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NAP (NAC-like, Activated by APETALA3/PISTILLATA) is a subfamily of the transcription factor NAC gene family, which is widely involved in regulating plant growth and development, leaf senescence, and response to hormones and abiotic stress. Firstly, the NAP subfamily members were identified from the genomic database of Saccharum spontaneum, and phylogenetic analysis, conserved domains, and cis-regulatory elements were predicted using comparative genomics and various bioinformatics methods. Secondly, the allele SsNAP2a of the SsNAP2 member was isolated from the cDNA library of a wide accession SES208. The relative expression characteristics of the SsNAP2a were detected by qRT-PCR under hormone and abiotic stresses at different growth and development stages. Finally, transient overexpression and subcellular localization performed the function of SsNAP2a gene. The results showed that five NAP subfamily members were identified in the genome of S. spontaneum. The subcellular localization predicted that the encoded proteins of all members were localized in the nucleus. The Ka/Ks ratio of five gene pairs was less than 1, indicating that purifying selection was crucial in the evolution. Phylogenetic analysis revealed that 46 NAP members, including five representative angiosperms (Arabidopsis thaliana, Ananas comosus, Oryza sativa, Zea mays, and Sorghum bicolor), 12 reported species, and the S. spontaneum, were classified into four Clades. The evolution order was Clade I > Clade II > Clade III > Clade IV. In addition, the promoter regions of SsNAP members predicted many cis-acting elements in response to abscisic acid, jasmonic acid, low temperature, and other stresses. We speculated that they were involved in various hormone and abiotic stress-related response pathways. Furthermore, the full-length cDNA sequence of the SsNAP2a gene (GenBank accession number: OQ335094) was isolated from the wild accession SES208, with an open reading frame of 1173 bp and encoding 390 amino acid residues. The amino acid sequence similarity between SsNAP2 and SsNAP2a proteins was 97.70%. There was a difference of 10 amino acid residues, indicating that the autopolyploid allelic sequences of Saccharum species were significant difference. The qRT-PCR demonstrated that the SsNAP2a gene was constitutively expressed in various tissues of S. spontaneum, especially in the senescent bark and root, and its expression level was significantly induced under the treatment of ethylene, ET, abscisic acid (ABA), low temperature at 4, and high temperature at 40 . However, the relative expression level of the SsNAP2a gene was significantly down-regulated under 8% polyethylene glycol (PEG) stress. Subcellular localization revealed that the SsNAP2a-GFP fusion protein was located in the cell nucleus of Nicotiana benthamiana leaves. After transient overexpression of the SsNAP2a gene for seven days, the leaves of N. benthamiana displayed obvious curling and shriveling phenotype. The relative expression level of ET synthesis-related genes (NtEFE26, NtAccdeaminase) was significantly up-regulated, while salicylic acid, jasmonic acid, and ABA synthesis-related genes (NtPR-1a/c, NtPR3, and NtAREB1) were significantly down-regulated, indicating that the SsNAP2a gene was involved in multiple hormone signaling pathways to induce leaf senescence. These results lay a foundation for exploring the biological functions of NAP subfamily gene members involved in sugarcane leaf senescence and provide candidate gene resources for breeding anti-senescence new cultivars. [ABSTRACT FROM AUTHOR]

The dynamic properties of the flow induced by a dielectric barrier discharge (DBD) plasma actuator array are investigated from the Lagrangian perspective. First, numerical simulations based on a body force model are performed to obtain the flow field induced by unsteady plasma actuation in the burst mode. The numerical simulations capture the flow characteristics of plasma actuation well. Subsequently, the ridges of the finite-time Lyapunov exponent field are employed to identify the Lagrangian coherent structures (LCSs). Both the attracting and repelling LCSs organize the plasma-induced flow's dynamic behaviors. The attracting LCSs visualize the plasma-induced vortices. The vortex formation, development, and merging processes in the unsteady plasma actuation are resolved well by the LCSs. The material transport in the plasma-induced flow is analyzed by tracing the fluid particle motions. Then, the influences of the actuation parameters, duty cycle, and burst frequency on the flow structures are explored via the attracting LCSs. The presented results enhance the understanding of plasma actuation flow physics and promote the optimal use of DBD plasma actuator arrays. [ABSTRACT FROM AUTHOR]

Ag2Te nanowires with a diameter of approximately 200 nm and a length of several micrometers were prepared using a simple one-step solvothermal method without templates and surfactants. Ag(NO)3 and Na2TeO3 were used as the Ag and Te sources, respectively, and N2H4·H2O was used as the reducing agent. Based on the study of the morphology and composition of the Ag2Te nanowires obtained under different hydrothermal conditions, a possible formation mechanism of Ag2Te nanowires was proposed. An Ag-rich Ag2Te sample was prepared by adjusting the molar ratio of Ag and Te. Furthermore, Ag2Te nanowire powders were condensed to bulk materials by spark plasma sintering at 673 K for 5 min. The thermoelectric properties of the Ag2Te bulk materials were measured between 323 K and 673 K. The phase transition temperature of the transformation from α-Ag2Te to β-Ag2Te was determined to be 419 K by differential scanning calorimetry. The highest ZT values of pure Ag2Te and Ag self-doped Ag2Te bulk samples reached 0.9 and 1.1 at 623 K, respectively. These results indicate that this one-pot technique for preparing the Ag self-doped Ag2Te sample with enhanced thermoelectric performance may be widely used in other thermoelectric systems that can be fabricated by solution methods. [ABSTRACT FROM AUTHOR]

