Summary Background Coronavirus disease 2019 (COVID-19) is a global pandemic but the follow-up data of discharged patients was barely described. Aim To investigate clinical outcomes, distribution of quarantine locations and the infection status of the contacts of COVID-19 patients after discharge. Design A prospective cohort study. Methods Demographics, baseline characteristics of 131 COVID-19 patients discharged from 3 February 2020 to 21 February 2020 in Wuhan, China were collected and analyzed by reviewing the medical records retrospectively. Post-hospitalization data related to clinical outcomes, quarantine locations and close contact history were obtained by following up the patients every week up to 4 weeks. Results Fifty-three (40.05%) patients on discharge had cough (29.01%), fatigue (7.63%), expectoration (6.11%), chest tightness (6.11%), dyspnea (3.82%), chest pain (3.05%) and palpitation (1.53%). These symptoms constantly declined in 4 weeks post-discharge. Transient fever recurred in 11 (8.4%) patients. Among the discharged patients, 78 (59.5%) underwent chest CT and 2 (1.53%) showed deterioration. A total of 94 (71.8%) patients received SARS-CoV-2 retest and 8 (6.10%) reported positive. Seven (2.29%) patients were readmitted because of fever or positive SARS-CoV-2 retest. After discharge, 121 (92.37%) and 4 (3.05%) patients were self-quarantined at home or community spots, respectively, after a close contact with 167 persons in total who were free of COVID-19 at the endpoint of study. Conclusion The majority of COVID-19 patients after discharge were in the course of recovery. Readmission was required in rare cases due to suspected recurrence of COVID-19. Although no contacted infection observed, appropriate self-quarantine and regular re-examination are necessary, particularly for those who have recurred symptoms.

Hole spin dephasing time due to the D'yakonov-Perel' mechanism in p-type GaAs ͑100͒ quantum wells with well separated light-hole and heavy-hole bands is studied by constructing and numerically solving the kinetic spin Bloch equations. We include all the spin-conserving scattering such as the hole-phonon and the holenonmagnetic impurity as well as the hole-hole Coulomb scattering in our calculation. Different effects such as the temperature, the hole density, the impurity density and the Rashba coefficient on the spin dephasing are investigated in detail. We also show that the Coulomb scattering makes a marked contribution to the spin dephasing. The spin dephasing time can either increase or decrease with temperature, hole/impurity density or the inclusion of the Coulomb scattering depending on the relative importance of the spin-orbit coupling and the scattering. It is also shown that due to the different spin-orbit coupling strengths, many spin dephasing properties of holes are quite different from those of electrons.

Quantum teleportation and quantum memory are two crucial elements for large-scale quantum networks. With the help of prior distributed entanglement as a "quantum channel," quantum teleportation provides an intriguing means to faithfully transfer quantum states among distant locations without actual transmission of the physical carriers [Bennett CH, et al. (1993) Phys Rev Lett 70 (13):1895-1899]. Quantum memory enables controlled storage and retrieval of fast-flying photonic quantum bits with stationary matter systems, which is essential to achieve the scalability required for large-scale quantum networks. Combining these two capabilities, here we realize quantum teleportation between two remote atomic-ensemble quantum memory nodes, each composed of ∼10 8 rubidium atoms and connected by a 150-m optical fiber. The spin wave state of one atomic ensemble is mapped to a propagating photon and subjected to Bell state measurements with another single photon that is entangled with the spin wave state of the other ensemble. Two-photon detection events herald the success of teleportation with an average fidelity of 88(7)%. Besides its fundamental interest as a teleportation between two remote macroscopic objects, our technique may be useful for quantum information transfer between different nodes in quantum networks and distributed quantum computing.cold atomic ensembles | long-distance quantum communication | quantum computation | light-matter interface S ingle photons are so far the best messengers for quantum networks as they are naturally propagating quantum bits (qubits) and have very weak coupling to the environment (1, 2). However, due to the inevitable photon loss in the transmission channel, the quantum communication is limited currently to a distance of about 200 km (3, 4). To achieve scalable long-distance quantum communication (5, 6), quantum memories are required (7-10), which coherently convert a qubit between light and matter efficiently on desired time points so that operations can be appropriately timed and synchronized. The connection of distant matter qubit nodes and transfer of quantum information between the nodes can be done by distributing atom-photon entanglement through optical channels and quantum teleportation (11).Optically thick atomic ensemble has been proved to be an excellent candidate for quantum memory (12-17), with promising experimental progress including the entanglement between two atomic ensembles (18, 19), generation of nonclassical fields (12, 13), efficient storage and retrieval of photonic qubits (14), subsecond storage time (17), and demonstration of a preliminary quantum repeater node (15,16). Quantum teleportation has been demonstrated with single photons (20)(21)(22), from light to matter (23,24), and between single ions (25-27). However, quantum teleportation between remote atomic ensembles has not been realized yet.In this article, we report a teleportation experiment between two atomic-ensemble quantum memories. The layout of our experiment is shown in Fig. 1. Two atomic e...