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The present article investigates whether the drag coefficient of low density objects can be determined by free fall experiments with sufficient accuracy. Among other things, the drag coefficient depends on the flow velocity, which can be controlled in wind channels experiments. Free fall experiments do not offer an experimental environment with constant flow velocity. Especially the later part of the movement gets relevantly influenced by air drag deceleration. We theoretically estimate an average sphere drag coefficient for the relevant part of the movement of falling spheres. The results are verified by examining the drag coefficient from experimental data. Finally, we determine the drag coefficient of a model rocket, which is compared to the result of the corresponding wind channel experiment.

The use of salt-tolerant plant growth promoting rhizobacteria (ST-PGPR) for reducing environmental stress and enhancing quality of crops has recently emerged as a perspective for sustainable development of agriculture, especially in the context of climate change. Within the mining of potential bacterial candidates serving for such purposes, bacterial strains from rhizosphere of mangrove plants in Vietnam were isolated and characterized. Results revealed two microbial isolates from Sonneratia caseolaris, symbolized as S13 and S15, exhibited 1-aminocyclopropane-l-carboxylic acid (ACC) deaminase activity and salt tolerance up to 7% sodium chloride. These bacteria performed phosphate solubilizing property with 57.04-61.16% of degradation after 9 days in NBRIP medium. Besides, S13 and S15 showed antimicrobial activity against plant pathogens, including F. oxysporum and A. niger. By analyzing the ribosomal 16S sequences, bacterial strains S13 and S15 were identified to be Bacillus spp. with phylogenetically close relation to B. velezensis and B. siamensis, respectively. Additionally, sprouts encoated with S13 and S15 bacterial suspensions (~4*108 CFU/L each) exhibited enhanced shoot and root elongation in both normal and saline conditions. The bacterial strains were in vitro evaluated to be nontoxic to tested cells and animals. Achieved results brought out mangrove derived ST-PGPR strains with highly applicable potential for development of saline agriculture. [ABSTRACT FROM AUTHOR]

A miniature integrated optical coherence tomography (OCT) - ultrasound (US) probing system for real-time intravascular imaging has been developed. The outer diameter of the integrated probe is 0.69 mm, which is small enough for imaging in human coronary arteries. This probe, which has high resolution and deep tissue penetration, is designed to identify vulnerable atherosclerotic plaques in coronary arteries. The first in vivo images of a rabbit abdominal aorta obtained by the integrated OCT-US probe are presented. © 2012 SPIE.

Intracoronary optical coherence tomography (OCT) and intravascular ultrasound (IVUS) are two popular techniques for the detection and determination of atherosclerosis. IVUS allows visualization of plaques while also providing a large penetration depth to determine plaque volume. Intracoronary OCT provides the ability to capture microscopic features associated with high risk plaque. Traditionally to utilize the benefits of both modalities, separate probes and systems had to be used one at a time to image a vessel. We present work required to create a combined OCT IVUS system capable of simultaneous imaging to detect atherosclerotic plaques. A novel integrated probe of size 0.69 mm OD featuring sequential placement of components was created to acquire co-registered images within small coronary vessels. By utilizing commercial graphics processing units (GPUs) real time visualization of acquired data is possible up to a maximum 48 frames per second per channel. In vitro studies on human coronary artery samples as well as in vivo studies in rabbits and pigs show various plaque buildups in both OCT and IVUS images which match histology results, demonstrating the capabilities of the system. © 2012 SPIE.

We report on the development of a multimodal optical coherence tomography (OCT) - ultrasound (US) system and miniaturized OCT-US probe for intravascular imaging. Both OCT optical components and a US transducer were integrated into a single probe, enabling both OCT and US imaging at the same time. A miniaturized OCT-US probe using a single element transducer was designed with a maximum outer diameter of 0.8 mm, which is suitable for in vivo intravascular imaging. The integrated OCT-US imaging system adopted a two-channel data acquisition card to digitize both OCT and US signals. Simultaneous OCT and US data processing and image display were also achieved using our home-developed software. In vitro OCT and US imaging of human aortic tissue was performed using this multimodal imaging system, which demonstrated the feasibility of the OCT-US system in intravascular imaging and its potential in detection of atherosclerotic plaques. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

A gas-puff magnetically insulated ion diode is under development as a pulsed source of high-energy alpha particles for magnetic fusion experiments. The diode is patterned after the Cornell gas-puff diode [J. B. Greenly, M. Ueda, G. D. Rondeau, and D. A. Hammer, J. Appl. Phys. 63, 1872 (1988)], but with modifications to accomodate higher voltages (

Rajesh K Rajpal, Bryan Ross, Sachin D Rajpal, Khoa HoangSee Clearly Vision Group, McLean, VA, USAAbstract: Ophthalmic nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used by clinicians to manage ocular inflammation and pain following cataract surgery. Over the past decade, the US Food and Drug Administration has approved multiple topical NSAIDs for these purposes, including several reformulated products. One of these medications, bromfenac ophthalmic solution, has a long and extensive history, with proven efficacy and safety in patients following cataract surgery. The evolution of bromfenac ophthalmic solution over the years has involved either lowering the concentration of the active ingredient or extending the dosing interval to improve patient adherence/compliance. This review will focus on the history and progression of bromfenac ophthalmic solution and report the available patient preference and adherence data regarding this ocular NSAID throughout its evolution.Keywords: cataract surgery, nonsteroidal anti-inflammatory drugs, COX inhibitors

Background: Smoking media literacy (SML) has been found to be independently associated with reduced current smoking and reduced susceptibility to future smoking in a sample of American adolescents, but not in other populations of adolescents. Thus, the purpose of this study was to assess SML in Vietnamese adolescents and to determine the association with smoking behavior and susceptibility to future smoking. Methods: A cross-sectional survey of 2000 high school students completed the SML scale, which is based on an integrated theoretical framework of media literacy, and items assessing cigarette use. Ordinal logistic regression was used to determine the association of SML with smoking and susceptibility to future smoking. Ordinal logistic regression was also to determine whether smoking in the past 30 days was associated with the 8 domains/core concepts of media literacy which comprise the SML. Results: Smoking media literacy was lower among the Vietnamese adolescents than what has been previously reported in American adolescents. Ordinal logistic regression analysis results showed that in the total sample SML was associated with reduced smoking, but there was no association with susceptibility to future smoking. Further analysis showed that results differed according to school and grade level. There did not appear to be association of smoking with the specific domains/concepts that comprise the SML. Conclusions: The association of SML with reduced smoking suggests the need for further research involving SML, including the testing of media literacy training interventions, in Vietnamese adolescents and also other populations of adolescents. (Contains 5 tables.)