6,397 research outputs found
Phase-coexisting patterns, horizontal segregation and controlled convection in vertically vibrated binary granular mixtures
We report new patterns, consisting of coexistence of sub-harmonic/harmonic
and asynchronous states [for example, a granular gas co-existing with (i)
bouncing bed, (ii) undulatory subharmonic waves and (iii) Leidenfrost-like
state], in experiments on vertically vibrated binary granular mixtures in a
Heleshaw-type cell. Most experiments have been carried out with equimolar
binary mixtures of glass and steel balls of same diameter by varying the total
layer-height () for a range of shaking acceleration (). All patterns
as well as the related phase-diagram in the ()-plane have been
reproduced via molecular dynamics simulations of the same system. The
segregation of heavier and lighter particles along the horizontal direction is
shown to be the progenitor of such phase-coexisting patterns as confirmed in
both experiment and simulation. At strong shaking we uncover a {\it partial}
convection state in which a pair of convection rolls is found to coexist with a
Leidenfrost-like state. The crucial role of the relative number density of two
species on controlling the buoyancy-driven granular convection is demonstrated.
A possible model for spontaneous horizontal segregation is suggested based on
anisotropic diffusion
The Rapid and Sensitive Quantitative Determination of Galactose by Combined Enzymatic and Colorimetric Method: Application in Neonatal Screening
The quantitative measurement of galactose in blood is essential for the early diagnosis, treatment, and dietary monitoring of galactosemia patients. In this communication, we aimed to develop a rapid, sensitive, and cost-effective combined method for galactose determination in dry blood spots. This procedure was based on the combination of enzymatic reactions of galactose dehydrogenase (GalDH), dihydrolipoyl dehydrogenase (DLD), and alkaline phosphates with a colorimetric system. The incubation time and the concentration of enzymes used in new method were also optimized. The analytical performance was studied by the precision, recovery, linearity, and sensitivity parameters. Statistical analysis was applied to method comparison experiment. The regression equation and correlation coefficient (R2) were Y = 0.0085x + 0.032 and R2 = 0.998, respectively. This assay exhibited a recovery in the range of 91.7–114.3 % and had the limit detection of 0.5 mg/dl for galactose. The between-run coefficient of variation (CV) was between 2.6 and 11.1 . The within-run CV was between 4.9 and 9.2 . Our results indicated that the new and reference methods were in agreement because no significant biases exist between them. Briefly, a quick and reliable combined enzymatic and colorimetric assay was presented for application in newborn mass screening and monitoring of galactosemia patients. © 2016 Springer Science+Business Media New Yor
Dynamics of parametric fluctuations induced by quasiparticle tunneling in superconducting flux qubits
We present experiments on the dynamics of a two-state parametric fluctuator
in a superconducting flux qubit. In spectroscopic measurements, the fluctuator
manifests itself as a doublet line. When the qubit is excited in resonance with
one of the two doublet lines, the correlation of readout results exhibits an
exponential time decay which provides a measure of the fluctuator transition
rate. The rate increases with temperature in the interval 40 to 158 mK. Based
on the magnitude of the transition rate and the doublet line splitting we
conclude that the fluctuation is induced by quasiparticle tunneling. These
results demonstrate the importance of considering quasiparticles as a source of
decoherence in flux qubits.Comment: 12 pages, including supplementary informatio
Comparison of technetium-99m IgG with technetium-99m red blood cells labeling in cardiac blood-pool scintigraphy: A preliminary study
This first clinical prospective study was conducted to use of technetium-99m immunoglobulin G (99mTc-IgG) as compared with autologous 99mTc-red blood cells (RBC) in gated blood pool ventriculography. We studied 12 patients who referred to us for a possible diagnosis of liver hemangioma or infection. Six patients underwent gated planar blood pool (GPBP) acquisition using 99mTc-RBC and 6 GPBP acquisition using 99mTc-IgG. The use of 99mTc-IgG in cardiac blood pool studies provided comparable images to 99mTc-RBC. In conclusion, 99mTc-IgG, which is readily available and needs only a single injection, may be an attractive alternative to 99mTc-RBC for the estimation of various cardiac function parameters like left ventricular function
