The recently emerged novel coronavirus pneumonia, named the coronavirus disease 2019 (COVID-19), shares several clinical characteristics with severe acute respiratory syndrome (SARS) and Middle East ...respiratory syndrome (MERS), and spread rapidly throughout China in December of 2019 (Huang et al., 2020). The pathogen 2019 novel coronavirus (2019-nCoV) is now named SARS coronavirus 2 (SARS-CoV-2) and is highly infectious. As of Apr. 9, 2020, over 80 000 confirmed cases had been reported, with an estimated mortality rate of 4.0% (Chinese Center for Disease Control and Prevention, 2020). Person-to-person transmission and familial clustering have been reported (Chan et al., 2020; Nishiura et al., 2020; Phan et al., 2020). However, there is no evidence of fetal intrauterine infection in pregnant women who have been infected with SARS-CoV-2 in their third trimester (Chen et al., 2020). It is unclear whether breastfeeding transmits the virus from previously infected and recovered mothers to their babies. Here we report the clinical course of a pregnant woman with COVID-19. In order to determine whether SARS-CoV-2 can be transmitted to newborns through breastfeeding, we measured viral RNA in the patient's breastmilk samples at different time points after delivery.
Cotton cultivars have evolved to produce extensive, long, seed-born fibers important for the textile industry, but we know little about the molecular mechanism underlying spinnable fiber formation. ...Here, we report how PACLOBUTRAZOL RESISTANCE 1 (PRE1) in cotton, which encodes a basic helix-loop-helix (bHLH) transcription factor, is a target gene of spinnable fiber evolution.
Differential expression of homoeologous genes in polyploids is thought to be important to plant adaptation and novel phenotypes. PRE1 expression is specific to cotton fiber cells, upregulated during their rapid elongation stage and A-homoeologous biased in allotetraploid cultivars. Transgenic studies demonstrated that PRE1 is a positive regulator of fiber elongation.
We determined that the natural variation of the canonical TATA-box, a regulatory element commonly found in many eukaryotic core promoters, is necessary for subgenome-biased PRE1 expression, representing a mechanism underlying the selection of homoeologous genes.
Thus, variations in the promoter of the cell elongation regulator gene PRE1 have contributed to spinnable fiber formation in cotton. Overexpression of GhPRE1 in transgenic cotton yields longer fibers with improved quality parameters, indicating that this bHLH gene is useful for improving cotton fiber quality.
Fried fish skins are snacks with rich flavor in Asian. However, the high fat content about 50% is not good for health. It is possible to reduce the oil content while maintain its fried taste and ...texture by optimized frying methods. The effects of different frying approaches such as air frying, vacuum frying, electrostatic frying and traditional deep-fat frying on the oil uptake, moisture loss, breaking force, color, and microstructure attributes of fried fish skins were studied. Air and oil frying were performed at 180 °C for 2–12 min. Vacuum frying was conducted at lower temperature 120 °C for 4–24 min. Results showed that air fried and vacuum fried fish skins had the lowest fat contents (9.8% and 27.7%, respectively) and showed smooth, uniform microstructures. On the contrary, holy, irregular and non-uniform microstructures were obtained by traditional deep-fat frying and electrostatic frying due to high heat and rapid mass transfer occurred. The oil uptake (47.6% and 46.3% fat content, respectively) and browning reactions were also significant. Air frying developed a slower water evaporation rate and higher fish skin puffing ratio, which was suggested to be an alternative to traditional deep-fat frying.
•Air and vacuum frying significantly reduce oil content of fish skin but take more time.•Air and vacuum frying obtained 73% and 39% less fat than deep-fat fried fish skin.•Kinetic equations for water loss and oil uptake for fried fish skin are established.•Negative relationship between oil absorption and water loss during frying was found.
In differential evolution (DE) studies, there are many parameter adaptation methods, aiming at tuning the mutation factor F and the crossover probability CR. However, these methods still cannot ...resolve the issues of population premature convergence and population stagnation. To address these issues, in this paper, we investigate the population adaptation regarding population diversity at the dimensional level and propose a mechanism named auto-enhanced population diversity (AEPD) to automatically enhance population diversity. AEPD is able to identify the moments when a population becomes converging or stagnating by measuring the distribution of the population in each dimension. When convergence or stagnation is identified at a dimension, the population is diversified at that dimension to an appropriate level or to eliminate the stagnation issue. The AEPD mechanism was incorporated into a popular DE algorithm and it was tested on a set of 25 CEC2005 benchmark functions. The results showed that AEPD significantly improved the performance of the original algorithms. In addition, AEPD helped the algorithms become less sensitive to population size, a parameter widely considered problem dependent for many DE algorithms. The DE algorithm with AEPD also has a superior performance in comparison with several other peer algorithms.
