Waseda University

About: Waseda University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Large Hadron Collider & Catalysis. The organization has 24220 authors who have published 46859 publications receiving 837855 citations. The organization is also known as: Waseda daigaku & Sōdai.

Enzyme nanoarchitectonics: organization and device application

Abstract: Fabrication of ultrasmall functional machines and their integration within ultrasmall areas or volumes can be useful for creation of novel technologies. The ultimate goal of the development of ultrasmall machines and device systems is to construct functional structures where independent molecules operate as independent device components. To realize exotic functions, use of enzymes in device structures is an attractive solution because enzymes can be regarded as efficient machines possessing high reaction efficiencies and specificities and can operate even under ambient conditions. In this review, recent developments in enzyme immobilization for advanced functions including device applications are summarized from the viewpoint of micro/nano-level structural control, or nanoarchitectonics. Examples are roughly classified as organic soft matter, inorganic soft materials or integrated/organized media. Soft matter such as polymers and their hybrids provide a medium appropriate for entrapment and encapsulation of enzymes. In addition, self-immobilization based on self-assembly and array formation results in enzyme nanoarchitectures with soft functions. For the confinement of enzymes in nanospaces, hard inorganic mesoporous materials containing well-defined channels play an important role. Enzymes that are confined exhibit improved stability and controllable arrangement, which are useful for formation of functional relays and for their integration into artificial devices. Layer-by-layer assemblies as well as organized lipid assemblies such as Langmuir–Blodgett films are some of the best media for architecting controllable enzyme arrangements. The ultrathin forms of these films facilitate their connection with external devices such as electrodes and transistors. Artificial enzymes and enzyme-mimicking catalysts are finally briefly described as examples of enzyme functions involving non-biological materials. These systems may compensate for the drawbacks of natural enzymes, such as their instabilities under harsh conditions. We believe that enzymes and their mimics will be freely coupled, organized and integrated upon demand in near future technologies.

Indications of intermediate-scale anisotropy of cosmic rays with energy greater than 57 EeV in the northern sky measured with the surface detector of the Telescope Array experiment

Abstract: We have searched for intermediate-scale anisotropy in the arrival directions of ultrahigh-energy cosmic rays with energies above 57 EeV in the northern sky using data collected over a 5 yr period by the surface detector of the Telescope Array experiment. We report on a cluster of events that we call the hotspot, found by oversampling using 20° radius circles. The hotspot has a Li-Ma statistical significance of 5.1σ, and is centered at R.A. = 146.°7, decl. = 43.°2. The position of the hotspot is about 19° off of the supergalactic plane. The probability of a cluster of events of 5.1σ significance, appearing by chance in an isotropic cosmic-ray sky, is estimated to be 3.7 × 10-4 (3.4σ). © 2014. The American Astronomical Society. All rights reserved.

Work Engagement in Japan: Validation of the Japanese Version of the Utrecht Work Engagement Scale

Abstract: The purpose of this study was to validate the Japanese version of the Utrecht Work Engagement Scale (UWES-J) Employees from three independent samples completed the questionnaire (total N= 2,334) Confirmatory factor analyses using the multiple-group method revealed that, instead of the original three-factor model, a one-factor model that assumes that all engagement items load on one single factor fitted the data Moreover, the one-factor structure was invariant across all three samples Internal consistency of the scale was sufficiently high (α= 92) and the test–retest reliability with an interval of two months was 66 A series of second-order confirmatory factor analyses to examine construct validity confirmed the hypothesised model, indicating that work engagement was positively related to job satisfaction whereas it was negatively related to strain and burnout However, as in previous studies, professional efficacy, a component of burnout, loaded on the engagement factor These results, in general, suggest the reliability (internal consistency and stability), factorial invariance, and construct validity of the UWES-J in three independent samples Cette etude avait pour objectif de valider la version japonaise de l’Echelle d’Implication au Travail d’Utrecht (UWES-J) 2,334 salaries provenant de trois echantillons independants ont rempli le questionnaire Une analyse factorielle confirmatoire faisant appel a la methode des groupes multiples a montre que le modele originel en trois facteurs devait laisser la place a un modele unifactoriel puisque tous les items d’implication etaient satures sur un unique facteur qui rendait compte a lui seul des donnees En outre, la structure monofactorielle restait identique a elle-meme sur les trois echantillons La consistance interne de l’echelle etait suffisamment elevee (α= 92) et la fidelite test-retest apres une periode de deux mois etait de 66 Une serie d’analyses factorielles confirmatoires de second ordre destinees aetudier la validite de construction ont confirme le modele hypothetique, indiquant que l’implication dans le travail etait en correlation positive avec la satisfaction professionnelle tandis qu’elle etait en relation negative avec la tension nerveuse et le burnout Comme dans des travaux anterieurs, l’efficacite professionnelle, une composante du burnout, etait saturee dans le facteur d’implication Ces resultats, vont dans le sens de la fidelite (consistance interne et stabilite), de la solidite factorielle et de la validite de construction de l’UWES-J dans ces trois echantillons independants

Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT

Abstract: Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.

Fabrication of functional three-dimensional tissues by stacking cell sheets in vitro

Abstract: The fabrication of 3D tissues retaining the original functions of tissues/organs in vitro is crucial for optimal tissue engineering and regenerative medicine. The fabrication of 3D tissues also contributes to the establishment of in vitro tissue/organ models for drug screening. Our laboratory has developed a fabrication system for functional 3D tissues by stacking cell sheets of confluent cultured cells detached from a temperature-responsive culture dish. Here we describe the protocols for the fabrication of 3D tissues by cell sheet engineering. Three-dimensional cardiac tissues fabricated by stacking cardiac cell sheets pulsate spontaneously, synchronously and macroscopically. Via this protocol, it is also possible to fabricate other tissues, such as 3D tissue including capillary-like prevascular networks, from endothelial cells sandwiched between layered cell sheets. Cell sheet stacking technology promises to provide in vitro tissue/organ models and more effective therapies for curing tissue/organ failures.