Minerals and transitional metal oxides of earth-abundant elements are desirable catalysts for in situ chemical oxidation in environmental remediation. However, catalytic activation of peroxydisulfate ...(PDS) by manganese oxides was barely investigated. In this study, one-dimension manganese dioxides (α- and β-MnO2) were discovered as effective PDS activators among the diverse manganese oxides for selective degradation of organic contaminants. Compared with other chemical states and crystallographic structures of manganese oxide, β-MnO2 nanorods exhibited the highest phenol degradation rate (0.044 min–1, 180 min) by activating PDS. A comprehensive study was conducted utilizing electron paramagnetic resonance, chemical probes, radical scavengers, and different solvents to identity the reactive oxygen species (ROS). Singlet oxygen (1O2) was unveiled to be the primary ROS, which was generated by direct oxidation or recombination of superoxide ions and radicals from a metastable manganese intermediate at neutral pH. The study dedicates to the first mechanistic study into PDS activation over manganese oxides and provides a novel catalytic system for selective removal of organic contaminants in wastewater.
With the rapid development of Virtual Reality (VR) technology, its application in the field of sports training is also receiving increasing attention. This study applies the Distance Likelihood Based ...Probabilistic Model Averaging (DLPMA) algorithm to the VR motion intelligent capture system, aiming to provide an efficient and accurate motion data collection method to improve existing sports training methods. Introduced the design and implementation of a VR motion intelligent capture system based on DLPMA algorithm, and applied it to sports training. By conducting comparative experiments with traditional training methods, the advantages of the system in motion capture accuracy, real-time performance, and user experience are verified. The research results indicate that the system can accurately capture the movements of athletes and provide timely feedback to users, providing an effective auxiliary means for sports training. Although the system has shown good performance in sports training, there are still some limitations. Future research can further optimize algorithms, enhance system stability and flexibility, to meet a wider range of sports training needs.
Generation of hydroxyl radicals in the Fenton system (FeII/H2O2) is seriously limited by the sluggish kinetics of FeIII reduction and fast FeIII precipitation. Here, boron crystals (C‐Boron) ...remarkably accelerate the FeIII/FeII circulation in Fenton‐like systems (C‐Boron/FeIII/H2O2) to produce a myriad of hydroxyl radicals with excellent efficiencies in oxidative degradation of various pollutants. The surface B−B bonds and interfacial suboxide boron in the surface B12 icosahedra are the active sites to donate electrons to promote fast FeIII reduction to FeII and further enhance hydroxyl radical production via Fenton chemistry. The C‐Boron/FeIII/H2O2 system outperforms the benchmark Fenton (FeII/H2O2) and FeIII‐based sulfate radical systems. The reactivity and stability of crystalline boron is much higher than the popular molecular reducing agents, nanocarbons, and other metal/metal‐free nanomaterials.
The unique B12 unit of crystalline boron experiences step‐wise cleavage of B−B bond and rapidly provides electrons for FeIII reduction to FeII. This boosts the oxidation capability of the Fenton systems remarkably to oxidize a diversity of organic pollutants with exceptional stability.
Through the analysis of emotional tendency in online public opinion, governments and enterprises can stabilize people’s emotion more effectively and maintain social stability. The problem studied in ...this paper is how to analyze the emotional tendency of online public opinion efficiently, and finally, this paper chooses deep learning algorithm to perform fast analysis of emotional tendency of online public opinion. This paper briefly introduced the structure of the basic model used for emotional tendency analysis of online public opinion and the convolutional neural network (CNN) model used for text emotion classification. Then, the CNN model was improved by long short-term memory (LSTM). A simulation experiment was carried out on MATLAB for the improved text emotion classification model to verify the influence of activation function type on the improved model and the performance difference between the improved model and support vector machine (SVM) and traditional CNN models. The results showed that the improved classification model that adopted the sigmoid activation function had higher accuracy and was less affected by language than the relu and tanh activation functions; the improved classification model had the highest accuracy, recall rate, and
-value in classifying emotional tendency of web texts, followed by the traditional CNN model and the SVM model.
