Nonparametric Monitoring for Geotechnical Structures Subject to Long-Term Environmental Change

A nonparametric, data-driven methodology of monitoring for geotechnical structures subject to long-term environmental change is discussed. Avoiding physical assumptions or excessive simplification of the monitored structures, the nonparametric monitoring methodology presented in this paper provides reliable performance-related information particularly when the collection of sensor data is limited. For the validation of the nonparametric methodology, a field case study was performed using a full-scale retaining wall, which had been monitored for three years using three tilt gauges. Using the very limited sensor data, it is demonstrated that important performance-related information, such as drainage performance and sensor damage, could be disentangled from significant daily, seasonal and multiyear environmental variations. Extensive literature review on recent developments of parametric and nonparametric data processing techniques for geotechnical applications is also presented

Apoptosis Inducing Effect of Plumbagin on Colonic Cancer Cells Depends on Expression of COX-2

Plumbagin, a quinonoid found in the plants of the Plumbaginaceae, possesses medicinal properties. In this study we investigated the anti-proliferative and apoptotic activity of plumbagin by using two human colonic cancer cell lines, HT29 and HCT15. IC50 of Plumbagin for HCT15 and HT29 cells (22.5 µM and 62.5 µM, respectively) were significantly different. To study the response of cancer cells during treatment strategies, cells were treated with two different concentrations, 15 µM, 30 µM for HCT15 and 50 µM, 75 µM for HT29 cells. Though activation of NFκB, Caspases-3, elevated levels of TNF-α, cytosolic Cytochrome C were seen in both HCT15 cells HT29 treated with plumbagin, aberrant apoptosis with decreased level of pEGFR, pAkt, pGsk-3β, PCNA and Cyclin D1was observed only in 15 µM and 30 µM plumbagin treated HCT15 and 75 µM plumbagin treated HT29 cells. This suggests that plumbagin induces apoptosis in both HCT15 cells and HT29 treated, whereas, proliferation was inhibited only in 15 µM and 30 µM plumbagin treated HCT15 and 75 µM plumbagin treated HT29 cells, but not in 50 µM plumbagin treated HT29 cells. Expression of COX-2 was decreased in 75 µM plumbagin treated HT29 cells when compared to 50 µM plumbagin treated HT29 cells, whereas HCT15 cells lack COX. Hence the observed resistance to induction of apoptosis in 50 µM plumbagin treated HT29 cells are attributed to the expression of COX-2. In conclusion, plumbagin induces apoptosis in colonic cancer cells through TNF-α mediated pathway depending on expression of COX-2 expression

Filtration and drainage in geotechnical/geoenvironmental engineering/ Edit.: Reddi

vii, 204 hal.: tab.; 22 cm

Filtration and drainage in geotechnical/geoenvironmental engineering/ Edit.: Reddi

vii, 204 hal.: tab.; 22 cm

Pore Structure Variation Of Porous Media Under Vibrations

Variation of pore structures of soils due to seismic activities affects density and fluid distribution in the pores, which in turn could affect the strength and liquefaction potential of the porous media. This paper, based on experimental investigation, studied the effect of vibrations on pore sizes of porous media. A monolayer of glass beads of different sizes under full saturation condition was used to simulate porous media, and the glass beads were subjected to the vibrations provided by a small-scale shaking table. A microscopic camera, which was positioned above the glass beads and connected to a computer, captured the pore variations during the vibration at 1sec interval. Then, graphical software was employed to analyze the changes of pore size distributions before, during, and after the vibrations. The experimental study revealed that the pore size distributions of saturated and densely packed glass beads changed little before and after the vibration. During the vibration, however, the number of bigger pores decreased and the number of smaller pores increased. It may be concluded from this preliminary experimental study that although the pore structure of dense subsoil may remain relatively unchanged before and after seismic activity, the soil could experience significant change of pore structure during the vibration, which could affect the soil\u27s density, strength, and liquefaction potential. © 2008 ASCE

Finite-Depth Seepage Below Flat Aprons With Equal End Cutoffs

Although numerous studies have attempted to use data from inductive loop and radar detectors in real-time crash prediction, safety analyses that have investigated the use of traffic data from an increasingly prevalent nonintrusive surveillance system have not included the tag readers on toll roads known as automatic vehicle identification (AVI) systems. This paper (a) compares the prediction performance of a single generic model for all crashes and a specific model for rear-end crashes that used AVI data, (b) applies a Bayesian updating approach to generate full probability distributions for the coefficients, and (c) compares the estimation efficiency of the semiparametric Bayesian modeling with that of logistic regression with frequentist matched case control. A comparison of AVI data collected before all crashes and rear-end crashes with matched noncrash data revealed that rear-end crashes could be identified with a 72% accuracy, whereas the generic all-crash model achieved an accuracy of only 69% when different validation data sets were used. Moreover, the Bayesian updating approach increased the accuracy of both models by 3.5%

Closed-Form Theoretical Solution For Finite-Depth Seepage Below Flat Apron With Equal End Cutoffs And A Downstream Step

The paper gives a closed-form theoretical solution for the steady seepage below the flat horizontal impervious apron of a hydraulic structure with equal end cutoffs, with a step at the downstream end, founded on a pervious medium of finite depth. This is obtained by using Schwarz-Christoffel transformation in two stages. The numerical solution of the resulting implicit equations involving elliptic integrals gives the uplift pressures at key points, seepage discharge factor, and exit gradient factor in terms of nondimensional floor profile ratios. Design charts have been given for these seepage characteristics. © 2012 American Society of Civil Engineers

Biomimetics Of Stabilized Earth Construction: Challenges And Opportunities

This state-of-the-art paper is based on the premise that skin vasculature holds several important clues on how energy-efficiency could be accomplished in indoor environments. It is also based on the premise that stabilized earth, which has been extensively used throughout the world as a construction material, could be engineered to mimic the evolutionary developments in biology. The paper begins with a summary of recent developments in plant physiology and skin vasculature, and applies these developments in the context of stabilized earth construction. A number of interdisciplinary research opportunities are identified for communities engaged in building and energy research. This paper is developed from the proceedings of an international workshop on biomimetics of stabilized earth construction, held in Reading, UK, in March 2011. © 2012 Elsevier B.V. All rights reserved