Measuring Electric Charge and Molecular Coverage on Electrode Surface from Transient Induced Molecular Electronic Signal (TIMES).

Charge density and molecular coverage on the surface of electrode play major roles in the science and technology of surface chemistry and biochemical sensing. However, there has been no easy and direct method to characterize these quantities. By extending the method of Transient Induced Molecular Electronic Signal (TIMES) which we have used to measure molecular interactions, we are able to quantify the amount of charge in the double layers at the solution/electrode interface for different buffer strengths, buffer types, and pH values. Most uniquely, such capabilities can be applied to study surface coverage of immobilized molecules. As an example, we have measured the surface coverage for thiol-modified single-strand deoxyribonucleic acid (ssDNA) as anchored probe and 6-Mercapto-1-hexanol (MCH) as blocking agent on the platinum surface. Through these experiments, we demonstrate that TIMES offers a simple and accurate method to quantify surface charge and coverage of molecules on a metal surface, as an enabling tool for studies of surface properties and surface functionalization for biochemical sensing and reactions

Elasto-plastic Analysis of High-strength Concrete Shear Wall with Boundary Columns Using Fiber Model

In this study, an experimental study and numerical calculations using fiber model were conducted for four high-strength concrete shear walls with boundary columns under low cyclic load. The boundary column and shear wall were divided into fiber elements, and PERFORM-3D finite element analysis software was used to carry out push-over analysis on the test specimens. The results show that the finite element analysis results were in good agreement with the experimental results. The proposed analysis method could perform elasto-plastic analysis on the high-strength concrete shear wall with boundary columns without distinguishing the categories of frame column and shear wall. The seismic performance of high-strength concrete shear wall with boundary columns was analyzed using the following parameters: axis compression ratio, height to width ratio, ratio of vertical reinforcement, and ratio of longitudinal reinforcement in the boundary column. The results show that the increase in the axial compression ratio causes the bearing capacity of the shear wall to increase at first and then to decrease and causes the ductility to decrease. The increase in the height to width ratio causes the bearing capacity of the shear wall to decrease and its ductility to increase. The ratio of vertical reinforcement was found to have little effect on the bearing capacity and ductility. The increase in the ratio of longitudinal reinforcement in boundary column resulted in a significant increase in the bearing capacity and caused the ductility to decrease at first and then to slowly increase

Genetic diversity and character association analysis based on pomological traits in olive (Olea europaea L.)

Thirteen exotic genotypes of olive (Olea europaea L.) were studied for the genetic variability, correlation and path coefficient analysis for fruit quality, yield and yield contributing traits at experimental farm of ICAR-CITH, Srinagar during 2009-2013. Maximum variability was recorded for fruit yield and oil content, however, low differ-ences between the phenotypic and genotypic coefficients of variations indicated low environmental influences on the expression of these characters. High heritability coupled with high genetic advance was obtained with fruit yield per plant, acidity, fruit pulp weight, fruit weight and stone weight. Fruit weight (r=0.329), stone weight (r=0.405) and oil content (r=0.841) were the most important traits, which possessed significant positive association with fruit yield per plant. Path coefficient analysis revealed that among the different yield contributing characters oil content (0.875), fruit weight (0.797) followed by acidity (0.501), peroxides value ( 0.199) and fruit length (0.054) influenced fruit yield per plant directly. The direct effects of these characters on fruit yield were found positive and considerably very high.The selection based on fruit weight, stone weight oil content and yield per plant will be effective for enhancing the fruit and oil yieldand making future olive breeding strategies

Lipopolysaccharide preconditioning enhances the efficacy of mesenchymal stem cells transplantation in a rat model of acute myocardial infarction

<p>Abstract</p> <p>Background</p> <p>Mesenchymal stem cells (MSCs)-based regenerative therapy is currently regarded as an alternative approach to salvage the acute myocardial infarcted hearts. However, the efficiency of MSCs transplantation is limited by lower survival rate of engrafted MSCs. In previous study, we found that 1.0 μg/ml Lipopolysaccharide (LPS) could protect MSCs against apoptosis induced by oxidative stress and meanwhile enhance the proliferation of MSCs. Therefore, in the present study, we firstly preconditioned MSCs with 1.0 μg/ml LPS, then transplanted MSCs into ischemic myocardium, and observed the survival and cardiac protective capacity of MSCs in a rat model of acute myocardial infarction. Furthermore, we tried to explore the underlying mechanisms and the role of Toll-like receptor-4 (TLR4) in the signal pathway of LPS-induced cardiac protection.</p> <p>Methods and results</p> <p>Acute myocardial infarction model was developed by left anterior descending coronary artery ligation. 60 rats were divided into 4 groups randomly and given an intramyocardial injection of one of the following treatments: 30 μl PBS (control group), 3 × 10⁶wild MSCs/30 μl (wMSCs group), 3 × 10⁶LPS-preconditioned wild MSCs/30 μl (LPS-wMSCs group), or 3 × 10⁶LPS-preconditioned TLR4 gene deleted MSCs/30 μl (LPS-tMSCs group). After 3 weeks, LPS-preconditioned wild MSCs transplantation ameliorated cardiac function and reduced fibrosis of infarcted myocardium. Vascular density was markedly increased in LPS-wMSCs group compared with other three groups. Survival rate of engrafted MSCs was elevated and apoptosis of myocardium was reduced in infarcted heart. Expression of vascular endothelial growth factor (VEGF) and phospho-Akt was increased in the infarcted myocardium after transplantation of LPS-preconditioned MSCs.</p> <p>Conclusion</p> <p>LPS preconditioning enhanced survival of engrafted MSCs, stimulated expression of VEGF and activated PI3K/Akt pathway. LPS preconditioning before MSCs transplantation resulted in superior therapeutic neovascularization and recovery of cardiac function. LPS preconditioning provided a novel strategy in maximizing biologic and functional properties of MSCs.</p