Metal-Ion Coupling in Metal-Organic Framework Materials Regulating the Output Performance of a Triboelectric Nanogenerator.

Metal-organic frameworks (MOFs) as friction nanopower generation materials have attracted more and more research and attention because of the inherent three-dimensional framework structure and large aperture. In this work, the ZUT-75(Mn) with a one-dimensional pore structure was synthesized by using electron-rich benzimidazole carboxylic acid ligands, and isomorphic offspring MOF materials were obtained by single crystal-single crystal solvent-assisted metal-ion exchange. The exchange process was monitored by liquid UV-vis spectroscopy, atomic absorption spectrometry, and energy-dispersive X-ray spectroscopy. The metal-oxygen coordination energy, X-ray photoelectron spectroscopy binding energy, and hard-soft acid-base principle verified the spontaneity of the central-metal-exchange reaction. The four materials were applied to a triboelectric nanogenerator (TENG), and the output performance law of ZUT-75 was Co-MT > Zn-MT > Cu-MT > Mn-MT. Among them, the charge and power densities of Co-MT were up to 127.05 µC m-2 and 3280.50 mW m-2. When the density functional theory calculation and variable-temperature magnetic susceptibility test results were combined, it was concluded that low metal-ion-coupling degree promoted the formation and transfer of contact electrifications, which greatly improved the output performance of the TENG. This work provided a new idea for improving the output performance of the TENG.

A Double-Helix Metal-Chain Metal-Organic Framework as a High-Output Triboelectric Nanogenerator Material for Self-Powered Anticorrosion.

The development of novel metal organic framework (MOF) friction power generation materials with high stability is important. This paper reports the first example of a double-helix metal chain organic framework with a network structure (ZUT-8). ZUT-8 shows high chemical stability, functional adjustability, and excellent output performance of friction power generation, which is superior to traditional coordination polymer materials. The cathodic protection system with ZUT-8 can prevent metal corrosion significantly. The output performance can be improved effectively by enhancing the conjugate effect of the linker. The theoretical calculation results showed that an increase in the degree of conjugation could significantly reduce the band gap, thereby affecting the friction power output signal. This study opens the door to constructing MOF materials with a double-helix metal chain and will promote their potential applications in self-powered electrochemical cathodic protection.

Facile synthesis of Fe3O4@Au core-shell nanocomposite as a recyclable magnetic surface enhanced Raman scattering substrate for thiram detection.

The Fe3O4@Au core-shell nanocomposites, as the multifunctional magnetic surface enhanced Raman scattering (SERS) substrates, were fabricated successfully by the seeds growth method based on the Fe3O4-Au core-satellite nanocomposites. The SERS properties of the Fe3O4-Au core-satellite nanocomposites and the Fe3O4@Au core-shell nanocomposites were compared using 4-aminothiophenol (4-ATP) as the probe molecule. It was found that Fe3O4@Au core-shell nanocomposites showed better SERS performance than Fe3O4-Au core-satellite nanocomposites. The Au shell provided an effectively large surface area for forming sufficient plasmonic hot spots and capturing target molecules. The integration of magnetic core and plasmonic Au nanocrystals endowed the Fe3O4@Au core-shell nanocomposites with highly efficient magnetic separation and enrichment ability and abundant interparticle hot spots. The Fe3O4@Au core-shell nanocomposites could be easily recycled because of the intrinsic magnetism of the Fe3O4 cores and had good reproducibility of the SERS signals. For practical application, the Fe3O4@Au core-shell nanocomposites were also used to detect thiram. There was a good linear relationship between the SERS signal intensity and the concentration of thiram from 1 × 10-3 to 1 × 10-8 M and the limit of detection was 7.69 × 10-9 M. Moreover, residual thiram on apple peel was extracted and detected with a recovery rate range of 99.3%. The resulting substrate with high SERS activity, stability and strong magnetic responsivity makes the Fe3O4@Au core-shell nanocomposites a perfect choice for practical SERS detection applications.

