potentials, and the potential of Peak I was decreased. Peak I corresponded to oxidation of the hydroxyl groups of the benzene ring to the catechol group via a phenoxy radical, while Peaks II and II' indicated the redox loop system of the generated catechol group. The current at Peak II was used to quantify the concentration of curcumin in the linear range of 1 - 48 μM and detection limit of 0.084 μM. The concentrations of curcumin determined by the CNT-CMC electrode in real food samples were consistent with those determined by high-performance liquid chromatography.

The coupling between an electronic system and an environmental bath plays a decisive role in the excited state dynamics of artificial/natural molecular condensed phases. Although it is generally difficult to control the coupling between the system and the thermal bath in condensed matter, a strong light-matter coupling can control system-bath coupling properties using the polaron decoupling effect, in which a coherent interaction between excitons and photons reduces the reorganization energy. Here we demonstrate that this polaron decoupling strongly reduces the fluctuations in electronic energy in tetraphenyldibenzoperiflanthene thin films embedded in an optical microcavity. Using two-dimensional electronic spectroscopy, the frequency-fluctuation correlation function of the lower polariton state was revealed, showing that the dynamic inhomogeneity due to bath coupling inside the microcavity almost vanishes completely. This was attributed to a significant delocalization of the lower polariton state over 10

An electrochemical analysis using a multi-walled carbon nanotube (MWCNT) electrode is applied to examine chlorogenic acids (3-cafeoylquinic (3CQ), 4-cafeoylquinic (4CQ), 5-cafeoylquinic (5CQ), 3,4-dicafeoylquinic (34dCQ), 3,5-dicafeoylquinic (35dCQ), 4,5-dicafeoylquinic (45dCQ), 3-feruloylquinic (3FQ), 4-feruloylquinic (4FQ), and 5-feruloylquinic (5FQ) acid), which are the main ingredients of coffee polyphenols. The MWCNT electrode shows an excellent performance in the electrochemical quantification of chlorogenic acids. Cyclic voltammetry (CV) of all the chlorogenic acids shows redox peak pairs ranging between + 0.27 and + 0.31 V that are assigned to the redox reaction of the catechol group. Changes in the current due to individual chlorogenic acids at the peak potentials are proportional to their concentrations (3CQ, 4CQ, and 5CQ: linear range 0.4–194 μM, sensitivity 1.8 μA μM−1 cm−2; 34dCQ, 35dCQ, and 45dCQ: linear range 9.5–194 μM, sensitivity 4.3 μA μM−1 cm−2; and 3FQ, 4FQ, and 5FQ: linear range 5–194 μM, sensitivity 0.094 μA μM−1 cm−2). High-performance liquid chromatography (HPLC) analysis of coffee infusions shows that chlorogenic acids are almost entirely composed of 3CQ, 4CQ, and 5CQ. The total amounts of 3CQ, 4CQ, and 5CQ in coffee infusions obtained by HPLC show good agreement with those obtained by CV using the MWCNT electrode. This result indicates that the redox peak current can quantify the total amount of chlorogenic acid in a coffee infusion.

The mission of this chapter is to formalize multi-objective reinforcement learning (MORL) problems where there are multiple conflicting objectives with unknown weights. The objective is to collect all Pareto optimal policies in order to adapt them for use in a learner's situation. However, it takes huge learning costs in previous methods, so this chapter proposes the novel model-based MORL method by reward occurrence probability (ROP) with unknown weights. There are three main features. First one is that average reward of a policy is defined by inner product of the ROP vector and a weight vector. Second feature is that it learns the ROP vector in each policy instead of Q-values. Third feature is that Pareto optimal deterministic policies directly form the vertices of a convex hull in the ROP vector space. Therefore, Pareto optimal policies are calculated independently with weights and just one time by Quickhull algorithm. This chapter reports the authors' current work under the stochastic learning environment with up to 12 states, three actions, and three and four reward rules.

