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Background: A cluster of patients with coronavirus disease 2019 (COVID-19) pneumonia were discharged from hospitals in Wuhan, China. We aimed to determine the cumulative percentage of complete radiological resolution at each time point, to explore the relevant affecting factors, and to describe the chest CT findings at different time points after hospital discharge.Methods: Patients with COVID-19 pneumonia confirmed by RT-PCR who were discharged consecutively from the hospital between 5 February 2020 and 10 March 2020 and who underwent serial chest CT scans on schedule were enrolled. The radiological characteristics of all patients were collected and analysed. The total CT score was the sum of non-GGO involvement determined at discharge. Afterwards, all patients underwent chest CT scans during the 1st, 2nd, and 3rd weeks after discharge. Imaging features and distributions were analysed across different time points.Results: A total of 149 patients who completed all CT scans were evaluated; there were 67 (45.0%) men and 82 (55.0%) women, with a median age of 43 years old (IQR 36-56). The cumulative percentage of complete radiological resolution was 8.1% (12 patients), 41.6% (62), 50.3% (75), and 53.0% (79) at discharge and during the 1st, 2nd, and 3rd weeks after discharge, respectively. Patients ≤44 years old showed a significantly higher cumulative percentage of complete radiological resolution than patients > 44 years old at the 3-week follow-up. The predominant patterns of abnormalities observed at discharge were ground-glass opacity (GGO) (125 [83.9%]), fibrous stripe (81 [54.4%]), and thickening of the adjacent pleura (33 [22.1%]). The positive count of GGO, fibrous stripe and thickening of the adjacent pleura gradually decreased, while GGO and fibrous stripe showed obvious resolution during the first week and the third week after discharge, respectively. "Tinted" sign and bronchovascular bundle distortion as two special features were discovered during the evolution.Conclusion: Lung lesions in COVID-19 pneumonia patients can be absorbed completely during short-term follow-up with no sequelae. Two weeks after discharge might be the optimal time point for early radiological estimation. [ABSTRACT FROM AUTHOR]

Novel mesogenic [60]fullerenes have been synthesized and doped into cholesteric liquid crystals (CLCs) to achieve a dual-mechanism laser protection system that is effective for both pulsed and broadband cw lasers, simultaneously. It was found that this system integrated a good OPL response, broadband protection range, and high practicability with great potentials in flexible and even wearable protection devices. [ABSTRACT FROM AUTHOR]

To diagnose breast cancer, the number of mitotic cells present in histology sections is an important indicator for examining and grading biopsy specimen. This study aims at improving the accuracy of automated mitosis detection by characterizing mitotic cells in wavelet based multi-resolution representations via a non-Gaussian modeling method. The potential mitosis candidates were decomposed into multi-scale forms by an undecimated dual-tree complex wavelet transform. Two non-Gaussian models (the generalized Gaussian distribution (GGD) and the symmetric alpha-stable (S α S) distributions) were used to accurately model the heavy-tailed behavior of wavelet marginal distributions. The method was evaluated on two independent data cohorts, including the benchmark dataset (MITOS), via a support vector machine classifier. The quantitative results shows that the bivariate S α S model achieved superior classification performance with the area under the curve value of 0.82 in comparison with 0.79 for bivariate GGD, 0.77 for univariate S α S, 0.72 for univariate GGD, and 0.59 for Gaussian model. Since both mitotic and non-mitotic cells appear as small objects with a large variety of shapes, characterization of mitosis is a hard problem. The inter-scale dependencies of wavelet coefficients allowing extraction of salient features within the cells that are more likely to appear at all different scales were captured by the bivariate non-Gaussian models, leading to more accurate detection results. The presented automated mitosis detection method might assist pathologists in enhancing the operational efficiency and productivity as well as improving diagnostic confidence. [ABSTRACT FROM AUTHOR]

A novel series of dichroic anthraquinone dyes have been successfully synthesised with conventional Sonogashira reaction. These synthesised anthraquinone dyes were found to have high dichroic ratios, good solubilities, excellent hues and to be potential candidates for guest–host liquid crystal displays. The dichroic ratio is as high as 13.26, which is in the top level of the anthraquinone dyes reported so far. In addition, this paper provides an effective method to modulate the optic properties of anthraquinone dyes from the molecular level via the introduction of different radicals on the anthraquinone cores. [ABSTRACT FROM AUTHOR]

Abstract: A series of novel donor–acceptor chromophores have been successfully synthesized in excellent yield by metal-free [2+2] click chemistry, which was effective in the energy-level modulation. Structures of the conjugated compounds were fully characterized by NMR, IR, and MS. By introducing TCNE, TCNQ, F4-TCNQ click monomers, we obtained energy-level tunable materials in high solubility, which was beneficial for processing. It has been demonstrated that the absorption characteristics of all the newly prepared compounds have been strongly bathochromically shifted with an end-absorption far into the near infrared region due to the efficient intramolecular charge-transfer (CT) interaction. The electrochemical properties have been studied by cyclic voltammograms indicating good agreement between the electrochemical and optical band gaps determined by the end absorption. [Copyright &y& Elsevier]

