The Experts below are selected from a list of 67830 Experts worldwide ranked by ideXlab platform
Ji-xin Cheng - One of the best experts on this subject based on the ideXlab platform.
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Stimulated Raman spectroscopic imaging by Microsecond delay-line tuning
Multiphoton Microscopy in the Biomedical Sciences XVII, 2017Co-Authors: Chien-sheng Liao, Kai-chih Huang, Weili Hong, Andy J. Chen, Caroline W. Karanja, Pu Wang, Gregory Eakins, Ji-xin ChengAbstract:Stimulated Raman scattering (SRS) microscopy is a promising technique for label-free imaging of living systems. We demonstrate Microsecond-scale SRS spectral imaging by tuning two spectrally focused pulses temporally through a resonant delay-line. Our platform acquired an SRS spectrum within 42 Microseconds and formed a spectral image composed of 40,000 pixels in real-time.
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Microsecond scale vibrational spectroscopic imaging by multiplex stimulated raman scattering microscopy
Light-Science & Applications, 2015Co-Authors: Chien-sheng Liao, Mikhail N Slipchenko, Ping Wang, Junjie Li, Robert Aaron Oglesbee, Ji-xin ChengAbstract:Vibrational spectroscopic imaging on a Microsecond time scale has been realized using multiplex Raman microscopy. Real-time vibrational spectroscopic imaging holds out the promise of enabling cellular processes to be monitored without labeling, but this has been difficult to achieve because of the long acquisition times needed. Now, researchers at Purdue University in the USA have realized vibrational spectroscopic imaging by parallel detection of a spectrally dispersed stimulated Raman signal. Using a homemade system, they acquired Raman spectra in 32 Microseconds with a detection sensitivity that is nearly shot-noise limited. The scientists illustrate the potential of the technique by using it to obtain compositional maps of lipid droplets in living single cells, observe intracellular retinoid metabolism, and discriminate between fat droplets and protein-rich organelles in a nematode.
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Microsecond scale vibrational spectroscopic imaging by multiplex stimulated Raman scattering microscopy
Light: Science & Applications, 2015Co-Authors: Chien-sheng Liao, Mikhail N Slipchenko, Ping Wang, Junjie Li, Robert Aaron Oglesbee, Ji-xin ChengAbstract:Vibrational spectroscopic imaging on a Microsecond time scale has been realized using multiplex Raman microscopy. Real-time vibrational spectroscopic imaging holds out the promise of enabling cellular processes to be monitored without labeling, but this has been difficult to achieve because of the long acquisition times needed. Now, researchers at Purdue University in the USA have realized vibrational spectroscopic imaging by parallel detection of a spectrally dispersed stimulated Raman signal. Using a homemade system, they acquired Raman spectra in 32 Microseconds with a detection sensitivity that is nearly shot-noise limited. The scientists illustrate the potential of the technique by using it to obtain compositional maps of lipid droplets in living single cells, observe intracellular retinoid metabolism, and discriminate between fat droplets and protein-rich organelles in a nematode. Real-time vibrational spectroscopic imaging is desired for monitoring cellular states and cellular processes in a label-free manner. Raman spectroscopic imaging of highly dynamic systems is inhibited by relatively slow spectral acquisition on millisecond to second scale. Here, we report Microsecond scale vibrational spectroscopic imaging by lock-in free parallel detection of spectrally dispersed stimulated Raman scattering signal. Using a homebuilt tuned amplifier array, our method enables Raman spectral acquisition, within the window defined by the broadband pulse, at the speed of 32 µs and with close to shot-noise limited detection sensitivity. Incorporated with multivariate curve resolution analysis, our platform allows compositional mapping of lipid droplets in single live cells, observation of intracellular retinoid metabolism, discrimination of fat droplets from protein-rich organelles in Caenorhabditis elegans , spectral detection of fast flowing tumor cells and monitoring drug diffusion through skin tissue in vivo . The reported technique opens new opportunities for compositional analysis of cellular compartment in a microscope setting and high-throughput spectral profiling of single cells in a flow cytometer setting.
Chien-sheng Liao - One of the best experts on this subject based on the ideXlab platform.
