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To overcome the conflict between the global robustness and the local accuracy of dense nonrigid image registration, we propose a union registration approach by combining parametric and non-parametric transformation models. On one hand, to guarantee the robustness, we constrain the displacement field ϕ using a mapping difference metric between the B-spline parametric space Ψ and the non-parametric transformation space Φ. On the other hand, to correct the densely and highly localized geometrical distortions, we introduce a total variation (TV) regularization term for the displacement field ϕ. Accounting for the effect of spatially varying intensity distortions, the residual complexity (RC) is used as the similarity metric. Moreover, to solve the proposed union nonrigid registration, which is a composite convex optimization problem by the smooth ℓ2 term and the non-smooth ℓ1 term (TV), we design a two-stage algorithm using split Bregman iteration. Experiments with both synthetic and real images from different domains illustrate that this approach can capture the local details of transformation accurately and effectively while being robust to the spatially varying intensity distortions. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of generating a high-resolution (HR) image from a single degraded low-resolution (LR) input image without any external training set. Due to the ill-posed nature of this problem, it is necessary to find an effective prior knowledge to make it well-posed. For this purpose, we propose a novel super-resolution (SR) method based on combined total variation regularization. In the first place, we propose a new regularization term called steering kernel regression total variation (SKRTV), which exploits the local structural regularity properties in natural images. In the second place, another regularization term called non-local total variation (NLTV) is employed as a complementary term in our method, which makes the most of the redundancy of similar patches in natural images. By combining the two complementary regularization terms, we propose a maximum a posteriori probability framework of SR reconstruction. Furthermore, split Bregman iteration is applied to implement the proposed model. Extensive experiments demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Oxidative stress has been proved to be a critical reason of regulating CYP450s under hepatic injury status. The study was aimed to investigate the effect of pretreatment of schisandra lignan extracts (SLE) and dimethyl diphenyl bicarboxylate (DDB) on expressions and activities of the main liver P450 isoenzymes in CCl4 induced liver injury rats and their anti-oxidative effects on both CCl4 induced liver injury rats and a CCl4 induced HepG2 cell injury model. Acute experimental liver injury induced by CCl4 caused drastically decreasing activities of the main liver P450 isoenzymes such as CYP1A2, CYP2C6, CYP2E1 and CYP3A2, as well as their protein expressions. Pretreatment of SLE (500 mg/kg) and DDB (200 mg/kg) twice a day for three days significantly decreased the losses of activities of CYP1A2, CYP2C6, CYP2E1 and CYP3A2. Similar results were observed in protein expressions. In addition, in the CCl4 induced HepG2 cells injury model and the CYP3A activity level correlated well with ROS level in several ingredients of SLE treated groups, especially in γ-schisandrin group. These results indicated that the reversion of P450 after SLE/DDB treatment were, on one hand, due to hepatoprotective effects of these lignans on livers; on the other hand, due to their regulation of P450 through anti-oxidative effect and γ-schisandrin might be the most powerful ingredient of SLE. Also, there might be potential interactions between SLE or DDB and co-administered medicines and it is necessary to adjust the dosage of co-administrated medicines in clinical medication of liver disease. [ABSTRACT FROM AUTHOR]

Enzyme stability is an important issue for protein engineers. Understanding how rigidity in the active site affects protein kinetic stability will provide new insight into enzyme stabilization. In this study, we demonstrated enhanced kinetic stability of Candida antarctica lipase B (CalB) by mutating the structurally flexible residues within the active site. Six residues within 10 Å of the catalytic Ser105 residue with a high B factor were selected for iterative saturation mutagenesis. After screening 2200 colonies, we obtained the D223G/L278M mutant, which exhibited a 13-fold increase in half-life at 48 °C and a 12 °C higher T5015, the temperature at which enzyme activity is reduced to 50% after a 15-min heat treatment. Further characterization showed that global unfolding resistance against both thermal and chemical denaturation also improved. Analysis of the crystal structures of wild-type CalB and the D223G/L278M mutant revealed that the latter formed an extra main chain hydrogen bond network with seven structurally coupled residues within the flexible α10 helix that are primarily involved in forming the active site. Further investigation of the relative B factor profile and molecular dynamics simulation confirmed that the enhanced rigidity decreased fluctuation of the active site residues at high temperature. These results indicate that enhancing the rigidity of the flexible segment within the active site may provide an efficient method for improving enzyme kinetic stability. [ABSTRACT FROM AUTHOR]

