Three-dimensional Multicolor Subcellular Imaging by Fast Serial Sectioning Tomography for Centimeter-scale Specimens

Rapid multicolor three-dimensional (3D) imaging for centimeter-scale specimens with subcellular resolution remains a challenging but captivating scientific pursuit. Here, we present a fast, automated, cost-effective, and versatile multicolor 3D imaging method with ultraviolet (UV) surface excitation and vibratomy-assisted sectioning, termed translational rapid ultraviolet-excited sectioning tomography (TRUST). TRUST enables exogenous molecular-specific fluorescence and endogenous content-rich autofluorescence imaging simultaneously with the help of a UV light-emitting diode and a color camera. Commonly applied tissue preparation procedures (e.g., staining or clearing) are laborious, time-consuming, and may induce detrimental effects on processed samples. In TRUST, formalin-fixed specimens are stained with real-time double labeling layer by layer along with serial widefield optical illumination with raster scanning and mechanical sectioning to improve the staining speed and reveal rich biological information. All vital organs in mice have been imaged by TRUST to demonstrate its fast, robust, and high-content multicolor 3D imaging ability. Moreover, its potential for developmental biology has also been validated by imaging entire mouse embryos (taking ~2 days for imaging the embryo at the embryonic day of 15). TRUST offers a way for multicontrast and multicolor whole-organ 3D imaging with high resolution and high speed while relieving researchers from heavy sample preparation workload.

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High-speed volumetric two-photon fluorescence imaging of neurovascular dynamics

Nature Communications ◽

10.1038/s41467-020-19851-1 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Jiang Lan Fan ◽

Jose A. Rivera ◽

Wei Sun ◽

John Peterson ◽

Henry Haeberle ◽

...

Keyword(s):

Blood Flow ◽

High Speed ◽

Laser Scanning ◽

Three Dimensional ◽

Laser Scanning Microscopy ◽

Fluorescence Signal ◽

Imaging Method ◽

Spatiotemporal Resolution ◽

Two Photon

AbstractUnderstanding the structure and function of vasculature in the brain requires us to monitor distributed hemodynamics at high spatial and temporal resolution in three-dimensional (3D) volumes in vivo. Currently, a volumetric vasculature imaging method with sub-capillary spatial resolution and blood flow-resolving speed is lacking. Here, using two-photon laser scanning microscopy (TPLSM) with an axially extended Bessel focus, we capture volumetric hemodynamics in the awake mouse brain at a spatiotemporal resolution sufficient for measuring capillary size and blood flow. With Bessel TPLSM, the fluorescence signal of a vessel becomes proportional to its size, which enables convenient intensity-based analysis of vessel dilation and constriction dynamics in large volumes. We observe entrainment of vasodilation and vasoconstriction with pupil diameter and measure 3D blood flow at 99 volumes/second. Demonstrating high-throughput monitoring of hemodynamics in the awake brain, we expect Bessel TPLSM to make broad impacts on neurovasculature research.

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Evaluation of Parts Produced by a Novel Additive Manufacturing Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.315.63 ◽

2013 ◽

Vol 315 ◽

pp. 63-67 ◽

Cited By ~ 1

Author(s):

Muhammad Fahad ◽

Neil Hopkinson

Keyword(s):

Additive Manufacturing ◽

Rapid Prototyping ◽

Manufacturing Process ◽

High Speed ◽

Three Dimensional ◽

Coordinate Measuring Machine ◽

Layer By Layer ◽

Nylon 12 ◽

Measuring Machine ◽

End Use

Rapid prototyping refers to building three dimensional parts in a tool-less, layer by layer manner using the CAD geometry of the part. Additive Manufacturing (AM) is the name given to the application of rapid prototyping technologies to produce functional, end use items. Since AM is relatively new area of manufacturing processes, various processes are being developed and analyzed for their performance (mainly speed and accuracy). This paper deals with the design of a new benchmark part to analyze the flatness of parts produced on High Speed Sintering (HSS) which is a novel Additive Manufacturing process and is currently being developed at Loughborough University. The designed benchmark part comprised of various features such as cubes, holes, cylinders, spheres and cones on a flat base and the build material used for these parts was nylon 12 powder. Flatness and curvature of the base of these parts were measured using a coordinate measuring machine (CMM) and the results are discussed in relation to the operating parameters of the process.The result show changes in the flatness of part with the depth of part in the bed which is attributed to the thermal gradient within the build envelope during build.