A maize ADP-ribosylation factor ZmArf2 increases organ and seed size by promoting cell expansion in Arabidopsis.

ADP-ribosylation factors (ARFs) are small GTP-binding proteins that regulate a wide variety of cell functions. Previously, we isolated a new ARF, ZmArf2, from maize (Zea mays). Sequence and expression characteristics indicated that ZmArf2 might play a critical role in the early stages of endosperm development. In this study, we investigated ZmArf2 function by analysis of its GTP-binding activity and subcellular localization. We also over-expressed ZmArf2 in Arabidopsis and measured organ and cell size and counted cell numbers. The expression levels of five organ size-associated genes were also determined in 35S::ZmArf2 transgenic and wild-type plants. Results showed that the recombinant ZmArf2 protein purified from Escherichia coli exhibited GTP-binding activity. Subcellular localization revealed that ZmArf2 was localized in the cytoplasm and plasma membrane. ZmArf2 over-expression in Arabidopsis showed that 35S::ZmArf2 transgenic plants were taller and had larger leaves and seeds compared to wild-type plants, which resulted from cell expansions, not an increase in cell numbers. In addition, three cell expansion-related genes, AtEXP3, AtEXP5 and AtEXP10, were upregulated in 35S::ZmArf2 transgenic lines, while the expression levels of AtGIF1 and AtGRF5, were unchanged. Collectively, our studies suggest that ZmArf2 has an active GTP-binding function, and plays a crucial role in growth and development in Arabidopsis through cell expansion mediated by cell expansion genes.

Will the Construction of Sports Facilities Nudge People to Participate in Physical Exercises in China? The Moderating Role of Mental Health.

This study aims to examine the nudging effect of the sports facility construction on physical exercise (PE) participation with consideration of the moderating role of mental health in China. Multiple linear regression models are used in this study. The subjects are 4634 from the 2014 China Family Panel Studies (CFPS) data, which is a nationally representative longitudinal survey of Chinese individuals. We find that the construction of sports facilities nudges people to participate in PE, and gender, age, and education significantly influence people's participation in PE. Young, female, and better-educated people compose the "neo-vulnerable" population, who participate less in PE in China and need more interventions. Mental health status has no significant effect on people's PE participation, while it negatively moderates the nudging effect of the construction of sports facilities on PE. The results of this study suggest that only building sporting facilities is insufficient to encourage PE participation. Policies and interventions should be given to mentally disturbed individuals to guarantee and magnify the nudging effect of sports facilities on PE.

3D nanocrystalline metal-organic framework materials for the improved output performance of triboelectric nanogenerators.

Triboelectric nanogenerators (TENGs) based on contact electrification and electrostatic induction can effectively convert low-frequency mechanical energy into electrical energy and has attracted considerable attention. However, the low current output performance seriously hinders the wide application of TENGs. Herein, a 3D nanocrystalline metal-organic framework (Cd-MOF) with a specific structure and morphology was reasonably designed as a high-performance triboelectric positive electrode material. The triboelectric test results showed that the maximum instantaneous short-circuit current of Cd-MT was 55.32 µA and the stable output performance maintained a long-term continuous operation for 10 000 s. The peak values of the charge density and electric power density were 102.39 µC m-2 and 2451.04 mW m-2, respectively. In addition, the Cd-MT could quickly fully charge commercial capacitors and light a large number of LED lamps. This work provides a new idea for the development and design of functional MOF triboelectric materials.

Cloud platform to improve efficiency and coverage of asynchronous multidisciplinary team meetings for patients with digestive tract cancer.

