Unraveling Complex Local Protein Environments with 4-Cyano-l-phenylalanine.

We present a multifaceted approach to effectively probe complex local protein environments utilizing the vibrational reporter unnatural amino acid (UAA) 4-cyano-l-phenylalanine (pCNPhe) in the model system superfolder green fluorescent protein (sfGFP). This approach combines temperature-dependent infrared (IR) spectroscopy, X-ray crystallography, and molecular dynamics (MD) simulations to provide a molecular interpretation of the local environment of the nitrile group in the protein. Specifically, a two-step enantioselective synthesis was developed that provided an 87% overall yield of pCNPhe in high purity without the need for chromatography.

A Modular Scaffold for Controlling Transcriptional Activation via Homomeric Protein-Protein Interactions.

Protein-protein interactions (PPIs) have been extensively utilized in synthetic biology to construct artificial gene networks. However, synthetic regulation of gene expression by PPIs in has largely relied upon repressors, and existing PPI-controlled transcriptional activators have generally been employed with heterodimeric interactions. Here we report a highly modular, PPI-dependent transcriptional activator, cCadC, that was designed to be compatible with homomeric interactions.

Enzyme directed evolution using genetically encodable biosensors.

Directed evolution has been remarkably successful in identifying enzyme variants with new or improved properties, such as altered substrate scope or novel reactivity. Genetically encodable biosensors (GEBs), which convert the concentration of a small molecule ligand into an easily detectable output signal, have seen increasing application to enzyme directed evolution in the last decade. GEBs enable the use of high-throughput methods to assess enzyme activity of very large libraries, which can accelerate the search for variants with desirable activity.

Early Seizure Detection by Applying Frequency-Based Algorithm Derived from the Principal Component Analysis.

The use of automatic electrical stimulation in response to early seizure detection has been introduced as a new treatment for intractable epilepsy. For the effective application of this method as a successful treatment, improving the accuracy of the early seizure detection is crucial. In this paper, we proposed the application of a frequency-based algorithm derived from principal component analysis (PCA), and demonstrated improved efficacy for early seizure detection in a pilocarpine-induced epilepsy rat model.

Sequential Change of Wound Calculated by Image Analysis Using a Color Patch Method during a Secondary Intention Healing.

Background: Photographs of skin wounds have the most important information during the secondary intention healing (SIH). However, there is no standard method for handling those images and analyzing them efficiently and conveniently.

Objective: To investigate the sequential changes of SIH depending on the body sites using a color patch method.

Defocus and geometric distortion correction for projected images on a curved surface.

In this paper, a correction method of defocus and geometric distortion for projected images on nonideal projection surfaces is proposed. To offer distortion-free images on curved projection surfaces, a camera captures the projected image to estimate the distortion. To compensate for defocus, which is due to the change in distance from the projector to the projection surface, the space varying point-spread function of the projector is modeled using a thin lens model.

Poisson-Gaussian Noise Reduction Using the Hidden Markov Model in Contourlet Domain for Fluorescence Microscopy Images.

In certain image acquisitions processes, like in fluorescence microscopy or astronomy, only a limited number of photons can be collected due to various physical constraints. The resulting images suffer from signal dependent noise, which can be modeled as a Poisson distribution, and a low signal-to-noise ratio. However, the majority of research on noise reduction algorithms focuses on signal independent Gaussian noise.

Estimation of multiexponential fluorescence decay parameters using compressive sensing.

Fluorescence lifetime imaging microscopy (FLIM) is a microscopic imaging technique to present an image of fluorophore lifetimes. It circumvents the problems of typical imaging methods such as intensity attenuation from depth since a lifetime is independent of the excitation intensity or fluorophore concentration. The lifetime is estimated from the time sequence of photon counts observed with signal-dependent noise, which has a Poisson distribution.

Perturbation of quadric transfer due to deformation of curved screen displays.

Non-planar screens are increasingly used in mobile projectors and virtual reality environments. When the screen is modeled as a second order polynomial, a quadric transfer method can be employed to compensate for image distortion. This method uses the quadric matrix that models 3D surface information of a quadric screen.

Local in vivo shimming using adaptive passive shim positioning.

A subject-specific local in vivo passive shimming method, focusing on the prefrontal and temporal regions, is proposed. The aim of the investigation is to show that subject variability exists in optimal passive shimming and that the proposed method can be effectively used to overcome these differences. A shimming structure capable of adjusting the position of the passive shims to within a millimeter resolution is built.

A novel 3-D color histogram equalization method with uniform 1-D gray scale histogram.

The majority of color histogram equalization methods do not yield uniform histogram in gray scale. After converting a color histogram equalized image into gray scale, the contrast of the converted image is worse than that of an 1-D gray scale histogram equalized image. We propose a novel 3-D color histogram equalization method that produces uniform distribution in gray scale histogram by defining a new cumulative probability density function in 3-D color space.