Web Technologies (GGC)

This Grants Collection for Web Technologies was created under a Round Nine ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/compsci-collections/1015/thumbnail.jp

Charybdotoxin binding in the I(Ks) pore demonstrates two MinK subunits in each channel complex.

I(Ks) voltage-gated K(+) channels contain four pore-forming KCNQ1 subunits and MinK accessory subunits in a number that has been controversial. Here, I(Ks) channels assembled naturally by monomer subunits are compared to those with linked subunits that force defined stoichiometries. Two strategies that exploit charybdotoxin (CTX)-sensitive subunit variants are applied. First, CTX on rate, off rate, and equilibrium affinity are found to be the same for channels of monomers and those with a fixed 2:4 MinK:KCNQ1 valence. Second, 3H-CTX and an antibody are used to directly quantify channels and MinK subunits, respectively, showing 1.97 +/- 0.07 MinK per I(Ks) channel. Additional MinK subunits do not enter channels of monomeric subunits or those with fixed 2:4 valence. We conclude that two MinK subunits are necessary, sufficient, and the norm in I(Ks) channels. This stoichiometry is expected for other K(+) channels that contain MinK or MinK-related peptides (MiRPs)

Uniform L1L^1 error bounds for semi-discrete finite element solutions of evolutionary integral equations

summary:In this paper, we consider the second-order continuous time Galerkin approximation of the solution to the initial problem $u_{t}+\int_{0}^{t}\beta (t-s) Au(s)ds=0,u(0)=v,t>0,$ where A is an elliptic partial-differential operator and $\beta(t)$ is positive, nonincreasing and log-convex on $(0,\infty)$ with $0\leq\beta(\infty)<\beta(0^{+})\leq\infty$. Error estimates are derived in the norm of $L^{1}_{t}(0,\infty;L^{2}_{x})$, and some estimates for the first order time derivatives of the errors are also given

Ito channels are octomeric complexes with four subunits of each Kv4.2 and K+ channel-interacting protein 2.

Mammalian voltage-gated K+ channels are assemblies of pore-forming alpha-subunits and modulating beta-subunits. To operate correctly, Kv4 alpha-subunits in the heart and central nervous system require recently identified beta-subunits of the neuronal calcium sensing protein family called K+ channel-interacting proteins (KChIPs). Here, Kv4.2.KChIP2 channels are purified, integrity of isolated complexes confirmed, molar ratio of the subunits determined, and subunit valence established. A complex has 4 subunits of each type, a stoichiometry expected for other channels employing neuronal calcium sensing beta-subunits

Three-dimensional structure of I(to); Kv4.2-KChIP2 ion channels by electron microscopy at 21 Angstrom resolution.

Regulatory KChIP2 subunits assemble with pore-forming Kv4.2 subunits in 4:4 complexes to produce native voltage-gated potassium (Kv) channels like cardiac I(to) and neuronal I(A) subtypes. Here, negative stain electron microscopy (EM) and single particle averaging reveal KChIP2 to create a novel approximately 35 x 115 x 115 Angstrom, intracellular fenestrated rotunda: four peripheral columns that extend down from the membrane-embedded portion of the channel to enclose the Kv4.2 "hanging gondola" (a platform held beneath the transmembrane conduction pore by four internal columns). To reach the pore from the cytosol, ions traverse one of four external fenestrae to enter the rotundal vestibule and then cross one of four internal windows in the gondola

Describing Strong Correlation with Block-Correlated Coupled Cluster Theory

A block-correlated coupled cluster (BCCC) method based on the generalized valence bond (GVB) wave function (GVB-BCCC in short) is proposed and implemented at the ab initio level, which represents an attractive multireference electronic structure method for strongly correlated systems. The GVB-BCCC method is demonstrated to provide accurate descriptions for multiple bond breaking in small molecules, although the GVB reference function is qualitatively wrong for the studied processes. For a challenging prototype of strongly correlated systems, tridecane with all 12 single C-C bonds at various distances, our calculations have shown that the GVB-BCCC2b method can provide highly comparable results as the density matrix renormalization group method for potential energy surfaces along simultaneous dissociation of all C-C bonds

Preparation, characterization and photocatalytic activity of silicon and sulfur codoped mesoporous titanium dioxide photocatalyst

A series of mesoporous titanium dioxide (MTiO2) photocatalysts codoped with silicon and sulfur has been prepared by a template method using tetraethyl orthosilicate, thiourea and tetrabutyl titanate (Ti(OC4H9)4) as precursors and Pluronic P123 as template. The photoabsorbance of the prepared photocatalysts has been measured by UV-vis diffusive reflectance spectroscopy and its microstructure characterized using scanning electron microscopy, diffraction (XRD) and N2 adsorption-desorption measurements. The microcrystal of the codoped photocatalyst consistest of anatase phase and is present in the form of almost spherical particle. The photocatalytic activity has been studied by photodegradation of methyl blue in aqueous solution under UV and visible light irradiation. The results show that the amount of dopants, silicon and sulfur, influence the photoactivity. The photocatalyst codoped with 1 mol% silicon and 2 mol% sulfur exhibites the highest photoactivity. The synergistic effect of silicon and sulfur codoping in improves the photocatalytic activity considerably