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Nanographenes, finite models of graphene sheets, are endowed with intriguing optical, electronic, and spintronic features. So-called heteroatom-doping, where one or more carbon is replaced by non-carbon light atoms has been proved effective in tuning the properties of nanographenes. Here we extend the concept of heteroatom nanographene doping to include metal centers. The method employed involves the use of a dipyrromethene fragment as an auxiliary ligand that is directly linked to the bay area of the model nanographene hexa-peri-hexabenzocoronene (HBC) to give a dipyrromethene-fused nanographene-type hybrid ligand (HBCP). HBCP has a corrole-like trianionic core that is capable of coordinating group 11 metal cations, including trivalent Cu, Ag and Au. These cations are introduced into the cavity with atomic precision to give metal complexes (HBCP-M; M = Cu, Ag, Au). The electronic structure and photophysical properties of HBCP and its metal complexes are investigated by steady-state and fs-transient spectroscopies, as well as DFT calculations. The ligand and metal complexes are also characterized via single crystal X-ray diffraction analyses. This work paves the way towards the precise metal doping of nanographenes within the carbon network, as opposed to the synthetic appendage of an independent chelating group, such as a fused tetrapyrrolic moiety. Nanographenes, finite models of graphene sheets, are endowed with intriguing optical, electronic, and spintronic features which can be tuned by replacing carbon via heteroatom-doping. Here the authors extend the concept of heteroatom nanographene doping to include metal centers.

Carbaporphyrin dimers, investigated for their distinctive electronic structures and exceptional properties, have predominantly consisted of systems containing identical subunits. This study addresses the associated knowledge gap by focusing on asymmetric carbaporphyrin dimers with Janus-like characteristics. The synthesis of a Janus-type carbaporphyrin pseudo-dimer 5 is presented. It displays antiaromatic characteristics on the fused side and nonaromatic behavior on the unfused side. A newly synthesized tetraphenylene (TPE) linked bis-dibenzihomoporphyrin 8 and a previously reported dibenzo[g,p]chrysene (DBC) linked bis-dicarbacorrole 9 were prepared as controls. Comprehensive analyses, including 1 H NMR spectral studies, single crystal X-ray diffraction analyses, and DFT calculations, validate the mixed character of 5 . A further feature of the Janus pseudo-dimer 5 is that it may be transformed into a heterometallic complex, with one side coordinating a Cu(III) center and the other stabilizing a BODIPY complex. This disparate regiochemical reactivity underscores the potential of carbaporphyrin dimers as versatile frameworks, with electronic features and site-specific coordination chemistry controlled through asymmetry. These findings position carbaporphyrin dimers as promising candidates for advances in electronic structure studies, coordination chemistry, materials science, and beyond. Carbaporphyrin dimers, known for their interesting photophysical properties and application in metal-organic chemistry, generally contain two identical subunits. Here, the authors highlight the benefits that can accrue from breaking the inherent symmetry of carbaporphyrin dimers and details a new approach to creating heterobimetallic complexes.

Bacterial wilt (BW) caused by Ralstonia solanacearum ( R. solanacearum ), is a vascular disease affecting diverse solanaceous crops and causing tremendous damage to crop production. However, our knowledge of the mechanism underlying its resistance or susceptibility is very limited. In this study, we characterized the physiological differences and compared the defense-related transcriptomes of two tobacco varieties, 4411-3 (highly resistant, HR) and K326 (moderately resistant, MR), after R. solanacearum infection at 0, 10, and 17 days after inoculation (dpi). A total of 3967 differentially expressed genes (DEGs) were identified between the HR and MR genotypes under mock condition at three time points, including1395 up-regulated genes in the HR genotype and 2640 up-regulated genes in the MR genotype. Also, 6,233 and 21,541 DEGs were induced in the HR and MR genotypes after R. solanacearum infection, respectively. Furthermore, GO and KEGG analyses revealed that DEGs in the HR genotype were related to the cell wall, starch and sucrose metabolism, glutathione metabolism, ABC transporters, endocytosis, glycerolipid metabolism, and glycerophospholipid metabolism. The defense-related genes generally showed genotype-specific regulation and expression differences after R. solanacearum infection. In addition, genes related to auxin and ABA were dramatically up-regulated in the HR genotype. The contents of auxin and ABA in the MR genotype were significantly higher than those in the HR genotype after R. solanacearum infection, providing insight into the defense mechanisms of tobacco. Altogether, these results clarify the physiological and transcriptional regulation of R. solanacearum resistance infection in tobacco, and improve our understanding of the molecular mechanism underlying the plant-pathogen interaction.