Density functional theory calculations were performed to investigate the copper-catalyzed borocyanation of 2-aryl-substituted 1,3-dienes. The computations show that the regioselectivity of the ...overall reaction is governed by the combination of the inherent regioselectivity of the borocupration and electrophilic cyanation steps. The π-conjugation effect of the 1,3-diene makes the terminal carbon atoms more electrophilic compared with the internal carbon atoms, which coupled with the steric effect results in the 4,3- and 1,2-borocupration being intrinsically more favorable than the other possibilities. The steric repulsion around the breaking Cu–C bond was found to be the key factor in determining the regioselectivity of the electrophilic cyanation. The origins of the experimentally observed ligand-controlled regioselectivity were ascribed to the electronic and steric effects. For the bulky XantPhos ligand, the 4,3-borocupration was found to be more favorable than the 1,2-borocupration due to the steric repulsion around the forming Cu–C bond, resulting in the formation of the 4,3-borocyantion product. On the other hand, the reversed regioselectivity with a small PCy3 ligand is mainly caused by the electronic effect that the π-electron-withdrawing aryl group at the C2 atom makes the C1 atom more electrophilic than the C4 atom, enabling the 1,2-borocupration to be more favorable than the 4,3-borocupration.
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•Fed-batch strategy increased 41.5% lipid productivity without compromising biomass.•Carbon dependent kinetics under stress conferred cells with a higher biomass.•Central carbon ...metabolism offered energy and carbon availability for lipid synthesis.•Sufficient precursor and active synthetic pathway promoted lipid content.•Fed-batch strategy was attractive by understanding lipid metabolism in detail.
To improve lipid and astaxanthin productivity without compromising biomass during the whole cultivation period, carbon-dependent kinetics involving nitrogen stress was applied under excess light to elevate intracellular carbon availability and metabolic activity of Chromochloris zofingiensis. Results suggested that fed-batch strategy proposed could increase lipid and astaxanthin productivity to 457.1 and 2.0 mg L−1 d−1, respectively. Biomass productivity at 1084.3 mg L−1 d−1 was comparable with that under suitable condition. Then 13C tracer-based metabolic flux analysis (13C-MFA) demonstrated that central carbon metabolism provided ATP, NADPH and carbon availability for lipid biosynthesis during the strategy. In combination with targeted metabolite analysis, 13C-MFA revealed that the strategy improved precursor content for lipid biosynthesis and elevated path rate to synthesize C16:0 and C18:0. The enhanced lipid content potentially accounted for the high biomass productivity. Therefore, comprehensively understanding relationships between carbon availability and carbon conversion could precisely design strategy for productivity improvements during cultivation.
Circular RNAs (circRNAs) possess important regulatory effects on multiple myeloma (MM) progression. Here, we aimed at exploring the function of circ_0007841 in MM and the underlying molecular ...mechanism. Expression of circ_0007841, microRNA (miR)-129-5p and Jagged1 (JAG1) was determined via qRT-PCR or western blot assay. Methyl thiazolyl tetrazolium (MTT) assay was applied to examine cell viability and IC50 value of MM cells to bortezomib (BTZ). Colony formation assay was performed to analyze cell proliferation. Moreover, cell apoptosis was assessed by flow cytometry and western blot analysis. Cell metastasis was evaluated by wound healing assay and Transwell assay. Function of circ_0007841 in vivo was determined by xenograft tumor assay. Target relationship between miR-129-5p and circ_0007841 or JAG1 was confirmed via dual-luciferase reporter, RNA immunoprecipitation (RIP) and pull-down assays. The up-regulation of circ_0007841 and JAG1, and the down-regulation of miR-129-5p were detected in MM bone marrow aspirates and cells. Circ_0007841 knockdown significantly repressed cell proliferation, chemoresistance, and metastasis, while contributed to apoptosis of MM cells in vitro, and reduced tumor growth in vivo. Circ_0007841 targeted miR-129-5p, and miR-129-5p inhibition reversed impact of silencing of circ_0007841 on MM cells. JAG1 was a mRNA target of miR-129-5p, whose overexpression could undermine the miR-129-5p-mediated effects on MM cells. Circ_0007841 positively regulated JAG1 expression via absorbing miR-129-5p. Circ_0007841 knockdown inhibited MM cell proliferation, metastasis and chemoresistance through modulating miR-129-5p/JAG1 axis, suggesting that circ_0007841 might serve as a potential therapeutic target of MM.
