The Experts below are selected from a list of 193974 Experts worldwide ranked by ideXlab platform
A M Biradar - One of the best experts on this subject based on the ideXlab platform.
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bismuth ferrite nanoparticles for modulation of helical structure at the interface of ferroelectric liquid crystal and substrate
Journal of Applied Physics, 2020Co-Authors: Sidra Khan, Amit Choudhary, Jai Prakash, Shikha Chauhan, A M BiradarAbstract:We report the impact of dispersion of bismuth ferrite nanoparticles (BF-NPs) on the helical structure of a ferroelectric liquid crystal (FLC) in two ways: on the surface and into the bulk of FLC. The optical textural observations of the FLC Sample Cell with BF-NPs on the surface of the substrate show a remarkable change of three different domains having varied molecular orientation in comparison to pure and bulk dispersed FLC, where only two types of domains of different molecular orientations are observed at room temperature. These observations have confirmed distinct molecular dynamics in all the Samples. The dispersion of BF-NPs in the bulk of FLC causes a slight shift in a chiral smectic C* (SmC*)–chiral smectic A* (SmA*) phase transition toward a higher temperature. The Goldstone mode (GM) relaxation frequency of the bulk dispersed Sample is shifted toward the higher frequency as the temperature is increased and finally is suppressed once the transition from the SmC* phase to the SmA* phase occurs. A...
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memory effect in cadmium telluride quantum dots doped ferroelectric liquid crystals
Applied Physics Letters, 2010Co-Authors: Ajay Kumar, Jai Prakash, Mohd Taukeer Khan, Sangeeta Dhawan, A M BiradarAbstract:A pronounced memory effect has been observed in cadmium telluride quantum dots (CdTe-QDs) doped ferroelectric liquid crystals (FLCs) by using dielectric and electro-optical methods. The memory effect has been attributed to the charge storage on the CdTe-QDs upon the application of dc bias across the Sample Cell. The FLC molecules remain in the switched state in vicinity of the charge stored on QDs even after removal of bias. It has been observed that the memory effect depends on doping concentrations of CdTe-QDs and the FLC material used.
Junjie Zhu - One of the best experts on this subject based on the ideXlab platform.
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massively parallel digital transcriptional profiling of single Cells
Nature Communications, 2017Co-Authors: Grace X Y Zheng, Jessica M Terry, Phillip Belgrader, Paul Ryvkin, Zachary Bent, Ryan Wilson, Solongo B Ziraldo, Tobias Daniel Wheeler, Geoffrey P Mcdermott, Junjie ZhuAbstract:Characterizing the transcriptome of individual Cells is fundamental to understanding complex biological systems. We describe a droplet-based system that enables 3′ mRNA counting of tens of thousands of single Cells per Sample. Cell encapsulation, of up to 8 Samples at a time, takes place in ∼6 min, with ∼50% Cell capture efficiency. To demonstrate the system’s technical performance, we collected transcriptome data from ∼250k single Cells across 29 Samples. We validated the sensitivity of the system and its ability to detect rare populations using Cell lines and synthetic RNAs. We profiled 68k peripheral blood mononuclear Cells to demonstrate the system’s ability to characterize large immune populations. Finally, we used sequence variation in the transcriptome data to determine host and donor chimerism at single-Cell resolution from bone marrow mononuclear Cells isolated from transplant patients. Single-Cell gene expression analysis is challenging. This work describes a new droplet-based single Cell RNA-seq platform capable of processing tens of thousands of Cells across 8 independent Samples in minutes, and demonstrates Cellular subtypes and host–donor chimerism in transplant patients.
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massively parallel digital transcriptional profiling of single Cells
bioRxiv, 2016Co-Authors: Grace X Y Zheng, Jessica M Terry, Phillip Belgrader, Paul Ryvkin, Zachary Bent, Ryan Wilson, Solongo B Ziraldo, Tobias Daniel Wheeler, Geoffrey P Mcdermott, Junjie ZhuAbstract:Characterizing the transcriptome of individual Cells is fundamental to understanding complex biological systems. We describe a droplet-based system that enables 3′ mRNA counting of up to tens of thousands of single Cells per Sample. Cell encapsulation in droplets takes place in ~6 minutes, with ~50% Cell capture efficiency, up to 8 Samples at a time. The speed and efficiency allow the processing of precious Samples while minimizing stress to Cells. To demonstrate the system′s technical performance and its applications, we collected transcriptome data from ~¼ million single Cells across 29 Samples. First, we validate the sensitivity of the system and its ability to detect rare populations using Cell lines and synthetic RNAs. Then, we profile 68k peripheral blood mononuclear Cells (PBMCs) to demonstrate the system′s ability to characterize large immune populations. Finally, we use sequence variation in the transcriptome data to determine host and donor chimerism at single Cell resolution in bone marrow mononuclear Cells (BMMCs) of transplant patients. This analysis enables characterization of the complex interplay between donor and host Cells and monitoring of treatment response. This high-throughput system is robust and enables characterization of diverse biological systems with single Cell mRNA analysis.
Lixing Zhou - One of the best experts on this subject based on the ideXlab platform.
