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We present a theoretical investigation of exciton-mediated Förster resonant energy transfers (FRET’s) from photoexcited quantum dots (QD’s) to transition-metal-dichalcogenide monolayers (TMD-ML’s), implemented by the quantum theory of FRET on the base of first-principles-calculated exciton fine structures. With the enhanced electron-hole Coulomb interactions, atomically thin TMD-ML’s are shown to serve as an exceptional platform for FRET that are mediated purely by excitons and take full advantage of the superior excitonic properties. Remarkably, the energy-transfer responses of atomically thin TMD-ML’s are shown to be dictated by the momentum-forbidden dark excitons rather than the commonly recognized bright ones. Specifically, the longitudinal dark exciton states following the exchange-driven light-like linear band dispersion play a key role in grading up the efficiency and robustness of FRET of TMDML against the inhomogeneity of QD-donor ensembles. With the essential involvement of dark exciton, the FRET responses of TMD-ML’s no longer follow the distance power law as classically predicted and, notably, cannot manifest the dimensionality of the donor-acceptor system.

Purpose: Some patients with respiratory failure fail initial weaning attempts and need prolonged mechanical ventilation (MV). Prolonged MV is associated with many complications and consumption of heathcare resources. Objective weaning indices help staffs to identify high-potential patients for weaning from the MV. Traditional weaning indices are not reliable in clinical practice. Transitional percentage of minute volume (TMV%) is a new index of the work of breathing. This study aimed to investigate the utility of TMV% in the prediction of weaning potential. Methods: This study was prospectively performed including all patients with prolonged MV. Researchers recorded their demographics, TMV%, respiratory parameters, Acute Physiology and Chronic Health Evaluation II score, and laboratory data upon arrival at the respiratory care center. The factors associated with successful weaning were analyzed. Results: Out of the 120 patients included, 84 (70.0%) were successfully weaned from MV. Traditional weaning indices such as rapid shallow breathing index could not predict the weaning outcome. TMV% was a valuable parameter as patients with a lower TMV%, higher tidal volume, higher hemoglobin, lower blood urea nitrogen, and lower Acute Physiology and Chronic Health Evaluation II scores had a higher rate of successful weaning. TMV%, tidal volume, and HCO3- levels were independent predictors of successful weaning, and the area under the curve was .79 in the logistic regression model. Conclusion: TMV% is a novel and effective predictor of successful weaning. Patients with lower TMV% had a higher MV weaning outcome. Once patients with a high potential for successful weaning are identified, they should be aggressively weaned from MV as soon as possible. Clinical Trials Government Identifier: NCT033480. Keywords: respiratory insufficiency, ventilators, mechanical, work of breathing

Recently, chiral structured illumination microscopy has been proposed to image fluorescent chiral domains at sub-wavelength resolution. Chiral structured illumination microscopy is based on the combination of structured illumination microscopy, fluorescence-detected circular dichroism, and optical chirality engineering. Since circular dichroism of natural chiral molecules is typically weak, the differential fluorescence is also weak and can be easily buried by the noise, hampering the fidelity of the reconstructed images. In this work, we systematically study the impact of the noise on the quality and resolution of chiral domain images obtained by chiral SIM. We analytically describe the signal-to-noise ratio of the reconstructed chiral SIM image in the Fourier domain and verify our theoretical calculations with numerical demonstrations. Accordingly, we discuss the feasibility of chiral SIM in different experimental scenarios and propose possible strategies to enhance the signal-to-noise ratio for samples with weak circular dichroism.

We propose double structured illumination microscopy (SIM) method, which enables simultaneous imaging of achiral and chiral domains at sub-wavelength resolution. In double SIM, the illumination field is spatially structured both in the intensity and optical chirality so that moiré effects can be concurrently generated on the achiral and chiral fluorescent domains of a sample. This allows for down-modulating the high spatial frequency of both domains at the same time and thus provides sub-wavelength details after image reconstruction. We introduce the working principle of double SIM and theoretically demonstrate the feasibility of this method using different kinds of synthetic samples.

