Et B/Et AlCl/O -Mediated Radical Coupling Reaction between α-Alkoxyacyl Tellurides and 2-Hydroxybenzaldehyde Derivatives.

A newly devised radical-based strategy enabled coupling between multiply oxygenated α-alkoxyacyl tellurides and 2-hydroxybenzaldehyde derivatives. A reagent combination of Et B, Et AlCl, and O promoted the formation of the α-alkoxy carbon radical from the α-alkoxyacyl telluride and the addition of the radical to the carbonyl group of 2-hydroxybenzaldehyde. The reaction chemo- and stereoselectively forged the hindered C-C bond between two oxygen-functionalized carbons at ambient temperature.

A new synthetic route to 5,6,11,12-tetraarylethynyltetracenes.

A new synthetic route to 5,6,11,12-tetrakis(arylethynyl)tetracenes, π-extended rubrenes, was developed via [4 + 2] cycloadditions of dialkynylisobenzofuran and 1,4-naphthoquinone. Introduction of arylethynyl groups by double nucleophilic additions to tetracenequinone gave sterically congested (arylethynyl)tetracenes after reductive aromatization. The photophysical properties of the newly prepared π-conjugated molecules are also evaluated.

Three-dimensional inverse synthetic aperture lidar imaging for long-range spinning targets.

We present a three-dimensional (3D) imaging method for long-range spinning targets. This method acquires multi-angle two-dimensional (2D) images of spinning targets by the inverse synthetic aperture lidar (ISAL) imaging technique. The 3D distribution of the scattering coefficients of a target has a mapping relationship with the series of 2D images.

Inverse synthetic aperture LADAR demonstration: system structure, imaging processing, and experiment result.

A long-distance inverse synthetic aperture LADAR (ISAL) imaging experiment outdoors over 1 km for cooperative targets is demonstrated, which gets a two-dimensional high-resolution image with resolution exceeding 2.5 cm. The system utilizes an electro-optic in-phase and quadrature modulator to output a linear frequency-modulated continuous waveform (LFMCW) with a bandwidth of 6 GHz and pulse repetition frequency (PRF) of 16.

Linear frequency-modulated continuous-wave ladar system for synthetic aperture imaging.

A novel and high-efficiency linear frequency-modulated continuous-wave (FMCW) ladar system for synthetic aperture imaging is proposed and experimentally demonstrated. This novel system generates wide-bandwidth linear FMCW ladar signals by employing an electro-optic LiNbO- in-phase and quadrature modulator with an effective bias controller. The effectiveness of the proposed system is experimentally validated.

A general framework for biclustering gene expression data.

A large number of biclustering methods have been proposed to detect patterns in gene expression data. All these methods try to find some type of biclusters but no one can discover all the types of patterns in the data. Furthermore, researchers have to design new algorithms in order to find new types of biclusters/patterns that interest biologists.

Efficient and robust feature extraction by maximum margin criterion.

In pattern recognition, feature extraction techniques are widely employed to reduce the dimensionality of data and to enhance the discriminatory information. Principal component analysis (PCA) and linear discriminant analysis (LDA) are the two most popular linear dimensionality reduction methods. However, PCA is not very effective for the extraction of the most discriminant features, and LDA is not stable due to the small sample size problem.

Minimum entropy clustering and applications to gene expression analysis.

Clustering is a common methodology for analyzing the gene expression data. In this paper, we present a new clustering algorithm from an information-theoretic point of view. First, we propose the minimum entropy (measured on a posteriori probabilities) criterion, which is the conditional entropy of clusters given the observations.

Robust and accurate cancer classification with gene expression profiling.

Robust and accurate cancer classification is critical in cancer treatment. Gene expression profiling is expected to enable us to diagnose tumors precisely and systematically. However, the classification task in this context is very challenging because of the curse of dimensionality and the small sample size problem.