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Stimulated Raman spectroscopic imaging by Microsecond delay-line tuning
Multiphoton Microscopy in the Biomedical Sciences XVII, 2017Co-Authors: Chien-sheng Liao, Kai-chih Huang, Weili Hong, Andy J. Chen, Caroline W. Karanja, Pu Wang, Gregory Eakins, Ji-xin ChengAbstract:Stimulated Raman scattering (SRS) microscopy is a promising technique for label-free imaging of living systems. We demonstrate Microsecond-scale SRS spectral imaging by tuning two spectrally focused pulses temporally through a resonant delay-line. Our platform acquired an SRS spectrum within 42 Microseconds and formed a spectral image composed of 40,000 pixels in real-time.
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Microsecond scale vibrational spectroscopic imaging by multiplex stimulated raman scattering microscopy
Light-Science & Applications, 2015Co-Authors: Chien-sheng Liao, Mikhail N Slipchenko, Ping Wang, Junjie Li, Robert Aaron Oglesbee, Ji-xin ChengAbstract:Vibrational spectroscopic imaging on a Microsecond time scale has been realized using multiplex Raman microscopy. Real-time vibrational spectroscopic imaging holds out the promise of enabling cellular processes to be monitored without labeling, but this has been difficult to achieve because of the long acquisition times needed. Now, researchers at Purdue University in the USA have realized vibrational spectroscopic imaging by parallel detection of a spectrally dispersed stimulated Raman signal. Using a homemade system, they acquired Raman spectra in 32 Microseconds with a detection sensitivity that is nearly shot-noise limited. The scientists illustrate the potential of the technique by using it to obtain compositional maps of lipid droplets in living single cells, observe intracellular retinoid metabolism, and discriminate between fat droplets and protein-rich organelles in a nematode.
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Microsecond scale vibrational spectroscopic imaging by multiplex stimulated Raman scattering microscopy
Light: Science & Applications, 2015Co-Authors: Chien-sheng Liao, Mikhail N Slipchenko, Ping Wang, Junjie Li, Robert Aaron Oglesbee, Ji-xin ChengAbstract:Vibrational spectroscopic imaging on a Microsecond time scale has been realized using multiplex Raman microscopy. Real-time vibrational spectroscopic imaging holds out the promise of enabling cellular processes to be monitored without labeling, but this has been difficult to achieve because of the long acquisition times needed. Now, researchers at Purdue University in the USA have realized vibrational spectroscopic imaging by parallel detection of a spectrally dispersed stimulated Raman signal. Using a homemade system, they acquired Raman spectra in 32 Microseconds with a detection sensitivity that is nearly shot-noise limited. The scientists illustrate the potential of the technique by using it to obtain compositional maps of lipid droplets in living single cells, observe intracellular retinoid metabolism, and discriminate between fat droplets and protein-rich organelles in a nematode. Real-time vibrational spectroscopic imaging is desired for monitoring cellular states and cellular processes in a label-free manner. Raman spectroscopic imaging of highly dynamic systems is inhibited by relatively slow spectral acquisition on millisecond to second scale. Here, we report Microsecond scale vibrational spectroscopic imaging by lock-in free parallel detection of spectrally dispersed stimulated Raman scattering signal. Using a homebuilt tuned amplifier array, our method enables Raman spectral acquisition, within the window defined by the broadband pulse, at the speed of 32 µs and with close to shot-noise limited detection sensitivity. Incorporated with multivariate curve resolution analysis, our platform allows compositional mapping of lipid droplets in single live cells, observation of intracellular retinoid metabolism, discrimination of fat droplets from protein-rich organelles in Caenorhabditis elegans , spectral detection of fast flowing tumor cells and monitoring drug diffusion through skin tissue in vivo . The reported technique opens new opportunities for compositional analysis of cellular compartment in a microscope setting and high-throughput spectral profiling of single cells in a flow cytometer setting.
Prasant Mohapatra - One of the best experts on this subject based on the ideXlab platform.