Background: Multidisciplinary team (MDT) meetings are the gold standard of cancer treatment. However, the limited participation of multiple medical experts and the low frequency of MDT meetings reduce the efficiency and coverage rate of MDTs. Herein, we retrospectively report the results of an asynchronous MDT based on a cloud platform (cMDT) to improve the efficiency and coverage rate of MDT meetings for digestive tract cancer. Methods: The participants and cMDT processes associated with digestive tract cancer were discussed using a cloud platform. Software programming and cMDT test runs were subsequently conducted to further improve the software and processing. cMDT for digestive tract cancer was officially launched in June 2019. The doctor response duration, cMDT time, MDT coverage rate, National Comprehensive Cancer Network guidelines compliance rate for patients with stage III rectal cancer, and uniformity rate of medical experts' opinions were collected. Results: The final cMDT software and processes used were determined. Among the 7462 digestive tract cancer patients, 3143 (control group) were diagnosed between March 2016 and February 2019, and 4319 (cMDT group) were diagnosed between June 2019 and May 2022. The average number of doctors participating in each cMDT was 3.26 ± 0.88. The average doctor response time was 27.21 ± 20.40 hours, and the average duration of cMDT was 7.68 ± 1.47 min. The coverage rates were 47.85% (1504/3143) and 79.99% (3455/4319) in the control and cMDT groups, respectively. The National Comprehensive Cancer Network guidelines compliance rates for stage III rectal cancer patients were 68.42% and 90.55% in the control and cMDT groups, respectively. The uniformity rate of medical experts' opinions was 89.75% (3101/3455), and 8.97% (310/3455) of patients needed online discussion through WeChat; only 1.28% (44/3455) of patients needed face-to-face discussion with the cMDT group members. Conclusion: A cMDT can increase the coverage rate of MDTs and the compliance rate with National Comprehensive Cancer Network guidelines for stage III rectal cancer. The uniformity rate of the medical experts' opinions was high in the cMDT group, and it reduced contact between medical experts during the COVID-19 pandemic.

Semaphorin-3A guides radial migration of cortical neurons during development.

Postmitotic neurons in the developing cortex migrate along radial glial fibers to their proper location in the cortical plate and form the layered structure. Here we report that the radial migration of rat layer II/III cortical neurons requires guidance by the extracellular diffusible factor Semaphorin-3A (Sema3A). This factor is expressed in a descending gradient across the cortical layers, whereas its receptor neuropilin-1 (NP1) is highly expressed in migrating neurons. Downregulation or conditional knockout of NP1 in newborn cortical neurons impedes their radial migration by disrupting their radial orientation during migration without altering their cell fate. Studies in cultured cortical slices further show that the endogenous gradient of Sema3A is required for the proper migration of newborn neurons. In addition, transwell chemotaxis assays show that isolated newborn neurons are attracted by Sema3A. Thus, Sema3A may function as a chemoattractive guidance signal for the radial migration of newborn cortical neurons toward upper layers.

Effect of gigantol on the proliferation of hepatocellular carcinoma cells tested by a network-based pharmacological approach and experiments.

BACKGROUND: Hepatocellular carcinoma (HCC) is a common clinical malignant disease and the second leading cause of cancer-related death worldwide. Dendrobium is a commonly applied nourishing drug in traditional Chinese medicine. Gigantol is a phenolic compound extracted from Dendrobium. The compound has attracted attention for its anticancer effects. However, the mechanism of gigantol in HCC has not been extensively explored. METHODS: Potential targets of gigantol were predicted by SwissTargetPrediction. HCC-related genes were obtained from the GeneCards, Online Mendelian Inheritance in Man (OMIM), Pharmacogenetics and Pharmacogenomics Knowledge Base (PharmGKB), Therapeutic Target Database (TTD) and DrugBank databases. The "gigantol-target-disease" network was constructed using Cytoscape software. Protein interaction network analysis was performed using STRING software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were executed utilizing the R package to explore the possible regulatory mechanisms of gigantol in HCC. To authenticate the role of gigantol in HCC, Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, wound healing assay, Matrigel invasion assay and Western blot were performed. RESULTS: Three core genes were screened from 32 closely linked genes. Pathway analysis yielded many signaling pathways associated with cancer. The CCK-8 assay and EdU assay indicated that gigantol suppressed the growth of HCC cells. The wound healing assay and Matrigel invasion assay showed the inhibition of migration and metastasis of HCC cells by gigantol. We verified from molecular docking and protein level that gigantol can exert regulatory effects through three targets, ESR1, XIAP and HSP90AA1. Furthermore, Western blot results tentatively revealed that gigantol may inhibit HCC progression through the HSP90/Akt/CDK1 pathway. CONCLUSIONS: Our results confirms anti-HCC proliferation activity of gigantol through PI3K pathway described in existing literature by different experimental approaches. Furthermore, it has discovered other proteins regulated by the drug that was not previously reported in the literature.These findings provide potential molecular and cellular evidence that gigantol may be a promising antitumor agent.

