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  • 廖仲麒 博士
    Nature Communications, 9, 2023 (2018).
    Distal appendages (DAPs) are nanoscale, pinwheel-like structures protruding from the distal end of the centriole that mediate membrane docking during ciliogenesis, marking the cilia base around the ciliary gate. Here we determine a super-resolved multiplex of 16 centriole-distal-end components. Surprisingly, rather than pinwheels, intact DAPs exhibit a cone-shaped architecture with components filling the space between each pinwheel blade, a new structural element we term the distal appendage matrix (DAM). Specifically, CEP83, CEP89, SCLT1, and CEP164 form the backbone of pinwheel blades, with CEP83 confined at the root and CEP164 extending to the tip near the membrane-docking site. By contrast, FBF1 marks the distal end of the DAM near the ciliary membrane. Strikingly, unlike CEP164, which is essential for ciliogenesis, FBF1 is required for ciliary ...
  • 林志民 博士
    Angew. Chem. Int. Ed. (DOI: 10.1002/anie.201900711, 2019).
    Recent reports [Jara‐Toro et al., Angew. Chem. Int. Ed. 2017, 56, 2166 and PCCP 2018, 20, 27885] suggest that the rate coefficient of OH reactions with alcohols would increase by up to two times in going from dry to high humidity. This finding would have an impact on the budget of alcohols in the atmosphere and it may explain differences in measured and modeled methanol concentrations. The results were based on a relative technique carried out in a small Teflon bag, which might suffer from wall reactions. The effect was reinvestigated using a direct fluorescence probe of OH radicals, and no catalytic effect of H2O could be found. Experiments in a Teflon bag were also carried out, but the results of Jara‐Toro et al. were not reproducible. Further theoretical calculations show that the water‐mediated reactions have negligible rates compared to  ...
  • 陳應誠 博士
    Phys. Rev. Lett. 120, 183602 (2018).
    Quantum memory is a device that can store and then retrieve a quantum state on demand. It is an important building block in long-distance quantum communication. To outperform the direct transmission of photons with quantum repeaters, it is crucial to develop quantum memories with high fidelity, high efficiency and a long storage time. We achieved a storage efficiency of 92.0 % for a coherent optical memory based on the electromagnetically induced transparency scheme in optically dense cold atomic media. We also obtain a useful time-bandwidth product of 1200, considering only storage where the retrieval efficiency remains above 50 %. Both are the best record to date in all kinds of the schemes for the realization of optical memory. Our work significantly advances the pursuit of a high-performance optical memory and should have important applications ...
  • 林育如 博士
    Physical Review Letters 121, 250401 (2018).
    We realize synthetic azimuthal gauge potentials for Bose-Einstein condensates along with spin-orbital-angular-momentum coupling. This is achieved by engineering atom-light interactions. We characterize the spin textures of the atoms and exploit the azimuthal gauge potential to demonstrate the Hess-Fairbank effect, the analogue of Meissner effect in superconductors. Our demonstration serves as a paradigm to create topological excitations by tailoring atom-light interactions where both types of SO(3) vortices in the     manifold, coreless vortices and polar-core vortices, are created in our experiment. The gauge field in the stationary Hamiltonian opens a path to investigating rotation properties of atomic superfluids under thermal equilibrium.
  • 陳貴賢 博士
    NATURE COMMUNICATIONS (DOI: 10.1038/s41467-017-02547-4, 2018)
    Carbon-doped SnS2 (SnS2-C) metal dichalcogenide nanostructure has been synthesized using a hydrothermal technique, which exhibits a highly active and selective photocatalytic conversion of CO2 to hydrocarbons under visible-light, attaining a photochemical quantum efficiency of above 0.7%. The SnS2 -C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO2 reduction under visible light.
  • 高橋開人 博士
    Physical Chemistry Chemical Physics, 20, 20217-20227 (2018).
    Criegee intermediates (CIs), formed in the reactions of unsaturated hydrocarbons with ozone, are very reactive carbonyl oxides and have recently been suggested as important oxidants in the atmosphere. In this work, we studied the substituent effect on the water monomer and dimer reaction with CIs which include up to three carbon atoms at the QCISD(T)/CBS//B3LYP/6-311+G(2d,2p) level. Our calculation showed that for saturated CIs with a hydrogen atom on the same side as the terminal oxygen atom, the reaction with water vapor would likely dominate the removal processes of these CIs in the atmosphere. On the other hand, for unsaturated CIs, the reactivity toward water vapor decreases compared to the saturated species allowing them to survive in humid atmospheric environments. We also evaluated the kinetic isotope effect in the reaction between CI and w ...
  • 劉國平 博士
    Nature Chemistry, 9, 1175-1180 (2017).
    The transition state, which gates and modulates the reactive flux, serves as the central concept in our understanding of activated reactions. The barrier height of the transition state can be estimated from the activation energy taken from thermal kinetics data or from the energetic threshold in the measured excitation function (the dependence of reaction cross sections on initial collision energies). However, another critical and equally important property, the angle-dependent barrier to reaction, has not yet been amenable to experimental determination until now. Here, using the benchmark reaction of Cl + CHD3(v1 = 1) as an example, we show how to map this anisotropic property of the transition state as a function of collision energy from the preferred reactant bond alignment of the backward-scattered products ‒ the imprints of small  ...
  • 張煥正 博士
    Anal. Chem. 90, 1566–1571 (2018).