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"ON-AXIS" LINEAR FOCUSED SPOT SCANNING MICROSTEREOLITHOGRAPHY SYSTEM: OPTOMECHATRONIC DESIGN, ANALYSIS AND DEVELOPMENT

Journal of Advanced Manufacturing Systems ◽

10.1142/s0219686713500030 ◽

2013 ◽

Vol 12 (01) ◽

pp. 43-68 ◽

Cited By ~ 14

Author(s):

PRASANNA GANDHI ◽

SUHAS DESHMUKH ◽

RAHUL RAMTEKKAR ◽

KIRAN BHOLE ◽

ALEM BARAKI

Keyword(s):

High Resolution ◽

System Integration ◽

High Speed ◽

Mechanical Design ◽

Three Dimensional ◽

Layer By Layer ◽

Optical Scanning ◽

High Production Rate ◽

High Production ◽

Scanning Mechanism

Microstereolithography (MSL) is technology of fabrication of three-dimensional (3D) components by using layer-by-layer photopolymerization. Typical design goals of MSL system are: small features, high resolution, high speed of fabrication, and large overall size of component. This paper focuses on design and development of such a system to meet these optomechatronic requirements. We first analyze various optical scanning schemes used for MSL systems along with the proposed scheme via optical simulations and experiments. Next, selection criteria for various subsystems are laid down and appropriate design decisions for the proposed system are made. Further, mechanical design of the scanning mechanism is carried out to meet requirements of high speed and resolution. Finally, system integration and investigation in process parameters is carried out and fabrication of large microcomponent with high resolution is demonstrated. The proposed system would be useful for fabrication of multiple/large microcomponents with high production rate in various applications.

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Compressive Sensing Based Three-Dimensional Imaging Method with Electro-Optic Modulation for Nonscanning Laser Radar

Symmetry ◽

10.3390/sym12050748 ◽

2020 ◽

Vol 12 (5) ◽

pp. 748

Author(s):

Yulong An ◽

Yanmei Zhang ◽

Haichao Guo ◽

Jing Wang

Keyword(s):

Compressive Sensing ◽

3D Imaging ◽

Low Cost ◽

Functional Model ◽

Three Dimensional ◽

Visible Spectrum ◽

Depth Map ◽

Imaging Method ◽

Practical Applications ◽

Electro Optic

Low-cost Laser Detection and Ranging (LiDAR) is crucial to three-dimensional (3D) imaging in applications such as remote sensing, target detection, and machine vision. In conventional nonscanning time-of-flight (TOF) LiDAR, the intensity map is obtained by a detector array and the depth map is measured in the time domain which requires costly sensors and short laser pulses. To overcome such limitations, this paper presents a nonscanning 3D laser imaging method that combines compressive sensing (CS) techniques and electro-optic modulation. In this novel scheme, electro-optic modulation is applied to map the range information into the intensity of echo pulses symmetrically and the measurements of pattern projection with symmetrical structure are received by the low bandwidth detector. The 3D imaging can be extracted from two gain modulated images that are recovered by solving underdetermined inverse problems. An integrated regularization model is proposed for the recovery problems and the minimization functional model is solved by a proposed algorithm applying the alternating direction method of multiplier (ADMM) technique. The simulation results on various subrates for 3D imaging indicate that our proposed method is feasible and achieves performance improvement over conventional methods in systems with hardware limitations. This novel method will be highly valuable for practical applications with advantages of low cost and flexible structure at wavelengths beyond visible spectrum.