We demonstrate the electrochemical quantification of individual catechins (epicatechin, EC; epigallocatechin, EGC; epicatechingallate, ECG; and epigallocatechingallate, EGCG) in a green tea infusion without a separation process nor any adsorption complication. In the detection of catechins, long-length carbon nanotube (CNT)-carboxymethylcellulose (CMC) thin-film electrodes have attractive properties, such as well-defined current peaks, high reproducibility from sample to sample, high repeatability, and low background current. Cyclic voltammograms (CVs) for real green tea, which is mainly composed of a mixture of the four catechins, are produced by the sum of those catechins. A set of three specific peaks in the CVs of the real green tea samples, as catechin-mixture solutions, was used for quantification of the individual catechins. The CVs of the real samples are similar to the CVs of intentionally prepared mixture solutions with the catechin-component ratios determined by high-performance liquid chromatography (HPLC). The values for the real samples determined from the CVs show good agreement with those obtained by HPLC. The novelty of the work is the demonstration of the usefulness of the CNT-CMC electrode and the separationless quantification of individual catechins in green tea for the first time.

Difference of Convex (DC) optimization problems have objective functions that are differences between two convex functions. Representative ways of solving these problems are the proximal DC algorithms, which require that the convex part of the objective function have L-smoothness. In this article, we propose the Bregman Proximal DC Algorithm (BPDCA) for solving large-scale DC optimization problems that do not possess L-smoothness. Instead, it requires that the convex part of the objective function has the L-smooth adaptable property that is exploited in Bregman proximal gradient algorithms. In addition, we propose an accelerated version, the Bregman Proximal DC Algorithm with extrapolation (BPDCAe), with a new restart scheme. We show the global convergence of the iterates generated by BPDCA(e) to a limiting critical point under the assumption of the Kurdyka-Łojasiewicz property or subanalyticity of the objective function and other weaker conditions than those of the existing methods. We applied our algorithms to phase retrieval, which can be described both as a nonconvex optimization problem and as a DC optimization problem. Numerical experiments showed that BPDCAe outperformed existing Bregman proximal-type algorithms because the DC formulation allows for larger admissible step sizes.

This study reports on the electrochemical analysis of coffee extractions at different roasting levels by using a carbon nanotube (CNT) electrode. The roasting levels, ranging from 1 (low) to 6 (high), were determined according to the roasting time after fixing the roasting temperature. Level 1 roasting resulted in light roasted beans and level 6 in dark roasted ones. Based on the roasting level, the concentration of chlorogenic acids, including 3-caffeoylquinic (3CQ), 4-caffeoylquinic (4CQ), and 5-caffeoylquinic (5CQ) acid, can be determined. Cyclic voltammetry (CV) experiments revealed that the reduction current at +0.27 V was proportional to the concentration of chlorogenic acids. High-performance liquid chromatography (HPLC) revealed an inverse correlation between the roasting level and chlorogenic acid amount. The total amounts of chlorogenic acids in coffee extractions determined by HPLC were in agreement with those obtained by CV using the CNT electrode at roasting levels 1 - 5. At level 6, the amount of chlorogenic acids determined by the current peak was larger than that detected by HPLC. As a result, the chlorogenic acid amount was overestimated in the CV experiment at +0.27 V, indicating that electrochemically active materials were generated at level 6. The CV profile showed that the reduction peak at +0.10 V increased with an increase in roasting level. Thus, the peak intensity at +0.10 V can be used to evaluate the roasting level even if the concentration or dilution conditions are provided.

A set of flapping acene dimers fused with an 8π cyclooctatetraene (COT) ring showed distinct excited-state dynamics in solution. While the anthracene dimer showed a fast V-shaped-to-planar conformational change within 10 ps in the lowest excited singlet state, reminding us of extended Baird aromaticity, the tetracene dimer and the pentacene dimer underwent intramolecular singlet fission (SF) in different manners: A fast and reversible SF with a characteristic delayed fluorescence (FL), and a fast and quantitative SF, respectively. Conformational flexibility of the fused COT linkage plays an important role in these ultrafast dynamics, demonstrating the utility of the flapping molecular series as a versatile platform for designing photofunctional systems.

