The situation of coronavirus disease 2019 (COVID‐19) pandemic is rapidly evolving, and medical researchers around the globe are dedicated to finding cures for the disease. Drug repurposing, as an ...efficient way for drug development, has received a lot of attention. However, the huge amount of studies makes it challenging to keep up to date with the literature on COVID‐19 therapeutic development. This review addresses this challenge by grouping the COVID‐19 drug repurposing research into three large groups, including clinical trials, computational research, and in vitro protein‐binding experiments. Particularly, to facilitate future drug discovery and the creation of effective drug combinations, drugs are organized by their mechanisms of action and reviewed by their efficacy measured by clinical trials. Providing this subtyping information, we hope this review would serve the scientists, clinicians, and the pharmaceutical industry who are looking at the new therapeutics for COVID‐19 treatment.
Little is publicly known about the conditions surrounding the emergence of COVID in China. Using two nationally representative datasets, the China Family Panel Studies (CFPS) and the China Health and ...Retirement Longitudinal Study (CHARLS), we engage in a descriptive analysis of spatiotemporal patterns of lung and other diseases before 2019. In both datasets, the incidence of lung disease in 2018 was elevated in Hubei province relative to other provinces. The incidence of psychiatric and nervous system disease was elevated as well. Overall, the evidence is consistent with many possible explanations. One conjecture is that there was an outbreak of influenza in central China, which implies the conditions that increased the susceptibility to influenza also facilitated the later spread of COVID. Another conjecture, though less likely, is that COVID was circulating at low levels in the population in central China during 2018. This study calls for more investigation to understand the conditions surrounding the emergence of COVID.
Little is publicly known about the conditions surrounding the emergence of COVID in China. Using two nationally representative datasets, the China Family Panel Studies (CFPS) and the China Health and ...Retirement Longitudinal Study (CHARLS), we engage in a descriptive analysis of spatiotemporal patterns of lung and other diseases before 2019. In both datasets, the incidence of lung disease in 2018 was elevated in Hubei province relative to other provinces. The incidence of psychiatric and nervous system disease was elevated as well. Overall, the evidence is consistent with many possible explanations. One conjecture is that there was an outbreak of influenza in central China, which implies the conditions that increased the susceptibility to influenza also facilitated the later spread of COVID. Another conjecture, though less likely, is that COVID was circulating at low levels in the population in central China during 2018. This study calls for more investigation to understand the conditions surrounding the emergence of COVID.
Extensive studies on nanomedicines have been conducted for drug delivery and disease diagnosis (especially for cancer therapy). However, the intracellular and in vivo biofate of nanomedicines, which ...is significantly associated with their clinical therapeutic effect, is poorly understood at present. This is because of the technical challenges to quantify the disassembly and behaviour of nanomedicines. As a fluorescence- and distance-based approach, the Förster Resonance Energy Transfer (FRET) technique is very successful to study the interaction of nanomedicines with biological systems. In this review, principles on how to select a FRET pair and construct FRET-based nanomedicines have been described first, followed by their application to study structural integrity, biodistribution, disassembly kinetics, and elimination of nanomedicines at intracellular and in vivo levels, especially with drug nanocarriers including polymeric micelles, polymeric nanoparticles, and lipid-based nanoparticles. FRET is a powerful tool to reveal changes and interaction of nanoparticles after delivery, which will be very useful to guide future developments of nanomedicine.
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In this paper, novel remedial direct torque control (DTC) schemes are proposed for open-circuit faults in T-type neutral-point-clamping (T-NPC) three-level asymmetric six-phase permanent-magnet ...synchronous motor (PMSM) drives. First, a simplified space vector modulation (SVM) is designed and applied for DTC-controlled asymmetric six-phase drive, in such a way that both good current harmonic performance and fast dynamic response are available. Based on the SVM-DTC scheme, a remedial strategy is proposed for the open-circuit faults in phase windings. The key is to derive the relationship between the stator fluxes and the stator voltages of all phases under faulty condition. Then, a derived perturbation term is compensated for normal voltage references, and the fault-tolerant scheme is, thus, implemented without changing control structure of normal condition. The remedial DTC schemes are also studied and proposed for open-switch faults in T-NPC six-phase drives. The modulation methods are redesigned for the faults in half-bridge switches and NPC switches. The experiments are carried out on a laboratory prototype to verify the validity and performance of the proposed fault-tolerant control schemes.
•Comprehensively classify modification behaviors of decision makers into 3 categories using the constructed cooperative index and non-cooperative index.•Uninorm aggregation operator is used for ...decision weight updating, laying either reward or penalty on decision makers in accordance with their modification behavior.•In order to lay stricter behavior supervision on highly-weighted clusters, the adaptive weight updating scheme is formulated based on a uninorm aggregation operator with floating neutral element.
Consensus reaching process (CRP) has received increasing attention in recent years, as the demand for decision results with mutual agreement has greatly grown. With the current tendency to introduce e-democracy and public participation into decision making for public issues, decision makers from various backgrounds are more likely to encounter conflict when attempting to reach a consensus, especially under a multi-attribute large-scale group decision making framework. In order to improve the efficiency of the CRPs, different consensus models have been proposed. Specific patterns of behaviors presented by decision makers, such as non-cooperative behaviors and minority opinions, are also strictly supervised in these models. However, not every type of behaviors is specifically defined and given directed treatment, this includes the behavior of highly-weighted clusters, which may seriously bias group consensus. In this paper, we present a novel CRP model named uninorm-based comprehensive behavior classification (UBCBC) model with enhanced efficiency and rationality. First, a behavior classification model based on the calculation of a cooperative index and a non-cooperative index is proposed to classify three kinds of modification behaviors. Second, decision weights in the next iteration of the CRP are updated using a uninorm aggregation operator to reward or penalize the behaviors of clusters. Furthermore, a floating neutral element is introduced into the uninorm aggregation operator to lay stricter supervision upon highly-weighted clusters. Finally, an illustrative example and a numerical simulation are implemented to prove that this model is of high efficiency and feasibility.
