Entropy of capacities on lattices and set systems

We propose a definition for the entropy of capacities defined on lattices. Classical capacities are monotone set functions and can be seen as a generalization of probability measures. Capacities on lattices address the general case where the family of subsets is not necessarily the Boolean lattice of all subsets. Our definition encompasses the classical definition of Shannon for probability measures, as well as the entropy of Marichal defined for classical capacities. Some properties and examples are given.     

Polymerase chain reaction-denaturing gradient gel electrophoresis analysis of microbial community structure in landfill leachate

The structures of microbial communities in water samples obtained from a landfill site that had been a source of environmental pollution by emitting hydrogen sulfide were elucidated using polymerase chain reaction-denaturing gradient gel electrophoresis. The microbial communities, which consisted of a limited number of major microorganisms, were stable for several months. Microorganisms capable of degrading such chemical compounds as 2-hydroxybenzothiazole and bisphenol A were observed in landfill leachate. Microorganisms responsible for the production of hydrogen sulfide were not the primary microbes detected, even in water samples obtained from the site of gas emission.     

Adaptive splitbelt treadmill walking of a biped robot using nonlinear oscillators with phase resetting

To investigate the adaptability of a biped robot controlled by nonlinear oscillators with phase resetting based on central pattern generators, we examined the walking behavior of a biped robot on a splitbelt treadmill that has two parallel belts controlled independently. In an experiment, we demonstrated the dynamic interactions among the robot mechanical system, the oscillator control system, and the environment. The robot produced stable walking on the splitbelt treadmill at various belt speeds without changing the control strategy and parameters, despite a large discrepancy between the belt speeds. This is due to modulation of the locomotor rhythm and its phase through the phase resetting mechanism, which induces the relative phase between leg movements to shift from antiphase, and causes the duty factors to be autonomously modulated depending on the speed discrepancy between the belts. Such shifts of the relative phase and modulations of the duty factors are observed during human splitbelt treadmill walking. Clarifying the mechanisms producing such adaptive splitbelt treadmill walking will lead to a better understanding of the phase resetting mechanism in the generation of adaptive locomotion in biological systems and consequently to a guiding principle for designing control systems for legged robots.     

α-Sulfonato palmitic acid methyl ester-hexaoxyethylene monododecyl ether mixed surfactant system: Interfacial,thermodynamic, and performance property study

Interfacial, thermodynamic, and performance properties of aqueous binary mixtures of α-sulfonato palmitic acid methyl ester, C₁₄H₂₉CH(SO₃Na)COOCH₃(PES), and hexaoxyethylene monododecyl ether, CH₃(CH₂)₁₁(OCH₂CH₂)₆OH (C₁₂E₆), were investigated with tensiometric, conductometric, fluorimetric, and viscometric techniques. The critical micelle concentration (CMC), maximum surface excess, minimum area per molecule of surfactant at the air/water interface, and the thermodynamics of micellization and adsorption were determined. The CMC was very low for mixed systems, indicating probable use as a detergent with less effect on the environment because of surfactant biodegradability and less amount in the environment. The interaction parameter β^m, computed by using the theory of Rubingh and Maeda, indicated an attractive interaction (synergism) between the surfactant molecules, which was also confirmed by proton nuclear magnetic resonance studies in the mixed micelle. The micellar aggregation number (N _agg), determined by using a steady-state fluorescence quenching method at a total surfactant concentration of about ∼10 mM at 25°C, was almost independent of the surfactant mixture composition. The micropolarity and the binding constant (K _sv) for the C₁₂E₆/PES mixed system were determined by the ratio of the intensities (I ₁/I ₃) of the pyrene fluorescence emission spectrum, and the local microenvironment inside the micelle was found to be polar. The viscosity of the mixed system at all mole fractions suggested that mixed micelles are nonspherical in nature. The cloud point of oxyethylene group-containing surfactants was increased by the addition of PES. Foaming was temperature dependent, and a 1∶1 mixed system showed minimum foaming. All performance properties were composition dependent.     

Immunotherapy with 4-1BBL-Expressing iPS Cell‐Derived Myeloid Lines Amplifies Antigen-Specific T Cell Infiltration in Advanced Melanoma

We have established an immune cell therapy with immortalized induced pluripotent stem-cell–derived myeloid lines (iPS-ML). The benefits of using iPS-ML are the infinite proliferative capacity and ease of genetic modification. In this study, we introduced 4-1BBL gene to iPS-ML (iPS-ML-41BBL). The analysis of the cell-surface molecules showed that the expression of CD86 was upregulated in iPS-ML-41BBL more than that in control iPS-ML. Cytokine array analysis was performed using supernatants of the spleen cells that were cocultured with iPS-ML or iPS-ML-41BBL. Multiple cytokines that are beneficial to cancer immunotherapy were upregulated. Peritoneal injections of iPS-ML-41BBL inhibited tumor growth of peritoneally disseminated mouse melanoma and prolonged survival of mice compared to that of iPS-ML. Furthermore, the numbers of antigen-specific CD8⁺ T cells were significantly increased in the spleen and tumor tissues treated with epitope peptide-pulsed iPS-ML-41BBL compared to those treated with control iPS-ML. The number of CXCR6-positive T cells were increased in the tumor tissues after treatment with iPS-ML-41BBL compared to that with control iPS-ML. These results suggest that iPS-ML-41BBL could activate antigen-specific T cells and promote their infiltration into the tumor tissues. Thus, iPS-ML-41BBL may be a candidate for future immune cell therapy aiming to change immunological “cold tumor” to “hot tumor”.     

Synthesis and Properties of Dielectric Ceramics from Metallo-Organic Precursors through the Solid-State Reaction of Mixed Gels

A perovskite structure of 0.4Pb(Mg_1/3Nb_2/3)O₃·0.3Pb(Mg_1/2W_1/2)O₃·0.3PbTiO₃ was prepared from metallo-organic precursors through the solid-state reaction of the mixed gels. Three types of mixed gels were crystallized to obtain PbTiO₃, MgNb₂O₆, and MgWO₄ powders. These powders were calcined at 900°C after mixing with a stoichiometric amount of Pb(CH₃COO)₂·3H₂O. The dielectric constant of the ceramic fired at 900°C was improved by adding an excess of 10 mol% Mg(OC₂H₅)₂, and the ceramic achieved X7T specification of the Electric Industries Association standard. The dielectric loss was reduced by adding an excess of 5 mol% Pb(CH₃COO)₂·3H₂O.     

Total Syntheses and Chemical Biology Studies of Hymeglusin and Fusarilactone A,Novel Circumventors of β-Lactam Drug Resistance in Methicillin-Resistant Staphylococcus aureus

Hymeglusin, a previously known eukaryotic hydroxymethylglutaryl-CoA (HMG−CoA) synthase inhibitor, was identified as circumventing the β-lactam drug resistance in methicillin-resistant Staphylococcus aureus (MRSA). We describe the concise total syntheses of a series of natural products, which enabled determination of the absolute configuration of fusarilactone A and provided structure-activity relationship information. Based on previous reports, we speculated that the target protein of this circumventing effect may be MRSA bacterial HMG−CoA synthase (mvaS). We found that this enzyme was dose-dependently inhibited by hymeglusin. Furthermore, overexpression of the MRSA mvaS gene and site-directed mutagenesis studies suggested its binding site and the mechanism of action.