We investigate diffusion-limited aggregation (DLA) in a wedge geometry. Arneodo and collaborators have suggested that the ensemble average of DLA cluster density should be close to the noise-free selected Saffman-Taylor finger. We show that a different, but related, ensemble average, that of the conformal maps associated with random clusters, yields a nontrivial shape which is also not far from...

I review current results from searching for galaxies giving rise to damped Lyα absorbers (DLAs) at z < 1. Using 14 confirmed DLA galaxies, I further show that intermediate-redshift galaxies possess large H I envelope out to 24−30 h kpc radius. The photometric and spectral properties of these galaxies confirm that DLA galaxies are drawn from the typical field population, and not from a separate ...

Off-lattice diffusion-limited aggregation (DLA) clusters grown with different levels of noise reduction are found to be consistent with a simple fractal fixed point. Cluster shapes and their ensemble variation exhibit a dominant slowest correction to scaling, and this also accounts for the apparent "multiscaling" in the DLA mass distribution. We interpret the correction to scaling in terms of r...

We present the results of a search for damped Lyman-α (DLA) systems in the Sloan Digital Sky Survey II (SDSS), Data Release 7. We use a fully automatic procedure to identify DLAs and derive their column densities. The procedure is checked against the results of previous searches for DLAs in SDSS. We discuss the agreements and differences and show the robustness of our procedure. For each system...

We study the nature of damped Lyα absorption (DLA) systems at z ≤ 1 using a sample of 11 DLA galaxies, for which accurate redshift measurements are available. Five of the 11 systems are identified in our on-going photometric redshift survey of DLA galaxies, while the remaining six systems are identified by previous groups using either spectroscopic or photometric redshift techniques. Absolute B...

Diffusion-limited aggregation (DLA) is a useful model for studying such common physical phenomena as dust clustering, unstable fluid flowJ chemical species precipitation, and crystal growth. Simulating the DLA processes using electrostatic analogy is very computation-intensive. Elimination of closed loops in DLA images can significantly reduce the dimensionality of the problem and minimize the ...

This paper considers the l2-l∞ filter problem for discrete time-delay Markovian jump neural networks. Attention is focused on the design of a reduced-order filter to guarantee stochastic stability and a prescribed l2-l∞ performance for the filtering error system. In terms of linear matrix inequalities (LMIs), a delay-dependent sufficient condition for the solvability of the addressed problem is...

We examine the ‘rate-of-incidence’ distribution for damped Lyman-α absorbers (DLAs) as a function of halo mass, galaxy apparent magnitude, and impact parameter using a series of cosmological Smoothed Particle Hydrodynamics (SPH) simulations. Our simulations include radiative cooling and heating by a UV background, star formation, and feedback from supernovae and galactic winds. We find the DLA ...

We analyzed the spectroscopic and photometric database of the 5th data release of the Sloan Digital Sky Survey (SDSS) to search for evidence of the quasar reddening produced by dust embedded in intervening damped Lyα (DLA) systems. From a list of 5164 quasars in the interval of emission redshift 2.25 ≤ ze ≤ 3.5 and SDSS spectra with signal-to-noise ratio SNR ∼ 4, we built up an “absorption samp...

The role of abrin, a toxic lectin isolated from seeds of Abrus precatorius Linn in inducing apoptosis in murine Dalton's Lymphoma Ascites (DLA) cells was evaluated. Abrin when incubated at the concentration of 10 ng per million DLA cells could bring about cell death as typical morphological changes with apoptosis. However, necrotic cell death dominated when a higher dose of abrin was used. DNA ...