4,463 research outputs found
Purification and Characterization of Recombinant Darbepoetin Alfa from Leishmania tarentolae
Darbepoetin alfa is a biopharmaceutical glycoprotein that stimulates erythropoiesis and is used to treat anemia, which associated with renal failure and cancer chemotherapy. We herein describe the structural characterization of recombinant darbepoetin alfa produced by Leishmania tarentolae T7-TR host. The DNA expression cassette was integrated into the L. tarentolae genome through homologous recombination. Transformed clones were selected by antibiotic resistance, diagnostic PCRs, and protein expression analysis. The structure of recombinant darbepoetin alfa was analyzed by isoelectric focusing, ultraviolet–visible spectrum, and circular dichroism (CD) spectroscopy. Expression analysis showed the presence of a protein band at 40 kDa, and its expression level was 51.2 mg/ml of culture medium. Darbepoetin alfa have 5 isoforms with varying degree of sialylation. The UV absorption and CD spectra were analogous to original drug (Aranesp), which confirmed that the produced protein was darbepoetin alfa. Potency test results revealed that the purified protein was biologically active. In brief, the structural and biological characteristics of expressed darbepoetin alfa were very similar to Aranesp which has been normally expressed in CHO. Our data also suggest that produced protein has potential to be developed for clinical use. © 2016, Springer Science+Business Media New York
Detection of microcalcifications in mammograms using higher order statistics
Cataloged from PDF version of article.A new method for detecting microcalcifications in
mammograms is described. In this method, the mammogram image
is first processed by a subband decomposition filterbank. The
bandpass subimage is divided into overlapping square regions
in which skewness and kurtosis as measures of the asymmetry
and impulsiveness of the distribution are estimated. The detection
method utilizes these two parameters. A region with high
positive skewness and kurtosis is marked as a region of interest.
Simulation results show that this method is successful in detecting
regions with microcalcifications
Full counting statistics of information content
We review connections between the cumulant generating function of full
counting statistics of particle number and the R\'enyi entanglement entropy. We
calculate these quantities based on the fermionic and bosonic path-integral
defined on multiple Keldysh contours. We relate the R\'enyi entropy with the
information generating function, from which the probability distribution
function of self-information is obtained in the nonequilibrium steady state. By
exploiting the distribution, we analyze the information content carried by a
single bosonic particle through a narrow-band quantum communication channel.
The ratio of the self-information content to the number of bosons fluctuates.
For a small boson occupation number, the average and the fluctuation of the
ratio are enhanced.Comment: 16 pages, 5 figure
Microlensing toward crowded fields: Theory and applications to M31
We present a comprehensive treatment of the pixel-lensing theory and apply it
to lensing experiments and their results toward M31. Using distribution
functions for the distances, velocities, masses, and luminosities of stars, we
derive lensing event rates as a function of the event observables. In contrast
to the microlensing regime, in the pixel-lensing regime (crowded or unresolved
sources) the observables are the maximum excess flux of the source above a
background and the full width at half-maximum (FWHM) time of the event. To
calculate lensing event distribution functions depending on these observables
for the specific case of M31, we use data from the literature to construct a
model of M31, reproducing consistently photometry, kinematics and stellar
population. We predict the halo- and self-lensing event rates for bulge and
disk stars in M31 and treat events with and without finite source signatures
separately. We use the M31 photon noise profile and obtain the event rates as a
function of position, field of view, and S/N threshold at maximum
magnification. We calculate the expected rates for WeCAPP and for a potential
Advanced Camera for Surveys (ACS) lensing campaign. The detection of two events
with a peak signal-to-noise ratio larger than 10 and a timescale larger than 1
day in the WeCAPP 2000/2001 data is in good agreement with our theoretical
calculations. We investigate the luminosity function of lensed stars for noise
characteristics of WeCAPP and ACS. For the pixel-lensing regime, we derive the
probability distribution for the lens masses in M31 as a function of the FWHM
timescale, flux excess and color, including the errors of these observables.Comment: 45 pages, 27 figures LaTeX; corrected typos; published in the
Astrophysical Journal Supplemen
Expected Future Precipitation in Central Iraq Using LARS-WG Stochastic Weather Generator
The Middle East (ME) is characterized by its water shortage problem. This region with its arid climate is expected to be the most vulnerable in the world to the potential impacts of climate change. Iraq (located in ME) is seriously experiencing water shortage problem. To overcome this problem rain water harvesting can be used. In this study the applicability of the long-term weather generator model in downscaling daily precipitation Central Iraq is used to project future changes of precipitation based on scenario of seven General Circulation Models (GCMs) outputs for the periods of 2011-2030, 2046-2065, and 2080-2099. The results indicated that December-February and September-November periods, based on the ensemble mean of seven GCMs, showed an increasing trend in the periods considered; however, a decreasing trend can be found in March, April, and May in the future
CLIMATE CHANGE AND FUTURE PRECIPITATION IN AN ARID ENVIRONMENT OF THE MIDDLE EAST: CASE STUDY OF IRAQ
In this paper impact of climate change on precipitation in the arid environment of Iraq is examined. LARS-WG weather generator was applied to 5 representative regions to model current and future precipitation under climate change. Seven Global Climate Models (GCMs) have been employed to account for any uncertainty on future projection for three selected periods, 2011-2030, 2046-2065 and 2080-2099. Performance of LARS-WG in each site was first evaluated using the Kolmogorov-Smirnov statistical test for fitting wet/dry days in each site, as well as comparison of the mean and standard deviation between the observed and simulated precipitation. The developed LARS-WG models were found to perform well and skilful in simulating precipitation in the arid regions of Iraq as evidenced by the tests carried and the comparison made. The precipitation models were then used to obtain future projections for precipitation using the IPCC scenario SRES A2. Future precipitation results show that most of the Iraq regions are projected to suffer a reduction in annual mean precipitation, especially by the end of the 21st century, while on a seasonal basis most of the regions are anticipated to be wetter in autumn and winter. Journa
AgapeZ1: a Large Amplification Microlensing Event or an Odd Variable Star Towards the Inner Bulge of M31
AgapeZ1 is the brightest and the shortest duration microlensing candidate
event found in the Agape data. It occured only 42" from the center of M31. Our
photometry shows that the half intensity duration of the event6 is 4.8 days and
at maximum brightness we measure a stellar magnitude of R=18.0 with B-R=0.80
mag color. A search on HST archives produced a single resolved star within the
projected event position error box. Its magnitude is R=22.Comment: 4 pages with 5 figure
AGAPE, an experiment to detect MACHO's in the direction of the Andromeda galaxy
The status of the Agape experiment to detect Machos in the direction of the
andromeda galaxy is presented.Comment: 4 pages, 1 figure in a separate compressed, tarred, uuencoded uufile.
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