scholarly journals Direct Observation of Axial Dynamics of Particle Manipulation With Weber Self-Accelerating Beams

2021 ◽  
Vol 9 ◽  
Author(s):  
Sha An ◽  
Tong Peng ◽  
Shaohui Yan ◽  
Baoli Yao ◽  
Peng Zhang
Keyword(s):  
Real Time ◽  
Imaging System ◽  
Optical Tweezer ◽  
Axial Plane ◽  
Objective Lens ◽  
Research Fields ◽  
Micro Particles ◽  
Lateral Plane ◽  
Time Observation ◽  
And Control

Optical manipulation of micro-particles with nondiffracting and self-accelerating beams has been successfully applied in many research fields such as chemicophysics, material sciences and biomedicine. Such operation mainly focuses on the particle transport and control in the beam propagation direction. However, the conventional optical microscopy is specifically designed for obtaining the sample information located in the lateral plane, which is perpendicular to the optical axis of the detecting objective lens, making the real-time observation of particle dynamics in axial plane a challenge. In this work, we propose and demonstrate a technique which integrates a special beam optical tweezer with a direct axial plane imaging system. Here, particles are transported in aqueous solution along a parabolic trajectory by a designed nonparaxial Weber self-accelerating beam, and the particle motion dynamics both in lateral and axial plane are monitored in real-time by the axial plane imaging technique.

scholarly journals Real-Time In Vivo Bioluminescent Imaging for Evaluating the Efficacy of Antibiotics in a Rat Staphylococcus aureus Endocarditis Model

2005 ◽  
Vol 49 (1) ◽  
pp. 380-387 ◽  
Author(s):  
Yan Q. Xiong ◽  
Julie Willard ◽  
Jagath L. Kadurugamuwa ◽  
Jun Yu ◽  
Kevin P. Francis ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Real Time ◽  
Imaging System ◽  
Bioluminescent Imaging ◽  
Vancomycin Therapy ◽  
Treatment Groups ◽  
Highly Sensitive ◽  
Relevant Animal Model ◽  
And Control

ABSTRACT Therapeutic options for invasive Staphylococcus aureus infections have become limited due to rising antimicrobial resistance, making relevant animal model testing of new candidate agents more crucial than ever. In the present studies, a rat model of aortic infective endocarditis (IE) caused by a bioluminescently engineered, biofilm-positive S. aureus strain was used to evaluate real-time antibiotic efficacy directly. This strain was vancomycin and cefazolin susceptible but gentamicin resistant. Bioluminescence was detected and quantified daily in antibiotic-treated and control animals with IE, using a highly sensitive in vivo imaging system (IVIS). Persistent and increasing cardiac bioluminescent signals (BLS) were observed in untreated animals. Three days of vancomycin therapy caused significant reductions in both cardiac BLS (>10-fold versus control) and S. aureus densities in cardiac vegetations (P < 0.005 versus control). However, 3 days after discontinuation of vancomycin therapy, a greater than threefold increase in cardiac BLS was observed, indicating relapsing IE (which was confirmed by quantitative culture). Cefazolin resulted in modest decreases in cardiac BLS and bacterial densities. These microbiologic and cardiac BLS differences during therapy correlated with a longer time-above-MIC for vancomycin (>12 h) than for cefazolin (∼4 h). Gentamicin caused neither a reduction in cardiac S. aureus densities nor a reduction in BLS. There were significant correlations between cardiac BLS and S. aureus densities in vegetations in all treatment groups. These data suggest that bioluminescent imaging provides a substantial advance in the real-time monitoring of the efficacy of therapy of invasive S. aureus infections in live animals.

scholarly journals Real-time observation and control of optical chaos

2021 ◽  
Vol 7 (3) ◽  
pp. eabc8448
Author(s):  
Linran Fan ◽  
Xiaodong Yan ◽  
Han Wang ◽  
Lihong V. Wang
Keyword(s):  
Real Time ◽  
Chaotic System ◽  
Chaotic Systems ◽  
Central Research ◽  
Optical Chaos ◽  
Propagation Of Light ◽  
Phase Map ◽  
Time Observation ◽  
And Control ◽  
Real Time Observation

Optical chaotic system is a central research topic due to its scientific importance and practical relevance in key photonic applications such as laser optics and optical communication. Because of the ultrafast propagation of light, all previous studies on optical chaos are based on either static imaging or spectral measurement, which shows only time-averaged phenomena. The ability to reveal real-time optical chaotic dynamics and, hence, control its behavior is critical to the further understanding and engineering of these systems. Here, we report a real-time spatial-temporal imaging of an optical chaotic system, using compressed ultrafast photography. The time evolution of the system’s phase map is imaged without repeating measurement. We also demonstrate the ability to simultaneously control and monitor optical chaotic systems in real time. Our work introduces a new angle to the study of nonrepeatable optical chaos, paving the way for fully understanding and using chaotic systems in various disciplines.