Surimi gelation at < 40 °C is termed “suwari”. Unintentional suwari during the blending and shaping processes (before heating) in the manufacturing of surimi gel products causes serious challenges, because of imperfect molding and clogging in machines.To solve them, effects of transglutaminase and protease inhibitors on suwari gelation properties of Alaska pollock surimi were investigated at 25 °C. Furthermore, thermal gelation properties of surimi after the suwari suppression were studied for preparing gel products with superior physical properties.A 1.0 g/100 g N-ethylmaleimide (NEM) or ethylene glycol tetraacetic acid (EGTA) significantly suppressed suwari at 25 °C for 24 h. The surimi gel with 1.0 g/100 g NEM exhibited superior breaking properties, whereas those of the gel with 1.0 g/100 g EGTA deteriorated upon suwari suppression followed by heating at 90 °C. Adding 10 μmol/L cysteine protease inhibitors, such as NEM or E−64, suppressed the peptide generation in surimi at 25 °C (1.7–2.5 μg/mL) compared to that in the control sample (12.2 μg/mL). Therefore, the inhibition of both transglutaminase and cysteine protease activities was essential for prolonged suppression of the suwari phenomenon and obtaining the heat-induced surimi gel with superior physical properties after the long-term suwari suppression., 公開日: 2022-06-23

The structural protein Core of hepatitis C virus (HCV), a cytosolic protein, induces endoplasmic reticulum (ER) stress and unfolded protein response (UPR) in hepatocytes, and is responsible for the pathogenesis of persistent HCV infection. Using yeast as a model system, we evaluated mechanisms underlying Core-induced interference of ER homeostasis and UPR, and found that UPR is induced by the immature Core (aa 1-191, Core191) but not by the mature Core (aa 1-177, Core177). Interestingly, Core191 inhibits both ERAD-L, a degradation system responsible for misfolded/unfolded proteins in the ER lumen, and ERAD-M, a degradation system responsible for proteins carrying a misfolded/unfolded region in the ER membrane. In contrast, Core177 inhibits ERAD-M but not ERAD-L. In addition, requirement of an unfolded protein sensor in the ER lumen suggested that inhibition of ERAD-L is probably responsible for Core191-dependent UPR activation. These results implicate inadequate maturation of Core as a trigger for induction of ER stress and UPR.

The excited-state dynamics of molecular aggregates are governed by their potential energy landscape that can hardly be controlled artificially. However, it is possible to alter the excited state dynamics by a strong coupling between light and molecules (polariton formation) because it can decouple the electronic and vibrational degrees of freedom. Here, we demonstrate this polaron decoupling effect on the photochemical dynamics in singlet fission (SF) of amorphous rubrene thin films embedded in optical microcavities. The vibronic feature of polariton states in this system is characterized through the analysis of steady state absorption spectra by using the Holstein-Tavis-Cummings model. On the basis of this analysis, we show with time-resolved spectroscopy that the SF rate following a resonant excitation of the lowest energy polariton state is indeed modulated when the cavity photon energy is changed. A numerical simulation by using Fermi’s golden rule formula with the vibronic polariton feature successfully accounts for the observed modulation of the SF rate, indicating that the polaron decoupling plays a decisive role in the nonadiabatic dynamics.

We present a wearable haptic assistance robotic system for augmented motor learning called Naviarm. This system comprises two robotic arms that are mounted on a user's body and are used to transfer one person's motion to another offline. Naviarm pre-records the arm motion trajectories of an expert via the mounted robotic arms and then plays back these recorded trajectories to share the expert's body motion with a beginner. The Naviarm system is an ungrounded system and provides mobility for the user to conduct a variety of motions. In this paper, we focus on the temporal aspect of motor skill and use a mime performance as a case study learning task. We verified the system effectiveness for motor learning using the conducted experiments. The results suggest that the proposed system has benefits for learning sequential skills.

We present a wearable haptic assistance robotic system for augmented motor learning called Naviarm. This system comprises two robotic arms that are mounted on a user's body and are used to transfer one person's motion to another offline. Naviarm prerecords the arm motion trajectories of an expert via the mounted robotic arms and then plays back these recorded trajectories to share the expert's body motion with a beginner. The Naviarm system is an ungrounded system and provides mobility for the user to conduct a variety of motions. In our demonstration, the user will experience the recording of arm movement with backpack-type robotic arm. Then, the recorded movement will replayed and the user can experience the haptic feedback.