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•Detection method and driving strategy of shape memory alloy wires are discussed.•An improved phase transformation equation with the Logistic function is proposed.•SMA wires electric ...resistance and its rate are studied in theory and experiment.•Phase transformation start/end points are detected by electric resistance method.•Optimized driving strategy is proposed to reduce power consumption of SMA wires.
To propose a novel driving strategy for power consumption reduction, this paper studies the electric resistance behaviors of shape memory alloy (SMA) wires, which are heated by the short-time large current. With a concern for the relationship between electric resistance and shape memory effect, an improved phase transformation equation with the Logistic function is proposed. Moreover, based upon electric resistance and its rate, a new detection method for the driving strategy of SMA wires is proposed. The proposed method is compared with the traditional deformation detection method. The results show that the method effectively resists the interference of system noise and captures the start and end points of phase transformation. To assess the deformation response of SMA wires by the proposed method, constant load tests are conducted, which are applied with the periodic excitation signals of triangular wave, sine wave, and square wave, respectively. The experimental results show the square wave is more suitable for driving the SMA wire actuator. The heating and cooling cycle experiment verifies the effectiveness of the proposed method. Compared with the method using pulse width modulation signals, the proposed method reduces power consumption obviously, and does not need external sensors or material parameters. Based on the proposed method, the power consumption can be reduced by the optimized driving strategy, which improves the lightweight and reliability of SMA actuators.
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•Electron-trapped oxygen vacancy was introduced in Ti/TiO2-001 by H2 reduction.•Increasing electron-trapped oxygen vacancy in Ti/TiO2-001 enhanced its reduction activity.•The ...synergistic role between electron-trapped oxygen vacancy and 001 facets was proposed.•Electron-trapped oxygen vacancy on TiO2 acted as adsorption site and reactivity sites.
Despite the fact that electron-trapped oxygen vacancy and 001 facets fundamentally affect the reactivity of TiO2, their synergistic role in the electrochemical activity of TiO2 toward p-nitrophenol (p-NP) reduction is still unknown. In this study, defective and 001 facets engineered TiO2 cathode, i.e. Ti/TiO2−x-001, was prepared for p-NP reduction. In comparison to defective Ti/TiO2 cathode with 101 facets (Ti/TiO2−x-101), the combination of the electron-trapped oxygen vacancy and 001 facets exhibited a synergistic effect to improve the electrochemical reduction efficiency of TiO2. Density functional theory calculations verified that the introduction of 001 facets and electron-trapped oxygen vacancy on TiO2 was beneficial to facilitate electron transfer and improve the indirect reduction efficiency for p-NP electrochemical reduction. Moreover, the electron-trapped oxygen vacancy extent of Ti/TiO2−x-001 was modulated by adjusting reduction temperature (250–650 °C). The maximum electron-trapped oxygen vacancy amount of Ti/TiO2−x-001 was attained at the reduction temperature of 350 °C, which resulted in the highest p-NP reduction efficiency of 99.3%, accompanying the p-AP selectivity of 89.5%. In this case, the abundant active and adsorption sites were provided on the surface of Ti/TiO2−x-001 prepared at 350 °C, in which p-NP adsorption coefficient and electrochemical surface area increased to 1.01 L mg−1 and 25 cm2, respectively. Generally, this work provides a paradigm for the design of efficient non-metallic catalyst for nitroaromatic chemicals reduction.
This article proposes a multiple self-sensing gripper (MssGripper) driven by the shape memory alloy (SMA) and empowered by machine learning algorithms. The MssGripper can identify objects without ...external sensors. A single SMA wire can drive the gripper for self-sensing accurately. This article confirms the resistance of the SMA can reflect the phase transition and can be used for displacement and force prediction, as well as for object stiffness prediction. Through machine learning, a backpropagation neural network and long-short-term-memory (LSTM) are used to establish multiple self-sensing models for prediction. The robustness experimental results show that the self-sensing models based on LSTM have higher prediction accuracy. The average root-mean-square errors of displacement prediction and force prediction are 0.063 mm and 0.236 N, respectively, and the stiffness prediction error is less than 9.4%. Moreover, the accuracy of the classifier in stiffness identification is 97.2%. The MssGripper can accurately predict the displacement, force, and stiffness and identify objects such as springs, rubber bars and steel bars. The establishment of the models expands the novel idea of gripper sensing, which is beneficial to promoting miniaturization and compactness.