Real Time Observation and Characterization of Dislocation Motion, Nitrogen Desorption and Nanopipe Formation in GaN

2000 ◽  
Vol 622 ◽  
Author(s):  
Eric A. Stach ◽  
C.F. Kisielowski ◽  
W.S. Wong ◽  
T. Sands ◽  
N.W. Cheung
Keyword(s):  
Real Time ◽  
Defect Formation ◽  
Hydride Vapor Phase Epitaxy ◽  
Objective Lens ◽  
Thermal Stimulus ◽  
Contrast Imaging ◽  
Nitrogen Desorption ◽  
Lift Off ◽  
Time Observation ◽  
Real Time Observation

ABSTRACTDespite the considerable attention focused on GaN and related alloys during the past decade, many outstanding questions remain regarding the mechanisms of defect formation in these materials. In this work, we take advantage of a recently developed processing technique known as laser lift-off to examine the behavior of thin, free-standing, nearly stress-free single crystals of GaN subjected to thermal stimulus. GaN layers of 7 νm thickness were removed from their sapphire growth substrate using the laser lift-off method, then ion-milled to electron transparency. The samples were then annealed at temperatures between 850 and 1025 °C within the objective lens of a 200 kV transmission electron microscope. This allowed real time observation of defect formation via diffraction contrast imaging. Above 925 °C nitrogen desorption first becomes visible at the thinnest edges of the TEM sample. Concomitant with this is the preferential desorption of nitrogen along the cores of those dislocations which are pure screw in character, resulting in the formation of nanopipes. In regions with small residual stresses, those dislocations with mixed edge and screw components propagate parallel to the basal plane in the three close-packed {1 1 00} directions, leaving a hollow tube in their wake. At these temperatures, no motion of dislocations with pure edge character is observed. These results indicate that desorption and plasticity may occur simultaneously in these materials. Additionally, it appears that nanopipe formation may be unavoidable during heteroepitaxial growth by chemical vapor deposition and hydride vapor phase epitaxy, as these deposition methods require substrate temperatures of this magnitude.

scholarly journals Nanoscopic live electrooptic imaging

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masahiro Tsuchiya ◽  
Shigeru Takata ◽  
Kazuhiro Ohsone ◽  
Shinji Fukui ◽  
Muneo Yorinaga
Keyword(s):  
Electric Field ◽  
Real Time ◽  
Imaging System ◽  
Objective Lens ◽  
Peak Splitting ◽  
Sensor Film ◽  
Video Images ◽  
Field Distributions ◽  
Oil Immersion ◽  
Real Time Visualization

AbstractA door to the nanoscopic domain is opened regarding real-time visualization of electric field distributions and dynamics. Through the use of a live electrooptic imaging system with an oil-immersion objective lens and a highly thinned electrooptic sensor film, a minimum linewidth of 330 nm and a minimum peak splitting of 650 nm in real-time electric field video images have been successfully demonstrated. In addition, room to improve the resolution is noted, while a few problems that need to be solved are discussed, including an effect caused by optical interference.

scholarly journals Real-time dispersal of malaria vectors in rural Africa monitored with lidar

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247803
Author(s):  
Samuel Jansson ◽  
Elin Malmqvist ◽  
Yeromin Mlacha ◽  
Rickard Ignell ◽  
Fredros Okumu ◽  
...  
Keyword(s):  
Real Time ◽  
Malaria Vector ◽  
Malaria Vectors ◽  
Malaria Vector Control ◽  
Vector Ecology ◽  
Spatio Temporal ◽  
Time Observation ◽  
And Control ◽  
The Village

Lack of tools for detailed, real-time observation of mosquito behavior with high spatio-temporal resolution limits progress towards improved malaria vector control. We deployed a high-resolution entomological lidar to monitor a half-kilometer static transect positioned over rice fields outside a Tanzanian village. A quarter of a million in situ insect observations were classified, and several insect taxa were identified based on their modulation signatures. We observed distinct range distributions of male and female mosquitoes in relation to the village periphery, and spatio-temporal behavioral features, such as swarming. Furthermore, we observed that the spatial distributions of males and females change independently of each other during the day, and were able to estimate the daily dispersal of mosquitoes towards and away from the village. The findings of this study demonstrate how lidar-based monitoring could dramatically improve our understanding of malaria vector ecology and control options.