An electrochemical analysis of polyphenols (theaflavin (TF1), theaflavin-3-gallate (TF2A), theaflavin-3'-gallate (TF2B), theaflavin-3,3'-digallate (TF3), and epigallocatechingallate (EGCG)) in a black tea infusion is demonstrated. The characterization of each polyphenol in a solution containing only a single type of polyphenol for a redox reaction at the CNT electrode with cyclic voltammetry (CV) was conducted. The oxidation peak at around +0.30 V for TF1 is assigned to catechol group in a benzotropolone ring. The oxidation peak at around +0.35 V for TF2A, TF2B, and TF3 is assigned to both of the catechol groups in the benzotropolone ring and the pyrogallol group in the gallate ring. The oxidation peak at around +0.35 V for EGCG is assigned to a pyrogallol group in the gallate ring. Current changes of those individual polyphenols at the peak potential are proportional to their concentrations (linear range 0.28 - 94 μM; detection limit 0.11 μM). The CV curve for real black tea, which is mainly composed of a mixture of the mentioned five compounds, is produced by the sum of those. The current change of the mixture solution of polyphenols is also proportional to the mass concentration of the total polyphenols and the sensitivity defined as the slope of current vs. concentration plot is independent of the ratio of the individual polyphenols. This indicates that the peak current at around +0.35 V can quantify the total amount of polyphenols in a black tea. Additionally, the shape of the CV curve can roughly estimate the ratio of [catechins]/[theaflavins]. The values for real samples determined from CVs show good agreement with that obtained by high-performance liquid chromatography.

A number of studies have shown the bifidogenic effects of either probiotic bifidobacteria or inulin, and this bifidogenic shift in the composition of the colonic microbiota is likely the basis for their positive impact on human health. This study aimed to evaluate the effects of synbiotics containing the probiotic bacterium Bifidobacterium animalis subsp. lactis (B. lactis) GCL2505 and inulin on the levels of intestinal bifidobacteria compared with B. lactis GCL2505 alone. A randomized, double‐blind, placebo‐controlled, crossover trial was carried out involving 60 healthy subjects with a tendency for constipation using fermented milk containing B. lactis GCL2505 and inulin (synbiotic), only B. lactis GCL2505 (probiotic), and placebo. Fecal samples were collected at the end of each 2‐week intervention period, and the bifidobacterial count was analyzed by quantitative real‐time PCR. The numbers of total bifidobacteria and B. lactis in feces were significantly increased during the probiotic and synbiotic intake periods compared with the placebo intake period. Furthermore, the numbers of total bifidobacteria and endogenous bifidobacteria were significantly higher in the synbiotic intake period compared with the probiotic intake period, while there was no difference in the number of B. lactis. These results suggested that the synbiotics containing B. lactis GCL2505 and inulin had a greater effect on the number of bifidobacteria than a drink containing probiotics alone and could be useful for the improvement of the intestinal environment.