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soft tdmac a software based 802 11 overlay tdma mac with Microsecond synchronization
IEEE Transactions on Mobile Computing, 2012Co-Authors: Petar Djukic, Prasant MohapatraAbstract:We implement a new software-based multihop TDMA MAC protocol (Soft-TDMAC) with Microsecond synchronization using a novel system interface for development of 802.11 overlay TDMA MAC protocols (SySI-MAC). SySI-MAC provides a kernel independent message-based interface for scheduling transmissions and sending and receiving 802.11 packets. The key feature of SySI-MAC is that it provides near deterministic timers and transmission times, which allows for implementation of highly synchronized TDMA MAC protocols. Building on SySI-MAC's predictable transmission times, we implement Soft-TDMAC, a software-based 802.11 overlay multihop TDMA MAC protocol. Soft-TDMAC has a synchronization mechanism, which synchronizes all pairs of network clocks to within Microseconds of each other. Building on pairwise synchronization, Soft-TDMAC achieves tight network-wide synchronization. With network-wide synchronization independent of data transmissions, Soft-TDMAC can schedule arbitrary TDMA transmission patterns. For example, Soft-TDMAC allows schedules that decrease end-to-end delay and take end-to-end rate demands into account. We summarize hundreds of hours of testing Soft-TDMAC on a multihop testbed, showing the synchronization capabilities of the protocol and the benefits of flexible scheduling.
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soft tdmac a software tdma based mac over commodity 802 11 hardware
International Conference on Computer Communications, 2009Co-Authors: Petar Djukic, Prasant MohapatraAbstract:We design and implement Soft-TDMAC, a software Time Division Multiple Access (TDMA) based MAC protocol, running over commodity 802.11 hardware. Soft-TDMAC has a synchronization mechanism, which synchronizes all pairs of network clocks to within Microseconds of each other. Building on pairwise synchronization, Soft-TDMAC achieves network wide synchronization. With, out-of-band, network wide synchronization Soft-TDMAC can schedule arbitrary TDMA transmission patterns. We summarize hundreds of hours of testing Soft-TDMAC on a multi-hop testbed. Our experimental results show that Soft-TDMAC synchronizes multi-hop networks to within a few Microsecond sized TDMA slots. Soft-TDMAC can schedule transmissions to take end-to-end demands into account and in a way that decreases end-to-end delay. With no collisions, under good channel conditions, TCP achieves almost the full wireless channel bandwidth.
Vahid Sandoghdar - One of the best experts on this subject based on the ideXlab platform.
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interferometric scattering microscopy reveals Microsecond nanoscopic protein motion on a live cell membrane
Nature Photonics, 2019Co-Authors: Richard W. Taylor, Reza Gholami Mahmoodabadi, Verena Rauschenberger, Andreas Gießl, Alexandra Schambony, Vahid SandoghdarAbstract:Many of the biological functions of a cell are dictated by the intricate motion of proteins within its membrane over a spatial range of nanometres to tens of micrometres and time intervals of Microseconds to minutes. This rich parameter space is not accessible by fluorescence microscopy, but it is within reach of interferometric scattering (iSCAT) particle tracking. However, as iSCAT is sensitive even to single unlabelled proteins, it is often accompanied by a large speckle-like background, which poses a substantial challenge for its application to cellular imaging. Here, we employ a new image processing approach to overcome this difficulty and demonstrate tracking of transmembrane epidermal growth factor receptors with nanometre precision in all three dimensions at up to Microsecond speeds and for durations of tens of minutes. We provide examples of nanoscale motion and confinement in ubiquitous processes such as diffusion in the plasma membrane, transport on filopodia and rotational motion during endocytosis.
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interferometric scattering microscopy reveals Microsecond nanoscopic protein motion on a live cell membrane
Nature Photonics, 2019Co-Authors: Richard W. Taylor, Reza Gholami Mahmoodabadi, Verena Rauschenberger, Andreas Gießl, Alexandra Schambony, Vahid SandoghdarAbstract:Many of the biological functions of a cell are dictated by the intricate motion of proteins within its membrane over a spatial range of nanometres to tens of micrometres and time intervals of Microseconds to minutes. This rich parameter space is not accessible by fluorescence microscopy, but it is within reach of interferometric scattering (iSCAT) particle tracking. However, as iSCAT is sensitive even to single unlabelled proteins, it is often accompanied by a large speckle-like background, which poses a substantial challenge for its application to cellular imaging. Here, we employ a new image processing approach to overcome this difficulty and demonstrate tracking of transmembrane epidermal growth factor receptors with nanometre precision in all three dimensions at up to Microsecond speeds and for durations of tens of minutes. We provide examples of nanoscale motion and confinement in ubiquitous processes such as diffusion in the plasma membrane, transport on filopodia and rotational motion during endocytosis. Interferometric scattering microscopy is employed to track proteins in live cell membranes, demonstrating tracking of transmembrane epidermal growth factor receptors with nanometre precision in all three dimensions at up to Microsecond speeds and for durations of tens of minutes.
