401 research outputs found
Effects of C aenorhabditis elegans sgk‐1 mutations on lifespan, stress resistance, and DAF ‐16/ F ox O regulation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100177/1/acel12120.pd
Non-contact 3D acquisition system based on stereo vision and laser triangulation
This paper proposes a novel contact 3D acquisition system based on stereo vision and laser triangulation.
The system is composed by several software modules for data acquisition purposes, data calibration, data processing and data reconstruction of 3D scenes. Different 3D image techniques, such as, polynomial determination, cubic spline interpolation and hierarchical space decomposition were used. To validate this method, a simple laboratory prototype machine was built for the purpose of road profile acquisition, road macro and mega texture characterization. In this paper, only the results and discussion of road profile acquisition are presented.Fundação para a Ciência e a Tecnologia (FCT
Cell-based analysis of Chikungunya virus E1 protein in membrane fusion
<p>Abstract</p> <p>Background</p> <p>Chikungunya fever is a pandemic disease caused by the mosquito-borne Chikungunya virus (CHIKV). E1 glycoprotein mediation of viral membrane fusion during CHIKV infection is a crucial step in the release of viral genome into the host cytoplasm for replication. How the E1 structure determines membrane fusion and whether other CHIKV structural proteins participate in E1 fusion activity remain largely unexplored.</p> <p>Methods</p> <p>A bicistronic baculovirus expression system to produce recombinant baculoviruses for cell-based assay was used. Sf21 insect cells infected by recombinant baculoviruses bearing wild type or single-amino-acid substitution of CHIKV E1 and EGFP (enhanced green fluorescence protein) were employed to investigate the roles of four E1 amino acid residues (G91, V178, A226, and H230) in membrane fusion activity.</p> <p>Results</p> <p>Western blot analysis revealed that the E1 expression level and surface features in wild type and mutant substituted cells were similar. However, cell fusion assay found that those cells infected by CHIKV E1-H230A mutant baculovirus showed little fusion activity, and those bearing CHIKV E1-G91D mutant completely lost the ability to induce cell-cell fusion. Cells infected by recombinant baculoviruses of CHIKV E1-A226V and E1-V178A mutants exhibited the same membrane fusion capability as wild type. Although the E1 expression level of cells bearing monomeric-E1-based constructs (expressing E1 only) was greater than that of cells bearing 26S-based constructs (expressing all structural proteins), the sizes of syncytial cells induced by infection of baculoviruses containing 26S-based constructs were larger than those from infections having monomeric-E1 constructs, suggesting that other viral structure proteins participate or regulate E1 fusion activity. Furthermore, membrane fusion in cells infected by baculovirus bearing the A226V mutation constructs exhibited increased cholesterol-dependences and lower pH thresholds. Cells bearing the V178A mutation exhibited a slight decrease in cholesterol-dependence and a higher-pH threshold for fusion.</p> <p>Conclusions</p> <p>Cells expressing amino acid substitutions of conserved protein E1 residues of E1-G91 and E1-H230 lost most of the CHIKV E1-mediated membrane fusion activity. Cells expressing mutations of less-conserved amino acids, E1-V178A and E1-A226V, retained membrane fusion activity to levels similar to those expressing wild type E1, but their fusion properties of pH threshold and cholesterol dependence were slightly altered.</p
Validation of a Multivariate Serum Profile for Epithelial Ovarian Cancer Using a Prospective Multi-Site Collection
In previous studies we described the use of a retrospective collection of ovarian cancer and benign disease samples, in combination with a large set of multiplexed immunoassays and a multivariate pattern recognition algorithm, to develop an 11-biomarker classification profile that is predictive for the presence of epithelial ovarian cancer. In this study, customized, Luminex-based multiplexed immunoassay kits were GMP-manufactured and the classification profile was refined from 11 to 8 biomarkers (CA-125, epidermal growth factor receptor, CA 19-9, C-reactive protein, tenascin C, apolipoprotein AI, apolipoprotein CIII, and myoglobin). The customized kits and the 8-biomarker profile were then validated in a double-blinded manner using prospective samples collected from women scheduled for surgery, with a gynecologic oncologist, for suspicion of having ovarian cancer. The performance observed in model development held in validation, demonstrating 81.1% sensitivity (95% CI 72.6 – 87.9%) for invasive epithelial ovarian cancer and 85.4% specificity (95% CI 81.1 – 88.9%) for benign ovarian conditions. The specificity for normal healthy women was 95.6% (95% CI 83.6 – 99.2%). These results have encouraged us to undertake a second validation study arm, currently in progress, to examine the performance of the 8-biomarker profile on the population of women not under the surgical care of a gynecologic oncologist
Control Charts for Monitoring Burr Type-X Percentiles
[[abstract]]When the sampling distribution of a parameter estimator is unknown, using normality asymptotically, the Shewhart-type chart may provide improper control limits. To monitor Burr type-X percentiles, two parametric bootstrap charts (PBCs) are proposed and compared with the Shewhart-type chart via a Monte Carlo simulation. Simulation results exhibit that the proposed PBCs perform well with a short average run length to signal out-of-control when the process is out-of-control, and have more adequate control limits than the Shewhart-type chart in view of in-control false alarm rate. An example regarding single fiber strength is presented for illustrating the proposed PBCs.[[incitationindex]]SCI[[booktype]]紙
Comparison of the recording dynamics of phenanthrenequinone-doped poly(methyl methacrylate) materials
The comparison between the NCTU and Caltech PQ-PMMA material shows that the difference in their behavior lies in the different concentration of residual MMA in the samples. Experimental evidence shows that during recording, PQ molecules attach to MMA but no diffusion takes place at room temperature. However, the excess of monomer during recording enables photoinduced polymerization as a mechanism for hologram formation leading to high diffraction efficiencies without the need of baking. The grating formed by the PQ-MMA groups is unstable and it can be erased within a few hours of baking
Dynamic stabilization zone structure of jet diffusion flames from liftoff to blowout
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76733/1/AIAA-23512-341.pd
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