Combined First- and Second-Order Variational Model for Image Compressive Sensing

A hybrid variational model combined first- and second-order total variation for image reconstruction from its finite number of noisy compressive samples is proposed in this paper. Inspired by majorization-minimization scheme, we develop an efficient algorithm to seek the optimal solution of the proposed model by successively minimizing a sequence of quadratic surrogate penalties. Both the nature and magnetic resonance (MR) images are used to compare its numerical performance with four state-of-the-art algorithms. Experimental results demonstrate that the proposed algorithm obtained a significant improvement over related state-of-the-art algorithms in terms of the reconstruction relative error (RE) and peak signal to noise ratio (PSNR)

Poly[[diaqua-μ2-4,4′-bipyridyl-μ2-o-phthalato-nickel(II)] dihydrate]

In the title layer complex, {[Ni(C8H4O4)(C10H8N2)(H2O)2]·2H2O}n, the Ni atom has a distorted octa­hedral environment, defined by the phthalate and 4,4′-bipyridyl ligands which link the Ni atoms, forming a square lattice in the bc plane. This extends into a three-dimensional supra­molecular network through O—H⋯O hydrogen-bonding inter­actions. The Ni atom lies on, and both ligands are bis­ected by, a crystallographic twofold axis

3-Phosphoinositide-dependent Protein Kinase-1 (PDK1) promotes invasion and activation of matrix metalloproteinases

BACKGROUND: Metastasis is a major cause of morbidity and mortality in breast cancer with tumor cell invasion playing a crucial role in the metastatic process. PDK1 is a key molecule that couples PI3K to cell proliferation and survival signals in response to growth factor receptor activation, and is oncogenic when expressed in mouse mammary epithelial cells. We now present evidence showing that PDK1-expressing cells exhibit enhanced anchorage-dependent and -independent cell growth and are highly invasive when grown on Matrigel. These properties correlate with induction of MMP-2 activity, increased MT1-MMP expression and a unique gene expression profile. METHODS: Invasion assays in Matrigel, MMP-2 zymogram analysis, gene microarray analysis and mammary isografts were used to characterize the invasive and proliferative function of cells expressing PDK1. Tissue microarray analysis of human breast cancers was used to measure PDK1 expression in invasive tumors by IHC. RESULTS: Enhanced invasion on Matrigel in PDK1-expressing cells was accompanied by increased MMP-2 activity resulting from stabilization against proteasomal degradation. Increased MMP-2 activity was accompanied by elevated levels of MT1-MMP, which is involved in generating active MMP-2. Gene microarray analysis identified increased expression of the ECM-associated genes decorin and type I procollagen, whose gene products are substrates of MT1-MMP. Mammary fat pad isografts of PDK1-expressing cells produced invasive adenocarcinomas. Tissue microarray analysis of human invasive breast cancer indicated that PDK1pSer241 was strongly expressed in 90% of samples. CONCLUSION: These results indicate that PDK1 serves as an important effector of mammary epithelial cell growth and invasion in the transformed phenotype. PDK1 mediates its effect in part by MT1-MMP induction, which in turn activates MMP-2 and modulates the ECM proteins decorin and collagen. The presence of increased PDK1 expression in the majority of invasive breast cancers suggests its importance in the metastatic process

A three-dimensional finite element modelling of human chest injury following front or side impact loading

Based on anatomical features of a 50th percentile adult male, three-dimensional (3D) finite element (FE) models of ribs, sternum, vertebrae, intervertebral discs, clavicle, scapula, pelvis, skin, head, muscles and limbs were developed in this study. After integrating/assembling various organs and tissues, a bio-mechanical FE model of the human body with adult male characteristics was produced. Furthermore, a chest frontal and lateral collision theory model was built and was validated by using previously published data from corpse frontal and lateral chest impact collision experiments. Good agreements were found between the simulation results of our model and the experimental data as well as theoretical calculations in the contact force, sternum displacement, and force-displacement response. These data suggest that this 3D FE model is effective and has good bio-fidelity in assessing chest biomechanical responses and thoracic injuries upon impact loading. Therefore this model can potentially be useful for evaluating thoracic injuries in car crashes and assessing chest rib fractures and internal organ/tissue damages

Poly[bis­(2,2′-bipyridine-κ2 N,N′)deca-μ-oxido-dioxidodicopper(II)tetra­vanadium(V)]

The title compound, [Cu2V4O12(C10H8N2)2]n, shows a two-dimensional copper–vanadate layer composed of eight-membered rings, each containing four corner-sharing VO4 tetra­hedra; these are linked through six penta­coordinated CuII atoms with the 2,2′-bipyridine ligands attached and pointing above and below the plane of the layer. The Cu atom is coordinated by two N donors from the 2,2′-bipyridine ligand and three O atoms from three adjacent VO4 units to form a distorted tetragonal pyramid. These layers are further connected by π–π inter­actions between inter­leaving bipyridine ligands of adjacent layers [centroid–centroid distances = 3.63 (1) and 3.68 (1) Å] into a three-dimensional supra­molecular structure