    Containing an ensemble of nitrogen-vacancy centers in crystal matrices, fluorescent nanodiamonds (FNDs) are a new type of photostable markers that have found wide applications in light microscopy.  The nanomaterial also has a dense carbon core, making it visible to electron microscopy.  Here, we show that FNDs encapsulated in biotinylated lipids (bLs) are useful for sub-diffraction imaging of antigens on cell surface with correlative light-electron microscopy (CLEM).  The lipid encapsulation enables not only good dispersion of the particles in biological buffers but also high specific labeling of live cells.  By employing the bL-encapsulated FNDs to target CD44 on HeLa cell surface through biotin-mediated immunostaining, we obtained the spatial distribution of these antigens by CLEM with a localization accuracy of ~50 nm in rout ...
  • 謝佳龍 博士
    Nanoscale 11, 568-577 (2019).
    Nanoparticles have been used extensively in biology-related research and many applications require direct visualization of individual nanoparticles under optical microscopy. For long-term and high-speed measurements, scattering-based microscopy is a unique technique because of the stable and indefinite scattering signal. In scattering-based single-particle measurements, large nanoparticles are usually needed in order to generate sufficient signal for detection. However, larger nanoparticle introduces greater mass loading, experiences stronger steric hindrance, and is more prone to crosslinking. In this work, we demonstrate coherent brightfield (COBRI) microscopy with enhanced contrast and show its capability of direct visualization of very small nanoparticles in scattering at high speed. The COBRI microscopy allows us to visualize and track single  ...
  • 曾文碧 博士
    Physical Chemistry Chemical Physics, 21, 9665-9671 (2019).
    The resonance-enhanced multiphoton ionization (REMPI) of a mixed sandwich complex has been achieved for the first time when exciting (η7-C7H7)(η5-C5H5)Cr via the Rydberg 4pz state. The REMPI spectrum is indicative of unexpectedly small changes of the sandwich geometry on excitation. Time- dependent DFT calculations reveal fine effects of the ligand nature on the molecular and electronic structure variations accompanying electronic excitation. Different trends are predicted for the sandwich geometry transformations in the mixed sandwich complex and its symmetric isomer, (η6-C6H6)2Cr, both on Rydberg excitation and ionization.
  • 楊大衍 博士
    Scientific Reports 7, 39792 (2017).
    Proteins are of interest in nano-bio electronic devices due to their versatile structures, exquisite functionality and specificity. However, quantum transport measurements produce conflicting results due to technical limitations whereby it is difficult to precisely determine molecular orientation, the nature of the moieties, the presence of the surroundings and the temperature; in such circumstances a better understanding of the protein electron transfer (ET) pathway and the mechanism remains a considerable challenge. Here, we report an approach to mechanically drive polypeptide flip-flop motion to achieve a logic gate with ON and OFF states during protein ET. We have calculated the transmission spectra of the peptide-based molecular junctions and observed the hallmarks of electrical current and conductance. The results indicate that peptide ET fol ...
  • 余慈顏 博士
    Scientific Reports, 8, 13501 (2018).
    Incorporating membrane proteins into membrane mimicking systems is an essential process for biophysical studies and structure determination. Monodisperse lipid nanodiscs have been found to be a suitable tool, as they provide a near-native lipid bilayer environment. Recently, a covalently circularized nanodisc (cND) assembled with a membrane scaffold protein (MSP) in circular form, instead of conventional linear form, has emerged. Covalently circularized nanodiscs have been shown to have improved stability, however the optimal strategies for the incorporation of membrane proteins, as well as the physicochemical properties of the membrane protein embedded in the cND, have not been studied. Bacteriorhodopsin (bR) is a seven-transmembrane helix (7TM) membrane protein, and it forms a two dimensional crystal consisting of trimeric bR on the purple membra ...
  • 謝佳龍 博士
    ACS Nano, Just Accepted (2019).
    Single-molecule tracking is a powerful method to study molecular dynamics in living systems including biological membranes. High-resolution single-molecule tracking requires a bright and stable signal, which has typically been facilitated by nanoparticles due to their superb optical properties. However, there are concerns about using a nanoparticle to label a single molecule because of its relatively large size and the possibility of crosslinking multiple target molecules, both of which could affect the original molecular dynamics. In this work, using various labeling schemes, we investigate the effects of the use of nanoparticles to measure the diffusion of single membrane molecules. By conjugating a low density of streptavidin (sAv) to gold nanoparticles (AuNPs) of different sizes (10, 15, 20, 30, and 40 nm), we isolate and quantify the effect of ...
  • 許良彥 博士
    Journal of Chemical Physics 151, 014105 (2019).
    We study a molecular emitter above a silver surface in the framework of macroscopic quantum electrodynamics and explore the population dynamics including non-Markovian effects. The theory we present is general for molecular fluorescence in the presence of dielectrics with any space-dependent, frequency-dependent, or complex dielectric functions. Furthermore, the proposed theory allows us to calculate the memory kernel of polaritons using computational electrodynamics packages. In the limit of a high vibration frequency, the different strengths of exciton-polariton couplings lead to distinct characteristics in the population dynamics, e.g., Franck-Condon-Rabi oscillation. (The frequency of Rabi oscillation is dependent on the Franck-Condon factor.) Additionally, in a specific condition, we derive a parameter-free formula that can be used to estimate ...