554 research outputs found
Study on serum fluorescence spectra based on wavelet transform
Blood plays an important role in clinical diagnosis and treatment and as such, the analysis of blood spectrum will be of very important practical significance. Serum fluorescence emission intensity is closely related with the excitation wavelength; when the excitation wavelength is 230 nm, the blood lipid concentration and fluorescence intensity was significantly correlated. On the contrary, blood sugar was almost with no effect on the strength. Wavelet analysis was used in signal de-noising to get a wide range of applications. In this paper, fluorescence spectrum was divided into four layers by db4 wavelet, according to the principle of stein unbiased likelihood estimate.To choose the threshold, noise was removed and reconstruction signal received. This paper studied the correlation between blood lipid concentration and original fluorescence intensity, reconstruction fluorescence intensity and the fourth layer fluorescence strength. Some significant results were achieved, providing an experimental basis for further study on the fluorescence spectrum of blood
Active pixel sensor having intra-pixel charge transfer with analog-to-digital converter
An imaging device formed as a monolithic complementary metal oxide semiconductor Integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node and an analog-to-digital converter formed in the substrate connected to the output of the readout circuit
Active pixel sensor having intra-pixel charge transfer with analog-to-digital converter
An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node and an analog-to-digital converter formed in the substrate connected to the output of the readout circuit
Electromagnetic Momentum in Dispersive Dielectric Media
When the effects of dispersion are included, neither the Abraham nor the
Minkowski expression for electromagnetic momentum in a dielectric medium gives
the correct recoil momentum for absorbers or emitters of radiation. The total
momentum density associated with a field in a dielectric medium has three
contributions: (i) the Abraham momentum density of the field, (ii) the momentum
density associated with the Abraham force, and (iii) a momentum density arising
from the dispersive part of the response of the medium to the field, the latter
having a form evidently first derived by D.F. Nelson [Phys. Rev. A 44, 3985
(1991)]. All three contributions are required for momentum conservation in the
recoil of an absorber or emitter in a dielectric medium. We consider the
momentum exchanged and the force on a polarizable particle (e.g., an atom or a
small dielectric sphere) in a host dielectric when a pulse of light is incident
upon it, including the dispersion of the dielectric medium as well as a
dispersive component in the response of the particle to the field. The force
can be greatly increased in slow-light dielectric media.Comment: 9 pages. To be published by Optics Communication
Dynamin2- and endothelial nitric oxide synthaseâregulated invasion of bladder epithelial cells by uropathogenic Escherichia coli
eNOS-mediated S-nitrosylation of dynamin2 promotes infection of epithelial cells by E. coli
Negative moments of characteristic polynomials of random GOE matrices and singularity-dominated strong fluctuations
We calculate the negative integer moments of the (regularized) characteristic
polynomials of N x N random matrices taken from the Gaussian Orthogonal
Ensemble (GOE) in the limit as . The results agree nontrivially
with a recent conjecture of Berry & Keating motivated by techniques developed
in the theory of singularity-dominated strong fluctuations. This is the first
example where nontrivial predictions obtained using these techniques have been
proved.Comment: 13 page
Recent contrasting winter temperature changes over North America linked to enhanced positive PacificâNorth American pattern
Recently enhanced contrasts in winter (DecemberâJanuaryâFebruary) mean temperatures and extremes (cold southeast and warm northwest) across North America have triggered intensive discussion both within and outside of the scientific community, but the mechanisms responsible for these contrasts remain unresolved. Here we use a combination of observations and reanalysis data sets to show that the strengthened contrasts in winter mean temperatures and extremes across North America are closely related to an enhancement of the positive PacificâNorth American (PNA) pattern during the second half of the 20th century. Recent intensification of positive PNA events is associated with amplified planetary waves over North America, driving coldâair outbreaks into the southeast and warm tropical/subtropical air into the northwest. This not only results in a strengthened winter mean temperature contrast but increases the occurrence of the oppositeâsigned extremes in these two regions.Key PointsThe enhanced contrasts in winter mean temperatures and extremes in North America are observedRecent enhancement of positive PNA is a main cause of the contrasting winter temperature changesThe study provides a framework for detection and attribution of climate change in North AmericaPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/115952/1/grl53404_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/115952/2/grl53404.pd
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