Theoretical and Experimental Studies of Schottky Diodes That Use Aligned Arrays of Single Walled Carbon Nanotubes

We present theoretical and experimental studies of Schottky diodes that use aligned arrays of single walled carbon nanotubes. A simple physical model, taking into account the basic physics of current rectification, can adequately describe the single-tube and array devices. We show that for as grown array diodes, the rectification ratio, defined by the maximum-to-minimum-current-ratio, is low due to the presence of m-SWNT shunts. These tubes can be eliminated in a single voltage sweep resulting in a high rectification array device. Further analysis also shows that the channel resistance, and not the intrinsic nanotube diode properties, limits the rectification in devices with channel length up to ten micrometer.Comment: Nano Research, 2010, accepte

Prospect and potential of Burkholderia sp. against Phytophthora capsici Leonian: a causative agent for foot rot disease of black pepper

Foot rot disease is a very destructive disease in black pepper in Malaysia. It is caused by Phytophthora capsici Leonian, which is a soilborne pathogenic protist (phylum, Oomycota) that infects aerial and subterranean structures of many host plants. This pathogen is a polycyclic, such that multiple cycles of infection and inoculum production occur in a single growing season. It is more prevalent in the tropics because of the favourable environmental conditions. The utilization of plant growth-promoting rhizobacteria (PGPR) as a biological control agent has been successfully implemented in controlling many plant pathogens. Many studies on the exploration of beneficial organisms have been carried out such as Pseudomonas fluorescens, which is one of the best examples used for the control of Fusarium wilt in tomato. Similarly, P. fluorescens is found to be an effective biocontrol agent against the foot rot disease in black pepper. Nowadays there is tremendous novel increase in the species of Burkholderia with either mutualistic or antagonistic interactions in the environment. Burkholderia sp. is an indigenous PGPR capable of producing a large number of commercially important hydrolytic enzymes and bioactive substances that promote plant growth and health; are eco-friendly, biodegradable and specific in their actions; and have a broad spectrum of antimicrobial activity in keeping down the population of phytopathogens, thus playing a great role in promoting sustainable agriculture today. Hence, in this book chapter, the potential applications of Burkholderia sp. to control foot rot disease of black pepper in Malaysia, their control mechanisms, plant growth promotion, commercial potentials and the future prospects as indigenous PGPR were discussed in relation to sustainable agriculture

A computational framework for complex disease stratification from multiple large-scale datasets.

BACKGROUND: Multilevel data integration is becoming a major area of research in systems biology. Within this area, multi-'omics datasets on complex diseases are becoming more readily available and there is a need to set standards and good practices for integrated analysis of biological, clinical and environmental data. We present a framework to plan and generate single and multi-'omics signatures of disease states. METHODS: The framework is divided into four major steps: dataset subsetting, feature filtering, 'omics-based clustering and biomarker identification. RESULTS: We illustrate the usefulness of this framework by identifying potential patient clusters based on integrated multi-'omics signatures in a publicly available ovarian cystadenocarcinoma dataset. The analysis generated a higher number of stable and clinically relevant clusters than previously reported, and enabled the generation of predictive models of patient outcomes. CONCLUSIONS: This framework will help health researchers plan and perform multi-'omics big data analyses to generate hypotheses and make sense of their rich, diverse and ever growing datasets, to enable implementation of translational P4 medicine

Excess sound velocity and excess specific acoustic impedance of (2,2,2-trifluoroethan-1-01 +benzene), (benzene+dimethyl sulphoxide) and (2,2,2-trifluoroethan-1-01+dimethyl sulphoxide) at 298.15 K

301-305Excess sound velocity (UE) and excess specific acoustic impedance (ZE) have been evaluated in binary liquid mixtures: 2.2.2-trifluoroethan-1-O1+benzene, benzene + dimethyl sulphoxide and 2.2.2-tritluoroethan-1-O1+dimethyl sulphoxide at 298.15 K. The results are discussed in the light of molecular interactions in these mixtures and compared with the other excess thermodynamic data available in literature. The liquid state theories have been applied to predict the sound velocities in these mixtures. </span

Polyethylene glycol enhances <i>in vitro </i>germination and tube growth of oil palm pollen

169-172Sucrose or boric acid used by earlier workers for in vitro germination of oil palm pollen has not been satisfactory as germination is inconsistent, pollen tubes are short and show several abnormalities. Incorporation of polyethylene glycol (PEG 10,000) resulted in consistent and good germination, with long and normal pollen tubes. The best response was obtained on a medium containing sucrose (2.5%)+boric acid (100 ppm)+PEG (10%) in which pollen tubes were over 10 times longer than those in the medium without PEG. Use of PEG as a component of pollen germination medium for other species is suggested

Areca husk: An inexpensive substrate for citric acid production by Aspergillus niger under solid state fermentation

99-102Areca husk was used as a substrate for the production of citric acid under solid state fermentation (SSF) using a new local soil isolate of Aspergillus niger. A. niger produced 119.42±2.5 g citric acid/kg dry areca husk fermented in the presence of 3% w/w methanol at optimum pH 5.0, 50 % moisture content and 30oC incubation temperature in 3 d. The citric acid yield was 66.7±1% based on the amount of fermentable sugars consumed during fermentation

Preparation, Characterization and Spectroscopic Investigations of PEOX-PVOH Blend Films

A stable and free standing polymer blend films of poly (2-ethyl-2-oxazoline) [PEOX] and poly(vinyl alcohol) [PVOH] were prepared by solution casting technique at different weight percentages (70/30, 50/50, 30/70). The prepared blends were characterized by scanning electron microscopy (SEM), and ultraviolet-visible (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy. Various optical properties such as absorption band edge, direct and indirect band gap, and optical activation energy were obtained by UV-Vis spectral analysis. FTIR analysis confirms the specific hydrogen bonding between –CH3 groups of PEOX and –OH groups of PVOH, and also the hydrophilic nature of the blends