Polynomial-smoothing and derivative-estimating formulas for functions of one or two independent variables

Application of polynomial-smoothing formulas and related derivative-estimating formulas simplifies certain linear least-squares problems. These problems can then be solved by a computer method

A numerical ocean circulation model of the Norwegian and Greenland Seas

The dynamics and thermodynamics of the Norwegian and Greenland Seas are investigated using a three-dimensional primitive equation ocean circulation model. The horizontal resolution of the model is 1° in the zonal direction and 0.5° in the meridional direction. The vertical structure is described by 15 levels. The model is driven by both annual mean and seasonally varying wind and thermohaline forcing. The connections of the Norwegian and Greenland Seas with the North Atlantic and Arctic Ocean are modelled with an open boundary condition. The simulated currents are in reasonable agreement with the observed circulation

Magic, Mystery, Illusion and Magic

This document vaguely describes what happened to me and my paintings during my time spent at VCU

Polynomial smoothing formulas and derivative formulas for one or two independent variables

Polynomial smoothing formulas and derivative formulas for one or two independent variable

Chloride transporter KCC2-dependent neuroprotection depends on the N-terminal protein domain

Neurodegeneration is a serious issue of neurodegenerative diseases including epilepsy. Downregulation of the chloride transporter KCC2 in the epileptic tissue may not only affect regulation of the polarity of GABAergic synaptic transmission but also neuronal survival. Here, we addressed the mechanisms of KCC2-dependent neuroprotection by assessing truncated and mutated KCC2 variants in different neurotoxicity models. The results identify a threonine- and tyrosine-phosphorylation-resistant KCC2 variant with increased chloride transport activity, but they also identify the KCC2 N-terminal domain (NTD) as the relevant minimal KCC2 protein domain that is sufficient for neuroprotection. As ectopic expression of the KCC2-NTD works independently of full-length KCC2-dependent regulation of Cl(-) transport or structural KCC2 C-terminus-dependent regulation of synaptogenesis, our study may pave the way for a selective neuroprotective therapeutic strategy that will be applicable to a wide range of neurodegenerative diseases

Elektrophysiologische Charakterisierung des klassischen TRP-Kanals TRPC5

Klassische TRP-Kanäle (TRPC) sind Ca(2+)-permeable, unselektive Kationenkanäle, die durch PLC-abhängige Signalwege intrazellulär aktiviert werden. Obwohl die ersten Mitglieder dieser Subfamilie bereits vor über 15 Jahren kloniert wurden, sind sie auf funktioneller Ebene bisher nur unvollständig untersucht. Das Ziel dieser Arbeit bestand darin, die biophysikalischen Eigenschaften von TRPC5 im heterologen Expressionssystem mit Hilfe von molekularbiologischen und elektrophysiologischen Methoden im Detail zu studieren und mit denen anderer Vertreter der TRPC-Subfamilie zu vergleichen. TRPC5 wurde in der vorliegenden Arbeit als ein spannungsabhängig gesteuerter Kationenkanal herausgestellt, dessen Aktivität durch ein breites Spektrum an extrazellulären, positiv geladenen Elementarionen direkt moduliert werden kann. Die Permeation von mono- und divalenten Kationen durch TRPC5 ist unselektiv und wird durch Aminosäuren im Bereich zwischen der 5. und 6. Transmembrandomäne determiniert

Presynaptic mechanisms of neuronal plasticity and their role in epilepsy

Synaptic communication requires constant adjustments of pre- and postsynaptic efficacies. In addition to synaptic long term plasticity, the presynaptic machinery underlies homeostatic regulations which prevent out of range transmitter release. In this minireview we will discuss the relevance of selected presynaptic mechanisms to epilepsy including voltage- and ligand-gated ion channels as well as cannabinoid and adenosine receptor signaling

Ecology of the Free-Living Stages of the Lone Star Tick, Amblyomma Americanum (Linneaus)

Entomolog

Possible Mechanisms of the Exclusion of Johnson Grass by Tall Grass Prairies

Botany and Plant Patholog

Electrophysiological signature of homomeric and heteromeric glycine receptor channels

Glycine receptors are chloride-permeable, ligand-gated ion channels and contribute to the inhibition of neuronal firing in the central nervous system or to facilitation of neurotransmitter release if expressed at presynaptic sites. Recent structure-function studies provided detailed insights into the mechanisms of channel gating, desensitization and ion permeation. However, most of the work focused only on comparing few isoforms; and amongst studies, different cellular expression systems were used. Here, we performed a series of experiments using recombinantly expressed homomeric and heteromeric glycine receptor channels including their splice variants in the same cellular expression system to investigate and compare their electrophysiological properties. Our data show that the current-voltage relationships of channels formed by the {alpha}2 or {alpha}3 subunits change upon receptor desensitization from a linear to an inwardly-rectifying shape, in contrast to their heteromeric counterparts. We demonstrate that inward rectification depends on a single amino acid (A254) at the inner pore mouth of the channels and is closely linked to chloride permeation. We also show that the current-voltage relationships of glycine-evoked currents in primary hippocampal neurons are inwardly-rectifying upon desensitization. Thus, the alanine residue A254 determines voltage-dependent rectification upon receptor desensitization and provides a physio-molecular signature of homomeric glycine receptor channels which provides unprecedented opportunities for the identification of these channels at the single cell level