Bioaugmentation is a promising method for assisting phytoextraction of heavy metals from contaminated soil, and the development of bioaugmentation-assisted phytoextraction requires the understanding ...of the mechanism involved in the interaction between plants and inocula. In this study, a pot study was conducted to evaluate the effect of bacterial endophyte Pseudomonas sp. Lk9 which can produce biosurfactants, siderophores and organic acids on the growth and metal uptake of Cd-hyperaccumulator Solanum nigrum L. growing in multi-metal-contaminated soil. The results revealed that Lk9 inoculation could improve soil Fe and P mineral nutrition supplies, enhance soil heavy metal availability, and affect host-mediated low-molecular-weight organic acids secretion, thereby significantly increasing S. nigrum shoot dry biomass by 14% and the total of Cd by 46.6%, Zn by 16.4% and Cu by 16.0% accumulated in aerial parts, compared to those of non-inoculated control. The assessment of phytoextraction showed that Lk9 inoculation elevated the bioaccumulation factor of Cd (28.9%) and phytoextraction rates of all metals (17.4%, 48.6% and 104.6% for Cd, Zn and Cu, respectively), while the translocation factors had negligible difference between Lk9 inoculation (3.30, 0.50 and 0.40 for Cd, Zn and Cu, respectively) and non-inoculated control (2.95, 0.53 and 0.42 for Cd, Zn and Cu, respectively). It was also found that the symbiotic association between S. nigrum and Lk9 significantly increased the soil microbial biomass C by 39.2% and acid phosphatase activity by 28.6% compared to those in S. nigrum without Lk9. This study would provide a new insight into the bioaugmentation-assisted phytoextraction of heavy metal-contaminated soils.
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•Functional Pseudomonas sp. Lk9 enhanced Solanum nigrum extraction of Cd, Zn and Cu.•Lk9 inoculation improved soil Fe, P mineral nutrition supplies.•Lk9 inoculation enhanced soil Cd, Zn and Cu bioavailability.•Lk9 inoculation affected host-mediated low-molecular-weight organic acids secretion.•Lk9 is a good candidate for bioaugmentation-assisted metal phytoextraction.
Carcinoma-associated fibroblasts (CAFs) have been known to promote cancer progression by modifying the primary tumor microenvironment. We aimed to elucidate the intercellular communication between ...CAFs and secondary organs in salivary adenoid cystic carcinoma (SACC) metastasis.
Pre-metastatic and metastatic animal models of SACC were established using extracellular vesicles (EVs) from CAFs and SACC cells. Lung fibroblasts (LFs) were treated with EVs and their transcriptomic alterations were identified by RNA sequencing. ITRAQ were performed to analyze EV cargos. TC I-15 was used to inhibit EV uptake by LFs and SACC lung metastasis in vivo.
Here, we show that CAF EVs induced lung pre-metastatic niche formation in mice and consequently increased SACC lung metastasis. The pre-metastatic niche induced by CAF EVs was different from that induced by SACC EVs. CAF EVs presented a great ability for matrix remodeling and periostin is a potential biomarker characterizing the CAF EV-induced pre-metastatic niche. We found that lung fibroblast activation promoted by CAF EVs was a critical event at the pre-metastatic niche. Integrin α2β1 mediated CAF EV uptake by lung fibroblasts, and its blockage by TC I-15 prevented lung pre-metastatic niche formation and subsequent metastasis. Plasma EV integrin β1 was considerably upregulated in the mice bearing xenografts with high risk of lung metastasis.
We demonstrated that CAF EVs participated in the pre-metastatic niche formation in the lung. Plasma EV integrin β1 might be a promising biomarker to predict SACC metastasis at an early stage. An integrated strategy targeting both tumor and stromal cells is necessary to prevent SACC metastasis.
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