High-dispersion coronagraphy (HDC) optimally combines high-contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway toward fully characterizing exoplanet atmospheres across a broad range of masses from giant gaseous planets down to Earth-like planets. In addition to determining the molecular composition of exoplanet atmospheres, HDC also enables Doppler mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as precise measurements of exoplanet rotational velocities. Here, we demonstrate an innovative concept for injecting the directly imaged planet light into a single-mode fiber, linking a high-contrast adaptively corrected coronagraph to a high-resolution spectrograph (diffraction-limited or not). Our laboratory demonstration includes three key milestones: close-to-theoretical injection efficiency, accurate pointing and tracking, and on-fiber coherent modulation and speckle nulling of spurious starlight signal coupling into the fiber. Using the extreme modal selectivity of single-mode fibers, we also demonstrated speckle suppression gains that outperform conventional image-based speckle nulling by at least two orders of magnitude.
[1] Harmonic analysis of 10 years of TOPEX/Poseidon (TP) along-track altimetry is performed to derive the semidiurnal, diurnal, long-period, and quarter-diurnal tides in the Bohai, Yellow, and East China Seas. The TP solutions are evaluated through intercomparison for crossover points and comparison with the ground truth, showing that the accuracy of TP solutions in the study area has achieved levels of 2-4 cm in amplitudes and 5°in phase lags for principal constituents (M 2 , S 2 , K 1 , O 1 , and S a ). The TP-derived S a amplitudes have a systematic bias of about À10% as compared with the ground truth, indicating the possible importance of loading effect of this constituent in the study area, which is generally not considered in geodetic surveys. The tidal harmonics from TP altimetry and at coastal and island stations are used to give a new set of empirical cotidal charts for principal constituents (M 2 , S 2 , K 1 , O 1 , and S a ). The accuracy of these new charts is believed to be significantly higher than the previous charts for the offshore area.
In vivo the application of optogenetic manipulation in deep tissue is seriously obstructed by the limited penetration depth of visible light that is continually applied to activate a photoactuator. Herein, we designed a versatile upconversion optogenetic nanosystem based on a blue-light-mediated heterodimerization module and rare-earth upconversion nanoparticles (UCNs). The UCNs worked as a nanotransducer to convert external deep-tissue-penetrating near-infrared (NIR) light to local blue light to noninvasively activate photoreceptors for optogenetic manipulation in vivo. In this, we demonstrated that deeply penetrating NIR light could be used to control the apoptotic signaling pathway of cancer cells in both mammalian cells and mice by UCNs. We believe that this interesting NIR-light-responsive upconversion optogenetic nanotechnology has significant application potentials for both basic research and clinical applications in vivo.
Optical imaging for biological applications is in need of more sensitive tool. Persistent luminescent nanophosphors enable highly sensitive in vivo optical detection and almost completely avoid tissue autofluorescence. Nevertheless, the actual persistent luminescent nanophosphors necessitate ex vivo activation before systemic operation, which severely restricted the use of long-term imaging in vivo. Hence, we introduced a novel generation of optical nanophosphors, based on (ZnSiO:Mn):Y, Yb, Tm upconverting persistent luminescent nanophosphors; these nanophosphors can be excited in vivo through living tissues by highly penetrating near-infrared light. We can trace labeled tumor therapeutic macrophages in vivo after endocytosing these nanophosphors in vitro and follow macrophages biodistribution by a simple whole animal optical detection. These nanophosphors will open novel potentials for cell therapy research and for a variety of applications in diagnosis in vivo.
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