7,278 research outputs found
Determination of Hydrogen Diffusion Parameters of Ferritic Steel from Electrochemical Permeation Measurement under Tensile Loads
The hydrogen permeation experiment, performed with a stepwise permeation sequence involving "1st permeation-desorption-2nd permeation under loading, demonstrates that fine blister cracks are frequently observed on the steel surface in hydrogen charging side after the 2nd permeation under the load over 95% of yield strength of the steel. To accommodate the experimental phenomena under the loading conditions, a numerical model is developed for determination of hydrogen diffusion parameters of the sour-resistant ferritic steel evaluated under tensile stress in plastic ranges. To solve the modified diffusion equation, a numerical finite difference method (FDM) is employed. The diffusion parameters determined by curve-fitting with the newly proposed diffusion equation indicates that, with the transition of mechanical domain from local-plasticity to generalized-plasticity, a big increase in the crack formation rate and hydrogen capture rate per irreversible trap are observed. It suggests that the transition probability for hydrogen transport from interstitial lattice site to irreversible trap site increases with the stress level. (C) The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. All rights reserved.1110Ysciescopu
Presumed pseudokinase VRK3 functions as a BAF kinase
Vaccinia-related kinase 3 (VRK3) is known as a pseudokinase that is catalytically inactive due to changes in motifs that are essential for kinase activity. Although VRK3 has been regarded as a genuine pseudokinase from structural and biochemical studies, recent reports suggest that VRK3 acts as an active kinase as well as a signaling scaffold in cells. Here, we demonstrate that VRK3 phosphorylates the nuclear envelope protein barrier-to-autointegration factor (BAF) on Ser4. Interestingly, VRK3 kinase activity is dependent upon its N-terminal regulatory region, which is excluded from the determination of its crystal structure. Furthermore, the kinase activity of VRK3 is involved in the regulation of the cell cycle. VRK3 expression levels increase during interphase, whereas VRK1 is enriched in late G2 and early M phase. Ectopic expression of VRK3 induces the translocation of BAF from the nucleus to the cytoplasm. In addition, depletion of VRK3 decreases the population of proliferating cells. These data suggest that VRK3-mediated phosphorylation of BAF may facilitate DNA replication or gene expression by facilitating the dissociation of nuclear envelope proteins and chromatin during interphase. (C) 2015 Elsevier B.V. All rights reserved.1174Ysciescopu
Emerging evidence for CHFR as a cancer biomarker : from tumor biology to precision medicine
Novel insights in the biology of cancer have switched the paradigm of a "one-size-fits-all" cancer treatment to an individualized biology-driven treatment approach. In recent years, a diversity of biomarkers and targeted therapies has been discovered. Although these examples accentuate the promise of personalized cancer treatment, for most cancers and cancer subgroups no biomarkers and effective targeted therapy are available. The great majority of patients still receive unselected standard therapies with no use of their individual molecular characteristics. Better knowledge about the underlying tumor biology will lead the way toward personalized cancer treatment. In this review, we summarize the evidence for a promising cancer biomarker: checkpoint with forkhead and ring finger domains (CHFR). CHFR is a mitotic checkpoint and tumor suppressor gene, which is inactivated in a diverse group of solid malignancies, mostly by promoter CpG island methylation. CHFR inactivation has shown to be an indicator of poor prognosis and sensitivity to taxane-based chemotherapy. Here we summarize the current knowledge of altered CHFR expression in cancer, the impact on tumor biology and implications for personalized cancer treatment
A Reaction Between High Mn-High Al Steel and CaO-SiO2-Type Molten Mold Flux: Part I. Composition Evolution in Molten Mold Flux
In order to elucidate the reaction mechanism between high Mn-high Al steel such as twin-induced plasticity steel and molten mold flux composed mainly of CaO-SiO2 during continuous casting process, a series of laboratory-scale experiments were carried out in the present study. Molten steel and molten flux were brought to react in a refractory crucible in a temperature range between 1713 K to 1823 K (1440 A degrees C to 1550 A degrees C) and composition evolution in the steel and the flux was analyzed using inductively coupled plasma atomic emission spectroscopy, X-ray fluorescence, and electron probe microanalysis. The amount of SiO2 in the flux was significantly reduced by Al in the steelthus, Al2O3 was accumulated in the flux as a result of a chemical reaction, 4[Al] + 3(SiO2) = 3[Si] + 2(Al2O3). In order to find a major factor which governs the reaction, a number of factors ((pct CaO/pct SiO2), (pct Al2O3), [pct Al], [pct Si], and temperature) were varied in the experiments. It was found that the above chemical reaction was mostly governed by [pct Al] in the molten steel. Temperature had a mild effect on the reaction. On the other hand, (pct CaO/pct SiO2), (pct Al2O3), and [pct Si] did not show any noticeable effect on the reaction. Apart from the above reaction, the following reactions are also thought to happen simultaneously: 2[Mn] + (SiO2) = [Si] + 2(MnO) and 2[Fe] + (SiO2) = [Si] + 2(FeO). These oxide components were subsequently reduced by Al in the molten steel. Na2O in the molten flux was gradually decreased and the decrease was accelerated by increasing [pct Al] and temperature. Possible reactions affecting the Al2O3 accumulation are summarized.ope
OASIS 2: online application for survival analysis 2 with features for the analysis of maximal lifespan and healthspan in aging research
