Adenosine 5'-monophosphate-activated protein kinase-dependent mTOR pathway is involved in flavokawain B-induced autophagy in thyroid cancer cells.

Flavokawain B (FKB), a natural kava chalcone, shows potent antitumor activity in various types of cancer, although the mechanism of action remains unclear. In this study, we report that FKB has profound effects on the metabolic state of human thyroid cancer (TCa) cells, leading to high autophagy flux through upregulation of AMP-activated protein kinase, which in turn inhibits mTOR and activates Beclin-1 in TCa cells. We further report that the autophagy induced by FKB plays a prosurvival role in TCa cells both in vitro and in vivo. In conclusion, our findings provide evidence that combination treatment with FKB and pharmacological autophagy inhibitors will be a potential therapeutic strategy for the treatment of TCa.

Riboflavin-responsive multiple Acyl-CoA dehydrogenation deficiency in 13 cases, and a literature review in mainland Chinese patients.

Multiple Acyl-CoA dehydrogenation deficiency (MADD) is an autosomal recessive disorder of fatty acid oxidation and amino-acid metabolism. Most patients with late-onset MADD are well responsive to treatment with riboflavin, which is also termed as riboflavin-responsive MADD (RR-MADD). In this study, we summarized the clinical profiles and genetic features of 13 Chinese patients with RR-MADD and reanalyzed the existing data on RR-MADD patients in Mainland China. In a cohort comprising 13 patients, all were seen to present with severe muscular symptoms occasionally accompanied with mild involvements of extramuscular organs. A total of 18 mutations (13 reported and 5 novel) of the ETFDH gene were identified in this series of patients. Exon deletion/duplication was not found in all patients. ETF:QO expression from the muscle specimens was significantly decreased in all patients. At the time of this study the total number of RR-MADD cases had reached 148 in Mainland China since 2009. The muscle symptoms in Mainland China were similar to those in other regions. However, the common extramuscular symptoms were fatty liver and recurrent vomiting in mainland Chinese patients rather than encephalopathy found in Caucasian patients. A total of 68 mutations had been identified in 148 patients with RR-MADD. The c.250G>A had a high mutation frequency in Southern China, whereas c.770A>G and c.1227A>C were more geographically widespread hot spot mutations in Mainland China.

Robust integration of light-driven carbon quantum dots with bacterial cellulose enables excellent mechanical and antibacterial biodegradable yarn.

Due to the overuse of antimicrobial drugs, bacterial resistance became an urgent problem to be solved. In this study, carbon quantum dots (CQDs) with high photodynamic antibacterial activity were synthesized by a one-pot hydrothermal method and introduced into bacterial cellulose (BC) dispersion solution. Through a wet-spinning and wet-twisting processing strategy, bionic ordering nanocomposite macrofiber (BC/CQDs-based yarn) based on BC were obtained. The results showed that BC/CQDs-based yarn had excellent tensile strength (226.8 MPa) and elongation (22.2 %). Utilizing the light-driven generation of singlet oxygen (1O2) and hydroxyl radical (·OH), BC/CQDs-based yarn demonstrated remarkable antibacterial efficacy, with 99.9999 % (6 log, P < 0.0001) and 96.54 % (1.46 log, P < 0.0004) effectiveness against E. coli and S. aureus, respectively. At the same time, BC/CQDs-based yarn also displayed the characteristics of photothermal, fluorescent, and biodegradability. In summary, the application potential of BC/CQDs-based yarn is significant, opening up a new strategy for the development of sustainable green weaving and bio-based multi-function yarn.

Fabrication and Photothermal Actuation Performances of Electrospun Carbon Nanotube/Liquid Crystal Elastomer Blend Yarn Actuators.

Liquid crystal elastomers (LCEs) are a kind of polymer network that combines the entropic elasticity of polymer networks and the mesogenic unit by means of mild cross-linking. LCEs have been extensively investigated in various fields, including artificial muscles, actuators, and microrobots. However, LCEs are characterized by the poor mechanical properties of the light polymers themselves. In this study, we propose to prepare a carbon nanotube/liquid crystal elastomer (CNT/LCE) composite yarn by electrospinning technology and a two-step cross-linking strategy. The CNT/LCE composite yarn exhibits a reversible shrinkage ratio of nearly 70%, a tensile strength of 16.45 MPa, and a relatively sensitive response speed of ∼3 s, enabling a fast response by photothermal actuation. The research disclosed in this article may provide new insights for the development of artificial muscles and next-generation smart robots.

Neural Adaptive Distributed Formation Control of Nonlinear Multi-UAVs With Unmodeled Dynamics.