Bismuth sulfide is a promising thermoelectric material because of its low cost and toxicity; however, its low electrical conductivity limits its thermoelectric properties. In this study, Bi 2 S 3 +x wt% HfCl 4 (x = 0, 0.25, 0.5, 0.75, and 1.0) bulk samples are fabricated using a combination of melting and spark plasma sintering. The microstructures, electronic structures, and thermoelectric properties of the composites are characterized. The results of electronic structure calculations show that doping with HfCl 4 produces an impurity energy level that narrows the bandgap and allows the Fermi energy level to enter the conduction band, leading to a favorable increase in carrier concentration. By regulating the HfCl 4 doping concentration, the electrical conductivity of the 0.75 wt% doped sample reaches 253 Scm -1 at 423 K and its maximum ZT value is 0.47 at 673 K. Moreover, the sample is compounded with Bi 2 S 3 nanorods prepared by the hydrothermal method, reducing thermal conductivity by 30% due to the introduction of additional interfaces and pores. This resulted in a final ZT value of 0.61 at 673 K, which is approximately eight times higher than that of pure Bi 2 S 3 . This step-by-step optimization approach provides a valuable methodology for enhancing the performance of other thermoelectric material systems., (© 2023 Wiley‐VCH GmbH.)

Background: Heat shock 70kDa protein 5 (HSPA5), also known as GRP78, is widely expressed in most malignant cells and has been shown to have a significant role in the spread of most malignancies by transferring them to the cell membrane. High-level HSPA5 may serve as an independent prognostic marker for various malignancies due to its ability to accelerate tumor growth and migration, inhibit cell apoptosis and closely connect to prognosis. Therefore, it is crucial to examine HSPA5 using pan-cancer research, which might result in the discovery of novel cancer treatment targets., Method: The GTEx and TCGA databases have both provided evidence of the expression of various amounts of HSPA5 in various tissues. The Clinical Proteomics Tumor Analysis Consortium (CPTAC) evaluated the levels of HSPA5 protein expression, while qPCR investigations also evaluated the expression of HSPA5 mRNA in certain tumors. HSPA5 was studied using the Kaplan-Meier method to examine how it influences overall survival and disease-free survival in malignancies. GEPIA2 was used to investigate the correlation between HSPA5 expression and the clinical stage of cancer. The tumor-immune system interaction database (TISIDB) examined the expression of HSPA5 in association with molecular and tumor immune subtypes. The co-expressed genes of HSPA5 were extracted from the STRING database, and the top 5 co-expressed genes of HSPA5 in 33 cancers were identified using the TIMER database. Further research examined the relationship between tumor mutations and HSPA5. Microsatellite Instability (MSI) and Tumor Mutation Burden (TMB) were the primary areas of interest. The association between HSPA5 mRNA expression and immune infiltration was also explored using the TIMER database. Additionally, through the Linkedomics database, we examined the enrichment of GO and KEGG for HSPA5 in glioblastoma. Finally, the Cluster Analyzer tool was used to carry out a GSEA functional enrichment investigation., Results: HSPA5 mRNA expression was found to be greater in all 23 tumor tissues than in the equivalent normal tissues, and high HSPA5 expression appeared to be strongly related to a poor prognosis in the majority of cancers, as observed by survival plots. In the tumour clinical stage display map, HSPA5 showed differential expression in most tumours. HSPA5 is strongly associated with Tumor Mutation Burden (TMB) and Microsatellite Instability (MSI). Cancer-associated Fibroblasts (CAFs) infiltration was strongly associated with HSPA5, as were nine immunological subtypes of malignancy and seven molecular subtypes of malignancy. According to the results of GO and KEGG enrichment analyses, HSPA5 in GBM is mostly involved in neutrophil-mediated immunological and collagen metabolic activities. Additionally, GSEA enrichment analyses of HSPA5 and associated genes demonstrated a substantial link between HSPA5 and the immunological milieu of tumors, cell division and nervous system regulation. By using qPCR, we were able to further corroborate the enhanced expression in the GBM, COAD, LUAD and CESC cell lines., Conclusion: Our bioinformatics research leads us to hypothesize that HSPA5 may be involved in immune infiltration as well as tumor growth and progression. Additionally, it was found that differentially expressed HSPA5 is linked to a poor prognosis for cancer, with the neurological system, the tumor immunological microenvironment and cytokinesis being potential contributing factors. As a result, HSPA5 mRNA and the associated protein might be used as therapeutic targets and possible prognostic markers for a range of malignancies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)