In this paper, we describe a new region-based approach to active contours for segmenting images composed of two or three types of regions characterizable by a given statistic. The essential idea is to derive curve evolutions which separate two or more values of a predetermined set of statistics computed over geometrically determined subsets of the image. Both global and local image information ...

Separation of highly similar molecules and understanding the underlying mechanism are of paramount theoretical and practical importance, but visualization of the host-guest structure, energy, or dynamism is very difficult and many details have been overlooked. Here, we report a new porous coordination polymer featuring hierarchical porosity and delicate flexibility, in which the three structura...

This article is concerned with the design and implementation of a system for real-time monocular tracking of a moving object using the two degrees of freedom of a camera platform. Figure-ground segregation is based on motion without making any a priori assumptions about the object form. Using only the first spatiotemporal image derivatives, subtraction of the normal optical flow induced by came...

The conditions of the reaction of malononitrile dimer with enaminones and arylidenemalononitrile could be adapted to yield either pyridines or benzene derivatives. A new synthesis of pyrido[1,2-a]pyrimidines from the reaction of malononitrile dimer 1 and 2-phenyl-3-piperidin-1-yl-acrylonitrile (11) is described. Compound 1 condensed with DMFDMA to yield an enaminonitrile that reacted with hydra...

An assay technique, homogeneous enzyme immunoassay, is described for the quantitative determination of morphine derivatives in biological fluids. An enzyme is labeled with morphine. When the enzymelabeled morphine is bound by antimorphine antibodies, the enzyme is rendered inactive. Free morphine competes with enzyme-morphine for antibody binding sites preventing inhibition of enzyme activity. ...

The main purpose of this paper consists of demonstrating advantages of using implicit filtering schemes (noncausal IIR filters, in the signal processing language) for some basic image processing and geometric modeling applications. In particular, applications of implicit filtering for curve subdivision, image filtering, estimating image derivatives, and deblurring Gaussian blur are considered.

In this paper, we address the problem of egomotion estimation for a monocular moving observer, under arbitrary translation and rotation. The method we propose is uniquely based on the spatio-temporal image derivatives, and has O(n 2) complexity. The approach consists in searching the image for particular geometric properties of the normal ow. The algorithm is performed in two successive steps: ...

[2+2+2] Cycloadditions can be applied to specifically build up derivatives of benzene and cyclohexadiene and, therefore, have attracted much attention. Herein, we present an intramolecular [2+2+2] cycloaddition of triynes catalyzed by the first-generation Grubbs ruthenium complex (Ru gen-1), which can efficiently afford benzene derivatives in good yields under mild conditions. Moreover, we also...

A double-wall-hourglass-shaped metallocavitand bearing an electron-deficient cavity was self-assembled, which exhibited an unusual selectivity to substituted benzene derivatives of different electron density during co-crystallizations.

We devise a statistical framework for edge detection by performing a statistical analysis of zero crossings of the second derivative of an image. This analysis enables us to estimate at each pixel of an image the probability that an edge passes through the pixel. We present a statistical analysis of the Lindeberg operators that we use to compute image derivatives. We also introduce a confidence...