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Abstract We propose an approach to compute dense disparity maps that takes the characteristics of man-made environments into account. The key contribution is to generate a piecewise planar disparity map while preventing the oversimplification problem in non-planar regions. To achieve this, we decompose the stereo matching problem into three sequential subproblems: initial disparity map estimation, plane hypotheses generation, and global optimization with plane hypotheses. After finding an initial disparity map, we find local and global plane hypotheses from the disparity map through segmentation-based local plane fitting, agglomerative hierarchical clustering, and energy-based multi-model fitting techniques. We then estimate a disparity map that is a mixture of over-parameterized and scalar disparity values while identifying unreliable pixels in an energy minimization framework; disparity values in planar regions are parameterized as a plane, disparity values in non-planar regions are represented as scalar, and unreliable pixels are marked as outliers. As a post-processing step, we perturb assigned plane parameters as well as scalar disparity values. We experimentally verify the proposed method using publicly available benchmarks and various stereo matching algorithms. Highlights • We propose an approach to compute accurate disparity maps captured in man-made environments. • We find dominant planes from the scene and use them as global reconstruction cues. [ABSTRACT FROM AUTHOR]

Abstract: γ-Glutamyltranspeptidase (GGT) is a novel protein involved in the induction of Helicobacter pylori-mediated apoptosis; however, the signal pathway involved in GGT-induced apoptosis remains unclear. Using DNA recombination techniques, ggt was cloned into pET117b and transformed into Escherichia coli. Recombinant GGT was purified using nickel-affinity resin and was digested by thrombin. Recombinant GGT induced apoptosis in AGS cells in a time-dependent manner, which was confirmed by TUNEL staining, the MTT assay and immunoblot analysis for caspases-9, -3, Bax, Bcl-2, Bcl-xL and cytochrome c release. Activation of caspase-3 and -9 following exposure to GGT increased in a time-dependent manner and upregulation of proapoptotic Bax and a downregulation of antiapoptotic Bcl-2 and Bcl-xL was detected. Apoptotic signals also trigger changes in mitochondria, which lead to a release of cytochrome c into the cytosolic space. The GGT-deficient mutant was not as able to induce apoptosis as the wild-type strain. These results indicate that GGT of H. pylori induces apoptosis via a mitochondria-mediated pathway. [Copyright &y& Elsevier]

There is an urgent need for better detection and understanding of vascular abnormalities at the micro-level, where critical vascular nourishment and cellular metabolic changes occur. This is especially the case for structures such as the midbrain where both the feeding and draining vessels are quite small. Being able to monitor and diagnose vascular changes earlier will aid in better understanding the etiology of the disease and in the development of therapeutics. In this work, thirteen healthy volunteers were scanned with a dual echo susceptibility weighted imaging (SWI) sequence, with a resolution of 0.22 ​× ​0.44 ​× ​1 ​mm3 at 3T. Ultra-small superparamagnetic iron oxides (USPIO) were used to induce an increase in susceptibility in both arteries and veins. Although the increased vascular susceptibility enhances the visibility of small subvoxel vessels, the accompanying strong signal loss of the large vessels deteriorates the local tissue contrast. To overcome this problem, the SWI data were acquired at different time points during a gradual administration (final concentration ​= ​4 ​mg/kg) of the USPIO agent, Ferumoxytol, and the data was processed to combine the SWI data dynamically, in order to see through these blooming artifacts. The major vessels and their tributaries (such as the collicular artery, peduncular artery, peduncular vein and the lateral mesencephalic vein) were identified on the combined SWI data using arterio-venous maps. Dynamically combined SWI data was then compared with previous histological work to validate that this protocol was able to detect small vessels on the order of 50 ​μm–100 ​μm. A complex division-based phase unwrapping was also employed to improve the quality of quantitative susceptibility maps by reducing the artifacts due to aliased voxels at the vessel boundaries. The smallest detectable vessel size was then evaluated by revisiting numerical simulations, using estimated true susceptibilities for the basal vein and the posterior cerebral artery in the presence of Ferumoxytol. These simulations suggest that vessels as small as 50 ​μm should be visible with the maximum dose of 4 ​mg/kg. • Low dose Ferumoxytol was used in imaging the midbrain microvasculature. • Multiple timepoints provided useful temporal information and enhanced SWI-SNR. • Novel SWI combination helped reduce blooming artifacts to reveal smaller vessels. • Complex division-based unwrapping helped improve quality of post-contrast QSM. • Histology/simulations were used to determine detectability of sub-voxel vessels. [ABSTRACT FROM AUTHOR]