Nestin is essential for mitogen-stimulated proliferation of neural progenitor cells.

The intermediate filament (IF) protein nestin is a widely accepted molecular marker for neural progenitor cells (NPCs), but its function during neurogenesis remains largely unknown. We found that in embryonic cortical NPCs down-regulation of the expression of nestin, but not its co-polymer IF protein vimentin, resulted in a G1 cell-cycle arrest and a severe reduction in the generation of neurons. Furthermore, down-regulating nestin expression in cultured cortical NPCs markedly suppressed their colony-formation ability and blocked the elevation of the cyclin D1/E protein level in response to the treatment with bFGF. Interestingly, nestin down-regulation caused a marked suppression in the activation of the phosphoinositide 3-kinase (PI3K) pathway but not the mitogen-activated protein kinase (MAPK) pathway in these NPCs. Moreover, defects in the proliferation of cortical NPCs caused by nestin down-regulation could be prevented by up-regulating PI3K activity. Thus, nestin is essential for the proliferation of NPCs by promoting the activation of PI3K in response to mitogenic growth factors.

Foliar Application of Silicon Enhances Resistance Against Phytophthora infestans Through the ET/JA- and NPR1- Dependent Signaling Pathways in Potato.

Late blight (LB), caused by the oomycete pathogen Phytophthora infestans, is a devastating disease of potato that is necessary to control by regularly treatment with fungicides. Silicon (Si) has been used to enhance plant resistance against a broad range of bacterial and fungal pathogens; however, the enhanced LB resistance and the molecular mechanisms involving the plant hormone pathways remain unclear. In this study, Si treatment of potato plants was found to enhance LB resistance in both detached leaves and living plants accompanied by induction of reactive oxygen species (ROS) production and pathogenesis-related genes expression. Regarding the hormone pathways involved in Si-mediated LB resistance, we found a rapidly increased content of ethylene (ET) 15 min after spraying with Si. Increased jasmonic acid (JA) and JA-Ile and decreased salicylic acid (SA) were identified in plants at 1 day after spraying with Si and an additional 1 day after P. infestans EC1 infection. Furthermore, pretreatment with Me-JA enhanced resistance to EC1, while pretreatment with DIECA, an inhibitor of JA synthesis, enhanced the susceptibility and attenuated the Si-mediated resistance to LB. Consistent with these hormonal alterations, Si-mediated LB resistance was significantly attenuated in StETR1-, StEIN2-, StAOS-, StOPR3-, StNPR1-, and StHSP90-repressed plants but not in StCOI1- and StSID2-repressed plants using virus-induced gene silencing (VIGS). The Si-mediated accumulation of JA/JA-Ile was significantly attenuated in StETR1-, StEIN2-, StOPR3- and StHSP90-VIGS plants but not in StCOI1-, StSID2- and StNPR1-VIGS plants. Overall, we reveal that Si can be used as a putative alternative to fungicides to control LB, and conclude that Si-mediated LB resistance is dependent on the ET/JA-signaling pathways in a StHSP90- and StNPR1-dependent manner.

Copper ions suppress abscisic acid biosynthesis to enhance defence against Phytophthora infestans in potato.