We systematically investigate the generation of optical chirality patterns by applying the superposition of two waves in three scenarios, namely free-space plane waves, evanescent waves of totally reflected light at dielectric interface and propagating surface plasmon waves on a metallic surface. In each scenario, the general analytical solution of the optical chirality pattern is derived for different polarization states and propagating directions of the two waves. The analytical solutions are verified by numerical simulations. Spatially structured optical chirality patterns can be generated in all scenarios if the incident polarization states and propagation directions are correctly chosen. Optical chirality enhancement can be obtained from the constructive interference of free-space circularly polarized light or enhanced evanescent waves of totally reflected light. Surface plasmon waves do not provide enhanced optical chirality unless the near-field intensity enhancement is sufficiently high. The structured optical chirality patterns may find applications in chirality sorting, chiral imaging and circular dichroism spectroscopy.

background: Mechanical ventilation(MV) in patient with respiratory failure that can provide patient to keep adequate oxygenation and ventilation. After acute ilness, the number of patients requiring prolong MV has increased because they cannot be weaned from MV. It is poorly outcome that patients undergoing prolonged MV, and that is associated with various complications. Therefore, how to wean from MV as soon as possible is important issue. Transition MinVol% (TMV%) is an index of work breathing, and it means the transition of spontaneous breathing to mandatory breathing. Aim: We try to established a utility and accuracy weaning parameter to predicate weaning successful. Methods: This was a prospective study and included 120 adult patients between January,2017 and December,2017. All patients, using mechanical ventilator for at least 21 days and in stable hemodynamics condition, admitted to our 12-bed respiratory care center (RCC) in Taiwan. We recorded and analyzed their demographics, TMV%, respiratory parameters, APACHE II score, and laboratory data upon arrived at RCC. Results: Successful weaned from MV in 70% (84/120) of patients. Lower TMV% had higher successful weaning rate. Multivariate logistic regression analysis identified TMV%(OR=0.983, p=0.006); VT (OR=1.011, p Conclusions: TMV%, a novel respiratory parameter, is a useful predictor of weaning outcome in patients with prolonged MV.

We propose a chiral imaging modality based on optical chirality engineering, fluorescence-detected circular dichroism and structured illumination microscopy. In this method, the optical chirality of the illumination is structured and the circular dichroism dependent fluorescence is detected. With image reconstruction, the spatial distribution of chiral domains can be obtained at sub-diffraction limited resolution. We theoretically demonstrate this method and discuss the feasibility using an optical chirality engineering approach based on far-field optics., 5 pages, 3 Figures

The storage of the quantum bit, also called “qubit”, is a critical issue in the field of quantum information. As a promising candidate of being a quantum device, semiconductor quantum dots (QDs) are expected to play a central role in quantum information networks. Therefore, the study of quantum information storage in the QDs is really important. In this work, we employ the quantum master equation [1-2] to simulate the dynamics of the bright exciton, which is also used as a qubit, in coupled two QDs. In our model (shown in Fig. 1(a)), each QD is theoretically treated as a three-level subsystem and the exciton in this two-QD system is affected by the intrinsic electron-hole exchange interaction δ' ehxc and the dipole-dipole interactions for different exciton transfer δ' dd (change exciton spin after the transfer) and δ dd (do not change exciton spin after the transfer). We assume that the incident photon is absorbed by the QD1, which creates an exciton. However, the initial exciton spin state will be disturbed by the intrinsic electron-hole exchange interaction, repeatedly changing the status from spin up to spin down during the exciton lifetime.

Gorham syndrome is a rare disease that presents as progressive osteolysis, and may affect any part of the skeleton. The pathologic process involves the replacement of normal bone by aggressively expanding but non-neoplastic vascular tissue, resulting in massive osteolysis of the adjacent bone. If the spine and ribs are affected, the subsequent kyphosis and chest wall deformity may cause severe restrictive ventilatory impairment. We report a 34-year-old male with Gorham syndrome presenting as progressive kyphosis, severe back pain, unstable gait, and exertional dyspnea. Pulmonary function testing revealed severe restrictive ventilatory impairment. He underwent spinal surgery but could not be extubated after surgery. Postoperative left lower lung pneumonia and respiratory failure required prolonged mechanical ventilation. After a weaning program of pressure support ventilation and T-piece spontaneous breathing trials, he was successfully weaned from mechanical ventilation.