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an adiabatic low temperature calorimeter for heat capacity measurement of small Samples
Journal of Thermal Analysis and Calorimetry, 1995Co-Authors: Zhicheng Tan, Guanyu Sun, Yi Sun, Anxue Yin, Wenbin Wang, Lixing ZhouAbstract:A small Sample adiabatic calorimeter for measuring heat capacities in the temperature range 60–350 K using the Nernst method has been constructed. The Sample Cell of the calorimeter is 6 cm3 in the internal volume, equipped with a miniature platinum thermometer and surrounded by two adiabatic shields. Two sets of 6-junction chromel-copel thermocouples were mounted between the Cell and the shields to indicate the temperature differences between them. The adiabatic conditions of the Cell were automatically controlled by two sets of temperature controller. A mechanical pump was used to pump out the vapour of liquid nitrogen in the cryostat to solidify N2 (1), and 60 K or even lower temperature was obtained. The performance of this apparatus was evaluated by heat capacity measurements on α-alumina. The deviations of experimental results from a smoothed curve lie within ±0.2%, while the inaccuracy is within ±0.5% compared with the recommended reference data in the wole temperature range.
R J D Miller - One of the best experts on this subject based on the ideXlab platform.
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ultrafast memory loss and energy redistribution in the hydrogen bond network of liquid h2o
Nature, 2005Co-Authors: M L Cowan, Jason R Dwyer, B D Bruner, Nils Huse, B Chugh, Erik T J Nibbering, T Elsaesser, R J D MillerAbstract:Water has many unique features that distinguish it from other liquids. A key to these properties is the dynamic network of hydrogen bonds linking the highly polar water molecules. Infrared spectroscopy of the hydroxyl (OH) stretching vibration is ideal for probing the dynamics and structure of this network, but technical limitations have meant that it has been necessary to use mixtures of isotopically substituted water and observe, for example, the deuteroxyl (OD) bond in normal water (H2O). Now by using an ultrathin Sample Cell, the behaviour of the hydrogen bond network structure has been studied in pure H2O. The results are surprising: water loses its ‘memory’ of structural correlations within 50 femtoseconds, an order of magnitude faster than seen previously. This favours rapid relaxation of elementary excitations, which may contribute to the stability of biological systems that strongly interact with surrounding water. Many of the unusual properties of liquid water are attributed to its unique structure, comprised of a random and fluctuating three-dimensional network of hydrogen bonds that link the highly polar water molecules1,2. One of the most direct probes of the dynamics of this network is the infrared spectrum of the OH stretching vibration3,4,5,6,7,8,9,10,11, which reflects the distribution of hydrogen-bonded structures and the intermolecular forces controlling the structural dynamics of the liquid. Indeed, water dynamics has been studied in detail5,6,7,8,9,10,11,12,13,14, most recently using multi-dimensional nonlinear infrared spectroscopy15,16 for acquiring structural and dynamical information on femtosecond timescales. But owing to technical difficulties, only OH stretching vibrations in D2O or OD vibrations in H2O could be monitored. Here we show that using a specially designed, ultrathin Sample Cell allows us to observe OH stretching vibrations in H2O. Under these fully resonant conditions, we observe hydrogen bond network dynamics more than one order of magnitude faster than seen in earlier studies that include an extremely fast sweep in the OH frequencies on a 50-fs timescale and an equally fast disappearance of the initial inhomogeneous distribution of sites. Our results highlight the efficiency of energy redistribution within the hydrogen-bonded network, and that liquid water essentially loses the memory of persistent correlations in its structure within 50 fs.
Jai Prakash - One of the best experts on this subject based on the ideXlab platform.
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bismuth ferrite nanoparticles for modulation of helical structure at the interface of ferroelectric liquid crystal and substrate
Journal of Applied Physics, 2020Co-Authors: Sidra Khan, Amit Choudhary, Jai Prakash, Shikha Chauhan, A M BiradarAbstract:We report the impact of dispersion of bismuth ferrite nanoparticles (BF-NPs) on the helical structure of a ferroelectric liquid crystal (FLC) in two ways: on the surface and into the bulk of FLC. The optical textural observations of the FLC Sample Cell with BF-NPs on the surface of the substrate show a remarkable change of three different domains having varied molecular orientation in comparison to pure and bulk dispersed FLC, where only two types of domains of different molecular orientations are observed at room temperature. These observations have confirmed distinct molecular dynamics in all the Samples. The dispersion of BF-NPs in the bulk of FLC causes a slight shift in a chiral smectic C* (SmC*)–chiral smectic A* (SmA*) phase transition toward a higher temperature. The Goldstone mode (GM) relaxation frequency of the bulk dispersed Sample is shifted toward the higher frequency as the temperature is increased and finally is suppressed once the transition from the SmC* phase to the SmA* phase occurs. A...
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memory effect in cadmium telluride quantum dots doped ferroelectric liquid crystals
Applied Physics Letters, 2010Co-Authors: Ajay Kumar, Jai Prakash, Mohd Taukeer Khan, Sangeeta Dhawan, A M BiradarAbstract:A pronounced memory effect has been observed in cadmium telluride quantum dots (CdTe-QDs) doped ferroelectric liquid crystals (FLCs) by using dielectric and electro-optical methods. The memory effect has been attributed to the charge storage on the CdTe-QDs upon the application of dc bias across the Sample Cell. The FLC molecules remain in the switched state in vicinity of the charge stored on QDs even after removal of bias. It has been observed that the memory effect depends on doping concentrations of CdTe-QDs and the FLC material used.