Copper-based antimicrobial compounds are widely and historically used to control plant diseases, such as late blight caused by Phytophthora infestans, which seriously affects the yield and quality of potato. We previously identified that copper ion (Cu2+ ) acts as an extremely sensitive elicitor to induce ethylene (ET)-dependent immunity in Arabidopsis. Here, we found that Cu2+ induces the defence response to P. infestans in potato. Cu2+ suppresses the transcription of the abscisic acid (ABA) biosynthetic genes StABA1 and StNCED1, resulting in decreased ABA content. Treatment with ABA or inhibitor fluridone made potato more susceptible or resistance to late blight, respectively. In addition, potato with knockdown of StABA1 or StNCED1 showed greater resistance to late blight, suggesting that ABA negatively regulates potato resistance to P. infestans. Cu2+ also promotes the rapid biosynthesis of ET. Potato plants treated with 1-aminocyclopropane-1-carboxylate showed enhanced resistance to late blight. Repressed expression of StEIN2 or StEIN3 resulted in enhanced transcription of StABA1 and StNCED1, accumulation of ABA and susceptibility to P. infestans. Consistently, StEIN3 directly binds to the promoter regions of StABA1 and StNCED1. Overall, we concluded that Cu2+ triggers the defence response to potato late blight by activating ET biosynthesis to inhibit the biosynthesis of ABA.

[Identification and phylogenetic analysis on the aroA gene of Haemophilus parasuis].

OBJECTIVE: We clarified the genetic structure and phylogenetic relationship of the aroA gene in Haemophilus parasuis, a gene encoding 5'-enolpyruvylshikimate-3-phosphate synthetase. METHODS: We used PCR and bacterial genome walking techniques to determine the aroA gene locus in the genome of H. parasuis serovar 5. Then we sequenced the aroA gene of H. parasuis reference strains and local isolates. All aroA gene sequences from H. parasuis, other members of the family Pasteurellaceae, Escherichia coli and Salmonella typhimurium were analyzed for phylogenetic relationship. RESULTS: An approximately 3.7 kb fragment containing the whole aroA gene was obtained from the genomic DNA of H. parasuis serovar 5. Sequence analysis showed that the size of the whole aroA gene was 1314 bp, encoding a 437 aa product with molecular weight 47.9 kDa. The sequence immediately upstream of the aroA gene shared high similarity with phosphoenolpyruvate carboxylase gene. The whole aroA gene fragment could be amplified from all strains of H. parasuis serovars with a size of 1476 bp. The nucleotide sequence similarity was above 97.7% in H. parasuis serovars. The similarity was 70.6%-78.9% between H. parasuis serovar 5 and other members of Pasteurellaceae. The similarity between H. parasuis serovar 5 and E. coli or S. typhimurium was 66.4% and 67.2% respectively. CONCLUSION: No obvious difference was found in the aroA gene sequence of H. parasuis reference strains (15 serovars) and 3 local isolates. The nucleotide sequence of the aroA gene was well-conserved within Gram-negative organisms.

Mutation on N-terminus of polyhydroxybutyrate synthase of Ralstonia eutropha enhanced PHB accumulation.

Polyhydroxyalkanoate (PHA) synthase is the central enzyme involved in the biosynthesis of PHA, a family of bacterial biodegradable polyesters. Due to its high variability, the N-terminal fragment of this enzyme was previously considered as unnecessary for a functionally active enzyme. In this study, polyhydroxybutyrate synthase from Ralstonia eutropha (PhbC(Re)) with a deletion on N-terminal 88 amino acid residues showed a significant reduced activity, as reflected by only 1.5% PHB accumulation compared with the wild type which produced 58.4% PHB of the cell dry weight. Whilst several site-specific mutagenesis results revealed the amphiphilic alpha-helix assembled by the amino acid region, D70-E88 played an important role in both maintaining the PHB synthase activity and regulating molecular weight and polydispersity of accumulated PHB homopolymer.