66 research outputs found
Plasmonic Resonances and Electromagnetic Forces Between Coupled Silver Nanowires
We compute the electromagnetic response and corresponding forces between two
silver nanowires. The wires are illuminated by a plane wave which has the
electric field vector perpendicular to the axis of the wires, insuring that
plasmonic resonances can be excited. We consider a nontrivial square cross
section geometry that has dimensions on the order of , where
is the wavelength of the incident electromagnetic field. We find that
due to the plasmonic resonance, there occurs great enhancement of the direct
and mutual electromagnetic forces that are exerted on the nanowires. The
Lippman-Schwinger volume integral equation is implemented to obtain solutions
to Maxwell's equations for various and separation distances between
wires. The forces are computed using Maxwell's stress tensor and numerical
results are shown for both on and off resonant conditions
Aqueous-Phase Synthesis of Silver Nanodiscs and Nanorods in Methyl Cellulose Matrix: Photophysical Study and Simulation of UV–Vis Extinction Spectra Using DDA Method
We present a very simple and effective way for the synthesis of tunable coloured silver sols having different morphologies. The procedure is based on the seed-mediated growth approach where methyl cellulose (MC) has been used as soft-template in the growth solution. Nanostructures of varying morphologies as well as colour of the silver sols are controlled by altering the concentration of citrate in the growth solution. Similar to the polymers in the solution, citrate ions also dynamically adsorbed on the growing silver nanoparticles and promote one (1-D) and two-dimensional (2-D) growth of nanoparticles. Silver nanostructures are characterized using UV–vis and HR-TEM spectroscopic study. Simulation of the UV–vis extinction spectra of our synthesized silver nanostructures has been carried out using discrete dipole approximation (DDA) method
The Ocean Sampling Day Consortium
Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world’s oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits
Long-term myocardial adaptations after cardiac rehabilitation in heart failure: a randomized six-year evaluation using magnetic resonance imaging
OBJECTIVE: To assess exercise capacity and left ventricular function using magnetic resonance imaging (MRI) among patients with chronic heart failure randomized to a residential rehabilitation programme at baseline and six years after participation. DESIGN: Randomized controlled study. SETTING: Residential cardiac rehabilitation centre and community hospital. INTERVENTION: One month of intensive exercise and risk reduction therapy including educational sessions, a low-fat diet, and 2 hours of individually prescribed exercise daily. Control subjects received usual care. Subjects were evaluated at baseline, after completing the one-month residential programme and six years later. SUBJECTS: From an original study group of 50, 16 patients (8 exercise, 8 controls) with chronic heart failure were alive and available for evaluation after six years. MAIN MEASURES: Cardiopulmonary exercise test responses and ventricular size and function using MRI. RESULTS: Peak Vo(2) was 20.0 and 12.4% higher after the rehabilitation programme and six years later, respectively, whereas minimal changes were observed among controls. Left ventricular mass and volumes tended to decrease among subjects in the exercise group, whereas left ventricular mass and volumes tended to increase among control subjects after six years. Ejection fraction increased approximately 20% in both groups. CONCLUSION: Six years after participation in a concentrated residential rehabilitation programme, exercise capacity was preserved and no significant changes were observed in ventricular size or function. These findings provide further support for exercise rehabilitation in chronic heart failure
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