An ion channel protein begins life as a nascent peptide inside a ribosome, moves to the endoplasmic reticulum where it becomes integrated into the lipid bilayer, and ultimately forms a functional unit that conducts ions in a well-regulated fashion. Here, I discuss the nascent peptide and its tasks as it wends its way through ribosomal tunnels and exit ports, through translocons, and into the bi...

Understanding substrate binding and product release in cytochrome P450 (CYP) enzymes is important for explaining their key role in drug metabolism, toxicity, xenobiotic degradation and biosynthesis. Here, molecular simulations of substrate and product exit from the buried active site of a mammalian P450, the microsomal CYP2C5, identified a dominant exit channel, termed pathway (pw) 2c. Previous...

This paper considers the performance and design of a reduced complexity iterative equalizer, for a system including a rate one recursive channel precoder. Recursive channel precoders have been shown to yield significant performance gains, in wireless communication systems, if designed correctly. Extrinsic information transfer (EXIT) charts are used to predict system performance and as a configu...

In this contribution a coherent (2x2) (multiple input multiple output) MIMO transmission with iterative detection over a measured multimode fiber channel at 1325 nm operating wavelength is studied. For the channel measurements a fibre length of 1,4 km was chosen. Extrinsic information transfer (EXIT) charts are used for analyzing and optimizing the convergence behaviour of the iterative demappi...

This paper uses the mutual information (MI) transfer metric to characterize the behavior of an adaptive turbo equalization scheme. We consider recursive systematic convolutional coding at the input to a multipath fastfading channel. The equalizer is a recent adaptive, nearoptimal APP algorithm that incorporates MMSE channel estimation. We develop design rules for this turbo equalizer using EXIT...

Physical layer network coding (PNC) is a promising technique to improve the network throughput in a two-way relay (TWR) channel for two users to exchange messages across a wireless network. The PNC technique incorporating a TWR channel is embraced by a free space optical (FSO) communication link for full utilization of network resources, namely TWR-FSO PNC. In this paper, bit interleaved coded ...

Escherichia coli heat stable enterotoxin (STa) caused Cl- secretion across T84 cell monolayers in a dose-dependent manner only when applied to the apical membrane surface and not when applied to the basolateral surface. Measurement of cAMP, cGMP, and free cytosolic Ca2+ in response to STa suggested that cGMP alone mediated the Cl- secretory response. Studies utilizing blockers of the Na+,K+-ATP...

Consider coded transmission over a binary-input symmetric memoryless channel. The channel decoder uses the noisy observations of the code symbols to reproduce the transmitted code symbols. Thus, it combines the information about individual code symbols to obtain an overall information about each code symbol, which may be the reproduced code symbol or its a-posteriori probability. This tutorial ...

This paper evaluates a mutual-information integral that appears in EXIT-chart analysis and the capacity equation for the binaryinput AWGN channel. Rapidly-converging series representations are derived and shown to be computationally efficient. Over a wide range of channel signal-to-noise ratios, the series are more accurate than the Gauss-Hermite quadrature and comparable to Monte Carlo integra...