Peritoneal dialysis outflow failure caused by omental wrapping is a serious complication that is difficult to diagnose noninvasively. We report a case of outflow failure in which catheterography showed several characteristics of omental wrapping: "pseudocele" formation, delayed catheter emptying, and uneven distribution of contrast in the abdominal cavity. A laparoscopic procedure was performed with identification of peritoneal adhesion and greater omental wrapping. The catheter was stripped from the omentum and repositioned in the Douglas peritoneal sac. Catheterography is a reliable, safe, noninvasive, and inexpensive alternative procedure to diagnose outflow failure caused by omental wrapping. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 is an important serotype of enterohemorrhagic E. coli that was first identified as a human pathogen in 1982. This pathogen causes several serious diseases. In this study, immunomagnetic separation was coupled with a fluorescent nanobeads lateral flow assay to establish a sensitive and rapid detection method for Escherichia coli O157:H7 in raw milk. The pathogen was captured from raw milk by immunomagnetic separation with immunomagnetic nanobeads and then detected using a fluorescent nanobeads lateral flow assay. A fluorescent line was formed in the test line of the test strip and quantitatively detected using a fluorescent reader. Screening times, which included immunomagnetic separation and the fluorescent nanobeads lateral flow assay, were 8, 7, 6, and 5 h when 1, 5, 25, and 125 cfu of E. coli O157:H7, respectively, were inoculated into 25 mL of raw milk. The established method could be widely applied to the rapid onsite detection of other pathogens to ensure food safety. [ABSTRACT FROM AUTHOR]

ISG15 (interferon-stimulated gene 15) is a novel ubiquitin-like (UbL) modifier with two UbL domains in its architecture. We investigated different roles for the two UbL domains in protein modification by ISG15 (ISGylation) and the impact of Influenza B virus NS1 protein (NS1B) on regulation of the pathway. The results show that, although the C-terminal domain is sufficient to link ISG15 to UBE1L and UbcH8, the N-terminal domain is dispensable in the activation and transthiolation steps but required for efficient E3-mediated transfer of ISG15 from UbcH8 to its substrates. NS1B specifically binds to the N-terminal domain of ISG15 but does not affect ISG15 linkage via a thioester bond to its activating and conjugating enzymes. However, it does inhibit the formation of cellular ISG15 conjugates upon interferon treatment. We propose that the N-terminal UbL domain of ISG15 mainly functions in the ligation step and NS1B inhibits ISGylation by competing with E3 ligases for bind- ing to the N-terminal domain. [ABSTRACT FROM AUTHOR]

Regioselective reaction of C60Cl6 with thioamides via a radical annulation to form fullereno thiazole derivatives is reported. The reaction is promoted by K2CO3, which might deprotonate thioamide to initiate a single electron transfer from thioamide anion to C60Cl6. The experiments with various thioamides establish the proposed base-promoted reaction as a facile route for synthesis of fullereno fused thiazole derivatives starting from C60Cl6, a prevalent synthon in fullerene chemistry. In addition, the tunable electrochemical properties of the fullereno thiazole products have been investigated for their potential photovoltaic application. [ABSTRACT FROM AUTHOR]

Huntington disease (HD) is an autosomal inherited disorder that causes the deterioration of brain cells. The polyglutamine (polyQ) expansion of huntingtin (Htt) is implicated in the pathogenesis of HD via interaction with an RNA splicing factor, Htt yeast two-hybrid protein A/forming-binding protein 11 (HYPA/FBP11). Besides the pathogenic polyQ expansion, Htt also contains a proline-rich region (PRR) located exactly in the C terminus to the polyQ tract. However, how the polyQ expansion influences the PRR-mediated protein interaction and how this abnormal interaction leads to the biological consequence remain elusive. Our NMR structural analysis indicates that the PRR motif of Htt cooperatively interacts with the tandem WW domains of HYPA through domain chaperoning effect of WW1 on WW2. The polyQ-expanded Htt sequesters HYPA to the cytosolic location and then significantly reduces the efficiency of premRNA splicing. We propose that the toxic gain-of-function of the polyQ-expanded Htt that causes dysfunction of cellular RNA processing contributes to the pathogenesis of HD. [ABSTRACT FROM AUTHOR]

Abstract: Embedded cores in a core-based system-on-chip (SOC) are not easily accessible via chip I/O pins. Test-access mechanisms (TAMs) and test wrappers (e.g., the IEEE Standard 1500 wrapper) have been proposed for the testing of embedded cores in a core-based SOC in a modular fashion. We show that such a modular testing approach can also be used for emerging three-dimensional integrated circuits based on through-silicon vias (TSVs). Core-based SOCs based on 3D IC technology are being advocated as a means to continue technology scaling and overcome interconnect-related bottlenecks. We present an optimization technique for minimizing the post-bond test time for 3D core-based SOCs under constraints on the number of TSVs, the TAM bitwidth, and thermal limits. The proposed optimization method is based on a combination of integer linear programming, LP-relaxation, and randomized rounding. It considers the Test Bus and TestRail architectures, and incorporates wire-length constraints in test-access optimization. Simulation results are presented for the ITC 02 SOC Test Benchmarks and the test times are compared to that obtained when methods developed earlier for two-dimensional ICs are applied to 3D ICs. The test time dependence on various 3D parameters (e.g. 3D placement, the number of layers, thermal constraints, and the number of TSVs) is also studied. [ABSTRACT FROM AUTHOR]