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A Microwave Three-Dimensional Imaging Method Based on Optimal Wave Spectrum Reconstruction

Sensors ◽

10.3390/s20247306 ◽

2020 ◽

Vol 20 (24) ◽

pp. 7306

Author(s):

Yan Zhang ◽

Baoping Wang ◽

Yang Fang ◽

Zuxun Song

Keyword(s):

3D Imaging ◽

Imaging System ◽

Wave Spectrum ◽

Sampling Rate ◽

Three Dimensional ◽

Imaging Method ◽

Data Sampling ◽

Spectrum Reconstruction ◽

Memory Space ◽

Target Wave

Limited by the Shannon–Nyquist sampling law, the number of antenna elements and echo signal data of the traditional microwave three-dimensional (3D) imaging system are extremely high. Compressed sensing imaging methods based on sparse representation of target scene can reduce the data sampling rate, but the dictionary matrix of these methods takes a lot of memory, and the imaging has poor quality for continuously distributed targets. For the above problems, a microwave 3D imaging method based on optimal wave spectrum reconstruction and optimization with target reflectance gradient is proposed in this paper. Based on the analysis of the spatial distribution characteristics of the target echo in the frequency domain, this method constructs an orthogonal projection reconstruction model for the wavefront to realize the optimal reconstruction of the target wave spectrum. Then, the inverse Fourier transform of the optimal target wave spectrum is optimized according to the law of the target reflectance gradient distribution. The proposed method has the advantages of less memory space and less computation time. What is more, the method has a better imaging quality for the continuously distributed target. The computer simulation experiment and microwave anechoic chamber measurement experiment verify the effectiveness of the proposed method.

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A Novel 3D Imaging Method for Airborne Downward-Looking Sparse Array SAR Based on Special Squint Model

International Journal of Antennas and Propagation ◽

10.1155/2014/982014 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Xiaozhen Ren ◽

Yao Qin ◽

Lihong Qiao

Keyword(s):

3D Imaging ◽

Three Dimensional ◽

Imaging Method ◽

Computationally Efficient ◽

Theory Analysis ◽

Imaging Geometry ◽

Range Resolution ◽

Sparse Array ◽

Resolution Imaging ◽

Cross Track

Three-dimensional (3D) imaging technology based on antenna array is one of the most important 3D synthetic aperture radar (SAR) high resolution imaging modes. In this paper, a novel 3D imaging method is proposed for airborne down-looking sparse array SAR based on the imaging geometry and the characteristic of echo signal. The key point of the proposed algorithm is the introduction of a special squint model in cross track processing to obtain accurate focusing. In this special squint model, point targets with different cross track positions have different squint angles at the same range resolution cell, which is different from the conventional squint SAR. However, after theory analysis and formulation deduction, the imaging procedure can be processed with the uniform reference function, and the phase compensation factors and algorithm realization procedure are demonstrated in detail. As the method requires only Fourier transform and multiplications and thus avoids interpolations, it is computationally efficient. Simulations with point scatterers are used to validate the method.

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High-Speed, High-Resolution 3D Imaging Using Projector Defocusing

Depth Map and 3D Imaging Applications ◽

10.4018/978-1-61350-326-3.ch007 ◽

2011 ◽

pp. 121-140

Author(s):

Song Zhang ◽

Yuanzheng Gong

Keyword(s):

High Speed ◽

3D Imaging ◽

Imaging Techniques ◽

Three Dimensional ◽

Projection System ◽

Digital Fringe Projection ◽

System Nonlinearity ◽

Projection Techniques ◽

Fringe Patterns ◽

3D Scene

With the advance of software and hardware, three-dimensional (3D) scene digitization becomes increasingly important. Over the years, numerous 3D imaging techniques have been developed. Among these techniques, the methods based on analyzing sinusoidal structured (fringe) patterns stand out due to their achievable speed and resolution. With the development of digital video display technologies, digital fringe projection techniques emerge as a mainstream for 3D imaging. However, developing such a system is not easy especially when an off-the-shelf projector is used. The major challenging problems are: (1) the projection system nonlinearity; (2) the precise synchronization requirement; and (3) the projection system speed limit. This chapter will present an alternative route for 3D imaging while reducing these problems. The fundamentals of the proposed technique will be introduced, the analytical and experimental results will be shown, and its advantages and limitations will be addressed.