An endophytic bacterium Paenibacillus polymyxa DS-R5 which can effectively inhibit the growth of pathogenic fungi was isolated from Salvia miltiorrhiza in our previous study. By using hydrochloric acid precipitation, methanol extraction, silica gel column isolation, dextran gel chromatography column, and HPLC, 3 compounds with antifungal activity were isolated. To further improve the production of antifungal compounds produced by this strain, fermentation medium was optimized using one-factor-at-a-time, Plackett–Burman design, and Box–Behnken design experiments. Through statistical optimization, the optimal medium composition was determined to be as follows: 14.7 g/l sucrose, 20.0 g/l soluble starch, 7.0 g/l corn steep liquor, 10.0 g/l (NH4)2SO4, and 0.7 g/l KH2PO4. In this optimized medium, the highest titer of antifungal compounds reached 3452 U/ml, which was 123% higher than that in the initial medium. In addition, in order to guide scale-up for production, logistic and Luedeking–Piret equations were proposed to predict the cell growth and antifungal compounds production. The fermentation kinetics and empirical equations of the coefficients (X0, Xm, μm, α, and β) for the two models were reported, which will aid the design and optimization of industrial processes. The degrees of fit between calculated values of the model and the experimental data were 0.989 and 0.973, respectively. The results show that the cell growth and product synthesis models established in this study may better reflect the dynamic process of antifungal compounds production and provide a theoretical basis for further optimization and on-line monitoring of the fermentation process.

Hexaphyrins are one of the most studied expanded porphyrins that show intriguing electronic structure and coordination abilities in the past decades. However, core-modified hexaphyrins especially for benzene-replaced hexaphyrins are much less explored. Herein, we revisit the dibenzihexaphyrin system and demonstrate how to achieve the hexaphyrin-like organometallic nature of a benzene-replaced expanded porphyrin. For the “true” di- m -benzihexaphyrin 2 , metal complex with anticipated CCNN coordination is not realized probably due to the steric hindrance. Further, we synthesized an internally linked dibenzihexaphyrin ( 3 ) with a direct carbon–carbon bond between two phenylenes. As prepared, 3 has a strained biphenyl unit and can effectively coordinate two Cu(III) ions with CCNN coordination. This sharp contrast underscores the critical importance of the formed pre-organized corrole-like adj -CCNN cavities after linking two flanking phenylenes. 3 can also act as a bidentate ligand like traditional hexaphyrin, enabling the formation of an even more strained bis-Rh(I) complex. The electronic structures and photophysical properties of the free base and metal complexes are systematically studied by steady state absorption and fs-transient absorptions (fs-TA) spectroscopies, as well as DFT calculations. Notably, 3 can be regarded as a hexaphyrin-sized back-to-back fused bis-dicarbacorrole, which stands as the smallest fused carbaporphyrinoid array prepared to date.

A large amount of industrial and agricultural wastes are generated in the tobacco industry, such as tobacco steams, tobacco stalks, and tobacco leaves. How to increase the economic added value of industrial and agricultural wastes is an important issue. It is a promising value-added way that these biological wastes are recycled into carbon materials with excellent electrochemical properties. Herein, biochar were prepared from tobacco waste biomass (mainly tobacco stems, tobacco stalks and tobacco leaves) through one-step carbonization. The as-obtained biochar exhibited high specific capacitance of 305.92 F·g −1 (tobacco stems), 328.07 F·g −1 (tobacco stalks), and 272.48 F·g −1 (tobacco leaves) at 1 A·g −1 , when tested in a three-electrode system with 6 M KOH electrolyte. This study highlights the possibility of reusing tobacco waste to produce low-cost, green and high-performance carbon-based electrode materials for sustainable electrochemical energy storage systems.

A large amount of tobacco straw residues is produced around the world every year. These tobacco straw residues are usually incinerated or landfilled directly, which cause environmental pollution and waste of resources. Therefore, it is necessary to find a green way to recycle these tobacco straw residues. Converting tobacco straw residues into biomass carbon materials for supercapacitor electrode materials is an appropriate way. In this study, tobacco straw core carbon (TSC) was obtained from tobacco straw core waste, which was carbonized directly in the tube furnace without N 2 . The tobacco straw core carbon had a higher specific surface area because of the self-activation of the H 2 O and CO 2 in the carbonization. A variety of analytical instruments were used to characterize the prepared porous carbon. Herein, this work can provide new ideas for energy materials, and solve the problem of the disposal of tobacco straw residues. What’s more, it also can provide a sustainable development opportunity for tobacco farmers to alleviate poverty, dig potential and transform.

