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MicroRNA regulation of CD8+ T cell responses.
MicroRNAs (miRNAs) are a class of short noncoding RNAs that play critical roles in the regulation of a broad range of biological processes. Like transcription factors, miRNAs exert their effects by modulating the expression of networks of genes that operate in common or convergent pathways. CD8+ T cells are critical agents of the adaptive immune system that provide protection from infection and cancer. Here, we review the important roles of miRNAs in the regulation of CD8+ T cell biology and provide perspectives on the broader emerging principles of miRNA function
Thrifty swimming with shear-thinning
Microscale propulsion is integral to numerous biomedical systems, for example
biofilm formation and human reproduction, where the surrounding fluids comprise
suspensions of polymers. These polymers endow the fluid with non-Newtonian
rheological properties, such as shear-thinning and viscoelasticity. Thus, the
complex dynamics of non-Newtonian fluids presents numerous modelling
challenges, strongly motivating experimental study. Here, we demonstrate that
failing to account for "out-of-plane" effects when analysing experimental data
of undulatory swimming through a shear-thinning fluid results in a significant
overestimate of fluid viscosity around the model swimmer C. elegans. This
miscalculation of viscosity corresponds with an overestimate of the power the
swimmer expends, a key biophysical quantity important for understanding the
internal mechanics of the swimmer. As experimental flow tracking techniques
improve, accurate experimental estimates of power consumption using this
technique will arise in similar undulatory systems, such as the planar beating
of human sperm through cervical mucus, will be required to probe the
interaction between internal power generation, fluid rheology, and the
resulting waveform
Undulatory swimming in fluids with polymer networks
The motility behavior of the nematode Caenorhabditis elegans in polymeric
solutions of varying concentrations is systematically investigated in
experiments using tracking and velocimetry methods. As the polymer
concentration is increased, the solution undergoes a transition from the
semi-dilute to the concentrated regime, where these rod-like polymers entangle,
align, and form networks. Remarkably, we find an enhancement in the nematode's
swimming speed of approximately 65% in concentrated solutions compared to
semi-dilute solutions. Using velocimetry methods, we show that the undulatory
swimming motion of the nematode induces an anisotropic mechanical response in
the fluid. This anisotropy, which arises from the fluid micro-structure, is
responsible for the observed increase in swimming speed.Comment: Published 1 November 2013 in Europhysics Letter
A New Pseudopolymorph of Hexakis-(4-cynaophenyl)benzene
The title compound (systematic name: benzene-4,4′,4′′,4′′′,-4′′′′,4′′′′′-hexaylhexabenzonitrile dichloromethane disolvate), C48H24N6•2CH2Cl2, crystallizes as an inclusion compound during the slow diffusion of methanol into a solution of hexakis(4-cyanophenyl)benzene in CH2Cl2. The hexakis(4- cyanophenyl)benzene molecule lies on an axis of twofold rotation in the space group Pbcn. Weak C—H•••N interactions between hexakis(4-cyanophenyl)benzene molecules define an open network with space for including guests. The resulting structure is a new pseudopolymorph of hexakis-(4-cyanophenyl)benzene. The eight known pseudopolymorphs have few shared architectural features, in part because none of the intermolecular interactions that are present plays a dominant role or forces neighboring molecules to assume particular relative orientations
Group classification of (1+1)-Dimensional Schr\"odinger Equations with Potentials and Power Nonlinearities
We perform the complete group classification in the class of nonlinear
Schr\"odinger equations of the form
where is an arbitrary
complex-valued potential depending on and is a real non-zero
constant. We construct all the possible inequivalent potentials for which these
equations have non-trivial Lie symmetries using a combination of algebraic and
compatibility methods. The proposed approach can be applied to solving group
classification problems for a number of important classes of differential
equations arising in mathematical physics.Comment: 10 page
X,Y,Z-Waves: Extended Structures in Nonlinear Lattices
Motivated by recent experimental and theoretical results on optical X-waves,
we propose a new type of waveforms in 2D and 3D discrete media -- multi-legged
extended nonlinear structures (ENS), built as arrays of lattice solitons (tiles
or stones, in the 2D and 3D cases, respectively). First, we study the stability
of the tiles and stones analytically, and then extend them numerically to
complete ENS forms for both 2D and 3D lattices. The predicted patterns are
relevant to a variety of physical settings, such as Bose-Einstein condensates
in deep optical lattices, lattices built of microresonators, photorefractive
crystals with optically induced lattices (in the 2D case) and others.Comment: 4 pages, 4 figure
Alien Registration- Gagnon, Joseph D. (Bar Harbor, Hancock County)
https://digitalmaine.com/alien_docs/19328/thumbnail.jp
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