Imaging and Motion Prediction for an Automated Live-Bird Transfer Process

2000 ◽  
Author(s):  
Kok-Meng Lee ◽  
Jeffry Joni ◽  
Xuecheng Yin
Keyword(s):  
Real Time ◽  
Transfer Process ◽  
Imaging System ◽  
Motion Prediction ◽  
Design Evaluation ◽  
Transfer System ◽  
Structured Illumination ◽  
Prediction And Control ◽  
And Control ◽  
Live Bird

Abstract This paper presents the illumination design of a real-time live-bird imaging system for determining the size and initial presentation of a bird on a moving conveyor. A real-time live-bird imaging system presents a challenging design problem, for it must minimize the variability of the birds’ visual reflexes to mechanical processes, it must account for variations in bird size/shape/color, it must meet the cycle-time requirement, and yet provide an adequately illuminated environment to ease human supervision. In this paper, we first identify the variables needed for motion prediction. Second, by analyzing the bird visual perception we have developed a two-stage structured illumination that has the potential to minimize the demand on the control efforts of the transfer system, and to improve birds’ welfare and the ultimate product quality. Finally, we present the image algorithms and experimental results of the design evaluation using live birds. It is expected that the design principles presented in this paper provide essential bases for motion analysis, prediction, and control of an automated live-bird transfer process.

Real-time flat-panel pixel imaging system and control for X-ray and neutron detection

2001 ◽  
Vol 48 (6) ◽  
pp. 2357-2364 ◽  
Author(s):  
S. Chapuy ◽  
M. Dimcovski ◽  
Z. Dimcovski ◽  
E.H. Lehmann ◽  
M. Pachoud ◽  
...  
Keyword(s):  
Real Time ◽  
Imaging System ◽  
Neutron Detection ◽  
Flat Panel ◽  
X Ray ◽  
And Control

Real-Time Observation and Control of Pentacene Film Growth on an Artificially Structured Substrate

2009 ◽  
Vol 21 (48) ◽  
pp. 4996-5000 ◽  
Author(s):  
Yuki Tsuruma ◽  
Abdullah Al-Mahboob ◽  
Susumu Ikeda ◽  
Jerzy T. Sadowski ◽  
Genki Yoshikawa ◽  
...  
Keyword(s):  
Real Time ◽  
Film Growth ◽  
Time Observation ◽  
And Control ◽  
Real Time Observation

A Superconducting Microscope

1971 ◽  
Vol 29 ◽  
pp. 10-11 ◽  
Author(s):  
R. E. Worsham ◽  
J. E. Mann ◽  
E. G. Richardson
Keyword(s):  
Liquid Helium ◽  
Focal Length ◽  
Vacuum System ◽  
Objective Lens ◽  
Electrical Instability ◽  
Radiation Shields ◽  
And Control ◽  
Thermal Oscillations ◽  
Flux Pump

This superconducting microscope, Figure 1, was first operated in May, 1970. The column, which started life as a Siemens Elmiskop I, was modified by removing the objective and intermediate lenses, the specimen chamber, and the complete vacuum system. The large cryostat contains the objective lens and stage. They are attached to the bottom of the 7-liter helium vessel and are surrounded by two vapor-cooled radiation shields.In the initial operational period 5-mm and 2-mm focal length objective lens pole pieces were used giving magnification up to 45000X. Without a stigmator and precision ground pole pieces, a resolution of about 50-100Å was achieved. The boil-off rate of the liquid helium was reduced to 0.2-0.3ℓ/hour after elimination of thermal oscillations in the cryostat. The calculated boil-off was 0.2ℓ/hour. No effect caused by mechanical or electrical instability was found. Both 4.2°K and 1.7-1.9°K operation were routine. Flux pump excitation and control of the lens were quite smooth, simple, and, apparently highly stable. Alignment of the objective lens proved quite awkward, however, with the long-thin epoxy glass posts used for supporting the lens.

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