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Most natural (or biological) materials are complex composites whose mechanical properties are often outstanding, considering the weak constituents from which they are assembled. These complex structures, which have risen from hundreds of million years of evolution, are inspiring Materials Scientists in the design of novel materials. Their defining(More)
This paper addresses signal denoising when large-amplitude coefficients form clusters (groups). The L1-norm and other separable sparsity models do not capture the tendency of coefficients to cluster (group sparsity). This work develops an algorithm, called 'overlapping group shrinkage' (OGS), based on the minimization of a convex cost function involving a(More)
Methamphetamine (METH) abuse is an increasing public health problem worldwide. Many of the METH-induced physical and mental problems are associated with the neurotoxic effects of METH. Animal studies have shown that brain-derived neurotrophic factor (BDNF) decreased after repeated amphetamine administration and increased at 30 and 90 days from(More)
This paper describes an extension to total variation denoising wherein it is assumed the first-order difference function of the unknown signal is not only sparse, but also that large values of the first-order difference function rarely occur in isolation. This approach is designed to alleviate the staircase artifact often arising in total variation based(More)
—This paper proposes a new application framework for group tour guiding services based on RFIDs and wireless sensor networks. We consider a sensing field mixed with multiple independent tourist groups, each with a leader and several members. Members of a group will follow the moving path of their leader, but may occasionally roam around randomly on their(More)
The first FPGA multiple channel digital-to-time converter, or digital pulse generator, is proposed to further extend FPGA applications into analog domain. Based on vernier principle, the effective resolution is made equivalent to the period difference of two phase-locked loop (PLL) outputs. The finer than ever DTC resolution of 1.58 ps is achieved with an(More)
Arsenic (As) is a toxic metalloid found ubiquitously in the environment and widely considered an acute poison and carcinogen. However, the molecular mechanisms of the plant response to As and ensuing tolerance have not been extensively characterized. Here, we report on transcriptional changes with As treatment in two Arabidopsis accessions, Col-0 and Ws-2.(More)
The structure and mechanical properties of the horns from a desert bighorn sheep, Ovis canadensis, were examined. Horns must be strong and durable as they are subjected to extreme loading impacts, making them superior structural materials. Horns are composed of alpha-keratin, a fibrous, structural protein found in hair, nails, claws and hooves. Horns have a(More)
Cross tolerance is a phenomenon that occurs when a plant, in resisting one form of stress, develops a tolerance to another form. Pretreatment with nonlethal heat shock has been known to protect cells from metal stress. In this study, we found that the treatment of rice roots with more than 25 muM of Cu(2+) caused cell death. However, heat shock pretreatment(More)
This paper proposes a content authentication scheme for MPEG-4 FGS (fine-granular scalability) video based on digital fragile watermarking using Bitplane-Coding Watermarking (BCW). In embedding procedure, the watermark information is embedded into every 8×8 block of residual bit-planes in the enhancement layer while encoding to MPEG-4 FGS video stream. The(More)