A general and efficient organocatalytic asymmetric polymerization approach for the synthesis of chiral covalent organic frameworks (CCOFs) has been developed. With a chiral 2‐methylpyrrolidine ...catalyst, a series of tris(N‐salicylideneamine)‐derived β‐ketoenamine‐CCOFs are directly constructed from prochiral aldehyde‐ and primary amine‐monomers. The adopted aminocatalytic asymmetric Schiff‐base condensation herein is performed under ambient conditions with clear green synthetic advantages over the conventional acid‐catalysed solvothermal methods. The obtained β‐ketoenamine‐CCOFs can be further metalated by a solid‐state coordination approach, and the resulting CuII@CCOFs can highly promote an asymmetric A3‐coupling reaction. Specifically, a CuII@CCOF@chitosan aerogel was fabricated as a highly efficient fixed‐bed model reactor for scaled‐up catalysis. The concept of aminocatalytic asymmetric polymerization might open a new way for constructing the CCOFs via asymmetric organocatalysis.
A new and general organocatalytic asymmetric polymerization approach for the chiral covalent organic framework (CCOF) synthesis under ambient conditions is presented. The metalated CCOF can be further shaped into a fixed‐bed reactor by incorporation with ecofriendly and low‐cost chitosan to realize the scaled‐up catalytic asymmetric A3‐coupling reaction in a green and facile way.
In mammalians and yeast, the splicing factor U2AF65/Mud2p functions in precursor messenger RNA (pre-mRNA) processing. Arabidopsis AtU2AF65b encodes a putative U2AF65 but its specific functions in ...plants are unknown. This paper examines the function of AtU2AF65b as a negative regulator of flowering time in Arabidopsis.
We investigated the expression and function of AtU2AF65b in abscisic acid (ABA)-regulated flowering as well as the transcript abundance and pre-mRNA splicing of flowering-related genes in the knock-out mutants of AtU2AF65b.
The atu2af65b mutants show early-flowering phenotype under both long-day and short-day conditions. The transcript accumulation of the flowering repressor gene FLOWERING LOCUS C (FLC) is reduced in the shoot apex of atu2af65b, due to both increased intron retention and reduced transcription activation. Reduced transcription of FLC results, at least partially, from the abnormal splicing and reduced transcript abundance of ABSCISIC ACID-INSENSITIVE 5 (ABI5), which encodes an activator of FLC in ABA-regulated flowering signaling. Additionally, the expression of AtU2AF65b is promoted by ABA. Transition to flowering and splicing of FLC and ABI5 in the atu2af65b mutants are compromised during ABA-induced flowering.
ABA-responsive AtU2AF65b functions in the pre-mRNA splicing of FLC and ABI5 in shoot apex, whereby AtU2AF65b is involved in ABA-mediated flowering transition in Arabidopsis.
As education advances with the times, traditional English EFL teaching can no longer fully adapt to the current educational situation. This paper studies the mining of the Civics element in English ...teaching integrates it into EFL classroom teaching, and constructs the morality cultivation EFL critical thinking ability teaching strategy based on the critical thinking ability model. The effects of applying this teaching strategy are analyzed and compared to the six dimensions of critical thinking ability: interpretation, analysis, evaluation, reasoning, explanation, and self-regulation ability. The exploration of critical thinking ability development and individual teacher factors is conducted. After the teaching experiment, the experimental group improved by 12.08 points, while the control group only improved by 0.46 points, indicating a significant difference between the two groups’ scores. The Sig. The values of the experimental group in the six dimensions are less than 0.05, and the Sig. The values of the control group are greater than 0.05. The teaching strategy of moral cultivation in EFL critical thinking ability has an obvious effect on improving students’ critical thinking abilities. There is a correlation between the development of critical thinking ability and teachers’ education, and teachers with master’s degrees are better than teachers with bachelor’s degrees.