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High Speed Micro Holographic PIV Measurements of Microorganisms

Volume 10: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A, B, and C ◽

10.1115/imece2008-69272 ◽

2008 ◽

Author(s):

M. Zarzecki ◽

F. J. Diez

Keyword(s):

Velocity Field ◽

High Speed ◽

Fourier Transforms ◽

Three Dimensional ◽

Three Dimensions ◽

Imaging Method ◽

Time Resolved ◽

Feeding Methods ◽

Holographic Particle Image Velocimetry ◽

Three Components

Holographic particle image velocimetry (PIV) is a novel application of holography that allows for tracking of small particle sized objects in a small volume. Whereas regular PIV allows for the two in-plane components of the velocity field to be measured, and stereoscopic PIV allows for the three-components of the velocity field to be measured in a thin plane, holographic PIV allows for the three-components of the velocity to be measured for each individual particle present in the measuring volume, thus allowing to fully resolve fluid flows that are inherently 3D in nature. There are many examples of three dimensional flows in nature including turbulence flows, but another very interesting application very well suited for this technique involves tracking living microorganisms in order to study their motion and their means of propulsion. As part of this research a micro organism was tracked in three dimensions using a high speed microscopic holographic imaging method. The ability to track organisms in 3D allows better understanding and characterizing of their behavior including their propulsion methods, their feeding methods and their interaction with each other. The time resolved holograms were reconstructed in Matlab using Fast Fourier Transforms. A laser pointer was used as a source of coherent light, and a high speed PIV camera (Photron APX Ultima) was used to capture the images. A beam expander was used to increase the diameter of the laser beam allowing for a larger tracking area. Results with this system will show the trajectories in 3D of microorganisms as well as the three components of the velocity field showing the interaction of the organisms with their environment.

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Projection Microfabrication of Three-Dimensional Scaffolds for Tissue Engineering

Journal of Manufacturing Science and Engineering ◽

10.1115/1.2823079 ◽

2008 ◽

Vol 130 (2) ◽

Cited By ~ 69

Author(s):

Li-Hsin Han ◽

Gazell Mapili ◽

Shaochen Chen ◽

Krishnendu Roy

Keyword(s):

Tissue Engineering ◽

Uv Light ◽

Three Dimensional ◽

Layer By Layer ◽

Poly Ethylene Glycol ◽

Glycol Diacrylate ◽

Cellular Attachment ◽

Poly Ethylene ◽

Feature Resolution ◽

Graphic Software

This article presents a micromanufacturing method for direct projection printing of three-dimensional scaffolds for applications in the field of tissue engineering by using a digital micromirror-array device (DMD) in a layer-by-layer process. Multilayered scaffolds are microfabricated using curable materials through an ultraviolet (UV) photopolymerization process. The prepatterned UV light is projected onto the photocurable polymer solution by creating the “photomask” design with a graphic software. Poly(ethylene glycol) diacrylate is mixed with a small amount of dye (0.3wt%) to enhance the fabrication resolution of the scaffold. The DMD fabrication system is equipped with a purging mechanism to prevent the accumulation of oligomer, which could interfere with the feature resolution of previously polymerized layers. The surfaces of the predesigned multilayered scaffold are covalently conjugated with fibronectin for efficient cellular attachment. Our results show that murine marrow-derived progenitor cells successfully attached to fibronectin-modified scaffolds.

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