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.

Low-Dose Aspirin for Primary Prevention of Cardiovascular Events in Japanese Patients 60 Years or Older With Atherosclerotic Risk Factors: A Randomized Clinical Trial

Abstract: the aspirin group and 5 in the no aspirin group. The 5-year cumulative primary outcome event rate was not significantly different between the groups (2.77% [95% CI, 2.40%-3.20%] for aspirin vs 2.96% [95% CI, 2.58%-3.40%] for no aspirin; hazard ratio [HR], 0.94 [95% CI, 0.77-1.15]; P = .54). Aspirin significantly reduced incidence of nonfatal myocardial infarction (0.30 [95% CI, 0.190.47] for aspirin vs 0.58 [95% CI, 0.42-0.81] for no aspirin; HR, 0.53 [95% CI, 0.31-0.91]; P =. 02) and transient ischemic attack (0.26 [95% CI, 0.16-0.42] for aspirin vs 0.49 [95% CI, 0.35-0.69] for no aspirin; HR, 0.57 [95% CI, 0.32-0.99]; P = .04), and significantly increased the risk of extracranial hemorrhage requiring transfusion or hospitalization (0.86 [95% CI, 0.67-1.11] for aspirin vs 0.51 [95% CI, 0.37-0.72] for no aspirin; HR, 1.85 [95% CI, 1.22-2.81]; P = .004). CONCLUSIONS AND RELEVANCE Once-daily, low-dose aspirin did not significantly reduce the risk of the composite outcome of cardiovascular death, nonfatal stroke, and nonfatal myocardial infarction among Japanese patients 60 years or older with atherosclerotic risk factors.

Detection of a Spectral Break in the Extra Hard Component of GRB 090926A

Abstract: We report on the observation of the bright, long gamma-ray burst, GRB 090926A, by the Gamma-ray Burst Monitor and Large Area Telescope (LAT) instruments on board the Fermi Gamma-ray Space Telescope. GRB 090926A shares several features with other bright LAT bursts. In particular, it clearly shows a short spike in the light curve that is present in all detectors that see the burst, and this in turn suggests that there is a common region of emission across the entire Fermi energy range. In addition, while a separate high-energy power-law component has already been observed in other gamma-ray bursts, here we report for the first time the detection with good significance of a high-energy spectral break (or cutoff) in this power-law component around 1.4 GeV in the time-integrated spectrum. If the spectral break is caused by opacity to electron-positron pair production within the source, then this observation allows us to compute the bulk Lorentz factor for the outflow, rather than a lower limit.

Unbinding force of a single motor molecule of muscle measured using optical tweezers

Abstract: The unbinding and rebinding of motor proteins and their substrate filaments are the main components of sliding movement We have measured the unbinding force between an actin filament and a single motor molecule of muscle, myosin, in the absence of ATP, by pulling the filament with optical tweezers The unbinding force could be measured repeatedly on the same molecule, and was independent of the number of measurements and the direction of the imposed loads within a range of +/- 90 degrees The average unbinding force was 92 +/- 44 pN, only a few times larger than the sliding force but an order of magnitude smaller than other intermolecular forces From its kinetics we suggest that unbinding occurs sequentially at the molecular interface, which is an inherent property of motor molecules

Origin of the metallic properties of heavily boron-doped superconducting diamond

Abstract: The recent discovery that heavily boron-doped diamond is a superconductor with a transition temperature of 7.4 K raises the prospect of superconducting devices with the unique properties of diamond. A study of the electronic structure responsible for superconductivity in heavily boron-doped diamond supports the idea that superconductivity is phonon-mediated, and provides information on the electronic structure that must be retained in order to harness this effect in practical devices. The physical properties of lightly doped semiconductors are well described by electronic band-structure calculations and impurity energy levels1. Such properties form the basis of present-day semiconductor technology. If the doping concentration n exceeds a critical value nc, the system passes through an insulator-to-metal transition and exhibits metallic behaviour; this is widely accepted to occur as a consequence of the impurity levels merging to form energy bands2. However, the electronic structure of semiconductors doped beyond nc have not been explored in detail. Therefore, the recent observation of superconductivity emerging near the insulator-to-metal transition3 in heavily boron-doped diamond4,5 has stimulated a discussion on the fundamental origin of the metallic states responsible for the superconductivity. Two approaches have been adopted for describing this metallic state: the introduction of charge carriers into either the impurity bands6 or the intrinsic diamond bands7,8,9. Here we show experimentally that the doping-dependent occupied electronic structures are consistent with the diamond bands, indicating that holes in the diamond bands play an essential part in determining the metallic nature of the heavily boron-doped diamond superconductor. This supports the diamond band approach and related predictions, including the possibility of achieving dopant-induced superconductivity in silicon and germanium7. It should also provide a foundation for the possible development of diamond-based devices10.

Glucose Induced Permeation Control of Insulin through a Complex Membrane Consisting of Immobilized Glucose Oxidase and a Poly(amine)

Abstract: To control the release of insulin in response to the concentration of glucose, a glucose–responsive polymer membrane was designed by combining a glucose oxidase (GOD) immobilized membrane, a sensor for glucose, with a poly(amine) membrane which regulates the permeation rate of insulin. The permeability of insulin was increased by the addition of glucose. Gluconic acid produced by an enzymatic reaction between GOD and glucose induced a decrease in the pH value of the medium. This caused the protonation of tertiary amino groups in the membrane resulting in an increase in the water content of the poly(amine) membrane. The permeability of insulin through a complex membrane thus increases with glucose concentration.