This paper studies and proposes the vector space decomposition-based direct torque control (DTC) scheme for the T-type neutral-point-clamping (T-NPC) three-level inverters-fed double-stator-winding ...permanent magnet synchronous machine (PMSM) drive, which provides an effective solution for high-power high-reliability applications. The key is to propose a simple but effective space vector modulation (SVM) for DTC of T-NPC double-stator-winding drives-based two-step voltage vector synthesis, in such a way that good dynamic response and harmonic performance are obtained. The closed-loop controllers on harmonic subspace are incorporated to suppress the possible harmonics induced from back electromotive force and unbalanced parameters in phase windings of electrical machine. Furthermore, a hybrid current control is proposed for fault-tolerant operation of the T-NPC double-stator-winding PMSM drives under one-phase open-circuit conditions. In the hybrid current controller, the healthy winding still uses the SVM-DTC control while the faulty winding uses the closed-loop current controller to track the optimized current references. Both simulation and experimental results are presented to verify the performance of the proposed switching strategies and control schemes.
Abundant pyridinic nitrogen in the triazine units of covalent triazine frameworks (CTFs) is very useful in various heterogeneous catalysis reactions. Herein, a tunable CTF platform with the same ...porous structure was designed and synthesized to study the interaction between palladium/platinum (Pd/Pt) and pyridinic nitrogen of CTFs. The smaller Pd nanoparticles were formed because of the stronger interaction between Pd and pyridinic nitrogen atoms of CTFs, which is more beneficial for the separation of photogenerated electron–hole pairs. Moreover, the stronger interaction between the Pd nanoparticles and CTFs is also beneficial for photoelectron transfer. Under the same conditions, the hydrogen evolution rate of 1 wt % Pd@CTF-HC6 is up to 11 times more than that of 1 wt % Pt@CTF-HC6. The hydrogen evolution rate of 1 wt % Pd@CTF-N approaches 10 556 μmol h–1 g–1 and is about 5 times more than that of 1 wt % Pt@CTF-N.
El Niño/Southern Oscillation (ENSO) as the strongest tropical interannual signature has the most prominent impact on wintertime Pacific‐North American (PNA) teleconnection pattern. ENSO exhibits an ...increasing asymmetry in recent decades. This study quantifies its extratropical asymmetric impact on the amplitude of the PNA pattern, using a normalized asymmetry index defined as a ratio of asymmetric versus symmetric anomalies for El Niño and La Niña. Relative to the ENSO asymmetry, the extratropical asymmetric impact is largely amplified especially downstream by up to 82%. Such an amplification is attributed to noticeable increases, 83.6% (68.9%), in asymmetry of Rossby wave source (RWS) anomalies over two key regions of North Pacific, in which anomalous divergence induced by nonlinear condensational heating feedback and anomalous synoptic eddy forcing are two major contributors. The former contributes 39.3% (47.5%) over the western (eastern) North Pacific through increasing asymmetric RWS anomalies, while the latter contributes 29.5% (21.3%) through decreasing symmetric RWS anomalies.
Plain Language Summary
El Niño/Southern Oscillation (ENSO) as the strongest tropical interannual signature can cause prominent wintertime North American climate anomalies through Pacific‐North American (PNA) teleconnection pattern. El Niño and La Niña events as two opposite phases of ENSO are not mirror images of each other, with El Niño significantly stronger than La Niña in recent decades, due to the nonlinearities in the tropical air‐sea system. Such an ENSO asymmetry tends to induce El Niño to have more serious impact than La Niña. This asymmetric impact of ENSO events on the PNA pattern is quantitatively found in this study to be largely amplified especially downstream due to the nonlinearities within the extratropical atmosphere, with using a normalized asymmetry index defined as a ratio of the asymmetric versus symmetric anomalies for El Niño and La Niña. The amplification is attributed to noticeable increases in asymmetry of the Rossby wave source anomalies over North Pacific, in which anomalous divergence induced by nonlinear condensational heating feedback and anomalous synoptic eddy vorticity forcing are two major contributors. Given that ENSO is the primary source of seasonal predictability, the amplified asymmetric impact on the PNA pattern discovered in this study would be of predictive value for the North American climate anomalies.
Key Points
Relative to the El Niño/Southern Oscillation (ENSO) asymmetry, ENSO's asymmetric impact on the Pacific‐North American pattern is quantitatively found to be largely amplified by up to 82%
The amplified asymmetric impact is due to the noticeable increases in asymmetry of Rossby wave source (RWS) anomalies over North Pacific
Extratropical nonlinearities in condensational heating and synoptic eddy vorticity feedbacks are responsible for the asymmetric RWS increase
The rapid development of the modern economy has also brought huge impacts on water resources. So far, the water pollution situation in China has been serious. The water that meets the drinking water ...hygiene standards only accounts for 10%, and the national water resources has been polluted up to 50%. Moreover, the types of modern water pollution are increasing, and the degree of water pollution is gradually deepening. Faced with the above situation, this paper starts the analysis and preliminary treatment methods of the status quo, grade, and pollution types of water pollution, and takes a representative of activated sludge method and biofilm method as an example to carry out in-depth introduction and analysis, providing theoretical reserve for water pollution control and construction projects for the future.
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