The menopausal age and associated factors in Gorgan, Iran
Background: Considering the physical, emotional and psychological complications of early or delayed menopause on women's life, it is necessary to determine associated factors of menopause age. This study designed to determine menopausal age and associated factors in women of Gorgan, i.e. the capital of Golestan province in the north-east of Iran. Methods: In this cross-sectional study, 804 menopausal women in Gorgan were selected via two-stage sampling method in 2009. The study included only women who had undergone natural menopause and had their last menstrual bleeding at least one year before. Data were gathered through structured questionnaire that included individual characteristics, socioeconomic characteristics, menstrual and fertility characteristics and climacteric complaints. Socioeconomic status was defined using principal component analysis. Data were analyzed with Tstudent's and ANOVA tests using SPSS version 16 (SPSS Inc, Chicago, IL, USA) for Windows. Results: The mean menopause age was 47.6±4.45 years with the median age of 48 years. The mean menopause age in women with first pregnancy before 30 years (47.58±4.47years), without pregnancy (46.26±4.90years) and without delivery (46.30±4.47years) was significantly lower than others (p 0.05). Socioeconomic status was not associated significantly with menopause age (p>0.05). Conclusion: This study illustrated that menstrual and fertility factors have influence on menopausal age while socioeconomic factors were not effective
Improved Detection Rates for Close Binaries Via Astrometric Observations of Gravitational Microlensing Events
In addition to constructing a Galactic matter mass function free from the
bias induced by the hydrogen-burning limit, gravitational microlensing allows
one to construct a mass function which is less affected by the problem of
unresolved binaries (Gaudi & Gould). However, even with the method of
microlensing, the photometric detection of binaries is limited to binary
systems with relatively large separations of of their combined
Einstein ring radius, and thus the mass function is still not totally free from
the problem of unresolved binaries. In this paper, we show that by detecting
distortions of the astrometric ellipse of a microlensing event with high
precision instruments such as the {\it Space Interferometry Mission}, one can
detect close binaries at a much higher rate than by the photometric method. We
find that by astrometrically observing microlensing events, of
binaries with separations of can be detected with the detection
threshold of 3%. The proposed astrometric method is especially efficient at
detecting very close binaries. With a detection threshold of 3% and a rate of
10%, one can astrometrically detect binaries with separations down to .Comment: total 14 pages, including 5 Figures and no Table (For figure 1,
please send a request mail to [email protected]), accepted to
ApJ (Vol 525, 000), updated versio
Dvali-Gabadadze-Porrati Cosmology in Bianchi I brane
The dynamics of Dvali-Gabadadze-Porrati Cosmology (DGP) braneworld with an
anisotropic brane is studied. The Friedmann equations and their solutions are
obtained for two branches of anisotropic DGP model. The late time behavior in
DGP cosmology is examined in the presence of anisotropy which shows that
universe enters a self-accelerating phase much later compared to the isotropic
case. The acceleration conditions and slow-roll conditions for inflation are
obtained
ZZ freedom in two qubit gates
Superconducting qubits on a circuit exhibit an always-on state-dependent
phase error. This error is due to sub-MHz parasitic interaction that repels
computational levels from non-computational ones. We study a general theory to
evaluate the `static' repulsion between seemingly idle qubits as well as the
`dynamical' repulsion between entangled qubits under microwave driving gate. By
combining qubits of either the same or opposite anharmonicity signs we find the
characteristics of static and dynamical ZZ freedoms. The latter universally
eliminate the parasitic repulsion, leading us to mitigate high fidelity gate
operation. Our theory introduces new opportunities for making perfect entangled
and unentangled states which is extremely useful for quantum technology.Comment: 13 page
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