Electrocatalytic performance of metal nanoparticles (NPs) has been studied to apply for electrochemical devices such as fuel cells and electrochemical sensors. We have developed metal NPs embedded carbon film electrodes by co-sputtering of metal and carbon [1]. Various kinds of metals including Pt, Pd, Au, Ni, Cu and their alloys can be fabricated in the carbon film by using unbalanced magnetron (UBM) sputtering and applied for detecting hydrogen peroxide, glucose [1], heavy metals [2,3] and sugar markers [4, 5]. The electrocatalytic activity of metal NPs can be modulated by changing electronegativity of substrate such as carbon electrodes. Here, we proposed Ni NPs electrodeposited on nitrogen containing carbon film electrodes. Method The carbon films were prepared by unbalanced magnetron sputtering equipment and then treated by N2 plasma. The surface of the films were characterized by XPS. Then NiNP was electrodeposited onto both plasma treated and untreated carbon films by changing the deposition potentials. The fabricated electrodes were potential cycled to sufficiently form surface Ni(OH)2 on the surface of NiNPs, then applied for measuring sugar oxidation such as glucose and oligosaccharide in alkaline solutions with different pH. Results and Discussion The nitrogen containing carbon film electrode show unique electrochemical performances including reduction of overpotentials for oxygen reduction and oxidation of some biochemicals such as NADH and L-ascorbic acid [6]. The films also show excellent biocompatibility to suppress the fouling of proteins during electrochemical measurements [7]. When we deposited NiNPs onto the nitrogen containing carbon film, the size of NiNPs became smaller by decreasing potential from -1000 to -1300 mV. Since the size of NiNPs at N2 plasma treated surface is larger than that at pure carbon film, we adjusted the potential to obtain similar NiNPs size on both N2 plasma treated and untreated carbon surfaces. After deposition, both electrodes were potential cycled between 0 and 0.70 V (vs Ag/AgCl) to form surface Ni(OH)2 , which is confirmed by HR-TEM, and HAADF-STEM-EDS images. The redox reaction peaks of Ni(OH)2 oxidation and NiOOH reduction is almost identical when the scan rate is slow (1 mV/s). However, the oxidation and reduction peaks shifted positive and negative directions, respectively at Ni(OH)2 modified untreated carbon film with increasing potential scan rate up to 100 mV/s. In contrast, peak separation increase at Ni(OH)2 modified N2 plasma treated carbon film is greatly suppressed suggesting fast redox reaction similar to at Ni(OH)2. We applied both NiNPs deposited plasma treated and untreated carbon film electrodes for electrocatalytic oxidation of glucose and maltopentaose (G5) in alkaline media. Higher electrocatalytic oxidation currents of glucose was observed at NiNPs on nitrogen containing carbon film compared with those at NiNPs on untreated carbon film particularly in higher glucose concentration region (> 1mM). Moreover, the electrocatalytic current was started to increase sharply at +0.28 V at the Ni@Ni(OH)2-NP/N-C, while that at Ni@Ni(OH)2-NP/C was started to increased gradually at +0.34 V. These results could be due to the slightly formed NiOOH at the low potential region which cannot be detected as current change.And 60 mV potential difference could be interpreted as electrostatic interaction between G5 and electrode surface. In conclusion, the electrocatalytic activity of NiNPs can be enhanced by modifying NiNPs on the N2 plasma treated carbon films, which shows enhanced current and lower onset potential for electrocatalytically oxidation of G5. References [1] T. You, O. Niwa, M. Tomita, S. Hirono,” Characterization of platinum nanoparticle- embedded carbon film electrode and its detection of hydrogen peroxide”, Anal. Chem .,75 (2003) 2080. [2] D. Kato, T. Kamata, D. Kato, H. Yanagisawa, O. Niwa, “Au nanoparticle-embeded carbon films for electrochemical As3+ detection with high sensitivity and stability”, Anal. Chem ., 88 (2016) 2944. [3] S. Shiba, S. Takahashi, T. Kamata, H. Hachiya, D. Kato, O. Niwa, “Selective Au Electrodeposition on Au Nanoparticles Embedded in Carbon Film Electrode for Se(IV) Detection” Sensors and Materials ., 31 (2019) 1135. [4] S. Shiba, D. Kato, T. Kamata, O. Niwa,” Co-sputter deposited Nickel-Copper bimetallic nanoalloy embedded carbon films for electrocatalytic biomarker detection”, Nanoscale , 8 (2016) 12887. [5] S. Shiba, R. Maruyama, T. Kamata, D. Kato, O. Niwa, “Chromatographic determination of sugar probes used for gastrointestinal permeability test by employing nickel-copper nanoalloy embedded in carbon film electrodes”, Electroanalysis , 30 (2018) 1407. [6] T. Kamata, D. Kato, O. Niwa,”Electrochemical performance at sputter-deposited nanocarbon film with different surface nitrogencontaining groups”, Nanoscale, 11 (2019) 10239. [7] S. Ohta, S.Shiba, T. Yajima, T. Kamata, D. Kata, O. Niwa, “Gas-phase Treatment Methods for Chemical Termination of Sputtered Nanocarbon Film Electrodes to Suppress Surface Fouling by Proteins”, J. Photopolym. Sci. Tech., 32 (2019) 523

