Development and use of iron oxide nanoparticles (Part 1): Synthesis of iron oxide nanoparticles for MRI

Contrast agents, such as iron oxide, enhance MR images by altering the relaxation times of tissues in which the agent is present. They can also be used to label targeted molecular imaging probes. Unfortunately, no molecular imaging probe is currently available on the clinical MRI market. A promising platform for MRI contrast agent development is nanotechnology, where superparamagnetic iron oxide nanoparticles (SPIONS) are tailored for MR contrast enhancement, and/or for molecular imaging. SPIONs can be produced using a range of methods and the choice of method will be influenced by the characteristics most important for a particular application. In addition, the ability to attach molecular markers to SPIONS heralds their application in molecular imaging

Rapid Coverage of Regions of Interest for Environmental Monitoring

We present a framework for rapidly determining regions of interest (ROIs) from an unknown intensity distribution, particularly in radiation fields. The vast majority of studies on area coverage path planning for mobile robots do not investigate the identification of ROIs. In a radiation field, the use of ROIs can limit the required range of exploration and mitigate the monitoring problem. However, considering that an unmanned aerial vehicle (UAV) has limited resources as a mobile measurement system, it is challenging to determine ROIs in unknown radiation fields. Given a target area, we attempt to plan a path that facilitates the localization of ROIs with a single UAV while minimizing the exploration cost. To reduce the complexity of a large-scale environment exploration, entire areas are initially adaptively decomposed using two hierarchical methods based on recursive quadratic subdivision and Voronoi-based subdivision. Once an informative decomposed subarea is selected by maximizing a utility function, the robot heuristically reaches contaminated areas, and a boundary estimation algorithm is adopted to estimate the environmental boundaries. The properties of this boundary estimation algorithm are theoretically analyzed in this paper. Finally, the detailed boundaries of the ROIs of the target area are approximated by ellipses, and a set of procedures are iterated to sequentially cover all areas. The simulation results demonstrate that our framework allows a single UAV to efficiently explore a given target area and maximize the localization rate for ROIs

Review on enzymatic synthesis of value added products of glycerol, a by-product derived from biodiesel production

Crude glycerol is produced as a by-product from biodiesel production via trans-esterification with methanol and this process accounts for 10% (w/w) of the total biodiesel produced worldwide. The glycerol glut created can be utilized to increase biodiesel profitability since disposal can pose a threat to the environment. The need is to transform this surplus crude glycerol into added-value products. Biological based conversions are efficient in providing products that are drop-in replacements for petro-chemicals and offer functionality advantage, commanding higher price with the potential to increase bio-refinery revenue. Glycerol is a stable and multifunctional compound used as a building block in fine chemical synthesis like bio-polymers, polyunsaturated fatty acids, ethanol, hydrogen, n-butanol, glycerol carbonate, glycerol acetyl esters etc. Bio-catalysts add higher value to bio based products by catalyzing not only their selective modification, but also their synthesis under controlled and mild conditions. This article focuses on different bioconversion technologies of crude-glycerol to value added industrial products â obtained as waste from current bio-diesel production. We abridge the recent relevant approach for the production of various platform chemicals from bio-glycerol over enzyme and chemical catalysts. Keywords: Enzyme catalysis, Bio-glycerol, Renewable chemicals, Green processes, Bio-refiner