363 research outputs found
Embodied learning at a distance: From sensory-motor experience to constructing and understanding a sine graph
Educational technologies develop quickly. Which functions of face-to-face education can be substituted by technology for distance learning? One of the risks of online education is the lack of embodied interactions. We investigate what embodied interactive technologies might offer for teaching trigonometry when learning at a distance. In a multiple case study, we analyze the potential of embodied action-based design for fostering conceptual understanding of a sine graph. It appears that independent learning with tablet-based activities leads to acquiring new sensory-motor coordinations. Some students include these new embodied experiences into mathematical discourse and trigonometry problem solving themselves, while others still need some support from a teacher. However, distantly acquired embodied experiences can be easily recalled in a few days after learning and serve well as a substrate for further conceptualization and problem-solving. The results speak for a clear contribution that embodied design might provide for grounding conceptual understanding in distance learning. However, we expect embodied design to be particularly helpful in a blended learning format
The stability of decelerating shocks revisited
We present a new method for analyzing the global stability of the Sedov-von
Neumann-Taylor self-similar solutions, describing the asymptotic behavior of
spherical decelerating shock waves, expanding into ideal gas with density
\propto r^{-\omega}. Our method allows to overcome the difficulties associated
with the non-physical divergences of the solutions at the origin. We show that
while the growth rates of global modes derived by previous analyses are
accurate in the large wave number (small wavelength) limit, they do not
correctly describe the small wave number behavior for small values of the
adiabatic index \gamma. Our method furthermore allows to analyze the stability
properties of the flow at early times, when the flow deviates significantly
from the asymptotic self-similar behavior. We find that at this stage the
perturbation growth rates are larger than those obtained for unstable
asymptotic solutions at similar [\gamma,\omega]. Our results reduce the
discrepancy that exists between theoretical predictions and experimental
results.Comment: 10 pages, 9 figures. Accepted to ApJ; Expanded discussion of boundary
condition
Risk of sudden cardiac death in strength training
Physical activity is a generally accepted means of primary and secondary prevention of cardiovascular diseases, but in some cases, it can be a risk factor for cardiovascular events, including sudden cardiac death (SCD). Most studies analyze the relationship of cardiovascular events with the volume and general directions of exercise. Besides, a significant part of the guidelines and studies are devoted to the effects of aerobic exercise, while the importance of anaerobic exercise remains controversial. The review analyzes works devoted to the influence of strength training, such as weightlifting, bodybuilding, powerlifting, etc., on the cardiovascular system, as well as their relationship with SCD and other cardiovascular events. The design and contingent of the analyzed papers did not allow them to be systematized correctly. Therefore, the review is largely analytical in nature
Minimal deformations of the commutative algebra and the linear group GL(n)
We consider the relations of generalized commutativity in the algebra of
formal series , which conserve a tensor -grading and
depend on parameters . We choose the -preserving version of
differential calculus on . A new construction of the symmetrized tensor
product for -type algebras and the corresponding definition of minimally
deformed linear group and Lie algebra are proposed. We
study the connection of and with the special matrix
algebra \mbox{Mat} (n,Q) containing matrices with noncommutative elements.
A definition of the deformed determinant in the algebra \mbox{Mat} (n,Q) is
given. The exponential parametrization in the algebra \mbox{Mat} (n,Q) is
considered on the basis of Campbell-Hausdorf formula.Comment: 14 page
MoFEM: an open source, parallel finite element library
No abstract available
MoFEM: an open source, parallel finite element library
No abstract available
The ansamycin antibiotic, rifamycin SV, inhibits BCL6 transcriptional repression and forms a complex with the BCL6-BTB/POZ domain
BCL6 is a transcriptional repressor that is over-expressed due to chromosomal translocations, or other abnormalities, in ~40% of diffuse large B-cell lymphoma. BCL6 interacts with co-repressor, SMRT, and this is essential for its role in lymphomas. Peptide or small molecule inhibitors, which prevent the association of SMRT with BCL6, inhibit transcriptional repression and cause apoptosis of lymphoma cells in vitro and in vivo. In order to discover compounds, which have the potential to be developed into BCL6 inhibitors, we screened a natural product library. The ansamycin antibiotic, rifamycin SV, inhibited BCL6 transcriptional repression and NMR spectroscopy confirmed a direct interaction between rifamycin SV and BCL6. To further determine the characteristics of compounds binding to BCL6-POZ we analyzed four other members of this family and showed that rifabutin, bound most strongly. An X-ray crystal structure of the rifabutin-BCL6 complex revealed that rifabutin occupies a partly non-polar pocket making interactions with tyrosine58, asparagine21 and arginine24 of the BCL6-POZ domain. Importantly these residues are also important for the interaction of BLC6 with SMRT. This work demonstrates a unique approach to developing a structure activity relationship for a compound that will form the basis of a therapeutically useful BCL6 inhibitor
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