Online application for survival analysis (OASIS) has served as a popular and convenient platform for the statistical analysis of various survival data, particularly in the field of aging research. With the recent advances in the fields of aging research that deal with complex survival data, we noticed a need for updates to the current version of OASIS. Here, we report OASIS 2 (http://sbi.postech.ac.kr/oasis2), which provides extended statistical tools for survival data and an enhanced user interface. In particular, OASIS 2 enables the statistical comparison of maximal lifespans, which is potentially useful for determining key factors that limit the lifespan of a population. Furthermore, OASIS 2 provides statistical and graphical tools that compare values in different conditions and times. That feature is useful for comparing age-associated changes in physiological activities, which can be used as indicators of "healthspan." We believe that OASIS 2 will serve as a standard platform for survival analysis with advanced and user-friendly statistical tools for experimental biologists in the field of aging research.1127Ysciescopu
C. elegans maximum velocity correlates with healthspan and is maintained in worms with an insulin receptor mutation
Ageing is marked by physical decline. Caenorhabditis elegans is a valuable model for identifying genetic regulatory mechanisms of ageing and longevity. Here we report a simple method to assess C. elegans' maximum physical ability based on the worms' maximum movement velocity. We show maximum velocity declines with age, correlates well with longevity, accurately reports movement ability and, if measured in mid-adulthood, is predictive of maximal lifespan. Contrary to recent findings, we observe that maximum velocity of worm with mutations in daf-2(e1370) insulin/IGF-1 signalling scales with lifespan. Because of increased odorant receptor expression, daf-2(e1370) mutants prefer food over exploration, causing previous on-food motility assays to underestimate movement ability and, thus, worm health. Finally, a disease-burden analysis of published data reveals that the daf-2(e1370) mutation improves quality of life, and therefore combines lifespan extension with various signs of an increased healthspan.114232Ysciescopu
KIAA1114, a full-length protein encoded by the trophinin gene, is a novel surface marker for isolating tumor-initiating cells of multiple hepatocellular carcinoma subtypes
Identification of novel biomarkers for tumor-initiating cells (TICs) is of critical importance for developing diagnostic and therapeutic strategies against cancers. Here we identified the role of KIAA1114, a full-length translational product of the trophinin gene, as a distinctive marker for TICs in human liver cancer by developing a DNA vaccine-induced monoclonal antibody targeting the putative extracellular domain of KIAA1114. Compared with other established markers of liver TICs, KIAA1114 was unique in that its expression was detected in both alpha fetoprotein (AFP)-positive and AFP-negative hepatocellular carcinoma (HCC) cell lines with the expression levels of KIAA1114 being positively correlated to their tumorigenic potentials. Notably, KIAA1114 expression was strongly detected in primary hepatic tumor, but neither in the adjacent non-tumorous tissue from the same patient nor normal liver tissue. KIAA1114(high) cells isolated from HCC cell lines displayed TIC-like features with superior functional and phenotypic traits compared to their KIAA1114(low) counterparts, including tumorigenic abilities in xenotransplantation model, in vitro colony- and spheroid-forming capabilities, expression of stemness-associated genes, and migratory capacity. Our findings not only address the value of a novel antigen, KIAA1114, as a potential diagnostic factor of human liver cancer, but also as an independent biomarker for identifying TIC populations that could be broadly applied to the heterogeneous HCC subtypes.X1110Nsciescopu
Topography optimization of an enclosure panel for low-frequency noise and vibration reduction using the equivalent radiated power approach
An enclosure panel is widely used in industrial applications. The panel under a dynamic loading excites the surrounding air medium and noise is radiated into the acoustic space. The radiated sound can be suppressed by having changes in the structure. The noise reduction performance can be further improved by a design optimization. In this study, a topography optimization is conducted to design an enclosure panel. Topography optimization results in a bead pattern, which helps maintain the thickness at a constant level throughout the structure. The final optimized structure can be manufactured using a stamping process. Compared with other optimization methods, topography optimization requires minimal manufacturing effort and cost, with no additional increase in mass. Moreover, this type of optimization is effective for noise reduction problems because no holes are created in the structure. In this study, the objective function selected to minimize the low-frequency noise is the equivalent radiated power. The topography optimization of the enclosure panel has been conducted using the commercial software Altair OptiStruct, with loads and constraints considered. In order to verify the optimization result, in-situ experiment was performed with panels produced by the stamping process
Firing frequency response to current and conductance periodic inputs in a Ih/INap biophysical neuron model
Size Matters: Microservices Research and Applications
In this chapter we offer an overview of microservices providing the
introductory information that a reader should know before continuing reading
this book. We introduce the idea of microservices and we discuss some of the
current research challenges and real-life software applications where the
microservice paradigm play a key role. We have identified a set of areas where
both researcher and developer can propose new ideas and technical solutions.Comment: arXiv admin note: text overlap with arXiv:1706.0735
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