2,513 research outputs found
Consistent Estimation of Mixed Memberships with Successive Projections
This paper considers the parameter estimation problem in Mixed Membership
Stochastic Block Model (MMSB), which is a quite general instance of random
graph model allowing for overlapping community structure. We present the new
algorithm successive projection overlapping clustering (SPOC) which combines
the ideas of spectral clustering and geometric approach for separable
non-negative matrix factorization. The proposed algorithm is provably
consistent under MMSB with general conditions on the parameters of the model.
SPOC is also shown to perform well experimentally in comparison to other
algorithms
Second-order Nonlinear Optical Microscopy of Spider Silk
Asymmetric -sheet protein structures in spider silk should induce
nonlinear optical interaction such as second harmonic generation (SHG) which is
experimentally observed for a radial line and dragline spider silk by using an
imaging femtosecond laser SHG microscope. By comparing different spider silks,
we found that the SHG signal correlates with the existence of the protein -sheets. Measurements of the polarization dependence of SHG from the
dragline indicated that the -sheet has a nonlinear response
depending on the direction of the incident electric field. We propose a model
of what orientation the -sheet takes in spider silk.Comment: 8 pages, 8 figures, 1 tabl
Sum frequency generation spectroscopy of the attachment disc of a spider
The pyriform silk of the attachment disc of a spider was studied using
infrared-visible vibrational sum frequency generation (SFG) spectroscopy. The
spider can attach dragline and radial lines to many kinds of substrates in
nature (concrete, alloy, metal, glass, plant branches, leaves, etc.) with the
attachment disc. The adhesion can bear the spider's own weight, and resist the
wind on its orb web. From our SFG spectroscopy study, the NH group of arginine
side chain and/or NH group of arginine and glutamine side chain in the
amino acid sequence of the attachment silk proteins are suggested to be
oriented in the disc. It was inferred from the observed doublet SFG peaks at
around 3300 cm that the oriented peptide contains two kinds of
structures.Comment: 21 pages, 8 figure
Metal-nonmetal transition in LixCoO2 thin film and thermopower enhancement at high Li concentration
We investigate the transport properties of LixCoO2 thin films whose
resistivities are nearly an order of magnitude lower than those of the bulk
polycrystals. A metal-nonmetal transition occurs at ~0.8 in a biphasic domain,
and the Seebeck coefficient (S) is drastically increased at ~140 K (= T*) with
increasing the Li concentration to show a peak of magnitude ~120 \muV/K in the
S-T curve of x = 0.87. We show that T* corresponds to a crossover temperature
in the conduction, most likely reflecting the correlation-induced temperature
dependence in the low-energy excitations
Numerical analysis of tsunami-induced inundation behind building along coasts
To evaluate the effects of impermeable rigid buildings located near vertical quay walls on the reduction of the inundation water volumes due to run-up tsunamis, a full-scale three-dimensional numerical analysis is performed using a three-dimensional coupled fluid-structure-sediment interaction model. Numerical results show that the inundation water volume can be reduced with an increase in the shielding ratio of the long-shore width of the buildings with respect to the total width of the coastline, and accordingly the buildings located along the coasts have the reduction effects of the inundation water volume. This suggests that countermeasures against tsunamis can be evaluated in a\ud
comprehensive manner in terms of not only shore protection facilities for tsunamis at relatively high frequencies but also such buildings. Furthermore, the inundation depth at the seaward side of the buildings and the cross-shore bottom flow velocity at the gaps between the buildings increase with the shielding ratio, suggesting an increase in tsunami force and the onset of local scouring when the shielding ratio is large. Consequently, when designing buildings along the coasts, it is essential to consider an appropriate balance between the reduction effects of the inundation water volume and the instability of the buildings caused by the tsunami force and the local scouring
Composition of primary cosmic rays at energies 10(15) to approximately 10(16) eV
The sigma epsilon gamma spectrum in 1 approx. 5 x 1000 TV observed at Mt. Fuji suggests that the flux of primary protons 10 to the 15 approx 10th eV is lower by a factor of 2 approx. 3 than a simple extrapolation from lower energies; the integral proton spectrum tends to be steeper than around to the power V and the spectral index tends to be steeper than Epsilon to the -17th power around 10 to the 14th power eV and the spectral index becomes approx. 2.0 around 10 to the 15th power eV. If the total flux of primary particles has no steepening up to approx 10 to the 15th power eV, than the fraction of primary protons to the total flux should be approx 20% in contrast to approx 45% at lower energies
High energy gamma-rays and hadrons at Mount Fuji
The energy spectra of high energy gamma-rays and hadrons were obtained by the emulsion chamber with 40 c.u. thickness at Mt. Fuji (3750 m). These results are compared with the Monte Carlo calculation based on the same model which is used in a family analysis. Our data are compatible with the model of heavy-enriched primary and scaling in the fragmentation region
Particle interactions at energies over 1000 TeV inferred from gamma-families observed at Mount Fuji
Scaling, mean P sub t, high P sub t jets and others at energies over 1000 TeV are discussed on the basis of gamma-family data with sigma E sub gamma 100 TeV, observed at Mt. Fuji (3750 m). These quantities were examined in connection with the primary composition
Urban Diabetic Women\u27s Perception of Healthy Eating Lifestyles From West Java
This study aimed to explore perceptions about a healthy-eating lifestyle and reasons to practice a healthy-eating lifestyle of women with type 2 diabetes in a city of West Java by using a case study design. Six female patients, with type 2 diabetes, ages 47–63 from a hospital were interviewed guided by the health promotion model. Their healthy-eating lifestyle included currently practicing or not practicing a healthy-eating lifestyle. Reasons to practice were: beliefs for health and for physical energy to work for family, definition of multidimensional health and self-efficacy increased by: support from God, support from family, support from health professionals and improved or deteriorated health status by prior experience. Reasons not to practice were: difficulty in arranging diet, rejecting eating, controlling appetite, and accessing health care services. Related difficulties were interpersonal relations with family and social situation such as social events, expensive medical fee, and distance to the hospital. These findings suggest that women with type 2 diabetes in Indonesia need to be supported with the reasons to practice a healthy-eating lifestyle
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