Summary
Pre‐mRNA splicing is an important step for gene expression regulation. Yeast Bud13p (bud‐site selection protein 13) regulates the budding pattern and pre‐mRNA splicing in yeast cells; ...however, no Bud13p homologs have been identified in plants. Here, we isolated two mutants that carry T‐DNA insertions at the At1g31870 locus and shows early embryo lethality and seed abortion. At1g31870 encodes an Arabidopsis homolog of yeast Bud13p, AtBUD13. Although AtBUD13 homologs are widely distributed in eukaryotic organisms, phylogenetic analysis revealed that their protein domain organization is more complex in multicellular species. AtBUD13 is expressed throughout plant development including embryogenesis and AtBUD13 proteins is localized in the nucleus in Arabidopsis. RNA‐seq analysis revealed that AtBUD13 mutation predominantly results in the intron retention, especially for shorter introns (≤100 bases). Within this group of genes, we identified 52 genes involved in embryogenesis, out of which 22 are involved in nucleic acid metabolism. Our results demonstrate that AtBUD13 plays critical roles in early embryo development by effecting pre‐mRNA splicing.
Significance Statement
This study shows that AtBUD13, an Arabidopsis homolog of the yeast Bud13p splicing factor, is required for the efficient pre‐mRNA splicing of a subset of genes involved in early embryonic development and is essential for seed formation. Our results provide insights into the functions of AtBUD13 in early embryo development by effecting post‐transcriptional regulation of gene expression in Arabidopsis.
Photothermal therapy in the second near-infrared window (NIR-II, 1000-1700 nm) exhibits a significant advantage over the first near-infrared window (NIR-I, 650-950 nm) in terms of both maximum ...permissible exposure (MPE) and penetration depth. However, the thus far reported NIR-II photothermal agents (PTAs) have been focused just on inorganic semiconducting and organic polymeric semiconducting nanoparticles. Herein a novel cruciform phthalocyanine pentad was designed, synthesized, and characterized for the first time. The water-soluble nanoparticles (Zn
4
-H
2
Pc/DP NPs) assembled from this single molecular material with the help of DSPE-PEG
2000
-OCH
3
exhibit characteristic absorption in the NIR-II region at 1064 nm with a large extinction coefficient of 52 L g
−1
cm
−1
, high photothermal conversion efficiency of 58.3%, and intense photoacoustic signal. Moreover, both
in vitro
and
in vivo
studies reveal the good biocompatibility and notable tumor ablation ability of Zn
4
-H
2
Pc/DP NPs under 1064 nm laser irradiation. Theoretical density functional theory calculations interpret the two-dimensional compressional wave energy-dissipation pathway over the broad saddle curved framework of the cruciform conjugated phthalocyanine pentad, rationalizing the efficient photothermal properties of corresponding Zn
4
-H
2
Pc/DP NPs in the NIR-II window.
The first molecular material-based PTA for the NIR-II photothermal therapy with high PCE of 58.3% was reported. The Zn
4
-H
2
Pc/DP NPs reveal good biocompatibility and notable tumor ablation ability in 1064 nm.
Stimulus-responsive biodegradable nanocarriers with tumor-selective targeted drug delivery are critical for cancer therapy. Herein, we report for the first time a redox-responsive disulfide-linked ...porphyrin covalent organic framework (COF) that can be nanocrystallized by glutathione (GSH)-triggered biodegradation. After loading 5-fluorouracil (5-Fu), the generated nanoscale COF-based multifunctional nanoagent can be further effectively dissociated by endogenous GSH in tumor cells, releasing 5-Fu efficiently to achieve selective chemotherapy on tumor cells. Together with the GSH depletion-enhanced photodynamic therapy (PDT), an ideal synergistic tumor therapy for MCF-7 breast cancer
via
ferroptosis is achieved. In this research, the therapeutic efficacy was significantly improved in terms of enhanced combined anti-tumor efficiency and reduced side effects by responding to significant abnormalities such as high concentrations of GSH in the tumor microenvironment (TME).
Stimulus-responsive biodegradable nanocarriers with tumor-selective targeted drug delivery are critical for cancer therapy.