The tumor suppressor TP53 is the most frequently mutated gene in human cancers. Mutant p53 (mutp53) proteins often accumulate to very high levels in human cancers to promote cancer progression through the gain-of-function (GOF) mechanism. Currently, the mechanism underlying mutp53 accumulation and GOF is incompletely understood. Here, we identified TRIM21 as a critical E3 ubiquitin ligase of mutp53 by screening for specific mutp53-interacting proteins. TRIM21 directly interacted with mutp53 but not WT p53, resulting in ubiquitination and degradation of mutp53 to suppress mutp53 GOF in tumorigenesis. TRIM21 deficiency in cancer cells promoted mutp53 accumulation and GOF in tumorigenesis. Compared with p53R172H knockin mice, which displayed mutp53 accumulation specifically in tumors but not normal tissues, TRIM21 deletion in p53R172H knockin mice resulted in mutp53 accumulation in normal tissues, an earlier tumor onset, and a shortened life span of mice. Furthermore, TRIM21 was frequently downregulated in some human cancers, including colorectal and breast cancers, and low TRIM21 expression was associated with poor prognosis in patients with cancers carrying mutp53. Our results revealed a critical mechanism underlying mutp53 accumulation in cancers and also uncovered an important tumor-suppressive function of TRIM21 and its mechanism in cancers carrying mutp53.

The Kalman filter is an important technique for system state estimation. It requires the exact knowledge of system noise statistics to achieve optimal state estimation. However, in practice, this knowledge is often unknown or inaccurate due to uncertainties and disturbances involved in the dynamic environment, leading to degraded or even divergent filtering solutions. To address this issue, this paper presents a new method by combining the random weighting concept with the limited memory technique to accurately estimate system noise statistics. To avoid the influence of excessive historical information on state estimation, random weighting theories are established based on the limited memory technique to estimate both process noise and measurement noise statistics within a limited memory. Subsequently, the estimated system noise statistics are fed back into the Kalman filtering process for system state estimation. The proposed method improves the Kalman filtering accuracy by adaptively adjusting the weights of system noise statistics within a limited memory to suppress the interference of system noise on system state estimation. Simulations and experiments as well as comparison analysis were conducted, demonstrating that the proposed method can overcome the disadvantage of the traditional limited memory filter, leading to im-proved accuracy for system state estimation.

Background High-risk human papilloma virus (hrHPV) is the main causal factor of cervical precancer and cancer when persistent infection is left untreated. Previous studies have confirmed the vaginal microbiota is associated with HPV infection and the development of cervical lesions. The microbiota at different parts of the female genital tract is closely related but different from each other. To analyze the distinction between the vaginal and cervical microbiota of hrHPV(+) women in China, one hundred subjects were recruited, including 10 patients with HPV16/18(+) and cervical carcinoma, 38 patients with HPV16/18(+) but no cervical carcinoma, 32 patients with other hrHPV(+) and 20 healthy controls with HPV(−). Vaginal and cervical microbiota were separately tested through next-generation sequencing (NGS) targeting the variable region (V3-V4) of the bacterial ribosome 16S rRNA gene. Results HrHPV(+) subjects had higher percentages of vaginal douching history ( P  = 0.001), showed more frequent usage of sanitary pads ( P  = 0.007), had more sex partners ( P  = 0.047), were more sexually active ( P  = 0.025) and more diversed in ways of contraception ( P  = 0.001). The alpha diversity of the cervical microbiota was higher than that of the vagina. The cervical microbiota consisted of a lower percentage of Firmicutes and a higher percentage of Proteobacteria than the vagina at the phylum level. Sphingomonas , belonging to α- Proteobacteria, was almost below the detection limit in the vagina but accounted for five to 10 % of the bacteria in the hrHPV(−) cervix ( P <0.001) and was inversely associated with hrHPV infection ( P <0.05). Pseudomonas , belonging to γ- Proteobacteria, could hardly be seen in the normal vagina and shared a small percentage in the normal cervix but was significantly higher in the HPV16/18(+) ( P <0.001) and cancerous cervix ( P <0.05). No significant difference was shown in the percentage of BV associated anaerobes, like Gardnerella , Prevotella , Atopobium and Sneathia , between the cevix and vigina. Conclusions The proportion of Proteobacteria was significantly higher in the cervical microbiota than that of vagina. The hrHPV infection and cervical cancer was positively associated with Pseudomonas and negatively associated with Sphingomonas . It is of great improtance to deeply explore the cervical microbiota and its function in cervical cacinogenesis.