1,487 research outputs found
Computation of nucleation of a non-equilibrium first-order phase transition using a rare-event algorithm
We introduce a new Forward-Flux Sampling in Time (FFST) algorithm to
efficiently measure transition times in rare-event processes in non-equilibrium
systems, and apply it to study the first-order (discontinuous) kinetic
transition in the Ziff-Gulari-Barshad model of catalytic surface reaction. The
average time for the transition to take place, as well as both the spinodal and
transition points, are clearly found by this method.Comment: 12 pages, 10 figure
IASB & FASB Convergence Project: Revenue Recognition
Accounting revenue recognition practices have a pervasive, profound impact on the financial statements of a business entity. As such, soon after committing to a plan for convergence of two major sets of accounting standards with the Norwalk Agreement of 2002, the Financial Accounting Standards Board (FASB) of the United States and the International Accounting Standards Board (IASB) undertook a project to converge their standards of revenue recognition. Through an analysis of historical practices of the two boards and progress to date on the convergence of revenue recognition standards, this paper presents further recommendation for improvement of the convergence effort. Acknowledging the progress to date, we recommend further international and industry collaboration measures to ensure that the resulting standard provides the most useful information possible to financial statement users. Progress to date along with our recommendation assure that the resulting worldwide standard of revenue recognition provides specific principle based guidance that promotes international consistency while providing the flexibility for national and industry specific application
The Condition of K-12 Public Education in Maine 2011
This book is designed to provide Maine citizens, legislators, and educators a bi-annual report on the state of Maine public schools and education. This new edition updates educational information which appeared in earlier editions, and also provides information on several new topics
Knowledge and Awareness Among Patients with Chronic Kidney Disease Stage 3
Knowledge is a prerequisite for changing behavior, and is useful for improving outcomes and reducing mortality rates in patients diagnosed with chronic kidney disease (CKD). The purpose of this article is to describe baseline CKD knowledge and awareness obtained as part of a larger study testing the feasibility of a self-management intervention. Thirty patients were recruited who had CKD Stage 3 with coexisting diabetes and hypertension. Fifty-four percent of the sample were unaware of their CKD diagnosis. Participants had a moderate amount of CKD knowledge. This study suggests the need to increase knowledge in patients with CKD Stage 3 to aid in slowing disease progression
Homeobox gene Rhox5 is regulated by epigenetic mechanisms in cancer and stem cells and promotes cancer growth
<p>Abstract</p> <p>Background</p> <p>Homeobox genes murine <it>Rhox5 </it>and human <it>RHOXF1 </it>are expressed in early embryonic stages and then mostly restricted to germline tissues in normal adult, yet they are aberrantly expressed in cancer cells <it>in vitro </it>and <it>in vivo </it>. Here we study the epigenetic regulation and potential functions of <it>Rhox5 </it>gene.</p> <p>Findings</p> <p>In <it>Rhox5 </it>-silenced or extremely low expresser cells, we observed low levels of active histone epigenetic marks (H3ac, H4ac and H3K4me2) and high levels of repressive mark H3K9me2 along with DNA hypermethylation in the promoter. In <it>Rhox5 </it>low expresser cells, we typically observed modest levels of both active and repressive histone marks along with moderate DNA methylation. In <it>Rhox5 </it>highly expressed CT26 cancer cells, we observed DNA hypomethylation along with high levels of both active and repressive histone marks. Epigenetic drugs (retinoic acid and MS-275) induced F9 cell differentiation with enhanced <it>Rhox5 </it>expression and dynamic changes of epigenetic marks. Finally, <it>Rhox5 </it>knockdown by small hairpin RNA (shRNA) in CT26 colon cancer decreased cell proliferation and migration <it>in vitro </it>and tumor growth <it>in vivo </it>.</p> <p>Conclusions</p> <p>Both DNA methylation and histone methylation/acetylation play key roles in modulating <it>Rhox5 </it>expression in various cell types. The stem cell-like "bivalent domain", an epigenetic feature originally identified in key differentiation genes within stem cells, exists in the <it>Rhox5 </it>gene promoter in not only embryonic stem cells but also cancer cells, cancer stem cells, and differentiated Sertoli cells. As <it>Ras </it>signaling-dependent <it>Rhox5 </it>expression promotes tumor growth, <it>Rhox5 </it>may be an ideal target for therapeutic intervention in cancer.</p
Myocardial thickness by gated PET and SPECT variability and bias
Proceedings of the 40th annual meeting of the Society of Nuclear Medicine, Toronto, Ontario, Canada, June 8-11, 1993Publicad
Measurement of myocardial wall thickening from PET/SPECT images: comparison of two methods
Purpose: We compared two methods for measuring myocardial wall thickening
from nuclear medicine perfusion scans. The first method uses the percent
change in peak activity, and the second method models a profile measured
across the myocardium.
Method: Mathematical simulations of the myocardium were used. In addition,
images with PET or SPECT resolution were created from real MR images.
Known amounts of noise were then added.
Results: The percent peak thickening (%PT) is nonlinear with true percent
thickening, especially for PET resolutions [7 mm full width at half-maximum
(FWHM)]. For the peak method, low levels of noise (10%) introduced an error
of 8%PT for PET and of 16%PT for SPECT. Additional smoothing reduced
these errors. For the fitted model, at 10% noise, the error in thickening was
large: 2.3 mm for PET and 7.8 mm for SPECT.
Conclusion: The fitted model works well only with good resolution and low
noise (e.g., 7 mm FWHM and 10%). The peak method is also sensitive to noise,
especially for poorer resolutions. Additional smoothing gives more reliable
results for the peak method but not the fitted method. The peak method is
therefore the more generally reliable, but even this method may only allow
classification of myocardial thickening into broad categories.Publicad
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