Bifidobacterium animalis ssp. lactis GCL2505 (B. lactis GCL2505) is able to survive passage through the intestine and then proliferate, leading to an increase in the amount of gut bifidobacteria. In the present study, we evaluated the impact of B. lactis GCL2505 on abdominal visceral fat storage in overweight and mildly obese Japanese adults. This clinical study was a double-blind, randomized, placebo-controlled, parallel-group comparative trial performed for 12 weeks. Healthy Japanese subjects (N=137) with body mass indices ranging from 23 to 30 kg/m2 consumed either fermented milk containing B. lactis GCL2505 or a placebo every day, and then visceral and subcutaneous abdominal fat areas were measured by computed tomography as the primary endpoints. The number of fecal bifidobacteria was also measured. Visceral fat area, but not subcutaneous fat area, was significantly reduced from baseline at 8 and 12 weeks in the GCL2505 group, compared with the placebo group. The total number of fecal bifidobacteria was significantly increased in the GCL2505 group. These results indicate that B. lactis GCL2505 reduces abdominal visceral fat, a key factor associated with metabolic disorders. This finding suggests that this probiotic strain can potentially serve as a specific functional food to achieve visceral fat reduction in overweight or mildly obese individuals.

In this study, the electrochemical-chemical-electrochemical (ECE) mechanism of monohydroxycinnamic (ferulic, sinapic, and p-coumaric) acid oxidation is presented from a new perspective. Successful mechanistic interpretation employs a carbon nanotube (CNT)-carboxymethylcellulose (CMC) electrode, which exhibits distinctive ECE behavior in cyclic voltammetry (CV), unlike other electrodes. The proposed mechanism is confirmed by simulations using DigiElch software. Monohydroxycinnamic acids are oxidized by an EECE mechanism (ErErCiEr = A ⇄ B + e−; B ⇄ C + e−; C ⇄ D; D + 2e− ⇄ E). The first electrochemical step (ErEr) comprises two consecutive oxidations (A ⇄ B + e−; B ⇄ C + e−), which appear as separate anodic peaks. The reaction at the less positive potential involves oxidation of the hydroxyl group to a phenoxy radical (B), which exists in three mesomeric forms that are oxidized in the second reaction to cations (C) that undergo hydrolysis to their respective o-quinones (D). The hydrolysis reaction (C → D) exhibits a large rate constant and occurs rapidly on the voltammetric time scale. Thus, the overall ErErCi process appears to be chemically irreversible. Finally, the monohydroxycinnamic acids are converted into dihydroxycinnamic acids (caffeic or 5-hydroxyferulic acids), which condense into a reversible, two-electron catechol/o-quinone redox system (D + 2e− ⇄ E). Electrochemical quantitation is based on the proportionality of the peak currents to the monohydroxycinnamic acid concentration. The voltammetrically determined monohydroxycinnamic acid content in real food samples agrees with the high-performance liquid chromatography results. The CNT-CMC electrode extends fundamental studies of the ECE mechanism to systems that cannot be examined using conventional electrodes, thereby demonstrating its utility in electrochemical studies.

