6,950 research outputs found
Coupling of Two Motor Proteins: a New Motor Can Move Faster
We study the effect of a coupling between two motor domains in
highly-processive motor protein complexes. A simple stochastic discrete model,
in which the two parts of the protein molecule interact through some energy
potential, is presented. The exact analytical solutions for the dynamic
properties of the combined motor species, such as the velocity and dispersion,
are derived in terms of the properties of free individual motor domains and the
interaction potential. It is shown that the coupling between the motor domains
can create a more efficient motor protein that can move faster than individual
particles. The results are applied to analyze the motion of helicase RecBCD
molecules
Palliative care in Salima district
On 27th June 2007, Malawi's first dedicated palliative care centre, Ndi Moyo, was officially opened by the Honourable Marjorie Ngaunje, the then Minister of Health. Over 260 patients have registered since August 2006 when they first started to receive treatment for relief of severe and chronic pain which is frequently related to cancer (above 90% are so diagnosed). Most are terminally ill as a result of their cancer, HIV/AIDS and/or other progressive and irreversible conditions. 60% are known to be HIV positive. 40% have died within the 2 year period that the Ndi Moyo Centre has been open, but were helped to live a full life until they died.Malawi Medical Journal Vol. 20 (4) 2008: pp. 118-11
UCAC3 Proper Motion Survey. I. Discovery of New Proper Motion Stars in UCAC3 with 0.40 "/yr > mu >= 0.18 "/yr between Declinations -90 deg and -47 deg
Presented here are 442 new proper motion stellar systems in the southern sky
between declinations -90\degr and -47\degr with 0\farcs40 yr
0\farcs18 yr. These systems constitute a 25.3% increase in
new systems for the same region of the sky covered by previous SuperCOSMOS
RECONS (SCR) searches that used Schmidt plates as the primary source of
discovery. Among the new systems are 25 multiples, plus an additional seven new
common proper motion companions found to previously known primaries. All stars
have been discovered using the third U.S. Naval Observatory (USNO) CCD
Astrograph Catalog (UCAC3). A comparison of the UCAC3 proper motions to those
from the Hipparcos, Tycho-2, Southern Proper Motion (SPM4), and SuperCOSMOS
efforts is presented, and shows that UCAC3 provides similar values and
precision to the first three surveys. The comparison between UCAC3 and
SuperCOSMOS indicates that proper motions in RA are systematically shifted in
the SuperCOSMOS data but are consistent in DEC data, while overall showing a
significantly higher scatter. Distance estimates are derived for stars having
SuperCOSMOS Sky Survey (SSS) , , and plate magnitudes
and Two-Micron All Sky Survey (2MASS) infrared photometry. We find 15 systems
estimated to be within 25 pc, including UPM 1710-5300 our closest new discovery
estimated at 13.5 pc. Such new discoveries suggest that more nearby stars are
yet to be found in these slower proper motion regimes, indicating that more
work is needed to develop a complete map of the solar neighborhood.Comment: 24 pages, 7 figures, 4 tables, accepted to the Astronomical Journal
July 07, 201
A series solution and a fast algorithm for the inversion of the spherical mean Radon transform
An explicit series solution is proposed for the inversion of the spherical
mean Radon transform. Such an inversion is required in problems of thermo- and
photo- acoustic tomography. Closed-form inversion formulae are currently known
only for the case when the centers of the integration spheres lie on a sphere
surrounding the support of the unknown function, or on certain unbounded
surfaces. Our approach results in an explicit series solution for any closed
measuring surface surrounding a region for which the eigenfunctions of the
Dirichlet Laplacian are explicitly known - such as, for example, cube, finite
cylinder, half-sphere etc. In addition, we present a fast reconstruction
algorithm applicable in the case when the detectors (the centers of the
integration spheres) lie on a surface of a cube. This algorithm reconsrtucts
3-D images thousands times faster than backprojection-type methods
Gastric Diverticulum of the Prepyloric Region: A Rare Presentation of Gastric Diverticulum
Gastric diverticula are the least common diverticula of the gastrointestinal tract. The two main categories identified are congenital and acquired ones. Diverticula of the antrum, prepyloric or pyloric, are extremely rare and usually asymptomatic. We report a diverticulum of the prepyloric region in a patient with a background of peptic ulcer disease and antiplatelet treatment who became symptomatic and was treated successfully with proton pump inhibitors
Cardiorespiratory Fitness Is Inversely Associated With Clustering of Metabolic Syndrome Risk Factors: The Ball State Adult Fitness Program Longitudinal Lifestyle Study
Objective: The focus of this study was the association between the metabolic syndrome (MetSyn) and cardiorespiratory fitness (CRF) defined as maximal oxygen uptake (VO2max). Although previous research has shown a relationship between MetSyn and CRF, most studies are based on less objective measures of CRF and different cardiometabolic risk factor thresholds from earlier guidelines
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