The problem of neural adaptive distributed formation control is investigated for quadrotor multiple unmanned aerial vehicles (UAVs) subject to unmodeled dynamics and disturbance. The quadrotor UAV system is divided into two parts: the position subsystem and the attitude subsystem. A virtual position controller based on backstepping is designed to address the coupling constraints and generate two command signals for the attitude subsystem. By establishing the communication mechanism between the UAVs and the virtual leader, a distributed formation scheme, which uses the UAVs' local information and makes each UAV update its position and velocity according to the information of neighboring UAVs, is proposed to form the required formation flight. By designing a neural adaptive sliding mode controller (SMC) for multi-UAVs, the compound uncertainties (including nonlinearities, unmodeled dynamics, and external disturbances) are compensated for to guarantee good tracking performance. The Lyapunov theory is used to prove that the tracking error of each UAV converges to an adjustable neighborhood of zero. Finally, the simulation results demonstrate the effectiveness of the proposed scheme.

Recent Advances in Consumer Behavior Theory: Shocks from the COVID-19 Pandemic.

Background: The COVID-19 pneumonia epidemic has had an enormous impact on people's lives, particularly aspects of life such as consumption, and has therefore brought new elements to the expansion of Consumer behavior theory. Methods: This paper searches the literature on consumption research conducted from 1981 to 2021, including sources such as CNKI, Wanfang, Google Scholar, and Web of Science. Through the exploration of the existing relevant literature, this article found that the COVID-19 pneumonia epidemic has had a profound impact on consumption willingness, consumption patterns, and consumption objects, and, as such, has newly expanded the theoretical model of consumer behavior. Results: Through reviewing the literature, this paper found some results. For example with regard to consumption patterns, early studies and the impact of COVID-19 was focused on online consumption, however in the context of COVID-19, scholars proposed paying attention to the combination of online and offline development. Conclusion: The COVID-19 pneumonia epidemic has had a profound effect on consumer behavior worldwide. Under the current economic depression, the government should take adequate measures in order to respond to the new changes in consumer behavior and therefore promote economic growth. For example, the government should encourage the combination of online and offline business operation modes to break the boundaries of customer groups and supply chains, so that consumers can buy anytime and anywhere.

Remarkably efficient charge transfer through a double heterojunction mechanism by a CdS-SnS-SnS2/rGO composite with excellent photocatalytic performance under visible light.

In this work, a novel CdS-SnS-SnS2/rGO photocatalyst with two tin valence states (Ⅱ and IV) was successfully synthesized by a one-pot solvothermal method. For comparison, CdS-SnS2/rGO (GCS2) with tin in only the IV valence state was made by the same method. Based on a series of characterizations, CdS, SnS and SnS2 were shown to be successfully loaded onto the rGO surface. The introduction of rGO may increase charge carrier separation. The degradation efficiency increased gradually with increasing rGO loading content, and the optimum photocatalytic activity was observed at 6.0 wt% rGO loading content (GCS1), which achieved the efficient removal (84.46%) of ibuprofen over 60 min. Compared with GCS2, the CdS-SnS-SnS2/rGO composite exhibited significantly improved photocatalytic performance, which can be ascribed to the formation of a double heterostructure. rGO worked as a transfer mediator to transfer electrons from the conduction band (CB) of SnS to the CB of SnS2 at the heterointerface, which then flowed to the CB of CdS because of another heterojunction, further enhancing the separation efficiency of photogenerated carriers. Therefore, this study highlights a novel double heterojunction system with a facial preparation method, visible light response and good recyclability, which is beneficial for environmental remediation.

Design of a Z-scheme g-C3N4/CQDs/CdIn2S4 composite for efficient visible-light-driven photocatalytic degradation of ibuprofen.

A novel Z-scheme photocatalyst consisting of acidified graphitic carbon nitrogen (ag-C3N4)/carbon quantum dots/CdIn2S4 (CN/CQDs/CIS) was successfully synthesized via a one-step hydrothermal method. The optimized CN-2/CQDs-3/CIS exhibited significantly improved photocatalytic performance in the degradation of ibuprofen under visible-light irradiation. Based on a series of characterizations, the ag-C3N4 and CQDs were distributed uniformly on the surface of the cubic spinel structure of CIS, with intimate contact among the materials. This intimate heterogeneous interface facilitated the migration of photogenerated carriers, further leading to enhanced photocatalytic performance. These results also indicated that the CQDs not only connect ag-C3N4 with CIS through covalent bonds but also enhance the visible-light adsorption. According to the analysis of the UV-vis diffuse reflectance spectra (DRS) and Mott-Schottky curves, the mechanism of the Z-scheme heterojunction is proposed. The CQDs serve as electron mediators and transfer the electrons in the conduction band (CB) of ag-C3N4 to recombine with the holes in the valence band (VB) of CIS in the Z-scheme, leading to the enhanced separation efficiency of the photogenerated electrons in the CB of ag-C3N4 and the holes in the VB of CIS. The pollutant IBU was degraded by h+, ·O2- and ·OH, as determined by electron paramagnetic resonance (EPR) analysis.