Electrocatalytic performance of metal nanoparticles (NPs) has been studied to apply for electrochemical devices such as fuel cells and electrochemical sensors. We have developed metal NPs embedded carbon film electrodes by co-sputtering of metal and carbon [1]. Various kinds of metals including Pt, Pd, Au, Ni, Cu and their alloys can be fabricated in the carbon film by using unbalanced magnetron (UBM) sputtering and applied for detecting hydrogen peroxide, glucose [1], heavy metals [2,3] and sugar markers [4, 5]. The electrocatalytic activity of metal NPs can be modulated by changing electronegativity of neighbor materials. Here, we proposed two electrode structures to modulate the electrocatalytic activity of metal NPs by forming metal NPs on hybrid carbon film electrodes, The electrodes were then applied applied for detecting small organic molecules such as alcohols and sugars. The first electrode structure is Ni(OH)2 NPs electrodeposited on the surface of nitrogen terminated carbon film electrodes. The carbon film was formed by UBM sputtering and the surface was treated by N2 plasma. After treatment, the NiNPs were electrodeposited by applying negative potential(Fig.1 left figure of Electrode Fabrication). The size of NiNPs became smaller by decreasing potential from -1000 to -1300 mV. By taking account of this property, we adjusted the potential to obtain similar NiNPs size on both N2 plasma treated and untreated carbon surfaces. After deposition, the potentials of both electrodes were cycled between 0 and 0.70 V (vs Ag/AgCl) to form surface Ni(OH)2. The redox reaction peaks of Ni(OH)2 oxidation and NiOOH reduction shifted positive and negative directions, respectively at Ni(OH)2 modified untreated carbon film(Fig.1 centor figure of Electrode Fabrication). with increasing potential scan rate. In contrast , peak separation increase at Ni(OH)2 modified N2 plasma treated carbon film is greatly decreased suggesting fast redox reaction. We applied both electrodes for electrocatalytic oxidation of glucose in alkaline media(Fig.1 left of Applications). The oxidation current of glucose at Ni(OH)2 modified N2 plasma treated carbon film electrode shows much larger current than that at Ni(OH)2 modified N2 untreated carbon film electrode. The current of former electrode continued to slightly increase when the glucose concentration is around 7 mM. In contrast, the current of latter electrode was saturated below 3 mM. The other structure we proposed was fabricated by electroplating the Ni onto PdNPs or AuNPs embedded carbon film electrodes. By using the overpotential difference between PdNPs and carbon surface, we successfully electrodeposited NiNPs selectively only on the embedded PdNPs, resulting Ni-Pd heterodimer structure on the electrode surface(Fig.1 right of Electrode Fabrication). The average size of deposited NiNPs onto PdNPs is smaller than that deposited on the pure carbon film electrode because the embedded PdNPs worked as growth core of NiNPs. We cycled the potential in strong alkaline solution to form Ni(OH)2 on the surface of NiNPs. The oxidation peak potential of Ni(OH)2 /Pd heterodimers, which corresponds to surface NiOOH formation reaction, slightly increases with increasing the scan rates from 1 mV/s to 100 mV/s. In contrast, the oxidation peak potential of Ni(OH)2 NP modified pure carbon film(Fig.1 center figure of Electrode Fabrication) shifted more positively (about 0.2 V) with increasing the scan rate, which suggests that the oxidation and reduction cycle of Ni(OH)2 /Pd heterodimer is much faster than that of Ni(OH)2 NP. Both electrodes were applied to electrochemically oxidize methanol. When the concentration of methanol is below 1M, the sensitivity of Ni(OH)2 NP modified carbon film electrode is relatively higher than that at Ni(OH)2 /Pd heterodimer modified carbon film electrode. However, the curent at Ni(OH)2 /Pd heterodimer modified electrodes was superior to that at Ni(OH)2 NP modified electrode when the methanol concentration was higher than 1 M (Fig.1 right figure of Applications). This could be due to the fast regeneration of catalytic sites (NiOOH) resulting in higher turnover rates for methanol oxidation reaction. The above behavior of Ni(OH)2 /Pd heterodimer modified carbon film electrode could be more suitable for energy device such as fuel cell electrode and Ni(OH)2 modified carbon film electrode is more suitable to detect alcohol sensing electrode. In conclusion, the electrocatalytic activity of NiNPs can be largely modulated by changing substrates, suggesting that the design of electrode surfaces are very important to realize high performance electrodes for chemical sensors. References [1] T. You, O. Niwa, M. Tomita, S. Hirono,” Characterization of platinum nanoparticle- embedded carbon film electrode and its detection of hydrogen peroxide”, Anal. Chem .,75 (2003) 2080. [2] D. Kato, T. Kamata, D. Kato, H. Yanagisawa, O. Niwa, “Au nanoparticle-embeded carbon films for electrochemical As3+ detection with high sensitivity and stability”, Anal. Chem ., 88 (2016) 2944. [3] S. Shiba, S. Takahashi, T. Kamata, H. Hachiya, D. Kato, O. Niwa, “Selective Au Electrodeposition on Au Nanoparticles Embedded in Carbon Film Electrode for Se(IV) Detection” Sensors and Materials ., 31 (2019) 1135. [4] S. Shiba, D. Kato, T. Kamata, O. Niwa,” Co-sputter deposited Nickel-Copper bimetallic nanoalloy embedded carbon films for electrocatalytic biomarker detection”, Nanoscale , 8 (2016) 12887. [5] S. Shiba, R. Maruyama, T. Kamata, D. Kato, O. Niwa, “Chromatographic determination of sugar probes used for gastrointestinal permeability test by employing nickel-copper nanoalloy embedded in carbon film electrodes”, Electroanalysis , 30 (2018) 1407. Figure 1