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interferometric scattering microscopy reveals Microsecond nanoscopic protein motion on a live cell membrane
bioRxiv, 2018Co-Authors: Richard W. Taylor, Reza Gholami Mahmoodabadi, Verena Rauschenberger, Andreas Gießl, Alexandra Schambony, Vahid SandoghdarAbstract:Much of the biological functions of a cell are dictated by the intricate motion of proteins within its membrane over a spatial range of nanometers to tens of micrometers and time intervals of Microseconds to minutes. While this rich parameter space is not accessible to fluorescence microscopy, it can be within reach of interferometric scattering (iSCAT) particle tracking. Being sensitive even to single unlabeled proteins, however, iSCAT is easily accompanied by a large speckle-like background, which poses a substantial challenge for its application to cellular imaging. Here, we show that these difficulties can be overcome and demonstrate tracking of transmembrane epidermal growth factor receptors (EGFR) with nanometer precision in all three dimensions at up to Microsecond speeds and tens of minutes duration. We provide unprecedented examples of nanoscale motion and confinement in ubiquitous processes such as diffusion in the plasma membrane, transport on filopodia, and endocytosis.
Mikhail N Slipchenko - One of the best experts on this subject based on the ideXlab platform.
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Microsecond scale vibrational spectroscopic imaging by multiplex stimulated raman scattering microscopy
Light-Science & Applications, 2015Co-Authors: Chien-sheng Liao, Mikhail N Slipchenko, Ping Wang, Junjie Li, Robert Aaron Oglesbee, Ji-xin ChengAbstract:Vibrational spectroscopic imaging on a Microsecond time scale has been realized using multiplex Raman microscopy. Real-time vibrational spectroscopic imaging holds out the promise of enabling cellular processes to be monitored without labeling, but this has been difficult to achieve because of the long acquisition times needed. Now, researchers at Purdue University in the USA have realized vibrational spectroscopic imaging by parallel detection of a spectrally dispersed stimulated Raman signal. Using a homemade system, they acquired Raman spectra in 32 Microseconds with a detection sensitivity that is nearly shot-noise limited. The scientists illustrate the potential of the technique by using it to obtain compositional maps of lipid droplets in living single cells, observe intracellular retinoid metabolism, and discriminate between fat droplets and protein-rich organelles in a nematode.
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Microsecond scale vibrational spectroscopic imaging by multiplex stimulated Raman scattering microscopy
Light: Science & Applications, 2015Co-Authors: Chien-sheng Liao, Mikhail N Slipchenko, Ping Wang, Junjie Li, Robert Aaron Oglesbee, Ji-xin ChengAbstract:Vibrational spectroscopic imaging on a Microsecond time scale has been realized using multiplex Raman microscopy. Real-time vibrational spectroscopic imaging holds out the promise of enabling cellular processes to be monitored without labeling, but this has been difficult to achieve because of the long acquisition times needed. Now, researchers at Purdue University in the USA have realized vibrational spectroscopic imaging by parallel detection of a spectrally dispersed stimulated Raman signal. Using a homemade system, they acquired Raman spectra in 32 Microseconds with a detection sensitivity that is nearly shot-noise limited. The scientists illustrate the potential of the technique by using it to obtain compositional maps of lipid droplets in living single cells, observe intracellular retinoid metabolism, and discriminate between fat droplets and protein-rich organelles in a nematode. Real-time vibrational spectroscopic imaging is desired for monitoring cellular states and cellular processes in a label-free manner. Raman spectroscopic imaging of highly dynamic systems is inhibited by relatively slow spectral acquisition on millisecond to second scale. Here, we report Microsecond scale vibrational spectroscopic imaging by lock-in free parallel detection of spectrally dispersed stimulated Raman scattering signal. Using a homebuilt tuned amplifier array, our method enables Raman spectral acquisition, within the window defined by the broadband pulse, at the speed of 32 µs and with close to shot-noise limited detection sensitivity. Incorporated with multivariate curve resolution analysis, our platform allows compositional mapping of lipid droplets in single live cells, observation of intracellular retinoid metabolism, discrimination of fat droplets from protein-rich organelles in Caenorhabditis elegans , spectral detection of fast flowing tumor cells and monitoring drug diffusion through skin tissue in vivo . The reported technique opens new opportunities for compositional analysis of cellular compartment in a microscope setting and high-throughput spectral profiling of single cells in a flow cytometer setting.