Epithelial-to-mesenchymal transition (EMT) of epithelium and airway epithelial cell proliferation disorder are key events in idiopathic pulmonary fibrosis (IPF) pathogenesis. During EMT, epithelial ...cell adhesion molecules (EpCAM, such as E-cadherin) are downregulated, cytokeratin cytoskeletal transforms into vimentin-based cytoskeleton, and the epithelial cells acquire mesenchymal morphology. In the present study, we show abnormal upregulation of tumor protein p63 (TP63) and downregulation of miR-184 in IPF. Transforming growth factor beta 1 (TGF-β1) stimulation of BEAS-2B and A549 cell lines significantly increased the protein levels of Tp63, alpha-smooth muscle actin (α-SMA), and vimentin, but decreased EpCAM protein levels, and promoted viability of both BEAS-2B and A549 cell lines. TP63 knockdown in BEAS-2B and A549 cell lines significantly attenuated above-described TGF-β1-induced fibrotic changes. miR-184 targeted TP63 3′-UTR to inhibit Tp63 expression. miR-184 overexpression within BEAS-2B and A549 cell lines also attenuated TGF-β1-induced fibrotic changes. miR-184 overexpression attenuated bleomycin-induced pulmonary fibrosis in mice. Moreover, TP63 overexpression aggravated TGF-β1-stimulated fibrotic alterations within BEAS-2B and A549 cells and significantly reversed the effects of miR-184 overexpression, indicating miR-184 relieves TGF-β1-stimulated fibrotic alterations within BEAS-2B and A549 cells by targeting TP63, while TP63 overexpression reversed miR-184 cellular functions. In conclusion, the miR-184/TP63 axis modulates the TGF-β1-induced fibrotic alterations in epithelial cell lines and bleomycin-induced pulmonary fibrosis in mice. Therefore, these results confirm that the miR-184/TP63 axis is involved in IPF progression.
Epithelial-to-mesenchymal transition of epithelium and airway epithelial cell proliferation disorder are key events in idiopathic pulmonary fibrosis (IPF) pathogenesis. In the present study, the miR-184/TP63 axis modulates the TGF-β1-induced fibrotic alterations in epithelial cell lines and bleomycin-induced pulmonary fibrosis in mice, confirming that miR-184/TP63 axis is involved in IPF progression.
Developing high‐voltage Mg‐compatible electrolytes (>3.0 V vs Mg) still remains to be the biggest R&D challenge in the area of nonaqueous rechargeable Mg batteries. Here, the key design concepts ...toward exploring new boron‐based Mg salts in a specific way of highlighting the implications of anions are proposed for the first time. The well‐defined boron‐centered anion‐based magnesium electrolyte (BCM electrolyte) is successfully presented by facile one‐step mixing of tris(2H‐hexafluoroisopropyl) borate and MgF2 in 1,2‐dimethoxyethane, in which the structures of anions have been thoroughly investigated via mass spectrometry accompanied by NMR and Raman spectra. The first all‐round practical BCM electrolyte fulfills all requirements of easy synthesis, high ionic conductivity, wide potential window (3.5 V vs Mg), compatibility with electrophilic sulfur, and simultaneously noncorrosivity to coin cell assemblies. When utilizing the BCM electrolyte, the fast‐kinetics selenium/carbon (Se/C) cathode achieves the best rate capability and the sulfur/carbon (S/C) cathode exhibits an impressive prolonged cycle life than previously published reports. The BCM electrolyte offers the most promising avenue to eliminate the major roadblocks on the way to high‐voltage Mg batteries and the design concepts can shed light on future exploration directions toward high‐voltage Mg‐compatible electrolytes.
The well‐designed all‐round practical Mg‐ion electrolyte fulfills all requirements of easy synthesis, high ionic conductivity, wide potential window up to 3.5 V versus Mg, compatibility with high‐capacity selenium and sulfur active materials, and simultaneously noncorrosivity to coin cell assemblies.
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