Most sharing mobility business models promise green and affordable transport in cities. However, their rapid scale-up processes have often caused significant disruption and stresses to urban ...governance. Free-floating bike sharing (FFBS) is highly-touted in Shanghai as a means to bring biking habits back to an overly car-congested city. Despite substantially changing the behaviour of Shanghai citizens to adopt shared bikes within a short period of time (2016–2017), the FFBS has hit a threshold of oversupply, under-distribution and user misbehaviour problems, which endanger the environmental and social sustainability of innovative urban mobility schemes. In this paper, we focus on the FFBS case study and examine how commercial, political and social actors interact in addressing the emerging public problems in the FFBS scale-up process from a collaborative governance perspective. We find that the lack of recognition and integration of new social actors, such as user groups, as agents in the scheme are key obstacles to a fully-functioning government-business-society collaborative regime. We argue that this hindrance is a function of the existing socio-economic relations within the city. Our results suggest that the city's government needs to be more agile to accommodate, nurture and integrate emerging social actors as governance partners in the sharing economy, in order to ensure its efficacy, resilience and sustainability. We propose an alternative governance model to improve the effectiveness of the collaborative governance regime towards urban sustainability through engaging the society in better and smarter ways in the sharing economy.
•This paper reveals the determinants driving DBS users’ sustainable usage behavior.•In total, 67.92% of the survey respondents had used DBS in sustainable ways.•Perceived behavioral control and moral ...obligation are the most important drivers.•The role of awareness of consequences in sustainable usage intention is nonsignificant.•Useful implications for promoting DBS users’ sustainable usage behavior are provided.
Bike sharing, especially dockless bike sharing (DBS), plays a key role in enhancing sustainable mobility in Chinese cities. Unsustainable usage modes and user behavior are increasingly serious problems confronting DBS in China that may substantially threaten its profits and supply. While existing studies have mainly focused on how to promote DBS, the issue of the sustainable usage of shared bikes has been largely overlooked. This paper examined the determinants affecting users’ sustainable usage intention and behavior by incorporating awareness of consequences and moral obligation into the theory of planned behavior. Based on partial least squares structural equation modeling, the questionnaire data of 705 users (67.92% of all respondents) who had used DBS in sustainable ways were empirically analyzed. The results revealed that perceived behavioral control and moral obligation are the most important factors driving users’ sustainable usage intention and behavior and that behavioral attitude and subjective norms also present significant positive effects on sustainable usage intention. In contrast to the hypothesized relationship, the awareness of consequences does not play a significant role in sustainable usage intention. Moreover, the empirical results ascertained that the extended model has stronger interpretation ability than the original model in predicting DBS users’ sustainable usage behavior. Eventually, some targeted managerial implications are proposed. This study enhances the current understanding of the sustainable usage behavior of DBS users and provides timely insights for policymakers and operators promoting sustainable bike-sharing practices in China and other countries operating DBS programs.
Congenital heart disease (CHD), the most common heart defect in children, refers to congenital disease with abnormal development of the heart or large blood vessels during the fetal period. The ...researchers suggest that children with CHD show more obvious neurodevelopmental disorders than children with normal development, and children with CHD may have a higher risk of social interaction and communication disorders. This is similar to the characteristics of children with autism spectrum disorder (ASD). However, the association between type of CHD and ASD is not well understood. This systematic review and meta-analysis will reveal the relationship between type of CHD and ASD.
We will search the Cochrane Library, Embase, PubMed, China National Knowledge Infrastructure, Wanfang, Chinese Scientific Journals Full text, and China Biology Medicine disc databases using relevant subject terms and free words. We will use a fixed effects model or random effects model for meta-analysis. The risk of bias will be assessed by the Newcastle-Ottawa Scale and the agency for health care research and quality. Heterogeneity will be tested by Q statistics and I² values. Publication bias will be detected by funnel plots and Egger test. Subgroup analyses and sensitivity analyses will also be used to explore and interpret the heterogeneity.
The study will afford additional insight into the investigation the association between type of CHD and ASD.
The results will provide evidence for the early identification and early intervention of ASD in children with CHD, which may contribute to improving the neurodevelopmental outcome of children with CHD.
Herein, we report the first reactive oxygen species (ROS)-responsive dithioketal-linked covalent organic framework (COF) for synergetic chemotherapy and photodynamic therapy (PDT) of cancer. The ...singlet oxygen (
1
O
2
)-responsive COF dissociation and DC_AC50 drug release complement and reinforce each other to allow an efficient combination of PDT and chemotherapy.
Herein, we report the first reactive oxygen species (ROS)-responsive dithioketal-linked covalent organic framework (COF) for synergetic chemotherapy and photodynamic therapy (PDT) of cancer.
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