High-performance and cost-effective laser protection system is of crucial importance for the rapid advance of lasers in military and civilian fields leading to severe damages of human eyes and sensitive optical devices. However, it is crucially hindered by the angle-dependent protective effect and the complex preparation process. Here we demonstrate that angle-independence, good processibility, wavelength tunability, high optical density and good visibility can be effectuated simultaneously, by embedding dichroic anthraquinone dyes in a cholesteric liquid crystal matrix. More significantly, unconventional two-dimensional parabolic protection behavior is reported for the first time that in stark contrast to the existing protection systems, the overall parabolic protection behavior enables protective effect to increase with incident angles, hence providing omnibearing high-performance protection. The protective effect is controllable by dye concentration, LC cell thickness and CLC reflection efficiency, and the system can be made flexible enabling applications in flexible and even wearable protection devices. This research creates a promising avenue for the high-performance and cost-effective laser protection, and may foster the development of optical applications such as solar concentrators, car explosion-proof membrane, smart windows and polarizers. [ABSTRACT FROM AUTHOR]

Molecular imaging can allow the non-invasive characterization and measurement of biological and biochemical processes at the molecular and cellular levels in living subjects. The imaging of specific molecular targets that are associated with cancers could allow for the earlier diagnosis and better treatment of diseases. Small molecule-based probes play prominent roles in biomedical research and have high clinical translation ability. Here, with an emphasis on small molecule-based probes, we review some recent developments in biomarkers, imaging techniques and multimodal imaging in molecular imaging and highlight the successful applications for molecular imaging of cancers. [ABSTRACT FROM AUTHOR]

Thin films of a nematic liquid crystal doped with three commercially available azobenzene dichroic dyes were successfully fabricated and their electro-optical properties as well as their selective optical absorptive characteristics were explored in detail. The experimental results showed that the films had a lower and higher transmittance of incident light across the whole visible region without and with an electric field applied, respectively. The transmittance of the light decreased with the increase in both the dye-doped concentration and the cell thickness. Moreover, the transmittances of the films from a continuous wave lasers (λ = 532 nm) were also studied, which exhibited the potential application as a laser protective material to protect against the damage to the sensor or human’s eye from a laser. [ABSTRACT FROM PUBLISHER]

A photo-responsive macroscopic switch was fabricated using a chiral azo-calix[4]arene derivative (FC4AD) functionalized silicon surface and exhibited selective and reversible recognition of (1R,2S)-1-amino-2-indanol through the variation of wettability. This photo-responsive device may have wide applications in controlled release of chiral drugs and in biosensors. [ABSTRACT FROM AUTHOR]

Abstract: Dynamic controllability of self‐organized helical superstructures in spatial dimensions is a key step to promote bottom‐up artificial nanoarchitectures and functional devices for diverse applications in a variety of areas. Here, a light‐driven chiral overcrowded alkene molecular motor with rod‐like substituent is designed and synthesized, and its thermal isomerization reaction exhibits an increasing structural entropy effect on chemical kinetic analysis in anisotropic achiral liquid crystal host than that in isotropic organic liquid. Interestingly, the stimuli‐directed angular orientation motion of helical axes in the self‐organized helical superstructures doped with the chiral motors enables the dynamic reconfiguration between the planar (thermostationary) and focal conic (photostationary) states. The reversible micromorphology deformation processes are compatible with the free energy fluctuation of self‐organized helical superstructures and the chemical kinetics of chiral motors under different conditions. Furthermore, stimuli‐directed reversible nonmechanical beam steering is achieved in dynamic hidden periodic photopatterns with reconfigurable attributes prerecorded with a corresponding photomask and photoinduced polymerization. [ABSTRACT FROM AUTHOR]

[Display omitted] • CeO 2 QDs modified g-C 3 N 4 was fabricated. • The addition of CeO 2 QDs promotes the photocatalytic performance of as-prepared catalysts. • This work extends the application of quantum dots in catalyst modification. Cerium dioxide quantum dots (CeO 2 QDs) modified graphitic carbon nitride (g-C 3 N 4) was fabricated by a facile chemical reaction with urea and cerium nitrate hexahydrate as precursors. Combined X-ray diffraction (XRD), UV–Vis DRS, transmission electron microscopy (TEM), photoluminescence spectroscopy (PL), Electrochemical impedance spectra (EIS), Thermogravimetric analysis (TGA), Brunner-Emmet-Teller (BET) measurements and X-ray photoelectron spectroscopy (XPS) studies showing that CeO 2 QDs dispersed homogeneously on the g-C 3 N 4 surface, which enhanced the absorption in visible light region. Specifically, we found that CeO 2 QDs/g-C 3 N 4 shows much lower electron-hole recombination rate, and its Rhodamine B photodegradation rate constant can reach 0.00985 min−1, which is 7 times higher than that of single g-C 3 N 4. In addition, the CeO 2 QDs/g-C 3 N 4 displayed outstanding catalytic stability. Furthermore, the CeO 2 QDs/g-C 3 N 4 catalyst also exhibited the excellent photodegradation performance on other substrates such as TC, Methyl Orange, and Methyl Blue. It was proposed that the CeO 2 QDs/g-C 3 N 4 photocatalyst could follow a more appropriate Z-scheme charge transfer mechanism. Our studies extend the application of Quantum dots nanocomposite catalyst and pave the way for its further rational design. [ABSTRACT FROM AUTHOR]