3,051 research outputs found
Automated glycan assembly of arabinomannan oligosaccharides from Mycobacterium tuberculosis
Arabinomannan (AM) polysaccharides are clinical biomarkers for Mycobacterium tuberculosis (MTB) infections due to their roles in the interaction with host cells and interference with macrophage activation. Collections of defined AM oligosaccharides can help to improve the understanding of these polysaccharides and the development of novel therapeutical and diagnostic agents. Automated glycan assembly (AGA) was employed to prepare the core structure of AM from MTB, containing α-(1,6)-Man, α-(1,5)-Ara, and α-(1,2)-Man linkages. The introduction of a capping step after each glycosylation and further optimized reaction conditions allowed for the synthesis of a series of oligosaccharides, ranging from hexa- to branched dodecasaccharides
CCD BVRI and 2MASS Photometry of the Poorly Studied Open Cluster NGC 6631
Here we have obtained the {\it BVRI CCD} photometry down to a limiting
magnitude of 20 for the southern poorly studied open cluster NGC 6631.
It is observed from the {\it 1.88 m} Telescope of Kottamia Observatory in
Egypt. About 3300 stars have been observed in an area of around the cluster center. The main photometric parameters
have been estimated and compared with the results that determined for the
cluster using {\it JHKs 2MASS} photometric database. The cluster's diameter is
estimated to be 10 arcmin; the reddening E(B-V)= 0.68 0.10 mag, E(J-H)=
0.21 0.10 mag, the true modulus (m-M)= 12.16 0.10 mag, which
corresponds to a distance of 2700 125 pc and age of 500 50 Myr.Comment: 13 pages, 6 figure
Electronic Structure of Sr_2FeMoO_6
We have analysed the unusual electronic structure of Sr_2FeMoO_6 combining
ab-initio and model Hamiltonian approaches. Our results indicate that there are
strong enhancements of the intraatomic exchange strength at the Mo site as well
as the antiferromagnetic coupling strength between Fe and Mo sites. We discuss
the possibility of a negative effective Coulomb correlation strength (U_{eff})
at the Mo site due to these renormalised interaction strengths.Comment: To appear in Phys. Rev. Let
A DYNAMIC WATERMARKING MODEL FOR MEDICAL IMAGE AUTHENTICATION
This paper proposes a dynamic watermarking model for the purpose of medical authentication. While transferring the data through a public network there is jittering or tampering of data. This is a matter of concern as any jitter or tampered data is not desirable in the medical field. It is noted that there is loss of life due to corrupted data received leading to wrong diagnosis. The proposed dynamic model proves that the medical image watermarked with the proposed system provides near lossless original image. Since the watermark is generated dynamically it is unique to the images considered therefore enhances the security of the images. The Proposed scheme is in the TIFF (Tagged Image File Format) using RGB colour space. The given watermar
Understanding the bulk electronic structure of Ca1-xSrxVO3
We investigate the electronic structure of Ca1-xSrxVO3 using careful
state-of-the-art experiments and calculations. Photoemission spectra using
synchrotron radiation reveal a hitherto unnoticed polarization dependence of
the photoemission matrix elements for the surface component leading to a
substantial suppression of its intensity. Bulk spectra extracted with the help
of experimentally determined electron escape depth and estimated suppression of
surface contributions resolve outstanding puzzles concerning the electronic
structure in Ca1-xSrxVO3.Comment: 4 pages including 3 figure
Implementation of Fast, Low Power and Area Efficient Carry Select Adder
One of the fastest adders is Carry Select Adder (CSLA) and it perform fast arithmetic functions in many data processing processors. A conventional CSLA has less carry propagation delay (CPD) than ripple carry adder (RCA). A compromise between RCA and carry look ahead adder is provided by Carry select adder. For the CSLA new logic is proposed by reducing redundant logic operations present in conventional CSLA. In the proposed scheme, schedule the carry select (CS) operation before final sum calculation. which is different approach from the conventional. Two carry words ( cin = 0 and 1) bit patterns and fixed cin bits use for generation units and CS logic optimization. Optimized logic units is used to obtain an efficient CSLA design. The proposed work is carried out using Modelsim SE 6.3f and Quatus2 software.
DOI: 10.17762/ijritcc2321-8169.16046
Usability Inspection Report of iLumina
iLumina is a digital library of sharable undergraduate teaching resource materials for science, mathematics, technology, and engineering being developed by the University of North Carolina at Wilmington (UNCW), Collegis, Virginia Tech, Georgia State University, Grand Valley State and
The College of New Jersey. Types of iLumina resources include papers, tutorials, applets,
presentations, visualizations, experiments, assignments, software, exercises
Passive Energy Recapture in Jellyfish Contributes to Propulsive Advantage over other Metazoans
Gelatinous zooplankton populations are well known for their ability to take over perturbed ecosystems. The ability of these animals to outcompete and functionally replace fish that exhibit an effective visual predatory mode is counterintuitive because jellyfish are described as inefficient swimmers that must rely on direct contact with prey to feed. We show that jellyfish exhibit a unique mechanism of passive energy recapture, which is exploited to allow them to travel 30% further each swimming cycle, thereby reducing metabolic energy demand by swimming muscles. By accounting for large interspecific differences in net metabolic rates, we demonstrate, contrary to prevailing views, that the jellyfish (Aurelia aurita) is one of the most energetically efficient propulsors on the planet, exhibiting a cost of transport (joules per kilogram per meter) lower than other metazoans. We estimate that reduced metabolic demand by passive energy recapture improves the cost of transport by 48%, allowing jellyfish to achieve the large sizes required for sufficient prey encounters. Pressure calculations, using both computational fluid dynamics and a newly developed method from empirical velocity field measurements, demonstrate that this extra thrust results from positive pressure created by a vortex ring underneath the bell during the refilling phase of swimming. These results demonstrate a physical basis for the ecological success of medusan swimmers despite their simple body plan. Results from this study also have implications for bioinspired design, where low-energy propulsion is required
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